Progression Of Nonalcoholic Steatohepatitis Research Articles

Correction of the clinical course of non-alcoholic steatohepatitis and diabetic kidney disease in patients with type 2 diabetes

Background. The relevance of finding optimal methods to treat patients with a comorbid non-alcoholic steatohepatitis (NASH) that developed against the background of type 2 diabetes mellitus (T2DM) is due to the fact that these diseases have a number of common cause-and-effect mechanisms, and if diabetic kidney disease (DKD) develops, also mutual burden mechanisms. The purpose of the study was to find out the possible influence of a combination of metformin, rosuvastatin, essential phospholipids and quercetin on the clinical course of non-alcoholic steatohepatitis, diabetic kidney disease, type 2 diabetes mellitus, as well as on the state of the blood lipids, parameters of carbohydrate metabolism compensation, the degree of insulin resistance, which are factors for the progression of NASH and diabetic kidney disease. Materials and methods. Studies were conducted on the dynamics of treatment in 60 patients with NASH, T2DM and DKD stage I–III: 48 (80.0 %) of them had mild NASH, and 12 (20.0 %) had moderate NASH. A comorbid disease in 100 % of patients was moderate type 2 diabetes: 15 (25.0 %) people were diagnosed with diabetes in the stage of compensation, 45 (75.0 %) had subcompensated disease. Results. The positive effect of quercetin was noted by us in relation to the content of low-density lipoprotein cholesterol in the blood that was increased by 1.8 times (p < 0.05) before the treatment: a decrease after it was 1.7 times (p < 0.05) in group 2 and 1.3 times (p < 0.05) in group 1. Comprehensive therapy with the inclusion of quercetin contributed to a probable increase in anti-atherogenic high-density lipoprotein (by 1.3 times, p < 0.05) with the normalization of the indicator after the treatment, while traditional therapy in this contingent did not lead to any probable changes. Conclusions. The combination therapy for type 2 diabetes mellitus and NASH with the addition of quercetin contributed to the elimination of the main clinical and laboratory symptoms of NASH exacerbation, a probable reduction in the liver inflammation (a decrease in markers of cytolysis, mesenchymal inflammation), reversal of hepatic steatosis due to the optimization of cholesterol and triacylglycerols in the blood, a probable increase in high-density lipoproteins, normalization of glycemia, reduction of insulinemia, a decrease in the degree of insulin resistance. The effectiveness of treatment for DKD was also increased: the rate of proteinuria and the degree of hypercreatinemia decreased, and the glomerular filtration rate increased.

Platelet-derived mitochondria regulate lipid metabolism in nonalcoholic steatohepatitis via extracellular vesicles.

Immune system activation along with lipotoxicity due to excessive lipid droplet (LD) accumulation in the liver are key drivers of non-alcoholic steatohepatitis (NASH). Extracellular vesicles (EVs) released by cells that carry biological signals to contribute intercellular communication. But the roles of immune cells-derived EVs in pathogenesis of NASH are unclear. Platelets are abundant in blood. We explored the role of platelet-derived EVs (pEVs) in LD accumulation from 30 patients with non-alcoholic fatty liver disease of different severity as well as 20 healthy subjects, a rat model, and an in vitro cell-based assay. There was increased platelet activation, accompanied by pEVs release, in NASH patients/rat model, and palmitate-treated cells. The mitochondria in the platelets and pEVs from NASH patients/rats were increased but dysfunctional, including a reduction in fatty acid β-oxidation, inactivated ACC2, and suppressed oxidative phosphorylation system complex II/III/IV activity. These damaged mitochondria could be transferred to hepatocytes via pEVs to increase the number of lipid droplet-bound mitochondria (LDM). An increase in dysfunctional LDM in hepatocytes affects lipid metabolism, resulting in excessive LD accumulation, elevated mitochondrial ROS production, and apoptosis. We offer a novel molecular mechanism that connects platelets, pEVs, and excessive LD accumulation to the development of NASH. Our results suggest that NASH progression may be alleviated by specifically inhibiting the production and release of pEVs, or by targeting pEVs components and inhibiting their uptake. Additional experiments are required to confirm this potentiality.

The methyltransferase MLL4 promotes non-alcoholic steatohepatitis by enhancing NF-κB signaling.

