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Background: Nonalcoholic fatty liver disease (NAFLD) has developed as a leading public wellness challenge as a result of changes in dietary patterns. Unfortunately, there is still a lack of effective pharmacotherapy methods for NAFLD. Wang's empirical formula (WSF) has demonstrated considerable clinical efficacy in treating metabolic disorders for years. Nevertheless, the protective effect of WSF against NAFLD and its underlying mechanism remains poorly understood. Methods: The NAFLD model was established using a 17-week high-sucrose and high-fat (HSHF) diet with 32 ICR mice. In assessing the therapeutic efficacy of WSF on NAFLD, we detected changes in body weight, viscera weight, biomarkers of glycolipid metabolism in serum and liver, transaminase levels and histopathology of liver with H&E and Oil Red O staining after oral administration. The chemical components in WSF were extensively identified and gathered utilizing the HPLC-Q-TOF/MS system, database mining from HMDB, MassBank, and TCMSP databases, alongside literature searches from CNKI, Wanfang and VIP databases. The forecast of network pharmacology approach was then utilized to investigate the probable mechanisms by which WSF improves NAFLD based on the performance of prospective target identification and pathway enrichment analysis. Besides, molecular docking was also conducted for the verification of combination activities between active components of WSF and core proteins related to NAFLD. In final, validation experiments of obtained pathways were conducted through ELISA, immunohistochemistry (IHC), and western blot (WB) analysis. Results: Pharmacodynamic outcomes indicated that WSF intervention effectively mitigated obesity, fat accumulation in organs, lipid metabolism disorders, abnormal transaminase levels and liver pathology injury in NAFLD mice (P < 0.05, 0.01). A total of 72 existent ingredients of WSF were acquired by HPLC-Q-TOF/MS and database, and 254 common targets (11.6% in total targets) of NAFLD and WSF were identified. Network pharmacology revealed that WSF presses NAFLD via modulating TNF, IL6, AKT1, IL1B, PTGS2 (COX2), and other targets, and the probable pathways were primarily inflammatory signaling pathways, as confirmed by molecular docking. Molecular biology experiments further conformed that WSF could decrease levels of inflammatory factors like IL-1β, IL-6 and TNF-α (P < 0.01) and expression of TLR4, NF-κB and COX-2 (P < 0.05, 0.01) in the liver. Conclusion: WSF treatment effectively protects against lipid metabolism disorders and liver inflammation injury in HSHF diet-induced NAFLD mice, and its molecular mechanism might be via suppressing the TLR4/NF-κB/COX-2 inflammatory pathway to reduce the release of inflammatory cytokines in the liver. [ABSTRACT FROM AUTHOR]

Introduction: Mitochondrial membrane potential (MMP) and mitochondrial mass (MM) affect mitochondrial function and lymphocyte activation, but few studies on HBV infection exist. This study aimed to investigate the regulatory mechanism of mitochondrial dysfunction during HBV infection and its clinical significance by analyzing the alterations of MM and MMPlow in peripheral blood immune cells. Methods: The study enrolled 90 participants, including healthy volunteers(HC) and patients with HBV infection, HBV patients were divided into chronic hepatitis B patients (CHB) and liver cirrhosis (LC) according to the study, and CHB was also divided into an inflammation group and a non-inflammation group. Flow cytometry was used to analyze the changes of MM and MMPlow in peripheral blood immune cells. These analyses were correlated with the presence of CHB and LC and indexes related to liver inflammation. Results: The study revealed significant variations in the percentage of MMPlow and MM of CD8+T cells associated with the progression of the disease. The MMPlow percentage of CD8+T cells in the LC group exhibited a notable decrease compared to the HC group and CHB groups. Moreover, MMPlow of CD8+T cells demonstrated potential in distinguishing CHB and LC (AUC=0.7341, P=0.0032). Furthermore, in exploring the link between mitochondrial function of immune cells and liver inflammation, the study found a negative correlation between the MMPlow ratio of CD4+T and CD8+T cells and AST (p=0.0039 and P=0.0070, r=-0.4405 and r=-0.4146), while the MM of CD8+T cells displayed a positive correlation with AST (p=0.0013, r=0.4865). In CHB patients with normal ALT but liver inflammation detected on B-scan ultrasonography, a significant decrease was observed in the MMPlow percentage of CD8+T (66.13 ± 14.27), CD56+NK(57.77 ± 17.40) and CD4-CD8-T (61.98 ± 15.98) cells. Furthermore, it was also found that the percentage of MMPlow in CD4-CD8-T cells could serve as an indicator for early liver inflammation and injury (AUC=0.8408, P=0.0052). Discussion: In this study, we conducted a systematic analysis of the percentage of lymphocyte MMPlow and MM in various stages of HBV infection. Our findings revealed a correlation between MMPlow and MM and early liver inflammation, as well as the progression of the infection. This study marked the first demonstration of the clinical diagnostic value of MMPlow and MM in HBV infection. Furthermore, this was the first study to discuss the mitochondria of lymphocytes and liver inflammation in HBV infection. It enhanced the understanding of the role of T cells in liver inflammation, and elucidated potential markers for the early detection of liver injury and clinical cirrhosis. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the anti-inflammatory effect of black cumin seed oil (BCSO) and its nanoemulsion on lipopolysaccharide (LPS)-induced liver injury in mice. Methods: LPS-induced acute liver injury mouse model was used to evaluate the effects of BCSO and its nanoemulsion formulation on liver function. Hepatic inflammatory markers including Toll-like receptor 4 (TLR4), interleukin(IL)-1β, heme-oxygenase 1, BAX, and BCL-2 were assessed using real-time PCR. Additionally, protein levels of reduced glutathione, tumor necrosis factor-α, and IL-6 were measured using ELISA, and histological analysis was performed. Indomethacin was used as a standard positive control for comparison. Results: BCSO reduced LPS-induced liver injury and exhibited strong anti-inflammatory effects by downregulating the expression of TLR4, IL-1β, IL-6, tumor necrosis factor-α, and heme-oxygenase 1. Additionally, BCSO demonstrated antioxidant properties by increasing reduced glutathione protein levels and decreasing key apoptotic markers BAX and BCL-2 in hepatocytes. The nanoemulsion formulation further enhanced these anti-inflammatory, antioxidant, and anti-apoptotic effects, and histological examination confirmed this effect. Combining BCSO with indomethacin at a lower dose improved efficacy, thereby reducing its potential side effects. Conclusions: The investigation reveals the anti-inflammatory impact of BCSO and its nanoemulsion formulation on LPS-induced liver oxidative stress, inflammation, and apoptosis. [ABSTRACT FROM AUTHOR]

Background: Hepatic macrophages play an indispensable role in liver pathophysiology, serving as key orchestrators of both liver injury and repair processes. ATG16L1 (autophagy‐related 16 like 1) has emerged as a novel and critical autophagy marker. In macrophages, ATG16L1 assumes a particularly crucial role. The current understanding of how macrophage ATG16L1 regulates liver inflammation in the context of liver fibrosis is unclear. Methods: This study included clinical patient samples of liver fibrosis and established a murine model with myeloid‐specific Atg16l1 knockout, creating a mouse model of liver fibrosis. Employing RNA sequencing, we sought to elucidate the mechanisms of macrophage ATG16L1 in liver fibrosis by identifying critical signaling pathways. To assess the influence of macrophage ATG16L1 on hepatocyte apoptosis and hepatic stellate cell (HSC) activation, we constructed a dedicated culture system. Ultimately, the introduction of mice with myeloid‐specific Atg16l1 knock‐in substantiated the protective role of myeloid‐specific Atg16l1 against inflammatory signaling, hepatocyte apoptosis, and activation of HSCs. Results: An upregulation of the ATG16L1 signal was observed in the liver tissues of patients with liver fibrosis and in fibrotic mice, predominantly localized to hepatic macrophages. In Atg16l1ΔMφ mice afflicted with liver fibrosis, we detected exacerbated liver damage, evidenced by heightened inflammatory signal expression, increased hepatocyte apoptosis, and enhanced activation of HSCs. The absence of macrophage Atg16l1 was found to result in elevated TNF receptor‐associated factor 1 (TRAF1) signaling, triggering inflammatory activation, intensifying hepatocyte apoptosis, and facilitating HSC activation through the transforming growth factor beta 1 (TGF‐β1) signaling. The detrimental effects of macrophage Atg16l1 depletion were demonstrated to be mitigated upon Atg16l1 reintroduction. Conclusions: This research delved into the mechanisms by which the macrophage ATG16L1 signal influences inflammatory signaling, hepatocyte apoptosis, and activation of HSCs in liver fibrosis. Consequently, it offers theoretical substantiation and an experimental groundwork for the identification of biological targets for therapeutic intervention in liver fibrosis. [ABSTRACT FROM AUTHOR]

Abstract Background Nonalcoholic fatty liver disease (NAFLD) has developed as a leading public wellness challenge as a result of changes in dietary patterns. Unfortunately, there is still a lack of effective pharmacotherapy methods for NAFLD. Wang’s empirical formula (WSF) has demonstrated considerable clinical efficacy in treating metabolic disorders for years. Nevertheless, the protective effect of WSF against NAFLD and its underlying mechanism remains poorly understood. Methods The NAFLD model was established using a 17-week high-sucrose and high-fat (HSHF) diet with 32 ICR mice. In assessing the therapeutic efficacy of WSF on NAFLD, we detected changes in body weight, viscera weight, biomarkers of glycolipid metabolism in serum and liver, transaminase levels and histopathology of liver with H&E and Oil Red O staining after oral administration. The chemical components in WSF were extensively identified and gathered utilizing the HPLC-Q-TOF/MS system, database mining from HMDB, MassBank, and TCMSP databases, alongside literature searches from CNKI, Wanfang and VIP databases. The forecast of network pharmacology approach was then utilized to investigate the probable mechanisms by which WSF improves NAFLD based on the performance of prospective target identification and pathway enrichment analysis. Besides, molecular docking was also conducted for the verification of combination activities between active components of WSF and core proteins related to NAFLD. In final, validation experiments of obtained pathways were conducted through ELISA, immunohistochemistry (IHC), and western blot (WB) analysis. Results Pharmacodynamic outcomes indicated that WSF intervention effectively mitigated obesity, fat accumulation in organs, lipid metabolism disorders, abnormal transaminase levels and liver pathology injury in NAFLD mice (P

