Project description:In infection with an adenovirus, it remains to be clarified whether host miRNAs affect Ad replication. We focused on miR-27 as an miRNA crucial for regulation of Ad infection because miR-27 has been reported to be involved in infection of other viruses, including MCMV and herpesvirus saimiri (HVS). We used microarrays to detail gene expression profiles in miR-27a/b-overexpressing HeLa cells and demonstarted that expression levels of various genes were down- or up-regulated following transfection with miR-27a/b mimics.
Project description:Pancreatic β-cell dysfunction caused by obesity can be associated with alterations in the levels of microRNAs (miRNAs). However, the role of miRNAs in such processes remains elusive. Here, we show that pancreatic islet miR-27a-5p, which is markedly increased in obese mice and impairs insulin secretion, is mainly delivered by visceral adipocyte-derived extracellular vesicles (EVs). Depleting miR-27a-5p significantly improves insulin secretion and glucose intolerance in db/db mice. Supporting the function of EVs’ miR-27a-5p as a key pathogenic factor, intravenous injection of miR-27a-5p-containing EVs shows their distribution in mouse pancreatic islets. Tracing the injected AAV-miR-27a-5p (AAV-miR-27a) or AAV-FABP4-miR-27a-5p (AAV-FABP4-miR-27a) in visceral fat results in upregulating miR-27a-5p in EVs and serum, and elicits mouse pancreatic β-cell dysfunction. Mechanistically, miR-27a-5p directly targets L-type Ca2+ channel subtype CaV1.2 (Cacna1c) and reduces insulin secretion in β-cells. Overexpressing mouse CaV1.2 largely abolishes the insulin secretion injury induced by miR-27a-5p. These findings reveal a causative role of EVs’ miR-27a-5p in visceral adipocyte-mediated pancreatic β-cell dysfunction in obesity-associated type 2 diabetes mellitus.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.