Liver Tissue Malondialdehyde Research Articles

Anti-inflammatory and antioxidative effects of the methanolic extract of the aerial parts of Mitracarpus frigidus in established animal models

This study reports the in vivo anti-inflammatory and antioxidative effects of the methanolic extract of the aerial parts of Mitracarpus frigidus (MFM) and its chemical fingerprint. The acute anti-inflammatory activity was performed using the carrageenan-induced paw oedema and peritonitis, ear oedema induced by croton oil and ethyl phenylpropiolate methods. Total COX, COX-1 and COX-2 expression was also evaluated. Chronic activity was determined by cotton pellet granuloma model. The antioxidative activity was assessed using liver tissue malondialdehyde, catalase and myeloperoxidase activities. M. frigidus showed an intense acute anti-inflammatory action (100 and 300 mg/kg) in a nondose-dependent manner with selective inhibition of COX-2 expression. This activity may be also related to the strong antioxidative effect observed. By the other side, the chronic anti-inflammatory activity of MFM was not expressive. Kaempferol, kaempferol-O-rutenoside, rutin, ursolic acid and psychorubrin were identified in MFM. The anti-inflammatory activity of MFM was probably due to inhibition of COX expression in a selective manner for COX-2. Other mechanisms, such as inhibition of inflammatory mediators and of the oxidative stress were possibly involved in the effects observed. To the best of our knowledge, it is the first time those activities are reported for M. frigidus.

Effect of ghrelin on chronic liver injury and fibrogenesis in male rats: Possible role of nitric oxide

Recent studies have revealed that ghrelin may be an antioxidant and anti-inflammatory agent in many organs, however its role in chronic liver injury (CLI) remains unclear. The role of nitric oxide (NO) in CLI is controversial as evidence suggests that NO is either a primary mediator of liver cell injury or exhibits a protective effect against injurious stimuli. Recent evidence demonstrated that the therapeutic potential for ghrelin was through eNOS activation and increase in NO production. However, its role on NO production in the liver has not been previously investigated. The aim of this study was to investigate the role of ghrelin in treatment of CLI, and whether this action is mediated through NO. Forty male rats were divided into four groups: Group I: Control; Group II: chronic liver injury (CLI); Group III: CLI+Ghrelin; and Group IV: CLI+Ghrelin+l-NAME. Liver enzymes and tumor necrosis factor alpha (TNF-α), were measured to assess hepatocellular injury. Liver tissue collagen content, malondialdehyde (MDA), gene expression of Bax, Bcl-2, and eNOS were assessed to determine the mechanism of ghrelin action. Results showed that ghrelin decreased serum liver enzymes and TNF-α levels. Ghrelin also reduced liver tissue collagen, MDA, and Bax gene expression, and increased Bcl-2 and eNOS gene expression. The effects on TNF-α, collagen, MDA, Bax, and eNOS were partially reversed in Group IV, suggesting that ghrelin's action could be through modulation of NO levels. Therefore, ghrelin's hepatoprotective effect is partially mediated by NO release.

In case of obesity, longevity-related mechanisms lead to anti-inflammation

The exact mechanisms which contribute to longevity have not been figured out yet. Our aim was to find out a common way for prompting longevity by bringing together the well-known applications such as food restriction, exercise, and probiotic supplementing in an experimental obesity model. Experimental obesity was promoted in a total of 32 young (2months old) and 32 aged (16months old) male Wistar albino rats through 8-week cafeteria diet (salami, chocolate, chips, and biscuits). Old and young animals were divided into groups each consisting of eight animals and also divided into four subgroups as obese control, obese food restriction, obese probiotic-fed and obese exercise groups. Probiotic group diet contained 0.05%w/total diet inactive and lyophilized Lactobacillus casei str. Shirota. The exercise group was subjected to treadmill running 1h/day, at 21m/min and at an uphill incline of 15% for 5days a week. Food restriction group was formed by giving 40% less food than the others. The control group was fed regular pellet feed ad libitum. This program was continued for 16weeks. Blood samples from all the groups were analyzed for fasting glucose, insulin, IGF-1, insulin-like growth factor binding protein 3 (IGFBP-3), interleukin (IL)-6, IL-12, malondialdehyde (MDA), fT3, TT3, fT4, TT4, and liver tissue MDA levels were measured. All applications showed anti-inflammatory effects through the observed changes in the levels of IGFBP-3, IL-6, and IL-12 in the young and old obese rats. While the interventions normally contribute to longevity by recruiting different action mechanisms, anti-inflammatory effect is the only mode of action for all the applications in the obesity model.

