Activated Natural Killer Cell Promotes Nonalcoholic Steatohepatitis Through Mediating JAK/STAT Pathway

Identification of potential metabolic biomarkers and immune cell infiltration for metabolic associated steatohepatitis by bioinformatics analysis and machine learning

BACKGROUND

Metabolic associated steatohepatitis (MASH) represents a severe subtype of metabolic associated fatty liver disease (MASLD), with an increased risk of progression to cirrhosis and hepatocellular carcinoma. The nomenclature shift from nonalcoholic steatohepatitis (NASH)/nonalcoholic fatty liver disease (NAFLD) to MASH/MASLD, underscores the pivotal role of metabolic factors in disease progression. Diagnosis of MASH currently hinges on liver biopsy, a procedure whose invasive nature limits its clinical utility. This study aims to identify and validate metabolism-related genes (MRGs) markers for the non-invasive diagnosis of MASH.

METHODS

This study extracted multiple datasets from the GEO database to identify metabolism-related differentially expressed genes (MRDEGs). Protein-Protein Interaction (PPI) network and machine learning algorithms, including Least Absolute Shrinkage and Selection Operator (LASSO) regression, Support Vector Machine-Recursive Feature Elimination (SVM-RFE), and Random Forest (RF), were applied to screen for signature MRDEGs. The diagnostic performance of these MRDEGs was evaluated using the Receiver Operating Characteristic (ROC) curve and further validated using independent external datasets. Additionally, enrichment analysis was performed to uncover key driver pathways in MASH. The infiltration levels of various immune cell types were assessed using single sample Gene Set Enrichment Analysis (ssGSEA). Finally, Spearman correlation analysis confirmed the association between signature genes and immune cells.

RESULTS

We successfully identified seven signature MRDEGs, including CYP7A1, GCK, AKR1B10, HPRT1, GPD1, FADS2, and ENO3, through PPI network analysis and machine learning algorithms. The gene model displayed exceptional diagnostic performance in the training and validation cohorts, as evidenced by the area under ROC curve (AUC) exceeding 0.9. Further enrichment analysis revealed that signature MEDEGs were primarily involved in multiple biological pathways related to glucose and lipid metabolism. Immune infiltration analysis indicated a significant increase in the infiltration levels of activated CD8 T cells, gamma-delta T cells, natural killer cells, and CD56bright NK cells in patients with MASH.

CONCLUSION

This study successfully identified seven signature MRDEGs as significant diagnostic biomarkers for MASH. The findings not only offer novel strategies for non-invasive diagnosis of MASH but also highlight the substantial role of immune cell infiltration in the progression of MASH.

The microenvironment in the development of MASLD-MASH-HCC and associated therapeutic in MASH-HCC

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a series of obesity-related metabolic liver diseases, ranging from relatively benign hepatic steatosis to metabolic-associated steatohepatitis (MASH). With the changes in lifestyle, its incidence and prevalence have risen to epidemic proportions globally. In recent years, an increasing amount of evidence has indicated that the hepatic microenvironment is involved in the pathophysiological processes of MASH-induced liver fibrosis and the formation of hepatocellular carcinoma (HCC). The hepatic microenvironment is composed of various parenchymal and non-parenchymal cells, which communicate with each other through various factors. In this review, we focus on the changes in hepatocytes, cholangiocytes, liver sinusoidal endothelial cells (LSECs), hepatic stellate cells (HSCs), Kupffer cells (KC), dendritic cells (DC), neutrophils, monocytes, T and B lymphocytes, natural killer cells (NK), natural killer T cells (NKT), mucosal-associated invariant T cells (MAIT), γδT cells, and gut microbiota during the progression of MASLD. Furthermore, we discuss promising therapeutic strategies targeting the microenvironment of MASLD-MASH-HCC.

Xiaohuang Qudan decoction alleviates ANIT-induced cholestatic liver injury by inhibiting the JAK2/STAT3 pathway and regulating TH17/Treg

Xiaohuang Qudan decoction (XHQDD) is a classical traditional Chinese medicine (TCM) formula widely used in the treatment of cholestatic liver injury. Despite its widespread use, the protective mechanism of XHQDD against cholestatic liver injury remains incompletely understood. The aim of this study was to investigate whether XHQDD mediates its beneficial effects by inhibiting the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway and regulating TH17/Treg balance. To this end, the researchers used Sprague-Dawley (SD) rats and established a cholestatic liver injury model by oral administration of alpha-naphthylisothiocyanate (ANIT). The experimental group was divided into six groups: Control (CON), ANIT, ursodeoxycholic acid (UDCA), XHQDD-low dose (XHQDD-L) group, XHQDD-medium dose (XHQDD-M) group, and XHQDD-high dose (XHQDD-H) groups. Then, after 7 d of treatment, various tests were performed to verify the results. Firstly, XHQDD and its drug-containing serum were analyzed by ultra-high performance liquid chromatography-mass spectrometry/mass spectrometry (UPLC-MS/MS), and 14 blood-entry components were identified. Then, bile flow was monitored and found to be significantly reduced in the model group, which was significantly reversed in the UDCA and XHQDD groups. To further assess ANIT-induced liver injury, hematoxylin and eosin (H&E) and Sirius red staining, alongside transmission electron microscopy (TEM), were employed to observe liver tissues, revealing hepatocellular injury, cholestasis, and hepatic fibrotic changes. Serum inflammatory factors and liver injury indicators were assessed using enzyme-linked immunosorbent assay (ELISA), indicating an inflammatory state in ANIT-induced liver injury rats. The expression levels of JAK2/STAT3-related genes and proteins in liver and intestinal tissues were measured via quantitative reverse transcription polymerase chain reaction (qRT-PCR), immunohistochemistry, immunofluorescence (IF) staining, and Western blottting (WB) assays. These studies revealed that the inflammatory state of liver-injured rats was inextricably linked to the inflammatory cascade associated with the JAK2/STAT3 pathway and that XHQDD may exert anti-inflammatory efficacy by inhibiting the JAK2/STAT3 pathway. Flow cytometry was used to determine the percentage of T helper 17 (Th17)/regulatory T (Treg) cells in serum and hepatocytes, and it was further found that XHQDD was able to regulate Th17/Treg immune homeostasis in liver-injured rats. The findings suggest that XHQDD markedly alleviates inflammation in ANIT rats, potentially treating cholestasis and liver injury through JAK2/STAT3 inhibition and Th17/Treg balance regulation.

