Reactive oxygen species (ROS) are produced by oxidative stresses which cause various chronic diseases such as diabetes and obesity. Ginseng (Panax ginseng C.A. Mayer) has been reported to contain various biological activities such as anti-cancer, anti-diabetic, neuroprotective, radioprotective, anti-amnestic and anti-aging effects. In this study, we investigated the effects of Panax ginseng, treated with high temperatures and high pressures, on oxidative stress in C2C12 myoblasts and 3T3-L1 adipocytes. Oxidative stress was induced in the C2C12 cells through the introduction of H₂O₂ (1 mM), and cells were then treated with various ginseng preparations: dried white ginseng (DG), steamed ginseng (SG) and high temperature and high pressure treated ginseng (HG). In addition, 3T3-L1 preadipocytes were treated with various ginsengs for up to 8 days following standard induction of differentiation. Our results show that HG treatment significantly protected oxidative stress in both cell lines and enhanced gene expression of antioxidant enzymes. Therefore, in this study, we investigated the protective effects of ginseng on the oxidative stress of adipocytes and muscle cells.

Anti-neurodegenerative activities of aqueous extract from propolis were investigated. The aqueous extracts showed strong antioxidant activities in malondialdehyde (MDA) assay, and it effectively inhibited lipid peroxidation. In addition, the aqueous extract presented protective effects against H2O2-induced neurotoxicity in a dose-dependent manner. Our study verified that the aqueous extract has strong antioxidant activity and neuronal cell protective effect which is correlated with its total phenolics (290.75 mg GAE/g) including p-coumaric acid, vanillic acid and gallic acid. These phenolics of propolis may reduce the risk of neurodegenerative disorders, and can be utilized as effective and safe resources of functional food.

The objective of the present study was to evaluate the potential antidiabetic and antioxidant effect of the ethanol extract from Chrysanthemum cornarium L. var. spatiosum(CSE) against alloxan-induced oxidative stress in pancreatic β-cells, HIT-T15. In this study, the antidiabetic effect of CSE was examined using the 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazoliu bromide(MTT) cell proliferation assay, lactate dehydrogenase(LDH) release assay, NAD+/NADH ratio and insulin secretion. To further investigate whether CSE is involved in the antioxidant activity of alloxan-damaged HIT-T15 cells, its antioxidant effect against alloxan-induced oxidative stress was measured in HIT-T15 cells by determining the levels of antioxidant enzymes including superoxide dismutase(SOD), glutathione S-transferase(GST), glutathione reductase(GR) and glutathione peroxidase(GPx). The results of this analysis showed that alloxan significantly decreased cell viability, increased LDH leakage, and lowered NAD+/NADH ratio and insulin secretion in HIT-T15 cells. However, CSE significantly increased the viability of alloxan-treated cells and lowered LDH leakage. The intracellular NAD+/NADH ratio and insulin secretion were also significantly increased by 1.7-fold and 1.3-fold, respectively, after treatment with 100 ㎍/㎖ CSE. The HIT-T15 cells treated with alloxan showed significant decreases in the activities of antioxidant enzymes, while CSE significantly elevated the levels of antioxidant enzymes. These findings suggest that CSE could have a protective effect against cytotoxicity and dysfunction of pancreatic cells in the presence of alloxan-induced oxidative stress.

This study was undertaken to evaluate the relationship between in vitro maturation and plasminogen activators (PAs) activity on porcine cumulus-oocytes complexes (COCs) exposed to oxidative stress. When COCs were cultured in maturation medium with hydrogen peroxide (H2O2), the proportion of the germinal vesicle breakdown (GVBD) and oocytes maturation were decreased with addition of H2O2, and were significantly (p<0.05) lower in medium with 0.1 mM H2O2 than control group. Also, the rate of degenerated oocytes was increased in as H2O2 concentration increased. When COCs were cultured for 48 h, three plasminogen-dependent lytic bands were observed: tissue-type PA (tPA); urokinase-type PA (uPA); and tPA-PA inhibitor (tPA-PAI). PA activity was quantified using SDS-PAGE and zymography. When H2O2 concentration was increased, tPA and tPA-PAI activities also increased in porcine oocytes cultured for 48 h, but not uPA. In other experiment, embryos were divided into three groups and cultured in (1) control medium, (2) control medium with 1.0 mM H2O2 and (3) control medium with 1.0 mM H2O2 along with catalase in concentrations of 0.01, 0.1, and 1.0 mg/ml, respectively. H2O2 decreased the rate of GVBD and maturation in porcine COCs but catalase revealed protective activity against oxidative stress caused by H2O2. In this experiment, tPA and tPA-PAI activities were higher in media with 1.0 mM H2O2 alone. Increasing concentration of catalase decreased tPA and tPA-PAI activities in porcine oocytes. These results indicate that the exposure of porcine follicular oocytes to ROS inhibits oocytes maturation to metaphase-II stage and increase the oocytes degeneration. Also, we speculated that increased ROS level may trigger tPA and tPA-PAI activities in porcine oocytes matured in vitro.

