Treatment of Drug-Induced Liver Injury

Targeting chronic liver diseases: Molecular markers, drug delivery strategies and future perspectives

Chronic liver inflammation, a pervasive global health issue, results in millions of annual deaths due to its progression from fibrosis to the more severe forms of cirrhosis and hepatocellular carcinoma (HCC). This insidious condition stems from diverse factors such as obesity, genetic conditions, alcohol abuse, viral infections, autoimmune diseases, and toxic accumulation, manifesting as chronic liver diseases (CLDs) such as metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction-associated steatohepatitis (MASH), alcoholic liver disease (ALD), viral hepatitis, drug-induced liver injury, and autoimmune hepatitis. Late detection of CLDs necessitates effective treatments to inhibit and potentially reverse disease progression. However, current therapies exhibit limitations in consistency and safety. A potential breakthrough lies in nanoparticle-based drug delivery strategies, offering targeted delivery to specific liver cell types, such as hepatocytes, Kupffer cells, and hepatic stellate cells. This review explores molecular targets for CLD treatment, ongoing clinical trials, recent advances in nanoparticle-based drug delivery, and the future outlook of this research field. Early intervention is crucial for chronic liver disease. Having a comprehensive understanding of current treatments, molecular biomarkers and novel nanoparticle-based drug delivery strategies can have enormous impact in guiding future strategies for the prevention and treatment of CLDs.

The Mechanism of Catalpol to Improve Oxidative Damage of Dermal Fibroblasts Based on Nrf2/HO-1 Signaling Pathway

Objective

Catalpol, as a natural medicine small-molecule drug, has been proven to have anti-inflammatory and antioxidant pharmacological effects.

Methods

The effect of catalpol on oxidative damage of mouse epidermal fibroblast L929 model and its mechanism were investigated by using hydrogen peroxide model, CCK8 method, flow cytometry, and Western blot.

Results

The effect of catalpol on Nrf2/HO-1 signaling pathway was further studied to improve oxidative stress in cell models. The results showed that catalpol had no cytotoxicity to L929 cells, and inhibited the apoptosis of L929 cells after oxidative damage in a concentration-dependent manner, thus playing a role in cell protection. The oxidative damage of cells was inhibited by up-regulating the expression of the signature protein of Nrf2/HO-1 signaling pathway and inhibiting the interstitial formation of cells.

Conclusion

This study is a preliminary study on the protective function of catalpol against oxidation and apoptosis in dermal fibroblasts, which can provide a theoretical basis and drug guidance for promoting skin wound healing in the later stage.

CYP2E1 mediated advanced oxidation protein products exacerbate acetaminophen induced drug-derived liver injury in vitro and in vivo

Drug-induced liver injury (DILI) is prevalent in the treatment of chronic kidney disease (CKD). Advanced oxidation protein products (AOPPs) are markers of CKD progression and participate in the occurrence and development of liver diseases. However, the mechanisms underlying the regulation of DILI in CKD have not been established. Herein, we demonstrate the involvement of Cytochrome p450 2E1 (CYP2E1) in DILI induced by AOPPs is exacerbated by exposure to acetaminophen (APAP). We used a adenine-induced CKD model, a model of DILI induced by APAP, and the AOPPs model was generated by intraperitoneal injection. The decline in renal function was associated with a significantly increased concentration of Scr, BUN and AOPPs, and renal tissue fibrosis. The ALT, AST, and AOPPs levels and liver tissue necrosis increased significantly in CKD model group compared with the sodium carboxymethyl cellulose (CMCNa) group. In the AOPPs model, compared to the PBS controls, ALT, AST, and AOPP levels, and liver tissue necrosis increased significantly. In HepG2 or L0-2 cell lines, cell survival was significantly reduced in the AOPP + APAP treatment and CYP2E1 protein expression was increased. FPS-ZM1 or NAC attenuated the hepatocyte toxicity induced by AOPP + APAP and suppression of CYP2E1 expression. AOPPs exacerbated APAP-induced DILI through CYP2E1 signaling pathways. Protein uremic toxins, such as AOPPs, can modify drug toxicity in patients with CKD. This study provides new a rationale to reduce the generation of DILIs in clinical treatment in patients with CKD. AOPPs targeting may present a novel approach to reduce the occurrence of DILI.