Effect of low dose gamma rays on certain essential metals and oxidative stress in different rat organs

The present work aimed to determine the effect of low dose (0.03 Gy) γ-rays on certain essential metals namely Fe, Cu, Zn and Ca levels in various tissues (liver, kidney, testis, spleen, intestine, heart and brain) in rats. Also, lipid peroxidation as malondialdehyde (MDA) and metallothionein (MT) levels were measured in liver, kidney and testis. Rats were exposed to total dose of 0.03 Gy γ-rays along 12 h at a low dose rate (2.5 mGy/h). The results obtained manifested elevation in all essential metals studied in liver. All organs showed elevated Ca levels except that of brain with non-significant change in intestine. Decrease in Fe levels were observed in kidney, testis, intestine, heart and brain tissues with insignificant change in spleen tissue. Elevation in MDA in liver and kidney tissues was recorded and an inhibition in MT in liver, kidney and testis tissues was demonstrated. In conclusion, the previous essential metals tested are very sensitive to low dose (0.03 Gy) γ-rays. Such dose can induce alterations in the oxidative stress parameters under investigation.

Potential role of catalase in mice with lipopolysaccharide/D‐galactosamine‐induced fulminant liver injury

Lipopolysaccharide (LPS)-induced liver injury in D-galactosamine (D-Gal)-sensitized mice is a well-established animal model widely used in exploring the pathogenesis of fulminant hepatitis. Increasing evidence has indicated that reactive oxygen species (ROS)-induced oxidative injury may be involved in LPS/D-Gal-induced hepatitis. Catalase (CAT) is a major antioxidant enzyme while aminotriazole (ATZ) is commonly used as a CAT inhibitor. In the present study, the effects of ATZ on LPS/D-Gal-induced liver injury were investigated. Fuliminant liver injury was induced by intraperitoneal injection of LPS combined with D-Gal, ATZ was administrated 0.5 h prior to LPS/D-Gal challenge. The degree of liver injury, the level of hepatic oxidative stress, the grade of hepatic apoptosis and the survival of experimental animals were determined. Our experimental data showed that treatment with ATZ significantly enhanced LPS/D-Gal-induced elevation of serum aspartate transaminase (AST) and alanine transaminase (ALT), exacerbated the hepatic histopathological abnormality and decreased the survival rate of experimental animals. ATZ inhibited the activity of CAT, increased the content of H2 O2 and the levels of malondialdehyde (MDA) in liver tissues. In addition, treatment with ATZ also enhanced LPS/D-Gal-induced hepatic apoptosis as evidenced by increased caspases activities in liver tissues and increased number of terminal deoxynucleotidyl transferase dUTP nick end labeling positive cells in liver sections. These findings suggested that CAT might be involved in the progression of LPS/D-Gal-induced fulminant liver injury.

Effects of dietary selenium of organic form against lead toxicity on the antioxidant system in Cyprinus carpio

In this study was evaluated potential protective effect of organic selenium (Se) on heavy metal stress induced by lead (Pb) in Cyprinus carpio. For this reason, C. carpio was exposed to sublethal concentration of Pb (1.5 mg/L Pb(NO3)2) for 14 days. The fish were fed a basal (control; measured 0.55 mg/kg Se) diet or a basal diet supplemented with 2.50 mg/kg (measured 2.92 mg/kg Se) organic Se (Sel-Plex(®)) during the experiment period. The variations in glutathione peroxidase (GSH-Px), glutathione S-transferase (GST) activities, and levels of reduced glutathione (GSH) with malondialdehyde (MDA) in liver and brain tissues of C. carpio were investigated in experimental groups. GSH levels in liver and brain tissues were significantly decreased by exposure to Pb. GST activity was significantly increased (p < 0.05) in liver tissue, but decreased in brain of treated fish by exposure to Pb. Also, GSH-Px activity was significantly increased in liver tissue, but decreased in brain of Pb-treated fish. Levels of MDA were increased in liver and brain of Pb-treated fish. The organic Se treatment for Pb-intoxicated animals improved activities of GSH-Px, GST and levels of MDA within normal limits. Supplemented Se could be able to improve Pb-induced oxidative stress by decreasing lipid peroxidation and regulating antioxidant defense system in tissues.