Non-alcoholic fatty liver disease (NAFLD) is a growing health problem worldwide, ranging from non-alcoholic fatty liver (NAFL) to the more severe metabolic non-alcoholic steatohepatitis (NASH). Although many studies have elucidated the pathogenesis of NAFLD, the epigenetic regulatory mechanism from NAFL to NASH remains incompletely understood. The histone H3 lysine 4 methyltransferase, MLL4 (also called KMT2D), is a critical epigenetic transcriptional coactivator that mediates overnutrition-induced steatosis in mice, but its potential role in the progression of NASH remains largely unknown. Here, we show that mice lacking the one allele of the Mll4 gene are resistant to hepatic steatosis, inflammation, and fibrosis in NASH conditions compared to wild-type controls. Transcriptome analysis of the livers of control and Mll4+/- mice identified pro-inflammatory genes regulated by the nuclear factor kappa B (NF-κB) signaling pathway as major target genes of MLL4. We show that MLL4 binds to p65 and that MLL4 is required for NF-κB transactivation. Myeloid-specific Mll4 knockout mice showed an almost complete block of NASH, while hepatocyte-specific Mll4 knockout mice showed mild inhibition of steatosis. Pro-inflammatory M1 polarization is decreased and anti-inflammatory M2 polarization is increased in liver macrophages from myeloid-specific Mll4 knockout mice. Importantly, we show that histone H3-lysine 4 methylation mediated by the MLL4-complex plays a critical role in promoting the expression of Ccl2 in hepatocytes and M1 marker genes in macrophages. Our results demonstrate that MLL4, through the NF-κB-MLL4 regulatory axis, exacerbates steatohepatitis in the context of an inflammatory response and represents a potential therapeutic target for NASH.

Protective effect of alpha-tocopherol on lipogenesis and oxysterol production in hypercholesterolemia-induced nonalcoholic Steatohepatitis

Despite limited number of studies, oxysterols are known to contribute to the progression of nonalcoholic steatohepatitis (NASH) by affecting lipid/cholesterol metabolism and elevating proinflammatory and profibrotic processes. Accordingly, we used a high cholesterol-mediated in vivo NASH model and aimed to determine alterations in fatty acid content and oxysterol levels together with their effects on cholesterol/lipid metabolism during the progression of the disease. We further investigated the beneficial role of α-tocopherol. To this end, in our hypercholesterolemic rabbit model, we determined fatty acid profile by GC–MS while 25-, 27-, 4β-, 7α, and 24(S)-Hydroxycholesterol levels by means of LC–MS/MS. Additionally, lipid (SREBP-1c, PPARα, PPARγ) and cholesterol metabolism-related proteins (LXRα, SREBP2 and ABCA1) were determined by immunoblotting. In conclusion, the present findings provide a complete analysis of the hepatic alterations in lipid and oxysterol profiles mediated by a high-cholesterol diet. In addition, this study explains the protective effect of α-tocopherol on lipogenesis and oxysterol production in hypercholesterolemia-induced NASH. We believe that present study will guide to novel theories in the progression and therapeutic targeting of fatty liver diseases.

Exosomes derived from apical papilla stem cells improve NASH by regulating fatty acid metabolism and reducing inflammation

BackgroundApical papilla stem cells (SCAPs) exhibit significant potential for tissue repair, characterized by their anti-inflammatory and pro-angiogenic properties. Exosomes derived from stem cells have emerged as safer alternatives that retain comparable physiological functions. This study explores the therapeutic potential of exosomes sourced from SCAPs in the treatment of non-alcoholic steatohepatitis (NASH).MethodsA NASH mouse model was established through the administration of a high-fat diet (HFD), and SCAPs were subsequently isolated for experimental purposes. A cell model of NASH was established in vitro by treating hepatocellular carcinoma cells with oleic acid (OA) and palmitic acid (PA). Exosomes were isolated via differential centrifugation. The mice were treated with exosomes injected into the tail vein, and the hepatocytes were incubated with exosomes in vitro. After the experiment, physiological and biochemical markers were analyzed to assess the effects of exosomes derived from SCAPs on the progression of NASH in both NASH mouse models and NASH cell models.ResultsAfter exosomes treatment, the weight gain and liver damage induced by HFD were significantly reduced. Additionally, hepatic fat accumulation was markedly alleviated. Mechanistically, exosomes treatment promoted the expression of genes involved in hepatic fatty acid oxidation and transport, while simultaneously suppressing genes associated with fatty acid synthesis. Furthermore, the levels of serum inflammatory cytokines and the mRNA expression of inflammatory markers in liver tissue were significantly decreased. In vitro cell experiments produced similar results.

The Nr4a family regulates intrahepatic Treg proliferation and liver fibrosis in MASLD models.

