Monthly Archives: November 2012

New Proposed Height Increase Method Using Gene Therapy On Engineered Pluripotent Mesenchymal Cells (Breakthrough!)

Me: I found these three studies which gave me another idea on how to possibly lengthen the long bones. The issue with this proposed method is that even in theory, there is only a small chance that it can increase the long bone’s length and only by a little, if the gene therapy is the only thing used. If we can combine the gene therapy method involved with a form of mechanical loading or invasive surgical distraction, the chances of achieving long bone lengthening will be increased dramatically.

Description & Analysis: What we see here is that genetically engineered pluripotent human mesenchymal stem cells can be grown and implanted with certain types of vectors which mutates them completely and causes them to overexpress on certain types of genes. In the first study, the already rhBMP-2 cells are injected even further with a new type of compound I am not familiar with, a lacZ gene, that encodes for beta-galactosidase. The researchers conclude very clearly that “the ability of GEPMC to engraft, differentiate, and stimulate bone growth“. If the GEPMCs can be mutated in vitro to have certain types of characteristics, why can we not just use gene therapy to cause the cells to overexpress chondrogenetic growth factors? In the 2nd study, we see that the vector used was to encapsulate BMP-2. After that the researchers injected doxycycline to control the growth of  bone. This means that after we get the first injection of MSCs in, that does not mean that we can do nothing to control the chondrogenesis anymore. Using doxycycline, we can cause the cells to probably be even more effective in the gene expression. The 3rd study state conclusively that “they can be genetically engineered to express desired therapeutic proteins inducing specific differentiation pathways.

Actual Method: The method is still invasive because it has to penetrate tissue and bone. Let’s assume the idea of LSJL is valid. That means that as long as we can get cell differentiation towards chondrogenesis, proliferation, and hypertrophy, then the bones can lengthen. I then proposed that we first use gene therapy to mutate at least 2 batches of a certain type of MSCs. We first extract the MSCs of the patient from their long bone to get the re-implant to be immunologically compatible. We then add one type of vector for each of the two groups. For the first batch of mutated MSCs, we use vectors to get to cause them to focus on only expressing chondrogenesis genes. Once we accomplish that, we inject this first group of cells into the epiphysis ends of the long bones through drilling. After the cells are added, we can wait for 1-4 weeks. After we are sure the differentiation is complete, we want to expand the number of chondrocytes inside. That is when we get the 2nd group of MSCS to focus on overexpressing the genes that produce the growth factors that lead to chondrocyte proliferation. This in theory should not only cause the already chondrocytes implanted to multiply, it should also get the original MCSs in the epiphysis to differentiate as wel and join with the implanted groupl. Sure, we could make the argument that only the 2nd group of implants are needed, but from what I have learned about crystal growing ,it is always  better idea to start with a seed, and have it grow bigger and bigger but getting the surrounding medium and raw material to transform into it and then layer on top of it. Once this is done, there will be a substantial amount of chondrocytes in the human epiphysis. Since LSJL theory says induced chondrogenesis proliferation will lead to bone lengthening, then this proposed method should lengthen the bone. We then can use compounds like doxycyline, to control the rate of bone growth. To help the bone growth further along by causing chondrocyte aggregation, we can then apply ESW therapy in that area to help the Chondrocytes already there to lead to hypertrophy and expand.


From PubMed study 1 link HERE

J Gene Med. 1999 Mar-Apr;1(2):121-33.

Engineered pluripotent mesenchymal cells integrate and differentiate in regenerating bone: a novel cell-mediated gene therapy.

Gazit D, Turgeman G, Kelley P, Wang E, Jalenak M, Zilberman Y, Moutsatsos I.
Source

Molecular Pathology Laboratory, Hebrew University-Hadassah Faculty of Dental Medicine, Jerusalem, Israel. dgaz@cc.huji.ac.il

Abstract

BACKGROUND:

Among the approximately 6.5 million fractures suffered in the United States every year, about 15% are difficult to heal. As yet, for most of these difficult cases there is no effective therapy. We have developed a mouse radial segmental defect as a model experimental system for testing the capacity of Genetically Engineered Pluripotent Mesenchymal Cells (GEPMC, C3H10T1/2 clone expressing rhBMP-2), for gene delivery, engraftment, and induction of bone growth in regenerating bone.

METHODS:

Transfected GEPMC expressing rhBMP-2 were further infected with a vector carrying the lacZ gene, that encodes for beta-galactosidase (beta-gal). In vitro levels of rhBMP-2 expression and function were confirmed by immunohistochemistry, and bioassay. Differentiation was assayed using alkaline phosphatase staining. GEPMC were transplanted in vivo into a radial segmental defect. The main control groups included lacZ clones of WT-C3H10T1/2-LacZ, and CHO-rhBMP-2 cells. New bone formation was measured quantitatively via fluorescent labeling, X-ray analysis and histomorphometry. Engrafted mesenchymal cells were localized in vivo by beta-gal expression, and double immunofluorescence.

RESULTS:

In vitro, GEPMC expressed rhBMP-2, beta-gal and spontaneously differentiated into osteogenic cells expressing alkaline phosphatase. Detection of transplanted cells revealed engrafted cells that had differentiated into osteoblasts and co-expressed beta-gal and rhBMP-2. Analysis of new bone formation revealed that at four to eight week post-transplantation, GEPMS significantly enhanced segmental defect repair.

CONCLUSIONS:

Our study shows that cell-mediated gene transfer can be utilized for growth factor delivery to signaling receptors of transplanted cells (autocrine effect) and host mesenchymal cells (paracrine effect) suggesting the ability of GEPMC to engraft, differentiate, and stimulate bone growth. We suggest that our approach should lead to the designing of mesenchymal stem cell based gene therapy strategies for bone lesions as well as other tissues.

PMID: 10738576     [PubMed – indexed for MEDLINE]

From PubMed study 2 link HERE

Mol Ther. 2001 Apr;3(4):449-61.
Exogenously regulated stem cell-mediated gene therapy for bone regeneration.
Moutsatsos IK, Turgeman G, Zhou S, Kurkalli BG, Pelled G, Tzur L, Kelley P, Stumm N, Mi S, Müller R, Zilberman Y, Gazit D.
Source

Molecular Pathology Laboratory, Hebrew University-Hadassah Medical and Gene Therapy Center, Jerusalem, Israel.

Abstract

Regulated expression of transgene production and function is of great importance for gene therapy. Such regulation can potentially be used to monitor and control complex biological processes. We report here a regulated stem cell-based system for controlling bone regeneration, utilizing genetically engineered mesenchymal stem cells (MSCs) harboring a tetracycline-regulated expression vector encoding the osteogenic growth factor human BMP-2. We show that doxycycline (a tetracycline analogue) is able to control hBMP-2 expression and thus control MSC osteogenic differentiation both in vitro and in vivo. Following in vivo transplantation of genetically engineered MSCs, doxycycline administration controlled both bone formation and bone regeneration. Moreover, our findings showed increased angiogenesis accompanied by bone formation whenever genetically engineered MSCs were induced to express hBMP-2 in vivo. Thus, our results demonstrate that regulated gene expression in mesenchymal stem cells can be used as a means to control bone healing.

PMID: 11319905     [PubMed – indexed for MEDLINE]     Free full text

From PubMed study 3 link HERE

J Gene Med. 2001 May-Jun;3(3):240-51.
Engineered human mesenchymal stem cells: a novel platform for skeletal cell mediated gene therapy.
Turgeman G, Pittman DD, Müller R, Kurkalli BG, Zhou S, Pelled G, Peyser A, Zilberman Y, Moutsatsos IK, Gazit D.
Source

Hebrew University-Hadassah Medical and Gene Therapy Center, Jerusalem, Israel.

Abstract

BACKGROUND:

Human mesenchymal stem cells (hMSCs) are pluripotent cells that can differentiate to various mesenchymal cell types. Recently, a method to isolate hMSCs from bone marrow and expand them in culture was described. Here we report on the use of hMSCs as a platform for gene therapy aimed at bone lesions.

METHODS:

Bone marrow derived hMSCs were expanded in culture and infected with recombinant adenoviral vector encoding the osteogenic factor, human BMP-2. The osteogenic potential of genetically engineered hMSCs was assessed in vitro and in vivo.

RESULTS:

Genetically engineered hMSCs displayed enhanced proliferation and osteogenic differentiation in culture. In vivo, transplanted genetically engineered hMSCs were able to engraft and form bone and cartilage in ectopic sites, and regenerate bone defects (non-union fractures) in mice radius bone. Importantly, the same results were obtained with hMSCs isolated from a patient suffering from osteoporosis.

