Malathion-induced hepatotoxicity in rats: The effects of vitamins C and E

The subchronic exposure to malathion, an organophosphate pesticide, causes lipid peroxidation, oxidative stress, and tissue damage in rats: the protective role of resveratrol

The present study was planned to evaluate the protective role of resveratrol (Res) against subchronic malathion exposure in rats over four weeks. In total, 48 Wistar rats were used and divided equally into six groups. The groups were designed as the control group (received only a rodent diet and tap water), the corn oil group (0.5 ml corn oil by the oral route), and the malathion group (100 mg kg-1 day-1 by the oral route). Other three groups received malathion (100 mg kg-1 day-1) plus Res (5, 10, and 20 mg kg-1 day-1, respectively) by the oral route. Malathion increased malondialdehyde and 8-OHdG levels, whereas it decreased glutathione levels. Also, acetylcholinesterase, superoxide dismutase, and catalase activities were found to be low in the blood, liver, kidney, heart, and brain tissues. Biochemical parameters were not notably changed in all groups. In contrast, Res treatment inverted malathion-induced oxidative stress, lipid peroxidation, and activity of enzymes. Additionally, malathion-induced histopathological changes in the liver, kidney, heart, and brain were ameliorated by Res treatment. These results demonstrate that malathion increases oxidative stress and decreases the antioxidant status while Res has a protective function against malathion toxicity in rats.

Evaluation of oxidative stress indices after exposure to malathion and protective effects of ascorbic acid in ovarian tissue of adult female rats

Background

Malathion is one of organophosphate pesticides that is extensively used in farming and crops to control pests. Malathion induces oxidative stress in the various tissues such as the reproductive system.

Objective

To determine the effects of malathion on malondialdehyde (MDA) level and glutathione (GSH) content in female rat ovary tissue as well as to assess the protective role of Ascorbic Acid.

Methods

This study was carried out at the Department of Anatomy and Cell Biology (School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran) in 2015. In this experimental study, 30 adult, female, Wistar rats (weight range: 200-250 g) were divided into five groups, each group consisting of six rats: control group (no interventions), sham group (normal saline 0.9% 50 mg/kg), experimental group 1 (Ascorbic Acid 200 mg/kg), experimental group 2 (malathion 50 mg/kg), and experimental group 3 (malathion 50 mg/kg + Ascorbic Acid 200 mg/kg). Malathion, solvents and Ascorbic Acid were injected intraperitoneally. After two weeks, the animals were anaesthetized with intraperitoneal ketamine/xylazine (60 and 6 mg/kg, respectively) and then scarified, and the right ovarian was used to measure levels of MDA, a marker of lipid peroxidation, and GSH content. Data were analyzed by SPSS version 16, using descriptive statistics, One Way ANOVA, and Tukey-Kramer test. A p-value <0.05 was set as significance level.

Results

This study has shown that malathion increased MDA level and reduced GSH content compared with the control group (p<0.001). Also, administration of malathion in combination with Ascorbic Acid, reduced MDA level and increased the GSH content in rat ovarian tissue.

Conclusion

Malathion induced lipid peroxidation and Oxidative stress in the ovarian of Rats. In addition, it appears that Ascorbic Acid, due to its antioxidant, can recover malathion-induced poisonous changes.

Evaluation of attenuative effect of tert-butylhydroquinone against diazinon-induced oxidative stress on hematological indices in male Wistar rats

Diazinon is an organophosphate toxicant that has been identified to induce oxidative stress within biological systems through altering biochemical and hematological indices, by generating free radicals while deteriorating the cellular antioxidant defense system. The present study was designed to evaluate the effectiveness of tert-butylhydroquinone (TBHQ), a synthetic food additive, in serving as an antioxidant against sub-lethal diazinon-induced oxidative stress in male Wistar rats. Animals were randomly divided into 4 groups: Control (treated with corn oil as a vehicle), diazinon (10 mg/kg/day), TBHQ (0.028 g/kg of diet) and a combination group of TBHQ (0.028 g/kg of diet) plus diazinon (10 mg/kg/day). All animals were treated orally once a day by gastric tube and treatments were continued for 7 weeks. Hematological indices, including red blood cell (RBC) indices and white blood cell (WBC) and platelet counts, were measured at the end of the treatment schedule. On comparison of the treatment groups with the untreated control group, RBC count, hemoglobin (Hb), hematocrit (Hct), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) were significantly decreased in the diazinon and TBHQ+diazinon groups, while MCHC in the TBHQ group and MCV in the diazinon and TBHQ+diazinon groups were significantly increased. When the diazinon and TBHQ+diazinon groups were compared with the TBHQ group, RBC, Hb, Hct, and MCHC were significantly decreased whereas MCV was increased in both groups. Additionally, when comparing the TBHQ+diazinon group with the diazinon group, MCHC was determined to be significantly decreased. The results of the current experiments suggested that TBHQ could not efficiently protect blood cells against diazinon toxicity.

Malathion, an organophosphate insecticide, provokes metabolic, histopathologic and molecular disorders in liver and kidney in prepubertal male mice

The present study was undertaken to determine the effects of malathion exposure on oxidative stress, functional and metabolic parameters in kidney and liver of prepubertal male mice. For this reason, two separated groups of prepubertal male mice were used in this experiment. Animals were divided into two groups, group 1 served as a control and received the corn oil and group 2 was treated with 200 mg/kg body weight (b.w.) of malathion for 30 days. In result, we found that the malathion administration led to the perturbation of biochemical markers and histopathological as well as molecular damages. These changes were accompanied by an oxidative alternation which was evaluated by lipoperoxidation process and MDA production, a diminution of sulfhydril groups (-SH) content and an antioxidant enzyme activities depletion such as total superoxide dismutase (SOD) and its isoforms, catalase (CAT) and glutathione peroxidase (GPx) in both kidney and liver tissues. These changes were related with many histopathological lesions in the liver and kidney tissues. More importantly, this insecticide clearly caused a decline in the GPx-4 expression in liver as well as GPx-3 in kidney. These data suggest that prepubertal male mice exposure to malathion showed a marked deregulation of liver and kidney functions.

