• Preventive Nutrition and Food Science
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• v.7 no.3
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• pp.238-244
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• 2002

Protective effect of skin by antioxidative dietary buchu (Chinese chives, Allium tuberosum Router), was evaluated in ICR mice fed diets containing 2% or 5% buchu for 12 months. Lipid peroxidation and protein oxidation in skin, with or without ultraviolet B (UVB) irradiation, activities of antioxidative enzymes, total glutathione concentrations, and non-soluble collagen contents were measured. Dietary buchu decreased significantly in TBARS and protein carbonyl levels in skin compared to the control group, and were lower in those fed 5% than 2% buchu diet group. ICR mice exhibited an age-dependent decrease in antioxidative enzyme activities and total glutathione concentrations on the control diet, but in the groups fed buchu diet the enzyme activities and glu-tathione concentrations remained at youthful levels for most of the study. SOD, glutathione peroxidase, and catalase activities as well as total glutathione concentrations increased with time in the skins of the mice fed buchu diets. Lipid peroxidation and protein oxidation provoked by UVB irradiation on ICR mice skin homogenates were also significantly inhibited by dietary buchu. The buchu diets also decreased the formation of non-soluble collagen in mice skin, compared to the control group. These results suggest that antioxidative components and sulfur-compounds in buchu may confer protective effect against oxidative stress resulting from aging and exposure to ultraviolet irradiation.

• Journal of Nutrition and Health
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• v.44 no.6
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• pp.488-497
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• 2011

Oxygen is necessary to sustain life, yet cellular oxygen metabolism creates destructive elements called free radicals. Free radicals are chemically unbalanced and carrying free electrons that can damage molecules, potentially damaging the cell itself. For this reason, many antioxidant products, including supplements and functional foods, are being developed. In particular, natural products are rich sources of pharmacologically active compounds. The purpose of this study was to investigate the antioxidant effects of target biomaterials in Korean traditional spices such as diallyl sulfide (DAS), capsaicin (CAP), and gingerol (GGR), and to investigate the response of the antioxidant defense system to oxidative stress by hydrogen peroxide ($H_2O_2$) compared to sulforaphane (SFN) in HepG2 cells. After the analysis of the cell viability using Cell Counting kit-8 (CCK-8) assay, we determined that the optimum levels were $200{\mu}M$ DAS, $25{\mu}M$ CAP, $50{\mu}M$ GGR, and $12.5{\mu}M$ SFN. Antioxidant enzymes were measured and protein expression was detected by Western blotting. All treatments showed a significant decrease in antioxidant enzyme activity such as superoxide dismutase, catalse, and glutathione peroxidase in HepG2 cells. Additionally, DAS, CAP, GGR and SFN increased the antioxidant system-related transcription factor Nrf2 which was found to be regulated by the activation of MAPK-JNK in this study. In conclusion, these results indicate the protective effects of DAS CAP, GGR, and SFN against $H_2O_2$-induced oxidative stress.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.11
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• pp.1527-1534
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• 2010

Trace minerals such as zinc, copper, and manganese are essential cofactors for hundreds of cellular enzymes and transcription factors in all animal species, and thus participate in a wide variety of biochemical processes. Immune development and response, tissue and bone development and integrity, protection against oxidative stress, and cellular growth and division are just a few examples. Deficiencies in trace minerals can lead to deficits in any of these processes, as well as reductions in growth performance. As such, most animal diets are supplemented with inorganic and/or organic forms of trace minerals. Inorganic trace minerals (ITM) such as sulfates and oxides form the bulk of trace mineral supplementation, but these forms of minerals are well known to be prone to dietary antagonisms. Feeding high-quality chelated trace minerals or other classes of organic trace minerals (OTM) can provide the animal with more bioavailable forms of the minerals. Interestingly, many, if not most, published experiments show little or no difference in the bioavailability of OTMs versus ITMs. In some cases, it appears that there truly is no difference. However, real differences in bioavailability can be masked if source comparisons are not made on the linear portion of the dose-response curve. When highly bioavailable chelated minerals are fed, they will better supply the biochemical systems of the cells of the animal, leading to a wide variety of benefits in both poultry and swine. Indeed, the use of certain chelated trace minerals has been shown to enhance mineral uptake, and improve the immune response, oxidative stress management, and tissue and bone development and strength. Furthermore, the higher bioavailability of these trace minerals allows the producer to achieve similar or improved performance, at reduced levels of trace mineral inclusion.

