Animal models of drug-induced liver injury

Synthesis and preclinical testing of a selective beta-subtype agonist of thyroid hormone receptor ZTA-261

BACKGROUND

Thyroid hormones (TH) regulate the basal metabolic rate through their receptors THRα and THRβ. TH activates lipid metabolism via THRβ, however, an excess amount of TH can lead to tachycardia, bone loss, and muscle wasting through THRα. In recent years, TH analogs that selectively bind to THRβ have gained attention as new agents for treating dyslipidemia and obesity, which continue to pose major challenges to public health worldwide.

METHODS

We developed a TH analog, ZTA-261, by modifying the existing THRβ-selective agonists GC-1 and GC-24. To determine the THRβ-selectivity of ZTA-261, an in vitro radiolabeled TH displacement assay was conducted. ZTA-261 was intraperitoneally injected into a mouse model of high-fat diet-induced obesity, and its effectiveness in reducing body weight and visceral fat, and improving lipid metabolism was assessed. In addition, its toxicity in the liver, heart, and bone was evaluated.

RESULTS

ZTA-261 is more selective towards THRβ than GC-1. Although ZTA-261 is less effective in reducing body weight and visceral fat than GC-1, it is as effective as GC-1 in reducing the levels of serum and liver lipids. These effects are mediated by the same pathway as that of T3, a natural TH, as evidenced by similar changes in the expression of TH-induced and lipid metabolism-related genes. The bone, cardiac, and hepatotoxicity of ZTA-261 are significantly lower than those of GC-1.

CONCLUSIONS

ZTA-261, a highly selective and less toxic THRβ agonist, has the potential to be used as a drug for treating diseases related to lipid metabolism.

Isolation and characterization of a hepatoprotective polysaccharide from Lonicera caerulea L. var. edulis Turcz. ex Herd. fruit against APAP-induced acute liver injury mice

The structure and bioactivities of a novel polysaccharide from Lonicera caerulea L. var. edulis Turcz. ex Herd. fruit (THP-3) were investigated. The crude polysaccharides of Turcz. ex Herd. (THP) were extracted by hot water extraction. After purification, the chemical structure of polysaccharides was identified. Then, a mouse model of acute drug-induced liver injury was constructed using 4-acetamidophenol (APAP) and pretreated with THP. The number-average molecular weight of THP-3 was 48.89 kDa and the mass average molar mass was 97.87 kDa. THP-3 was mainly composed of arabinose (42.54 %), glucose (27.62 %), galacturonic acid and galactose (29.84 %). The main linkage types of THP-3 were 1-linked Araf, 1,4-linked Glcp, and 1,3,6-linked Galp. In addition, after THP treatment, serum Alanine aminotransferase (ALT), Aspartate aminotransferase (AST) and γ-glutamyl transpeptidase (γGT) in AILI mice were successfully down-regulated. The results showed that THP could prevent the characteristic morphological changes of hepatic lobular injury and lipid depletion caused by APAP, reduced the level of oxidative damage in mice, increased the expression of APAP-induced hypolipidemia and related inflammatory indicators, and improved the detoxification function of liver. In general, the newly extracted THP polysaccharide has a good liver protection effect and is an ideal natural medicine for the treatment of liver diseases.

The Discovery of Gut Microbial Metabolites as Modulators of Host Susceptibility to Acetaminophen-Induced Hepatotoxicity

The mammalian gut microbiota plays diverse and essential roles in modulating host physiology. Key mediators determining the outcome of the microbiota-host interactions are the small molecule metabolites produced by the gut microbiota. The liver is a major organ exposed to gut microbial metabolites, and it serves as the nexus for maintaining healthy interactions between the gut microbiota and the host. At the same time, the liver is the primary target of potentially harmful gut microbial metabolites. In this review, we provide an up-to-date list of gut microbial metabolites that have been identified to either increase or decrease host susceptibility to acetaminophen (APAP)-induced liver injury. The signaling pathways and molecular factors involved in the progression of APAP-induced hepatotoxicity are well-established, and we propose that the mouse model of APAP-induced hepatotoxicity serves as a model system for uncovering gut microbial metabolites with previously unknown functions. Furthermore, we envision that gut microbial metabolites identified to alter APAP-induced hepatotoxicity likely have broader implications in other liver diseases. SIGNIFICANCE STATEMENT: This review provides an overview of the role of the gut microbiota in modulating the host susceptibility to acetaminophen (APAP)-induced liver injury. It focuses on the roles of gut bacterial small molecule metabolites as mediators of the interaction between the gut microbiota and the liver. It also illustrates the utility of APAP-induced liver injury as a model to identify gut microbial metabolites with biological function.

Hepatoprotective effects of fruits pulp, seed, and peel against chemical-induced toxicity: Insights from in vivo studies

The liver is a vital organ in human physiology positioned in the upper right quadrant of the peritoneal cavity, which plats a critical role in metabolic processes, detoxification of various substances and overall homeostasis. Along with these critical functions, hepatic diseases impose as significant global health threat. Liver illness is the cause of two million fatalities every year, or 4% of all deaths. Traditionally, healthcare providers have prescribed antibacterial and antiviral medications to address liver illness. Nephrotoxicity is a frequently observed negative reaction to drugs, with the majority of such events happening in individuals who have advanced cirrhosis. Thus, recognizing this gap, there is a dire need of exploration of pharmaceutical alterative for hepatic diseases, with special focus on their efficacy and reduced toxicity. Fruits have long been known to therapeutic impact on human health, thus exploration of fruits components namely pulp, seeds and peels containing phytochemicals have emerged as a promising avenue for hepatoprotective interventions. Thus, review comprehends the information about worldwide burden of chemical induced toxicity and injuries as well as highlight the on-going challenges in hepatic disease management. It also shed light on the valuable contributions fruit parts and their phytocompounds obtained from different components of fruits. Fruit pulp, especially when rich in flavonoids, has demonstrated significant potential in animal model studies. It has been observed to enhance the activity of antioxidant enzymes and reduce the expression of pro-inflammatory markers. The methanolic and ethanolic extracts have demonstrated the most favorable outcomes. Further, this review also discusses about the safety assessments of fruits extracts for their utilization as hepatoprotective agents.

Ganoderma lucidum Polysaccharides Ameliorate Acetaminophen-Induced Acute Liver Injury by Inhibiting Oxidative Stress and Apoptosis along the Nrf2 Pathway

The excessive employment of acetaminophen (APAP) is capable of generating oxidative stress and apoptosis, which ultimately result in acute liver injury (ALI). Ganoderma lucidum polysaccharides (GLPs) exhibit hepatoprotective activity, yet the protective impact and potential mechanism of GLPs in relation to APAP-induced ALI remain ambiguous. The intention of this research was to scrutinize the effect of GLPs on APAP-induced ALI and to shed light on their potential mechanism. The results demonstrated that GLPs were capable of notably alleviating the oxidative stress triggered by APAP, as shown through a significant drop in the liver index, the activities of serum ALT and AST, and the amounts of ROS and MDA in liver tissue, along with an increase in the levels of SOD, GSH, and GSH-Px. Within these, the hepatoprotective activity at the high dose was the most conspicuous, and its therapeutic efficacy surpassed that of the positive drug (bifendate). The results of histopathological staining (HE) and apoptosis staining (TUNEL) indicated that GLPs could remarkably inhibit the necrosis of hepatocytes, the permeation of inflammatory cells, and the occurrence of apoptosis induced by APAP. Moreover, Western blot analysis manifested that GLPs enhanced the manifestation of Nrf2 and its subsequent HO-1, GCLC, and NQO1 proteins within the Nrf2 pathway. The results of qPCR also indicated that GLPs augmented the expression of antioxidant genes Nrf2, HO-1, GCLC, and NQO1. The results reveal that GLPs are able to set off the Nrf2 signaling path and attenuate ALI-related oxidative stress and apoptosis, which is a potential natural medicine for the therapy of APAP-induced liver injury.

Ethanol Extract of the Microalga Phaeodactylum tricornutum Shows Hepatoprotective Effects against Acetaminophen-Induced Acute Liver Injury in Mice

Acute liver failure is an infrequent yet fatal condition marked by rapid liver function decline, leading to abnormalities in blood clotting and cognitive impairment among individuals without prior liver ailments. The primary reasons for liver failure are infection with hepatitis virus or overdose of certain medicines, such as acetaminophen. Phaeodactylum tricornutum (PT), a type of microalgae known as a diatom species, has been reported to contain an active ingredient with anti-inflammatory and anti-obesity effects. In this study, we evaluated the preventive and therapeutic activities of PT extract in acute liver failure. To achieve our purpose, we used two different acute liver failure models: acetaminophen- and D-GalN/LPS-induced acute liver failure. PT extract showed protective activity against acetaminophen-induced acute liver failure through attenuation of the inflammatory response. However, we failed to demonstrate the protective effects of PT against acute liver injury in the D-GalN/LPS model. Although the PT extract did not show protective activity against two different acute liver failure animal models, this study clearly demonstrates the importance of considering the differences among animal models when selecting an acute liver failure model for evaluation.