Thymoquinone attenuates hepatotoxicity and oxidative damage caused by diazinon: an in vivo study

Thymoquinone (TQ) is the main active constituent of Nigella sativa seeds. The objective of this study was to explore the protective effects of TQ on diazinon (DZN)-induced liver toxicity in the mouse model. The animals were divided into five groups of 6 each and treated intraperitoneally. Group 1 received the vehicle, group 2 was given 16 mg/kg DZN, group 3 received 5 mg/kg TQ, and groups 4 and 5 were treated with 1.25 and 5 mg/kg of TQ as well as 16 mg/kg DZN, respectively. Finally, butyrylcholinesterase (BChE), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) serum activity as well as nitric oxide (NO), lipid peroxidation (LPO), total antioxidant capacity (TAC), total thiol molecule (TTM), and histopathological experiments were evaluated in the liver samples. Our findings showed that DZN caused a significant increase in ALT (P < 0.01), AST (P < 0.001), ALP (P < 0.001) serum levels, LPO (P < 0.001) and NO (P < 0.001), the depletion of the TAC (P < 0.05) and TTM (P < 0.001), and structural changes in the liver tissue. Following TQ administration, a significant improvement was observed in the oxidative stress biomarkers in the liver tissue. In addition, our biochemical findings were correlated well to the histopathological examinations. In conclusion, the data from this study indicate that the administration of TQ may prevent liver damage by preventing free radical formation in animals exposed to DZN.

The ameliorating effects of selenium and vitamin C against fenitrothion-induced blood toxicity in Wistar rats

Fenitrothion is widely used organophosphate pesticide in agriculture and health programs, but besides, it causes several toxic effects. The present study was designed to evaluate the possible protective effects of selenium (0.5mg/kg b.w.) and vitamin C (100mg/kg b.w) on altered haematological, biochemical and oxidative stress parameters in the blood of rats orally treated with fenitrothion (20mg/kg b.w) for 30days. Fenitrothion caused changes in body weight, food and water intake, and some haematological and biochemical parameters. Fenitrothion altered the glutathione redox status (GSH and GSSG) and decreased activity of antioxidant enzymes (GSH-Px, GST, SOD and CAT), leading to a lipid peroxidation. Selenium and vitamin C, by improving the activity of antioxidants, reduced oxidative stress and a lipid peroxidation, maintaining the values of examined parameters to optimal levels. Therefore, selenium and vitamin C could be useful in providing protection of exposed non-target organisms including people from fenitrothion.

Effects of phoxim-induced hepatotoxicity on SD rats and the protection of vitamin E

Currently, public pay more attention to the adverse effect of organophosphate pesticides on human and animal health and on the environment in developing nations. Vitamin E may protect the hepatocyte and increase the function of liver. The study was to investigate the effects of phoxim-induced hepatotoxicity on Sprague Dawley (SD) rats and the protection of vitamin E. SD rats received by gavage 180 mg kg^-1 (per body weight) of phoxim, 200 mg kg^-1 (per body weight) of vitamin E, and phoxim + vitamin E. The results showed that exposure to phoxim elevated liver coefficient; glutamyl transpeptidase (GGT), aspartate aminotransferase, alkaline phosphatase, total bilirubin, total bile acid, and alanine aminotransferase in the serum; ROS in the liver; and the expression of p53, Bax, CYP2E1, ROS, caspase-9, caspase-8, and caspase-3, while phoxim caused a reduction of total protein, albumin, and cholinesterase in the serum; acetylcholinesterase, total antioxidant capacity, glutathione peroxidase, and glutathione in the liver; and the expression of Bcl-2. Vitamin E modified the phoxim-induced hepatotoxicity by reducing the GGT in the serum, malondialdehyde in the liver, and the expression of CYP2E1 significantly. There were no significant changes of globulin in the serum, the activity of catalase in the liver, as well as expression levels of Fas and Bad in the liver. Overall, subacute exposure to phoxim induced hepatic injury, oxidative stress damage, and cell apoptosis. Vitamin E modified phoxim-induced hepatotoxicity slightly. And, vitamin E minimized oxidative stress damage and ultrastructural changes in rat hepatocytes notably.

Protective role of antioxidants capacity of Hyrtios aff. Erectus sponge extract against mixture of persistent organic pollutants (POPs)-induced hepatic toxicity in mice liver: biomarkers and ultrastructural study

The current study investigates the hepatoprotective effect of Hyrtios aff. Erectus sponge extract against POPs intoxication on endogenous antioxidant enzymes and lipid peroxidation in mice liver tissue. In the present study, the mice BALB/C were assigned into four groups: group I: received saline subcutaneously for 7 days and served as negative control; group II: received subcutaneously for 7 days, 130.6 mg/100 g/b. w/day POPs mixture(mixture of PCB 28, PCB 52,, PCB 101, PCB 118, PCB 153, PCB 138 and PCB 180, alpha-Hexachlorocyclohexane, beta-Hexachloro-cyclohexane, gamma-hexachlorocyclohexane, Aldrin, O,P'-DDE, Dieldrin, P,p DDE, O,P DDD, Endrin, P,p DDD and P,pDDT were extracted from sediments collected from Lake Mariout), and served as induced group; group III: pretreated with Hyrtios aff. Erectus sponge extract for 7 days, as a protection dose and then treated with POPs as group II and served as protective group; and group IV: received i.p Hyrtios aff. Erectus sponge extract of dose 0.7 mg/100 g b.wt/day for 7 days and served as positive control. After 7 days (experimental period), mice were scarified and the liver was harvested for biochemical estimation. Significant reduction in lipid peroxidation (p < 0.002) was noticed compared to POPs-protected group. The antioxidant biomarkers levels were significantly increase as the hepatic GSH and GST increased by 69.9 and 89.9%, respectively. Such increase was accompanied by a decrease in tyrosine kinase activity by 59.82%, additionally remarkable histopathological changes in liver tissue indicate the protective effect of Hyrtios aff. Erectus sponge extract. The results of this study revealed that the Hyrtios aff. Erectus sponge extract has the potential to diminish the destructive effect of POPs intoxication through enhancement of the endogenous antioxidant status. The hepatoprotective activity of Hyrtios aff. Erectus sponge extract is mediated, by the antioxidant effect of its active constituents. The active constituents of Hyrtios aff. Erectus sponge extract were identified by LC-MS/MS.

