[Note: This is the 2nd post written by my collaborator on this project. She is a very welcome addition and it shows in her research and writing that she is very dedicated to the cause. Thanks Nicki.]

BMPS  and Growth

BMPS are most associated with BMPRs (Bone morphogenetic protein receptors). Defects in BMPS can lead to many skeletal disorders.  Other names for BMPS are CDMPS (cartilage derived morphogenetic proteins) and GDFS (growth differentiation factors). The family of BMPs is comprised of at least 15 members, which are all part of the TGFβ superfamily. BMPs were originally identified as stimulators of bone formation but are now recognized as important regulators of growth, differentiation, and morphogenesis during embryology.

Within the developing limb cartilage elements, BMP2, -4, and -7 have been detected in the perichondrium, whereas BMP6 was found in  prehypertrophic and hypertrophic chondrocytes.In addition, BMP7 was detected in chick sternal prehypertrophic and mice metatarsal proliferating chondrocytes.

The effects of BMPs are mediated by two type I receptors, BMPRIA and -IB, which heterodimerize with the type II receptor, BMPRII. The type I receptors are differentially localized in embryonic limbs; BMPRIB is detected in early mesenchymal condensations and is involved in early cartilage formation, whereas BMPRIA expression is confined to prehypertrophic chondrocytes.Constitutive active and/or dominant negative forms of BMPRIA and -IB revealed that the type IA receptor controls the pace of chondrocyte differentiation, whereas the type IB receptor is involved in cartilage formation and cell death (apoptosis).

Because various BMPs are expressed in chondrocytes, cartilage defects may be anticipated in BMP-related disorders in mice. Mice bred with homozygous null mutations in BMP2 and -4 are not compatible with life whereas other family members such as growth and differentiation factor 5 (GDF5) and BMP5 are important mediators of chondrocyte differentiation in mesenchymal condensations at various sites. In addition, mice carrying a targeted disruption of BMPRIB show defects in proliferation of prechondrogenic cells and chondrocyte differentiation in the phalangeal region.Additional BMPRIB/GDF5 and BMPRIB/BMP7 double knockout studies revealed that GDF5 is a ligand for BMPRIB and that in the absence of BMPRIB, BMP7 plays an essential role in appendicular skeletal development . In humans, only a few mutations in members of the TGFβ superfamily cause cartilage disorders. Genomic mutations in the human GDF5 gene have been shown to cause chondrodysplasia Grebe type, acromesomelic chondrodysplasia Hunter Thompson type, and brachydactyly type C, all of which are mainly characterized by defects of the limbs, with increasing severity toward the distal regions. Several mutations in the BMP antagonist noggin result in proximal symphalangism and multiple synostoses syndrome.

Recently, BMP6 was introduced as a possible mediator in the growth-restraining feedback loop involving Ihh and PTHrP. The fact that BMPRIA is expressed in the same region and that it has been shown to be critical for chondrocyte hypertrophy further strengthens an autocrine/paracrine role for BMP6 in prehypertrophic chondrocytes. Still, the BMP6 knockout mouse hardly has any phenotype, leaving little evidence for an important physiological role for BMP6 in chondrocyte differentiation. This was underscored by Minina et al. who elegantly showed that BMPs do not act as a secondary signal of Ihh to induce PTHrP expression or to delay the onset of hypertrophic differentiation. Despite this, they showed that normal chondrocyte proliferation requires parallel signaling of both Ihh and BMPs and that BMPs are capable of inhibiting chondrocyte differentiation independently of the Ihh/PTHrP pathway.

In another study, inhibition of chondrocyte differentiation by TGFβ was shown to be at least partly mediated by induction of PTHrP expression. In a second study by the same group, it was established that Shh, a functional substitute for Ihh, stimulates expression of TGFβ2 and -3 in mouse metatarsals and that TGFβ2 signaling is required for inhibition of differentiation and regulation of PTHrP expression by Shh. They concluded that TGFβ2 acts as a signal relay between Ihh and PTHrP in the regulation of chondrocyte differentiation . These data imply that the BMPs/TGFβ and their receptors act as a signaling system, both dependently and independently of the Ihh/PTHrP feedback loop, at different levels during embryonic bone formation.

