Raphanus sativus extract protects against Zearalenone induced reproductive toxicity, oxidative stress and mutagenic alterations in male Balb/c mice

Zearalenone (ZEN) is a non-steroidal estrogenic mycotoxin produced by several species of Fusarium in cereals and agricultural products. It has been implicated in several mycotoxicosis in farm animals and in humans. There is unequivocal evidence of reproductive toxicity of ZEN in male mice although the mechanism of action is unknown. Several reports suggest that exposure to ZEN resulted in oxidative stress, genotoxicity and perturbation of reproductive parameters. Therefore, the aim of the current study was to evaluate the protective effects of aqueous extract of Raphanus sativus growing in Tunisia against ZEN-induced reproductive toxicity and oxidative stress. Fifty male Balb/c mice were divided into five groups and treated for 28 days as follows: the control group, olive oil-treated groups, another treated with ZEN (40 mg/kg b.w), the last one treated with R. sativus extract alone (15 mg/kg b.w) and the other with ZEN + R. sativus extract. Testis samples were collected for the epididymal sperm count, testosterone concentration, and MDA level, GPx, CAT and SOD activities. Blood samples were collected for different biochemical analyses. Also, RAPD-PCR method was performed to assess the antigenotoxic effect of the extract in germ cells. The results indicated that ZEN-induced toxicological effects in accordance to those reported in the literature: decreasing in the sperm number, testosterone level and antioxidant enzyme status. The RAPD-PCR analysis revealed an alteration in the DNA bands patterns between control and ZEN-treated mice. The extract alone, rich in many antioxidant compounds, was safe and succeeded in counteracting the oxidative stress and protect against the toxicity resulting from ZEN.     

丙戊酸钠对重度烫伤大鼠心肌保护作用及其机制研究

目的研究丙戊酸钠(抗癫痫药)对重度烫伤大鼠心肌保护作用及其机制。方法 98只♂SD大鼠,随机分为4组:①假烫组、②烫伤组、③烫伤+二甲基二乙酸(2M2P)组和④烫伤+丙戊酸钠(VPA)组,80℃水浴(假烫组37℃),造成50%总体表面积(TBSA)Ⅲ度烫伤。③、④组分别于烫伤后,即刻皮下注射2M2P、VPA300 mg.kg-1。分别于烫伤后2,6 h腹主动脉取血,测定磷酸肌酸激酶同工酶(CK-MB)变化;然后处死大鼠观察心肌病理变化;检测心肌热休克蛋白(HSP70)表达。结果烫伤大鼠血浆CK-MB水平持续升高,于伤后6 h,VPA组的血浆CK-MB水平(U.L-1)显著低于烫伤组(4398.0±1273.8 vs5438.0±987.9,P<0.01)和2M2P组(4398.0±1273.8 vs 5198.0±1097.3,P<0.01),HSP70表达明显高于烫伤组和2M2P组。病理观察显示,VPA组的心肌损伤轻于烫伤组和2M2P组。结论 VPA改善烫伤休克大鼠心肌酶学指标和组织学损伤,其机制可能与其促进保护性蛋白HSP70表达增多有关。     

Protective role of phosphatidylcholine against cisplatin-induced renal toxicity and oxidative stress in rats

Although cisplatin is widely used in the treatment of cancers, clinical use of cisplatin is limited due to its nephrotoxicity. Pathophysiological mechanism of cisplatin-induced renal toxicity is a complex process and has not been fully understand. Reactive oxygen species (ROS) and oxidative stress have been presumed to be involved in this damage process. Phosphatidylcholine (PC) has antioxidant effect and prevents oxidative stress. Therefore, the present study aimed to investigate potential protective effects of PC on cisplatin-induced renal damage in rat. We examined the protective effects of PC on cisplatin-induced renal damage by assessment of serum creatinine, BUN, lipid peroxidation, total glutathione, glutathione peroxidase activity, catalase activity, superoxide dismutase activity and histophathological changes. PC ameliorated cisplatin-induced increases in serum creatinine, urea and oxidative stress. PC also decreased tubular degeneration and hypertrophy of glomeruli. PC may have a protective effect against cisplatin-induced nephrotoxicity in rats via enhancing antioxidant enzyme activity.     