Mitigating cyclophosphamide-induced hepatorenal toxicity: Linalool's role in modulating oxidative stress, inflammation, and apoptosis

Cyclophosphamide (CP) is associated with detrimental side effect including hepatic and renal toxicities. Linalool (LIN), acyclic monoterpene alcohol, is acquired from several plants' essential oils. Rats were disseminated into four groups. Group 1: Normal and Cyclophosphamide (CP) groups in which rats were given normal saline or CP intraperitoneally (200 mg/kg, ip on 12nd). Group 3 and 4 (LIN 50 + CP and LIN 100 + CP) groups in which rats were administered LIN (50 or 100 mg/kg) orally for 14 days and CP (200 mg/kg, ip on 12nd). Assessment of hepatic and renal function tests and histopathological examination were performed. Oxidative stress indicators, inflammatory mediators, and apoptosis markers in hepatic and renal homogenates were assessed. JAK2/STAT3/NFκB gene expression was measured. The network pharmacology study suggests JAK2 as one the targets so molecular docking of LIN against JAK2 was accomplished. LIN administration with CP resulted in a significant reduction in liver function test including ALT, AST, LDL, bilirubin, and γGTT1 and in renal function markers including BUN, creatinine, uric acid, Kim-1, NGAL, and CysC. Also, LIN increases in antioxidant ability via enhancing GST, GSH-Px, GSH-R, SOD, and catalase as well as a declining NO, MDA levels. Furthermore, LIN significantly diminished JAK2/STAT3/NFκB gene expressions with subsequent reduction in the inflammatory markers including TNF-α, MPO, ICAM-1, IL-6, and IL-1β levels and the apoptotic markers Bax and cleavage caspase-3 and 9. LIN protected the hepatic and renal tissues from ROS damage and mitigated JAK2/STAT3/NFκB with subsequent anti-inflammatory and anti-apoptotic properties.

Efficacy of measuring natural killer-activating receptor ligands to predict the pathogenesis of metabolic dysfunction-associated steatotic liver disease

OBJECTIVE

The proportion of non-B/non-C hepatocellular carcinoma cases is increasing, and the principal cause is metabolic dysfunction-associated steatotic liver disease (MASLD). The degree of intrahepatic natural killer (NK) cell infiltration has been reported to correlate with MASLD progression. However, reports on MASLD are limited. We aimed to investigate the involvement of NK cell-activating receptor ligands in MASLD pathogenesis.

METHODS

This study cohort comprised 69 patients with biopsy-proven MASLD treated between 2012 and 2018 at our institute. The concentrations of major histocompatibility complex class I polypeptide-related sequences A and B (MICA and MICB, respectively) and B7H6 in patient sera were measured using enzyme-linked immunosorbent assay kits. Data were statistically compared between those with metabolic-associated steatotic liver (MASL, n = 25) and those with metabolic dysfunction-associated steatohepatitis (MASH, n = 44). The clinical characteristics related to higher concentrations of each NK cell-activating receptor ligand were also investigated.

RESULTS

The MASH group had a higher level of the ligands than the MASL group. Furthermore, the MASH group had a significantly higher level of the Mac-2-binding protein glycosylation isomer (M2BPGi) than the MASL group (p < 0.001). MICA and MICB were positively correlated, and all three ligands were strongly correlated with alpha-fetoprotein and protein induced by vitamin K absence 2. Although MICB levels positively correlated with aspartate transaminase and alanine transaminase levels (p < 0.005), patients with higher MICA and B7H6 levels had higher M2BPGi levels. Interestingly, concentrations of B7H6 were significantly correlated with portal inflammation (p < 0.001), rather than lobular inflammation.

CONCLUSION

The three NK-activating receptor ligands were higher in the sera of the MASH group than those of the MASL group and strongly correlated with tumor markers, indicating the potential for hepatocarcinogenesis. Higher concentrations of serum B7H6 were correlated with advanced fibrosis and the degree of portal inflammation, which is a potential biomarker for predicting the pathogenesis of MASH.

Pharmacological treatment for metabolic dysfunction-associated steatotic liver disease and related disorders: Current and emerging therapeutic options

Metabolic dysfunction-associated steatotic liver disease (MASLD; formerly known as nonalcoholic fatty liver disease) is a chronic liver disease affecting over a billion individuals worldwide. MASLD can gradually develop into more severe liver pathologies, including metabolic dysfunction-associated steatohepatitis (MASH), cirrhosis, and liver malignancy. Notably, although being a global health problem, there are very limited therapeutic options against MASLD and its related diseases. While a thyroid hormone receptor agonist (resmetirom) is recently approved for MASH treatment, other efforts to control these diseases remain unsatisfactory. Given the projected rise in MASLD and MASH incidence, it is urgent to develop novel and effective therapeutic strategies against these prevalent liver diseases. In this article, the pathogenic mechanisms of MASLD and MASH, including insulin resistance, dysregulated nuclear receptor signaling, and genetic risk factors (eg, patatin-like phospholipase domain-containing 3 and hydroxysteroid 17-β dehydrogenase-13), are introduced. Various therapeutic interventions against MASH are then explored, including approved medication (resmetirom), drugs that are currently in clinical trials (eg, glucagon-like peptide 1 receptor agonist, fibroblast growth factor 21 analog, and PPAR agonist), and those failed in previous trials (eg, obeticholic acid and stearoyl-CoA desaturase 1 antagonist). Moreover, given that the role of gut microbes in MASLD is increasingly acknowledged, alterations in the gut microbiota and microbial mechanisms in MASLD development are elucidated. Therapeutic approaches that target the gut microbiota (eg, dietary intervention and probiotics) against MASLD and related diseases are further explored. With better understanding of the multifaceted pathogenic mechanisms, the development of innovative therapeutics that target the root causes of MASLD and MASH is greatly facilitated. The possibility of alleviating MASH and achieving better patient outcomes is within reach. SIGNIFICANCE STATEMENT: Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease worldwide, and it can progress to more severe pathologies, including steatohepatitis, cirrhosis, and liver cancer. Better understanding of the pathogenic mechanisms of these diseases has facilitated the development of innovative therapeutic strategies. Moreover, increasing evidence has illustrated the crucial role of gut microbiota in the pathogenesis of MASLD and related diseases. It may be clinically feasible to target gut microbes to alleviate MASLD in the future.

Liver diseases: epidemiology, causes, trends and predictions

As a highly complex organ with digestive, endocrine, and immune-regulatory functions, the liver is pivotal in maintaining physiological homeostasis through its roles in metabolism, detoxification, and immune response. Various factors including viruses, alcohol, metabolites, toxins, and other pathogenic agents can compromise liver function, leading to acute or chronic injury that may progress to end-stage liver diseases. While sharing common features, liver diseases exhibit distinct pathophysiological, clinical, and therapeutic profiles. Currently, liver diseases contribute to approximately 2 million deaths globally each year, imposing significant economic and social burdens worldwide. However, there is no cure for many kinds of liver diseases, partly due to a lack of thorough understanding of the development of these liver diseases. Therefore, this review provides a comprehensive examination of the epidemiology and characteristics of liver diseases, covering a spectrum from acute and chronic conditions to end-stage manifestations. We also highlight the multifaceted mechanisms underlying the initiation and progression of liver diseases, spanning molecular and cellular levels to organ networks. Additionally, this review offers updates on innovative diagnostic techniques, current treatments, and potential therapeutic targets presently under clinical evaluation. Recent advances in understanding the pathogenesis of liver diseases hold critical implications and translational value for the development of novel therapeutic strategies.

