Zhou Jun, Que Yuhui, Pan Lihua, Li Xu, Zhu Chao, Jin Lai, Li Shengnan
Department of Pharmacology, Nanjing Medical University, Longmian Dadao 101, Nanjing, 211166, China.
Inflammation. 2022 Feb;45(1):356-371. doi: 10.1007/s10753-021-01551-7. Epub 2021 Sep 3.
Supervillin (SVIL) is an actin-binding and membrane-associated protein, which belongs to villin/gelsolin family. It has been reported that SVIL was involved in the regulation of macrophages' movement and lipopolysaccharide (LPS) increased the SVIL mRNA expression in neutrophils, but the underlying mechanisms remain unknown. This work investigated the underlying molecular mechanisms of LPS regulating SVIL expression in macrophages and hence the possible role of SVIL in LPS-induced inflammation. We found that in THP-1-derived macrophages, LPS obviously increased SVIL mRNA and protein expression. Inhibition of TLR4 by Resatorvid (Res) remarkably reversed the LPS-induced SVIL expression. Additionally, inhibition of ERK1/2 signaling pathway (by U0126 or GDC-0994) and NF-κB (by BAY) significantly reduced the LPS-induced SVIL expression. Interestingly, down-regulation of SVIL by SVIL-specific shRNAs significantly attenuated the expression of IL-6, IL-1β & TNF-α induced by LPS at both mRNA and protein levels. Furthermore, we also observed that SVIL knockdown decreased the proportion of cells in G/M phase and increased the proportion of cells in S & G phase of THP-1 derived macrophages, but did not influence the cell viability. Taken together, we demonstrated that LPS induced the expression of SVIL via activating TLR4/NF-κB and ERK1/2 MAPK pathways, and SVIL participated in the inflammatory response of LPS-induced IL-6, IL-1β and TNF-α upregulation in macrophages.
supervillin（SVIL）是一种肌动蛋白结合和膜相关蛋白，属于绒毛蛋白/凝溶胶蛋白家族。据报道，SVIL参与巨噬细胞运动的调节，脂多糖（LPS）可增加中性粒细胞中SVIL的mRNA表达，但其潜在机制尚不清楚。这项工作研究了LPS调节巨噬细胞中SVIL表达的潜在分子机制，以及SVIL在LPS诱导的炎症中的可能作用。我们发现，在THP-1衍生的巨噬细胞中，LPS明显增加了SVIL的mRNA和蛋白表达。Resatorvid（Res）对TLR4的抑制显著逆转了LPS诱导的SVIL表达。此外，抑制ERK1/2信号通路（通过U0126或GDC-0994）和NF-κB（通过BAY）显著降低了LPS诱导的SVIL表达。有趣的是，通过SVIL特异性shRNA下调SVIL在mRNA和蛋白水平上均显著减弱了LPS诱导的IL-6、IL-1β和TNF-α的表达。此外，我们还观察到，敲低SVIL可降低THP-1衍生巨噬细胞中G/M期细胞的比例，增加S期和G期细胞的比例，但不影响细胞活力。综上所述，我们证明LPS通过激活TLR4/NF-κB和ERK1/2 MAPK途径诱导SVIL表达，并且SVIL参与了LPS诱导的巨噬细胞中IL-6、IL-1β和TNF-α上调的炎症反应。
