Mouse Model Of Non-alcoholic Steatohepatitis Research Articles

A new mechanism of thyroid hormone receptor β agonists ameliorating nonalcoholic steatohepatitis by inhibiting intestinal lipid absorption via remodeling bile acid profiles.

Excessive dietary calories lead to systemic metabolic disorders, disturb hepatic lipid metabolism, and aggravate nonalcoholic steatohepatitis (NASH). Bile acids (BAs) play key roles in regulating nutrition absorption and systemic energy homeostasis. Resmetirom is a selective thyroid hormone receptor β (THRβ) agonist and the first approved drug for NASH treatment. It is well known that the THRβ activation could promote intrahepatic lipid catabolism and improve mitochondrial function, however, its effects on intestinal lipid absorption and BA compositions remain unknown. In the present study, the choline-deficient, L-amino acid defined, high-fat diet (CDAHFD) and high-fat diet plus CCl4 (HFD+CCl4)-induced NASH mice were used to evaluate the effects of resmetirom on lipid and BA composition. We showed that resmetirom administration (10 mg·kg-1·d-1, i.g.) significantly altered hepatic lipid composition, especially reduced the C18:2 fatty acyl chain-containing triglyceride (TG) and phosphatidylcholine (PC) in the two NASH mouse models, suggesting that THRβ activation inhibited intestinal lipid absorption since C18:2 fatty acid could be obtained only from diet. Targeted analysis of BAs showed that resmetirom treatment markedly reduced the hepatic and intestinal 12-OH to non-12-OH BAs ratio by suppressing cytochrome P450 8B1 (CYP8B1) expression in both NASH mouse models. The direct inhibition by resmetirom on intestinal lipid absorption was further verified by the BODIPY gavage and the oral fat tolerance test. In addition, disturbance of the altered BA profiles by exogenous cholic acid (CA) supplementation abolished the inhibitory effects of resmetirom on intestinal lipid absorption in both normal and CDAHFD-fed mice, suggesting that resmetirom inhibited intestinal lipid absorption by reducing 12-OH BAs content. In conclusion, we discovered a novel mechanism of THRβ agonists on NASH treatment by inhibiting intestinal lipid absorption through remodeling BAs composition, which highlights the multiple regulation of THRβ activation on lipid metabolism and extends the current knowledge on the action mechanisms of THRβ agonists in NASH treatment.

Fufang Zhenzhu Tiaozhi polysaccharides ameliorates high-fat diet-induced non-alcoholic steatohepatitis and intestinal flora disorders in mice

Non-alcoholic fatty liver disease (NAFLD) is increasingly recognized for its global prevalence and potential progression to more severe liver diseases such as non-alcoholic steatohepatitis (NASH). The primary treatment for NASH is modifying lifestyle through dietary or exercise interventions. The aim of the current study is to investigate the roles of Fufang Zhenzhu Tiaozhi polysaccharides (FTZPs) in mice with NASH. FTZPs were concurrently administered to high-fat diet (HFD)-induced 24-week NASH model mice. FTZPs treatment effectively improved liver lipid metabolism, reduced inflammation and fibrosis, improved the integrity of the intestinal mucosal barrier, and modulated the structure of the intestinal microbiota. FTZPs treatment significantly reduced the abundance of Gammaproteobacteria, Clostridium, and Coprococcus while as induced the abundance of Dehalobacteraceae and Dehalobacterium. Furthermore, sixteen differential metabolites were screened by metabolomics, and the change of asparagine was the most significant. In addition, the correlation analysis showed that there was a significant correlation between asparagine and the aforementioned differential bacteria. The present study demonstrated that FTZPs, as the fundamental pharmacological elements of FTZ (Fufang Zhenzhu Tiaozhi), protect against NASH by improving intestinal barrier damage and regulating intestinal flora with the increase in asparagine.

Serum miR‑29 is increased in mice with early liver fibrosis.

Non-alcoholic steatohepatitis (NASH) is a fatty liver disease that is not caused by alcohol consumption and is characterized by fatty degeneration, inflammation and hepatocellular damage. Therefore, predicting future fibrosis is critical in the early stages of NASH to prevent disease progression. The present study examined histological changes in the liver as well as microRNA (miR/miRNA) expression changes in the liver and serum of NASH mice model to identify potential biomarker candidates that could predict early fibrosis. This study used 6-week-old C57BL/6NJcl male mice and fed the control with a standard solid diet (CE-2) for breeding and propagation and NASH groups with a high-fat diet [choline-deficient high-fat and 0.1% (w/v) methionine supplemented diet], respectively. Agilent Technologies miRNA microarray was used to investigate microRNA expression in the liver and serum. Hematoxylin and eosin staining of the livers of the NASH group mice during the second week of feeding revealed fatty degeneration, balloon-like degeneration and inflammatory cell infiltration, confirming that the mice were in a state of NASH. The livers of the NASH group mice at 6 weeks of feeding showed fibrosis. Microarray analysis revealed that miRNAs were upregulated and 47 miRNAs were downregulated in the liver of the NASH group. Pathway analysis using OmicsNet predicted miR-29 to target collagen genes. Furthermore, miR-29 was downregulated in the livers of NASH-induced mice but upregulated in serum. These findings suggested that lower miR-29 expression in NASH-induced liver would increase collagen expression and fibrosis. Early liver fibrosis suggests that miR-29 leaks from the liver into the bloodstream, and elevated serum miR-29 levels may be a predictive biomarker for early liver fibrosis.