Objective: To evaluate the anti-inflammatory effect of black cumin seed oil (BCSO) and its nanoemulsion on lipopolysaccharide (LPS)-induced liver injury in mice. Methods: LPS-induced acute liver injury mouse model was used to evaluate the effects of BCSO and its nanoemulsion formulation on liver function. Hepatic inflammatory markers including Toll-like receptor 4 (TLR4), interleukin(IL)-1β, heme-oxygenase 1, BAX, and BCL-2 were assessed using real-time PCR. Additionally, protein levels of reduced glutathione, tumor necrosis factor-α, and IL-6 were measured using ELISA, and histological analysis was performed. Indomethacin was used as a standard positive control for comparison. Results: BCSO reduced LPS-induced liver injury and exhibited strong anti-inflammatory effects by downregulating the expression of TLR4, IL-1β, IL-6, tumor necrosis factor-α, and heme-oxygenase 1. Additionally, BCSO demonstrated antioxidant properties by increasing reduced glutathione protein levels and decreasing key apoptotic markers BAX and BCL-2 in hepatocytes. The nanoemulsion formulation further enhanced these anti-inflammatory, antioxidant, and anti-apoptotic effects, and histological examination confirmed this effect. Combining BCSO with indomethacin at a lower dose improved efficacy, thereby reducing its potential side effects. Conclusions: The investigation reveals the anti-inflammatory impact of BCSO and its nanoemulsion formulation on LPS-induced liver oxidative stress, inflammation, and apoptosis.

BACKGROUND & AIMS: Receptor-interacting serine/threonine-protein kinase 3 (RIPK3) is a central player in triggering necroptotic cell death. However, whether macrophage RIPK3 may regulate NOD1-dependent inflammation and calcineurin/transient receptor potential cation channel subfamily M member 7 (TRPM7)-induced hepatocyte death in oxidative stress-induced liver inflammatory injury remains elusive. METHODS: A mouse model of hepatic ischaemia-reperfusion (IR) injury, the primary hepatocytes, and bone marrow-derived macrophages were used in the myeloid-specific RIPK3 knockout (RIPK3M-KO) and RIPK3-proficient (RIPK3FL/FL) mice. RESULTS: RIPK3M-KO diminished IR stress-induced liver damage with reduced serum alanine aminotransferase/aspartate aminotransferase levels, macrophage/neutrophil infiltration, and pro-inflammatory mediators compared with the RIPK3FL/FL controls. IR stress activated RIPK3, inositol-requiring transmembrane kinase/endoribonuclease 1α (IRE1α), x-box binding protein 1 (XBP1), nucleotide-binding oligomerisation domain-containing protein 1 (NOD1), NF-κB, forkhead box O1 (Foxo1), calcineurin A, and TRPM7 in ischaemic livers. Conversely, RIPK3M-KO depressed IRE1α, XBP1, NOD1, calcineurin A, and TRPM7 activation with reduced serum tumour necrosis factor α (TNF-α) levels. Moreover, Foxo1M-KO alleviated IR-induced liver injury with reduced NOD1 and TRPM7 expression. Interestingly, chromatin immunoprecipitation coupled with massively parallel sequencing revealed that macrophage Foxo1 colocalised with XBP1 and activated its target gene Zc3h15 (zinc finger CCCH domain-containing protein 15). Activating macrophage XBP1 enhanced Zc3h15, NOD1, and NF-κB activity. However, disruption of macrophage Zc3h15 inhibited NOD1 and hepatocyte calcineurin/TRPM7 activation, with reduced reactive oxygen species production and lactate dehydrogenase release after macrophage/hepatocyte coculture. Furthermore, adoptive transfer of Zc3h15-expressing macrophages in RIPK3M-KO mice augmented IR-triggered liver inflammation and cell death. CONCLUSIONS: Macrophage RIPK3 activates the IRE1α-XBP1 pathway and Foxo1 signalling in IR-stress livers. The XBP1-Foxo1 interaction is essential for modulating target gene Zc3h15 function, which is crucial for the control of NOD1 and calcineurin-mediated TRPM7 activation. XBP1 functions as a transcriptional coactivator of Foxo1 in regulating NOD1-driven liver inflammation and calcineurin/TRPM7-induced cell death. Our findings underscore a novel role of macrophage RIPK3 in stress-induced liver inflammation and cell death, implying the potential therapeutic targets in liver inflammatory diseases. IMPACT AND IMPLICATIONS: Macrophage RIPK3 promotes NOD1-dependent inflammation and calcineurin/TRPM7-induced cell death cascade by triggering the XBP1-Foxo1 axis and its target gene Zc3h15, which is crucial for activating NOD1 and calcineurin/TRPM7 function, implying the potential therapeutic targets in stress-induced liver inflammatory injury.

Abstract Background Chronic hepatitis B virus (HBV) infection remains a serious health issue, and determining the optimal time for antiviral therapy is challenging. We aimed to assess liver histological changes in patients with HBeAg-positive chronic hepatitis B (CHB) and those with HBeAg-negative CHB who had persistently normal alanine aminotransferase and to determine the association between significant liver injury and various clinical parameters. Methods We retrospectively included, in this study, 339 treatment-naïve patients with chronic HBV infections who had persistently normal alanine aminotransferase and underwent liver biopsy from 2013 to 2023. Histologic assessment was based on the Metavir scoring system to evaluate the association between clinical characteristics and the severity of liver inflammation and fibrosis. Results Among the included participants, 138 were HBeAg-positive and 201 were HBeAg-negative. Lower hepatitis B surface antigen (HBsAg) (P = 0.003) and higher aspartate aminotransferase (AST) (P = 0.002) levels were associated with significant necroinflammation, whereas increasing age (P = 0.004) and lower HBV DNA (P

Liver inflammation is frequently linked to oxidative stress and dysregulation of bile acid and fatty acid metabolism. This review focuses on the farnesoid X receptor (FXR), a critical regulator of bile acid homeostasis, and its interaction with the nuclear factor erythroid 2-related factor 2 (Nrf2), a key modulator of cellular defense against oxidative stress. The review explores the interplay between FXR and Nrf2 in liver inflammatory diseases, highlighting the potential therapeutic effects of natural FXR agonists. Specifically, compounds such as auraptene, cafestol, curcumin, fargesone A, hesperidin, lycopene, oleanolic acid, resveratrol, rutin, ursolic acid, and withaferin A are reviewed for their ability to modulate both the FXR and Nrf2 pathways. This article discusses their potential to alleviate liver inflammation, oxidative stress, and damage in diseases such as metabolic-associated fatty liver disease (MAFLD), cholestatic liver injury, and viral hepatitis. In addition, we address the molecular mechanisms driving liver inflammation, including oxidative stress, immune responses, and bile acid accumulation, while also summarizing relevant experimental models. This review emphasizes the promising therapeutic potential of targeting both the Nrf2 and FXR pathways using natural compounds, paving the way for future treatments for liver diseases. Finally, the limitations of the clinical application were indicated, and further research directions were proposed. [ABSTRACT FROM AUTHOR]

Background: Chronic hepatitis B virus (HBV) infection remains a serious health issue, and determining the optimal time for antiviral therapy is challenging. We aimed to assess liver histological changes in patients with HBeAg-positive chronic hepatitis B (CHB) and those with HBeAg-negative CHB who had persistently normal alanine aminotransferase and to determine the association between significant liver injury and various clinical parameters. Methods: We retrospectively included, in this study, 339 treatment-naïve patients with chronic HBV infections who had persistently normal alanine aminotransferase and underwent liver biopsy from 2013 to 2023. Histologic assessment was based on the Metavir scoring system to evaluate the association between clinical characteristics and the severity of liver inflammation and fibrosis. Results: Among the included participants, 138 were HBeAg-positive and 201 were HBeAg-negative. Lower hepatitis B surface antigen (HBsAg) (P = 0.003) and higher aspartate aminotransferase (AST) (P = 0.002) levels were associated with significant necroinflammation, whereas increasing age (P = 0.004) and lower HBV DNA (P < 0.001) levels were associated with significant fibrosis in HBeAg-positive patients with normal ALT levels. Higher HBV-DNA (P = 0.001) and AST levels(P < 0.001) were associated with significant necroinflammation, and higher AST(P < 0.001) levels were associated with significant fibrosis in HBeAg-negative patients. Conclusions: A substantial proportion of patients with HBV infection who had normal ALT presented significant liver injury. HBsAg and AST were independent predictive factors for evaluating inflammation, while HBV DNA load and age were independent predictive factors for evaluating fibrosis in the HBeAg-positive group. HBV DNA load and AST were independent predictive factors for evaluating inflammation, while AST were independent predictive factors for evaluating fibrosis in the HBeAg-negative group. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate the effects of licorice processing of different Evodiae Fructus (EF) specifications on liver inflammation and oxidative stress associated with the intestinal mucosal microbiota. Materials and methods: The 25 Kunming mice were divided into control (MCN), raw small-flowered Evodiae Fructus (MRSEF), raw medium-flowered EF (MRMEF), licorice-processed small-flowered EF (MLSEF), and licorice-processed medium-flowered EF (MLSEF) groups. The EF intervention groups were given different specifications of EF extract solutions by gavage. After 21 days, indices of liver inflammation and oxidative stress and intestinal mucosal microbiota were measured in mice. Results: Compared with the MCN, malondialdehyde (MDA), tumor necrosis factor-a (TNF-a), and interleukin-6 (IL-6) levels were significantly increased in the MRMEF. Although the trends of oxidative stress and inflammatory indexes in the MLSEF and MLMEF were consistent with those in the raw EF groups, the changes were smaller than those in the raw EF groups. Compared to the raw EF groups, the MLSEF and MLMEF showed closer approximations of metabolic function to the MCN. The abundance of Corynebacterium in MRMEF was significantly lower than that in the MCN, and it was not significantly different from the MCN after licorice processing. The probiotic Candidatus Arthromitus was enriched in the MLSEF. The probiotic Lactobacillus was enriched in the MLMEF. Correlation analysis revealed significant negative correlations between IL-1b, some metabolic functions and Corynebacterium. Conclusion: The effects of medium-flowered EF on oxidative stress and inflammatory factors in the liver of mice were stronger than those of small- flowered EF. The licorice processing can reduce this difference by modulating the abundance of Corynebacterium and intestinal mucosal metabolic function. [ABSTRACT FROM AUTHOR]

