Reduced glutathione (GSH) could reduce oxidative stress to improve adipose tissue‐derived mesenchymal stem cell (ADSC) engraftment efficiency in vivo. However, the underlying mechanisms remain unclear. Our goal is to investigate whether GSH enhances ADSC engraftment through targeting the TGFβ/SMAD3/NOX4 pathway. Liver fibrotic male mice were administrated GSH, setanaxib (STX), and SIS3 during ADSC transplantation. ADSC engraftment efficiency and reactive oxygen species (ROS) level were detected both in vivo and ex vivo. Biochemical analysis was used to analyze the content of superoxide and nicotinamide adenine dinucleotide phosphate oxidases (NOXs) in liver tissues. Immunohistochemistry and western blotting were used to examine the protein level of NOX1, NOX2, NOX4, transforming growth factor‐β1 (TGFβ1), SMAD3, and p‐SMAD3 in liver tissues. Additionally, the therapeutic efficacy of the ADSC transplantation was further investigated. We found that GSH significantly improved ADSC engraftment efficiency, which was closely related to the reduced ROS generation in liver tissues. However, the enhanced cell engraftment was abolished after the combined treatment with STX or SIS3. GSH could effectively reduce superoxide and NOXs content, and selectively inhibit NOX4 expression in liver tissues. The co‐localization results showed that GSH could reduce NOX4 expressed in activated hepatic stellate cells. Mechanistically, GSH down‐regulated TGFβ/SMAD3 signaling. More importantly, GSH enhanced the therapeutic efficacy of ADSC therapy in liver fibrotic mice. Taken together, GSH could improve the engraftment efficiency of ADSCs in liver fibrosis by targeting TGFβ1/SMAD3/NOX4 signaling pathway, which provides a new theoretical basis for GSH enhancing ADSC engraftment efficiency in liver diseases.

中文翻译：

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还原型谷胱甘肽通过靶向 TGFβ1/SMAD3/NOX4 通路提高脂肪组织来源的间充质干细胞植入肝纤维化效率


还原型谷胱甘肽 （GSH） 可以减少氧化应激，从而提高脂肪组织来源的间充质干细胞 （ADSC） 体内植入效率。然而，潜在机制仍不清楚。我们的目标是研究 GSH 是否通过靶向 TGFβ/SMAD3/NOX4 通路增强 ADSC 植入。肝纤维化雄性小鼠在 ADSC 移植过程中给予 GSH 、 setanaxib （STX） 和 SIS3。体内和体外均检测 ADSC 植入效率和活性氧 （ROS） 水平。生化分析分析肝组织中超氧化物和烟酰胺腺嘌呤二核苷酸磷酸氧化酶 （NOXs） 的含量。免疫组化和蛋白质印迹法检测肝组织中 NOX1 、 NOX2 、 NOX4 、 转化生长因子-β 1 （TGFβ1） 、 SMAD3 和 p-SMAD3 的蛋白水平。此外，进一步研究了 ADSC 移植的治疗效果。我们发现 GSH 显着提高了 ADSC 植入效率，这与肝组织中 ROS 生成的减少密切相关。然而，在与 STX 或 SIS3 联合处理后，增强的细胞植入被消除。GSH 可有效降低超氧化物和 NOXs 含量，选择性抑制肝组织中 NOX4 的表达。共定位结果表明，GSH 可以降低活化肝星状细胞中 NOX4 的表达。从机制上讲，GSH 下调 TGFβ/SMAD3 信号传导。更重要的是，GSH 增强了 ADSC 疗法对肝纤维化小鼠的治疗效果。 综上所述，GSH 可通过靶向 TGFβ1/SMAD3/NOX4 信号通路提高肝纤维化中 ADSCs 的植入效率，这为 GSH 增强肝病中 ADSC 的植入效率提供了新的理论基础。