Involvement of superoxide in malaoxon-induced toxicity in primary cultures of cortical neurons

Organophosphorus compounds (OP) represent a class of insecticides that are used most globally. The neurotoxic effects are attributed mainly to acetylcholinesterase (AChE) enzyme inhibition, which is responsible for cholinergic manifestations in individuals acutely exposed to OP. However, AChE inhibition alone cannot account for the wide range of symptoms that were reported following OP exposures. In agreement with this, evidence shows that non-cholinergic events may be mechanistically linked to OP-induced neurotoxicity. The aim of this study was to investigate the potential occurrence of oxidative stress as a critical step in the toxicity induced by the OP malaoxon(MAL) using primary cultures of mouse cortical neurons, as well as to distinguish MAL-induced oxidative stress and cell toxicity from an action on AChE blockade. Primary cultures of mouse cortical neurons were treated with MAL (0.01; 0.1; 1; 10; or 100 µM) at varying time points (1, 3, 6, 24, 48, or 144 hr) and the following biochemical parameters determined including cell viability, AChE activity, and superoxide production. MAL significantly reduced cell viability in a concentration- and time-dependent manner. Of note, 1 µM MAL significantly inhibited (approximately 75%) AChE activity after 48 hr incubation. Pralidoxime (PRAL) (600 µM), a classical AChE reactivator, significantly protected against MAL-induced AChE blockade; however, PRAL did not affect MAL-mediated fall in cellular viability, indicating that AChE inhibition is not necessarily correlated with insecticide-induced decrease in cell survival. MAL-induced diminished cell viability was preceded by a significant increase in superoxide anion production. The antioxidant agent ascorbic acid (AA) (200 µM), which significantly protected against MAL-induced superoxide anion production, did not alter MAL-induced AChE inhibition and significantly prevented insecticide-mediated fall in cell survival. Data show that increased superoxide anion production is an event that precedes MAL-induced cell toxicity in primary cultures of mouse cortical neurons. Based on the preventative effects of AA against MAL-mediated superoxide anion production and reduced cell viability, evidence indicates that oxidative stress represents an important step mediating MAL-induced toxicity in neurons and that AChE inhibition is not necessarily correlated with lowered cell survival noted in insecticide-exposed cells.

Oxidative stress as a damage mechanism in porcine cumulus-oocyte complexes exposed to malathion during in vitro maturation

Malathion is one of the most commonly used insecticides. Recent findings have demonstrated that it induces oxidative stress in somatic cells, but there are not enough studies that have demonstrated this effect in germ cells. Malathion impairs porcine oocyte viability and maturation, but studies have not shown how oxidative stress damages maturation and which biochemical mechanisms are affected in this process in cumulus-oocyte complexes (COCs). The aims of the present study were to determine the amount of oxidative stress produced by malathion in porcine COCs matured in vitro, to define how biochemical mechanisms affect this process, and determine whether trolox can attenuate oxidative damage. Sublethal concentrations 0, 750, and 1000 µM were used to evaluate antioxidant enzyme expressions, reactive oxygen species (ROS production), protein oxidation, and lipid peroxidation, among other oxidation products. COCs viability and oocyte maturation decreased in a concentration-dependent manner. Malathion increased Cu, Zn superoxide dismutase (SOD1), glutathione-S-transferase (GST), and glucose 6 phosphate dehydrogenase (G6PD) protein level and decreased glutathione peroxidase (GSH-Px) and catalase (CAT) protein level. Species reactives of oxygen (ROS), protein oxidation and Thiobarbituric acid reactive substances (TBARS) levels increased in COCs exposed to the insecticide, but when COCs were pre-treated with the trolox (50 µM) 30 min before and during malathion exposure, these parameters decreased down to control levels. This study showed that malathion has a detrimental effect on COCs during in vitro maturation, inducing oxidative stress, while trolox attenuated malathion toxicity by decreasing oxidative damage.

Exposure to the mixture of organophosphorus pesticides is embryotoxic and teratogenic on gestational rats during the sensitive period

Mixture of organophosphorus pesticides (MOPs) has been used worldwide to increase food production. The MOPs are harmful, and the exposure to them is both agricultural and nonagricultural through contaminated food. The neurotoxicity of MOPs has received more consideration recently due to the increased cases of malformed fetuses suspected to be caused by the MOPs exposure during gestation; however, relevant studies in animal model are rare. In this study, we performed a comprehensive analysis and demonstrated potential perinatal embryotoxicity and teratogenicity of MOPs exposure. As results, we found that MOPs decreased in utero fetal growth and alter the ratio of organs to whole body weight of the pregnant rats. MOPs also had been shown to disturb the balance of sex hormones and affect the reproduction of rats. Furthermore, we found various significantly elevated deformities in MOPs exposed embryos, confirming the embryotoxic and teratogenic effects of maternal exposure to MOPs. © 2015 Wiley Periodicals, Inc. Environ Toxicol 32: 139-146, 2017.

Impact of Exposure to Fenitrothion on Vital Organs in Rats

This study was designed to investigate the impact of oral administration of fenitrothion (10 mg/kg) on liver, kidney, brain, and lung function in rats. The effect was studied on days 7, 14, 21, 28, and 42. Our results have shown deterioration in liver function as evidenced by the elevation in serum ALT, AST, ALP, and bilirubin and reduction in albumin and hepatic glycogen. This was associated with a state of hyperglycemia and hyperlipidemia and increased prothrombin time, while hemoglobin content was reduced. In addition, the kidney function was reduced as indicated by the elevation in serum creatinine, uric acid, and BUN, while the serum levels of magnesium, potassium, and sodium were reduced. This study also showed an impairment in brain neurotransmitter (elevated 5-HT, glutamate, GABA, and reduced dopamine and norepinephrine level). This was associated with a reduction in the barrier capacity in brain and lung. Fenitrothion also caused a decrease in cholinesterase activity in serum, lung, and brain activity associated with a state of oxidative stress in all tested organs and hyperammonemia. These results support the hazards of pesticide use and shows the importance of minimizing pesticide use or discovering new safe pesticides.

Furan-induced hepatotoxic and hematologic changes in diabetic rats: the protective role of lycopene

Furan forms as a result of thermal treatment of food and induces harmful effects on organisms. In our work, lycopene, furan, and a combination of the two were given to diabetic male rats for 28 days. Hematological changes, total protein and cholesterol, triglyceride, and albumin levels, alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, and alkaline phosphatase activities of the serum, malondialdehyde levels, glutathione peroxidase, catalase, glutathione-S-transferase, superoxide dismutase activities, DNA damage in liver tissues and hepatic histopathological alterations were compared to a control group. There were significant changes in the liver function tests, DNA damage, activities of antioxidant enzymes, and malondialdehyde levels between diabetic control and non-diabetic control groups, between diabetic control and diabetic lycopene groups, and also between diabetic furan and diabetic control groups. In diabetic lycopene and diabetic furan + lycopene treated groups we designated the preventive effects of lycopene against diabetes and furan, however, on the analysed parameters only. In spite of some pathological alterations designated in diabetic furan treated group’s liver, fewer pathological alterations were observed in furan+lycopene treated groups at the end of week 4. Consequently, lycopene significantly reduced furan- and diabetes-induced toxicity in rat liver.

