血管紧张素Ⅱ诱导能量代谢重编程在足细胞损伤中的作用及机制

肾素血管紧张素系统(RAS)激活导致的足细胞损伤与慢性肾脏病(CKD)进展密切相关，但引起足细胞损伤的机制仍不明确。足细胞能量代谢(PEM)对于维持其生理功能至关重要，RAS激活是否改变PEM而导致足细胞损伤，缺乏系统研究。我们前期研究发现RAS的主要效应分子血管紧张素Ⅱ(AngⅡ)抑制足细胞糖酵解关键酶PKM2表达、减少ATP产生和促进足细胞凋亡。本项目拟研究RAS激活是否改变PEM而引起足细胞损伤及调控机制。通过对AngⅡ输注动物模型、双荧光报告小鼠原代培养足细胞、足细胞系、高血压肾损害患者肾活检标本的研究，评价PKM2表达和PEM改变与足细胞损伤的关系；通过PKM2质粒转染、PKM2激动剂、条件性PKM2敲除小鼠，探讨调控PKM2表达对足细胞糖酵解通量与足细胞损伤的影响。本研究旨在揭示RAS激活介导的PEM异常及其调控机制，为防治足细胞损伤及延缓CKD进展提供新的理论依据和治疗靶点。

Podocyte injury induced by activation of the renin-angiotensin system (RAS) is closely related to the progression of chronic kidney disease (CKD), but its mechanism remains unclear. The energy metabolism of podocytes is crucial to maintain its physiological function. However, whether RAS activation promotes CKD progression by changing podocyte energy metabolism has not been systematically elucidated. Our recent studies have found that Angiotensin Ⅱ (AngⅡ) as the main effector of the RAS, could significantly inhibit the expression of pyruvate kinase isozyme type M2 (PKM2), a key glycolytic enzyme, reduce the production of ATP, and induce apoptosis in podocytes. This project aims to unravel the regulatory mechanism of RAS activation-induced energy metabolic changes in podocyte injury. To evaluate the relationship between PKM2 expression, energy metabolism changes, and podocyte injury, we intend to construct the AngⅡ infusion animal model, establish the primary cell culture lines of podocytes using dual fluorescent protein reporter mouse, and analyze the renal biopsy specimens of patients with hypertensive nephropathy. Furthermore, the effects of PKM2 expression on glycolytic flux control and podocyte injury will be investigated by transfection with PKM2 plasmid, treatment with PKM2 agonist, and establishment of conditional PKM2 knockout mice. From the perspective of cell energy metabolism, this investigation will reveal RAS activation-induced energy metabolic dysfunctions and its molecular regulation mechanism, to provide a new theoretical basis and therapeutic target for the prevention and treatment of podocyte injury and CKD progression.