Serum miR-379 expression is related to the development and progression of hypercholesterolemia in non-alcoholic fatty liver disease

Biomarkers for Health Functional Foods in Metabolic Dysfunction-Associated Steatotic Liver Disorder (MASLD) Prevention: An Integrative Analysis of Network Pharmacology, Gut Microbiota, and Multi-Omics

Metabolic dysfunction-associated steatotic liver disorder (MASLD) is increasingly prevalent globally, highlighting the need for preventive strategies and early interventions. This comprehensive review explores the potential of health functional foods (HFFs) to maintain healthy liver function and prevent MASLD through an integrative analysis of network pharmacology, gut microbiota, and multi-omics approaches. We first examined the biomarkers associated with MASLD, emphasizing the complex interplay of genetic, environmental, and lifestyle factors. We then applied network pharmacology to identify food components with potential beneficial effects on liver health and metabolic function, elucidating their action mechanisms. This review identifies and evaluates strategies for halting or reversing the development of steatotic liver disease in the early stages, as well as biomarkers that can evaluate the success or failure of such strategies. The crucial role of the gut microbiota and its metabolites for MASLD prevention and metabolic homeostasis is discussed. We also cover state-of-the-art omics approaches, including transcriptomics, metabolomics, and integrated multi-omics analyses, in research on preventing MASLD. These advanced technologies provide deeper insights into physiological mechanisms and potential biomarkers for HFF development. The review concludes by proposing an integrated approach for developing HFFs targeting MASLD prevention, considering the Korean regulatory framework. We outline future research directions that bridge the gap between basic science and practical applications in health functional food development. This narrative review provides a foundation for researchers and food industry professionals interested in developing HFFs to support liver health. Emphasis is placed on maintaining metabolic balance and focusing on prevention and early-stage intervention strategies.

Molecular Insights of Nonalcoholic Fatty Liver Disease Pathogenesis

Nonalcoholic fatty liver disease (NAFLD) is now the most prevalent chronic liver disease. Many hepatic abnormalities are associated with NAFLD such as nonalcoholic steatohepatitis, progressive fibrosis, cirrhosis, and liver failure. Moreover, the pathogenesis of NAFLD has numerous etiologies and can be explained due to the existence of several of stimulus that act simultaneously on genetically susceptible patients. These stimuli include obesity, diabetes, and insulin resistance. In addition, identifying the role of gut microbiota on NAFLD progression has been illustrated. In this review, we clarified the several factors that lead to the development of NAFLD and identify those who are most at risk of developing liver end-stage disease. Highlighting the noninvasive diagnostic NAFLD markers could be helpful in the disease prevention and treatment approaches.

MicroRNAs and Nonalcoholic Steatohepatitis: A Review

Non-alcoholic fatty liver disease (NAFLD) is a clinicopathologic syndrome caused by fat deposition in hepatocytes. Patients with nonalcoholic steatohepatitis (NASH), an advanced form of NAFLD with severe fibrosis, are at high risk for liver-related complications, including hepatocellular carcinoma (HCC). However, the mechanism of progression from simple fat deposition to NASH is complex, and previous reports have linked NAFLD to gut microbiota, bile acids, immunity, adipokines, oxidative stress, and genetic or epigenetic factors. NASH-related liver injury involves multiple cell types, and intercellular signaling is thought to be mediated by extracellular vesicles. MicroRNAs (miRNAs) are short, noncoding RNAs that play important roles as post-transcriptional regulators of gene expression and have been implicated in the pathogenesis of various diseases. Recently, many reports have implicated microRNAs in the pathogenesis of NALFD/NASH, suggesting that exosomal miRNAs are potential non-invasive and sensitive biomarkers and that the microRNAs involved in the mechanism of the progression of NASH may be potential therapeutic target molecules. We are interested in which miRNAs are involved in the pathogenesis of NASH and which are potential target molecules for therapy. We summarize targeted miRNAs associated with the etiology and progression of NASH and discuss each miRNA in terms of its pathophysiology, potential therapeutic applications, and efficacy as a NASH biomarker.