Evaluating genotoxic risks in Brazilian public health agents occupationally exposed to pesticides: a multi-biomarker approach

This is the first study demonstrating genotoxic effects and whole transcriptome analysis on community health agents (CHAs) occupationally exposed to pesticides in Central Brazil. For the transcriptome analysis, we found some genes related to Alzheimer's disease (LRP1), an insulin-like growth factor receptor (IGF2R), immunity genes (IGL family and IGJ), two genes related to inflammatory reaction (CXCL5 and CCL3), one gene related to maintenance of cellular morphology (NHS), one gene considered to be a strong apoptosis inductor (LGALS14), and several transcripts of the neuroblastoma breakpoint family (NBPF). Related to comet assay, we demonstrated a significant increase in DNA damage, measured by the olive tail moment (OTM), in the exposed group compared to the control group. Moreover, we also observed a statistically significant difference in OTM values depending on GSTM1 genotypes. Therefore, Brazilian epidemiological surveillance, an organization responsible for the assessment and management of health risks associated to pesticide exposure to CHA, needs to be more proactive and considers the implications of pesticide exposure for CHA procedures and processes.

Lipoic acid attenuates Aroclor 1260-induced hepatotoxicity in adult rats

The present study was aimed to investigate the mechanistic aspect of Aroclor 1260-induced hepatotoxicity and its protection by lipoic acid. The adult male Albino rats were divided into six groups. Group I served as control. Group II received lipoic acid (35 mg/kg/day). Aroclor 1260 was given to rats by oral gavage at doses 20, 40, or 60 mg/kg/day (Groups III, IV, and V, respectively). Group VI was pretreated with lipoic acid (35 mg/kg/day) 24 h before Aroclor 1260 (40 mg/kg/day). Treatment in all groups was continued for further 15 consecutive days. Serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase activities and total bilirubin, total cholesterol, and triglycerides were significantly increased while total protein, total albumin, and high-density lipoprotein were significantly decreased. Hydrogen peroxide production and lipid peroxidation were significantly increased while superoxide dismutase and catalase activities and reduced glutathione (GSH) content was significantly decreased in liver. Caspase-3 & -9 activities were significantly increased in liver. Lipoic acid pretreatment significantly reverted all these abnormalities toward their normal levels. In conclusion, Aroclor 1260 induced liver dysfunction, at least in part, by induction of oxidative stress. Apoptotic effect of hepatic cells is involved in Aroclor 1260-induced liver injury. Lipoic acid could protect rats against Aroclor 1260-induced hepatotoxicity. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 913-922, 2016.

Evaluating the protective effects of vitamin C on serum and erythrocyte cholinesterase activity of male rats exposed to malathion

Introduction

Malathion is one of organophosphate poisons (OPPs) that inhibit cholinesterase activity and induce oxidative stress in target organs, such as the reproductive system. The aim of this study was to assess the effects of Malathion on serum and erythrocyte cholinesterase activity in male rats and also to assess the protective effects of vitamin C in this regard.

Methods

This experimental study was performed in the Pharmacology Laboratory of the Pharmacy Faculty and in the Advanced Histology Techniques Laboratory of the Medical Faculty of Mashhad University of Medical Sciences (MUMS) in January 2014. Thirty male wistar rats, weighting 200–250 g, were divided into five groups of six. The different groups were exposed as follows: group 1: Malathion 50 mg/kg; group 2: Vitamin C; group 3: Malathion plus Vitamin C with the specified doses; sham group: normal saline; and control group: no exposure. After six weeks, 3 ml blood samples were taken from the rats, and titrimetric and Ellman methods were used to assess serum and erythrocyte cholinesterase activity, respectively. The data was analyzed by SPSS 16, and p < 0.05 was considered significant.

Results

The activities of serum and erythrocyte cholinesterase were inhibited significantly in the Malathion exposed group compared to the control group (p < 0.001). The administration of Vitamin C alone significantly increased the activities of serum and erythrocyte cholinesterase. The serum and erythrocyte cholinesterase inhibition showed improvement in the group that received both Malathion and Vitamin C.

Conclusion

Malathion reduced the activities of serum and erythrocyte cholinesterase in exposed animals. It probably has the same intoxication effects on people who are exposed. Improvement of cholinesterase activity by antioxidant effects of Vitamin C suggests that Vitamin C supplementation can be used to decrease side effects of OPP exposure.

Mercuric chloride induced hepatotoxic and hematologic changes in rats

This study focuses on investigating the possible protective effect of sodium selenite (Na2SeO3) and/or vitamin E against mercuric chloride (HgCl2)-induced hepatotoxicity in rat. Male rats were given HgCl2 (1 mg/kg body weight (bw)) and HgCl2 plus Na2SeO3 (0.25 mg/kg bw) and/or vitamin E (100 mg/kg bw) daily via gavage for 4 weeks. HgCl2-treated groups had significantly higher white blood cell and thrombocyte counts than the control group. Serum activities of alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, γ-glutamyl-transferase, and lactate dehydrogenase significantly increased and serum levels of total protein, albumin, triglyceride, total cholesterol, and low-density lipoprotein cholesterol significantly decreased in the HgCl2-treated groups compared with control group. Malondialdehyde level significantly increased and superoxide dismutase, catalase, and glutathione peroxidase activities decreased in liver tissue of HgCl2-treated rats. Also, HgCl2 exposure resulted in histopathological changes. Supplementation of Na2SeO3 and/or vitamin E provided partial protection in hematological and biochemical parameters that were altered by HgCl2. As a result, Na2SeO3 and/or vitamin E significantly reduced HgCl2-induced hepatotoxicity, but not protected completely.

Toxic effects of methamidophos on paraoxonase 1 activity and on rat kidney and liver and ameliorating effects of alpha-tocopherol

The role of alpha-tocopherol on nephrotoxicity and hepatotoxicity induced by methamidophos (MT) was investigated in wistar rats. Animals were given via gavage, for four weeks, a low dose of MT (MT1), a high dose of MT (MT2), vitamin E (200 mg/kg of bw) or both MT2 plus vitamin E (Vit E) and control group was given distillate water. MT treatment resulted in a significant decrease in the body weight of MT2-treated group. Moreover, MT-treated groups had significantly lower butyrylcholinesterase (p < 0.01) and paraoxonase 1 (PON1) activities compared with the control group (p < 0.05). However, MT2-treated group had significantly higher alkaline phosphatase activity compared with untreated rats (p < 0.05). Both MT-treated groups had significantly higher urea (p < 0.01) and uric acid levels (p < 0.05) compared with the control group. However, significant low uric acid level (p < 0.05) was noted in MT2 plus vit E-treated rats compared with MT2-treated group. Histopathological changes in organ tissues were observed in both MT-treated groups and MT2 plus vit E-treated rats. However, the damage was reduced in MT2 plus vit E-treated rats. Therefore, this study deduces that alpha-tocopherol administration may ameliorate the adverse effects of subacute exposure to MT on rat liver and kidney and this antioxidant can protect PON1 from oxidative stress induced by this organophosphorus pesticide. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 842-854, 2016.