CONCLUSIONS:

hMSCs represent a novel platform for skeletal gene therapy and the present results suggest that they can be genetically engineered to express desired therapeutic proteins inducing specific differentiation pathways. Moreover, hMSCs obtained from osteoporotic patients can restore their osteogenic activity following human BMP-2 gene transduction, an important finding in the future planning of gene therapy treatment for osteoporosis.

PMID:  11437329     [PubMed – indexed for MEDLINE]

Using Short Term Mechanical Stimulation To Differentiate Human Bone Marrow-Derived Stem Cells Through Osteogenesis

This post is to focus on the cellular and orthopedic mechanics. One of the best things about this post is to see which articles and studies it has been using as a reference and some of the studies it does cite are extremely insightful on what may be the next approach to get the bone’s to respond correctly.

Analysis & Interpretation

It seems the researchers already know that long term stimulation through some type of mechanical or biological means of the bone marrow derived stem cells (BMSCs) causes them to differentiate into bone cells. Now they want to see from this study where just a small short stimuli would also work in stimulating BMSC differentiation into osteocytes.

I have posted the entire study below but I would only be going over the abstract and conclusion since those parts are the most critical. The amount of loading that was done was 24 hours of cyclic loading at a frequnecy of 0.05 HZ and force/area load of 4 kilapascals. The BMSCs where placed in a type of scaffold/solid porous medium and then solid was hit by the mechanical dynamic load. The BMSCs started to turn on/express the right type of genes that cause them to differentiate/change into bone cells.

There are the growth factors that increased

  • Osteopontin
  • Integrin – Beta1
  • Transforming growth factor – Beta receptor 1
  • SMAD
  • Platelet derived Growth Factor -alpha
  • annexin -V

The researchers conclude that the main reason these growth factors increased is from the cyclical loading on the bone. As stated, “it may be postulated that short-term mechanical stimulation results in an improved osseous integration of tissue engineered grafts in bone defect healing

Implications For Height Increase

It has shown quite conclusively that for bone formation, the cyclical dynamic loading that is done to the stem cell holding fibrillin matrix material causes the progenitor cells to be more osteogenic in nature. The real question now is to see whether the same type of compressive loading will cause the same for cartilage formation. and if it does lead to chondrogenesis, in what ratio to bone formation. We have found now so many ways that are non-invasive to stimulate bone growth but the bone growth is for denstiy, but not volume increases longitudinally.

From PubMed study link Osteogenic Predifferentiation of Human Bone Marrow-Derived Stem Cells by Short-Term Mechanical Stimulation


Open Orthop J. 2011; 5: 1–6.        Published online 2011 January 7. doi:  10.2174/1874325001105010001        PMCID: PMC3027083
Doerte Matziolis, Jens Tuischer, Georg Matziolis, Grit Kasper, Georg Duda, and Carsten Perka
Abstract

It is commonly accepted that bone marrow-derived stem cells (BMSCs) have to be expanded in vitro, but a prolonged time in culture decreases their multilineage potential. Mechanical and biological stimuli have been used to improve their osteogenic potential. While long-term stimulation has been shown to improve osteogenic differentiation, it remains to be seen whether short-term stimulation is also sufficient.

We investigated the influence of 24 hours’ cyclic loading (0.05Hz, 4kPa) on gene expression of human BMSCs in three-dimensional fibrin-DMEM constructs (n=7) in a compression bioreactor using DNA-array technology. Expression of the following genes showed a significant increase after mechanical stimulation: 2.6-fold osteopontin (OPN) and integrin-β1 (ITGB1), 2.2-fold transforming growth factor-β-receptor 1 (TGF-β-R1) and 2.4-fold SMAD5 expression, compared to controls without mechanical stimulation (p<0.05 each). Platelet-derived growth factor-α (PDGF-α ) and annexin-V were also significantly overexpressed, the mechanical stimulation resulting in a 1.8-fold and 1.6-fold expression (p<0.05).

Cells were identified as osteoblast precursors with a high proliferative capacity. Given the identical in-vitro environment for both groups, the increase in gene expression has been interpreted as a direct influence of cyclic mechanical stimulation on osteogenic differentiation. It may be postulated that short-term mechanical stimulation results in an improved osseous integration of tissue engineered grafts in bone defect healing.

Keywords: Osteogenic predifferentiation, human bone marrow-derived stem cells, mechanical stimulation, bioreactor.
INTRODUCTION

Major bone defects remain an unsolved therapeutic problem in orthopaedic surgery, especially in revision arthroplasty, treatment of pseudarthrosis or after tumour resections [1]. The use of autologous and allogenic bone grafts is the most widely used regenerative approach [2]. Fundamental differences in biology have been noted in these two approaches: Allografts demonstrate only osteoconductive capacity with low overall integration and an unsatisfactory long-term clinical outcome [3-5]. Autografts show osteoinductive and osteogenic characteristics, leading to significantly better clinical results [6]. However, their use is limited by restricted availability and significant donor-site morbidity [7].

A therapeutic approach that harnesses the osteogenic potential of autografts, without the limitations of low availability and high donor-site morbidity is still missing in the treatment of bone defects.

Therefore, autologous osteogenic cells like periosteum-derived cells in different matrices have been investigated in regenerative bone defect therapy and promising results have been published [8, 9]. Bone marrow-derived stromal cells have also been investigated in animal and clinical trials, an accelerated healing of bone defects being reported [10-13].

BMSCs have little donor-site morbidity and are easily expanded in vitro [14], but their multilineage potential and proliferative capacity decreases with time in vitro [15]. It has therefore been recommended to keep the in-vitro phase as short as possible in clinical situations [16, 17]. A predifferentiation of cells during the in-vitro period has been reported to be beneficial, as the osteogenic potential of BMSCs can be augmented through biological or mechanical stimulation lasting for several weeks [18, 19].

In the present study we wanted to investigate whether a short-term mechanical stimulation of just 24 hours is sufficient to achieve an osteogenic predifferentiation in vitro. A short period of stimulation and thereby short in-vitro time might be advantageous for subsequent in-vivo use. Maintaining the high proliferative capacity and directing the cellular differentiation into an osteogenic lineage may improve results of cell-based approaches in the treatment of bone defects.

MATERIALS AND METHODOLOGY

Study Design

BMSCs were harvested from seven different donors, all cells then being expanded separately in cell-culture flasks. After a sufficient amount of cells had been achieved, they were transferred into three-dimensional constructs consisting of an elastic fibrin-DMEM matrix and then put between two slices of freeze-dried cancellous bone. All constructs were placed in bioreactors, as described previously [20]. Half of the constructs underwent cyclic mechanical compression; the other half remained without mechanical stimulation as a control. The gene expression in mechanically stimulated cells was normalized versus unstimulated controls.

Cells and Cell Culture

The BMSCs were gained from aspirates of the proximal femur during total hip arthroplasty operations. All 7 donors (4 female, 3 male, average age 61 years) gave informed consent. A pre-existing bone disease was excluded anamnestically and by bone densitometry investigation (Lunar-DPX, USA). Approximately 5ml bone-marrow aspirate were harvested from the intertrochanteric region of the proximal femur, and kept at 8°C until further processing within 4 hours.

Density centrifugation was performed (Histopaque 1.077g – Sigma-Aldrich, Germany) for 15 minutes at 1500rpm. The interphase containing the BMSCs was transferred into culture medium (DMEM + 10% FCS [Biochrome, Germany] + 100U/ml penicillin + 100µg/ml streptomycin [Sigma-Aldrich, Germany]). The cells were dispersed in culture flasks (Falcon, Greiner, Germany) and then incubated at 37°C and 5% CO2. Passage into a new flask was performed at approximately 70% confluence.

3D Matrix/Bone-Fibrin-DMEM Constructs

After having reached passage 3 in the above given cell culture medium, cells were transferred into 3D constructs, consisting of a fibrin-DMEM-mix matrix and placed between two slices of freeze-dried human cancellous bone. Every construct contained 1×106 cells in 600µl DMEM + 10%FCS (Biochrome, Germany) + 100U/ml penicillin + 100µg/ml streptomycin (Sigma-Aldrich, Germany) + 2.4% aprotinin (Bayer, Germany). For polymerization 30µl fibrinogen and 1IU/ml thrombin (Aventis, Germany) were added. The matrices hardened for one hour at 37°C at 5% CO2, before being transferred into the bioreactors.

The freeze-dried cancellous bone slices measured 15mm in diameter and 4mm in depth. Prior to construct mounting, they were rehydrated for two hours in culture medium.

