Diagnostic and predictive performance and standardized threshold of traditional biomarkers for drug-induced liver injury in rats

Mancozeb-induced hepatotoxicity: protective role of curcumin in rat animal model

Background

Mancozeb-a widely used fungicide in the agricultural sector-is believed to cause toxicity by increasing oxidative stress. This work investigated the efficacy of curcumin in protecting mancozeb-induced hepatotoxicity.

Materials and Methods

Mature Wistar rats were assigned into 4 equal groups: control, mancozeb (30 mg/kg/day, ip), curcumin (100 mg/kg/day, po), and mancozeb+curcumin. The experiment lasted for 10 days.

Results

Our results reported that mancozeb elevated aspartate transaminase, alanine transaminase, alkaline phosphatase, lactate dehydrogenase, gamma glutamyltranspeptidase enzyme activities, and total bilirubin level in plasma; and decreased total protein and albumin levels, compared with the control group (P < 0.05-0.001). Hepatic tissue levels of malondialdehyde, and advanced oxidation protein products were significantly increased; whereas activities of superoxide dismutase, catalase, glutathione peroxidase, as well as levels of reduced glutathione, vitamin C, and total protein were reduced (P < 0.05-0.001). Histopathological examination showed marked histological changes. Co-treatment with curcumin improved the antioxidant activity; reversed oxidative stress and biochemical changes; and restored most of the liver histo-morphological alterations; thus, attenuating the hepatic toxicities induced by mancozeb.

Conclusion

These results indicated that curcumin could protect against detrimental hepatic effects induced by mancozeb.

Hepatotoxicity of Short Term Exposure to Mancozeb Fungicide in Male Wistar Rats

Mancozeb is a dithiocarbamate fungicide used effectively to protect plant products against fungi. The hepatic effects of short term exposure to mancozeb in adult male Wistar rats were investigated in the present study. Twenty-four animals were divided into four equal groups. Two groups were administered mancozeb (60 mg/kg body weight as single dose or 30 mg/kg body weight daily for 10 days, intraperitoneally), and the others, which served as control groups, received normal saline. Liver biochemical parameters in plasma were measured using standard methods. Liver homogenates were analysed for oxidative stress biomarkers and liver histopathology was studied. Single dose and 10 days exposures of mancozeb caused elevation in the activities of Alanine Transaminase (ALT), Aspartate Transaminase (AST), Alkaline Phosphatase (ALP), Lactate Dehydrogenase (LDH), and Gamma Glutamyl Transpeptidase (GGT) in plasma (p<0.05-0.001) compared with control. Mancozeb also caused elevation in the plasma level of total bilirubin, and reductions in albumin, total protein, and conjugated bilirubin. In addition, Malondialdehyde (MDA) and Advanced Oxidation Protein Product (AOPP) levels were increased in hepatic tissues (p<0.001) of all mancozeb exposed rats. Furthermore, hepatic levels of protein, reduced Glutathione (GSH) and vitamin C were decreased (p<0.01), together with the activities of Superoxide Dismutase (SOD), catalase, and Glutathione Peroxidase (GPx) enzymes (p<0.01-0.001). Histological analysis showed severe histopathological changes in mancozeb exposed rats. The results demonstrated that single dose intraperitoneal exposure of mancozeb (60 mg/kg body weight) or short term (10 days) daily exposure at 30 mg/kg body weight is capable of causing hepatotoxic effects in rats.

Foliar application of zinc and selenium alleviates cadmium and lead toxicity of water spinach - Bioavailability/cytotoxicity study with human cell lines

The present study investigated the effects of foliar application of zinc (Zn) and selenium (Se) on bioavailability of Zn and Se and toxicity of cadmium (Cd) and lead (Pb) to different water spinach ecotypes (LA and HA) grown in slightly (XZ) or moderately (LJY) contaminated fields via in vitro digestion combined with Caco-2/HL-7702 cell model. The obtained results revealed that foliar application of Zn and Se promoted yield, increased total, bioaccessible and bioavailable fractions of Zn and Se in plants, indicating that foliar application is a feasible way of biofortification. Although there was no significant effect on liver cell proliferation (MTT), membrane stability (LDH) and hepatocyte enzyme (ALT and AST) activities, the obvious ecotype and soil dependent fluctuations of lipid peroxidation (MDA) and antioxidant enzyme (SOD, POD and CAT) activities in serum highly suggest that the low accumulator and clean field should be used in agricultural production rather than the high accumulator and contaminated farmland. Moreover, foliar application of Zn and Se improved nutritional quality of all water spinach genotypes in both fields, including increased Fe, vitamin C, cellulose and chlorophyll, maintained concentrations of potassium (K), manganese (Mn), copper (Cu), protein, and nitrate. These results demonstrate that this agricultural management practice may prove to be an effective approach for minimizing health risk and alleviating "hidden hunger" in the developing countries.

