MicroRNA-122-5p Inhibition Improves Inflammation and Oxidative Stress Damage in Dietary-Induced Non-alcoholic Fatty Liver Disease Through Targeting FOXO3

Pathophysiological underpinnings of metabolic dysfunction-associated steatotic liver disease

Metabolic dysfunction-associated steatotic liver disease (MASLD) is emerging as the leading cause of chronic liver disease worldwide, reflecting the global epidemics of obesity, metabolic syndrome, and type 2 diabetes. Beyond its strong association with excess adiposity, MASLD encompasses a heterogeneous population that includes individuals with normal body weight ("lean MASLD") highlighting the complexity of its pathogenesis. This disease results from a complex interplay between genetic susceptibility, epigenetic modifications, and environmental factors, which converge to disrupt metabolic homeostasis. Adipose tissue dysfunction and insulin resistance trigger an overflow of lipids to the liver, leading to mitochondrial dysfunction, oxidative stress, and hepatocellular injury. These processes promote hepatic inflammation and fibrogenesis, driven by cross talk among hepatocytes, immune cells, and hepatic stellate cells, with key contributions from gut-liver axis perturbations. Recent advances have unraveled pivotal molecular pathways, such as transforming growth factor-β signaling, Notch-induced osteopontin, and sphingosine kinase 1-mediated responses, that orchestrate fibrogenic activation. Understanding these interconnected mechanisms is crucial for developing targeted therapies. This review integrates current knowledge on the pathophysiology of MASLD, emphasizing emerging concepts such as lean metabolic dysfunction-associated steatohepatitis (MASH), epigenetic alterations, hepatic extracellular vesicles, and the relevance of extrahepatic signals. It also discusses novel therapeutic strategies under investigation, aiming to provide a comprehensive and structured overview of the evolving MASLD landscape for both basic scientists and clinicians.

Connecting the Dots: How MicroRNAs Link Asthma and Atherosclerosis

Asthma and atherosclerosis are chronic conditions with distinct pathophysiologies, but overlapping inflammatory mechanisms that suggest a potential common regulatory framework. MicroRNAs (miRNAs), small non-coding RNA molecules that modulate gene expression post-transcriptionally, could be key players in linking these disorders. This review outlines how miRNAs contribute to the complex interplay between asthma and atherosclerosis, focusing on key miRNAs involved in inflammatory pathways, immune cell regulation and vascular remodeling. We discuss specific miRNAs, such as miR-155, miR-21 and miR-146a, which have been shown to modulate inflammatory cytokine production and T cell differentiation, impacting respiratory and cardiovascular health. The common miRNAs found in both asthma and atherosclerosis emphasize their role as potential biomarkers, but also as therapeutic targets. Understanding these molecular connections may unlock novel approaches for innovative, integrated treatment strategies that address both conditions and may significantly improve patient outcomes. Further research is needed to explore mechanistic pathways and validate the translational potential of miRNA-based interventions in preclinical and clinical settings.

Association between single nucleotide polymorphisms in PNPLA3, TM6SF2 and MBOAT7 genes and markers of cancer aggressiveness in a Sri Lankan NASH-related HCC cohort

BACKGROUND

Single nucleotide polymorphisms (SNPs) in patatin-like phospholipase domain-containing protein 3 (PNPLA3), transmembrane 6 superfamily member 2 (TM6SF2) and membrane bound O-acyltransferase domain containing 7 (MBOAT7) genes were reported to be strongly associated with non-alcoholic fatty liver disease (NAFLD) pathogenicity among different populations. We investigated whether these SNPs are associated with prognostic factors and genetic biomarkers of non-alcoholic steatohepatitis (NASH)-related hepatocellular carcinoma (HCC) in the Sri Lankan context.

METHODS

We conducted an exploratory study to evaluate the prevalence of five SNPs (PNPLA3 rs738409, PNPLA3 rs2281135, PNPLA3 rs2294918, TM6SF2 rs58542926 and MBOAT7 rs641738) as genetic risk factors for NASH-HCC pathogenicity. We genotyped 48 NASH-HCC patient samples collected at a clinical setting using a minisequencing method. Impact of each SNP with tumor prognostic factors such as nodularity, tumor size and AFP (alpha-feto protein) level was analyzed using chi square test. We also analyzed the expression of micro RNA-122 (miR-122) in serum and leukocyte telomere length via quantitative real-time PCR. Associations between each SNP with micro RNA-122 (miR-122) expression level and leukocyte telomere length of NASH-HCC patients were analyzed using one-way analysis of variance (ANOVA) test and independent t test. Relationships among tested SNPs and some well-established HCC risk factors such as age, BMI, gender, diabetes status and the cirrhotic stage were also analyzed using chi square test, independent t-test and One-way ANOVA test.

RESULTS

Our analyses demonstrated significant associations between PNPLA3 rs2281135 variant and tumor nodularity. Also, PNPLA3 rs2281135 and PNPLA3 rs2294918 variants were significantly associated with miR-122 expression levels of NASH-HCC patients. Further, age and body mass index (BMI) were significantly associated with PNPLA3 rs2281135 variant in our study cohort.

CONCLUSION

We found that in the Sri Lankan NASH-related HCC cohort, some PNPLA3 variants (rs2281135 and rs2294918) correlate with tumor nodularity, higher miR-122 expression, and distinct demographic features such as age and BMI. Our work highlights the role of specific SNPs in tumor aggressiveness, contributing to the precision screening for HCC in NASH patients.