Bofutsushosan (Fangfengtongshengsan) improves early stages of NASH via the gut–liver axis in diabetes-induced NASH model mice

BackgroundThe mechanisms underlying non-alcoholic fatty liver disease (NAFLD) are not fully understood, but the gut microbiota is deeply involved. Because the Japanese traditional medicine bofutsushosan (BTS; Fangfengtongshengsan in Chinese) is known to improve obesity-induced liver injury and increase gut Akkermansia muciniphila, we evaluated its effects in a mouse model of diabetes-induced nonalcoholic steatohepatitis (NASH). MethodsTwo-day-old male C57BL/6J mice were injected subcutaneously with streptozotocin and fed a high-fat diet (HFD) from 4 weeks. Between 5 and 8 weeks, HFD was supplemented with 5% BTS (BTS) or not supplemented (CONT), and plasma, liver, and stool samples were collected and analyzed. ResultsThe NAFLD activity score (NAS), which was consistent with early steatohepatitis in CONT mice, was significantly lower in BTS mice (P = 0.018). Improvement of steatosis contributed most to decreasing NAS. Relative abundances of probiotic Akkermansia muciniphila and Bifidobacterium pseudolongum were significantly higher in BTS mice (both P < 0.05). Positive correlations were observed among NAS, steatosis, ballooning, and body weight change. Liver macrophage markers correlated with some microbes in BTS mice. ConclusionsBTS administration suppressed liver steatosis and improved the gut microbiome, which correlated with some liver factors. BTS may be a promising treatment for NAFLD by maintaining the gut–liver axis.

Utility of pemafibrate in nonalcoholic steatohepatitis model mice induced by a choline-deficient, high-fat diet and dextran sulfate sodium

AimThe purpose of this study was to examine the effect of pemafibrate in a murine model of non-alcoholic steatohepatitis (NASH). MethodsForty-two, 19-week-old, male, C57BL/6J mice were divided into three groups: a Control group (n = 14), a dextran sulfate sodium (DSS) group (n = 14), and a DSS + PEM group (n = 14). All mice were given a standard rodent diet for the first week, followed by a choline-deficient, high-fat diet (CDHF) for the next 12 weeks. The 22nd day after the animals arrived was taken as Day 1 of the experiment. The Control group continued the CDHF diet and MilliQ water. The DSS group continued the CDHF diet, but starting on Day 1, the group received 0.8 % DSS to drink for 7 consecutive days, followed by MilliQ water for 10 days; this was taken as one course, and it was repeated on the same schedule until autopsy. The DSS + PEM group received the CDHF diet with PEM 0.1 mg/kg/day. Their drinking water was the same as that of the DSS group. On Seven animals from each group were autopsied on each of Day 50 and Day 120, and histopathological and immunohistochemical examinations, as well as quantitative RNA and cytokine measurements, of autopsied mice were performed. ResultsPemafibrate improved hepatic steatosis (decreased steatosis area), improved liver inflammation enhanced by DSS (decreased aspartate transaminase and alanine aminotransferase), improved hepatic fibrosis promoted by DSS (decreased fibrotic areas and a marker of fibrosis), inhibited tumorigenesis, and decreased intestinal inflammation in the NASH model mice. ConclusionsIn a murine model of NASH, mixing PEM 0.1 mg/kg/day into the diet inhibited disease progression and tumor formation.

Mechanism of Biejiajian Pills against non-alcoholic steatohepatitis based on lipidomics

