A new insight into the mechanism of dichlorodiphenyltrichloroethane-induced hepatotoxicity based on GSDME-mediated pyroptosis.

There have been persistent concerns about the safety risks associated with DDT residues in the environment. Studies have shown that exposure to DDT or its metabolites can cause various liver diseases. However, the mechanisms of liver toxicity haven't been well studied. In our current investigation, we observed that DDT triggers pyroptosis in human liver cells (HL-7702), representing a novel form of programmed cell death. Our results delineated DDT (0-100 µM) induced pyroptosis in HL-7702 cells, which was confirmed through morphological changes, lactate dehydrogenase (LDH) release, gasdermin E (GSDME) cleavage and Annexin-V/PI staining. Knockdown of GSDME reduced cell death and transferred the mode of cell death from pyroptosis to apoptosis. Notably, DDT exposure markedly increased reactive oxygen species (ROS) production, concurrent with c-Jun N-terminal kinase (JNK) phosphorylation. Intervention with a ROS inhibitor or JNK inhibitor SP600125 restored cell viability and hindered GSDME-mediated pyroptosis. Our results firstly demonstrate that DDT suppresses HL-7702 cells growth by inducing pyroptosis mainly through the ROS/JNK/GSDME pathway. These findings not only contribute to an in-depth understanding of DDT toxicity but also open avenues for gaining valuable insights into potential mitigation strategies and therapeutic interventions.

Acetaminophen-Induced Hepatic Necrosis: A Reminiscence.

In the early '70s, Dr B. B. Brodie, Head of the LCP, NHI, NIH, initiated a program to elucidate the mechanism of hepatic necrosis induced in rats by bromobenzene. These studies showed a crucial role for its 3,4-epoxide intermediate, known in part, to collapse to 4-bromophenol. To examine a possible contribution of this phenol to tissue toxicity, some rats were co-administered a high dose of acetaminophen to suppress phenolic clearance by glucuronidation and sulfation. Subsequent examination of liver slices showed that the acetaminophen-only control rats had extensive centrilobular liver necrosis. This article is a personal reminiscence of the events that led up to this accidental observation, how it happened, and the subsequent resolution of the underlying mechanism, including the covalent binding of NAPQI to liver protein as the initial "hit", the glutathione protective threshold, the antidotal activity of cysteine, and the existence of the "therapeutic window" for antidotal therapy. Collectively, these studies formed the basis for antidotal therapy of acetaminophen overdose patients, Significance Statement Not applicable.

Synthetic phenolic antioxidants evoked hepatoxicity in grass carp (Ctenopharyngodon idella) through modulating the ROS-PI3K/mTOR/AKT pathway: Apoptosis-autophagy crosstalk.

Synthetic phenolic antioxidants (SPAs) are an environmental concern due to their persistence nature and bioaccumulation. However, the hepatoxicity and mechanisms of SPAs in aquatic organisms remain poorly understood. In this study, grass carp were exposed to two representative SPAs (BHA and BHT) at environmentally relevant levels (0.1 µM) for 30 days. We observed that BHA and BHT exposure significantly increased the levels of serum aminotransferase (ALT) and aspartate aminotransferase (AST) in grass carp, accompanied by mild inflammatory cell infiltration and irregularity in the shape of hepatocytes. Dihydro ethylenediamine staining showed that BHA and BHT exposure resulted in elevated levels of superoxide levels, accompanied by increased antioxidant enzyme activities (T-AOC, SOD, CAT, GSH-PX) and MDA levels, which is suggestive of oxidative stress responses in the liver of grass carp. Besides, BHA and BHT could dock into the pocket of phosphatidylinositol 3-kinases (PI3K) and thereby inhibiting PI3K/mammalian target of rapamycin (mTOR)/protein kinase B (AKT) signaling cascades. Meanwhile, our results clarified that BHA and BHT could promote autophagosome production and increase the expression of key autophagy proteins, likely due to inhibition of PI3K/mTOR/AKT signaling pathway. Moreover, BHA and BHT could induce apoptotic process by upregulating the expression of Bax, Caspase3 and Caspase8 and downregulating Bcl2 expression. Notably, BHT exhibited more hepatoxicity on the indicators of the apoptosis and oxidative stress than BHA. In summary, our findings demonstrated that BHA and BHT exposure could induce liver damage induced via regulating ROS/PI3K-mediated autophagic hyperactivation, which is a crucial step in triggering hepatocyte death. This study provides novel insight into the potential mechanisms underlying liver damage caused by BHA and BHT in aquatic organisms, and offers a new theoretical basis for ecological risk assessment of SPAs.