Regulatory Roles and Therapeutic Potential of miR-122-5p in Hypoxic-Ischemic Brain Injury: Comprehensive Review

In the regulation of gene expression, epigenetic factors, including non-coding RNAs (ncRNAs) play a role in genetics. Among the ncRNA family, microRNAs (miRNAs) have gained significant attention for their involvement in post-transcriptional gene regulation, with profound implications for both normal and pathological processes including neurological diseases such as hypoxic-ischemic brain injury. A specific miRNA, called miR-122-5p, has gained attention in hypoxic-ischemic conditions, where it modulates critical pathways such as inflammation, oxidative stress, and neuronal survival. The purpose of this review is to highlight recent advances in the biogenesis, expression, and regulation of miR-122-5p, focusing on its role in hypoxic-ischemic conditions and its potential as a therapeutic target. We first studied the therapeutic strategies and potential clinical applications of miR-122-5p, our research showing it interacts with key transcription factors, such as HIF-1α and NF-κB, influencing cellular responses to low oxygen levels. Our findings revealed that miR-122-5p plays a vital role in hypoxic-ischemic brain injury, with its abnormal levels strongly associated with increased brain damage and neuroinflammation, suggesting its potential as a promising therapeutic target. Furthermore, miR-122-5p influences various biological processes in the brain, such as metabolism and blood vessel formation. The use of miR-122-5p inhibitor has been shown to increase autophagy, reduce apoptosis, and decrease oxidative stress and inflammation, thereby protecting neurons and improving outcomes in hypoxic encephalopathy by targeting multiple genes related to these processes. Conversely, miR-122-5p mimics exacerbate oxidative stress and reduce autophagy. These findings highlight the therapeutic potential of miR-122-5p inhibition in reducing brain injury and promoting recovery in hypoxic-ischemic encephalopathy through enhanced neuroprotective mechanisms and the suppression of harmful cellular processes. However, further experimental studies are needed to fully understand the therapeutic potential of targeting miR-122-5p and its related genes in hypoxic-ischemic encephalopathy.

From fatty liver to fibrosis: the impact of miRNAs on NAFLD and NASH

Non-alcoholic fatty liver disease (NAFLD) is a disease with various levels varying from fatty liver steatosis to acute steatosis which is non-alcoholic steatohepatitis (NASH), which can develop into hepatic failure, as well as in some conditions it can develop into hepatocellular carcinoma (HCC). In the NAFLD and NASH context, aberrant microRNA (miRNA) expression has a thorough contribution to the incidence and development of these liver disorders by influencing key biological actions, involving lipid metabolism, inflammation, and fibrosis. Dysregulated miRNAs can disrupt the balance between lipid accumulation and clearance, exacerbate inflammatory responses, and promote fibrogenesis, thus advancing the severeness of the disorder from simple steatosis to more complex NASH. In the current review, the latest development concerned with the activity of complex regulatory networks of miRNA in the incidence as well as the evolution of NAFLD is to be discussed, also conferring about the miRNAs' role in the onset, pathogenesis as well as diagnosis of NAFLD and NASH discussing miRNAs' role as diagnostic biomarkers and their therapeutic effects on NAFLD/NASH.

Comprehensive profiling of serum microRNAs in normal and non-alcoholic fatty liver disease (NAFLD) patients

Pediatric non-alcoholic fatty liver disease (NAFLD) is emerging as a worldwide health concern with the potential to advance to cirrhosis and liver cancer. NAFLD can also directly contribute to heart problems through inflammation and insulin resistance, even in individuals without other risk factors. The pathological mechanisms of NAFLD are linked to functional differences of miRNAs in different biological environments. The miRNA in serum exosomes may reflect the pathological state of the liver and changes in systemic metabolism, while the miRNA in serum may be associated with physiological processes other than the liver. Pediatric non-alcoholic fatty liver disease (NAFLD) is emerging as a worldwide health concern with the potential to advance to cirrhosis and liver cancer. NAFLD can also directly contribute to heart problems through inflammation and insulin resistance, even in individuals without other risk factors. The pathological mechanisms of NAFLD are linked to functional differences of miRNAs in different biological environments. The miRNA in serum exosomes may reflect the pathological state of the liver and changes in systemic metabolism, while the miRNA in serum may be associated with physiological processes other than the liver. Pediatric non-alcoholic fatty liver disease (NAFLD) is emerging as a worldwide health concern with the potential to advance to cirrhosis and liver cancer. NAFLD can also directly contribute to heart problems through inflammation and insulin resistance, even in individuals without other risk factors. The pathological mechanisms of NAFLD are linked to functional differences of miRNAs in different biological environments. The miRNA in serum exosomes may reflect the pathological state of the liver and changes in systemic metabolism, while the miRNA in serum may be associated with physiological processes other than the liver. Our study identified 36 miRNAs with differential expression in the serum of NAFLD patients compared to the control group, including 21 miRNAs with significantly increased expression and 15 with decreased expression. Consistent with our previously reported data on serum-derived exosomal miRNA profiling, this study also observed a notable upregulation of serum miR-122-5p levels in NAFLD patients. PCR validation confirmed the differential expression of miR-122-5p identified through RNA sequencing. Functional analysis using GO and KEGG pathways revealed a diverse range of biological roles associated with these differentially expressed miRNAs. Notably, NAFLD significantly impacts heart health, with miR-122-5p playing a key role in regulating cardiovascular function. Furthermore, activation of the miR-122/Sirt-6/ACE2 axis may contribute to myocardial necrosis, highlighting its potential role in NAFLD-associated cardiovascular risks. Our study suggests that miR-122 plays a key role in the progression of NAFLD and its associated metabolic disturbances, which can increase the risk of cardiovascular disease. Targeting miR-122 may offer potential therapeutic benefits for improving both liver and heart health in individuals with NAFLD.