Autophagy protects against dasatinib-induced hepatotoxicity via p38 signaling

Liver dysfunction is a common side effect associated with the treatment of dasatinib and its mechanism is poorly understood. Autophagy has been thought to be a potent survival or death factor for liver dysfunction, which may shed the light on a novel strategy for the intervention of hepatotoxicity caused by dasatinib. In this study, we show for the first time that autophagy is induced, which is consistent with the formation of liver damage. Autophagy inhibition exacerbated dasatinib-induced liver failure, suggesting that autophagy acted as a self-defense mechanism to promote survival. Oxidative stress has been shown to be an important stimulus for autophagy and hepatotoxicity. Interestingly, dasatinib increased the activity of p38, which is a critical modulator of the oxidative stress related to liver injury and autophagy. p38 silencing significantly blocked LC3-II induction and p62 reduction by dasatinib, which was accompanied by increased caspase-3 and PARP cleavage, indicating that autophagy alleviated dasatinib-induced hepatotoxicity via p38 signaling. Finally, the p38 agonist isoproterenol hydrochloride (ISO) alleviated dasatinib-induced liver failure by enhancing autophagy without affecting the anticancer activity of dasatinib. Thus, this study revealed that p38-activated autophagy promoted survival during liver injury, which may provide novel approaches for managing the clinical applications of dasatinib.

Satkara (Citrus macroptera) Fruit Protects against Acetaminophen-Induced Hepatorenal Toxicity in Rats

Although Citrus macroptera (Rutaceae), an indigenous fruit in Bangladesh, has long been used in folk medicine, however, there is a lack of information concerning its protective effects against oxidative damage. The protective effects of an ethanol extract of Citrus macroptera (EECM) against acetaminophen-induced hepatotoxicity and nephrotoxicity were investigated in rats. Rats (treatment groups) were pretreated with EECM at doses of 250, 500, and 1000 mg/kg, respectively, orally for 30 days followed by acetaminophen administration. Silymarin (100 mg/kg) was administered as a standard drug over a similar treatment period. Our findings indicated that oral administration of acetaminophen induced severe hepatic and renal injuries associated with oxidative stress, as observed by 2-fold higher lipid peroxidation (TBARS) compared to control. Pretreatment with EECM prior to acetaminophen administration significantly improved all investigated biochemical parameters, that is, transaminase activities, alkaline phosphatase, lactate dehydrogenase, γ-glutamyl transferase activities and total bilirubin, total cholesterol, triglyceride and creatinine, urea, uric acid, sodium, potassium and chloride ions, and TBARS levels. These findings were confirmed by histopathological examinations. The improvement was prominent in the group that received 1000 mg/kg EECM. These findings suggested that C. macroptera fruit could protect against acetaminophen-induced hepatonephrotoxicity, which might be via the inhibition of lipid peroxidation.

Hepatotoxicity and nephrotoxicity induced by the chlorpyrifos and chlorpyrifos-methyl metabolite, 3,5,6-trichloro-2-pyridinol, in orally exposed mice

3,5,6-Trichloro-2-pyridinol (TCP) is a primary degradation product of chlorpyrifos and chlorpyrifos-methyl. TCP has longer half-life in soil and greater solubility in water than its parent compound, and cause wide contamination in environments. However, studies about the toxic effects of TCP are limited and outdate. In this study, 5 mg/kg/day, 50 mg/kg/day, and 150 mg/kg/day TCP were given to male mice through gavage for four weeks. As a result, the final body weights of TCP treated groups were significantly lower than control, and the relative organ weights of the liver and kidney were significantly higher than that of control. In addition, NMR-based metabolomics was used to investigate the toxic effects of TCP. It was found that a total of 39 serum metabolites were significantly changed in the TCP-treated groups, and these metabolites are related to hepatotoxicity and nephrotoxicity. These results were also confirmed by histopathology, serum biochemical, and oxidative stress analysis. In addition, metabolic disturbances due to TCP exposure were also observed based on altered metabolites. As far as we know, these results are the first to show the metabolomic toxicity of TCP, which warrants further research.

A model of chlorpyrifos distribution and its biochemical effects on the liver and kidneys of rats

This study investigated the main target sites of chlorpyrifos (CPF), its effect on biochemical indices, and the pathological changes observed in rat liver and kidney function using gas chromatography/mass spectrometry. Adult female Wistar rats (n = 12) were randomly assigned into two groups (one control and one test group; n = 6 each). The test group received CPF via oral gavage for 21 days at 5 mg/kg daily. The distribution of CPF was determined in various organs (liver, brain, heart, lung, kidney, ovary, adipose tissue, and skeletal muscle), urine and stool samples using GCMS. Approximately 6.18% of CPF was distributed in the body tissues, and the highest CPF concentration (3.80%) was found in adipose tissue. CPF also accumulated in the liver (0.29%), brain (0.22%), kidney (0.10%), and ovary (0.03%). Approximately 83.60% of CPF was detected in the urine. CPF exposure resulted in a significant increase in plasma transaminases, alkaline phosphatase, and total bilirubin levels, a significant reduction in total protein levels and an altered lipid profile. Oxidative stress due to CPF administration was also evidenced by a significant increase in liver malondialdehyde levels. The detrimental effects of CPF on kidney function consisted of a significant increase in plasma urea and creatinine levels. Liver and kidney histology confirmed the observed biochemical changes. In conclusion, CPF bioaccumulates over time and exerts toxic effects on animals.

A comparative study on toxicity induced by carbosulfan and malathion in Wistar rat liver and spleen

Organophosphorus (OP) and carbamate (CM) pesticides are widely used in agriculture. These pesticides are highly toxic to humans and their residues in food pose potential threat to human health. In this comparative study, we investigated the effect of subchronic exposure of OPs (malathion, MAL) and CM (Carbosulfan, CB) on rat liver and spleen. Biochemical analysis showed that levels of hepatic enzymes (ALT, ALP, LDH and PAL) changed after exposure to the pesticides. In the liver extracts, lipid peroxidation index increased after the treatment by pesticides. Our results indicated that exposure to MAL and CB leads to alteration of liver redox status. Both pesticides induced focal inflammation and fibrosis in the liver. After subchronic administration of MAL (200 mg/kg) and CB (25 mg/kg), systemic inflammation, as depicted by the increase in IFN-δ activity in liver, was observed in both malathion and carbosulfan treated animals. In addition, the results showed that MAL significantly increased TCD4+ and TCD8+ lymphocyte number. It also decreased INF-δ and IL-4 production. However, CB induced a reduction of TCD8+ number and cytokine production in spleen cells. In conclusion, malathion and carbosulfan had significant immunomodulatory properties in the spleen with inflammation and oxidative stress induction in the liver.

