Development Of Nonalcoholic Steatohepatitis Research Articles

Nanoparticles alleviate non-alcoholic steatohepatitis via ER stress sensor-mediated intestinal barrier damage and gut dysbiosis.

The gut microbiota plays an important role in the development of non-alcoholic steatohepatitis (NASH), but the underlying mechanism is unclear. It has been found that the transcription factor XBP1s plays an important role in regulating inflammation and lipid metabolism and maintaining the integrity of intestinal barrier. However, whether XBP1s modulates the development of NASH by regulating the integrity of the intestinal barrier and altering the composition of the gut microbiota remains unknown. Mice fed with a fat-, fructose-, cholesterol-rich (FFC) diet for 24 weeks successfully established the NASH model, as demonstrated by significant hepatic steatosis, inflammation, hepatocyte injury and fibrosis. The profile of gut microbiota dynamically changed with the different stages of NAFLD via 16S rDNA sequencing the feces from mice fed with FFC diet for 0, 12, or 24 weeks or NASH mice treated with siRNA-loaded folic acid-modified TPGS (hereafter named FT@XBP1). NASH mice had significantly higher abundance of Firmicutes, Blautia and Bacteroides, and lower abundance of Bifidobacterium and GCA-900066575. FT@XBP1 supplementation had a significantly attenuated effect on FFC diet-induced weight gain, hepatic fat accumulation, dyslipidemia, inflammatory cytokines, ER stress and fibrosis. In particularly, FT@XBP1 modulates the composition of the intestinal flora; for example, NASH mice demonstrated higher abundance of Blautia and Bacteroides, and lower abundance of Actinobacteriota, Muribaculaceae and Bifidobacterium, which were partially restored by FT@XBP1 treatment. Mechanistically, FT@XBP1 increased the expression of ZO-1 in the intestine and had the potential to restore intestinal barrier integrity and improve antimicrobial defense to alleviate enterogenic endotoxemia and activation of inflammatory signaling pathways. Regulation of the key transcription factor XBP1s can partially restore the intestinal microbiota structure, maintain the integrity of intestinal mucosal barrier, and prevent the progression of NASH, providing new evidence for treating NASH.

Mice lacking cyclophilin B, but not cyclophilin A, are protected from the development of NASH in a diet and chemical-induced model.

Cyclophilins are a diverse family of peptidyl-prolyl isomerases (PPIases) of importance in a variety of essential cellular functions. We previously reported that the pan-cyclophilin inhibitor drug reconfilstat (CRV431) decreased disease in mice under the western-diet and carbon tetrachloride (CCl4) non-alcoholic steatohepatitis (NASH) model. CRV431 inhibits several cyclophilin isoforms, among which cyclophilin A (CypA) and B (CypB) are the most abundant. It is not known whether simultaneous inhibition of multiple cyclophilin family members is necessary for the observed therapeutic effects or if loss-of-function of one is sufficient. Identifying the responsible isoform(s) would enable future fine-tuning of drug treatments. Features of human liver fibrosis and complete NASH can be reliably replicated in mice by administration of intraperitoneal CCl4 alone or CCl4 in conjunction with high sugar, high cholesterol western diet, respectively. Here we show that while wild-type (WT) and Ppia-/- CypA KO mice develop severe NASH disease features under these models, Ppib-/- CypB KO mice do not, as measured by analysis of picrosirius red and hematoxylin & eosin-stained liver sections and TNFα immuno-stained liver sections. Cyclophilin inhibition is a promising and novel avenue of treatment for diet-induced NASH. In this study, mice without CypB, but not mice without CypA, were significantly protected from the development of the characteristic features of NASH. These data suggest that CypB is necessary for NASH disease progression. Further investigation is necessary to determine whether the specific role of CypB in the endoplasmic reticulum secretory pathway is of significance to its effect on NASH development.

