In his letter Dr. Bijur wrote:
>Is there anybody out there who knows if ascorbic acid (vitamin C) causes
>differentiation of fibroblasts. It has been established that ascobate does
>induce the synthesis of collagen. Indeed, do fibroblasts undergo
>differentiation? Differentiation of fibroblasts seems to be a confusing
>issue. There seems to be some confusion as to whether fibroblasts can
>undergo differentation like epithelial cells and lymphocytes. If there is
>anyone who has some insight into this process your help will be enormously
>Dept. of Med. Micro. Immunol.
>bijur.1 at pop.service.ohio-state.edu
Sorry, but something is wrong. Ascorbic acid does't induce the collagen
During collagen formation there are some posttranslational
modification occures. One of them is hydroxylation of some proline
residies in the chain giving 4- or 3-hydroxyproline.
Such a process is absolutely neccessary for collagen formation.
This hydroxylation is an enzymatic process and requers the presence
of ascorbic acid. Without vitamin C this reaction does't occur.
So, ascorbic acid does't affect collagen genes transcription, but
only give the ability to build normal, mature collagen.
So, the influence of vitamin C on collagen synthesis gives
no suggestion about fibroblast differentiation.
The different aspects of collagen biosynthesis are well
described in "Methods in Enzymology" v. 82, 1982.
Leonid A. Sadofiev
Institute of Cytology RAS