Hepatitis B Virus (HBV) is a stealthy and insidious pathogen capable of inducing chronic necro-inflammatory liver disease and hepatocellular carcinoma (HCC), resulting in over one million deaths worldwide per year. The traditional understanding of Chronic Hepatitis B (CHB) progression has focused on the complex interplay among ongoing virus replication, aberrant immune responses, and liver pathogenesis. However, the dynamic progression and crucial factors involved in the transition from HBV infection to immune activation and intrahepatic inflammation remain elusive. Recent insights have illuminated HBV's exploitation of the sodium taurocholate co-transporting polypeptide (NTCP) and manipulation of the cholesterol transport system shared between macrophages and hepatocytes for viral entry. These discoveries deepen our understanding of HBV as a virus that hijacks hepatocyte metabolism. Moreover, hepatic niche macrophages exhibit significant phenotypic and functional diversity, zonal characteristics, and play essential roles, either in maintaining liver homeostasis or contributing to the pathogenesis of chronic liver diseases. Therefore, we underscore recent revelations concerning the importance of hepatic niche macrophages in the context of viral hepatitis. This review particularly emphasizes the significant role of HBV-induced metabolic changes in hepatic macrophages as a key factor in the transition from viral infection to immune activation, ultimately culminating in liver inflammation. These metabolic alterations in hepatic macrophages offer promising targets for therapeutic interventions and serve as valuable early warning indicators, shedding light on the disease progression. [ABSTRACT FROM AUTHOR]

Background: Routine liver function tests capture information about the metabolic and inflammatory condition of the liver, but we lack sensitive biomarkers of early hepatocyte stress. In humans, soluble CD46 (sCD46) levels in blood were recently identified as an accurate biomarker of hepatic steatosis. Here, we explore the diagnostic utility of sCD46 in other liver diseases. Methods: We developed, optimised and validated an ELISA that facilitates measurements of human sCD46 in plasma, serum and culture supernatants. Then, we analysed mechanisms that lead to the release of sCD46 and identified its role in various hepatic stress conditions. Results: We discovered that prostaglandin E2 (PGE2) drives upregulation of matrix metalloproteinase (MMP)-1 in fat-loaded hepatocytes, leading to proteolytic shedding of CD46. We further found that sCD46 release was increased by viral, toxic and hypoxic stresses. Conclusions: sCD46 appears to be a promising biomarker with potential applications in the detection of early liver diseases or monitoring therapeutic responses, which could complement established diagnostic algorithms because sCD46 release is uniquely responsive to hepatocyte stress.

Inflammation responses have identified as a key mediator of in various liver diseases with high morbidity and mortality. cGAS-STING signalling is essential in innate immunity since it triggers release of type I interferons and various of proinflammatory cytokines. The potential connection between cGAS-STING pathway and liver inflammatory diseases has recently been reported widely. In our review, the impact of cGAS-STING on liver inflammation and regulatory mechanism are summarized. Furthermore, many inhibitors of cGAS-STING signalling as promising agents to cure liver inflammation are also explored in detail. A comprehensive knowledge of molecular mechanisms of cGAS-STING signalling in liver inflammation is vital for exploring novel treatments and providing recommendations and perspectives for future utilization.

IntroductionMitochondrial membrane potential (MMP) and mitochondrial mass (MM) affect mitochondrial function and lymphocyte activation, but few studies on HBV infection exist. This study aimed to investigate the regulatory mechanism of mitochondrial dysfunction during HBV infection and its clinical significance by analyzing the alterations of MM and MMPlow in peripheral blood immune cells.MethodsThe study enrolled 90 participants, including healthy volunteers(HC) and patients with HBV infection, HBV patients were divided into chronic hepatitis B patients (CHB) and liver cirrhosis (LC) according to the study, and CHB was also divided into an inflammation group and a non-inflammation group. Flow cytometry was used to analyze the changes of MM and MMPlow in peripheral blood immune cells. These analyses were correlated with the presence of CHB and LC and indexes related to liver inflammation.ResultsThe study revealed significant variations in the percentage of MMPlow and MM of CD8+T cells associated with the progression of the disease. The MMPlow percentage of CD8+T cells in the LC group exhibited a notable decrease compared to the HC group and CHB groups. Moreover, MMPlow of CD8+T cells demonstrated potential in distinguishing CHB and LC (AUC=0.7341, P=0.0032). Furthermore, in exploring the link between mitochondrial function of immune cells and liver inflammation, the study found a negative correlation between the MMPlow ratio of CD4+T and CD8+T cells and AST (p=0.0039 and P=0.0070, r=-0.4405 and r=-0.4146), while the MM of CD8+T cells displayed a positive correlation with AST (p=0.0013, r=0.4865). In CHB patients with normal ALT but liver inflammation detected on B-scan ultrasonography, a significant decrease was observed in the MMPlow percentage of CD8+T (66.13 ± 14.27), CD56+NK(57.77 ± 17.40) and CD4-CD8-T (61.98 ± 15.98) cells. Furthermore, it was also found that the percentage of MMPlow in CD4-CD8-T cells could serve as an indicator for early liver inflammation and injury (AUC=0.8408, P=0.0052).DiscussionIn this study, we conducted a systematic analysis of the percentage of lymphocyte MMPlow and MM in various stages of HBV infection. Our findings revealed a correlation between MMPlow and MM and early liver inflammation, as well as the progression of the infection. This study marked the first demonstration of the clinical diagnostic value of MMPlow and MM in HBV infection. Furthermore, this was the first study to discuss the mitochondria of lymphocytes and liver inflammation in HBV infection. It enhanced the understanding of the role of T cells in liver inflammation, and elucidated potential markers for the early detection of liver injury and clinical cirrhosis.

Epidemiological studies have demonstrated exposure to cadmium ion (Cd2+) is significantly associated with the incidence and aggravation of nonalcoholic fatty liver disease (NAFLD) to non-alcoholic steatohepatitis (NASH). Cd2+ exposure could alter lipid metabolism, and changed lipid metabolites are significantly associated with NASH. Arachidonic acid (ArA) is an omega-6 polyunsaturated fatty acid. Promotion of ArA synthesis and profile changes by Cd2+ exposure potentially to cause NAFLD. ArA metabolism pathway has been identified to enrich in Cd2+ exposure-facilitated NASH. ArA could be generation an impressive metabolic profile through mainly three pathways, including Cyclooxygenases (COX), Lipoxygenases (LOX) and Cytochrome P450 (CYP450) pathway. However, the functions of these metabolites and underlying mechanism in hepatic inflammation are still not clear. In present study, by integrative transcriptomics and metabolomics analysis, we identified that the fatty acid metabolic process and the pro-inflammatory NF-κB signaling pathway were enriched in Cd2+-regulated differentially expressed genes (DEGs) and Cd2+-altered differential metabolites, such as, fatty acid biosynthesis, degradation, and ArA metabolism. The metabolites levels of LOX pathway products 5-HETE and leukotriene C4 (LTC4), and COX catalytic product prostaglandin D2 (PGD2) were significantly elevated in Cd2+ exposed mouse livers. 5-HETE, LTC4, and PGD2 were significantly positive correlated with NF-κB signaling. In addition, the synthase of 20-Hydroxyeicosatetraenoic acid (20-HETE), CYP450 gene 4 family (CYP4A32), was also involved in NF-κB signaling network. Results from both in vitro and in vivo proved that Cd2+ exposure increased ArA metabolite to PGD2 and 20-HETE, and upregulated the mRNA level of their catalytic enzyme PGDS and CYP4A32. Cd2+-induced ArA metabolite to PGD2 and 20-HETE promoted activation of TLR4/IκBα/NF-κB signaling and pro-inflammatory of hepatocytes. Our study explores novel molecular mechanism of Cd2+ exposure-aggravated liver diseases and provides potential novel targets for in hepatic inflammatory treatments and prevention.

