Prevention of cognitive impairments and neurodegeneration by Khamira Abresham Hakim Arshad Wala

Khamira Abresham Hakim Arshad Wala (KAHAW) is an effective and potent cardiac tonic with well-known antioxidant properties. The extensive use of this preparation in Indian system of Unani medicine led us to hypothesize that the pretreatment of this drug to male Wistar rats would prevent cognitive and neurobehavioral impairments. The cognitive impairment was developed by giving single intracerebroventricular injection of 1.5 mg/kg body weight of streptozotocin (STZ) bilaterally. An increased latency and path length was observed in cognitive, i.e. STZ group as compared to sham group and these were restored significantly in STZ group pretreated with KAHAW (700 mg/kg body weight for 15 days). The activity of antioxidant enzymes, viz. glutathione reductase, glutathione S-transferase, glutathione peroxidase, and superoxide dismutase was decreased in STZ group as compared to sham group and pretreatment of STZ group with KAHAW has protected their activities significantly. Moreover, the significantly depleted content of reduced glutathione and significantly elevated level of thiobarbituric acid reactive substances (TBARS) in STZ group were protected significantly with KAHAW. The study concludes that the therapeutic intervention of KAHAW may be used to prevent or to decrease the deterioration of cognitive function and neurobehavioral activities, often associated with the generation of free radicals.     

Antioxidant effect of Cytisus scoparius against carbon tetrachloride treated liver injury in rats

The study was aimed to investigate the antioxidant activity of Cytisus scoparius L. (Family: Leguminosae) on CCl(4) (carbon tetrachloride) treated oxidative stress in Wistar albino rats. CCl(4) injection induced oxidative stress by a significant rise in serum glutamate oxaloacetate transaminases (SGOT), serum glutamate pyruvate transaminases (SGPT), lactate dehydrogenase (LDH) and thiobarbituric acid reactive substances (TBARS) along with reduction of superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione-s-transferase (GST) and glutathione reductase (GRD). Pretreatment of rats with different doses of plant extract (250 and 500mg/kg) significantly lowered SGOT, SGPT, LDH and TBARS levels against CCl(4) treated rats. GSH and hepatic enzymes like SOD, CAT, GPx, GRD, and GST were significantly increased by treatment with the plant extract, against CCl(4) treated rats. The activity of extract at the dose of 500mg/kg was comparable to the standard drug, silymarin (25mg/kg). Based on these results, it was observed that Cytisus scoparius extract protects liver from oxidative stress induced by CCl(4) in rats and thus helps in evaluation of the traditional claim on this plant.     

Influence of tetrahydrocurcumin on erythrocyte membrane bound enzymes and antioxidant status in experimental type 2 diabetic rats

Curcuma longa (Zingiberaceae) has been used traditionally as antidiabetic and has been proven scientifically to possess high antioxidant activity and anticancer properties. The active components of Curcuma longa such as curcumin and tetrahydrocurcumin (THC), a major colourless metabolite of curcumin also possesses antidiabetic, antiinflammatory and antioxidant activity. In the present study the effect of THC and curcumin on erythrocyte membrane bound enzymes and antioxidants activity in streptozotocin (STZ) and nicotinamide induced type 2 diabetic model was investigated. Oral administration of THC at 80 mg/kg body weight to diabetic rats for 45 days. The effect of THC and curcumin on glucose, insulin, haemoglobin, glycosylated haemoglobin, thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), catalase (CAT), glutathione peroxide (Gpx), glutathione-S-transferase (GST), reduced glutathione (GSH) and membrane bound enzymes were studied. The effect of THC was compared with curcumin. The levels of blood glucose, glycosylated haemoglobin, erythrocyte TBARS, were increased significantly whereas the level of plasma insulin and haemoglobin, erythrocyte antioxidants (SOD, CAT, GPx, GST and GSH), membrane bound total ATPase, Na(+)/K(+)-ATPase, Ca(2+)-ATPase, Mg(2+)-ATPase were decreased significantly in diabetic rats. Administration of THC and curcumin to diabetic rats showed decreased level of blood glucose, glycosylated haemoglobin and erythrocyte TBARS. In addition the levels of plasma insulin, haemoglobin, erythrocyte antioxidants and the activities of membrane bound enzymes also were increased in THC and curcumin treated diabetic rats. These biochemical observations were supplemented by histopathological examination of pancreas section. The present study indicates that the THC possesses a significant beneficial effect on erythrocyte membrane bound enzymes and antioxidants defense in addition to its antidiabetic effect.     

