Aged male and female spontaneously hypertensive rats benefit from n-3 polyunsaturated fatty acids supplementation.
Hypertension-induced myocardial metabolic, structural and electrophysiological remodeling deteriorates with aging and contributes to both heart failure and occurrence of malignant arrhythmias. It has been shown in clinical trials that n-3 polyunsaturated fatty acids (n-3 PUFA) reduce the incidence of cardiovascular diseases and sudden cardiac death. We investigated the cardioprotective effects of n-3 PUFA in aged spontaneously hypertensive rats (SHR) and possible cellular mechanisms involved. Male and female 14-moth-old SHR were fed with n-3 PUFA (Vesteralens, Norway, 20 mg/day for two months) and compared with untreated SHR. Results showed that n-3 PUFA supplementation led to 1) significant decline of blood pressure; 2) suppression of inducible ventricular fibrillation (VF) by 57 % (male) and 67 % (female), although the arrhythmogenic substrates, like fibrosis, hypertrophy and abnormal gap junctions distribution were not eliminated; 3) preservation of the cardiomyocytes and the integrity of their junctions; 4) enhancement of energetic metabolism enzyme activity; 5) augmentation of capillary density associated with increased alkaline phosphatase and decreased dipeptidyl peptidase-4 (DPP4) activity and 6/ increase in gap junction channel connexin-43 expression. Thus, aged male as well as female SHR benefit from n-3 PUFA supplementation that results in decrease in VF susceptibility, partly due to an improvement of myocardial metabolic state, cardiomyocyte and cell-to-cell junctions integrity and Cx43 up-regulation.
Mitašíková
M
M
Institute for Heart Research, Slovak Academy of Sciences, Bratislava, Slovak Republic.
Šmidová
S
S
Macsaliová
A
A
Knezl
V
V
Dlugošová
K
K
Okruhlicová
L
L
Weismann
P
P
Tribulová
N
N
D000367:Age Factors; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002196:Capillaries / Q000187:drug effects; D018031:Connexin 43 / Q000378:metabolism; D019587:Dietary Supplements; D004195:Disease Models, Animal; D004734:Energy Metabolism / Q000187:drug effects; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology*; D005260:Female; D006973:Hypertension / Q000150:complications / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D009206:Myocardium / Q000201:enzymology / Q000378:metabolism* / Q000473:pathology; D032383:Myocytes, Cardiac / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D011918:Rats, Inbred SHR; D019108:Tight Junctions / Q000187:drug effects / Q000378:metabolism; D014693:Ventricular Fibrillation / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology / Q000517:prevention & control*
D018031:Connexin 43; D015525:Fatty Acids, Omega-3