[Effects of selenium-enriched garlic on blood lipids and lipid peroxidation in experimental hyperlipidemic rats].

The modulating effects of selenium-enriched garlic on lipid metabolism disorder and lipid peroxidation were studied in hyperlipidemic rats induced by high fat diet. Adult male and female Wistar rats were divided into 6 groups: (A) normal control; (B) high fat diet (HFD) control; (C) HFD + selenite; (D) HFD + selenium-enriched garlic; (E) HFD + common garlic; (F) HFD + common garlic + selenite. The selenium content of diets in groups A, B and E was 0.08 mg/kg diet, while that of the other 3 groups was 2.7 mg/kg diet. At the end of the experimental period (12 weeks), blood and liver were collected for biochemical measurements and for histopathological examination of liver. The results showed that the serum concentrations of TC, TG and LDL-C in groups C, D and F were significantly lower and HDL-C higher than group B. Female rats were more sensitive to HFD exposure than male rats. The peroxidative status of all four experimental groups was significant inhibited as shown by the lower lipid peroxide (MDA) in liver and higher activities of GPX in erythrocytes and liver and SOD in plasma. Selenium contents in liver and kidney of male rats in groups D and F were higher than group C. Significant accumulation of selenium in erythrocytes was observed in groups D and F. The liver of all four experimental groups revealed ameliorated fatty liver induced by HFD. The amelioration of group D was more prominent than other three experimental groups. The results suggested that selenium-enriched garlic is superior to selenite or common garlic in decreasing the blood lipid level and peroxidative status and slightly better than combined common garlic and selenite.

[Study on food safety of genetically modified rice which expressed cowpea trypsin inhibitor by 90 day feeding test on rats].

OBJECTIVE: Rats were fed by transgenic rice which expressed insecticidal protein CPTI (cowpea trypsin inhibitor) to study if the transgenic rice possessed potential toxic or adverse effects. METHODS: Weanling Wistar rats were randomly divided into three groups: T, N and C group. The diet of T group contained 78.3% transgenic rice. The diet of N group contained 74.7% non transgenic rice which was the parent line of the transgenic one. The diet formula of C group was AIN93G. The macro- and micronutrient content were equal in three diets. The rats were fed for 90 days. Food intakes were weight every day, body-weight were weight and body-length were measured every week. In the middle and at the end of feeding period, haematological value and clinical chemistry parameters were measured, at the end of the 90th day, post-mortem organ coefficient were measured, organ tissues analysis was performed and bone density was measured. RESULTS: In most situation, there were no significant differences among the three groups(P > 0.05) and no histopathological damage were detected. At the end of the 1st month, the male rats' body length of the T group was longer than the other two groups and at the end of the test period, the male rats' blood glucose and ALT were lower than the other two groups. In the middle of the test period, the female rats' red blood cell number and hemoglobin were higher than the other two groups and at the end of the test period, the female rats' monocyte number was higher than the other two groups (P < 0.05). But all of the results were in the normal range which had been reported before. CONCLUSION: From the results of the 90 days feeding test of transgenic rice on rats there did not reveal any signs of toxic and adverse effects.

[Studies on comparing the toxicity between sodium selenite and selenomethionine in rats].

OBJECTIVE: To compare the toxicity between sodium selenite and selenomethionine (SeM) and to investigate the indicators of selenium toxicity. METHODS: Weanling Wistar rats of both sexes were randomly divided into seven groups, 14 rats each group. One group was fed basal diet and the others were fed basal diets containing 3, 6, 10 mg greater than that of SeM and female rats were more sensitive to excessive selenium than male rats. Se/kg added as sodium selenite or SeM for 12 weeks. RESULTS: Histopathological changes of the liver were observed in rats on Se 3 mg/kg diets while the decreasing of body weight occurred in rats on 6 Se mg/kg diet. Among the rats fed Se 6, 10 mg/kg diet, the body weight of rats in selenite-treated groups was lower than that of rats in SeM-treated groups. At the 3 or 6 mg/kg Se level, the rats fed SeM suffered slighter hepatic damage than those fed sodium selenite and in male rats slighter than female rats. The abnormal change of ratio of liver weight to body weight was found to be more obvious both in female rats and in selenite-treated rats. GPX activity in liver of female rats reduced with the increase of Se level in diets. However, GPX activity in RBC, plasma, kidneys and liver showed an ascending tendency with the increasing level of dietary Se. CONCLUSION: The minimum dose of intoxication of Se in diet may be around 3 mg/kg. The toxicity of selenite is greater than that of SeM and female rats were more sensitive to excessive selenium than male rats.