• Proceedings of the Korean Society of Toxicology Conference
• /
• 2001.10a
• /
• pp.116-117
• /
• 2001

The phthalates have been shown to produce hepatic peroxisome proliferation and certain peroxisome proliferators (PPs) are also known to increase the incidence of liver tumors in rodents. In this study we investigated the correlation between oxidative injury, changes in peroxisomal and microsomal enzymes and tumor formation in PP-treated rats.(omitted)

• Physical Therapy Korea
• /
• v.5 no.1
• /
• pp.63-78
• /
• 1998

The decrease of muscle power and muscle size between twenties and seventies was about 30% and 40% respectively. The loss of muscle mass by aging resulted in the decrease of muscle power. The loss of muscle mass was due to the decrease of number of Type I fiber and Type II fiber and size of each muscle fiber. The aging skeletal muscle didn't show the loss of glycolysis capacity but showed 20% decrease of the oxidative enzymes and muscle vascularization. The vigorous endurance exercise training with graded intensity played a role in the vascular proliferation, increase of activity of oxidative enzymes and improvement of $VO_2$ max. The graded resistance exercise also played a role in the muscle hypertrophy and increase of muscle power, if it performed with adequate intensity and period. The exercise adaptation of aging skeletal muscle prevented it from sarcopenia, provided the activity of daily living with great effect and provided the aging related disease, that is Type II diabetes mellitus, arteriosclerosis, hypertension, osteoporosis and obesity, with great effect.

• Mycobiology
• /
• v.39 no.4
• /
• pp.290-298
• /
• 2011

The ability of benzothiadiazole (BTH) and/or humic acid (HA) used as seed soaking to induce systemic resistance against a pathogenic strain of Fusarium oxysporum was examined in four soybean cultivars under greenhouse conditions. Alone and in combination the inducers were able to protect soybean plants against damping-off and wilt diseases compared with check treatment. These results were confirmed under field conditions in two different locations (Minia and New Valley governorates). The tested treatments significantly reduced damping-off and wilt diseases and increased growth parameters, except the number of branches per plant and also increased seed yield. Application of BTH (0.25 g/L) + HA (4 g/L) was the most potent in this respect. Soybean seed soaking in BTH + HA produced the highest activities of the testes of oxidative enzymes followed by BTH in the four soybean cultivars. HA treatment resulted in the lowest increases of these oxidative enzymes. Similar results were obtained with total phenol but HA increased total phenol more than did BTH in all tested cultivars.

• Biomolecules & Therapeutics
• /
• v.30 no.6
• /
• pp.570-575
• /
• 2022

Stress breaks body balance, which can cause diverse physiological disorders and worsen preexisting diseases. However, recent studies have reported that controllable stress and overcoming from stress reinforce resilience to resist against more intense stress afterwards. In this study, we investigated the protective effect of corticosterone (CORT), a representative stress hormone against hydrogen peroxide (H₂O₂)-induced neuronal cell death and its underlying molecular mechanism in SH-SY5Y cells, a human neuroblastoma cell line. The decreased cell viability by H₂O₂ was effectively restored by the pretreatment with low concentration of CORT (0.03 μM for 72 h) in the cells. H₂O₂-increased expression of apoptotic markers such as PUMA and Bim was decreased by CORT pretreatment. Furthermore, pretreatment of CORT attenuated H₂O₂-mediated oxidative damages by upregulation of antioxidant enzymes via activation of nuclear factor erythroid 2-related factor 2 (Nrf2). These findings suggest that low concentration of CORT with eustressed condition enhances intracellular self-defense against H₂O₂-mediated oxidative cell death, suggesting a role of low concentration of CORT as one of key molecules for resilience and neuronal cell survival.

