Protective Role of Quercetin on Polychlorinated Biphenyls (Aroclor‐1254) Induced Oxidative Stress and Apoptosis in Liver of Adult Male Rats

The present study aims to investigate the protective effect of quercetin against Aroclor‐1254–induced hepatotoxicity in rats. Male Wistar rats were grouped into Group I control received vehicle (corn oil; 1 mL/kg bwt); Group II quercetin alone (50 mg/kg bwt/day orally); Group III Aroclor‐1254 (2 mg/kg bwt/day intraperitoneally); Group IV Aroclor‐1254 + quercetin treated for 30 days. The Aroclor‐1254 treatment caused significant alteration in the biochemical parameters (hydrogen peroxide, lipid peroxidation, reduced glutathione levels, and alkaline phosphatase activity). The expressions of apoptotic and antiapoptotic proteins and the liver histology of Aroclor‐1254–exposed rats showed cytoplasmic degeneration along with infiltration of polymorphonuclear cells. Whereas simultaneous treatment with quercetin normalized all the biochemical parameters, consequently it inhibited apoptosis mediated by Aroclor‐1254 by downregulating aryl hydrocarbon receptor, p53 and apoptotic protein (Bax, caspase‐9, caspase‐3) and upregulating the antiapoptotic protein (Bcl‐2) expression patterns; thereby, quercetin reduces alteration in hepatocellular morphology. Thus quercetin exhibited hepatoprotective effect. © 2012 Wiley Periodicals, Inc. J BiochemMol Toxicol 26:522‐532, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21466     

In vitro and in vivo hepatoprotective activity of Cissampelos pareira against carbon-tetrachloride induced hepatic damage

Administration of hydroalcoholic extract of Cissampelos pareira roots (CPRE) and standard drug silymarin in rats showed significant hepatoprotective action against CCl4 induced hepatotoxicity. Elevated serum marker enzymes of AST, ALT, ALP and serum bilirubin were significantly reduced to near normal level in CPRE treated rats. Lipid peroxidation level was decreased significantly in CPRE 100, 200, 400 mg/kg doses treatment groups. In case of antioxidant enzymes SOD, catalase levels were increased significantly after CPRE 200, 400 mg/kg doses, similarly it increased the enzyme levels of GST, GPx, and GSH. CPRE 200, 400 mg/kg decreased cholesterol level, and increased triglyceride level. In vitro hepatoprotective activity of the extract was evaluated at 20, 40, 60, 80 and 100 microg/ml concentration against CCl4 (1%) induced toxicity in freshly isolated rat hepatocytes. HepG2 cells showed significant dose dependent increase in percentage viability at the doses 20, 40, 60, 80 and 100 microg/ml of CPRE compared to CCl4 exposed HepG2 cells. Results of this study strongly demonstrate Cissampelos pariera having good hepatoprotective potential.     

Hepatoprotective activity of Luffa acutangula against CCl4 and rifampicin induced liver toxicity in rats: a biochemical and histopathological evaluation

Hepatoprotective activity of hydroalcoholic extract of Luffa acutangula (HAELA) against carbon tetrachloride (CCl4) and rifampicin-induced hepatotoxicity in rats was evaluated and probable mechanism(s) of action has been suggested. Administration of standard drug- silymarin and HAELA showed significant hepatoprotection against CCl4 and rifampicin induced hepatotoxicity in rats. Hepatoprotective activity of HAELA was due to the decreased levels of serum marker enzymes viz., (AST, ALT, ALP and LDH) and increased total protein including the improvement in histoarchitecture of liver cells of the treated groups as compared to the control group. HAELA also showed significant decrease in malondialdehyde (MDA) formation, increased activity of non-enzymatic intracellular antioxidant, glutathione and enzymatic antioxidants, catalase and superoxide dismutase. Results of this study demonstrated that endogenous antioxidants and inhibition of lipid peroxidation of membrane contribute to hepatoprotective activity of HAELA.     

Hepatoprotective activity of Cassia fistula leaf extract.

Hepatoprotective activity of the n-heptane extract of Cassia fistula leaves was investigated by inducing hepatotoxicity with paracetamol in rats. The extract at a dose of 400 mg/kg body wt. exhibited orally, significant protective effect by lowering the serum levels of transaminases (SGOT and SGPT), bilirubin and alkaline phosphatase (ALP). The effects produced were comparable to that of a standard hepatoprotective agent.     

