Department of Occupational and Environment Health, Dalian Medical University, 9 W Lvshun South Road, Dalian, 116044, PR China.
Experimental Teaching Center of Public Health, Dalian Medical University, 9 W Lvshun South Road, Dalian, 116044, PR China.
Chem Biol Interact. 2019 Feb 25;300:123-130. doi: 10.1016/j.cbi.2019.01.019. Epub 2019 Jan 21.
The activation of hepatic stellate cells (HSCs) is a key event in the development of hepatic fibrosis caused by arsenic. However, it is unclear how arsenic induces the activation of HSCs. In the present study, we found that arsenic trioxide (AsO) induced liver tissue damage, stimulated autophagy and HSCs activation, and increased collagen accumulation in the liver of mice. Supplemented with taurine (Tau) attenuated the changes mentioned above caused by AsO. In human hepatic stellate cell line LX-2 cells, we found that AsO-induced activation of HSCs was autophagy-dependent, and we found that peroxisome proliferator activated receptors alpha (PPARα) played an important role in arsenic-induced HSCs activation. In addition, inhibiting autophagy and PPARα alleviated the activation of HSCs and lipid droplet loss induced by AsO. Moreover, we found that Tau alleviated AsO-induced elevation of autophagy and PPARα expression, and activation of the HSCs. Our results indicated that autophagy was regulated by PPARα and was involved in lipid droplet loss during the activation of HSCs. Tau alleviated AsO-induced HSCs activation by inhibiting the PPARα/autophagy pathway. These findings give an innovative insight into the association of PPARα, autophagy, the activation of HSCs and hepatic fibrosis induced by AsO.
肝星状细胞(HSCs)的激活是砷引起肝纤维化发展的关键事件。然而,砷如何诱导 HSCs 的激活尚不清楚。在本研究中,我们发现三氧化二砷(AsO)诱导肝组织损伤,刺激自噬和 HSCs 激活,并增加小鼠肝脏胶原的积累。用牛磺酸(Tau)补充可减轻 AsO 引起的上述变化。在人肝星状细胞系 LX-2 细胞中,我们发现 AsO 诱导的 HSCs 激活是自噬依赖性的,并且我们发现过氧化物酶体增殖物激活受体α(PPARα)在砷诱导的 HSCs 激活中起重要作用。此外,抑制自噬和 PPARα 可减轻 AsO 诱导的 HSCs 激活和脂滴丢失。此外,我们发现 Tau 减轻了 AsO 诱导的自噬和 PPARα 表达以及 HSCs 激活的升高。我们的结果表明,自噬受 PPARα 调节,并参与 HSCs 激活过程中的脂滴丢失。Tau 通过抑制 PPARα/自噬途径减轻 AsO 诱导的 HSCs 激活。这些发现为 PPARα、自噬、HSCs 激活以及 AsO 诱导的肝纤维化之间的关联提供了新的见解。