A liver full of JNK: signaling in regulation of cell function and disease pathogenesis, and clinical approaches

Mefunidone ameliorates acute liver failure in mice by inhibiting MKK4-JNK pathway

Acute liver failure (ALF) is a critical condition that can lead to substantial liver dysfunction. It is characterized by complex clinical manifestations and rapid progression, presenting significant challenges in diagnosis and treatment. We investigated the protective effect of mefunidone (MFD), a novel antifibrosis pyridone agent, on ALF in mice, and explored its potential mechanism of action. MFD pretreatment can alleviate lipopolysaccharide (LPS) and d-galactosamine (D-GalN)-induced ALF, reduce hepatocyte apoptosis, and reduce inflammation and oxidative stress. Additionally, MFD alleviated LPS/D-GalN-stimulated reactive oxygen species (ROS) production and cell death in AML12 cells. RNA sequencing enrichment analysis showed that MFD significantly affected the Mitogen-Activated Protein Kinase (MAPK) pathway. In vivo and in vitro experiments showed that MFD inhibited MKK4 and JNK phosphorylation. JNK activation caused by MKK4 and JNK activators could eliminate the therapeutic effect of MFD on AML12. In addition, MFD pretreatment alleviated ConA-induced ALF, reduced inflammation and oxidative stress in mice, and reduced mouse mortality. These results suggest that MFD can potentially protect against ALF, partially by inhibiting the MKK4-JNK pathway, and is a promising new therapeutic drug for ALF.

Baicalin attenuates aflatoxin B1-induced hepatotoxicity via suppressing c-Jun-N-terminal kinase-mediated cell apoptosis

Aflatoxin B1 (AFB1) is classified as a Class I carcinogen and common pollutant in human and animal food products. Prolonged exposure to AFB1 can induce hepatocyte apoptosis and lead to hepatotoxicity. Therefore, preventing AFB1-induced hepatotoxicity remains a critical issue and is of great significance. Baicalin, a polyphenolic compound derived from Scutellaria baicalensis Georgi, has a variety of pharmacodynamic activities, such as antiapoptotic and anticancer activities. This study systematically investigated the alleviating effect of baicalin on AFB1-induced hepatotoxicity from the perspective of apoptosis and explored the possible molecular mechanism. In the normal human liver cell line L02, baicalin treatment significantly inhibited AFB1-induced c-Jun-N-terminal Kinase (JNK) activation and cell apoptosis. In addition, the in vitro mechanism study demonstrated that baicalin alleviates AFB1-induced hepatocyte apoptosis through suppressing the translocation of phosphorylated JNK to the nucleus and decreasing the phosphorylated c-Jun/c-Jun ratio and the Bax/Bcl2 ratio. Molecular docking and drug affinity responsive target stability assays demonstrated that baicalin has the potential to target JNK. This study provides a basis for the therapeutic effect of baicalin on hepatocyte apoptosis caused by AFB1, indicating that the development of baicalin and JNK pathway inhibitors has broad application prospects in the prevention of hepatotoxicity, especially hepatocyte apoptosis.

Kaempferol sophoroside glucoside mitigates acetaminophen-induced hepatotoxicity: Role of Nrf2/NF-κB and JNK/ASK-1 signaling pathways

APAP (Acetaminophen)-induced hepatic injury is a major public health threat that requires continuous searching for new effective therapeutics. KSG (Kaempferol-3-sophoroside-7-glucoside) is a kaempferol derivative that was separated from plant species belonging to different genera. This study explored the protective effects of KSG on ALI (acute liver injury) caused by APAP overdose in mice and elucidated its possible mechanisms. The results showed that KSG pretreatment alleviated APAP-induced hepatic damage as it reduced hepatic pathological lesions as well as the serum parameters of liver injury. Moreover, KSG opposed APAP-associated oxidative stress and augmented hepatic antioxidants. KSG suppressed the inflammatory response as it decreased the genetic and protein expression as well as the levels of inflammatory cytokines. Meanwhile, KSG enhanced the mRNA expression and level of anti-inflammatory cytokine, IL-10 (interleukin-10). KSG repressed the activation of NF-κB (nuclear-factor kappa-B), besides it promoted the activation of Nrf2 signaling. Additionally, KSG markedly hindered the elevation of ASK-1 (apoptosis-signal regulating-kinase-1) and JNK (c-Jun-N-terminal kinase). Furthermore, KSG suppressed APAP-induced apoptosis as it decreased the level and expression of Bax (BCL2-associated X-protein), and caspase-3 concurrent with an enhancement of anti-apoptotic protein, Bcl2 in the liver. More thoroughly, Computational studies reveal indispensable binding affinities between KSG and Keap1 (Kelch-like ECH-associated protein-1), ASK1 (apoptosis signal-regulating kinase-1), and JNK1 (c-Jun N-terminal protein kinase-1) with distinctive tendencies for selective inhibition. Taken together, our data showed the hepatoprotective capacity of KSG against APAP-produced ALI via modulation of Nrf2/NF-κB and JNK/ASK-1/caspase-3 signaling. Henceforth, KSG could be a promising hepatoprotective candidate for ALI.

Cldn4 overexpression promotes penile cavernous smooth muscle cell fibrotic response via the JNK signaling pathway

BACKGROUND

Erectile dysfunction (ED), defined as the inability to achieve or maintain a penile erection sufficient to satisfy sexual behavior, is prevalent worldwide.

AIM

Using previous research, bioinformatics, and experimental confirmation, we aimed to discover genes that contribute to ED through regulating hypoxia in corpus cavernosum smooth muscle cells (CCSMCs).

METHODS

We used the Gene Expression Omnibus to acquire the sequencing data of the corpus cavernosum transcriptome for diabetic ED and nerve injury type ED rats. We intersected the common differentially expressed genes. Further verification was performed using single cell sequencing. Real-time quantitative polymerase chain reaction and immunofluorescence were used to investigate whether the differentially expressed genes are found in the corpus cavernosum. We used induced hypoxia to assess cell viability changes, and we developed a lentivirus overexpressing Cldn4 for in vitro and in vivo experiments to measure changes in JNK signaling, fibrosis, hypoxia, and erectile function.

OUTCOMES

Our results indicate that targeting the JNK pathway and decreasing local hypoxia may be better options for therapeutic intervention to improve erectile function.

RESULTS

We identified Cldn4 and found its expression increased in the corpora cavernosa of the 2 datasets. In addition, we found that hypoxia can increase the expression of Cldn4, activate the JNK signaling pathway, and exacerbate fibrosis in CCSMCs. Cldn4 overexpression in CCSMCs activated the JNK signaling pathway and increased fibrotic protein expression. Last, rat corpus cavernosum overexpressing Cldn4 activated the JNK signaling pathway, increased local fibrosis, and impaired erectile function.

CLINICAL IMPLICATIONS

Through bioinformatics and in vitro and in vivo experiments, we found that Cldn4 has a negative effect on ED, and targeting Cldn4 may provide new ideas for ED treatment.

STRENGTHS AND LIMITATIONS

Although we have identified Cldn4 as a potential target for ED treatment, we have only conducted preliminary validation on CCMSCs, and we still need to further validate in other cell lines.

CONCLUSION

CCSMC hypoxia leads to increased Cldn4, in both nerve injury and diabetic ED rat models, and promotes fibrosis by activating the JNK signaling pathway.

ZBP1-mediated apoptosis and inflammation exacerbate steatotic liver ischemia/reperfusion injury

Steatotic donor livers are becoming more and more common in liver transplantation. However, the current use of steatotic grafts is less acceptable than normal grafts due to their higher susceptibility to ischemia/reperfusion (I/R) injury. To investigate the mechanism underlying the susceptibility of steatotic liver to I/R injury, we detected cell death markers and inflammation in clinical donor livers and animal models. We found that caspase-8-mediated hepatic apoptosis is activated in steatotic liver I/R injury. However, ablation of caspase-8 only slightly mitigated steatotic liver I/R injury without affecting inflammation. We further demonstrated that RIPK1 kinase induces both caspase-8-mediated apoptosis and cell death-independent inflammation. Inhibition of RIPK1 kinase significantly protects against steatotic liver I/R injury by alleviating both hepatic apoptosis and inflammation. Additionally, we found that RIPK1 activation is induced by Z-DNA binding protein 1 (ZBP1) but not the canonical TNF-α pathway during steatotic liver I/R injury. Deletion of ZBP1 substantially decreases the steatotic liver I/R injury. Mechanistically, ZBP1 is amplified by palmitic acid-activated JNK pathway in steatotic livers. Upon I/R injury, excessive reactive oxygen species trigger ZBP1 activation by inducing its aggregation independent of the Z-nucleic acids sensing action in steatotic livers, leading to the kinase activation of RIPK1 and the subsequent aggravation of liver injury. Thus, ZBP1-mediated RIPK1-driven apoptosis and inflammation exacerbate steatotic liver I/R injury, which could be targeted to protect steatotic donor livers during transplantation.

