机构:[1]State Key Laboratory of Pharmaceutical Biotechnology, The University of Hong Kong, Pok Fu Lam, Hong Kong[2]Department of Medicine, The University ofHong Kong, Pok Fu Lam, Hong Kong[3]Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan University, Shanghai 20032, China[4]Beijing Key Laboratory of Diabetes Research and Care, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China首都医科大学附属北京同仁医院首都医科大学附属同仁医院[5]Department ofBiochemistry and Molecular Biology, University of Southern Denmark, Odense 5230, Denmark[6]Department of Molecular Medicine, Mayo Clinic, Rochester,Minnesota 55905, USA[7]Department of Pharmacology & Pharmacy, The University of Hong Kong, Pok Fu Lam, Hong Kong
Mitochondrial metabolism is pivotal for glucose-stimulated insulin secretion (GSIS) in pancreatic beta-cells. However, little is known about the molecular machinery that controls the homeostasis of intermediary metabolites in mitochondria. Here we show that the activation of p53 in beta-cells, by genetic deletion or pharmacological inhibition of its negative regulator MDM2, impairs GSIS, leading to glucose intolerance in mice. Mechanistically, p53 activation represses the expression of the mitochondrial enzyme pyruvate carboxylase (PC), resulting in diminished production of the TCA cycle intermediates oxaloacetate and NADPH, and impaired oxygen consumption. The defective GSIS and mitochondrial metabolism in MDM2-null islets can be rescued by restoring PC expression. Under diabetogenic conditions, MDM2 and p53 are upregulated, whereas PC is reduced in mouse beta-cells. Pharmacological inhibition of p53 alleviates defective GSIS in diabetic islets by restoring PC expression. Thus, the MDM2-p53-PC signalling axis links mitochondrial metabolism to insulin secretion and glucose homeostasis, and could represent a therapeutic target in diabetes.
基金:
Research Grants Council of Hong KongHong Kong Research Grants Council [17103614, C7055-14G]; National Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [81500624]; University of Hong KongUniversity of Hong Kong
第一作者机构:[1]State Key Laboratory of Pharmaceutical Biotechnology, The University of Hong Kong, Pok Fu Lam, Hong Kong[2]Department of Medicine, The University ofHong Kong, Pok Fu Lam, Hong Kong[3]Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan University, Shanghai 20032, China
共同第一作者:
通讯作者:
通讯机构:[1]State Key Laboratory of Pharmaceutical Biotechnology, The University of Hong Kong, Pok Fu Lam, Hong Kong[2]Department of Medicine, The University ofHong Kong, Pok Fu Lam, Hong Kong[7]Department of Pharmacology & Pharmacy, The University of Hong Kong, Pok Fu Lam, Hong Kong