Mechanical Stimulation in the Compression Bioreactor

The principle of the compression bioreactor (Fig. 11) has been described previously [20]. A closed cylindrical polyethylene chamber communicates with the incubator via four sterile filters (0.2µm pore diameter). The cell-matrix constructs were mechanically stimulated between two flexible silicon membranes. While the upper membrane loads the construct (Fig. 22) perpendicularly to its surface, the lower membrane transfers the pressure via a standard infusion tube to a pressure transducer.

Fig. (1)

Fig. (1)
Compression bioreactor for cyclic loading of the constructs under sterile culture conditions.

Fig. (2)

Fig. (2)
Construct with BMDSCs in a fibrin matrix.

In the present experiment, we applied a cyclical pressure of 4kPa, resulting in a deformation of approximately 1mm (Δh/h=25%), at a frequency of 0.05Hz. The loading environment of the lower extremities during physiological activities such as walking and running is cyclic [21], and the frequency used in our experiment has been described to be within physiological conditions [22]. Control constructs (n=7) were cultivated in bioreactors without mechanical stimulation. After 24 hours, the cyclic compression was terminated and the constructs were harvested.

RNA Extraction and Gene Expression

RNA isolation was started within two minutes. Under sterile conditions the fibrin-DMEM matrices were harvested from the compression bioreactors: the matrix was dissected sharply from the cancellous bone and transferred immediately into 2ml RNA-extraction solution (Trifast, Peqlab, Germany). Matrices were homogenized mechanically (Ultra-Turrax-T8, IKA, Germany) directly afterwards. The RNA extraction was performed according to the protocol of the supplier. RNA integrity was controlled in a Bio Sizing Assay (Eukaryote Total RNA Nano, Agilent Technologies 2100 Bioanalyzer, Germany). After measurement of total RNA using a photometer, the RNA was stored at -140°C until further use.

The expression of osteogenesis-specific genes was investigated using the GEArray-Q-Series Human Osteogenesis Gene Array (Biomol, Germany). 3-3.5µg total RNA was used for each array. cDNA synthesis was accomplished at 37°C for 25 minutes. The subsequent labelling was carried out with Biotin-16-dUTP (Roche, Germany) and an amplification labelling kit (Biomol, Germany) according to the protocol of the supplier. 30 cycles of PCR amplification were implemented, with 85°C, 50°C and 72°C for 1 minute each (MJ Research Inc, USA). Hybridisation of the PCR product on the arrays was carried out at 56°C for 12 hours. Unspecific binding had been blocked by prehybridisation with salmon-sperm DNA (Roche Diagnostics, Germany) for 2 hours. After labelling with streptavidin-biotin antibodies and addition of CDP-Star solution (Biomol, Germany), the array signal was transmitted onto x-ray films (Kodak, Germany). Films were developed and scanned. The gene expression was analyzed using the programs ScanAlyze Version 2.5 (Eisen Software, USA) and GEArray Analyzer 1.3 (Superarray, USA). Following the recommendation of the array supplier, genes with unreliably low signals were excluded from further analysis.

STATISTICS

Statistical analysis was performed using SPSS 12.0. After background subtraction, the signals were normalized to the GAPDH as house keeping gene. The evaluation was carried out comparing directly the expression of mechanical stimulated cells versus controls of one donor. The expressions of the controls were defined as 1. All experiments were done in triplicate for all the 7 patients, all samples were subjected to DNA array analysis. A Wilcoxon signed rank test was carried out for statistical testing, a level of significance of p=0.05 was chosen.

RESULTS

The RNA isolation was successful in all cases; all specimens could be included in the data analysis (Table 11). We noted a strong expression of core-binding-factor-1 (Cbfa1) in all BMSCs, showing no significant difference between the two treatment groups (p=0,463). We found significant differen-ces in the expression of mechanically stimulated BMSCs compared to controls, as shown in Fig. (33).

Table 1.

Table 1.
Mean Changes in mRNA Expression of BMDSCs Through 24h of Mechanical Stimulation Normalized Versus Control Group w/o Mechanical Stimulation Measured with a Human Osteogenesis Gene Array (Biomol, Germany)

Fig. (3)

Fig. (3)
Gene expression of mechanically loaded constructs normalized vscontrol constructs without mechanical stimulation.
Matrix Proteins

A significant difference was noted for the expression of the osteopontin (OPN) gene, which showed a 2.6-fold expression in mechanically stimulated cells, compared to controls (p=0.043).

Cell-Surface Receptors

Furthermore, we found a 2.6-fold increase in the expression of the integrin-β-1 gene and a 2.2-fold increase in the expression of the transforming-growth-factor-beta-receptor 1 (TGF-β-R1), both differences being significant (p=0.018).

Intracellular Signalling Molecule

The mechanical stimulation also had a direct effect on the expression of an intracellular signal molecule, the SMAD-5 gene, which showed a 2.4-fold increase (p=0.028).

Moreover, we found significant increases of two other genes: 1.8-fold for platelet-derived growth factor-alpha (PDGF-(α ) (p=0.027) and 1.6-fold for annexin-V (p= 0.034).

DISCUSSION

BMSCs show high proliferative capacity and do not undergo terminal osteoblast differentiation in vitrowithout external stimulation. In the present study, we could show for the first time that 24 hours of cyclic compression is able to increase the expression of several osteogenesis-specific genes and thereby lead to an osteogenic predifferentiation of BMSCs.

The gene expression analysis showed a marked expression of Cbfa1, the master control gene of osteoblastic differentiation [23]. The BMSCs shifted to the level of immature osteoprogenitors [24].

By definition, these cells do not yet show expression of the typical markers for osteogenesis, like osteocalcin, alkaline phosphatase or type-I collagen, which were not detectable in our trial. However, they do express the non-collagenous matrix protein osteopontin [25], which was significantly increased by mechanical stimulation in our setting. It might be hypothesized that more BMSCs were directed towards immature osteoprogenitors.

As a non-collagenous protein of the bone matrix, OPN has further influences on bone metabolism: amongst others, it plays an important role during bone remodelling, inflammation and under mechanical stress [25, 26]. An elevated OPN expression has also been noted during the early phase of fracture healing, prior to callus formation. As Kawahata and co-worker hypothesized that it might be a trigger for osteogenesis [27], the increased expression of OPN after 24 hours of cyclic compression may be an indicator of initial osteogenesis.

Another important effect of OPN has been identified in mice: ectopically implanted autologous bone showed lower transplant vascularization and integration, due to reduced bone remodelling [28]. A 2.6-fold increase of OPN expression by mechanical stimulation of constructs with BMSCs might thus augment bone remodelling and improve transplant vascularization and integration.

The mechanically stimulated BMSCs also showed an increased expression of integrin-β 1, a part of transmembrane glycoprotein that forms heterodimers with integrin-α subunits and links the cytoskeleton to the extracellular matrix. The importance of integrin-β1 in osteogenesis and osteoblast function has been shown in mice [29]. Together with the α1-3 subunits, it binds to collagen, and ligand-binding leads to increased expression of osteoblast markers [30, 31]. The β1-subunit has been identified as the most important integrin in the development of BMSCs to osetoblasts [32]. Its increased expression might signalize the promotion of osteogenic differentiation in BMSCs following 24 hours of mechanical stimulation.

In addition, the mechanically stimulated BMSCs showed a significant increase in the expression of the TGF-ß-receptor1 [33]. This receptor has been identified on osteoprogenitor cells and also on terminally differentiated osteoblasts [34]. Its ligand TGF-ß has been shown to be involved in the regulation of proliferation and migration of progenitor cells and leads to an increase of osteoblastic differentiation, independently of their differentiation state [35]. It promotes osteogenic differentiation in BMSCs, with enhanced matrix synthesis and calcification [36, 37]. The mechanically stimulated BMSCs with an increased expression of the TGF-β-receptor1 might therefore be more sensitive to TGF-ß stimuli and show augmented osteogenic differentiation when implanted into bone defects.

The increase of the intracellular signal molecule Smad-5 may be another indicator of osteogenic predifferentiation. Smad-5 interacts with Smad-1 and mediates signals from cytokines of the TGF-ß superfamily, and among them the osteoblastic differentiation of progenitor cells [38, 39]. This may result in a facilitation of osteogenic differentiation of mechanically stimulated cells in bone defects.

The expression of the growth factor PDGF-α also increased following mechanical stimulation. PDGF-α is known to induce osteogenic differentiation, has additional chemotactic effects on osteoprogenitor cells and enhances the proliferation of osteoblasts [40]. These are all effects that may contribute to improved results following mechanical stimulation of BMSCs before using them in cell-based therapies.

Annexin-V gene expression was significantly increased after mechanical stimulation. Annexin-V protein builds Ca2+ channels, leading to mineralization of bone matrix in the growth plates during osteogenesis [41]. An increased expression of annexin-V enhances these processes of mineralization [42]. Such mineralization processes were observed in a prior study, whereas periosteal cells underwent long-term mechanical stimulation in bioreactors [20].

