Arteriolar Function in Visceral Adipose Tissue Is Impaired in Human Obesity

• Published in: Arteriosclerosis, thrombosis, and vascular biology Vol. 32; no. 2; pp. 467 - 473
• Main Authors: Farb, Melissa G., Ganley-Leal, Lisa, Mott, Melanie, Liang, YanMei, Ercan, Bahadir, Widlansky, Michael E., Bigornia, Sherman J., Fiscale, Antonino J., Apovian, Caroline M., Carmine, Brian, Hess, Donald T., Vita, Joseph A., Gokce, Noyan
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA American Heart Association, Inc 01.02.2012; Lippincott Williams & Wilkins
• Subjects: Adult; Arterioles - drug effects; Arterioles - physiopathology; Atherosclerosis (general aspects, experimental research); Bariatric Surgery; Biological and medical sciences; Blood and lymphatic vessels; Cardiology. Vascular system; Cardiovascular system; Diseases of the peripheral vessels. Diseases of the vena cava. Miscellaneous; Endothelium, Vascular - drug effects; Endothelium, Vascular - physiopathology; Female; Humans; Intra-Abdominal Fat - blood supply; Intra-Abdominal Fat - physiopathology; Investigative techniques of hemodynamics; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Middle Aged; Nitroprusside - pharmacology; Obesity - physiopathology; Obesity - surgery; Papaverine - pharmacology; Subcutaneous Fat - blood supply; Subcutaneous Fat - physiopathology; Vasodilator Agents - pharmacology; Vasomotor System - drug effects; Vasomotor System - physiopathology; Human; Obesity; adiposity; Adipose tissue; Nutrition disorder; arteries; Cardiovascular disease; Inflammation; Vasodilation; Endothelium; Vascular disease; Vasomotricity; Atherosclerosis; Nutritional status
• ISSN: 1079-5642; 1524-4636; 1524-4636
• DOI: 10.1161/ATVBAHA.111.235846

OBJECTIVE—The purpose of this study was to characterize the relationship between adipose tissue phenotype and depot-specific microvascular function in fat. METHODS AND RESULTS—In 30 obese subjects (age 42±11 years, body mass index 46±11 kg/m) undergoing bariatric surgery, we intraoperatively collected visceral and subcutaneous adipose tissue and characterized depot-specific adipose phenotypes. We assessed vasomotor function of the adipose microvasculature using videomicroscopy of small arterioles (75–250 μm) isolated from different fat compartments. Endothelium-dependent, acetylcholine-mediated vasodilation was severely impaired in visceral arterioles, compared to the subcutaneous depot (P<0.001 by ANOVA). Nonendothelium dependent responses to papaverine and nitroprusside were similar. Endothelial nitric oxide synthase inhibition with N-nitro-L-arginine methyl ester reduced subcutaneous vasodilation but had no effect on severely blunted visceral arteriolar responses. Visceral fat exhibited greater expression of proinflammatory, oxidative stress-related, hypoxia-induced, and proangiogenic genes; increased activated macrophage populations; and had a higher capacity for cytokine production ex vivo. CONCLUSION—Our findings provide clinical evidence that the visceral microenvironment may be intrinsically toxic to arterial health providing a potential mechanism by which visceral adiposity burden is linked to atherosclerotic vascular disease. Our findings also support the evolving concept that both adipose tissue quality and quantity may play significant roles in shaping cardiovascular phenotypes in human obesity.