The pro-inflammatory effects of miR-155 promote liver fibrosis and alcohol-induced steatohepatitis

Targeting TNF-α: The therapeutic potential of certolizumab pegol in the early period of cerebral ischemia reperfusion injury in mice

The neuroinflammatory response triggered by cerebral ischemia-reperfusion injury (CIRI) is characterized by the upsurge of pro-inflammatory cytokines, including TNF-α, IL-1β, and IL-6, which promote leukocyte infiltration and subsequent accumulation in the ischemic zone. This accumulation further intensifies inflammation and aggravates ischemic damage. Certolizumab pegol (CZP), a monoclonal antibody targeting TNF-α, is widely used in treating various inflammatory diseases. This study explored the therapeutic potential of CZP in a mouse model of CIRI, induced by middle cerebral artery occlusion (MCAO), focusing on its influence on the microglial inflammatory response. In vitro analyses revealed that CZP markedly inhibits TNF-α-stimulated inflammation in primary microglia with an EC50 of 1.743 ng/mL. In vivo, MCAO mice treated with CZP (10 μg/mouse, i.p.) for 3 days showed reduced infarct volume, partially improved neurological function, and diminished blood-brain barrierdisruption. Additionally, CZP treatment curtailed microglial activation and the release of pro-inflammatory mediators in the early stages of stroke. It also favorably modulated microglial M1/M2 polarization, rebalanced Th17/Treg cells dynamics, and inhibited Caspase-8-mediated GSDMD cleavage, preventing microglial pyroptosis. Collectively, this study described that the treatment with CZP reversed damaging process caused by CIRI, offering a promising therapeutic strategy for the treatment of ischemic stroke.

Dexamethasone relieves the inflammatory response caused by inguinal hernia meshes through miR-155

BACKGROUND

Inguinal hernia is a relatively common condition. Most patients with inguinal hernia require surgery. At present, mesh repair is one of the most effective methods to treat inguinal hernia, but insertion of the mesh can cause inflammation. Dexamethasone (DEX) can treat inflammation, but the mechanism by which DEX alleviates inflammation caused by inguinal hernia mesh placement remains unclear.

METHOD

We randomly divided rats into groups: negative control (NC), inguinal hernia (IH), polypropylene mesh (PM), DEX treatment, and miR-155 treatment groups. RT-qPCR was performed to determine the expression of miR-155. ELISA was implemented to determine the secretion of IL-1β, IL-6, and IL-18. Western blotting was used to detect caspase-1, JAK1, p-JAK1, STAT3, and p-STAT3 expression. A dual-luciferase reporter gene array identified a connection between miR-155 and JAK1.

RESULTS

The results revealed that the expression of miR-155, IL-1β, IL-6, and IL-18 was upregulated in the PM group. After DEX treatment, the secretion of miR-155, caspase-1, IL-1β, IL-6, and IL-18 decreased. Dual luciferase results confirmed that miR-155 induced the targeted downregulation of JAK1, while a miR-155 mimic reversed the therapeutic effect of DEX, and the expression levels of p-JAK1 and p-STAT3 increased.

CONCLUSION

DEX regulates the JAK1/STAT3 signaling pathway through miR-155 to relieve inflammation caused by inguinal hernia meshes.

Macrophage plasticity: signaling pathways, tissue repair, and regeneration

Macrophages are versatile immune cells with remarkable plasticity, enabling them to adapt to diverse tissue microenvironments and perform various functions. Traditionally categorized into classically activated (M1) and alternatively activated (M2) phenotypes, recent advances have revealed a spectrum of macrophage activation states that extend beyond this dichotomy. The complex interplay of signaling pathways, transcriptional regulators, and epigenetic modifications orchestrates macrophage polarization, allowing them to respond to various stimuli dynamically. Here, we provide a comprehensive overview of the signaling cascades governing macrophage plasticity, focusing on the roles of Toll-like receptors, signal transducer and activator of transcription proteins, nuclear receptors, and microRNAs. We also discuss the emerging concepts of macrophage metabolic reprogramming and trained immunity, contributing to their functional adaptability. Macrophage plasticity plays a pivotal role in tissue repair and regeneration, with macrophages coordinating inflammation, angiogenesis, and matrix remodeling to restore tissue homeostasis. By harnessing the potential of macrophage plasticity, novel therapeutic strategies targeting macrophage polarization could be developed for various diseases, including chronic wounds, fibrotic disorders, and inflammatory conditions. Ultimately, a deeper understanding of the molecular mechanisms underpinning macrophage plasticity will pave the way for innovative regenerative medicine and tissue engineering approaches.

M1 macrophage-derived exosomes inhibit cardiomyocyte proliferation through delivering miR-155

BACKGROUND

M1 macrophages are closely associated with cardiac injury after myocardial infarction (MI). Increasing evidence shows that exosomes play a key role in pathophysiological regulation after MI, but the role of M1 macrophage-derived exosomes (M1-Exos) in myocardial regeneration remains unclear. In this study, we explored the impact of M1 macrophage-derived exosomes on cardiomyocytes regeneration in vitro and in vivo.

METHODS

M0 macrophages were induced to differentiate into M1 macrophages with GM-CSF (50 ng/mL) and IFN-γ (20 ng/mL). Then M1-Exos were isolated and co-incubated with cardiomyocytes. Cardiomyocyte proliferation was detected by pH3 or ki67 staining. Quantitative real-time PCR (qPCR) was used to test the level of miR-155 in macrophages, macrophage-derived exosomes and exosome-treated cardiomyocytes. MI model was constructed and LV-miR-155 was injected around the infarct area, the proliferation of cardiomyocytes was counted by pH3 or ki67 staining. The downstream gene and pathway of miR-155 were predicted and verified by dual-luciferase reporter gene assay, qPCR and immunoblotting analysis. IL-6 (50 ng/mL) was added to cardiomyocytes transfected with miR-155 mimics, and the proliferation of cardiomyocytes was calculated by immunofluorescence. The protein expressions of IL-6R, p-JAK2 and p-STAT3 were detected by Western blot.

RESULTS

The results showed that M1-Exos suppressed cardiomyocytes proliferation. Meanwhile, miR-155 was highly expressed in M1-Exos and transferred to cardiomyocytes. miR-155 inhibited the proliferation of cardiomyocytes and antagonized the pro-proliferation effect of interleukin 6 (IL-6). Furthermore, miR-155 targeted gene IL-6 receptor (IL-6R) and inhibited the Janus kinase 2(JAK)/Signal transducer and activator of transcription (STAT3) signaling pathway.

CONCLUSION

M1-Exos inhibited cardiomyocyte proliferation by delivering miR-155 and inhibiting the IL-6R/JAK/STAT3 signaling pathway. This study provided new insight and potential treatment strategy for the regulation of myocardial regeneration and cardiac repair by macrophages.

Effectiveness and Safety of Different Methods of Assisted Fat Grafting: A Network Meta-Analysis

OBJECTIVE

Numerous studies have proposed the utilization of stromal vascular fraction (SVF), adipose-derived stem cells (ADSCs), and platelet products as auxiliary grafting techniques to improve the survival rate of fat grafts. This study aimed to evaluate the efficacy and safety of various fat grafting methods since 2010 through a network meta-analysis, aiming to identify the most effective technique for fat grafting.

METHODS

Clinic trials on assisted fat grafting were searched from Pubmed, Embase, Web of Science, and the Cochrane Library, spanning the period from January 1, 2010 to March 2024. The risk of bias in the included trials was meticulously assessed using the Cochrane risk of bias tool. The survival rate of fat grafts served as the primary evaluation metric for effectiveness, while complications were employed as the indicator for safety.

RESULTS

The study incorporated 31 clinic trials, involving a total of 1656 patients. The findings indicated that the survival rate with assisted fat grafting significantly surpassed that of simple fat grafting (SUCRA, 10.43%). Notably, ADSC-assisted fat grafting exhibited the highest survival rate (SUCRA, 82.17%), followed by Salvia miltiorrhiza (SM)-assisted fat grafting (SUCRA, 69.76%). In terms of safety, the most prevalent complications associated with fat grafting were fat sclerosis and fat necrosis. Adc-assisted fat grafting was correlated with the lowest incidence of complications (SUCRA, 41.00%), followed by simple fat grafting (SUCRA, 40.99%). However, PRP-assisted (SUCRA, 52.86%) and SVF-assisted fat grafting (SUCRA, 65.14%) showed higher complication rates.

