The influence of different durations of aerobic exercise on fuel utilization, lactate level and antioxidant defense system in trained rats

This study investigated the influence of different durations of aerobic exercise on fuel utilization, lactate levels and antioxidative status in trained rats. Forty rats underwent physical training (T, n = 20) or non- training (NT, n = 20) for 6 weeks. For physical training, animals exercised on a treadmill for 30 min 5 days per week. At the end of week 6, the animals in each group were subdivided into BE, DE-0.5, DE-1 and DE-2, which were sacrificed at the end of week 6 without having performed exercise or after exercise on a treadmill for 0.5h, 1h and 2h, respectively, immediately before being sacrificed. The plasma glucose level in DE-2 of the NT group was significantly lower than in the other groups. Muscle and liver glycogen levels were significantly lower in DE-1 and DE-2, but there were no significant differences between DE-1 and DE-2 in the T group. Liver protein in DE-2 of the NT group was significantly lower. Muscle TG levels were decreased in DE-0.5 of the T group, while those of the NT group were decreased in DE-1. FFA levels were increased in DE-0.5 of the T group and in DE-1 of the NT group. Lactate levels were increased in DE-0.5 of the NT group, while they were increased in DE-1 of the T group. Catalase activity of the T group was lower in BE but higher in DE-0.5, DE-1 and DE-2. SOD activities were higher in trained rats, while the GSH/GSSG ratios were higher in BE, DE-0.5 and DE-1 in the T group, and there was no difference in that of DE-2. There were no differences in MDA levels in BE and DE-0.5, but they were significantly lower in DE-1 and DE-2 of the T group. Overall, the results of this study, suggest that training may improve exercise performance by facilitating the mobilization and oxidation of fat and conserving limited carbohydrate storage, and that it may delay the onset of fatigue and enhance the antioxidative defense system, but cannot support two hours of vigorous exercise.

Effects of Water Extracts of Red Pepper Seeds Powder on Antioxidative Enzyme Activities and Oxidative Damage in Rats Fed High-Fat and High-Cholesterol Diets

The purpose of the present study was to examine the effects of water extracts from red pepper seeds powder on antioxidative enzyme activities and oxidative damage in groups of rrats fed high-fat and high-cholesterol diets group (HFC). The Rrats were divided into the following five experimental groups which are : composed ofa normal diet group, a high fat.high cholesterol diet group, and a high fat.high cholesterol diet group supplemented with different amounts contents (1%, 2% and 4%) of red pepper seeds powder water extracts supplemented groups (HFCW1, HFCW2 and HFCW4, respectively). Body weight gains and food intake were lower ofin the red pepper seed water extracts groups were lower than those inof the HFC group. Hepartic xanthine oxidase (XOD) activity was decreased in the HFCW2 and HFCW4 groups compared to the HFC group. Hepartic glutathione peroxidase (GSH-px) activitiyactivity was increased in the HFCW4 group compared to the HFC group. Hepatic superoxide radicals within the mitochondria and microsomes of cells were significantly reduced in the HFCW2 and HFCW4 groups compared to the HFC group. Hepartic hydrogen peroxide in the cytosol was significantly reduced in the HFCW3 and HFCW4 groups compared to the HFC group. Hepatic carbonyl values in the microsomes and mitochondria were significantly reduced in the HFCW4 group compared to the HFC group. Hepartic thiobarbituric acid reaction substance (TBARS) activity was decreased in the HFCW2 group compared to the HFC group. These results suggest that water extracts of red pepper seeds powder may reduce oxidative damage by activation of antioxidative defense systems in rats fed high fat.high cholesterol diets.

Effects of Mulberry Juice and Cake powders on Blood Glucose and Lipid Lowering and Erythrocytic Antioxidative Enzyme Activities in Streptozotocin -Induced Diabetic Rats