Protective effect of extract of Crataegus pinnatifida pollen on DNA damage response to oxidative stress

The protective effect of extract of Crataegus pinnatifida (Rosaceae) pollen (ECPP) on the DNA damage response to oxidative stress was investigated and assessed with an alkaline single-cell gel electrophoresis (SCGE) assay and pBR322 plasmid DNA breaks in site-specific and non-site-specific systems. Total phenolic content, total flavonoid content, individual phenolic compounds, antioxidant activities (1,1-diphenyl-2-picrylhydrazyl (DPPH), radical scavenging activity, FRAP, and chelating activity) were also determined. The results showed that ECPP possessed a strong ability to protect DNA from being damaged by hydroxyl radicals in both the site-specific system and the non-site-specific system. It also exhibited a cytoprotection effect in mouse lymphocytes against H₂O₂-induced DNA damage. These protective effects may be related to its high total phenolic content (17.65 ± 0.97 mg GAE/g), total flavonoid content (8.04 ± 0.97 mg rutin/g), strong free radical scavenging activity and considerable ferrous ion chelating ability (14.48 ± 0.21 mg Na₂EDTA/g).     

Sodium selenite and vitamin E in preventing mercuric chloride induced renal toxicity in rats

This study aims to investigate improving effects of sodium selenite and/or vitamin E on mercuric chloride-induced kidney impairments in rats. Wistar male rats were exposed either to sodium selenite (0.25 mg/kg day), vitamin E (100 mg/kg day), sodium selenite + vitamin E, mercuric chloride (1 mg/kg day), sodium selenite + mercuric chloride, vitamin E + mercuric chloride and sodium selenite + vitamin E + mercuric chloride for 4 weeks. Mercuric chloride exposure resulted in an increase in the uric acid, creatinine, blood urea nitrogen and malondialdehyde (MDA) levels and a decrease in the superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities. Histopathological changes were detected in kidney tissues in mercuric chloride-treated groups. A significant decrease in the uric acid, creatinine, blood urea nitrogen and MDA levels and a significant increase in the SOD, CAT and GPx activities were observed in the supplementation of sodium selenite and/or vitamin E to mercuric chloride-treated groups.Conclusively, sodium selenite, vitamin E and vitamin E + sodium selenite significantly reduce mercuric chloride induced nephrotoxicity in rats, but not protect completely.     

Protective roles of onion and garlic extracts on cadmium-induced changes in sperm characteristics and testicular oxidative damage in rats

Cadmium (Cd) is known to exert gonadotoxic and spermiotoxic effects. The present study was performed to assess the possible protective roles of onion (Allium cepa Linn) and garlic (Allium sativum Linn) extracts on Cd-induced testicular damage and spermiotoxicity. The control group received double distilled water; Cd group received Cd (1.5mg/100g BW/day) orally; extract-treated groups were pre-treated with varied doses of onion and/or garlic extract (0.5ml and 1.0ml/100g BW/day) orally for one week and then simultaneously challenged with Cd (1.5mg/100g BW/day) for additional three weeks. Testicular tissue oxidant/antioxidant status and sperm characteristics were determined. Cd caused a marked (p<0.001) rise in testicular lipid peroxidation (LPO) and glutathione S-transferase (GST) levels whereas glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and alkaline phosphatase (ALP) levels were decreased. Cd intoxication significantly (p<0.001) decreased epididymal sperm concentration and sperm progress motility, increased percent total sperm abnormalities and live/dead count. Both extracts successfully attenuated these adverse effects of Cd. Onion extract offers a dose-dependent protection. Our study demonstrated that aqueous extracts of onion and garlic could proffer a measure of protection against Cd-induced testicular oxidative damage and spermiotoxicity by possibly reducing lipid peroxidation and increasing the antioxidant defence mechanism in rats.     

Effects of acute alcohol consumption and vitamin E co-treatment on oxidative stress parameters in rats tongue

The aim of this study was to evaluate the effects of acute alcohol consumption and vitamin E co-treatment upon oxidative stress parameters in rats tongue. Thirty-eight, Wistar rats were separated into five groups (alcohol, alcohol/vitamin E, control, Tween, vitamin E). Alcohol and alcohol vitamin E groups had the standard diet, and 40% alcohol on drinking water. Other groups were fed with the same standard diet and water ad libitum. Vitamin E was given by gavage to vitamin E and alcohol/vitamin E rats twice a week. Alcohol and control groups were subjected to saline gavage and Tween group to 5% Tween 80 solution, the vitamin E vehicle. At day 14, the animals were anesthetized and specimens were obtained from tongue. Lipid peroxidation (TBARS), protein oxidative damage, catalase (CAT) and superoxide dismutase (SOD) activities were quantified. Alcohol group decreased TBARS in relation to control group and alcohol vitamin-treated animals decreased TBARS when compared to Tween and vitamin E groups. SOD activity was lower and CAT activity was higher in animals treated with both alcohol and vitamin E. These results suggest that short-term alcohol consumption decreases lipid peroxidation levels. Alternatively, alcohol/vitamin E group increased CAT, showing the toxicity of this association.     