Understanding BMPS

The roles of BMPs in embryonic development and cellular functions in postnatal and adult animals have been extensively studied in recent years. Signal transduction studies have revealed that Smad1, 5 and 8 are the immediate downstream molecules of BMP receptors and play a central role in BMP signal transduction. Studies from transgenic and knockout mice and from animals and humans with naturally occurring mutations in BMPs and related genes have shown that BMP signaling plays critical roles in heart, neural and cartilage development. BMPs also play an important role in postnatal bone formation. BMP activities are regulated at different molecular levels. Preclinical and clinical studies have shown that BMP-2 can be utilized in various therapeutic interventions such as bone defects, non-union fractures, spinal fusion, osteoporosis and root canal surgery. Tissue-specific knockout of a specific BMP ligand, a subtype of BMP receptors or a specific signaling molecule is required to further determine the specific role of a BMP ligand, receptor or signaling molecule in a particular tissue. BMPs are members of the TGFbeta superfamily. The activity of BMPs was first identified in the 1960s. “Bone formation by autoinduction”. but the proteins responsible for bone induction remained unknown until the purification and sequence of bovine BMP-3 (osteogenin) and cloning of human BMP-2 and 4 in the late  “Novel regulators of bone formation: molecular clones and activities”. “Purification and partial amino acid sequence of osteogenin, a protein initiating bone differentiation”. “The bone morphogenetic protein family and osteogenesis”.To date, around 20 BMP family members have been identified and characterized. BMPs signal through serine/threonine kinase receptors, composed of type I and II subtypes. Three type I receptors have been shown to bind BMP ligands, type IA and IB BMP receptors (BMPR-IA or ALK-3 and BMPR-IB or ALK-6) and type IA activin receptor.”Characterization and cloning of a receptor for BMP-2 and BMP-4 from NIH 3T3 cells”.”Identification of type I receptors for osteogenic protein-1 and bone morphogenetic protein-4″.”Specific activation of Smad1 signaling pathways by the BMP7 type I receptor, ALK2″. Three type II receptors for BMPs have also been identified and they are type II BMP receptor (BMPR-II) and type II and IIB activin receptors. “Osteogenic protein-1 binds to activin type II receptors and induces certain activin-like effects”. “Cloning and characterization of a human type II receptor for bone morphogenetic proteins”. “Cloning of a novel type II serine/threonine kinase receptor through interaction with the type I transforming growth factor-beta receptor”. Whereas BMPR-IA, IB and II are specific to BMPs, ActR-IA, II and IIB are also signaling receptors for activins. These receptors are expressed differentially in various tissues. Type I and II BMP receptors are both indispensable for signal transduction. After ligand binding they form a heterotetrameric-activated receptor complex consisting of two pairs of a type I and II receptor complex.”From mono- to oligo-Smads: the heart of the matter in TGFbeta signal transduction”.The type I BMP receptor substrates include a protein family, the Smad proteins, that play a central role in relaying the BMP signal from the receptor to target genes in the nucleus. Smad1, 5 and 8 are phosphorylated by BMP receptors in a ligand-dependent manner. “MADR1, a MAD-related protein that functions in BMP2 signaling pathways”,  “Smad5 and DPC4 are key molecules in mediating BMP-2-induced osteoblastic differentiation of the pluripotent mesenchymal precursor cell line. After release from the receptor, the phosphorylated Smad proteins associate with the related protein Smad4, which acts as a shared partner. This complex translocates into the nucleus and participates in gene transcription with other transcription factors. A significant advancement about the understanding of in vivo functions of BMP ligands, receptors and signaling molecules has been achieved in recent years. BMP signals are mediated by type I and II BMP receptors and their downstream molecules Smad1, 5 and 8. Phosphorylated Smad1, 5 and 8 proteins form a complex with Smad4 and then are translocated into the nucleus where they interact with other transcription factors, such as Runx2 in osteoblasts. BMP signaling is regulated at different molecular levels: Noggin and other cystine knot-containing BMP antagonists bind with BMP-2, 4 and 7 and block BMP signaling. Over-expression of noggin in mature osteoblasts causes osteoporosis in mice. Smad6 binds type I BMP receptor and prevents Smad1, 5 and 8 to be activated. Over-expression of Smad6 in chondrocytes causes delays in chondrocyte differentiation and maturation. Tob interacts specifically with BMP activated Smad proteins and inhibits BMP signaling. In Tob null mutant mice, BMP signaling is enhanced and bone formation is increased. Smurf1 is a Hect domain E3 ubiquitin ligase. It interacts with Smad1 and 5 and mediates the degradation of these Smad proteins. Smurf1 also recognizes bone-specific transcription factor Runx2 and mediates Runx2 degradation. Smurf1 also forms a complex with Smad6, is exported from the nucleus and targeted to the type I BMP receptors for their degradation. Over-expression of Smurf1 in osteoblasts inhibits postnatal bone formation in mice .

BMP-2 And Longitudinal Growth

Abstract

Bone morphogenetic proteins (BMPs) regulate embryonic skeletal development. We hypothesized that BMP-2, which is expressed in the growth plate, also regulates growth plate chondrogenesis and longitudinal bone growth. To test this hypothesis, fetal rat metatarsal bones were cultured for 3 days in the presence of recombinant human BMP-2. The addition of BMP-2 caused a concentration-dependent acceleration of metatarsal longitudinal growth. As the rate of longitudinal bone growth depends primarily on the rate of growth plate chondrogenesis, we studied each of its three major components. BMP-2 stimulated chondrocyte proliferation in the epiphyseal zone of the growth plate, as assessed by [3H]thymidine incorporation. BMP-2 also caused an increase in chondrocyte hypertrophy, as assessed by quantitative histology and enzyme histochemistry. A stimulatory effect on cartilage matrix synthesis, assessed by 35SO4 incorporation into glycosaminoglycans, was produced only by the highest concentration of BMP-2. These BMP-2-mediated stimulatory effects were reversed by recombinant human Noggin, a glycoprotein that blocks BMP-2 action. In the absence of exogenous BMP-2, Noggin inhibited metatarsal longitudinal growth, chondrocyte proliferation, and chondrocyte hypertrophy, which suggests that endogenous BMPs stimulate longitudinal bone growth and chondrogenesis. We conclude that BMP-2 accelerates longitudinal bone growth by stimulating growth plate chondrocyte proliferation and chondrocyte hypertrophy.