In the present study, total methanol extracts prepared from Alpinia katsumadai showed significant protective effects against the oxidative stress induced by hydrogen peroxide, UV-C or γ-ray irradiation. These protective effects were substantially increased by treatment with 20~100 μg/ml of the extract. The A. katsumadai total methanol preparation was further fractionated into n-hexane, dichloromethane, ethylacetate, n-butanol and water fractions. Among these five fractions, the ethylacetate and butanol fractions of A. katsumadai showed the strongest protective effects against oxidative stress induced by UV-C and γ-ray irradiation. These fractions also showed high DPPH radical scavenging and lipid peroxidation inhibitory activities. In addition, both fractions displayed cell proliferation activation effects, as evidenced by significant increases in colony formation. Our current data thus suggest that the mechanisms underlying the protective effects of A. katsumadai against oxidative damage may include radical scavenging, protection against cell membrane damage and stimulation of cell proliferation.

Plantago asiatica L. (PA), which is widely distributed in Korea, Japan and China, has traditionally been used as a popular folk medicine for the treatment of liver diseases. A variety of activities of PA was reported, that is hepatoprotective, anti-inflammatory, anti-glycation and anti-oxidant effect. Ferric nitrilotriacetate (Fe-NTA) is a potent nephrotoxic agent and has been reported to induce renal proximal tubular necrosis. In the present study, pretreatment with PA extract (PAE) in Wistar rat followed by Fe-NTA i.p. treatment (13.5 mg Fe/kg body weight) was performed to detect the renal protective effect of PAE. Only Fe-NTA treated group showed increases in the level of serum blood urea nitrogen (BUN) and serum creatinine (Cr), and renal tissue malondialdehyde (MDA), product of lipid peroxidation. Moreover, the level of biomarkers indicate the antioxidants status, reduced glutathione (GSH), glutathione-S-transferase (GST) and glutathione reductase (GR) were decreased. However, PAE pre-treated group showed decreases in the levels of serum BUN, serum Cr and renal tissue MDA in concentration dependent manner and increases in the level of GSH, GST and GR. These results are significantly different (p < 0.05) to the other groups. Our data suggest that PAE may be used as an chemopreventive material against Fe-NTA-mediated renal oxidative stress.

Glutathione S-transferases (GSTs) are multifunctional enzymes that are mainlyinvolved in the xenobiotic metabolism and protection against oxidative damage. Most studies of GSTs in insects have been focused on their role in detoxifying exogenous compounds in particular insecticides. Here, we show the expression profiles of GSTs of the bumblebee Bombus ignitus in response to oxidative stress. We identified a sigma-class GST from B. ignitus (BiGSTS). The BiGSTSgene consists of 4 exons that encode 201 amino acids. Comparative analysis indicates that the predicted amino acid sequence of BiGSTS shares a high identity with the sigma-class GSTs of hymenopteran insects such as Apis mellifera (70% protein sequence identity) and Solenopsis invicta (59% protein sequence identity). Tissue distribution analyses showed the presence of BiGSTS in all tissues examined, including the fat body, midgut, muscle and epidermis. The oxidative stress responses analyzed by quantitative real-time PCR showed that under H2O2 overload, BiGSTS and BiGSTD (identified in our previous study) were upregulated in all tissues examined, including the fat body and midgut of B. ignitus worker bees. Under uniform conditions of H2O2 overload, the expression profile of GSTs and other antioxidant enzyme genes, such as phospholipid-hydroperoxide glutathione peroxidase (Bi-PHGPx) and peroxiredoxins (BiPrx1 and BiTPx1), showed that other antioxidant enzyme genes are acutely induced at 3 h after H2O2 exposure, whereas BiGSTS and BiGSTD are highly induced at 9 h after H2O2 exposure in the fat body of B. ignitus worker bees. These findings indicate that GSTs and other antioxidant enzyme genes in B. ignitusare differentially expressed in response to oxidative stress. Taken together, our findings indicate that BiGSTS and BiGSTD are oxidative stress-inducible antioxidant enzymes that may play a role in oxidative stress response.

