Caspase-11/4 和 gasdermin D 介导的细胞焦亡导致糖尿病肾病小鼠足细胞损伤。
Caspase-11/4 and gasdermin D-mediated pyroptosis contributes to podocyte injury in mouse diabetic nephropathy.
机构信息
Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, 200032, China.
出版信息
Acta Pharmacol Sin. 2021 Jun;42(6):954-963. doi: 10.1038/s41401-020-00525-z. Epub 2020 Sep 23.
Diabetic nephropathy (DN) is characterized by sterile inflammation with continuous injury and loss of renal inherent parenchyma cells. Podocyte is an essential early injury target in DN. The injury and loss of podocytes are closely associated with proteinuria, the early symptom of renal injury in DN. However, the exact mechanism for podocyte injury and death in DN remains ambiguous. In this study we investigated whether pyroptosis, a newly discovered cell death pathway was involved in DN. Diabetic mice were generated by high-fat diet/STZ injections. We showed that the expression levels of caspase-11 and cleavage of gasdermin D (GSDMD-N) in podocytes were significantly elevated, accompanied by reduced expression of podocyte makers nephrin and podocin, loss and fusion in podocyte foot processes, increased inflammatory cytokines NF-κB, IL-1β, and IL-18, macrophage infiltration, glomerular matrix expansion and increased urinary albumin to creatinine ratio (UACR). All these changes in diabetic mice were blunted by knockout of caspase-11 or GSDMD. Cultured human and mouse podocytes were treated with high glucose (30 mM), which significantly increased the expression levels of caspase-11 or caspase-4 (the homolog of caspase-11 in human), GSDMD-N, NF-κB, IL-1β, and IL-18, and decreased the expression of nephrin and podocin. Either caspase-4 or GSDMD knockdown by siRNA significantly blunted these changes. In summary, our results demonstrate that caspase-11/4 and GSDMD-mediated pyroptosis is activated and involved in podocyte loss under hyperglycemia condition and the development of DN.
糖尿病肾病(DN)的特征是无菌性炎症,持续损伤和丧失肾脏固有实质细胞。足细胞是 DN 中早期损伤的重要靶点。足细胞的损伤和丧失与蛋白尿密切相关,蛋白尿是 DN 肾损伤的早期症状。然而,DN 中足细胞损伤和死亡的确切机制尚不清楚。在本研究中,我们研究了细胞焦亡这一新发现的细胞死亡途径是否参与了 DN。通过高脂肪饮食/STZ 注射生成糖尿病小鼠。我们发现,足细胞中 caspase-11 的表达水平和 gasdermin D(GSDMD-N)的裂解明显升高,同时伴有足细胞标记物nephrin 和 podocin 的表达减少,足细胞足突的丢失和融合,炎症细胞因子 NF-κB、IL-1β 和 IL-18 的增加,巨噬细胞浸润,肾小球基质扩张和尿白蛋白与肌酐比(UACR)增加。这些在糖尿病小鼠中的变化均因 caspase-11 或 GSDMD 的敲除而减弱。高糖(30mM)处理培养的人和鼠足细胞,显著增加 caspase-11 或 caspase-4(人类中 caspase-11 的同源物)、GSDMD-N、NF-κB、IL-1β 和 IL-18 的表达水平,并降低 nephrin 和 podocin 的表达。siRNA 敲低 caspase-4 或 GSDMD 均可显著减弱这些变化。总之,我们的结果表明,高糖条件下 caspase-11/4 和 GSDMD 介导的细胞焦亡被激活并参与了足细胞的丢失,从而导致了 DN 的发生。