BMPS AND IHH /PHTrP INTERACTION

During endochondral ossification, two secreted signals, Indian hedgehog (Ihh) and parathyroid hormone-related protein (PTHrP), have been shown to form a negative feedback loop regulating the onset of hypertrophic differentiation of chondrocytes. Bone morphogenetic proteins (BMPs), another family of secreted factors regulating bone formation, have been implicated aspotential interactors of the Ihh/PTHrP feedback loop.To analyze the relationship between the two signaling pathways, we used an organ culture system for limb explants of mouse and chick embryos. We manipulatedchondrocyte differentiation by supplementing these cultures either with BMP2, PTHrP and Sonic hedgehog as activators or with Noggin and cyclopamine as inhibitors of the BMP and Ihh/PTHrP signaling systems. Overexpression of  Ihh in the cartilage elements of transgenic mice results in an upregulation of  PTHrP expression and a delayed onset of hypertrophic differentiation. Noggin treatment of limbs from these mice did not antagonize the effects of  Ihh overexpression. Conversely, the promotion of chondrocyte maturation induced by cyclopamine, which blocks Ihh signaling, could not be rescued with BMP2. Thus BMP signaling does not act as a secondary signal of Ihh to induce PTHrP expressionor to delay the onset of hypertrophic differentiation. Similar results were obtained using cultures of chick limbs.  We further investigated the role of BMP signaling in regulating proliferation and hypertrophic differentiation of chondrocytes and identified three functions of BMP signaling in this process. First we found that maintaining a normal proliferation rate requires BMP and Ihh signaling acting in parallel. We further identified a role for BMP  signaling in modulating the expression of Ihh. Finally, the application of Noggin to mouse limb explants resulted in advanced differentiation of terminally hypertrophic cells, implicating BMP signaling in delaying the process of hypertrophic differentiation itself. This role of BMP signaling is independent of the Ihh/PTHrP pathway.

We have identified several Ihh-independent functions of BMP signaling. One of these is to regulate the process of terminal hypertrophic differentiation. Blocking of BMP signaling by Noggin results in an increased number of  Osp-expressing, terminal hypertrophic cells. By contrast, cyclopamine treatment, which leads to an advanced onset of hypertrophicdifferentiation, does not increase  Osp expression. Double treatment experiments support the idea that BMP and

Analysis of mutations in single Bmp genes has not given significant insight into their role during skeletal differentiation. Targeted disruption of either Bmp2 or Bmp4 leads to early embryonic lethality (Winnier et al., 1995; Zhang and Bradley, 1996), whereas mutations in Bmp5, Bmp6 or Bmp7 only display mild skeletal phenotypes (Dudley et al., 1995; King et al., 1994; Kingsley et al., 1992; Luo et al., 1995; Solloway et al., 1998), indicating a highly redundantrole of Bmp genes in regulating bone development. In this study we have attempted to analyze the role of BMP signaling during chondrocyte maturation without differentiating between individual Bmp genes. As BMP proteins can substitute for each other in experimental systems, we have used BMP2 protein to mimic the role of several BMPs. Similarly, Noggin has been shown to inhibit signaling of various members of the BMP family (Zimmerman et al., 1996; Kawabata et al., 1998).  Several Bmp genes are expressed in specific regions of the developing cartilage elements and might thus be important for different aspects of chondrocyte differentiation during normal development.  Bmp7 is expressed in the proliferating chondrocytes distal to Ihh (Haaijman et al., 2000; Solloway et al., 1998) and may be responsible for regulating chondrocyte proliferation and Ihh expression. Other Bmps, including Bmp2, Bmp3, Bmp4 and Bmp7, are expressed in the perichondrium/ periosteum (Pathi et al., 1999; Zou et al., 1997; Daluiski et al.2001; Haaijman et al., 2000) .

Conclusion 

BMPs are the only molecules so far discovered capable of independently inducing endochondral ossification in vivo. TGF-b1 and TGF-b2 enhance the osteoinductive properties of BMPs; however, injection of TGF-bs on their own leads to extensive fibrous tissue formation only (Bentz, Armstrong & Seyedin, 1987). The mechanism of action of the BMPs has yet to be defined. However, the availability of recombinant forms has led to much work on their biological activity in vivo and in vitro. Recombinant forms of BMP2 and BMP4 induce ectopic bone formation, and BMP2 will heal cortical bone defects by an endochondral process (Hammonds et al., 1991; Wang, Rosen & Cordes, 1990; Yasko et al., 1992). BMP2 stimulates the growth and differentiation of growth plate chondrocytes in vitro, and results in the development of the osteoblast phenotype in a rat pluripotential cell line (Hiraki et al., 1991). Osteoblasts have been shown to have high affinity binding  proteins for BMP on the cell surface (Paralkar, Hammonds & Reddi, 1991).

Indirect lines of evidence demonstrate that BMPs have a critical role in bone development. Firstly, the protein encoded by the decapentaplegic locus (dpp) in Drosophila is a member of the TGF-b family member with 75% sequence homology to BMP2, suggesting a common ancestral gene. Developmental anomalies produced by mutations of the dpp gene are similar to patterns of disease expression in fibrodysplasia ossificans progressive, a developmental disorder characterised by deformations of the hands and feet and heterotopic chondrogenesis (Kaplan, Tabas & Zasloff, 1990). In addition, the chromosomal locations of the BMP genes overlap with the loci for several disorders of cartilage and bone formation (Tabas et al., 1991). More direct evidence is provided by a recent study which demonstrated that BMP2, together with fibroblast growth factor-4, is important in regulating limb growth in the mouse embryo (Niswander & Martin, 1993).

