Can acetaminophen/dimethyl sulfoxide formulation prevent accidental and intentional acetaminophen hepatotoxicity?

Inhibitor of nuclear factor kappa B kinase subunit epsilon regulates murine acetaminophen toxicity via RIPK1/JNK

Drug-induced liver injury (DILI) still poses a major clinical challenge and is a leading cause of acute liver failure. Inhibitor of nuclear factor kappa B kinase subunit epsilon (IKBKE) is essential for inflammation and metabolic disorders. However, it is unclear how IKBKE regulates cellular damage in acetaminophen (APAP)-induced acute liver injury. Here, we found that the deficiency of IKBKE markedly aggravated APAP-induced acute liver injury by targeting RIPK1. We showed that APAP-treated IKBKE-deficient mice exhibited severer liver injury, worse mitochondrial integrity, and enhanced glutathione depletion than wild-type mice. IKBKE deficiency may directly upregulate the expression of total RIPK1 and the cleaved RIPK1, resulting in sustained JNK activation and increased translocation of RIPK1/JNK to mitochondria. Moreover, deficiency of IKBKE enhanced the expression of pro-inflammatory factors and inflammatory cell infiltration in the liver, especially neutrophils and monocytes. Inhibition of RIPK1 activity by necrostatin-1 significantly reduced APAP-induced liver damage. Thus, we have revealed a negative regulatory function of IKBKE, which acts as an RIPK1/JNK regulator to mediate APAP-induced hepatotoxicity. Targeting IKBKE/RIPK1 may serve as a potential therapeutic strategy for acute or chronic liver injury.

The Wnt/β-catenin signaling pathway plays a role in drug-induced liver injury by regulating cytochrome P450 2E1 expression

Drug-induced liver injury (DILI) is a major cause of acute liver failure and drug withdrawal. Cytochrome P450 (CYP) 2E1 is involved in the metabolism of several drugs, and can induce liver injury through the production of toxic metabolites and the generation of reactive oxygen species. This study aimed to elucidate the role of Wnt/β-catenin signaling in CYP2E1 regulation for drug-induced hepatotoxicity. To achieve this, mice were administered cisplatin or acetaminophen (APAP) 1 h after treatment with the CYP2E1 inhibitor dimethyl sulfoxide (DMSO), and histopathological and serum biochemical analyses were performed. APAP treatment induced hepatotoxicity, as evidenced by an increase in liver weight and serum ALT levels. Moreover, histological analysis indicated severe injury, including apoptosis, in the liver tissue of APAP-treated mice, which was confirmed by TUNEL assay. Additionally, APAP treatment suppressed the antioxidant capacity of the mice and increased the expression of the DNA damage markers γ-H2AX and p53. However, these effects of APAP on hepatotoxicity were significantly attenuated by DMSO treatment. Furthermore, the activation of Wnt/β-catenin signaling using the Wnt agonist CHIR99021 (CHIR) increased CYP2E1 expression in rat liver epithelial cells (WB-F344), whereas treatment with the Wnt/β-catenin antagonist IWP-2 inhibited nuclear β-catenin and CYP2E1 expression. Interestingly, APAP-induced cytotoxicity in WB-F344 cells was exacerbated by CHIR treatment and suppressed by IWP-2 treatment. Overall, these results showed that the Wnt/β-catenin signaling is involved in DILI through the upregulation of CYP2E1 expression by directly binding the transcription factor β-cat/TCF to the Cyp2e1 promoter, thus exacerbating DILI.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43188-023-00180-6.

Prenatal exposure to corn oil, CMC-Na or DMSO affects physical development and multi-organ functions in fetal mice

Corn oil, sodium carboxymethyl cellulose (CMC-Na), and dimethyl sulfoxide (DMSO) are widely used as solvents or suspensions in animal experiments, but the effects of prenatal exposure to them on fetal development have not been reported. In this study, Kunming mice were given a conventional dose of corn oil (9.2g/kg·d), CMC-Na (0.05g/kg·d) or DMSO (0.088g/kg·d) during gestation days 10-18, and the pregnancy outcome, fetal physical development, serum phenotype, and multi-organ function changes were observed. The results showed that corn oil decreased serum triglyceride level in males but increased their serum testosterone and CORT levels, and affected female placenta and female/male multi-organ functions (mainly bone, liver, kidney). CMC-Na increased female/male body lengths and tail lengths, decreased serum glucose and total cholesterol levels in males as well as increased their serum LDL-C/HDL-C ratio and testosterone level, decreased female serum bile acid level, and affected male/female placenta and multi-organ functions (mainly bone, liver, hippocampus). DMSO decreased male body weight and serum glucose level, decreased male/female serum bile acid levels, and affected male/female placenta and multi-organs functions (mainly bone, hippocampus, adrenal gland). In conclusion, prenatal exposure to a conventional dose of corn oil, CMC-Na or DMSO could affect fetal physical development and multi-organ functions, and has the characteristics of "multi-pathway, multi-organ and multi-target". This study provides the experimental basis for the rational selection of solvents or suspensions in pharmacology and toxicology studies. DATA AVAILABILITY: Data will be made available on request.