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.

miR-379 mediates insulin resistance and obesity through impaired angiogenesis and adipogenesis regulated by ER stress

We investigated the role of microRNA (miR-379) in the pathogenesis of obesity, adipose tissue dysfunction, and insulin resistance (IR). We used miR-379 knockout (miR-379KO) mice to test whether loss of miR-379 affects high-fat diet (HFD)-induced obesity and IR via dysregulation of key miR-379 targets in adipose tissue. Increases in body weight, hyperinsulinemia, and IR in wild-type (WT)-HFD mice were significantly attenuated in miR-379KO-HFD mice with some sex differences. Relative to control chow-fed mice, in WT-HFD mice, expression of miR-379 and C/EBP homologous protein (Chop) (pro-endoplasmic reticulum [ER] stress) and inflammation in perigonadal white adipose tissue (gWAT) were increased, whereas adipogenic genes and miR-379 target genes (Vegfb and Edem3) were decreased. These changes, as well as key parameters of brown adipose tissue dysfunction (including mitochondrial defects), were significantly attenuated in miR-379KO-HFD mice. WAT from obese human subjects with and without type 2 diabetes showed increased miR-379 and decreased miR-379 target genes. In cultured 3T3L1 pre-adipocytes, miR-379 inhibitors increased miR-379 targets and adipogenic genes. These data suggest that miR-379 plays an important role in HFD-induced obesity through increased adipose inflammation, mitochondrial dysfunction, and ER stress as well as impaired adipogenesis and angiogenesis. miR-379 inhibitors may be developed as novel therapies for obesity and associated complications.

Role of miR-379 in high-fat diet-induced kidney injury and dysfunction

Obesity is associated with increased risk for diabetes and damage to the kidneys. Evidence suggests that miR-379 plays a role in the pathogenesis of diabetic kidney disease. However, its involvement in obesity-induced kidney injury is not known and was therefore investigated in this study by comparing renal phenotypes of high-fat diet (HFD)-fed wild-type (WT) and miR-379 knockout (KO) mice. Male and female WT mice on the HFD for 10 or 24 wk developed obesity, hyperinsulinemia, and kidney dysfunction manifested by albuminuria and glomerular injuries. However, these adverse alterations in HFD-fed WT mice were significantly ameliorated in HFD-fed miR-379 KO mice. HFD feeding increased glomerular expression of miR-379 and decreased its target gene, endoplasmic reticulum (ER) degradation enhancing α-mannosidase-like protein 3 (Edem3), a negative regulator of ER stress. Relative to the standard chow diet-fed controls, expression of profibrotic transforming growth factor-β1 (Tgf-β1) was significantly increased, whereas Zeb2, which encodes ZEB2, a negative regulator of Tgf-β1, was decreased in the glomeruli in HFD-fed WT mice. Notably, these changes as well as HFD-induced increased expression of other profibrotic genes, glomerular hypertrophy, and interstitial fibrosis in HFD-fed WT mice were attenuated in HFD-fed miR-379 KO mice. In cultured primary glomerular mouse mesangial cells (MMCs) isolated from WT mice, treatment with high insulin (mimicking hyperinsulinemia) increased miR-379 expression and decreased its target, Edem3. Moreover, insulin also upregulated Tgf-β1 and downregulated Zeb2 in WT MMCs, but these changes were significantly attenuated in MMCs from miR-379 KO mice. Together, these experiments revealed that miR-379 deletion protects mice from HFD- and hyperinsulinemia-induced kidney injury at least in part through reduced ER stress.NEW & NOTEWORTHY miR-379 knockout mice are protected from high-fat diet (HFD)-induced kidney damage through key miR-379 targets associated with ER stress (Edem3). Mechanistically, treatment of mesangial cells with insulin (mimicking hyperinsulinemia) increased expression of miR-379, Tgf-β1, miR-200, and Chop and decreases Edem3. Furthermore, TGF-β1-induced fibrotic genes are attenuated by a GapmeR targeting miR-379. The results implicate a miR-379/EDEM3/ER stress/miR-200c/Zeb2 signaling pathway in HFD/obesity/insulin resistance-induced renal dysfunction. Targeting miR-379 with GapmeRs can aid in the treatment of obesity-induced kidney disease.