Nonalcoholic steatohepatitis (NASH) is a chronic progressive liver disease and highly prevalent worldwide. NASH is characterized by hepatic steatosis, inflammation, fibrosis and liver damage, which eventually results in liver dysfunction due to cirrhosis or hepatocellular carcinoma. However, the cellular and molecular mechanisms underlying NASH progression remain largely unknown. Here, we found an increase of Nr4a family of orphan nuclear receptors expression in intrahepatic T cells from mice with diet-induced NASH. Loss of Nr4a1 and Nr4a2 in T cell (dKO) ameliorated liver cell death and fibrosis, thereby mitigating liver dysfunction in NASH mice. dKO resulted in reduction of infiltrated macrophages and Th1/Th17 cells, whereas massive accumulation of T regulatory (Treg) cells in the liver of NASH mice. Combined single-cell RNA transcriptomic and TCR sequencing analysis revealed that intrahepatic dKO Tregs exhibited enhanced TIGIT and IL10 expression and were clonally expanded during NASH progression. Mechanistically, we found that dKO Tregs expressed high levels of Batf which promotes Treg cell proliferation and function upon TCR stimulation. Collectively, our findings not only provide an insight into the impact of intrahepatic Treg cells on NASH pathogenesis, but also suggest a therapeutic potential of targeting of Nr4a family to treat the disease.

6824 Bile Acid Elevation in Nonalcoholic Steatohepatitis Correlates With Fibrogenesis and Mitochondrial Dysfunction In Vitro

Abstract Disclosure: N. Patel: None. Y. Li: None. M. Raul: None. C. Sottas: None. V. Papadopoulos: None. Nonalcoholic steatohepatitis (NASH) is the most severe form of nonalcoholic fatty liver disease. It is estimated that over 115 million adults are affected by NASH worldwide. The causes of NASH are unclear, and no treatment is yet available. Bile acids (BAs) are steroids synthesized in the liver, promoting lipid absorption. The levels of BAs are tightly regulated in the body. Patients diagnosed with NASH frequently exhibit increased levels of BAs in both liver tissue and plasma, indicating a potential association between elevated BA concentrations and the pathogenesis of NASH. In an in vivo study using a high-fat diet rat model of NASH, we measured plasma BA composition and levels. The results obtained indicated substantial increases in the concentrations of glycocholic acid (GCA), glycochenodeoxycholic acid (GCDCA), glycodeoxycholic acid (GDCA), and taurodeoxycholic acid (TDCA) in NASH compared to controls. These findings suggested their potential implication in the development of NASH. To elucidate the mechanistic link between changes in BA synthesis and fibrogenesis, in vitro experiments were conducted using the LX-2 humane hepatic stellate and Huh7 human hepatocellular carcinoma cells. First, the concentrations of the selected bile acids (GCA, GCDCA, GDCA, and TDCA) used in our studies were found to be non-toxic to the cells using the MTT assay. Subsequent qPCR analyses demonstrated the upregulation of key fibrotic genes (TGFβ, COL1A1, ACTA2) in LX-2 cells following exposure to individual bile acids GCA, GCDCA, GDCA, and TDCA. Immunocytochemistry (ICC) studies further demonstrated fibrogenesis by revealing increased expression of COL1A1 following treatment with each of the four bile acids. These data suggest that changes in BA formation are linked to fibrogenesis. We subsequently explored the impact of BAs on mitochondrial function using the Seahorse XF Cell Mito Stress Test in Huh7 cells. The results obtained revealed a reduction in the oxygen consumption rate and ATP production in response to BA treatment. This observation suggests a potential role for modified BAs in disrupting mitochondrial homeostasis, a recognized contributor to the progression of NASH. In summary, the data presented provide valuable insights into the complex effects of modified BAs on NASH pathogenesis, establishing connections between changes in BA composition and fibrogenesis, mitochondrial dysfunction. Presentation: 6/2/2024