Susceptibility to Hepatotoxic Drug-Induced Liver Injury Increased After Traumatic Brain Injury in Mice

The early stages of brain injury can induce acute liver injury, which can be recovered in the short term. Continued medication treatment during hospitalization for brain injury alleviates the prognosis and contributes to a high incidence of drug-induced liver injury (DILI). We hypothesize that there is an interaction between changes in the hepatic environment after brain injury and liver injury produced by intensive drug administration, leading to an upregulation of the organism's sensitivity to DILI. In this study, mice models of TBI were established by controlled cortical impact (CCI) and models of DILI were constructed by acetaminophen (APAP). All mice were divided into four groups: Sham, TBI, APAP, and TBI+APAP, and related liver injury indicators in liver and serum were detected by Western blot, Quantitative real-time PCR (qRT-PCR), and immunohistochemical staining. The results suggested that liver injury induced in the early stages of brain injury recovered in 3 days, but this state could still significantly aggravate DILI, represented by higher liver enzymes (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]), oxidative stress (increase in malondialdehyde [MDA] concentration and deregulation of glutathione [GSH] and superoxide dismutase [SOD] activities), inflammatory response (activation of the HMGB1/TLR4/NF-κB signaling pathway, and increased messenger RNA [mRNA] and protein levels of pro-inflammatory cytokines including tumor necrosis factor alpha [TNF-α], interleukin [IL]-6, and IL-1β), and apoptosis (TUNEL assay, upregulation of Bax protein and deregulation of Bcl-2 protein). In summary, our results suggested that TBI is a potential susceptibility factor for DILI and exacerbates DILI.

Research progress on rat model of drug-induced liver injury established by nonsteroidal anti-inflammatory drug (celecoxib) and royal jelly ameliorative effect

OBJECTIVES

NSAIDs, like celecoxib, are widely used to treat pain, fever, and inflammation, with celecoxib being particularly effective in managing arthritis symptoms and acute or chronic pain especially with its favorable gastrointestinal tolerability. The study aimed at exploring the effect of chronic administration of celecoxib on hepatic tissues in male albino rats. It also examined the royal jelly celecoxib interplay.

METHODS

50 male albino rats in 5 equal groups; Group 1: received no drug. Group 2: received celecoxib (50 mg/kg/day, orally), for 30 successive days. Group 3: received celecoxib plus royal jelly (300 mg/kg/day, orally) for 30 successive days. Group 4: received celecoxib, for 30 days, then were left untreated for another 30 days. Group 5: received celecoxib plus royal jelly for 30 days, then were left untreated for another 30 days.

RESULTS

Chronic celecoxib administration caused hepatotoxicity in male albino rats, with ameliorative effect of royal jelly. Celecoxib discontinuation significantly diminished the celecoxib-induced toxicity, and normal liver enzymes and serum protein levels were regained in the case of dual medications (celecoxib+RJ) discontinuation.

CONCLUSIONS

Long-term celecoxib administration caused hepatotoxicity, with ameliorative effects of royal jelly against celecoxib-induced oxidative and apoptotic stress. In addition, it could be concluded that royal jelly may prove a useful adjunct in patients being prescribed celecoxib.

Fibrinolysis-Mediated Pathways in Acute Liver Injury

Acute liver injury (ALI), that is, the development of reduced liver function in patients without preexisting liver disease, can result from a wide range of causes, such as viral or bacterial infection, autoimmune disease, or adverse reaction to prescription and over-the-counter medications. ALI patients present with a complex coagulopathy, characterized by both hypercoagulable and hypocoagulable features. Similarly, ALI patients display a profound dysregulation of the fibrinolytic system with the vast majority of patients presenting with a hypofibrinolytic phenotype. Decades of research in experimental acute liver injury in mice suggest that fibrinolytic proteins, including plasmin(ogen), plasminogen activators, fibrinolysis inhibitors, and fibrin(ogen), can contribute to initial hepatotoxicity and/or stimulate liver repair. This review summarizes major experimental findings regarding the role of fibrinolytic factors in ALI from the last approximately 30 years and identifies unanswered questions, as well as highlighting areas for future research.

Advanced three-dimensional in vitro liver models to study the activity of anticancer drugs

The liver is one of the most important organs in the human body. It performs many important functions, including being responsible for the metabolism of most drugs, which is often associated with its drug-induced damage. Currently, there are no ideal pharmacological models that would allow the evaluation of the effect of newly tested drugs on the liver in preclinical studies. Moreover, the influence of hepatic metabolism on the effectiveness of the tested drugs is rarely evaluated. Therefore, in this work we present an advanced model of the liver, which reflects most of the morphologically and metabolically important features of the liver in vivo, namely: three-dimensionality, cellular composition, presence of extracellular matrix, distribution of individual cell types in the structure of the liver model, high urea and albumin synthesis efficiency, high cytochrome p450 activity. In addition, the work, based on the example of commonly used anticancer drugs, shows how important it is to take into account hepatic metabolism in the effective assessment of their impact on the target organ, in this case cancer. In our research, we have shown that the most similar to liver in vivo are 3D cellular aggregates composed of three important liver cells, namely hepatocytes (HepG2), hepatic stellate cells (HSCs), and hepatic sinusoidal endothelial cells (HSECs). Moreover, we showed that the cells in 3D aggregate structure need time (cell-cell interactions) to improve proper liver characteristic. The triculture model additionally showed the greatest ability to metabolize selected anticancer drugs.

Natural Products That Protect Against Acetaminophen Hepatotoxicity: A Call for Increased Rigor in Preclinical Studies of Dietary Supplements

Acetaminophen (APAP) overdose is one of the most common causes of acute liver injury. The current standard-of-care treatment for APAP hepatotoxicity, N-acetyl-l-cysteine, is highly effective when administered early after overdose, but loses efficacy in later-presenting patients. As a result, there is interest in the identification of new treatments for APAP overdose patients. Natural products are a promising source of new treatments because many are purported to have hepatoprotective effects. In fact, a great deal of research has been done to identify natural products that can protect against APAP-induced liver injury. However, serious concerns have been raised about the rigor and human relevance of these studies. Here, we systematically reviewed the APAP-natural product literature from 2013 to 2023 to determine the veracity of these concerns and the scope of the potential problem. The results substantiate the concerns that have been previously raised and point to concrete steps that can be taken to improve APAP-natural product research.

Comparative analysis of gene expression between mice and humans in acetaminophen-induced liver injury by integrating bioinformatics analysis

OBJECTIVE

Mice are routinely utilized as animal models of drug-induced liver injury (DILI), however, there are significant differences in the pathogenesis between mice and humans. This study aimed to compare gene expression between humans and mice in acetaminophen (APAP)-induced liver injury (AILI), and investigate the similarities and differences in biological processes between the two species.

METHODS

A pair of public datasets (GSE218879 and GSE120652) obtained from GEO were analyzed using "Limma" package in R language, and differentially expressed genes (DEGs) were identified, including co-expressed DEGs (co-DEGs) and specific-expressed DEGS (specific-DEGs). Analysis of Gene Set Enrichment Analysis (GSEA), Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were performed analyses for specific-DEGs and co-DEGs. The co-DEGs were also used to construct transcription factor (TF)-gene network, gene-miRNA interactions network and protein-protein interaction (PPI) network for analyzing hub genes.

RESULTS

Mouse samples contained 1052 up-regulated genes and 1064 down-regulated genes, while human samples contained 1156 up-regulated genes and 1557 down-regulated genes. After taking the intersection between the DEGs, only 154 co-down-regulated and 89 co-up-regulated DEGs were identified, with a proportion of less than 10%. It was suggested that significant differences in gene expression between mice and humans in drug-induced liver injury. Mouse-specific-DEGs predominantly engaged in processes related to apoptosis and endoplasmic reticulum stress, while human-specific-DEGs were concentrated around catabolic process. Analysis of co-regulated genes reveals showed that they were mainly enriched in biosynthetic and metabolism-related processes. Then a PPI network which contains 189 nodes and 380 edges was constructed from the co-DEGs and two modules were obtained by Mcode. We screened out 10 hub genes by three algorithms of Degree, MCC and MNC, including CYP7A1, LSS, SREBF1, FASN, CD44, SPP1, ITGAV, ANXA5, LGALS3 and PDGFRA. Besides, TFs such as FOXC1, HINFP, NFKB1, miRNAs like mir-744-5p, mir-335-5p, mir-149-3p, mir-218-5p, mir-10a-5p may be the key regulatory factors of hub genes.

CONCLUSIONS

The DEGs of AILI mice models and those of patients were compared, and common biological processes were identified. The signaling pathways and hub genes in co-expression were identified between mice and humans through a series of bioinformatics analyses, which may be more valuable to reveal molecular mechanisms of AILI.

