Diabetes Mellitus is currently affecting more than 425 million people worldwide, among which over 90 % of the cases belong to type 2 diabetes. The number is growing quickly every year. Together with its many complications, the disease is causing tremendous social and economic burden and is classified as one of the leading causes of high morbidity and mortality rate. Residing in the islets of Langerhans, pancreatic beta cell serves as a central mediator in glucose homeostasis through secreting insulin, the only hormone that could reduce glucose level in the body, into the blood. Abnormality in pancreatic beta cell is generally considered as the fundamental reason which is responsible for the development of diabetes. Evidence shows that beta cell mass is greatly reduced in the biopsy of type 2 diabetic patients. Since then, large amount of research was conducted in order to decipher the molecular mechanisms behind the phenotype above and enormous progression has been made. The aim of this review is to summarize and provide a rudimentary molecular road map for beta cell mass reduction from the aspects of apoptosis and dedifferentiation based on recent research advances. Hopefully, this review could give the community some enlightenment for the next-step research and, more importantly, could provide avenues for developing novel and effective therapies to restrain or reverse beta cell loss in type 2 diabetes in the clinic.

糖尿病目前在全球影响超过4.25亿人，其中90％以上的病例属于2型糖尿病。这个数字每年都在快速增长。该疾病及其许多并发症引起巨大的社会和经济负担，被认为是高发病率和高死亡率的主要原因之一。胰岛β细胞位于Langerhans的胰岛中，通过将胰岛素（一种可以降低体内葡萄糖水平的唯一激素）分泌到血液中而充当葡萄糖稳态的主要调节剂。通常认为胰岛β细胞异常是导致糖尿病发展的根本原因。有证据表明，在2型糖尿病患者的活检中，β细胞量大大减少。自那以后，为了破译上述表型背后的分子机制，进行了大量的研究，并取得了巨大的进展。这篇综述的目的是基于最近的研究进展，从凋亡和去分化的角度总结并提供减少β细胞质量的基本分子路线图。希望这项综述可以为社区的下一步研究带来启发，更重要的是，可以为临床上开发出抑制或逆转2型糖尿病β细胞丢失的新型有效疗法提供途径。这篇综述的目的是基于最近的研究进展，从凋亡和去分化的角度总结并提供用于减少β细胞质量的基本分子路线图。希望这项综述可以为社区的下一步研究带来启发，更重要的是，可以为临床上开发出抑制或逆转2型糖尿病β细胞丢失的新型有效疗法提供途径。这篇综述的目的是基于最近的研究进展，从凋亡和去分化的角度总结并提供减少β细胞质量的基本分子路线图。希望这项综述可以为社区的下一步研究带来启发，更重要的是，可以为临床上开发出抑制或逆转2型糖尿病β细胞丢失的新型有效疗法提供途径。