Voluntary running prevents mesenteric endothelial dysfunction in high-fat diet-induced obesity through e-NOS and oxidative stress regulation

Background: Exercise alleviates obesity-associated vascular endothelial dysfunction, but its underlying mechanisms in the mesenteric artery remain underexplored. Therefore, this study aimed to investigate whether voluntary running prevents high-fat diet-induced endothelial dysfunction in the mesenteric artery and elucidate its underlying mechanisms. Methods: C57BL/6J male mice were randomly assigned into four groups: (1) sedentary low-fat diet (LF-SED), (2) LF diet with free access to a voluntary running wheel (LF-RUN), (3) sedentary high-fat diet (HF-SED; 45% of calories from fat), and (4) HF-RUN. Endothelium-dependent (acetylcholine, ACh-induced) and endothelium-independent (Sodium Nitroprusside, SNP-induced) vasodilation were assessed using isolated, pressurized mesenteric arteries. Protein levels of endothelial nitric oxide synthase (eNOS) related signals (phosphorylated eNOS and Akt), and oxidative stress markers; Protein Kinase B (Akt), NADPH Oxidase (NOX 2 & 4), Superoxide Dismutase (SOD 1 & 2), and Uncoupling protein 2 (UCP2) were quantified via Western blot analysis. Results: ACh-induced vasodilation was significantly reduced in the mesenteric arteries of HF-SED mice compared to LF-SED mice but was preserved in HF-RUN mice. This enhanced ACh-induced vasodilatation in HF-RUN and LF-SED was abolished by pre-incubation of NOS inhibitor NG-nitro-L-arginine-methyl ester (L-NAME) or UCP2 inhibitor, Genipin. A voluntary running normalized HFD-induced reductions in p-eNOS, p-Akt, UCP2, and SOD1/2 levels and suppressed elevated NOX2/4 levels. Conclusion: These findings demonstrate that voluntary physical activity prevents mesenteric endothelial dysfunction in HFD-induced obesity by preserving eNOS activity and reducing oxidative stress. University of Houston CLASS Research Progress Grant This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.