Effect of chromium- picolinat on biochemical and histopathological altrations in rats

Chromium III tris [picolinate] [Cr[pie][3]ps a popular nutritional supplement; however its safety has been questioned, especially with regard to its ability to act as a clastogen. The aim of the preset work was to evaluate the biochemical and moiph01gicd changes in the liver following oral administration of Cr-picolinate and the possible protective effect of ascorbic acid [vitamin C] in rats. Fifty male Sprague Dawly rats were divided into five groups included the control group, the rest four groups treated orally with picolinte [0.8 and 1.5 mg 7100 g b. w] alone or in combination with Vitamin C [0.5 mg 7100 g b. w] for 8 weeks. The results indicated that animals treated with Cr-picolinate alone at the high dose level [1.5 mg/100 g b.w] showed a significant decrease in reduced glutathione [GSH] level and activity of glutathione peroxidase [GPx] in liver homogenate or blood accompanied with a significant increase in serum sFas; 8-hydroxy-2 -deoxyguanosine and malondialdehyde [MDA] levels.The hepatocytes showed some degenerative changes in the form of swollen cells and degenerating nuclei, yet some cells showed regeneration by division of their nuclei The methyl green pyronin [MGP] stain showed less level of DNA in the nuclei, the cells appeared swollen and fused in some areas. It could be concluded that consumption of Cr-picolinate for a long time is contributing to health hazards and induced several hazards to liver. Supplementation with extra amounts of vitamin C may be useful to restrain the chromium-induced biochemical and morphological changes to the liver. It is believed that oxidative stress due to Cr- picolinate is a factor contributing to this health hazards

Selected predictors of apoptosis in retinitis pigmentosa

The genetics of non syndromic retinitis pigmentosa [RP] is complex with numerous gene mutations. An attempt to overcome each individual mutation provides an overwhelming challenge. However targeting apoptosis which represents a final common pathway to photoreceptor cell death may provide a more practical approach. This study focused on some predictors of apoptosis in RP and their potential usefulness for patients' management and relatives' early diagnosis. Forty nine RP patients with thirty controls were evaluated genetically and ophthalmologicaly with assessment of plasma total nitrite and nitrate [as an index for nitric oxide], Plasma sFas as an index of apoptosis and plasma fatty acids levels. Autosomal recessive RP was the most common type of inheritance and the levels of plasma sFas and nitric oxide [NO] were significantly higher in retinitis pigmentosa compared to controls. Retinitis pigmentosa patients had significantly lower percentage of plasma omega3 fatty acids especially docosahexaenoic acid [DHA] relative to controls. sFas, NO, and DHA could differentiate between RP patients and control subjects with 100%, 100%, 97% sensitivity and 90%, 90%, 100% specificity respectively. sFas and nitric oxide levels were higher in cases of autosomal recessive [AR] type followed by X-linked, autosomal dominant, then simplex cases relative to the control group this may explain why AR and X-Linked forms are clinically more severe. In conclusion; diagnosis and treatment of RP could be aided by systemic markers or predictors of retinal degeneration. The consistent decrease in the plasma omega 3 fatty acids especially DHA, and increase sFas and nitric oxide levels may draw the attention upon the use of these markers as laboratory tests for relatives of affected patients who are at high risk for having retinitis pigmentosa. Also, omega 3 fatty acids in the form of DHA were recommended as possible supplements for the patients and their relatives

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

Taurine as anticataractogenic agent in galactose - feeding rats

The present study was designed to investigate the effect of taurine on the onset and maturation of galactose induced cataract. Fort y Male Sprague - Dawley rats [21 days old] were divided into 4 groups containing ten rats each. Group 1 received control diet, group 2 received 30% galactose in the diet, group 3 received the group 2 diet plus 2% taurine solution and group 4 received control diet plus 2% taurine solution. After the period of 28 days, biochemical parameters such as lipid peroxidation products, aldose reductase, superoxide dismutase, catalase, protein thiol and reduced glutathione were estimated in the lens. Crystallin profile was analyzed by column chromatography. Galactose-fed rats showed increased lipid peroxidation and impaired antioxidant status of the lens with an increase in maturation of cataract. Taurine administration to galactose- fed rats attenuated the increased lipid peroxidation, enhanced the levels of antioxidant, inhibited the activity of aldose reductase enzyme and improved the crystallin profile. Inhibitions of peroxidation markers and up regulation of antioxidant activity of rat lens by taurine signify the potential utility of taurine as anticataractogenic agent in diabetic rats

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