This study aims to explore the potential mechanism of Biejiajian Pills in the treatment of non-alcoholic steatohepatitis(NASH) based on lipidomics. A mouse model of NASH was induced by high-fat/high cholesterol diet, and the mice of the normal group were fed with a normal diet. The therapeutic efficacy of Biejiajian Pills against NASH was evaluated through biochemical indexes in both of serum and liver, as well as the hepatic histopathology. Lipid metabolites in the liver were detected by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS)-based lipidomics. Then the partial least-squares discriminant analysis, t-test and receiver operating characteristic curve analysis were performed to screen the differential lipid metabolites and the main biomarkers. The proteins and genes involved in the lipid metabolism and inflammatory response were detected by Western blot and qPCR. The results demonstrated that Biejiajian Pills notably lowered the levels of alanine aminotransferase(ALT), aspartate aminotransferase(AST), and alkaline phosphatase(ALP) in the serum and the levels of triglyceride(TG) and total cholesterol(TC) in the liver tissue. In addition, Biejiajian Pills alleviated the lipid accumulation, hepatocyte ballooning, and liver fibrosis. Lipidomics revealed that Biejiajian Pills regulated the content of 11 biomarkers including phosphatidyl choline(PC), phosphatidyl ethanolamine(PE), sphingomyelin(SM), and ceramide(Cer). The results of Western blot and qPCR demonstrated that Biejiajian Pills regulated the expression of sterol regulatory element-binding protein 1(SREBP1), peroxisome proliferator-activated receptor gamma(PPARγ) and phospho-AMP-activated protein kinase(p-AMPK), and the mRNA level of fatty acid translocase 36 gene(Cd36), Pparγ, cardiolipin synthase 1 gene(Crls1), and phospholipase Cβ2 gene(Plcβ2). Furthermore, Biejiajian Pills displayed inhibitory effects on phospho-p38 MAPK(p-p38 MAPK) and phospho-ERK1/2(p-ERK1/2) and the mRNA levels of interleukin-6 gene(Il-6), interleukin-1β gene(Il-1β) and tumor necrosis factor-α gene(Tnf-α). In conclusion, Biejiajian Pills could alleviate the lipid metabolism disorders and regulate the expression of SREBP1, PPARγ, and p-AMPK and the mRNA levels of pro-inflammatory cytokines.

Increased hepatoprotective effects of the novel farnesoid X receptor agonist INT-787 versus obeticholic acid in a mouse model of nonalcoholic steatohepatitis.

The nuclear farnesoid X receptor (FXR), a master regulator of bile acid and metabolic homeostasis, is a key target for treatment of nonalcoholic steatohepatitis (NASH). This study compared efficacy of FXR agonists obeticholic acid (OCA) and INT-787 by liver histopathology, plasma biomarkers of liver damage, and hepatic gene expression profiles in the Amylin liver NASH (AMLN) diet-induced and biopsy-confirmed Lepob/ob mouse model of NASH. Lepob/ob mice were fed the AMLN diet for 12 weeks before liver biopsy and subsequent treatment with vehicle, OCA, or INT-787 for 8 weeks. Hepatic steatosis, inflammation, and fibrosis (liver lipids, galectin-3, and collagen 1a1 [Col1a1], respectively), as well as plasma alanine transaminase (ALT) and aspartate transaminase (AST) levels, were assessed. Hepatic gene expression was assessed in Lepob/ob mice that were fed the AMLN diet for 14 weeks then treated with vehicle, OCA, or INT-787 for 2 weeks. INT-787, which is equipotent to OCA but more hydrophilic, significantly reduced liver lipids, galectin-3, and Col1a1 compared with vehicle, and to a greater extent than OCA. INT-787 significantly reduced plasma ALT and AST levels, whereas OCA did not. INT-787 modulated a substantially greater number of genes associated with FXR signaling, lipid metabolism, and stellate cell activation relative to OCA in hepatic tissue. These findings demonstrate greater efficacy of INT-787 treatment compared with OCA in improving liver histopathology, decreasing liver enzyme levels, and enhancing gene regulation, suggesting superior clinical potential of INT-787 for the treatment of NASH and other chronic liver diseases.

A high-dose of ursodeoxycholic acid treatment alleviates liver inflammation by remodeling gut microbiota and bile acid profile in a mouse model of non-alcoholic steatohepatitis

Ursodeoxycholic acid (UDCA) is a hydrophilic bile acid commonly used for treating cholestatic liver disease. However, its efficacy on non-alcoholic steatohepatitis (NASH) was controversial. This study aimed to investigate the impact of a high dosage of UDCA on a mouse model of NASH. Forty 6-week-old mice were fed a high-fat high-cholesterol (HFHC) diet for 12 weeks to establish a mouse model of NASH, and then divided into four groups: two groups transitioned to a normal diet, and the other two groups maintained the HFHC diet. Each group was administered a daily dosage of 300 mg/kg of UDCA or saline for a period of 8 weeks. The 16 s ribosomal RNA genes extracted from mice fecal pellets were sequenced using next-generation sequencing techniques. Serum bile acid profiles were quantified using liquid chromatography electrospray ionization tandem mass spectrometry method. The results showed that UDCA treatment ameliorated liver inflammation, without affecting liver fibrosis. UDCA treatment reduced the relative abundance of the genera Bacteroides, Parabacteroides, and Intestinimonas, whereas increased the relative abundance of the genera norank_f_Muribaculaceae and Parasutterella in the HFHC-maintaining groups. The serum levels of total bile acids and total primary bile acids increased, whereas those of endogenous primary bile acids decreased after UDCA treatment. Correlation analysis showed that primary bile acids were negatively correlated with the genera norank_f_Christensenellaceae and unclassified_f_Ruminococcaceae. In conclusion, a high dosage of UDCA can alleviate liver inflammation, probably by modifying the composition of gut microbiota and serum bile acid profiles in NASH mice.

