Abstract:

Objective To study the transcriptional regulation of typeⅠprocollagen gene in systemic scleroderma （SS）-derived high collagen-producing fibroblast clones by Radix Salviae Miltiorrhizae （RSM）. Methods Fibroblast clones with different collagen-producing capacity were previously obtained from patients with SS and normal human controls, and divided into 5 groups to be treated with RSM （1 g/L） injection, its water-soluble active monomers including sodium danshensu （20 mg/L）, salvianolic acid B （5 mg/L） and protocatechuic aldehyde （5 mg/L）, and lipid-soluble active monomer （tanshinoneⅡA, 5mg/L） respectively. The fibroblast clones incubated with no drugs served as the water soluble negative control group, and those with dimethyl sulfoxide （DMSO） as the lipid soluble negative control group. MTT assay was performed to evaluate the proliferation of the fibroblast clones after 1-, 3-, 5-, and 7-day treatment, transient transfection and dual-luciferase reporter assay system to quantify the relative activity of collagen type I, alpha 1 （COL1A1） proximal promoter in these fibroblast clones. Results The inhibitory effect of RSM and its active monomers on the proliferation of fibroblast clones was inapparent within the initial 3 days （P > 0.05）, but was enhanced with incubation time. A significant difference was observed in the proliferation level of fibroblast clones between RSM group and water-soluble negative control group on day 5 （q′ ＝ 3.22, P < 0.01）, between RSM, salvianolic acid B, protocatechuic aldehyde groups and the water-soluble negative control group （q′ ＝4.74, 3.03, 2.56, all P < 0.05） on day 7, and between tanshinoneⅡA and lipid-soluble negative control group on day 5 and 7 （t = 2.22, 2.15, both P < 0.05）. RSM injection, tanshinoneⅡA and protocatechuic aldehyde significantly inhibited COL1A1 proximal promoter activity in SS-derived and normal control fibroblast clones （all P < 0.01）, and the former two drugs preferentially downregulated COL1A1 proximal promoter activity in SS-derived high collagen-producing fibroblast clones. Significantly different COL1A1 proximal promoter activity was observed in SS-derived high and low collagen-producing fibroblast clones between water-soluble negative control group and RSM injection group （12.019 ± 0.830 vs. 4.445 ± 1.061, 5.388 ± 0.480 vs. 2.856 ± 0.597, F ＝ 31.78, P < 0.01）, and between lipid-soluable negative control group and tanshinoneⅡA group （14.155 ± 0.672 vs. 9.638 ± 0.854, 4.299 ± 0.252 vs. 3.192 ± 0.450, F ＝ 24.10, P < 0.01）. Conclusions RSM inhibits the transcription of COL1A1 gene in SS-derived high collagen-producing fibroblast clones, which may be mainly attributed to tanshinoneⅡA and protocatechuic aldehyde.

Key words: Salviae miltiorrhizae