Therapeutic effects of atorvastatin on doxorubicin-induced hepatotoxicity in rats via antioxidative damage, anti-inflammatory, and anti-lipotoxicity.

Doxorubicin (DOX), is a high efficiency anthracycline antitumor drug. However, the clinical application of DOX is limited mainly by dose-related adverse drug reactions. Currently, the therapeutic effects of Atorvastatin (ATO) on DOX-induced hepatotoxicity were studied in vivo. The results indicated that DOX impaired hepatic function, as measured by an increased levels of liver weight index and serum concentrations of aspartate transaminase and alanine transaminase, as well as alteration of hepatic histology. In addition, DOX increased the serum levles of triglyceride (TG) and nonestesterified fatty acid. ATO prevented these changes. Mechanical analysis revealed that ATO restored the changes of malondialdehyde, reactive oxygen radical species, glutathione peroxidase and manganese superoxide dismutase. Additionally, ATO inhibited the increased expression levels of nuclear factor-kappa B and interleukin 1ß, hence suppressing inflammation. Meanwhile, ATO inhibited cell apoptosis by dramatically decreasing the Bax/Bcl-2 ratio. In addition, ATO mitigated the lipidtoxicity by inhibiting the adipolysis of TG and accelerating hepatic lipid metabolism. Taken together, the results suggest ATO has therapeutic effect on DOX-induced hepatotoxicity via inhibition of oxidative damage, inflammatory and apoptosis. In addition, ATO attenuates DOX-induced hyperlipidemia via modulation of lipid metabolism.

Protective effect of dendropanoxide against cadmium-induced hepatotoxicity via anti-inflammatory activities in Sprague-Dawley rats.

Cadmium (Cd) accumulates in the body through contaminated foods or water and causes pathological damage to the liver via oxidative stress and inflammatory reactions. This study was conducted to explore the effects of dendropanoxide (DPx) on Cd-induced hepatotoxicity in rats. Sprague-Dawley (SD) rats were injected with CdCl2 (7 mg/kg body weight) intraperitoneally for 14 days for the induction of liver dysfunction. The CdCl2-exposed rats were subjected to DPx (10 mg/kg) or silymarin (50 mg/kg). The animals were euthanized after 24 h of the last CdCl2 injection and the serum biochemical parameters, lipid content, pro-inflammatory cytokine levels, apoptotic cell death and histopathology of the tissues were analyzed. Additionally, the activity of antioxidant enzymes, including superoxide dismutase (SOD) and catalase (CAT), was measured. Compared to controls, Cd-injected rats showed significantly elevated serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglycerides (TG), total cholesterol, and pro-inflammatory cytokines, and a remarkable decrease in SOD and CAT activities. Importantly, Cd-induced liver damage was drastically ameliorated by treatment with DPx or silymarin. Treatment with DPx protected the Cd-induced histopathological hepatic injury, as confirmed by the evaluation of TUNEL assay. DPx treatment significantly reduced Bax and caspase-3 expression in Cd-injected rats. Additionally, HO-1 and NRF2 expressions were significantly increased after DPx administration in the liver of Cd-injected rats. Our data indicate that DPx successfully prevents Cd-induced hepatotoxicity by emphasizing the antioxidant and anti-inflammatory effect.

Exposure to Bisphenol A Caused Hepatoxicity and Intestinal Flora Disorder in Rats.