Immunology and treatments of fatty liver disease

Alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD) are two major chronic liver diseases worldwide. The triggers for fatty liver can be derived from external sources such as adipose tissue, the gut, personal diet, and genetics, or internal sources, including immune cell responses, lipotoxicity, hepatocyte death, mitochondrial dysfunction, and extracellular vesicles. However, their pathogenesis varies to some extent. This review summarizes various immune mechanisms and therapeutic targets associated with these two types of fatty liver disease. It describes the gut-liver axis and adipose tissue-liver crosstalk, as well as the roles of different immune cells (both innate and adaptive immune cells) in fatty liver disease. Additionally, mitochondrial dysfunction, extracellular vesicles, microRNAs (miRNAs), and gastrointestinal hormones are also related to the pathogenesis of fatty liver. Understanding the pathogenesis of fatty liver and corresponding therapeutic strategies provides a new perspective for developing novel treatments for fatty liver disease.

The CCL5/CCR5 axis in ulcerative colitis

Ulcerative colitis (UC) is a chronic nonspecific inflammatory bowel disease characterized mainly by inflammatory changes in the intestinal mucosa. While the specific etiology of UC remains unclear, it is generally believed that it is related to many factors, among which the imbalance in the expression of molecules involved in pro-inflammatory and anti-inflammatory processes can lead to UC. CCL5 (C-C chemokine ligand 5) is one of the key pro-inflammatory factors and plays an indispensable role in various inflammatory diseases, including UC. CCL5 binds and activates the receptor CCR5 (C-C chemokine receptor type 5), which in turn, promotes signaling pathways such as PI3K/AKT, NF-κB, and Ras/MAPK, playing an important role in the pathogenesis of UC. The focus of this paper is on the function of the CCL5/CCR5 axis and its subsequent signaling pathways in UC therapy. In addition to this, the article further explores the possible healing benefits of CCR5 antagonists and agonists aimed at the CCL5/CCR5 axis for UC treatment.

Links between fecal microplastics and parameters related to metabolic dysfunction-associated steatotic liver disease (MASLD) in humans: An exploratory study

Microplastics (MPs) can persist in the environment and human body. Murine studies showed that exposure to MPs could cause metabolic dysregulation, contributing metabolic dysfunction-associated steatotic liver disease (MASLD) or steatohepatitis (MASH). However, research on the role of MPs in humans is limited. Thus, we aimed to assess links between human fecal MPs and liver histology, gene expression, immune cells and intestinal microbiota (IM). We included 6 lean healthy liver donors and 6 normal liver (obese) and 11 MASH patients. Overall, pre-BSx, we observed no significant differences in fecal MPs between groups. However, fecal MP fibers and total MPs positively correlated with portal and total macrophages and total killer T cells while total fecal MPs were positively correlated with natural killer cells. Additionally, 19 genes related to immune system and apoptosis correlated with fecal MPs at baseline. Fecal MP fibers correlated positively with fecal Bifidobacterium and negatively with Lachnospiraceae. Patients with MASH (n = 11) were re-assessed 12-months post-bariatric surgery (BSx) and we found that those with persistent disease (n = 4) had higher fecal MP fragments than those with normalized liver histology (n = 7). At 12-month post-BSx, MP fragments positively correlated with helper T cells and total MPs positively correlated with natural killer T cells and B cells. Our study is the first to look at 1) the role of MPs in MASH and its association with IM, immune cells and hepatic gene expression and 2) look at the role of MPs longitudinally in MASH persistence following BSx. Future research should further explore this relationship.

Active role of the immune system in metabolic dysfunction-associated steatotic liver disease

Non-alcoholic fatty liver disease, recently renamed metabolic dysfunction-associated steatotic liver disease (MASLD), is a complex multifactorial disease that progresses from steatohepatitis (MASH) to liver cirrhosis and liver cancer. Recent research has revealed that crosstalk between innate immune cells and hepatic parenchymal and non-parenchymal cells is involved in the pathogenesis of liver disease in MASLD/MASH. Of particular importance, novel inflammatory mechanisms, including macrophage diversity, neutrophil NETosis, B-cell biology, auto-reactive T cells, unconventional T cells, and dendritic cell-T cell interactions, are considered key drivers for disease progression. These mechanisms and factors are potential targets for the therapeutic intervention of MASLD/MASH. In this review, we focus on recent discoveries related to liver inflammation and discuss the role of innate immune cell subsets in MASLD/MASH.

Salidroside may target PPARα to exert preventive and therapeutic activities on NASH

Background

Salidroside (SDS), a phenylpropanoid glycoside, is an antioxidant component isolated from the traditional Chinese medicine Rhodiola rosea and has multifunctional bioactivities, particularly possessing potent hepatoprotective function. Non-alcoholic steatohepatitis (NASH) is one of the most prevalent chronic liver diseases worldwide, but it still lacks efficient drugs. This study aimed to assess the preventive and therapeutic effects of SDS on NASH and its underlying mechanisms in a mouse model subjected to a methionine- and choline-deficient (MCD) diet.

Methods

C57BL/6J mice were fed an MCD diet to induce NASH. During or after the formation of the MCD-induced NASH model, SDS (24 mg/kg/day) was supplied as a form of diet for 4 weeks. The histopathological changes were evaluated by H&E staining. Oil Red O staining and Sirius Red staining were used to quantitatively determine the lipid accumulation and collagen fibers in the liver. Serum lipid and liver enzyme levels were measured. The morphology of autophagic vesicles and autophagosomes was observed by transmission electron microscopy (TEM), and qRT-PCR and Western blotting were used to detect autophagy-related factor levels. Immunohistochemistry and TUNEL staining were used to evaluate the apoptosis of liver tissues. Flow cytometry was used to detect the composition of immune cells. ELISA was used to evaluate the expression of serum inflammatory factors. Transcript-proteome sequencing, molecular docking, qRT-PCR, and Western blotting were performed to explore the mechanism and target of SDS in NASH.

Results

The oral administration of SDS demonstrated comprehensive efficacy in NASH. SDS showed both promising preventive and therapeutic effects on NASH in vivo. SDS could upregulate autophagy, downregulate apoptosis, rebalance immunity, and alleviate inflammation to exert anti-NASH properties. Finally, the results of transcript-proteome sequencing, molecular docking evaluation, and experimental validation showed that SDS might exert its multiple effects through targeting PPARα.

Conclusion

Our findings revealed that SDS could regulate liver autophagy and apoptosis, regulating both innate immunity and adaptive immunity and alleviating inflammation in NASH prevention and therapy via the PPAR pathway, suggesting that SDS could be a potential anti-NASH drug in the future.