Inositol-requiring enzyme 1α and c-Jun N-terminal kinase axis activation contributes to intracellular lipid accumulation in calf hepatocytes

During the perinatal period, dairy cows undergo negative energy balance, resulting in elevated circulating levels of nonesterified fatty acids (NEFA). Although increased blood NEFA concentrations are a physiological adaptation of early lactation, excessive NEFA in dairy cows is a major cause of fatty liver. Aberrant lipid metabolism leads to hepatic lipid accumulation and subsequently the development of fatty liver. Both inositol-requiring enzyme 1α (IRE1α) and c-Jun N-terminal kinase (JNK) have been validated for their association with hepatic lipid accumulation, including their regulatory functions in calf hepatocyte insulin resistance, oxidative stress, and apoptosis. Meanwhile, both IRE1α and JNK are involved in lipid metabolism in nonruminants. Therefore, the aim of this study was to investigate how IRE1α and JNK regulate lipid metabolism in bovine hepatocytes. An experiment was conducted on randomly selected 10 healthy cows (hepatic triglyceride [TG] content <1%) and 10 cows with fatty liver (hepatic TG content >5%). Liver tissue and blood samples were collected from experimental cows. Serum concentrations of NEFA and β-hydroxybutyrate (BHB) were greater, whereas serum concentrations of glucose and milk production were lower in cows with fatty liver. The western blot results revealed that dairy cows with fatty liver had higher phosphorylation levels of JNK, c-Jun, and IRE1α in the liver tissue. Three in vitro experiments were conducted using primary calf hepatocytes isolated from 5 healthy calves (body weight: 30-40 kg; 1 d old). First, hepatocytes were treated with NEFA (1.2 mM) for 0.5, 1, 2, 3, 5, 7, 9, or 12 h, which showed that the phosphorylated levels of JNK, c-Jun, and IRE1α increased in both linear and quadratic effects. In the second experiment, hepatocytes were treated with high concentrations of NEFA (1.2 mM) for 12 h with or without SP600125, a canonical inhibitor of JNK. Western blot results showed that SP600125 treatment could decrease the expression of lipogenesis-associated proteins (PPARγ and SREBP-1c) and increase the expression of fatty acid oxidation (FAO)-associated proteins (CPT1A and PPARα) in NEFA-treated hepatocytes. The perturbed expression of lipogenesis-associated genes (FASN, ACACA, and CD36) and FAO-associated gene ACOX1 were also recovered by JNK inhibition, indicating that JNK reduced excessive NEFA-induced lipogenesis and FAO dysregulation in calf hepatocytes. Third, short hairpin RNA targeting IRE1α (sh-IRE1α) was transfected into calf hepatocytes to silence IRE1α, and KIRA6 was used to inhibit the kinase activity of IRE1α. The blockage of IRE1α could at least partially suppressed NEFA-induced JNK activation. Moreover, the blockage of IRE1α downregulated the expression of lipogenesis genes and upregulated the expression of FAO genes in NEFA-treated hepatocytes. In conclusion, these findings indicate that targeting the IRE1α-JNK axis can reduce NEFA-induced lipid accumulation in bovine hepatocytes by modulating lipogenesis and FAO. This may offer a prospective therapeutic target for fatty liver in dairy cows.

Alcohol-Associated Liver Disease Outcomes: Critical Mechanisms of Liver Injury Progression

Alcohol-associated liver disease (ALD) is a substantial cause of morbidity and mortality worldwide and represents a spectrum of liver injury beginning with hepatic steatosis (fatty liver) progressing to inflammation and culminating in cirrhosis. Multiple factors contribute to ALD progression and disease severity. Here, we overview several crucial mechanisms related to ALD end-stage outcome development, such as epigenetic changes, cell death, hemolysis, hepatic stellate cells activation, and hepatic fatty acid binding protein 4. Additionally, in this review, we also present two clinically relevant models using human precision-cut liver slices and hepatic organoids to examine ALD pathogenesis and progression.

Metformin and the Liver: Unlocking the Full Therapeutic Potential

Metformin is a highly effective medication for managing type 2 diabetes mellitus. Recent studies have shown that it has significant therapeutic benefits in various organ systems, particularly the liver. Although the effects of metformin on metabolic dysfunction-associated steatotic liver disease and metabolic dysfunction-associated steatohepatitis are still being debated, it has positive effects on cirrhosis and anti-tumoral properties, which can help prevent the development of hepatocellular carcinoma. Furthermore, it has been proven to improve insulin resistance and dyslipidaemia, commonly associated with liver diseases. While more studies are needed to fully determine the safety and effectiveness of metformin use in liver diseases, the results are highly promising. Indeed, metformin has a terrific potential for extending its full therapeutic properties beyond its traditional use in managing diabetes.

The Role of the Dysregulated JNK Signaling Pathway in the Pathogenesis of Human Diseases and Its Potential Therapeutic Strategies: A Comprehensive Review

JNK is named after c-Jun N-terminal kinase, as it is responsible for phosphorylating c-Jun. As a member of the mitogen-activated protein kinase (MAPK) family, JNK is also known as stress-activated kinase (SAPK) because it can be activated by extracellular stresses including growth factor, UV irradiation, and virus infection. Functionally, JNK regulates various cell behaviors such as cell differentiation, proliferation, survival, and metabolic reprogramming. Dysregulated JNK signaling contributes to several types of human diseases. Although the role of the JNK pathway in a single disease has been summarized in several previous publications, a comprehensive review of its role in multiple kinds of human diseases is missing. In this review, we begin by introducing the landmark discoveries, structures, tissue expression, and activation mechanisms of the JNK pathway. Next, we come to the focus of this work: a comprehensive summary of the role of the deregulated JNK pathway in multiple kinds of diseases. Beyond that, we also discuss the current strategies for targeting the JNK pathway for therapeutic intervention and summarize the application of JNK inhibitors as well as several challenges now faced. We expect that this review can provide a more comprehensive insight into the critical role of the JNK pathway in the pathogenesis of human diseases and hope that it also provides important clues for ameliorating disease conditions.

Pharmacological properties of Ensete glaucum seed extract: Novel insights for antidiabetic effects via modulation of oxidative stress, inflammation, apoptosis and MAPK signaling pathways

ETHNOPHAMACOLOGICAL RELEVANCE

Medicinal plants are increasingly making important contributions to diabetic treatment. Ensete glaucum seeds have been widely used in folk medicine to treat diabetes.

AIM OF THE STUDY

The study was aimed to investigate the protective effect and active mechanisms of E. glaucum seed extract (EGSE) against streptozotocin (STZ)-induced hyperglycemia.

MATERIALS AND METHODS

Hyperglycemic mice were treated with EGSE (25 and 50 mg/kg) or glibenclamide (5 mg/kg) once daily for 7 d. The effects of these treatments on changes in blood biochemical parameters, pancreatic, liver, and kidney histopathology, oxidative stress and inflammatory marker levels in pancreatic, hepatic, and renal tissues were assessed. Expression of several proteins in MAPK signaling pathway related to apoptosis in pancreatic tissue were investigated. Furthermore, ex vivo, in vitro, and in silico biological activities of EGSE and its compounds were also examined.

RESULTS

EGSE and glibenclamide increased notably insulin, reduced significantly glucose, AST, ALT, BUN and creatinine levels in blood. Pancreatic islets, hepatic and renal tissue structure were restored by EGSE or glibenclamide. EGSE showed significant anti-oxidative stress and anti-inflammatory effects by enhancing GSH level and dropping MDA, NF-κB, TNF-α and IL-6 levels in these tissues. Particularly, EGSE exhibited pancreatic protective effect against STZ-induced apoptosis through the MAPK signaling pathway by down-regulation of p-p38 MAPK, ERK1/2, JNK1, p-AMPK, Bax, Bax/Bcl-2, cytochrome c, cleaved-caspase 3 and PARP expression, and slight up-regulation of Bcl-2 expression. Moreover, EGSE inhibited intestinal glucose absorption, PTP1B, α-amylase, and α-glucosidase activities. Its isolated compounds (Afzelechin and coniferaldehyde) showed PTP1B and α-glucosidase inhibitory activities, and potent structure-activity relationships.

CONCLUSION

These findings indicated the hypoglycemic and protective effects of E. glaucum seed extract against the STZ diabetogenic action. E. glaucum seed is a potential candidate for further studies to confirm its activities as a therapeutic agent for diabetic patients.

Hepatocyte-specific mitogen-activated protein kinase phosphatase 1 in sexual dimorphism and susceptibility to alcohol induced liver injury

Background

It is well established that females are more susceptible to the toxic effects of alcohol, although the exact mechanisms are still poorly understood. Previous studies noted that alcohol reduces the expression of mitogen-activated protein kinase phosphatase 1 (MKP1), a negative regulator of mitogen-activated protein kinases (MAPK) in the liver. However, the role of hepatocyte- specific MKP1 in the pathogenesis of alcohol-associated liver disease (ALD) remains uncharacterized. This study aimed to evaluate the role of hepatocyte-specific MKP1 in the susceptibility and sexual dimorphism in alcohol-induced liver injury.

Methods

C57Bl/6 mice were used in an intragastric ethanol feeding model of alcohol-associated steatohepatitis (ASH). Hepatocyte-specific Mkp1-/- knockout and (Mkp1+/+ "f/f" male and female mice were subjected to the NIAAA chronic plus binge model. Primary mouse hepatocytes were used for in vitro studies. Liver RNA sequencing was performed on an Illumina NextSeq 500. Liver injury was evaluated by plasma alanine transaminase (ALT), hepatic ER stress and inflammation markers. Statistical analysis was carried out using ANOVA and the unpaired Student's t-test.

Results

ASH was associated with the severe injury accompanied by increased endoplasmic reticulum (ER) stress and significant downregulation of Dusp1 mRNA expression. In vitro, ethanol treatment resulted in a time-dependent decrease in Dusp1 mRNA and protein expression in primary hepatocytes in both males and females; however, this effect was significantly more pronounced in hepatocytes from females. In vivo, female mice developed more liver injury in a chronic plus binge model which was accompanied by a significant decrease in liver Dusp1 mRNA expression. In comparison, liver Dusp1 was not changed in male mice, while they developed milder injury to alcohol. Mkp1 deletion in hepatocytes led to increased alcohol induced liver injury, ER stress and inflammation in both sexes.