Abstract The chemokine (CCL)-chemokine receptor (CCR2) interaction, importantly CCL2-CCR2, involved in the intrahepatic recruitment of monocytes upon liver injury promotes liver fibrosis. CCL2-CCR2 antagonism using Cenicriviroc (CVC) showed promising results in several preclinical studies. Unfortunately, CVC failed in phase III clinical trials due to lack of efficacy to treat liver fibrosis. Lack of efficacy could be attributed to the fact that macrophages are also involved in disease resolution by secreting matrix metalloproteinases (MMPs) to degrade extracellular matrix (ECM), thereby inhibiting hepatic stellate cells (HSCs) activation. HSCs are the key pathogenic cell types in liver fibrosis that secrete excessive amounts of ECM causing liver stiffening and liver dysfunction. Knowing the detrimental role of intrahepatic monocyte recruitment, ECM, and HSCs activation during liver injury, we hypothesize that combining CVC and MMP (MMP1) could reverse liver fibrosis. We evaluated the effects of CVC, MMP1 and CVC + MMP1 in vitro and in vivo in CCl4-induced liver injury mouse model. We observed that CVC + MMP1 inhibited macrophage migration, and TGF-β induced collagen-I expression in fibroblasts in vitro. In vivo, MMP1 + CVC significantly inhibited normalized liver weights, and improved liver function without any adverse effects. Moreover, MMP1 + CVC inhibited monocyte infiltration and liver inflammation as confirmed by F4/80 and CD11b staining, and TNFα gene expression. MMP1 + CVC also ameliorated liver fibrogenesis via inhibiting HSCs activation as assessed by collagen-I staining and collagen-I and α-SMA mRNA expression. In conclusion, we demonstrated that a combination therapeutic approach by combining CVC and MMP1 to inhibit intrahepatic monocyte recruitment and increasing collagen degradation respectively ameliorate liver inflammation and fibrosis.

Abstract Background Changes in plasma protein glycosylation are known to functionally affect proteins and to associate with liver diseases, including cirrhosis and hepatocellular carcinoma. Autoimmune hepatitis (AIH) is a liver disease characterized by liver inflammation and raised serum levels of IgG, and is difficult to distinguish from other liver diseases. The aim of this study was to examine plasma and IgG-specific N-glycosylation in AIH and compare it with healthy controls and other liver diseases. Methods In this cross-sectional cohort study, total plasma N-glycosylation and IgG Fc glycosylation analysis was performed by mass spectrometry for 66 AIH patients, 60 age- and sex-matched healthy controls, 31 primary biliary cholangitis patients, 10 primary sclerosing cholangitis patients, 30 non-alcoholic fatty liver disease patients and 74 patients with viral or alcoholic hepatitis. A total of 121 glycans were quantified per individual. Associations between glycosylation traits and AIH were investigated as compared to healthy controls and other liver diseases. Results Glycan traits bisection (OR: 3.78 [1.88–9.35], p-value: 5.88 × 10− 3), tetraantennary sialylation per galactose (A4GS) (OR: 2.88 [1.75–5.16], p-value: 1.63 × 10− 3), IgG1 galactosylation (OR: 0.35 [0.2–0.58], p-value: 3.47 × 10− 5) and hybrid type glycans (OR: 2.73 [1.67–4.89], p-value: 2.31 × 10− 3) were found as discriminators between AIH and healthy controls. High A4GS differentiated AIH from other liver diseases, while bisection associated with cirrhosis severity. Conclusions Compared to other liver diseases, AIH shows distinctively high A4GS levels in plasma, with potential implications on glycoprotein function and clearance. Plasma-derived glycosylation has potential to be used as a diagnostic marker for AIH in the future. This may alleviate the need for a liver biopsy at diagnosis. Glycosidic changes should be investigated further in longitudinal studies and may be used for diagnostic and monitoring purposes in the future.

We have previously documented that in liver cells, the multifunctional protein scaffold p62/SQSTM1 is closely associated with IκBα, an inhibitor of the transcriptional activator NF-κB. Such an intimate p62-IκBα association we now document leads to a marked 18-fold proteolytic IκBα-stabilization, enabling its nuclear entry and termination of the NF-κB-activation cycle. In p62-/--cells, such termination is abrogated resulting in the nuclear persistence and prolonged activation of NF-κB following inflammatory stimuli. Utilizing various approaches both classic (structural deletion, site-directed mutagenesis) as well as novel (in-cell chemical crosslinking), coupled with proteomic analyses, we have defined the precise structural hotspots of p62-IκBα association. Accordingly, we have identified such IκBα hotspots to reside around N-terminal (K38, K47, and K67) and C-terminal (K238/C239) residues in its fifth ankyrin repeat domain. These sites interact with two hotspots in p62: One in its PB-1 subdomain around K13, and the other comprised of a positively charged patch (R183/R186/K187/K189) between its ZZ- and TB-subdomains. APEX proximity analyses upon IκBα-cotransfection of cells with and without p62 have enabled the characterization of the p62 influence on IκBα-protein-protein interactions. Interestingly, consistent with p62's capacity to proteolytically stabilize IκBα, its presence greatly impaired IκBα's interactions with various 20S/26S proteasomal subunits. Furthermore, consistent with p62 interaction with IκBα on an interface opposite to that of its NF-κB-interacting interface, p62 failed to significantly affect IκBα-NF-κB interactions. These collective findings together with the known dynamic p62 nucleocytoplasmic shuttling leads us to speculate that it may be involved in "piggy-back" nuclear transport of IκBα following its NF-κB-elicited transcriptional activation and de novo synthesis, required for termination of the NF-κB-activation cycle. Consequently, mice carrying a liver-specific deletion of p62-residues 68 to 252 reveal age-dependent-enhanced liver inflammation. Our findings reveal yet another mode of p62-mediated pathophysiologically relevant regulation of NF-κB.

The chemokine (CCL)-chemokine receptor (CCR2) interaction, importantly CCL2-CCR2, involved in the intrahepatic recruitment of monocytes upon liver injury promotes liver fibrosis. CCL2-CCR2 antagonism using Cenicriviroc (CVC) showed promising results in several preclinical studies. Unfortunately, CVC failed in phase III clinical trials due to lack of efficacy to treat liver fibrosis. Lack of efficacy could be attributed to the fact that macrophages are also involved in disease resolution by secreting matrix metalloproteinases (MMPs) to degrade extracellular matrix (ECM), thereby inhibiting hepatic stellate cells (HSCs) activation. HSCs are the key pathogenic cell types in liver fibrosis that secrete excessive amounts of ECM causing liver stiffening and liver dysfunction. Knowing the detrimental role of intrahepatic monocyte recruitment, ECM, and HSCs activation during liver injury, we hypothesize that combining CVC and MMP (MMP1) could reverse liver fibrosis. We evaluated the effects of CVC, MMP1 and CVC + MMP1 in vitro and in vivo in CCl4-induced liver injury mouse model. We observed that CVC + MMP1 inhibited macrophage migration, and TGF-β induced collagen-I expression in fibroblasts in vitro. In vivo, MMP1 + CVC significantly inhibited normalized liver weights, and improved liver function without any adverse effects. Moreover, MMP1 + CVC inhibited monocyte infiltration and liver inflammation as confirmed by F4/80 and CD11b staining, and TNFα gene expression. MMP1 + CVC also ameliorated liver fibrogenesis via inhibiting HSCs activation as assessed by collagen-I staining and collagen-I and α-SMA mRNA expression. In conclusion, we demonstrated that a combination therapeutic approach by combining CVC and MMP1 to inhibit intrahepatic monocyte recruitment and increasing collagen degradation respectively ameliorate liver inflammation and fibrosis. [ABSTRACT FROM AUTHOR]

Nod-like receptor family pyrin-containing protein 3 (NLRP3) inflammasome plays a pathologic role in metabolic dysfunction-associated steatohepatitis (MASH), but the molecular mechanism regulating the NLRP3 inflammasome activation in hepatocellular lipotoxicity remains largely unknown. Bromodomain-containing protein 4 (BRD4) has emerged as a key epigenetic reader of acetylated lysine residues in enhancer regions that control the transcription of key genes. The aim of this study is to investigate if and how BRD4 regulated the NLRP3 inflammasome activation and pyroptosis in MASH. Using the AML12 and primary mouse hepatocytes stimulated by palmitic acid (PA) as an in vitro model of hepatocellular lipotoxicity, we found that targeting BRD4 by genetic knockdown or a selective BRD4 inhibitor MS417 protected against hepatosteatosis; and this protective effect was attributed to inhibiting the activation of NLRP3 inflammasome and reducing the expression of Caspase-1, gasdermin D (GSDMD), interleukin (IL)-1β and IL-6. Moreover, BRD4 inhibition limited the voltage-dependent anion channel-1 (VDAC1) expression and oligomerization in PA-treated AML12 hepatocytes, thereby suppressing the NLRP3 inflammasome activation. Additionally, the expression of BRD4 enhanced in MASH livers of humans. Mechanistically, BRD4 was upregulated during hepatocellular lipotoxicity that in turn modulated the active epigenetic mark H3K27ac at the promoter regions of the Vdac and Gsdmd genes, thereby enhancing the expression of VDAC and GSDMD. Altogether, our data provide novel insights into epigenetic mechanisms underlying BRD4 activating the NLRP3 inflammasome and promoting GSDMD-mediated pyroptosis in hepatocellular lipotoxicity. Thus, BRD4 might serve as a novel therapeutic target for the treatment of MASH. [ABSTRACT FROM AUTHOR]

The rs72613567:TA polymorphism in 17-beta hydroxysteroid dehydrogenase 13 (HSD17B13) has been found to reduce the progression from steatosis to metabolic dysfunction-associated steatohepatitis (MASH). In this study, we sought to define the pathogenic role of HSD17B13 in triggering liver inflammation. Here, we demonstrate that HSD17B13 forms liquid–liquid phase separation (LLPS) around lipid droplets in the livers of MASH patients. The dimerization of HSD17B13 supports the LLPS formation and promotes its enzymatic function. HSD17B13 LLPS increases the biosynthesis of platelet activating factor (PAF), which in turn promotes fibrinogen synthesis and leukocyte adhesion. Blockade of the PAF receptor or STAT3 pathway inhibits the fibrinogen synthesis and leukocyte adhesion. Importantly, adeno-associated viral-mediated xeno-expression of human HSD17B13 exacerbates western diet/carbon tetrachloride-induced liver inflammation in Hsd17b13−/− mice. In conclusion, our results suggest that HSD17B13 LLPS triggers liver inflammation by promoting PAF-mediated leukocyte adhesion, and targeting HSD17B13 phase transition could be a promising therapeutic approach for treating hepatic inflammation in chronic liver disease. [ABSTRACT FROM AUTHOR]