O-GlcNAcylation promotes the progression of nonalcoholic fatty liver disease by upregulating the expression and function of CD36

Background and aimsNonalcoholic fatty liver disease (NAFLD) and its progressive variant, nonalcoholic steatohepatitis (NASH), constitute a burgeoning worldwide epidemic with no FDA-approved pharmacotherapies. The multifunctional immunometabolic receptor, fatty acid translocase CD36 (CD36), plays an important role in the progression of hepatic steatosis. O-GlcNAcylation is a crucial posttranslational modification that mediates the distribution and function of CD36, but its involvement in NAFLD remains poorly understood. MethodsO-GlcNAcylation and CD36 expression were evaluated in human liver tissues obtained from NASH patients and normal control. Mice with hepatocyte-specific CD36 knockout were administered adeno-associated viral vectors expressing wild-type CD36 (WT-CD36) or CD36 O-GlcNAcylation site mutants (S468A&T470A-CD36) and were provided with a high-fat/high-cholesterol (HFHC) diet for 3 months. RT–qPCR analysis, immunoblotting, dual-luciferase reporter assays, chromatin immunoprecipitation, and coimmunoprecipitation were performed to explore the mechanisms by which O-GlcNAcylation regulates CD36 expression. Membrane protein extraction, immunofluorescence analysis, site-directed mutagenesis, and fatty acid uptake assays were conducted to elucidate the impact of O-GlcNAcylation on CD36 function. ResultsO-GlcNAcylation and CD36 expression were significantly increased in patients with NASH, mouse models of NASH, and palmitic acid-stimulated hepatocytes. Mechanistically, the increase in O-GlcNAcylation facilitated the transcription of CD36 via the NF-κB signalling pathway and stabilized the CD36 protein by inhibiting its ubiquitination, thereby promoting CD36 expression. On the other hand, O-GlcNAcylation facilitated the membrane localization of CD36, fatty acid uptake, and lipid accumulation. However, site-directed mutagenesis of residues S468 and T470 of CD36 reversed these effects. Furthermore, compared with their WT-CD36 counterparts, HFHC-fed S468A&T470A-CD36 mice exhibited decreases in systemic insulin resistance, steatosis severity, inflammation and fibrosis. Pharmacological inhibition of O-GlcNAcylation and CD36 also mitigated the progression of NASH. ConclusionsO-GlcNAcylation promotes the progression of NAFLD by upregulating CD36 expression and function. Inhibition of CD36 O-GlcNAcylation protects against NASH, highlighting a potentially effective therapeutic approach for individuals with NASH.

LincRNA00907 promotes NASH progression by targeting miRNA-942-5p/TAOK1.

The study aims to examine the involvement of lincRNA00907 in the advancement of non-alcoholic steatohepatitis (NASH). The examination was conducted to assess the expression of linc00907 in liver tissues from NASH patients and healthy individuals. High-fat diets induced NASH in mouse models, while palmitic acid/oleic acid treatment was used to create in vitro cell models. Various techniques, such as qRT-PCR, Oil Red O staining and gene knockdown/overexpression, were used to assess the impact of linc00907 on genes related to lipid metabolism and immunity, as well as intracellular lipid accumulation. Furthermore, dual-luciferase reporter assays were carried out to confirm the connection between miRNA-942-5p and linc00907 or TAOK1 mRNA. Linc00907 was found to be significantly upregulated in both NASH patients and NASH mouse models. Overexpression of linc00907 led to an increase in intracellular lipid accumulation, while knockdown of linc00907 resulted in decreased lipid content. It was found that miRNA-942-5p binds with linc00907, and their interaction was confirmed in dual-luciferase reporter assays. Additionally, TAOK1 was predicted to be a downstream target of miRNA-942-5p, and the upregulation of TAOK1 due to linc00907 was reversed by miRNA-942-5p overexpression. linc00907 overexpression reduces apoptosis but can be reversed by TAOK1 knockdown. The reduction of TAOK1 counteracted the impact of linc00907 on gene expression associated with lipid metabolism and immunity, as well as on the accumulation of intracellular lipids. Our research suggests that linc00907 functions as a competitive endogenous RNA (ceRNA) by sequestering miRNA-942-5p, thus increasing the expression of TAOK1 and encouraging lipid accumulation in hepatocytes, leading to the aggravation of NASH development. Targeting the linc00907/miRNA-942-5p/TAOK1 axis may hold therapeutic potential for the treatment of NASH.