6681 Age and Sex Disparity in NASH and the Potential Role of Estradiol Treatment for NASH

Abstract Disclosure: M. Tripathi: None. S. Sakthivel: None. A. Suzuki: None. B.K. Singh: None. P.M. Yen: None. Introduction: NAFLD (nonalcoholic fatty liver disease) and its more severe form, NASH (nonalcoholic steatohepatitis) are sexually dimorphic conditions that exhibit higher prevalence in men than women during reproductive ages but have similar prevalence after menopause. Reproductive age women are protected from hepatic fibrosis relative to men, although they lose this protection after menopause. These sex differences in NASH have been attributed, at least partly, to different circulating estrogen levels. However, the underlying mechanism(s) is not fully understood. We thus conducted animal experiments to investigate: 1) sex differences in the histologic severity of NASH, necroinflammatory and fibrogenic activities, and other relevant pathways in young and old male and female mice and 2) the effects of estradiol administration on these parameters in old male and female mice to evaluate the therapeutic potential of estradiol in NASH. Methodology: Young/reproductive age (12-weeks old) and old/post-reproductive age female and male (48∼50-weeks weeks old) C57BL/6J mice were fed control chow diet (NCD) or high-fat methionine/choline-deficient (MCD) diet for six weeks to induce NASH. The old mice were administered 200nM 17β-estradiol (physiological) in drinking water. We analyzed serum and hepatic NASH parameters, ER stress, and lysosome-autophagy defects. Results and Conclusion: Among reproductive age mice with NASH, females developed less severe histologic inflammation and fibrosis and decreased gene expression of Il1b, Il6, Tgfb, Col1a1, Ccl2, and Ccl5, and lower hepatic collagen than males. Females with NASH also had less inhibition of hepatic autophagy and lysosomal protein expression than males with NASH. Among old mice, post-reproductive age females fed NCD or MCD exhibited more severe hepatic inflammation and fibrosis and had higher gene expression of inflammatory and fibrogenic markers with comparable autophagic inhibition and lysosomal defects as similar age males. Physiological doses of estradiol significantly reduced hepatic gene expression of inflammatory and fibrogenic markers, ER stress and lysosomal-autophagic defects in post-reproductive age females. In conclusion, similar to clinical NASH, we observed marked sex and age-related differences in the severity of NASH. Furthermore, physiological doses of estradiol treatment improved the hepatic histology, lysosome-autophagy, inflammation, and fibrosis in post-reproductive age female mice with NASH and suggests that estradiol supplementation may decrease or reverse NASH progression in post-menopausal women with NASH. Presentation: 6/2/2024

PDCD4 deficiency in hepatocytes exacerbates nonalcoholic steatohepatitis through enhanced MHC class II transactivator expression

Nonalcoholic steatohepatitis (NASH) is a primary cause of liver cirrhosis and hepatocellular carcinoma, presenting a significant and unmet medical challenge. The necessity to investigate the molecular mechanisms underlying NASH is highlighted by the observed decrease in programmed cell death 4 (PDCD4) expression in NASH patients, suggesting that PDCD4 may play a protective role in maintaining liver health. In this study, we identify PDCD4 as a natural inhibitor of NASH development in mice. The absence of PDCD4 leads to the spontaneous progression of NASH. Notably, PDCD4-deficient hepatocytes display elevated major histocompatibility complex class II (MHCII) expression due to CIITA activation, indicating that PCDC4 prevents the abnormal transformation of hepatocytes into antigen-presenting cells (APCs). Cell co-culture experiments reveal that hepatocytes lacking PDCD4, which resemble APCs, can directly activate CD4+ T cells by presenting multiple peptides, resulting in the release of inflammatory factors. Additionally, both cellular and animal studies show that CIITA promotes lipid accumulation in hepatocytes and exacerbates NASH progression. In summary, our findings reveal a novel role of PDCD4 in regulating CIITA and MHCII expression during NASH development, offering new therapeutic approaches for NASH treatment.

Progression from Non-alcoholic Steatohepatitis to Advanced Liver Diseases and Mortality Among Medicare Patients.

Non-alcoholic steatohepatitis (NASH) may progress to more advanced liver disease. This study aimed to characterize NASH progression and mortality in the Medicare population. Patients with NASH in 100% Medicare fee-for-service claims accrued from2015-2021 who were≥66years old at index diagnosis, continuously enrolled for≥12months prior to and≥6months following index (unless death), and had no evidence of other causes of liver disease were included. Diagnosis codes defined severity states: non-cirrhotic NASH, compensated cirrhosis (CC), decompensated cirrhosis (DCC), hepatocellular carcinoma (HCC), and liver transplant (LT). Survival analyses of disease progression and mortality were conducted for each state and by year of progression (Y1-5). Cox proportional hazards models assessed risk factors of worsening disease. Mean age and follow-up were 72.2 and 2.8years in 14,806 unique patients (n=12,990 NASH; 1899 CC; 997 DCC; 209 HCC; 140 LT). Progression rates were highest for patients with CC (11-37% for Y1-5), followed by DCC (3-18%), NASH (3-12%), and HCC (2-4%). Mortality rates were highest for patients with HCC (41-85% for Y1-5), followed by DCC (41-76%), LT (7-33%), CC (6-26%), and NASH (2-12%). Patients with any disease progression had a 5-year mortality rate more than double that of patients without progression (41% vs. 16%). Delayed progression from NASH was associated with lower mortality risk; the 5-year mortality rate was 26% lower for patients with progression in Y2 vs. Y1 (32% vs. 43%) and further decreased for progression in Y3-Y5. Risk factors included age, nursing home use, congestive heart failure, coagulopathy, fluid/electrolyte disorders, and unexplained weight loss. Medicare patients≥66years with NASH experience high risk of disease progression associated with increased mortality rates. Slower disease progression is associated with lower mortality rates, suggesting that therapies that can delay or prevent NASH progression may reduce morbidity and mortality.