Action of Hygrophila auriculata against streptozotocin-induced oxidative stress

Hygrophila auriculata (K. Schum.) Heine (Family: Acanthaceae) is a wild herb widely used in 'Ayurveda' as 'Rasayana' drug for treatment of various disorders. Treatment of diabetic rats with aerial parts of Hygrophila auriculata extract (HAEt, 100 and 250 mg/kg body weight) for 3 weeks showed significant reduction in blood glucose, thiobarbituric acid reactive substances (TBARS) and hydroperoxide in both liver and kidney. The treatment with HAEt significantly increased the glutathione (GSH), glutathione peroxidase (GPx), glutathione S-transferase (GST) and catalase (CAT) in the drug-treated group, which is comparable to the control group. HAEt and glibenclamide-treated rats also showed decreased lipid peroxidation that is associated with increased activity of superoxide dismutase (SOD) and catalase. The ability of HAEt on tissue lipid peroxidation and antioxidant status in diabetic animals has not been studied before. The result of this study thus shows that HAEt possesses significant antidiabetic activity along with potent antioxidant potential in diabetic conditions.     

Protective effect of Bojungikki-tang, a traditional herbal formula, against alcohol-induced gastric injury in rats

Ethnopharmacological evidence

Oxidative stress plays an important role in the pathogenesis of ethanol-induced acute gastric mucosal injury. Bojungikki-tang (Hochuekkito in Japanese, Bu-zhong-yi-qi-tang in Chinese) is a traditional herbal formula used in Korea, Japan, and China to treat allergic diseases and gastrointestinal disorders. However, the mechanism responsible for its actions has not been investigated experimentally.

Aim of the study

The aims of this study were to investigate whether Bojungikki-tang water extract (BJITE) has protective effects against ethanol-induced acute gastric injury in rats and to perform an acute toxicity study to evaluate its safety.

Materials and methods

In this rat model, gastric mucosal injury was imposed by oral administration of 5 mL/kg body weight of absolute ethanol. BJITE at one of two doses (200 or 400 mg/kg body weight) was administered by gavage 2 h before ethanol administration. Gastric tissues were collected and analyzed to assess the gastric injury index, and content or activity of catalase, superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), glutathione-S-transferase (GST), glutathione reductase (GR), and glutathione peroxidase (GPx).

Results

Acute administration of ethanol significantly increased the gastric injury index concomitantly with an increase in MDA and GSH content, and a decrease in the activities of catalase, GST, GR, GPx, and SOD. Pretreatment with 200 or 400 mg/kg BJITE attenuated ethanol-induced gastric mucosal injury; this was accompanied by an increase in the content or activity of PGE₂, catalase, GSH, GST, GR, GPx, and SOD, and a decrease in MDA content. In the acute toxicity study, no adverse effects of BJITE were observed at doses up to 2000 mg/kg body weight.

Conclusion

These results indicate that BJITE can partly protect the gastric mucosa from ethanol-induced acute gastric injury and suggest that these protective effects might be induced by increasing the antioxidant status. We suggest that BJITE can be developed as an effective drug for the treatment of acute gastric injury.     

Ferulic acid alleviates lipid peroxidation in diabetic rats

Diabetes mellitus is a metabolic disorder associated with increased formation of free radicals. The objective of our study was to determine whether ferulic acid (FA), a phenolic acid, has any role to play in diabetes induced free radical formation. Diabetes was induced with streptozotocin. The levels of blood glucose, thiobarbituric acid reactive substances (TBARS), hydroperoxides and free fatty acids (FFA) increased in the liver of diabetic animals. The activities of glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) decreased in the liver. Histopathology of pancreas also shows shrunken islets. Supplementation of FA to the diabetic rats resulted in a decrease in the levels of glucose, TBARS, hydroperoxides, FFA and an increase in reduced glutathione (GSH). FA also resulted in increased activities of SOD, CAT, GPx and expansion of pancreatic islets. The effect was much pronounced with lower dose treatment. Thus our study shows that administration of ferulic acid helps in enhancing the antioxidant capacity of these diabetic animals by neutralizing the free radicals formed thereby reducing the intensity of diabetes.     