CONCLUSION

In recent years, different methods have been developed to stimulate osteogenic differentiation of BMSCs in vitro an in vivo, like medium supplements, growth factors or viral transfection [1, 43]. The approach of mechanical stimulation presented here is advantageous, because it can be directly transferred to clinical application. The selected fibrin matrix allows temporary fixation of BMSCs in a bone defect and has shown excellent biocompatibility [8, 44].

Our results show a concomitant increase of genes coding for matrix molecules, receptors and growth factors by mechanical stimulation. The presented data indicate that 24 hours are sufficient to obtain changes in gene expression, resulting in an osteogenic predifferentiation of BMSCs. The shift towards immature osteoprogenitor cells combines the desired high proliferative capacity with an osteogenic potential that makes them a promising tool in cell-based treatment of bone defects. It may be postulated that short-term mechanical stimulation will result in an improved osseous integration of tissue engineered grafts in bone defect healing.

Effects of Physical Activity on the Epiphyseal Growth Plates

[Note: This post is a resource post which only has information to help me build a atronger understanding on the effects of physical activity and loading on the epiphyseal growth plates.]

If you really wish to join me and the other height increase researchers, this page would be a very post to read and fully understand. The main thing to take away is that too much loading can disrupt the endochondral ossification process and cause fracture in the cartilage for young kids. Too little physical activity seems to decrease the bone density and cause the ability of the estrogen released during the initial part of puberty to not cause as great of chondrocyte hypertrophy (thus height increase) than if the young child does get some degree of physical activity.

The information below was taken from the website for the Journal of Clinical Medicine Research, Vol. 3, No. 1, Feb 2011. The source link is from HERE

[Note: There was a References section below the post below which I decided not to copy and paste below]


Journal of Clinical Medicine Research, Vol. 3, No. 1, Feb 2011

Home > Vol. 3, No. 1, Feb 2011 > Mirtz   –    Volume 3, Number 1, February 2011, Page 1-7
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Journal of Clinical Medicine Research, ISSN 1918-3003 print, 1918-3011 onlineArticle copyright, the authors; Journal compilation copyright, J Clin Med Res and Elmer PressTMJournal website http://www.jocmr.org

The Effects of Physical Activity on the Epiphyseal Growth Plates: A Review of the Literature on Normal Physiology and Clinical Implications

Timothy A. Mirtza, c, Judy P. Chandlerb, Christina M. Eyersb

aDivision of Health Physical Education and Recreation, University of South Dakota, Vermillion, South Dakota, USA
bDepartment of Physical Education and Sport, Central Michigan University, Mt. Pleasant, Michigan, USA
cCorresponding author: 221B Dakota Dome, 414 East Clark Street, University of South Dakota, Vermillion, South Dakota 57069, USA. Email: timothy.mirtz@usd.edu

Manuscript accepted for publication November 23, 2010
Short title: Physical Activity on Epiphyseal Growth Plates
doi:10.4021/jocmr477w

Abstract

Background: Children need physical activity and generally do this through the aspect of play. Active play in the form of organized sports can appear to be a concern for parents. Clinicians should have a general physiological background on the effects of exercise on developing epiphyseal growth plates of bone. The purpose of this review is to present an overview of the effects of physical activity on the developing epiphyseal growth plates of children.

Methods: A National Library of Medicine (Pubmed) search was initiated using the keywords and combinations of keywords growth plate, epiphyseal plate, child, exercise, and physical activity.

Discussion: Bone is a dynamic tissue with a balance of osteoblast and osteoclast formation. The normal functioning of the epiphyseal growth plate is an important clinical aspect. Much of the physiology of the epiphyseal growth plate in response to exercise includes the important mechanical component. Growth hormone, insulin-like growth factor I, glucocorticoid, thyroid hormone, estrogen, androgen, vitamin D, and leptin are seen as key physiological factors. While there is a need for children to participate in physical activity, clinical consideration needs to be given to how the epiphyseal growth plate functions.

Conclusions: Mechanical loading of the bone is important for epiphyseal plate physiology. Exercise has a healthy function on the normal growth of this important biomechanical feature. Clinically, over-exertion in the form of increased load bearing on the epiphyseal growth plate creates an ideal injury. There is a paucity of research on inactivity on the epiphyseal growth plate resulting in stress deprivation. Further research should take into consideration what lack of exercise and lessened mechanical load bearing has on the function of the epiphyseal growth plate.

Keywords: Child; Physical activity; Epiphyseal growth plates; Bone; Exercise; Mechanical loading

Introduction

Bone has been described as a dynamic and highly interactive complex of many cell and tissue types [1]. The epiphyseal growth plate is made of several key aspects including cartilaginous,bony, and fibrous components, which act together to achieve longitudinal bone growth [2]. The epiphyseal growth plate is a final target organ for longitudinal growth and results from the cellular process of chondrocyte proliferation and differentiation [3]. Jaramillo and Hoffer [4] described the cartilaginous structures at the ends of growing bones as constituting the “growth mechanism. Frost [5] noted that knowledge of epiphyseal growth plate physiology has application for several areas. The first area noted being that such knowledge aids in distinguishing mechanically competent bone from incompetent bone [5]. The second area is that this knowledge enables a person to increase and maintain bone strength during growth [5]. Finally,knowledge that bone strength, taken in its entirety, and bone health are to be understood as completely different from each other with regards to physiological responses [5]. Of particular importance to clinical practice is the knowledge that two major contributions to the development of articular cartilage are growth factors and mechanical loading [6].

The purpose of this review is to present an overview of the effects of physical activity on the developing epiphyseal growth plates of children. A discussion of the physiological basis of epiphyseal growth plates will be included. Practitioners with a familiarity of the dynamic changes that can occur with the epiphyseal plate in normal children can ultimately lead to recognition of pathologic states [7, 8].

A Review of the Normal Physiology of the Epiphyseal Growth Plate

As noted previously, skeletal growth at the epiphyseal plate is an active and dynamic process [8]. The epiphyseal growth plate, being a highly specialized layer of cartilage where chondrocytes proliferate and differentiate, brings forth longitudinal bone growth [9]. The epiphyseal growth plate can be divided into three main chondrocyte subpopulations: the resting,proliferating and hypertrophic chondrocytes [10].

Longitudinal bone growth is primarily achieved through the action of chondrocytes in the proliferative and hypertrophic zones of the growth plate [11]. Longitudinal bone growth occurs in the epiphyseal growth plate through a process called endochondral bone formation and ossification [12-14]. Endochondral bone formation is a process where resting zone chondrocytes are recruited to start active proliferation and then undergo differentiation, followed by mineralization [12]. Production of metaphyseal cancellous bone and growth in length are both linked to endochondral ossification with growth plate cartilage cell proliferation as the driving force [15].

Within the epiphyseal growth plate, chondrocyte proliferation, hypertrophy, and cartilage matrix secretion result in chondrogenesis [14]. Endochondral bone development leading at the epiphyseal growth plate contributes to longitudinal bone growth through a process through which undifferentiated mesenchymal cells differentiate into chondrocytes, which then undergo well-ordered and controlled phases of proliferation, hypertrophic differentiation, death, blood vessel invasion, and finally replacement of cartilage with bone [16]. The newly formed cartilage is invaded by blood vessels and bone cells that remodel the newly formed cartilage into bone tissue [14].

The regulation of linear bone growth in children and adolescents comprises a complex interaction of hormones and growth factors [17]. This process of longitudinal bone growth is governed by an intricate network of endocrine signals, including growth hormone, insulin-like growth factor I, glucocorticoid, thyroid hormone, estrogen, androgen, vitamin D, and leptin [14]. Many of these signals act locally on growth plate chondrocytes to regulate epiphyseal growth plate function [14]. The regulation of longitudinal growth at the epiphyseal growth plate occurs generally through the intimate interaction of circulating systemic hormones and locally produced peptide growth factors which has the net result of triggering changes in gene expression bygrowth plate chondrocytes [13].

In particular, for the majority of skeletal elements to develop and grow, the process of endochondral ossification requires a constantly moving interface between cartilage, invading blood vessels, and bone [1]. An adequate supply of calcium is critical for normal epiphyseal growth plate development and that changes in extracellular calcium modulate the function of chondrocytes with high calcium [Ca2+] leading to cell differentiation [18]. The active metabolite of vitamin D, 1,25-dihydroxyvitamin D (1,25(OH)2D), is classically appreciated to exert its calcemic and other actions via interaction with the vitamin D receptor thus modulating gene transcription [19]. However, with respect to parathyroid gland function and development of the cartilaginous epiphyseal growth plate, calcium and 1,25(OH)2D act cooperatively and 1,25(OH)2D will act independently of the vitamin D receptor [19].