Effects of Organic Apricot on Liver Regeneration After Partial Hepatectomy in Rats

BackgroundThe present study investigated the effects of (sun-dried organic apricot/SDOA) supplementation in chow on liver regeneration after partial hepatectomy/(PH) in rats. MethodIn this study, 28 female rats were randomized into four groups. On the 7th day of the study, group 1 underwent laparoscopic intervention while a PH was performed on the other three cohorts. On day 28, all rats were humanely killed. Blood and liver tissue samples were subjected to biochemical determinations, histological examinations, and measurement of tissue oxidative stress enzyme activity. ResultsSerum levels of alanine transaminase (ALT), alkaline phosphatase (ALP), and liver tissue glutathione (GSH) activities were affected by PH and/or SDOA consumption (P < .05). Moderately staining cell counts in group 4 were significantly different from the other three groups (P < .05). However, no significant differences were detected among all groups in regard to aspartate aminotransferase (AST) serum levels or liver tissue superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT) or glutathione peroxidase (GSHpx) activities (P < .05). ConclusionThe 5% SDOA supplementation over a 21-day feeding period showed a beneficial effect on liver regeneration in rats, as reflects by Ki-67 finding although there was no change in ALT or ALP or in liver tissue GSH activity.

The Diagnostic Value of Serum Ischemia-modified Albumin Levels in Experimentally Induced Carbon Monoxide Poisoning and Their Correlation With Poisoning Severity

The objectives were to determine the diagnostic value of blood ischemia-modified albumin (IMA) levels in experimentally induced carbon monoxide (CO) poisoning and to analyze their correlation with poisoning severity. Thirty-six female rats were randomly assigned to one of three groups: I (control group), II (low-dose CO poisoning group), and III (high-dose CO poisoning group). The control group was kept in room air, while groups II and III were exposed to 3 L/min of 3,000 ppm and 3 L/min of 5,000 ppm CO gas for 30 minutes, respectively. Serum carboxyhemoglobin (COHb), IMA, and malondialdehyde (MDA) levels; brain, heart, lung, liver, and kidney tissue MDA measurements; and histopathologic damage scores were then compared. IMA levels were significantly higher in groups II and III than in group I. A moderate positive correlation was observed between COHb and IMA levels. There was a strong positive correlation between COHb levels and degree of damage in all organs, but IMA and MDA levels did not reflect a similar correlation. Ischemia-modified albumin levels are higher in rats exposed to CO. This indicates that IMA levels can potentially be important in the diagnosis of exposure to CO or of CO poisoning. However, IMA levels are not a good biochemical marker in terms of determining the severity of poisoning.

The Ameliorative Effects of L-2-Oxothiazolidine-4-Carboxylate on Acetaminophen-Induced Hepatotoxicity in Mice

The aim of the study was to investigate the ameliorative effects and the mechanism of action of l-2-oxothiazolidine-4-carboxylate (OTC) on acetaminophen (APAP)-induced hepatotoxicity in mice. Mice were randomly divided into six groups: normal control group, APAP only treated group, APAP + 25 mg/kg OTC, APAP + 50 mg/kg OTC, APAP + 100 mg/kg OTC, and APAP + 100 mg/kg N-acetylcysteine (NAC) as a reference control group. OTC treatment significantly reduced serum alanine aminotransferase and aspartate aminotransferase levels in a dose dependent manner. OTC treatment was markedly increased glutathione (GSH) production and glutathione peroxidase (GSH-px) activity in a dose dependent manner. The contents of malondialdehyde and 4-hydroxynonenal in liver tissues were significantly decreased by administration of OTC and the inhibitory effect of OTC was similar to that of NAC. Moreover, OTC treatment on APAP-induced hepatotoxicity significantly reduced the formation of nitrotyrosin and terminal deoxynucleotidyl transferase dUTP nick end labeling positive areas of liver tissues in a dose dependent manner. Furthermore, the activity of caspase-3 in liver tissues was reduced by administration of OTC in a dose dependent manner. The ameliorative effects of OTC on APAP-induced liver damage in mice was similar to that of NAC. These results suggest that OTC has ameliorative effects on APAP-induced hepatotoxicity in mice through anti-oxidative stress and anti-apoptotic processes.

