Conclusion
Our results show a novel important role for endothelial c-Myc in regulating metabolic homeostasis and suggests its potential targeting in preventing obesity and associated complications such as diabetes type-2 and cardiovascular dysfunction.
Methods
We used conditional knockout (EC-Myc KO) and overexpression (EC-Myc OE) mouse models to investigate the endothelial-specific role of c-Myc in metabolic homeostasis during aging and high-fat diet exposure. Body weight and metabolic parameters were collected over time and tissue samples collected at endpoint for biochemical, pathology and RNA-sequencing analysis. Animals exposed to high-fat diet were also evaluated for cardiac dysfunction.
Results
In the present study we demonstrate that EC-Myc KO triggers endothelial dysfunction, which precedes progressive increase in body weight during aging, under normal dietary conditions. At endpoint, EC-Myc KO animals showed significant increase in white adipose tissue mass relative to control littermates, which was associated with sex-specific changes in whole body metabolism and increase in systemic leptin. Overexpression of endothelial c-Myc attenuated diet-induced obesity and visceral fat accumulation and prevented the development of glucose intolerance and cardiac dysfunction. Transcriptome analysis of skeletal muscle suggests that the protective effects promoted by endothelial c-Myc overexpression are associated with the expression of genes known to increase weight loss, energy expenditure and glucose tolerance.