An herbal formulation “Shugan Xiaozhi decoction” ameliorates methionine/choline deficiency-induced nonalcoholic steatohepatitis through regulating inflammation and apoptosis-related pathways

Ethnopharmacological relevanceShugan Xiaozhi (SGXZ) decoction is a traditional Chinese medicine used for treating nonalcoholic steatohepatitis (NASH). It has been used clinically for over 20 years and proved to be effective; however, the molecular mechanism underlying the effects of SGXZ decoction remains unclear. Aim of the studyWe analyzed the chemical components, core targets, and molecular mechanisms of SGXZ decoction to improve NASH through network pharmacology and in vivo experiments. Materials and methodsThe chemical components, core targets, and related signaling pathways of SGXZ decoction intervention in NASH were predicted using network pharmacology. Molecular docking was performed to verify chemical components and their core targets. The results were validated in the NASH model treated with SGXZ decoction. Mouse liver function was assessed by measuring ALT and AST levels. TC and TG levels were determined to evaluate lipid metabolism, and lipid deposition was assessed via oil red O staining. Mouse liver damage was determined via microscopy following hematoxylin and eosin staining. Liver fibrosis was assessed via Masson staining. Western blot (WB) and immunohistochemical (IHC) analyses were performed to detect inflammation and the expression of apoptosis-related proteins, including IL-1β, IL-6, IL-18, TNF-α, MCP1, p53, FAS, Caspase-8, Caspase-3, Caspase-9, Bax, Bid, Cytochrome c, Bcl-2, and Bcl-XL. In addition, WB and IHC were used to assess protein expression associated with the TLR4/MyD88/NF-κB pathway. ResultsQuercetin, luteolin, kaempferol, naringenin, and nobiletin in SGXZ decoction were effective chemical components in improving NASH, and TNF-α, IL-6, and IL-1β were the major core targets. Molecular docking indicated that these chemical components and major core targets might interact. KEGG pathway analysis showed that the pathways affected by SGXZ decoction, primarily including apoptosis and TLR4/NF-κB signaling pathways, interfere with NASH. In vivo experiments indicated that SGXZ decoction considerably ameliorated liver damage, fibrosis, and lipid metabolism disorder in MCD-induced NASH mouse models. In addition, WB and IHC verified the underlying molecular mechanisms of SGXZ decoction as predicted via network pharmacology. SGXZ decoction inhibited the activation of apoptosis-related pathways in MCD-induced NASH mice. Moreover, SGXZ decoction suppressed the activation of TLR4/MyD88/NF-κB pathway in MCD-induced NASH mice. ConclusionSGXZ decoction can treat NASH through multiple targets and pathways. These findings provide new insights into the effective treatment of NASH using SGXZ decoction.

Cyclophilin D knockout significantly prevents HCC development in a streptozotocin-induced mouse model of diabetes-linked NASH.

A family of Peptidyl-prolyl isomerases (PPIases), called Cyclophilins, localize to numerous intracellular and extracellular locations where they contribute to a variety of essential functions. We previously reported that non-immunosuppressive pan-cyclophilin inhibitor drugs like reconfilstat (CRV431) or NV556 decreased multiple aspects of non-alcoholic fatty liver disease (NAFLD) in mice under two different non-alcoholic steatohepatitis (NASH) mouse models. Both CRV431 and NV556 inhibit several cyclophilin isoforms, among which cyclophilin D (CypD) has not been previously investigated in this context. It is unknown whether it is necessary to simultaneously inhibit multiple cyclophilin family members to achieve therapeutic benefits or if loss-of-function of one is sufficient. Furthermore, narrowing down the isoform most responsible for a particular aspect of NAFLD/NASH, such as hepatocellular carcinoma (HCC), would allow for more precise future therapies. Features of human diabetes-linked NAFLD/NASH can be reliably replicated in mice by administering a single high dose of streptozotocin to disrupt pancreatic beta cells, in conjunction with a high sugar, high fat, high cholesterol western diet over the course of 30 weeks. Here we show that while both wild-type (WT) and Ppif-/- CypD KO mice develop multipe severe NASH disease features under this model, the formation of HCC nodules was significantly blunted only in the CypD KO mice. Furthermore, of differentially expressed transcripts in a qPCR panel of select HCC-related genes, nearly all were downregulated in the CypD KO background. Cyclophilin inhibition is a promising and novel avenue of treatment for diet-induced NAFLD/NASH. This study highlights the impact of CypD loss-of-function on the development of HCC, one of the most severe disease outcomes.

Lactate transporter MCT1 in hepatic stellate cells promotes fibrotic collagen expression in nonalcoholic steatohepatitis.

