Jinyi Zhou, Yingying Shi, Lishuang Zhao, Rong Wang, Lan Luo, Zhimin Yin
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引用次数: 0
Abstract
Purpose: The impaired function of islet β-cell is associated with the pathogenesis of type 2 diabetes mellitus (T2DM). γ-glutamylcysteine (γ-GC), an immediate precursor of glutathione (GSH), has antioxidant and neuroprotective functions. Its level has been reported to be down-regulated in hyperglycemia. However, whether γ-GC has a protective effect on islet β-cell dysfunction remains elusive. Recently, we explore the molecular mechanism by which γ-GC protects islet β-cell from glucolipotoxicity-induced dysfunction.
Methods: In vivo mice models and in vitro cell models were established to examine the therapeutic effects and molecular mechanisms of γ-GC.
Results: db mice develop impaired glucose-stimulated insulin secretion (GSIS) due to reduced islet number and damaged islet microstructure. Serious oxidative damage, apoptosis and lipid accumulation are also observed in β-cell stimulated by glucolipotoxicity. Mechanistic studies suggest that glucolipotoxicity inhibits PDX-1 nuclear translocation by inducing endoplasmic reticulum (ER) stress, which leads to impaired insulin (INS) secretion in β-cell. Nevertheless, γ-GC as an inhibitor of ER stress can alleviate the damage of islet microstructure in db mice. Importantly, γ-GC promotes INS gene expression and GSIS through driving nuclear translocation of PDX-1, thereby enhancing intracellular INS content. Moreover, treatment with γ-GC can also mitigate oxidative damage, apoptosis and lipid accumulation of β-cell, resulting in ameliorating islet β-cell dysfunction induced by glucolipotoxicity.
Conclusion: Our results support the use of γ-GC as an inhibitor of ER stress for prevention and treatment of T2DM in the future.
期刊介绍:
Toxicology and Applied Pharmacology publishes original scientific research of relevance to animals or humans pertaining to the action of chemicals, drugs, or chemically-defined natural products.
Regular articles address mechanistic approaches to physiological, pharmacologic, biochemical, cellular, or molecular understanding of toxicologic/pathologic lesions and to methods used to describe these responses. Safety Science articles address outstanding state-of-the-art preclinical and human translational characterization of drug and chemical safety employing cutting-edge science. Highly significant Regulatory Safety Science articles will also be considered in this category. Papers concerned with alternatives to the use of experimental animals are encouraged.
Short articles report on high impact studies of broad interest to readers of TAAP that would benefit from rapid publication. These articles should contain no more than a combined total of four figures and tables. Authors should include in their cover letter the justification for consideration of their manuscript as a short article.