Drug-induced liver injury from antiepileptic drugs

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.

Black-Box Warnings of Antiseizure Medications: What is Inside the Box?

Antiseizure medications can cause serious adverse reactions and have deleterious drug interactions that often complicate the clinical management of patients. When the US Food and Drug Administration (FDA) wants to alert healthcare providers and patients about the risk of potentially serious or fatal drug reactions, the FDA requires the manufacturers of these medications to format these warnings within a "black-box" border, and prominently display this box on the first section of the package insert; such warnings are called "black-box warnings (BBWs)". The BBW is a way for the FDA to urge physicians to evaluate patients more rigorously and carefully weigh the risks and benefits, before prescribing medication that has the potential to cause serious adverse reactions, and to formulate a plan for close monitoring during therapy. The FDA BBW provides the extra layer of safety but many healthcare providers fail to comply with these warnings. Currently, there are 26 FDA-approved antiseizure medications in the US market, 38% of which have received BBWs, and most of the antiseizure medications with BBWs are older-generation drugs. Some antiseizure medications have multiple BBWs; for example, valproic acid has three BBWs including hepatotoxicity, fetal risk, and pancreatitis, carbamazepine has BBWs of serious skin and hematological reactions, and felbamate also has two BBWs including hepatic failure and aplastic anemia. The purpose of this review is to provide insight into each BBW received by antiseizure medications and discuss the FDA recommendations for evaluating the drug benefit/risk, and for monitoring parameters before the initiation of and during treatment.

Valproic acid induced liver injury: An insight into molecular toxicological mechanism

Valproic acid (VPA) is an anti-seizure drug that causes idiosyncratic liver injury. 2-propyl-4-pentenoic acid (Δ⁴VPA), a metabolite of VPA, has been implicated in VPA-induced hepatotoxicity. This review summarizes the pathogenesis involved in VPA-induced liver injury. The VPA induce liver injury mainly by i) liberation of Δ⁴VPA metabolites; ii) decrease in glutathione stores and antioxidants, resulting in oxidative stress; iii) inhibition of fatty acid β-oxidation, inducing mitochondrial DNA depletion and hypermethylation; a decrease in proton leak; oxidative phosphorylation impairment and ATP synthesis decrease; iv) induction of fatty liver via inhibition of carnitine palmitoyltransferase I, enhancing nuclear receptor peroxisome proliferator-activated receptor-gamma and acyl-CoA thioesterase 1, and inducing long-chain fatty acid uptake and triglyceride synthesis. VPA administration aggravates liver injury in individuals with metabolic syndromes. Therapeutic drug monitoring, routine serum levels of transaminases, ammonia, and lipid parameters during VPA therapy may thus be beneficial in improving the safety profile or preventing the progression of DILI.

Mechanism of drug-induced liver injury and hepatoprotective effects of natural drugs

Drug-induced liver injury (DILI) is a common adverse drug reaction (ADR) and a serious threat to health that affects disease treatments. At present, no targeted clinical drugs are available for DILI. Traditional natural medicines have been widely used as health products. Some natural medicines exert specific hepatoprotective effects, with few side effects and significant clinical efficacy. Thus, natural medicines may be a promising direction for DILI treatment. In this review, we summarize the current knowledge, common drugs and mechanisms of DILI, as well as the clinical trials of natural drugs and their bioactive components in anticipation of the future development of potential hepatoprotective drugs.

Drug-induced liver injury associated with antiseizure medications from the FDA Adverse Event Reporting System (FAERS)

PURPOSE

Treatment with antiseizure medications (ASMs) confers a risk of drug-induced liver injury (DILI), especially for older ASMs. We sought to quantify recent reports of DILI attributed to both older and newer generation ASMs and survey newly marketed ASMs for hepatotoxicity in a large post-marketing database.

METHODS

We queried over 2.6 million adverse event reports made to the FDA Adverse Event Reporting System (FAERS) database between July 1, 2018 and March 31, 2020 for DILI due to ASMs commonly used in clinical practice. Patient characteristics and outcomes were assessed. We calculated the reporting odds ratio (ROR) of DILI for each individual ASM versus all non-ASM reports.