Circulating lactate is a fuel source for liver metabolism but may exacerbate metabolic diseases such as nonalcoholic steatohepatitis (NASH). Indeed, haploinsufficiency of lactate transporter monocarboxylate transporter 1 (MCT1) in mice reportedly promotes resistance to hepatic steatosis and inflammation. Here, we used adeno-associated virus (AAV) vectors to deliver thyroxin binding globulin (TBG)-Cre or lecithin-retinol acyltransferase (Lrat)-Cre to MCT1fl/fl mice on a choline-deficient, high-fat NASH diet to deplete hepatocyte or stellate cell MCT1, respectively. Stellate cell MCT1KO (AAV-Lrat-Cre) attenuated liver type 1 collagen protein expression and caused a downward trend in trichrome staining. MCT1 depletion in cultured human LX2 stellate cells also diminished collagen 1 protein expression. Tetra-ethylenglycol-cholesterol (Chol)-conjugated siRNAs, which enter all hepatic cell types, and hepatocyte-selective tri-N-acetyl galactosamine (GN)-conjugated siRNAs were then used to evaluate MCT1 function in a genetically obese NASH mouse model. MCT1 silencing by Chol-siRNA decreased liver collagen 1 levels, while hepatocyte-selective MCT1 depletion by AAV-TBG-Cre or by GN-siRNA unexpectedly increased collagen 1 and total fibrosis without effect on triglyceride accumulation. These findings demonstrate that stellate cell lactate transporter MCT1 significantly contributes to liver fibrosis through increased collagen 1 protein expression in vitro and in vivo, while hepatocyte MCT1 appears not to be an attractive therapeutic target for NASH.

Lactate transporter MCT1 in hepatic stellate cells promotes fibrotic collagen expression in nonalcoholic steatohepatitis

Circulating lactate is a fuel source for liver metabolism but may exacerbate metabolic diseases such as nonalcoholic steatohepatitis (NASH). Indeed, haploinsufficiency of lactate transporter monocarboxylate transporter 1 (MCT1) in mice reportedly promotes resistance to hepatic steatosis and inflammation. Here, we used adeno-associated virus (AAV) vectors to deliver thyroxin binding globulin (TBG)-Cre or lecithin-retinol acyltransferase (Lrat)-Cre to MCT1fl/fl mice on a choline-deficient, high-fat NASH diet to deplete hepatocyte or stellate cell MCT1, respectively. Stellate cell MCT1KO (AAV-Lrat-Cre) attenuated liver type 1 collagen protein expression and caused a downward trend in trichrome staining. MCT1 depletion in cultured human LX2 stellate cells also diminished collagen 1 protein expression. Tetra-ethylenglycol-cholesterol (Chol)-conjugated siRNAs, which enter all hepatic cell types, and hepatocyte-selective tri-N-acetyl galactosamine (GN)-conjugated siRNAs were then used to evaluate MCT1 function in a genetically obese NASH mouse model. MCT1 silencing by Chol-siRNA decreased liver collagen 1 levels, while hepatocyte-selective MCT1 depletion by AAV-TBG-Cre or by GN-siRNA unexpectedly increased collagen 1 and total fibrosis without effect on triglyceride accumulation. These findings demonstrate that stellate cell lactate transporter MCT1 significantly contributes to liver fibrosis through increased collagen 1 protein expression in vitro and in vivo, while hepatocyte MCT1 appears not to be an attractive therapeutic target for NASH.

Vinpocetine represses the progression of nonalcoholic steatohepatitis in mice by mediating inflammasome components via NF-κB signaling

BackgroundInflammasome activation is known to be involved in nonalcoholic steatohepatitis (NASH). Vinpocetine is a derivative of vincamine and is reported to suppress the activation of inflammasome. MethodsThis study explored the therapeutical potential of Vinpocetine on NASH. Mice were fed with a choline-deficient (MCD) or chow diet in the presence or absence of Vinpocetine for 8 weeks. H&E staining and biochemical assays were determined to evaluate the hepatic steatosis and fibrosis symptoms. In addition, primary hepatocytes and Kupffer cells were isolated and induced by MCD or lipopolysaccharides/cholesterol crystals with or without Vinpocetine. ELISAs, qPCR, and Western blotting were applied to determine the levels of NASH-related biomarkers in both in vivo mouse model and in vitro cell models. ResultsTreatment of Vinpocetine did not cause observable side effects against and MCD-induced cells and mouse NASH model. However, treatment of Vinpocetine ameliorated hepatic steatosis and fibrosis and suppressed the levels of alanine transaminase and aspartate transferase in the mouse NASH model. In addition, treatment of Vinpocetine suppressed the mRNA and protein levels of inflammasome components both in vitro and in vivo. ConclusionVinpocetine suppressed NASH in mice by mediating inflammasome components via nuclear factor κB signaling.