MicroRNA-122 protects against interferon-α-induced hepatic inflammatory response via the Janus kinase-signal transducer and activator of transcription pathway

Significant overlap in the epidemiology and coinfection of chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) has been identified, which accelerates the development of severe liver cirrhosis and hepatocellular carcinoma worldwide. Interferon-α (IFN-α), a cytokine with antiviral properties, exerts profound physiological effects on innate immunity by regulating interferon-stimulated genes (ISGs) within cells. However, the underlying mechanism of IFN-α in hepatic inflammation remains to be fully elucidated. Here, we utilized LO2 cells treated with the recombinant IFN-α protein and conducted microRNA (miR) sequencing. MiR-122-3p and miR-122-5p_R+1 were the most enriched miRNAs involved in the pathogenesis of IFN-α-induced inflammatory responses and were significantly downregulated by IFN-α treatment. Furthermore, we identified interferon induced protein with tetratricopeptide repeats 1 (IFIT1) as a potential target gene of miR-122. IFN-α markedly increased the expression of proinflammatory cytokines and fibrogenic genes but decreased the mRNA expression of ISGs. Additionally, IFN-α significantly activated the NF-κB p-p65, MAPK p-p38, and Jak/STAT pathways to trigger inflammation. Importantly, supplementation with a miR-122 mimic significantly alleviated IFN-α-induced inflammation and induced IFIT1 expression in LO2 cells. Conversely, the suppression of miR-122 markedly exacerbated the inflammatory response triggered by IFN-α. Furthermore, silencing IFIT1 via an siRNA elicited an inflammatory response, whereas IFIT1 overexpression ameliorated hepatic inflammation and fibrosis in a manner comparable to that induced by IFN-α treatment. Taken together, our findings suggest that miR-122 and its target, IFIT1, reciprocally regulate the inflammatory response associated with IFN through the Jak/STAT pathway.

Second-Generation Antipsychotics Induce Metabolic Disruption in Adipose Tissue-Derived Mesenchymal Stem Cells Through an aPKC-Dependent Pathway

Metabolic syndrome (MetS) is a cluster of metabolic abnormalities, including visceral obesity, dyslipidemia, and insulin resistance. In this regard, visceral white adipose tissue (vWAT) plays a critical role, influencing energy metabolism, immunomodulation, and oxidative stress. Adipose-derived stem cells (ADSCs) are key players in these processes within vWAT. While second-generation antipsychotics (SGAs) have significantly improved treatments for mental health disorders, their chronic use is associated with an increased risk of MetS. In this study, we explored the impact of SGAs on ADSCs to better understand their role in MetS and identify potential therapeutic targets. Our findings reveal that olanzapine disrupts lipid droplet formation during adipogenic differentiation, impairing insulin receptor endocytosis, turnover, and signaling. SGAs also alter the endolysosomal compartment, leading to acidic vesicle accumulation and increased lysosomal biogenesis through TFEB activation. PKCζ is crucial for the SGA-induced nuclear translocation of TFEB and acidic vesicle formation. Notably, inhibiting PKCζ restored insulin receptor tyrosine phosphorylation, normalized receptor turnover, and improved downstream signaling following olanzapine treatment. This activation of PKCζ by olanzapine is driven by increased phosphatidic acid synthesis via phospholipase D (PLD), following G protein-coupled receptor (GPCR) signaling activation. Overall, olanzapine and clozapine disrupt endolysosomal homeostasis and insulin signaling in a PKCζ-dependent manner. These findings highlight SGAs as valuable tools for uncovering cellular dysfunction in vWAT during MetS and may guide the development of new therapeutic strategies to mitigate the metabolic side effects of these drugs.

Impact of steroid therapy on pediatric acute liver failure: prognostic implication and interplay between TNF-α and miR-122

BACKGROUND

Acute liver failure (ALF) is a rare illness marked by rapid deterioration of liver function, leading to high morbidity and mortality rates, particularly in children. While steroids have been observed to correlate with improved survival, evidence supporting their efficacy in ALF children remains limited. miR-122, a liver-specific microRNA, plays a pivotal role in liver pathology, with its expression significantly altered in various liver diseases. Thus, it is considered a potential biomarker for disease progression, aids in prognosis, and identifies therapeutic targets. Our study aims to assess the expression of miR-122 in 24 children with ALF, both before and after steroid therapy, alongside its relationship with tumor necrosis factor-α (TNF-α), to better understand its potential role in treatment response and disease outcomes. miR-122 levels were determined using quantitative real-time RT-PCR (qRT-PCR), while TNF-α levels were assessed using enzyme-linked immunosorbent assay (ELISA) in patient sera.