The balance between proliferation and differentiation in bone is considered to be a crucial step.  It is a crucial regulatory step controlled by various growth hormones acting in the endocrine pathways [12]. Growth hormone (GH) and insulin-like growth factor-I have major effects on the chondrocytes of the growth plate and act upon all bone cells [20]. Growth hormone (GH), mostly seen in action during the growth spurt in early adolescence, is considered to be the key hormone regulator of linear growth during childhood [17].

Research with laboratory animals has provided most of the current information regarding estrogens influence on the growth process of long bones, on the maintenance of cancellous bone mass, and on the architectural and cellular changes in bone [21]. Estrogen action is indispensable for normal pubertal growth and growth plate fusion. Both estrogen receptors (ER), ER-alpha and ER-beta, are expressed in the growth plate in boys and girls throughout pubertal development [12]. The rise in estrogen levels at menarche in girls is associated with a large reduction in bone turnover markers and reflects the closure of the epiphyseal growth plates, the reduction in periosteal apposition and endosteal resorption within cortical bone [22].Jarvinen [23] noted that estrogen tends to pack mechanically-excess mineral into the female skeleton at puberty thus creating the paradigm that the most responsive period of female bone to mechanical loading occurs prior to menarche. This knowledge has consequence for the encouragement of physical activity especially for the female population.

As previously noted, longitudinal growth of the skeleton is a result of endochondral ossification that occurs at the epiphyseal growth plate. Through the sequential process of cell proliferation, extracellular matrix synthesis, cellular hypertrophy, matrix mineralization, vascular invasion, and eventually apoptosis, cartilage continually is being replaced by bone as length increases [15]. Parfitt [15] explained that genetic determination of bone mass is mediated by two classes of gene. The first class of gene (under the control of the sizostat) regulates growth of muscles and bones [15]. The second class of gene (under the control of the mechanostat) regulates the increase in bone density in response to load bearing [15]. With skeletal maturity, there is a decreased growth rate and is mainly associated with structural changes in the physis, including a gradual decline in growth plate width due to the reduced height of the proliferative and hypertrophic zones [13].

Mechanical Influence on the Physiology of the Epiphyseal Growth Plate

Comprehension of the biomechanical aspects of bone allows one to conceptualize the physiological processes associated with exercise and physical activity on the epiphyseal growth plate.The mechanical influence on bone directly applies to the normal physiological functioning of bone. Longitudinal growth is controlled by local mechanical factors in the form of a feedback mechanism which exists to ensure that bone growth proceeds in the direction of the predominant mechanical forces [11]. The individual epiphyses undergoes a characteristic series ofevents; central calcification, absorption of cartilage and endochondral ossification, the further course of which is definitely determined by the degree of local distortion [24]. Production of diaphyseal cortical bone and growth in width are both linked to periosteal apposition driven by the process of osteoblast precursor proliferation [15]. During adolescence the trabeculae and cortices become thicker by endosteal apposition which increases bone density [15]. Intrinsically, biophysical forces placed upon the bone assist to develop the growing bone while extrinsic biophysical forces tend to resist and channel the expansion of bone into its functional forms such as the internal trabecular architecture and the external shape [25].

In addition to the vital function of growth factors, it is known that mechanical forces stimulate the synthesis of extracellular proteins in vitro and in vivo and can affect the tissue’s overallstructure [7]. According to the mechanostat theory, periosteal apposition is regulated by biomechanical requirements [11]. The stress acting on the cartilaginous epiphysis is comparable tothat in the adult with relative differences attributed to variations in the mechanical relationship and to the hormonal control of the body’s growth [24]. Frost [5] noted that later-discovered tissue-level mechanisms and functions (including biomechanical and muscle) are the true key players in bone physiology, and homeostasis ranks below the mechanical functions.

The Role of Exercise and Physical Activity on the Epiphyseal Growth Plate

Over the past decade, there has been a surge in the number of sports opportunities available to young athletes [26]. Beyond the positive physiological, psychological and social aspects that a sports activity brings to adolescents, there exists the potential risk of injuries and overuse of the locomotor system [27]. Nonetheless, pursuing sports as a leisure time activity has not been found to be harmful for children [28]. However, this must be coupled with proper instruction, appropriate amounts of physical activity as well as safety.

The effects of exercise on the molecular nature of secreted human growth hormone (GH) or its biological activity are not well understood [29]. Yet it is known that children have more elastic soft tissue and more potential for remodeling than adults [30]. Epiphyseal growth plates are often less resistant to deforming forces than ligaments or joint structures. A child’s skeletal system shows pronounced adaptive changes to intensive sports training [31, 32]. The growing skeleton is said to be more responsive than the mature skeleton to the osteotrophic effect of exercise [14]. The mechanstat, a process which is mediated by the detection of deviations from a target value for strain and is a conglomeration of cellular responses that tend torestore target values [15]. From this, the genetic influence on bone mass and density are largely mediated by body size, bone size, and muscle mass [15]. Most long bones end near the joint in a separate epiphysis which at first consists of cartilage and is later ossified [24]. This epiphysis becomes fused with the shaft of the bone and in most cases only at the end of puberty [24]. Thus the stage of growth and development of the child is suggestive of the amount and intensity of exercise that can be performed and tolerated. The recommendation that children, especially adolescents should not perform activities such as plyometrics or engage in heavy weight lifting and should concentrate mainly on such activities that encourages high repetitions at a very low weight [33].

Vascularization of the epiphyseal growth plate region represents a key mechanism for the coupling of two fundamental processes determining the rate of bone growth: chondrogenesis(cartilage production) and osteogenesis (bone formation) [34]. Within the epiphyseal cartilages of such anatomical entities such as the capitellum, trochlea, and medial and lateral epicondyles, vascularity is centripetal [35]. Due to the vascularity pattern it is difficult for avascular necrosis to develop after trauma within the epiphyses [35]. This type of vascularity would represent intraosseous vascularity whereas blood supply outside the epiphyseal plate would represent extraosseous vascularity. This is due in part that there is no true blood supply to the physis but rather the blood supply advances from the blood vessels of the epiphysis and metaphysis and from the perichondrial ring and vessels of the periosteum [36].

Influence of Over-activity on the Epiphyseal Growth Plate

A potential problem with physical activity and exercise on the epiphyseal plates is over-activity. Intuitively, it is the extent that over-physical activity may have on the growth plate resulting in injury. A better appreciation of how epiphyseal plate physiology works is seen in the response to trauma.  Approximately 25% of adolescents have at least one recreational injury which is mostly minor reflecting only soft tissue trauma and abrasions of the skin [37]. However, approximately 15% of children with fractures involve physeal injuries with 10% of these physeal injuries being sport-related [36]. The most prevalence of epiphyseal growth plate injuries is to children ages 10 to 16 years [38, 39]. If injury occurs to the epiphyseal growth plate the possibility that there may be a premature locking of the epiphyseal growth plate essentially halting bone lengthening [40].

Most injuries in childrens sports and activities are minor and self-limiting thus suggestive that children and youth sports are safe [32]. Unlike adults, many of the injuries may be treated closed due to the growth and remodeling potential of children [41]. Skeletally immature children who participate in extreme levels of sports participation can sustain repetitive trauma[42]. This repetitive trauma can cause the epiphyseal plate to widen. Laor et al [42] hypothesized that the  metaphyseal vascular supply is disrupted causing the normal process of endochondral bone formation due to long columns of hypertrophic cartilage cells from the physis extending into the metaphysis  As the risk of injuries sustained by young athletes can be significant, it is essential that training programs take into account physical and psychological immaturity, so that the growing athlete can adjust to their own body changes [31]. The period of early puberty is associated with an increased risk of fracture which may be related to the high rate of bone turnover [22]. A late menarche is a consistent risk factor for fracture in young females due to hormonal instability that may affect bone density [22]. Growth disturbance depends on extent of the injury and the amount of remaining growth potential [36].However, it can be hypothesized that a partially closed physis are weak links in children and that asymmetrically or partially closed physis may be vulnerable to trauma [43]. It has been suggested that overuse during puberty for females may result in long term development of low bone density and ongoing problems with bone health.

The genetic potential for bone accumulation can be frustrated by insufficient calcium intake, disruption of the calendar of puberty and inadequate physical activity [15]. While many of the molecular mechanisms that control cellular differentiation and growth during embryogenesis recur during fracture healing taking place in a post-natal environment that is unique and distinct from those which exist during embryogenesis [44]. Disruption of either the longitudinal intraosseous vasculature (vertical extraosseous blood supply) or the vascular arch in morethan two places may lead to selective avascular necrosis (extraosseous) of the epiphyseal cartilage [35].