Targeting EFHD2 inhibits interferon-γ signaling and ameliorates non-alcoholic steatohepatitis

The precise pathomechanisms underlying the development of nonalcoholic steatohepatitis (NASH, also known as metabolic dysfunction-associated steatohepatitis [MASH]) remain incompletely understood. This study investigates the potential role of EF-hand domain family member D2 (EFHD2), a novel molecule specific to immune cells, in NASH pathogenesis. Hepatic EFHD2 expression was characterized in NASH patients and two diet-induced NASH mouse models. Single-cell RNA-sequencing (scRNA-seq) and double-immunohistochemistry were employed to explore EFHD2 expression patterns in NASH livers. The effects of global and myeloid-specific EFHD2 deletion on NASH and NASH-related hepatocellular carcinoma (HCC) were assessed. Molecular mechanisms underlying EFHD2 function were investigated, along with its potential as a therapeutic target by chemical and genetic means. EFHD2 expression was significantly elevated in liver tissue macrophages/monocytes in both NASH patients and mice. Deletion of EFHD2, either globally or specifically in myeloid cells, improved hepatic steatosis, reduced immune cell infiltration, inhibited lipid peroxidation-induced ferroptosis, and attenuated fibrosis in NASH. Additionally, it hindered the development of NASH-related HCC. Specifically, deletion of myeloid EFHD2 prevented the replacement of TIM4+ resident Kupffer cells by infiltrated monocytes and reversed the decreases in patrolling monocytes and CD4+/CD8+ T cell ratio in NASH. Mechanistically, our investigation revealed that EFHD2 in myeloid cells interacts with cytosolic YWHAZ (14-3-3ζ), facilitating the translocation of interferon-γ receptor-2 (IFNγR2) onto the plasma membrane. This interaction mediates IFNγ signaling, which triggers immune and inflammatory responses in macrophages during NASH. Finally, a developed stapled α-helical peptide targeting EFHD2 demonstrated its efficacy in protecting against NASH pathology in mice. Our study reveals a pivotal immunomodulatory and inflammatory role of EFHD2 in NASH, underscoring EFHD2 as a promising druggable target for NASH treatment. Nonalcoholic steatohepatitis (NASH) represents an advanced stage of non-alcoholic fatty liver disease (NAFLD); however, not all NAFLD patients progress to NASH. A key challenge is identifying the factors triggering inflammation, which propels the transition from simple fatty liver to NASH. Our research pinpointed EFHD2 as a pivotal driver of NASH, orchestrating the over-activation of IFNγ signaling within the liver during NASH progression. A stapled peptide designed to target EFHD2 exhibited therapeutic promise in NASH mice. These findings suggest EFHD2 as a promising target for drug development aimed at NASH treatment.

Longitudinal Magnetic Resonance Imaging with ROS-Responsive Bilirubin Nanoparticles Enables Monitoring of Nonalcoholic Steatohepatitis Progression to Cirrhosis.

Despite the vital importance of monitoring the progression of nonalcoholic fatty liver disease (NAFLD) and its progressive form, nonalcoholic steatohepatitis (NASH), an efficient imaging modality that is readily available at hospitals is currently lacking. Here, a new magnetic-resonance-imaging (MRI)-based imaging modality is presented that allows for efficient and longitudinal monitoring of NAFLD and NASH progression. The imaging modality uses manganese-ion (Mn2+)-chelated bilirubin nanoparticles (Mn@BRNPs) as a reactive-oxygen-species (ROS)-responsive MRI imaging probe. Longitudinal T1-weighted MR imaging of NASH model mice is performed after injecting Mn@BRNPs intravenously. The MR signal enhancement in the liver relative to muscle gradually increases up to 8 weeks of NASH progression, but decreases significantly as NASH progresses to the cirrhosis-like stage at weeks 10 and 12. A new dual input pseudo-three-compartment model is developed to provide information on NASH stage with a single MRI scan. It is also demonstrated that the ROS-responsive Mn@BRNPs can be used to monitor the efficacy of potential anti-NASH drugs with conventional MRI. The findings suggest that the ROS-responsive Mn@BRNPs have the potential to serve as an efficient MRI contrast for monitoring NASH progression and its transition to the cirrhosis-like stage.

Corn Oligopeptide Alleviates Nonalcoholic Fatty Liver Disease by Regulating the Sirtuin Signaling Pathway.