• Nutrition Research and Practice
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• v.4 no.2
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• pp.114-120
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• 2010

The effects of grape seeds extract and grape peels extract prepared from grape pomace on the activity of antioxidant enzymes, degree of lipid peroxidation in serum and liver tissue were investigated in rabbits fed on high cholesterol diet. New Zealand white rabbits were divided as follows ; 1) NOR (normal group); 2) CHOL (cholesterol group); 3) GSH (cholesterol + grape seed extract group); 4) GPE (cholesterol + grape peel extract); 5) GSP (cholesterol + grape seed powder); 6) GPP (cholesterol + grape peel powder); 7) GE (cholesterol + grape seed and peel extract); 8) GP (cholesterol + grape seed and peel powder). Eight groups of rabbits were studied for 8 weeks. At the end of the experimental period, rabbits were sacrificed and the liver tissue were removed. Then, GSH, GPx, GST, CAT and MDA in the liver were measured. In liver tissues, total glutathione contents (GSH), glutathione peroxidase (GPx) and catalase (CAT) activity, which was significantly higher by grape seed extract supplementation. The level of malondialdehyde (MDA) was lower in the serum of rabbits fed grape seed extract or grape peel powder plus cholesterol than in the serum of rabbits fed cholesterol alone. It is therefore likely that grape seed extract prepared from grape pomace functioned as antioxidants in vivo, negating the effects of the oxidative stress induced by 1% cholesterol diet. The grape seed extract was found effective in converting the oxidized glutathione into reduced glutathione, and in removing $H_2O_2$ that is created by oxidative stress. The grape peel powder was found to have small influence on reduced glutathione content, CAT and GPX activity, but it increased GST activity in liver tissues, resulting in promoting the combination of lipid peroxide and glutathione (GSH), and further, lowering the formation of lipid peroxide in the serum. Therefore, grape pomace (grape seed extract and grape peel powder) supplementation is considered to activate the antioxidant enzyme system and prevent damage with hypercholesterolemia.

• Nutrition Research and Practice
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• v.11 no.3
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• pp.206-213
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• 2017

BACKGROUN/OBJECTIVES: Although studies have revealed that black garlic is a potent antioxidant, its antioxidant mechanism remains unclear. The objective of this study was to determine black garlic's antioxidant activities and possible antioxidant mechanisms related to nuclear factor erythroid 2-like factor 2 (Nrf2)-Keap1 complex. METHODS/MATERIALS: After four weeks of feeding rats with a normal fat diet (NF), a high-fat diet (HF), a high-fat diet with 0.5% black garlic extract (HF+BGE 0.5), a high-fat diet with 1.0% black garlic extract (HF+BGE 1.0), or a high-fat diet with 1.5% black garlic extract (HF+BGE 1.5), plasma concentrations of glucose, insulin,homeostatic model assessment of insulin resistance (HOMA-IR) were determined. As oxidative stress indices, plasma concentrations of thiobarbituric acid reactive substances (TBARS) and 8-isoprostaglandin $F2{\alpha}$ (8-iso-PGF) were determined. To measure antioxidant capacities, plasma total antioxidant capacity (TAC) and activities of antioxidant enzymes in plasma and liver were determined. The mRNA expression levels of antioxidant related proteins such as Nrf2, NAD(P)H: quinone-oxidoreductase-1 (NQO1), heme oxygenase-1 (HO-1), glutathione reductase (GR), and glutathione S-transferase alpha 2 (GSTA2) were examined. RESULTS: Plasma glucose level, plasma insulin level, and HOMA-IR in black garlic supplemented groups were significantly (P < 0.05) lower than those in the HF group without dose-dependent effect. Plasma TBARS concentration and TAC in the HF+BGE 1.5 group were significantly decreased compared to those of the HF group. The activities of catalase and glutathione peroxidase were significantly (P < 0.05) increased in the HF+BGE 1.0 and HF+BGE 1.5 groups compared to those of the HF group. The mRNA expression levels of hepatic Nrf2, NQO1, HO-1, and GSTA2 were significantly (P < 0.05) increased in the HF with BGE groups compared to those in the HF group. CONCLUSIONS: The improvements of blood glucose homeostasis and antioxidant systems in rats fed with black garlic extract were related to mRNA expression levels of Nrf2 related genes.