RESULTS

In ALF children who survived after steroid treatment, miR-122 was markedly decreased compared to both pre-treatment levels (p = 0.003) and levels in deceased patients (p = 0.01). In addition, TNF-α levels significantly increased in surviving patients compared to pre-treatment levels (p = 0.008) and levels in deceased children (p = 0.028). A negative correlation was observed between TNF-α and miR-122 following steroids (r=-0.46, p = 0.04). miR-122 demonstrated 72% sensitivity and 67% specificity in distinguishing survivors and non-survivors, as indicated by its receiver-operated characteristic curve. A positive correlation was found between miR-122 before steroid therapy and both aspartate aminotransferase (AST) and alanine aminotransferase (ALT) before (r = 0.641, p = 0.002 and r = 0.512, p = 0.02, respectively) and after (r = 0.492, p = 0.03 and r = 0.652, p = 0.003, respectively) steroids treatment.

CONCLUSION

Our data implies that lower miR-122 levels in steroids-treated ALF children are associated with a better outcome. Although miR-122 is not a strong standalone marker, it could be valuable in a biomarker panel. The increased TNF-α levels and decreased miR-122 expression indicate their involvement in the disease's pathophysiology. More studies are needed to validate our results.

Normothermic liver perfusion derived extracellular vesicles have concentration-dependent immunoregulatory properties

Extracellular vesicles (EVs) are major contributors to immunological responses following solid organ transplantation. Donor derived EVs are best known for their role in transplant rejection through transferring donor major histocompatibility complex proteins to recipient antigen presenting cells, a phenomenon known as ‛cross-decoration'. In contrast, donor liver-derived EVs are associated with organ tolerance in small animal models. Therefore, the cellular source of EVs and their cargo could influence their downstream immunological effects. To investigate the immunological effects of EVs released by the liver in a physiological and transplant-relevant model, we isolated EVs being produced during normothermic ex vivo liver perfusion (NEVLP), a novel method of liver storage prior to transplantation. We found EVs were produced by the liver during NEVLP, and these EVs contained multiple anti-inflammatory miRNA species. In terms of function, liver-derived EVs were able to cross-decorate allogeneic cells and suppress the immune response in allogeneic mixed lymphocyte reactions in a concentration-dependent fashion. In terms of cytokine response, the addition of 1 × 109 EVs to the mixed lymphocyte reactions significantly decreased the production of the inflammatory cytokines TNF-α, IL-10 and IFN-γ. In conclusion, we determined physiologically produced liver-derived EVs are immunologically regulatory, which has implications for their role and potential modification in solid organ transplantation.

Adipose-derived miRNAs as potential biomarkers for predicting adulthood obesity and its complications: A systematic review and bioinformatic analysis

Adipose tissue is the first and primary target organ of obesity and the main source of circulating miRNAs in patients with obesity. This systematic review aimed to analyze and summarize the generation and mechanisms of adipose-derived miRNAs and their role as early predictors of various obesity-related complications. Literature searches in the PubMed and Web of Science databases using terms related to miRNAs, obesity, and adipose tissue. Pre-miRNAs from the Human MicroRNA Disease Database, known to regulate obesity-related metabolic disorders, were combined for intersection processing. Validated miRNA targets were sorted through literature review, and enrichment analysis using the Kyoto Encyclopedia of Genes and Genomes via the KOBAS online tool, disease analysis, and miRNA transcription factor prediction using the TransmiR v. 2.0 database were also performed. Thirty miRNAs were identified using both obesity and adipose secretion as criteria. Seventy-nine functionally validated targets associated with 30 comorbidities of these miRNAs were identified, implicating pathways such as autophagy, p53 pathways, and inflammation. The miRNA precursors were analyzed to predict their transcription factors and explore their biosynthesis mechanisms. Our findings offer potential insights into the epigenetic changes related to adipose-driven obesity-related comorbidities.

Insulin Resistance in Pediatric Obesity: From Mechanisms to Treatment Strategies

Insulin resistance, an increasingly prevalent characteristic among children and adolescents with obesity, is now recognized as a significant contributor to the development of type 2 diabetes mellitus (T2DM) and other metabolic diseases in individuals with obesity. Insulin resistance refers to a decrease in the sensitivity of peripheral tissues (primarily skeletal muscle, adipose tissue, and liver) to insulin, which is mainly characterized by impaired glucose uptake and utilization. Although the mechanisms underlying insulin resistance in children with obesity remain incompletely elucidated, several risk factors including lipid metabolism disorders, oxidative stress (OS), mitochondrial dysfunction, inflammation, and genetic factors have been identified as pivotal contributors to the pathogenesis of obesity-related insulin resistance. In this review, we comprehensively analyze relevant literature and studies to elucidate the underlying mechanisms of insulin resistance in childhood obesity. Additionally, we discuss treatment strategies for pediatric obesity from a perspective centered on improving insulin sensitivity, aiming to provide valuable insights for the prevention and management of pediatric obesity.

Uncovering essential anesthetics-induced exosomal miRNAs related to hepatocellular carcinoma progression: a bioinformatic investigation

BACKGROUND

Anesthetic drugs may alter exosomal microRNA (miRNA) contents and mediate cancer progression and tumor microenvironment remodeling. Our study aims to explore how the anesthetics (sevoflurane and propofol) impact the miRNA makeup within exosomes in hepatocellular carcinoma (HCC), alongside the interconnected signaling pathways linked to the tumor immune microenvironment.

METHODS

In this prospective study, we collected plasma exosomes from two groups of HCC patients (n = 5 each) treated with either propofol or sevoflurane, both before anesthesia and after hepatectomy. Exosomal miRNA profiles were assessed using next-generation sequencing (NGS). Furthermore, the expression data from The Cancer Genome Atlas-Liver Hepatocellular Carcinoma (TCGA-LIHC) was used to pinpoint the differentially expressed exosomal miRNAs (DEmiRNAs) attributed to the influence of propofol or sevoflurane in the context of HCC. Gene set enrichment analysis (GSEA) and gene set variation analysis (GSVA) were used to dissect the signaling pathways and biological activities associated with the identified DEmiRNAs and their corresponding target genes.

