Evaluation of antioxidant activity of Salix caprea flowers

The study was aimed at evaluating the antioxidant activity of an ethanol extract of Salix caprea L. (Salicaceae) flowers. The extract was found to possess a large amount of polyphenols and also exhibited a high reducing ability. The extract significantly and dose dependently scavenged DPPH, superoxide (O(2) (*-)), hydrogen peroxide (H(2)O(2)) and nitric oxide (NO). At a concentration of 250 microg/mL, 85.04% of DPPH radicals and at 500 microg/mL 45.97%, 17.97% and 56.53% of O(2) (*-), H(2)O(2) and NO, respectively, were scavenged by the S. caprea flower extract. A significant amount of protection was also afforded by the extract in the acute oxidative tissue injury animal model constituted by ferric nitrilotriacetate (FeNTA) induced hepatotoxicity in mice. An intraperitoneal administration of FeNTA at a dose of 9 mg/kg of body weight caused an elevation in hepatic lipid peroxidation (LPO) to 176.90% and a suppression in hepatic glutathione (GSH) content and the activities of antioxidant enzymes namely, catalase (CAT), glutathione reductase (GR) and glutathione peroxidase (GPX) to 46.49%, 64.37%, 41.71% and 48.76%, respectively, of the saline treated control. The pretreatment of mice with S. caprea flower extract at a dose range of 50-150 mg/kg of body weight for 7 days followed by FeNTA treatment caused preservation of all these parameters. The present study indicates that the flowers of S. caprea possess a significant antioxidant and hepatoprotective property, the former being implicated in the latter.     

Ameliorative effects of pycnogenol on carbon tetrachloride-induced hepatic oxidative damage in rats

This study evaluated the putative antioxidant activity of Pycnogenol (PYC) against CCl4-induced hepatic oxidative damage in Sprague-Dawley rats. A single oral dose of CCl4 (1.25 mL/kg) produced significantly increased levels of serum aminotransferase (AST) and alanine aminotransferase (ALT) activities. In addition, increased malondialdehyde (MDA) concentration, reduced glutathione (GSH) content, and decreased catalase, superoxide dismutase (SOD) and glutathione-S-transferase (GST) activities were observed in the hepatic tissues. However, concomitant administration with PYC (10 or 20 mg/kg) significantly improved CCl4-induced hepatic injury, as evidenced by the decline of serum AST and ALT activities in a dose dependent manner. Moreover, PYC reduced MDA concentration and increased GSH levels and catalase, SOD and GST activities in hepatic tissues, indicating that concomitant administration with PYC efficiently prevent the CCl4-induced oxidative damage in rats. The free radical scavenging assay showed that PYC has a dose-dependent scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals. These results indicate that PYC has an antioxidant effect against CCl4-induced hepatic oxidative damage and is useful as a hepatoprotective agent against various liver diseases induced by oxidative stress.     

Antioxidant effect of Inonotus obliquus

The mushroom Inonotus obliquus (Fr.) Pilát (Hymenochaetaceae), has been widely used as a folk medicine in Russia, Poland and most of the Baltic countries. The purpose of this study was to elucidate the antioxidant capacities of Inonotus obliquus. Four extracts from the fungus were evaluated for antioxidant activity against the 1,1-diphenyl-2-picrylhydrazyl (DPPH), superoxide, and peroxyl radicals. The polyphenolic extract had a strong antioxidant activity, and the extract containing triterpenoids and steroids presented a relatively strong antioxidant effect. The polysaccharide extract, however, was inactive. The protective effects of these four extracts were assessed against hydrogen peroxide-induced oxidative stress using a human keratinocyte cell line, HaCaT. Our results show that the polyphenolic extract protected these cells against hydrogen peroxide-induced oxidative stress, while the polysaccharide, triterpenoid and steroid extracts were ineffective. Additionally, the remnant polyphenolic and low molecular weight polysaccharide extracts showed a weakly protective effect at a concentration of 50 microg/ml. Our results indicate that Inonotus obliquus has the capacity to scavenge free radicals at concentrations higher than 5 microg/ml and that the polyphenolic extract can protect cells against oxidative stress.     