Cerebroprotective effect of Korean ginseng tea against global and focal models of ischemia in rats

Korean ginseng tea (KGT), prepared from the roots of Panax ginseng, is widely used by Korean people for antistress, antifatigue, and endurance promoting effects. In the present study we evaluated neuroprotective/cerebroprotective actions of KGT in stroke, using rat global and focal models of ischemia. Varied biochemical/enzymatic alterations, produced subsequent to the application of middle cerebral artery (MCAO) and bilateral carotid artery occlusion (BCAO) followed by reperfusion viz. increase in lipid peroxidation (LPO) and decrease in glutathione (GSH), glutathione reductase (GR), catalase (CAT), glutathione-S-transferase (GST), glutathione peroxidase (GPx) and superoxide dismutase (SOD), were markedly reversed and restored to near normal levels in the groups pre-treated with KGT (350 mg/kg given orally for 10 days). It is concluded that the protective action, exhibited by KGT against hypoperfusion/reperfusion induced brain injury, suggests its therapeutic potential in cerebrovascular diseases (CVD) including stroke. These findings are important because: (a) the present treatment strategies for CVD are far from adequate and (b) KGT with wide usage is known to be a safe natural product.     

Beneficial effects of Centella asiatica aqueous extract against arsenic-induced oxidative stress and essential metal status in rats

The efficacy of an aqueous extract of Centella asiatica (100, 200 and 500 mg/kg for 5 consecutive days) was studied in the depletion of arsenic and in the recovery of a few altered biochemical variables in arsenic pre-exposed rats (20 ppm in drinking water for 5 weeks). Exposure to arsenic significantly depleted delta-aminolevulinic acid dehydratase (ALAD) activity, reduced glutathione (GSH) level, superoxide dismutase (SOD) and increased thiobarbituric acid reactive substance (TBARS) activity in red blood cells. Significant depletion of ALAD activity, GSH level, glutathione peroxidase (GPx), SOD and catalase (CAT) activities and an increase in TBARS levels in liver tissues was also noted. There was a significant depletion of SOD, CAT and GPx activities in kidneys and an increased TBARS levels in kidney and brain accompanied by increased arsenic concentration in blood and soft tissues. Treatment with aqueous extract of Centella asiatica provided significant protection against ALAD, GSH and TBARS levels, particularly at doses of 200 and 500 mg. Centella asiatica also provided significant recovery in the inhibited liver ALAD and G6PD activities. Arsenic concentration in blood and soft tissues remained uninfluenced after Centella asiatica administration. The present study thus suggests a beneficial effect of Centella asiatica against arsenic-induced oxidative stress but possesses no chelating property.     

Protection of human HepG2 cells against oxidative stress by the flavonoid epicatechin

Flavanols, such as epicatechin (EC), constitute an important part of the human diet; they can be found in green tea, grapes and cocoa and possess different biological activities such as antioxidant, anti‐inflammatory and anticarcinogenic. This study investigated the potential chemo‐protective effect of EC against oxidative stress induced by tert‐butylhydroperoxide (t‐BOOH) on human HepG2 cells. Cell viability by lactate dehydrogenase assay and markers of oxidative status: reduced glutathione (GSH), malondialdehyde (MDA), reactive oxygen species (ROS), glutathione peroxidase (GPx) and glutathione reductase (GR) were evaluated. Pretreatment of cells with EC for 20 h prevented the enhanced cell damage and GPx and GR activities as well as the decrease in GSH induced by t‐BOOH. The increased ROS generation induced by t‐BOOH was also partly prevented by a pretreatment for 20 h with EC. In addition, pretreatment of cells with EC for 20 h recovered the t‐BOOH‐induced MDA concentration to control values. A pretreatment for 2 h with EC did not reduce cell damage but partly recovered GSH, reduced ROS levels and muffled the increase of GPx and GR after exposure to t‐BOOH. Treatment of HepG2 cells with concentrations of EC in the micromolar range confers a significant protection against oxidative stress. Copyright © 2009 John Wiley & Sons, Ltd.     