CONCLUSION

Various methods of assisted fat grafting can significantly enhance the survival rate, but they often fail to effectively mitigate the incidence of complications. Compared to other methods, adipose mesenchymal stem cells-assisted fat grafting consistently yielded a higher survival rate of grafts and fewer complications. Consequently, this approach represents a relatively effective method for assisting in fat grafting at present.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

IL-37d suppresses Rheb-mTORC1 axis independently of TCS2 to alleviate alcoholic liver disease

Tuberous sclerosis complex 2 (TSC2) crucially suppresses Rheb activity to prevent mTORC1 activation. However, mutations in TSC genes lead to mTORC1 overactivation, thereby causing various developmental disorders and cancer. Therefore, the discovery of novel Rheb inhibitors is vital to prevent mTOR overactivation. Here, we reveals that the anti-inflammatory cytokine IL-37d can bind to lysosomal Rheb and suppress its activity independent of TSC2, thereby preventing mTORC1 activation. The binding of IL-37d to Rheb switch-II subregion destabilizes the Rheb-mTOR and mTOR-S6K interactions, further halting mTORC1 signaling. Unlike TSC2, IL-37d is reduced under ethanol stimulation, which results in mitigating the suppression of lysosomal Rheb-mTORC1 activity. Consequently, the recombinant human IL-37d protein (rh-IL-37d) with a TAT peptide greatly improves alcohol-induced liver disorders by hindering Rheb-mTORC1 axis overactivation in a TSC2- independent manner. Together, IL-37d emerges as a novel Rheb suppressor independent of TSC2 to terminate mTORC1 activation and improve abnormal lipid metabolism in the liver.

Roles of HIF-1α signaling in Mycobacterium tuberculosis infection: New targets for anti-TB therapeutics?

Tuberculosis (TB), a deadly infectious disease induced by Mycobacterium tuberculosis (Mtb), continues to be a global public health issue that kill millions of patents every year. Despite significant efforts have been paid to identify effective TB treatments, the emergence of drug-resistant strains of the disease and the presence of comorbidities in TB patients urges us to explore the detailed mechanisms involved in TB immunity and develop more effective innovative anti-TB strategies. HIF-1α, a protein involved in regulating cellular immune responses during TB infection, has been highlighted as a promising target for the development of novel strategies for TB treatment due to its critical roles in anti-TB host immunity. This review provides a summary of current research progress on the roles of HIF-1α in TB infection, highlighting its importance in regulating the host immune response upon Mtb infection and summarizing the influences and mechanisms of HIF-1α on anti-TB immunological responses of host cells. This review also discusses the various challenges associated with developing HIF-1α as a target for anti-TB therapies, including ensuring specificity and avoiding off-target effects on normal cell function, determining the regulation and expression of HIF-1α in TB patients, and developing drugs that can inhibit HIF-1α. More deep understanding of the molecular mechanisms involved in HIF-1α signaling, its impact on TB host status, and systematic animal testing and clinical trials may benefit the optimization of HIF-1α as a novel therapeutic target for TB.

miRNAs in patients with alcoholic liver disease: a systematic review and meta-analysis

INTRODUCTION

Alcoholic liver disease (ALD) encompasses a spectrum of liver conditions, including liver steatosis, alcoholic hepatitis (AH), fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). microRNAs (miRNAs) have garnered significant interest as potential biomarkers for ALD.

METHODS

We searched PubMed, Embase, Web of Science and Cochrane Central Register of Controlled Trials (CENTRAL) systemically from inception to June 2024. All extracted data was stratified according to the stages of ALD. The vote-counting strategy performed a meta-analysis on miRNA expression profiles.

RESULTS

We included 40 studies. In serum of individuals with alcohol-use vs. no alcohol-use, miRNA-122 and miRNA-155 were upregulated, and miRNA-146a was downregulated. In patients with ALD vs. healthy controls, miRNA-122 and miRNA-155 were also upregulated, and miRNA-146a was downregulated. However, in patients with AH vs. healthy individuals, only the serum miRNA-122 level was upregulated. Due to insufficient data on diagnostic accuracy, we failed to conclude the ability of miRNAs to distinguish between different stages of ALD-related liver fibrosis. The results for ALD-related HCC were also insufficient and controversial.

CONCLUSIONS

Circulating miRNA-122 was the most promising biomarker to manage individuals with ALD. More studies were needed for the diagnostic accuracy of miRNAs in ALD.

REGISTRATION

This protocol was registered on the International Prospective Register of Systematic Reviews (PROSPERO) (www.crd.york.ac.uk/prospero/) with registration number CRD42023391931.

NLRP3 inflammasome and its role in autoimmune diseases: A promising therapeutic target

The NOD-like receptor protein 3 (NLRP3) inflammasome is a protein complex that regulates innate immune responses by activating caspase-1 and the inflammatory cytokines IL-1β and IL-18. Numerous studies have highlighted its crucial role in the pathogenesis and development of inflammatory bowel disease, rheumatoid arthritis, systemic lupus erythematosus, autoimmune thyroid diseases, and other autoimmune diseases. Therefore, investigating the underlying mechanisms of NLRP3 in disease and targeted drug therapies holds clinical significance. This review summarizes the structure, assembly, and activation mechanisms of the NLRP3 inflammasome, focusing on its role and involvement in various autoimmune diseases. This review also identifies studies where the involvement of the NLRP3 inflammasome in the disease mechanism within the same disease appears contradictory, as well as differences in NLRP3-related gene polymorphisms among different ethnic groups. Additionally, the latest therapeutic advances in targeting the NLRP3 inflammasome for autoimmune diseases are outlined, and novel clinical perspectives are discussed. Conclusively, this review provides a consolidated source of information on the NLRP3 inflammasome and may guide future research efforts that have the potential to positively impact patient outcomes.

The role of miR-155 in urologic malignancies

MicroRNAs (miRNAs) are a class of short non-coding RNAs that play a crucial role in regulating gene expression across multiple levels. They are involved in a wide range of physiological processes, including proliferation, differentiation, apoptosis, and cell cycle control. In recent years, miRNAs have emerged as pivotal regulatory molecules in the development and progression of tumors. Among these, miR-155 has garnered significant attention due to its high expression in various diseases, particularly urologic malignancies. Since an extensive corpus of studies having focused on the roles of miR-155 in various urologic malignancies, it is essential to summarize the current evidence on this topic through a comprehensive review. Altered miR-155 expression is related to various physiological and pathological processes, including immune response, inflammation, tumor development and treatment resistance. Notably, alterations in miR-155 expression have been observed in urologic malignancies as well. The up-regulation of miR-155 expression is commonly observed in urologic malignancies, contributing to their progression by targeting specific proteins and signaling pathways. This article provides a comprehensive review of the significant role played by miR-155 in the development of urologic malignancies. Furthermore, the potential of miR-155 as a biomarker and therapeutic target in urologic malignancies is also discussed.

The role of Semaphorin 3A in oral diseases

Semaphorin 3A (SEMA3A), also referred to as H-Sema III, is a molecule with significant biological importance in regulating physiological and pathological processes. However, its role in oral diseases, particularly its association with inflammatory immunity and alveolar bone remodeling defects, remains poorly understood. This comprehensive review article aims to elucidate the recent advances in understanding SEMA3A in the oral system, encompassing nerve formation, periodontitis, pulpitis, apical periodontitis, and oral squamous cell carcinoma. Notably, we explore its novel function in inflammatory immunomodulation and alveolar bone formation during oral infectious diseases. By doing so, this review enhances our comprehension of SEMA3A's role in oral biology and opens up possibilities for modulatory approaches and potential treatments in oral diseases.

The complexity of extracellular vesicles: Bridging the gap between cellular communication and neuropathology

Brain-derived extracellular vesicles (EVs) serve a prominent role in maintaining homeostasis and contributing to pathology in health and disease. This review establishes a crucial link between physiological processes leading to EV biogenesis and their impacts on disease. EVs are involved in the clearance and transport of proteins and nucleic acids, responding to changes in cellular processes associated with neurodegeneration, including autophagic disruption, organellar dysfunction, aging, and other cell stresses. In neurodegenerative disorders (e.g., Alzheimer's disease, Parkinson's disease, etc.), EVs contribute to the spread of pathological proteins like amyloid β, tau, ɑ-synuclein, prions, and TDP-43, exacerbating neurodegeneration and accelerating disease progression. Despite evidence for both neuropathological and neuroprotective effects of EVs, the mechanistic switch between their physiological and pathological functions remains elusive, warranting further research into their involvement in neurodegenerative disease. Moreover, owing to their innate ability to traverse the blood-brain barrier and their ubiquitous nature, EVs emerge as promising candidates for novel diagnostic and therapeutic strategies. The review uniquely positions itself at the intersection of EV cell biology, neurophysiology, and neuropathology, offering insights into the diverse biological roles of EVs in health and disease.

Butyrate alleviates alcoholic liver disease-associated inflammation through macrophage regulation and polarization via the HDAC1/miR-155 axis

BACKGROUND

We recently found that butyrate could ameliorate inflammation of alcoholic liver disease (ALD) in mice. However, the exact mechanism remains incompletely comprehended. Here, we examined the role of butyrate on ALD-associated inflammation through macrophage (Mψ) regulation and polarization using in vivo and in vitro experiments.

METHODS

For in vivo experiments, C57BL/6J mice were fed modified Lieber-DeCarli liquid diets supplemented with or without ethanol and sodium butyrate (NaB). After 6 weeks of treatment, mice were euthanized and associated indicators were analyzed. For in vitro experiments, lipopolysaccharide (LPS)-induced inflammatory murine RAW264.7 cells were treated with NaB or miR-155 inhibitor/mimic to verify the anti-inflammatory effect and underlying mechanism.