Dietary Supplement-Induced Hepatotoxicity: A Clinical Perspective

The consumption of dietary supplements (DS) has resulted in a significant and escalating number of cases involving liver injury. It is crucial for clinicians and consumers to be well informed about the adverse effects of such products, leading to their discontinuation and timely reporting of any harmful cases. This article delves into the clinical perspective of DS-related hepatotoxicity, highlighting key concepts such as a systematic diagnostic approach. The discussion extends to notable examples of both currently popular and potential future dietary supplements, such as garcinia cambogia, turmeric, and ashwagandha, accompanied by an overview of recent findings. Causality assessment tools play a crucial role in establishing a connection between these products and instances of liver injury, with consideration of the advantages and disadvantages associated with their use. Fostering a comprehensive understanding of regulatory standards, coupled with a solid foundation of knowledge of DS, will prove instrumental in preventing DS-related hepatotoxicity. Achieving this goal requires collaborative efforts from both consumers and clinicians.

Investigation of the usefulness of liver-specific deconvolution method by establishing a liver benchmark dataset

Immune responses in the liver are related to the development and progression of liver failure, and precise prediction of their behavior is important. Deconvolution is a methodology for estimating the immune cell proportions from the transcriptome, and it is mainly applied to blood-derived samples and tumor tissues. However, the influence of tissue-specific modeling on the estimation results has rarely been investigated. Here, we constructed a system to evaluate the performance of the deconvolution method on liver transcriptome data. We prepared seven mouse liver injury models using small-molecule compounds and established a benchmark dataset with corresponding liver bulk RNA-Seq and immune cell proportions. RNA-Seq expression for nine leukocyte subsets and four liver-associated cell types were obtained from the Gene Expression Omnibus to provide a reference. We found that the combination of reference cell sets affects the estimation results of reference-based deconvolution methods and established a liver-specific deconvolution by optimizing the reference cell set for each cell to be estimated. We applied this model to independent datasets and showed that liver-specific modeling is highly extrapolatable. We expect that this approach will enable sophisticated estimation from rich tissue data accumulated in public databases and to obtain information on aggregated immune cell trafficking.

Nobiletin from citrus peel: a promising therapeutic agent for liver disease-pharmacological characteristics, mechanisms, and potential applications

Nobiletin (NOB) is a flavonoid derived from citrus peel that has potential as an alternative treatment for liver disease. Liver disease is a primary health concern globally, and there is an urgent need for effective drugs. This review summarizes the pharmacological characteristics of NOB and current in vitro and in vivo studies investigating the preventive and therapeutic effects of NOB on liver diseases and its potential mechanisms. The findings suggest that NOB has promising therapeutic potential in liver diseases. It improves liver function, reduces inflammation and oxidative stress, remodels gut microflora, ameliorates hepatocellular necrosis, steatosis, and insulin resistance, and modulates biorhythms. Nuclear factor erythroid 2-related factor 2 (Nrf2), nuclear transcription factor kappa (NF-κB), AMP-activated protein kinase (AMPK), peroxisome proliferator-activated receptor α(PPAR-α), extracellular signal-regulated kinase (ERK), protein kinase B (AKT), toll-like receptor 4 (TLR4) and transcription factor EB (TFEB) signaling pathways are important molecular targets for NOB to ameliorate liver diseases. In conclusion, NOB may be a promising drug candidate for treating liver disease and can accelerate its application from the laboratory to the clinic. However, more high-quality clinical trials are required to validate its efficacy and identify its molecular mechanisms and targets.

Research progress on rodent models and its mechanisms of liver injury

The liver is the most important organ for biological transformation in the body and is crucial for maintaining the body's vital activities. Liver injury is a serious pathological condition that is commonly found in many liver diseases. It has a high incidence rate, is difficult to cure, and is prone to recurrence. Liver injury can cause serious harm to the body, ranging from mild to severe fatty liver disease. If the condition continues to worsen, it can lead to liver fibrosis and cirrhosis, ultimately resulting in liver failure or liver cancer, which can seriously endanger human life and health. Therefore, establishing an rodent model that mimics the pathogenesis and severity of clinical liver injury is of great significance for better understanding the pathogenesis of liver injury patients and developing more effective clinical treatment methods. The author of this article summarizes common chemical liver injury models, immune liver injury models, alcoholic liver injury models, drug-induced liver injury models, and systematically elaborates on the modeling methods, mechanisms of action, pathways of action, and advantages or disadvantages of each type of model. The aim of this study is to establish reliable rodent models for researchers to use in exploring anti-liver injury and hepatoprotective drugs. By creating more accurate theoretical frameworks, we hope to provide new insights into the treatment of clinical liver injury diseases.

Veronica persica ameliorates acetaminophen-induced murine hepatotoxicity via attenuating oxidative stress and inflammation

Excess acetaminophen (APAP) commonly causes severe acute liver injury (ALI), characterized by oxidative stress, pro-inflammatory responses, and hepatocyte damage. Veronica persica (VP) is a traditional medicine with antioxidant and anti-inflammatory properties. There is a paucity of information on its medicinal value, especially its potential mechanisms for alleviating ALI. This study aimed to clarify the ameliorative effects and intracellular mechanisms of VP on APAP-induced ALI via attenuating oxidative stress and inflammation. Mice were given VP for 7 days before exposure to APAP (300 mg/kg). The HPLC and radical scavenging assay found that VP contains 12 phenolic acids and 6 flavonoids, as well as show robust antioxidant capacity. In the APAP-induced ALI model, pre-treatment with VP significantly reduces APAP-induced hepatotoxicity by observing improved hepatocyte pathological injury and further confirmed by serum biochemical indicator. Also, the reduction of TUNEL-positive regions and the regulation of Bcl-2-associated X protein indicated that VP attenuates hepatocytotoxicity. Moreover, VP pre-intervention inhibits the formation of liver pro-inflammatory cytokines, the expression of inflammatory response genes, and increases in myeloperoxidase (MPO) in APAP-exposed mice. The elevated reduced glutathione (GSH) levels and decreased oxidative stress markers indicate that VP reduces APAP-promoted oxidative stress. Further study revealed that VP inhibited the phosphorylation of NF-κB/STAT3 cascade, blocked ERK and JNK phosphorylation, and activated AMP-activated protein kinase (AMPK). To sum up, this study demonstrated that VP exists hepatoprotective abilities on APAP-induced ALI, primarily by suppressing the phosphorylation of NF-κB/STAT3 cascade and ERK-JNK and inducing AMPK activation to alleviate oxidative stress and inflammation.

Prospective Application of Tannic Acid in Acetaminophen (APAP)-Induced Acute Liver Failure

This study investigated the effect of tannic acid (TA), a natural plant-derived polyphenol, on hepatocyte viability and function, focusing on both hepatoprotective and hepatocurative aspects within liver failure models. In an in vitro prevention model, the TA-containing group exhibited 1.5-fold and 59-fold higher relative cell viability and albumin synthesis, respectively, in injured mature hepatocytes (MHs) and 1.14-fold and 1.10-fold higher values in injured small hepatocytes (SHs), compared with the TA-free group. In the in vitro curative model, the TA-containing group exhibited 3.25-fold and 113-fold higher relative cell viability and albumin synthesis, respectively, in injured MHs and 0.36-fold and 3.55-fold higher values in injured SHs, compared with the TA-free group. In the in vivo disease model, the administration of 300 μL of 1 μg/mL TA significantly mitigated acute liver failure damage and post-APAP toxicity in mice. This was evident in serum analysis, where the levels of alanine transaminase, aspartate aminotransferase, and total bilirubin notably decreased, in agreement with histological observations. The study findings reveal that TA can enhance hepatic function at specific additive concentrations. Furthermore, even when injured by APAP, hepatocytes could revert to their preinjury state after additional TA supplementation. Additionally, pretreating hepatocytes with TA can alleviate subsequent damage. Thus, TA holds clinical potential in the treatment of APAP-induced liver failure.

The hepatotoxicity assessment of micro/nanoplastics: A preliminary study to apply the adverse outcome pathways

Plastic pollution has become a significant global problem over the years, leading to the continuous decomposition and accumulation of micro/nanoplastics (MNPLs) in the environment. As a result, human exposure to these MNPLs is inevitable. The liver, in particular, is highly susceptible to potential MNPL toxicity. In this study, we systematically reviewed the current literature on MNPLs-induced hepatotoxicity and collected data on toxic events occurring at different biological levels. Then, to better understand the cause-mechanism causality, we developed an Adverse Outcome Pathway (AOP) framework for MNPLs-induced hepatotoxicity. The AOP framework provided insights into the mechanism of MNPL-induced hepatotoxicity and highlighted potential health risks such as liver dysfunction and inflammation, metabolism disorders and liver fibrosis. Moreover, we discussed the potential application of emerging toxicological models in the hepatotoxicity study. Liver organoids and liver-on-chips, which can simulate the structure and function of the liver in vitro, offer a promising alternative platform for toxicity testing and risk assessment. We proposed combining the AOP framework with these emerging toxicological models to improve our understanding of the hepatotoxic effects of MNPLs. Overall, this study performed a preliminary exploration of novel toxicological methodologies to assess the hepatotoxicity of MNPLs, providing a deeper understanding of environmental toxicology.