Elucidation of the molecular mechanism of type 2 diabetes mellitus affecting the progression of nonalcoholic steatohepatitis using bioinformatics and network pharmacology: A review.

Increasing evidence suggests that patients with diabetes are at increased risk of developing nonalcoholic steatohepatitis (NASH), but the underlying mechanisms that affect the progression of NASH remain unclear. In this study, we used bioinformatics and network pharmacology methods to explore the differentially expressed genes of NASH and the related genes of type 2 diabetes mellitus, and a total of 46 common targets were obtained. Gene ontology showed that the common targets were mainly involved in biological processes such as glucocorticoid, hormone, and bacterium responses. The Kyoto Encyclopedia of Genes and Genomes enrichment analysis signal pathways were mainly in colorectal cancer, amphetamine addition, the peroxisome proliferator-activated receptor signaling pathway, and the toll-like receptor signaling pathway. The protein-protein interaction network identified 8 hub genes, and the co-expression network was analyzed to obtain 7 related functions and mutual proportions of hub genes. A total of 120 transcription factors were predicted for hub genes. Hub genes were closely related to immune cells, including neutropils and eosinophils. In addition, we identified 15 potential candidate drugs based on hub genes that are promising for the treatment of NASH. Type 2 diabetes mellitus can affect the progression of NASH by changing hormone levels and inflammatory responses through multiple targets and signaling pathways. Eight hub genes are expected to be potential targets for subsequent treatment.

GTPBP8 mitigates nonalcoholic steatohepatitis (NASH) by depressing hepatic oxidative stress and mitochondrial dysfunction via PGC-1α signaling

Nonalcoholic steatohepatitis (NASH) is emerging as a major cause of liver transplantation and hepatocellular carcinoma (HCC). Regrettably, its pathological mechanisms are still not fully comprehended. GTP-binding protein 8 (GTPBP8), belonging to the GTP-binding protein superfamily, assumes a crucial role in RNA metabolism, cell proliferation, differentiation, and signal transduction. Its aberrant expression is associated with oxidative stress and mitochondrial dysfunctions. Nevertheless, its specific functions and mechanisms of action, particularly in NASH, remain elusive. In our current study, we initially discovered that human hepatocytes L02 displayed evident mitochondrial respiratory anomaly, mitochondrial damage, and dysfunction upon treatment with palmitic acids and oleic acids (PO), accompanied by significantly reduced GTPBP8 expression levels through RNA-Seq, RT-qPCR, western blotting, and immunofluorescence assays. We then demonstrated that GTPBP8 overexpression mediated by adenovirus vector (Ad-GTPBP8) markedly attenuate lipid accumulation, inflammatory response, and mitochondrial impair and dysfunction in hepatocytes stimulated by PO. Conversely, adenovirus vector-mediated GTPBP8 knockdown (Ad-shGTPBP8) significantly accelerated lipid deposition, inflammation and mitochondrial damage in PO-treated hepatocytes in vitro. Furthermore, we constructed an in vivo NASH murine model by giving a 16-week high fat high cholesterol diet (HFHC) diet to hepatocyte specific GTPBP8-knockout (GTPBP8HKO) mice. We firstly found that HFHC feeding led to metabolic disorder in mice, including high body weight, blood glucose and insulin levels, and liver dysfunctions, which were accelerated in these NASH mice with GTPBP8 deficiency in hepatocytes. Consistently, GTPBP8HKO remarkably exacerbated the progression of NASH phenotypes induced by HFHC, as proved by the anabatic lipid accumulation, inflammation, fibrosis and reactive oxygen species (ROS) production in liver tissues, which could be largely attributed to the severe mitochondrial damage and dysfunction. Mechanistically, we further identified that GTPBP8 interacted with peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) in hepatocytes. Importantly, the hepaprotective effects of GTPBP8 against mitochondrial dysfunction, oxidative stress and inflammation was largely dependent on PGC-1α expression. Collectively, GTPBP8 may exert a protective role in the progression of NASH, and targeting the GTPBP8/PGC-1α axis may represent a potential strategy for NASH treatment by improving mitochondrial functions.