Antioxidative and acute anti-inflammatory effects of Campsis grandiflora flower

The present study was undertaken to investigate the antioxidative and anti-inflammatory activities of the extract of the flower of Campsis grandiflora (Thunb.) K. Schum. Exposure of human dermal fibroblasts to 50% EtOH extract of Campsis grandiflora flower (ECG) at 10 and 100 microg/ml showed significant protective effect against hydrogen peroxide (300 microM). ECG not only protected cell survival from H(2)O(2)-induced toxicity, but also inhibited the H(2)O(2)-induced leakage of lactate dehydrogenase (LDH) enzyme release and DNA fragmentation significantly. It was also found that ECG showed scavenging activities of radicals and reactive oxygen species with IC(50) values of 20 microg/ml against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and 52 microg/ml against superoxide radicals in the xanthine/xanthine oxidase system, respectively. Topically applied ECG dose-dependently inhibited arachidonic acid (AA)- and 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced ear edema in mice. Consistent with its antioxidative properties in vitro, the present results suggest the therapeutic potential of ECG for acute skin inflammation that may involve oxidative tissue damage.     

In vitro and in vivo antioxidant activity of alfalfa (Medicago sativa L.) on carbon tetrachloride intoxicated rats

The present study was conducted to determine whether lyophilized aqueous extract of alfalfa, or Medicago sativa L. could exert antioxidant activity against carbon tetrachloride-induced oxidative stress and liver injury in rats. The hepatoprotective activity of alfalfa extract was determined by assessing the levels of serum transaminases, ALP, bilirubin and lipid profile. Further, the effect of the test substance on malondialdehyde (MDA), an end product of lipid peroxidation; antioxidant liver enzyme non-protein sulfhydryl (NP-SH); and total protein (TP) were also studied. Serum transaminase, ALP, bilirubin level, lipid profile and liver MDA were significantly elevated and the antioxidant status in liver NP-SH and TP contents were declined in animals treated with CCl (4) alone. Pretreatment with alfalfa and silymarin for three weeks prior to the administration of CCl (4) significantly prevented the increase in the serum levels of hepatic marker, LDL, VLDL levels enzymes and reduced oxidative stress indicated by elevated NP-SH and TP concentration. The histopathological examination of the livers also showed that the alfalfa extract reduced the incidence of liver lesions induced by CCl (4). The in vitro antioxidant assessment of alfalfa extract on DPPH and carotene-linoleic assays demonstrated a moderate antioxidant potential. Results suggest that the alfalfa extract possesses hepatoprotective and antioxidative stress properties possibly through its antioxidant phytochemical constituents and substantiates its use in various liver disorders as a hepatoprotector.     

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.     

菊花水提液对心脑组织的体内外抗氧化作用

本文以丹参为对照观察菊花水提液对大鼠心、脑组织体外孵育时自发脂质过氧化(LPO)反应的影响;对羟自由基(·OH)引发的小鼠心、脑匀浆和心、脑线粒体膜LPO反应的影响。结果表明菊花水提液对上述过程的抑制作用与丹参相当;小鼠连续灌胃菊花水提液2g·kg-1·d-1、4g·kg-1·d-115d,其心、脑组织LPO反应产物丙二醛含量均显著低于生理盐水组。上述结果表明菊花水提液具有抑制自由基生成及抑制自由基引发的LPO反应的作用。     

Protective effects of Phellinus linteus extract against iron overload-mediated oxidative stress in cultured rat hepatocytes