RESULTS

The administration of NaB alleviated pathological damage and associated inflammation, including LPS, tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1β levels in ALD mice. NaB intervention restored the imbalance of macrophage polarization by inhibiting inducible nitric oxide synthase (iNOS) and elevating arginase-1 (Arg-1). Moreover, NaB reduced histone deacetylase-1 (HDAC1), nuclear factor kappa-B (NF-κB), NOD-like receptor thermal protein domain associated protein 3 (NLRP3), and miR-155 expression in ALD mice, but also increased peroxisome proliferator-activated receptor-γ (PPAR-γ). Thus, MiR-155 was identified as a strong regulator of ALD. To further penetrate the role of miR-155, LPS-stimulated RAW264.7 cells co-cultured with NaB were treated with the specific inhibitor or mimic. Intriguingly, miR-155 was capable of negatively regulated inflammation with NaB intervention by targeting SOCS1, SHIP1, and IRAK-M genes.

CONCLUSION

Butyrate suppresses the inflammation in mice with ALD by regulating macrophage polarization via the HDAC1/miR-155 axis, which may potentially contribute to the novel therapeutic treatment for the disease.

Islet-resident macrophage-derived miR-155 promotes β cell decompensation via targeting PDX1

Chronic inflammation is critical for the initiation and progression of type 2 diabetes mellitus via causing both insulin resistance and pancreatic β cell dysfunction. miR-155, highly expressed in macrophages, is a master regulator of chronic inflammation. Here we show that blocking a macrophage-derived exosomal miR-155 (MDE-miR-155) mitigates the insulin resistances and glucose intolerances in high-fat-diet (HFD) feeding and type-2 diabetic db/db mice. Lentivirus-based miR-155 sponge decreases the level of miR-155 in the pancreas and improves glucose-stimulated insulin secretion (GSIS) ability of β cells, thus leading to improvements of insulin sensitivities in the liver and adipose tissues. Mechanistically, miR-155 increases its expression in HFD and db/db islets and is released as exosomes by islet-resident macrophages under metabolic stressed conditions. MDE-miR-155 enters β cells and causes defects in GSIS function and insulin biosynthesis via the miR-155-PDX1 axis. Our findings offer a treatment strategy for inflammation-associated diabetes via targeting miR-155.

Histone methyltransferase Suv39h1 regulates hepatic stellate cell activation and is targetable in liver fibrosis

OBJECTIVE

Liver fibrosis is a prelude to a host of end-stage liver diseases. Hepatic stellate cells (HSCs), switching from a quiescent state to myofibroblasts, are the major source for excessive production of extracellular matrix proteins. In the present study, we investigated the role of Suv39h1, a lysine methyltransferase, in HSC-myofibroblast transition and the implication in liver fibrosis.

DESIGN

HSC-specific or myofibroblast-specific Suv39h1 deletion was achieved by crossbreeding the Suv39h1 f/f mice to the Lrat-Cre mice or the Postn-CreERT2 mice. Liver fibrosis was induced by CCl4 injection or bile duct ligation.

RESULTS

We report that Suv39h1 expression was universally upregulated during HSC-myofibroblast transition in different cell and animal models of liver fibrosis and in human cirrhotic liver tissues. Consistently, Suv39h1 knockdown blocked HSC-myofibroblast transition in vitro. HSC-specific or myofibroblast-specific deletion of Suv39h1 ameliorated liver fibrosis in mice. More importantly, Suv39h1 inhibition by a small-molecule compound chaetocin dampened HSC-myofibroblast transition in cell culture and mitigated liver fibrosis in mice. Mechanistically, Suv39h1 bound to the promoter of heme oxygenase 1 (HMOX1) and repressed HMOX1 transcription. HMOX1 depletion blunted the effects of Suv39h1 inhibition on HSC-myofibroblast transition in vitro and liver fibrosis in vivo. Transcriptomic analysis revealed that HMOX1 might contribute to HSC-myofibroblast transition by modulating retinol homeostasis. Finally, myofibroblast-specific HMOX1 overexpression attenuated liver fibrosis in both a preventive scheme and a therapeutic scheme.

CONCLUSIONS

Our data demonstrate a previously unrecognised role for Suv39h1 in liver fibrosis and offer proof-of-concept of its targetability in the intervention of cirrhosis.

The effect of STAT1, miR-99b, and MAP2K1 in alcoholic liver disease (ALD) mouse model and hepatocyte

Alcoholic liver disease (ALD) serves as the leading cause of chronic liver diseases-related morbidity and mortality, which threatens the life of millions of patients in the world. However, the molecular mechanisms underlying ALD progression remain unclear. Here, we applied microarray analysis and experimental approaches to identify miRNAs and related regulatory signaling that associated with ALD. Microarray analysis identified that the expression of miR-99b was elevated in the ALD mouse model. The AML-12 cells were treated with EtOH and the expression of miR-99b was enhanced in the cells. The expression of miR-99b was positively correlated with ALT levels in the ALD mice. The microarray analysis identified the abnormally expressed mRNAs in ALD mice and the overlap analysis was performed with based on the differently expressed mRNAs and the transcriptional factors of miR-99b, in which STAT1 was identified. The elevated expression of STAT1 was validated in ALD mice. Meanwhile, the treatment of EtOH induced the expression of STAT1 in the AML-12 cells. The expression of STAT1 was positively correlated with ALT levels in the ALD mice. The positive correlation of STAT1 and miR-99b expression was identified in bioinformatics analysis and ALD mice. The expression of miR-99b and pri-miR-99b was promoted by the overexpression of STAT1 in AML-12 cells. ChIP analysis confirmed the enrichment of STAT1 on miR-99b promoter in AML-12 cells. Next, we found that the expression of mitogen-activated protein kinase kinase 1 (MAP2K1) was negatively associated with miR-99b. The expression of MAP2K1 was downregulated in ALD mice. Consistently, the expression of MAP2K1 was reduced by the treatment of EtOH in AML-12 cells. The expression of MAP2K1 was negative correlated with ALT levels in the ALD mice. We identified the binding site of MAP2K1 and miR-99b. Meanwhile, the treatment of miR-99b mimic repressed the luciferase activity of MAP2K1 in AML-12 cells. The expression of MAP2K1 was suppressed by miR-99b in the cells. We observed that the expression of MAP2K1 was inhibited by the overexpression of STAT1 in AML-12 cells. Meanwhile, the apoptosis of AML-12 cells was induced by the treatment of EtOH, while miR-99b mimic promoted but the overexpression of MAP2K1 attenuated the effect of EtOH in the cells. In conclusion, we identified the correlation and effect of STAT1, miR-99b, and MAP2K1 in ALD mouse model and hepatocyte. STAT1, miR-99b, and MAP2K1 may serve as potential therapeutic target of ALD.

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.

Anti-miR-873-5p improves alcohol-related liver disease by enhancing hepatic deacetylation via SIRT1

Background & Aims

Current therapies for the treatment of alcohol-related liver disease (ALD) have proven largely ineffective. Patients relapse and the disease progresses even after liver transplantation. Altered epigenetic mechanisms are characteristic of alcohol metabolism given excessive acetate and NAD depletion and play an important role in liver injury. In this regard, novel therapeutic approaches based on epigenetic modulators are increasingly proposed. MicroRNAs, epigenetic modulators acting at the post-transcriptional level, appear to be promising new targets for the treatment of ALD.

Methods

MiR-873-5p levels were measured in 23 liver tissue from Patients with ALD, and GNMT levels during ALD were confirmed using expression databases (transcriptome n = 62, proteome n = 68). High-resolution proteomics and metabolomics in mice following the Gao-binge model were used to investigate miR-873-5p expression in ALD. Hepatocytes exposed to 50 mM alcohol for 12 h were used to study toxicity. The effect of anti-miR-873-5p in the treatment outcomes of ALD was investigated.

Results

The analysis of human and preclinical ALD samples revealed increased expression of miR-873-5p in the liver. Interestingly, there was an inverse correlation with NNMT, suggesting a novel mechanism for NAD depletion and aberrant acetylation during ALD progression. High-resolution proteomics and metabolomics identified miR-873-5p as a key regulator of NAD metabolism and SIRT1 deacetylase activity. Anti-miR-873-5p reduced NNMT activity, fuelled the NAD salvage pathway, restored the acetylome, and modulated the levels of NF-κB and FXR, two known SIRT1 substrates, thereby protecting the liver from apoptotic and inflammatory processes, and improving bile acid homeostasis.

Conclusions

These data indicate that targeting miR-873-5p, a repressor of GNMT previously associated with NAFLD and acetaminophen-induced liver failure. is a novel and attractive approach to treating alcohol-induced hepatoxicity.

