Energizing miRNA research: a review of the role of miRNAs in lipid metabolism, with a prediction that miR-103/107 regulates human metabolic pathways

PIEZO1 as a new target for hyperglycemic stress-induced neuropathic injury: The potential therapeutic role of bezafibrate

Hyperglycemic stress can directly lead to neuronal damage. The mechanosensitive ion channel PIEZO1 can be activated in response to hyperglycemia, but its role in hyperglycemic neurotoxicity is unclear. The role of PIEZO1 in hyperglycemic neurotoxicity was explored by constructing a hyperglycemic mouse model and a high-glucose HT22 cell model. The results showed that PIEZO1 was significantly upregulated in response to high glucose stress. In vitro experiments have shown that high glucose stress induces changes in neuronal cell morphology and membrane tension, a key mechanism for PIEZO1 activation. In addition, high glucose stress upregulates serum/glucocorticoid-regulated kinase-1 (SGK1) and activates PIEZO1 through the Ca2+ pool and store-operated calcium entry (SOCE). PIEZO1-mediated Ca2+ influx further enhances SGK1 and SOCE, inducing intracellular Ca2+ peaks in neurons. PIEZO1 mediated intracellular Ca2+ elevation leads to calcium/calmodulin-dependent protein kinase 2α (CaMK2α) overactivation, which promotes oxidative stress and apoptosis signalling through p-CaMK2α/ERK/CREB and ox-CaMK2α/MAPK p38/NFκB p65 pathways, subsequently inducing synaptic damage and cognitive impairment in mice. The intron miR-107 of pantothenic kinase 1 (PANK1) is highly expressed in the brain and has been found to target PIEZO1 and SGK1. The PANK1 receptor is activated by peroxisome proliferator-activated receptor α (PPARα), an activator known to upregulate miR-107 levels in the brain. The clinically used lipid-lowering drug bezafibrate, a known PPARα activator, may upregulate miR-107 through the PPARɑ/PANK1 pathway, thereby inhibiting PIEZO1 and improving hyperglycemia-induced neuronal cell damage. This study provides a new idea for the pathogenesis and drug treatment of hyperglycemic neurotoxicity and diabetes-related cognitive dysfunction.

Oligonucleotide therapies for nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH) represents a severe disease subtype of nonalcoholic fatty liver disease (NAFLD) that is thought to be highly associated with systemic metabolic abnormalities. It is characterized by a series of substantial liver damage, including hepatocellular steatosis, inflammation, and fibrosis. The end stage of NASH, in some cases, may result in cirrhosis and hepatocellular carcinoma (HCC). Nowadays a large number of investigations are actively under way to test various therapeutic strategies, including emerging oligonucleotide drugs (e.g., antisense oligonucleotide, small interfering RNA, microRNA, mimic/inhibitor RNA, and small activating RNA) that have shown high potential in treating this fatal liver disease. This article systematically reviews the pathogenesis of NASH/NAFLD, the promising druggable targets proven by current studies in chemical compounds or biological drug development, and the feasibility and limitations of oligonucleotide-based therapeutic approaches under clinical or pre-clinical studies.

Deciphering adipose development: Function, differentiation and regulation

The overdevelopment of adipose tissues, accompanied by excess lipid accumulation and energy storage, leads to adipose deposition and obesity. With the increasing incidence of obesity in recent years, obesity is becoming a major risk factor for human health, causing various relevant diseases (including hypertension, diabetes, osteoarthritis and cancers). Therefore, it is of significance to antagonize obesity to reduce the risk of obesity-related diseases. Excess lipid accumulation in adipose tissues is mediated by adipocyte hypertrophy (expansion of pre-existing adipocytes) or hyperplasia (increase of newly-formed adipocytes). It is necessary to prevent excessive accumulation of adipose tissues by controlling adipose development. Adipogenesis is exquisitely regulated by many factors in vivo and in vitro, including hormones, cytokines, gender and dietary components. The present review has concluded a comprehensive understanding of adipose development including its origin, classification, distribution, function, differentiation and molecular mechanisms underlying adipogenesis, which may provide potential therapeutic strategies for harnessing obesity without impairing adipose tissue function.