Protective role of vitamin E on nickel and/or chromium induced oxidative stress in the mouse ovary

In the present study, we report the invivo effects of nickel chloride (NiCl₂; 8 and 16 mg/kg body weight) and/or potassium dichromate (K₂Cr₂O₇; 5 and 10 mg/kg body weight) in the ovary of adult mice. The protective role of vitamin E (2 mg/kg body weight) along with their combination was also studied. Nickel and/or chromium to mice enhanced the levels of lipid peroxides in the ovary, which was accompanied by a significant decline in the levels of protein, glutathione, total ascorbic acid and activities of superoxide dismutase and catalase. Supplementation of vitamin E along with NiCl₂ + K₂Cr₂O₇ significantly lowered the levels of lipid peroxidation and enhanced the antioxidant status. Findings of the present study suggest that vitamin E exerts its protective effect against nickel and/or chromium induced toxicity by preventing lipid peroxidation and protecting antioxidant system in the mouse ovary.     

Effect of vitamin E and C supplementation on oxidative damage and total antioxidant capacity in lead-exposed workers

The molecular response of the antioxidant system and the effects of antioxidant supplementation against oxidative insult in lead-exposed workers has not been sufficiently studied. In this work, antioxidants (vitamin E 400 IU + vitamin C 1 g/daily) were supplemented for one year to 15 workers exposed to lead (73 μg of lead/dl of blood) and the results were compared with those on 19 non-lead exposed workers (6.7 μg of lead/dl). Lead intoxication was accompanied by a high oxidative damage and an increment in the erythrocyte antioxidant response due to increased activity of catalase and superoxide dismutase. Antioxidant supplementations decreased significantly the oxidative damage as well as the total antioxidant capacity induced by lead intoxication with reduction of the antioxidant enzyme activities. We conclude that antioxidant supplementation is effective in reducing oxidative damage and induces modifications in the physiopathological status of the antioxidant response in lead-exposed workers.     

单宁酸对糖尿病模型大鼠肾脏氧化应激水平及炎性因子表达的抑制作用

目的 观察单宁酸对糖尿病模型大鼠抗氧化能力的影响及对机体微炎症状态的改善作用.方法 选择6周龄健康雄性Wistar大鼠68只,随机选取其中8只作为正常对照组,其余60只给予高糖高脂饲料喂养4周后以链脲佐菌素（STZ）按52 mg/kg单次腹腔注射制造糖尿病大鼠模型,造模成功的大鼠进一步随机分为模型组、氨基胍组、单宁酸低剂量组、单宁酸高剂量组,各15只.氨基胍组及单宁酸低、高剂量组分别腹腔注射氨基胍40 mg/（kg·d）及单宁酸[20、30 mg/（kg·d）],正常对照组和模型组给予0.9％氯化钠注射液[30 mg/（kg·d）],10周后处死大鼠取材.化学比色法检测各组大鼠血清及肾皮质丙二醛含量及谷胱甘肽过氧化物酶（GSH-Px）、超氧化物歧化酶（SOD）、过氧化氢酶（CAT）活性;酶联免疫吸附测定法检测肾组织匀浆8-羟基脱氧鸟苷（8-OHdG）含量、血清C反应蛋白（CRP）水平;免疫组织化学检测肾组织细胞间黏附分子1（ICAM-1）、单核细胞趋化蛋白1（MCP-1）的蛋白表达,逆转录-聚合酶链反应检测肾组织ICAM-1、MCP-1 mRNA表达.结果 单宁酸低、高剂量组大鼠血清丙二醛含量明显低于模型组[（23.5±8.5）、（19.8±5.3） μmol/L比（35.5±14.6） μmol/L]（P＜0.05或P＜0.01）,GSH-Px、总SOD及CAT活性明显高于模型组[GSH-Px：（295 ±58）、（322±52） U/L比（232 ±72） U/L,总SOD：（75±13）、（86±15） U/ml比（49±13） U/ml,CAT：（6.9±2.2）、（7.2±2.9） U/ml比（3.7±1.4） U/ml]（P＜0.05或P＜0.01）;单宁酸低、高剂量组大鼠肾组织匀浆丙二醛含量明显低于模型组[（344±120）、（269±52） μmol/L比（464±62） μmol/L]（P＜0.05或P＜0.01）;单宁酸高剂量组GSH-Px活性明显高于模型组[（32 ±8）U/L比（17±4） U/L]（P＜0.01）;单宁酸低剂量组总SOD活性明显高于模型组[（23±4）U/ml比（17±4） U/ml] （P＜0.05）;单宁酸高剂量组大鼠肾组织8-O     