基于调控生理状态下抗氧化抗炎水平探讨雷公藤配伍金钱草相杀减毒的生物机制

目的考察生理状态下雷公藤配伍金钱草相杀减毒的生物机制。方法通过对生理状态下小鼠的肝和肾组织抗氧化和部分炎症相关指标的比较分析,探讨二者相杀减毒的生物机制。结果与正常组比较,雷公藤被灌胃给药14 d后,极显著降低了小鼠肝和肾的抗氧化物质谷胱甘肽(GSH)、谷胱甘肽-S-转移酶(GST)、谷胱甘肽过氧化物酶(GPx)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、白介素(IL)-10的水平(P<0.01),并升高了肿瘤坏死因子(TNF)-α水平(P<0.01);与雷公藤单用组比较,雷公藤-金钱草在质量配比为4∶1、2∶1、1∶1、1∶2、1∶4的各配伍组均能显著升高肝和肾的GSH、GST、GPx、SOD、CAT和IL-10的水平(P<0.05或P<0.01),并显著降低TNF-α的水平(P<0.01)。结论雷公藤配伍金钱草对生理状态下的相杀减毒机制,可能与增强靶器官的抗氧化防御并抑制炎症反应有关。     

Gastroprotective and antioxidant effects of usnic acid on indomethacin-induced gastric ulcer in rats

Usnea longissima, a medicinal lichen of Anatolia (Turkey), is used in the treatment of gastric ulcer in local folk medicine. In this paper, the gastroprotective effect of usnic acid (UA) isolated from Usnea longissima was investigated in the indomethacin-induced gastric ulcers in rats at doses of 25, 50, 100 and 200 mg/kg body weight. The gastric lesions were significantly reduced by all doses of UA as compared with the indomethacin (25 mg/kg body weight) treated group. In the stomach tissues of treated animals, the in vivo antioxidant levels were evaluated. The administration of indomethacin caused a significant decrease in the levels of superoxide dismutase (SOD), glutathione peroxidase (GPx) and reduced glutathione (GSH), and an increase in the lipid peroxidation (LPO) level (p < 0.05). The administration of all doses of UA reversed the trend, inducing a significant increase of SOD, GSH and GPx levels and a reduction in LPO level in tissues. However, catalase (CAT), glutathione reductase (GR) and myeloperoxidase (MPx) activities, increased by indomethacin, were found to be lower in the UA- and ranitidine-treated groups. The gastric mucosal constitutive NO synthase (cNOS) and inducible NO synthase (iNOS) activities were also investigated in tissues of UA- (100 mg/kg), ranitidine- (50 mg/kg) and indomethacin-treated rat groups. The administration of UA and ranitidine increased the cNOS activity and lowered the iNOS activity as compared with indomethacin-treated group. These results suggest that the gastroprotective effect of UA can be attributed to its reducing effect on the oxidative damage and neutrophil infiltration in tissues.     

Emblica officinalis causes myocardial adaptation and protects against oxidative stress in ischemic-reperfusion injury in rats

The fruits of Emblica officinalis (Amla) are widely used in the Indian System of Medicine and are believed to increase defense against disease. In the present study, the effects of chronic oral administration of fresh fruit homogenate of Amla on: (i). myocardial antioxidant system and (ii). oxidative stress induced by ischemic-reperfusion injury (IRI) in rat heart were investigated. Fresh amla fruit homogenate, in three different doses (250, 500 and 750 mg/kg) and normal saline (C) were administered orally to Wistar albino rats (120-150 gms) of either sex daily for 30 days. There was reduction in basal myocardial lipid peroxidation, as evidenced by decreased thiobarbituric acid reactive substances (TBARS) level, and augmentation of myocardial endogenous antioxidants, like superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) in the treated rats. Hearts were also subjected to in vitro IRI (9 min of global ischemia, followed by 12 min of reperfusion, Langendorff's mode). Significant myocyte injury and rise in myocardial TBARS along with depletion of SOD, catalase, GSH (reduced glutathione) and GPx occurred in the control group. No significant increase in myocardial TBARS and depletion of antioxidant enzymes were observed in the treated groups. Myocyte injury was evident only in 250 mg/kg group. The results indicate that chronic Emblica officinalis administration causes myocardial adaptation by augmenting endogenous antioxidants and protects rat hearts from oxidative stress associated with ischemic-reperfusion injury.     