Natural Products for Acetaminophen-Induced Acute Liver Injury: A Review

The liver plays a vital role in metabolism, synthesis, and detoxification, but it is susceptible to damage from various factors such as viral infections, drug reactions, excessive alcohol consumption, and autoimmune diseases. This susceptibility is particularly problematic for patients requiring medication, as drug-induced liver injury often leads to underestimation, misdiagnosis, and difficulties in treatment. Acetaminophen (APAP) is a widely used and safe drug in therapeutic doses but can cause liver toxicity when taken in excessive amounts. This study aimed to investigate the hepatotoxicity of APAP and explore potential treatment strategies using a mouse model of APAP-induced liver injury. The study involved the evaluation of various natural products for their therapeutic potential. The findings revealed that natural products demonstrated promising hepatoprotective effects, potentially alleviating liver damage and improving liver function through various mechanisms such as oxidative stress and inflammation, which cause changes in signaling pathways. These results underscore the importance of exploring novel treatment options for drug-induced liver injury, suggesting that further research in this area could lead to the development of effective preventive and therapeutic interventions, ultimately benefiting patients with liver injury caused by medicine.

Wolfberry, Yam, and Chrysanthemum polysaccharides increased intestinal Akkermansia muciniphila abundance and hepatic YAP1 expression to alleviate DILI

Drug-induced liver injury (DILI) is frequently induced by high dose of acetaminophen (APAP) and is concomitant with disturbances of gut flora. Akkermansia muciniphila is beneficial for the repair of liver injury. Lycium barbarum polysaccharide, yam polysaccharide, and chrysanthemum polysaccharide all have anti-inflammatory and antioxidation effects. The objective of this study is to investigate the potential of lycium barbarum polysaccharide, yam polysaccharide, and chrysanthemum polysaccharide (LYC) in improving DILI by increasing the abundance of A. muciniphila. Initially, screening for the optimal concentrations of wolfberry, yam, and chrysanthemum (WYC) or LYC to promote A. muciniphila proliferation in vitro and validated in antibiotic (ATB)-treated KM mice. Subsequently, APAP-induced DILI model in BALB/c mice were constructed to examine the treatment effects of LYC. Our findings indicate that the optimal concentration ratio of WYC was 2:3:2, and LYC was 1:1:1. WYC increased A. muciniphila proliferation in vitro and in ATB-treated mice under this ratio. Meanwhile, LYC increased A. muciniphila abundance in vitro and the combination LYC with A. muciniphila promoted the proliferation of A. muciniphila in ATB-treated mice. The overdose of APAP resulted in the impairment of the intestinal barrier function and subsequent leakage of lipopolysaccharide (LPS). Moreover, LYC increased A. muciniphila abundance, reduced intestinal inflammation and permeability, and upregulated the expression of the tight junction protein zonula occludens protein 1 (ZO-1) and occludin contents in the gut. Lastly, LYC inhibited LPS leakage and upregulated hepatic YAP1 expression, ultimately leading to the repair of DILI.

GeoDILI: A Robust and Interpretable Model for Drug-Induced Liver Injury Prediction Using Graph Neural Network-Based Molecular Geometric Representation

Drug-induced liver injury (DILI) is a significant cause of drug failure and withdrawal due to liver damage. Accurate prediction of hepatotoxic compounds is crucial for safe drug development. Several DILI prediction models have been published, but they are built on different data sets, making it difficult to compare model performance. Moreover, most existing models are based on molecular fingerprints or descriptors, neglecting molecular geometric properties and lacking interpretability. To address these limitations, we developed GeoDILI, an interpretable graph neural network that uses a molecular geometric representation. First, we utilized a geometry-based pretrained molecular representation and optimized it on the DILI data set to improve predictive performance. Second, we leveraged gradient information to obtain high-precision atomic-level weights and deduce the dominant substructure. We benchmarked GeoDILI against recently published DILI prediction models, as well as popular GNN models and fingerprint-based machine learning models using the same data set, showing superior predictive performance of our proposed model. We applied the interpretable method in the DILI data set and derived seven precise and mechanistically elucidated structural alerts. Overall, GeoDILI provides a promising approach for accurate and interpretable DILI prediction with potential applications in drug discovery and safety assessment. The data and source code are available at GitHub repository (https://github.com/CSU-QJY/GeoDILI).

Epidemiology and Management of Drug-induced Liver Injury: Importance of the Updated RUCAM

Drug-induced liver injury (DILI) is a major cause of acute liver injury, liver failure, and liver transplantation worldwide. In recent years, immune checkpoint inhibitors have become widely used. This has led to an increase in DILI, for which pathophysiology and management methods differ significantly from the past. As the number of cases of acute liver injury and liver transplantation due to DILI is expected to increase, information about a DILI is becoming more valuable. DILI is classified into two types according to its etiology: intrinsic DILI, in which the drug or its metabolites cause liver damage that is dose-dependent and predictable; and idiosyncratic DILI, in which liver damage is also dose-independent but unpredictable. In addition, depending on the course of the disease, chronic DILI or drug-induced autoimmune hepatitis may be present. The number of DILI cases caused by antimicrobial agents is decreasing, whereas that caused by drugs for malignant tumors and health foods is increasing. The Roussel Uclaf Causality Assessment Method is widely used to assess causality in DILI. Liver injury is a type of immune-related adverse event. The pattern of hepatic injury in immune-related adverse events is mostly hepatocellular, but mixed type and bile stasis have also been reported. Sclerosing cholangitis caused by immune checkpoint inhibitors has also been reported as a unique type of injury. Treatment mainly comprises withdrawal of immune checkpoint inhibitors and steroid administration; however, mycophenolate mofetil may be considered if the disease is refractory to steroids.

Revealing how phenytoin triggers liver damage and the potential protective effects of Balanites Aegyptiaca fruit extracts: Exploring Nrf2/MAPK/ Beclin-1 signaling pathways

Phenytoin-induced liver injury (PHT ILII) is a serious condition that may necessitate discontinuation of the drug. This study investigates the mechanisms of PHT ILII and evaluates the protective effects of Balanites Aegyptiaca (BA) fruit extracts on the liver. We focus on the Nrf2/MAPK/NF-κB/Beclin-1 signaling pathways involved in oxidative stress and inflammation from drug-induced liver injury. Phytochemical analyses of BA fruit extracts (Bu-F and EA-F) are conducted. Molecular docking techniques explore the interaction between phenytoin (PHT) and the Nrf2/MAPK/NF-κB/Beclin-1 pathways. Thirty-six male rats are divided into Control, Bu-F, EA-F, PHT, Bu-F/PHT, and EA-F/PHT groups, and they are observed for 45 days. EA-F extract is rich in phenolics/flavonoids, while Bu-F extract mainly contains saponins.PHT ILII causes histological damage in liver tissues and affects Nrf-2, MAPK, TNF-α, IL-1β, Mcp-1, Beclin-1, iNOS expression, and liver function markers (ALT, AST, ALP). However, EA-F/Bu-F extracts effectively improve the histological structure and significantly reduce biochemical/immunohistochemical parameters, restoring them to near-normal levels. EA-F extract is particularly effective.In conclusion, the Nrf2/MAPK /Beclin-1 pathways play a critical role in the development of PHT ILII. BA fruit extracts show promise as hepato-protective agents, with the EA-F extract demonstrating superior efficacy. These results lay the groundwork for new treatments for PHT ILII and drug-induced liver injuries.

Vine tea extract ameliorated acute liver injury by inhibiting hepatic autophagy and reversing abnormal bile acid metabolism

Gut microbiota disturbance, autophagy dysregulation, and accumulation of hepatic bile acids (BAs) are essential features of liver injury. Therefore, regulating autophagy and BA metabolism are potential strategies for treating liver diseases. Vine tea has been seen beyond a pleasant tea in food science. Our previous study found that vine tea extract (VTE) intervention alleviated acute liver injury (ALI) by restoring gut microbiota dysbiosis. In this study, we aim to investigate the effect of VTE on carbon tetrachloride (CCl4)-induced hepatic autophagy and BA metabolism disorder in mice. The results showed that VTE effectively suppressed CCl4-induced liver fibrosis and hepatic autophagy. LC-MS/MS assay suggested that VTE affected fecal BA production by reducing the fecal BA levels and improving cholestasis in ALI mice. Besides, VTE inhibited BA synthesis, promoted BA transport in the liver, and enhanced BA reabsorption in the ileum through the farnesoid X receptor (FXR)-related signaling pathway. The hepatic expressions of Fxr and Abca1 were elevated by VTE. Finally, the depletion of gut microbiota in ALI mice had a negative impact on abnormal autophagy and BA metabolism. It was also noted that the administration of VTE did not provide any additional improvement in this regard. Overall, VTE ameliorated ALI by reversing hepatic autophagy and abnormal BA metabolism, and the beneficial effects of VTE on liver injury depended on the existence of gut microbiota.