The aim of this study was to investigate the effects of mulberry juice and cake powder on blood glucose and lipid status along with intestinal disaccharidase and erythrocyte antioxidative enzyme system in streptozotocin (STZ )-induced diabetic rats. Sprague-Dawley male rats weighing 100 +/- 10 g were randomly assigned to one normal group, and eight STZ-induced diabetic groups: control diet group without mulberry juice and cake powders (DM-C ), three mulberry juice powder groups (0.5%:DM-0.5J, 1%:DM-1J, 2%:DM-2J )and four mulberry cake powder groups (0.25%:DM-0.25C, 0.5%:DM-0.5C, 1%:DM-1C, 2%:DM-2C ). After three-week feeding of each experimental diet, diabetes was induced by intravenous injection of 50 mg/kg body weight of STZ in sodium citrate buffer (pH 4.3 )via tail vein of eight DM groups. Rats were sacrificed at the 9th day of diabetic states. Level of blood glucose was 505 mg/dl in DM-C group but it was 28% and 39% lower in mulberry juice and cake powder fed groups, respectively, than the DM-C group. Activities of maltase, sucrase and lactase in proximal part of small intestine were significantly lower in the mulberry juice and cake powder groups by 42~47% than those of DM-C group. Erythrocytic superoxide dismutase, glutathione peroxidase and catalase activities were significantly reduced by STZ but increased close to normal levels along with less accumulation of thiobarbituric acid reactive substances (TBARS ). Serum levels of triglyceride and total cholesterol and HDL-cholesterol by STZ-DM were reduced and increased respectively, to the normal levels by the mulberry juice and cake powder. Except the levels of TBARS, the effects on the other measure-ments by the various dietary levels of mulberry juice and cake powder were almost same and the effect of the cake powder was most significant at the lowest level. These results indicate that mulberry juice and cake powders have considerable hypoglycemic effect and strengthening antioxidant defense systems at the low levels in diabetic state and may be able to reduce diabetic complications.

Antioxidant Effects and Improvement of Lipid Metabolism of Mulberry fruit, Mulberry Leaves and Silkworm Powder with Different Mixing Ratios in Streptozotocin-Induced Diabetic Rats

This study was conducted to investigate the effects of mulberry fruit, mulberry leaves and silkworm powder with different mixing ratios on hepatic antioxidative system and lipid metabolism in streptozotocin-induced diabetic rats. Sprague-Dawley male rats weighing 100+/-10 g were induced diabetic by 50 mg/kg bw streptozotocin and randomly assigned to following experimental groups; normal diet group (DM) , 0.3% and 0.6% mulberry fruit diet groups (F and 2F) , 0.3% mulberry leaves diet group (M) , 0.3% silkworm powder diet group (S), 0.15% mulberry fruit + 0.15% mulberry leaves diet group (FM), 0.15% mulberry fruit + 0.15% silkworm powder diet group (FS) , 0.1% mulberry fruit + 0.1% mulberry leaves + 0.1% silkworm powder diet group (FMS) . The experimental diets were fed for 4 weeks. Hepatic SOD activity was not changed significantly by any of single or combined supplementations of mulberry fruit, leaves and silkworm powder but GSH-px and catalase activities were increased by the groups supplemented with two or three of the test ingredients (FM, FS, FMS) as compared with the DM group. Hepatic TBARS value was not reduced significantly by any of the supplementations but lipofuscin contents were significantly reduced in the FM, FS and FMS groups as compared with the DM group. Hepatic mitochondria and microsomal carbonyl values were reduced by the single and combined supplementations of the test ingredients. Hepatic HMG-CoA reductase activities were increased in the all supplementation groups as compared with the DM group. Hepatic total lipid and triglyceride contents were increased but cholesterol contents reduced in the supplemented groups. The effects on the enzyme activities, peroxide or its products and lipid contents were most remarkable in the FMS group. In conclusion, mulberry fruit, mulberry leaves and silkworm powder have the favorable effects on antioxidative system and lipid metabolism in the diabetic liver and the mulberry fruit, leaves and silkworm powder with equal ratio exert the synergistic effect expectedly to prevent diabetic complications.

Effects of Supplementation of Puerariae Radix Ethanol Extract on the Antioxidative Defense System in Rats

