Guan Ruoqing, Xue Zhaoyun, Huang Kaikun, Zhao Yanqing, He Gongyun, Dai Yuxing, Liang Mo, Wen Yanzi, Ye Xueshi, Liu Peiqing, Chen Jianwen
National and Local United Engineering Lab of Druggability and New Drugs Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
Guangdong Province Engineering Laboratory for Druggability and New Drug Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
Pharmaceuticals (Basel). 2025 Jul 22;18(8):1080. doi: 10.3390/ph18081080.
: Oxidative stress constitutes a principal pathophysiological mechanism driving neurodegeneration and brain aging. α-Ketoglutarate (AKG), a key intermediate of the tricarboxylic acid (TCA) cycle, has shown potential in longevity and oxidative stress resistance. However, the role of AKG in oxidative stress-induced neuronal senescence and its interaction with the mTOR signaling pathway during neuronal aging remain poorly understood, posing a key challenge for developing senescence-targeted therapies. : We investigated the neuroprotective effects of AKG using HO-induced senescence in HT22 cells and a D-galactose-induced brain aging mouse model. Assessments encompassed SA-β-gal staining, EdU incorporation, mitochondrial membrane potential (JC-1), and ROS measurement. Antioxidant markers, ATP levels, and the NAD/NADH ratio were also analyzed. Proteomic profiling (DIA-MS) and KEGG/GSEA enrichment analyses were employed to identify AKG-responsive signaling pathways, and Western blotting validated changes in mTOR signaling and downstream effectors. : AKG significantly alleviated HO-induced senescence in HT22 cells, evidenced by enhanced cell viability, reduced ROS level, restored mitochondrial function, and downregulated p53/p21 expression. In vivo, AKG administration improved cognitive deficits and vestibulomotor dysfunction while ameliorating brain oxidative damage in aging mice. Proteomics revealed mTOR signaling pathways as key targets for AKG's anti-aging activity. Mechanistically, AKG suppressed mTOR phosphorylation and activated ULK1, suggesting modulation of autophagy and metabolic homeostasis. These effects were accompanied by enhanced antioxidant enzyme activities and improved redox homeostasis. : Our study demonstrates that AKG mitigates oxidative stress-induced neuronal senescence through suppression of the mTOR pathway and enhancement of mitochondrial and antioxidant function. These findings highlight AKG as a metabolic intervention candidate for age-related neurodegenerative diseases.
氧化应激是驱动神经退行性变和脑衰老的主要病理生理机制。α-酮戊二酸（AKG）是三羧酸（TCA）循环的关键中间产物，已显示出在延长寿命和抗氧化应激方面的潜力。然而，AKG在氧化应激诱导的神经元衰老中的作用及其在神经元衰老过程中与mTOR信号通路的相互作用仍知之甚少，这对开发针对衰老的治疗方法构成了关键挑战。
我们使用HO诱导HT22细胞衰老和D-半乳糖诱导的脑衰老小鼠模型研究了AKG的神经保护作用。评估包括SA-β-半乳糖染色、EdU掺入、线粒体膜电位（JC-1）和ROS测量。还分析了抗氧化标志物、ATP水平和NAD/NADH比率。采用蛋白质组学分析（DIA-MS）和KEGG/GSEA富集分析来鉴定AKG反应性信号通路，蛋白质印迹法验证了mTOR信号和下游效应器的变化。
AKG显著减轻了HO诱导的HT22细胞衰老，表现为细胞活力增强、ROS水平降低、线粒体功能恢复以及p53/p21表达下调。在体内，给予AKG改善了衰老小鼠的认知缺陷和前庭运动功能障碍，同时减轻了脑氧化损伤。蛋白质组学显示mTOR信号通路是AKG抗衰老活性的关键靶点。机制上，AKG抑制mTOR磷酸化并激活ULK1，提示对自噬和代谢稳态的调节。这些作用伴随着抗氧化酶活性增强和氧化还原稳态改善。
我们的研究表明，AKG通过抑制mTOR途径以及增强线粒体和抗氧化功能来减轻氧化应激诱导的神经元衰老。这些发现突出了AKG作为与年龄相关的神经退行性疾病的代谢干预候选物。
