Saisho Yoshifumi
Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.
Rev Diabet Stud. 2016 Summer-Fall;13(2-3):132-147. doi: 10.1900/RDS.2016.13.132. Epub 2016 Aug 10.
The pancreas is comprised of exocrine and endocrine components. Despite the fact that they are derived from a common origin in utero, these two compartments are often studied individually because of the different roles and functions of the exocrine and endocrine pancreas. Recent studies have shown that not only type 1 diabetes (T1D), but also type 2 diabetes (T2D), is characterized by a deficit in beta-cell mass, suggesting that pathological changes in the pancreas are critical events in the natural history of diabetes. In both patients with T1D and those with T2D, pancreas mass and exocrine function have been reported to be reduced. On the other hand, pancreas volume and pancreatic fat increase with obesity. Increased beta-cell mass with increasing obesity has also been observed in humans, and ectopic fat deposits in the pancreas have been reported to cause beta-cell dysfunction. Moreover, neogenesis and transdifferentiation from the exocrine to the endocrine compartment in the postnatal period are regarded as a source of newly formed beta-cells. These findings suggest that there is important interplay between the endocrine and exocrine pancreas throughout life. This review summarizes the current knowledge on physiological and pathological changes in the exocrine and endocrine pancreas (i.e., beta-cell mass), and discusses the potential mechanisms of the interplay between the two compartments in humans to understand the pathophysiology of diabetes better.
胰腺由外分泌和内分泌成分组成。尽管它们在子宫内起源相同,但由于外分泌胰腺和内分泌胰腺的作用和功能不同,这两个部分通常分开研究。最近的研究表明,不仅1型糖尿病(T1D),而且2型糖尿病(T2D)都以β细胞数量不足为特征,这表明胰腺的病理变化是糖尿病自然病程中的关键事件。据报道,T1D患者和T2D患者的胰腺质量和外分泌功能均降低。另一方面,胰腺体积和胰腺脂肪会随着肥胖而增加。在人类中也观察到随着肥胖程度增加β细胞数量增多,并且据报道胰腺中的异位脂肪沉积会导致β细胞功能障碍。此外,出生后从外分泌部分到内分泌部分的新生和转分化被认为是新形成的β细胞的来源。这些发现表明,内分泌胰腺和外分泌胰腺在一生中存在重要的相互作用。本综述总结了目前关于外分泌胰腺和内分泌胰腺(即β细胞数量)生理和病理变化的知识,并讨论了这两个部分在人类中相互作用的潜在机制,以更好地理解糖尿病的病理生理学。