含与不含朱砂和雄黄的安宫牛黄丸对大鼠局灶性脑缺血的影响

目的：观察含与不含朱砂和雄黄的安宫牛黄丸对大脑中动脉栓塞模型大鼠脑梗塞面积、脑含水量及过氧化氢酶（CAT）、脂质过氧化物（LPO）、谷胱甘肽过氧化物酶（GPX）、乳酸(LD）含量的影响，探讨安宫牛黄丸中朱砂、雄黄对药效的影响。方法：动物连续灌胃给药3天后，采用大脑中动脉三氯化铁法造成大鼠脑局灶性缺血。分别用TTC染色法、烘干称重法、TBA法和按试剂盒说明书，测定大鼠脑梗塞面积、脑含水量和LPO、CAT、GPX、LD的含量。结果：含与不含朱砂、雄黄的安宫牛黄丸各剂量组大脑中动脉栓塞大鼠脑梗塞面积明显减少；脑缺血侧含水量降低；CAT和GPX含量增加，LPO和LD含量降低。结论：含与不含朱砂、雄黄的安宫牛黄丸对大脑中动脉栓塞大鼠脑组织损伤均有一定的保护作用，两者之间未见显著差异，提示安宫牛黄丸中朱砂、雄黄对大鼠脑缺血梗塞的保护作用未有明显影响。     

Protective effect of Aquilegia vulgaris (L.) on APAP-induced oxidative stress in rats

Rats pretreated with acetaminophen (N-acetyl-p-aminophenol, APAP) (600 mg/kg b.w., p.o.) were administered with ethanol and ethyl acetate extracts as well as with isocytisoside (100 mg/kg b.w., p.o.) obtained from Aquilegia vulgaris (L.) (Ranunculaceae) herb. The substances tested decreased enzymatic, non-enzymatic and uninduced microsomal lipid peroxidation (LPO) in the liver of rats treated with APAP by 18-48%. Activity of the antioxidant enzymes in the liver inhibited by APAP was increased in the majority of groups after administration of the substances tested: catalase (CAT) by 55%, glutathione peroxidase (GPx) by 50%, glutathione reductase (GR) by 35% and glutathione S-transferase (GST) by 60%. Hepatic glutathione level depleted by APAP was only slightly increased by the substances tested. The cytochrome P450 contents, and the activities of NADPH-cytochrome P450 reductase and two monooxygenases were not affected by the extracts and isocytisoside. It can be concluded that the protective ability of the substances tested in APAP-induced liver injury is mediated by amelioration of microsomal lipid peroxidation and restoring antioxidant enzymes activity. Inhibition of enzymes responsible for metabolic activation of APAP is not involved in this process.     

