cis-4-Hydroxy-L-proline effects on skin

In a study, the effects of two proline analogues, cis-4-Hydroxy-L-prolineand L-azetidine-2-carboxylic acid, on the growth parameters and procollagen production by cultured normal human skin fibroblasts were examined. Several structural analogues of proline have been shown to be incorporated into proteins in place of proline.
The results indicated that incubation of the cells with the analogues reduced the rate of fibroblast proliferation and lowered the plating efficiency. Further experiments demonstrated that fibroblasts in the presence of L-azetidine-2-carboxylic acid synthesized procollagen polypeptides which were not in a triple-helical conformation, as judged by limited pepsin proteolysis. Also, a significantly increased fraction of the newly synthesized collagenous peptides was in a dialyzable form, suggesting increased degradation of the nonhelical chains.
The results suggest, therefore, that proline analogues may, in the future, prove useful in limiting excessive collagen deposition in scleroderma and other forms of dermal fibrosis.
cis-4-Hydroxy-L-proline