Conclusion

Hepatocyte Mkp1 plays a significant role in alcohol induced liver injury. Alcohol downregulates Mkp1 expression in hepatocytes in a sex dependent manner and could play a role in sexual dimorphism in increased female susceptibility to alcohol.

Development of novel liver-targeting glucocorticoid prodrugs

Background

Glucocorticoids (GCs) are widely used in the treatment of inflammatory liver diseases and sepsis, but GC's various side effects on extrahepatic tissues limit their clinical benefits. Liver-targeting GC therapy may have multiple advantages over systemic GC therapy. The purpose of this study was to develop novel liver-targeting GC prodrugs as improved treatment for inflammatory liver diseases and sepsis.

Methods

A hydrophilic linker or an ultra-hydrophilic zwitterionic linker carboxylic betaine (CB) was used to bridge cholic acid (CA) and dexamethasone (DEX) to generate transporter-dependent liver-targeting GC prodrugs CA-DEX and the highly hydrophilic CA-CB-DEX. The efficacy of liver-targeting DEX prodrugs and DEX were determined in primary human hepatocytes (PHH), macrophages, human whole blood, and/or mice with sepsis induced by cecal ligation and puncture.

Results

CA-DEX was moderately water soluble, whereas CA-CB-DEX was highly water soluble. CA-CB-DEX and CA-DEX displayed highly transporter-dependent activities in reporter assays. Data mining found marked dysregulation of many GR-target genes important for lipid catabolism, cytoprotection, and inflammation in patients with severe alcoholic hepatitis. These key GR-target genes were similarly and rapidly (within 6 h) induced or down-regulated by CA-CB-DEX and DEX in PHH. CA-CB-DEX had much weaker inhibitory effects than DEX on endotoxin-induced cytokines in mouse macrophages and human whole blood. In contrast, CA-CB-DEX exerted more potent anti-inflammatory effects than DEX in livers of septic mice.

Conclusions

CA-CB-DEX demonstrated good hepatocyte-selectivity in vitro and better anti-inflammatory effects in vivo. Further test of CA-CB-DEX as a novel liver-targeting GC prodrug for inflammatory liver diseases and sepsis is warranted.

SIRT3/6: an amazing challenge and opportunity in the fight against fibrosis and aging

Fibrosis is a typical aging-related pathological process involving almost all organs, including the heart, kidney, liver, lung, and skin. Fibrogenesis is a highly orchestrated process defined by sequences of cellular response and molecular signals mechanisms underlying the disease. In pathophysiologic conditions associated with organ fibrosis, a variety of injurious stimuli such as metabolic disorders, epigenetic changes, and aging may induce the progression of fibrosis. Sirtuins protein is a kind of deacetylase which can regulate cell metabolism and participate in a variety of cell physiological functions. In this review, we outline our current understanding of common principles of fibrogenic mechanisms and the functional role of SIRT3/6 in aging-related fibrosis. In addition, sequences of novel protective strategies have been identified directly or indirectly according to these mechanisms. Here, we highlight the role and biological function of SIRT3/6 focus on aging fibrosis, as well as their inhibitors and activators as novel preventative or therapeutic interventions for aging-related tissue fibrosis.

Mitochondrial stress activates YAP/TAZ through RhoA oxidation to promote liver injury

Yes-associated protein (YAP) and WW domain-containing transcription regulator protein 1 (WWTR1; also known as TAZ) are the main effectors of the Hippo pathway and their dysregulation contributes to diseases in tissues including the liver. Although mitochondria are capable of transmitting signals to change transcriptomic landscape of diseased hepatocytes, such retrograde signaling and the related nuclear machinery are largely unknown. Here, we show that increased YAP activity is associated with mitochondrial stress during liver injury; and this is required for secondary inflammation, promoting hepatocyte death. Mitochondrial stress inducers robustly promoted YAP/TAZ dephosphorylation, nuclear accumulation, and target gene transcription. RNA sequencing revealed that the majority of mitochondrial stress transcripts required YAP/TAZ. Mechanistically, direct oxidation of RhoA by mitochondrial superoxide was responsible for PP2A-mediated YAP/TAZ dephosphorylation providing a novel physiological input for the Hippo pathway. Hepatocyte-specific Yap/Taz ablation suppressed acetaminophen-induced liver injury and blunted transcriptomic changes associated with the pathology. Our observations uncover unappreciated pathway of mitochondrial stress signaling and reveal YAP/TAZ activation as the mechanistic basis for liver injury progression.

The Effects of Lycopene on Modulating Oxidative Stress and Liver Enzymes Levels in Metabolic Syndrome Patients: A Randomised Clinical Trial

OBJECTIVE

The pathogenesis of metabolic syndrome (MetS) complications involves the excessive production of
reactive oxygen species, inflammation, and endothelial dysfunction. Due to Lycopene, a highly unstable structure and
its significant effects on modulating the metabolic system, there is a strong need for a formula that can increase its
stability. The aim of this study was to develop an approach for encapsulating Lycopene and investigate its effects on
inflammatory markers, oxidative stress, and liver enzymes in patients with MetS.
Materials and Methods: This study is a simple randomized, double-blind, objective-based clinical trial that involved
eighty subjects with MetS, who were equally and randomly assigned to two groups: one group received 20 mg of
Lycopene per day for 8 weeks, and the Placebo group followed the same protocol as the Lycopene group but received
a placebo instead of Lycopene. They were called Lycopene and placebo, respectively. During follow-up visits after 4
and 8 weeks, 20 ml of blood was collected for evaluation of liver enzymes and some inflammatory related markers.
Results: Prior to the assignment of volunteers to their respective groups, there were no notable differences in C-reactive
protein (CRP), serum liver enzymes, systolic and diastolic blood pressure, or pro-oxidant-antioxidant balance (PAB)
between the Lycopene and placebo groups. However, our subsequent analysis revealed a significant reduction in the
serum levels of CRP (P=0.001) and PAB (P=0.004) in the group that received Lycopene. Our encapsulated Lycopene
treatment was not associated with a significant difference in serum levels of alanine aminotransferase (ALT), aspartate
transferase (AST), or alkaline phosphatase (ALP) between our two groups.
Conclusion: This study investigated the impact of Lycopene on individuals with MetS, revealing a noteworthy
modulation effect on PAB and inflammation linked to MetS. However, no significant differences was demonstrated in
serum levels of ALT, AST and ALP between the studied group (registration number: IRCT20130507013263N3).

Metformin: update on mechanisms of action on liver diseases

Substantial attention has been paid to the various effects of metformin on liver diseases; the liver is the targeted organ where metformin exerts its antihyperglycemic properties. In non-alcoholic fatty liver disease (NAFLD), studies have shown that metformin affects the ATP/AMP ratio to activate AMPK, subsequently governing lipid metabolism. The latest research showed that low-dose metformin targets the lysosomal AMPK pathway to decrease hepatic triglyceride levels through the PEN2-ATP6AP1 axis in an AMP-independent manner. Metformin regulates caspase-3, eukaryotic initiation factor-2a (eIF2a), and insulin receptor substrate-1 (IRS-1) in palmitate-exposed HepG2 cells, alleviating endoplasmic reticulum (ER) stress. Recent observations highlighted the critical association with intestinal flora, as confirmed by the finding that metformin decreased the relative abundance of Bacteroides fragilis while increasing Akkermansia muciniphila and Bifidobacterium bifidum. The suppression of intestinal farnesoid X receptor (FXR) and the elevation of short-chain fatty acids resulted in the upregulation of tight junction protein and the alleviation of hepatic inflammation induced by lipopolysaccharide (LPS). Additionally, metformin delayed the progression of cirrhosis by regulating the activation and proliferation of hepatic stellate cells (HSCs) via the TGF-β1/Smad3 and succinate-GPR91 pathways. In hepatocellular carcinoma (HCC), metformin impeded the cell cycle and enhanced the curative effect of antitumor medications. Moreover, metformin protects against chemical-induced and drug-induced liver injury (DILI) against hepatotoxic drugs. These findings suggest that metformin may have pharmacological efficacy against liver diseases.

Components of the JNK-MAPK pathway play distinct roles in hepatocellular carcinoma

PURPOSE

Mitogen-activated protein kinases (MAPK), specifically the c-Jun N-terminal kinase (JNK)-MAPK subfamily, play a crucial role in the development of various cancers, including hepatocellular carcinoma (HCC). However, the specific roles of JNK1/2 and their upstream regulators, MKK4/7, in HCC carcinogenesis remain unclear.

METHODS

In this study, we performed differential expression analysis of JNK-MAPK components at both the transcriptome and protein levels using TCGA and HPA databases. We utilized Kaplan-Meier survival plots and receiver operating characteristic (ROC) curve analysis to evaluate the prognostic performance of a risk scoring model based on these components in the TCGA-HCC cohort. Additionally, we conducted immunoblotting, apoptosis analysis with FACS and soft agar assays to investigate the response of JNK-MAPK pathway components to various death stimuli (TRAIL, TNF-α, anisomycin, and etoposide) in HCC cell lines.