Phellinus linteus (PL) mushroom has been reported to possess antioxidant activity. The present study was designed to investigate whether an ethanol extract obtained from PL might ameliorate oxidative stress and enhance antioxidant enzyme activities in primary rat hepatocytes, which were overloaded with iron using ferric nitrilotriacetate (FeNTA) complex. FeNTA enables hepatocytes to accumulate substantially redox-active iron and stimulates the production of injurious hydroxyl radicals, which in turn, initiate oxidative stress-mediated cytotoxicity. The results showed that pretreatment of hepatocytes with PL extract (50, 100 and 200 microg/mL) for 24 h significantly reversed FeNTA-induced cell viability loss, lactate dehydrogenase leakage (LDH), lipid peroxidation (LPO) and protein carbonyl formation in a dose-dependent manner. It was further observed that PL extract produced an inhibitory effect on intracellular reactive oxygen species (ROS) formation caused by FeNTA. Concomitantly, the amount of GSH content and the activities of glutathione reductase (GSH Rd) and glutathione peroxidase (GSH Px) in hepatocytes pretreated with PL extract increased substantially compared with those treated with FeNTA alone. These results suggest that PL may be useful in protecting against FeNTA-induced oxidative damage and also be capable of attenuating cytotoxicity of other oxidants.     

Hepatoprotective effect of the aqueous extract of Flemingia macrophylla on carbon tetrachloride-induced acute hepatotoxicity in rats through anti-oxidative activities

This study investigated the protective effect of the aqueous extract of Flemingia macrophylla (AFM) against hepatic injury induced by CCl(4). Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were detected as biomarkers in the blood to indicate hepatic injury. Product of lipid peroxidation (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and reduced glutathione (GSH) contents were evaluated for oxidative stress in hepatic injury. Moreover, histopathological observation was assayed for the degree of hepatic injury. After oral administration of AFM, 0.5 g/kg and 1.0 g/kg doses significantly decreased ALT and AST, attenuated the histopathology of hepatic injury, ameliorated oxidative stress in hepatic tissue, and increased the activities of CAT, SOD and GSH-Px. The hepatoprotective effect of daidzein and genistein were consistent to that of AFM. This study demonstrated for the first time that AFM has hepatoprotective effect on acute liver injuries induced by CCl(4), and the results suggested that the effect of AFM against CCl(4)-induced liver damage was related to antioxidant properties.     

Antioxidant properties of Asparagus racemosus against damage induced by gamma-radiation in rat liver mitochondria

The possible antioxidant effects of crude extract and a purified aqueous fraction of Asparagus racemosus against membrane damage induced by the free radicals generated during gamma-radiation were examined in rat liver mitochondria. gamma-Radiation, in the dose range of 75-900 Gy, induced lipid peroxidation as assessed by the formation of thiobarbituric acid reactive substances (TBARS) and lipid hydroperoxides (LOOH). Using an effective dose of 450 Gy, antioxidant effects of A. racemosus extract were studied against oxidative damage in terms of protection against lipid peroxidation, protein oxidation, depletion of protein thiols and the levels of the antioxidant enzyme, superoxide dismutase. An active fraction consisting of polysaccharides (termed as P3) was effective even at a low concentration of 10 microg/ml. Both the crude extract as well as the P3 fraction significantly inhibited lipid peroxidation and protein oxidation. The antioxidant effect of P3 fraction was more pronounced against lipid peroxidation, as assessed by TBARS formation, while that of the crude extract was more effective in inhibiting protein oxidation. Both the crude extract and P3 fraction also partly protects against radiation-induced loss of protein thiols and inactivation of superoxide dismutase. The inhibitory effects of these active principles, at the concentration of 10 microg/ml, are comparable to that of the established antioxidants glutathione and ascorbic acid. Hence our results indicate that extracts from A. racemosus have potent antioxidant properties in vitro in mitochondrial membranes of rat liver.     