Impact and implications

The role of miR-873-5p has not been explicitly examined in the progression of ALD, a pathology with no therapeutic options. In this study, inhibiting miR-873-5p exerted hepatoprotective effects against ALD through rescued SIRT1 activity and consequently restored bile acid homeostasis and attenuated the inflammatory response. Targeting hepatic miR-873-5p may represent a novel therapeutic approach for the treatment of ALD.

The global perspective on peroxisome proliferator-activated receptor γ (PPARγ) in ectopic fat deposition: A review

Excessive expansion of adipocytes can have unhealthy consequences as excess free fatty acids enter other tissues and cause ectopic fat deposition by resynthesizing triglycerides. This lipid accumulation in various tissues is harmful and can increase the risk of related metabolic diseases such as type II diabetes, cardiovascular disease, and insulin resistance. Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor superfamily that play a key role in energy metabolism as fatty acid metabolism sensors, and peroxisome proliferator-activated receptor γ (PPARγ) is the main subtype responsible for fat cell differentiation and adipogenesis. In this paper, we introduce the main structure and function of PPARγ and its regulatory role in the process of lipogenesis in the liver, kidney, skeletal muscle, and pancreas. This information can serve as a reference for further understanding the regulatory mechanisms and measures of the PPAR family in the process of ectopic fat deposition.

Alcohol use disorder identification test renamed Glu-Glu Test in an area of north-west of Italy: preliminary descriptive results

BACKGROUND

The first two causes of liver cirrhosis and hepatocellular carcinoma are alcoholic and dysmetabolic. In the early stages alcohol related liver disease (ALD) is silent. For this reason, more efforts should be made to identify early individuals with hazardous/harmful alcohol consumption (AC). Alcohol use disorder identification test (AUDIT) is a validated test.

METHODS

ASL3 (Ligurian Local Health Company 3) has included the AUDIT renamed Glu-Glu Test on its institutional website dedicated to citizens. The renaming was carried out to bring citizens closer to the test with greater ease, especially younger citizens. At the end of the compilation of the test, the calculator provides the citizen with his score: in relation to his possible risk band, provides him with the appropriate advice. In case of a score higher than 7, ultrasonography and elastography (2D-SWE) are proposed.

RESULTS

From December 15, 2021, to July 15, 2022, 270 asymptomatic subjects requested a medical examination autonomously, without the indication of a health worker. In 167 patients the score found hazardous AC, in 65 harmful AC and in 38 alcohol addiction. In case of hazardous AC, fibrosis grade 1-2 was evidenced in 16.7%, fibrosis grade 3 in 4.8% and fibrosis grade 4 in 3.6% of subjects. In case of harmful AC fibrosis grade 1-2 was evidenced in 37%, grade 3 in 9%, grade 4 in 6%. In this group an HCC nodule was diagnosed. In case of alcohol addiction, fibrosis grade 1-2 was evidenced in 73.6%, grade 3 in 10.5% and grade 4 in 10.5%.

CONCLUSIONS

This preliminary experience clearly tells us that it is possible to make an early diagnosis of fibrosis and HCC starting from the AC reported autonomously by citizens.

MiRNAs in Alcohol-Related Liver Diseases and Hepatocellular Carcinoma: A Step toward New Therapeutic Approaches?

Alcohol-related Liver Disease (ALD) is the primary cause of chronic liver disorders and hepatocellular carcinoma (HCC) development in developed countries and thus represents a major public health concern. Unfortunately, few therapeutic options are available for ALD and HCC, except liver transplantation or tumor resection for HCC. Deciphering the molecular mechanisms underlying the development of these diseases is therefore of major importance to identify early biomarkers and to design efficient therapeutic options. Increasing evidence indicate that epigenetic alterations play a central role in the development of ALD and HCC. Among them, microRNA importantly contribute to the development of this disease by controlling the expression of several genes involved in hepatic metabolism, inflammation, fibrosis, and carcinogenesis at the post-transcriptional level. In this review, we discuss the current knowledge about miRNAs' functions in the different stages of ALD and their role in the progression toward carcinogenesis. We highlight that each stage of ALD is associated with deregulated miRNAs involved in hepatic carcinogenesis, and thus represent HCC-priming miRNAs. By using in silico approaches, we have uncovered new miRNAs potentially involved in HCC. Finally, we discuss the therapeutic potential of targeting miRNAs for the treatment of these diseases.

Post-translational modifications of histone and non-histone proteins in epigenetic regulation and translational applications in alcohol-associated liver disease: Challenges and research opportunities

Epigenetic regulation is a process that takes place through adaptive cellular pathways influenced by environmental factors and metabolic changes to modulate gene activity with heritable phenotypic variations without altering the DNA sequences of many target genes. Epigenetic regulation can be facilitated by diverse mechanisms: many different types of post-translational modifications (PTMs) of histone and non-histone nuclear proteins, DNA methylation, altered levels of noncoding RNAs, incorporation of histone variants, nucleosomal positioning, chromatin remodeling, etc. These factors modulate chromatin structure and stability with or without the involvement of metabolic products, depending on the cellular context of target cells or environmental stimuli, such as intake of alcohol (ethanol) or Western-style high-fat diets. Alterations of epigenetics have been actively studied, since they are frequently associated with multiple disease states. Consequently, explorations of epigenetic regulation have recently shed light on the pathogenesis and progression of alcohol-associated disorders. In this review, we highlight the roles of various types of PTMs, including less-characterized modifications of nuclear histone and non-histone proteins, in the epigenetic regulation of alcohol-associated liver disease (ALD) and other disorders. We also describe challenges in characterizing specific PTMs and suggest future opportunities for basic and translational research to prevent or treat ALD and many other disease states.

The promise of small particles: extracellular vesicles as biomarkers in liver pathology

Extracellular vesicles (EVs) are nanoscopic packages that are heterogeneous and bona fide players in hepatic physiology and pathology as they are involved in intercellular communication. EVs carrying bioactive cargoes rich in lipids, proteins or nucleic acids are implicated in the onset and progression of liver diseases. Liver pathology using liver biopsy has been assessed for several intricate conditions such as viral hepatitis, alcoholic and non-alcoholic fatty liver disease, hepatic malignancies and drug-induced liver injury. The lacunae, however, lie in early diagnosis and timely treatment of the above conditions, underscoring the need for non-invasive, accurate diagnostic tools that could replace the gold standard method of tissue biopsy. In this regard, EVs have emerged as promising candidates that could serve as potential biomarkers. In the last two decades, EVs, owing to their multifaceted charm in bringing out cell-free therapeutic responses and the ability of their cargoes to be applied to novel biomarkers, have drawn the great attention of researchers with the advancement and clinical application of liquid biopsy. In this review, we recapitulate the role of EVs and provide insights into the promising role of these small packages as biomarkers in liver pathology.

Inflammatory signaling in NASH driven by hepatocyte mitochondrial dysfunctions

Liver steatosis, inflammation, and variable degrees of fibrosis are the pathological manifestations of nonalcoholic steatohepatitis (NASH), an aggressive presentation of the most prevalent chronic liver disease in the Western world known as nonalcoholic fatty liver (NAFL). Mitochondrial hepatocyte dysfunction is a primary event that triggers inflammation, affecting Kupffer and hepatic stellate cell behaviour. Here, we consider the role of impaired mitochondrial function caused by lipotoxicity during oxidative stress in hepatocytes. Dysfunction in oxidative phosphorylation and mitochondrial ROS production cause the release of damage-associated molecular patterns from dying hepatocytes, leading to activation of innate immunity and trans-differentiation of hepatic stellate cells, thereby driving fibrosis in NASH.

Past, present, and future of chemically induced hepatocarcinogenesis rodent models: Perspectives concerning classic and new cancer hallmarks

Hepatocellular carcinoma (HCC), the main primary liver cancer, accounts for 5 % of all incident cases and 8.4 % of all cancer-related deaths worldwide. HCC displays a spectrum of environmental risk factors (viral chronic infections, aflatoxin exposure, alcoholic- and nonalcoholic fatty liver diseases) that result in molecular complexity and heterogeneity, contributing to a rising epidemiological burden, poor prognosis, and non-satisfactory treatment options. The emergence of HCC (i.e., hepatocarcinogenesis) is a multistep and complex process that addresses many (epi)genetic alterations and phenotypic traits, the so-called cancer hallmarks. "Polymorphic microbiomes", "epigenetic reprogramming", "senescent cells" and "unlocking phenotypic plasticity" are trending hallmarks/enabling features in cancer biology. As the main molecular drivers of HCC are still undruggable, chemically induced in vivo models of hepatocarcinogenesis are useful tools in preclinical research. Thus, this narrative review aimed at recapitulating the basic features of chemically induced rodent models of hepatocarcinogenesis, eliciting their permanent translational value regarding the "classic" and the "new" cancer hallmarks/enabling features. We gathered state-of-art preclinical evidence on non-cirrhotic, inflammation-, alcoholic liver disease- and nonalcoholic fatty liver-associated HCC models, demonstrating that these bioassays indeed express the recently added hallmarks, as well as reflect the interplay between classical and new cancer traits. Our review demonstrated that these protocols remain valuable for translational preclinical application, as they recapitulate trending features of cancer science. Further "omics-based" approaches are warranted while multimodel investigations are encouraged in order to avoid "model-biased" responses.