Me:: As you can see the group for Bone Morphogenetic Proteins (BMPs) is one of the most critical elements involved in the endochondral growth process. If I was to guess with the knowledge I have right now, I would move away from looking for way to increase GH release in the body but focus more on finding ways to get specifically the 20 discovered BMPs analyzed. The best way to start on that is to start on looking into BMP2, BMP5 and BMP7. My hypothesis is that the BMPs are the proteins that allow for the growth plates to run so efficiently for the chondrocytes to move form the proliferative layer to the ossification layer since there are two different processes going on right next to each other.

The parathyroid hormone-related protein (PTHrP) group is another possibility we need to study on because I have at least 3 papers so far showing that the Thyroid hormone proteins have been used as a template to create similar synthetic compounds used for bone growth. The other area to look into as well is the BMP2 inhibiting Noggin glycoprotein.

These days I am doing a lot of reading and research on sky’s old easyheight website and seeing what his methods were. Overall, I am starting to understand his approach and idea.

Sky was trying to use exercise and stretching methods to lengthen either the backbone/ lumbar area, the thigh bone, or the shin bone. He started the testing and work around 2003 and the site was around until 2011. He did not gain anything in terms of extra height. For all his passion, enthusiam, and belief, he didn’t grow taller. Why?

Here is my most educated guess. He was trying to increase his height using only exercise and stretching.

The big problem with Sky’s approach is that ever since humans evolved to the species that they are now, there has been estimated that there are over 100,000,000,000 humans. Of that 100 billion, that spans a time range of about 5 million years. In those 5 million years, there have been obviously many people who were “short” or have been considered short within the society they grew up and raised in. All these people probably wished at some point to be able to increase their height at some point.

Many of them when they were younger would have probably tried to increase their height using some “common sense” exercises. The biggest ideas are stretching, pulling the long bones, using gravity as a downward force like using inversion tables and hanging on a bar (even Michael Jordan did that). For the average person, not a real medical professional, those exercises seem reasonable in that they might be able to help increase height a little. The truth is that those exercises will increase height at least a little, but the increase is only temporary.

And throughout the 5 million years people have existed, not one person or group of people have found one method to be able to increase in height, at least through the ordinary exercise way. That was sky’s mistake. Why did he think he could discover a way to make the long bones elongate when so many other people before him couldn’t.

Let’s look at some of the most barbaric and tough civilizations that have existed.

1. Spartans- this society existed in creating super soldiers. Anything that resulted in stronger, bigger, and better fighting warriors was prized. They used to throw newly born babies down a cliff if the baby did not look healthy. This civilization would have trained their men and soldiers insanely hard to grow stronger. Even a person of average intelligence could ahve guessed that they probably also tried experiments to see if they could make their people taller too, for itimidation and war reasons. They failed to make their soldiers taller through all the training and exercises.

2. Aztecs- this civilization has gained a lot of infamy for taking slaves and war captures and sacrificing them by cutting out their hearts. The civilization was very brutal in the treatment of their bodies. I would guess that these people tried also to possibly grow taller from manipulating their bodies. THey were also a rather violent group of people who was almost always as war with other tribes. Being taller would have helped them look more intimidating and given them more of an advantage in battles. The failed to make their people bigger.

3. Japanese- During the 20th century the Japanese went into world war against the allied nations. If you have ever watched the old documentaries you coudl see that the young japanese children were forced to learn calisthenics, martial arts, stretch, and gymnastics to make their bodies taller and stronger so that they can be sent to the fornt lines and fight the othe nations. The Japanese knew during those times that they were much shorter than some other nations, especially the Americans who were the tallest nation during the 30s and 40s, and they were trying to get their young children to do exercises to match the height and size of the Americans they were fighting against. They never succeeded in creating a program to actually make the kids taller.

4. Chinese martists artists – In China’s 3000 year old tradition there has been thousands if not millions of martial arts experts, masters, etc. If you would guess anyone had better understanding of their own bodies and how to possibly grow taller, you would guess these types of people would have the best chance. So far, I have not heard of one martial arts master or ancient mythical fighter who was able to grow taller using some secret hidden technique they learned from a system of fighting. No one succeeded

5. Soviet scientists – The soviets were very famous for trying all sorts of bizzarre experiments on their own people to test the limits of what the human body was capable of. They used their own soldiers to take mind altering drugs and try out ancient meditation practices to see fi their military can learn to harness the old claims of ESP and psionic powers. It was one of these soviet scientists name Ilizarov through testing children and adult through brutal and painful experiments that discovered the world’s first real way to lengthen bones which gave us a real height increasing technique. Those types of experiments Ilizarov did to create his device would have never been allowed by the American medical community for how brutal and inhumane they treated their human patients and test subjects. Today, that type of human body experimentation would have been completely outlawed and he would be thrown in jail. I am almost positive that the Soviets also took their most brilliant of anatomists and asked them to look for ways to make their soldiers and people taller, again to show to the Americans that their way of thinking and society, running on the Communist ideas was better than the capitalist ways. Again, these brilliant soviet scientists could not find a way to increase the human height, at least just from exercise routines. One of them did succeed however in building a device with coupled with bone distraction surgery can increase a person’s height.

6. Chinese scientists – Like the soviets, the chinese scientists would have also tried at some point to try to develop some system to make their countrymen’s height increase. We have no idea what type of biological or chemiscal testing is being done by the chinese government right now. They could be testing on subjects for psionic and ESP powers just like the soviets did 40 years ago. They could also be testing exercise and surgical methods on subjects to try to make people taller too. So far, nothing in the chinese news have stated anything of big breakthroughs on the science of height increase yet.

