Membrane effects of the n-3 fish oil fatty acids, which prevent fatal ventricular arrhythmias.
ABSTRACT Fish oil fatty acids are known to exert beneficial effects on the heart and vascular systems. We have studied the membrane effects on ion channel conductance by the n-3 fish oil fatty acids that account for these beneficial effects. We have confirmed that these fatty acids prevent fatal cardiac arrhythmias in a reliable dog model of sudden cardiac death. This finding was followed by experiments indicating that the n-3 fatty acids electrically stabilize heart cells and do so largely through modulation of the fast voltage-dependent Na(+) currents and the L-type Ca(2+) channels in a manner, which makes the heart cells resistant to arrhythmias. Others and we have demonstrated that these membrane effects on the heart can prevent fatal cardiac arrhythmias in humans.
SourceAvailable from: Elias Gustavo Figueroa[Show abstract] [Hide abstract]
ABSTRACT: Background Intermittent hypobaric hypoxia (IHH) induces changes in the redox status and structure in rat testis. These effects may be present in people at high altitudes, such as athletes and miners. Polyunsaturated fatty acids (PUFA) can be effective in counteracting these oxidative modifications due to their antioxidants properties. The aim of the work was to test whether PUFA supplementation attenuates oxidative damage in testis by reinforcing the antioxidant defense system. The animals were divided into four groups (7 rats per group): normobaric normoxia (~750 tor; pO2 156 mmHg; Nx); Nx¿+¿PUFA, supplemented with PUFA (DHA: EPA¿=¿3:1; 0.3 g kg¿1 of body weight per day); hypoxic hypoxia (~428 tor; pO2 90 mmHg; Hx) and, Hx¿+¿PUFA. The hypoxic groups were exposed in 4 cycles to 96 h of HH followed by 96 h of normobaric normoxia for 32 days. Total antioxidant capacity (FRAP) and lipid peroxidation (malondialdehyde, MDA) in plasma and reduced (GSH)/oxidized glutathione (GSSG) ratio, tissue lipid peroxidation (TBARS) and antioxidant enzymes activity were assessed at the end of the study in testis. Also, SIRTUIN 1 and HIF-1 protein expression in testis were determined.ResultsIHH increased lipid peroxidation in plasma and HIF-1 protein levels in testis. In addition, IHH reduced FRAP levels in plasma, antioxidant enzymes activities and SIRTUIN 1 protein levels in testis. PUFA supplementation attenuated these effects, inducing the increases in FRAP, in the antioxidant enzymes activity and HIF-1 levels.Conclusions These results suggest that the IHH model induces a prooxidant status in plasma and testis. The molecular protective effect of PUFA may involve the induction of an antioxidant mechanism.Journal of Biomedical Science 01/2015; 22(1):8. DOI:10.1186/s12929-015-0112-8 · 2.74 Impact Factor
Dataset: JBS Full ResearchJF