Nonalcoholic fatty liver disease (NAFLD) represents the most prevalent type of chronic liver disease, spanning from simple steatosis to nonalcoholic steatohepatitis (NASH). Corn oligopeptide (CP) is a functional peptide known for its diverse pharmacological effects on metabolism. In this study, we evaluated the protective activity of CP against fatty liver disease. Oral administration of CP significantly reduced body weight gain by 2.95%, serum cholesterol by 22.54%, and liver injury, as evidenced by a reduction of 32.19% in serum aspartate aminotransferase (AST) and 49.10% in alanine aminotransferase (ALT) levels in mice subjected to a high-fat diet (HFD). In a streptozotocin/HFD-induced NASH mouse model, CP attenuated body weight gain by 5.11%, liver injury (with a 34.15% decrease in AST and 11.43% decrease in ALT), and, to some extent, liver inflammation and fibrosis. Proteomic analysis revealed the modulation of oxidative phosphorylation and sirtuin (SIRT) signaling pathways by CP. Remarkably, CP selectively inhibited the hepatic expression of mitochondrial SIRT3 and SIRT5 in both HFD and NASH models. In summary, CP demonstrates a preventive effect against metabolic-stress-induced NAFLD progression by modulating oxidative stress and the SIRT signaling pathway, suggesting the potential of CP as a therapeutic agent for the treatment of NAFLD and advanced-stage NASH.

Perturbed liver gene zonation in a mouse model of non-alcoholic steatohepatitis

Liver zonation characterizes the separation of metabolic pathways along the lobules and is required for optimal hepatic function. Wnt signaling is a master regulator of spatial liver zonation. A perivenous-periportal Wnt activity gradient orchestrates metabolic zonation by activating gene expression in perivenous hepatocytes, while suppressing gene expression in their periportal counterparts. However, the understanding as to the liver gene zonation and zonation regulators in diseases is limited. Non-alcoholic steatohepatitis (NASH) is a chronic liver disease characterized by fat accumulation, inflammation, and fibrosis. Here, we investigated the perturbation of liver gene zonation in a mouse NASH model by combining spatial transcriptomics, bulk RNAseq and in situ hybridization. Wnt-target genes represented a major subset of genes showing altered spatial expression in the NASH liver. The altered Wnt-target gene expression levels and zonation spatial patterns were in line with the up regulation of Wnt regulators and the augmentation of Wnt signaling. Particularly, we found that the Wnt activator Rspo3 expression was restricted to the perivenous zone in control liver but expanded to the periportal zone in NASH liver. AAV8-mediated RSPO3 overexpression in controls resulted in zonation changes, and further amplified the disturbed zonation of Wnt-target genes in NASH, similarly Rspo3 knockdown in Rspo3+/− mice resulted in zonation changes of Wnt-target genes in both chow and HFD mouse. Interestingly, there were no impacts on steatosis, inflammation, or fibrosis NASH pathology from RSPO3 overexpression nor Rspo3 knockdown. In summary, our study demonstrated the alteration of Wnt signaling in a mouse NASH model, leading to perturbed liver zonation.

Integrative analysis identifies oxidative stress biomarkers in non-alcoholic fatty liver disease via machine learning and weighted gene co-expression network analysis.

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease globally, with the potential to progress to non-alcoholic steatohepatitis (NASH), cirrhosis, and even hepatocellular carcinoma. Given the absence of effective treatments to halt its progression, novel molecular approaches to the NAFLD diagnosis and treatment are of paramount importance. Firstly, we downloaded oxidative stress-related genes from the GeneCards database and retrieved NAFLD-related datasets from the GEO database. Using the Limma R package and WGCNA, we identified differentially expressed genes closely associated with NAFLD. In our study, we identified 31 intersection genes by analyzing the intersection among oxidative stress-related genes, NAFLD-related genes, and genes closely associated with NAFLD as identified through Weighted Gene Co-expression Network Analysis (WGCNA). In a study of 31 intersection genes between NAFLD and Oxidative Stress (OS), we identified three hub genes using three machine learning algorithms: Least Absolute Shrinkage and Selection Operator (LASSO) regression, Support Vector Machine - Recursive Feature Elimination (SVM-RFE), and RandomForest. Subsequently, a nomogram was utilized to predict the incidence of NAFLD. The CIBERSORT algorithm was employed for immune infiltration analysis, single sample Gene Set Enrichment Analysis (ssGSEA) for functional enrichment analysis, and Protein-Protein Interaction (PPI) networks to explore the relationships between the three hub genes and other intersecting genes of NAFLD and OS. The distribution of these three hub genes across six cell clusters was determined using single-cell RNA sequencing. Finally, utilizing relevant data from the Attie Lab Diabetes Database, and liver tissues from NASH mouse model, Western Blot (WB) and Reverse Transcription Quantitative Polymerase Chain Reaction (RT-qPCR) assays were conducted, this further validated the significant roles of CDKN1B and TFAM in NAFLD. In the course of this research, we identified 31 genes with a strong association with oxidative stress in NAFLD. Subsequent machine learning analysis and external validation pinpointed two genes: CDKN1B and TFAM, as demonstrating the closest correlation to oxidative stress in NAFLD. This investigation found two hub genes that hold potential as novel targets for the diagnosis and treatment of NAFLD, thereby offering innovative perspectives for its clinical management.