银杏二萜内酯葡胺注射液对大鼠局灶性脑缺血的保护作用

探讨银杏二萜内酯葡胺注射液对大鼠局灶性脑缺血再灌注损伤(MCAO)的保护作用,并探讨其可能的作用机制。雄性SD大鼠140只,随机分为假手术组、模型组、银杏提取物注射液(金纳多,1.0 m L·kg~(-1))、尼莫地平注射液(0.2 mg·kg~(-1))组、银杏二萜内酯葡胺注射液(5.2,2.6,1.3 mg·kg~(-1))组;所有动物手术前4 d尾静脉注射给药(模型组及假手术组给予生理盐水)。除假手术组,其他动物通过右侧大脑中动脉线栓塞法(MCAO)制作局灶性脑缺血再灌注模型。缺血3 h后,所用动物再次尾静脉注射给药。大鼠缺血再灌注后进行神经行为学评分并采用TTC染色法观察脑组织梗死率;测定脑组织匀浆中超氧化物歧化酶(SOD)、谷胱甘肽(GSH)、丙二醛(MDA)、乳酸(LA)含量及脑脊液中Ca~(2+),谷氨酸(Glu),天冬氨酸(Asp)以及磷酸肌酸激酶(CK-BB)和乳酸脱氢酶(LDH)含量的变化。与假手术组相比,模型组大鼠脑梗死率显著增加,神经严重缺损;脑组织匀浆中MDA、LA含量升高,GSH、SOD含量降低;脑脊液中Ca~(2+)浓度降低,Glu和Asp的含量及CK-BB、LDH含量显著升高。与模型组相比,银杏二萜内酯葡胺注射液高、中剂量组能显著减少脑梗死率,改善脑神经功能缺损症状;提高SOD、GSH活性,减少血清中MDA、LA含量;升高脑脊液中Ca~(2+)浓度,减低神经递质Glu和Asp的含量及CK-BB、LDH的含量。银杏二萜内酯葡胺注射液能明显改善模型动物的神经功能缺损,其机制可能与修复血脑屏障,减少自由基,减少细胞外游离钙内流,降低脑脊液中兴奋性氨基酸含量等有关,从而保护脑缺血。     

Protective effects of dietary ginger (Zingiber officinales Rosc.) on lindane-induced oxidative stress in rats

The protective effect of dietary feeding of Zingiber officinales Rosc. (ginger) against lindane-induced oxidative stress was investigated in male albino rats. Oxidative stress was monitored by estimating the extent of lipid peroxidation, activities of the oxygen free radical (OFR) scavenging enzymes superoxide dismutase (SOD) and catalase (CAT) and the status of the glutathione redox cycle antioxidants. Lindane administration (30 mg/kg bw orally for 4 weeks) was associated with enhanced lipid peroxidation and compromised antioxidant defenses in rats fed a normal diet. Concomitant dietary feeding of ginger (1%w/w) significantly attenuated lindane-induced lipid peroxidation, accompanied by modulation of OFR scavenging enzymes as well as reduced glutathione (GSH) and the GSH dependent enzymes glutathione peroxidase (Gpx), glutathione reductase (GR) and glutathione-S-transferase (GST) in these rats. These findings suggest that a diet containing naturally occurring compounds is effective in exerting protective effects by modulating oxidative stress.     

牛黄上清丸对脑缺血保护作用的研究

目的：探讨牛黄上清丸对实验性脑缺血的保护作用及对血液流变学指标的影响。方法：采用大鼠大脑中动脉血栓(MCAO)模型、双侧颈总动脉结扎致脑缺血模型和角叉莱胶加细胞内毒素联合诱导大鼠血瘀证模型,研究牛黄上清丸对实验性脑缺血动物神经体征、脑梗死范围、脑含水量和脑组织中乳酸(LD)、丙二醛(MDA)、过氧化酶(CAT)、谷胱甘肽过氧化物酶(GPx)含量及血液流变学指标的影响。结果：牛黄上清丸3.00,1.50 g·kg-1剂量能明显改变MCAO 大鼠的神经体征,减少其脑梗死范围；可明显降低MCAO及缺血再灌模型大鼠的脑含水量,提高脑组织中抗氧化酶GPx,CAT的活力,降低MDA和LD含量；能够改善血瘀证模型大鼠的血液流变学指标。结论：牛黄上清丸对实验性脑缺血具有保护作用。     

Effect of Curcumin on Hepatic Antioxidant Enzymes Activities and Gene Expressions in Rats Intoxicated with Aflatoxin B1