RESULTS

JNK1/2 and MKK7 levels were significantly upregulated in HCC samples compared to paracarcinoma tissues, whereas MKK4 was downregulated. ROC analyses suggested that JNK2 and MKK7 may serve as suitable diagnostic genes for HCC, and high JNK2 expression correlated with significantly poorer overall survival. Knockdown of JNK1 enhanced TRAIL-induced apoptosis in hepatoma cells, while JNK2 knockdown reduced TNF-α/cycloheximide (CHX)-and anisomycin-induced apoptosis. Neither JNK1 nor JNK2 knockdown affected etoposide-induced apoptosis. Furthermore, MKK7 knockdown augmented TNF-α/CHX- and TRAIL-induced apoptosis and inhibited colony formation in hepatoma cells.

CONCLUSION

Targeting MKK7, rather than JNK1/2 or MKK4, may be a promising therapeutic strategy to inhibit the JNK-MAPK pathway in HCC therapy.

Perish in the Attempt: Regulated Cell Death in Regenerative and Nonregenerative Tissue

Significance: A cell plays its roles throughout its life span, even during its demise. Regulated cell death (RCD) is one of the key topics in modern biomedical studies. It is considered the main approach for removing stressed and/or damaged cells. Research during the past two decades revealed more roles of RCD, such as coordinating tissue development and driving compensatory proliferation during tissue repair. Recent Advances: Compensatory proliferation, initially identified in primitive organisms during the regeneration of lost tissue, is an evolutionarily conserved process that also functions in mammals. Among various types of RCD, apoptosis is considered the top candidate to induce compensatory proliferation in damaged tissue. Critical Issues: The roles of apoptosis in the recovery of nonregenerative tissue are still vague. The roles of other types of RCD, such as necroptosis and ferroptosis, have not been well characterized in the context of tissue regeneration. Future Directions: In this review article, we attempt to summarize the recent insights on the role of RCD in tissue repair. We focus on apoptosis, with expansion to ferroptosis and necroptosis, in primitive organisms with significant regenerative capacity as well as common mammalian research models. After gathering hints from regenerative tissue, in the second half of the review, we take a notoriously nonregenerative tissue, the myocardium, as an example to discuss the role of RCD in terminally differentiated quiescent cells. Antioxid. Redox Signal. 39, 1053-1069.

In silico identification and biological evaluation of a selective MAP4K4 inhibitor against pancreatic cancer

Inhibiting a specific target in cancer cells and reducing unwanted side effects has become a promising strategy in pancreatic cancer treatment. MAP4K4 is associated with pancreatic cancer development and correlates with poor clinical outcomes. By phosphorylating MKK4, proteins associated with cell apoptosis and survival are translated. Therefore, inhibiting MAP4K4 activity in pancreatic tumours is a new therapeutic strategy. Herein, we performed a structure-based virtual screening to identify MAP4K4 inhibitors and discovered the compound F389-0746 with a potent inhibition (IC₅₀ 120.7 nM). The results of kinase profiling revealed that F389-0746 was highly selective to MAP4K4 and less likely to cause side effects. Results of in vitro experiments showed that F389-0746 significantly suppressed cancer cell growth and viability. Results of in vivo experiments showed that F389-0746 displayed comparable tumour growth inhibition with the group treated with gemcitabine. These findings suggest that F389-0746 has promising potential to be further developed as a novel pancreatic cancer treatment.

Glutaredoxin-1 alleviates acetaminophen-induced liver injury by decreasing its toxic metabolites

Excessive N-acetyl-p-benzoquinone imine (NAPQI) formation is a starting event that triggers oxidative stress and subsequent hepatocyte necrosis in acetaminophen (APAP) overdose caused acute liver failure (ALF). S-glutathionylation is a reversible redox post-translational modification and a prospective mechanism of APAP hepatotoxicity. Glutaredoxin-1 (Glrx1), a glutathione-specific thioltransferase, is a primary enzyme to catalyze deglutathionylation. The objective of this study was to explored whether and how Glrx1 is associated with the development of ALF induced by APAP. The Glrx1 knockout mice (Glrx1-/-) and liver-specific overexpression of Glrx1 (AAV8-Glrx1) mice were produced and underwent APAP-induced ALF. Pirfenidone (PFD), a potential inducer of Glrx1, was administrated preceding APAP to assess its protective effects. Our results revealed that the hepatic total protein S-glutathionylation (PSSG) increased and the Glrx1 level reduced in mice after APAP toxicity. Glrx1-/- mice were more sensitive to APAP overdose, with higher oxidative stress and more toxic metabolites of APAP. This was attributed to Glrx1 deficiency increasing the total hepatic PSSG and the S-glutathionylation of cytochrome p450 3a11 (Cyp3a11), which likely increased the activity of Cyp3a11. Conversely, AAV8-Glrx1 mice were defended against liver damage caused by APAP overdose by inhibiting the S-glutathionylation and activity of Cyp3a11, which reduced the toxic metabolites of APAP and oxidative stress. PFD precede administration upregulated Glrx1 expression and alleviated APAP-induced ALF by decreasing oxidative stress. We have identified the function of Glrx1 mediated PSSG in liver injury caused by APAP overdose. Increasing Glrx1 expression may be investigated for the medical treatment of APAP-caused hepatic injury.

HCV and HCC Tango-Deciphering the Intricate Dance of Disease: A Review Article

Hepatitis C virus (HCV) is a major cause of hepatocellular carcinoma (HCC) accounting for around one-third of all HCC cases. Prolonged inflammation in chronic hepatitis C (CHC), maintained through a variety of pro- and anti-inflammatory mediators, is one of the aspects of carcinogenesis, followed by mitochondrial dysfunction and oxidative stress. Immune response dysfunction including the innate and adaptive immunity also plays a role in the development, as well as in the recurrence of HCC after treatment. Some of the tumor suppressor genes inhibited by the HCV proteins are p53, p73, and retinoblastoma 1. Mutations in the telomerase reverse transcriptase promoter and the oncogene catenin beta 1 are two more important carcinogenic signaling pathways in HCC associated with HCV. Furthermore, in HCV-related HCC, numerous tumor suppressor and seven oncogenic genes are dysregulated by epigenetic changes. Epigenetic regulation of gene expression is considered as a lasting "epigenetic memory", suggesting that HCV-induced changes persist and are associated with liver carcinogenesis even after cure. Epigenetic changes and immune response dysfunction are recognized targets for potential therapy of HCC.

ROS/RNS as molecular signatures of chronic liver diseases

The liver can succumb to oxidant damage during the development of chronic liver diseases. Despite their physiological relevance to hepatic homeostasis, excessive reactive oxygen/nitrogen species (ROS/RNS) production under pathological conditions is detrimental to all liver constituents. Chronic oxidative stress coupled to unresolved inflammation sets in motion the activation of profibrogenic hepatic stellate cells (HSCs) and later pathogenesis of liver fibrosis, cirrhosis, and liver cancer. The liver antioxidant and repair systems, along with autophagic and ferroptotic machineries, are implicated in the onset and trajectory of disease development. In this review, we discuss the ROS/RNS-related mechanisms underlying liver fibrosis of distinct etiologies and highlight preclinical and clinical trials of antifibrotic therapies premised on remediating oxidative/nitrosative stress in hepatocytes or targeting HSC activation.

JNKs protect from cholestatic liver disease progression by modulating Apelin signalling

Background & Aims

Cholestatic liver injury is associated with c-Jun N-terminal kinases (JNK) activation in distinct cell types. Its hepatocyte-specific function during cholestasis, however, has not yet been established. Therefore, in our present study, we investigated the role of JNK1/2 during cholestasis and dissected its hepatocyte-specific function.

Methods

A cohort of patients with primary biliary cholangitis (n = 29) and primary sclerosing cholangitis (n = 37) was examined. Wild-type, hepatocyte-specific knockout mice for Jnk2 (Jnk2Δhepa) or Jnk1 and Jnk2 (Jnk1Δhepa/2Δhepa) were generated. Mice were subjected to bile duct ligation (BDL) or carbon tetrachloride (CCl4) treatment. Finally, Apelin signalling was blocked using a specific inhibitor. As an interventional approach, Jnk1/2 were silenced in wild-type mice using lipid nanoparticles for small interfering RNA delivery.

Results

JNK activation was increased in liver specimens from patients with chronic cholestasis (primary biliary cholangitis and primary sclerosing cholangitis) and in livers of Mdr2-/- and BDL-treated animals. In Jnk1Δhepa/2Δhepa animals, serum transaminases increased after BDL, and liver histology demonstrated enhanced cell death, compensatory proliferation, hepatic fibrogenesis, and inflammation. Furthermore, microarray analysis revealed that hepatocytic Jnk1/2 ablation induces JNK-target genes involved in oxidative stress and Apelin signalling after BDL. Consequently, blocking Apelin signalling attenuated BDL-induced liver injury and fibrosis in Jnk1Δhepa/2Δhepa mice. Finally, we established an interventional small interfering RNA approach of selective Jnk1/2 targeting in hepatocytes in vivo, further demonstrating the essential protective role of Jnk1/2 during cholestasis.

Conclusions

Jnk1 and Jnk2 work together to protect hepatocytes from cholestatic liver disease by controlling Apelin signalling. Dual modification of JNK signalling in hepatocytes is feasible, and enhancing its expression might be an attractive therapeutic approach for cholestatic liver disease.

Impact and Implications

The cell-specific function of Jnk genes during cholestasis has not been explicitly explored. In this study, we showed that combined Jnk1/2, but not Jnk2 deficiency, in hepatocytes exacerbates liver damage and fibrosis by enhancing Apelin signalling, which contributes to cholestasis progression. Combined cell-specific Jnk targeting may be a new molecular strategy for treating cholestatic liver disease.