Ginger essential oil prevents NASH progression by blocking the NLRP3 inflammasome and remodeling the gut microbiota-LPS-TLR4 pathway in mice

BackgroundDiet and gut microbiota contribute to non-alcoholic steatohepatitis (NASH) progression. High-fat diets (HFDs) change gut microbiota compositions, induce gut dysbiosis, and intestinal barrier leakage, which facilitates portal influx of pathogen-associated molecular patterns including lipopolysaccharides (LPS) to the liver and triggers inflammation in NASH. Current therapeutic drugs for NASH have adverse side effects; however, several foods and herbs that exhibit hepatoprotection could be an alternative method to prevent NASH.MethodsWe investigated ginger essential oil (GEO) against palm oil-containing HFDs in LPS-injected murine NASH model.ResultsGEO reduced plasma alanine aminotransferase levels and hepatic pro-inflammatory cytokine levels; and increased antioxidant catalase, glutathione reductase, and glutathione levels to prevent NASH. GEO alleviated hepatic inflammation through mediated NLR family pyrin domain-containing 3 (NLRP3) inflammasome and LPS/Toll-like receptor four (TLR4) signaling pathways. GEO further increased beneficial bacterial abundance and reduced NASH-associated bacterial abundance.ConclusionThis study demonstrated that GEO prevents NASH progression which is probably associated with the alterations of gut microbiota and inhibition of the LPS/TLR4/NF-κB pathway. Hence, GEO may offer a promising application as a dietary supplement for the prevention of NASH.

A novel experimental mouse model of diabetic nonalcoholic steatohepatitis: A critical role for acid-sensitive Ion Channel 1a

BackgroundA two-way relationship exists between type 2 diabetes (T2DM) and human nonalcoholic steatohepatitis (NASH). Several diabetic NASH models have the disadvantages of long cycles or inconsistent with the actual incidence of human disease, which would be costly and time-consuming to investigate disease pathogenesis and develop drugs. Therefore, there is an urgent need to establish a diabetic NASH mouse model. MethodsThe combination between Fructose-palmitate-cholesterol diet (FPC) and Streptozotocin (STZ) (FPC+STZ) was used to construct diabetic NASH mouse model. The in vivo effects of silencing acid-sensitive Ion Channel 1a (ASIC1a) were examined with an adeno-associated virus 9 (AAV9) carrying ASIC1a short hairpin RNA (shRNA) in FPC+STZ model. ResultsThe mice fed with FPC for 12 weeks had insulin resistance, hyperinsulinemia, lipid accumulation, and increased hepatic levels of inflammatory factors. However, it still did not develop remarkable liver fibrosis. Most interestingly, noticeable fibrotic scars were observed in the liver of mice from FPC+STZ group. Furthermore, insulin therapy significantly ameliorated FPC+STZ-induced NASH-related liver fibrosis, indicating that hyperglycemia is of great significance in NASH development and progression. Importantly, ASIC1a was found to be involved in the pathogenesis of diabetic NASH as demonstrated that silencing ASIC1a in HSCs significantly ameliorated FPC+STZ-induced NASH fibrosis. Mechanistically, ASIC1a interacted with Poly Adp-adenosine ribose polymerase (PARP1) to promote HSC activation by inducing autophagy. ConclusionA FPC diet combined with an injection of STZ induces a diabetic NASH mouse model in a shorter period. Targeting ASIC1a may provide a novel therapeutic target for the treatment of diabetic NASH.