The clinical pathophysiology of excessive activity on the epiphyseal growth plates resulting in injury is one of the more prominent methods of understanding the effects of exercise on growth plate physiology. The immature skeleton is different from the adult skeleton with unique vulnerability to acute and chronic injuries at the growth plate [7]. Epiphyseal injuries are usually due to shearing and avulsion forces as well as compressive forces usually due to either severe twisting or direct blows that can result in a disruption of the epiphyseal growth plate[31]. In young athletes, as the bone stiffness increases and resistance to impact diminishes, sudden overload may subject bone to either bow or buckle [31]. Swelling, hyperemia, and deformity in the physeal area are the classical signs of physeal injury with pain being potentially less intense [36]. Physeal injuries occur in 15% of children with fractures, and 10% of all physeal injuries are sport-related [36].

Gerstenfeld et al [44] summarized five key points of damaged epiphyseal plate healing that needs to be considered clinically. First, the anatomic structure of callus formation as it progresses during the healing phases should be considered [44]. Second, morphogenetic signals that facilitate the repair process should be known [44]. Third, and of importance for clinicians, is the role of the biomechanical aspect in controlling differentiation during cellular repair [44]. Fourth, the role of key groups of soluble factors i.e. pro-inflammatory cytokines and angiogenic factors during repair are important for establishing vascularity [44]. Finally, knowledge and appreciation for the relationship between the genetic components that control bone mass and remodeling is warranted [44]. These five key points should be acknowledged clinically in an effort to monitor for proper healing post-injury to the epiphyseal plate. From these key points, one can gain an appreciation for not reducing sport activity but in the intensity of the sport activity during the high intense growth phases. For example, it is not uncommon to see adolescents training year-round in one specific sport without the ability to either rest during the off-season or enter another sport that may be different and/or less intense in the training. As well, prohibitions of negative training and in some cases, the prohibition of sports all together, are sometimes necessary to minimize the potential for injury [27].While sports are important for children, safety and prevention of needless injury should be considered.

Influence of Inactivity on the Epiphyseal Growth Plate

The second and arguably the least discussed aspect concerning the epiphyseal growth plate is the role inactivity may play on the growth plate. Given the current interest in and rising rates of child obesity such interest in the growth plate should be considered. One of the implicated culprits in the child obesity epidemic is the lack of physical activity. It is known that epiphyseal growth plate activity controls longitudinal bone growth and leads ultimately to adult height yet numerous disorders are characterized by retarded growth and reduced final height eitherhave their origin in altered chondrocyte physiology or display pathological growth plate changes secondary to other causes [45]. Physical activity may have a protective effect on the epiphyseal growth plate, however, very little research has been conducted on the role of inactivity on the epiphyseal growth plates. This is possibly due to the lack of clinically-related biomechanical problems that emanate from a lack of physical activity on the epiphyseal plates. In other words, there is a paucity of research in the form of case studies that has implicated a lack of physical activity as an etiology for epiphyseal growth plate injury. Despite this, one could hypothesize that physical inactivity would not serve as an effect mechanism of protection. Frost [5] observed this very phenomenon but noted that for an obese person the stronger muscles would put larger loads on bones to which bone physiology should respond by increasing bone strength even if non-mechanical factors are involved. Until further research is undertaken on the effects of inactivity on the growth plate, one can extrapolate such effects from the current literature on normal and excessive functioning that sedentarism may result in inadequate stimulation of the growth plate with a possible result of changed growth potential.

Nonetheless, the recent concern over the increasing incidence and prevalence of obesity as seen in children gives rise to concern for the normal growth process. As previously indicated,functioning growth hormone (GH) and insulin-like growth factor (IGF)-I are essential for normal growth [46]. However, obese children will typically grow at a normal rate despite the presence of low serum GH levels with leptin, insulin, and sex hormones working to locally activate the IGF system at the epiphyseal plate [46]. Serum leptin may play a biological role in regulating bone metabolism by increasing the proliferation and differentiation of osteoblasts in adults [47]. Phillip et al [46] found that an elevated level of leptin in obese children can affect the bone growth center and it may be that leptin also participates in growth without GH observed in obesity.

It may appear that, in some cases, genetic expression, through favorable conditions, can be maximally achieved throughout the entire period of growth [48]. In this instance, it is hypothesized that for harm to be placed on the growth plate or show delayed growth maturation at the epiphyseal growth plate for those children who are physically inactive, thecombination of genetic expression through unfavorable environmental and socioeconomic conditions may be the culprit in abnormal epiphyseal growth plate physiology. In other words,only through unfavorable conditions such as extreme poverty, lack of nutrition, and other entities will the genetic expression manifest itself for those children who are physically inactive.While it is known that load-bearing tissue, such as articular cartilage, will atrophy in the absence of mechanical forces [6], future investigation into the effects of a lack of load bearingthrough a lack of physical activity on the epiphyseal plate is warranted.

Conclusion

The epiphyseal growth plate is a dynamic entity. Growth is dependent not only on intrinsic factors such as hormones and other regulatory factors but on extrinsic factors. These extrinsic factors are based entirely on the biomechanical model. Exercise, a positive aspect for the epiphyseal growth plate needs to be moderated through carefully crafted activities especially during pubertal growth spurts. Obesity, a major problem among todays youth, can be attributed in part to a lack of exercise. Once activity is undertaken the potential for epiphyseal growth plate disturbances from too much activity may be a predisposing factor to growth plate dynamics. The effects of exercise on the epiphyseal growth plate needs further research to comprehend the entirety of this dynamic anatomical and physiological entity. Research in the area of the epiphyseal growth plate in some children who are sedentary needs to be addressed.

Authors Contributions

All authors contributed equally to the conceptualization, writing, and approval of the paper.

Competing Interests

The authors declare no competing interests.

How Far Would You Go to Get Taller? – Another Limb Lengthening Height Increase Article Expose

Me: I thought I would post just another well written article which I found from a quick internet search. In my searching from typing in easy terms  into google like “Bone stretching”, I come across articles and posts written everywhere about limb lengthening, and the social and psychological issues which being short and desiring to be taller. Some are well written ,and others are not. Occasionally I find an article that is very well written and and insightful, and can make you feel an emotional connection with the people talked about in the article. I thought this article that I found from the Details Magazine website was very well written so I wanted to copy and paste it as a repost. It is not one of the posts I write which shows another breakthrough in research, but I would guess a lot of the people who find this website are not interested in the mechanics of auxology and endocrinology. This post is a step back from the more technical stuff.

The article expose was found from the website for Details Magazine located HERE


HOW FAR WOULD YOU GO TO GET TALLER?

WHY AN INCREASING NUMBER OF VERTICALLY CHALLENGED MEN ARE SUBJECTING THEMSELVES TO EXCRUCIATINGLY PAINFUL LEG-LENGTHENING SURGERY.

BY ELISA LUDWIG AND PHOTOGRAPH COURTESY OF DR. YASSER ELBATRAWY/LENGTHENING.NET

Jeff’s career as an architect at a prestigious East Coast firm was taking off. At 26, he was successful and athletic, and he had no trouble meeting women. There was, however, one problem. Though it was imperceptible to friends and colleagues, Jeff (his name has been changed) was tortured by a sense that he had been born with the wrong body. Jeff was five feet six inches tall, and he was obsessed with his height—or his lack of it. “To the outside world I was extremely confident, but my height was always an insecurity,” he says.

He was bitter, too, pissed that his brother was blessed with five more inches. He resented having to wear lifts and get his pants hemmed an extra several inches, and having to smile when a girlfriend’s parents teased him about how they would have short grandchildren. Most of all, Jeff hated the feeling of hopelessness that had dogged him ever since he stopped growing at age 17, a malaise no amount of positive talk or professional success could alleviate.

It was late one night five years ago that Jeff saw a segment on TV about limb-lengthening surgery in China. The report detailed a procedure called the Ilizarov method, in which a cagelike apparatus is attached to each leg and patients turn a set of screws to stretch their own bones. Jeff was fascinated, but he ultimately concluded that the procedure was too barbaric to consider seriously.

Then, about a year ago, Jeff came across a posting on an online message board about a “miracle” surgery at the Betz Institute, in Lebach, Germany—an advanced procedure that promised to make him almost four inches taller (most lengthening procedures guarantee only about two inches) with far fewer health risks. Instead of attaching an external cage, it involved implanting stretching devices inside his legs. He’d still be effectively crippled for months, but he wouldn’t need a wheelchair, just crutches. After three months of deliberating, Jeff flew to Germany to meet with Dr. Augustin Betz.