Enhancement of biochemical and genomic pathways through lycopene-loaded nano-liposomes: Alleviating insulin resistance, hepatic steatosis, and autophagy in obese rats with non-alcoholic fatty liver disease: Involvement of SMO, GLI-1, and PTCH-1 genes

Non-alcoholic fatty liver (NAFL) is a prevalent hepatic disorder of global significance that can give rise to severe complications. This research endeavor delves into the potential of nano-liposomal formulated Lycopene (Lip-Lyco) in averting the development of obesity and insulin resistance, both of which are major underlying factors contributing to NAFL. The investigation further scrutinizes the impact of Lip-Lyco on intricate cellular pathways within the liver tissue of rats induced with NAFL, specifically focusing on the progression of steatosis and fibrosis. To establish an obesity-NAFL model, twenty rats were subjected to a high-fat diet (HFD) for a duration of twelve weeks, after which they received an oral treatment of Lip-Lyco (10mg/kg) for an additional eight weeks. Another group of sixteen non-obese rats were subjected to treatment with or without Lip-Lyco, serving as a control for comparison. Results: The rats on a hypercaloric diet had high body mass index (BMI) and insulin resistance, reflected in disturbed serum adipokines and lipid profiles. Oxidative stress, inflammation, and apoptosis were evident in hepatic tissue, and the autophagic process in hepatocytes was inhibited. Additionally, the hedgehog pathway was activated in the liver tissue of NAFL group. Lip-Lyco was found to counteract all these aspects of NAFL pathogenesis. Lip-Lyco exhibited antioxidant, anti-inflammatory, hypoglycemic, antiapoptotic, autophagy-inducing, and Hedgehog signaling inhibitory effects. This study concludes that Lip-Lyco, a natural compound, has promising therapeutic potential in combating NAFLdisease. However, more experimental and clinical studies are required to confirm the effectiveness of lycopene in treating NAFLdisease.

A comprehensive review on pharmacological, toxicity, and pharmacokinetic properties of phillygenin: Current landscape and future perspectives

Forsythiae Fructus is a traditional Chinese medicine frequently in clinics. It is extensive in the treatment of various inflammation-related diseases and is renowned as 'the holy medicine of sores'. Phillygenin (C21H24O6, PHI) is a component of lignan that has been extracted from Forsythiae Fructus and exhibits notable biological activity. Modern pharmacological studies have confirmed that PHI demonstrates significant activities in the treatment of various diseases, including inflammatory diseases, liver diseases, cancer, bacterial infection and virus infection. Therefore, this review comprehensively summarizes the pharmacological effects of PHI up to June 2023 by searching PubMed, Web of Science, Science Direct, CNKI, and SciFinder databases. According to the data, PHI shows remarkable anti-inflammatory, antioxidant, hepatoprotective, antitumour, antibacterial, antiviral, immunoregulatory, analgesic, antihypertensive and vasodilatory activities. More importantly, NF-κB, MAPK, PI3K/AKT, P2X7R/NLRP3, Nrf2-ARE, JAK/STAT, Ca2+-calcineurin-TFEB, TGF-β/Smads, Notch1 and AMPK/ERK/NF-κB signaling pathways are considered as important molecular targets for PHI to exert these pharmacological activities. Studies of its toxicity and pharmacokinetic properties have shown that PHI has very low toxicity, incomplete absorption in vivo and low oral bioavailability. In addition, the physico-chemical properties, new formulations, derivatives and existing challenges and prospects of PHI are also reviewed and discussed in this paper, aiming to provide direction and rationale for the further development and clinical application of PHI.

Short-term treatment with risperidone ameliorated 1,2-diacetylbenzene-induced liver dysfunction

1,2-Diacetylbenze (C10H10O2, DAB) is a potential inducer or activator of toxic mechanisms. DAB exerts high absorption by the gastrointestinal tract and high blood-brain barrier penetration. However, only the effects of DAB on the central nervous system were reported, with a dearth of evidence of DAB's effects on the liver, which is more susceptible to toxic substances. Risperidone, an atypical antipsychotic drug, has been shown to protect against DAB-induced cognitive impairment in an animal model. Risperidone was found to have little or no effect on the liver after short-term administration. The question of whether risperidone can protect against DAB-induced liver dysfunction, particularly after short-term administration, is unknown. Thus, this study aimed to assess the hepatoprotective effects of risperidone on DAB-induced liver dysfunction in male C57BL/6 mice treated with DAB 5 mg/kg for 1 week and risperidone 0.125-0.25 mg/kg for 2 weeks. After exposure to DAB 5 mg/kg for 1 week, we found that DAB induced liver damage by increasing liver function biomarkers (GGT, ALT, and AST), reactive oxygen species, nitric oxide, and proinflammatory cytokines (IL-1α, IL-1β, IL-6, IL-12, and TNF- α), activating apoptosis (elevated Caspase-3 and Bax levels and reduced Bcl2 level), TLR4/JNK/NF-κB, Jak2/Stat5 pathways, and suppressing Jak2/Stat3 and IRS1/PI3K/AKT/MDM2 pathways. After a 2-week course of treatment, risperidone was able to lessen these effects; the higher dose (0.25 mg/kg) appeared to be more effective than the lower dose (0.125 mg/kg). To strengthen findings from in vivo analysis, in silico analysis also found three targets (Stat3, Caspase-3, AKT, IL-1β), two miRNAs (miR-26b-5p and miR-34a-5p), two transcription factors (NFKB1 and NFKB2), and numerous pathways ("AGE-RAGE signaling pathway in diabetic complications", "hepatitis B", "alcoholic liver disease", "apoptosis", and "liver cirrhosis") as the key molecular processes involved in the pathogenesis of DAB-induced liver damage and targeted by risperidone. The physicochemical characteristics and pharmacokinetics of DAB and risperidone also support the toxic effects of DAB and the beneficial properties of risperidone in the liver. In conclusion, these findings reflect the therapeutic effects of risperidone on DAB-induced liver dysfunction after 1 week and 2 weeks exposure to DAB and risperidone, respectively.

MKP1 promotes nonalcoholic steatohepatitis by suppressing AMPK activity through LKB1 nuclear retention

Nonalcoholic steatohepatitis (NASH) is triggered by hepatocyte death through activation of caspase 6, as a result of decreased adenosine monophosphate (AMP)-activated protein kinase-alpha (AMPKα) activity. Increased hepatocellular death promotes inflammation which drives hepatic fibrosis. We show that the nuclear-localized mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP1) is upregulated in NASH patients and in NASH diet fed male mice. The focus of this work is to investigate whether and how MKP1 is involved in the development of NASH. Under NASH conditions increased oxidative stress, induces MKP1 expression leading to nuclear p38 MAPK dephosphorylation and decreases liver kinase B1 (LKB1) phosphorylation at a site required to promote LKB1 nuclear exit. Hepatic deletion of MKP1 in NASH diet fed male mice releases nuclear LKB1 into the cytoplasm to activate AMPKα and prevents hepatocellular death, inflammation and NASH. Hence, nuclear-localized MKP1-p38 MAPK-LKB1 signaling is required to suppress AMPKα which triggers hepatocyte death and the development of NASH.

Knockdown of AK142426 suppresses M2 macrophage polarization and inflammation in peritoneal fibrosis via binding to c-Jun

BACKGROUND

Peritoneal fibrosis is a common complication of peritoneal dialysis, which may lead to ultrafiltration failure and ultimately treatment discontinuation. LncRNAs participate in many biological processes during tumorigenesis. We investigated the role of AK142426 in peritoneal fibrosis.

METHODS

The AK142426 level in peritoneal dialysis (PD) fluid was detected by quantitative real-time-PCR assay. The M2 macrophage distribution was determined by flow cytometry. The inflammatory cytokines of TNF-α and TGF-β1 were measured by ELISA assay. The direct interaction between AK142426 and c-Jun was evaluated by RNA pull-down assay. In addition, the c-Jun and fibrosis related proteins were assessed by western blot analysis.

RESULTS

The PD-induced peritoneal fibrosis mouse model was successfully established. More importantly, PD treatment induced M2 macrophage polarization and the inflammation in PD fluid, which might be associated with exosome transmission. Fortunately, AK142426 was observed to be upregulated in PD fluid. Mechanically, knockdown of AK142426 suppressed M2 macrophage polarization and inflammation. Furthermore, AK142426 could upregulate c-Jun through binding c-Jun protein. In rescue experiments, overexpression of c-Jun could partially abolish the inhibitory effect of sh-AK142426 on the activation of M2 macrophages and inflammation. Consistently, knockdown of AK142426 alleviated peritoneal fibrosis in vivo.

CONCLUSIONS

This study demonstrated that knockdown of AK142426 suppressed M2 macrophage polarization and inflammation in peritoneal fibrosis via binding to c-Jun, suggesting that AK142426 might be a promising therapeutic target for patients of peritoneal fibrosis.

c-Jun N-terminal kinase activation contributes to improving low temperature tolerance via regulating apoptosis in the Pacific white shrimp Penaeus vannamei

Temperature is an essential environmental factor for the survival of aquatic animals. Low temperature stress can induce mitochondria to produce excessive ROS and free radicals, and destroy homeostasis. c-Jun N-terminal kinase (JNK) is involved in regulating various physiological processes, including inflammatory responses, cell cycle, reproduction, and apoptosis. Here, we investigated the mechanism of ROS/JNK pathway under low temperature stress both in vitro and in vivo. In this study, transcriptome analysis revealed that apoptosis, autophagy, calcium channel, and antioxidant were involved in the mediation of low temperature tolerance in Pacific white shrimp (penaeus vannamei). PvJNK was activated in response to low temperature stress. Treatments with different temperature caused oxidative stress as demonstrated by increased intensity of the ROS indicator H2DCF-DA, and induced apoptosis as confirmed by indicator FITC. Pretreatment with N-acetylcysteine, an ROS scavenger, attenuated low temperature induced apoptosis, and inhibited the expression of PvJNK. In addition, we demonstrate that mediator PvJNK translocated to nuclear through interacting with PvRheb. By using flow cytometry, inhibiting PvJNK can increase the expression of apoptosis related genes, accelerate tissue damage, and induce ROS and cell apoptosis. The ultimate inhibition of PvJNK accelerates the mortality of shrimp under low temperature stress. Overall, these findings suggest that during low temperature stress, PvJNK was activated by ROS to regulates apoptosis via interacting with PvRheb to promote PvJNK into the nucleus and to improve low temperature tolerance of shrimp.