The Foxo1-YAP-Notch1 axis reprograms STING-mediated innate immunity in NASH progression

Innate immune activation is critical for initiating hepatic inflammation during nonalcoholic steatohepatitis (NASH) progression. However, the mechanisms by which immunoregulatory molecules recognize lipogenic, fibrotic, and inflammatory signals remain unclear. Here, we show that high-fat diet (HFD)-induced oxidative stress activates Foxo1, YAP, and Notch1 signaling in hepatic macrophages. Macrophage Foxo1 deficiency (Foxo1M-KO) ameliorated hepatic inflammation, steatosis, and fibrosis, with reduced STING, TBK1, and NF-κB activation in HFD-challenged livers. However, Foxo1 and YAP double knockout (Foxo1/YAPM-DKO) or Foxo1 and Notch1 double knockout (Foxo1/Notch1M-DKO) promoted STING function and exacerbated HFD-induced liver injury. Interestingly, Foxo1M-KO strongly reduced TGF-β1 release from palmitic acid (PA)- and oleic acid (OA)-stimulated Kupffer cells and decreased Col1α1, CCL2, and Timp1 expression but increased MMP1 expression in primary hepatic stellate cells (HSCs) after coculture with Kupffer cells. Notably, PA and OA challenge in Kupffer cells augmented LIMD1 and LATS1 colocalization and interaction, which induced YAP nuclear translocation. Foxo1M-KO activated PGC-1α and increased nuclear YAP activity, modulating mitochondrial biogenesis. Using chromatin immunoprecipitation (ChIP) coupled with massively parallel sequencing (ChIP-Seq) and in situ RNA hybridization, we found that NICD colocalizes with YAP and targets Mb21d1 (cGAS), while YAP functions as a novel coactivator of the NICD, which is crucial for reprogramming STING function in NASH progression. These findings highlight the importance of the macrophage Foxo1–YAP–Notch1 axis as a key molecular regulator that controls lipid metabolism, inflammation, and innate immunity in NASH.

Protective Effect of Caffeine and Chlorogenic Acids of Coffee in Liver Disease.

Coffee is one of the most widely consumed beverages in the world due to its unique aroma and psychostimulant effects, mainly due to the presence of caffeine. In recent years, experimental evidence has shown that the moderate consumption of coffee (3/4 cups per day) is safe and beneficial to human health, revealing protective effects against numerous chronic metabolic diseases such as diabetes, cardiovascular, neurodegenerative, and hepatic diseases. This review focuses on two of coffee's main bioactive compounds, i.e., caffeine and chlorogenic acids, and their effects on the progression of chronic liver diseases, demonstrating that regular coffee consumption correlates with a lower risk of the development and progression of non-alcoholic steatohepatitis, viral hepatitis, liver cirrhosis, and hepatocellular carcinoma. In particular, this review analyzes caffeine and chlorogenic acid from a pharmacological point of view and explores the molecular mechanism through which these compounds are responsible for the protective role of coffee. Both bioactive compounds, therefore, have antifibrotic effects on hepatic stellate cells and hepatocytes, induce a decrease in connective tissue growth factor, stimulate increased apoptosis with anti-cancer effects, and promote a major inhibition of focal adhesion kinase, actin, and protocollagen synthesis. In conclusion, coffee shows many beneficial effects, and experimental data in favor of coffee consumption in patients with liver diseases are encouraging, but further prospective studies are needed to demonstrate its preventive and therapeutic role in chronic liver diseases.

Decrease in UCP1 by sustained high lipid promotes NK cell necroptosis to exacerbate nonalcoholic liver fibrosis

Uncoupling protein 1 (UCP1) catalyzes the leak of protons across the mitochondrial inner membrane for thermogenesis. Compromised NK cell activity is involved in the occurrence of nonalcoholic liver fibrosis. Here, decreased UCP1 in NK cells was identified in patients with advanced nonalcoholic fatty liver disease. Although no obvious changes were observed in the NK cells of physiologic UCP1−/− mice (8–10 weeks old), impaired NK cell bioactivity was shown in methionine–choline-diet (MCD)-fed UCP1−/− mice and involved in the acerbation of nonalcoholic steatohepatitis (NASH) progress to liver fibrosis. Moreover, UCP1-deficient NK cells were responsible for the aggravation of liver fibrosis, as confirmed in MCD-fed UCP1flox/flox-NCR1cre mice. Acerbation of liver fibrosis was also seen in wild-type mice when their endogenous NK cells were replaced with UCP1−/− NK cells. Transcriptions of mitophagy-associated molecules in UCP1−/− NK cells were enhanced according to RNA-seq. Electron microscopic results showed mitochondrial injuries and autophagic vesicles in MCD-fed NKWT cells, PA-treated NKWT cells, or physiologic NKKO cells. However, the co-existence of UCP1 deficiency and high lipid can synergistically induce NK cell necroptosis via DRP1S616 accompanied with reduced mitophagy. Finally, The UCP1 in NK cells was downregulated when treated by sustained high PA (600 μM) via the PPARγ/ATF2 axis. Thus, persistent high-lipid treatment not only decreases UCP1 expression but also combines with reduced UCP1 to promote NK cell necroptosis, and it is involved in NASH progression to fibrosis.