Bisphenol A (BPA) is a globally utilized industrial chemical and is commonly used as a monomer of polycarbonate plastics and epoxy resins. Recent research reveals that BPA could cause potential adverse biological effects and liver dysfunction. However, the underlying mechanisms of BPA-induced hepatoxicity and gut dysbiosis remain unclear and deserve further study. In this study, male Sprague Dawley rats were exposed to different doses (0, 30, 90, and 270 mg/kg bw) of BPA by gavage for 30 days. The results showed that the high dose of BPA decreased superoxide dismutase (SOD), glutathione (GSH), and increased malondialdehyde (MDA) levels. Moreover, a high dose of BPA caused a significant increase in serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C), while high-density lipoprotein cholesterol (HDL-C) was significantly decreased in BPA-treated rats. The gene expression of PGC-1α and Nrf1 were decreased in the liver of high doses of BPA-administrated rats, as well as the protein levels of SIRT1, PGC-1α, Nrf2, and TFAM. However, the protein expression of IL-1ß was significantly increased in BPA-treated rats. In addition, BPA weakened the mitochondrial function of hepatocytes and promoted cell apoptosis in the liver by up-regulating the protein levels of Bax, cleaved-Caspase3, and cleaved-PARP1 while down-regulating the Bcl-2 in the liver. More importantly, a high dose of BPA caused a dramatic change in microbiota structure, as characterized at the genus level by increasing the ratio of Firmicutes to Bacteroidetes (F/B), and the relative abundance of Proteobacteria in feces, while decreasing the relative abundance of Prevotella_9 and Ruminococcaceae_UCG-014, which is positively correlated with the content of short-chain fatty acids (SCFAs). In summary, our data indicated that BPA exposure caused hepatoxicity through apoptosis and the SIRT1/PGC-1α pathway. BPA-induced intestinal flora and SCFA changes may be associated with hepatic damage. The results of this study provide a new sight for the understanding of BPA-induced hepatoxicity.

VenomPred: A Machine Learning Based Platform for Molecular Toxicity Predictions.

The use of in silico toxicity prediction methods plays an important role in the selection of lead compounds and in ADMET studies since in vitro and in vivo methods are often limited by ethics, time, budget and other resources. In this context, we present our new web tool VenomPred, a user-friendly platform for evaluating the potential mutagenic, hepatotoxic, carcinogenic and estrogenic effects of small molecules. VenomPred platform employs several in-house Machine Learning (ML) models developed with datasets derived from VEGA QSAR, a software that includes a comprehensive collection of different toxicity models and has been used as a reference for building and evaluating our ML models. The results showed that our models achieved equal or better performance than those obtained with the reference models included in VEGA QSAR. In order to improve the predictive performance of our platform, we adopted a consensus approach combining the results of different ML models, which was able to predict chemical toxicity better than the single models. This improved method was thus implemented in the VenomPred platform, a freely accessible webserver that takes the SMILES (Simplified Molecular-Input Line-Entry System) strings of the compounds as input and sends the prediction results providing a probability score about their potential toxicity.

Profiling biotoxicities of hexafluoropropylene oxide trimer acid with human embryonic stem cell-based assays.

Hexafluoropropylene oxide trimer acid (HFPO-TA), an emerging replacement of perfluorooctanoic acid (PFOA), has recently been reported to be a potential environmental contaminant. Due to the similar structure to PFOA, HFPO-TA may cause comparable adverse effects on human health. Therefore, evaluating the toxic profiles of HFPO-TA has become an urgent task. In this study, we investigated the cytotoxicity and hepatoxicity of HFPO-TA using human embryonic stem cell (hESC)-based assays. Results showed that HFPO-TA reduced hESCs' viability in a dose dependent manner, and the calculated IC50 for 24, 48 and 72 hr were 222.8, 167.4, and 80.6 µmol/L, respectively. Significant intracellular ROS accumulation and mitochondrion membrane potential reduction were detected with HFPO-TA exposure, and increased apoptotic/necrotic cells were also observed in high dose of HFPO-TA treated group. Moreover, HFPO-TA at noncytotoxic concentrations also significantly impaired the functions of induced hepatocytes by diminishing cell glycogen storage ability and deregulating specific functional genes. Transcriptome sequencing analysis identified a set of hepatic associated biological processes responding to HFPO-TA exposure. PPAR was the most significantly enriched pathway. Genes including FGA, FGB, FGG, AHSG, HRG, ITIH2, ALB were characterized as hub genes by cytoHubba plug-in. These data indicated that HFPO-TA is a potential hepatotoxicant, and may not be a safe replacement for PFOA.

Hepatic safety of repeated treatment with pyronaridine-artesunate versus artemether-lumefantrine in patients with uncomplicated malaria: a secondary analysis of the WANECAM 1 data from Bobo-Dioulasso, Burkina Faso.