Autophagy, Oxidative Stress, and Alcoholic Liver Disease: A Systematic Review and Potential Clinical Applications

Ethanol consumption triggers oxidative stress by generating reactive oxygen species (ROS) through its metabolites. This process leads to steatosis and liver inflammation, which are critical for the development of alcoholic liver disease (ALD). Autophagy is a regulated dynamic process that sequesters damaged and excess cytoplasmic organelles for lysosomal degradation and may counteract the harmful effects of ROS-induced oxidative stress. These effects include hepatotoxicity, mitochondrial damage, steatosis, endoplasmic reticulum stress, inflammation, and iron overload. In liver diseases, particularly ALD, macroautophagy has been implicated as a protective mechanism in hepatocytes, although it does not appear to play the same role in stellate cells. Beyond the liver, autophagy may also mitigate the harmful effects of alcohol on other organs, thereby providing an additional layer of protection against ALD. This protective potential is further supported by studies showing that drugs that interact with autophagy, such as rapamycin, can prevent ALD development in animal models. This systematic review presents a comprehensive analysis of the literature, focusing on the role of autophagy in oxidative stress regulation, its involvement in organ-organ crosstalk relevant to ALD, and the potential of autophagy-targeting therapeutic strategies.

MKP1 promotes nonalcoholic steatohepatitis by suppressing AMPK activity through LKB1 nuclear retention

Nonalcoholic steatohepatitis (NASH) is triggered by hepatocyte death through activation of caspase 6, as a result of decreased adenosine monophosphate (AMP)-activated protein kinase-alpha (AMPKα) activity. Increased hepatocellular death promotes inflammation which drives hepatic fibrosis. We show that the nuclear-localized mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP1) is upregulated in NASH patients and in NASH diet fed mice. The focus of this work was to investigate whether and how MKP1 is involved in the development of NASH. Under NASH conditions increased oxidative stress, induces MKP1 expression leading to nuclear p38 MAPK dephosphorylation and decreased liver kinase B1 (LKB1) phosphorylation at a site required to promote LKB1 nuclear exit. Hepatic deletion of MKP1 in NASH diet fed mice released nuclear LKB1 into the cytoplasm to activate AMPKα and prevent hepatocellular death, inflammation and NASH. Hence, nuclear-localized MKP1-p38 MAPK-LKB1 signaling is required to suppress AMPKα which triggers hepatocyte death and the development of NASH.

Interleukin-1 family cytokines in liver cell death: a new therapeutic target for liver diseases

INTRODUCTION

Liver cell death represents a basic biological process regulating the progression of liver diseases via distinct mechanisms. Accumulating evidence has uncovered participation of interleukin (IL)-1 family cytokines in liver cell death. Upon activation of cell death induced by hepatotoxic stimuli, IL1 family cytokines released by hepatic dead cells stimulate recruitment of immune cells, which in turn influence inflammation and subsequent liver injury, thus highlighting their potential as therapeutic targets in liver diseases. Enhancing our comprehension of mechanisms underlying IL1 family cytokine signaling in cell death responses could pave the way for novel therapeutic interventions aimed at addressing liver cell death-related liver pathologies.

AREAS COVERED

This review summarizes the recent findings reported in preclinical and clinical studies on mechanisms of liver cell death, alongside participation of IL1 family members consisting of IL1α, ILβ, IL18, and IL33 in liver cell death and their significant implications in liver diseases.

EXPERT OPINION

Discovery of new and innovative therapeutic approaches for liver diseases will need close cooperation between fundamental and clinical scientists to better understand the multi-step processes behind IL1 family cytokines' contributions to liver cell death.

The impact and role of identified long noncoding RNAs in nonalcoholic fatty liver disease: A narrative review

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide, but its mechanism and pathophysiology remain unclear. Long noncoding RNAs (lncRNAs) may exert a vital influence on regulating various biological functions in NAFLD.

METHODS

The databases such as Google Scholar, PubMed, and Medline were searched using the following keywords: nonalcoholic fatty liver disease, nonalcoholic fatty liver disease, NAFLD, nonalcoholic steatohepatitis, nonalcoholic steatohepatitis, NASH, long noncoding RNAs, and lncRNAs. Considering the titles and abstracts, unrelated studies were excluded. The authors evaluated the full texts of the remaining studies.

RESULTS

We summarized the current knowledge of lncRNAs and the main signaling pathways of lncRNAs involved in NAFLD explored in recent years. As a heterogeneous group of noncoding RNAs (ncRNAs), lncRNAs play crucial roles in biological processes underlying the pathophysiology of NAFLD. The mechanisms, particularly those associated with the regulation of the expression and activities of lncRNAs, play important roles in NAFLD.

CONCLUSION

A better comprehension of the mechanism controlled by lncRNAs in NAFLD is necessary for the identification of novel therapeutic targets for drug development and improved, noninvasive methods for diagnosis.

Tumor progression locus 2 (TPL2): A Cot-plicated progression from inflammation to chronic liver disease

The cytoplasmic protein tumor progression locus 2 (TPL2), also known as cancer Osaka thyroid (Cot), or MAP3K8, is thought to have a significant role in a variety of cancers and illnesses and it is a key component in the activation pathway for the expression of inflammatory mediators. Despite the tight connection between inflammation and TPL2, its function has not been extensively studied in chronic liver disease (CLD), a major cause of morbidity and mortality worldwide. Here, we analyze more in detail the significance of TPL2 in CLD to shed light on the pathological and molecular transduction pattern of TPL2 during the progression of CLD. This might result in important advancements and enable progress in the diagnosis and treatment of CLD.

Overexpression of HSF2 binding protein suppresses endoplasmic reticulum stress via regulating subcellular localization of CDC73 in hepatocytes

BACKGROUND

Endoplasmic reticulum (ER) stress plays an important role in the occurrence and development of various liver diseases. However, there are no effective prevention and treatment strategies. We aimed to determine the role of heat shock factor 2 binding protein (HSF2BP) in ER stress.

METHODS

HSF2BP expression in mice and cultured hepatocytes was measured during ER stress induced by tunicamycin, and its importance in ER stress was evaluated in hepatocyte-specific HSF2BP transgenic (TG) and knockout (KO) mice. The effects and mechanisms of HSF2BP on ER stress were further probed in hepatic ischemia-reperfusion (I/R) injury.

RESULTS

HSF2BP expression was significantly upregulated during tunicamycin-induced ER stress in mice and cultured hepatocytes. Liver injury and ER stress were reduced in HSF2BP overexpressing mice after treating with tunicamycin, but were aggravated in HSF2BP knockout mice compared to the controls. In hepatic I/R injury, HSF2BP expression was significantly upregulated, and HSF2BP overexpressing mice had reduced liver injury and inflammation. These improvements were associated with ER stress inhibition. However, these results were reversed in hepatocyte-specific HSF2BP knockout mice. HSF2BP overexpression increased cytoplasmic CDC73 levels and inhibited the JNK signaling pathway. CDC73 knockdown using siRNA eliminated the protection exerted by HSF2BP overexpression in hypoxia/reoxygenation (H/R)-induced ER stress in hepatocytes.

CONCLUSION

HSF2BP is a previously uncharacterized regulatory factor in ER stress-likely acts by regulating CDC73 subcellular localization. The feasibility of HSF2BP-targeted treatment in ER stress-related liver disease deserves future research.

Understanding the Potential Role of Nanotechnology in Liver Fibrosis: A Paradigm in Therapeutics

The liver is a vital organ that plays a crucial role in the physiological operation of the human body. The liver controls the body's detoxification processes as well as the storage and breakdown of red blood cells, plasma protein and hormone production, and red blood cell destruction; therefore, it is vulnerable to their harmful effects, making it more prone to illness. The most frequent complications of chronic liver conditions include cirrhosis, fatty liver, liver fibrosis, hepatitis, and illnesses brought on by alcohol and drugs. Hepatic fibrosis involves the activation of hepatic stellate cells to cause persistent liver damage through the accumulation of cytosolic matrix proteins. The purpose of this review is to educate a concise discussion of the epidemiology of chronic liver disease, the pathogenesis and pathophysiology of liver fibrosis, the symptoms of liver fibrosis progression and regression, the clinical evaluation of liver fibrosis and the research into nanotechnology-based synthetic and herbal treatments for the liver fibrosis is summarized in this article. The herbal remedies summarized in this review article include epigallocathechin-3-gallate, silymarin, oxymatrine, curcumin, tetrandrine, glycyrrhetinic acid, salvianolic acid, plumbagin, Scutellaria baicalnsis Georgi, astragalosides, hawthorn extract, and andrographolides.