Protective effect of KR-31378 on oxidative stress in cardiac myocytes

In this study, we investigated whether a novel anti-ischemic KATP opener KR-31378 [(2S,3S,4R)-N"-cyano-N-(6-amino-3,4-dihydro-3-hydroxy-2-methly-2-dimethoxymethly-2H-benzopyran-4-yl)-N'-benzylguanidine] has protective effect against oxidative stress-induced death in heart-derived H9c2 cells. Cell death was induced by BSO, butionine sulfoximine, which inhibits GSH synthesis and subsequently increases reactive oxygen species (ROS) level. Cell death was quantitatively determined by measuring lactate dehydrogenase (LDH) activity and stained by Hoechst 33258. BSO-induced ROS production and mitochondrial membrane potential (MMP) were measured using 2',7'-dichlorofluorescein diacetate oxidation and rhodamine 123, respectively. Both the LDH release and the ROS elevation induced by treatment of H9c2 cells with 10 mM BSO, were significantly decreased by KR-31378. These protective effect and antioxidant effect of KR-31378 appeared to be independent on KATP channel opening. Cells exposed to BSO showed an early reduction in MMP, and this reduction in MMP was significantly reversed by treatment with KR-31378. Caspase-3 activity in BSO treated H9c2 cells was remarkably increased, and this increased caspase-3 activity was significantly reversed by KR-31378. In conclusion, our results suggest that KR-31378 can produce cardioprotective effect against oxidative stress-induced cell death through antioxidant mechanism.     

Well-trained,healthy triathletes experience no adverse health risks regarding oxidative stress and DNA damage by participating in an ultra-endurance event

Also physical exercise in general is accepted to be protective, acute and strenuous exercise has been shown to induce oxidative stress. Enhanced formation of free radicals leads to oxidation of macromolecules and to DNA damage. On the other hand ultra-endurance events which require strenuous exercise are very popular and the number of participants is continuously increasing worldwide.     

Protective effect of Corchorus olitorius leaves on sodium arsenite-induced toxicity in experimental rats

The present study was undertaken to evaluate the protective effect of aqueous extract of Corchorus olitorius leaves (AECO) against sodium arsenite-induced toxicity in experimental rats. The animals exposed to sodium arsenite at a dose of 10 mg/kg body weight p.o. for 10 days exhibited a significant inhibition (p < 0.01) of hepatic and renal antioxidant enzymes namely superoxide dismutase, catalase, glutathione-S-transferase, glutathione peroxidase and glutathione reductase. In addition, arsenic intoxication significantly decreased (p < 0.01) the level of reduced glutathione and increased (p < 0.01) the levels of oxidized glutathione and thiobarbituric acid reactive substances in selected tissues. Treatment with AECO at doses of 50 and 100 mg/kg body weight p.o. for 15 days prior to arsenic intoxication significantly improved hepatic and renal antioxidant markers in a dose dependant manner. AECO treatment also significantly reduced the arsenic-induced DNA fragmentation of hepatic and renal tissues. Histological studies on the ultrastructural changes of liver and kidney supported the protective activity of the AECO. The results concluded that the treatment with AECO prior to arsenic intoxication has significant role in protecting animals from arsenic-induced hepatic and renal toxicity.     