BACKGROUND: The use of pyronaridine-artesunate (PA) has been associated with scarce transaminitis in patients. This analysis aimed to evaluate the hepatic safety profile of repeated treatment with PA versus artemether-lumefantrine (AL) in patients with consecutive uncomplicated malaria episodes in Bobo-Dioulasso, Burkina Faso. METHODS: This study analysed data from a clinical trial conducted from 2012 to 2015, in which participants with uncomplicated malaria were assigned to either PA or AL arms and followed up to 42 days. Subsequent malaria episodes within a 2-years follow up period were also treated with the same ACT initially allocated. Transaminases (AST/ALT), alkaline phosphatase (ALP), total and direct bilirubin were measured at days 0 (baseline), 3, 7, 28 and on some unscheduled days if required. The proportions of non-clinical hepatic adverse events (AEs) following first and repeated treatments with PA and AL were compared within study arms. The association of these AEs with retreatment in each arm was also determined using a logistic regression model. RESULTS: A total of 1379 malaria episodes were included in the intention to treat analysis with 60% of all cases occurring in the AL arm. Overall, 179 non-clinical hepatic AEs were recorded in the AL arm versus 145 in the PA arm. Elevated ALT was noted in 3.05% of treated malaria episodes, elevated AST 3.34%, elevated ALP 1.81%, and elevated total and direct bilirubin in 7.90% and 7.40% respectively. Retreated participants were less likely to experience elevated ALT and AST than first episode treated participants in both arms. One case of Hy's law condition was recorded in a first treated participant of the PA arm. Participants from the retreatment group were 76% and 84% less likely to have elevated ALT and AST, respectively, in the AL arm and 68% less likely to present elevated ALT in the PA arm. In contrast, they were almost 2 times more likely to experience elevated total bilirubin in both arms. CONCLUSIONS: Pyronaridine-artesunate and artemether-lumefantrine showed similar hepatic safety when used repeatedly in participants with uncomplicated malaria. Pyronaridine-artesunate represents therefore a suitable alternative to the current first line anti-malarial drugs in use in endemic areas. Trial registration Pan African Clinical Trials Registry. PACTR201105000286876.

Assessment of long-term functional maintenance of primary human hepatocytes to predict drug-induced hepatoxicity in vitro.

Hepatocytes are the main cell components of the liver and perform metabolic, detoxification, and endocrine functions. Functional hepatocytes are of great value in drug development, toxicity evaluation, and cell therapy for liver diseases. In recent years, an increasing number of in vitro models have been developed to screen drugs and test their toxicity. However, maintaining hepatocyte function in vitro for a long time is a serious challenge. Even freshly isolated liver cells cultured for a short time may lose function via spontaneous dedifferentiation. Thus, novel cell culture systems allowing extended hepatocyte maintenance and more predictive long-term in vitro studies are required. In this study, we developed a conditioned culture system composed of a small-molecule combination that can maintain hepatocyte morphology and functions over the long term. Two-month culture of primary human hepatocytes showed that the conditioned medium was able to stably preserve hepatic functions such as albumin and α-antitrypsin secretion, hepatic transport activity, urea synthesis, and ammonia elimination. Furthermore, this culture model can be used to assess drug-induced hepatotoxicity in vitro. In summary, our work suggests a feasible approach to maintain hepatocyte function in vitro and proposes a promising model for long-term toxicological studies and drug development.

Toxicologic effect and transcriptome analysis for short-term orally dosed enrofloxacin combined with two veterinary antimicrobials on rat liver.

Presently, toxicological assessment of multiple veterinary antimicrobials has not been performed on mammals. In this study, we assessed the short-term toxicity of enrofloxacin (E) combined with colistin (C) and quinocetone (Q). Young male rats were orally dosed drug mixtures and single drugs in 14 consecutive days, each at the dose of 20, 80, and 400 mg/(kg·BW) for environmental toxicologic study. The results showed that at the high dose treatment, the combination of E + C+Q significantly decreased body intake, lymphocytes count on rats; significantly increased the values of Alanine aminotransferase (ALT), Glutamic oxaloacetic transaminase (AST) and, cholinesterase (CHE); it also got the severest histopathological changes, where sinusoidal congestion and a large number of black particles in sinusoids were observed. This means E + C+Q in the high dose groups was able to cause significant damage to the liver. Other combinations or doses did not induce significant liver damage. Transcriptome analysis was then performed on rats in high dose group for further research. For E + C and E + Q, an amount of 375 and 480 differently expressed genes were filtered out, revealing their possible underlying effect on genomes. For E + C+Q, a weighted gene co-expression network analysis was performed and 96 hub genes were identified to reveal the specific effect induced by this combination. This study indicates that joint toxicity should be taken into consideration when involving the risk assessment of these antimicrobials.