Reparative and Antioxidant Effects of New Analogues of Immunomodulator Thymogen in Experimental Model of Liver Damage

We studied the reparative and antioxidant effects of Thymogen and its new structural analogues obtained by binding amino acid D-Ala to the N- or C-end of the peptide molecule in acute toxic hepatopathy. Intragastric administration of carbon tetrachloride for 5 days caused the development of fat degeneration of hepatocytes, a decrease in catalase activity, and an increase in malondialdehyde concentration. Administration of peptides suppressed oxidative peroxidation and stimulated reparative regeneration of hepatocytes; Thymogen analogues produced more pronounced hepatotropic and antioxidant effects than Thymogen. Inclusion of D-Ala enhanced the effect of Thymogen on the processes of regeneration in hepatocytes and the antioxidant effect under conditions of acute carbon tetrachloride hepatopathy. The highest efficiency was achieved when the amino acid was added to the C-end of the molecule.

Chemistry-Based Modeling on Phenotype-Based Drug-Induced Liver Injury Annotation: From Public to Proprietary Data

Drug-induced liver injury (DILI) is an important safety concern and a major reason to remove a drug from the market. Advancements in recent machine learning methods have led to a wide range of in silico models for DILI predictive methods based on molecule chemical structures (fingerprints). Existing publicly available DILI data sets used for model building are based on the interpretation of drug labels or patient case reports, resulting in a typical binary clinical DILI annotation. We developed a novel phenotype-based annotation to process hepatotoxicity information extracted from repeated dose in vivo preclinical toxicology studies using INHAND annotation to provide a more informative and reliable data set for machine learning algorithms. This work resulted in a data set of 430 unique compounds covering diverse liver pathology findings which were utilized to develop multiple DILI prediction models trained on the publicly available data (TG-GATEs) using the compound's fingerprint. We demonstrate that the TG-GATEs compounds DILI labels can be predicted well and how the differences between TG-GATEs and the external test compounds (Johnson & Johnson) impact the model generalization performance.

4-hydroxylonchocarpin and corylifol A: The potential hepatotoxic components of Psoralea corylifolia L

Psoralea corylifolia L. (P. corylifolia) has attracted increasing attention because of its potential hepatotoxicity. In this study, we used network analysis (toxic component and hepatotoxic target prediction, proteinprotein interaction, GO enrichment analysis, KEGG pathway analysis, and molecular docking) to predict the components and mechanism of P. corylifolia-induced hepatotoxicity and then selected 4-hydroxylonchocarpin and corylifol A for experimental verification. HepG2 cells were treated with low, medium, and high concentrations of 4-hydroxylonchocarpin or corylifol A. The activities of ALT, AST, and LDH in cell culture media and the MDA level, SOD activity, and GSH level in cell extracts were measured. Moreover, apoptosis, ROS levels, and mitochondrial membrane potential were evaluated. The results showed that the activities of ALT, AST, and LDH in the culture medium increased, and hepatocyte apoptosis increased. The level of MDA increased, and the activity of SOD and level of GSH decreased, and the ROS level increased with 4-hydroxylonchocarpin and corylifol A intervention. Furthermore, the mitochondrial membrane potential decreased in the 4-hydroxylonchocarpin and corylifol A groups. This study suggests that 4-hydroxylonchocarpin and corylifol A cause hepatocyte injury and apoptosis by inducing oxidative stress and mitochondrial dysfunction, suggesting that these compounds may be the potential hepatotoxic components of P. corylifolia.

Revealing the role of nitroxyl during hepatic ischemia-reperfusion injury with a NIR-II luminescent nanoprobe

Hepatic ischemia-reperfusion injury (HIRI) can severely impair liver function and has a potential relationship with reactive nitrogen species. Nitroxyl (HNO) has been discovered to be involved in some biological functions and pharmacological activities. However, till now, there has been no knowledge of the role of HNO in the HIRI process, mainly because accurately tracking its fluctuation at the molecular level in vivo is extremely difficult. Herein, we developed a responsive ratiometric near-infrared-II (NIR-II) nanoprobe with rare earth ions-doped nanoparticles (RENPs) as the luminophore and a molecular trigger that can specifically react with HNO to regulate the NIR-II emission of RENPs. With this nanoprobe, we revealed the relationship between HNO and the HIRI process and demonstrated that HNO may be a product of stress reactions during HIRI. This work not only creates a useful tool for visually tracking HNO in vivo but also provides first-hand information about its role in HIRI.

Synergistic Effects of Vitis vinifera L. and Centella asiatica against CCl4-Induced Liver Injury in Mice

Liver injury can be acute or chronic, resulting from a variety of factors, including viral hepatitis, drug overdose, idiosyncratic drug reaction, or toxins, while the progression of pathogenesis in the liver rises due to the involvement of numerous cytokines and growth factor mediators. Thus, the identification of more effective biomarker-based active phytochemicals isolated from medicinal plants is a promising strategy to protect against CCl₄-induced liver injury. Vitis vinifera L. (VE) and Centella asiatica (CE) are well-known medicinal plants that possess anti-inflammatory and antioxidant properties. However, synergism between the two has not previously been studied. Here, we investigated the synergistic effects of a V. vinifera L. (VE) leaf, C. asiatica (CE) extract combination (VCEC) against CCl₄-induced liver injury. Acute liver injury was induced by a single intraperitoneal administration of CCl₄ (1 mL/kg). VCEC was administered orally for three consecutive days at various concentrations (100 and 200 mg/kg) prior to CCl₄ injection. The extent of liver injury and the protective effects of VCEC were evaluated by biochemical analysis and histopathological studies. Oxidative stress was evaluated by measuring malondialdehyde (MDA) and glutathione (GSH) levels and Western blotting. VCEC treatment significantly reduced serum transaminase levels (AST and ALT), tumor necrosis factor-α (TNF-α), and reactive oxygen species (ROS). CCl₄- induced apoptosis was inhibited by VCEC treatment by reducing cleaved caspase-3 and Bcl2-associated X protein (Bax). VCEC-treated mice significantly restored cytochrome P450 2E1, nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) expression in CCl4-treated mice. In addition, VCEC downregulated overexpression of proinflammatory cytokines and hepatic nuclear factor kappa B (NF-κB) and inhibited CCl4-mediated apoptosis. Collectively, VCEC exhibited synergistic protective effects against liver injury through its antioxidant, anti-inflammatory, and antiapoptotic ability against oxidative stress, inflammation, and apoptosis. Therefore, VCEC appears promising as a potential therapeutic agent for CCl₄-induced acute liver injury in mice.

System Biology Investigation Revealed Lipopolysaccharide and Alcohol-Induced Hepatocellular Carcinoma Resembled Hepatitis B Virus Immunobiology and Pathogenesis

Hepatitis B infection caused by the hepatitis B virus is a life-threatening cause of liver fibrosis, cirrhosis, and hepatocellular carcinoma. Researchers have produced multiple in vivo models for hepatitis B virus (HBV) and, currently, there are no specific laboratory animal models available to study HBV pathogenesis or immune response; nonetheless, their limitations prevent them from being used to study HBV pathogenesis, immune response, or therapeutic methods because HBV can only infect humans and chimpanzees. The current study is the first of its kind to identify a suitable chemically induced liver cirrhosis/HCC model that parallels HBV pathophysiology. Initially, data from the peer-reviewed literature and the GeneCards database were compiled to identify the genes that HBV and seven drugs (acetaminophen, isoniazid, alcohol, D-galactosamine, lipopolysaccharide, thioacetamide, and rifampicin) regulate. Functional enrichment analysis was performed in the STRING server. The network HBV/Chemical, genes, and pathways were constructed by Cytoscape 3.6.1. About 1546 genes were modulated by HBV, of which 25.2% and 17.6% of the genes were common for alcohol and lipopolysaccharide-induced hepatitis. In accordance with the enrichment analysis, HBV activates the signaling pathways for apoptosis, cell cycle, PI3K-Akt, TNF, JAK-STAT, MAPK, chemokines, NF-kappa B, and TGF-beta. In addition, alcohol and lipopolysaccharide significantly activated these pathways more than other chemicals, with higher gene counts and lower FDR scores. In conclusion, alcohol-induced hepatitis could be a suitable model to study chronic HBV infection and lipopolysaccharide-induced hepatitis for an acute inflammatory response to HBV.