Investigating microRNAs to Explain the Link between Cholesterol Metabolism and NAFLD in Humans: A Systematic Review

Non-Alcoholic Fatty Liver Disease (NAFLD) is characterized by hepatic free cholesterol accumulation. In addition, microRNAs (miRNAs) might be involved in NAFLD development. Therefore, we systematically reviewed the literature to examine the link between miRNAs and cholesterol metabolism in NAFLD. Nineteen studies were retrieved by a systematic search in September 2022. From these papers, we evaluated associations between 13 miRNAs with NAFLD and cholesterol metabolism. Additionally, their diagnostic potential was examined. Four miRNAs (miR122, 34a, 132 and 21) were associated with cholesterol metabolism and markers for NAFLD. MiR122 was upregulated in serum of NAFLD patients, increased with disease severity and correlated with HDL-C, TAG, VLDL-C, AST, ALT, ALP, lobular inflammation, hepatocellular ballooning and NAFLD score. Serum and hepatic levels also correlated. Serum and hepatic miR34a levels were increased in NAFLD, and correlated with VLDL-C and TAG. Serum miR379 was also higher in NAFLD, especially in early stages, while miR21 gave ambiguous results. The diagnostic properties of these miRNAs were comparable to those of existing biomarkers. However, serum miR122 levels appeared to be elevated before increases in ALT and AST were evident. In conclusion, miR122, miR34a, miR21 and miR132 may play a role in the development of NAFLD via effects on cholesterol metabolism. Furthermore, it needs to be explored if miRNAs 122, 34a and 379 could be used as part of a panel in addition to established biomarkers in early detection of NAFLD.

MicroRNA-379-5p regulates free cholesterol accumulation and relieves diet induced-liver damage in db/db mice via STAT1/HMGCS1 axis

Lipotoxicity induced by the overload of lipid in the liver, especially excess free cholesterol (FC), has been recognized as one of driving factors in the transition from non-alcoholic fatty liver (NAFL) to non-alcoholic steatohepatitis (NASH). MicroRNA (miR)-379-5p has been reported to play regulatory roles in hepatic triglyceride homeostasis, but the relationship of miR-379-5p and hepatic cholesterol homeostasis has never been touched. In the current study, we found that hepatic miR-379-5p levels were decreased obviously in NAFLD patients and model mice compared with their controls. Moreover, miR-379-5p was discovered to be able to inhibit intracellular FC accumulation and alleviate mitochondrial damage induced by palmitic acid (PA) in vitro. Furthermore, overexpression of miR-379-5p in HFHC-fed db/db mice could reduce the level of hepatic total cholesterol (TC) and FC, and ameliorate hepatic injury reflected by the lower serum alanine aminotransferase (ALT) and aspartate transaminase (AST). Subsequently, by combining spectrometry (MS) and luciferase assay, we identified miR-379-5p suppressed STAT1 through transcriptional and translational regulation. Finally, we confirmed that STAT1 was a transcriptional factor of HMGCS1. In conclusion, miR-379-5p inhibits STAT1 expression and regulates cholesterol metabolism through the STAT1/HMGCS1 axis, suggesting miR-379-5p might be applied to improve lipotoxicity in the future.

An Update in Epigenetics in Metabolic-Associated Fatty Liver Disease

Metabolic-associated fatty liver disease (MAFLD) is characterized by hepatic steatosis accompanied by one of three features: overweight or obesity, T2DM, or lean or normal weight with evidence of metabolic dysregulation. It is distinguished by excessive fat accumulation in hepatocytes, and a decrease in the liver's ability to oxidize fats, the accumulation of ectopic fat, and the activation of proinflammatory pathways. Chronic damage will keep this pathophysiologic cycle active causing progression from hepatic steatosis to cirrhosis and eventually, hepatocarcinoma. Epigenetics affecting gene expression without altering DNA sequence allows us to study MAFLD pathophysiology from a different perspective, in which DNA methylation processes, histone modifications, and miRNAs expression have been closely associated with MAFLD progression. However, these considerations also faced us with the circumstance that modifying those epigenetics patterns might lead to MAFLD regression. Currently, epigenetics is an area of great interest because it could provide new insights in therapeutic targets and non-invasive biomarkers. This review comprises an update on the role of epigenetic patterns, as well as innovative therapeutic targets and biomarkers in MAFLD.