Understanding the hepatoxicity of inorganic mercury through guts: Perturbance to gut microbiota, alteration of gut-liver axis related metabolites and damage to gut integrity.

Mercury (Hg) brings adverse effects to the environment and human beings and inorganic mercury (IHg) is a typical hepatic toxin. This work studied the impacts of IHg on gut microbes and metabolome together with its damage to liver and gut in rats through gut microbiome, metabolomics and metallomics. Sprague Dawley (SD) rats were orally exposed to 0.4 µg/mL IHg and sacrificed after 24 h. It was found that IHg perturbed greatly on the gut microbiota, such as increased pathogenic bacteria like G. bacillus. In addition, IHg also changed gut-liver axis related metabolites, which was confirmed by the secretion of a large number of inflammatory factors in both the gut and the liver. The changed gut-liver axis related metabolites correlated well to the changes of gut microbiome. In all, besides the direct deposition in liver of Hg, the perturbance to gut microbiome and alteration of gut-liver axis related metabolites by IHg also contributed to its hepatoxicity, which provides new insights about the hepatoxicity of chemicals. The strategy applied in this work may also be used to understand the hepatoxicity of other chemicals.

Hepatotoxic effects of Euphol-rich fractions from Euphorbia bivonae-Relevance to cytotoxic and anti-tumor activities.

These studies were designed to evaluate the preliminary oral toxicity profile of the crude ethanolic aerial part extract of E. bivonae in the Male albino Wistar rats and its active chemical constituents. The 24-h LD50 was determined using probit analysis method. The single dose LD50was found to be 2568.64 mg/kg bw when administrated orally in mice. Additionally, the Wistar rats were used to evaluate the subchronic toxicity of E. bivonae ethanolic extract. The serum biomarkers, lipid peroxidation and antioxidants status in liver and histopathological analysis were investigated in normal and treated groups. Subchronic toxicity studies in rats with oral doses of 50, 150, 350 and 500 mg/kg body weight showed significant increase in alanine aminotransferase, aspartate aminotransferase and total bilirubin levels. In addition, the administration of this extract significantly (p < 0.05) decreased superoxide dismutase, catalase and glutathione peroxidase and an increment in lipid peroxidation and protein carbonyls. Finally, we suggest that the three compounds of E. bivonae extract (sitosterol, euphol and lupeol) are the mainly responsible of this toxicity.

Taurine Supplementation Ameliorates Arsenic-Induced Hepatotoxicity and Oxidative Stress in Mouse.

We previously reported that taurine treatment inhibited arsenic (As)-induced apoptosis in the liver of mice. This study was designed to explore the effect of taurine on liver function and its underlying mechanism in As-exposed mice. Mice were randomly divided into 3 groups, ten mice in each group. Group 1, control group, only orally received drinking water alone. Group 2, As intoxication group, was exposed to 4 mg/L As2O3 via drinking water for 60 days. Group 3, taurine protection group, was treated with 4 mg/L As2O3 and 150 mg/kg both. Taurine administration significantly revered the increases of alanine transaminase (ALT) and aspartate transaminase (AST) activities in serum. The decrease of glutathione (GSH) was inhibited with taurine treatment in the liver of As-exposed mice. At the same time, taurine significantly inhihibited As-induced enhancement of malondialdehyde (MDA) in the liver. Here we show that taurine protective effect on liver function in As-exposed mice maybe involve lipid peroxidation.

Assessment of Preclinical Liver and Skeletal Muscle Biomarkers Following Clofibrate Administration in Wistar Rats.