This study was performed to investigate the effect of Puerariae radix-ethanol extracts rich in isoflavone on the antioxidative system of rats. For this purpose, first, Puerariae radix was extracted with ethanol, and its total isoflavone and puerarin contents were analysed. Second, female Sprague Dawley rats were fed for 6 weeks with four diets which were based on AIN96G diet and supplemented with Puerariae radix-ethanol extracts to contain isoflavone. The isoflavone contents of four experimental diets were 0 mg, 500 mg, 1,000 mg, 2,000 mg per kg diet, respectively (control, P0.05%, P0.1%, P0.2%). Liver and erythrocyte activities of antioxidative enzyme such as superoxide dismutase (SOD), catalase, glutathione peroxidase (GSHpx) were measured. Also, plasma and liver malondialdehyde (MDA) concentrations, liver glutathione (GSH) and oxidized glutathione (GSSG) concentrations were measured. The total isoflavone content of Puerariae radix-ethanol extract was 3067.6 mg per 100 g extract and the content of puerarin was 2557.4 mg per 100 g extract. The erythrocyte activities of GSH-Px and catalase were higher in group P0.1% and P0.2%. But SOD activity of erythocyte did not show any difference by the Puerariae radix-ethanol extract supplementation in diet. The activity of SOD in liver increased significantly by the supplementation of extract, showing highest level in P0.1% group. The liver GSH concentration increased significantly in group of P0.05%, P0.1%, and P0.2% compared with control group (p < 0.05). The GSSG concentration in liver showed no difference by the supplementation of Puerariae radix extract from the control group, except P0.2% group. The plasma MDA concentration did not show any significant differences by the extract supplementation. But the liver MDA concentration decreased by the extract supplementation, showing the lowest level in P0.1% diet group. These results suggest that the supplementation of Puerariae radix-ethanol extract can inhibit lipid peroxidation in liver and enhance the antioxidative defense competence of rats.

Effect of Seeds Extract of Paeonia Lactiflora on Antioxidative System and Lipid Peroxidation of Liver in Rats Fed High-Cholesterol Diet

This study was conducted to investigate the antioxidative effects of Paeonia lactiflora (PL) seeds on antioxidative defense system and lipid peroxidation of liver in rats fed high-cholesterol diet. Sprague-Dawley male rats weighing 100+/-10g were randomly assigned into five experimental groups fed 0.5% cholesterol ; HC group which was not supplemented PL seeds extract, 0.1% methanol extract diet group (MP1 group), 0.2% methanol extract diet group (MP2 group), 0.05% ether-souble fraction diet group (EP1 group) and 0.1 % ether-souble fraction diet group (EP2 group). Experimental diets were fed ad libitum to the rats for 3 weeks. The activity of hepatic superoxide dismutase (SOD) was not significantly different among all the high cholesterol diet groups. The hepatic glutathione peroxidase (GSHpx) activity in MP2 group was increased to 27% compared to HC group. The activity of hepatic catalase (CAT) was not significantly different among the all high cholesterol diet groups. The hepatic glutathione S-transferase (GST) activity in the EP1 and EP2 groups were increased to 12% and 13%, respectively, as compared to HC group. The levels of hepatic TBARS in the MP1, MP2, EP1 and EP2 groups were reduced by 18%, 21%, 20% and 23%, respectively, as compared with HC group. The contents of lipofuscin in liver was not significantly different among all the experimental groups. The results indicated that PL seeds extract may be reduced oxidative damage by activating antioxidative defense system of hepatic in rats fed high-cholesterol diets.

Effect of Forsythia Viridissima Extracts on Antioxidative System and Lipid Peroxidation of Liver in Rats Fed High-Cholesterol Diet

This study was conducted to investigate the effects of Forsythia viridissima Lindl. (FVL) on antioxidative defense system and lipid peroxidation of liver in rats fed high-cholesterol diet. Sprague-Dawley male rats weighing 100+/-10 g were randomly assigned into five experimental groups fed 0.5% cholesterol ; HC group which was not supplemented FVL extract, 0.05% methanol extract diet group (MSI group), 0.1% methanol extract diet group (MS2 group), 0.025% ethylacetate-souble fraction diet group (ES1 group) and 0.05% ethylacetate-souble fraction diet group (ES2 group). Experimental diets were fed ad libitum to the rats for 3 weeks. The hepatic xanthine oxidase (XOD) activity in the MS2 group was decreased to 20% as compared to HC group. The activities of hepatic superoxide dismutase (SOD) and catalase (CAT) were not significantly different among all the high cholesterol diet groups. The hepatic glutathione peroxidase (GSHpx) activity in MS2, ES2 groups were significantly increased as compared to HC group. The hepatic glutathione S-transferase (GST) activity in the MS2 group was increased to 20% as compared to HC group. The levels of hepatic TBARS in the MS1, MS2, ES1 and ES2 groups were reduced by 13%, 21%, 13% and 21%, respectively, as compared with HC group. The contents of lipofuscin in liver tissue was not significantly different among all the experimental groups. The results indicate that FVL extract may reduce oxidative damage by activating antioxidative defense system of liver in rats fed high-cholesterol diets.