At the institute, Jeff saw postoperative patients looking happy and healthy. Most had gained between three and four inches in height. And all had good things to say about Dr. Betz. One even called the procedure “no big deal.” So Jeff broke up with his girlfriend—he’d always felt she held his height against him anyway—sold his car, liquidated some investments, borrowed money from his parents (the only people who knew about the plan), and took a leave of absence from work. He told his friends he would be doing an internship abroad for the next several months.

In Germany, Jeff’s femurs (thighbones) were severed by a surgical saw. The surgeon inserted a rodlike telescoping implant in the bone canal of each leg, bridging the cut. He fastened each rod in place with four pins. The next morning Jeff stood up on his new legs and took a few steps on crutches.

Continued (page 2 of 4)

He spent seven days in the hospital and the next 10 weeks, the lengthening phase, at a nearby residence. After the surgery, a sticky blood mass called a callus—the beginning of new bone—formed on each of his broken femurs. Jeff’s job was to click a remote control that signaled the rod to telescope out one millimeter a day, stretching the bone callus with it. He describes the feeling in pubescent terms, as “an intense growth spurt.” Then, during his last six to eight weeks in Germany, he waited for the bone to knit together and harden in its new, longer form.

Jeff is one of an estimated 4,000 people in the world who have chosen to undergo cosmetic limb lengthening (CLL) in recent years. “That number is increasing all the time,” says Dr. Dror Paley, an orthopedic surgeon at Sinai Hospital of Baltimore. Paley gets several e-mail inquiries about the procedure every day, the majority from affluent men between the ages of 20 and 40. “Some are very genuine,” he says, “and others are complete nutcases.”

A person could argue that to pay upwards of $100,000 for a risky, excruciating surgery that adds just a few inches to your frame is insane. CLL is by far the most extreme (and expensive) procedure that a human being can submit to in the name of vanity. Most lipo and facial-surgery patients can go home within an hour. Recovery time for calf and pec implants is a couple of weeks. And at $8,000, penile implants seem like a bargain by comparison—plus, in terms of pure physical pain, there is no contest. Beyond the agony of having your bones cut in two and stretched, CLL carries risks like pinhole infections, nerve damage, and severe deformity.

On a website called Make Me Taller, which launched two years ago, you can wade through message boards filled with self-loathing, hope, and hubris. “I would like to do 6 [centimeters] and go home sooner,” writes “12,” a patient about to undergo CLL in China. “I’ll have less possible complications and a shorter recovery time. The only thing that stops me from making that goal solid is the idea that I’ll be leaving almost an inch on the table. And yes, 2 inches is substantial, but isn’t 3 inches, like, mind-blowing?”

“What I hear is ‘People don’t take me as seriously as they would if I were taller,’” says Ellen Westrich, a psychologist who evaluates potential CLL candidates for Dr. S. Robert Rozbruch, a New York surgeon. “The dating [thing] is huge. In this culture, a certain value is placed on being taller than a woman, on being strong, being tall.” Some studies have shown that a man’s earning power and reproductive success correlate with his height. Add that information to the images of sad short-statured celebrities on shows like The Surreal Life and you can see why a man who stands well below the average American height of five feet ten deals with some very real misery.

Continued (page 3 of 4)

While most of the men Westrich screens are between five feet and five feet six, one in ten is over five eight, and some are significantly taller. At the Betz Institute, Jeff heard about a male model who left the clinic standing six feet two.

Some cases are more extreme than others. Before Akash Shukla had his surgery, he was four feet eleven and a half—not technically a dwarf but short enough to be mistaken for one. “People used to make a lot of jokes,” Shukla says. “I could never ask anyone out.” A 21-year-old engineering student from New Jersey, he took a year off from college to have CLL with Dr. Rozbruch. Six months and $200,000 later (that total includes expenses like equipment and physical therapy), he emerged standing five feet two. Though he says the surgery was “more painful than giving birth to seven children,” Shukla believes that the two and a half inches it gave him changed his life. “I have a new social confidence,” he says. He’s been approached by a number of men with questions about CLL—including a guy who was five feet eight. “I was like, ‘Oh my god, you’re actually considering cutting your bones in half to be five foot ten?’” Shukla says. “I’d give anything to be five foot eight.”

To save money, many CLL patients go to countries like Brazil, China, and Egypt, where the surgery, which isn’t covered by insurance, can cost as little as $10,000. Dr. Yasser Elbatrawy, an Egyptian surgeon, reports that 70 percent of his CLL patients come from North America; he says one was a recognizable Hollywood actor. “Some of these foreign surgeons are completely competent,” Paley says. “Others are doing it for mercenary reasons.”

And there are plenty of horror stories. On Make Me Taller, one former patient claims that he was abandoned during his lengthening procedure in Iran, shackled to an antiquated external leg-stretching device, and left with a handful of pain suppositories he had to self-administer. He returned to the United States with infections and his left leg bent at an odd angle; he was broke and near suicidal. “Tall or short, you are ugly when you limp and walk like a loser,” he writes in one post.

American doctors say they encounter cases like this regularly. “I just saw a guy who got lengthening on both tibias in the Ukraine,” Paley says. “He came back with infections, and surgeons had to shorten all the inches he’d gained. The guy still has a deformity.”

This spring, Jeff returned home from Germany. His life is, he insists, vastly improved. “The hardest thing is having to hide this,” he says. “I don’t want to be labeled as the guy that did limb lengthening.” The truth already came out with one buddy over drinks. But instead of meeting the news with ridicule, the friend, who is Jeff’s former height, was fascinated enough that he booked a flight to Germany to meet with Betz himself. “He saw my results and he’s pretty convinced,” Jeff says. Getting ready to return to work, Jeff has already bought a new wardrobe—including pants that have a 32-inch inseam. He can reach higher shelves without stretching or using a step stool. He imagines feeling the power of looking down at (or at least being eye-to-eye with) those who once towered over him. There will be new women to meet, as well—women who won’t give his height a moment’s thought. He’s also considering a career in stand-up comedy. Never mind that it was only a few inches; the way Jeff sees it, once you’ve freed yourself from the physical limits of your body, anything seems possible.

Continued (page 4 of 4)

“I’m not bitter anymore,” he says. “I’ll be a better father and husband and son. I just want to be the best person I can be.”

 

 

Testing Tissue Engineering Techniques On Goats With Coral Hydroxyapatite, CHAP And Bone Marrow Stromal Stem Cells, BMSCs

In me recent studying of using different types of tissue engineering ideas for bone defects ossification, I found two studies which I felt was worth really looking into to see how well two types of materials, the Coral Hydroxyapatite, CHAP and Bone Marrow Stromal Stem Cells, BMSCs will work in the healing of non-unions of bones. The previous post showed that the types of tissue engineered bone marrow stroma cells may not be that effective in being used for osteogeneis and/or bone healing.

Analysis & Interpretation

We see that these two studies are very similar to the article/study we looked at in the previous post since the same authors wrote these articles too. All of them are looking at the effectiveness of the coral hydroxyapatite (CHAP) and the bone marrow stroma stem cells (BMSCs).

From the 1st study, we see the same thing where only the CHAP and the BMSCs are being looked at for their effectiveness on the same type of bone defect, 2 cms. However in this study it seems that the researchers using the same type of bone formation measuring equipment noted that that the tissue engineering and the CHAP were effective after a few months. They conclude with “Tissue-engineered bone is capable of total repair of large bone defect in goats by forming normal functional new bones. CHAP can be eventually degraded completely and become the component of the newly generated bones.

From the 2nd study, I have only been able to get the abstract but still have been away to take away a few important parts. This study was similar but had a little more information which we can use for later research. the test animal were goats again. This time a 2.5 cm long defect was made to the middle of the right femur of the goats. What I would learn from this arbstract and study is that there should be two parts to the bone defect implant. If we imagine the bone defect being around 1 inch long, we realize we can’t just squeeze from type of stem cell into the bone layer and hope it will heal. There needs to be some type of scaffold or spongelike, porous, solid matrix material to hold the stem cells.

This is a lesson from tissue engineering research. For any type of implantation from grown/cultured cells, there has to be usually two parts to the implant.

1. The stem cells – For this study, we are looking at bone marrow stroma cells –

2. The medium for it to go into, or for this study, the coral hydroxyapatite – This is the matrix which the BMSCs are added into. The cells go into the empty cavities and line the inner walls of the matrix, and then the cells can interact with the cells of the surrounding natural tissues once the stem cell-scaffold is finally implanted.

The goats were actually broken up into two groups, the experimental and the control The control did have their femur also drilled with the same size of defect and had some other coral derivative added into the medium. The results showed that the MSCSs which are used to create bone with the CHAP matrix as a carrier did result in the bone healing almost properly after 4 months. The results showed that the two compounds worked well and the bones after healing was tested and had similar bone strength and rigidity as a bone which had not been drilled.