Clofibrate is a known rodent hepatotoxicant classically associated with hepatocellular hypertrophy and increased serum activities of cellular alanine aminotransferase/aspartate aminotransferase (ALT/AST) in the absence of microscopic hepatocellular degeneration. At toxic dose, clofibrate induces liver and skeletal muscle injury. The objective of this study was to assess novel liver and skeletal muscle biomarkers following clofibrate administration in Wistar rats at different dose levels for 7 days. In addition to classical biomarkers, liver injury was assessed by cytokeratin 18 (CK18) cleaved form, high-mobility group box 1, arginase 1 (ARG1), microRNA 122 (miR-122), and glutamate dehydrogenase. Skeletal muscle injury was evaluated with fatty acid binding protein 3 (Fabp3) and myosin light chain 3 (Myl3). Clofibrate-induced hepatocellular hypertrophy and skeletal muscle degeneration (type I rich muscles) were noted microscopically. CK, Fabp3, and Myl3 elevations correlated to myofiber degeneration. Fabp3 and Myl3 outperformed CK for detection of myofiber degeneration of minimal severity. miR-122 and ARG1 results were significantly correlated and indicated the absence of liver toxicity at low doses of clofibrate, despite increased ALT/AST activities. Moreover, combining classical and novel biomarkers (Fabp3, Myl3, ARG1, and miR-122) can be considered a valuable strategy for differentiating increased transaminases due to liver toxicity from skeletal muscle toxicity.

Coordination Mechanism and Bio-Evidence: Reactive γ-Ketoenal Intermediated Hepatotoxicity of Psoralen and Isopsoralen Based on Computer Approach and Bioassay.

Psoralen and isopsoralen are secondary plant metabolites found in many fruits, vegetables, and medicinal herbs. Psoralen-containing plants (Psoralea corylifolia L.) have been reported to cause hepatotoxicity. Herein, we found that psoralen and isopsoralen were oxidized by CYP450s to reactive furanoepoxide or γ-ketoenal intermediates, causing a mechanism-based inhibition of CYP3A4. Furthermore, in GSH-depleted mice, the hepatotoxicity of these reactive metabolites has been demonstrated by pre-treatment with a well-known GSH synthesis inhibitor, L-buthionine-S, Rsulfoxinine (BSO). Moreover, a molecular docking simulation of the present study was undertaken to understand the coordination reaction that plays a significant role in the combination of unstable intermediates and CYP3A4. These results suggested that psoralen and isopsoralen are modest hepatotoxic agents, as their reactive metabolites could be deactivated by H2O and GSH in the liver, which partly contributes to the ingestion of psoralen-containing fruits and vegetables being safe.

The hepatoprotective activity of olive oil and Nigella sativa oil against CCl4 induced hepatotoxicity in male rats.

BACKGROUND: Liver disease is the major cause of serious health problem leading to morbidity and mortality worldwide and the problem has increased in search for hepatotherapeutic agents from plants. The present study was designed to compare the probable hepatoprotective activity of olive oil and N. sativa oil on CCl4 induced liver damage in male rats. METHODS: Forty males of a new model of albino rats (Wistar strain) (175-205 g) were divided into four groups. The 1st Group (G1) was the negative control group, the remaining rats were injected with CCl4 (1 ml/kg body weight) with equal amount of olive oil on the 1st and 4th day of every week for 4 weeks. The 2nd group (G2) was the positive control, the 3rd group (G3) and the fourth group (G4) were treated orally with N. sativa oil and olive oils using stomach tube. RESULTS: The positive control group showed an increase in hepatic enzymes, total bilirubin, creatinine, uric acid, lipid peroxide total cholesterol, triglyceride, low density lipoprotein, very low density lipoproteins, interleukin-6, and a decrease in antioxidant enzymes, high density lipoprotein cholesterol, a decrease in total protein and albumin an when compared with negative control group. Histology of the CCl4 treated group revealed inflammation and damage of liver cells. Treating the hepatotoxic rats with olive oil and N. sativa oil showed a significant improvement in all biochemical tests compared with the positive CCl4 control group. In addition, the liver tissues of olive oil treated group showed mild improvement in inflammatory infiltration and in N. sativa oil treated group showed normal hepatocytes with no evidence of inflammation. CONCLUSION: This study revealed that olive oil and N. sativa oil have a protective effect against CCl4-induced hepatotoxicity in male rats. Nigella sativa oil was more effective than olive oil.

[Exploration research on hepatotoxic constituents from Polygonum multiflorum root].

