Periadventitial Adipose Tissue Promotes Endothelial Dysfunction via Oxidative Stress in Diet-Induced Obese C57Bl/6 Mice
Year: 2010
Type: article
Abstract: BACKGROUND: Biological substances derived from perivascular fat modulate vascular tone, thus alterations in periadventitial adipose tissue (PVAT) may aggravate endothelial dysfunction in obesity. METHODS AND RESULTS: Male C57Bl/6 mice were fed either a high-fat diet or standard laboratory chow for 8 months. Vascular responses were studied in organ bath chambers from abdominal aortic ring preparations in the absence or presence of PVAT. The amount of PVAT as well as the cross-sectional area of adipocytes were increased in obese mice. In the presence of PVAT, obese aortas displayed impaired endothelium-dependent vasodilation whereas endothelium-independent vasodilatation was unaltered. Endothelium-dependent vasodilatation was restored after removal of PVAT and after reducing superoxide and hydrogen peroxide formation in the vascular wall by Tiron or polyethylene-glycol-catalase, respectively. PVAT from obese mice showed increased formation of hydrogen peroxide and superoxide. The PVAT-derived oxidative stress was abolished by pretreatment with the reduced nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase inhibitor, apocynin. The anti-contractile function of PVAT found in lean mice was completely abolished in obese mice, but partially restored after pretreatment with Tiron. The mRNA expressions of monocyte chemotactic protein-1, leptin and NADPH oxidase were markedly higher in the PVAT of obese than lean mice. CONCLUSIONS: PVAT promotes endothelial dysfunction in diet-induced obese C57Bl/6 mice via mechanisms that are linked to increased NADPH oxidase-derived oxidative stress and increased production of pro-inflammatory cytokines.
Source: Circulation Journal
Authors: Juha Ketonen, Jin Shi, Essi Martonen, Eero Mervaala
Institutions: University of Helsinki, University of Eastern Finland
Language: English
Subfield: Cardiology and Cardiovascular Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W2074390557