• The Journal of Korean Medicine
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• v.28 no.3 s.71
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• pp.57-69
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• 2007

Objectives : Diabetes is a disease in which the body does not produce or properly use insulin. Etiological studies of diabetes and its complications have shown that oxidative stress might play a major role. Therefore, many methods have been tried to regulate free oxygen radicals for treating diabetes and its complications. Ojung-hwan, composed of five crude herbs, has been considered effective for treating symptoms of aging. In male ob/ob mouse of severe obesity, hyperinsulinemia and hyperlipidemia, which are features of NIDDM, the hyperglycemic activities and mechanisms of Ojung-hwan were examined. Methods : Mice were grouped and treated for 5 weeks as follows. Both the lean (C57/BL6J black mice) and diabetic (ob/ob mice) control groups received standard chow. The experimental groups were fed a diet of chow supplemented with 30 and 90 mg Ojung-hwan per 1 kg of body weight for 14 days. The effects of Ojung-hwan extract on the ob/ob mice were observed by measuring the serum levels of glucose, insulin, lipid components, and the kidney levels of superoxide anion radical (${\cdot}\;O{_2}{^-}$), MDA+HAE, GSH/GSSG ratio, and also the enzyme activities involved in polyol pathway. Results : Ojung-hwan lowered the levels of serum glucose and insulin in a dose-dependent manner. Total cholesterol, triglyceride and free fatty acid levels decreased, while the HDL-cholesterol level increased, in Ojung-hwan treated groups. Renal aldose reductase and sorbitol dehydrogenase activities increased in the ob/ob mice, whereas they were inhibited in the Ojung-hwan treated groups. Ojung-hwan inhibited the generation of ${\cdot}\;O{_2}{^-}$ in the kidney. Finally, MDA+HAE levels increased and GSH/GSSG ratio decreased in the ob/ob mice, whereas they improved in the Ojung-hwan treated groups. Conclusions : Ojung-hwan showed antidiabetic and antihyperlipidemic activities by regulating theactivities of polyol pathway enzymes, scavenging reactive oxygen species and reducing the MDA+HAE levels in the ob/ob mice.

• Journal of Nutrition and Health
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• v.35 no.1
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• pp.24-29
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• 2002

Present study investigates the protective effects of green tea against acute ethanol administration on lipid peroxidation and antioxidant system in various regions of rat brain ; cortex, cerebellum, striatum and hippofampus. The following parameters were examined : malondialdehyde(MDA) concentrations and activities of superoxide dismutase(SOD), catalase and glutathione peroxidase(GSH-Px). Male Sprague-Dawley rats of 9 month old were given control diets or those containing 1% green tea powder for 4 weeks, and at tole end of feeding each diet group was received acute ethanol(5g/kg body weight) or equicaloric sucrose solution administration. Results indicated that green tea powder significantly decreased malondialdehyde(MDA) levels in the striatum(81.85nmol/g tissue) and hippocampus(71.68nmol/g tissue), compared to control group(145.68nmol/g tissue in the striatum, 119.04nmol/g tissue in the hippocampus). Also, a significant decrease was observed in the striatum of green tea-ethanol treated group compared to control group. Green tea significantly blocked an ethanol-induced catalase activation in the hippocampus, which means an ethanol administration drew a significant increase only in control diet groups. In conclusion, these results suggest that moderate consumption of green tea leaves ctrl have protective effects against ethanol induced oxidative stress on various regions of rat brain, by significantly reducing MDA concentrations in the striatum and hippocampus and inhibiting ethanol induced catalase activation in the hippocampus.

• Journal of Nutrition and Health
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• v.36 no.7
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• pp.675-683
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• 2003