Tetracycline uptake by pak choi grown on contaminated soils and its toxicity in human liver cell line HL-7702

Tetracycline (TC) can enter the human body via the soil-vegetable-human food chain; therefore, it is necessary to understand the toxicity of TC to humans through vegetables grown on contaminated soils. The present study combined an enzyme-linked immunosorbent assay method and an HL-7702 cell model and assessed the bioavailability and toxicity of TC from pak choi (Brassica campestris L. ssp. chinensis) grown on TC-contaminated soils. The results showed that the degradation rate of TC in black soil was significantly higher than that in purplish clay, while the results for TC uptake in pak choi were opposite. The bioaccessibility of TC was found to be higher in pak choi grown on purplish clay (5.67-7.59%) than in that grown on black soil (5.22-6.77%). It is suggested that soil properties contribute to the uptake of TC by pak choi. More fertile soil contained lower TC concentrations and thus mediated lower TC toxicity to humans. It may seem comforting that TC concentrations in the edible parts of pak choi are often found to be below safe limits. However, the TC diagnosis method showed that even moderate increases in TC concentrations in pak choi may induce oxidative stress, liver injury, mitochondrial cristae and rough endoplasmic reticulum swelling, and early apoptosis in liver cells HL-7702. The pak choi grown in purplish clay showed higher TC cytotoxicity than that grown in black soil. The TC cytotoxicity of raw pak choi was found to be higher than that of cooked pak choi. These results provide direct evidence of effective ways to prevent TC toxicity in humans.

Predictors of poor outcomes in 488 patients with herb-induced liver injury

BACKGROUND/AIMS

Herb-induced liver injury (HILI) can lead to chronic liver injury, liver transplantation, or even death. This study aimed to identify the predictors of poor HILI outcomes, especially chronic HILI.

MATERIALS AND METHODS

Clinical data of 488 patients with HILI were retrospectively analyzed from a Chinese center between January 2010 and January 2014. Logistic regression and C-statistic were used to identify risk factors and prognostic models for HILI outcomes.

RESULTS

In all patients, 69 (14.1%) developed chronic HILI, and 20 (4.1%) died due to liver injury or underwent liver transplantation. To predict the fatal HILI prognosis, the model for end-stage liver disease (MELD) with a C-statistic of 0.981 (95%CI 0.968-0.995) was better than Hy's law (C-statistic 0.569; 95%CI 0.449-0.689). The latency, course of peak alanine aminotransferase decreasing >50% after discontinuation of herb application, peak triglyceride value, and platelet count at liver injury onset were identified as independent risk factors for chronicity with the adjusted odds ratios of 1.268 (95% confidence interval [CI] 1.034-1.554), 2.303 (95%CI 1.588-3.340), 0.580 (95%CI 0.343-0.978), and 0.183 (95%CI 0.091-0.368), respectively. A prognostic model for chronic HILI based on these four factors yielded the best prediction with a C-statistic of 0.812 (95%CI 0.755-0.868), compared with MELD (C-statistic 0.506; 95%CI 0.431-0.581) and Hy's law (C-statistic 0.418; 95%CI 0.343-0.492).

CONCLUSION

Model for end-stage liver disease can be used to predict the fatal prognosis of HILI. A long latency, slow recovery, and low triglyceride value and platelet counts are important determinants for chronic HILI.

A New Structure-Activity Relationship (SAR) Model for Predicting Drug-Induced Liver Injury, Based on Statistical and Expert-Based Structural Alerts

The prompt identification of chemical molecules with potential effects on liver may help in drug discovery and in raising the levels of protection for human health. Besides in vitro approaches, computational methods in toxicology are drawing attention. We built a structure-activity relationship (SAR) model for evaluating hepatotoxicity. After compiling a data set of 950 compounds using data from the literature, we randomly split it into training (80%) and test sets (20%). We also compiled an external validation set (101 compounds) for evaluating the performance of the model. To extract structural alerts (SAs) related to hepatotoxicity and non-hepatotoxicity we used SARpy, a statistical application that automatically identifies and extracts chemical fragments related to a specific activity. We also applied the chemical grouping approach for manually identifying other SAs. We calculated accuracy, specificity, sensitivity and Matthews correlation coefficient (MCC) on the training, test and external validation sets. Considering the complexity of the endpoint, the model performed well. In the training, test and external validation sets the accuracy was respectively 81, 63, and 68%, specificity 89, 33, and 33%, sensitivity 93, 88, and 80% and MCC 0.63, 0.27, and 0.13. Since it is preferable to overestimate hepatotoxicity rather than not to recognize unsafe compounds, the model's architecture followed a conservative approach. As it was built using human data, it might be applied without any need for extrapolation from other species. This model will be freely available in the VEGA platform.

Comparison of the Treatment Efficiency of Bone Marrow-Derived Mesenchymal Stem Cell Transplantation via Tail and Portal Veins in CCl4-Induced Mouse Liver Fibrosis

Because of self-renewal, strong proliferation in vitro, abundant sources for isolation, and a high differentiation capacity, mesenchymal stem cells are suggested to be potentially therapeutic for liver fibrosis/cirrhosis. In this study, we evaluated the treatment effects of mouse bone marrow-derived mesenchymal stem cells (BM-MSCs) on mouse liver cirrhosis induced by carbon tetrachloride. Portal and tail vein transplantations were examined to evaluate the effects of different injection routes on the liver cirrhosis model at 21 days after transplantation. BM-MSCs transplantation reduced aspartate aminotransferase/alanine aminotransferase levels at 21 days after injection. Furthermore, BM-MSCs induced positive changes in serum bilirubin and albumin and downregulated expression of integrins (600- to 7000-fold), transforming growth factor, and procollagen-α1 compared with the control group. Interestingly, both injection routes ameliorated inflammation and liver cirrhosis scores. All mice in treatment groups had reduced inflammation scores and no cirrhosis. In conclusion, transplantation of BM-MSCs via tail or portal veins ameliorates liver cirrhosis in mice. Notably, there were no differences in treatment effects between tail and portal vein administrations. In consideration of safety, we suggest transfusion of bone marrow-derived mesenchymal stem cells via a peripheral vein as a potential method for liver fibrosis treatment.