Lycium barbarum L. Balanced intestinal flora with YAP1/FXR activation in drug-induced liver injury

Drug-induced liver injury (DILI) is a common and severe adverse drug reaction that can result in acute liver failure. Previously, we have shown that Lycium barbarum L. (wolfberry) ameliorated liver damage in acetaminophen (APAP)-induced DILI. Nevertheless, the mechanism needs further clarification. Herein, we utilized APAP-induced DILI mice to investigate how wolfberry impacts the gut-liver axis to mitigate liver damage. We showed that the abundance of Akkermansia muciniphila (A. muciniphila) was decreased, and intestinal microbiota was disrupted, while the expression levels of YAP1 and FXR-mediated CYP7A1 were reduced in the liver of DILI mice. Furthermore, wolfberry increased the abundance of A. muciniphila and the number of goblet cells in the intestines, while decreasing AST, ALT, and total bile acids (TBA) levels in the serum. Interestingly, A. muciniphila promoted YAP1 and FXR expression in hepatocytes, leading to the inhibition of CYP7A1 expression and a decrease in TBA content. Notably, wolfberry did not exert the beneficial effects mentioned above after the removal of intestinal bacteria by antibiotics (ATB)-containing water. Additionally, Yap1 knockout downregulated FXR expression and enhanced CYP7A1 expression in the liver of hepatocyte-specific Yap1 knockout mice. Therefore, wolfberry stimulated YAP1/FXR activation and reduced CYP7A1 expression by promoting the balance of intestinal microbiota, thereby suppressing the overproduction of bile acids.

Lansoprazole Ameliorates Isoniazid-Induced Liver Injury

Isoniazid is a first-line drug in antitubercular therapy. Isoniazid is one of the most commonly used drugs that can cause liver injury or acute liver failure, leading to death or emergency liver transplantation. Therapeutic approaches for the prevention of isoniazid-induced liver injury are yet to be established. In this study, we identified the gene expression signature for isoniazid-induced liver injury using a public transcriptome dataset, focusing on the differences in susceptibility to isoniazid in various mouse strains. We predicted that lansoprazole is a potentially protective drug against isoniazid-induced liver injury using connectivity mapping and an adverse event reporting system. We confirmed the protective effects of lansoprazole against isoniazid-induced liver injury using zebrafish and patients' electronic health records. These results suggest that lansoprazole can ameliorate isoniazid-induced liver injury. The integrative approach used in this study may be applied to identify novel functions of clinical drugs, leading to drug repositioning.

Therapeutic potential of stem cells in regeneration of liver in chronic liver diseases: Current perspectives and future challenges

The deposition of extracellular matrix and hyperplasia of connective tissue characterizes chronic liver disease called hepatic fibrosis. Progression of hepatic fibrosis may lead to hepatocellular carcinoma. At this stage, only liver transplantation is a viable option. However, the number of possible liver donors is less than the number of patients needing transplantation. Consequently, alternative cell therapies based on non-stem cells (e.g., fibroblasts, chondrocytes, keratinocytes, and hepatocytes) therapy may be able to postpone hepatic disease, but they are often ineffective. Thus, novel stem cell-based therapeutics might be potentially important cutting-edge approaches for treating liver diseases and reducing patient' suffering. Several signaling pathways provide targets for stem cell interventions. These include pathways such as TGF-β, STAT3/BCL-2, NADPH oxidase, Raf/MEK/ERK, Notch, and Wnt/β-catenin. Moreover, mesenchymal stem cells (MSCs) stimulate interleukin (IL)-10, which inhibits T-cells and converts M1 macrophages into M2 macrophages, producing an anti-inflammatory environment. Furthermore, it inhibits the action of CD4+ and CD8+ T cells and reduces the activity of TNF-α and interferon cytokines by enhancing IL-4 synthesis. Consequently, the immunomodulatory and anti-inflammatory capabilities of MSCs make them an attractive therapeutic approach. Importantly, MSCs can inhibit the activation of hepatic stellate cells, causing their apoptosis and subsequent promotion of hepatocyte proliferation, thereby replacing dead hepatocytes and reducing liver fibrosis. This review discusses the multidimensional therapeutic role of stem cells as cell-based therapeutics in liver fibrosis.

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.