Evaluation of the Efficacy of Targeted Microbiome Therapy in Non-Alcoholic Steatohepatitis Rat Model

Abstract Non-alcoholic steatohepatitis (NASH) is the clinically aggressive variant of non-alcoholic fatty liver disease. Hippo pathway dysregulation can contribute to NASH development and progression. The use of probiotics is effective in NASH management. Our aim is to investigate the efficacy of kefir Milk in NASH management via modulation of hepatic mRNA-miRNA based panel linked to NAFLD/NASH Hippo signaling and gut microbita regulated genes which was identified using bioinformatics tools. Firstly, we analyzed mRNAs (SOX11, SMAD4 and AMOTL2), and their epigenetic regulator (miR-6807) followed by validation of target effector proteins (TGFB1, IL6 and HepPar1). Molecular, biochemical, and histopathological, analyses were used to evaluate the effects of kefir on high sucrose high fat (HSHF) diet -induced NASH in rats. We found that administration of Kefir proved to prevent steatosis and development of the inflammatory component of NASH. Moreover, Kefir improved liver function and lipid panel. At the molecular level, kefir down-regulated the expression of miR 6807-5p with subsequent increase in the expression of SOX 11, AMOTL2 associated with downregulated SMAD4, resulting in reduction in the expression of the inflammatory and fibrotic markers, IL6 and TGF-β1 in the treated and prophylactic groups compared to the untreated rats. In conclusion, Kefir suppressed NASH progression and improved both fibrosis and hepatic inflammation. The produced effect was correlated with modulation of SOX11, SMAD4 and AMOTL2 mRNAs) – (miR-6807-5p) – (TGFB, IL6 and, HepPar1) expression.

Intestinal NSD2 Aggravates Nonalcoholic Steatohepatitis Through Histone Modifications.

Mounting clinical evidence suggests that a comprised intestinal barrier contributes to the progression of nonalcoholic steatohepatitis (NASH); nevertheless, the precise mechanism remains elusive. This study unveils a significant upregulation of nuclear receptor-binding SET domain protein 2 (NSD2) in the intestines of obese humans and mice subjected to a high-fat cholesterol diet (HFCD). Intestine-specific NSD2 knockout attenuated the progression of intestinal barrier impairment and NASH, whereas NSD2 overexpression exacerbated this progression. Mechanistically, NSD2 directly regulates the transcriptional activation of Ern1 by demethylating histone H3 at lysine 36 (H3K36me2), thus activating the ERN1-JNK axis to intensify intestinal barrier impairment and subsequently foster NASH progression. These findings elucidate the crucial role of NSD2-mediated H3K36me2 in intestinal barrier impairment, suggesting that targeting intestinal NSD2 can represent a novel therapeutic approach for NASH.

Obstructive Sleep Apnea Syndrome Exacerbates NASH Progression via Selective Autophagy-Mediated Eepd1 Degradation.

Obstructive sleep apnea syndrome (OSAS), characterized by chronic intermittent hypoxia (CIH), is an independent risk factor for aggravating non-alcoholic steatohepatitis (NASH). The prevailing mouse model employed in CIH research is inadequate for the comprehensive exploration of the impact of CIH on NASH development due to reduced food intake observed in CIH-exposed mice, which deviates from human responses. To address this issue, a pair-feeding investigation with CIH-exposed and normoxia-exposed mice is conducted. It is revealed that CIH exposure aggravates DNA damage, leading to hepatic fibrosis and inflammation. The analysis of genome-wide association study (GWAS) data also discloses the association between Eepd1, a DNA repair enzyme, and OSAS. Furthermore, it is revealed that CIH triggered selective autophagy, leading to the autophagic degradation of Eepd1, thereby exacerbating DNA damage in hepatocytes. Notably, Eepd1 liver-specific knockout mice exhibit aggravated hepatic DNA damage and further progression of NASH. To identify a therapeutic approach for CIH-induced NASH, a drug screening is conducted and it is found that Retigabine dihydrochloride suppresses CIH-mediated Eepd1 degradation, leading to alleviated DNA damage in hepatocytes. These findings imply that targeting CIH-mediated Eepd1 degradation can be an adjunctive approach in the treatment of NASH exacerbated by OSAS.