Implications For Height Increase

I think at this point it is clear that if we choose the distraction of bone idea, we would need to use the standard stem cell embedded into scaffold idea. Let’s remember that the coral hydroxyapatite is really just the non-organic, non-living mineral based element that makes the hard structure in our bone. Our bones have living and non living elements. The chondrocytes, stem cells, and such are living elements, cells. The nonliving elements are the proteins, the chemical compounds and elements, and the inorganic mineral stuff that make the bone. Bones get their hardness and have the matrix of the bone formed from the calcium derived hydroxyapatite. The researchers did note that this compound is great as a carrier/substrate because it can easily be resorbed by the bone system and leave almost a perfectly natural beone segment.

Let’s note that the stem cells which are supposed to be doing the real bone formation is the bone marrow stroma cells (BMSCs). The CHAP is used because it is so similar to the minerals already found in bone. The bonding is good and the human body doesn’t seem to reject it. This post shows us that the CHAP may be a very good candidate for a carrier/matrix element to be used in any proposed height increasing invasive implantation ideas.


From PubMed study 1 Long-term observation of large weight-bearing bone defect in goats repaired with tissue engineering technique

Nan Fang Yi Ke Da Xue Xue Bao. 2006 Jun;26(6):770-3. [Article in Chinese]  –  Chen B, Pei GX, Wang K, Tang GH.

Source – Department of Orthopedics and Traumatology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.

Abstract

OBJECTIVE:

To observe the long-term effect of tissue engineering-based repair of large weight-bearing bone defect in goats, and the final outcome of the scaffold material coral hydroxyapatite (CHAP) in vivo.

METHODS:

Fifteen Chinese goats were subjected to operations to induce a 2-cm left tibial diaphyseal defect, which was filled subsequently with CHAP and bone marrow stromal stem cells (BMSCs). The repaired defects were evaluated by ECT, X-ray and histology in the early stage and at 6, 12, 18, and 24 months postoperatively.

RESULTS:

ECT showed good bone regeneration and revascularization within 2 months postoperatively. X-ray and histology displayed eccentric and gradual bone regeneration in the early stage, and the tissue-engineered bone graft was firmly healed with the goat tibia. X-ray and histological examination at 6, 12, 18, 24 months postoperatively revealed moulding of the new bones and medullary cavity recanalization, and the structure of CHAP disappeared and gradually integrated into the new bones.

CONCLUSION:

Tissue-engineered bone is capable of total repair of large bone defect in goats by forming normal functional new bones. CHAP can be eventually degraded completely and become the component of the newly generated bones.

PMID:   16793597      [PubMed – indexed for MEDLINE]     Free full text 

From PubMed study 2 link Tissue-engineered bone repair of goat-femur defects with osteogenically induced bone marrow stromal cells.

Tissue Eng. 2006 Mar;12(3):423-33. –  Zhu L, Liu W, Cui L, Cao Y.

Source – Department of Plastic and Reconstructive Surgery, Shanghai Ninth People’s Hospital, Shanghai Tissue Engineering Center, Shanghai Second Medical University, Shanghai, China.

Abstract

Tissue engineering can generate bone tissue and has been shown to provide a better means of repairing weight-bearing bone defect. Previous studies, however, have heretofore been limited to the use of nonosteogenically induced bone marrow stromal cells (BMSCs) or the application of slow-degradation scaffolds. In this study, weight-bearing bone was engineered using osteogenically induced BMSCs. In addition, coral was used as a scaffold material, due to its proper degradation rate for the engineering and repair of a goat femur defect. A 25 mm long defect was created at the middle of the right femur in each of 10 goats. The rates of defect repair were compared in an experimental group of ten goats receiving implants containing osteogenically induced BMSCs and in the control group of goats (n = 10) receiving just coral cylinders. In the experimental group, bony union was observed by radiographic and gross view at 4 months, and engineered bone was further remodeled into newly formed cortexed bone at 8 months. There was increased gray density of radiographic rays in the repaired area, which was significantly different (p < 0.05) from that of the control group. H&E staining demonstrated that trabecular bone was formed at 4 months. Moreover, irregular osteon was observed at 8 months. Most importantly, the tissue-engineered bone segment revealed a similarity to the left-side normal femur in terms of bend load strength and bend rigidity, showing no significant difference (p > 0.05). In contrast, the coral cylinders of the control group showed no bone formation. Furthermore, almost complete resorption of the carrier had occurred, being evident at 2 months in the control group. H&E staining demonstrated that a small amount of residual coral particle was surrounded by fibrous tissue at 4 months whereas the residues disappeared at 8 months. Based on these results, we conclude that engineered bone from osteogenically induced BMSCs and coral can ideally heal critical-sized segmental bone defects in the weight-bearing area of goats.

PMID:   16579676     [PubMed – indexed for MEDLINE]

How To Accelerate Osteanagenesis And Revascularization Of Tissue Engineered Bone In Big Animals

This is a study that will help me to at least develop a better understanding on the type of ideas and surgical methods that might be needed to make bone healing be possible if any distractions made is too large.

Analysis & Interpretation

The paper is in Chinese so the translated version to English is not as clear for a native English reader to understand. The basic premise is that the researchers got a bunch of goats, put them in 3 groups, and drilled a 2 cm wide hole in the tibia of the goats. The holes are then added with three different types of materials for each of the 3 groups to see how well the material added will be in helping the natural bone heal. The three types of implants used are…

  1. Coral Hydroxyapatite (CHAP)
  2. Coral Hydroxyapatite & Bone Marrow Stroma Cells (BMSCs)
  3. Coral Hydroxyapatite & Bone Marrow Stroma Cells & fascia flap (whatever this is)

The results showed that the first two groups saw either no or little bone healing. The 3rd group showed that the bone defect at around 2 cm wide still maanged to heal almost completely.

Implications for Height Increase

This paper was unique because we are still looking at the best type of fast bone healing/osteogenesis material. There may come a point where we choose to go with the bone distraction idea and if that is done, the defects made could be dramatic and we would need to look for a tissue engineered mixture to heal large bone defects purposely induced. We see from this post that the compound fascia flap seems to have the ability to induce vascularization for bone healing.

From PubMed study The method of accelerating osteanagenesis and revascularization of tissue engineered bone in big animal in vivo


Zhongguo Yi Xue Ke Xue Yuan Xue Bao. 2003 Feb;25(1):26-31.

[Article in Chinese]

Chen B, Pei GX, Wang K, Jin D, Wei KH, Ren GH.
Source

Department of Orthopaedics and Traumatology, Nanfang Hospital, First Military Medical University, Guangzhou 510515, China. chb@fimmu.com

Abstract

OBJECTIVE:

To study whether tissue engineered bone can repair the large segment bone defect of large animal or not. To observe what character the fascia flap played during the osteanagenesis and revascularization process of tissue engineered bone.

METHODS:

9 Chinese goats were made 2 cm left tibia diaphyseal defect. The repairing effect of the defects was evaluated by ECT, X-ray and histology. 27 goats were divided into three groups: group of CHAP, the defect was filled with coral hydroxyapatite (CHAP); group of tissue engineered bone, the defect was filled with CHAP + bone marrow stroma cells (BMSc); group of fascia flap, the defect was filled with CHAP + BMSc + fascia flap. After finished culturing and inducing the BMSc, CHAP of group of tissue engineered bone and of fascia flap was combined with it. Making fascia flap, different materials as described above were then implanted separately into the defects. Radionuclide bone imaging was used to monitor the revascularization of the implants at 2, 4, 8 weeks after operation. X-ray examination, optical density index of X-ray film, V-G staining of tissue slice of the implants were used at 4, 8, 12 weeks after operation, and the biomechanical character of the specimens were tested at 12 weeks post operation.

RESULTS:

In the first study, the defect showed no bone regeneration phenomenon. 2 cm tibia defect was an ideal animal model. In the second study, group of CHAP manifested a little trace of bone regeneration, as to group of tissue engineered bone, the defect was almost repaired totally. In group of fascia flap, with the assistance of fascia flap which gave more chance to making implants to get more nutrient, the repair was quite complete.

CONCLUSIONS:

The model of 2 cm caprine tibia diaphyseal defect cannot be repaired by goat itself and can satisfy the tissue engineering’s demands. Tissue engineered bone had good ability to repair large segment tibia defect of goat. Fascia flap can accelerate the revascularization process of tissue engineered bone. And by this way, it augment the ability of tissue engineered bone to repair the large bone defect of goat.

PMID: 12905602     [PubMed – indexed for MEDLINE]