Exploring transcriptional and post-transcriptional epigenetic regulation of crf and 11βhsd2 in rainbow trout brain during chronic social stress

Using dominance hierarchies in juvenile rainbow trout (Oncorhynchus mykiss) as a model of chronic social stress in fish, we explored whether epigenetic transcriptional and post-transcriptional mechanisms are involved in the gene expression of corticotropin-releasing factor (crf) and 11β-hydroxysteroid dehydrogenase (11βhsd2), key factors involved in the regulation of the endocrine stress axis response. In juvenile rainbow trout pairs, subordinate individuals display sustained elevation of circulating cortisol concentrations. Cortisol production is controlled by the hypothalamic-pituitary-interrenal (HPI) axis in fish and initiated by CRF release from the preoptic area (POA). Given that crf is modulated during chronic social stress, and that such stress has been implicated in the epigenetic regulation of crf in other taxa, we probed a role for epigenetic regulation of crf transcript abundance in chronically stressed rainbow trout. We also investigated the regulation of the cortisol-metabolising enzyme 11βhsd2 in the POA, which is upregulated in subordinates. The potential involvement of DNA methylation and microRNAs (miRNAs) in the regulation of crf transcript abundance was investigated during social stress in the POA of fish, as was the potential involvement of miRNAs in 11βhsd2 regulation. Although transcript abundances of crf were elevated in subordinate fish after 4 days, DNA methylation profiles within putative promoter sequences upstream of the crf gene were not significantly affected by chronic stress. An inverse relationship between crf and its predicted posttranscriptional regulator miR-103a-3p in the POA suggests that miRNAs may be involved in mediating the effects of chronic social stress on key components of the endocrine stress axis.

Extracellular vesicles and exosome-like nanovesicles as pioneering oral drug delivery systems

As extracellular vesicle (EV)-based nanotechnology has developed rapidly, it has made unprecedented opportunities for nanomedicine possible. EVs and exosome-like nanovesicles (ELNVs) are natural nanocarriers with unique structural, compositional, and morphological characteristics that provide excellent physical, chemical, and biochemical properties. In this literature, we examine the characteristics of EVs, including how they are administered orally and their therapeutic activity. According to the current examples of EVs and ELNVs for oral delivery, milk and plant EVs can exert therapeutic effects through their protein, nucleic acid, and lipid components. Furthermore, several methods for loading drugs into exosomes and targeting exosomes have been employed to investigate their therapeutic capability. Moreover, we discuss EVs as potential drug carriers and the potential role of ELNVs for disease prevention and treatment or as potential drug carriers in the future. In conclusion, the issues associated with the development of EVs and ELNVs from sources such as milk and plants, as well as concerns with standardized applications of these EVs, are discussed.

MicroRNAs in infectious diseases: potential diagnostic biomarkers and therapeutic targets

MicroRNAs (miRNAs) are conserved, short, non-coding RNAs that play a crucial role in the post-transcriptional regulation of gene expression. They have been implicated in the pathogenesis of cancer and neurological, cardiovascular, and autoimmune diseases. Several recent studies have suggested that miRNAs are key players in regulating the differentiation, maturation, and activation of immune cells, thereby influencing the host immune response to infection. The resultant upregulation or downregulation of miRNAs from infection influences the protein expression of genes responsible for the immune response and can determine the risk of disease progression. Recently, miRNAs have been explored as diagnostic biomarkers and therapeutic targets in various infectious diseases. This review summarizes our current understanding of the role of miRNAs during viral, fungal, bacterial, and parasitic infections from a clinical perspective, including critical functional mechanisms and implications for their potential use as biomarkers and therapeutic targets.