Role of gut microbiota and immune cells in metabolic-associated fatty liver disease: clinical impact

In 2020, a revised definition of fatty liver disease associated with metabolic dysfunction (MAFLD) was proposed to replace non-alcoholic fatty liver (NAFLD). Liver steatosis and at least one of the three metabolic risk factors, including type 2 diabetes, obesity, or signs of metabolic dysregulation, are used to diagnose MAFLD. MAFLD, similarly to NAFLD, is characterized by a spectrum of disease ranging from simple steatosis to advanced metabolic steatohepatitis with or without fibrosis, and may progress to cirrhosis and liver cancer, including increased risk of other critical extrahepatic diseases. Even though the pathophysiology of MAFLD and potential therapeutic targets have been explored in great detail, there is yet no Food and Drug Administration approved treatment. Recently, gut microbiome-derived products (e.g., endotoxins and metabolites) involved in intestinal barrier disruption, systemic inflammation, and modification of intrahepatic immunity have been associated with MAFLD development and progression. Therefore, different strategies could be adopted to modify the gut microbiome to improve outcomes in early and progressive MAFLD. Here, we provide an overview of mechanisms that may link the gut microbiome and immune response during the onset of liver steatosis and progression to steatohepatitis and fibrosis in patients with MAFLD. Finally, gut microbiota-based approaches are discussed as potential personalized treatments against MAFLD.

SGLT2 inhibitor promotes ketogenesis to improve MASH by suppressing CD8+ T cell activation

During the progression of metabolic dysfunction-associated steatohepatitis (MASH), the accumulation of auto-aggressive CD8+ T cells significantly contributes to liver injury and inflammation. Empagliflozin (EMPA), a highly selective inhibitor of sodium-glucose co-transporter 2 (SGLT2), exhibits potential therapeutic benefits for liver steatosis; however, the underlying mechanism remains incompletely elucidated. Here, we found that EMPA significantly reduced the hepatic accumulation of auto-aggressive CD8+ T cells and lowered granzyme B levels in mice with MASH. Mechanistically, EMPA increased β-hydroxybutyric acid by promoting the ketogenesis of CD8+ T cells via elevating 3-hydroxybutyrate dehydrogenase 1 (Bdh1) expression. The β-hydroxybutyric acid subsequently inhibited interferon regulatory factor 4 (Irf4), which is crucial for CD8+ T cell activation. Furthermore, the ablation of Bdh1 in T cells aggravated the manifestation of MASH and hindered the therapeutic efficacy of EMPA. Moreover, a case-control study also showed that SGLT2 inhibitor treatment repressed CD8+ T cell infiltration and improved liver injury in patients with MASH. In summary, our study indicates that SGLT2 inhibitors can target CD8+ T cells and may be an effective strategy for treating MASH.

Immune signature and therapeutic approach of natural killer cell in chronic liver disease and hepatocellular carcinoma

Natural killer (NK) cells are one of the key members of innate immunity that predominantly reside in the liver, potentiating immune responses against viral infections or malignant tumors. It has been reported that changes in cell numbers and function of NK cells are associated with the development and progression of chronic liver diseases (CLDs) including non-alcoholic fatty liver disease, alcoholic liver disease, and chronic viral hepatitis. Also, it is known that the crosstalk between NK cells and hepatic stellate cells plays an important role in liver fibrosis and cirrhosis. In particular, the impaired functions of NK cells observed in CLDs consequently contribute to occurrence and progression of hepatocellular carcinoma (HCC). Chronic infections by hepatitis B or C viruses counteract the anti-tumor immunity of the host by producing the sheddases. Soluble major histocompatibility complex class I polypeptide-related sequence A (sMICA), released from the cell surfaces by sheddases, disrupts the interaction and affects the function of NK cells. Recently, the MICA/B-NK stimulatory receptor NK group 2 member D (NKG2D) axis has been extensively studied in HCC. HCC patients with low membrane-bound MICA or high sMICA concentration have been associated with poor prognosis. Therefore, reversing the sMICA-mediated downregulation of NKG2D has been proposed as an attractive strategy to enhance both innate and adaptive immune responses against HCC. This review aims to summarize recent studies on NK cell immune signatures and its roles in CLD and hepatocellular carcinogenesis and discusses the therapeutic approaches of MICA/B-NKG2D-based or NK cell-based immunotherapy for HCC.

Threonine Deficiency Increases Triglyceride Deposition in Primary Duck Hepatocytes by Reducing STAT3 Phosphorylation

Liver lipid metabolism disruption significantly contributes to excessive fat buildup in waterfowl. Research suggests that the supplementation of Threonine (Thr) in the diet can improve liver lipid metabolism disorder, while Thr deficiency can lead to such metabolic disorders in the liver. The mechanisms through which Thr regulates lipid metabolism remain unclear. STAT3 (signal transducer and activator of transcription 3), a crucial transcription factor in the JAK-STAT (Janus kinase-signal transducer and activator of transcription) pathway, participates in various biological processes, including lipid and energy metabolism. This research investigates the potential involvement of STAT3 in the increased lipid storage seen in primary duck hepatocytes as a result of a lack of Thr. Using small interfering RNA and Stattic, a specific STAT3 phosphorylation inhibitor, we explored the impact of STAT3 expression patterns on Thr-regulated lipid synthesis metabolism in hepatocytes. Through transcriptome sequencing, we uncovered pathways related to lipid synthesis and metabolism jointly regulated by Thr and STAT3. The results showed that Thr deficiency increases lipid deposition in primary duck hepatocytes (p < 0.01). The decrease in protein and phosphorylation levels of STAT3 directly caused this deposition (p < 0.01). Transcriptomic analysis revealed that Thr deficiency and STAT3 knockdown jointly altered the mRNA expression levels of pathways related to long-chain fatty acid synthesis and energy metabolism (p < 0.05). Thr deficiency, through mediating STAT3 inactivation, upregulated ELOVL7, PPARG, MMP1, MMP13, and TIMP4 mRNA levels, and downregulated PTGS2 mRNA levels (p < 0.01). In summary, these results suggest that Thr deficiency promotes lipid synthesis, reduces lipid breakdown, and leads to lipid metabolism disorders and triglyceride deposition by downregulating STAT3 activity in primary duck hepatocytes.

Down Syndrome and Autoimmune Disease

Down syndrome is the most common genetic cause of intellectual disability and has previously been associated with a variety of autoimmune disorders affecting multiple organ systems. The high prevalence of autoimmune disease, in conjunction with other inflammatory and infectious diseases, in this population suggests an intrinsic immune dysregulation associated with triplication of chromosome 21. Emerging data on the role of chromosome 21 in interferon activation, cytokine production, and activation of B-cell mediated autoimmunity are emerging hypotheses that may explain the elevated prevalence of autoimmune thyroid disease, celiac disease, type I diabetes, autoimmune skin disease, and a variety of autoimmune neurologic conditions. As the life expectancy for individuals with Down syndrome increases, knowledge of the epidemiology, clinical features, management and underlying causes of these conditions will become increasingly important. Disorders such as Hashimoto's thyroiditis are prevalent in between 13 and 34% of individuals with Down syndrome but only 3% of the neurotypical population, a pattern similarly recognized in individuals with Celiac Disease (5.8% v 0.5-2%), alopecia areata (27.7% v. 2%), and vitiligo (4.4% v. 0.05-1.55%), respectively. Given the chronicity of autoimmune conditions, early identification and management can significantly impact the quality of life of individuals with Down syndrome. This comprehensive review will highlight common clinical autoimmune conditions observed in individuals with Down syndrome and explore our current understanding of the mechanisms of disease in this population.