Loss of microRNA-21 protects against acetaminophen-induced hepatotoxicity in mice

Acetaminophen (APAP)-induced Acute Liver Failure (ALF) is recognized as the most common cause of ALF in Western societies. APAP-induced ALF is characterized by coagulopathy, hepatic encephalopathy, multi-organ failure, and death. MicroRNAs are small, non-coding RNAs that regulate gene expression at the post-transcriptional level. MicroRNA-21 (miR-21) is dynamically expressed in the liver and is involved in the pathophysiology of both acute and chronic liver injury models. We hypothesize that miR-21genetic ablation attenuates hepatotoxicity following acetaminophen intoxication. Eight-week old miR-21knockout (miR21KO) or wild-type (WT) C57BL/6N male mice were injected with acetaminophen (APAP, 300 mg/kg BW) or saline. Mice were sacrificed 6 or 24 h post-injection. MiR21KO mice presented attenuation of liver enzymes ALT, AST, LDH compared with WT mice 24 h post-APAP treatment. Moreover, miR21KO mice had decreased hepatic DNA fragmentation and necrosis than WT mice after 24 h of APAP treatment. APAP-treated miR21KO mice showed increased levels of cell cycle regulators CYCLIN D1 and PCNA, increased autophagy markers expression (Map1LC3a, Sqstm1) and protein (LC3AB II/I, p62), and an attenuation of the APAP-induced hypofibrinolytic state via (PAI-1) compared with WT mice 24 post-APAP treatment. MiR-21 inhibition could be a novel therapeutic approach to mitigate APAP-induced hepatotoxicity and enhance survival during the regenerative phase, particularly to alter regeneration, autophagy, and fibrinolysis. Specifically, miR-21 inhibition could be particularly useful when APAP intoxication is detected at its late stages and the only available therapy is minimally effective.

Leonurine alleviates acetaminophen-induced acute liver injury by regulating the PI3K/AKT signaling pathway in mice

Leonurine (Leo) is a natural alkaloid isolated from the herb Leonurus japonicus Houtt. (Leonuri) that has been shown to inhibit oxidative stress and inflammation. However, the role and mechanism of Leo in acetaminophen (APAP)-induced acute liver injury (ALI) remain unknown. In this study, we investigated the protective effect of Leo against APAP-induced ALI and elucidated the molecular mechanism. Here, we showed that the damage to mouse primary hepatocytes (MPHs) induced by APAP was attenuated by treatment with Leo, which promoted proliferation and inhibited oxidative stress injury, and Leo significantly improved APAP-induced ALI in mice. Leo could protect against APAP-induced ALI by reducing serum aspartate aminotransferase (AST) and alanine transaminase (ALT) levels, hepatic histopathological damage, liver cell necrosis, inflammation, and oxidative stress-induced damage in vivo and in vitro. Moreover, the results indicated that Leo relieved APAP-induced liver cell necrosis by reducing the expression of Bax and cleaved caspase-3 and increasing Bcl-2 expression. Leo alleviated APAP-induced oxidative stress-induced damage by activating the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, which facilitated Nrf2 nuclear translocation and upregulated oxidative stress-related protein expression in liver tissues. Moreover, the results suggested that APAP-induced inflammation in the liver was suppressed by Leo by suppressing the Toll-like receptor 4 (TLR4) and NLR family pyrin domain containing 3 (NLRP3) pathways. In addition, Leo facilitated the activation of the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway in the liver tissue of ALI mice. Network pharmacology, molecular docking, and western blotting showed that PI3K was a potential target of Leo in the treatment of ALI. Molecular docking and cellular thermal shift assay (CETSA) indicated that Leo could stably bind to the PI3K protein. In conclusion, Leo attenuated ALI, and reversed liver cell necrosis, the inflammatory response and oxidative stress-induced damage by regulating the PI3K/AKT signaling pathway.

Microphysiological Models for Mechanistic-Based Prediction of Idiosyncratic DILI

Drug-induced liver injury (DILI) is a major contributor to high attrition rates among candidate and market drugs and a key regulatory, industry, and global health concern. While acute and dose-dependent DILI, namely, intrinsic DILI, is predictable and often reproducible in preclinical models, the nature of idiosyncratic DILI (iDILI) limits its mechanistic understanding due to the complex disease pathogenesis, and recapitulation using in vitro and in vivo models is extremely challenging. However, hepatic inflammation is a key feature of iDILI primarily orchestrated by the innate and adaptive immune system. This review summarizes the in vitro co-culture models that exploit the role of the immune system to investigate iDILI. Particularly, this review focuses on advancements in human-based 3D multicellular models attempting to supplement in vivo models that often lack predictability and display interspecies variations. Exploiting the immune-mediated mechanisms of iDILI, the inclusion of non-parenchymal cells in these hepatoxicity models, namely, Kupffer cells, stellate cells, dendritic cells, and liver sinusoidal endothelial cells, introduces heterotypic cell-cell interactions and mimics the hepatic microenvironment. Additionally, drugs recalled from the market in the US between 1996-2010 that were studies in these various models highlight the necessity for further harmonization and comparison of model characteristics. Challenges regarding disease-related endpoints, mimicking 3D architecture with different cell-cell contact, cell source, and the underlying multi-cellular and multi-stage mechanisms are described. It is our belief that progressing our understanding of the underlying pathogenesis of iDILI will provide mechanistic clues and a method for drug safety screening to better predict liver injury in clinical trials and post-marketing.

Bifidobacterium longum R0175 protects mice against APAP-induced liver injury by modulating the Nrf2 pathway

Acetaminophen (APAP) overdose is the most common driver of drug-induced liver injury (DILI) worldwide, and the gut microbiome plays a crucial role in this process. In this study, we estimated the effect of Bifidobacterium longum R0175 on APAP-induced liver injury in mice and discovered that B. longum R0175 alleviated liver injury by diminishing inflammation, reducing oxidative stress levels, inhibiting hepatocyte death and improving APAP-induced microbiome dysbiosis. Further studies revealed that the antioxidative effects of B. longum R0175 were primarily due to activation of the Nrf2 pathway, which was supported by the Nrf2 pathway inhibitor ML385 counteracting these ameliorative effects. B. longum R0175 modified intestinal metabolites, especially the key metabolite sedanolide, which could activate the Nrf2 pathway and contribute to the protective effects against APAP-induced liver injury. Moreover, we found that sedanolide exhibited close interrelationships with specific microbial taxa, indicating that this factor may be derived from gut microbes. In conclusion, our work demonstrated that B. longum R0175 could reduce oxidative damage, inflammation and hepatocyte death by activating the Nrf2 pathway. Importantly, we identified the microbiota-derived metabolite sedanolide, which was first discovered in the mouse intestine, as a key agonist of the Nrf2 pathway and primary effector of B. longum R0175 in APAP challenge. These findings provide new perspectives for APAP overdose therapy and demonstrate the enormous potential of B. longum R0175 in alleviating acute liver injury.

Xanthene-Based Nitric Oxide-Responsive Nanosensor for Photoacoustic Imaging in the SWIR Window

Shortwave infrared (SWIR) dyes are characterized by their ability to absorb light from 900 to 1400 nm, which is ideal for deep tissue imaging owing to minimized light scattering and interference from endogenous pigments. An approach to access such molecules is to tune the photophysical properties of known near-infrared dyes. Herein, we report the development of a series of easily accessible (three steps) SWIR xanthene dyes based on a dibenzazepine donor conjugated to thiophene (SCR-1), thienothiophene (SCR-2), or bithiophene (SCR-3). We leverage the fact that SCR-1 undergoes a bathochromic shift when aggregated for in vivo studies by developing a ratiometric nanoparticle for NO (rNP-NO), which we employed to successfully visualize pathological levels of nitric oxide in a drug-induced liver injury model via deep tissue SWIR photoacoustic (PA) imaging. Our work demonstrates how easily this dye series can be utilized as a component in nanosensor designs for imaging studies.

Dual-targetable fluorescent probe for mapping the fluctuation of peroxynitrite in drug-induced liver injury model

Drug-induced liver injury (DILI) is one of the most common and serious adverse drug reactions which can cause acute liver failure or even death in severe cases. With the incidence rate increasing over the years, DILI has became a frequent clinical liver disease and a global public health problem. As a biomarker of DILI, the detection of peroxynitrite (ONOO^-) has became a powerful tool for the early diagnosis of liver injury. Here, we synthesized five mitochondria-targetable probes, 1-5, for detecting endogenous ONOO^-. Through dye-screening, probe 5 was stood out by its excellent performance. In the presence of ONOO^-, the fluorescence signal of probe 5 reduced 40-fold in 19 s with a low detection limit (9.36 nM). At the same time, the transformation can be observed with the naked eye under sunlight or UV lamp without being affected by the other reactive species. Even better, with low toxicity and high biocompatibility, probe 5 could successfully detect endogenous ONOO^- in the mitochondrion of cells. Finally, probe 5 could specifically target the liver, and can be employed for monitoring the therapeutic effect of hepatoprotective medicine after drug-induced hepatotoxicity in vivo. In brief, probe 5 has the practical application capability for diagnosing the severity of the liver injury and researching the therapeutic effect of antidote in complex bio-systems.

The Role of the NLRP3 Inflammasome and Programmed Cell Death in Acute Liver Injury

Acute liver injury (ALI) is a globally important public health issue that, when severe, rapidly progresses to acute liver failure, seriously compromising the life safety of patients. The pathogenesis of ALI is defined by massive cell death in the liver, which triggers a cascade of immune responses. Studies have shown that the aberrant activation of the nod-like receptor protein 3 (NLRP3) inflammasome plays an important role in various types of ALI and that the activation of the NLRP3 inflammasome causes various types of programmed cell death (PCD), and these cell death effectors can in turn regulate NLRP3 inflammasome activation. This indicates that NLRP3 inflammasome activation is inextricably linked to PCD. In this review, we summarize the role of NLRP3 inflammasome activation and PCD in various types of ALI (APAP, liver ischemia reperfusion, CCl₄, alcohol, Con A, and LPS/D-GalN induced ALI) and analyze the underlying mechanisms to provide references for future relevant studies.