Potential hepatoprotective effects of flavonoids contained in propolis from South Sulawesi against chemotherapy agents

The use of doxorubicin and epirubicin as chemotherapy agent causes side effects such as liver damage due to oxidative stress by reactive oxygen species (ROS) that cause increased of ALT and AST level as liver parameter. One source of natural antioxidants as ROS neutralizer comes from flavonoid that contain in propolis. Most researchers claim that flavonoid can be used to protect the liver. The aim of this study was to test the hepatoprotective effect of flavonoid in propolis from South Sulawesi against doxorubicin and epirubicin. The experiment included male Sprague dawley rats divided into nine groups. The rats received the microcapsule propolis or the quercetin orally for 15 days. The hepatotoxicity was promoted by injection epirubicin and doxorubicin (i.v.) with a cumulative dose of 9 mg/kg. In this study, total polyphenol and flavonoid tests of propolis have been carried out, there were 1.1% polyphenols and 2.7% flavonoids, the antioxidant activity tests showed IC50 value of 9849 ppm and LCMS/MS tests supported the presence of phenolic compounds in propolis from South Sulawesi. Liver parameter was measured and the results showed that the propolis 200 mg/kg group produced the lowest ALT and had potential protective effect against doxorubicin and epirubicin-induced hepatotoxicity.     

Protective effect of ursolic acid on ethanol-mediated experimental liver damage in rats

Ursolic acid is a triterpenoid that exists in nature and is the major component of some traditional medicinal herbs. In this study, ursolic acid has been evaluated for its hepatoprotective effect against chronic ethanol-mediated toxicity in rats. Ethanol administration (7.9 g/kg/day) for 60 days resulted in increased oxidative stress, decreased antioxidant defense and liver injury. It also negatively affected the serum total protein, albumin and A/G ratio. Subsequent to the experimental induction of toxicity (i.e. after the initial period of 30 days) ursolic acid treatment performed by co-administering ursolic acid (10, 20 and 40 mg/kg body weight) for 30 days along with the daily dose of ethanol. While this treatment causing a significant improvement in body weight, food intake and serum protein levels, it decreases serum aminotransferase activities (aspartate aminotransferase and alanine aminotransferase) and total bilirubin levels. Ursolic acid improved the antioxidant status of alcoholic rats, which is evaluated by the decreased levels of lipid peroxidation markers in plasma (thiobarbituric acid reactive substances and lipid hydroperoxides) and increased levels of circulatory antioxidants such as reduced glutathione, ascorbic acid and alpha-tocopherol. Histopathological observations were also in correlation with the biochemical parameters. The activity of ursolic acid (20 mg/kg) compares well with silymarin, a known hepatoprotective drug, and seems to be better in certain parameters. The protective effect of ursolic acid is probably related to its antioxidant activities.     

Hepatoprotective action of ethanolic extracts of Melia azedarach Linn. and Piper longum Linn and their combination on CCl4 induced hepatotoxicity in rats

A comparison of analysis in evaluating the hepatoprotective action of ethanolic extract of M. azedarach (MAE) and P. longum (PLE) with their combination biherbal extract (BHE) against carbon tetrachloride (CCl4) induced hepatic damage is reported in albino rats. There was a marked elevation of serum marker enzyme levels in CCl4 treated rats, which were restored towards normalization in the drug (MAE and/or PLE:50 mg/kg body weight po, once daily for 14 days) treated animals. The biochemical parameters like total protein, total bilirubin, total cholesterol, triglycerides, and urea were also restored towards normal levels. The combined BHE showed more significant reduction of the enzymes than MAE or PLE against CCl4 induced hepatotoxicity. The results strongly indicate that BHE has more potent hepatoprotective action than MAE or PLE individually against CCl4 induced hepatic damage in rats. Among these extracts, BHE showed similar hepatoprotective action to silymarin, which was the positive control in this study.     