Changes in glucose metabolism and reversion of genes expression in the liver of insulin-resistant rats exposed to malathion. The protective effects of N-acetylcysteine

Organophosphorus pesticides are known to disturb glucose homeostasis and increase incidence of metabolic disorders and diabetes via insulin resistance. The current study investigates the influence of malathion on insulin signaling pathways and the protective effects of N-acetylcysteine (NAC). Malathion (200 mg/kg) and NAC (2 g/l) were administered orally to rats, during 28 consecutive days. Malathion increases plasma glucose, plasma insulin and glycated hemoglobin levels. Further, we observed an increase of insulin resistance biomarkers and a decrease of insulin sensitivity indices. The GP, GSK3β and PEPCK mRNA expressions were amplified by malathion while, the expression of glucokinase gene is down-regulated. On the basis of biochemical and molecular findings, it is concluded that malathion impairs glucose homeostasis through insulin resistance and insulin signaling pathways disruptions in a way to result in a reduced function of insulin into hepatocytes. Otherwise, when malathion-treated rats were compared to NAC supplemented rats, fasting glucose and insulin levels, as well as insulin resistance indices were reduced. Furthermore, NAC restored liver GP and PEPCK expression. N-acetylcysteine showed therapeutic effects against malathion-induced insulin signaling pathways disruption in liver. These data support the concept that antioxidant therapies attenuate insulin resistance and ameliorate insulin sensitivity.

Subacute and subchronic toxicity of Avalon(®) mixture (bentazone+dicamba) to rats

Subacute and subchronic toxicity of the herbicide Avalon(®), a mixture of bentazone and dicamba, were tested on rats. Avalon(®) was administered at dose levels of 250, 500 and 1000mg/kg body weight/day for 28 and 90 days. Alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) activities were monitored together with biochemistry parameters. The results showed that the mixture caused increases in the activities of ALT, AST and ALP, elevated concentrations of sodium, albumin and albumin/globulin ratio in males. In females, ALT activity, cholesterol and phosphate levels were increased. The changes generally were dose related and, in most cases, females exhibited lower susceptibility than males. The effects of a mixture are, in the most cases, different from the effects of the individual substances. The effects of bentazone were not prevalent which would be expected taking the composition of the mixture into account.

Antioxidants in organophosphorus compounds poisoning

Oxidative stress has recently been implicated as a factor in the mortality and morbidity induced by organophosphorus (OP) compound poisoning. An overwhelming number of research papers are based on studying at the cellular and organ level. Such studies have concluded that antioxidants can be used as an adjunct compound in the treatment of both chronic as well as acute OP poisoning. Still, the role of antioxidants in reducing the mortality and morbidity induced by OP compounds has scarcely been verified, as well as their role as adjunct treatment compounds for both structurally and functionally different OP compounds. The present review of the literature was undertaken to establish the role of antioxidants in survival studies following acute exposure to OP compounds. The review found no substantial evidence that antioxidants demonstrate any positive effect following extremely toxic poisoning. However, for a more comprehensive and rational conclusion, further research needs to be conducted.

Hepatoprotective and Renoprotective Effects of Lavender (Lavandula stoechas L.) Essential Oils Against Malathion-Induced Oxidative Stress in Young Male Mice

We aimed in the present study to investigate the hepato- and nephroprotective effects of Lavandula stoechas essential oils (LSEO) against malathion-induced oxidative stress in young male mice as well as the possible mechanism implicated in such protection. Animals were divided into eight groups of 12 each: Control, malathion (200 mg/kg b.w.); Various doses of LSEO (10, 30, and 50 mg/kg b.w.), malathion+various doses of LSEO. Malathion and LSEO were daily per orally (p.o.) administered by intragastric gavage during 30 days. We initially found that malathion treatment induced body weight gain decrease as well as a clear nephro- and hepatotoxicity as assessed by significant relative liver and kidney weight increase and related hemodynamic parameters deregulation. Malathion exposure of mice also induced a considerable perturbation of metabolic parameters. On the other hand, we showed that malathion administration was accompanied by an oxidative stress status assessed by an increase of malondialdehyde (MDA) and hydrogen peroxide (H2O2) levels as well as a depletion of sulfhydril group content (-SH) and antioxidant enzyme activities such as catalase (CAT) and glutathione peroxidase (GPx), total superoxide dismutase (SOD), Cu/Zn-SOD, Mn-SOD, and Fe-SOD in the kidney and liver. More importantly, LSEO treatment abolished all malathion-induced body gain loss, liver and kidney relative weight increase, hemodynamic and metabolic disorders, as well as hepatic and renal oxidative stress. In conclusion, our data suggest that LSEO exerted potential hepato- and nephroprotective effects against malathion-induced oxidative stress in mice. The beneficial effect of LSEO might be related, in part, to its antioxidant properties.

Selenium modulates β-cyfluthrin-induced liver oxidative toxicity in rats

This study was designed to investigate the possibility of β-cyfluthrin to induce oxidative stress and biochemical perturbations in rat liver and the role of selenium in alleviating its toxic effects. Male Wister rats were randomly divided into four groups of seven each, group I served as control, group II treated with selenium (200 µg/kg BW), group III received β-cyfluthrin (15 mg/kg BW, 1/25 LD50 ), and group IV treated with β-cyfluthrin plus selenium. Rats were orally administered their respective doses daily for 30 days. The administration of β-cyfluthrin caused elevation in lipid peroxidation (LPO) and reduction in the activities of antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), glutathione peroxidase (GPx), and glutathione reductase (GR). A decrease in reduced glutathione (GSH) content was also observed. Liver aminotransferases (AST and ALT) and alkaline phosphatase (ALP) were decreased, whereas lactate dehydrogenase (LDH) was increased. Selenium in β-cyfluthrin-induced liver oxidative injury of the rats modulated LPO, CAT, SOD, GSH, GST, GPx, and GR. Also, liver AST, ALT, ALP, and LDH were maintained near normal level due to selenium treatment. It is concluded that selenium scavenges reactive oxygen species and render a protective effect against β-cyfluthrin toxicity.