An overview of the cholesterol metabolism and its proinflammatory role in the development of MASLD

Cholesterol is an essential lipid molecule in mammalian cells. It is not only involved in the formation of cell membranes but also serves as a raw material for the synthesis of bile acids, vitamin D, and steroid hormones. Additionally, it acts as a covalent modifier of proteins and plays a crucial role in numerous life processes. Generally, the metabolic processes of cholesterol absorption, synthesis, conversion, and efflux are strictly regulated. Excessive accumulation of cholesterol in the body is a risk factor for metabolic diseases such as cardiovascular disease, type 2 diabetes, and metabolic dysfunction-associated steatotic liver disease (MASLD). In this review, we first provide an overview of the discovery of cholesterol and the fundamental process of cholesterol metabolism. We then summarize the relationship between dietary cholesterol intake and the risk of developing MASLD, and also the animal models of MASLD specifically established with a cholesterol-containing diet. In the end, the role of cholesterol-induced inflammation in the initiation and development of MASLD is discussed.

Transcription Factor E2F7 Hampers the Killing Effect of NK Cells against Colorectal Cancer Cells via Activating RAD18 Transcription

As a pivotal defensive line against multitudinous malignant tumors, natural killer (NK) cells exist in the tumor microenvironment (TME). RAD18 E3 Ubiquitin Protein Ligase (RAD18) has been reported to foster the malignant progression of multiple cancers, but its effect on NK function has not been mined. Here, the study was designed to mine the mechanism by which RAD18 regulates the killing effect of NK cells on colorectal cancer (CRC) cells. Expression of E2F Transcription Factor 7 (E2F7) and RAD18 in CRC tissues, their correlation, binding sites, and RAD18 enrichment pathway were analyzed by bioinformatics. Expression of E2F7 and RAD18 in cells was assayed by qRT-PCR and western blot. Dual-luciferase assay and chromatin immunoprecipitation (ChIP) assay verified the regulatory relationship between E2F7 and RAD18. CCK-8 assay was utilized to assay cell viability, colony formation assay to detect cell proliferation, lactate dehydrogenase (LDH) test to assay NK cell cytotoxicity, ELISA to assay levels of granulocyte-macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ), and immunofluorescence to detect expression of toxic molecules perforin and granzyme B. High expression of RAD18 and E2F7 was found in CRC tissues and cells. Silencing RAD18 could hamper the proliferation of CRC cells, foster viability and cytotoxicity of NK cells, and increase the secretion of GM-CSF, TNF-α, IFN-γ as well as the expression of perforin and granzyme B. Additionally, ChIP and dual-luciferase reporter assay ascertained the binding relationship between RAD18 promoter region and E2F7. E2F7 could activate the transcription of RAD18, and silencing RAD18 reversed the inhibitory effect of E2F7 overexpression on NK cell killing. This work clarified the inhibitory effect of the E2F7/RAD18 axis on NK cell killing in CRC, and proffered a new direction for immunotherapy of CRC in targeted immune microenvironment.

Innate Immunity and MASLD

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

Macrophage colony-stimulating factor and its role in the tumor microenvironment: novel therapeutic avenues and mechanistic insights

The tumor microenvironment is a complex ecosystem where various cellular and molecular interactions shape the course of cancer progression. Macrophage colony-stimulating factor (M-CSF) plays a pivotal role in this context. This study delves into the biological properties and functions of M-CSF in regulating tumor-associated macrophages (TAMs) and its role in modulating host immune responses. Through the specific binding to its receptor colony-stimulating factor 1 receptor (CSF-1R), M-CSF orchestrates a cascade of downstream signaling pathways to modulate macrophage activation, polarization, and proliferation. Furthermore, M-CSF extends its influence to other immune cell populations, including dendritic cells. Notably, the heightened expression of M-CSF within the tumor microenvironment is often associated with dismal patient prognoses. Therefore, a comprehensive investigation into the roles of M-CSF in tumor growth advances our comprehension of tumor development mechanisms and unveils promising novel strategies and approaches for cancer treatment.

The role of N6-methyladenosine in macrophage polarization: A novel treatment strategy for non-alcoholic steatohepatitis

RNA methylation modifications, as a widespread type of modification in eukaryotic cells, especially N6-methyladenosine (m6A), are associated with many activities in organisms, including macrophage polarization and progression of non-alcoholic steatohepatitis (NASH). Macrophages in the liver are of diverse origin and complex phenotype, exhibiting different functions in development of NASH. In the review, we discuss the functions of m6A and m6A-related enzymes in macrophage polarization. Furthermore, we retrospect the role of macrophage polarization in NASH. Finally, we discuss the prospects of m6A in macrophages and NASH, and provide guidance for the treatment of NASH.

Roles of innate lymphoid cells in metabolic and alcohol-associated liver diseases

Innate lymphoid cells (ILCs) have been identified as potent regulators of inflammation, cell death and wound healing, which are the main biological processes involved in the progression of chronic liver disease. Obesity and chronic alcohol consumption are the leading contributors to chronic liver diseases in developed countries, due to inappropriate lifestyles. In particular, inflammation is a key factor in these liver abnormalities and promotes the development of more severe lesions such as fibrosis, cirrhosis and hepatocellular carcinoma. Opposite roles of ILC subsets have been described in the development of chronic liver disease, depending on the stage and aetiology of the disease. The heterogeneous family of ILCs encompasses cytotoxic natural killer cells, the cytokine-producing type 1, 2 and 3 ILCs and lymphoid tissue inducer cells. Dysfunction of these immune cells provokes uncontrolled inflammation and tissue damage, which are the basis for tumour development. In this review, we provide an overview of the recent and putative roles of ILC subsets in obesity and alcohol-associated liver diseases, which are currently the major contributors to end-stage liver complications such as fibrosis/cirrhosis and hepatocellular carcinoma.

Identification and validation of cuproptosis-related molecular clusters in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a major chronic liver disease worldwide. Cuproptosis has recently been reported as a form of cell death that appears to drive the progression of a variety of diseases. This study aimed to explore cuproptosis-related molecular clusters and construct a prediction model. The gene expression profiles were obtained from the Gene Expression Omnibus (GEO) database. The associations between molecular clusters of cuproptosis-related genes and immune cell infiltration were investigated using 50 NAFLD samples. Furthermore, cluster-specific differentially expressed genes were identified by the WGCNA algorithm. External datasets were used to verify and screen feature genes, and nomograms, calibration curves and decision curve analysis (DCA) were performed to verify the performance of the prediction model. Finally, a NAFLD-diet mouse model was constructed to further verify the predictive analysis, thus providing new insights into the prediction of NAFLD clusters and risks. The role of cuproptosis in the development of non-alcoholic fatty liver disease and immune cell infiltration was explored. Non-alcoholic fatty liver disease was divided into two cuproptosis-related molecular clusters by unsupervised clustering. Three characteristic genes (ENO3, SLC16A1 and LEPR) were selected by machine learning and external data set validation. In addition, the accuracy of the nomogram, calibration curve and decision curve analysis in predicting NAFLD clusters was also verified. Further animal and cell experiments confirmed the difference in their expression in the NAFLD mouse model and Mouse hepatocyte cell line. The present study explored the relationship between non-alcoholic fatty liver disease and cuproptosis, providing new ideas and targets for individual treatment of the disease.

