title: Administration of tauroursodeoxycholic acid prevents endothelial dysfunction caused by an oral glucose load.
abstract: Postprandial hyperglycaemia leads to a transient impairment in endothelial function; however, the mechanisms remain largely unknown. Previous work in cell culture models demonstrate that high glucose results in endoplasmic reticulum (ER) stress and, in animal studies, ER stress has been implicated as a cause of endothelial dysfunction. In the present study, we tested the hypothesis that acute oral administration of tauroursodeoxycholic acid (TUDCA, 1500 mg), a chemical chaperone known to alleviate ER stress, would prevent hyperglycaemia-induced endothelial dysfunction. In 12 young healthy subjects (seven men, five women), brachial artery flow-mediated dilation (FMD) was assessed at baseline, and at 60 and 120 min after an oral glucose challenge. Subjects were tested on two separate visits in a single-blind randomized cross-over design: after oral ingestion of TUDCA or placebo capsules. FMD was reduced from baseline during hyperglycaemia under the placebo condition (-32% at 60 min and -28% at 120 min post oral glucose load; P<0.05 from baseline) but not under the TUDCA condition (-4% at 60 min and +0.3% at 120 min post oral glucose load; P>0.05 from baseline). Postprandial plasma glucose and insulin were not altered by TUDCA ingestion. Plasma oxidative stress markers 3-nitrotyrosine and thiobarbituric acid reactive substance (TBARS) remained unaltered throughout the oral glucose challenge in both conditions. These results suggest that hyperglycaemia-induced endothelial dysfunction can be mitigated by oral administration of TUDCA, thus supporting the hypothesis that ER stress may contribute to endothelial dysfunction during postprandial hyperglycaemia.
authors: Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO 65211, U.S.A.
authors: Lauren K
authors: LK
authors: Walsh
authors: Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO 65212, U.S.A.
authors: Robert M
authors: RM
authors: Restaino
authors: Department of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Portland, OR 97239, U.S.A.
authors: Martha
authors: M
authors: Neuringer
authors: Department of Internal Medicine, University of Missouri, Columbia, MO 65212, U.S.A.
authors: Camila
authors: C
authors: Manrique
authors: Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO 65211, U.S.A. Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO 65201, U.S.A. Department of Child Health, University of Missouri, Columbia, MO 65212, U.S.A. padillaja@missouri.edu.
authors: Jaume
authors: J
authors: Padilla
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D002318:Cardiovascular Diseases / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control*; D059865:Endoplasmic Reticulum Stress / Q000187:drug effects; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism; D005260:Female; D006801:Humans; D006943:Hyperglycemia / Q000150:complications* / Q000378:metabolism*; D007328:Insulin / Q000378:metabolism; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects; D019518:Postprandial Period; D013655:Taurochenodeoxycholic Acid / Q000008:administration & dosage*; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D007328:Insulin; D017392:Thiobarbituric Acid Reactive Substances; C002744:3-nitrotyrosine; D014443:Tyrosine; D013655:Taurochenodeoxycholic Acid; C031655:ursodoxicoltaurine
keywords: ER stress; endothelial function; postprandial hyperglycaemia; tauroursodeoxycholic acid (TUDCA)