Development of non-alcoholic steatohepatitis is associated with gut microbiota but not with oxysterol enzymes CH25H, EBI2, or CYP7B1 in mice

Liver steatosis is the most frequent liver disorder and its advanced stage, non-alcoholic steatohepatitis (NASH), will soon become the main reason for liver fibrosis and cirrhosis. The “multiple hits hypothesis” suggests that progression from simple steatosis to NASH is triggered by multiple factors including the gut microbiota composition. The Epstein Barr virus induced gene 2 (EBI2) is a receptor for the oxysterol 7a, 25-dihydroxycholesterol synthesized by the enzymes CH25H and CYP7B1. EBI2 and its ligand control activation of immune cells in secondary lymphoid organs and the gut. Here we show a concurrent study of the microbial dysregulation and perturbation of the EBI2 axis in a mice model of NASH.We used mice with wildtype, or littermates with CH25H−/−, EBI2−/−, or CYP7B1−/− genotypes fed with a high-fat diet (HFD) containing high amounts of fat, cholesterol, and fructose for 20 weeks to induce liver steatosis and NASH. Fecal and small intestinal microbiota samples were collected, and microbiota signatures were compared according to genotype and NASH disease state.We found pronounced differences in microbiota composition of mice with HFD developing NASH compared to mice did not developing NASH. In mice with NASH, we identified significantly increased 33 taxa mainly belonging to the Clostridiales order and/ or the family, and significantly decreased 17 taxa. Using an Elastic Net algorithm, we suggest a microbiota signature that predicts NASH in animals with a HFD from the microbiota composition with moderate accuracy (area under the receiver operator characteristics curve = 0.64). In contrast, no microbiota differences regarding the studied genotypes (wildtype vs knock-out CH25H−/−, EBI2−/−, or CYP7B1−/−) were observed.In conclusion, our data confirm previous studies identifying the intestinal microbiota composition as a relevant marker for NASH pathogenesis. Further, no link of the EBI2 – oxysterol axis to the intestinal microbiota was detectable in the current study.

Lipidomic signatures discriminate subtle hepatic changes in the progression of porcine nonalcoholic steatohepatitis.

Recently, the development of nonalcoholic steatohepatitis (NASH) in common strains of pigs has been achieved using a diet high in saturated fat, fructose, cholesterol, and cholate and deficient in choline and methionine. The aim of the present work was to characterize the hepatic and plasma lipidomic changes that accompany the progression of NASH and its reversal by switching pigs back to a chow diet. One month of this extreme steatotic diet was sufficient to induce porcine NASH. The lipidomic platform using liquid chromatography-mass spectrometry analyzed 467 lipid species. Seven hepatic phospholipids [PC(30:0), PC(32:0), PC(33:0), PC(33:1), PC(34:0), PC(34:3) and PC(36:2)] significantly discriminated the time of dietary exposure, and PC(30:0), PC(33:0), PC(33:1) and PC(34:0) showed rapid adaptation in the reversion period. Three transcripts (CS, MAT1A, and SPP1) showed significant changes associated with hepatic triglycerides and PC(33:0). Plasma lipidomics revealed that these species [FA 16:0, FA 18:0, LPC(17:1), PA(40:5), PC(37:1), TG(45:0), TG(47:2) and TG(51:0)] were able to discriminate the time of dietary exposure. Among them, FA 16:0, FA 18:0, LPC(17:1) and PA(40:5) changed the trend in the reversion phase. Plasma LDL-cholesterol and IL12P40 were good parameters to study the progression of NASH, but their capacity was surpassed by hepatic [PC(33:0), PC(33:1), and PC(34:0)] or plasma lipid [FA 16:0, FA 18:0, and LPC(17:1)] species. Taken together, these lipid species can be used as biomarkers of metabolic changes in the progression and regression of NASH in this model. The lipid changes suggest that the development of NASH also affects peripheral lipid metabolism.NEW & NOTEWORTHY A NASH stage was obtained in crossbred pigs. Hepatic [PC(33:0), PC(33:1) and PC(34:0)] or plasma [FA 16:0, FA 18:0 and LPC(17:1)] species were sensitive parameters to detect subtle changes in development and regression of nonalcoholic steatohepatitis (NASH). These findings may delineate the liquid biopsy to detect subtle changes in progression or in treatments. Furthermore, phospholipid changes according to the insult-inducing NASH may play an important role in accepting or rejecting fatty livers in transplantation.