Bone marrow monocytes sustain NK cell-poiesis during non-alcoholic steatohepatitis

Natural killer (NK) cells are the predominant lymphocyte population in the liver. At the onset of non-alcoholic steatohepatitis (NASH), an accumulation of activated NK cells is observed in the liver in parallel with inflammatory monocyte recruitment and an increased systemic inflammation. Using in vivo and in vitro experiments, we unveil a specific stimulation of NK cell-poiesis during NASH by medullary monocytes that trans-present interleukin-15 (IL-15) and secrete osteopontin, a biomarker for patients with NASH. This cellular dialogue leads to increased survival and maturation of NK precursors that are recruited to the liver, where they dampen the inflammatory monocyte infiltration. The increase in the production of both osteopontin and the IL-15/IL-15Rα complex by bone marrow monocytes is induced by endotoxemia. We propose a tripartite gut-liver-bone marrow axis regulating the immune population dynamics and effector functions during liver inflammation.

Prophylactic treatment with Bacteroides uniformis and Bifidobacterium bifidum counteracts hepatic NK cell immune tolerance in nonalcoholic steatohepatitis induced by high fat diet

Hepatic immunity is one of the driving forces for the development of nonalcoholic steatohepatitis (NASH), and targeting gut microbiota is believed to affect the hepatic immune constitution. Here, we aimed to investigate the hepatic immunological state in NASH, with a specific emphasis on natural killer (NK) cells. In addition, we aimed to identify the contributing species that target hepatic immunity to provide new directions and support the feasibility of immunotherapy for NASH. A possible NASH population was determined by combination of long-term severe fatty liver, metabolic disorders and increased serum CK18 to detect serum immune factors and gut microbiota. NASH was induced in mice fed a high-fat diet to verify the prophylactic effect of the functional species on the immunopathology and development of NASH. Hepatic immunologic state was examined, and the effector functions of NK cells were detected. Hepatic transcriptome, proteomic, and fecal metagenome were performed. We observed a statistical increase in serum IL-10 (p < 0.001) and non-statistical decrease in interferon-γ and IL-6 in NASH population, hinting at the possibility of immune tolerance. Fecal Bacteroides uniformis and Bifidobacterium bifidum were abundant in healthy population but depleted in NASH patients. In NASH mice, hepatic CD8+T cells, macrophages, and dendritic cells were increased (p < 0.01), and NK cells were inhibited, which were identified with decreased granzyme B (p < 0.05). Bacteroides uniformis and Bifidobacterium bifidum improved hepatic pathological and metabolic cues, increased hepatic NK cells and reduced macrophages (p < 0.05). Bacteroides uniformis also restored hepatic NK cell function, which was identified as increased CD107a (p < 0.05). Transcriptional and translational profiling revealed that the functional species might restore the function of hepatic NK cells through multiple pathways, such as reduction of inhibitory molecules in NK cells. Bacteroides uniformis and Bifidobacterium bifidum are novel prophylactics for NASH that restore the impaired function of hepatic NK cells.

Hepatocyte Deubiquitinating Enzyme OTUD5 Deficiency is a Key Aggravator for Metabolic Dysfunction-Associated Steatohepatitis by Disturbing Mitochondrial Homeostasis

BACKGROUND & AIMS

Metabolic dysfunction-associated steatohepatitis (MASH) is a common chronic liver disease worldwide. No effective pharmacologic therapies for MASH have been developed; to develop such promising drugs, the underlying mechanisms regulating MASH need to be elucidated. Here, we aimed to determine the role of ovarian tumor domain-containing protein 5 (OTUD5) in MASH progression and identify a specific mechanism.

METHODS

The expression levels of OTUD subfamily under palmitic acid/oleic acid (PAOA) stimulation were screened. OTUD5 expression was assessed in human liver tissues without steatosis, those with simple steatosis, and those with MASH. MASH models were developed in hepatocyte-specific Otud5-knockout mice that were fed high-fat high-cholesterol and high-fat high-cholesterol plus high-fructose/sucrose diet for 16 weeks.

RESULTS

The expression of OTUD5 was down-regulated in fatty liver and was negatively related to the progression of MASH. Lipid accumulation and inflammation were exacerbated by Otud5 knockdown but attenuated by Otud5 overexpression under PAOA treatment. Hepatocyte-specific Otud5 deletion markedly exacerbated steatosis, inflammation, and fibrosis in the livers of 2 MASH mouse models. We identified voltage-dependent anion channel 2 (VDAC2) as an OTUD5-interacting partner; OTUD5 cleaved the K48-linked polyubiquitin chains from VDAC2, and it inhibited subsequent proteasomal degradation. The anabolic effects of OTUD5 knockdown on PAOA-induced lipid accumulation were effectively reversed by VDAC2 overexpression in primary hepatocytes. Metabolomic results revealed that VDAC2 is required for OTUD5-mediated protection against hepatic steatosis by maintaining mitochondrial function.

CONCLUSIONS

OTUD5 may ameliorate MASH progression via VDAC2-maintained mitochondrial homeostasis. Targeting OTUD5 may be a viable MASH-treatment strategy.

Molecular mechanisms of metabolic disease-associated hepatic inflammation in non-alcoholic fatty liver disease and non-alcoholic steatohepatitis

Non-alcoholic fatty liver disease (NAFLD) is the leading chronic liver disease worldwide, with a progressive form of non-alcoholic steatohepatitis (NASH). It may progress to advanced liver diseases, including liver fibrosis, cirrhosis, and hepatocellular carcinoma. NAFLD/NASH is a comorbidity of many metabolic disorders such as obesity, insulin resistance, type 2 diabetes, cardiovascular disease, and chronic kidney disease. These metabolic diseases are often accompanied by systemic or extrahepatic inflammation, which plays an important role in the pathogenesis and treatment of NAFLD or NASH. Metabolites, such as short-chain fatty acids, impact the function, inflammation, and death of hepatocytes, the primary parenchymal cells in the liver tissue. Cholangiocytes, the epithelial cells that line the bile ducts, can differentiate into proliferative hepatocytes in chronic liver injury. In addition, hepatic non-parenchymal cells, including liver sinusoidal endothelial cells, hepatic stellate cells, and innate and adaptive immune cells, are involved in liver inflammation. Proteins such as fibroblast growth factors, acetyl-coenzyme A carboxylases, and nuclear factor erythroid 2-related factor 2 are involved in liver metabolism and inflammation, which are potential targets for NASH treatment. This review focuses on the effects of metabolic disease-induced extrahepatic inflammation, liver inflammation, and the cellular and molecular mechanisms of liver metabolism on the development and progression of NAFLD and NASH, as well as the associated treatments.