MiRNA dysregulation underlying common pathways in type 2 diabetes and cancer development: an Italian Association of Medical Oncology (AIOM)/Italian Association of Medical Diabetologists (AMD)/Italian Society of Diabetology (SID)/Italian Society of Endocrinology (SIE)/Italian Society of Pharmacology (SIF) multidisciplinary critical view

Increasing evidence suggests that patients with diabetes, particularly type 2 diabetes (T2D), are characterized by an increased risk of developing different types of cancer, so cancer could be proposed as a new T2D-related complication. On the other hand, cancer may also increase the risk of developing new-onset diabetes, mainly caused by anticancer therapies. Hyperinsulinemia, hyperglycemia, and chronic inflammation typical of T2D could represent possible mechanisms involved in cancer development in diabetic patients. MicroRNAs (miRNAs) are a subset of non-coding RNAs, ⁓22 nucleotides in length, which control the post-transcriptional regulation of gene expression through both translational repression and messenger RNA degradation. Of note, miRNAs have multiple target genes and alteration of their expression has been reported in multiple diseases, including T2D and cancer. Accordingly, specific miRNA-regulated pathways are involved in the pathogenesis of both conditions. In this review, a panel of experts from the Italian Association of Medical Oncology (AIOM), Italian Association of Medical Diabetologists (AMD), Italian Society of Diabetology (SID), Italian Society of Endocrinology (SIE), and Italian Society of Pharmacology (SIF) provide a critical view of the evidence about the involvement of miRNAs in the pathophysiology of both T2D and cancer, trying to identify the shared miRNA signature and pathways able to explain the strong correlation between the two conditions, as well as to envision new common pharmacological approaches.

Deciphering the RNA-binding protein interaction with the mRNAs encoded from human chromosome 15q11.2 BP1-BP2 microdeletion region

Microdeletion of the 15q11.2 BP1-BP2 region, also known as Burnside-Butler susceptibility region, is associated with phenotypes like delayed developmental language abilities along with motor skill disabilities, combined with behavioral and emotional problems. The 15q11.2 microdeletion region harbors four evolutionarily conserved and non-imprinted protein-coding genes: NIPA1, NIPA2, CYFIP1, and TUBGCP5. This microdeletion is a rare copy number variation frequently associated with several pathogenic conditions in humans. The aim of this study is to investigate the RNA-binding proteins binding with the four genes present in 15q11.2 BP1-BP2 microdeletion region. The results of this study will help to better understand the molecular intricacies of the Burnside-Butler Syndrome and also the possible involvement of these interactions in the disease aetiology. Our results of enhanced crosslinking and immunoprecipitation data analysis indicate that most of the RBPs interacting with the 15q11.2 region are involved in the post-transcriptional regulation of the concerned genes. The RBPs binding to this region are found from the in silico analysis, and the interaction of RBPs like FASTKD2 and EFTUD2 with exon-intron junction sequence of CYFIP1 and TUBGCP5 has also been validated by combined EMSA and western blotting experiment. The exon-intron junction binding nature of these proteins suggests their potential involvement in splicing process. This study may help to understand the intricate relationship of RBPs with mRNAs within this region, along with their functional significance in normal development, and lack thereof, in neurodevelopmental disorders. This understanding will help in the formulation of better therapeutic approaches.

Uncovering key molecules and immune landscape in cholestatic liver injury: implications for pathogenesis and drug therapy

Background: Cholestasis is a common pathological process in a variety of liver diseases that may lead to liver fibrosis, cirrhosis, and even liver failure. Cholestasis relief has been regarded as a principal target in the management of multiple chronic cholestasis liver diseases like primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC) at present. However, complicated pathogenesis and limited acknowledgments fettered therapeutic development. Therefore, this study aimed to systematically analyze miRNA-mRNA regulatory networks in cholestatic liver injury in order to provide new treatment strategies. Methods: Gene Expression Omnibus (GEO) database (GSE159676) was used to screen differentially expressed hepatic miRNAs and mRNAs in the PSC vs. control comparison and the PBC vs. control comparison, respectively. MiRWalk 2.0 tool was used to predict miRNA-mRNA pairs. Subsequently, functional analysis and immune cell infiltration analysis were performed to explore the pivotal functions of the target genes. RT-PCR was used to verify the result. Results: In total, a miRNA-mRNA network including 6 miRNAs (miR-122, miR-30e, let-7c, miR-107, miR-503, and miR-192) and 8 hub genes (PTPRC, TYROBP, LCP2, RAC2, SYK, TLR2, CD53, and LAPTM5) was constructed in cholestasis. Functional analysis revealed that these genes were mainly involved in the regulation of the immune system. Further analysis revealed that resting memory CD4 T cells and monocytes could potentially participate in cholestatic liver injury. The expressions of DEMis and eight hub genes were verified in ANIT-induced and BDL-induced cholestatic mouse models. Furthermore, SYK was found to have an impact on the response to UDCA, and its mechanism was possibly associated with complement activation and monocyte reduction. Conclusion: In the present study, a miRNA-mRNA regulatory network was constructed in cholestatic liver injury, which mostly mediated immune-related pathways. Moreover, the targeted gene SYK and monocytes were found to be related to UDCA response in PBC.

