title: L-Arginine and vitamin C attenuate pro-atherogenic effects of high-fat diet on biomarkers of endothelial dysfunction in rats.
abstract: High-fat diet (HFD) is known to cause endothelial dysfunction and contribute to atherosclerosis progression. The objective of this study was to evaluate the efficacy of L-arginine (L-Arg) and vitamin C supplementation as a potentially useful strategy for modulation of serum homocysteine (Hcy) levels, tumor necrosis factor alpha (TNF-α), oxidative stress, and insulin resistance induced by HFD in rats. Six weeks-old female and male Wistar rats were divided into five groups of twelve rats each and treated for six weeks with: group 1, standard diet; group 2, HFD; group 3, HFD supplemented with L-Arg (20g/kg diet); group 4, HFD supplemented with L-Arg (20g/kg diet) plus vitamin C (100mg/kg diet); group 5, HFD supplemented with vitamin C (100mg/kg diet). HFD significantly elevated TNF-α, reduced total antioxidant status (TAS), and increased insulin resistance (HOMA-IR). Significant increases of total cholesterol (TCH), LDL cholesterol (LDL), triglyceride (TG) and a decrease of HDL cholesterol (HDL) were observed in HFD rats. Supplementation with l-Arg prevented the decrease of TAS and the increases in HOMA-IR, LDL, and TG levels. Moreover, Hcy and TNF-α levels were reduced in L-Arg supplemented group. Supplementation with vitamin C significantly atenuated TAS decrease and lowered LDL levels. L-Arg plus vitamin C enhanced L-Arg effect on TAS and protected against TNF-α increase. Western blot analysis showed that l-Arg supplementation of HFD rats reduced the level of protein carbonyls. Taken together, these findings indicate that supplemental l-arginine and/or vitamin C, by their abilities to modulate biomarkers of HFD-induced endothelial dysfunction, are anti-atherogenic.
authors.affiliation: Department of Education and Obesity Treatment and Metabolic Disorders, Poznan University of Medical Sciences, Szamarzewskiego 84 Str., 60-569 Poznan, Poland.
authors.forename: Paweł
authors.initials: P
authors.lastname: Bogdański
authors.affiliation: Department of Human Nutrition and Hygiene, Poznan University of Life Sciences, Wojska Polskiego 31 Str., 60-624 Poznan, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Suliburska
authors.affiliation: Department of Education and Obesity Treatment and Metabolic Disorders, Poznan University of Medical Sciences, Szamarzewskiego 84 Str., 60-569 Poznan, Poland.
authors.forename: Monika
authors.initials: M
authors.lastname: Szulińska
authors.affiliation: European Centre for Bioinformatics and Genomics, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Piotrowo 1 Str., 61-138 Poznan, Poland.
authors.forename: Marta
authors.initials: M
authors.lastname: Sikora
authors.affiliation: Department of Pediatric Gastroenterology and Metabolic Diseases, University of Medical Sciences, Szpitalna 27/33 Str., 60-572 Poznan, Poland.
authors.forename: Jarosław
authors.initials: J
authors.lastname: Walkowiak
authors.affiliation: Department of Biochemistry and Biotechnology, University of Life Sciences, Dojazd 11 Str., 60-632 Poznan, Poland; Institute of Bioorganic Chemistry, Noskowskiego 12/14 Str., 61-704 Poznan, Poland; Department of Microbiology, Biochemistry & Molecular Genetics, Rutgers University, New Jersey Medical School, International Center for Public Health, Newark, NJ 07103-3535, USA. Electronic address: jakubows@njms.rutgers.edu.
authors.forename: Hieronim
authors.initials: H
authors.lastname: Jakubowski
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001120:Arginine / Q000008:administration & dosage / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000008:administration & dosage / Q000494:pharmacology*; D050197:Atherosclerosis / Q000517:prevention & control*; D015415:Biomarkers / Q000378:metabolism; D059305:Diet, High-Fat / Q000009:adverse effects; D019587:Dietary Supplements; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000503:physiopathology; D005260:Female; D007333:Insulin Resistance; D008055:Lipids / Q000097:blood; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D008055:Lipids; D001120:Arginine; D001205:Ascorbic Acid
keywords: Homocysteine; Insulin resistance; Oxidative stress; l-Arginine