Hepatoprotective effects of norgalanthamine on carbon tetrachloride induced-hepatotoxicity in mice

Norgalanthamine is a major component of Crinum asiaticum var. japonicum that exhibits several biological activities. This study evaluated the anti-inflammatory and anti-oxidative properties of norgalanthamine in mice with carbon tetrachloride (CCl₄)-induced liver injury. Norgalanthamine (1 and 10 mg/kg) was orally administered to mice for 7 or 14 days, after which liver injury was induced by CCl₄ (1.5 ml/kg, i.p.). The vehicle and positive controls consisted of phosphate-buffered saline and silymarin (100 mg/kg), respectively. In CCl₄-injured mice, norgalanthamine pretreatment significantly reversed the increases in serum alanine aminotransferase, aspartate aminotransferase, and total bilirubin levels, and the decrease in the serum glucose level. In the liver, norgalanthamine restored the activities of the antioxidant enzymes superoxide dismutase and catalase, while reducing lipid accumulation and, concurrently, the expression of genes involved in lipid synthesis, including peroxisome proliferator-activated receptor γ and adipocyte protein-2. Norgalanthamine also ameliorated inflammation by down-regulating the expression of the pro-inflammatory mediators, TNF-α, IL-1β, and MCP-1, and up-regulating the Nrf2/HO-1 pathway. In addition, norgalanthamine decreased collagen deposition in liver tissue as shown on picrosirius red staining by down-regulating expression of the fibrosis-related genes αSMA and fibronectin. Collectively, these findings imply that norgalanthamine mitigates CCl₄-induced hepatic injury by increasing anti-oxidative activity, down-regulating pro-inflammatory mediators and fibrosis-related genes in the liver.HighlightsNorgalanthamine ameliorated the hepatotoxicity after CCl₄ injury.Norgalanthamine suppressed the activation of Kupffer cells and macrophages.Norgalanthamine down-regulated pro-inflammatory mediators.Norgalanthamine increased anti-oxidative activity via the Nrf2/HO-1 pathway.Norgalanthamine downregulated fibrosis-related genes in the liver.

An update on animal models of liver fibrosis

The development of liver fibrosis primarily determines quality of life as well as prognosis. Animal models are often used to model and understand the underlying mechanisms of human disease. Although organoids can be used to simulate organ development and disease, the technology still faces significant challenges. Therefore animal models are still irreplaceable at this stage. Currently, in vivo models of liver fibrosis can be classified into five categories based on etiology: chemical, dietary, surgical, transgenic, and immune. There is a wide variety of animal models of liver fibrosis with varying efficacy, which have different implications for proper understanding of the disease and effective screening of therapeutic agents. There is no high-quality literature recommending the most appropriate animal models. In this paper, we will describe the progress of commonly used animal models of liver fibrosis in terms of their development mechanisms, applications, advantages and disadvantages, and recommend appropriate animal models for different research purposes.

Wolfberry enhanced the abundance of Akkermansia muciniphila by YAP1 in mice with acetaminophen-induced liver injury

Drug-induced liver injury (DILI) by acetaminophen (APAP) was one of the most challenging liver diseases. Wolfberry (Lycium barbarum L.), a traditional Chinese medicinal material and food supplement, has a potential effect on increasing the abundance of Akkermansia muciniphila (A. muciniphila) in mice colons. However, the effect and mechanism of wolfberry remain unclear in APAP-induced DILI. In this study, wolfberry promoted the proliferation of activated-A. muciniphila in vitro and in vivo. For the first time, we detected that the activated-A. muciniphila but not the killed-A. muciniphila increased the expression level of Yes-associated protein 1 (YAP1) in the liver and alleviated liver injury in APAP-induced DILI mice. Mechanically, A. muciniphila improved the intestinal mucosal barrier and reduced lipopolysaccharide (LPS) content in the liver, leading to the increased expression level of YAP1. Furthermore, wolfberry increased the A. muciniphila abundance in the colon and YAP1 expression in the liver from APAP-induced DILI mice, which promoted the recovery of APAP-induced liver injury. Meanwhile, wolfberry combination with A. muciniphila synergistically increased AKK abundance and YAP1 expression in the liver. Our research provides an innovative strategy to improve DILI.

Extracellular vesicles as potential biomarkers and treatment options for liver failure: A systematic review up to March 2022

Introduction

Extracellular vesicles (EVs) carrying functional cargoes are emerging as biomarkers and treatment strategies in multiple liver diseases. Nevertheless, the potential of EVs in liver failure remains indistinct. In this systematic review, we comprehensively analyzed the potential of EVs as biomarkers of liver failure and the therapeutic effects and possible mechanisms of EVs for liver failure.

Methods

We conducted a systematic review by comprehensively searching the following electronic databases: PubMed, Web of Science, Embase and Cochrane Central Register of Controlled Trials from inception to March 2022. The used text words (synonyms and word variations) and database-specific subject headings included "Extracellular Vesicles", "Exosomes", "Liver Failure", "Liver Injury", etc.

Results

A total of 1479 studies were identified. After removing 680 duplicate studies and 742 irrelevant studies, 57 studies were finally retained and analyzed. Fourteen studies revealed EVs with functional cargoes could be used to make the diagnosis of liver failure and provide clues for early warning and prognostic assessment of patients with liver failure. Forty-three studies confirmed the administration of EVs from different sources alleviated hepatic damage and improved survival through inhibiting inflammatory response, oxidative stress as well as apoptosis or promoting hepatocyte regeneration and autophagy.

Conclusions

EVs and their cargoes can be used not only as superior biomarkers of early warning, early diagnosis and prognostic assessments for liver failure, but also as potentially effective treatment options for liver failure. In the future, large-scale studies are urgently needed to verify the diagnostic, predictive and therapeutic value of EVs for liver failure.

Transcriptional profiling of drug-induced liver injury biomarkers: association of hepatic Srebf1/Pparα signaling and crosstalk of thrombin, alcohol dehydrogenase, MDR and DNA damage regulators

Cell stress transcribing genes provide a diverse platform of molecular mediators that vary in response to toxicity. Common drug-induced liver injury (DILI) biomarkers are usually expressed in mild toxicity and limited to confirming it rather than categorizing its intensity. Thus, new parametric biomarkers are needed to be explored. Classifying the toxicological response based on the dose-level and severity of stimuli will aid in the evaluation and approach against drug exposure. The present research explored the involvement of gene expression of potential biomarkers as a severity-specific hallmark in different acetaminophen (APAP)-induced hepatotoxicity levels in C57BL/6 mice. The differentially expressed genes were annotated and analyzed using bioinformatics tools to predict canonical pathways altered by DILI. The results revealed alteration in genes encoding for antioxidant enhancement; Slc7a11, bile efflux; MDR4, fatty acid metabolism and transcriptional factors namely Srebf1 and Pparα. Potential APAP toxicity biomarkers included Adh1 and thrombin, and other DNA damage and stress chaperones which were changed at least fourfold between control and the three tested severity models. The current investigation demonstrates a dose-mediated association of several hallmark genes in APAP-induced liver damage and addressed the involvement of uncommonly studied molecular responses. Such biomarkers can be further developed into predictive models, translated for risk assessment against drug exposure and guide in building theragnostic targets.

Ameliorative Effects of Peptide Phe-Leu-Ala-Pro on Acute Liver and Kidney Injury Caused by CCl4 via Attenuation of Oxidative Stress and Inflammation

Acute liver injury (ALI) and acute kidney injury (AKI) are significantly affected by the antioxidant status. In the present study, the protective effect and mechanism of the collagen peptide Phe-Leu-Ala-Pro (FLAP) in mice with ALI and AKI induced by carbon tetrachloride (CCl₄) were examined. The results showed that FLAP effectively improved the liver mass index, the renal mass index, and the histopathological morphology. FLAP treatment significantly decreased the levels of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea nitrogen (BUN), and creatinine (CRE) but increased the activity of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px). The protein expression levels of nuclear factor E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), p-protein kinase B (p-AKT), and p-phosphatidylinositol-3-kinase (p-PI3K) in the liver and kidneys were significantly up-regulated after FLAP treatment. FLAP down-regulated the levels of interleukin-6 (IL-6), IL-1β, tumor necrosis factor-α (TNF-α), and nuclear factor-κ B (NF-κB) in liver and kidney tissues. Thus, FLAP may play a protective role in ALI and AKI by attenuating oxidative stress and inflammation mediated by the Nrf2/anti-response element (ARE) and PI3K/AKT/NF-κB pathways.