Effect of Low Testosterone Levels on the Expression of Proliferator-Activated Receptor Alpha in Female Patients with Primary Biliary Cholangitis

Sex-dependent patterns in chronic immune-mediated cholangiopathies, like primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), remain poorly understood. Peroxisome proliferator-activated receptor alpha (PPAR-α), expressed in immune cells, plays a key role in innate defence. In this study, the relationship between PPAR-α expression in peripheral blood mononuclear cells (PBMCs), serum androgen levels, IFNγ production, and sex-dependent tendencies during the development of PBC and PSC was investigated. We confirmed that normal cholangiocytes respond to PPAR-α and inhibit the lipopolysaccharide-induced expression of IL-6, IL-1b, and TNFα. Compared with PSC patients, PPAR-α was downregulated, while IFNγ was upregulated, in the PBMCs of PBC patients. When the analysis was conducted on females only, there was no difference in PPAR-α, but IFNγ was elevated in females with PBC compared with those with PSC. Serum testosterone concentrations in females with PBC were below the normal range (regardless of age) and correlated positively with PPAR-α and negatively with IFNγ. While PPAR-α has been reported to be a target of miR-155 and miR-21, no correlations with these microRNAs were observed in the PBMCs. However, a positive correlation between miR-21 and IFNγ was observed. Our results showed suppressed PPAR-α expression accompanied by reduced testosterone levels in women with PBC, which should elicit interest in the role of testosterone in PBC development.

Therapeutic inhibition of miR-155 attenuates liver fibrosis via STAT3 signaling

Most chronic liver diseases progress to liver fibrosis, which, when left untreated, can lead to cirrhosis and hepatocellular carcinoma. MicroRNA (miRNA)-targeted therapeutics have become attractive approaches to treat diseases. In this study, we investigated the therapeutic effect of miR-155 inhibition in the bile duct ligation (BDL) mouse model of liver fibrosis and evaluated the role of miR-155 in chronic liver fibrosis using miR-155-deficient (miR-155 knockout [KO]) mice. We found increased hepatic miR-155 expression in patients with cirrhosis and in the BDL- and CCl4-induced mouse models of liver fibrosis. Liver fibrosis was significantly reduced in miR-155 KO mice after CCl4 administration or BDL. To assess the therapeutic potential of miR-155 inhibition, we administered an rAAV8-anti-miR-155 tough decoy in vivo that significantly reduced liver damage and fibrosis in BDL. BDL-induced protein levels of transforming growth factor β (TGF-β), p-SMAD2/3, and p-STAT3 were attenuated in anti-miR-155-treated compared with control mice. Hepatic stellate cells from miR-155 KO mice showed attenuation in activation and mesenchymal marker expression. In vitro, miR-155 gain- and loss-of-function studies revealed that miR-155 regulates activation of stellate cells partly via STAT3 signaling. Our study suggests that miR-155 is the key regulator of liver fibrosis and might be a potential therapeutic target to attenuate fibrosis progression.

Unraveling the Complex Interplay between Epigenetics and Immunity in Alcohol-Associated Liver Disease: A Comprehensive Review

The mechanisms of immune dysfunction in alcohol-associated liver disease (ALD) have garnered growing research interest in recent times. Alcohol-mediated immune dysfunction has been implicated as a potential cause of ALD-associated microbial infection and inflammatory response. The immune microenvironment of an organism is essentially a complex network of interactions between immune cells, cytokines, extracellular matrix, and other immune-related molecules. This microenvironment is highly adaptive and responsive to environmental cues. Epigenetic reprogramming of the immune microenvironment has recently emerged as a key driver of ALD progression, particularly in the context of endotoxin tolerance and immune disorders. Although epigenetic modifications are known to play an important role in the regulation of the immune microenvironment in ALD, the specific mechanisms and molecular processes by which this regulation is achieved are yet to be fully understood. This paper aims to provide an overview of the current knowledge on the effects of alcohol consumption on epigenetics, with special focus on summarizing the data on the epigenetic regulatory mechanisms involved in the effects of alcohol consumption on the immune microenvironment. In addition, this paper aims to present a review of the epigenetic modifications involved in different forms of ALD. This review is expected to offer new perspectives for the diagnosis, treatment, monitoring, and prognostic assessment of ALD from an epigenetic perspective.

Low‑dose ionizing radiation attenuates high glucose‑induced hepatic apoptosis and immune factor release via modulation of a miR‑155‑SOCS1 axis

Diabetic liver injury (DLI) can result in several diseases of the liver, including steatohepatitis, liver fibrosis, cirrhosis, and liver cancer. Low‑dose ionizing radiation (LDIR) has hormetic effects in normal/disease conditions. However, whether LDIR has a beneficial effect on DLI has not been assessed previously. MicroRNA (miR)‑155 and its target gene suppressor of cytokine signaling 1 (SOCS1) play critical roles in modulating hepatic proliferation, apoptosis, and immunity. However, whether a miR‑155‑SOCS1 axis is involved in high glucose (HG) induced hepatic damage remains to be determined. In the present study, mouse hepatocyte AML12 cells were treated with 30 mM glucose (HG), 75 mGy X‑ray (LDIR), or HG plus LDIR. The expression levels of miR‑155 and SOCS1 were determined by reverse transcription‑quantitative PCR and western blotting. Additionally, apoptosis was measured using flow cytometry. The release of inflammatory factors, including TNF‑α, IL‑1β, IL‑6, IL‑10, and IFN‑γ, after HG and/or LDIR treatment was detected by ELISA. The results showed that HG may induce hepatic apoptosis by upregulating the levels of miR‑155 and downregulating the levels of SOCS1. HG also stimulated the secretion of TNF‑α, IL‑1β, IL‑6, and IL‑10. However, LDIR blocked the HG‑induced activation of a miR‑155‑SOCS1 axis and suppressed the release of inflammatory factors. These results indicated that a miR‑155‑SOCS1 axis plays a role in HG‑induced liver injury, and LDIR may exert a hepatoprotective effect by regulating the miR‑155‑SOCS1 axis.

Mulberry fruit repairs alcoholic liver injury by modulating lipid metabolism and the expression of miR-155 and PPARα in rats

As alcohol consumption increases, alcoholic liver disease (ALD) has become more popular and is threating our human life. In this study, we found mulberry fruit extract (MFE) repaired alcohol-caused liver diseases by regulating hepatic lipid biosynthesis pathway and oxidative singling in alcoholically liver injured (ALI) rats. MFE administration inhibited hepatic lipid accumulation and improved liver steatosis in ALI rats. MFE also enhanced the antioxidant capacity and alleviated the inflammatory response by increasing the activities of antioxidant enzymes and decreasing the contents of interleukin (IL)-1β and tumor necrosis factor (TNF)-α. Additionally, MFE regulated the expression of miRNA-155 and lipid metabolism-related PPARα protein in rats. Both miR-155 and PPARα play important roles in liver function. The results indicate that MFE has hepatoprotective effects against ALI in rats.

Differential Modulation of miR-122 Transcription by TGFβ1/BMP6: Implications for Nonresolving Inflammation and Hepatocarcinogenesis

Chronic inflammation is widely recognized as a significant factor that promotes and worsens the development of malignancies, including hepatocellular carcinoma. This study aimed to explore the potential role of microRNAs in inflammation-associated nonresolving hepatocarcinogenesis. By conducting a comprehensive analysis of altered microRNAs in animal models with liver cancer of various etiologies, we identified miR-122 as the most significantly downregulated microRNA in the liver of animals with inflammation-associated liver cancer. Although previous research has indicated the importance of miR-122 in maintaining hepatocyte function, its specific role as either the trigger or the consequence of underlying diseases remains unclear. Through extensive analysis of animals and in vitro models, we have successfully demonstrated that miR-122 transcription is differentially regulated by the immunoregulatory cytokines, by the transforming growth factor-beta 1 (TGFβ1), and the bone morphogenetic protein-6 (BMP6). Furthermore, we presented convincing evidence directly linking reduced miR-122 transcription to inflammation and in chronic liver diseases. The results of this study strongly suggest that prolonged activation of pro-inflammatory signaling pathways, leading to disruption of cytokine-mediated regulation of miR-122, may significantly contribute to the onset and exacerbation of chronic liver disease.

Accelerated Wound Healing in Diabetic Rat by miRNA-185-5p and Its Anti-Inflammatory Activity

Aim

Addressing both inflammation and epithelialization during the treatment of diabetic foot ulcers is an important step, but current treatment options are limited. MiRNA has important prospects in the treatment of diabetic foot refractory wound ulcers. Previous studies have reported that miR-185-5p reduces hepatic glycogen production and fasting blood glucose levels. We herein hypothesized that miR-185-5p might play an important role in the field of diabetic foot wounds.