Sonic hedgehog-heat shock protein 90β axis promotes the development of nonalcoholic steatohepatitis in mice

Sonic hedgehog (SHH) and heat shock protein 90β (HSP90β) have been implicated in nonalcoholic steatohepatitis (NASH) but their molecular mechanisms of action remain elusive. We find that HSP90β is a key SHH downstream molecule for promoting NASH process. In hepatocytes, SHH reduces HSP90β ubiquitylation through deubiquitylase USP31, thus preventing HSP90β degradation and promoting hepatic lipid synthesis. HSP90β significantly increases in NASH mouse model, leading to secretion of exosomes enriched with miR-28-5p. miR-28-5p directly targetes and decreases Rap1b levels, which in turn promotes NF-κB transcriptional activity in macrophages and stimulates the expression of inflammatory factors. Genetic deletion, pharmacological inhibition of the SHH-HSP90β axis, or delivery of miR-28-5p to macrophages in the male mice liver, impairs NASH symptomatic development. Importantly, there is a markedly higher abundance of miR-28-5p in NASH patient sera. Taken together, the SHH-HSP90β-miR-28-5p axis offers promising therapeutic targets against NASH, and serum miR-28-5p may serve as a NASH diagnostic biomarker.

Identification of pyroptosis-related gene signature in nonalcoholic steatohepatitis

Non-alcoholic fatty liver disease (NAFLD) has emerged as one of the major causes of liver-related morbidity and mortality globally. It ranges from simple steatosis to non-alcoholic steatohepatitis (NASH) characterized by ballooning and hepatic inflammation. In the past few years, pyroptosis has been shown as a type of programmed cell death that triggers inflammation and plays a role in the development of NASH. However, the roles of pyroptosis-related genes (PRGs) in NASH remained unclear. In this study, we studied the expression level of pyroptosis-related genes (PRGs) in NASH and healthy controls, developed a diagnostic model of NASH based on PRGs and explored the pathological mechanisms associated with pyroptosis. We further compared immune status between NASH and healthy controls, analyzed immune status in different subtypes of NASH. We identified altogether twenty PRGs that were differentially expressed between NASH and normal liver tissues. Then, a novel diagnostic model consisting of seven PRGs including CASP3, ELANE, GZMA, CASP4, CASP9, IL6 and TP63 for NASH was constructed with an area under the ROC curve (AUC) of 0.978 (CI 0.965–0.99). Obvious variations in immune status between healthy controls and NASH cases were detected. Subsequently, the consensus clustering method based on differentially expressed PRGs was constructed to divide all NASH cases into two distinct pyroptosis subtypes with different immune and biological characteristics. Pyroptosis-related genes may play an important role in NASH and can provide new insights into the diagnosis and underlying mechanisms of NASH.

Dietary intervention reverses molecular markers of hepatocellular senescence in the GAN diet-induced obese and biopsy-confirmed mouse model of NASH.

Hepatocellular senescence may be a causal factor in the development and progression of non-alcoholic steatohepatitis (NASH). The most effective currently available treatment for NASH is lifestyle intervention, including dietary modification. This study aimed to evaluate the effects of dietary intervention on hallmarks of NASH and molecular signatures of hepatocellular senescence in the Gubra-Amylin NASH (GAN) diet-induced obese (DIO) and biopsy-confirmed mouse model of NASH. GAN DIO-NASH mice with liver biopsy-confirmed NASH and fibrosis received dietary intervention by switching to chow feeding (chow reversal) for 8, 16 or 24 weeks. Untreated GAN DIO-NASH mice and chow-fed C57BL/6J mice served as controls. Pre-to-post liver biopsy histology was performed for within-subject evaluation of NAFLD Activity Score and fibrosis stage. Terminal endpoints included blood/liver biochemistry, quantitative liver histology, mitochondrial respiration and RNA sequencing. Chow-reversal promoted substantial benefits on metabolic outcomes and liver histology, as demonstrated by robust weight loss, complete resolution of hepatomegaly, hypercholesterolemia, elevated transaminase levels and hepatic steatosis in addition to attenuation of inflammatory markers. Notably, all DIO-NASH mice demonstrated ≥ 2 point significant improvement in NAFLD Activity Score following dietary intervention. While not improving fibrosis stage, chow-reversal reduced quantitative fibrosis markers (PSR, collagen 1a1, α-SMA), concurrent with improved liver mitochondrial respiration, complete reversal of p21 overexpression, lowered γ-H2AX levels and widespread suppression of gene expression markers of hepatocellular senescence. Dietary intervention (chow reversal) substantially improves metabolic, biochemical and histological hallmarks of NASH and fibrosis in GAN DIO-NASH mice. These benefits were reflected by progressive clearance of senescent hepatocellular cells, making the model suitable for profiling potential senotherapeutics in preclinical drug discovery for NASH.