• Journal of Plant Biotechnology
• /
• v.41 no.2
• /
• pp.73-80
• /
• 2014

Pretreatment of chinese cabbage leaves with $100{\mu}M$ sodium nitroprusside (SNP), a nitric oxide (NO) donor, effectively improved their tolerance to subsequent $2{\mu}M$ paraquat (PQ)-induced oxidative damage. The fresh weight, and chlorophyll and protein contents in primary leaves treated with PQ alone were noticeably reduced over 24 h light incubation. However, these leaf injury symptoms were significantly alleviated with $100{\mu}M$ SNP pretreatment for 3 h prior to PQ exposure. In additions, the increase of the contents of malondialdehyde (MDA) and $H_2O_2$ due to PQ exposure were significantly inhibited by SNP pretreatment. Together with the protective effects of SNP against PQ toxicity in leaves, the changes of ascorbate-glutathione cycle enzymes activities were examined. In the PQ alone treatment, the activities of APX, DHAR, and GR after 6 h incubation were rapidly reduced and showed 19%, 50% and 39% respectively, compared with those of the control. However, the decreases in these enzyme activities were significantly inhibited by SNP pretreatment. As a result, their activities were higher than those of PQ alone treatment by 5 times, 2 times, and 1.5 times, respectively, at 6 h incubation. Thereafter, these enzymes decrease their activities gradually showing high levels than those of PQ alone. Based on the above results, it can be assumed that the activation of ascorbate-glutathione cycle by SNP pretreatment in chinese cabbage leaves exposed to PQ can prevent $H_2O_2$ accumulation, thereby leading to protection against PQ-induced oxidative stress. Also, these results indicate that NO acts as an protectant against PQ stress in the leaves of chinese cabbage.

• The Korean Journal of Food And Nutrition
• /
• v.25 no.1
• /
• pp.123-131
• /
• 2012

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 ${\beta}$-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 ${\mu}g/m{\ell}$ 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.

• Korean Journal of Plant Resources
• /
• v.25 no.2
• /
• pp.184-192
• /
• 2012

The present study was designed to examine the potential antidiabetic and antioxidant effect of ethanol extract from $Prunus$ $mume$ fruit (PME) against alloxan-induced oxidative stress in pancreatic ${\beta}$-cells, HIT-T15. To evaluate the antidiabetic effect of PME, 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazoliu bromide (MTT) cell proliferation assay, lactate dehydrogenase (LDH) release assay, $NAD^+$/NADH ratio and insulin secretion were assessed. We also measured its antioxidant effect against alloxan-induced oxidative stress in the cells by assessing the levels of the 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, PME significantly increased the viability of alloxan-treated cells and lowered LDH leakage. The intracellular $NAD^+$ /NADH ratio and insulin secretion were also increased by 1.5~1.9-fold and 1.4-fold, respectively, after treatment with the PME. The HIT-T15 cells treated with alloxan showed significant decreases in the activities of antioxidant enzymes, while PME significantly elevated the levels of antioxidant enzymes. Based on these results, we suggest that PME could have a protective effect against the cytotoxicity and dysfunction of pancreatic ${\beta}$-cells in the presence of alloxan-induced oxidative stress.

• Toxicological Research
• /
• v.35 no.3
• /
• pp.241-248
• /
• 2019

Pesticide exposure may induce biochemical alterations including oxidative stress and lipid peroxidation. However, in the context of developmental origin of health and disease, putative trans-generational effect of exposure to pesticides are insufficiently studied. We therefore aimed to evaluate the biochemical effect of gestational exposure to four pesticides on female Wistar rats and their offspring at adult age. We studied 30 female nulliparous Wistar rats divided into 5 equal groups. Group 1 served as the control group and received distilled water while group 2, 3, 4 and 5 received orally pesticide 1 (imidacloprid), pesticide 2 (chlorpyrifos), pesticide 3 (imidacloprid + lambda cyhalothrin) and pesticide 4 (oxamyl) respectively once daily throughout gestation at a dose equivalent to 1/10 lethal dose 50. The mothers were followed up until one month post gestation. The offspring were followed up from birth until adult age (12 weeks). In all animals at each time point we evaluated malondialdehyde (MDA), oxidative stress and liver function enzymes. There was similar variation of total body weight in all the groups during and after gestation. However, Female Wistar rats of the exposed groups had significant alterations in liver SOD (-30.8% to +64.1%), catalase (-38.8% to -85.7%) and GSH (-29.2% to -86.5%) and; kidney catalase (> 100%), GSH (> 100%). Moreover, MDA, alanine transaminase (ALT) and aspartate transaminase (AST) levels were significantly higher in pesticide exposed rats compared to the control group. Similar alterations in antioxidant enzymes, MDA and liver function enzymes were observed in offspring of treated rats evidenced at weaning and persisting until adult age. Exposure to pesticides causes oxidative stress and lipid peroxidation in exposed female Wistar rats and their offspring. The persistence in offspring at adult age suggests transgenerational adverse effects.