Evaluation of antioxidant and anti-fatigue properties of Trigonella foenum-graecum L. in rats subjected to weight loaded forced swim test

BackgroundTrigonella foenum-graecum L. (Fabaceae) is commonly known as fenugreek. Aim of the present study was to assess anti fatigue potential of fenugreek hydro-alcoholic extract (FHE). MethodsThe anti fatigue activity of FHE was investigated in in vivo rat model subjected to weight loaded forced swim test (WFST) at a dosage of 10 mg/kg body weight. In vitro antioxidant activities were carried out by spectrophotometric methods. ResultsExhaustive swimming time in WFST was increased by more than 2-fold in FHE supplemented group to that of control group on day 13. The FHE treatment lowered malondialdehyde and lactic acid levels in liver and muscle tissues compared with control exercised group (p < 0.05). FHE also reduced serum lactic acid, blood urea nitrogen and creatine phosphokinase activities significantly to that of control. Administration of FHE significantly protected the depletion of serum glucose, liver and muscle glycogen, and activities of antioxidant enzymes i.e. SOD, CAT and GPx (6.05 ± 0.5; 22.0 ± 1.1 and 2084 ± 158 U/mg protein, respectively). ConclusionIn the present study we report that FHE ameliorates various impairments associated with physical fatigue.

Melatonin attenuates high fat diet-induced fatty liver disease in rats

To investigate melatonin's preventive action in oxidative stress in a rat model with high fat diet-induced non-alcoholic fatty liver disease (NAFLD). NAFLD was induced by high fat diet (HFD) in adult, male, Wistar rats, weighing 180-230 g. After acclimatization for one week, they were randomly assigned to 6 experimental groups that comprised animals on regular diet plus 5 or 10 mg/kg melatonin, for 4 or 8 wk; animals on HFD, with or without 5 or 10 mg/kg melatonin, for 4 or 8 wk; and animals on HFD for 8 or 12 wk, with melatonin 10 mg/kg for the last 4 wk. Liver damage was assessed biochemically by the serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and histologically. Lipid peroxidation and oxidative stress were assessed by malondialdehyde and glutathione levels in liver tissue. Lipidemic indices and portal vein pressure were also measured. Compared to rats not receiving melatonin, rats on 5 or 10 mg/kg of melatonin had lower mean liver weight (-5.0 g and -4.9 g) (P < 0.001) and lower liver weight to body weight ratio (-1.0%) (P < 0.001), for the two doses, respectively. All rats fed HFD without melatonin developed severe, grade III, steatosis. Rats on HFD with concurrent use of melatonin showed significantly less steatosis, with grade III steatosis observed in 1 of 29 (3.4%) rats on 10 mg/kg melatonin and in 3 of 27 (11.1%) rats on 5 mg/kg melatonin. Melatonin was ineffective in reversing established steatosis. Melatonin also had no effect on any of the common lipidemic serum markers, the levels of which did not differ significantly among the rats on HFD, irrespective of the use or not of melatonin. Liver cell necrosis was significantly less in rats on HFD receiving melatonin than in those not on melatonin, with the AST levels declining by a mean of 170 U/L (P = 0.01) and 224 U/L (P = 0.001), and the ALT levels declining by a mean of 62.9 U/L (P = 0.01) and 93.4 U/L (P < 0.001), for the 5 and 10 mg/kg melatonin dose, respectively. Melatonin mitigated liver damage due to peroxidation and oxidative stress in liver tissue as indicated by a significant decline in MDA production by 12.7 (P < 0.001) and 12.2 (P < 0.001) μmol/L /mg protein /mg tissue, and a significant increase in glutathione by 20.1 (P = 0.004) and 29.2 (P < 0.001) μmol/L /mg protein /mg tissue, for the 5 and 10 mg/kg melatonin dose, respectively. Melatonin can attenuate oxidative stress, lessen liver damage, and improve liver histology in rats with high fat diet-induced NAFLD, when given concurrently with the diet.