Pharmacological Approaches to Nonalcoholic Fatty Liver Disease: Current and Future Therapies.

Nonalcoholic fatty liver disease (NAFLD) and its more severe form, nonalcoholic steatohepatitis (NASH), can promote the development of cirrhosis, hepatocellular carcinoma, cardiovascular disease, and type 2 diabetes. Similarly, type 2 diabetes confers the greatest risk for the development of NASH, especially when associated with obesity. Although lifestyle changes are critical to success, early implementation of pharmacological treatments for obesity and type 2 diabetes are essential to treat NASH and avoid disease progression. This article reviews current guidance regarding the use of pharmacological agents such as pioglitazone, glucagon-like peptide 1 receptor agonists, and sodium-glucose cotransporter 2 inhibitors in the setting of NAFLD and NASH. It also reviews the latest information on new drugs currently being investigated for the treatment of NASH.

Sesamin ameliorates nonalcoholic steatohepatitis through inhibiting hepatocyte pyroptosis in vivo and in vitro.

Sesamin (Ses) is a natural lignan abundantly present in sesame and sesame oil. Pyroptosis, a newly identified type of pro-inflammatory programmed necrosis, contributes to the development of non-alcoholic steatohepatitis (NASH) when hepatocyte pyroptosis is excessive. In this study, Ses treatment demonstrated an improvement in hepatic damage in mice with high-fat, high-cholesterol diet-induced NASH and palmitate (PA)-treated mouse primary hepatocytes. Notably, we discovered, for the first time, that Ses could alleviate hepatocyte pyroptosis both in vivo and in vitro. Furthermore, treatment with phorbol myristate acetate, a protein kinase Cδ (PKCδ) agonist, increased PKCδ phosphorylation and attenuated the protective effects of Ses against pyroptosis in PA-treated mouse primary hepatocytes. Mechanistically, Ses treatment alleviated hepatocyte pyroptosis in NASH, which was associated with the regulation of the PKCδ/nod-like receptor family CARD domain-containing protein 4/caspase-1 axis. This study introduces a novel concept and target, suggesting the potential use of functional factors in food to alleviate liver damage caused by NASH.

Panaxydol extracted from Panax ginseng inhibits NLRP3 inflammasome activation to ameliorate NASH-induced liver injury

Activation of NOD-like receptor protein 3 (NLRP3) inflammasome exacerbates liver inflammation and fibrosis in nonalcoholic steatohepatitis (NASH), suggesting that development of inflammasome inhibitor can become leading candidate to ameliorate NASH. Panax ginseng (P. ginseng) contains numerous bioactive natural components to reduce inflammation. This study aims to identify inhibitory components of P. ginseng for NLRP3 inflammasome activation. We separated polar and non-polar fractions of P. ginseng and tested modulation of NLRP3 inflammasome, and then identified pure component for inflammasome inhibitor which ameliorates diet-induced NASH. Non-polar P. ginseng fractions obtained from ethyl acetate solvent attenuated IL-1β secretion and expression of active caspase-1. We revealed that panaxydol (PND) is pure component to inhibit NLRP3 inflammasome activation. PND blocked inflammasome cytokines release, pyroptotic cell death, caspase-1 activation and specking of inflammasome complex. Inhibitory effect of PND was specific to NLRP3-dependent pathway via potential interaction with ATP binding motif of NLRP3. Moreover, in vivo studies showed that PND plays beneficial roles to reduce tissue inflammations through disruption of NLRP3 inflammasome and to ameliorate the development of NASH. These results provide new insight of natural products, panaxydol, for NLRP3 inflammasome inhibitor and could offer potential therapeutic candidate for reliving NASH.

