Estimation of the novel antipyretic, anti-inflammatory, antinociceptive and antihyperlipidemic effects of silymarin in Albino rats and mice

Objective: To evaluate the other pharmacological actions of silymarin in Albino rats and mice such as antipyretic, anti-inflammatory, antinociceptive and antihyperlipidemic effects. Methods: Rats were injected intramuscularly with pyrogenic dose of brewer's yeast for the antipyretic test of silymarin. Another group of rats injected with 0.1 mL of 1% carrageenan solution in saline at the subplanter area of the right hind paw for the anti-inflammatory test of silymarin. Another group of mice tested by hot plate method for determination of antinociceptive effect of silymarin. Hyperlipidemia was induced using high fat diet for 2 months to estimate the antihyperlipidemic activity of silymarin. Results: Silymarin showed a significant antipyretic effect of both doses(50 and 100 mg/kg) compared with control untreated group. Moreover, silymarin elucidated a significant anti-inflammatory effect of both doses reflected on the decrease of the rat paw edema every hour interval for 4 h after administration in comparison with control positive group. By the same taken, both doses of silymarine revealed a significant antinociceptive action in hot plate method at 30 and 60 min post administration. Besides, it lowered significantly the serum levels of prostaglandin E2, tumor necrosis factor alpha and interleukin 1 beta after 2 h of silymarin administration in carrageenan induced rat paw edema besides the significant decrease of total cholesterol, triglycerides, low density lipoprotein and significantly elevated high density lipoprotein after 2 weeks of silymarin administration. Conclusions: These outcomes delivered a new vision into the possible pharmacological mechanisms by which silymarin advances antipyretic, anti-inflammatory, antinociceptive and antihyperlipidemic effects.

Role of zinc as an antioxidant and anti-inflammatory to relieve cadmium oxidative stress induced testicular damage in rats

Objective:To investigate the role of zinc in reducing the deleterious effects of cadmium on male gonads.Methods:Rats were injected subcutaneously with CdCl_2 and ZnCl_2 at dose level of2.2 mg/kg(1/40 of LD50 of cadmium per day).Results:The rats treated with cadmium exhibited a significant increase in levels of testicular malondialdehyde,tumor necrosis factor-alpha,nitrogen oxide and inducible nitrogen oxide synthase immunostaining reaction,as well as an elevation of blood hydroperoxide and follicle stimulating hormone.In addition,a significant decrease in testicular ascorbic acid,zinc,reduced glutathione,catalase,superoxide dismutase,sex organ weight,plasma testosterone and luteinizing hormone were observed in the cadmium group.Sperm motility and count were decreased with cadmium treatment,while sperm abnormalities elevated significantly.Zinc treatment was found to mitigate the toxic effects of cadmium on oxidative stress,spermatogenesis,sex hormones,and inflammatory markers.Rats injected with cadmium showed intense histopathological changes.Zinc manifested protective role and markedly reduced tissues damage induced by cadmium.Conclusions:The protective effect of zinc can be attributed to its antioxidant and antiinflammatory properties.