Taurine protects against perfluorooctanoic acid-induced hepatotoxicity via inhibition of oxidative stress, inflammatory, and apoptotic pathways

We are constantly encountering with low doses of chemicals in everyday life rather than toxic doses at a time. So, ongoing low-dose exposures of environmental chemicals commonly encountered are very likely to cause an adverse health effects. Perfluorooctanoic acid (PFOA) is frequently used for production of an array of consumer products and industrial processes. The present study evaluated the underlying mechanisms of PFOA-induced liver damage and also potential protection by taurine. Male Wistar rats were exposed to PFOA alone and in combination with taurine (25, 50, and 100 mg/kg/day) by gavage for 4 weeks. Liver function tests as well as histopathological examinations were studied. Also, oxidative stress markers, mitochondrial function, and nitric oxide (NO) production in liver tissues were measured. In addition, the expression of apoptosis-related genes (caspase-3, Bax, and Bcl-2), inflammation-associated genes (TNF-α, IL-6, NF-B), and c-Jun-N-terminal kinase (JNK) were evaluated. Taurine significantly reversed serum biochemical and histopathological alterations in the liver tissue following exposure to PFOA (10 mg/kg/day). Similarly, taurine alleviated mitochondrial oxidative damage-induced by PFOA in the liver tissue. An increased Bcl2: Bax ratio with decrees in the expression level of caspase-3, and decreased expression of inflammatory markers (TNF-α and IL-6), NF-B, and JNK were also observed following the administration of taurine. These findings suggest a protective role of taurine against PFOA-induced hepatotoxicity via the inhibition of oxidative stress, inflammation, and apoptosis.

Gene polymorphisms of inflammatory factors in liver cirrhosis

Introduction: Studies on the association between gene polymorphisms of various inflammatory factors and liver cirrhosis have been inconsistent. The purpose of this study was to comprehensively summarize the available evidence on the association between gene polymorphisms of inflammatory factors and liver cirrhosis through a systematic review. Methods: We searched databases of PubMed, EMBASE, Web of Science, and the Cochrane Library for relevant articles published from building databases to 25 September 2022. A systematic review and meta-analysis were performed to investigate the association between gene polymorphisms of various inflammatory factors and liver cirrhosis. Odds ratios (OR) and 95% confidence intervals (CI) were used to assess the strength of association. Results: A total of 43 articles were included in the systematic review and of them, 22 articles were included in the meta-analysis. The gene polymorphisms of IL-10-1082 GA + AA vs. GG (OR = 1.43, 95% CI = 1.12-1.83), IL-10-1082 AA vs. GG (OR = 2.03, 95% CI = 1.36-3.02), IL-18 -137 GG vs. CC (OR = 3.84, 95% CI = 1.29-11.40), TGF-β1 -509 T vs. C (OR = 2.52, 95% CI = 1.42-4.48), and IFN-γ +874 T vs. A (OR = 1.98, 95% CI = 1.32-2.98) were associated with liver cirrhosis significantly and no association was observed in other gene polymorphisms included in the meta-analysis. The review of inflammatory factors gene polymorphisms that were only reported by a single study indicated 19 gene polymorphisms were risk factors and 4 gene polymorphisms were protective factors for liver cirrhosis, while the association between other 27 gene polymorphisms and liver cirrhosis were not statistically significant. Discussion: This study suggests that IL-10 -1082G/A, IL-18 -137G/C, TGF-β1 -509T/C, and IFN-γ +874T/A were potentially associated with the risk of liver cirrhosis susceptibility. These findings may provide comprehensive evidence for genetic susceptibility and immunogenetic pathology of liver cirrhosis.

Paeoniflorin Protects against Acetaminophen-Induced Liver Injury in Mice via JNK Signaling Pathway

BACKGROUND

Drug-induced liver injury (DILI), represented by acetaminophen (APAP), is a common cause of acute liver failure in clinics. Paeoniflorin (PF) has been proven to demonstrate a significant hepatoprotective effect. However, it is still unclear whether it can be a potential agent against hepatotoxicity induced by APAP. This study aimed to explore the preventive and therapeutic effects and mechanisms of PF on APAP-induced liver injury.

METHODS

Different doses of PF (50, 100, and 200 mg/kg) were given to C57BL/6 male mice for five consecutive days. After 12 h of APAP (250 mg/kg i.p.) treatment, blood and liver tissues were collected and isolated for detection.

RESULTS

The results showed that the therapeutic effects of PF on APAP mice were presented in the downregulation of the content of serum indices and significantly improved hepatic tissue edema and inflammatory infiltration. Meanwhile, PF reduces the level of the mitochondrial metabolic enzyme. Ulteriorly, it was found that PF has a downregulating effect on the apoptotic reaction and could inhibit the protein expression of CYP2E1/JNK signaling, which in turn reduces the damage of APAP.

CONCLUSION

Our findings showed that PF acted as a protective agent against APAP-induced hepatotoxicity by inhibiting JNK-related signals, suggesting a novel insight into treating APAP-induced liver injury.

Ablation of Tumor Necrosis Factor Alpha Receptor 1 Signaling Blunts Steatohepatitis in Peroxisome Proliferator Activated Receptor α-Deficient Mice

Tumor necrosis factor -alpha (TNFα) is strongly associated with fatty liver disease (i.e, hepatosteatosis). Cytokine production has been thought of as a consequence of hepatic lipid accumulation which becomes a critical factor in the development of chronic liver pathologies as well as insulin resistance. The purpose of this study was to test the hypothesis that TNFα directly regulates lipid metabolism in liver in the mutant peroxisome-proliferator activated receptor-alpha (PPARα^-/-) mouse model with robust hepatic lipid accumulation. At 10 weeks of age, TNFα and TNF receptor 1 expression are increased in livers of PPARα^-/- mice compared to wild type. PPARα^-/- mice were then crossed with mice lacking the receptor for TNFα receptor 1 (TNFR1^-/-). Wild type, PPARα^-/-, TNFR1^-/-, PPARα^-/- x TNFR1^-/- mice were housed on ad-libitum standard chow diet for up to 40 weeks. Increases in hepatic lipid and liver injury and metabolic disruption associated with PPARα ablation were largely blunted when PPARα^-/- mice were crossed with TNFR1^-/- mice. These data support the hypothesis that TNFR1 signaling is critical for accumulation of lipid in liver. Therapies that reduce pro-inflammatory responses, namely TNFα, could have important clinical implications to reduce hepatosteatosis and progression of severe liver disease.

Narrative Review: Glucocorticoids in Alcoholic Hepatitis—Benefits, Side Effects, and Mechanisms

Alcoholic hepatitis is a major health and economic burden worldwide. Glucocorticoids (GCs) are the only first-line drugs recommended to treat severe alcoholic hepatitis (sAH), with limited short-term efficacy and significant side effects. In this review, I summarize the major benefits and side effects of GC therapy in sAH and the potential underlying mechanisms. The review of the literature and data mining clearly indicate that the hepatic signaling of glucocorticoid receptor (GR) is markedly impaired in sAH patients. The impaired GR signaling causes hepatic down-regulation of genes essential for gluconeogenesis, lipid catabolism, cytoprotection, and anti-inflammation in sAH patients. The efficacy of GCs in sAH may be compromised by GC resistance and/or GC’s extrahepatic side effects, particularly the side effects of intestinal epithelial GR on gut permeability and inflammation in AH. Prednisolone, a major GC used for sAH, activates both the GR and mineralocorticoid receptor (MR). When GC non-responsiveness occurs in sAH patients, the activation of MR by prednisolone might increase the risk of alcohol abuse, liver fibrosis, and acute kidney injury. To improve the GC therapy of sAH, the effort should be focused on developing the biomarker(s) for GC responsiveness, liver-targeting GR agonists, and strategies to overcome GC non-responsiveness and prevent alcohol relapse in sAH patients.

Mitochondrial stress induces AREG expression and epigenomic remodeling through c-JUN and YAP-mediated enhancer activation

Nucleus–mitochondria crosstalk is essential for cellular and organismal homeostasis. Although anterograde (nucleus-to-mitochondria) pathways have been well characterized, retrograde (mitochondria-to-nucleus) pathways remain to be clarified. Here, we found that mitochondrial dysfunction triggered a retrograde signaling via unique transcriptional and chromatin factors in hepatic cells. Our transcriptomic analysis revealed that the loss of mitochondrial transcription factor A led to mitochondrial dysfunction and dramatically induced expression of amphiregulin (AREG) and other secretory protein genes. AREG expression was also induced by various mitochondria stressors and was upregulated in murine liver injury models, suggesting that AREG expression is a hallmark of mitochondrial damage. Using epigenomic and informatic approaches, we identified that mitochondrial dysfunction-responsive enhancers of AREG gene were activated by c-JUN/YAP1/TEAD axis and were repressed by chromatin remodeler BRG1. Furthermore, while mitochondrial dysfunction-activated enhancers were enriched with JUN and TEAD binding motifs, the repressed enhancers possessed the binding motifs for hepatocyte nuclear factor 4α, suggesting that both stress responsible and cell type-specific enhancers were reprogrammed. Our study revealed that c-JUN and YAP1-mediated enhancer activation shapes the mitochondrial stress-responsive phenotype, which may shift from metabolism to stress adaptation including protein secretion under such stressed conditions.