Gut Microbiota Plays Essential Roles in Soyasaponin's Preventive Bioactivities against Steatohepatitis in the Methionine and Choline Deficient (MCD) Diet-Induced Non-Alcoholic Steatohepatitis (NASH) Mice.

Gut microbiota (GM) is involved in nonalcoholic steatohepatitis (NASH) development. Phytochemicals soyasaponins can prevent NASH possibly by modulating GM. This study aims to investigate the preventive bioactivities of soyasaponin monomers (SS-A1 and SS-Bb) against NASH and explores the mechanisms by targeting GM. Male C57BL/6 mice are fed with methionine and choline deficient (MCD) diet containing SS-A1 , SS-Bb, or not for 16 weeks. Antibiotics-treated pseudo germ-free (PGF) mice are fed with MCD diet containing SS-A1 , SS-Bb, or not for 8 weeks. GM is determined by 16S rRNA amplicon sequencing. Bile acids (BAs) are measured by UPLC-MS/MS. In NASH mice, SS-A1 and SS-Bb alleviate steatohepatitis and fibrosis, reduce ALT, AST, and LPS in serum, decrease TNF-α, IL-6, α-SMA, triglycerides, and cholesterol in liver. SS-A1 and SS-Bb decrease Firmicutes, Erysipelotrichaceae, unidentified-Clostridiales, Eggerthellaceae, Atopobiaceae, Aerococcus, Jeotgalicoccus, Gemella, Rikenella, increase Proteobacteria, Verrucomicrobia, Akkermansiaceae, Romboutsia, and Roseburia. SS-A1 and SS-Bb alter BAs composition in liver, serum, and feces, activate farnesoid X receptor (FXR) in liver and ileum, increase occludin and ZO-1 in intestine. However, GM clearance abrogates the preventive bioactivities of SS-A1 and SS-Bb against NASH. GM plays essential roles in soyasaponin's preventive bioactivities against steatohepatitis in MCD diet-induced NASH mice.

Mechanisms of 5-HT receptor antagonists in the regulation of fibrosis in a 3D human liver spheroid model

Non-alcoholic steatohepatitis (NASH) is a major health problem leading to liver fibrosis and hepatocellular carcinoma, among other diseases, and for which there is still no approved drug treatment. Previous studies in animal models and in LX-2 cells have indicated a role for serotonin (5-HT) and 5-HT receptors in stellate cell activation and the development of NASH. In the current study, we investigated the extent to which these findings are applicable to a human NASH in vitro model consisting of human liver spheroids containing hepatocytes and non-parenchymal cells. Treatment of the spheroids with 5-HT or free fatty acids (FFA) induced fibrosis, whereas treatment of the spheroids with the 5-HT receptor antagonists ketanserin, pimavanserin, sarpogrelate, and SB269970 inhibited FFA-induced fibrosis via a reduction in stellate cell activation as determined by the expression of vimentin, TGF-β1 and COL1A1 production. siRNA-based silencing of 5-HT2A receptor expression reduced the anti-fibrotic properties of ketanserin, suggesting a role for 5-HT receptors in general and 5-HT2A receptors in particular in the FFA-mediated increase in fibrosis in the human liver spheroid model. The results suggest a contribution of the 5-HT receptors in the development of FFA-induced human liver fibrosis with implications for further efforts in drug development.

Mic19 depletion impairs endoplasmic reticulum-mitochondrial contacts and mitochondrial lipid metabolism and triggers liver disease

Endoplasmic reticulum (ER)-mitochondria contacts are critical for the regulation of lipid transport, synthesis, and metabolism. However, the molecular mechanism and physiological function of endoplasmic reticulum-mitochondrial contacts remain unclear. Here, we show that Mic19, a key subunit of MICOS (mitochondrial contact site and cristae organizing system) complex, regulates ER-mitochondria contacts by the EMC2-SLC25A46-Mic19 axis. Mic19 liver specific knockout (LKO) leads to the reduction of ER-mitochondrial contacts, mitochondrial lipid metabolism disorder, disorganization of mitochondrial cristae and mitochondrial unfolded protein stress response in mouse hepatocytes, impairing liver mitochondrial fatty acid β-oxidation and lipid metabolism, which may spontaneously trigger nonalcoholic steatohepatitis (NASH) and liver fibrosis in mice. Whereas, the re-expression of Mic19 in Mic19 LKO hepatocytes blocks the development of liver disease in mice. In addition, Mic19 overexpression suppresses MCD-induced fatty liver disease. Thus, our findings uncover the EMC2-SLC25A46-Mic19 axis as a pathway regulating ER-mitochondria contacts, and reveal that impairment of ER-mitochondria contacts may be a mechanism associated with the development of NASH and liver fibrosis.