By observing the cytotoxic effects of anthraquinones on HepG2 cell and using the precision-cut liver slices technique to authenticate the cytotoxic constituents, the paper aims to explore the material basis of Polygonum multiflorum root to cause liver toxicity. Firstly, MTT method was used to detect the effect of 11 anthraquinone derivatives on HepG2 cell. Then, the clear cytotoxic ingredients were co-cultured with rat liver slices for 6h respectively, and the liver tissue homogenate was prepared. BCA method was used to determine the content of protein in the homogenate and continuous monitoring method was used to monitor the leakage of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamine amino transpeptidase (GGT) and lactate dehydrogenase (LDH). The toxic effect of these ingredients on liver tissue was tested by calculating the leakage rate of the monitored enzymes. As a result, rhein, emodin, physcion-8-O-ß-D-glucopyranoside and physcion-8-O-(6'-O-acetyl)-ß-D-glucopyranoside showed cytotoxic effects on HepG2 cell and their IC50 values were 71.07, 125.62, 242.27, 402.32 µmol•L⁻¹ respectively, but the other 7 compounds are less toxic and their IC50 values can not be calculated. The precision-cut liver slices tests showed that rhein group of 400 µmol•L⁻¹ concentration significantly increased the leakage rate of ALT, AST and LDH (P<0.01), and the rhein group of 100 µmol•L⁻¹ concentration only increased the leakage rate of LDH (P<0.05). With the increase of rhein concentration, the protein content in liver slices decreased significantly (P<0.05) with a certain range of does. Emodin group of 400 µmol•L⁻¹ concentration significantly increased the leakage rate of ALT, GGT and LDH (P<0.01). Physcion-8-O-ß-D-glucopyranoside group of 800 µmol•L⁻¹ concentration also significantly increased the leakage rate of ALT, AST and LDH (P<0.01 or P<0.05), but the group of 200 µmol•L⁻¹ concentration only significantly increased the LDH leakage (P<0.05). Along with the increase of the concentration of physcion-8-O-ß-D-glucopyranoside, the leakage rate of ALT, AST and LDH showed a trend of increase, but the protein content in liver slices was in decline. Furthermore, MTT reduction ability of liver slices significantly decreased (P<0.01) in the physcion-8-O-ß-D-glucopyranoside group of 800 µmol•L⁻¹ concentration. The results suggested that rhein, emodin and physcion-8-O-ß-D-glucopyranoside at high concentrations (≥400 µmol•L⁻¹) can produce some damage to the liver tissue. However, the exposure levels of these constituents are very low, so to reach the toxic concentration (400 µmol•L⁻¹ or 800 µmol•L⁻¹) an adult of 65 kg body weight will need at least a single oral 4 898 g, 339 g and 5 581 g of P.multiflorum root respectively, which is far from the statutory dose of crude P. multiflorum root (3-6 g) or its processed product (6-12 g). Therefore, the conclusion that anthraquinones are the prime constituents of the hepatotoxicity of P. multiflorum root are still not be proved.

Co-administration of N-Acetylcysteine and Acetaminophen Efficiently Blocks Acetaminophen Toxicity.

Preclinical Research Although acetaminophen (APAP) is an effective analgesic and anti-pyretic, APAP overdose is the most frequent cause of serious, often lethal, drug-induced hepatotoxicity. Administration of N-acetyl cysteine (NAC) within 8 hours of APAP overdose effectively mitigates APAP-induced hepatotoxicity. Thus, preventing APAP toxicity before it occurs by formulating APAP with NAC is logical and, as we show here in a mouse model, is effective in preventing APAP toxicity. Thus, toxic oral APAP doses sufficient to cause severe widespread liver damage do not cause significant damage when administered concurrently with equal amounts of NAC, that is, in the NAC-APAP treated animals, hepatic transaminases increase only marginally and liver architecture remains fully intact. Thus, we conclude that concomitant oral dosing with APAP and NAC can provide a convenient and effective way of preventing toxicity associated with large dosage of APAP. From a public health perspective, these findings support the concept that a co-formulation of APAP plus NAC is a viable over-the-counter (OTC) alternative to the current practice of providing APAP OTC and treating APAP toxicity if/when it occurs. In essence, our findings indicate that replacing the current OTC APAP with a safe and functional APAP/NAC formulation could prevent the accidental and intentional APAP toxicity that occurs today.