Influence of Silymarin on Valproic Acid Induced Hepatotoxicity in Adult Male Albino Rats

Introduction: Valproic acid (VPA) is a widely prescribed antiepileptic drug, which might induce serious hepatic disorders . Silymarin is currently used as a supportive therapy of liver disorders. Aim of the study: In this study we evaluated the protective effects of silymarin on valproic acid induced hepatotoxicity . Material and Methods: seventy adult male albino rats were divided into 7 groups (10 each), (Ia) negative control, (Ib) positive control, (II) silymarin group, received17.5 mg/kg. (IIIa) low dose VAP group, received 200mg/kg , (IIIb) high dose VAP group received 400 mg/kg (IVa) low dose VPA + silymarin group and (IVb) high dose VPA + silymarin group received doses as previously mentioned. The drugs were gavaged once daily, 6 days/week for 8 weeks, at the end of the experiment rats were sacrificed and estimation of alanine aminotransferase (ALT) and alkaline phosphatase (ALP) in the blood, malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) in liver tissues and histopathological and immunnohistochemical examination of liver tissues were carried out. Results: this study showed significant increase in serum ALT, ALP and hepatic MDA contents while GSH-Px activity significantly reduced (especially in high dose VPA group) when compared with the control. Histopathological changes showed patchy microvesicular steatosis, focal necrosis of hepatocytes, dilated congested central vein and sinusoids. Immunolocalization of Bcl-2 revealed dose dependent weak cytoplasmic staining in the hepatocytes surrounding the central vein. VPA+ Silymarin groups showed partial improvement. Conclusion: It concluded that VPA has dose dependent toxic effects on liver that might be ameliorated by concomitant use of silymarin.

Effect of Ginger Extract on Liver Damage in Experimental Obstructive Jaundice Produced by Main Bile Duct Ligation

Background : Obstructive jaundice is one of the most important surgical causes of childhood jaundices. The aim of this study is to investigate effects of ginger (Gingiber officinalis) extracts on liver damage in experimental obstructive jaundice produced by main bile duct ligation.Materials and Methods : Forty two Wistar-albino rats were randomly allocated into 7 groups (n = 6). Nothing was performed in the control (C) group. Only laparatomy was performed in the sham (Sh) group. The ginger 1 and 2 (Gi and G2) groups received only 100 and 200 mg/kg/day doses of ginger extract for 1 week orally. In study group, common bile duct ligation was done. In treatment 1 and 2 (T and T2) groups common bile duct ligation was followed by administration of 100 and 200 mg/kg/day doses of ginger extract for 1 week orally from the third post operative day, respectively. Blood samples and liver were harvested in order to evaluate the serum aspartate aminotransferase (AST), alanine amino transferase (ALT), gama glutamyltransferase (GGT), total bilirubin (bil), superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA) and liver tissue SOD, GSH, MDA levels and liver apoptosis. Results were analyzed by Mann-Whitney U test statistically.Results : Ginger administration did not result in any differences of serum or tissue levels of the studied parameters and liver apoptosis between the groups statistically (except AST levels in group T2). Tissue GSH and serum SOD levels were only mildly increased in groups receiving ginger alone.Conclusions : There is no evidence for protective, inhibitive and decreasing effects of ginger extract on liver injury in experimental obstructive jaundice with these findings.

Inhalation of hydrogen gas reduces liver injury during major hepatotectomy in swine.

