title: Rice bran protein hydrolysates reduce arterial stiffening, vascular remodeling and oxidative stress in rats fed a high-carbohydrate and high-fat diet.
abstract: OBJECTIVE
  Rice bran protein hydrolysates (RBPH) contain highly nutritional proteins and antioxidant compounds which show benefits against metabolic syndrome (MetS). Increased arterial stiffness and the components of MetS have been shown to be associated with an increased risk of cardiovascular disease. This study aimed to investigate whether RBPH could alleviate the metabolic disorders, arterial stiffening, vascular remodeling, and oxidative stress in rats fed a high-carbohydrate and high-fat (HCHF) diet.
  
  
  METHODS
  Male Sprague-Dawley rats were fed either a standard chow and tap water or a HCHF diet and 15 % fructose solution for 16 weeks. HCHF rats were treated orally with RBPH (250 or 500 mg/kg/day) for the final 6 weeks of the experimental period.
  
  
  RESULTS
  Rats fed with HCHF diet had hyperglycemia, insulin resistance, dyslipidemia, hypertension, increased aortic pulse wave velocity, aortic wall hypertrophy and vascular remodeling with increased MMP-2 and MMP-9 expression. RBPH supplementation significantly alleviated these alterations (P < 0.05). Moreover, RBPH reduced the levels of angiotensin-converting enzyme (ACE) and tumor necrosis factor-alpha in plasma. Oxidative stress was also alleviated after RBPH treatment by decreasing plasma malondialdehyde, reducing superoxide production and suppressing p47phoxNADPH oxidase expression in the vascular tissues of HCHF rats. RBPH increased plasma nitrate/nitrite level and up-regulated eNOS expression in the aortas of HCHF-diet-fed rats, indicating that RBPH increased NO production.
  
  
  CONCLUSIONS
  RBPH mitigate the deleterious effects of HCHF through potential mechanisms involving enhanced NO bioavailability, anti-ACE, anti-inflammatory and antioxidant properties. RBPH could be used as dietary supplements to minimize oxidative stress and vascular alterations triggered by MetS.
authors.affiliation: Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.
authors.forename: Ketmanee
authors.initials: K
authors.lastname: Senaphan
authors.affiliation: Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.
authors.forename: Weerapon
authors.initials: W
authors.lastname: Sangartit
authors.affiliation: Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.
authors.forename: Poungrat
authors.initials: P
authors.lastname: Pakdeechote
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.
authors.forename: Veerapol
authors.initials: V
authors.lastname: Kukongviriyapan
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.
authors.forename: Patchareewan
authors.initials: P
authors.lastname: Pannangpetch
authors.affiliation: Department of Food Technology, Faculty of Technology, Khon Kaen University, Khon Kaen, 40002, Thailand.
authors.forename: Supawan
authors.initials: S
authors.lastname: Thawornchinsombut
authors.affiliation: Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, E1 2ES, UK.
authors.forename: Stephen E
authors.initials: SE
authors.lastname: Greenwald
authors.affiliation: Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand. upa_ku@kku.ac.th.
authors.forename: Upa
authors.initials: U
authors.lastname: Kukongviriyapan
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage; D000975:Antioxidants / Q000008:administration & dosage; D059305:Diet, High-Fat / Q000009:adverse effects; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D008297:Male; D024821:Metabolic Syndrome / Q000503:physiopathology / Q000517:prevention & control*; D012275:Oryza; D018384:Oxidative Stress / Q000187:drug effects*; D010940:Plant Proteins / Q000008:administration & dosage* / Q000378:metabolism; D011492:Protein Hydrolysates / Q000008:administration & dosage; D051381:Rats; D017207:Rats, Sprague-Dawley; D012639:Seeds / Q000737:chemistry*; D066253:Vascular Remodeling / Q000187:drug effects*; D059289:Vascular Stiffness / Q000187:drug effects*
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D000893:Anti-Inflammatory Agents; D000975:Antioxidants; D004040:Dietary Carbohydrates; D010940:Plant Proteins; D011492:Protein Hydrolysates
keywords: Arterial stiffness; High-carbohydrate and high-fat diet; Metabolic syndrome; Oxidative stress; Rice bran protein hydrolysates; Vascular remodeling