Group IVA Phospholipase A2 in Collagen-Producing Cells Promotes High-Fat Diet-Induced Infiltration of Inflammatory Cells into the Liver by Upregulating the Expression of MCP-1.

Nonalcoholic steatohepatitis (NASH) is characterized by hepatic inflammation and fibrosis due to excessive fat accumulation. Monocyte chemoattractant protein-1 (MCP-1) is a key chemokine that infiltrates inflammatory cells into the liver during the development of NASH. Our previous studies demonstrated that a systemic deficiency of group IVA phospholipase A2 (IVA-PLA2), an enzyme that contributes to the production of lipid inflammatory mediators, protects mice against high-fat diet-induced hepatic fibrosis and markedly suppresses the CCl4-induced expression of MCP-1 in the liver. However, it remains unclear which cell types harboring IVA-PLA2 are involved in the elevated production of MCP-1. Hence, the present study assessed the types of cells responsible for IVA-PLA2-mediated production of MCP-1 using cultured hepatic stellate cells, endothelial cells, macrophages, and hepatocytes, as well as cell-type specific IVA-PLA2 deficient mice fed a high-fat diet. A relatively specific inhibitor of IVA-PLA2 markedly suppressed the expression of MCP-1 mRNA in cultured hepatic stellate cells, but the suppression of MCP-1 expression was partial in endothelial cells and not observed in monocytes/macrophages or hepatocytes. In contrast, a deficiency of IVA-PLA2 in collagen-producing cells (hepatic stellate cells), but not in other types of cells, reduced the high-fat diet-induced expression of MCP-1 and inflammatory cell infiltration in the liver. Our results suggest that IVA-PLA2 in hepatic stellate cells is critical for hepatic inflammation in the high-fat diet-induced development of NASH. This supports a potential therapeutic approach for NASH using a IVA-PLA2 inhibitor targeting hepatic stellate cells.

Oleuropein ameliorates hyperlipidemia, oxidative stress, inflammatory and liver dysfunction biomarkers, in streptozotocin-induced diabetic rats

Diabetes mellitus (DM) is a serious threat factor for chronic liver disorders and the development of nonalcoholic steatohepatitis into cirrhosis. However, numerous pharmacological actions of olive polyphenol have been discovered, with oleuropein being a primary phenolic substance found in olive leaves, olive oil, and olive fruit (Olea europaea). Our goal is to identify the impacts of oleuropein on lipid measurements, oxidative stress, serum leptin, adiponectin levels, inflammatory status, and hepatic dysfunctions in a male rat model with streptozotocin (STZ)-induced DM. Oleuropein was orally administered to diabetic rats at a 5 mg/kg bw/day dose for 15 days. Diabetic rats treated with oleuropein demonstrated improved hepatic function test results (ALT, AST, alkaline phosphatase, and bilirubin), while activity of the low liver glucose-6-phosphate dehydrogenase (G6PDH) increased. Moreover, serum triacylglycerol, very low-density lipoprotein, low-density lipoprotein, and total cholesterol (TC) were considerably reduced, while high-density lipoprotein increased markedly. In addition, serum antioxidative enzymes such as glutathione peroxidase, catalase, glutathione-S-transferase, and superoxide dismutase increased, as well as glutathione levels. Lipid peroxidation levels were lower than those in the STZ control group. Treating diabetic rats with oleuropein not only resulted in decreased serum leptin and increased adiponectin levels but also had a substantial inhibitory effect on the elevated COX-2 and TNF-α mRNA expression levels in the livers of the STZ group. In conclusion, oleuropein has shown promising results in mitigating hyperlipidemia, oxidative stress, inflammation, and hepatic dysfunction biomarkers in diabetic rats.