Therapeutic perspectives of extracellular vesicles and extracellular microRNAs in atherosclerosis

Extracellular signaling molecules, such as growth factors, cytokines, and hormones, regulate cell behaviors and fate through endocrine, paracrine, and autocrine actions and play essential roles in maintaining tissue homeostasis. MicroRNAs, an important class of posttranscriptional modulators, could stably present in extracellular space and body fluids and participate in intercellular communication in health and diseases. Indeed, recent studies demonstrated that microRNAs could be secreted through vesicular and non-vesicular routes, transported in body fluids, and then transmitted to recipient cells to regulate target gene expression and signaling events. Over the past decade, a great deal of effort has been made to investigate the functional roles of extracellular vesicles and extracellular microRNAs in pathological conditions. Emerging evidence suggests that altered levels of extracellular vesicles and extracellular microRNAs in body fluids, as part of the cellular responses to atherogenic factors, are associated with the development of atherosclerosis. This review article provides a brief overview of extracellular vesicles and perspectives of their applications as therapeutic tools for cardiovascular pathologies. In addition, we highlight the role of extracellular microRNAs in atherogenesis and offer a summary of circulating microRNAs in liquid biopsies associated with atherosclerosis.

Analysis of miRNAs Profiles in Serum of Patients With Steatosis and Steatohepatitis

Non-alcoholic fatty liver disease (NAFLD) is emerging as one of the most common chronic liver diseases worldwide, affecting 25% of the world population. In recent years, there has been increasing evidence for the involvement of microRNAs in the epigenetic regulation of genes taking part in the development of steatosis and steatohepatitis—two main stages of NAFLD pathogenesis. In the present study, miRNA profiles were studied in groups of patients with steatosis and steatohepatitis to compare the characteristics of RNA-dependent epigenetic regulation of the stages of NAFLD development. According to the results of miRNA screening, 23 miRNAs were differentially expressed serum in a group of patients with steatohepatitis and 2 in a group of patients with steatosis. MiR-195-5p and miR-16-5p are common differentially expressed miRNAs for both steatosis and steatohepatitis. We analyzed the obtained results: the search for target genes for the differentially expressed miRNAs in our study and the subsequent gene set enrichment analysis performed on KEGG and REACTOME databases revealed which metabolic pathways undergo changes in RNA-dependent epigenetic regulation in steatosis and steatohepatitis. New findings within the framework of this study are the dysregulation of neurohumoral pathways in the pathogenesis of NAFLD as an object of changes in RNA-dependent epigenetic regulation. The miRNAs differentially expressed in our study were found to target 7% of genes in the classic pathogenesis of NAFLD in the group of patients with steatosis and 50% in the group of patients with steatohepatitis. The effects of these microRNAs on genes for the pathogenesis of NAFLD were analyzed in detail. MiR-374a-5p, miR-1-3p and miR-23a-3p do not target genes directly involved in the pathogenesis of NAFLD. The differentially expressed miRNAs found in this study target genes largely responsible for mitochondrial function. The role of miR-423-5p, miR-143-5p and miR-200c-3 in regulating apoptotic processes in the liver and hepatocarcinogenesis is of interest for future experimental studies. These miR-374a, miR-143, miR-1, miR-23a, and miR-423 have potential for steatohepatitis diagnosis and are poorly studied in the context of NAFLD. Thus, this work opens up prospects for further studies of microRNAs as diagnostic and therapeutic biomarkers for NAFLD.

Lack of miR-379/miR-544 Cluster Resists High-Fat Diet-Induced Obesity and Prevents Hepatic Triglyceride Accumulation in Mice

Non-alcoholic fatty liver disease (NAFLD) affects obesity-associated metabolic syndrome, which exhibits hepatic steatosis, insulin insensitivity and glucose intolerance. Emerging evidence suggests that microRNAs (miRNAs) are essential for the metabolic homeostasis of liver tissues. Many hepatic miRNAs located in the miR-379/miR-544 cluster were significantly increased in leptin-receptor-deficient type 2 mice (db/db), a mouse model of diabetes. However, the function of the miR-379/miR-544 cluster in the process of hepatic steatosis remains unclear. Here, we report that the novel function of miR-379/miR-544 cluster in regulating obesity-mediated metabolic dysfunction. Genetical mutation of miR-379/miR-544 cluster in mice displayed resistance to high-fat diet (HFD)-induced obesity with moderate hepatic steatosis and hypertriglyceridemia. In vitro studies revealed that silencing of miR-379 in human hepatocellular carcinoma (HepG2) cells ameliorated palmitic acid-induced elevation of cellular triglycerides, and overexpression of miR-379 had the opposite effect. Moreover, Igf1r (Insulin-like growth factor 1 receptor) and Dlk1 (Delta-like homolog 1) were directly targeted by miR-379 and miR-329, respectively, and elevated in the livers of the miR-379/miR-544 cluster knockout mice fed on HFD. Further transcriptome analyses revealed that the hepatic gene expressions are dysregulated in miR-379/miR-544 knockout mice fed with HFD. Collectively, our findings identify the miR-379/miR-544 cluster as integral components of a regulatory circuit that functions under conditions of metabolic stress to control hepatic steatosis. Thus, this miRNA cluster provides potential targets for pharmacologic intervention in obesity and NAFLD.