My entire point from all these examples is to show that the way Sky was approaching the problem was exactly the same way billions of people before him who desired to achieve height increase also did. He thought a simple easy form of exercise routine which focused on tensile loading of the human leg long bones would be able to stretch the body out. Did sky realize that the human femur has a maximum tensile strength of 150 MPa? That strength of femur cortical bone is just at strong as steel. That’s right, steel!! It would make no sense that a person who can barely exert 500 lb/in^2 of power or even be able to rip up a phone book can possibly be able to use 30 lb ankle weights from repetitive kicking allow the bones of such high tensile strength to create enough microfractures to cause elongation.

Sky’s approach was wrong. We have seen that people from the past who were more dedicated than us, with more intelligence, more education, more time to do experiments and test on real humans, and more resources all fail in their endeavor to increase people’s height. Not one civilization in human history has been able to create a way to grow taller until the soviets through experimentation did create the ilizarov device, but they still had to use surgery and cut the bones in half first. There was no way sky using the small loads and the low rates that he did could have succeeded.

When I was doing my research to learn more about the detail of the growth plates and it’s subsections, I read that the chondrocytes creates a waste or output which is collagen and proteoglycan. I have already looked at the effects and possibilities of Collagen Type II on height and height increase in a previous article. Now in this post, I wanted to explore the affect and effects that proteoglycan has on human growth and height.

First, What is proteoglycans?

From the Medical Dictionary website (source HERE)…

proteoglycan /pro·teo·gly·can/ (pro″te-o-gli´kan) any of a group of polysaccharide-protein conjugates present in connective tissue and cartilage, consisting of a polypeptide backbone to which many glycosaminoglycan chains are covalently linked; they form the ground substance in the extracellular matrix of connective tissue and also have lubricant and support functions.

pro·te·o·gly·can (prt–-glkn, -kn) n. Any of various mucopolysaccharides that are bound to protein chains in covalent complexes and occur in the extracellular matrix of connective tissue.

proteoglycan [pro″te-o-gli´kan]

——->

For a further in depth detail, From Wikipedia (source HERE)…

Proteoglycans are proteins that are heavily glycosylated. The basic proteoglycan unit consists of a “core protein” with one or more covalently attachedglycosaminoglycan (GAG) chain(s). The point of attachment is a Ser residue to which the glycosaminoglycan is joined through a tetrasaccharide bridge (For example: chondroitin sulfate-GlcA-Gal-Gal-Xyl-PROTEIN). The Ser residue is generally in the sequence -Ser-Gly-X-Gly- (where X can be any amino acid residue), although not every protein with this sequence has an attached glycosaminoglycan. The chains are long, linear carbohydrate polymers that are negatively charged under physiological conditions, due to the occurrence of sulfate and uronic acid groups. Proteoglycans occur in the connective tissue.

Proteoglycans can be categorised depending upon the nature of their glycosaminoglycan chains. Proteoglycans can also be categorised by size (kDa).

Types

Types include:

Certain members are considered members of the “small leucine-rich proteoglycan family” (SLRP).^[3] These include decorin, biglycan, fibromodulin and lumican.

Function

Proteoglycans are a major component of the animal extracellular matrix, the “filler” substance existing between cells in an organism. Here they form large complexes, both to other proteoglycans, tohyaluronan and to fibrous matrix proteins (such as collagen). They are also involved in binding cations (such as sodium, potassium and calcium) and water, and also regulating the movement of molecules through the matrix. Evidence also shows they can affect the activity and stability of proteins and signalling molecules within the matrix. Individual functions of proteoglycans can be attributed to either the protein core or the attached GAG chain and serve as lubricants.

Synthesis

The protein component of proteoglycans is synthesized by ribosomes and translocated into the lumen of the rough endoplasmic reticulum. Glycosylation of the proteoglycan occurs in the Golgi apparatus in multiple enzymatic steps. First a special link tetrasaccharide is attached to a serine side chain on the core protein to serve as a primer for polysaccharide growth. Then sugars are added one at a time by glycosyl transferase. The completed proteoglycan is then exported in secretory vesicles to the extracellular matrix of the cell.

Proteoglycans and disease

An inability to break down proteoglycans is characteristic of a group of genetic disorders, called mucopolysaccharidoses. The inactivity of specific lysosomal enzymes that normally degrade glycosaminoglycans leads to the accumulation of proteoglycans within cells. This leads to a variety of disease symptoms, depending upon the type of proteoglycan that is not degraded.

ME: What is important to takeaway from this is that Proteoglycans (mucoproteins) are formed of glycosaminoglycans (GAGs) covalently attached to the core proteins. There are many types of glycosaminoglycans (GAGs). The most commonly well known GAGs are Hyaluronic acid, Dermatan sulfate, Chondroitin sulfate, Heparin and heparin sulfate, and Keratan sulfate (source HERE) 

From source http://www.cryst.bbk.ac.uk/pps97/assignments/projects/emilia/Proteoglycans.HTM

Structure of proteoglycans 

The GAGs extend perpendicular from the core protein in a bottlebrush- like structure.

The linkage of GAGs such as (heparan sulfates and chondroitin sulfates) to the protein core involves a specific trisaccharide linker :

The protein cores of proteoglycans are rich in Ser and Thr residues which allows multiple GAG attachment.

Role of proteoglycans and glycosaminoglycans

They perform numerous vital functions within the body.

