role of omega-3 Fatty acids on LIPI peroxide induced - lens damage in vitro

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

Association of serum a-lipoic acid and cataract patients

Alpha-lipoic acid [LA] and its reduced form, dihydrolipoic acid, have recently gained considerable attention as powerful antioxidants. LA scavenges hydroxyl radicals, hypochlorous acid, peroxynitrite, and singlet oxygen. It also protects membranes by interacting with vitamin C and glutathione, which may in turn recycle vitamin E. In addition to its antioxidant activities, dihydrolipoate may exert prooxidant actions through reduction of iron. Our study aimed to show if there is a relationship between levels of a-lipoic acid, GSH, total antioxidant [TAO], MDA and ferritin and development of cataract in two groups [senile and diabetic cataract] in comparison to control group. The present study shows that the concentrations of a-lipoic acid, GSH, total antioxidant significantly decrease, while MDA and ferritin concentrations significantly increase in both studied groups. Available data strongly suggest that LA, because of its antioxidant properties, is particularly suited to the prevention and/or treatment of diabetic complications that arise from an overproduction of reactive oxygen and nitrogen species. Therefore, alpha-lipoic acid is an important nutritional supplementation that decreases the development or progression of cataract caused by senility or diabetes

Potential prophylactic role of nitric oxide synthase inhibitors on experimentally induced cataract in rats

Nitric oxide [NO] has been related to numerous eye diseases such as cataract. In the present study, we investigated and compared the prophylactic role of selective and nonselective nitric oxide synthase [NOS] inhibitors on the development of selenite induced cataract in rats. The study comprised seven groups; of which four groups served as controls. Cataract was induced in three groups by a single subcutaneous injection of sodium selenite [4mg/kg] in 13-days old Lewis rats. One group was left untreated. The other two groups were treated with aminoguanidine or L-NAME [N G-nitro-L-arginine methyl ester] in a dose of 60mg/kg/day orally for nine days and treatment started two days before selenite injection. Slit lamp examination was done daily to detect lens opacity. Biochemical analysis of lenses was done seven days after selenite injection and included concentrations of nitrite, glutathione, calcium and soluble proteins, in addition to, Cellogel electrophoresis of soluble lens proteins. Ophthalmologic and biochemical results revealed a noticeable prophylactic role of both drugs on selenite cataract development after seven days of selenite injection. In addition, it was observed that aminoguanidine had a better protective role than L-NAME. It can be concluded that NO had an important role in the development of selenite induced cataract in rats since inhibitors of NOS could prevent the development of selenite cataract