Background: Changes in plasma protein glycosylation are known to functionally affect proteins and to associate with liver diseases, including cirrhosis and hepatocellular carcinoma. Autoimmune hepatitis (AIH) is a liver disease characterized by liver inflammation and raised serum levels of IgG, and is difficult to distinguish from other liver diseases. The aim of this study was to examine plasma and IgG-specific N-glycosylation in AIH and compare it with healthy controls and other liver diseases. Methods: In this cross-sectional cohort study, total plasma N-glycosylation and IgG Fc glycosylation analysis was performed by mass spectrometry for 66 AIH patients, 60 age- and sex-matched healthy controls, 31 primary biliary cholangitis patients, 10 primary sclerosing cholangitis patients, 30 non-alcoholic fatty liver disease patients and 74 patients with viral or alcoholic hepatitis. A total of 121 glycans were quantified per individual. Associations between glycosylation traits and AIH were investigated as compared to healthy controls and other liver diseases. Results: Glycan traits bisection (OR: 3.78 [1.88–9.35], p-value: 5.88 × 10− 3), tetraantennary sialylation per galactose (A4GS) (OR: 2.88 [1.75–5.16], p-value: 1.63 × 10− 3), IgG1 galactosylation (OR: 0.35 [0.2–0.58], p-value: 3.47 × 10− 5) and hybrid type glycans (OR: 2.73 [1.67–4.89], p-value: 2.31 × 10− 3) were found as discriminators between AIH and healthy controls. High A4GS differentiated AIH from other liver diseases, while bisection associated with cirrhosis severity. Conclusions: Compared to other liver diseases, AIH shows distinctively high A4GS levels in plasma, with potential implications on glycoprotein function and clearance. Plasma-derived glycosylation has potential to be used as a diagnostic marker for AIH in the future. This may alleviate the need for a liver biopsy at diagnosis. Glycosidic changes should be investigated further in longitudinal studies and may be used for diagnostic and monitoring purposes in the future. [ABSTRACT FROM AUTHOR]

Background & aimsThe stimulator of interferon genes (STING)/TANK-binding kinase 1 (TBK1) pathway is vital in mediating innate immune and inflammatory responses during oxidative/endoplasmic reticulum (ER) stress. However, it remains unknown whether macrophage thioredoxin-interacting protein (TXNIP) may regulate TBK1 function and cell death pathways during oxidative/ER stress.MethodsA mouse model of hepatic ischaemia/reperfusion injury (IRI), the primary hepatocytes, and bone marrow-derived macrophages were used in the myeloid-specific TXNIP knockout (TXNIPM-KO) and TXNIP-proficient (TXNIPFL/FL) mice.ResultsThe TXNIPM-KO mice were resistant to ischaemia/reperfusion (IR) stress-induced liver damage with reduced serum alanine aminotransferase (ALT)/aspartate aminotransferase (AST) levels, macrophage/neutrophil infiltration, and pro-inflammatory mediators compared with the TXNIPFL/FL controls. IR stress increased TXNIP, p-STING, and p-TBK1 expression in ischaemic livers. However, TXNIPM-KO inhibited STING, TBK1, interferon regulatory factor 3 (IRF3), and NF-κB activation with interferon-β (IFN-β) expression. Interestingly, TXNIPM-KO augmented nuclear factor (erythroid-derived 2)-like 2 (NRF2) activity, increased antioxidant gene expression, and reduced macrophage reactive oxygen species (ROS) production and hepatic apoptosis/necroptosis in IR-stressed livers. Mechanistically, macrophage TXNIP deficiency promoted cylindromatosis (CYLD), which colocalised and interacted with NADPH oxidase 4 (NOX4) to enhance NRF2 activity by deubiquitinating NOX4. Disruption of macrophage NRF2 or its target gene 2',5' oligoadenylate synthetase-like 1 (OASL1) enhanced Ras GTPase-activating protein-binding protein 1 (G3BP1) and TBK1-mediated inflammatory response. Notably, macrophage OASL1 deficiency induced hepatocyte apoptotic peptidase activating factor 1 (APAF1), cytochrome c, and caspase-9 activation, leading to increased caspase-3-initiated apoptosis and receptor-interacting serine/threonine-protein kinase 3 (RIPK3)-mediated necroptosis.ConclusionsMacrophage TXNIP deficiency enhances CYLD activity and activates the NRF2-OASL1 signalling, controlling IR stress-induced liver injury. The target gene OASL1 regulated by NRF2 is crucial for modulating STING-mediated TBK1 activation and Apaf1/cytochrome c/caspase-9-triggered apoptotic/necroptotic cell death pathway. Our findings underscore a novel role of macrophage TXNIP-mediated CYLD-NRF2-OASL1 axis in stress-induced liver inflammation and cell death, implying the potential therapeutic targets in liver inflammatory diseases.Lay summaryLiver inflammation and injury induced by ischaemia and reperfusion (the absence of blood flow to the liver tissue followed by the resupply of blood) is a significant cause of hepatic dysfunction and failure following liver transplantation, resection, and haemorrhagic shock. Herein, we uncover an underlying mechanism that contributes to liver inflammation and cell death in this setting and could be a therapeutic target in stress-induced liver inflammatory injury.

This study aimed to evaluate the protective role and potential mechanisms of Xie Zhuo Tiao Zhi decoction (XZTZ) on alcohol-associated liver disease (ALD). XZTZ significantly alleviated alcohol-induced liver dysfunction, based on histological examinations and biochemical parameters after 4-week administration. Mechanically, alcohol-stimulated hepatic oxidative stress was ameliorated by XZTZ, accompanied by the improvement of Nrf2/Keap1 expression and alcoholactivated phosphorylation of pro-inflammatory transcription factors, including JNK, P38, P65, and IαB&, were rescued by XZTZ. In conclusion, XZTZ demonstrates potential in alleviating alcohol-induced liver injury, oxidative stress, and inflammation possibly through modulation of Nrf2/Keap1 and MAPKs/NF-κB signaling pathways, suggesting its potential as a therapeutic option for patients with alcoholic liver disease. [ABSTRACT FROM AUTHOR]

Introduction: The alarmin IL-33 has been implicated in the pathology of immune-mediated liver diseases. IL-33 activates regulatory T cells (Tregs) and type 2 innate lymphoid cells (ILC2s) expressing the IL-33 receptor ST2. We have previously shown that endogenous IL-33/ST2 signaling activates ILC2s that aggravate liver injury in murine immune-mediated hepatitis. However, treatment of mice with exogenous IL-33 before induction of hepatitis ameliorated disease severity. Since IL-33 induces expression of amphiregulin (AREG) crucial for Treg function, we investigated the immunoregulatory role of the ST2+ Treg/AREG axis in immune-mediated hepatitis. Methods: C57BL/6, ST2-deficient (Il1rl1-/-) and Areg-/- mice received concanavalin A to induce immune-mediated hepatitis. Foxp3Cre+ x ST2fl/fl mice were pre-treated with IL-33 before induction of immune-mediated hepatitis. Treg function was assessed by adoptive transfer experiments and suppression assays. The effects of AREG and IL-33 on ST2+ Tregs and ILC2s were investigated in vitro. Immune cell phenotype was analyzed by flow cytometry. Results and discussion: We identified IL-33-responsive ST2+ Tregs as an effector Treg subset in the murine liver, which was highly activated in immune-mediated hepatitis. Lack of endogenous IL-33 signaling in Il1rl1-/- mice aggravated disease pathology. This was associated with reduced Treg activation. Adoptive transfer of exogenous IL-33-activated ST2+ Tregs before induction of hepatitis suppressed inflammatory T-cell responses and ameliorated disease pathology. We further showed increased expression of AREG by hepatic ST2+ Tregs and ILC2s in immune-mediated hepatitis. Areg-/- mice developed more severe liver injury, which was associated with enhanced ILC2 activation and less ST2+ Tregs in the inflamed liver. Exogenous AREG suppressed ILC2 cytokine expression and enhanced ST2+ Treg activation in vitro. In addition, Tregs from Areg-/- mice were impaired in their capacity to suppress CD4+ T-cell activation in vitro. Moreover, application of exogenous IL-33 before disease induction did not protect Foxp3Cre+ x ST2fl/fl mice lacking ST2+ Tregs from immune-mediated hepatitis. In summary, we describe an immunoregulatory role of the ST2+ Treg/AREG axis in immune-mediated hepatitis, in which AREG suppresses the activation of hepatic ILC2s while maintaining ST2+ Tregs and reinforcing their immunosuppressive capacity in liver inflammation. [ABSTRACT FROM AUTHOR]

Non-alcoholic fatty liver disease (NAFLD) is a prevalent chronic liver condition observed globally, with the potential to progress to non-alcoholic steatohepatitis (NASH), cirrhosis, and even hepatocellular carcinoma. Currently, the US Food and Drug Administration (FDA) has not approved any drugs for the treatment of NAFLD. NAFLD is characterized by histopathological abnormalities in the liver, such as lipid accumulation, steatosis, hepatic balloon degeneration, and inflammation. Dysbiosis of the gut microbiota and its metabolites significantly contribute to the initiation and advancement of NAFLD. Bacteroides, a potential probiotic, has shown strong potential in preventing the onset and progression of NAFLD. However, the precise mechanism by which Bacteroides treats NAFLD remains uncertain. In this review, we explore the current understanding of the role of Bacteroides and its metabolites in the treatment of NAFLD, focusing on their ability to reduce liver inflammation, mitigate hepatic steatosis, and enhance intestinal barrier function. Additionally, we summarize how Bacteroides alleviates pathological changes by restoring the metabolism, improving insulin resistance, regulating cytokines, and promoting tight-junctions. A deeper comprehension of the mechanisms through which Bacteroides is involved in the pathogenesis of NAFLD should aid the development of innovative drugs targeting NAFLD. [ABSTRACT FROM AUTHOR]