In vivo redox reaction is involved in the processes of oxidative diseases. Thus, direct and non-invasive measurement of in vivo free radical reactions in living animals should be essential to understanding the roles of free radicals in pathophysiological phenomena. Electron spin resonance (ESR) technique has been utilized in analysis of free radicals, which are generated through imbalance of in vivo redox status. In vivo ESR/spin probe technique using nitroxide radicals as spin probes was developed for estimation of in vivo free radical reactions in whole living animals. This technique using a probe may become a powerful tool for use in clarifying mechanisms of disease and in monitoring pharmaceutical therapy. The application of ESR was introduced and discussed in this article.

To examine the expression profile of oxidative stress responsive genes in Spodoptera litura, we constructed a cDNA library from S. litura injected with hydrogen peroxide (H2O2). Using a microarray chip composed of 2,964 cDNAs, we screened gene expression at 1, 3, 5, 7, and 9 h post H2O2 injection. Data were clustered into 15 groups of genes that behave similarly across each time course. Seventy-three genes were identified as being at least 2-fold up- or downregulated after treatment with H2O2 in S. litura. We constructed expressed sequence tags (ESTs) for genes that changed at least 2-fold after treatment with H2O2. The functional classification of these ESTs based on Gene Ontology showed that the ESTs are rich in genes involved in oxidoreductase activity (5.7%), defense (14.3%), cellular process (22.9%), and development (17.1%).

Antioxidants partially ameliorated the detrimental effects of reactive oxygen species (ROS) on sperm characteristics during in vitro storage. The objective of the present study was to investigate the single or synergetic antioxidative effect of curcumin and Vit. E on the characteristics of fresh boar sperm during in vitro storage. The sperm viability in curcumin, Vit. E supplementation and curcumin+Vit. E+H2O2 groups remained over 85.0% in 3 hr incubation period, but in 6 hr incubation period, curcumin+Vit. E+H2O2 groups was sharply dropped than those of curcumin and Vit. E group. The membrane intergrity in all evaluated groups except for H2O2 group did not significantly difference in 3 hr incubation period. The viability in curcumin or Vit. E supplementation were significantly increased than in curcumin+H2O2 and Vit. E+H2O2 group in 6 hr incubation period. The percentage of mitochondrial activity and acrosome intergrity obtained similar trends within same incubation periods irrespective of treatment. The lipid peroxidation of spermatozoal plasma membrane ranged from 11.6∼17.5 nM/l×106 and 14.0∼ 19.0 nM/l×106 in 3 hr and 6 hr incubation periods. In conclusion, curcumin or Vit. E rpplementation alone or cooperatively improved sperm viability index (motility, membrane intergrity, viability and survival rates) and fertility index (mitochondria activity, acrosome intergrity and lipid peroxidation) of fresh boar sperm, indicating that curcumin and Vit. E have a antioxidative properties through its scavenging activity against hydrogen peroxide.

In this study, we assessed the effects of dietary supplementation with Ecklonia cava on blood glucose, lipid metabolism, and renal oxidative stress in streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley rats were divided into a normal rat group fed on a control diet and diabetic rats fed on a control diet or supplemented with powder (15% w/w) or water extract of Ecklonia cava (2.5% w/w). Diabetes was induced by a single injection of STZ (60 mg/kg, ip) in citrate buffer. The animals were fed ad libitum with the experimental diet and water for 5 weeks. Dietary supplementation of Ecklonia cava powder and water extract was shown to reduce blood glucose levels in the diabetic rats, and the water extract was more effective than the powder. Dietary supplementation with Ecklonia cava also reduced LDL cholesterol and increased HDL-cholesterol levels in the diabetic rats. Renal glutathione S-transferase activity was increased in the diabetic rats as compared to the normal rats, but reverted to near control values as the result of dietary supplementation with Ecklonia cava. These results show that Eklonia cava exerts an anti-diabetic effect by improving blood glucose concentrations, LDL/HDL-cholesterol ratios, and antioxidative effects on the kidney in diabetic rats.