• Journal of Life Science
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• v.18 no.11
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• pp.1584-1591
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• 2008

The effect of Chlorella hot water extract (CE) on hyperglycemia in streptozotocin- induced diabetic rats has not been studied. Therefore, hypoglycemic effect of CE in type I streptozotocin- induced diabetic rats was studied. Rats were fed a semisynthetic diet supplemented with either 3% (the STZ+CE3) and 6% (the STZ+CE6) CE or no supplement the Normal and the STZ-Control rats for 4 weeks. The concentrations of fasting and non-fasting blood glucose were higher in the STZ-Control rats than in the Normal rats, but this rise was lowered in the STZ+CE3 and the STZ+CE6 rats. Serum insulin concentrations were decreased with STZ injection, however, the decreased levels were almost restored to the Normal level with CE supplementation. The increased serum fructosamine levels associated with hyperglycemia were decreased with the CE treatment. The morphology of pancreatic islets in the Normal rat was round and maintained a typical arrangement. The STZ-Control pancreatic beta-cells were found to have significant swelling and severely morphological damaged, however, pancreatic tissue damage by STZ in the CE-supplemented diet group was ameliorated. This study shows that Chlorella hot water extract had a hypoglycemic effect on the STZ-diabetic rats via either increased insulin secretion during recovery or the prevention of STZ-induced pancreatic damage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1310-1317
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• 2003

Effects of dietary cholesterol and/or taurine supplementation on plasma and hepatic lipid peroxidation status and antioxidant enzyme activities were evaluated in rats fed one of the following semisynthetic diets for 5 weeks: control diet (CD, cholesterol-free and taurine-free diet); high cholesterol diet (HCD, CD+1.5% cholesterol): high taurine diet (HTD, CD+1.5% taurine): high cholesterol and high taurine diet (HCHTD, HCD + 1.5% taurine). Plasma malondialdehyde (MDA) level was not influenced by dietary cholesterol or taurine supplementation, while hepatic MDA level was 70% higher in rats fed HCD compared to the value for CD rats (p<0.05). Our observation that taurine supplementation significantly decreased the hepatic MDA level of rats fed HCD, but failed to decrease lipid peroxidation of rats fed CD indicates that the protective effect of taurine in the liver against lipid peroxidation is manifested only under the hypercholesterolemic environment. Plasma and hepatic glutathione peroxidase (GSH-Px) activities were not affected by dietary supplementation of cholesterol or taurine. However, hepatic superoxide dismutase (SOD) activity was significantly reduced by dietary taurine supplementation (p <0.05), and thus significantly lower in rats fed HTD compared to the value for CD (p<0.05). Plasma total cholesterol concentration was positively correlated with hepatic cholesterol concentration as expected (r=0.712, p<0.001). Plasma (r=0.399, p<0.05) and hepatic cholesterol levels (r=0.429, p<0.05) showed a significantly positive correlation with hepatic MDA concentration, respectively. Plasma taurine concentration was negatively correlated with hepatic SOD activity (r=-0.481, p<0.01), and tended to be negatively correlated with hepatic GSH-Px activity without showing statistical significance (r=-0.188, p<0.05). These results indicate an antioxidative effect of taurine in rats with elevated level of lipid Peroxidation due to high intake of dietary cholesterol. Future application of taurine as a safe candidate for a hypolipidemic agent without adversely affecting body's antioxidant defense system is speculated.