Functional importance of glucose transporters and chromatin epigenetic factors in Glioblastoma Multiforme (GBM): possible therapeutics

Glioblastoma Multiforme (GBM) is an aggressive brain cancer affecting glial cells and is chemo- and radio-resistant. Glucose is considered the most vital energy source for cancer cell proliferation. During metabolism, hexose molecules will be transported into the cells via transmembrane proteins known as glucose transporter (GLUT). Among them, GLUT-1 and GLUT-3 play pivotal roles in glucose transport in GBM. Knockdown studies have established the role of GLUT-1, and GLUT-3 mediated glucose transport in GBM cells, providing insight into GLUT-mediated cancer signaling and cancer aggressiveness. This review focussed on the vital role of GLUT-1 and GLUT-3 proteins, which regulate glucose transport. Recent studies have identified the role of GLUT inhibitors in effective cancer prevention. Several of them are in clinical trials. Understanding and functional approaches towards glucose-mediated cell metabolism and chromatin epigenetics will provide valuable insights into the mechanism of cancer aggressiveness, cancer stemness, and chemo-resistance in Glioblastoma Multiforme (GBM). This review summarizes the role of GLUT inhibitors, micro-RNAs, and long non-coding RNAs that aid in inhibiting glucose uptake by the GBM cells and other cancer cells leading to the identification of potential therapeutic, prognostic as well as diagnostic markers. Furthermore, the involvement of epigenetic factors, such as microRNAs, in regulating glycolytic genes was demonstrated.

microRNA-103a-3p promotes inflammation and fibrosis in nonalcoholic fatty liver disease by targeting HBP1

BACKGROUND

As a metabolic-associated disease, nonalcoholic fatty liver disease (NAFLD) development is tightly linked to lipid accumulation, inflammatory response, and fibrosis. Our study was intended to expound the role of microRNA (miR)-103a-3p in the pathogenesis of NAFLD.

METHODS

First, potentially relevant genes in NAFLD were screened using microarray analysis. The expression of lipid metabolism-related, inflammatory, and liver fibrosis indicators in the serum of patients with NAFLD was analyzed. We established a NAFLD mouse model and analyzed the serum level of lipid metabolism- and inflammation-related factors and fibrosis in the liver tissues of NAFLD mice. The targeting relationship between miR-103a-3p and HBP1 was examined by dual-luciferase reporter gene assay, RT-qPCR, and Western blot. Finally, the simultaneous effects of miR-103a-3p and HBP1 knockdown on lipid metabolism, inflammatory response, and liver fibrosis in NAFLD mice were analyzed by rescue experiments.

RESULTS

MiR-103a-3p was upregulated in the serum of NAFLD patients and liver tissues of NAFLD mice, with increased lipid accumulation, inflammation, and liver fibrosis. HBP1 was reduced in liver tissues of NAFLD mice, and miR-103a-3p bound to and negatively regulated HBP1. Inhibition of miR-103a-3p or promotion of HBP1 improved liver function, decreased lipid accumulation, suppressed inflammatory response, and reduced liver fibrosis in NAFLD mice. Moreover, sh-HBP1 partially reversed the effect of miR-103a-3p inhibitor on NAFLD mice, leading to increased lipid accumulation, elevated inflammation, and fibrosis in the liver of mice.

CONCLUSIONS

miR-103a-3p inhibits the expression of HBP1, thus suppressing lipid metabolism, stimulating inflammatory responses, and promoting liver fibrosis in NAFLD.