Using bioinformatics and systems biology methods to identify the mechanism of interaction between COVID-19 and nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is considered a risk factor for severe COVID-19, but the mechanism remains unknown. This study used bioinformatics to help define the relationship between these diseases. The GSE147507 (COVID-19), GSE126848 (NAFLD), and GSE63067 (NAFLD-2) datasets were screened using the Gene Expression Omnibus. Common differentially expressed genes were then identified using a Venn diagram. Gene ontology analysis and KEGG pathway enrichment were performed on the differentially expressed genes. A protein-protein interaction network was also constructed using the STRING platform, and key genes were identified using the Cytoscape plugin. GES63067 was selected for validation of the results. Analysis of ferroptosis gene expression during the development of the 2 diseases and prediction of their upstream miRNAs and lncRNAs. In addition, transcription factors (TFs) and miRNAs related to key genes were identified. Effective drugs that act on target genes were found in the DSigDB. The GSE147507 and GSE126848 datasets were crossed to obtain 28 co-regulated genes, 22 gene ontology terms, 3 KEGG pathways, and 10 key genes. NAFLD may affect COVID-19 progression through immune function and inflammatory signaling pathways. CYBB was predicted to be a differential ferroptosis gene associated with 2 diseases, and the CYBB-hsa-miR-196a/b-5p-TUG1 regulatory axis was identified. TF-gene interactions and TF-miRNA coregulatory network were constructed successfully. A total of 10 drugs, (such as Eckol, sulfinpyrazone, and phenylbutazone) were considered as target drugs for Patients with COVID-19 and NAFLD. This study identified key gene and defined molecular mechanisms associated with the progression of COVID-19 and NAFLD. COVID-19 and NAFLD progression may regulate ferroptosis through the CYBB-hsa-miR-196a/b-5p-TUG1 axis. This study provides additional drug options for the treatment of COVID-19 combined with NAFLD disease.

A high-trans fat, high-carbohydrate, high-cholesterol, high-cholate diet-induced nonalcoholic steatohepatitis mouse model and its hepatic immune response

Non-alcoholic fatty liver disease (NAFLD) is a chronic progressive disease that can progress to non-alcoholic steatohepatitis (NASH). Animal models are important tools for basic NASH research. Immune activation plays a key role in liver inflammation in patients with NASH. We established a high-trans fat, high-carbohydrate, and high-cholesterol, high-cholate diet-induced (HFHCCC) mouse model. C57BL/6 mice were fed a normal or HFHCCC diet for 24 weeks, and the immune response characteristics of this model were evaluated. The proportion of immune cells in mouse liver tissues was detected by immunohistochemistry and flow cytometry, Multiplex bead immunoassay and Luminex technology was used to detecte the expression of cytokines in mouse liver tissues. The results showed that mice treated with HFHCCC diet exhibited remarkably increased hepatic triglycerides (TG) content, and the increase in plasma transaminases resulted in hepatocyte injury. Biochemical results showed that HFHCCC induced elevated hepatic lipids, blood glucose, insulin; marked hepatocyte steatosis, ballooning, inflammation, and fibrosis. The proportion of innate immunity-related cells, including Kupffer cells (KCs), neutrophils, dendritic cells (DCs), natural killer T cells (NKT), and adaptive immunity-related CD3+ T cells increased; interleukin-1α (IL-1α), IL-1β, IL-2, IL-6, IL-9, and chemokines, including CCL2, CCL3, and macrophage colony stimulating factor (G-CSF) increased. The constructed model closely approximated the characteristics of human NASH and evaluation of its immune response signature, showed that the innate immune response was more pronounced than adaptive immunity. Its use as an experimental tool for understanding innate immune responses in NASH is recommended.

Heart failure with preserved ejection fraction and non-alcoholic fatty liver disease: new insights from bioinformatics

AIMS

Heart failure with preserved ejection fraction (HFpEF) and non-alcoholic fatty liver disease (NAFLD) are related conditions with an increasing incidence. The mechanism of their relationship remains undefined. Here, we aimed to explore the potential mechanisms, diagnostic markers, and therapeutic options for HFpEF and NAFLD.

METHODS AND RESULTS

HFpEF and NAFLD datasets were downloaded from the Gene Expression Omnibus (GEO) database. Common differentially expressed genes (DEGs) were screened for functional annotation. A protein-protein interaction network was constructed based on the STRING database, and hub genes were analysed using GeneMANIA annotation. ImmuCellAI (Immune Cell Abundance Identifier) was employed for analysis of immune infiltration. We also used validation datasets to validate the expression levels of hub genes and the correlation of immune cells. To screen for diagnostic biomarkers, we employed the least absolute shrinkage and selection operator and support vector machine-recursive feature elimination. Drug signature database was used to predict potential therapeutic drugs. Our analyses identified a total of 33 DEGs. Inflammation and immune infiltration played important roles in the development of both diseases. The data showed a close relationship between chemokine signalling pathway, cytokine-cytokine receptor interaction, calcium signalling pathway, neuroactive ligand-receptor interaction, osteoclast differentiation, and cyclic guanosine monophosphate-protein kinase G signalling pathway. We demonstrated that PRF1 (perforin 1) and IL2RB (interleukin-2 receptor subunit beta) proteins were perturbed by the diseases and may be the hub genes. The analysis showed that miR-375 may be a potential diagnostic marker for both diseases. Our drug prediction analysis showed that bosentan, eldecalcitol, ramipril, and probucol could be potential therapeutic options for the diseases.

CONCLUSIONS

Our findings revealed common pathogenesis, diagnostic markers, and therapeutic agents for HFpEF and NAFLD. There is need for further experimental studies to validate our findings.

Inflammatory processes involved in NASH-related hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related death worldwide. In the recent years nonalcoholic fatty liver disease (NAFLD) is becoming a growing cause of HCCs and the incidence of NAFLD-related HCCs is expected to further dramatically increase by the next decade. Chronic inflammation is regarded as the driving force of NAFLD progression and a key factor in hepatic carcinogenesis. Hepatic inflammation in NAFLD results from the persistent stimulation of innate immunity in response to hepatocellular injury and gut dysbiosis as well as by the activation of adaptive immunity. However, the relative roles of innate and adaptive immunity in the processes leading to HCC are still incompletely characterized. This is due to the complex interplay between different liver cell populations, which is also strongly influenced by gut-derived bacterial products, metabolic/nutritional signals. Furthermore, carcinogenic mechanisms in NAFLD/NASH appear to involve the activation of signals mediated by hypoxia inducible factors. This review discusses recent data regarding the contribution of different inflammatory cells to NAFLD-related HCC and their possible impact on patient response to current treatments.

The role of immune cells in modulating chronic inflammation and osteonecrosis

Osteonecrosis occurs when, under continuous stimulation by adverse factors such as glucocorticoids or alcohol, the death of local bone and marrow cells leads to abnormal osteoimmune function. This creates a chronic inflammatory microenvironment, which interferes with bone regeneration and repair. In a variety of bone tissue diseases, innate immune cells and adaptive immune cells interact with bone cells, and their effects on bone metabolic homeostasis have attracted more and more attention, thus developing into a new discipline - osteoimmunology. Immune cells are the most important regulator of inflammation, and osteoimmune disorder may be an important cause of osteonecrosis. Elucidating the chronic inflammatory microenvironment regulated by abnormal osteoimmune may help develop potential treatments for osteonecrosis. This review summarizes the inflammatory regulation of bone immunity in osteonecrosis, explains the pathophysiological mechanism of osteonecrosis from the perspective of osteoimmunology, and provides new ideas for the treatment of osteonecrosis.

