褪黑素抑制肝星状细胞增殖的机制研究

The mechanism of melatonin attenuates activation of hepatic stellate cells

目的通过转化生长因子-β1(TGF-β1)激活肝星状细胞系(HSC-T6),探讨褪黑素对活化的肝星状细胞系HSCT6的抑制作用及相关机制。方法肝星状细胞被分为5组,分别为:对照组、模型组和3个不同剂量实验组,培养24h贴壁后换用无血清培养基,除对照组外均加入TGF-β1,在实验组加入不同浓度的褪黑素,培养48 h后,通过MTT实验检测褪黑素对肝星状细胞增殖的影响,通过细胞免疫组化方法检测褪黑素对肝星状细胞中Smad蛋白表达的影响。结果与模型组相比,实验组中肝星状细胞的增殖明显被抑制(P<0.05);TGF-β1能明显刺激肝星状细胞中Smad2/3和p-Smad2/3的表达(P<0.01),与模型组比较,实验组可以明显抑制Smad2/3和p-Smad2/3的表达(P<0.05)。结论褪黑素可显著抑制肝星状细胞的增殖,其作用机制可能与抑制TGF-β1/Smad信号通路相关。

Objective To investigate the inhibitory effect of melatonin on TGF-β1-stimulated HSC-T6 cells and its underling mechanism. Methods The HSC-T6 ceils were divided into five groups： control group, model group and three experimental groups. After being cultured for 24 h, they were replaced with FBS-free medium and treated with transforming growth factor-β1 （TGF-β1, 5 ng/ml） excepted the control group, and melatonin was added im- mediately with different concentrations （ 1 nmol/L, 1 μmol/L, 0. 1 mmol/L） in three experimental groups. After drugs incubation for 48 h, MTF assay was performed to assess the cell proliferation, immunocytochemistry wereused to assess the expression levels of Smad2/3, p-Smad2/3. Results Melatonin could significantly inhibited cells proliferation simu]ating with TGF-β1 （ P 〈 0.05 ）. The expression of Smad2/3 and p-Smad2/3 in TCF-β1-treated group were dramatically elevated compared to the control group（ P 〈 0. 01 ）. After being added with different con- centrations of melatonin, the expression of Smad2/3 and p-Smad2/3 were strongly attenuated compared with the model group（P 〈 0.05 ）. Conclusion Melatonin significantly mitigates HSCs＇activation, which might be related to TGF-β1/Smad signaling pathway.