Exosomal microRNA-29a mediates cardiac dysfunction and mitochondrial inactivity in obesity-related cardiomyopathy

• DOI: 10.1007/s12020-018-1753-7
• Publication Date: 2018-09-27T16:08:12Z
• Authors: Fengqin Li; Kuikui Zhang; Ting Xu; Wenjuan Du; Bo Yu; Youbin Liu; Honggang Nie
• Keywords: Male; 2. Zero hunger; 0303 health sciences; Stroke Volume; Middle Aged; Diet, High-Fat; Exosomes; Mitochondria, Heart; Peptide Fragments; 3. Good health; Mice, Inbred C57BL; MicroRNAs; 03 medical and health sciences; Natriuretic Peptide, Brain; Animals; Humans; Obesity; Cardiomyopathies

Present study aims to explore the pathophysiological role of microRNA (miR)-29a in the process of obesity-related cardiomyopathy in human subjects and mice.The expression level of circulating exosomal miR-29a was measured in 37 lean and 30 obese human subjects, and correlated with cardiac parameters. The effects of miR-29a on mitochondrial activity and cardiac function were investigated by treatment of miR-29a sponge in primary mouse cardiomyocytes and diet-induced obesity-related cardiomyopathy in mice.The increased circulating miR-29a level was closely associated with impaired human cardiac function, including ejection fraction (r = -0.2663, p < 0.05) and NT-proBNP levels (r = 0.4270, p < 0.001). Exosomes from obese human plasma mediated cardiomyocyte mitochondrial inactivity, but pre-treatment with miR-29a sponge attenuated the exosomal miR-29a-induced reduction of ATP production (p < 0.001), basal oxygen consumption (p < 0.01) and mitochondrial complex I activity (p < 0.01). In vivo mouse study, high fat diet damaged cardiac function, normal structure, and mitochondrial activity, whereas miR-29a sponge improved the cardiac status.Present study uncovered the correlation between circulating miR-29a and cardiac parameters in human subjects, and provided solid evidence of the therapeutic application of miR-29a sponge in combating obesity-mediated cardiac dysfunction.