Advances in Idiosyncratic Drug-Induced Liver Injury Issues: New Clinical and Mechanistic Analysis Due to Roussel Uclaf Causality Assessment Method Use

Clinical and mechanistic considerations in idiosyncratic drug-induced liver injury (iDILI) remain challenging topics when they are derived from mere case narratives or iDILI cases without valid diagnosis. To overcome these issues, attempts should be made on pathogenetic aspects based on published clinical iDILI cases firmly diagnosed by the original RUCAM (Roussel Uclaf Causality Assessment Method) or the RUCAM version updated in 2016. Analysis of RUCAM-based iDILI cases allowed for evaluating immune and genetic data obtained from the serum and the liver of affected patients. For instance, strong evidence for immune reactions in the liver of patients with RUCAM-based iDILI was provided by the detection of serum anti-CYP 2E1 due to drugs like volatile anesthetics sevoflurane and desflurane, partially associated with the formation of trifluoroacetyl (TFA) halide as toxic intermediates that form protein adducts and may generate reactive oxygen species (ROS). This is accompanied by production of anti-TFA antibodies detected in the serum of these patients. Other RUCAM-based studies on serum ANA (anti-nuclear antibodies) and SMA (anti-smooth muscle antibodies) associated with AIDILI (autoimmune DILI) syn DIAIH (drug-induced autoimmune hepatitis) provide additional evidence of immunological reactions with monocytes as one of several promoting immune cells. In addition, in the blood plasma of patients, mediators like the cytokines IL-22, IL-22 binding protein (IL-22BP), IL-6, IL-10, IL 12p70, IL-17A, IL-23, IP-10, or chemokines such as CD206 and sCD163 were found in DILI due to anti-tuberculosis drugs as ascertained by the prospective updated RUCAM, which scored a high causality. RUCAM-based analysis also provided compelling evidence of genetic factors such as HLA (human leucocyte antigen) alleles contributing to initiate iDILI by a few drugs. In conclusion, analysis of published RUCAM-based iDILI cases provided firm evidence of immune and genetic processes involved in iDILI caused by specific drugs.

Analysis of medical malpractice liability disputes related to novel antineoplastic drugs and research on risk prevention and control strategies

OBJECTIVE

To investigate the general characteristics of litigation cases of medical malpractice liability disputes (MMLDs) related to novel antineoplastic drugs (NADs), the drugs involved, as well as the common types of medical errors related to NADs and their damages in the process of diagnosis and treatment, with the aims of improving the level of rational medication use in the clinical application of NADs and actively prevent medical disputes.

METHODS

The China Judgments Online was searched for the cause of action using the key word "MMLDs" along with the name of 77 kinds of NADs. A total of 39 NAD litigation cases meeting the inclusion criteria from 1 January 2009 to 31 December 2021 were analyzed, and each potential adverse drug reaction (ADR) was reviewed to determine a causality assessment using the Naranjo algorithm for non-drug-induced liver injury (DILI) cases and the updated Roussel Uclaf Causality Assessment Method (RUCAM) for the DILI cases. Risk prevention and control strategies were recommended.

RESULTS

Cases that met the inclusion criteria increased substantially each year during the last six years, from three cases in 2009-2015 to 36 cases in 2016-2021. There were more cases in Eastern China than in other geographic regions. Most cases involved tertiary hospitals, patients between 25 and 60 years of age, and patients who were predominately male. There were 18 kinds of NADs involved in medical errors. The most common consequences of NADs were closely related to the death, disability, and increased treatment costs caused by ADRs, inadequate indications, delayed diagnosis and treatment, and misdiagnosis and mistreatment. The most frequent medical errors were medical technology errors, medical ethics errors and medical record writing/safekeeping errors. In two cases involving DILI, one case was unable to undergo further RUCAM scoring because the liver function indicators of the patient before and after treatment were not published.

CONCLUSION

The establishment of mechanisms to reduce the risks associated with the clinical application of NADs is warranted. Healthcare services must maintain strict adherence to the specific requirements of GPCANADs and drug instructions and strictly grasp the indications, contraindications, usage, and dosage of drugs, and strengthen the notification and management of off-label drug use. Monitoring patients for ADRs and preparing rescue and treatment measures for high-risk drugs may serve to reduce damages related to NADs. For DILI cases, medical and appraisal institutions should use RUCAM score to assess causal relationships.