Association of inflammatory response and oxidative injury in the pathogenesis of liver steatosis and insulin resistance following subchronic exposure to malathion in rats

Insulin resistance and risk of type 2 diabetes are the most important complications following exposure to organophosphorous (OPs) pesticides. Regarding the importance of liver on metabolic pathways regulation, in particular blood glucose homeostasis, we focused on liver inflammation and oxidative damages in a subchronic model of toxicity by malathion. Adult male Wistar rats of body weight 200-250g were used for the study. Malathion (200mg/kg b.w./day) was administered to rats by oral intubation for 28 days. Glycemic and insulin resistance indices, markers of liver injury, markers of inflammation and oxidative stress were assessed. Malathion-treated rats showed increased glycemia, insulinemia and glycated hemoglobin level, HOMA-IR and HOMA-β indices, plasma activities of hepatocellular enzymes, lipid peroxidation index, CD3(+)/CD4(+) and CD3(+)/CD4(+) and pro-inflammatory cytokines when decreased antioxidant status in liver was noted. Most of our study indicates that malathion promotes insulin resistance, inflammation and Hepatosteatosis in subchronic model of exposure. On the basis of biochemical and molecular findings, it is concluded that insulin resistance induced by malathion occurs through oxidative stress and related pro-inflammatory markers in a way to result in a reduced function of insulin in liver cells.

Antioxidant and anti-inflammatory effects of N-acetylcysteine against malathion-induced liver damages and immunotoxicity in rats

AIMS

Occupational exposure to organophosphate pesticides is becoming a common and increasingly alarming world-wide phenomenon. The present study is designed to investigate the preventive effect of N-acetylcysteine on malathion-induced hepatic injury and inflammation in rats.

MAIN METHODS

Adult male Wistar rats of body weight 200-230 g were used for the study. Malathion (200mg/kg b.w./day) was administered to rats by oral intubation and N-acetylcysteine (2g/l) in drinking water for 28 days. Rats were sacrificed on the 28th day, 2h after the last administration. Markers of liver injury (aspartate transaminase, alanine transaminase, alkaline phosphatase and lactate desyhdogenase), inflammation (leukocyte counts, myeloperoxidase, immunophenotyping of CD4(+) and CD8(+), interleukin-1β, interleukin-6 and interferon-γ expression) and oxidative stress (lipid peroxidation, reduced glutathione and antioxidant status) were assessed.

KEY FINDINGS

Malathion induced an increase in activities of hepatocellular enzymes in plasma, lipid peroxidation index, CD3(+)/CD4(+) and CD3(+)/CD4(+) percent and pro-inflammatory cytokines, when decreased antioxidant status in liver was noted. When malathion-treated rats were compared to NAC supplemented rats, leukocytosis, T cell count and IL-1β, IL-6, INF-γ expression were reduced. Furthermore, NAC restored liver enzyme activities and oxidative stress markers.

SIGNIFICANCE

Malathion induces hepatotoxicity, oxidative stress and liver inflammation. N-acetylcysteine showed therapeutic effects against malathion toxicity.

Triazophos induced oxidative stress and histomorphological changes in liver and kidney of female albino rats

Organophosphate (OP) pesticides toxic manifestations have been associated with enhanced generation of reactive oxygen species (ROS) which culminates into oxidative stress (OS). Triazophos (TZ), a broad spectrum OP, was used in the present study to investigate toxic effects on liver and kidney of female albino rats at three sub-chronic dose levels of 1/10th, 1/20th and 1/40th of LD50 for 30 days. Activity levels of different OS parameters viz: catalase (CAT), superoxide dismutase (SOD), glutathione-S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPx) and lipid peroxidation (LPO) were differentially altered in liver and kidney of TZ treated rats as compared to control rats. Histomorphological studies further revealed number of abnormalities as infiltration, vacuolization, enlarged sinusoids and necrosis in liver of TZ treated rats, while renal histoarchitecture of 1/10th and 1/20th of LD50 TZ treated rats showed high degeneration of glomeruli. Enhanced apoptosis was also observed in hepatocytes at dose levels of 1/10th and 1/20th of LD50 TZ treated female rats. The results infer that exposure of female albino rats to TZ leads to number of pathophysiological conditions in the liver and kidney at dose dependent manner.

Hepatoprotective effect of Cymbopogon citratus aqueous extract against hydrogen peroxide-induced liver injury in male rats

BACKGROUND

Cymbopogon citratus (Poaceae) a tropical perennial herb plant that is widely cultivated to be eaten either fresh with food or dried in tea or soft drink has been reported to possess a number of medicinal and aromatic properties. This study aimed at evaluating the protective effects of C. citratus aqueous extract against liver injury induced by hydrogen peroxide (H2O2), in male rats.

MATERIALS AND METHODS

Twenty-five rats were randomly divided into five different groups of five animals in each group; (1) Control. (2) Received H2O2 (0.5%) with drinking water. (3), and (4) received H2O2 and C. citratus (100 mg·kg(-1) b wt), vitamin C (250 mg·kg(-1) b wt) respectively. (5), was given C. citratus alone. The treatments were administered for 30 days. Blood samples were collected and serum was used for biochemical assay including liver enzymes activities, total protein, total bilirubin and malonaldehyde, glutathione in serum and liver homogenates. Liver was excised and routinely processed for histological examinations.

RESULTS

C. citratus attenuated liver damage due to H2O2 administration as indicated by the significant reduction (p<0.05), in the elevated levels of ALT, AST, ALP, LDH, TB, and MDA in serum and liver homogenates; increase in TP and GSH levels in serum and liver homogenates; and improvement of liver histo-pathological changes. These effects of the extract were similar to that of vitamin C which used as antioxidant reference.

CONCLUSION

C. citratus could effectively ameliorate H2O2-induced oxidative stress and prevent liver injury in male rats.

Tocotrienol rich fraction prevents fenitrothion induced pancreatic damage by restoring antioxidant status

Fenitrothion (FNT) is extensively used as pesticide and may induce oxidative stress in various organs. Tocotrienol, a form of vitamin E found in palm oil, reduces oxidative impairments in pathological conditions. This study aims to investigate the effects of palm oil tocotrienol rich fraction (TRF) on fenitrothion-induced oxidative damage in rat pancreas. Forty male Sprague-Dawley rats were divided into four groups: control group, FNT group, TRF group and FNT+TRF group. Regimens FNT (20 mg kg(-1) b.wt.) and TRF (200 mg kg(-1) b.wt.) were force-fed for 28 consecutive days with control group only receiving corn oil. Chronic administration of fenitrothion significantly (p < 0.05) induced oxidative damage in pancreas of rats with elevated malondialdehyde and protein carbonyl level. Depletion of glutathione and significant (p < 0.05) reduction in antioxidant enzyme activities in pancreas homogenate additionally suggested induction of oxidative stress. Despite these changes in pancreas of intoxicated rats, no significant (p < 0.05) changes in blood glucose and pancreas histology were observed. Co-administration of FNT with TRF alleviated these oxidative changes and significantly (p < 0.05) restored antioxidant status. Enzymatic activities of Superoxide Dismutase (SOD) and Catalase (CAT) were normalized. In conclusion, tocotrienol rich fraction of palm oil prevents fenitrothion-induced pancreatic oxidative damage in rats.