This study investigated the effect of dietary $\beta$-carotene supplementation on lipid peroxidation and anti oxidative enzyme activity as indices of oxidative stress in diabetic rats. Fifty Sprague-Dawley male rats aging 7 weeks were used as experimental animals, which were divided into the non-diabetic control group and the diabetic group. The diabetic group received an intraperitoneal injection with streptozotocin to induce diabetes. Then the diabetic rats were divided into four dietary groups which contained different amounts of $\beta$-carotene; 0%, 0.002%, 0.02%, or 0.2% of the diet. The diabetic rats were fed the experimental diets and the non-diabetic rats were fed the basal diet without $\beta$-carotene supplementation for 2 weeks and then sacrificed. The diabetic group had a significantly higher blood glucose level than the non-diabetic group. However, blood glucose level were not significantly changed by the level of dietary $\beta$-carotene supplementation. Compared to the non-diabetic control group, the diabetic control group indicated a significant increase of plasma thiobarbituric acid reactive substance (TBARS). Liver TBARS level also tended to be higher in diabetic control group, although it was not significant. The $\beta$-carotene supplementation did not reduce plasma TBARS level. However, Liver TBARS level was significantly decreased when 0.02% or more $\beta$-carotene was supplemented in the diet. The liver lipofuscin level in the diabetic control group was higher than in the non-diabetic control group, but the effect of $\beta$-carotene supplementation did not show any differences. Superoxide dismutase activity was significantly lower in the diabetic group, but it was increased in groups receiving 0.02% or more $\beta$-carotene. Compared to the non-diabetic control group, lower activities of catalase and glutathione peroxidase were observed in the diabetic control group, although it was not significant. Catalase and glutathione peroxidase activities tended to increase as the levels of $\beta$-carotene supplementation increased, although it was not statistically significant. Therefore, it seems that dietary $\beta$-carotene supplementation might reduce diabetic complications by partly decreasing the lipid peroxidation and increasing the activity of antioxidative enzyme in diabetes.

• Nutrition Research and Practice
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• v.8 no.2
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• pp.220-226
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• 2014

BACKGROUND/OBJECTIVES: Arsenic, which causes human carcinogenicity, is ubiquitous in the environment. This study was designed to evaluate modulation of arsenic induced cancer by resveratrol, a phytoalexin found in vegetal dietary sources that has antioxidant and chemopreventive properties, in arsenic trioxide ($As_2O_3$)-induced Male Wistar rats. MATERIALS/METHODS: Adult rats received 3 mg/kg $As_2O_3$ (intravenous injection, iv.) on alternate days for 4 days. Resveratrol (8 mg/kg) was administered (iv.) 1 h before $As_2O_3$ treatment. The plasma and homogenization enzymes associated with oxidative stress of rat kidneys were measured, the kidneys were examined histologically and trace element contents were assessed. RESULTS: Rats treated with $As_2O_3$ had significantly higher oxidative stress and kidney arsenic accumulation; however, pretreatment with resveratrol reversed these changes. In addition, prior to treatment with resveratrol resulted in lower blood urea nitrogen, creatinine and insignificant renal tubular epithelial cell necrosis. Furthermore, the presence of resveratrol preserved the selenium content ($0.805{\pm}0.059{\mu}g/g$) of kidneys in rats treated with $As_2O_3$. However, resveratrol had no effect on zinc level in the kidney relative to $As_2O_3$-treated groups. CONCLUSIONS: Our data show that supplementation with resveratrol alleviated nephrotoxicity by improving antioxidant capacity and arsenic efflux. These findings suggest that resveratrol has the potential to protect against kidney damage in populations exposed to arsenic.

• Korean journal of food and cookery science
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• v.30 no.4
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• pp.369-377
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• 2014

Obesity increases oxidative stress, which could contribute to the development of insulin resistance and hyperglycemia. The purpose of this study was to investigate the hypoglycemic and antioxidant effect of sanchae-namul (SN) in mice with diet-induced obesity. Five-week-old male C57BL/6J mice were fed a basal or high-fat and high-sucrose (HFHS) diet with or without 3% freeze-dried SN powder composed of chamnamul, daraesoon, miyeokchwi, bangpung namul, and samnamul for 12 weeks after a 1-week adaptation. After sacrifice, serum glucose and insulin were measured and the homeostasis model assessment for insulin resistance (HOMA-IR) was determined as well. Hepatic lipid peroxidation, glutathione (GSH), and activities of the antioxidant enzymes were determined. SN given at 3% of the total diet did not significantly influence body weight and food intake in mice fed the HFHS diet. Serum glucose and insulin levels, as well as HOMA-IR values, were significantly lower in the SN group than those in the HFHS group. Thiobarbituric acid reactive substances (TBARS) levels in the liver were decreased significantly in the SN group compared with those in the HFHS group. SN significantly increased the GSH levels and the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in the liver compared with those in the HFHS group. Overall, these findings suggest that SN may be useful in alleviating insulin resistance and hyperglycemia in mice fed HFHS diet; further, the improvement of insulin resistance could partly occur by reducing the oxidative stress.