Protective role of sinapic acid against arsenic: induced toxicity in rats

Arsenic compounds are classified as toxicants and human carcinogens. Environmental exposure to arsenic imposes a big health issue worldwide. Sinapic acid is a phenylpropanoid compound and is found in various herbal materials and high-bran cereals. It has been reported that sinapic acid has antioxidant efficacy as metal chelators due to the orientation of functional groups. However, it has not yet been examined in experimental animals. In light of this fact, the purpose of this study was to characterize the protective role of sinapic acid against arsenic induced toxicity in rats. Rats were orally treated with arsenic alone (5 mg/kg body weight (bw)/day) plus sinapic acid at different doses (10, 20 and 40 mg/kg bw/day) for 30 days. Hepatotoxicity was measured by the increased activities of serum hepatospecific enzymes namely aspartate transaminase, alanine transaminase, alkaline phosphatase, gamma glutamyl transferase, lactate dehydrogenase and total bilirubin along with increased elevation of lipid peroxidative markers, thiobarbituric acid reactive substances, lipid hydroperoxides, protein carbonyl content and conjugated dienes. The toxic effect of arsenic was also indicated by significantly decreased activities of enzymatic antioxidants like superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, glutathione reductase and glucose-6-phosphate dehydrogenase along with non-enzymatic antioxidant like reduced glutathione. Administration of sinapic acid exhibited significant reversal of arsenic induced toxicity in hepatic tissue. The effect at a dose of 40 mg/kg bw/day was more pronounced than the other two doses (10 and 20 mg/kg bw/day). All these changes were supported by reduction of arsenic concentration and histopathological observations of the liver. These results suggest that sinapic acid has a protective effect over arsenic induced toxicity in rat.     

Role of carnosine in preventing thioacetamide-induced liver injury in the rat

Carnosine (beta-alanyl-L-histidine) is a dipeptide with antioxidant properties. Free radicals are involved in the pathogenesis of acute liver injury induced by thioacetamide (TAA). In this study, we investigated the effect of carnosine treatment on TAA-induced oxidative stress and hepatotoxicity. Rats were injected intraperitoneally with TAA (500 mg/kg) and carnosine (250 mg/kg, intraperitoneal) was co-administered with TAA. All animals were killed 24 h after injections. TAA administration resulted in hepatic necrosis, significant increases in plasma transaminase activities as well as hepatic lipid peroxide levels. In addition, hepatic antioxidant system was found to be depressed following TAA administration. When carnosine was co-administered with TAA in rats, plasma transaminase activities were found to approach to normal values in rats. Histological findings also suggested that carnosine has preventive effect on TAA-induced hepatic necrosis. Carnosine treatment caused significant decreases in lipid peroxide levels in TAA-treated rats without any changes in enzymatic and non-enzymatic antioxidants except vitamin E in the liver of rats. Our findings indicate that carnosine, in vivo may have a preventive effect on TAA-induced oxidative stress and hepatotoxicity by acting as an non-enzymatic antioxidant itself.     

Veratric acid ameliorates hyperlipidemia and oxidative stress in Wistar rats fed an atherogenic diet

An investigation was made to reveal the protective effects of veratric acid (VA), a phenolic acid against atherogenic diet-induced hyperlipidemic rats. Male albino Wistar rats were fed with atherogenic diet (4% cholesterol, 1% cholic acid, and 0.5% 2-thiouracil) daily for 30 days and treated with VA (40 mg/kg body weight) daily for a period of 30 days. Rats fed with atherogenic diet showed significant (P < 0.05) elevation in the level of plasma lipids, systolic and diastolic blood pressure, oxidative stress markers (thiobarbituric acid reactive substances, lipid peroxides) and significant (P < 0.05) reduction in the activities of enzymatic (superoxide dismutase, catalase, glutathione peroxidase) and non-enzymatic (vitamin C, vitamin E, and reduced glutathione) antioxidants in erythrocytes, plasma, and tissues (liver, kidney, and aorta). Oral administration of VA (40 mg/kg body weight) for 30 days to atherogenic diet fed rats markedly attenuates systolic, diastolic blood pressure and lipid peroxidation products. Further, VA treatment significantly improved enzymatic and non-enzymatic antioxidants levels and showed beneficial effects on lipid profile in atherogenic diet rats. All the above alterations were supported by histopathological observations. These results indicate that oral administration of VA ameliorates atherogenic diet-induced hyperlipidemia in rats by its free radical scavenging; improving the antioxidants and lipid lowering properties.     