MicroRNAs as Regulators of Cancer Cell Energy Metabolism

To adapt to the tumor environment or to escape chemotherapy, cancer cells rapidly reprogram their metabolism. The hallmark biochemical phenotype of cancer cells is the shift in metabolic reprogramming towards aerobic glycolysis. It was thought that this metabolic shift to glycolysis alone was sufficient for cancer cells to meet their heightened energy and metabolic demands for proliferation and survival. Recent studies, however, show that cancer cells rely on glutamine, lipid, and mitochondrial metabolism for energy. Oncogenes and scavenging pathways control many of these metabolic changes, and several metabolic and tumorigenic pathways are post-transcriptionally regulated by microRNA (miRNAs). Genes that are directly or indirectly responsible for energy production in cells are either negatively or positively regulated by miRNAs. Therefore, some miRNAs play an oncogenic role by regulating the metabolic shift that occurs in cancer cells. Additionally, miRNAs can regulate mitochondrial calcium stores and energy metabolism, thus promoting cancer cell survival, cell growth, and metastasis. In the electron transport chain (ETC), miRNAs enhance the activity of apoptosis-inducing factor (AIF) and cytochrome c, and these apoptosome proteins are directed towards the ETC rather than to the apoptotic pathway. This review will highlight how miRNAs regulate the enzymes, signaling pathways, and transcription factors of cancer cell metabolism and mitochondrial calcium import/export pathways. The review will also focus on the metabolic reprogramming of cancer cells to promote survival, proliferation, growth, and metastasis with an emphasis on the therapeutic potential of miRNAs for cancer treatment.

Dietary Grape Seed Proanthocyanidin Alleviates the Liver Injury Induced by Long-Term High-Fat Diets in Sprague Dawley Rats

In mammals, the liver is the most important organ that plays a vital function in lipid metabolism. Grape seed proanthocyanidin (GSPE) is a kind of natural polyphenolic compound primarily obtained from grape skin and seeds. Recent research found it had high bioavailability in defending against obesity, hyperlipidemia, inflammatory, oxidative stress, and targeting liver tissue. However, the mechanism of GSPE in regulating obesity induced by dietary high-fat (HF) was not fully understood, particularly the influences on liver functions. Therefore, this study aimed to investigate the effects of GSPE supplementation on the liver function and lipid metabolic parameters in rats fed HF diets long-term. A total of 40 healthy female Sprague Dawley rats were selected. After 8 weeks of obesity model feeding, the rats were randomly divided into four treatments: NC, standard diet; NC + GSPE, standard diet + 500 mg/kg body weight GSPE; HF, high-fat diet; HG + GSPE, high fat diet + 500 mg/kg body weight GSPE. Results indicated that long-term HF feeding caused severe liver problems including megalohepatia, steatosis, inflammation, and hepatocyte apoptosis. The supplementation of GSPE alleviated these symptoms. The results of the current experiment confirmed that GSPE addition up-regulated the expression of the Wnt3a/β-catenin signaling pathway, thereby restraining the liver cell endoplasmic reticulum stress and hepatocyte apoptosis. Furthermore, the microRNA-103 may play a role in this signal-regulated pathway. In summary, GSPE had a protective effect on the liver and the current experiment provided a reference for the application of GSPE in animal nutrition as a kind of natural feed additive.

miRNA-mRNA associations with inosine monophosphate specific deposition in the muscle of Jingyuan chicken