Evaluation of antioxidant activity of leaf extract of Seabuckthorn (Hippophae rhamnoides L.) on chromium(VI) induced oxidative stress in albino rats

The present study reports the antioxidant activity of Seabuckthorn (Hippophae rhamnoides), family Elaegnaceae, on chromium induced oxidative stress in male albino rats. Oxidative stress was induced in the rats by force-feeding of potassium dichromate equivalent to a dose of 30mg/kg body weight (BW) of chromium(VI) for 30 days. Administration of chromium decreased the body weight and increased organ to body weight ratio significantly. Chromium treatment significantly decreased reduced glutathione (GSH), and increased malondialdehyde (MDA) and creatine phosphokinase (CPK) levels; further it also enhanced glutamate oxaloacetate transferase (GOT) and glutamate pyruvate transferase (GPT) levels in the serum. Different doses of the alcoholic leaf extract of Seabuckthorn were evaluated for the protection against the chromium induced oxidative stress. The results show that the leaf extract at a concentration of 100 and 250mg/kg BW protected the animals from the chromium induced oxidative injury significantly.     

A study on antioxidant, free radical scavenging, anti-inflammatory and hepatoprotective actions of Aegiceras corniculatum (stem) extracts

AIM OF THE STUDY: The present study was conducted to evaluate the antioxidant, anti-inflammatory and hepatoprotective potential of Aegiceras corniculatum Linn. Blanco (Aegicerataceae). METHODS AND RESULTS: The n-hexane, ethyl acetate and methanol extracts, derived from Aegiceras corniculatum stems, scavenged superoxide anions (O2*) and hydroxyl radicals (*OH) in nitro blue tetrazolium reduction and deoxyribose degradation assays, respectively. All the extracts inhibited the process of lipid peroxidation at its initiation step. Additionally, in rat liver microsomes n-hexane and ethyl acetate extracts also caused termination of radical chain reaction supporting their scavenging action towards lipid peroxy radicals (LOO*). Moreover, increased production of O2* in human neutrophils, stimulated by phorbol-12-myristate-13-acetate (PMA) and/or opsonized zymosan were also suppressed (IC50 approximately 3-20 microg/mL). Thereby, revealing the ability of plant extracts to antagonize the oxidative stress via interference with NADPH oxidase metabolic pathway. These in vitro results coincide with the reduction in the glucose oxidase-induced paw edema in mice in the presence of ethyl acetate and methanol extracts (10, 50, and 100mg/kg, i.p.). Plant extracts (250, 500 and 1000 mg/kg, p.o.) also significantly protected the carbon tetrachloride (CCl4)-induced oxidative tissue injury in rat liver. This was reflected by a approximately 60% decline in the levels of serum aminotransferase enzymes. CONCLUSION: Aegiceras corniculatum extracts found to possess pronounced antioxidant effect that may be at least in part related to its anti-inflammatory and hepatoprotective activities. This study provides a scientific basis for the ethnomedical claims that Aegiceras corniculatum is effective against inflammation and liver injury.     

In Vitro effect of D-004, a lipid extract of the ground fruits of the Cuban royal palm (Roystonea regia), on rat microsomal lipid peroxidation

D-004 is a lipid extract of the fruits of the Cuban royal palm (Roystonea regia) containing a mixture of saturated fatty acids. D-004 inhibits prostate hyperplasia (PH) induced with testosterone, in rodents. Since fatty acids inhibit lipid peroxidation (LP), this study investigated whether D-004 prevents in vitro LP. D-004 (0.9-1000 microg/mL) markedly and dose-dependently inhibited in vitro iron-induced LP in native brain and liver microsomes. D-004 showed hydroxyl radical scavenging activity, which could explain partially its antioxidant effect on microsomal iron-induced LP, but it was unable to scavenge superoxide and ABTS radicals, indicating a limited radical scavenging activity. Also, D-004 inhibited CCl4-mediated LP in active liver microsomes through a decreased generation of radical species rather than a radical trapping action on CCl(4)-derived radical species. D-004 also inhibited lipooxygenase (LOX) and cyclooxygenase (COX) activities, and the generation of protein-associated carbonyl groups after LP. Since increased oxidative stress has been linked to PH, the antioxidant effect of D-004 shown here could contribute to explaining its beneficial effects on T-induced PH in rodents. Nevertheless, this study shows only in vitro results. Further studies should investigate whether D-004 also exhibits antioxidant effects in vivo.     

