The Effects Of SAHA On TGF-β Induced Transformation Of Human Embryonic Lung Fibroblasts To Myofibroblasts

ObjectiveExplore the effects of the histone deacetylase inhibitors, suberoylanilide hydroxamicacid (SAHA) on the transforming growth factor-β1-induced differentiation of humanembryonic lung fibroblast cell line HELF cells to myofibroblasts (MF), and thusprovide a theoretical basis for the treatment of idiopathic pulmonary fibrosis (IPF).MethodsRats were divided into control group, TGF-β1group (5ng/mL) and SAHA groupswith different concentrations (0.5μM,2μM and5μM). HELF cells were cultured withthe combined stimulation of5ng/mL TGF-β1and5μM SAHA for24h. Then themorphological changes were observed before and after treatment, and explored theeffects of SAHA on the differentiation of HELF to MF. HELF-I cells were stimulatedwith TGF-β1for24h, then0.5,2,5μM SAHA was added and incubated for24h.MTT assay was used to detect cell proliferation, and Western blot was used to assessα-SMA expression, hydroxyproline content was determined in colorimetry, totalcollagen content and I, III procollagen mRNA expression were assessed by Sirius redstaining and by RT-PCR, respectively.Results1. Cells in the control group were elongated spindle, showing arc growth at a certaindegree, with large and nucleus, more into the center. In the effect of TGF-β1, the celldensity was significantly increased, swirling and radioactive growth. When HELFcells were incubated with5μM SAHA, their interval were widening, the protrusionshorten, and the cytoplasm decreased.2. After treated with TGF-β1, the proliferative activity of HELF cells was significantly increased. While treated with5μM SAHA, cell proliferation ratedecreased29.5%; the difference was statistically significant compared with TGF-β1group.3. Hydroxyproline expression was very low in the control group, while after TGF-β1treatment, the hydroxyproline content was significantly increased. When treated with0.5,2,5μM SAHA, hydroxyproline content reduced with the increase ofconcentration of SAHA.4.α-SMA expression almost couldn’t be detected in the control group. But with thetreatment of TGF-β1, the level of α-SMA was significantly increased, and SAHAcould also reduce α-SMA expression.5. The total collagen content was significantly higher in TGF-β1group. With treatedwith0.5,2,5μM SAHA, collagen content was increased with the reduction of dose6. After24h incubation of SAHA, mRNA expression of type I and type IIIprocollagen can be inhibited by stimulation of TGF-β1in dose-dependent manner.Conclusions:The differentiation and proliferation of HELF cells to MF induced by TGF-β1canbe inhibited by SAHA, it mainly manifested as growth inhibition, α-SMA andprocollagen expression.