NFIC1 suppresses migration and invasion of breast cancer cells through interferon-mediated Jak-STAT pathway

NFIC1, the longest isoform of NFIC, is essential for the regulation on spatiotemporal expression of drug-metabolizing genes in liver. However, the role of NFIC1 in breast cancer is not clear. Here we showed that increased expression of NFIC1 suppressed the migration and invasion of MCF-7 cells. NFIC1 overexpression increased the expression of IFNB1, IFNL1, IFNL2 and IFNL3, and the activation of interferon-mediated Jak-STAT pathway was enhanced by NFIC1 overexpression. Treatment with Jak-STAT pathway inhibitors, Filgotinib or Ruxolitinib, reversed the suppressive effects of NFIC1 overexpression on migration and invasion of MCF-7 cells. In addition, we found that MX1 and MX2, two target genes of Jak-STAT pathway, mediated the migration and invasion of MCF-7 cells. These results demonstrated that NFIC1 inhibited the migration and invasion in MCF-7 cells through interferon-mediated activation of Jak-STAT pathway, indicating that Jak-STAT pathway might be a potential therapeutic target for preventing breast cancer metastasis.

miR204 potentially promotes non-alcoholic fatty liver disease by inhibition of cpt1a in mouse hepatocytes

Non-alcoholic fatty liver disease (NAFLD) is associated with hepatic metabolism dysfunction. However, the mechanistic role of miR204 in the development of NAFLD is unknown. We investigate the functional significance of miR204 in the evolution of NAFLD. IDH2 KO mice feed a normal diet (ND) or HFD increased body weight, epididymal fat-pad weight, lipid droplet in liver, blood parameter and inflammation compared to WT mice fed a ND or HFD. Moreover, the expression of miR204 is increased in mice with IDH2 deficiency. Increased miR204 by IDH2 deficiency regulates carnitine palmitoyltransferase 1a (cpt1a) synthesis, which inhibits fatty acid β-oxidation. Inhibition of miR204 prevents the disassembly of two fatty acid-related genes by activating CPT1a expression, which decreases lipid droplet in liver, inflammatory cytokines, epididymal fat pad weight, blood parameters. Increased miR204 by IDH2 deficiency promotes the pathogenesis of HFD-induced NAFLD by regulating hepatic fatty acid metabolism and inflammation.

Vildagliptin alleviates liver fibrosis in NASH diabetic rats via modulation of insulin resistance, oxidative stress, and inflammatory cascades

AIMS

This study investigates the therapeutic potential of Vilda in a NASH model with liver fibrosis and elucidates the underlying molecular mechanisms.

MAIN METHODS

To induce NASH, male Sprague-Dawley rats were fed a high-fat diet for 24 weeks with a single dose of STZ (40 mg/kg, IP). Vilda was orally administered at two doses (10 and 20 mg/kg) for 20 weeks.

KEY FINDINGS

The induction of NASH was validated by abnormalities in hepatotoxicity indices, lipid profile, oxidative stress markers, and pathologically by marked fat deposition in hepatic tissues together with severe inflammatory cell infiltration. Moreover, NASH-affected rats demonstrated reduced insulin sensitivity manifested as elevated fasting blood glucose levels and disrupted homeostasis model assessment for insulin resistance. Vilda, at both doses, effectively abrogated all these pathological features of NASH. Mechanistically, these hepatoprotective properties of Vilda can be attributed to its antioxidant effects, anti-inflammatory effects (by inhibiting the TNF-α, NF-κB, JNK, and JAK/STAT pathways), and insulin-sensitizing effect (by upregulating the IRS-1/PI3K/Akt pathway). Besides, Vilda successfully counteracted NASH-associated liver fibrosis by downregulating the TGF-β1 pathway.

SIGNIFICANCE

The hepatoprotective and antifibrotic effects of Vilda were mostly dose-dependent. Collectively, this study offered a promising therapeutic avenue for Vilda as a novel strategy for counteracting the pathological progression of NASH and associated liver fibrosis.

Immunological risk factors for nonalcoholic fatty liver disease in patients with psoriatic arthritis: New predictive nomograms and natural killer cells

Objective

To search for the immunological risk factors of Psoriatic arthritis (PsA) combined with nonalcoholic fatty liver disease (NAFLD), development and assessment of predictive nomograms for NAFLD risk in patients with PsA, and to further explore the correlation between risk factors and dyslipidemia.

Methds

A total of 127 patients with PsA (46 with NAFLD and 81 without NAFLD) were included in this retrospective study. The clinical and serological parameters of the patients were collected. The percentage and the absolute number of lymphocytes and CD4+T cells were determined by Flow cytometry. Univariate and multivariate binary logistic regression analysis was used to screen independent risk factors of PsA complicated with NAFLD in the model population, and a nomogram prediction model was developed and assessed.

Results

(1) Univariate and multivariate logistic regression analysis of the modeling population showed that the percentage of peripheral blood T helper 1 cells (Th1%) (OR=1.12, P=0.001), body mass index (BMI) (OR=1.22, P=0.005) and triglycerides (TG) (OR=4.78, P=0.003) were independent risk factors for NAFLD in patients with PsA, which were incorporated and established a nomogram prediction model. The model has good discrimination and calibration, and also has certain clinical application value. (2) The number of peripheral blood NK cells in PsA patients was significantly positively correlated with serum triglyceride (TG) (r=0.489, P<0.001), cholesterol (CHOL) (r=0.314, P=0.003) and low-density lipoprotein (LDL) (r=0.362, P=0.001) levels.

Conclusions

Our study shows that the novel NAFLD nomogram could assess the risk of NAFLD in PsA patients with good efficiency. In addition, peripheral blood NK cell levels may be associated with dyslipidemia in patients with PsA.

Signaling Pathways Tuning Innate Lymphoid Cell Response to Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the deadliest cancers worldwide and its incidence continues to rise globally. Various causes can lead to its development such as chronic viral infections causing hepatitis, cirrhosis or nonalcoholic steatohepatitis (NASH). The contribution of immune cells to HCC development and progression has been extensively studied when it comes to adaptive lymphocytes or myeloid populations. However, the role of the innate lymphoid cells (ILCs) is still not well defined. ILCs are a family of lymphocytes comprising five subsets including circulating Natural Killer (NK) cells, ILC1s, ILC2s, ILC3s and lymphocytes tissue-inducer cells (LTi). Mostly located at epithelial surfaces, tissue-resident ILCs and NK cells can rapidly react to environmental changes to mount appropriate immune responses. Here, we provide an overview of their roles and actions in HCC with an emphasis on the importance of diverse signaling pathways (Notch, TGF-β, Wnt/β-catenin…) in the tuning of their response to HCC.