m6A 去甲基化酶 FTO 通过靶向 SQSTM1/P62 调节自噬,从而预防坎格列净引起的肾纤维化。
m6A eraser FTO modulates autophagy by targeting SQSTM1/P62 in the prevention of canagliflozin against renal fibrosis.
机构信息
Chongqing University Central Hospital and Chongqing Emergency Medical Center, Chongqing, China.
School of Public Health, Medical College of Soochow University, Suzhou, China.
出版信息
Front Immunol. 2023 Jan 4;13:1094556. doi: 10.3389/fimmu.2022.1094556. eCollection 2022.
The dysregulation of autophagy contributes to renal fibrosis. N6-Methyladenosine (m6A) RNA modification is a critical mediator of autophagy. Our previous studies have reported that the disorder of the PPARα/fatty acid oxidation (FAO) axis in renal tubular cells is suppressed by STAT6, which is involved in the regulation of renal fibrotic processes. Here, we found that canagliflozin significantly upregulates SQSTM1/P62, promoting PPARα-mediated FAO by inducing autophagy-dependent STAT6 degradation both in TGF-β1-treated HK2 cells and in unilateral ureteral occlusion (UUO) and ischemia-reperfusion (I/R) renal fibrosis mouse models. Knockdown of P62/SQSTM1 led to the impairment autophagic flux and the dysregulation of the STAT6/PPARα axis, which was confirmed by SQSTM1/P62 mice with UUO treatment along with bioinformatics analysis. Furthermore, SQSTM1/P62 deficiency in renal tubular cells inhibited canagliflozin's effects that prevent FAO disorder in renal tubular cells and renal fibrosis. Mechanistically, the level of m6A eraser FTO, which interacted with SQSTM1 mRNA, decreased in the renal tubular cells both and after canagliflozin administration. Decrease in FTO stabilized SQSTM1 mRNA, which induced autophagosome formation. Collectively, this study uncovered a previously unrecognized function of canagliflozin in FTO in the autophagy modulation through the regulation of SQSTM1 mRNA stability in the renal tubular STAT6/PPARα/FAO axis and renal fibrosis.
自噬失调导致肾纤维化。N6-甲基腺苷(m6A)RNA 修饰是自噬的关键调节因子。我们之前的研究报告称,STAT6 抑制了肾小管细胞中 PPARα/脂肪酸氧化(FAO)轴的紊乱,该轴参与了肾纤维化过程的调节。在这里,我们发现坎格列净可显著上调 SQSTM1/P62,通过诱导自噬依赖性 STAT6 降解来促进 PPARα 介导的 FAO,这在 TGF-β1 处理的 HK2 细胞以及单侧输尿管梗阻(UUO)和缺血再灌注(I/R)肾纤维化小鼠模型中均得到证实。SQSTM1/P62 的敲低导致自噬通量受损和 STAT6/PPARα 轴失调,这通过 SQSTM1/P62 小鼠 UUO 处理以及生物信息学分析得到了证实。此外,肾小管细胞中 SQSTM1/P62 的缺失抑制了坎格列净预防肾小管细胞 FAO 紊乱和肾纤维化的作用。从机制上讲,与 SQSTM1 mRNA 相互作用的 m6A 橡皮擦 FTO 的水平在坎格列净给药后 和 均降低。FTO 的减少稳定了 SQSTM1 mRNA,从而诱导自噬体形成。总的来说,这项研究揭示了坎格列净在肾小管 STAT6/PPARα/FAO 轴和肾纤维化中通过调节 SQSTM1 mRNA 稳定性来调节自噬方面的以前未被认识到的功能。