Role of PVAT in obesity-related cardiovascular disease through the buffering activity of ATF3.

Thoracic aortic perivascular adipose tissue (PVAT) is an adipose organ exhibiting similarities to brown adipose tissue (BAT), including cellular morphology and thermogenic gene expression. However, whether the PVAT phenotype is indistinguishable from the BAT phenotype in physiological vasculature remains unclear. We demonstrated that PVAT is distinguishable from classical BAT, given its specific vessel-tone-controlling function. Activating transcription factor 3 (ATF3) is a key factor in hypertension. Compared with wild-type mice, ATF3-deficient (ATF3 -/- ) mice fed a high-fat diet exhibited elevated mean arterial pressure, increased monocyte chemoattractant protein-1 expression and hypertrophy, plus abnormal fatty tissue accumulation in the thoracic aortic PVAT, and enhanced vascular wall tension and vasoconstrictive responses of potassium chloride, U46619, and norepinephrine in isolated aortic rings, which were restored after administration of adeno-associated ATF3 vector. We suggest that PVAT, not BAT, modulates obesity-related vascular dysfunction. ATF3 within PVAT could provide new insights into the pathophysiology of obesity-related cardiovascular diseases.