To study the effect of H2 gas on liver injury in massive hepatectomy using the intermittent Pringle maneuver in swine. Male Bama pigs (n = 14) treated with ketamine hydrochloride and Sumianxin II as induction drugs followed by inhalation anesthesia with 2% isoflurane, underwent 70% hepatotectomy with loss of bleeding less than 50 mL, and with hepatic pedicle occlusion for 20 min, were divided into two groups: Hydrogen-group (n = 7), the pigs with inhalation of 2% hydrogen by the tracheal intubation during major hepatotectomy; contrast-group (n = 7), underwent 70% hepatotectomy without inhalation of hydrogen. Hemodynamic changes and plasma concentrations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), hyaluronic acid (HA), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and malondialdehyde (MDA) in liver tissue were measured at pre-operation, post-hepatotectomy (PH) 1 h and 3 h. The apoptosis and proliferating cell nuclear antigen (PCNA) expression in liver remnant were evaluated at PH 3 h. Then we compared the two groups by these marks to evaluate the effect of the hydrogen in the liver injury during major hepatotectomy with the Pringle Maneuver in the swine. There were no significant differences in body weight, blood loss and removal liver weight between the two groups. There was no significant difference in changes of portal vein pressure between two groups at pre-operation, PH 30 min, but in hydrogen gas treated-group it slightly decrease and lower than its in contrast-group at PH 3 h, although there were no significant difference (P = 0.655). ALT and AST in Hydrogen-group was significantly lower comparing to contrast-group (P = 0.036, P = 0.011, vs. P = 0.032, P = 0.013) at PH 1 h and 3 h, although the two groups all increased. The MDA level increased between the two group at PH 1 h and 3 h. In the hydrogen gas treated-group, the MDA level was not significantly significant at pre-operation and significantly low at PH 1 h and 3 h comparing to Contrast-group (P = 0.0005, P = 0.0004). In Hydrogen-group, the HA level was also significantly low to contrast-group (P = 0.0005, P = 0.0005) although the two groups all increased at PH 1 h and 3 h. The expression of cluster of differentiation molecule 31 molecules Hydrogen-group was low to Contrast-group. However, PCNA index (%) was not statistically significant between the two groups (P = 0.802). Microphotometric evaluation of apoptotic index (AI) in terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling-stained tissue after hepatotectomy for 3h, the AI% level in the hydrogen was significantly low to contrast-group (P = 0.012). There were no significant difference between Hydrogen-group and contrast-group at pre-operation (P = 0.653, P = 0.423), but after massive hepatotectomy, the TNF-α and IL-6 levels increase, and its in Hydrogen-group was significantly low compared with contrast-group (P = 0.022, P = 0.013, vs. P = 0.016, P = 0.012), respectively. Hydrogen-gas inhalation reduce levels of these markers and relieved morphological liver injury and apoptosis. H2 gas attenuates markedly ischemia and portal hyperperfusion injury in pigs with massive hepatotectomy, possibly by the reduction of inflammation and oxidative stress, maybe a potential agent for treatment in clinic.

Caffeic acid protects tissue antioxidants and DNA content in methamphetamine induced tissue toxicity in Sprague Dawley rats

Caffeic acid (CA) (3,4-dihydroxycinnamic acid) is among the major hydroxycinnamic acids. Hydroxycinnamic acid is the major subgroup of phenolic compounds. Methamphetamine (METH) is a potent addictive psychostimulant. Chronic use and acute METH intoxication can cause substantial medical consequences, including spleen, kidney, liver and heart. The objective of the present study was to evaluate the antioxidant activity of CA to protect against oxidative stress and DNA damage to various organs in METH toxicity. Thirty-two male Sprague Dawley (SD) rats were divided into four equal groups: group 1 was injected (i.p) with saline (1 mL/kg) while groups 2,3 and 4 were injected (i.p) with METH (10 mg/kg) twice a day over five days period. Where 100 & 200 mg/kg of CA were injected (i.p) into groups 3 and 4, respectively one day before exposure to METH injections. Tissue antioxidants and DNA content were evaluated in different tissues. METH decreased glutathione (GSH) and glutathione peroxidase (GPx) levels while increased malondialdehyde (MDA), catalase (CAT) and protein carbonyl levels in brain (hypothalamus), liver, and kidney tissues of rats. METH increased hyperdiploidy in these tissues and DNA damage results. Prior treatment of CA to animals exposed to METH restores the above parameters to the normal levels and preserves the DNA content of these tissues. These results were supported by histopathological investigations. In conclusion, METH induced oxidative stress and DNA damage and pretreatment of CA before METH injections prevented tissue oxidative stress and DNA damage in METH-treated animals.