A Critical Appraisal of the Most Recent Investigations on the Hepatoprotective Action of Brazilian Plants

Conventional treatments for liver diseases are often burdened by side effects caused by chemicals. For minimizing this problem, the search for medicines based on natural products has increased. The objective of this review was to collect data on the potential hepatoprotective activity of plants of the Brazilian native flora. Special attention was given to the modes of extraction, activity indicators, and identification of the active compounds. The databases were Science direct, Pubmed, and Google Academic. Inclusion criteria were: (a) plants native to Brazil; (b) studies carried out during the last 15 years; (c) high-quality research. A fair number of communications met these criteria. Various parts of plants can be used, e.g., fruit peels, seeds, stem barks, and leaves. An outstanding characteristic of the active extracts is that they were mostly obtained from plant parts with low commercial potential, i.e., by-products or bio-residues. The hepatoprotective activities are exerted by constituents such as flavonoids, phenolic acids, vitamin C, phytosterols, and fructose poly- and oligosaccharides. Several Brazilian plants present excellent perspectives for the obtainment of hepatoprotective formulations. Very important is the economical perspective for the rural producers which may eventually increase their revenue by selling increasingly valued raw materials which otherwise would be wasted.

Kuhuang injection exerts a protective effect by activating PPAR-γ in an in vitro model of chlorpromazine-induced cholestatic liver injury constructed by tissue engineering

CONTEXT

Kuhuang (KH) injection is a widely used anticholestatic drug in the clinic and the mechanisms are still unclear.

OBJECTIVE

This study uses a new 3D tissue-engineered (TE) liver platform to study the ability of kuhuang to ameliorate liver injury induced by chlorpromazine (CPZ) and the possible mechanisms involved.

MATERIALS AND METHODS

The TE livers (n = 25) were divided into 5 groups (n = 5 livers/group) as 3D, 3D + CPZ, 3D + CPZ + KH, 3D + CPZ + GW9662 (a PPARγ inhibitor) and 3D + CPZ + KH + GW9662. The treatments with kuhuang (1 mg/mL) and GW9662 (10 μmol/L) were given to the desired groups on the 7th day of the experimental process. 20 μmol/L CPZ was added on the 8th day.

RESULTS

According to the 2D experimental results, the minimum effective concentration of kuhuang is 10 μg/mL and the optimal effective concentration is 1 mg/mL. Kuhuang ameliorated tissue damage in the TE livers both in terms of tissue structure and culture supernatant. Kuhuang significantly reduced TBA accumulation (38%) and downregulated CYP7A1 (38%) and CYP8B1 (79%). It reduced hepatic levels of ROS (14%), MDA (27%) but increased the levels of GSH (41%), SOD (12%), BSEP (4.4-fold), and MRP2 (74%). Moreover, kuhuang downregulated DR5 (99%) but increased the mRNA expression of PPARγ (4-fold). Molecular docking analyses determined the bioactivity of the active compounds of kuhuang through their specific bindings to PPARγ.

CONCLUSIONS

Kuhuang could alleviate CPZ-induced cholestatic liver injury by activating PPARγ to reduce oxidative stress. Applying kuhuang for the treatment of CPZ-induced liver injury could be suggested.

Targeting PARK7 Improves Acetaminophen-Induced Acute Liver Injury by Orchestrating Mitochondrial Quality Control and Metabolic Reprogramming

Mitochondrial dysfunction and oxidative stress are considered to be key events in acetaminophen (APAP)-induced acute liver injury. Mitochondrial quality control, including mitophagy and mitochondrial synthesis, can restore mitochondrial homeostasis and thus protect the liver. The role of PARK7, a mitochondrial stress protein, in regulating mitochondrial quality control in APAP-induced hepatotoxicity is unclear. In this study, L02 cells, AML12 cells and C57/BL6 mice were each used to establish models of APAP-induced acute liver injury. PARK7 was silenced in vitro by lentiviral transfection and knocked down in vivo by AAV adeno-associated virus. Changes in cell viability, apoptosis, reactive oxygen species (ROS) level, serum enzyme activity and pathological features were evaluated after APAP treatment. Western blotting, real-time PCR, immunofluorescence, electron microscopy and Seahorse assays were used to detect changes in key indicators of mitochondrial quality control. The results showed that APAP treatment decreased cell viability and increased the apoptosis rate, ROS levels, serum enzyme activity, pathological damage and PARK7 expression. PARK7 silencing or knockdown ameliorated APAP-induced damage to the cells and liver. Furthermore, PARK7 silencing enhanced mitophagy, increased mitochondrial synthesis, and led to a switch from oxidative phosphorylation to glycolysis. Taken together, these results suggest that PARK7 is involved in APAP-induced acute liver injury by regulating mitochondrial quality control and metabolic reprogramming. Therefore, PARK7 may be a promising therapeutic target for APAP-induced liver injury.

A non-human primate model of acute liver failure suitable for testing liver support systems

Acute hepatic failure is associated with high morbidity and mortality for which the only definitive therapy is liver transplantation. Some fraction of those who undergo emergency transplantation have been shown to recover native liver function when transplanted with an auxiliary hepatic graft that leaves part of the native liver intact. Thus, transplantation could have been averted with the development and use of some form of hepatic support. The costs of developing and testing liver support systems could be dramatically reduced by the availability of a reliable large animal model of hepatic failure with a large therapeutic window that allows the assessment of efficacy and timing of intervention. Non-lethal forms of hepatic injury were examined in combination with liver-directed radiation in non-human primates (NHPs) to develop a model of acute hepatic failure that mimics the human condition. Porcine hepatocyte transplantation was then tested as a potential therapy for acute hepatic failure. After liver-directed radiation therapy, delivery of a non-lethal hepatic ischemia-reperfusion injury reliably and rapidly generated liver failure providing conditions that can enable pre-clinical testing of liver support or replacement therapies. Unfortunately, in preliminary studies, low hepatocyte engraftment and over-immune suppression interfered with the ability to assess the efficacy of transplanted porcine hepatocytes in the model. A model of acute liver failure in NHPs was created that recapitulates the pathophysiology and pathology of the clinical condition, does so with reasonably predictable kinetics, and results in 100% mortality. The model allowed preliminary testing of xenogeneic hepatocyte transplantation as a potential therapy.

Hepatotoxicity due to herbal dietary supplements: Past, present and the future

Dietary supplements (DS) constitute a widely used group of products comprising vitamin, mineral, and botanical extract formulations. DS of botanical or herbal origins (HDS) comprise nearly 30% of all DS and are presented on the market either as single plant extracts or multi-extract-containing products. Despite generally safe toxicological profiles of most products currently present on the market, rising cases of liver injury caused by HDS - mostly by multi-ingredient and adulterated products - are of particular concern. Here we discuss the most prominent historical cases of HDS-induced hepatotoxicty - from Ephedra to Hydroxycut and OxyELITE Pro-NF, as well as products with suspected hepatotoxicity that are either currently on or are entering the market. We further provide discussion on overcoming the existing challenges with HDS-linked hepatotoxicity by introduction of advanced in silico, in vitro, in vivo, and microphysiological system approaches to address the matter of safety of those products before they reach the market.

Idiosyncratic liver injury induced by bolus combination treatment with emodin and 2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucopyranoside in rats

Polygoni Multiflori Radix (PMR) is a commonly used traditional Chinese medicine in clinical practice, while adverse effects of hepatotoxicity related to PMR have been frequently reported. The clinical case reports indicated that PMR hepatotoxicity could occur under both overdose medication/long-term exposure and low doses with short-duration (idiosyncratic) conditions. The combination treatment with emodin and 2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucopyranoside (TSG), two major PMR components, was reported to contribute to PMR hepatotoxicity after long-term treatment. However, the role of the combination treatment of these two components in PMR-induced idiosyncratic liver injury has not been clearly clarified. In this study, the LPS-mediated inflammatory stress model rats were adopted to explore the idiosyncratic liver injury induced by the bolus combination treatment with emodin and TSG. After a bolus oral administration with TSG (165 mg/kg), emodin (5 mg/kg) or their combination in both normal and LPS-mediated inflammatory stress model rats, the systemic/hepatic concentrations of emodin, emodin glucuronides and bile acids were determined; the hepatotoxicity assessments were conducted via monitoring histopathological changes and liver injury biomarkers (ALT and AST). Moreover, the protein expressions of bile acid homeostasis- and apoptosis-related proteins were examined. No liver damage was observed in the normal rats after a bolus dose with the individual or combination treatment, while the bolus combination treatment with emodin and TSG induced liver injury in the LPS-mediated inflammatory stress model rats, evidenced by the elevated plasma levels of alanine aminotransferase (∼66%) and aspartate aminotransferase (∼72%) accompanied by severe inflammatory cell infiltration and apoptotic hepatocytes in liver tissue. Moreover, such combination treatment at a bolus dose in the LPS-mediated inflammatory stress model rats could significantly elevate the hepatic TBA levels by about 45% via up-regulating the hepatic protein expression levels of bile acid synthesis enzymes and inhibiting that of bile acid efflux transporters and the expression levels of apoptosis-related proteins. Our study for the first time proved the major contribution of the combination treatment with emodin and TSG in PMR-induced idiosyncratic liver injury.