Ventromedial hypothalamic lesions change the expression of cell proliferation-related genes and morphology-related genes in rat pancreatic islets.

Studies in normal rats and ob/ob mice indicated that islet neogenesis does not occur in the intact rodent pancreas. We previously reported that ventromedial hypothalamic (VMH) lesions stimulated cell proliferation of rat pancreatic islet B and acinar cells primarily through a cholinergic receptor mechanism and examined how gene families involved in cell proliferation in total pancreatic tissue are regulated after VMH lesions formation. This study examined how gene families involved in cell proliferation in pancreatic islets alone are regulated after VMH lesions formation. Pancreatic islet RNA was extracted, and differences in gene expression profiles between rats at day 3 after VMH lesioning and sham-VMH-lesioned rats were investigated using DNA microarray and real-time polymerase chain reaction. VMH lesions regulated genes that were involved in functions related to cell cycle and differentiation, growth, binding, apoptosis and morphology in pancreas islets. Real-time polymerase chain reaction also confirmed that gene expression of polo-like kinase 1 (Plk1) and topoisomerase (DNA) II α 170 kDa (Top2a), and stanniocalcin 1 (Stc1) were upregulated at day 3 after the VMH lesions. Ventromedial hypothalamic lesions may change the expression of cell proliferation-related genes and morphology-related genes in rat pancreatic islets.