Cardiac-derived TGF-b1 confers resistance to diet-induced obesity through regulation of adipocyte size and function.

Regulation of organismal homeostasis in response to nutrient availability is a vital physiological process that involves inter-organ communication. Understanding the mechanisms controlling systemic cross talk for maintenance of metabolic health is critical to counteract diet-induced obesity. Here, we show that cardiac-derived transforming growth factor beta 1 (TGF-b1) protects against weight gain and glucose intolerance in mice subjected to high-fat diet. Secretion of TGF-b1 by cardiomyocytes correlates with bioavailability of this factor in circulation. TGF-b1 prevents adipose tissue inflammation independent of body weight and glucose metabolism phenotypes, suggesting protection from adipocyte dysfunction-driven immune cell recruitment. TGF-b1 alters gene expression programs in white adipocytes, favoring their thermogenic fate and consequently increasing their mitochondrial oxygen consumption rates. Ultimately, subcutaneous and visceral white adipose tissue from heart-specific TGF-b1 transgenic mice fail to undergo cellular hypertrophy, leading to reduced overall adiposity during high-fat feeding. Thus, TGF-b1 is a critical mediator of heart-fat communication for regulation of systemic metabolism. A total of four experimental groups with an n =3 were used as input for RNA-seq. The groups are wildtype and heart-specific over-expression of TGFbeta with either control or high fat diet treatment.