Résumé
Omega-3 long chain polyunsaturated fatty acids [LCPUFA] exhibit cytoprotective and cytotheraputic actions within lens membrane against ischemia, chronic light exposure, oxidative stress, inflammation and aging. This experiment was done to illustrate the effect of alpha linolenic acid [ALA], ecosapentaenoic acid [EPA] and docosahexaenoic acid [DHA] of omega-3 fatty acids in improving or delaying the onset of cataract formation induced by lipid peroxidation. Isolated eye lenses were incubated in media containing oxidized oil with or without omega-3 fatty acids for 48 hrs. The lenses were examined by the binocular microscope to discover any lens opacity that may occur during incubation. The changes in the character of the lens crystallins were investigated by electrophoretic analysis. A marked opacity was observed in the group of lenses incubated in oxidized oil with or without ALA, with an increase in the levels of malondialdehyde [MDA], Na[+] and Ca[+2] while reduced glutathione [GSH], protein-SH, K[+] and lens membrane Na, K-ATPase activity were significantly decreased. No observed lens opacification occurred in rat lenses incubated with DHA and EPA. So, the presence of DHA and EPA in culture media proved to be beneficial, since they could cause retardation of the complications indicated by the above parameters. Our finding suggested that DHA and EPA omega-3 may prevent or improve and delay cataract formation, while ALA omega-3 may lead to lens opacification