GAG dependent functions can be divided into two classes: the biophysical and the biochemical.

The biophysical functions depend on the unique properties of GAGs : the ability to fill the space, bind and organize water molecules and repel negatively charged molecules. Because of high viscosity and low compressibility they are ideal for a lubricating fluid in the joints. On the other hand their rigidity provides structural integrity to the cells and allows the cell migration due to providing the passageways between cells.

For example the large quantities of chondroitin sulfate and keratan sulfate found on aggrecan play an important role in the hydration of cartilage. They give the cartilage its gel-like properties and resistance to deformation.

Aggrecan is one of the most important extracellular proteoglycans. It forms very large aggregates (a single aggregate is one of the largest macromolecules known ; it can be more than 4 microns long). Aggrecan molecules are non-covalently bound to the long molecule of hyaluronan (like bristles to the backbone in a bottlebrush). It is faciliated by the linking proteins. To each aggrecan core protein multiple chains of chondroitin sulfate and keratan sulfate are covalently attached through the trisaccharide linker .

The other, more biochemical functions of GAGs are mediated by specific binding of GAGs to other macromolecules, mostly proteins. Proteoglycans participate in cell and tissue development and physiology.

EXAMPLES OF GAG BINDING PROTEINS :

Secreted proteases and antiproteases

For example antithrombin III (AT III) binds tightly to heparin and certain heparan sulfates (so do its substrates). Thus they control the blood coagulation. In the absence of GAGs AT III inactivates proteases (such asthrombin, factors IXa and XIa) very slowly. In the presence of appropriate GAGs these reactions are accelerated 2000-fold.

GAGs are sufficiently long that both protease and protease inhibitor can bind to the same chain (thus the likelyhood of the two proteins binding to each other is increased enormously). GAGs also affect the protein conformation that contributes to improving AT III binding kinetics.

Polypeptide growth factors

Members of the FGF family, as well as several other growth factors, bind to heparin or heparan sulfate. Binding to endogenous GAGs entraps these molecules in ECM from which they may be later released. GAGs can alter the conformation, proteolytic susceptibility and biological activity of some of these proteins. The bound growth factor is resistant to degradation by extracellular proteases. Active hormone is released by proteolysis of the heparan sulfate chains. It occurs during the tissue growth and remodeling after infection.

One of the compounds that appear over and over again in my search was collagen, both type I and type II. If we remember, collagen is one of the compounds that the chondrocyte actually excrete (the other being proteoglycan) when they are still in the proliferate zone in the multilayer hyaline cartilage growth plate.

For most people, when they hear the word “collagen” they might think of collagen injections people get for plastic surgery to make their face look smoother and younger. Since I am currently living in a location of the world very famous for its plastic surgery clinics, I am very familiar with the use of collagen for plastic surgery reasons.

The first question to answer is “what is collagen type 2?”

From the Wikipedia article on it (HERE)…

Type-II collagen is the basis for articular cartilage and hyaline cartilage.

It makes up 50% of all protein in cartilage and 85-90% of collagen of articular cartilage.

Type II collagen does form fibrils. This fibrillar network of collagen allows cartilage to entrap the proteoglycan aggregate as well as provide tensile strength to the tissue.

Treatment of Rheumatoid Arthritis

According to a study published in the journal Science, oral administration of type II collagen improves symptoms of rheumatoid arthritis. The authors conducted a randomized, double-blind trial involving 60 patients with severe, active rheumatoid arthritis. A decrease in the number of swollen joints and tender joints occurred in subjects fed with chicken type II collagen for 3 months, but not in those that received a placebo. Four patients in the collagen group had complete remission of the disease. No side effects were evident.

Me: What the study seems to say is that collagen type 2 might have helped regenerate some lost articular cartilage at the ends of long bones or just in joints. Since the articular cartilage is made of 80-90% collagen type 2, it would kind of make sense that taking some type 2 collagen orally may indeed lead to some articular cartilage regeneration. Unfortunately, one of the most well known and accepted facts in the medical community is that unlike almost all other tissues, cartilage are not supposed to be able to regenerate back. This means the study for the treatment of rheumatoid arthritis and the results don’t agree with the non-regeneration of cartilage axiom held by mos tof the medical community. 

Note: It seems that while articular cartilage is 80-90% collagen type 2, for cartilage in general, specifically the hyaline cartilage in growth plates, it is only 50%. This seems to suggest the rest, the other 50% of proteins that form cartilage is from the proteoglycans. If that is true, I hypothesis that to keep the proliferation zone of the growth plate around longer, we should be taking something to help increase the proteoglycan in our bodies, not the collagen type 2!

Tyler at HeightQuest.Com already wrote an article on the idea HERE.

He states that “”…and if microfractures occur while the bone is in this stretched state it stands to reason that the bone will maintain some of this state.  If we can increase the collagen content of bone, then we should be able to put more of a distraction force on the cortical bone.  Microfractures will maintain some of this distracted state.””

From the paper he highlights, he concludes that “”Collagen is increased by Mesenchymal Stem Cells.  To increase collagen content in bone or the hyaline cartilage growth plate line then one needs to increase expression of the genes that control mesenchymal stem cell lineage(such as COL2A1 for hyaline cartilage).””

He continues to suggest that the other types of collagen (1, 9, 10) can all help in increasing height because they cause the mesenchymal stem cells to differentiate more into chondrocytes that hypertrophy.

