We saw in a previous post Increase Height and Grow Taller Using Chondromodulin that a new type of glycoprotein recently learned about that has the ability to inhibit the formation of blood vessels aka vascularization in the chondrocyte area which might mean that it can at least slow down the ossification process of the chondrocytes leading to possible height increase. Let’s go slightly further into the analysis and see what can be found.
From study 1….
Chondromodulin-I which is a glycoprotein was identified as an angiogenesis inhibitor (ie. prevents the formation of blood vessels). ChM-I stimulated growth and colony formation of cultured chondrocytes. It is specifically expressed in the avascular zone of cartilage in developing bone, but not present in the late hypertrophic and calcified zones that allow vascular invasion. The researchers conclude with “It is what causes the angiogenic switching of cartilage, and that the withdrawal of its expression allows capillary in-growth, which triggers the replacement of cartilage by bone during endochondral bone development”
From study 2…
The researchers managed to isolate Chondromodulin II from bovine epiphyseal cartilage. Chondromodulin II stimulated the proteoglycan synthesis in rabbit cultured growth plate chondrocytes, an expression of the differentiated phenotype of chondrocytes. They also found another growth promoting factor with a higher herapin affinity, Chondromodulin III. It also stimulated DNA synthesis in chondrocytes in both the absence and the presence of fibroblast growth factor-2.
Implications
This new learned protein chondromodulin has been shown to stimulate proteoglycan synthesis and prevent vascularization so it is definitely another very important growth factor we will have to consider in our searching. It definitely does something in the regulation of the epiphyseal cartilage conversion to bone so it indirectly affects the longitudinal growth patterns.
From PubMed study 1 link HERE…
Pediatr Nephrol. 2000 Jul;14(7):602-5.
Chondromodulin-I as a novel cartilage-specific growth-modulating factor.
Source
Department of Molecular Interaction and Tissue Engineering, Institute for Frontier Medical Sciences, Kyoto University, Japan. hiraki@frontier.kyoto-u.ac.jp
Abstract
Cartilage is unique among mesenchymal tissues in that it is resistant to vascular invasion due to an intrinsic angiogenesis inhibitor. Chondromodulin-I (ChM-I), a 25-kilodalton glycoprotein purified from bovine epiphyseal cartilage on the basis of growth-promoting activity for chondrocytes, was recently identified as an angiogenesis inhibitor. Human ChM-I cDNA revealed that the mature protein consists of 120 amino acids and is coded as the C-terminal part of a larger transmembrane precursor. Expression of ChM-I cDNA in CHO cells indicated that mature ChM-I molecules were secreted from the cells after post-translational modifications and cleavage from the precursor protein at the predicted processing site. ChM-I stimulated growth and colony formation of cultured chondrocytes, but inhibited angiogenesis in vitro and in vivo. In situ hybridization and immunohistochemistry revealed that ChM-I is specifically expressed in the avascular zone of cartilage in developing bone, but not present in the late hypertrophic and calcified zones that allow vascular invasion. ChM-I actually inhibited vascular invasion into cartilage that was ectopically induced by demineralized bone matrix in nude mice, leading to the suppression of replacement of cartilage by bone in vivo. These results suggest that ChM-I participates in the angiogenic switching of cartilage, and that the withdrawal of its expression allows capillary in-growth, which triggers the replacement of cartilage by bone during endochondral bone development.
- PMID: 10912526 [PubMed – indexed for MEDLINE]
From PubMed study 2 link HERE…
J Biol Chem. 1996 Sep 13;271(37):22657-62.
A novel growth-promoting factor derived from fetal bovine cartilage, chondromodulin II. Purification and amino acid sequence.
Source
Department of Biochemistry and Calcified Tissue Metabolism, Osaka University Faculty of Dentistry, Osaka 565, Japan.
Abstract
During endochondral bone formation, cartilage cells show increased matrix synthesis and rapid proliferation. We found that cartilage matrix contains at least two types of heparin binding growth-promoting components. One, with a higher affinity to heparin, was identified as chondromodulin I (Hiraki, Y., Tanaka, H., Inoue, H. , Kondo, J., Kamizono, A., and Suzuki, F. (1991) Biochem. Biophys. Res. Commun. 175, 871-977). In this study, we isolated a novel growth-promoting component, chondromodulin II, which has a lower heparin affinity, from the dissociative extracts of fetal bovine epiphyseal cartilage. Chondromodulin II stimulated the proteoglycan synthesis in rabbit cultured growth plate chondrocytes, an expression of the differentiated phenotype of chondrocytes. It also stimulated DNA synthesis in chondrocytes in both the absence and the presence of fibroblast growth factor-2. The apparent molecular mass of chondromodulin II on SDS-polyacrylamide gel electrophoresis was 16 kDa. Its complete amino acid sequence was determined by overlapping sequences of the peptides released by endopeptidase digestion and CNBr cleavage. Chondromodulin II consists of 133 amino acids (calculated Mr = 14,548). The sequence was unique but homologous to the repeats 1 and 2 of the deduced amino acid sequence of the chicken mim-1 gene, which is specifically transactivated by the v-Myb oncogene product in promyelocytes. We also found a minor component with a higher heparin affinity, chondromodulin III, in cartilage extracts. Chondromodulin III stimulated DNA synthesis in chondrocytes in vitro, and its N-terminal sequence was identical with ribosomal protein L31 lacking the N-terminal three amino acids. These findings suggest that the growth and differentiation of chondrocytes are regulated by multiple components in the cartilage matrix.
- PMID: 8798437 [PubMed – indexed for MEDLINE] Free full text
