| Systemic sclerosis (SSc) is a connective tissue disease of unknown etiology in which the development of excessive and pathologic fibrosis process is prominent in the skin as well as in other internal organs. The treatment of it is difficult and remains a great challenge to the clinician. The failure of regulatory mechanisms that permit the balance between the amount of collagen synthesized and the amount of this protein removed from the tissue possessed by fibroblasts may be responsible for the excessive and frequently progressive accumulation of collagen in the tissue. In the present etiology study, the relationship between transforming growth factor (TGF- ) and abnormalities of procollagen metabolism in dermal fibroblasts from SSc was investigated. Equally important, in the therapeutics study, the effects of some Chinese Traditional Herbs and constituents of them on fibroblasts cell proliferation and type I and type III procollagen mRNA synthesis were studied.Firstly, primary cultures of fibroblasts were established from skin biopsies of affected areas from five patients with SSc and five normal persons (age- and sex- matched respectively) by standard tissue culture techniques. There were no apparent differences on biological characteristics between the fibroblasts from SSc and controls. The two groups had parallel cell generation time: latent phase was about 48 hours; logarithmic growth phase was about 48~96 hours; and stagnate phase was about 120~168 hours. Accordingly, total cell generations between SSc fibroblasts and nomal fibroblasts showed no significant difference, which were equally about 30 passages. In summary, the life span of skin fibroblasts from SSc was almost as same as normal strains, and did not show abnormally proliferation.Secondly, the relationship between TGF- and the expression of1( I ) procollagen (COL1A1 ) mRNA in dermal fibroblasts from SScwas investigated. The expression of COL1A1 mRNA was quantitativeassessed by in situ hybridization .Western Blotting was used to detect theproduction of TGF- in flbroblasts from both SSc and normal controls. The results show : The level of COLl Al mRNA are higher in flbroblasts from SSc(total optical density is 905.09 + 20.36) than in normal control(354.17 30.89) . Meanwhile, there were heterogeneity of COL1A1 mRNA distribution in both SSc and normal flbroblasts. The SSc flbroblasts had a larger proportion of cells in the high-COL1A1 mRNA-producing subpopulation(27.33 % 4.63%), compared with normal fibroblasts(3.67% 1.20%). On the other hand, within the low-COL1A1 mRNA-producing subpopulations, they had a dramatically smaller proportion of cells(14.33 % ?4.91%) than normal fibroblasts(62.33% ?.53%). Among SSc patients, the proportion of low, middle and high COL1A1 mRNA expressing flbroblasts was similar. TGF- production was similar between flbroblasts from patients with SSc and from normal controls. In summary, type I collagen mRNA synthesis was elevated in SSc flbroblasts, which may be uncorrected with the TGF- .Finally, in order to find effective antifibrotic Chinese Traditional Herbs and constituents of them, the effects of them on fibroblasts proliferation and the expressions of type I and type III procollagen mRNA were studied. At first, MTT test was used to study flbroblasts proliferation. Trypan blue staining and microscopic examination were taken to determine the median ineffective dose(ID50) of all tested drugs on fibroblasts. The flbroblasts were incubation for extending 1, 3, 6 days with those drugs of the tenth concentration of ID50- Among the aqueous extracts in herbs of Safflower, Red Peony Root(RPR), India Madder Root(IMR), Chinese Angelica(CA) and parenteral solution of Radix Salviae Miltiorrhizae(RSM), Safflower had the earliest suppression on cell proliferation at 24 hours, then RPR and IMR at 72 hours. Whereas, the RSM mildly stimulated cell proliferation before 24h, with more incubatin time, it showed inhibition at 72h. Different from them, CA had no effects on fibroblasts proliferation. Tanshinone II A, Danshensu...
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