MiR-145-5p modulates lipid metabolism and M2 macrophage polarization by targeting PAK7 and regulating β-catenin signaling in hyperlipidemia

The present study aims to explore the role of microRNA 145-5p (miR-145-5p) in hyperlipidemia. Using bioinformatics tools and a wide range of function and mechanism assays, we attempted to understand the specific function and potential mechanism of miR-145-5p in hyperlipidemia. A cholesterol-enriched diet induced an increase of serum cholesterol and triacylglycerol but a decrease of serum high-density lipoprotein. MiR-145-5p level was decreased in hyperlipidemia rat models. MiR-145-5p regulated lipid metabolism by antagonizing the alteration of high-density lipoprotein, cholesterol, and triacylglycerol in serum mediated by a cholesterol-enriched diet. In mechanism, miR-145-5p directly bound with p21 protein (RAC1)-activated kinase 7 (PAK7) and negatively regulated mRNA and protein levels of PAK7 in THP-1 cells. Furthermore, miR-145-5p level was negatively associated with PAK7 level in rat cardiac tissues. Finally, overexpression of PAK7 reversed the effects of miR-145-5p on β-catenin activation and M2 macrophages polarization in THP-1 cells. In conclusion, MiR-145-5p modulated lipid metabolism and M2 macrophage polarization by targeting PAK7 and regulating β-catenin signaling in hyperlipidemia, which may provide a potential biomarker for the treatment of hyperlipidemia-induced cardiovascular diseases.

An update on the role of miR-379 in human disorders

miR-379 is a miRNA transcribed from the MIR379 locus on 14q32.31. This miRNA is located in an evolutionarily conserved miRNA cluster in an imprinted region that contains DLK1 and DIO3 genes. The mouse homolog of this miRNA has been shown to be under-expressed in response to glucocorticoid receptor deficiency. Moreover, miR-379 has a tumor-suppressive role in a wide variety of tissues including the brain, breast, lung, and liver. In addition to restraining cell proliferation and migration, miR-379 can suppress the epithelial-mesenchymal transition process. Abnormal expression of this miRNA implies the pathogenesis of Duchene muscular dystrophy, spinal cord injury, diabetic nephropathy, acute myocardial infarction, and premature ovarian failure. This review aims to the summarization of the role of miR-379 in neoplastic and non-neoplastic conditions.

High miR-324-5p expression predicts unfavorable prognosis of gastric cancer and facilitates tumor progression in tumor cells

Background

Gastric cancer (GCa) is one of the six major malignancies in the world with low survival rate. Although there are advances in therapeutic approaches, the prognosis of patients with GCa remains not optimistic. Therefore, this study aimed to evaluate the prognostic value of miR-324-5p, as well as its functional role in GCa progression.

Methods

The expression of miR-324-5p in tumor tissues and cell lines was examined using real-time quantitative PCR. The prognostic value of miR-324-5p in patients with GCa was evaluated by Kaplan-Meier survival curve and Cox regression analysis. Gain- and loss-of-function experiments were performed to evaluate the biological function of miR-324-5p during the progression of GCa, and a target gene of miR-324-5p was proposed.

Results

The expression of miR-324-5p was up-regulated in GCa tissues and cell lines. Patients with high expression of miR-324-5p had more cases with positive lymph node metastasis, advanced TNM stage, and worse overall survival compared with patients with low expression. The elevated miR-324-5p was an independent prognostic indicator of GCa. In addition, the inhibition of miR-324-5p could suppress GCa cell proliferation, migration and invasion and promote cell apoptosis, and PTEN was demonstrated to serve as a direct target of miR-324-5p in GCa progression.

Conclusion

The present study indicates that miR-324-5p overexpression predicts poor prognosis in GCa patients, and the reduction of miR-324-5p can inhibit GCa biological processes. PTEN is a target gene of GCa, which may mediate the biological function of miR-324-5p in GCa progression.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13000-020-01063-2.