Identification of key genes and functional enrichment analysis of liver fibrosis in nonalcoholic fatty liver disease through weighted gene co-expression network analysis.

Nonalcoholic fatty liver disease (NAFLD) is a common type of chronic liver disease, with severity levels ranging from nonalcoholic fatty liver to nonalcoholic steatohepatitis (NASH). The extent of liver fibrosis indicates the severity of NASH and the risk of liver cancer. However, the mechanism underlying NASH development, which is important for early screening and intervention, remains unclear. Weighted gene co-expression network analysis (WGCNA) is a useful method for identifying hub genes and screening specific targets for diseases. In this study, we utilized an mRNA dataset of the liver tissues of patients with NASH and conducted WGCNA for various stages of liver fibrosis. Subsequently, we employed two additional mRNA datasets for validation purposes. Gene set enrichment analysis (GSEA) was conducted to analyze gene function enrichment. Through WGCNA and subsequent analyses, complemented by validation using two additional datasets, we identified five genes (BICC1, C7, EFEMP1, LUM, and STMN2) as hub genes. GSEA analysis indicated that gene sets associated with liver metabolism and cholesterol homeostasis were uniformly downregulated. BICC1, C7, EFEMP1, LUM, and STMN2 were identified as hub genes of NASH, and were all related to liver metabolism, NAFLD, NASH, and related diseases. These hub genes might serve as potential targets for the early screening and treatment of NASH.

An Update on the Etiopathogenesis of NAFLD including Organokines for Early Diagnosis and Improvement of Management and Preventing Early HCC Development: A Narrative Review

Background Earlier, we reviewed different methods of treating non-alcoholic fatty acid liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH), concentrated on organokines liberated by adipose tissue (AT) and liver (adipoklines and hepatokines), adipokines in obesity with heart failure (HF), and myokines like irisin in exercise in obesity, and thought they might work as diagnostic and therapeutic targets in NAFLD and NASH with hepatocellular carcinoma (HCC). These are believed to be biological markers that can anticipate the robustness of NAFLD from NAFLD to HCC. Methods We conducted a narrative review utilizing search engines PubMed, Google Scholar; Web of Science; Embasee; Cochrane Library utilizing the MeSH terms “NAFLD”; “NASH”; “Organokines”; “Adipokines”; “Hepatokines”; “Myokines”; “Osteokines”; “Stellakines”; “Fructose”; “Gut Microbiota”; “Insulin resistance (IR)”; “Crosstalk of organokines”; “Obesity”; “T2D” from last 10-years till date in 2023. Results We found a total of 750 articles, out of which we selected 95 for this review. No meta-analysis has been done. Conclusion As acknowledged earlier, NAFLD possesses the characteristics of simple steatosis, while NASH progresses to hepatic steatosis, lobular inflammation, and an escalated diameter of hepatocytes (ballooning of hepatocytes) with or without fibrosis in 20% of cases of NAFLD. Usually, it is correlated with metabolic diseases like obesity, type 2 diabetes mellitus (T2DM), and metabolic syndrome (MetS); hence, the liberation of organokines gets manipulated in a way that might aid in the etiopathogenesis or propagation of disease. We observed that insulin resistance (IR), oxidative stress (OS), mitochondrial impairment, fructose, and gut microbiota reflected factors taking part in the development and propagation of NASH. Alterations in various organokines (inclusive of adipokines, hepatokines, myokines, osteokines, and a newer one, stellakines) produced by hepatic stellate cells (HSCs) were further seen to directly or indirectly aid in the exacerbation and propagation of disease or cause dysfunctional homeostasis. Moreover, we discuss the role of stellakines in detail, and targeting silymarin might give us an efficacious drug for the early treatment of NAFLD or NASH.

