Dietary fish oil alters cardiomyocyte Ca2+ dynamics and antioxidant status.
The n-3 polyunsaturated fatty acids (PUFAs) found in fish oil (FO) have been shown to protect against reperfusion arrhythmias, a manifestation of reperfusion injury, which is believed to be induced by the formation of reactive oxygen species (ROS) and intracellular calcium (Ca2+) overload. Adult rats fed a diet supplemented with 10% FO had a higher proportion of myocardial n-3 PUFAs and increased expression of antioxidant enzymes compared with the saturated fat (SF)-supplemented group. Addition of hydrogen peroxide (H2O2) to cardiomyocytes isolated from rats in the SF-supplemented group increased the proportions of cardiomyocytes contracting in an asynchronous manner, increased the rate of Ca2+ influx, and increased the diastolic and systolic [Ca2+]i compared with the FO group. H2O2 exposure increased the membrane fluidity of cardiomyocytes from the FO group. These results demonstrate that dietary FO supplementation is associated with a reduction in the susceptibility of myocytes to ROS-induced injury and this may be related to membrane incorporation of n-3 PUFAs, increased antioxidant defenses, changes in cardiomyocyte membrane fluidity, and the ability to prevent rises in cellular Ca2+ in response to ROS.
Jahangiri
Anisa
A
Department of Physiology, University of Adelaide, Adelaide, SA 5005, Australia. anisa.jahangiri@uky.edu
Leifert
Wayne R
WR
Kind
Karen L
KL
McMurchie
Edward J
EJ
D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D002462:Cell Membrane / Q000737:chemistry / Q000187:drug effects; D019587:Dietary Supplements; D005231:Fatty Acids, Unsaturated / Q000737:chemistry; D005395:Fish Oils / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008297:Male; D032383:Myocytes, Cardiac / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism; D016877:Oxidants / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects* / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction
D000975:Antioxidants; D005231:Fatty Acids, Unsaturated; D005395:Fish Oils; D016877:Oxidants; D006861:Hydrogen Peroxide; D002118:Calcium