RESULTS

A total of 2175 DILI cases were attributed to an ASM during the study period. 97.2% of these were designated as serious reactions, which include death, hospitalization, disability, and other life-threatening outcomes. A number of older and newer generation ASMs were associated with DILI, specifically: carbamazepine (ROR 2.92), phenobarbital (ROR 2.91), oxcarbazepine (ROR 2.58), phenytoin (ROR 2.40), valproate (ROR 2.22), lamotrigine (ROR 2.06), clobazam (ROR 1.67), levetiracetam (ROR 1.56), and diazepam (ROR 1.53). However, increased odds of DILI were not seen with zonisamide, perampanel, stiripentol, lacosamide, clonazepam, pregabalin, felbamate, eslicarbazepine, cannabidiol, topiramate, gabapentin, ethosuximide, brivaracetam, or primidone. Vigabatrin, tiagabine, and rufinamide all had zero reports of DILI.

CONCLUSIONS

The majority of newer generation ASMs were not significantly associated with DILI. Future studies utilizing FAERS in conjunction with other data sources will be critical for the ongoing surveillance of DILI, particularly as newly marketed ASMs continue to enter into widespread clinical use.

Anticonvulsant Effects of Dingxian Pill in Pentylenetetrazol-Kindled Rats

Dingxian pill has been used as an antiepilepsy agent in China from ancient to modern times, of which the concrete pharmacological characterization and the underlying molecular mechanism remain unclear. The present study was undertaken to investigate them by animal behavior, electroencephalogram (EEG), Morris water maze, immunohistochemistry, transcriptomics, and real-time PCR. In our results, the treatment of Dingxian pill dose-dependently inhibited PTZ-induced seizure-like behavior and reduced the seizure grades, LFP power spectral density, and brain wave of the epileptiform EEG component induced by PTZ. In Morris water maze tests, the learning and memory ability of kindled epileptic rats could be attenuated more efficiently by Dingxian pill. For the immediate early gene c-fos, the expression was reduced after Dingxian pill treatment, and the difference was significant between the treatment and the model group. Through the transcriptome analysis of the gene expression in hippocampus, Egr3, Nrg, Arc, and Ptgs2, closely related to epilepsy, had been proved to be downregulated by application of Dingxian pill. All of the results not only highlight the antiepileptic effects of Dingxian pill and its molecular mechanism, but also provide a modern validity theory for the clinical application of traditional Chinese medicine (TCM).

Effect of autophagy-associated proteins on the arecoline-induced liver injury in mice

Arecoline can be used to treat diseases including glaucoma and tapeworm infection, however, long-term administration can cause severe adverse effects, including oral submucosal fibrosis, oral cancer, hepatic injury and liver cancer. Autophagy serves a role in these injuries. The present study established a mouse model of arecoline-induced hepatic injury and investigated the role of autophagy-associated proteins in this injury. The results indicated that the expression levels of the autophagy marker protein microtubule associated protein 1 light chain 3 B (MAP1LC3B) and autophagy-promoting protein beclin 1 were elevated in the injured hepatic cells, while the expression levels of a well-known negative regulator of autophagy, mammalian target of rapamycin (mTOR), were reduced. Following treatment of the hepatic injury with glutathione, the liver function improved and liver damage was reduced effectively. Compared with the control group, the expression levels of both MAP1LC3B and beclin 1 were significantly upregulated in the glutathione-treated mice, but the expression of mTOR was significantly downregulated. It may be concluded that in the process of protecting against arecoline-induced hepatic injury, glutathione cooperates with mTOR and beclin 1 to accelerate autophagy, maintaining stable cell morphology and cellular functions.

Drug-Induced Liver Injury

Drug-induced liver injury (DILI) can result from both idiosyncratic and intrinsic mechanisms. This article discusses the clinical impact of DILI from a broad range of medications as well as herbal and dietary supplements. Risk factors for idiosyncratic DILI (IDILI) are the result of multiple host, environmental, and compound factors. Some triggers of IDILI often seen in critical care include antibiotics, antiepileptic medications, statins, novel anticoagulants, proton pump inhibitors, inhaled anesthetics, nonsteroidal anti-inflammatory agents, methotrexate, sulfasalazine, and azathioprine. The mechanism of IDILI due to these medications varies, and the resulting damage can be cholestatic, hepatocellular, or mixed. The primary treatment of IDILI is to discontinue the causative agent. DILI due to acetaminophen is intrinsic because the liver damage is predictably aligned with the dose ingested. Acute acetaminophen ingestion can be treated with activated charcoal or N-acetylcysteine. Future areas of research include identification of mitochondrial stress biomarkers and of the patients at highest risk for DILI.