RESULTS

A total of 35 distinct DEmiRNAs were exclusively regulated by either propofol (n = 9) or sevoflurane (n = 26). Through TCGA-LIHC database analysis, 8 DEmiRNAs were associated with HCC. These included propofol-triggered miR-452-5p and let-7c-5p, as well as sevoflurane-induced miR-24-1-5p, miR-122-5p, miR-200a-3p, miR-4686, miR-214-3p, and miR-511-5p. Analyses revealed that among these 8 DEmiRNAs, the upregulation of miR-24-1-5p consistently demonstrated a significant association with lower histological grades (p < 0.0001), early-stage tumors (p < 0.05) and higher survival (p = 0.029). Further analyses using GSEA and GSVA indicated that miR-24-1-5p, along with its target genes, were involved in governing the tumor immune microenvironment and potentially inhibiting tumor progression in HCC.

CONCLUSIONS

This study provided bioinformatics evidence suggesting that sevoflurane-induced plasma exosomal miRNAs may have a potential impact on the immune microenvironment of HCC. These findings established a foundation for future research into mechanistic outcomes in cancer patients.

The Role of a Cholecystokinin Receptor Antagonist in the Management of Chronic Pancreatitis: A Phase 1 Trial

Chronic pancreatitis (CP) is a rare but debilitating condition with an 8-fold increased risk of developing pancreatic cancer. In addition to the symptoms that come from the loss of endocrine and exocrine function in CP, the management of chronic pain is problematic. We previously showed that the CCK-receptor antagonist called proglumide could decrease inflammation, acinar-ductal metaplasia, and fibrosis in murine models of CP. We hypothesized that proglumide would be safe and diminish pain caused by CP. A Phase 1 open-labeled safety study was performed in subjects with clinical and radiographic evidence of CP with moderate to severe pain. After a 4-week observation period, the subjects were treated with proglumide in 400 mg capsules three times daily (1200 mg per day) by mouth for 12 weeks, and then subjects returned for a safety visit 4 weeks after the discontinuation of the study medication. The results of three pain surveys (Numeric Rating Scale, COMPAT-SF, and NIH PROMIS) showed that the patients had significantly less pain after 12 weeks of proglumide compared to the pre-treatment observation phase. Of the eight subjects in this study, two experienced nausea and diarrhea with proglumide. These side effects resolved in one subject with doses reduced to 800 mg per day. No abnormalities were noted in the blood chemistries. A blood microRNA blood biomarker panel that corresponded to pancreatic inflammation and fibrosis showed significant improvement. We conclude that proglumide is safe and well tolerated in most subjects with CP at a dose of 1200 mg per day. Furthermore, proglumide therapy may have a beneficial effect by decreasing pain associated with CP.

Would Combination Be Better: Swimming Exercise and Intermittent Fasting Improve High-Fat Diet-Induced Nonalcoholic Fatty Liver Disease in Obese Rats via the miR-122-5p/SREBP-1c/CPT1A Pathway

Background

Swimming and intermittent fasting can both improve obesity-induced NAFLD, but which of the two is more effective and whether the combination of the two has a superimposed effect is inconclusive.

Methods

The model of NAFLD in obese rats was established by a high-fat diet and performed swimming, intermittent fasting, and a combination of both interventions for 8 weeks. Serum lipids and enzyme activity were measured by an automatic biochemical analyzer. Liver morphostructural analysis was observed by transmission electron microscopy, and morphology was observed by HE staining. RT‒PCR was used to detect the mRNA level.

Results

Morphology and microstructure of the liver of model rats were impaired, with the upregulation of miR-122-5p, SREBP-1c, FASN and ACC1. Eight weeks of swimming exercise, intermittent fasting and the combination of both attenuate these effects, manifested by the downregulation of miR-122-5p and upregulation of CPT1A mRNA levels. There was no significant stacking effect of the combination of the swimming and intermittent fasting interventions.

Conclusion

NAFLD leads to pathology in model rats. Eight weeks of swimming exercise, intermittent fasting and the combination of both can inhibit miR-122-5p and improve hepatic lipid metabolism, while no significant additive effects of combining the interventions were found.

MicroRNAs-associated with FOXO3 in cellular senescence and other stress responses

FOXO3 is a member of the FOXO transcription factor family and is known for regulating cellular survival in response to stress caused by various external and biological stimuli. FOXO3 decides cell fate by modulating cellular senescence, apoptosis and autophagy by transcriptional regulation of genes involved in DNA damage response and oxidative stress resistance. These cellular processes are tightly regulated physiologically, with FOXO3 acting as the hub that integrates signalling networks controlling them. The activity of FOXO3 is influenced by post-translational modifications, altering its subcellular localisation. In addition, FOXO3 can also be regulated directly or indirectly by microRNAs (miRNAs) or vice versa. This review discusses the involvement of various miRNAs in FOXO3-driven cellular responses such as senescence, apoptosis, autophagy, redox and inflammation defence. Given that these responses are linked and influence cell fate, a thorough understanding of the complex regulation by miRNAs would provide key information for developing therapeutic strategy and avoid unintended consequences caused by off-site targeting of FOXO3.

