肝星状细胞（HSC）负责肝纤维化，并伴有其活化成肌成纤维细胞和大量产生细胞外基质。然而，HSC 对肝脏炎症进展的贡献却鲜为人知。我们的目的是阐明 HSC 炎症反应的机制以及肿瘤坏死因子 α 相关蛋白 A20 (TNFAIP3) 的功能。我们通过 Twist2-Cre 和 A20 floxed 小鼠杂交建立了 A20 条件敲除 (KO) 小鼠。使用这些小鼠，分析了 A20 在小鼠肝脏和 HSC 中的作用。人 HSC 系 LX-2 也用于检查 A20 的作用和潜在分子机制。在此 KO 模型中，> 80% 的 HSC 中存在 A20 缺陷。在没有任何外源性药物的情况下，在小鼠模型的肝脏中发现了伴有轻度纤维化的自发炎症，这表明 HSC 中的 A20 可以抑制慢性肝炎。综合RNA序列分析显示，A20缺陷的HSC表现出炎症表型和异常表达的趋化因子。 A20 抑制 HSC 中 JNK 通路的激活。 LX-2 细胞中 A20 功能的丧失也会诱导趋化因子过度表达，类似于 A20 缺陷的 HSC。 A20 过表达抑制了 LX-2 中趋化因子的表达。此外，我们还发现了 A20 调控的基因中的 DCLK1。 DCLK1 激活 JNK 通路并上调趋化因子表达。 DCLK1 抑制显着降低 A20 沉默导致的趋化因子诱导，表明 A20 通过 DCLK1-JNK 途径控制 HSC 中趋化因子的表达。总之，A20 抑制依赖于 DCLK1-JNK 信号通路的趋化因子诱导。这些发现证明了 A20 和 DCLK1-JNK 通路在调节慢性肝炎炎症方面的治疗潜力。© 2024 美国实验生物学会联合会。

Hepatic stellate cells (HSCs) are responsible for liver fibrosis accompanied by its activation into myofibroblasts and the abundant production of extracellular matrix. However, the HSC contribution to progression of liver inflammation has been less known. We aimed to elucidate the mechanism in HSCs underlying the inflammatory response and the function of tumor necrosis factor α-related protein A20 (TNFAIP3). We established A20 conditional knockout (KO) mice crossing Twist2-Cre and A20 floxed mice. Using these mice, the effect of A20 was analyzed in mouse liver and HSCs. The human HSC line LX-2 was also used to examine the role and underlying molecular mechanism of A20. In this KO model, A20 was deficient in >80% of HSCs. Spontaneous inflammation with mild fibrosis was found in the liver of the mouse model without any exogenous agents, suggesting that A20 in HSCs suppresses chronic hepatitis. Comprehensive RNA sequence analysis revealed that A20-deficient HSCs exhibited an inflammatory phenotype and abnormally expressed chemokines. A20 suppressed JNK pathway activation in HSCs. Loss of A20 function in LX-2 cells also induced excessive chemokine expression, mimicking A20-deficient HSCs. A20 overexpression suppressed chemokine expression in LX-2. In addition, we identified DCLK1 in the genes regulated by A20. DCLK1 activated the JNK pathway and upregulates chemokine expression. DCLK1 inhibition significantly decreased chemokine induction by A20-silencing, suggesting that A20 controlled chemokine expression in HSCs via the DCLK1-JNK pathway. In conclusion, A20 suppresses chemokine induction dependent on the DCLK1-JNK signaling pathway. These findings demonstrate the therapeutic potential of A20 and the DCLK1-JNK pathway for the regulation of inflammation in chronic hepatitis.© 2024 Federation of American Societies for Experimental Biology.