• Asian-Australasian Journal of Animal Sciences
• /
• v.17 no.12
• /
• pp.1695-1699
• /
• 2004

The antioxidant enzymes, lipid peroxidation and free radicals assessment were made of the effects of selenium, copper and magnesium on bovine endemic fluorosis under high fluoride, low selenium and low copper productive conditions. Thirty-two beef cattle were selected from high fluoride area, and randomly divided into four groups with eight cattle each as follows: (1) high fluoride control group (HFC); (2) supplemented group with 0.25 mg/kg selenium (HFSe); (3) supplemented group with 15 mg/kg copper (HFCu) and (4) supplemented group with 0.25 mg/kg selenium+15 mg/kg copper+1 mg/kg magnesium (HFSeCuMg) per day for 83 days. Moreover, eight beef cattle were selected from non-high fluoride area as normal control group. Blood samples were collected from cattle on 0 d, 30 d and 83 d respectively, to analyze the enzyme activities and concentration of GSH-px, CAT, SOD, MDA and free radicals. The results showed that the contents of free radicals and MDA in HFC group were significantly higher, and the whole blood GSH-px, CAT, erythrocyte SOD activities were lower than the normal control group. Free radicals, metabolic imbalance and antioxidant disorder therefore, play an important role in fluorosis. However, GSH-px, CAT and SOD activities in HFSe group and HFSeCuMg group at 30 d and 83 d were markedly higher than the same groups at the 0 d and the HFC group at the same time. Likewise, there was a corresponding reduction in the contents of free radicals and MDA. These findings indicated that supplementation with selenium, copper and magnesium elevated high fluoride bovine antioxidant enzymes, and decreased MDA and free radicals contents. But, the activities of supplementation selenium group did not increase until day 83. These results demonstrated that fluorosis was associated with lower serum Se and Cu levels than in the control, and it was therefore concluded that fluorosis is associated with decreased serum levels of these minerals. Long-term high fluoride intake under productive condition enhances oxidative stress in the blood, thereby disturbing the antioxidant defense of cattle. Increased oxidative stress could be one of the mediating factors in the pathogenesis of toxic manifestations of fluoride. It is benefical for high fluoride cattle supplemented with proper selenium, copper and magnesium to increase fluoride excretion and obtain the protective impact of the activity of oxidative enzymes, and to decrease lipid peroxidation and free radicals contents.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.12
• /
• pp.5071-5074
• /
• 2016

Background: Azoxymethane (AOM) is a well-known colon cancer-inducing agent in experimental animals via mechanisms that include oxidative stress in rat colon and liver tissue. Few studies have investigated AOM-induced oxidative stress in rat liver tissue. Red seaweeds of the genera Hypnea Bryodies and Melanothamnus Somalensis are rich in polyphenolic compounds that may suppress cancer through antioxidant properties, yet limited research has been carried out to investigate their anti-carcinogenic and antioxidant influence against AOM-induced oxidative stress in rat liver. Objective: This study aims to determine protective effects of red seaweed (Hypnea Bryodies and Melanothamnus Somalensis) extracts against AOM-induced hepatotoxicity and oxidative stress. Materials and Methods: Sprague-Dawley rats received intraperitoneal injections of AOM, 15 mg/kg body weight, once a week for two consecutive weeks and then orally administered red seaweed (100 mg/kg body-weight) extracts for sixteen weeks. At the end of the experiment all animals were overnight fasted then sacrificed and blood and liver tissues were collected. Results: AOM treatment significantly decreased serum liver markers and induced hepatic oxidative stress as evidenced by increased liver tissue homogenate levels of nitric oxide and malondialdehyde, decreased total antioxidant capacity and glutathione, and inhibition of antioxidant enzymes (catalase, glutathione peroxidase, glutathione S-transferase, glutathione reductase and superoxide dismutase). Both red seaweed extracts abolished the AOM-associated oxidative stress and protected against liver injury as evidenced by increased serum levels of liver function markers. In addition, histological findings confirmed protective effects of the two red seaweed extracts against AOM-induced liver injury. Conclusion: Our findings indicate that red seaweed (Hypnea Bryodies and Melanothamnus Somalensis) extracts counteracted oxidative stress-induced hepatotoxicity in a rat model of colon cancer.