Circulating microRNA expression and nonalcoholic fatty liver disease in adolescents with severe obesity

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases in children and adolescents. NAFLD ranges in severity from isolated hepatic steatosis to nonalcoholic steatohepatitis (NASH), wherein hepatocellular inflammation and/or fibrosis coexist with steatosis. Circulating microRNA (miRNA) levels have been suggested to be altered in NAFLD, but the extent to which miRNA are related to NAFLD features remains unknown. This analysis tested the hypothesis that plasma miRNAs are significantly associated with histological features of NAFLD in adolescents.

AIM

To investigate the relationship between plasma miRNA expression and NAFLD features among adolescents with NAFLD.

METHODS

This study included 81 adolescents diagnosed with NAFLD and 54 adolescents without NAFLD from the Teen-Longitudinal Assessment of Bariatric Surgery study. Intra-operative core liver biopsies were collected from participants and used to characterize histological features of NAFLD. Plasma samples were collected during surgery for miRNA profiling. A total of 843 plasma miRNAs were profiled using the HTG EdgeSeq platform. We examined associations of plasma miRNAs and NAFLD features using logistic regression after adjusting for age, sex, race, and other key covariates. Ingenuity Pathways Analysis was used to identify biological functions of miRNAs that were associated with multiple histological features of NAFLD.

RESULTS

We identified 16 upregulated plasma miRNAs, including miR-193a-5p and miR-193b-5p, and 22 downregulated plasma miRNAs, including miR-1282 and miR-6734-5p, in adolescents with NAFLD. Moreover, 52, 16, 15, and 9 plasma miRNAs were associated with NASH, fibrosis, ballooning degeneration, and lobular inflammation, respectively. Collectively, 16 miRNAs were associated with two or more histological features of NAFLD. Among those miRNAs, miR-411-5p was downregulated in NASH, ballooning, and fibrosis, while miR-122-5p, miR-1343-5p, miR-193a-5p, miR-193b-5p, and miR-7845-5p were consistently and positively associated with all histological features of NAFLD. Pathway analysis revealed that most common pathways of miRNAs associated with multiple NAFLD features have been associated with tumor progression, while we also identified linkages between miR-122-5p and hepatitis C virus and between miR-199b-5p and chronic hepatitis B.

CONCLUSION

Plasma miRNAs were associated with NAFLD features in adolescent with severe obesity. Larger studies with more heterogeneous NAFLD phenotypes are needed to evaluate miRNAs as potential biomarkers of NAFLD.

Circulating miRNA 122-5p Expression Predicts Mortality and Cardiovascular Events in Chronic Hemodialysis Patients: A Multicentric, Pilot, Prospective Study

BACKGROUND

Despite patients undergoing chronic hemodialysis (HD) being notoriously prone to adverse cardiovascular (CV) events, risk prediction in this population remains challenging. miRNA 122-5p, a short, non-coding RNA predominantly involved in lipid and carbohydrate metabolism, has recently been related to the onset and progression of CV disease.

METHODS

We run a pilot, multicenter, longitudinal, observational study to evaluate the clinical significance and prognostic usefulness of circulating miRNA 122-5p in a multicentric cohort of 74 individuals on maintenance HD.

RESULTS

Patients displayed lower circulating miRNA 122-5p as compared to healthy controls (p = 0.004). At correlation analyses, ALT (β = 0.333; p = 0.02), E/e' (β = 0.265; p = 0.02) and CRP (β = -0.219; p = 0.041) were independent predictors of miRNA 122-5p levels. During a median follow-up of 22 months (range of 1-24), 30 subjects (40.5%) experienced a composite endpoint of all-cause mortality and fatal/non-fatal CV events. Baseline circulating miRNA 122-5p was higher in these subjects (p = 0.01) and it predicted a significantly higher risk of endpoint occurrence (Kaplan-Meier crude HR 3.192; 95% CI 1.529-6.663; p = 0.002; Cox regression adjusted HR 1.115; 95% CI 1.009-1.232; p = 0.03).

CONCLUSIONS

Altered miRNA 122-5p levels in HD patients may reflect hepatic and CV damage and may impart important prognostic information for improving CV risk prediction in this particular setting.

The Role of MicroRNAs in Liver Functioning: from Biogenesis to Therapeutic Approaches (Review)

Molecular diagnostics based on small non-coding RNA molecules (in particular microRNA) is a new direction in modern biomedicine and is considered a promising method for identification of a wide range of pathologies at an early stage, clinical phenotype assessment, as well as monitoring the course of the disease, evaluation of therapy efficacy and the risk of the disease recurrence. Currently, the role of microRNAs as the most important epigenetic regulator in cancer development has been proven within the studies of normal and pathogenic processes. However, currently, there are insignificant studies devoted to studying the role of microRNAs in functioning of other organs and tissues, as well as to development of possible therapeutic approaches based on microRNAs. A huge number of metabolic processes in the liver are controlled by microRNAs, which creates enormous potential for the use of microRNAs as a diagnostic marker and makes it a target for therapeutic intervention in metabolic, oncological, and even viral diseases of this organ. This review examines various aspects of biological functions of microRNAs in different types of liver cells. Both canonical and non-canonical pathways of biogenesis, epigenetic regulation mediated by microRNAs, as well as the microRNAs role in intercellular communication and the course of viral diseases are shown. The potential of microRNAs as a diagnostic marker for various liver pathologies is described, as well as therapeutic approaches and medicines based on microRNAs, which are approved for clinical use and currently being developed.