Protective Effects of Pterostilbene against Acetaminophen‐Induced Hepatotoxicity in Rats

The present study was undertaken to evaluate the protective effect of pterostilbene against acetaminophen‐induced hepatotoxicity. Silymarin was used as a standard hepatoprotective agent. A single dose of acetaminophen (800 mg/kg i.p.), injected to male rats, caused significant increases in serum levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, bilirubin, total cholesterol, triglycerides, tumor necrosis factor alpha, and hepatic contents of malondialdehyde, nitric oxide, caspase‐3, hydroxyproline, with significant decreases in serum HDL‐cholesterol, total proteins, albumin, and hepatic activities of reduced glutathione, superoxide dismutase and catalase as compared with the control group. On the other hand, administration of each of pterostilbene (50 mg/kg, p.o.) and silymarin (100 mg/kg, p.o.) for 15 days before acetaminophen ameliorated liver function and oxidative stress parameters. Histopathological evidence confirmed the protection offered by pterostilbene from the tissue damage caused by acetaminophen. In conclusion, pterostilbene possesses multimechanistic hepatoprotective activity that can be attributed to its antioxidant, anti‐inflammatory, and antiapoptotic actions.     

The cardioprotective effects of a combination of quercetin and α-tocopherol on isoproterenol-induced myocardial infarcted rats

The present study aims to evaluate the combined protective effects of quercetin and α-tocopherol on isoproterenol-treated myocardial infarcted rats. Male albino Wistar rats were pretreated with a combination of quercetin (10 mg/kg) and α-tocopherol (10 mg/kg) daily for 14 days. After the pretreatment, rats were injected isoproterenol (100 mg/kg) to induce myocardial infarction. Isoproterenol-treated rats showed increased levels of serum troponins and increased intensities of serum lactate dehydrogenase-1 and -2 isoenzyme bands. Isoproterenol treatment also showed significant decreased levels of antioxidant system and significant increased levels of plasma lipid peroxidation, plasma uric acid, and the heart calcium. Furthermore, isoproterenol-treated rat's electrocardiogram showed elevated ST segments. Combined pretreatment with quercetin and α-tocopherol normalized all the biochemical parameters and minimized the alterations in electrocardiogram. Histopathology of myocardium also confirmed the cardioprotective effects of quercetin and α-tocopherol. In vitro studies confirmed the mechanism of action of quercetin and α-tocopherol. Thus, quercetin and α-tocopherol exhibited cardioprotective effects against isoproterenol-induced cardiotoxicity due to their scavenging free radicals, improving antioxidants and maintaining Ca(2+) levels. Our study also showed that combined pretreatment (quercetin and α-tocopherol) was highly effective than single pretreatment (quercetin or α-tocopherol).     

Hepatoprotective effect of Pergularia daemia (Forsk.) ethanol extract and its fraction

Ethanol extract and its ethanol fraction from aerial parts of P. daemia exhibited significant hepatoprotective effect against CCl4 induced hepatotoxicity in rats. Glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, alkaline phosphatase, total bilirubin, total cholesterol, total protein and albumin in serum indicated hepatoprotective effect of the ethanol extract and its ethanol fraction. Histopathological examination of liver sections confirmed that, pre-treatment with ethanol extract and its ethanol fraction prevented hepatic damage induced by CCl4. The results were comparable with the standard hepatoprotective drug silymarin. The extract and its fraction showed no signs of toxicity up to a dose level of 2000 mg/kg. It is suggested that, the presence of flavonoids in ethanol extract and its ethanol fraction may be responsible for hepatoprotective properties. High Performance Thin Layer Chromatography profile of flavonoids of bio-active extracts was developed using quercetin-3-glucoside as a marker. Results indicate hepatoprotective properties of ethanol extract of P. daemia.     

