Laboratory of Nervous System Development, Institute of Human Morphology, Moscow, Russia.
Laboratory of Nervous System Development, Institute of Human Morphology, Moscow, Russia.
Acta Histochem. 2019 Jul;121(5):638-645. doi: 10.1016/j.acthis.2019.05.010. Epub 2019 May 27.
In the human pancreas, various forms of endocrine cell arrangement are found: single endocrine cells, endocrine cell clusters, and mantel, bipolar and mosaic cell (mixed) islets. Our aim was to analyse the distribution and dynamics of insulin-, glucagon- and somatostatin-containing cells within the various forms of endocrine pancreas arrangement during human prenatal development and in adults and to suggest a mechanism of change in the endocrine cell ratio in adult islets. Pancreatic autopsies derived from human foetuses from the 10 to the 40 weeks of development and from adults were examined using histological, immunohistochemical and morphometric methods. During development, the human endocrine pancreas undergoes not only de novo differentiation of endocrine cells and islet formation, but morphogenetic restructuring, which is revealed as a change of the α-, β- and δ-cell ratio in the islets. In particular, increased proportion of glucagon- and somatostatin-containing cells and decreased proportion of β-cells were shown in the largest mosaic islets in adults. Our results indicate that the distribution and proportion of α-, β- and δ-cells depend on the islets size and vascularisation. Studying of the mechanism of such restructuring may contribute to the development of new approaches in the treatment of diabetes mellitus.
在人类胰腺中，存在着各种形式的内分泌细胞排列方式：单个内分泌细胞、内分泌细胞簇、套袖、双极和马赛克细胞（混合）胰岛。我们的目的是分析胰岛素、胰高血糖素和生长抑素分泌细胞在人类胚胎发育和成人不同形式的内分泌胰腺排列中的分布和动态，并提出成人胰岛内分泌细胞比例变化的机制。使用组织学、免疫组织化学和形态计量学方法检查了来自 10 周至 40 周发育的人类胎儿和成人的胰腺尸检标本。在发育过程中，人类内分泌胰腺不仅经历了内分泌细胞的新生分化和胰岛形成，还经历了形态发生重构，这表现为胰岛中α、β和δ细胞比例的变化。特别是在成人中，最大的马赛克胰岛中显示出胰高血糖素和生长抑素分泌细胞的比例增加，β细胞的比例减少。我们的结果表明，α、β和δ细胞的分布和比例取决于胰岛的大小和血管化。研究这种重构的机制可能有助于开发治疗糖尿病的新方法。
