Inhibitory effects of oxymatrine on hepatic stellate cells activation through TGF-β/miR-195/Smad signaling pathway

Abstract

Background Oxymatrine (OM), a quinolizidine alkaloid extracted from a herb Sophorae Flavescentis Radix , has been used to treat liver fibrotic diseases. However, the mechanism of its anti-fibrosis effects is still unclear. TGF-β/Smad signaling and miR-195 have been proved to paly an important role in hepatic stellate cells (HSCs) activation and liver fibrosis. In this study, we investigated whether OM could inhibit HSCs activation through TGF-β1/miR-195/Smads signaling or not. Methods First, the effects of OM on HSC-T6 in different concentrations and time points were tested by MTT assay. We choose three appropriate concentrations of OM as treatment concentrations in following experiment. By Quantitative Real-time PCR and Western Blot, then we investigated the effect of OM on miR-195, Smad7 and α-SMA’s expressions to prove the correlation between OM and the TGF-β1/miR-195/Smads signaling. Last, miR-195 mimic and INF-γ were used to investigate the relation between miR-195 and OM in HSC activation. Results Our results showed that the proliferation of HSC was significantly inhibited when OM concentration was higher than 200 μg/mL after 24 h, 100 μg/mL after 48 h and 10 μg/mL after 72 h. The IC 50 of OM after 24, 48 and 72 h were 539, 454, 387 μg/mL respectively. OM could down-regulate miR-195 and α-SMA ( P < 0.01), while up-regulate Smad7 ( P < 0.05). In HSC-T6 cells transfected with miR-195 mimic and pretreated with OM, miR-195 and α-SMA were up-regulated ( P < 0.05), and Smad7 was down-regulated (P < 0.05) . Conclusions Given these results, OM could inhibit TGF-β1 induced activation of HSC-T6 proliferation in a dose-dependent and time-dependent manner to some extent. We proved that OM inhibited HSC activation through down-regulating the expression of miR-195 and up-regulating Smad7.

MicroRNA-195-5p Downregulation Inhibits Endothelial Mesenchymal Transition and Myocardial Fibrosis in Diabetic Cardiomyopathy by Targeting Smad7 and Inhibiting Transforming Growth Factor Beta 1-Smads-Snail Pathway

“…Consistently, we found that miR-195-5p can bind overexpression (Zhang et al, 2016). TGF-β1 increases α-SMA protein and decreases smad7 protein (Song et al, 2019). Collectively, silencing miR-195-5p inhibits EndMT by promoting smad7 expression.…”

“…Lentiviral delivery of smad7 in vivo results in an upregulation of CD31 and VE-cadherin and a downregulation of N-cadherin and vimentin, suggesting that EndMT is blocked in the pathological process of heterotopic ossification due to local smad7 overexpression ( Zhang et al, 2016 ). TGF-β1 increases α-SMA protein and decreases smad7 protein ( Song et al, 2019 ). Collectively, silencing miR-195-5p inhibits EndMT by promoting smad7 expression.…”

Targeting Hepatic Stellate Cells for the Treatment of Liver Fibrosis by Natural Products: Is It the Dawning of a New Era?

“…It was found that OM has an inhibitory effect on HSC-T6 cell line in vitro with concentration higher than 200 mg/ml after 24 h and 10 mg/ml after 72 h. miR-195, which is essential in HSC activation, was significantly down-regulated. SMAD7 level was augmented in the meantime (Song et al, 2019). Another study working on the LX-2 human HSC line has shown the possible mechanism of reducing procollagen I expression (Du et al, 2015).…”

Anticancer properties and mechanism of action of the quassinoid ailanthone

“…Certain natural products have the capacity to promote the expression of miR‐195 in cancer cells. This is the case of the tyrosol‐glucoside salidroside (Ren, Xu, & Xu, 2019) and schizandrin A (Kong, Zhang, Chu, & Wang, 2018), whereas in sharp contrast, the quinolizidine alkaloid oxymatrine downregulates miR‐195 (Song et al, 2019). AIT was found to upregulate significantly miR‐195 expression in A549 cells, thereby promoting autophagy and apoptosis of these lung cancer cells.…”