Metabolic dysfunction-associated steatotic liver disease (MASLD) has emerged as the most common liver disease worldwide in recent years. MASLD commonly presents as simple hepatic steatosis, but ~25% of patients develop liver inflammation, progressive fibrosis, liver cirrhosis and related hepatocellular carcinoma. Liver inflammation and the degree of fibrosis are key determinants of the prognosis. The pathophysiology of liver inflammation is incompletely understood and involves diverse factors and specifically innate and adaptive immune responses. More specifically, diverse mediators of innate immunity such as proinflammatory cytokines, adipokines, inflammasomes and various cell types like mononuclear cells, macrophages and natural killer cells are involved in directing the inflammatory process in MASLD. The activation of innate immunity is driven by various factors including excess lipids and lipotoxicity, insulin resistance and molecular patterns derived from gut commensals. Targeting pathways of innate immunity might therefore appear as an attractive therapeutic strategy in the future management of MASLD and possibly its complications. [ABSTRACT FROM AUTHOR]

The aim of this study is to review and analyze the pleiotropic effects of TGF-β in physiological and pathological conditions of the liver, with particular emphasis on its role in immune suppression, wound healing, regulation of cell growth and differentiation, and liver cell apoptosis. A literature review was conducted, including 52 studies, comprising review articles, in vitro and in vivo studies, and meta-analyses. Only studies published in peer-reviewed scientific journals were included in the analysis. TGF-β is a pleiotropic growth factor that is crucial for the liver, both in physiology and pathophysiology. Although its functions are complex and diverse, TGF-β plays a constant role in immune suppression, wound healing, and the regulation of cell growth and differentiation. In concentrations exceeding the norm, it can induce the apoptosis of liver cells. Increased TGF-β levels are observed in many liver diseases, such as fibrosis, inflammation, and steatosis. TGF-β has been shown to play a key role in many physiological and pathological processes of the liver, and its concentration may be a potential diagnostic and prognostic marker in liver diseases. [ABSTRACT FROM AUTHOR]

Dietary soy protein and soy isoflavones have anti-inflammatory properties. Previously, we reported that feeding soy protein concentrate diet (SPC) with low or high isoflavone (LIF or HIF) to young (seven-week-old) obese (fa/fa) Zucker rats inhibits lipopolysaccharide (LPS) translocation and decreases liver inflammation compared to a casein control (CAS) diet. The current study investigated whether SPC-LIF and SPC-HIF diets would reduce liver inflammation in adult obese Zucker rats fed a CAS diet. A total of 21 six-week-old male obese (fa/fa) Zucker rats were given CAS diet for 8 weeks to develop obesity then randomly assigned to CAS, SPC-LIF, or SPC-HIF (seven rats/group) diet for an additional 10 weeks. The expression of LPS-translocation, inflammation, and intestinal permeability markers were quantified by qPCR in liver, visceral adipose tissue (VAT), and colon. LPS concentration was determined in both the colon content and fecal samples by a Limulus amebocyte lysate (LAL) test. SPC-LIF and SPC-HIF diets significantly decreased liver LPS-binding protein (LBP) expression compared to CAS diet (p < 0.01 and p < 0.05, respectively). SPC-HIF diet also significantly decreased liver MCP-1 and TNF-α expression (p < 0.05) and had a trend to decrease liver iNOS expression (p = 0.06). In the colon, SPC-HIF diet significantly increased LBP expression compared to CAS diet (p < 0.05). When samples from all three groups were combined, there was a negative correlation between colon LBP expression and liver LBP expression (p = 0.046). SPC diets did not alter the expression of intestinal permeability markers (i.e., occludin, claudin 3, and zonula occludens-1) in the colon or inflammation markers (i.e., TNF-α and iNOS) in VAT or the colon. LPS levels in the colon content did not differ between any groups. Fecal LPS levels were significantly higher in the SPC-LIF and SPC-HIF groups compared to the CAS group (p < 0.01). In conclusion, SPC, particularly SPC with HIF, reduces liver LBP expression and inflammation makers (i.e., TNF-α and MCP-1 expression) in adult obese Zucker rats, likely by reducing LPS translocation. [ABSTRACT FROM AUTHOR]

Inflammatory bowel conditions can involve nearly all organ systems and induce pathological processes through increased oxidative stress, lipid peroxidation and disruption of the immune response. Patients with inflammatory bowel disease (IBD) are at high risk of having extra-intestinal manifestations, for example, in the hepatobiliary system. In 30% of patients with IBD, the blood values of liver enzymes, such as AST and ALT, are increased. Moreover, treatments for inflammatory bowel diseases may cause liver toxicity. Apple polyphenol extracts are widely acknowledged for their potential antioxidant effects, which help prevent damage from oxidative stress, reduce inflammation, provide protection to the liver, and enhance lipid metabolism. The aim of this study was to investigate whether the polyphenol apple extract from Malus domestica cv. 'Limoncella' (LAPE) may be an effective intervention for the treatment of IBD-induced hepatotoxicity. The LAPE was administrated in vivo by oral gavage (3–300 mg/kg) once a day for 3 consecutive days, starting 24 h after the induction of dinitro-benzenesulfonic acid (DNBS) colitis in mice. The results showed that LAPE significantly attenuated histological bowel injury, myeloperoxidase activity, tumor necrosis factor and interleukin (IL-1β) expressions. Furthermore, LAPE significantly improved the serum lipid peroxidation and liver injury in DNBS-induced colitis, as well as reduced the nuclear transcription factor-kappaB activation. In conclusion, these results suggest that LAPE, through its antioxidant and anti-inflammatory properties, could prevent liver damage induced by inflammatory bowel disease. [ABSTRACT FROM AUTHOR]

Liver damage caused by various factors results in fibrosis and inflammation, leading to cirrhosis and cancer. Fibrosis results in the accumulation of extracellular matrix components. The role of STAT proteins in mediating liver inflammation and fibrosis has been well documented; however, approved therapies targeting STAT3 inhibition against liver disease are lacking. This study investigated the anti-fibrotic and anti-inflammatory effects of STAT3 decoy oligodeoxynucleotides (ODN) in hepatocytes and liver fibrosis mouse models. STAT3 decoy ODN were delivered into cells using liposomes and hydrodynamic tail vein injection into 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-fed mice in which liver injury was induced. STAT3 target gene expression changes were verified using qPCR and Western blotting. Liver tissue fibrosis and bile duct proliferation were assessed in animal experiments using staining techniques, and macrophage and inflammatory cytokine distribution was verified using immunohistochemistry. STAT3 decoy ODN reduced fibrosis and inflammatory factors in liver cancer cell lines and DDC-induced liver injury mouse model. These results suggest that STAT3 decoy ODN may effectively treat liver fibrosis and must be clinically investigated. [ABSTRACT FROM AUTHOR]

Simple Summary: Our previous study suggested that glutamine (Gln), defined as a conditionally essential amino acid, contributed to improving growth performance, alleviating inflammatory responses and intestinal permeability, as well as rescuing the destroyed intestinal mucosa induced by LPS exposure. In addition, it was demonstrated that LPS-induced immune stress led to a severe loss of muscle mass. Here, Gln was proven to function in regulating inflammatory responses, protein synthesis, and degradation during sepsis. Our results showed that Gln administration attenuated liver inflammatory reactions, elevated protein synthesis, and inhibited protein degradation of broilers subjected to LPS challenge. The aim of our present study was to investigate the effects of Gln supplementation on liver inflammatory responses as well as protein synthesis and degradation in the muscle of LPS-challenged broilers. A total of 120 one-day-old male broiler chickens (Arbor Acres Plus) were randomly arranged in a 2 × 2 factorial design with five replicates per treatment and six broilers per replicate, containing two main factors: immune challenge (injected with LPS in a dose of 0 or 500 µg/kg of body weight) and dietary treatments (supplemented with 1.22% alanine or 1% Gln). After feeding with an alanine or Gln diet for 15 days, broilers were administrated an LPS or a saline injection at 16 and 21 days. The results showed that Gln supplementation alleviated the increased mRNA expressions of interleukin-6, interleukin-1β, and tumor necrosis factor-α induced by LPS in liver. Moreover, the increased activity of aspartate aminotransferase combined with the decreased expression of glutaminase in muscle were observed following Gln addition. In addition, in comparison with the saline treatment, LPS challenge altered the signaling molecules' mRNA expressions associated with protein synthesis and degradation. However, Gln supplementation reversed the negative effects on protein synthesis and degradation in muscle of LPS-challenged broilers. Taken together, Gln supplementation had beneficial effects: alleviating inflammatory responses, promoting protein synthesis, and inhibiting protein degradation of LPS-challenged broilers. [ABSTRACT FROM AUTHOR]

Liver disease-related mortality is a major cause of death worldwide. Hepatic innate and adaptive immune cells play diverse roles in liver homeostasis and disease. Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells. MDSCs can be broadly divided into monocytic MDSCs and polymorphonuclear or granulocytic MDSCs, and they functionally interact with both liver parenchymal and nonparenchymal cells, such as hepatocytes and regulatory T cells, to impact liver disease progression. The infiltration and activation of MDSCs in liver disease can be regulated by inflammatory chemokines and cytokines, tumor-associated fibroblasts, epigenetic regulation factors, and gut microbiota during liver injury and cancer. Given the pivotal roles of MDSCs in advanced liver diseases, they can be targeted to treat primary and metastatic liver cancer, liver generation, alcoholic and nonalcoholic liver disease, and autoimmune hepatitis. Currently, several treatments such as the antioxidant and anti-inflammatory agent berberine are under preclinical and clinical investigation to evaluate their therapeutic efficacy on liver disease and their effect on MDSC infiltration and function. Phenotypic alteration of MDSCs in different liver diseases that are in a model-dependent manner and lack special markers for distinct MDSCs are challenges for targeting MDSCs to treat liver disease. Multi-omics study is an option to uncover the features of disease-specific MDSCs and potential gene or protein targets for liver disease treatment. In summary, MDSCs play important roles in the pathogenesis and progression of liver disease by regulating both intrahepatic innate and adaptive immune responses. [ABSTRACT FROM AUTHOR]