1. Inosine monophosphate (IMP), is an essential component for meat flavour and microRNAs (miRNAs) play a vital role in its post-transcriptional regulation. However, the mechanism of how miRNA expression affects muscle-specific IMP deposition is unclear.2. The following study performed transcriptome sequencing and bioinformatics analysis of breast and leg muscle, which have significantly different IMP content in Jingyuan chicken. The differential miRNA-mRNAs were screened out and correlation analysis with IMP content was performed.3. A total of 39 differentially expressed miRNAs (DE miRNAs) and 666 differentially expressed mRNAs (DE mRNAs) were identified between breast muscles and leg muscles. Using miRNA-mRNA integrated analysis, 29 miRNA-target gene pairs were obtained, composed of 13 DE miRNAs and 28 DE mRNAs. Next, purine metabolism, glycolysis/gluconeogenesis, pyruvate metabolism and the biosynthesis of amino acid pathways as necessary for muscle IMP-specific deposition were identified. The differentially expressed gene PKM2, which was significantly enriched in all four pathways, is involved in IMP anabolism in the form of energy metabolism and enzyme activity regulation. The correlation analysis suggested that the gga-miR-107-3p-KLHDC2 negative interaction may be a key regulator in IMP deposition.4. This study explores the functional mechanism of IMP-specific deposition in Jingyuan chicken muscles at the miRNA and mRNA levels and highlights multiple candidate miRNAs and mRNAs for molecular-assisted breeding.

Deciphering the Molecular Mechanism of Incurable Muscle Disease by a Novel Method for the Interpretation of miRNA Dysregulation

It is now well-established that microRNA dysregulation is a hallmark of human diseases, and that aberrant expression of miRNA is not randomly associated with human pathologies but plays a causal role in the pathological process. Investigations of the molecular mechanism that links miRNA dysregulation to pathophysiology can therefore further the understanding of human diseases. The biological effect of miRNA is thought to be mediated principally by miRNA target genes. Consequently, the target genes of dysregulated miRNA serve as a proxy for the biological interpretation of miRNA dysregulation, which is performed by target gene pathway enrichment analysis. However, this method unfortunately often fails to provide testable hypotheses concerning disease mechanisms. In this paper, we describe a method for the interpretation of miRNA dysregulation, which is based on miRNA host genes rather than target genes. Using this approach, we have recently identified the perturbations of lipid metabolism, and cholesterol in particular, in Duchenne muscular dystrophy (DMD). The host gene-based interpretation of miRNA dysregulation therefore represents an attractive alternative method for the biological interpretation of miRNA dysregulation.

Structure-Activity Relationships of Anti-microRNA Oligonucleotides Containing Cationic Guanidine-Modified Nucleic Acids

Anti-microRNA oligonucleotides (AMOs) are valuable tools for the treatment of diseases caused by the dysregulation of microRNA expression. However, the correlation between chemical modifications in AMO sequences and the microRNA-inhibitory activity has not been fully elucidated. In this study, we synthesized a series of AMOs containing cationic guanidine-bridged nucleic acids (GuNA) and evaluated their activities using a dual luciferase assay. We also optimized the site of GuNA substitution and found an effective design for the inhibition of microRNA-21, which was partially different from that of conventional nucleic acid derivatives. This study showed that GuNA-substituted AMOs are effective in inhibiting the function of microRNA.

Relationship between mir-126 expression in children with psoriasis, disease progression and therapeutic response

This study aimed to investigate the expression level of miR-126 in children with psoriasis in the epidermis affected by psoriasis and intact buccal epithelium, establish the impact on the characteristics of the course of psoriasis and the results of therapy in children with psoriasis of initial expression levels of miR-126. miR-126 expression levels in psoriatic keratinocytes and buccal epithelium were determined in 54 children with psoriasis on the severity of psoriasis, treatment efficacy. miR-126 levels in the buccal epithelium in children with psoriasis were reduced compared to healthy children (AUC=0.776±0.048, p<0.001). There were no discrepancies between miR-126 expression levels in psoriatic keratinocytes and buccal epithelium (p=0.097). There are statistically significant discrepancies between miR-126 expression levels in the psoriatic epidermis depending on the clinical form of psoriasis (AUC=0.637±0.056; p=0.014) and severity according to BSA (AUC=0.634±0.063; p=0.034). Depending on the miR-126 level in the buccal epithelium, the response to treatment (PASI<75) in children with high miR-126 is worse than in children with expected miR-126 levels (OR 2.79; 95%; CI: 1.19 - 6.51). Treatment failures were observed in children with high levels of miR-126 in the buccal epithelium compared to miR-126 in the psoriatic epidermis: children aged 12/13 to 17 years (OR 2.44; 95% CI: 1.02 - 5.85), children with PGA=4 (OR 3.16; 95% CI: 1.34 - 7.43). The location and level of miR-126 expression affects the course of psoriasis and the outcome of treatment. High levels of miR-126 in psoriatic keratinocytes lead to manifestations of plaque psoriasis with a course of moderate to severe forms. Initial miR-126 levels in the buccal epithelium in children with psoriasis are a prognostic criterion for response to therapy and can be used as a marker for prescribing systemic treatment.