Mitoquinone protects against acetaminophen-induced liver injury in an FSP1-dependent and GPX4-independent manner

Mitochondrial oxidative stress has been a crucial mediator in acetaminophen (APAP)-induced hepatotoxicity. MitoQ, an analog of coenzyme Q10, is targeted towards mitochondria and acts as a potent antioxidant. This study aimed to explore the effect of MitoQ on APAP-induced liver injury and its possible mechanisms. To investigate this, CD-1 mice and AML-12 cells were treated with APAP. Hepatic MDA and 4-HNE, two markers of lipid peroxidation (LPO), were elevated as early as 2 h after APAP. Oxidized lipids were rapidly upregulated in APAP-exposed AML-12 cells. Hepatocyte death and mitochondrial ultrastructure alterations were observed in APAP-induced acute liver injury. The in vitro experiments showed that mitochondrial membrane potentials and OXPHOS subunits were downregulated in APAP-exposed hepatocytes. MtROS and oxidized lipids were elevated in APAP-exposed hepatocytes. We discovered that APAP-induced hepatocyte death and liver injury were ameliorated by attenuation of protein nitration and LPO in MitoQ-pretreated mice. Mechanistically, knockdown of GPX4, a key enzyme for LPO defense systems, exacerbated APAP-induced oxidized lipids, but did not influence the protective effect of MitoQ on APAP-induced LPO and hepatocyte death. Whereas knockdown of FSP1, another key enzyme for LPO defense systems, had little effect on APAP-induced lipid oxidation but partially weakened the protection of MitoQ on APAP-induced LPO and hepatocyte death. These results suggest that MitoQ may alleviate APAP-evoked hepatotoxicity by eliminating protein nitration and suppressing hepatic LPO. MitoQ prevents APAP-induced liver injury partially dependent of FSP1 and independent of GPX4.

Molecular Idiosyncratic Toxicology of Drugs in the Human Liver Compared with Animals: Basic Considerations

Drug induced liver injury (DILI) occurs in patients exposed to drugs at recommended doses that leads to idiosyncratic DILI and provides an excellent human model with well described clinical features, liver injury pattern, and diagnostic criteria, based on patients assessed for causality using RUCAM (Roussel Uclaf Causality Assessment Method) as original method of 1993 or its update of 2016. Overall, 81,856 RUCAM based DILI cases have been published until mid of 2020, allowing now for an analysis of mechanistic issues of the disease. From selected DILI cases with verified diagnosis by using RUCAM, direct evidence was provided for the involvement of the innate and adapted immune system as well as genetic HLA (Human Leucocyte Antigen) genotypes. Direct evidence for a role of hepatic immune systems was substantiated by (1) the detection of anti-CYP (Cytochrome P450) isoforms in the plasma of affected patients, in line with the observation that 65% of the drugs most implicated in DILI are metabolized by a range of CYP isoforms, (2) the DIAIH (drug induced autoimmune hepatitis), a subgroup of idiosyncratic DILI, which is characterized by high RUCAM causality gradings and the detection of plasma antibodies such as positive serum anti-nuclear antibodies (ANA) and anti-smooth muscle antibodies (ASMA), rarely also anti-mitochondrial antibodies (AMA), (3) the effective treatment with glucocorticoids in part of an unselected RUCAM based DILI group, and (4) its rare association with the immune-triggered Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) caused by a small group of drugs. Direct evidence of a genetic basis of idiosyncratic DILI was shown by the association of several HLA genotypes for DILI caused by selected drugs. Finally, animal models of idiosyncratic DILI mimicking human immune and genetic features are not available and further search likely will be unsuccessful. In essence and based on cases of DILI with verified diagnosis using RUCAM for causality evaluation, there is now substantial direct evidence that immune mechanisms and genetics can account for idiosyncratic DILI by many but not all implicated drugs, which may help understand the mechanistic background of the disease and contribute to new approaches of therapy and prevention.

An Immunological Perspective on the Mechanism of Drug Induced Liver Injury: Focused on Drugs for Treatment of Hepatocellular Carcinoma and Liver Transplantation

The liver is frequently exposed to potentially toxic materials, and it is the primary site of clearance of foreign agents, along with many innate and adaptive immune cells. Subsequently, drug induced liver injury (DILI), which is caused by medications, herbs, and dietary supplements, often occurs and has become an important issue in liver diseases. Reactive metabolites or drug-protein complexes induce DILI via the activation of various innate and adaptive immune cells. There has been a revolutionary development of treatment drugs for hepatocellular carcinoma (HCC) and liver transplantation (LT), including immune checkpoint inhibitors (ICIs), that show high efficacy in patients with advanced HCC. Along with the high efficacy of novel drugs, DILI has become a pivotal issue in the use of new drugs, including ICIs. This review demonstrates the immunological mechanism of DILI, including the innate and adaptive immune systems. Moreover, it aims to provide drug treatment targets, describe the mechanisms of DILI, and detail the management of DILI caused by drugs for HCC and LT.