Background: Dihydroartemisinin (DHA), a derivative of Artemisia annua, has been shown to possess anti-inflammatory properties. Besides, Yes-associated protein 1 (YAP1) plays a crucial role in maintaining liver homeostasis. Methods: This study used Yap1Flox/Flox, Albumin-Cre mice with hepatocyte-specific Yap1 knockout (referred to as Yap1LKO) and their control mice (Yap1Flox/Flox, referred to as Yap1Flox). The effect of Yap1 on lipid metabolism homeostasis was investigated through non-targeted metabolomic analysis of mouse liver. Subsequently, DHA was administered to Yap1LKO mice to assess its potential as a treatment. Liver pathology was evaluated via H&E staining, and the levels of AST, ALT, and TG were quantified using biochemical assays. The contents of arachidonic acid (AA), prostaglandin E1 (PGE1), and leukotrienes (LT) in the liver were measured using ELISA, while the protein expressions of PLIN2, 5-lipoxygenase (5-LOX), and cyclooxygenase-2 (COX-2) were analyzed through IHC staining. Results: Hepatocyte-specific Yap1 knockout activated the AA metabolic pathway, resulting in increased elevated levels of AA, PGE1, and LT levels, along with inflammatory cytokine infiltration. DHA mitigated the elevation of metabolites such as PGE1 and LT caused by the AA metabolic pathway activation by down-regulating the levels of COX-2 and 5-LOX in the liver of Yap1LKO mice. Moreover, it alleviated the accumulation of lipid vacuoles and reduced triglyceride (TG) and perilipin-2 (PLIN2) levels in the liver of Yap1LKO mice. Conclusions: Excessively low YAP1 expression induces liver inflammation and disturbances in lipid metabolism, whereas DHA modulated AA metabolism and mitigated liver inflammation by inhibiting the activation of 5-LOX and COX-2.

Copper (Cu) serves as an essential cofactor in all organisms, yet excessive Cu exposure is widely recognized for its role in inducing liver inflammation. However, the precise mechanism by which Cu triggers liver inflammation in ducks, particularly in relation to the interplay in gut microbiota regulation, has remained elusive. In this investigation, we sought to elucidate the impact of Cu exposure on liver inflammation through gut-liver axis in ducks. Our findings revealed that Cu exposure markedly elevated liver AST and ALT levels and induced liver inflammation through upregulating pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) and triggering the LPS/TLR4/NF-κB signaling pathway. Simultaneously, Cu exposure induced alterations in the composition of intestinal flora communities, notably increasing the relative abundance of Sphingobacterium, Campylobacter, Acinetobacter and reducing the relative abundance of Lactobacillus. Cu exposure significantly decreased the protein expression related to intestinal barrier (Occludin, Claudin-1 and ZO-1) and promoted the secretion of intestinal pro-inflammatory cytokines. Furthermore, correlation analysis was observed that intestinal microbiome and gut barrier induced by Cu were closely related to liver inflammation. Fecal microbiota transplantation (FMT) experiments further demonstrated the microbiota-depleted ducks transplanting fecal samples from Cu-exposed ducks disturbed the intestinal dysfunction, which lead to impaire liver function and activate the liver inflammation. Our study provided insights into the mechanism by which Cu exposure induced liver inflammation in ducks through the regulation of gut-liver axis. These results enhanced our comprehension of the potential mechanisms driving Cu-induced hepatotoxicity in avian species.

This work aims to study the effects of oral gavage (0.2 mg/g body weight) of elaidic acid (C18:1–9 t, EA) and linoelaidic acid (C18:2–9 t,12 t, LEA) on lipid metabolism, inflammation and gut homeostasis of mice. Results showed that both EA and LEA gavage significantly increased LDL-c, TC and oxidative stress levels in the liver and serum and may stimulate liver inflammation via NF-κB and MAPK signaling pathway. Compared with EA, LEA gavage significantly promoted TAG accumulation and inflammatory signaling. Serum lipidomics revealed that LEA intake significantly increased the concentration of ∼50 TAGs, while EA gavage primarily caused significant decreases in several SMs. 16S rRNA demonstrated that LEA ingestion markedly changed fecal microbiota by enriching Lactobacillus (phylum Firmicutes), however, EA treatment did not affect it. Overall, LEA gavage has more severe consequences on TAG accumulation, inflammation and microbial structure than EA, highlighting that the number of trans double bonds affects these processes.

Background and aims: Normal serum transaminases and immunoglobulin G (IgG) levels are surrogate markers for hepatic histologic disease activity in autoimmune hepatitis (AIH). This study aimed to evaluate liver inflammation in patients with AIH with normal serum alanine aminotransferase (ALT) and IgG levels. Methods: Two hundred and five AIH patients who underwent liver biopsy in four medical centers were included. Logistic regression analysis was used to identify risk factors associated with advanced inflammation. Results: One hundred and thirty-one (63.9 %) AIH patients had advanced liver inflammation, and 108 (52.7 %) patients had advanced liver fibrosis. 60.0 % of patients with normal ALT and 51.7 % of patients with normal ALT and IgG had advanced inflammation. However, 76.7 % and 35.0 % of patients with or without advanced fibrosis with normal ALT had advanced inflammation, while the corresponding proportions of advanced inflammation were 78.6 % and 26.7 % in patients with normal ALT and IgG, respectively. Moreover, 81.0 % and 44.8 % of patients with and without cirrhosis with normal ALT had advanced inflammation, while the corresponding proportions were 83.3 % and 29.4 % in patients with normal ALT and IgG, respectively. Red cell distribution width (OR = 1.325, 95%CI 1.045–1.681, P = 0.020) and PT (OR = 1.514, 95%CI 1.138–2.014, P = 0.004) were independent factors associated with advanced inflammation. Conclusions: High proportion of advanced inflammation was found in AIH patients with normal ALT and IgG levels despite without advanced fibrosis. Although using non-invasive methods may contribute to rule out liver fibrosis in AIH patients with normal ALT and IgG levels, liver biopsy is encouraged to assess liver inflammation.

Non-alcoholic fatty liver disease (NAFLD) is increasingly prevalent, but treatment options are limited. Previous studies have demonstrated the hepatoprotective effects of Polysaccharide of Atractylodes macrocephala Koidz (PAMK) against liver injury induced by various causes, but its potential in alleviating NAFLD remains unknown. This study aimed to investigate the potential of PAMK in improving NAFLD and its regulatory effects on gene transcription during the process. The results indicated that Highfatdiet (HFD) could induce NAFLD in mice, and PAMK was found to alleviate symptoms of NAFLD and mitigate liver injury caused by HFD. Transcriptome analysis revealed that PAMK affects both metabolic and inflammatory pathways, suggesting its dual impact on maintaining metabolic homeostasis and suppressing inflammation during NAFLD progression. The results of liver biochemical markers, key genes of the cholesterol pathway, glucose (GLU), and inflammatory factors further demonstrated the dual role of PAMK in metabolism and inflammation.

AimLow-grade inflammation is the hallmark of non-alcoholic fatty liver diseases (NAFLD) and non-alcoholic steatohepatitis (NASH). The leakage of microbiota-derived products can contribute to liver inflammation during NAFLD/NASH development. Here, we assessed the roles of gut microbial DNA-containing extracellular vesicles (mEVs) in regulating liver cellular abnormalities in the course of NAFLD/NASH.MethodsWe performed studies with Vsig4-/- , C3-/- , cGAS-/- , and their wild-type littermate mice. Vsig4+ macrophage population and bacterial DNA abundance were examined in both mouse and human liver by either flow cytometric or immunohistochemistry analysis. Gut mEVs were adoptively transferred into Vsig4-/- , C3-/- , cGAS-/- , or littermate WT mice, and hepatocyte inflammation and HSC fibrogenic activation were measured in these mice.ResultsNon-alcoholic fatty liver diseases and non-alcoholic steatohepatitis development was concomitant with a diminished liver Vsig4+ macrophage population and a marked bacterial DNA enrichment in both hepatocytes and HSCs. In the absence of Vsig4+ macrophages, gut mEVs translocation led to microbial DNA accumulation in hepatocytes and HSCs, resulting elevated hepatocyte inflammation and HSC fibrogenic activation. In contrast, in lean WT mice, Vsig4+ macrophages remove gut mEVs from bloodstream through a C3-dependent opsonization mechanism and prevent the infiltration of gut mEVs into hepatic cells. Additionally, Vsig4-/- mice more quickly developed significant liver steatosis and fibrosis than WT mice after Western diet feeding. In vitro treatment with NASH mEVs triggered hepatocyte inflammation and HSC fibrogenic activation. Microbial DNAs are key cargo for the effects of gut mEVs by activating cGAS/STING.ConclusionAccumulation of microbial DNAs fuels the development of NAFLD/NASH-associated liver abnormalities.