Materials and Methods

MiR-185-5p in skin tissue samples from patients with diabetic ulcers and diabetic rats were measured using quantitative real-time PCR (qRT-PCR). The streptozotocin-induced diabetes rat model (male Sprague-Dawley rats) for diabetic wound healing was conducted. The therapeutic potential was observed by subcutaneous injection of miR-185-5p mimic into diabetic rat wounds. The anti-inflammation roles of miR-185-5p on human dermal fibroblast cells were analyzed.

Results

We found that miR-185-5p is significantly downregulated in diabetic skin (people with DFU and diabetic rats) compared to controls. Further, in vitro upregulation of miR-185-5p decreased the inflammatory factors (IL-6, TNF-α) and intercellular adhesion molecule 1 (ICAM-1) of human skin fibroblasts under advanced glycation end products (AGEs). Meanwhile, the increase of miR-185-5p promoted cell migration. Our results also confirmed that the topical increase of miR-185-5p decreases diabetic wound p-nuclear factor-κB (p-NF-κB), ICAM-1, IL-6, TNF-α, and CD68 expression in diabetic wounds. MiR-185-5p overexpression boosted re-epithelization and expedited wound closure of diabetic rats.

Conclusion

MiR-185-5p accelerated wound healing of diabetic rats, reepithelization, and inhibited the inflammation of diabetic wounds in the healing process, a potentially new and valid treatment for refractory diabetic foot ulcers.

Pathogenic mechanisms and regulatory factors involved in alcoholic liver disease

Alcoholism is a widespread and damaging behaviour of people throughout the world. Long-term alcohol consumption has resulted in alcoholic liver disease (ALD) being the leading cause of chronic liver disease. Many metabolic enzymes, including alcohol dehydrogenases such as ADH, CYP2E1, and CATacetaldehyde dehydrogenases ALDHsand nonoxidative metabolizing enzymes such as SULT, UGT, and FAEES, are involved in the metabolism of ethanol, the main component in alcoholic beverages. Ethanol consumption changes the functional or expression profiles of various regulatory factors, such as kinases, transcription factors, and microRNAs. Therefore, the underlying mechanisms of ALD are complex, involving inflammation, mitochondrial damage, endoplasmic reticulum stress, nitrification, and oxidative stress. Moreover, recent evidence has demonstrated that the gut-liver axis plays a critical role in ALD pathogenesis. For example, ethanol damages the intestinal barrier, resulting in the release of endotoxins and alterations in intestinal flora content and bile acid metabolism. However, ALD therapies show low effectiveness. Therefore, this review summarizes ethanol metabolism pathways and highly influential pathogenic mechanisms and regulatory factors involved in ALD pathology with the aim of new therapeutic insights.

Recent advances in the role of exosomes in liver fibrosis

BACKGROUND AND AIM

We aim to summarize the current status of research on the role of exosomes in liver fibrosis.

METHODS

A review of the relevant literature was performed and the key findings were presented.

RESULTS

Most studies focused on the role of exosomes derived from mesenchymal stem cells, other types of stem cells, and liver resident cells including hepatocytes, cholangiocytes, and hepatic stellate cells in liver fibrosis. Exosomes have been reported to play an essential role in the inactivation or activation of hepatic stellate cells through the delivery of non-coding RNAs and proteins. In recent years, this exosome cargo has become a research hotspot.

CONCLUSIONS

Recent studies have indicated the potential therapeutic benefit of exosomes in liver fibrosis.

Fatty Liver Disease, Metabolism and Alcohol Interplay: A Comprehensive Review

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide, and its incidence has been increasing in recent years because of the high prevalence of obesity and metabolic syndrome in the Western population. Alcohol-related liver disease (ArLD) is the most common cause of cirrhosis and constitutes the leading cause of cirrhosis-related deaths worldwide. Both NAFLD and ArLD constitute well-known causes of liver damage, with some similarities in their pathophysiology. For this reason, they can lead to the progression of liver disease, being responsible for a high proportion of liver-related events and liver-related deaths. Whether ArLD impacts the prognosis and progression of liver damage in patients with NAFLD is still a matter of debate. Nowadays, the synergistic deleterious effect of obesity and diabetes is clearly established in patients with ArLD and heavy alcohol consumption. However, it is still unknown whether low to moderate amounts of alcohol are good or bad for liver health. The measurement and identification of the possible synergistic deleterious effect of alcohol consumption in the assessment of patients with NAFLD is crucial for clinicians, since early intervention, advising abstinence and controlling cardiovascular risk factors would improve the prognosis of patients with both comorbidities. This article seeks to perform a comprehensive review of the pathophysiology of both disorders and measure the impact of alcohol consumption in patients with NAFLD.

Peroxisome Proliferator-Activated Receptor-γ as a Target and Regulator of Epigenetic Mechanisms in Nonalcoholic Fatty Liver Disease

Peroxisome proliferator-activated receptor-γ (PPARγ) belongs to the superfamily of nuclear receptors that control the transcription of multiple genes. Although it is found in many cells and tissues, PPARγ is mostly expressed in the liver and adipose tissue. Preclinical and clinical studies show that PPARγ targets several genes implicated in various forms of chronic liver disease, including nonalcoholic fatty liver disease (NAFLD). Clinical trials are currently underway to investigate the beneficial effects of PPARγ agonists on NAFLD/nonalcoholic steatohepatitis. Understanding PPARγ regulators may therefore aid in unraveling the mechanisms governing the development and progression of NAFLD. Recent advances in high-throughput biology and genome sequencing have greatly facilitated the identification of epigenetic modifiers, including DNA methylation, histone modifiers, and non-coding RNAs as key factors that regulate PPARγ in NAFLD. In contrast, little is still known about the particular molecular mechanisms underlying the intricate relationships between these events. The paper that follows outlines our current understanding of the crosstalk between PPARγ and epigenetic regulators in NAFLD. Advances in this field are likely to aid in the development of early noninvasive diagnostics and future NAFLD treatment strategies based on PPARγ epigenetic circuit modification.

Berberine attenuates liver fibrosis by autophagy inhibition triggering apoptosis via the miR-30a-5p/ATG5 axis

Berberine (BBR) is an effective drug against liver fibrosis (LF). Autophagy is involved in the pathogenesis of LF; however, the mechanism linking BBR to autophagy in LF remains unresolved. To explore the underlying mechanism, we assessed the effects of BBR on autophagy and apoptosis of activated hepatic stellate cells (HSCs) in vitro and in a murine model of fibrosis. The decreased expression of the autophagy activation marker ATG5, autophagosome formation, and autophagy flux in the HSC model confirmed that BBR inhibited autophagy in activated HSCs and in mice with liver fibrosis. Moreover, ATG5 was necessary for inducing autophagy and HSC activation. BBR suppressed ATG5 expression by upregulating miR-30a-5p expression, which affected the stability of ATG5 mRNA by binding to its 3'-untranslated region, an effect that was attenuated by treatment with a miR-30a-5p inhibitor. BBR also markedly induced HSC apoptosis, as indicated by the upregulated expression of the pro-apoptosis markers p53, BAX, and cleaved PARP and the downregulated expression of the anti-apoptosis marker BCL-2, effects that were reversed by ATG5 overexpression. In vivo, BBR improved mouse LF by decreasing collagen deposition, inflammatory cell infiltration, and expression of fibrosis markers hydroxyproline, α-smooth muscle actin, and collagen type 1-A1 and the autophagy marker LC3. BBR had a protective effect on mouse fibrotic livers and reduced serum aspartate aminotransferase and alanine aminotransferase levels. Collectively, these results reveal a novel mechanism of BBR-induced autophagy inhibition triggering apoptosis in HSCs, providing a reliable experimental and theoretical basis for developing BBR-based candidate drugs for LF.

Modulation of macrophage polarization by iron-based nanoparticles

Macrophage polarization is an essential process involved in immune regulation. In response to different microenvironmental stimulation, macrophages polarize into cells with different phenotypes and functions, most typically M1 (pro-inflammatory) and M2 (anti-inflammatory) macrophages. Iron-based nanoparticles have been widely explored and reported to regulate macrophage polarization for various biomedical applications. However, the influence factors and modulation mechanisms behind are complicated and not clear. In this review, we systemically summarized different iron-based nanoparticles that regulate macrophage polarization and function and discussed the influence factors and mechanisms underlying the modulation process. This review aims to deepen the understanding of the modulation of macrophage polarization by iron-based nanoparticles and expects to provide evidence and guidance for subsequent design and application of iron-based nanoparticles with specific macrophage modulation functions.