RISKY BEHAVIORS WITH NONALCOHOLIC FATTY LIVER (NAFLD) AND NONALCOHOLIC STEATOHEPATITIS (NASH) AMONG OLDER ADULTS

Abstract Background Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are emerging public health concerns among older adults, particularly those with risk behaviors. Objectives We evaluate the association between risk behavior and the prevalence of NAFLD and NASH in older adults. Methods A total of 1444 US individuals aged 60 years and older were included from the 2017- 2020 NHANES survey. Dietary, Sugar-sweetened beverages, smoking, physical activities, stiffness, controlled attenuation parameters, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were measured. We performed multivariable logistic regression models with interaction terms and stratified analysis to assess the interplay effect between soda intake and body mass index (BMI) on liver stiffness measurements. All statistical analyses were under survey modules with an appropriate sampling weight. Results The prevalence of NAFLD/NASH varied significantly by age, gender, race, alcohol use, BMI, total energy consumption, ALT, and (all p≤0.001). The results showed that several risk behaviors, including smoking, physical inactivity, and sweetened beverage consumption, were not significantly associated with developing and worsening NAFLD and NASH among elderly individuals. However, higher total energy consumption, obesity, and alcohol use were risk factors for NAFLD/NASH. Conclusion Our study findings highlight the importance of promoting some healthy lifestyle behaviors among elderly individuals to prevent the development and progression of NAFLD and NASH. Further research is needed to investigate optimal strategies for promoting healthy beh

NPC1L1 Plays a Novel Role in Nonalcoholic Fatty Liver Disease.

Niemann-Pick C1-Like 1 (NPC1L1) is a key protein in the transport of cholesterol, which exists in the brush marginal membrane of the intestinal epithelial cells and the timid duct membrane of the liver. It affects cholesterol absorption and plasma low-density lipoprotein levels. Cholesterol is both an important component of the cell membrane and a precursor of bile acid and steroid hormone synthesis. Abnormal cholesterol metabolism is closely related to nonalcoholic steatohepatitis (NASH). NASH can progress to fibrosis and cirrhosis, with serious consequences. NPC1L1 is involved in the regulation of cholesterol and lipid metabolism and plays an important role in maintaining the balance of cholesterol metabolism in the body. It also plays an important role in some metabolic diseases such as nonalcoholic fatty liver disease, obesity, and hypercholesterolemia. Therefore, it is necessary to elucidate the molecular pathological mechanism of NPC1L1 in the regulation of cholesterol metabolism and the occurrence and development of NASH, which can provide a target for the development of novel drugs for the treatment of NASH and other diseases. More importantly, it helps to accelerate the development of drugs that regulate lipid metabolism at multiple levels and reduce liver steatosis, which is extremely important for the prevention and treatment of NASH and related severe metabolic diseases.

Identification of genes regulated by lipids from seaweed Susabinori (Pyropia yezoensis) involved in the improvement of hepatic steatosis: Insights from RNA-Seq analysis in obese db/db mice

Hepatic steatosis is an early stage in the progression of non-alcoholic fatty liver disease (NAFLD) and can lead to the development of non-alcoholic steatohepatitis (NASH), a major cause of liver-related morbidity and mortality. Identification of dietary components that can alleviate hepatic steatosis is crucial for developing effective therapeutic strategies for NAFLD. Recently, we demonstrated the impact of lipids extracted from the marine red alga Susabinori (Pyropia yezoensis) in a murine model of type 2-diabete (db/db). We found that Susabinori lipids (SNL), abundant in eicosapentaenoic acid (EPA)-containing polar lipids, protected against obesity-induced hepatic steatosis in db/db mice. To understand the specific genes or biological pathways underlying the effects of SNL, we conducted RNA-Seq analysis of the hepatic transcriptome. By performing comparative analysis of differentially expressed genes between normal mice and db/db mice consuming a control diet, as well as SNL-fed db/db mice, we identified the 15 SNL-dependent up-regulated genes that were down-regulated in db/db mice but up-regulated by SNL feeding. Gene ontology and pathway analysis on these 15 genes demonstrated a significant association with the metabolisms of arachidonic acid (AA) and linoleic acid (LA). Furthermore, we observed alterations in the expression levels of monoacylglycerol lipase (Magl) and fatty acid-binding protein 4 (Fabp4) in the SNL-fed db/db mice, both of which are implicated in AA and LA metabolism. Additionally, the livers of SNL-fed db/db mice exhibited reduced levels of AA and LA, but a high accumulation of EPA. In conclusion, the SNL diet might affect the metabolisms of AA and LA, which contribute to the improvement of hepatic steatosis. Our findings provide insights into the molecular mechanisms underlying the beneficial effects of SNL.