Psychotropic drugs and liver disease: A critical review of pharmacokinetics and liver toxicity

The liver is the organ by which the majority of substances are metabolized, including psychotropic drugs. There are several pharmacokinetic changes in end-stage liver disease that can interfere with the metabolization of psychotropic drugs. This fact is particularly true in drugs with extensive first-pass metabolism, highly protein bound drugs and drugs depending on phase I hepatic metabolic reactions. Psychopharmacological agents are also associated with a risk of hepatotoxicity. The evidence is insufficient for definite conclusions regarding the prevalence and severity of psychiatric drug-induced liver injury. High-risk psychotropics are not advised when there is pre-existing liver disease, and after starting a psychotropic agent in a patient with hepatic impairment, frequent liver function/lesion monitoring is advised. The authors carefully review the pharmacokinetic disturbances induced by end-stage liver disease and the potential of psychopharmacological agents for liver toxicity.

Oxidative Stress and Inflammation in Hepatic Diseases: Therapeutic Possibilities of N-Acetylcysteine

Liver disease is highly prevalent in the world. Oxidative stress (OS) and inflammation are the most important pathogenetic events in liver diseases, regardless the different etiology and natural course. N-acetyl-l-cysteine (the active form) (NAC) is being studied in diseases characterized by increased OS or decreased glutathione (GSH) level. NAC acts mainly on the supply of cysteine for GSH synthesis. The objective of this review is to examine experimental and clinical studies that evaluate the antioxidant and anti-inflammatory roles of NAC in attenuating markers of inflammation and OS in hepatic damage. The results related to the supplementation of NAC in any form of administration and type of study are satisfactory in 85.5% (n = 59) of the cases evaluated (n = 69, 100%). Within this percentage, the dosage of NAC utilized in studies in vivo varied from 0.204 up to 2 g/kg/day. A standard experimental design of protection and treatment as well as the choice of the route of administration, with a broader evaluation of OS and inflammation markers in the serum or other biological matrixes, in animal models, are necessary. Clinical studies are urgently required, to have a clear view, so that, the professionals can be sure about the effectiveness and safety of NAC prescription.

Psychotropic medication use: what will it do to my liver?

Liver toxicity is the leading reason for withdrawal of marketed drugs and is a common reason for terminating the development of new drugs. Anticonvulsant, antidepressant, and antipsychotic drugs can be associated with significant liver injury or liver failure, but this is relatively rare compared to other non-psychotropic drug classes. More commonly, mild asymptomatic elevations in liver function tests are seen and these are not predictive of progression to more severe liver injury. Laboratory monitoring of liver function before and during treatment is recommended with the use of valproic acid and carbamazepine, but not for other psychotropic drugs, although regular laboratory testing is not a reliable method for detecting or preventing severe liver injury. Clinical monitoring for signs and symptoms suggesting hepatotoxicity or hypersensitivity reactions that affect the liver is more important.

Hyperammonemia enhances the function and expression of P-glycoprotein and Mrp2 at the blood-brain barrier through NF-κB

Ammonia is considered to be the main neurotoxin responsible for hepatic encephalopathy resulting from liver failure. Liver failure has been reported to alter expression and activity of P-glycoprotein (P-gp) and multidrug resistance-associated protein 2 (Mrp2) at the blood-brain barrier (BBB). The aim of this study was to investigate whether ammonia is involved in abnormalities of expression and activity of P-gp and Mrp2 at the BBB. Hyperammonemic rats were developed by an intraperitoneal injection of ammonium acetate (NH4 Ac, 4.5 mmol/kg). Results showed that Mrp2 function markedly increased in cortex and hippocampus of rats at 6 h following NH4 Ac administration. Significant increase in function of P-gp was observed in hippocampus of rats. Meanwhile, such alterations were in line with the increase in mRNA and protein levels of P-gp and Mrp2. Significant increase in levels of nuclear amount of nuclear factor-κB (NF-κB) p65 was also observed. Primarily cultured rat brain microvessel endothelial cells (rBMECs) were used for in vitro study. Data indicated that 24 h exposure to ammonia significantly increased function and expression of P-gp and Mrp2 in rBMECs, accompanied with activation of NF-κB. Furthermore, such alterations induced by ammonia were reversed by NF-κB inhibitor. In conclusion, this study demonstrates that hyperammonemia increases the function and expression of P-gp and Mrp2 at the BBB via activating NF-κB pathway. Hyperammonemia, a proverbial main factor responsible for neurocognitive disorder and blood-brain barrier (BBB) dysfunction resulting from liver failure, could increase the expression and activity of P-glycoprotein and multidrug resistance-associated protein 2 (Mrp2) at the BBB both in vivo and in vitro. Furthermore, the NF-κB activation stimulated by hyperammonemia may be the potential mechanism underlying such abnormalities induced by hyperammonemia.