Effects of black tea extract on carbon tetrachloride-induced lipid peroxidation in liver, kidneys, and testes of rats

Previous studies have shown that green tea and black tea have antioxidant effects and chemopreventive activity against chronic disease including some forms of cancer. We have, therefore, examined the effects of an aqueous extract of black tea against carbon tetrachloride-induced lipid peroxidation as determined by the formation of thiobarbituric acid reactive substances in liver, kidneys and testes of rats. A 0.7% black tea extract was used which contained 2 mg of black tea extract solids per mL. Black tea was administered as drinking water for 3, 6, 9 and 12 months before and during carbon tetrachloride (CCl(4)) treatment in female and male rats. Rats were treated with a single oral dose of CCl(4) 1.0 mL/kg. All rats were killed 24 h after CCl(4) treatment. All animals were dosed with CCl(4) at the end of the 3, 6, 9, and 12 month of treatment. Black tea treatment for 75 days produced a decrease in CCl(4)-induced hepatic lipid peroxidation but significant decreases in thiobarbituric acid reactive substances occurred 3 months after treatment in both female and male rats. In liver and kidneys, black tea alone increased lipid peroxidation by 30%-50% in female and male rats. However, black tea decreased CCl(4)-induced lipid peroxidation in liver of female and male rats by approximately 49% and 37%, respectively. Black tea decreased CCl(4)-induced lipid peroxidation in testes by approximately 37% at a dose of 1.0 mL CCl(4)/kg. These results suggest that the protective effects of black tea against CCl(4)-induced lipid peroxidation in liver, kidneys and testes is due at least partly to its antioxidant properties, scavenging CCl(4)-associated free radicals.     

Flavonoids of an extract of Pterospartum tridentatum showing endothelial protection against oxidative injury

Pterospartum tridentatum is a Leguminosae that grows spontaneously in Portugal. The flowers are used in popular medicine for the treatment of throat irritation conditions and in herbal mixtures for diabetes. Diabetic vascular complications are due, among other reasons, to increased oxidative stress and for that reason antioxidants are believed to be beneficial for the diabetic patient. The flower water extract of this herbal drug showed dose-dependent protective effect of cultured human endothelial cells against oxidative injury induced by H2O2, at concentrations > or =0.3 mg/ml. This water extract, after liquid-liquid and chromatographic fractionation afforded one new isoflavone (5,5'-dihydroxy-3'-metoxi-isoflavone-7-O-beta-glucoside) and three other known isoflavones (prunetin, genistin and sissotrin). The structural characterisation of isolated compounds was achieved by UV, NMR and MS analysis. The flavonol glycoside isoquercitrin was also identified in the extract by HPLC analysis. Isoquercitrin is one of the active antioxidant principles of the extract since it showed dose-dependent protective effect against oxidative injury at concentrations > or =0.3 mM. Isoflavones were inactive at the same concentrations. The results suggest that the water extract of this herbal drug may prevent or reduce the development of diabetic vascular complications.     

薤白提取物的抗氧化作用研究

本文研究了薤白乙醚提取物、乙酸乙酯提取物、水提取物、挥发油及原汁对白酒造成的氧应激态大鼠血清超氰化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、过氧化脂质(LPO)和T淋巴细胞百分率的影响。结果表明,薤白原汁对该大鼠的血清SOD、CAT和T淋巴细胞具有明显保护作用且显著抑制血清过氧化脂质形成。但是,低、中剂量(2.4gkg~(-1),4.8gkg~(-1))薤白原汁的作用优于高剂量(8.0gkg~(-1))者。另外,薤白原汁对Fenton反应产生的羟自由基(·OH)有清除作用,该作用与其浓度呈正相关。     

Evaluation of the efficacy of Lawsonia alba in the alleviation of carbon tetrachloride-induced oxidative stress