Regulation of NOX/p38 MAPK/PPARα pathways and miR-155 expression by boswellic acids reduces hepatic injury in experimentally-induced alcoholic liver disease mouse model: novel mechanistic insight

Alcoholic liver disease (ALD) refers to hepatic ailments induced by excessive alcohol intake. The pathogenesis of ALD comprises a complex interplay between various mechanistic pathways, among which inflammation and oxidative stress are key players. Boswellic acids (BAs), found in Boswellia serrata, have shown hepatoprotective effects owing to their antioxidant and anti-inflammatory activities, nevertheless, their therapeutic potential against ALD has not been previously investigated. Hence, this study was performed to depict the possible protective effect of BAs and detect their underlying mechanism of action in an experimentally-induced ALD mouse model. Male BALB/c mice were equally categorized into six groups: control, BAs-treated, ALD, and ALD that received BAs at three-dose levels (125, 250, and 500 mg/kg) by oral gavage for 14 days. Results showed that the high dose of BAs had the most protective impact against ALD according to histopathology examination, blood alcohol concentration (BAC), and liver function enzymes. Mechanistic investigations revealed that BAs (500 mg/kg) caused a significant decrease in cytochrome P450 2E1(CYP2E1), nicotine adenine dinucleotide phosphate oxidase (NOX) 1/2/4, p38 mitogen-activated protein kinase (MAPK), and sterol regulatory element-binding protein-1c (SREBP-1c) levels, and the expression of miR-155, yet increased peroxisome proliferator-activated receptor alpha (PPARα) levels. This led to an improvement in lipid profile and reduced hepatic inflammation, oxidative stress, and apoptosis indices. In summary, our study concludes that BAs can protect against ethanol-induced hepatic injury, via modulating NOX/p38 MAPK/PPARα pathways and miR-155 expression.

The role of miR-155 on liver diseases by modulating immunity, inflammation and tumorigenesis

The liver is a well-known metabolic organ that can be susceptible to external stimuli to affect its normal physiological function. Worldwide, the morbidity and mortality of liver diseases are skyrocketing every year, causing human health crises. Recently, new approaches such as biotechnology have been introduced to achieve optimal treatment and prognostic management of liver diseases. microRNAs (miRNAs), a kind of small non-coding RNA molecule, have the advantages of biodiversity, wide distribution and numerous members. Among these miRNAs, miR-155 is an important regulator of inflammation, immunity and tumorigenesis. In this review, the PubMed and Web of Science databases were searched from 2009 to 2022. After inclusion and exclusion, 64 articles were selected for a systematic review to comprehensively summarize the mechanisms of miR-155 regulating inflammation, immunity and tumorigenesis in liver diseases and liver cancer, covering in vitro, in vivo and clinical studies. Existing preclinical studies and clinical trials have listed that the up-regulation and down-regulation of miR-155 are significant in alcoholic liver injury, viral hepatitis, autoimmune hepatitis, infectious liver injury, liver transplantation and liver cancer. The immune and inflammation effects of miR-155 are manifested by regulating macrophage polarization, NK cell killing, Th17 cell and Th1/Th2 cell differentiation. Additionally, miR-155 is also committed to participating in the cell cycle, invasion and metastasis, immune escape and other processes to promote and intensify the development of liver cancer. In conclusion, miR-155 is not only a biomarker for the diagnosis and prognosis of liver diseases, but also plays a therapeutic role via regulating immunity, inflammation and tumorigenesis.

Green tea actions on miRNAs expression – An update

Compounds derived from plants have been widely studied in the context of metabolic diseases and associated clinical conditions. In this regard, although the effects of Camellia sinensis plant, from which various types of teas, such as green tea, originate, have been vastly reported in the literature, the mechanisms underlying these effects remain elusive. A deep search of the literature showed that green tea's action in different cells, tissues, and diseases is an open field in the research of microRNAs (miRNAs). miRNAs are important communicator molecules between cells in different tissues implicated in diverse cellular pathways. They have emerged as an important linkage between physiology and pathophysiology, raising the issue of polyphenols can act also by changing miRNA expression. miRNAs are short, non-coding endogenous RNA, which silence the gene functions by targeting messenger RNA (mRNA) through degradation or translation repression. Therefore, the aim of this review is to present the studies that show the main compounds of green tea modulating the expression of miRNAs in inflammation, adipose tissue, skeletal muscle, and liver. We provide an overview of a few studies that have tried to demonstrate the role of miRNAs associated with the beneficial effects of compounds from green tea. We have emphasized that there is still a considerable gap in the literature investigating the role and likely involvement of miRNAs in the extensive beneficial health effects of green tea compounds already described, indicating miRNAs as potential polyphenols' mediators with a promising field to be investigated.

The role of miRNAs in liver diseases: Potential therapeutic and clinical applications

MicroRNAs (miRNAs) are a class of short, non-coding RNAs that function post-transcriptionally to regulate gene expression by binding to particular mRNA targets and causing destruction of the mRNA or translational inhibition of the mRNA. The miRNAs control the range of liver activities, from the healthy to the unhealthy. Considering that miRNA dysregulation is linked to liver damage, fibrosis, and tumorigenesis, miRNAs are a promising therapeutic strategy for the evaluation and treatment of liver illnesses. Recent findings on the regulation and function of miRNAs in liver diseases are discussed, with an emphasis on miRNAs that are highly expressed or enriched in hepatocytes. Alcohol-related liver illness, acute liver toxicity, viral hepatitis, hepatocellular carcinoma, liver fibrosis, liver cirrhosis, and exosomes in chronic liver disease all emphasize the roles and target genes of these miRNAs. We briefly discuss the function of miRNAs in the etiology of liver diseases, namely in the transfer of information between hepatocytes and other cell types via extracellular vesicles. Here we offer some background on the use of miRNAs as biomarkers for the early prognosis, diagnosis, and assessment of liver diseases. The identification of biomarkers and therapeutic targets for liver disorders will be made possible by future research into miRNAs in the liver, which will also help us better understand the pathogeneses of liver diseases.

Elevated Placental microRNA-155 Is a Biomarker of a Preeclamptic Subtype

BACKGROUND

Preeclampsia is a complicated syndrome with marked heterogeneity. The biomarker-based classification for this syndrome is more constructive to the targeted prevention and treatment of preeclampsia. It has been reported that preeclamptic patients had elevated microRNA-155 (miR-155) in placentas or circulation. Here, we investigated the characteristics of patients with high placental miR-155 (pl-miR-155).

METHODS

Based on the 95th percentile (P95) of pl-miR-155 in controls, preeclamptic patients were divided into high miR-155 group (≥P95) and normal miR-155 group (<P95). The changes of placental pathology, clinical manifestations, and placental transcriptome of preeclamptic patients were clustered by t-distributed stochastic neighbor embedding and hierarchical clustering analysis. The placental restricted miR-155 overexpression mouse model was constructed, and the phenotype, placental pathology, and transcriptome were evaluated. Furthermore, the therapeutic potential of antagonist of miR-155 was explored by administrating with antagomir-155.

RESULTS

About one-third of preeclamptic patients had high pl-miR-155 expression, which was positively correlated with circulating miR-155 levels. These patients could be clustered as 1 group, according to clinical manifestation, placental pathology, or transcriptomes by t-distributed stochastic neighbor embedding and hierarchical clustering analysis. Further, the pregnant mice with placental restricted miR-155 overexpression could simulate the changes of clinical signs, pathology, and transcriptome of placentas in patients with high pl-miR-155. AntagomiR-155 treatment relieved the preeclampsia-like phenotype and improved the placental vascular development in mice.

CONCLUSIONS

There is at least 1 type of preeclampsia with upregulated miR-155 presenting more severe clinical manifestations. MiR-155 may be a potential therapeutic target in patients with high pl-miR-155.

Regulatory Functions and Mechanisms of Circular RNAs in Hepatic Stellate Cell Activation and Liver Fibrosis

Chronic liver injury induces the activation of hepatic stellate cells (HSCs) into myofibroblasts, which produce excessive amounts of extracellular matrix (ECM), resulting in tissue fibrosis. If the injury persists, these fibrous scars could be permanent and disrupt liver architecture and function. Currently, effective anti-fibrotic therapies are lacking; hence, understanding molecular mechanisms that control HSC activation could hold a key to the development of new treatments. Recently, emerging studies have revealed roles of circular RNAs (circRNAs), a class of non-coding RNAs that was initially assumed to be the result of splicing errors, as new regulators in HSC activation. These circRNAs can modulate the activity of microRNAs (miRNAs) and their interacting protein partners involved in regulating fibrogenic signaling cascades. In this review, we will summarize the current knowledge of this class of non-coding RNAs for their molecular function in HSC activation and liver fibrosis progression.

Mir155 regulates osteogenesis and bone mass phenotype via targeting S1pr1 gene

MicroRNA-155 (miR155) is overexpressed in various inflammatory diseases and cancer, in which bone resorption and osteolysis are frequently observed. However, the role of miR155 on osteogenesis and bone mass phenotype is still unknown. Here, we report a low bone mass phenotype in the long bone of Mir155-Tg mice compared with wild-type mice. In contrast, Mir155-KO mice showed a high bone mass phenotype and protective effect against inflammation-induced bone loss. Mir155-KO mice showed robust bone regeneration in the ectopic and orthotopic model, but Mir155-Tg mice showed compromised bone regeneration compared with the wild-type mice. Similarly, the osteogenic differentiation potential of bone marrow stromal stem cells (BMSCs) from Mir155-KO mice was robust and Mir155-Tg was compromised compared with that of wild-type mice. Moreover, Mir155 knockdown in BMSCs from wild-type mice showed higher osteogenic differentiation potential, supporting the results from Mir155-KO mice. TargetScan analysis predicted sphingosine 1-phosphate receptor-1 (S1pr1) as a target gene of Mir155, which was further confirmed by luciferase assay and Mir155 knockdown. S1pr1 overexpression in BMSCs robustly promoted osteogenic differentiation without affecting cell viability and proliferation. Furthermore, osteoclastogenic differentiation of Mir155-Tg bone marrow-derived macrophages was inhibited compared with that of wild-type mice. Thus, Mir155 showed a catabolic effect on osteogenesis and bone mass phenotype via interaction with the S1pr1 gene, suggesting inhibition of Mir155 as a potential strategy for bone regeneration and bone defect healing.