Impact of Long-Term Supplementation with Fish Oil in Individuals with Non-Alcoholic Fatty Liver Disease: A Double Blind Randomized Placebo Controlled Clinical Trial

Non-alcoholic fatty liver disease (NAFLD) is a chronic disease affecting up to 25% of the population worldwide. n-3 long-chain polyunsaturated fatty acids (n-3 PUFA) have been associated with improved clinical parameters of NAFLD. Our purpose was to conduct a pilot study to evaluate the effects of n-3 PUFA supplementation in a randomized, double-blind, placebo-controlled clinical study performed on NAFLD individuals diagnosed by ultrasound. Patients received n-3 PUFA (n = 13) or placebo (n = 11) supplementation for six months. Circulating miR-122 expression (determined by quantitative real time-polymerase chain reaction (qRT-PCR), liver fibrosis (FibroScan^®), red blood cells (RBC) fatty acids (gas chromatography), and biochemical tests were performed at baseline and after intervention. After the intervention, in the n-3 PUFA group, docosahexaenoic acid (DHA) and omega index increased significantly in RBC (p = 0.022 and p = 0.012, respectively), in addition to a significant reduction in alkaline phosphatase (ALP) (p = 0.002) and liver fibrosis (p = 0.039). However, there was no change in the expression of circulating miR-122 in both groups. Our results showed that omega-3 PUFA were incorporated in erythrocytes after six months of fish oil supplementary intake, and that n-3 PUFA were effective in reducing ALP and liver fibrosis without altering the expression of circulating miR-122 in individuals with NAFLD.

The Role of microRNAs in Metabolic Syndrome-Related Oxidative Stress

Oxidative stress (OxS) is the cause and the consequence of metabolic syndrome (MetS), the incidence and economic burden of which is increasing each year. OxS triggers the dysregulation of signaling pathways associated with metabolism and epigenetics, including microRNAs, which are biomarkers of metabolic disorders. In this review, we aimed to summarize the current knowledge regarding the interplay between microRNAs and OxS in MetS and its components. We searched PubMed and Google Scholar to summarize the most relevant studies. Collected data suggested that different sources of OxS (e.g., hyperglycemia, insulin resistance (IR), hyperlipidemia, obesity, proinflammatory cytokines) change the expression of numerous microRNAs in organs involved in the regulation of glucose and lipid metabolism and endothelium. Dysregulated microRNAs either directly or indirectly affect the expression and/or activity of molecules of antioxidative signaling pathways (SIRT1, FOXOs, Keap1/Nrf2) along with effector enzymes (e.g., GPx-1, SOD1/2, HO-1), ROS producers (e.g., NOX4/5), as well as genes of numerous signaling pathways connected with inflammation, insulin sensitivity, and lipid metabolism, thus promoting the progression of metabolic imbalance. MicroRNAs appear to be important epigenetic modifiers in managing the delicate redox balance, mediating either pro- or antioxidant biological impacts. Summarizing, microRNAs may be promising therapeutic targets in ameliorating the repercussions of OxS in MetS.

Estimation of the post-mortem interval using microRNA in the bones

MicroRNAs (miRNAs) can be useful in forensic science because of their numerous characteristics, especially stability. Post-mortem interval (PMI) is crucial for death scene investigations. However, estimating PMI is challenging in cases involving significantly decomposed or destroyed bodies, such as those involving skeletonized remains. In this study, 71 bones (patella) were collected from the bodies during autopsies (PMI ranging from 1 day to 2 years). As the let-7e and miR-16 miRNAs were used as internal controls for the bone tissue in previous studies, these miRNAs were selected as targets to estimate PMI. The miRNA Ce_miR-39_1 was used as a spike-in internal control to normalize the target miRNA levels. Real-time quantitative reverse transcription polymerase chain reaction was performed to correlate the expression levels of let-7e and miR-16 with increasing PMI. A negative correlation was observed between miRNA expression and increasing PMI. The expression of both let-7e and miR-16 was observed to be significantly different between group A and the other PMI groups (group A < 1 month; 1 month < group B < 3 months; 3 months < group C < 6 months; group D > 6 months). In conclusion, these data suggest that the expression level of specific miRNAs (let-7e and miR-16) in the bone tissue could be used to estimate PMI. However, more studies using long-term PMI samples are required to further corroborate these findings.