I was again doing research for another article, specifically the one for the internal ISKD method and I started to wonder whether It was possible for the height increase researchers on here to develop a better biomedical device to be used to stretch out the long bones.

Here are all the types of medical devices out there right now, all used in the surgical method for limb lengthening. The resource used to find all this information below was from the Short Support Website located HERE

1. Albizzia is also called GEN for Gradual Elongation over intramedullary Nail and is a variation of Internal Lengthening Over Nails. The device is sping loaded. The rotation of the patient’s lower extremity creates the distraction with an audible “click.”

2. Bliskunov’s method

3. The Fitbone® device – the only device that uses a powered system to lengthen the legs. The bones of the leg (Tibia and/or Femur) are cut and the intramedullary telescoping nail is implanted in the bone marrow of each bone. Each end of the telescope nail is attached to each end of the cut bone. The nail is connected to an induction receiver that is placed just under the skin. An external control unit powers the telescope nail though the induction plate. A similar technique has been used to power artificial hearts.

4. Intramedullary Skeletal Kinetic Distractor (ISKD) – uses a kinetic clutch mechanism to lengthen the leg. One segment of a rod is screwed onto another and the whole rod is inserted into the patient’s bone. When the patient rotates his or her leg, the lower segment rotates over the upper one, like screwing a bolt out of a nut, and the rod lengthens, expanding the leg.

5. Lengthening Over Nails (LON) – a metal rod is inserted into the central cavity (intramedullary) of the lower legs (the tibia bone), and then the external fixator device is attached to the bone. As the limb is lengthened, one end of the bone slides over the rod and new bone is grown around it. When the bone is fully lengthened, the external device is removed and the rod is surgically attached to each bone segment. During bone strengthening, the rod provides support instead of the more uncomfortable and unwieldy External Fixator Device. At the end of the Strengthening phase, a second operation is performed to remove the metal rod.

6. Micro-wound – uses a fixative clip instead of an Ilizarov fixator. The fixator clip covers just one side of the leg and appears to be more comfortable than the Ilizarov fixator which completely surrounds the leg.

7. Precice™ – uses non-invasive adjustable intramedullary rods or bone plates to lengthen long-bones (e.g., femur, tibia). There are no open wounds. Lengthening is achieved through an External Remote Controller (ERC). The “ERC” is a portable, hand held unit that uses permanent magnets to automatically modify the length of the implant through the touch of a switch

8. Salamehfix – a hinged External Fixation System.  It is an arc system rather than a circular system and consists of three small arcs. The arcs are not the same diameter so the system can take the shape of leg. The entrance of screws and wires are in minimally painful regions so it’s more tolerable, provides for stable fixation and allows early full weight bearing. The small size of the system allows clothing to be worn over it with full mobility of nearby joints.

9. Original Ilizarov External Device

Me: It really is absolutely amazing to see what type of technology has been developed in the last 40 years ever since the Ilizarov fixator first came on the scene and allow people who had uneven limbs to get medical treatments fot their attention. Very quickly,  the short stature community realized the potential of this device and got the surgeons to use them to make people taller. 

Dr. Paley who has been doing the limb lengthening surgery for over 30 years now have come up with two big innovations on his own just from doing the surgeries and from experiences, seeing how they can be improved on.

In my opinion however ,the devices that are currently out can be made even better and improved on in the design. So far there is 9 different types of devices, but they all operate on the exact same type of principles. First, you cut open the bone you want to lengthen. Then you put something that can hold the two bones a small distance apart from each other. The bone ends starts to heal, and you slow move the bone parts further and further apart as the bones heal The bones thus increase. The muscles around them are also stretched out in the process. 

Getting back to the original issue, can we design a better device? I think we can. Here is my proposition.

The first principle to focus on is to make the device as non-invasive as possible. In my opinion, that means that after the bone has increased and healed it’s over, a quick trip to the doctor should mean the removal of the device and the bones will need little recovery after that.

The 2nd principle is to design a device that is strong but lightweight enough to hold up to the rigors of the limb bending and movement. The device can not collapse to the weight exerted on it by the human bones.

The 3rd principle is to create a design that can allow the full support of the leg. The leg MUST be completely fixed in place or the bones might turn or tiwst incorrectly leading to improper healing and the eventual bone regrowing into something crooked or stunted.

My idea for the device is a combination of the Microwound device used by Dr. Helong Bai and the Salamehfix device used by Prof. Ghassan Salameh. I will write up the new design in a future article. That however probably won’t come out for another 4-6 months, mainly because I want to study all of the devices that are out now and I haven’t done that yet.

This will be a complete step by step explanation of how the original ilizarov method and device was used to increase patients limbs. Remember that the soviet orthopedic surgeon was only intending to use it to help people with pathologies like stunted limbs so that they can live a more normal life. I wanted to post a picture to the right of the beginning of this post to show what exactly are the benefits and the liabilities of using the external fixator ilizarov method. It is noted right now that the picture shown on the right was taken from a Video I saw on Youtube, specifically entitled “Finite Element Analysis of Ilizarov External Fixator” which is located HERE. The pictures is not mine, but seems to come from a presentation given by the School of Mechanical, Aerospace, and Civil Engineering at the University of Manchester.

From Youtube Video from HERE is named “Beauty” which was on Season 7 Episode 1 of National Geocraphic’s website series called “Taboo”, from time range 15:00-25:00.