Recent Insights into the Biomarkers, Molecular Targets and Mechanisms of Non-Alcoholic Steatohepatitis-Driven Hepatocarcinogenesis

Non-alcoholic fatty liver disease (NAFLD) or metabolic dysfunction-associated steatotic liver disease (MASLD) and steatohepatitis (NASH) are chronic hepatic conditions leading to hepatocellular carcinoma (HCC) development. According to the recent "multiple-parallel-hits hypothesis", NASH could be caused by abnormal metabolism, accumulation of lipids, mitochondrial dysfunction, and oxidative and endoplasmic reticulum stresses and is found in obese and non-obese patients. Recent translational research studies have discovered new proteins and signaling pathways that are involved not only in the development of NAFLD but also in its progression to NASH, cirrhosis, and HCC. Nevertheless, the mechanisms of HCC developing from precancerous lesions have not yet been fully elucidated. Now, it is of particular importance to start research focusing on the discovery of novel molecular pathways that mediate alterations in glucose and lipid metabolism, which leads to the development of liver steatosis. The role of mTOR signaling in NASH progression to HCC has recently attracted attention. The goals of this review are (1) to highlight recent research on novel genetic and protein contributions to NAFLD/NASH; (2) to investigate how recent scientific findings might outline the process that causes NASH-associated HCC; and (3) to explore the reliable biomarkers/targets of NAFLD/NASH-associated hepatocarcinogenesis.

Targeted MicroRNA Profiling Reveals That Exendin-4 Modulates the Expression of Several MicroRNAs to Reduce Steatosis in HepG2 Cells

Excess hepatic lipid accumulation is the hallmark of non-alcoholic fatty liver disease (NAFLD), for which no medication is currently approved. However, glucagon-like peptide-1 receptor agonists (GLP-1RAs), already approved for treating type 2 diabetes, have lately emerged as possible treatments. Herein we aim to investigate how the GLP-1RA exendin-4 (Ex-4) affects the microRNA (miRNAs) expression profile using an in vitro model of steatosis. Total RNA, including miRNAs, was isolated from control, steatotic, and Ex-4-treated steatotic cells and used for probing a panel of 799 highly curated miRNAs using NanoString technology. Enrichment pathway analysis was used to find the signaling pathways and cellular functions associated with the differentially expressed miRNAs. Our data shows that Ex-4 reversed the expression of a set of miRNAs. Functional enrichment analysis highlighted many relevant signaling pathways and cellular functions enriched in the differentially expressed miRNAs, including hepatic fibrosis, insulin receptor, PPAR, Wnt/β-Catenin, VEGF, and mTOR receptor signaling pathways, fibrosis of the liver, cirrhosis of the liver, proliferation of hepatic stellate cells, diabetes mellitus, glucose metabolism disorder and proliferation of liver cells. Our findings suggest that miRNAs may play essential roles in the processes driving steatosis reduction in response to GLP-1R agonists, which warrants further functional investigation.

Experimental model and novel therapeutic targets for non-alcoholic fatty liver disease development

Non-alcoholic fatty liver disease (NAFLD) is a complex disorder characterized by the accumulation of fat in the liver in the absence of excessive alcohol consumption. It is one of the most common liver diseases worldwide, affecting approximately 25% of the global population. It is closely associated with obesity, type 2 diabetes, and metabolic syndrome. Moreover, NAFLD can progress to non-alcoholic steatohepatitis, which can cause liver cirrhosis, liver failure, and hepatocellular carcinoma. Currently, there are no approved drugs for the treatment of NAFLD. Therefore, the development of effective drugs is essential for NAFLD treatment. In this article, we discuss the experimental models and novel therapeutic targets for NAFLD. Additionally, we propose new strategies for the development of drugs for NAFLD.

Therapeutic Effects of microRNAs on Nonalcoholic Fatty Liver Disease (NAFLD) and Nonalcoholic Steatohepatitis (NASH): A Systematic Review and Meta-Analysis

Nonalcoholic fatty liver disease (NAFLD) has emerged as a global health problem that affects people even at young ages due to unhealthy lifestyles. Without intervention, NAFLD will develop into nonalcoholic steatohepatitis (NASH) and eventually liver cirrhosis and hepatocellular carcinoma. Although lifestyle interventions are therapeutic, effective implementation remains challenging. In the efforts to establish effective treatment for NAFLD/NASH, microRNA (miRNA)-based therapies began to evolve in the last decade. Therefore, this systematic review aims to summarize current knowledge on the promising miRNA-based approaches in NAFLD/NASH therapies. A current systematic evaluation and a meta-analysis were conducted according to the PRISMA statement. In addition, a comprehensive exploration of PubMed, Cochrane, and Scopus databases was conducted to perform article searches. A total of 56 different miRNAs were reported as potential therapeutic agents in these studies. miRNA-34a antagonist/inhibitor was found to be the most studied variant (n = 7), and it significantly improved the hepatic total cholesterol, total triglyceride, Aspartate Aminotransferase (AST), and Alanine Transaminase (ALT) levels based on a meta-analysis. The biological processes mediated by these miRNAs involved hepatic fat accumulation, inflammation, and fibrosis. miRNAs have shown enormous therapeutic potential in the management of NAFLD/NASH, wherein miRNA-34a antagonist has been found to be an exceptional potential agent for the treatment of NAFLD/NASH.