Mitochondrial dysfunction promotes the necroptosis of Purkinje cells in the cerebellum of acrylamide-exposed rats

Acrylamide (ACR) is a common neurotoxicant that can induce central-peripheral neuropathy in human beings. ACR from occupational setting and foods poses a potential threat to people's health. Purkinje cells are the only efferent source of cerebellum, and their output is responsible for coordinating motor activity. Recent studies have reported that Purkinje cell injury is one of the earliest neurotoxicity at any dose rate of ACR. However, the mechanism underlying ACR-mediated damage to Purkinje cells remains unclear. This research aimed to investigate whether necroptosis is involved in ACR-induced Purkinje cell death and its regulatory mechanism. In this study, rats were treated with ACR (40 mg/kg/every other day) for 6 weeks to establish an animal model of ACR neuropathy. Furthermore, an intervention experiment was achieved by rapamycin (RAPA), which is commonly used to activate mitophagy and maintain mitochondrial homeostasis. The results demonstrated ACR exposure caused necroptosis of Purkinje cells, mitochondrial dysfunction, and inflammatory response. By contrast, RAPA alleviated mitochondrial dysfunction and inhibited activation of necroptosis signaling pathway following ACR. In conclusion, our findings suggest that mitochondrial dysfunction and activation of necroptotic signaling are associated with the loss of Purkinje cells in ACR poisoning, which can be a potential therapeutic target for ACR neurotoxicity.

RIP1 kinase inactivation protects against acetaminophen-induced acute liver injury in mice

Many studies have investigated the role of receptor-interacting protein 1 (RIP1) kinase in acetaminophen (APAP) overdose-induced acute liver injury. However, the results were not consistent and there still remain controversies. Importantly, in these previous studies, the usage of DMSO to dissolve the RIP1 kinase inhibitor Nec-1, resulted in misleading conclusion. Our study aimed to determine the role of RIP1 kinase in APAP-induced liver injury, via genetically or pharmaceutically inhibition of RIP1 kinase activity. Our results indicated that APAP-induced liver injury was significantly attenuated in RIP1 kinase-dead (Rip1^K45A/K45A) mice compared to WT control. High dosage of APAP-induced mortality was also rescued by RIP1 kinase inactivation. In agreement, RIP1 kinase inhibitor, Nec-1 which was formulated with PEG400, could efficiently alleviate APAP-induced hepatotoxicity. For the underlying mechanism, our results suggested that RIP1 kinase inactivation did not influence the hepatic GSH depletion, but significantly reduced the hepatic cell death and inflammation induced by APAP treatment. Using bone marrow transplantation model, we also demonstrated that it was RIP1 kinase activity in tissue-resident hepatic cells other than hematopoietic-derived cells mainly responsible for APAP-induced liver injury. Our study confirmed the important role of RIP1 kinase activity in APAP-induced acute liver failure.

Hepatoprotective effect of forsythiaside a against acetaminophen-induced liver injury in zebrafish: Coupling network pharmacology with biochemical pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Forsythiae Fructus, the dried fruit of Forsythia suspensa (Thunb.) Vahl, is a commonly used traditional Chinese medicine and possesses various pharmacological activities, including anti-inflammation, anti-oxidant and liver protection.

AIM OF THE STUDY

Although acetaminophen (APAP) has been frequently used for its antipyretic and analgesic effects, it leads to liver injury at an overdose or long-term medication. Forsythiaside A (FA), the principal active component of Forsythiae Fructus, exerts prominent antioxidant, anti-inflammatory and hepatoprotective effects. However, the protective property and underlying mechanism of FA against APAP challenge have not yet been elucidated. Therefore, we aimed to explore the hepatoprotective effect and action mechanism of FA against APAP-induced liver injury in zebrafish.

MATERIALS AND METHODS

In this study, liver-specific transgenic zebrafish larvae (lfabp: EGFP) were used to investigate the protective effect of FA against overdose APAP exposure. The liver phenotype, morphological and biochemical assessments were carried out to evaluate the hepatoprotective effect of FA. Network pharmacology and molecular docking study were conducted to analyze the potential targets of FA in the treatment of APAP-induced liver injury. Finally, the mechanism of action was verified by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR).

RESULTS

The liver phenotype, morphological and biochemical assessments indicated that FA could mitigate APAP-triggered liver injury. Network pharmacology and molecular docking analysis indicated that the protective effect of FA might be related to the regulation of targets tumor necrosis factor (TNF), matrix metallopeptidase 9 (MMP9), matrix metallopeptidase 2 (MMP2), and phosphatidylinositol 3-kinase (PI3K). PCR results confirmed that FA could reverse the progressive alterations of genes involving in extracellular matrix remolding and PI3K/AKT-mediated apoptosis signaling pathway.

CONCLUSIONS

Our results indicated that FA could mitigate APAP-induced liver injury through modulating the remolding of extracellular matrix and PI3K/AKT-mediated apoptosis.

Photocatalytic and biodegradation treatments of paracetamol: investigation of the in vivo toxicity

Medicines and drugs consumption by all populations of the world can be expected to result in the contamination of the environment since 30-90% of residual drugs will be found into wastewaters. In this study, we investigate the degradation of acetaminophen, selected as a xenobiotic model molecule, via two separate procedures, the TiO₂ impregnated on cellulosic paper photocatalysis, and specific bacterial biodegradation process. Results showed that for initial drug content of 400 mg/L and after 5 hours of processing, around 85% of paracetamol was photocatalytically degraded. The use of Pseudomonas putida E1.21 isolate allowed an abatement of around 92% after 32 h of processing. The acetaminophen toxicity conducted in vivo on laboratory mice showed a net decrease of the creatinine release and enzymes activities like ALP, ALT, AST, and LDH decreased significantly (p < 0.05) when mice were treated distinctly by acetaminophen treated with UV/TiO₂ and the Pseudomonas putida E1.21 strain compared with the control experiments. CAT, MDA, and AchE serum level disruption measurement indicated a serious affection of the mice antioxidant system. These results were found to be in correlation with the ones of the histological analysis of the liver and kidney.