The hepatoprotective activity of the 50% ethanol extract of the bark of Lawsonia alba syn. L. inermis was investigated against the carbon tetrachloride-induced oxidative stress. Pretreatment of rats with doses of 250 and 500 mg/kg of the plant extract significantly (P < 0.001) lowered serum transaminases (GOT and GPT) and LDH levels, respectively, in a dose dependent manner against the significant (P < 0.001) rise of these damage marker enzymes when challenged with CCl4 (1 ml/kg, orally). Parallel to these changes, the plant extract prevented CCl4-induced oxidative stress by significantly maintaining the levels of reduced glutathione (GSH), its metabolizing enzymes and simultaneously inhibiting the production of free radicals. Pretreatment of rats with the extract also inhibited the peroxidation of microsomal lipids in a dose-dependent manner.     

Antibacterial,antiprotozoal and antioxidant activity of five plants used in Izabal for infectious diseases

Methanol and aqueous extracts from fi ve plant species, used in traditional medicine in Guatemala for the treatment of microbial infections, were tested in vitro for their ability to scavenge DPPH, OH(.) and O(2) (-) radicals and to inhibit lipoperoxidation (LPO) in order to establish a relationship between their antioxidant activities and their effects against infectious agents. Acalypha guatemalensis, Ocimum micranthum and Smilax spinosa possessed a significant activity against both the three free radicals assayed and LPO; Guazuma ulmifolia showed effects against DPPH and OH(.). Piper auritum showed no activity. These extracts were also evaluated for antibacterial and antiprotozoal activities. A. guatemalensis showed activity against Pseudomonas aeruginosa; S. spinosa was active against Salmonella typhi, and A. guatemalensis, and S. spinosa against Trypanosoma cruzi or Leishmania spp.     

The antioxidant activity of standardized extract of Ginkgo biloba (EGb 761) in rats

The standardized extract of Ginkgo biloba (EGb 761) has been widely employed for its significant benefit in neurodegenerative disorders. Although antioxidative actions have been attributed to this extract, the mechanisms of the multiple principles involved in this pharmacological activity are not completely established. Parkinson's and Alzheimer's diseases are frequently associated with oxidative stress and defects in the cellular protective mechanisms. In this study, the lipid peroxidation (LPO) and the activity of the antioxidant enzymes, catalase (CAT) and superoxide dismutase (SOD) were evaluated in the hippocampus, striatum and substantia nigra (SN) of rats treated with EGb 761. An increase in the CAT and SOD activities in the hippocampus, striatum and SN, and a decrease of the LPO in the hippocampus were observed. These data are additional to the antioxidant properties of EGb 761 reported in the literature and indicate a possible role for the extract in the treatment of diseases involving free radicals and oxidative damage.     

Protective activity of Bacopa monniera Linn. on nicotine-induced toxicity in mice

Nicotine, a pharmacologically active component of cigarettes smoke causes devastating effects in important biomolecules of the cell through generation of free radicals leading to genomic instability. Bacopa monniera is a reputed drug in Ayurveda known for its hepatoprotective and DNA protective effects. In this study, an aqueous extract of Bacopa monniera (BAE, 50 mg/kg i.p.) was investigated for its ability to reduce nicotine-induced lipid peroxidation (LPO) and confer genoprotection in Swiss mice. Genoprotective effect was assayed using micronucleus (MN) assay. LPO status was studied by evaluating MDA levels and antioxidant status. Nicotine altered hepatic function as evident by increased ALP and GST levels and decreased SOD, catalase and GPx activities. BAE treatment restored antioxidant enzymes such as SOD, catalase and GPx in liver. BAE treatment also significantly reduced the frequency of micronuclei induced by nicotine by decreasing the incidence of micronucleated polychromatic erythrocytes (MN-PCE). Hepatic GSH, ALP and GST levels were brought to normal values indicating protection. The results of the present study suggest that BAE exerts protective effects by modulating the extent of lipid peroxidation and enhancing the antioxidant status.