Effect of magnesium isoglycyrrhizinate on PLA2 during liver tissue injury following limb ischemia/reperfusion in rats

To investigate the effects of magnesium isoglycyrrhizinate (MI) on the changes of phospholipase A2 (PLA2) induced during liver tissue injury following limb ischemia/reperfusion (I/R) in rats. Twenty-four healthy male Sprague-Dawley rats weighing (230+/-30) g were randomly divided into three groups (n = 8 each) as follows: control (Group C: anesthetization without any ischemia); I/R injury (Group I/R: 4 h ischemia induced by rubber band ligation of the left hind limb around the roots of the hind limb, followed by 6 h of reperfusion, with 1 mL normal saline given via tail vein prior to reperfusion); MI-treated group (Group MI: underwent ischemia and reperfusion, with 1 mL MI (30 mg/kg) infused prior to reperfusion). Levels of TNFa and PLA2 in plasma and liver tissue were measured by enzyme-linked immunosorbent assay (ELISA). Levels of plasma alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine kinase (CK), myeloperoxidase (MPO), and malondialdehyde (MDA), and activities of MPO and MDA in liver tissue were measured by colorimetry. Ultrastructural changes of liver tissue were observed by electron microscopy. The MI group had significantly lower PLA2 and TNFa in liver homogenates and serum than the I/R group (both P less than 0.05). Serum ALT, AST, LDH, and CK were significantly lower in the MI group than in the I/R group (all P less than 0.05), as were the levels of MPO and MDA in liver homogenates and serum (all P less than 0.05). The I/R group showed significantly more liver tissue damage, which appeared to be attenuated in the MI group. MI treatment can inhibit the I/R-induced TNFa, PLA2, and MDA in plasma and liver tissue, as well as decrease the I/R-induced MPO activity in rats. Thus, MI may have protective effects against liver tissue injury following limb ischemia/reperfusion.

Aminotriazole attenuated carbon tetrachloride-induced oxidative liver injury in mice

Carbon tetrachloride (CCl4) has been used extensively to study xenobiotic-induced oxidative liver injury. Catalase (CAT) is a major antioxidant enzyme while aminotriazole (ATZ) is commonly used as a CAT inhibitor. In the present study, the effects of ATZ on CCl4-induced liver injury were investigated. Our experimental data showed that pretreatment with ATZ significantly decreased CCl4-induced elevation of serum aspartate transaminase (AST) and alanine transaminase (ALT) and improved hepatic histopathological abnormality. ATZ dose-dependently inhibited the activity of CAT, but it reduced the content of H2O2 and the levels of malondialdehyde (MDA) in liver tissues. ATZ decreased plasma level of pro-inflammatory cytokines (TNF-α and IL-6) and reduced hepatic levels of myeloperoxidase (MPO). In addition, posttreatment with ATZ also decreased the level of ALT and AST. These data indicated that ATZ effectively alleviated CCl4-induced oxidative liver damage. These findings suggested that ATZ might have potential value in preventing oxidative liver injury.

Protective effects of Plantago asiatica L. extract against ferric‐nitrilotriacetate (Fe‐NTA) induced liver oxidative stress in Wistar rats

The Plantago asiatica L.(PA), a native plant in East Asia (Korea, Japan and China etc.), traditionally used as a popular folk for the treatment of liver diseases. The purpose of this study was to evaluate the liver protective effects of PA extract(PAE) on the Ferric‐nitrilotriacetate(Fe‐NTA)‐induced oxidative hepatotoxicity. Fe‐NTA is a potent hepatotoxic agent and has been reported to induce hepatocyte necrosis. The study of liver protection effect that pretreatment with PAE(1, 2, 4 g/kg b.w.) by gavage to Wistar rats for 7 days before a single dose of Fe‐NTA(13.5 mg Fe/kg b.w., i.p.). Only Fe‐NTA treated group showed significantly increased the serum levels of the hepatic enzyme, aspartate aminotransferase(AST) and alanine aminotransferase(ALT) which is representative liver damage marker, and liver tissue malondialdehyde(MDA), product of lipid peroxidation. Moreover, the level of biomarkers indicate the antioxidants status, glutathione(GSH), glutathione‐S‐transferase(GST), glutathione reductase(GR) and superoxide dismutase(SOD) in liver tissue were decreased. However, PAE pre‐treated group showed decreases in the levels of serum AST and ALT and liver tissue MDA in concentration dependent manner and increases in the level of GSH, GST, GR and SOD. These results are significantly different(p&lt;0.05) to compare with only Fe‐NTA treated group. Thus, our study suggested that PAE might contribute to the chemopreventive material against Fe‐NTA‐mediated liver oxidative damage.

