Geraniol improves endothelial function by inhibiting NOX-2 derived oxidative stress in high fat diet fed mice

• Published in: Biochemical and biophysical research communications Vol. 474; no. 1; pp. 182 - 187
• Main Authors: Wang, Xiaoyu, Zhao, Shiqi, Su, Mengqi, Sun, Li, Zhang, Song, Wang, Dingyu, Liu, Zhaorui, Yuan, Yue, Liu, Yang, Li, Yue
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 20.05.2016
• Subjects: 60 APPLIED LIFE SCIENCES; ACETYLCHOLINE; ALCOHOLS; Animals; ARTERIOSCLEROSIS; atherosclerosis; BIOMEDICAL RADIOGRAPHY; blood serum; CELL PROLIFERATION; DIET; Diet, High-Fat - methods; Dietary Fats - metabolism; Dose-Response Relationship, Drug; endothelial cells; Endothelial dysfunction; Endothelium, Vascular - drug effects; Endothelium, Vascular - physiology; FATS; FLUORESCENCE; Geraniol; HEXADECANOIC ACID; high fat diet; image analysis; INFLAMMATION; INJURIES; laboratory animals; Male; Membrane Glycoproteins - metabolism; MICE; Mice, Inbred C57BL; MOLECULES; NADP (coenzyme); NADPH Oxidase 2; NADPH Oxidases - metabolism; neoplasm cells; NEOPLASMS; NITROGEN 20; NOX-2; OXIDASES; OXIDATION; oxidative stress; Oxidative Stress - drug effects; Oxidative Stress - physiology; OXYGEN; palmitic acid; PATIENTS; protein synthesis; reactive oxygen species; Reactive Oxygen Species - metabolism; ROS; TERPENES; Terpenes - administration & dosage; thiobarbituric acid-reactive substances; Treatment Outcome; TUMOR CELLS; vasodilation; Vasodilation - drug effects; Vasodilation - physiology; Western blotting; Endothelial dysfunction; NOX-2; Geraniol; ROS
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2016.04.097

Endothelial dysfunction occurs in obese patients and high-fat diet (HFD) fed experimental animals. While geraniol has been reported to ameliorate inflammation and oxidative stress, inhibit tumor cell proliferation, and improve atherosclerosis, its direct effect on endothelial function remains uncharacterized. The present study therefore investigated the effect of geraniol on endothelial function in HFD mice and its underlying mechanisms. C57 BL/6 mice were fed an HFD (n = 40) or a normal diet (n = 20) for 8 weeks. HFD fed mice then were randomized to intraperitoneal treatment with geraniol (n = 20) or vehicle (n = 20) for another 6 weeks. Acetylcholine (Ach)-induced endothelial dependent vasorelaxation was measured on wire myography; reactive oxygen species (ROS) generation was assessed by fluorescence imaging, and NADPH oxidases (NOXs) and adhesive molecules VCAM-1 and ICAM-1 protein expression by western blotting. Geraniol improved endothelial function in HFD fed mice, as evidenced by its: 1. restoring endothelial dependent vasorelaxation induced by Ach, and reversing increased VCAM-1 and ICAM-1 expression; 2. attenuating HFD induced increased serum TBARS and aortic ROS generation; and 3. downregulating aortic NOX-2 expression in both HFD fed mice and in palmitic acid treated endothelial cells. Geraniol therefore protects against endothelial dysfunction induced by HFD through reducing NOX-2 associated ROS generation. •Geraniol improved endothelial dependent relaxation in high fat diet fed mice.•Geraniol alleviated vascular injury in high fat diet fed mice.•Geraniol inhibited ROS generation through downregulating NOX-2 expression.