Twenty‐eight rats were examined in a 5‐week experiment to investigate the effect of curcumin on gene expression and activities of hepatic antioxidant enzymes in rats intoxicated with aflatoxin B1 (AFB₁). The rats were divided into four groups. Rats in 1–4 groups served as control, oral curcumin treated (15 mg/kg body weight), single i.p. dose of AFB₁ (3 mg/kg body weight) and combination of single i.p. dose of AFB₁ with oral curcumin treated, respectively. AFB₁ Liver damage and oxidative stress were evident in untreated AFB₁‐intoxicated rats as indicated by a significant elevation in hepatic transaminases, elevation in lipid peroxide biomarkers (thiobarbituric acid reactive substances; TBARS), reduction of reduced glutathione (GSH) concentration, reduction in the activities of antioxidant enzymes namely catalase (CAT), total superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione‐S‐transferase (GST) and down‐regulation of gene expression of these antioxidant enzymes compared to control. Liver sections of rats intoxicated with AFB₁ showed a disrupted lobular architecture, scattered necrotic cells and biliary proliferation. Administration of curcumin with AFB₁ resulted in amelioration of AFB₁‐induced effects compared to untreated AFB₁‐intoxicated rats via an up‐regulation of antioxidant enzyme gene expression, activation of the expressed genes and increase in the availability of GSH. Copyright © 2014 John Wiley & Sons, Ltd.     

Modulatory influence of Andrographis paniculata on mouse hepatic and extrahepatic carcinogen metabolizing enzymes and antioxidant status

The effects of two doses (50 and 100 mg/kg body wt/day for 14 days) of an 80% hydroalcohol extract of Andrographis paniculata and butylated hydroxyanisole (BHA) were examined on drug metabolizing enzymes, antioxidant enzymes, glutathione content, lactate dehydrogenase (LDH) and lipid peroxidation in the liver of Swiss albino mice (6-8 weeks old). The effect of the extract and BHA were also examined on lung, kidney and forestomach for the activities of glutathione S-transferase (GST), DT-diaphorase (DTD), superoxide dismutase (SOD) and catalase. A significant increase in the levels of acid soluble sulphydryl (-SH) content, cytochrome P450, cytochrome P450 reductase, cytochrome b5 reductase, GST, DTD and SOD were observed at both dose levels of extract treatment while catalase, glutathione peroxidase and glutathione reductase (GR) showed significant increases only at the higher dose in the liver. Both Andrographis treated groups showed a significant decrease in activity of LDH and malondialdehyde (MDA) formation. BHA treated mice showed a significant increase in the levels of cytochrome b(5), GST, DTD, -SH content, GR and catalase in liver; while LDH and MDA levels were reduced significantly compared with their control values. In the lung, SOD, catalase and DTD, in the kidney catalase, DTD and GST, and in the forestomach SOD and DTD showed a significant increase at both dose levels of treatment. In BHA treated mice GST, DTD and catalase were significantly induced in the lung and along with these enzymes SOD was also induced in the kidney. In the case of the forestomach of BHA treated mice GST, DTD and SOD were enhanced significantly. These findings indicate the chemopreventive potential of Andrographis paniculata against chemotoxicity including carcinogenicity.     

Protective effects of water extract of clam on normal and CCl₄-induced damage in primary cultured rat hepatocytes

The objective of this study was to investigate the effects of various concentrations and incubation times of water extract of clam (WEC) on glutathione, its antioxidant and the detoxification defense systems in normal and CCl?-induced oxidative damaged primary rat hepatocytes. This study showed that when the hepatocytes were treated with WEC (0.14 ~ 1.68 mg/ml), the intracellular glutathione (GSH) levels, GSH/GSSG ratio, and the activities of GSH-related enzymes (GPx, GRd, and GST) were higher than those in the control at 24 or 48 hour treatments. However, the lactate dehydrogenase (LDH) leakage and microscopic observations did not differ from those of the control. Yet, when the hepatocytes were pretreated with various concentrations of WEC for 24 hours and then exposed to 5 mM carbon tetrachloride (CCl?) for 1 hour, at concentrations of WEC between 0.42 ~ 1.68 mg/ml, the viabilities, intracellular GSH level, and activities of GST and GPx were significantly increased compared to those of the CCl?-treated control group (p < 0.05). In conclusion, WEC could improve the viability and the capabilities of detoxification and antioxidation in hepatocytes by increasing the GSH level and the activities of GSH-related enzymes.