Effects on Differentiation of Connective Tissue Cells

The phenomenon of scurvy, characterized by generalized defects in the extracellular matrices of bone, cartilage, and tendons, has prompted numerous attempts to define a role for ascorbate in metabolic processes crucial to the morphological and functional integrity of connective tissue. Since its role in the hydroxylation of collagen appeared not to explain satisfactorily all aspects of related deficiency symptoms (see Chapters 4 and 13), particular attention was paid to a potential involvement in the most complex differentiation processes leading from mesenchymal stem cells to mature connective tissue (Scutt et aL, 1992). 

In this section we shall review the various aspects of connective tissue differen- 

Similar events take place in postembryonic development during both endochondral longitudinal bone growth at the epiphysis and unstable fracture healing Cartilage is replaced by bone forming cells (Anderson, 1974). 

FIGURE 2. Simplified scheme of differentiation from mesenchymal precursors into mineralizing chondrocytes. The events stimulated by ascorbate are indicated by a short arrow. The numbers indicate the references identified as follows 1. Leboy et al, 1989 2. Tacchetti et al, 1987 3. Gerstenfeld and Landis, 1991 4. Shapiro et al., 1991 5. Habuchi et al., 1985. 

although vitamin C is not generally necessary for cell growth, it is essential for the synthesis of extracellular matrix components, the formation of a functionally correct architecture of the matrix, and matrix-dependent proliferation and differentiation. 

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