Non-Coding RNAs in Hepatocellular Carcinoma

Liver cancer ranks as the fourth leading cause of cancer-related deaths. Despite extensive research efforts aiming to evaluate the biological mechanisms underlying hepatocellular carcinoma (HCC) development, little has been translated towards new diagnostic and treatment options for HCC patients. Historically, the focus has been centered on coding RNAs and their respective proteins. However, significant advances in sequencing and RNA detection technologies have shifted the research focus towards non-coding RNAs (ncRNA), as well as their impact on HCC development and progression. A number of studies reported complex post-transcriptional interactions between various ncRNA and coding RNA molecules. These interactions offer insights into the role of ncRNAs in both the known pathways leading to oncogenesis, such as dysregulation of p53, and lesser-known mechanisms, such as small nucleolar RNA methylation. Studies investigating these mechanisms have identified prevalent ncRNA changes in microRNAs, snoRNAs, and long non-coding RNAs that can both pre- and post-translationally regulate key factors in HCC progression. In this review, we present relevant publications describing ncRNAs to summarize the impact of different ncRNA species on liver cancer development and progression and to evaluate recent attempts at clinical translation.

Hepatic interleukin-1 receptor type 1 signalling regulates insulin sensitivity in the early phases of nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is associated with hepatic as well as systemic insulin resistance even in the absence of type 2 diabetes. The extent and pathways through which hepatic inflammation modulates insulin sensitivity in NAFLD are only partially understood. We explored the contribution of hepatic interleukin (IL)-1 signalling in a novel conditional knockout mouse model and expand the knowledge on this signalling pathway with regard to its liver-specific functions.

METHODS

A high-fat, high-carbohydrate diet (HFD) over 12 weeks was used in male hepatocyte-specific IL-1 receptor type 1 (IL-1R1) knockout mice (Il1r1Hep-/- ) and wild-type (WT) littermates.

RESULTS

Both genotypes developed an obese phenotype and accompanying macrovesicular hepatic steatosis. In contrast to WT mice, microvesicular steatosis and ballooning injury was less pronounced in HFD-fed Il1r1Hep-/- mice, and alanine aminotransferase remained in the normal range. This was paralleled by the suppression of injurious and proinflammatory hepatic c-Jun N-terminal kinases and extracellular signal-regulated kinases signalling, stable peroxisome proliferator activated receptor gamma coactivator-1alpha and farnesoid X receptor-alpha expression and preservation of mitochondrial function. Strikingly, despite HFD-feeding Il1r1Hep-/- mice remained highly insulin sensitive as indicated by lower insulin levels, homeostatic model assessment for insulin resistance, higher glucose tolerance, more stable hepatic insulin signalling cascade, and less adipose tissue inflammation compared to the WT.

CONCLUSIONS

The current data highlights that hepatocyte IL-1R1 contributes to hepatic and extrahepatic insulin resistance. Future liver-directed therapies in NAFLD could have effects on insulin sensitivity when improving hepatic inflammation and IL-1R1 signalling.

Mechanism and Therapeutic Targets of c-Jun-N-Terminal Kinases Activation in Nonalcoholic Fatty Liver Disease

Non-alcoholic fatty liver (NAFL) is the most common chronic liver disease. Activation of mitogen-activated kinases (MAPK) cascade, which leads to c-Jun N-terminal kinase (JNK) activation occurs in the liver in response to the nutritional and metabolic stress. The aberrant activation of MAPKs, especially c-Jun-N-terminal kinases (JNKs), leads to unwanted genetic and epi-genetic modifications in addition to the metabolic stress adaptation in hepatocytes. A mechanism of sustained P-JNK activation was identified in acute and chronic liver diseases, suggesting an important role of aberrant JNK activation in NASH. Therefore, modulation of JNK activation, rather than targeting JNK protein levels, is a plausible therapeutic application for the treatment of chronic liver disease.

A virulence factor as a therapeutic: the probiotic Enterococcus faecium SF68 arginine deiminase inhibits innate immune signaling pathways

The probiotic bacterial strain Enterococcus faecium SF68 has been shown to alleviate symptoms of intestinal inflammation in human clinical trials and animal feed supplementation studies. To identify factors involved in immunomodulatory effects on host cells, E. faecium SF68 and other commensal and clinical Enterococcus isolates were screened using intestinal epithelial cell lines harboring reporter fusions for NF-κB and JNK(AP-1) activation to determine the responses of host cell innate immune signaling pathways when challenged with bacterial protein and cell components. Cell-free, whole-cell lysates of E. faecium SF68 showed a reversible, inhibitory effect on both NF-κB and JNK(AP-1) signaling pathway activation in intestinal epithelial cells and abrogated the response to bacterial and other Toll-like receptor (TLR) ligands. The inhibitory effect was species-specific, and was not observed for E. avium, E. gallinarum, or E. casseliflavus. Screening of protein fractions of E. faecium SF68 lysates yielded an active fraction containing a prominent protein identified as arginine deiminase (ADI). The E. faecium SF68 arcA gene encoding arginine deiminase was cloned and introduced into E. avium where it conferred the same NF-_κB inhibitory effects on intestinal epithelial cells as seen for E. faecium SF68. Our results indicate that the arginine deiminase of E. faecium SF68 is responsible for inhibition of host cell NF-κB and JNK(AP-1) pathway activation, and is likely to be responsible for the anti-inflammatory and immunomodulatory effects observed in prior clinical human and animal trials. The implications for the use of this probiotic strain for preventive and therapeutic purposes are discussed.

The versatility of macrophage heterogeneity in liver fibrosis

Liver fibrosis is a highly conserved wound healing response to liver injury, characterized by excessive deposition of extracellular matrix (ECM) in the liver which might lead to loss of normal functions. In most cases, many types of insult could damage hepatic parenchymal cells like hepatocytes and/or cholangiocytes, and persistent injury might lead to initiation of fibrosis. This process is accompanied by amplified inflammatory responses, with immune cells especially macrophages recruited to the site of injury and activated, in order to orchestrate the process of wound healing and tissue repair. In the liver, both resident macrophages and recruited macrophages could activate interstitial cells which are responsible for ECM synthesis by producing a variety of cytokines and chemokines, modulate local microenvironment, and participate in the regulation of fibrosis. In this review, we will focus on the main pathological characteristics of liver fibrosis, as well as the heterogeneity on origin, polarization and functions of hepatic macrophages in the setting of liver fibrosis and their underlying mechanisms, which opens new perspectives for the treatment of liver fibrosis.

Activin B promotes the initiation and progression of liver fibrosis

The role of activin B, a transforming growth factor β (TGFβ) superfamily cytokine, in liver health and disease is largely unknown. We aimed to investigate whether activin B modulates liver fibrogenesis. Liver and serum activin B, along with its analog activin A, were analyzed in patients with liver fibrosis from different etiologies and in mouse acute and chronic liver injury models. Activin B, activin A, or both was immunologically neutralized in mice with progressive or established carbon tetrachloride (CCl₄ )-induced liver fibrosis. Hepatic and circulating activin B was increased in human patients with liver fibrosis caused by several liver diseases. In mice, hepatic and circulating activin B exhibited persistent elevation following the onset of several types of liver injury, whereas activin A displayed transient increases. The results revealed a close correlation of activin B with liver injury regardless of etiology and species. Injured hepatocytes produced excessive activin B. Neutralizing activin B largely prevented, as well as improved, CCl₄ -induced liver fibrosis, which was augmented by co-neutralizing activin A. Mechanistically, activin B mediated the activation of c-Jun-N-terminal kinase (JNK), the induction of inducible nitric oxide synthase (iNOS) expression, and the maintenance of poly (ADP-ribose) polymerase 1 (PARP1) expression in injured livers. Moreover, activin B directly induced a profibrotic expression profile in hepatic stellate cells (HSCs) and stimulated these cells to form a septa structure. Conclusions: We demonstrate that activin B, cooperating with activin A, mediates the activation or expression of JNK, iNOS, and PARP1 and the activation of HSCs, driving the initiation and progression of liver fibrosis.

Deficiency in Inactive Rhomboid Protein2 (iRhom2) Alleviates Alcoholic Liver Fibrosis by Suppressing Inflammation and Oxidative Stress

Chronic alcohol exposure can lead to liver pathology relating to inflammation and oxidative stress, which are two of the major factors in the incidence of liver fibrosis and even liver cancer. The underlying molecular mechanisms regarding hepatic lesions associated with alcohol are not fully understood. Considering that the recently identified iRhom2 is a key pathogenic mediator of inflammation, we performed in vitro and in vivo experiments to explore its regulatory role in alcohol-induced liver fibrosis. We found that iRhom2 knockout significantly inhibited alcohol-induced inflammatory responses in vitro, including elevated expressions of inflammatory cytokines (IL-1β, IL-6, IL-18, and TNF-α) and genes associated with inflammatory signaling pathways, such as TACE (tumor necrosis factor-alpha converting enzyme), TNFR1 (tumor necrosis factor receptor 1), and TNFR2, as well as the activation of NF-κB. The in vivo results confirmed that long-term alcohol exposure leads to hepatocyte damage and fibrous accumulation. In this pathological process, the expression of iRhom2 is promoted to activate the TACE/NF-κB signaling pathway, leading to inflammatory responses. Furthermore, the deletion of iRhom2 blocks the TACE/NF-κB signaling pathway and reduces liver damage and fibrosis caused by alcohol. Additionally, the activation of the JNK/Nrf2/HO-1 signaling pathway caused by alcohol exposure was also noted in vitro and in vivo. In the same way, knockout or deleting iRhom2 blocked the JNK/Nrf2/HO-1 signaling pathway to regulate the oxidative stress. Therefore, we contend that iRhom2 is a key regulator that promotes inflammatory responses and regulates oxidative stress in alcoholic liver fibrosis lesions. We posit that iRhom2 is potentially a new therapeutic target for alcoholic liver fibrosis.