Background & Aims: Acetaminophen (APAP) overdose is the most common cause of drug-induced liver injury worldwide. Uric acid (UA) is involved in sterile inflammation in many organs, but its role in APAP-induced liver injury remains elusive. Methods: We quantified the concentration of UA in the serum and liver tissues of APAP-overdosed mice and explored the changes in proteins involved in UA synthesis, absorption, and degeneration on APAP stimulation. We also examined the effects of inhibiting hepatocyte UA synthesis or reabsorption on APAP-induced liver injury in mice. Furthermore, we explored the process of UA clearance by peripheral macrophages. Results: APAP overdose significantly increased intrahepatic UA contents, which occurred earlier than apparent hepatocyte injury in APAP-overdosed mice. APAP overdose induced significant DNA leakage and may thereby increase the substrate of UA synthesis. APAP overdose also significantly increased the enzymatic activity of xanthine oxidase and urate oxidase and decreased the expression of the UA reabsorption transporter GLUT9 in hepatocytes. Inhibiting hepatocyte UA synthesis by febuxostat or reabsorption by hepatic-specific knockout of GLUT9 alleviated APAP-induced liver injury. Further experiments showed that monosodium urate but not soluble UA may be a major form of UA mediating hepatocyte injury. Additionally, monosodium urate further recruited circulating macrophages into the liver and then aggravated inflammation by increasing the levels of inflammatory factors and reactive oxygen species. Deletion of macrophages significantly ameliorated APAP-induced liver injury in mice. Conclusions: APAP overdose induces excessive UA production and leads to local high concentrations in the liver, which further injures cells and induces liver inflammation. Inhibiting the production of UA may be a potential therapeutic option for treating APAP-induced liver injury.

Background and Aims: The large global population of patients with metabolic dysfunction-associated steatotic liver disease (MASLD) has recently been shown to have an association with chronic kidney disease (CKD) due to a host of proposed mechanisms, one of which being lipoprotein dysmetabolism. Furthermore, metabolic comorbidities have been concurrently prevalent in MASLD and CKD independently. This study aimed at analyzing risk and predictive traits among an obese population for both MASLD and CKD. Methods: A retrospective chart review of 546 obese patients with a diagnosis of either MASLD or metabolic dysfunction-associated steatohepatitis between January 2020 and June 2021 was performed. Markers of liver and kidney function in addition to demographic data and renoprotective medications were recorded. Both univariable and multivariable linear regression analyses were performed to understand possible associations between MASLD markers, renal function, and markers of metabolic derangements. Results: Univariate analysis revealed that increased age (P < .001), elevated alanine aminotransferase (defined as alanine aminotransferase ≥ 30 IU/L, P = .01), low albumin (P = .011), and increasing fibrosis-4 (FIB-4) (P = .005) were statistically associated with a reduced renal function. A reduction in glomerular filtration was associated with an increase in FIB-4 (effect size [beta] of a one-unit increase in glomerular filtration on FIB-4 = −0.013, P < .001) in univariate linear regression. In multivariate linear regression, type 2 diabetes (T2D) was independently associated with increased liver fibrosis (effect size of T2D on FIB-4 = 0.387925, P < .02). Conclusion: Our study shows that in a patient population with obesity and a diagnosis of MASLD, advanced fibrosis is independently associated with reduced renal function.

Background and Aims: Recent studies showed that patients suffering from lysosomal acid lipase deficiency (LAL-D) benefit from enzyme replacement therapy; however, liver histopathology improved in some but not all patients. We hypothesized that the pan-peroxisome proliferator-activated receptor agonist lanifibranor may have beneficial effects on liver inflammation in LAL knockout (Lal−/−) mice based on its promising results in alleviating liver inflammation in patients with metabolic dysfunction-associated steatohepatitis. Methods: Female Lal−/− mice were daily gavaged with lanifibranor or vehicle for 21 days. The effects of the treatment were assessed by measuring body and organ weights, plasma lipids and lipoproteins, as well as hematological parameters, followed by liver proteomics and metabolomics. Results: Lanifibranor treatment slightly altered organ weights without affecting the total body weight of Lal−/− mice. We observed major changes in the proteome, with multiple proteins related to lipid metabolism, peroxisomal, and mitochondrial activities being upregulated and inflammation-related proteins being downregulated in the livers of treated mice. Hepatic lipid levels and histology remained unaltered, whereas plasma triacylglycerol and total cholesterol levels were decreased and the lipoprotein profile of lanifibranor-treated Lal−/− mice improved. Conclusion: Lanifibranor treatment positively affected liver inflammation and dyslipidemia in Lal−/− mice. These findings suggest the necessity of a further combined study of lanifibranor with enzyme replacement therapy in Lal−/− mice to improve the phenotype. Moreover, there is a compelling rationale for conducting clinical trials to assess the efficacy of lanifibranor as a potential treatment option for LAL-D in humans.

Background & aimsAlthough Ikaros (IKZF1) is a well-established transcriptional regulator in leukocyte lymphopoiesis and differentiation, its role in myeloid innate immune responses remains unclear. Sirtuin 1 (SIRT1) is a histone/protein deacetylase involved in cellular senescence, inflammation, and stress resistance. Whether SIRT1 signaling is essential in myeloid cell activation remains uncertain, while the molecular communication between Ikaros and SIRT1, two major transcriptional regulators, has not been studied.MethodsWe undertook molecular and functional studies to interrogate the significance of the myeloid Ikaros-SIRT1 axis in innate immune activation and whether it may serve as a homeostatic sentinel in human liver transplant recipients (hepatic biopsies) and murine models of sterile hepatic inflammation (liver warm ischemia-reperfusion injury in wild-type, myeloid-specific Sirt1-knockout, and CD11b-DTR mice) as well as primary bone marrow-derived macrophage (BMM) cultures (Ikaros silencing vs. overexpression).ResultsIn our clinical study, we identified increased post-reperfusion hepatic Ikaros levels, accompanied by augmented inflammasome signaling yet depressed SIRT1, as a mechanism of hepatocellular damage in liver transplant recipients. In our experimental studies, we identified infiltrating macrophages as the major source of Ikaros in IR-stressed mouse livers. Then, we demonstrated that Ikaros-regulated pyroptosis - induced by canonical inflammasome signaling in BMM cultures - was SIRT1 dependent. Consistent with the latter, myeloid-specific Ikaros signaling augmented hepatic pyroptosis to aggravate pro-inflammatory responses in vivo by negatively regulating SIRT1 in an AMPK-dependent manner. Finally, myeloid-specific SIRT1 was required to suppress pyroptosis, pro-inflammatory phenotype, and ultimately mitigate hepatocellular injury in ischemia-stressed murine livers.ConclusionThese findings identify the Ikaros-SIRT1 axis as a novel mechanistic biomarker of pyroptosis and a putative checkpoint regulator of homeostasis in response to acute hepatic stress/injury in mouse and human livers.Lay summaryThis report describes how crosstalk between Ikaros and SIRT1, two major transcriptional regulators, influence acute hepatic inflammation in murine models of liver ischemia-reperfusion injury and liver transplant recipients. We show that the myeloid Ikaros-SIRT1 axis regulates inflammasome-pyroptotic cell death and hepatocellular damage in stressed livers. Thus, the Ikaros-SIRT1 axis may serve as a novel checkpoint regulator that is required for homeostasis in response to acute liver injury in mice and humans.

BackgroundObesity, non-alcoholic fatty liver disease (NAFLD) and its more advanced form non-alcoholic steatohepatitis (NASH) are important causes of morbidity and mortality worldwide. Bile acid dysregulation is a pivotal part in their pathogenesis. The aim of this study was to evaluate the bile acid sequestrant colesevelam in a microbiome-humanized mouse model of diet-induced obesity and steatohepatitis.MethodsGerm-free C57BL/6 mice were associated with stool from patients with NASH and subjected to 20 weeks of Western diet feeding with and without colesevelam.ResultsColesevelam reduced Western diet-induced body and liver weight gain in microbiome-humanized mice compared with controls. It ameliorated Western diet-induced hepatic inflammation, steatosis, fibrosis and insulin resistance. Colesevelam increased de novo bile acid synthesis and decreased hepatic cholesterol content in microbiome-humanized mice fed a Western diet. It further induced the gene expression of the antimicrobials Reg3g and Reg3b in the distal small intestine and decreased plasma levels of LPS.ConclusionsColesevelam ameliorates Western diet-induced steatohepatitis and obesity in microbiome-humanized mice.

Background & aimsNonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease worldwide. The NLRP3 inflammasome, a platform for caspase-1 activation and release of interleukin 1β, is increasingly recognized in the induction of inflammation and liver fibrosis during NAFLD. However, the cell-specific contribution of NLRP3 inflammasome activation in NAFLD remains unknown.MethodsTo investigate the role of NLRP3 inflammasome activation in hepatocytes, hepatic stellate cells (HSCs) and myeloid cells, a conditional Nlrp3 knock-out mouse was generated and bred to cell-specific Cre mice. Both acute and chronic liver injury models were used: lipopolysaccharide/adenosine-triphosphate to induce in vivo NLRP3 activation, choline-deficient, L-amino acid-defined high-fat diet, and Western-type diet to induce fibrotic nonalcoholic steatohepatitis (NASH). In vitro co-culture studies were performed to dissect the crosstalk between myeloid cells and HSCs.ResultsMyeloid-specific deletion of Nlrp3 blunted the systemic and hepatic increase in interleukin 1β induced by lipopolysaccharide/adenosine-triphosphate injection. In the choline-deficient, L-amino acid-defined high-fat diet model of fibrotic NASH, myeloid-specific Nlrp3 knock-out but not hepatocyte- or HSC-specific knock-out mice showed significant reduction in inflammation independent of steatosis development. Moreover, myeloid-specific Nlrp3 knock-out mice showed ameliorated liver fibrosis and decreased HSC activation. These results were validated in the Western-type diet model. In vitro co-cultured studies with human cell lines demonstrated that HSC can be activated by inflammasome stimulation in monocytes, and this effect was significantly reduced if NLRP3 was downregulated in monocytes.ConclusionsThe study provides new insights in the cell-specific role of NLRP3 in liver inflammation and fibrosis. NLRP3 inflammasome activation in myeloid cells was identified as crucial for the progression of NAFLD to fibrotic NASH. These results may have implications for the development of cell-specific strategies for modulation of NLRP3 activation for treatment of fibrotic NASH.