Coordinated regulation of gene expression and microRNA changes in adipose tissue and circulating extracellular vesicles in response to pioglitazone treatment in humans with type 2 diabetes

Abstract

AbstractPioglitazone, a PPARγ agonist, is used to treat type 2 diabetes (T2D). PPARγ is highly expressed in adipose tissue (AT), however the effects of pioglitazone to improve insulin sensitivity are also evident in other tissues. We hypothesized that pioglitazone modifies the cargo of circulating AT-derived extracellular vesicles (EVs) to alter interorgan crosstalk. We tested this in a 3-month trial in which 24 subjects with T2D who were well-controlled with diet/exercise or metformin were randomized to treatment with either pioglitazone 45 mg/day or placebo (NCT00656864). Levels of 42 adipocyte-derived EV-miRNAs were measured in plasma EVs. Levels of 5 miRNAs (i.e., miR-7-5p, miR-20a-5p, miR-92a-3p, miR-195-5p, and miR-374b-5p) were significantly downregulated in EVs in response to pioglitazone treatment relative to placebo. However, the opposite occurred for miR-195-5p in subcutaneous AT from the same participants. Changes in miRNA expression in EVs and AT correlated with changes in suppression of lipolysis and improved insulin sensitivity, among others. DICER was downregulated and exosomal miRNA sorting-related genes YBX1 and hnRNPA2B1 displayed a trend toward downregulation in AT. Furthermore, analysis of EV-miRNA targeted genes identified a network of overtargeted transcripts that changed in a coordinated manner in AT. Collectively, our results suggest that some beneficial pharmacologic effects of PIO are mediated by adipose-specific miRNA regulation and exosomal/EV trafficking.Disclosure summaryThis study was funded by program funds granted to REP by the AdventHealth Translational Research Institute. The clinical trial was supported by an investigator initiated grant to REP from Takeda Pharmaceuticals North America. REP reports grants from Hanmi Pharmaceutical Co.; grants from Janssen; consulting fees from Merck; grants, speaker fees and consulting fees from Novo Nordisk; consulting fees from Pfizer; grants from Poxel SA; grants and consulting fees from Sanofi; consulting fees from Scohia Pharma Inc.; consulting fees from Sun Pharmaceutical Industries. AC reports consulting fees from GlaxoSmithKline. Honoraria and fees for REP’s and AC’s services were paid directly to AdventHealth, a nonprofit organization. No other potential conflicts of interest relevant to this article were reported.