Protective effect of N-acetylcysteine on bisphenol A-induced cognitive dysfunction and oxidative stress in rats

Bisphenol A (BPA) is commonly used as a monomer in polycarbonate plastics. The present study was designed to investigate the effect of BPA on cognitive functions and oxidative stress in the brain tissue of rats and if co-administration of N-acetylcysteine (NAC), an antioxidant, can modulate the effect of BPA on cognitive functions and prevent any possible oxidative stress. The BPA was administered per orally (p.o) in two doses 2 and 20 μg/kg for 28 days. Cognitive functions were assessed using step-down latency (SDL) on a passive avoidance apparatus and spatial navigation task on Morris water maze. Oxidative stress was assessed by examining brain malondialdehyde (MDA) and reduced glutathione (GSH) levels. A significant reduction in SDL, and prolongation of latency in spatial navigation task were observed in BPA (2 and 20 μg/kg) treated group as compared to control group. The co-administration of NAC (100 mg/kg, p.o) antagonized the effect of BPA on SDL and spatial navigation test. NAC treatment also attenuated the BPA-induced increased MDA levels and decreased GSH levels in brain. Results of the present study show that NAC has potential to reverse cognitive dysfunction and oxidative stress induced by BPA exposure in rats.     

Prophylactic effect of N-acetylcysteine against sodium fluoride-induced blood oxidative stress in mice

Ninety female Balb/c mice were used. The animals were allocated to evenly six groups. While the first group was maintained as control, Groups 3, 4, 5, and 6 were administered 750 ppm, 1500 ppm, 3000 ppm, and 6000 ppm of N-acetylcysteine, respectively, for a period of 15 days. After day 15, Groups 2–6 were administered sodium fluoride, containing 100 ppm fluoride in drinking water, for another 15 days. Plasma malondialdehyde (MDA) levels and erythrocyte superoksid dismutase (SOD) and catalase (CAT) activities were determined at the beginning of the trial and on days 15 and 30. According to the data obtained in the present study, N-acetylcysteine, when administered at the indicated doses, did not produce a significant alteration in any of the three parameters investigated. On the other hand, while the plasma MDA level was determined to have increased significantly, erythrocyte SOD and CAT activities were ascertained to have decreased significantly in the group, which was administered sodium fluoride alone on day 30. In the groups, which were administered N-acetylcysteine prior to sodium fluoride, however, it was observed that, after sodium fluoride administration, plasma MDA levels and erythrocyte SOD and CAT activities drew closer to the values of the control group.     

Curcumin protects rats against gentamicin-induced nephrotoxicity by amelioration of oxidative stress,endoplasmic reticulum stress and apoptosis

ContextGentamicin (GM) is an aminoglycoside antibiotic which is commonly used against Gram-negative bacterial infection; however, serious complications including nephrotoxicity could limit its clinical use.ObjectiveThe present study examined the protective effects of curcumin (CUR) on endoplasmic reticulum (ER) stress-mediated apoptosis through its antioxidative property in GM-induced nephrotoxicity in rats.Materials and methodsMale Sprague-Dawley rats (n = 3) were divided into six groups to receive normal saline (control), GM (100 mg/kg/day), co-treatment with GM and CUR (100, 200 and 300 mg/kg/day) and CUR (200 mg/kg/day) alone for 15 days by gavage feeding. Then, the renal function, kidney injury as well as oxidative stress, antioxidative markers and ER stress-mediated apoptosis were evaluated.ResultsPre-treatment of CUR rescued the nephrotoxicity in GM-treated rats. Several nephrotoxicity hallmarks were reversed in the CUR-pre-treatment group. At the dose of 200 mg/kg/day, it could significantly lower serum creatinine (from 0.95 to 0.50 mg/dL), blood urea nitrogen (from 35.00 to 23.50 mg/dL) and augmented creatinine clearance (from 0.83 to 1.71 mL/min). The normalized expression of oxidative stress marker, malondialdehyde was decreased (from 13.00 to 5.98) in line with the increase of antioxidant molecules including superoxide dismutase (from 5.59 to 14.24) and glutathione (from 5.22 to 12.53). Furthermore, the renal ER stress and apoptotic protein biomarkers were lowered in CUR treatment.Discussion and conclusionsOur findings pave the way for the application of CUR as a supplement in the prevention of nephrotoxicity and other kidney diseases in the future.     

Protective effects of Iranian Achillea wilhelmsii essential oil on acetaminophen-induced oxidative stress in rat liver

Abstract

Context: Achillea wilhelmsii C. Koch (Asteraceae) is widely used in Iranian traditional medicine.

Objective: This in vivo study evaluates the hepatoprotective role of Iranian A. wilhelmsii oils against acetaminophen-induced oxidative damages in rats.