Everyday the bones are pulled apart so that they grow longer as they heal. The patient was named Margarita Rosam(n)ova gained about inch or slightly more, I guess 3-4 cm more in height). The surgery was performed by Dr. Constantin Navukov (spelling?) . It was done at the Illarov Clinic located in Kurgan of Siberia. The procedure was stated to cost $26,000 and the complications are infection, disability, and maybe also amputation. This type of surgery, as in all other types of surgery, there is no complete guarantee of success.

Note: during the entire operation, the patient of course will be put under with the strongest possible painkillers. If they don’t do that, the surgeons you choose to use may not be the best quality.

0. The patient is wheeled into the operations room where the usually team of surgeons and anesthesiologists will be. Their lower legs are first shaved of all hair to keep the operated on areas smooth. The lower legs are then dabbed/swabbed with alcohol for infection protection reasons. Then the operation really begins.

1. First, long wire metal spokes are drilled into the patient’s leg with an electric power drill. The area and bone which is almost always worked on is the lower leg part where the tibia and fibula are. The metal spokes go right through the bone and protrude from the skin onto the opposite side. This process of making holes is called perforation. The holes will make allow the surgeons to manufacture the fracture and achieve the results they want.

2. Each spoke is attached to either the top or bottom of the patient’s tibia or fibula bones. If they are not placed in the utmost precision, they might damage tissue or nerves. Usually there will be around 8-12 long metal spokes drilled through the two entire long bones, tibia and fibula. The spokes are first drilled in one direction, and the next one is drilled in another direction, about 60-90 degrees away from the first spoke. The exact location and direction on where to drill the thin metal spokes/ rods are really based on the human anatomy and bone positioning, which I don’t know at this time. I would assume any orthopedic surgeon would know EXACTLY what are the exact areas to drill into.

3. 3 of the spokes are usually drilled to the top of the tibia, 2, spokes drilled around the upper middle area of the tibia, and 2 are drilled around the lower middle area of the lower leg bones, and 3 spokes are drilled to the bottom of the tibia. Again, the exact location and direction of on how and where the spokes are drilled are not know to me at this time. I would assume there must be at least 2 spokes that also go through the fibula as well so that the fibula can extend too but I am not sure about that part. I am not sure about the exact number of spokes/drills there are supposed to be. In some videos and pictures I see less spokes used like around 8 and in others I see a lot more like around 12.

4. The surgeons then attach a metal brace called the Ilizarov frame, which is just two semicircular shaped metal pieces together, attaching the ends of the two pieces to form a thin circular ring which is about 2-3 mm thick and has a radial thickness of about 1 cm. In the metal semicircles, there are many holes on it equidistance positioned away from each other. The reason for the holes are for the poles and nuts to eventually go. Screw bolts or nuts or studs are used to close the ends.. The important thing is that the method allows the surgeons to keep all of the pieces and vitally important structures intact.

There is usually 8  semicircle metal pieces, that attach together to form 4 metal circles that will hold the spokes together and hold the legs into place.

5. The spokes are pruned at the ends for equal distance protruding from the leg. A rather larger piece of round plastic is pushing into the spokes, on both ends right next to there bone proferations are so they can hold the spokes into position. a piece of plastic goes right next to each bone/ skin protraction of spoke. The spokes is somehow attached to the circular metals by passing the thin spokes which look just like thick strong metal wires through a piece of strong plastic that is attached to the metal circle using screws which go through the holes.

The metal circles are then attached to each other through long and super long rod shaped screws. The shorter length screws are used to attach the circles on the edge of the lower leg regions to the circles closer to the middle. The really long rod shaped screws are the ones that hold the middle circles together. Of course, the ends of all screws are assumed to held into place with either strong plastic or lug nuts or bolts. If you can not picture what I am saying at this time, refer to the picture on the right.

6. With the frame in place, the surgeon then takes a chisel and a hammer. The chisel is inserted into the skin until it reaches contact with bone. While holding the chisel with one hand very steadily to one specific area in the tibia, the other hand swings the hammer at the tibia at a relatively strong force, in a tapping motion. The chisel acts similarly like a railway spike.

7. To avoid damaging the marrow in the inter medullary cavity, another surgeon works on the bone from the opposite side. The hammering in a steady but firm and strong tapping rate goes on usually for about 10 minutes until the chisel has made a clear fracture in the tibia, but only for the outer cortical bone area, not the inner cancellous (trabecular) bone part which should still be intact holding the marrow inside.

8. To check to make sure the proper fracture is made, the surgeons then get an X-Ray of the just operated on tibia bone. They want to make sure that both bones, the tibia and fibula are fractured.

9. Over the next few months in the futures, the gaps or fractures will be incrementally widened by turning screws on the long poles that have been used to hold the  inner metal circularly frames together. As the 4 screws are turned, the 4 poles used to hold circles together fixed in place will grow and extend longer. The bones will then grow longer to fill the gap.

10. The patient will be bed ridden for at least 4 months. The surgeons will come by on a regular basis to check up on the patient and to take measurements of the leg that is being lengthened. a baseline measurement of the leg is made. The frame will be slowly stretched. Usually the rods have only a set maximum amount of extension lengthening that is possible. Once the set lengthening is reached, the frames can be removed.

Eventually, the Frames are removed after about 4-6 months. The spokes are taken out.  There is still a lot of physical therapy that needs to be done. The newly formed leg bones may not be strong enough to hold up the patient so it takes a while. Since the spokes are pushing through the skin, the gradual lengthening and stretching of the bone also will touch the nerves and cause excruciating pain. The bone stretching may also tear the skin leaving scar marks.