title: Ω3 Supplementation and intermittent hypobaric hypoxia induce cardioprotection enhancing antioxidant mechanisms in adult rats.
abstract: Intermittent hypobaric hypoxia (IH) is linked with oxidative stress, impairing cardiac function. However, early IH also activate cardio-protective mechanisms. Omega 3 fatty acids (Ω3) induce cardioprotection by reducing infarct size and reinforcing antioxidant defenses. The aim of this work was to determine the combined effects of IH and Ω3 on cardiac function; oxidative balance and inflammatory state. Twenty-eight rats were randomly divided into four groups: normobaric normoxia (N); N + Ω3 (0.3 g·kg-1·day-1); IH; and IH + Ω3. IH was induced by 4 intercalate periods of hypoxia (4 days)-normoxia (4 days) in a hypobaric chamber during 32 days. At the end of the exposure, hearts were mounted in a Langendorff system and subjected to 30 min of ischemia followed by 120 min of reperfusion. In addition, we determined HIF-1α and ATP levels, as well as oxidative stress by malondialdehyde and nitrotyrosine quantification. Further, the expression of the antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase was determined. NF-kappaB and myeloperoxidase levels were assessed in the hearts. Relative to N hearts, IH improved left ventricular function (Left ventricular developed pressure: N; 21.8 ± 3.4 vs. IH; 42.8 ± 7.1 mmHg; p < 0.05); reduced oxidative stress (Malondialdehyde: N; 14.4 ± 1.8 vs. IH; 7.3 ± 2.1 μmol/mg prot.; p < 0.05); and increased antioxidant enzymes expression. Supplementation with Ω3 induces similar responses as IH group. Our findings suggest that both, IH and Ω3 in an independent manner, induce functional improvement by antioxidant and anti-inflammatory mechanisms, establishing cardio-protection.
authors: Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile. eherrera@med.uchile.cl.
authors: Emilio A
authors: EA
authors: Herrera
authors: Departamento de Ingeniería Química, Facultad de Ingeniería y Ciencias, Universidad de la Frontera, Temuco 4811230, Chile. Jorge.farias@ufrontera.cl.
authors: Jorge G
authors: JG
authors: Farías
authors: Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile. alejjobq@gmail.com.
authors: Alejandro
authors: A
authors: González-Candia
authors: Departamento de Ingeniería Química, Facultad de Ingeniería y Ciencias, Universidad de la Frontera, Temuco 4811230, Chile. s.short01@ufromail.cl.
authors: Stefania E
authors: SE
authors: Short
authors: Departamento de Nutrición, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile. catalinacarrasco@med.uchile.cl.
authors: Catalina
authors: C
authors: Carrasco-Pozo
authors: Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile. rcastillo@med.uchile.cl.
authors: Rodrigo L
authors: RL
authors: Castillo
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000532:Altitude Sickness / Q000188:drug therapy* / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D002316:Cardiotonic Agents / Q000494:pharmacology*; D019587:Dietary Supplements; D004734:Energy Metabolism / Q000187:drug effects; D015525:Fatty Acids, Omega-3 / Q000627:therapeutic use*; D006321:Heart / Q000187:drug effects; D000860:Hypoxia / Q000150:complications / Q000188:drug therapy*; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism; D066298:In Vitro Techniques; D007249:Inflammation / Q000378:metabolism / Q000517:prevention & control; D008297:Male; D009206:Myocardium / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D016277:Ventricular Function, Left / Q000187:drug effects
chemical_list: D000975:Antioxidants; D002316:Cardiotonic Agents; D015525:Fatty Acids, Omega-3; C497444:Hif1a protein, rat; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D000255:Adenosine Triphosphate