Lupeol ameliorates aflatoxin B1-induced peroxidative hepatic damage in rats

Aflatoxins are potent hepatotoxic and hepatocarcinogenic agents. Reactive oxygen species and consequent peroxidative damage caused by aflatoxin are considered to be the main mechanisms leading to hepatotoxicity. The present investigation aims at assessing the hepatoprotective effect of lupeol, a pentacyclic triterpene isolated from the stem bark of Crataeva nurvala, on aflatoxin B(1) (AFB(1))-induced hepatotoxicity in a rat model. The hepatoprotection of lupeol is compared with silymarin, a well known standard hepatoprotectant. Lactate dehydrogenase, alkaline phosphatase, alanine and aspartate aminotransferases were found to be significantly increased in the serum and decreased in the liver of AFB(1) administered (1 mg/kg body mass, orally) rats, suggesting hepatic damage. Marked increase in the lipid peroxide levels and a concomitant decrease in the enzymic (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase and glutathione-S-transferase) and nonenzymic (reduced glutathione, vitamin C and vitamin E) antioxidants in the hepatic tissue were observed in AFB(1) administered rats. Pretreatment with lupeol (100 mg/kg body mass, orally) and silymarin (100 mg/kg body mass, orally) for 7 days reverted the condition to near normalcy. Hepatoprotection by lupeol is further substantiated by the normal histologic findings as against degenerative changes in the AFB(1) administered rats. The results of this study indicate that lupeol is a potent hepatoprotectant as silymarin.     

The modulatory influence of p-methoxycinnamic acid, an active rice bran phenolic acid, against 1,2-dimethylhydrazine-induced lipid peroxidation, antioxidant status and aberrant crypt foci in rat colon carcinogenesis

We investigated the chemopreventive effect of p-methoxycinnamic acid (p-MCA), an active phenolic acid of rice bran, turmeric, and Kaemperfia galanga against 1,2-dimethylhydrazine-induced rat colon carcinogenesis. Male albino Wistar rats were randomly divided into six groups. Group 1 consisted of control rats that received a modified pellet diet and 0.1% carboxymethyl cellulose. The rats in Group 2 received a modified pellet diet supplemented with p-MCA [80 mg/kg body weight (b.wt.) post-orally (p.o.)] everyday. The rats in Groups 3-6 received 1,2-dimethylhydrazine (DMH) (20 mg/kg b.wt.) via subcutaneous injections once a week for the first 4 weeks; additionally, the rats in Groups 4, 5 and 6 received p-MCA at doses of 20, 40 and 80 mg/kg b.wt./day p.o., respectively, everyday for 16 weeks. The rats were sacrificed at the end of the experimental period of 16 weeks. The DMH-treated rats exhibited an increased incidence of aberrant crypt foci (ACF) development; an increased crypt multiplicity; decreased concentrations of tissue lipid peroxidation markers such as thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD) and lipid hydroperoxides (LOOH); decreased levels of tissue enzymic antioxidants such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR); and decreased levels of non-enzymic antioxidants such as reduced glutathione (GSH) and vitamins C, E and A in the colon. Supplementation with p-MCA significantly reversed these changes and significantly inhibited the formation of ACF and its multiplicity. Thus, our findings demonstrate that p-MCA exerts a strong chemopreventive activity against 1,2-dimethylhydrazine-induced colon carcinogenesis by virtue of its ability to prevent the alterations in DMH-induced circulatory and tissue oxidative stress and preneoplastic changes. p-MCA was more effective when administered at a dose of 40 mg/kg b.wt. than at the other two doses tested.     

Blepharisides A and B,new flavonol glycosides from Blepharis ciliaris growing in Saudi Arabia

Bio-guided fractionation of the total MeOH extract (TME) of the aerial parts of Blepharis ciliaris (L.) B.L. Burtt. (Acanthaceae) growing in Saudi Arabia was carried out to evaluate its hepatoprotective activity against CCl₄-induced hepatotoxicity in rats. Successive chromatographic separations of the potent hepatoprotective n-BuOH fraction afforded two new flavonol glycosides, blepharisides A (1) and B (2), along with quercetin 3-O-rutinoside (3). Their structures were established by UV, IR, 1D, 2D NMR, and HRESIMS spectral data, in addition to comparison with literature data. Co-treatment of CCl₄ hepatic injured rats with the total MeOH extract (TME) and its fractions significantly restored the hepatic marker enzymes and total bilirubin to near-normal values compared to silymarin (reference drug). The isolated compounds were evaluated for their antioxidant and anti-inflammatory activities. They displayed significant antioxidant activity (DPPH assay) in relation to propyl gallate (positive control) (% inhibition of 88.2, 87.9, and 74.2, respectively). Compounds 1 and 2 demonstrated anti-inflammatory effects in the carrageenin induced paw edema method at a dose of 10 mg/kg.     

