Protective effect of omega-3 fatty acids on diethylnitrosamine toxicity in rats.

OBJECTIVES: In this study, it was aimed to investigate the effect of n-3 fatty acids (n-3 FA) on diethylnitrosamine (DEN) toxicity with respect to alterations including nitric oxide (NO) formation, uric acid level as well as some liver related enzymes such as aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) activities in rats. MATERIALS AND METHODS: Forty male Wistar albino rats were used as animal materials. Animals were divided into 4 groups and treated as follows: Rats in group 1 (control) were intraperitoneally (i.p) injected with single dose of saline; rats in group 2 were i.p. injected with DEN at a dose of 150 mg/kg/body weight; rats in group 3 were treated with DEN (via single i.p. injection at 150 mg/kg/body weight) plus n-3 FA (at a dose of 0.4 g /kg/day via subcutaneous route in fish oil) for 7 days, and group 4 received n-3 FA via s.c. route at a dose of 0.4 g/kg/day in fish oil for 7 days. The plasma samples were analyzed for NO, uric acid levels as well as for activities of AST, ALT and ALP. RESULTS: Uric acid level was lower in DEN group than in control. In addition, NO level and AST, ALT, ALP activities in DEN group were significantly higher than in control. Nitric oxide concentration, ALT and ALP activities in DEN + n-3 FA treated rats were lower than in DEN alone. Uric acid level in DEN + n-3 FA group was higher than in DEN group. CONCLUSIONS: These results suggest that n-3 fatty acids could ameliorate the toxic effects of DEN in part by means of its free radical scavenging activity and may be of therapeutic value in the protection of liver against toxic effects of DEN.  

Effects of reduced glutathione on nitric oxide level, total antioxidant and oxidant capacity and adenosine deaminase activity.

The aim of this study was to determine the effect of exogenous GSH, an important antioxidant containing thiol group, on total antioxidant capacity (TAC) and total oxidant capacity (TOC), adenosine deaminase (ADA), a significant indicator of cellular immunity, and nitric oxide (NO) concentrations in rabbits. Sixteen healthy New Zealand rabbits were divided into 2 groups as control and GSH-treated group. Animals in control group received single intraperitoneal (ip) administration of 0.9% saline. Rabbits in GSH-treated group received reduced L-glutathione (10 mg/kg) (ip). Blood samples were taken from the marginal ear vein 0, 3, 6 and 12 hours after injection. Plasma TAC and NO levels were not statistically different between control and GSH group at 0 and 12 hours. Plasma TAC level was found to be significantly higher (p < 0.05) while NO level was found to be significantly lower (p < 0.05) in GSH treated group when compared to control group at 3 and 6 hours. Plasma TOC and ADA activity were not statistically different between control and GSH group during experiment. In conclusion, exogenous GSH resulted in an alteration of TAC and NO but not TOC and ADA, so exogenous GSH may be a valuable enhancer of the antioxidant system.

Acute tamoxifen treatment increases nitric oxide level but not total antioxidant capacity and adenosine deaminase activity in the plasma of rabbits.

Tamoxifen is a synthetic non steroidal anti-estrogen used to treat patients with breast cancer and healthy subjects with high risk of breast cancer. It was aimed to study the short term effects of tamoxifen on the plasma total antioxidant capacity (TAC), nitric oxide (NO) and the adenosine deaminase activity (ADA) in healthy rabbits. Sixteen healthy New Zealand rabbits were allocated to 2 groups including controls and tamoxifen treated animals. Controls received a single application of 0.9% saline via oral route while the treated rabbits received orally tamoxifen (dissolved in 0.9% saline, at a dose of 5 mg/kg). Blood samples were collected at 6 and 24 hours following the treatments. Plasma TAC and ADA were not affected by Tamoxifen treatment. However, NO level in tamoxifen treated group was increased at 24 hours following tamoxifen treatment as compared to controls. In conclusion, acute tamoxifen treatment may not affect the antioxidant status and cellular immunity, as evidenced by unaltered TAC and ADA. However, NO level was increased as early as 24 hours following tamoxifen treatment.

Omega-3 fatty acid application reduces yolk and plasma cholesterol levels in Japanese quails.

The aim of this study was to determine the effects of fish oil, rich in omega-3 fatty acids, on the cholesterol levels in egg yolk and plasma in Japanese quail. Additionally, the effects of these fatty acids on selected biochemical parameters, and yolk and quail weights were investigated. Thirty healthy laying Japanese quails were divided into two groups including control and omega-3 fatty acid treated group. Fish oil capsules were administrated orally to the quails in the omega-3 treated group every other day for 3 weeks. Yolk cholesterol level was found to be significantly lower in the omega-3 treated group compared to the control. Plasma cholesterol levels were lower; plasma calcium levels were higher at 3rd week in omega-3 fatty acid treated group than those in control. On the other hand, plasma phosphorus and glucose levels in omega-3 fatty acid group were significantly lower at 3rd week than those at the beginning of experiment. In conclusion, it was found that orally supplemented omega-3 fatty acid reduced the levels of cholesterol in egg yolk and plasma in quails.

Effects of therapeutic dose of ivermectin on plasma nitric oxide and total antioxidant capacity in rabbits.

BACKGROUND: Ivermectin, an acaricide and anthielmintic drug of the family of avermectins may produce free radicals thus resulting cytotoxic effect on the parasite. Nitric oxide (NO) acts as free radicals and as host defense mechanisms. The antioxidant capacity (TAC) can be described by the analysis of single components in the defense systems against free radicals. It was aimed to study the effects of therapeutic doses of ivermectin on the plasma adenosine deaminase (ADA) and gamma glutamyl transpeptidase activities (GGT), total antioxidant capacity (TAC), nitric oxide (NO) and total protein, albumin, globulin levels in rabbits. MATERIAL AND METHODS: Twenty healthy New Zealand rabbits were allocated to 2 equal groups. Group I received 0.5 mg/kg and Group II received 1 mg/kg of ivermectin via subcutaneous injection. Blood samples were collected before the experiment, at 24 and 120 hours following the treatments. RESULTS: Ivermectin at therapeutic doses increased plasma NO level at 24 h while decreased TAC at 120 h and did not alter other parameters. CONCLUSION: These findings may suggest that ivermectin is a safe antiparasitic drug for mammals but to less extent, it may have an effect on the oxidant/antioxidant balance.