Ongoing involvers and promising therapeutic targets of hepatic fibrosis: The hepatic immune microenvironment

Hepatic fibrosis is often secondary to chronic inflammatory liver injury. During the development of hepatic fibrosis, the damaged hepatocytes and activated hepatic stellate cells (HSCs) caused by the pathogenic injury could secrete a variety of cytokines and chemokines, which will chemotactic innate and adaptive immune cells of liver tissue and peripheral circulation infiltrating into the injury site, mediating the immune response against injury and promoting tissue reparation. However, the continuous release of persistent injurious stimulus-induced inflammatory cytokines will promote HSCs-mediated fibrous tissue hyperproliferation and excessive repair, which will cause hepatic fibrosis development and progression to cirrhosis even liver cancer. And the activated HSCs can secrete various cytokines and chemokines, which directly interact with immune cells and actively participate in liver disease progression. Therefore, analyzing the changes in local immune homeostasis caused by immune response under different pathological states will greatly enrich our understanding of liver diseases' reversal, chronicity, progression, and even deterioration of liver cancer. In this review, we summarized the critical components of the hepatic immune microenvironment (HIME), different sub-type immune cells, and their released cytokines, according to their effect on the development of progression of hepatic fibrosis. And we also reviewed and analyzed the specific changes and the related mechanisms of the immune microenvironment in different chronic liver diseases.Moreover, we retrospectively analyzed whether the progression of hepatic fibrosis could be alleviated by modulating the HIME.We aimed to elucidate the pathogenesis of hepatic fibrosis and provide the possibility for exploring the therapeutic targets for hepatic fibrosis.

MiR-342-5p protects neurons from cerebral ischemia induced-apoptosis through regulation of Akt/NF-κB pathways by targeting CCAR2

OBJECTIVES

Ischemic stroke causes high morbidity, mortality and health burden in the world. MiR-342-5p was associated with Alzheimer's disease and cardio-protection. Herein, we aimed to reveal effects of miR-342-5p on cerebral ischemia injury as well as novel targets for stroke.

MATERIALS AND METHODS

AgomiR-342-5p was intracerebroventricularly injected into the middle cerebral artery occlusion (MCAO) mouse models to evaluate functions of miR-342-5p on cerebral ischemia. RT-qPCR and western blot assays were used to evaluate genes expression. Oxygen-glucose deprivation (OGD) was used as an in vitro model for ischemia. Viability and apoptosis ratio of neurons was evaluated by CCK-8, LDH release detection, and flow cytometry. The potential targets of miR-342-5p were predicted by Targetscan, and their interaction was confirmed by luciferase assay.

RESULTS

The intervention of miR-342-5p effectively attenuated ischemic injury in MCAO mice. MiR-342-5p overexpression could protect neurons against OGD-induced injury, as revealed by increased cell viability and BCL2 expression, and decreased LDH release, apoptosis ratio, and BAX expression in OGD-induced neurons. Mechanically, miR-342-5p could directly bound with CCAR2 to inhibit its expression. Overexpressing CARR2 aggravated the OGD-induced injury of neurons, which was partly restrained by overexpressing miR-342-5p reversed. Furthermore, miR-342-5p/CARR2 axis regulates Akt/NF-κB signaling pathway in vitro as well as in vivo cerebral ischemia models.

CONCLUSIONS

MiR-342-5p inhibited neuron apoptosis by regulating Akt/NF-kB signaling pathway via CCAR2 suppression. Our findings revealed the neuroprotection of miR-342-5p in cerebral ischemia.

MiR-155-5p-SOCS1/JAK1/STAT1 participates in hepatic lymphangiogenesis in liver fibrosis and cirrhosis by regulating M1 macrophage polarization

BACKGROUND

The role and underlying mechanism of liver macrophages and their derived miR-155-5p in hepatic lymphangiogenesis in liver fibrosis remain unclear. Here, we investigated the mechanism by which macrophages and miR-155-5p were involved in lymphangiogenesis during liver fibrosis and cirrhosis.

METHODS

In vivo, hepatic lymphatic vessel expansion was evaluated; the liver macrophage subsets, proportion of peripherally-derived macrophages and expressions of CCL25, MCP-1, VAP-1 and MAdCAM-1 were documented; and miR-155-5p in the peripheral blood and liver was detected. In vitro, macrophages with miR-155-5p overexpression and inhibition were used to clarify the effect of miR-155-5p on regulation of macrophage polarization and the possible signalling pathway.

RESULTS

Hepatic lymphangiogenesis was observed in mice with liver fibrosis and cirrhosis challenged with carbon tetrachloride (CCl4). In the liver, the number of M1 macrophages was associated with lymphangiogenesis and the degree of fibrosis. The liver recruitment of peripherally-derived macrophages occurred during liver fibrosis. The levels of miR-155-5p in the liver and peripheral blood gradually increased with aggravation of liver fibrosis. In vitro, SOCS1, a target of miR-155-5p, regulated macrophage polarization into the M1 phenotype through the JAK1/STAT1 pathway.

CONCLUSION

MiR-155-5p-SOCS1/JAK1/STAT1 pathway participates in hepatic lymphangiogenesis in mice with liver fibrosis and cirrhosis induced by CCl4 by regulating the polarization of macrophages into the M1 phenotype.

MicroRNA: role in macrophage polarization and the pathogenesis of the liver fibrosis

Macrophages, as central components of innate immunity, feature significant heterogeneity. Numerus studies have revealed the pivotal roles of macrophages in the pathogenesis of liver fibrosis induced by various factors. Hepatic macrophages function to trigger inflammation in response to injury. They induce liver fibrosis by activating hepatic stellate cells (HSCs), and then inflammation and fibrosis are alleviated by the degradation of the extracellular matrix and release of anti-inflammatory cytokines. MicroRNAs (miRNAs), a class of small non-coding endogenous RNA molecules that regulate gene expression through translation repression or mRNA degradation, have distinct roles in modulating macrophage activation, polarization, tissue infiltration, and inflammation regression. Considering the complex etiology and pathogenesis of liver diseases, the role and mechanism of miRNAs and macrophages in liver fibrosis need to be further clarified. We first summarized the origin, phenotypes and functions of hepatic macrophages, then clarified the role of miRNAs in the polarization of macrophages. Finally, we comprehensively discussed the role of miRNAs and macrophages in the pathogenesis of liver fibrotic disease. Understanding the mechanism of hepatic macrophage heterogeneity in various types of liver fibrosis and the role of miRNAs on macrophage polarization provides a useful reference for further research on miRNA-mediated macrophage polarization in liver fibrosis, and also contributes to the development of new therapies targeting miRNA and macrophage subsets for liver fibrosis.

MicroRNAs: Small molecules with big impacts in liver injury

A type of small noncoding RNAs known as microRNAs (miRNAs) fine-tune gene expression posttranscriptionally by binding to certain messenger RNA targets. Numerous physiological processes in the liver, such as differentiation, proliferation, and apoptosis, are regulated by miRNAs. Additionally, there is growing evidence that miRNAs contribute to liver pathology. Extracellular vesicles like exosomes, which contain secreted miRNAs, may facilitate paracrine and endocrine communication between various tissues by changing the gene expression and function of distal cells. The use of stable miRNAs as noninvasive biomarkers was made possible by the discovery of these molecules in body fluids. Circulating miRNAs reflect the conditions of the liver that are abnormal and may serve as new biomarkers for the early detection, prognosis, and evaluation of liver pathological states. miRNAs are appealing therapeutic targets for a range of liver disease states because altered miRNA expression is associated with deregulation of the liver's metabolism, liver damage, liver fibrosis, and tumor formation. This review provides a comprehensive review and update on miRNAs biogenesis pathways and mechanisms of miRNA-mediated gene silencing. It also outlines how miRNAs affect hepatic cell proliferation, death, and regeneration as well as hepatic detoxification. Additionally, it highlights the diverse functions that miRNAs play in the onset and progression of various liver diseases, including nonalcoholic fatty liver disease, alcoholic liver disease, fibrosis, hepatitis C virus infection, and hepatocellular carcinoma. Further, it summarizes the diverse liver-specific miRNAs, illustrating the potential merits and possible caveats of their utilization as noninvasive biomarkers and appealing therapeutic targets for liver illnesses.