Materials and methods: The animals were divided into five groups: in negative control and control groups, the DMSO and 500?mg/kg acetaminophen were i.p. injected, respectively. In treatment groups, 100 and 200?mg/kg oils and 10?mg/kg BHT were given i.p. immediately after acetaminophen administration. Then, the hepatic oxidative/antioxidant parameters such as lipid peroxidation (LP), glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), and ferric reducing ability of plasma (FRAP) were measured in time intervals (2, 4, 8, 16, and 24?h) after administrations confirmed by histophatological consideration at 24?h.

Results: The results indicated that acetaminophen caused a significant elevation in SOD activity (8–24?h) and LP and FRAP levels (4?h) paralleled with significant decline in GSH level (4 and 8?h). The apparent oxidative injury was associated with evident hepatic necrosis confirmed in histological examination. The presences of A. wilhelmsii oils (100 and 200?mg/kg) with acetaminophen mitigated significantly the rise in SOD, LP, and FRAP levels and restored the GSH compared with the group treated with acetaminophen. These were confirmed by histological examination indicating the hepatic necrosis reversal by the oils.

Discussion and conclusion: It can be concluded that concomitant administration of A. wilhelmsii oils with acetaminophen may be useful in reversing the drug hepatotoxicity.     

Oxidative stress and oxidative damage in chemical carcinogenesis

Reactive oxygen species (ROS) are induced through a variety of endogenous and exogenous sources. Overwhelming of antioxidant and DNA repair mechanisms in the cell by ROS may result in oxidative stress and oxidative damage to the cell. This resulting oxidative stress can damage critical cellular macromolecules and/or modulate gene expression pathways. Cancer induction by chemical and physical agents involves a multi-step process. This process includes multiple molecular and cellular events to transform a normal cell to a malignant neoplastic cell. Oxidative damage resulting from ROS generation can participate in all stages of the cancer process. An association of ROS generation and human cancer induction has been shown. It appears that oxidative stress may both cause as well as modify the cancer process. Recently association between polymorphisms in oxidative DNA repair genes and antioxidant genes (single nucleotide polymorphisms) and human cancer susceptibility has been shown.     

Protective effect of Aquilegia vulgaris (L.) against lead acetate-induced oxidative stress in rats

Oxidative stress has been proposed as a possible mechanism involved in lead toxicity. The current study was carried out to evaluate the antioxidant activity of the ethanol extract of Aquilegia vulgaris (L.) against lead acetate (LA)-induced oxidative stress in male rats. Tested animals were treated orally with A. vulgaris extract (100 ppm) in combination with, before, or after LA treatment (20 ppm). The results indicated that the extract alone did not induce any significant changes in body weight gain, food intake, serum biochemical chemistry or the histological picture of the liver and kidney. However, it increased significantly the level of Glutathione (GSH). On the other hand, LA decreased food intake, body weight gain and induced oxidative stress as indicated by the significant changes in serum biochemical parameters and histological picture of liver and kidney and increased lipid peroxide and reduces GSH levels in liver tissues. The extract succeeded to improve the histological pictures of liver and kidney and the biochemical parameters towards the normal values of the control. Moreover, this improvement was pronounced in the animals treated with the extract after LA intoxication.     

Protective effects of kahweol and cafestol against hydrogen peroxide-induced oxidative stress and DNA damage

There is an increasing evidence that oxidative stress is implicated in the processes of inflammation and carcinogenesis. It has been shown that kahweol and cafestol, coffee-specific diterpenes, exhibit chemoprotective effects. This study investigated the effects of kahweol and cafestol, coffee-specific diterpenes, on the hydrogen peroxide (H(2)O(2))-induced oxidative stress and DNA damage in NIH3T3 cells. When the cells were treated with kahweol or cafestol, cytotoxicity, lipid peroxidation, and reactive oxygen species production induced by H(2)O(2) were markedly reduced in a dose-dependent manner. Moreover, kahweol and cafestol were shown to be highly protected against H(2)O(2)-induced oxidative DNA damage as determined by the Comet (single cell gel electrophoresis) assay and the measurement of 8-oxoguanine content in NIH3T3 cells. Kahweol and cafestol also protected hydroxyl radical-induced 2-deoxy-d-ribose degradation by ferric ion-nitrilotriacetic acid and H(2)O(2). In addition, kahweol and cafestol efficiently removed the superoxide anion generated from the xanthine/xanthine oxidase system. These results suggest that kahweol and cafestol are effective in protecting against H(2)O(2)-induced oxidative stress and DNA damage, probably via scavenging free oxygen radicals, and that kahweol and cafestol act as antioxidants.