Exosomes and lipid metabolism in metabolic and cardiovascular disorders

PURPOSE OF REVIEW

Exosomes are lipid-bound particles that carry lipids, protein, and nucleic acid and affect cellular function. This review highlights the current knowledge on the crosstalk between exosomes and lipid metabolism and their impact on cardiometabolic disease.

RECENT FINDINGS

Recent studies revealed that lipids and lipid metabolizing enzymes are important for exosome biogenesis and internalization and conversely how exosomes affect lipid metabolism, secretion, and degradation. The interplay between exosomes and lipid metabolism affects disease pathophysiology. More importantly, exosomes and lipids might function as biomarkers for diagnosis and prognosis or possibly therapies.

SUMMARY

Recent advances in our understanding of exosomes and lipid metabolism have implications for our understanding of normal cellular and physiological functions as well as disease pathogenesis. Exosome and lipid metabolism have implications in novel diagnostic tests and treatments of cardiometabolic disease.

Association between Circulating MicroRNAs (miR-21-5p, miR-20a-5p, miR-29b-3p, miR-126-3p and miR-101-3p) and Chronic Allograft Dysfunction in Renal Transplant Recipients

Chronic allograft dysfunction (CAD) is a major condition affecting long-term kidney graft survival. Serum microRNA (miRNA) has been reported as a biomarker for various conditions of allograft injuries. The upregulation of miR-21 is the best-known miRNA change in graft tissue, urine and plasma. However, the correlation of plasma miR-21 with the severity of CAD remains unclear. In our study, 40 kidney transplantation recipients with late graft survival for more than 10 years were enrolled. The CAD group (n = 20) had either an eGFR between 15 to 60 mL/min or a biopsy-proved chronic allograft nephropathy or rejection. The control group (n = 20) had an eGFR ≥ 60 mL/min without proteinuria and hematuria for a consecutive 3 months before the study. We performed RNA sequencing to profile the miRNAs expression. There were six differentially expressed miRNAs in the CAD group. Among them, miR-21-5p and miR-101-3p were decreased, and miR-20a-5p was increased. We found that miR-21-5p, miR-20a-5p and miR-101-3p all participated in the TGF-beta pathway. We demonstrated that decreased miR-21-5p and miR-101-3p, and increased miR-20a-5p were the novel CAD-associated miRNAs in the TGF-beta pathway. These findings may pave the way for developing early prediction miRNAs biomarkers for CAD, and possibly developing therapeutic tools in the field of kidney transplantation.

Molecular Targets and Signaling Pathways of microRNA-122 in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading global causes of cancer mortality. MicroRNAs (miRNAs) are small interfering RNAs that alleviate the levels of protein expression by suppressing translation, inducing mRNA cleavage, and promoting mRNA degradation. miR-122 is the most abundant miRNA in the liver and is responsible for several liver-specific functions, including metabolism, cellular growth and differentiation, and hepatitis virus replication. Recent studies have shown that aberrant regulation of miR-122 is a key factor contributing to the development of HCC. In this review, the signaling pathways and the molecular targets of miR-122 involved in the progression of HCC have been summarized, and the importance of miR-122 in therapy has been discussed.

Western diet-induced shifts in the maternal microbiome are associated with altered microRNA expression in baboon placenta and fetal liver

Maternal consumption of a high-fat, Western-style diet (WD) disrupts the maternal/infant microbiome and contributes to developmental programming of the immune system and nonalcoholic fatty liver disease (NAFLD) in the offspring. Epigenetic changes, including non-coding miRNAs in the fetus and/or placenta may also underlie this risk. We previously showed that obese nonhuman primates fed a WD during pregnancy results in the loss of beneficial maternal gut microbes and dysregulation of cellular metabolism and mitochondrial dysfunction in the fetal liver, leading to a perturbed postnatal immune response with accelerated NAFLD in juvenile offspring. Here, we investigated associations between WD-induced maternal metabolic and microbiome changes, in the absence of obesity, and miRNA and gene expression changes in the placenta and fetal liver. After ~8-11 months of WD feeding, dams were similar in body weight but exhibited mild, systemic inflammation (elevated CRP and neutrophil count) and dyslipidemia (increased triglycerides and cholesterol) compared with dams fed a control diet. The maternal gut microbiome was mainly comprised of Lactobacillales and Clostridiales, with significantly decreased alpha diversity (P = 0.0163) in WD-fed dams but no community-wide differences (P = 0.26). At 0.9 gestation, mRNA expression of IL6 and TNF in maternal WD (mWD) exposed placentas trended higher, while increased triglycerides, expression of pro-inflammatory CCR2, and histological evidence for fibrosis were found in mWD-exposed fetal livers. In the mWD-exposed fetus, hepatic expression levels of miR-204-5p and miR-145-3p were significantly downregulated, whereas in mWD-exposed placentas, miR-182-5p and miR-183-5p were significantly decreased. Notably, miR-1285-3p expression in the liver and miR-183-5p in the placenta were significantly associated with inflammation and lipid synthesis pathway genes, respectively. Blautia and Ruminococcus were significantly associated with miR-122-5p in liver, while Coriobacteriaceae and Prevotellaceae were strongly associated with miR-1285-3p in the placenta; both miRNAs are implicated in pathways mediating postnatal growth and obesity. Our findings demonstrate that mWD shifts the maternal microbiome, lipid metabolism, and inflammation prior to obesity and are associated with epigenetic changes in the placenta and fetal liver. These changes may underlie inflammation, oxidative stress, and fibrosis patterns that drive NAFLD and metabolic disease risk in the next generation.