Immobilization stress-induced oxidative damage and its amelioration with green and black teas

Stress is a state of vulnerable cellular homeostasis, which results in free radical generations and subsequent oxidative damage. The aim of this study is to evaluate the effect of green and black teas on immobilization stress-induced oxidative damage in male Wistar albino rats. Six weeks of repeated immobilization for 4 h daily for five consecutive working days per week was applied. Green or black teas were administrated continuously for six weeks in drinking bottles. Enzymatic activities and lipid profile were measured in serum. Liver enzymes and glucose levels were significantly increased by the green tea showed hypoglycemic and antilipidemic effect against stress induced changes. In liver and brain tissues glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD), nucleic acids and total protein levels were estimated. Repeated immobilization stress significantly enhanced the lipid peroxidation in both the tissues. The present results revealed that, the green tea have more protective effect than black tea against stress particularly in brain as compared to liver. It concludes that the antioxidative affect of green tea over the immobilization-induced stress may attribute the rich flavonoids presence in green tea than black tea. Key words: Restraint stress, glutathione, oxidative stress, malondialdehyde, superoxide dismutase.

Effects of the mixture of Swertia pseudochinensis Hara and Silybum marianum Gaertn extracts on CCl4-induced liver injury in rats with non-alcoholic fatty liver disease

To study the mechanism of liver injury induced by carbon tetrachloride (CCl(4)) in rats with non-alcoholic fatty liver disease (NAFLD), and the therapeutic effects of the extract mixture of Dangyao (Swertia pseudochinensis Hara) and Shuifeiji (Silybum marianum Gaertn) on NAFLD rats with liver injury. Male Wistar rats were randomized into normal control group, CCl(4) group, high-fat diet group, high-fat diet plus CCl(4) injection group (model group), diammonium glycyrrhizinate group and extract mixture group. Except the normal control and CCl(4) groups, rats were fed with high-fat diet (88% normal chow, 10% lard and 2% cholesterol) to induce NAFLD. Diammonium glycyrrhizinate and extracts were given by gavage. After eight weeks, a nonlethal dose of CCl(4) was injected intraperitoneally to all rats except the normal and high-fat diet groups. And 48 h later, all rats were sacrificed, and serum and liver tissues were collected for further study. Paraffin-processed liver tissue was stained with hematoxylin-eosin (HE) to observe the pathological changes. Serum alamine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured. The levels of triacylglycerol (TAG), malondialdehyde (MDA) and glutathione (GSH) in liver tissues were also examined. Expression of uncoupling protein 2 (UCP2) was determined by reverse transcription-polymerase chain reaction and Western blotting. Liver sections stained with HE showed that the histopathological changes in the normal control group and the CCl(4) group were mild; massive hepatosteatosis diffusing in lobules was shown in the high-fat diet groups; steatosis, hepatocellular ballooning degeneration and inflammatory infiltration were severe around the central vein in sections of the model group. Compared with the model group, hepatosteatosis and ballooning were significantly attenuated in the treatment groups. Levels of serum ALT and AST, contents of TAG and MDA and the UCP2 expression in liver tissues of the model group increased obviously, while the level of liver GSH decreased. Compared with rats in the model group, the above biomarkers in the treatment groups were improved significantly. The mixture of Dangyao and Shuifeiji extracts can decrease the susceptibility and degree of liver injury induced by hepatotoxin in rats with NAFLD. Regulation of the balance of pro- and anti-oxidative stress factors is involved in the mechanism.