Effect of lycopene on oxidative stress induced during D-galactosamine/lipopolysaccharide-sensitized liver injury in rats

CONTEXT

Lycopene is a phytonutrient under considerable investigation for its antioxidant benefits in treating diseases like cancer, cardiovascular diseases, osteoporosis and diabetes.

OBJECTIVE

This study explores the effect of lycopene against oxidative damage during experimental hepatitis, induced by D-galactosamine/lipopolysaccharide (D-GalN/LPS).

MATERIALS AND METHODS

Experimental rats were pretreated with lycopene intraperitoneally for 6 d (10 mg/kg body weight/day) and then induced by D-GalN/LPS. After induction, the levels of lipid peroxides in serum and liver of control and experimental group of animals were measured. The activities of enzymatic antioxidants such as superoxide dismutase, catalase, glutathione peroxidase and glutathione S-transferase and nonenzymatic antioxidants, such as reduced glutathione, vitamin C and vitamin E were also analyzed. The genotoxic effect of D-GalN/LPS was evaluated through the comet assay.

RESULTS

The elevated level of lipid peroxides induced by D-GalN/LPS was significantly (p < 0.05) reverted in lycopene pretreated animals. Lycopene administration restored (p < 0.05) the decreased activities of enzymatic and nonenzymatic antioxidant markers during D-GalN/LPS induction. The DNA strand breaks (72.3 μM) generated during d-GalN/LPS toxic injury was significantly reduced (35.5 μM) upon pretreatment with lycopene as observed by reduced tail movement in comet assay.

DISCUSSION AND CONCLUSION

There is no conclusive report about lycopene-assisted protection against free radical mediated toxic injury induced by D-GalN/LPS. Our findings reveal that lycopene effectively combated oxidative damage and protected antioxidant defense status of the cell. Pretreatment of lycopene also offers protection against the DNA damage and confirms the antioxidant nature of the phytonutreint against experimental hepatitis.

Hepatoprotective, antioxidant, and ameliorative effects of ginger (Zingiber officinale Roscoe) and vitamin E in acetaminophen treated rats

Ginger is a remedy known to possess a number of pharmacological properties. This study investigated efficacy of ginger pretreatment in alleviating acetaminophen-induced acute hepatotoxicity in rats. Rats were divided into six groups; negative control, acetaminophen (APAP) (600 mg/kg single intraperitoneal injection); vitamin E (75 mg/kg), ginger (100 mg/kg), vitamin E + APAP, and ginger + APAP. Administration of APAP elicited significant liver injury that was manifested by remarkable increase in plasma alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), arginase activities, and total bilirubin concentration. Meanwhile, APAP significantly decreased plasma total proteins and albumin levels. APAP administration resulted in substantial increase in each of plasma triacylglycerols (TAGs), malondialdhyde (MDA) levels, and total antioxidant capacity (TAC). However, ginger or vitamin E treatment prior to APAP showed significant hepatoprotective effect by lowering the hepatic marker enzymes (AST, ALT, ALP, and arginase) and total bilirubin in plasma. In addition, they remarkably ameliorated the APAP-induced oxidative stress by inhibiting lipid peroxidation (MDA). Pretreatment by ginger or vitamin E significantly restored TAGs, and total protein levels. Histopathological examination of APAP treated rats showed alterations in normal hepatic histoarchitecture, with necrosis and vacuolization of cells. These alterations were substantially decreased by ginger or vitamin E. Our results demonstrated that ginger can prevent hepatic injuries, alleviating oxidative stress in a manner comparable to that of vitamin E. Combination therapy of ginger and APAP is recommended especially in cases with hepatic disorders or when high doses of APAP are required.

Skin tumorigenic potential of benzanthrone: prevention by ascorbic acid

Benzanthrone (BA) exposed occupational workers have been found to exhibit toxicological manifestations in the skin, thus it is quite likely that long term exposure may lead to skin tumorigenicity. Thus, attempts were made to elucidate the tumor initiating and promoting potentials of pure (PBA) and commercial benzanthrone (CBA). Additionally, the preventive role of ascorbic acid (AsA) was also assessed. PBA showed tumor initiating activity while CBA demonstrated tumor initiating as well as promoting activities in two-stage mouse skin tumor protocol. Further, prior treatment of AsA to PBA and CBA followed by twice weekly application of 12-o-tetradecanoyl phorbal myristate acetate (TPA) resulted into delayed onset of tumor formation and similarly single application of 7,12-dimethylbenz [α] anthracene (DMBA) followed by twice weekly application of AsA and CBA showed an increase in the latency period. Thus, AsA showed a protective effect against CBA promoted skin tumor. Furthermore, the topical application of CBA significantly increased the levels of xenobiotic enzymes. The animals topically treated with AsA along with topical application of CBA, restored all the impairment observed in enzyme activities. Thus, this study suggested that AsA can be useful in preventing PBA and CBA induced skin tumorigenicity.

Pesticide exposure and genetic variation in xenobiotic-metabolizing enzymes interact to induce biochemical liver damage

Metabolic activation of pesticides in the liver may result in highly reactive intermediates capable of impairing various cellular functions. Nevertheless, the knowledge about the effect of pesticide exposure on liver function is still limited. This study assessed whether exposure to pesticides elicits early biochemical changes in biomarkers of liver function and looked for potential gene-environmental interactions between pesticide exposure and polymorphisms of pesticide-metabolizing genes. A longitudinal study was conducted in farm-workers from Andalusia (South Spain), during two periods of the same crop season with different degree of pesticide exposure. Blood samples were taken for the measurement of serum and erythrocyte cholinesterase activities as well as for determining clinical chemistry parameters as biomarkers of liver function. Serum lipid levels were also measured as they may help to monitor the progress of toxic liver damage. A reduction in serum cholinesterase was associated with decreased levels of all clinical chemistry parameters studied except HDL-cholesterol. Conversely, a decreased erythrocyte cholinesterase (indicating long-term pesticide exposure) was associated with increased levels of aspartate aminotransferase and alkaline phosphatase and increased levels of triglycerides, total cholesterol and LDL-cholesterol, but reduced levels of HDL-cholesterol. Changes in liver biomarkers were particularly associated with the PON155M/192R haplotype. The obtained results therefore support the hypothesis that pesticide exposure results in subtle biochemical liver toxicity and highlight the role of genetic polymorphisms in pesticide-metabolizing enzymes as biomarkers of susceptibility for developing adverse health effects.