Ferulic Acid Modulates Fluoride-Induced Oxidative Hepatotoxicity in Male Wistar Rats

The present study is aimed to evaluate the protective effect of ferulic acid (FA) on fluoride-induced oxidative hepatotoxicity in male Wistar rats. Fluoride (25 mg/L) was given orally to induce hepatotoxicity for 12 weeks. Hepatic damage were assessed using status of pathophysiological markers like serum marker enzymes like aspartate transaminase, alanine transaminase, alkaline phosphatase, acid phosphatase, gamma glutamyl transferase, lactate dehydrogenase, bilirubin, lipid profile, total protein content levels, and histopathological studies. Treatment with FA significantly reduced the degree of histological abberations and rescued lipid peroxidation, as observed from reduced levels of lipid hydroperoxides, nitric oxide, restored levels of enzymic and non-enzymic antioxidants, and total protein content, with a concomitant decline in the levels of marker enzymes and lipid profile in fluoride-induced rats. These results suggest that ferulic acid has the ability to protect fluoride-induced hepatic damage.     

Potential hepatoprotective activity of ononitol monohydrate isolated from Cassia tora L. on carbon tetrachloride induced hepatotoxicity in wistar rats

Ononitol monohydrate, structurally similar to glycoside was isolated from Cassia tora L. leaves. Fifty Male rats were divided into five groups. Group I served as normal control. Group II, III and IV rats were induced hepatotoxicity by CCl₄ administering single dose of CCl₄ on 8th day only. Group III was treated with ononitol monohydrate (20 mg/kg body weight) and group IV was treated with reference drug silymarin (20 mg/kg body weight) both dissolved in corn oil and administering for 8 days. Ononitol monohydrate with corn oil alone was given for 8 days (group V). At the end of the experimental period all the animals were sacrificed and analyzed for biochemical parameters to assess the effect of ononitol monohydrate treatment in CCl₄ induced hepatotoxicity. In in vivo study, ononitol monohydrate decreased the levels of serum transaminase, lipid peroxidation and TNF-α but increased the levels of antioxidant and hepatic glutathione enzyme activities. Compared with reference drug silymarin ononitol monohydrate possessesed high hepatoprotective activity. Histopathological results also suggested the hepatoprotective activity of ononitol monohydrate with no adverse effect. Hence we conclude that ononitol monohydrate is a potent hepatoprotective agent.     

Studies on the protective effects of caffeic acid and quercetin on chemical-induced hepatotoxicity in rodents.

Caffeic acid and quercetin, the well-known phenolic compounds widely present in the plant kingdom, were investigated for their possible protective effects against paracetamol and CCl4-induced hepatic damage. Paracetamol at the oral dose of 1 g/kg produced 100% mortality in mice while pretreatment of separate groups of animals with caffeic acid (6 mg/kg) and quercetin (10 mg/kg) reduced the death rate to 20% and 30%, respectively. Oral administration of sub-lethal dose of paracetamol (640 mg/kg) produced liver damage in rats as manifested by the significant (P<0.01) rise in serum levels of aminotransferases (aspartate transaminase (AST) and alanine transaminase (ALT)) compared to respective control values. The serum enzyme values were significantly (P<0.01) lowered on pretreatment of rats with either caffeic acid (6 mg/kg) or quercetin (10 mg/kg). Similarly, the hepatotoxic dose of CCl4 (1.5 ml/kg; orally) also raised significantly (P<0.05) the serum AST and ALT levels as compared to control values. The same dose of the caffeic acid and quercetin was able to prevent CCl4-induced rise in serum enzymes. Caffeic acid and quercetin also prevented the CCl4-induced prolongation in pentobarbital sleeping time confirming their hepatoprotectivity. These results indicate that caffeic acid and quercetin exhibited hepatoprotective activity possibly through multiple mechanisms.