Comprehensive miRNA and DNA Microarray Analyses Reveal the Response of Hepatic miR-203 and Its Target Gene to Protein Malnutrition in Rats

Adequate protein nutrition is essential for good health. Effects of protein malnutrition in animals have been widely studied at the mRNA level with the development of DNA microarray technology. Although microRNAs (miRNAs) have attracted attention for their function in regulating gene expression and have been studied in several disciplines, fewer studies have clarified the effects of protein malnutrition on miRNA alterations. The present study aimed to elucidate the relationship between protein malnutrition and miRNAs. Six-week old Wistar male rats were fed a control diet (20% casein) or a low-protein diet (5% casein) for two weeks, and their livers were subjected to both DNA microarray and miRNA array analysis. miR-203 was downregulated and its putative target Hadhb (hydroxyacyl-CoA dehydrogenase β subunit), known to regulate β-oxidation of fatty acids, was upregulated by the low-protein diet. In an in vitro experiment, miR-203 or its inhibitor were transfected in HepG2 cells, and the pattern of Hadhb expression was opposite to that of miR-203 expression. In addition, to clarifying the hepatic miRNA profile in response to protein malnutrition, these results showed that a low-protein diet increased Hadhb expression through downregulation of miR-203 and induced β-oxidation of fatty acids.

Evaluation of muscle-specific and metabolism regulating microRNAs in a chronic swimming rat model

Making benefit from the epigenetic effects of environmental factors such as physical activity may result in a considerable improvement in the prevention of chronic civilization diseases. In our chronic swimming rat model, the expression levels of such microRNAs were characterized, that are involved in skeletal muscle differentiation, hypertrophy and fine-tuning of metabolism, which processes are influenced by chronic endurance training, contributing to the metabolic adaptation of skeletal muscle during physical activity. After chronic swimming, the level of miR-128a increased significantly in EDL muscles, which may influence metabolic adaptation and stress response as well. In SOL, the expression level of miR-15b and miR-451 decreased significantly after chronic swimming, which changes are opposite to their previously described increment in insulin resistant skeletal muscle. MiR-451 also targets PGC-1α mRNA, whiches expression level significantly increased in SOL muscles, resulting in enhanced biogenesis and oxidative capacity of mitochondria. In summary, the microRNA expression changes that were observed during our experiments suggest that chronic swim training contributes to a beneficial metabolic profile of skeletal muscle.

MicroRNAs: From Junk RNA to Life Regulators and Their Role in Cardiovascular Disease

MicroRNAs (miRNAs) are single-stranded small non-coding RNA (18–25 nucleotides) that until a few years ago were considered junk RNA. In the last twenty years, they have acquired more importance thanks to the understanding of their influence on gene expression and their role as negative regulators at post-transcriptional level, influencing the stability of messenger RNA (mRNA). Approximately 5% of the genome encodes miRNAs which are responsible for regulating numerous signaling pathways, cellular processes and cell-to-cell communication. In the cardiovascular system, miRNAs control the functions of various cells, such as cardiomyocytes, endothelial cells, smooth muscle cells and fibroblasts, playing a role in physiological and pathological processes and seeming also related to variations in contractility and hereditary cardiomyopathies. They provide a new perspective on the pathophysiology of disorders such as hypertrophy, fibrosis, arrhythmia, inflammation and atherosclerosis. MiRNAs are differentially expressed in diseased tissue and can be released into the circulation and then detected. MiRNAs have become interesting for the development of new diagnostic and therapeutic tools for various diseases, including heart disease. In this review, the concept of miRNAs and their role in cardiomyopathies will be introduced, focusing on their potential as therapeutic and diagnostic targets (as biomarkers).

Gene Expression of miRNAs Let-7aAssociated with Diabetes in Iraqi Population

miRNAs regulate protein abundance and control diverse aspects of cellular processes and biological functions in metabolic diseases, such as obesity and diabetes. Lethal-7(Let-7) miRNAs specifically target genes associated with diabetes and have a role in the regulation of peripheral glucose metabolism. The present study aimed to describe the gene expressions of the let-7a gene with the development of diabetes in Iraq and the difference in the expression of this gene in patients with diabetes and healthy individuals. The association between age and gender with the development of diabetes was studied in this study and the results were compared with those of healthy individuals in the group of control. Based on the obtained results, there was a lack in the mean of gene expression level (ΔCt) in patients, compared to controls. Moreover, the gene expression folding (2-∆∆Ct) of the let-7a reflects significant differences in terms of gene expression between groups of patients and controls, and the level of let-7a expression was reported to be 12.97 in patients with diabetes. On the other hand, significant difference was observed in terms of age and gender between diabetic patients and controls. The findings suggest that diabetes can affect individuals in all age groups and occur regardless of gender in both males and females. Based on the obtained results in this study, the gene expression level of miRNA let-7a was lower in diabetic patients compared to healthy individuals in the group of control. This also reflects differences in the gene expression fold (2-∆∆Ct) of gene let-7a between both groups of patients and controls.

Effects of neonatal exposure to methoxychlor on corpus luteum in gilts: A transcriptomic analysis

This study investigated the effects of neonatal exposure to methoxychlor (MXC), a synthetic organochlorine used as an insecticide with estrogenic, antiestrogenic, and antiandrogenic activities, on luteal function in pigs. Piglets were injected subcutaneously with MXC (20 μg/kg body weight) or corn oil (control) between postnatal Days 1 and 10 (N = 5/group). Corpora lutea from sexually mature gilts were examined for luteal steroid and prostaglandin concentrations and processed for total RNA isolation and subsequent RNA sequencing. Intra-luteal concentrations of androstenedione and prostaglandin E₂ were greater, while that of estrone was lower when compared to control. Fifty-three differentially expressed (DE) microRNAS (miRNAs) (p-adjusted <.05 and log2(fold change) ≥.5) and 359 DE genes (p-adjusted <.05 and log2(fold change) ≥1) were identified in luteal tissue in response to neonatal MXC treatment. MXC was found to affect the expression of genes related to lipogenesis, steroidogenesis, membrane transport, immune response, cell signaling and adhesion. These results suggest an earlier onset of structural luteolysis in pigs caused by MXC actions in neonates. Since negative correlation analysis showed the potential interactions of miRNAs with specific messenger RNAs, we propose that these miRNAs are potential mediators of the long-term MXC effect on the CL function in pigs.

Benzyl Butyl Phthalate Induced Early lncRNA H19 Regulation in C3H10T1/2 Stem Cell Line

Exposure to endocrine-disrupting chemicals used in plastic manufacturing may contribute to the current obesity and diabetes epidemic. Our previous study demonstrated that benzyl butyl phthalate (BBP) induced adipogenesis in the C3H10T1/2 stem cell line. Here we investigated if BBP deregulated long noncoding RNA H19 and its downstream pathway and whether BBP plays a role in the insulin signaling pathway during adipocyte diiferentiation. Cells treated with an 8 day BBP regimen showed that H19 expression was decreased at day 2 with 50 μM BBP exposure (p < 0.05). However, no significant changes were observed from day 4 to day 8. Expression of miRNA-103/107, H19 regulated miRNAs, was upregulated at day 2 (p < 0.05) but not from day 4 to day 8. Similarly, expression of the let-7 family members (a, b, c, d, f, and g) was also significantly increased at day 2 (p < 0.05 or p < 0.01), except for let-7e. Both let-7 and miRNA-103/107 are targets of H19 and play roles in insulin signaling. Insulin receptor substrate (IRS)-1, one of the key insulin signal transduction regulators, was significantly downregulated from day 2 to day 8 (p < 0.05). Gene expression of insulin receptor (IR) and IRS-2 were not altered by BBP exposure. The ratio of IRS1/IRS2 was significantly decreased from day 2 to day 8. On day 4, phospho-Akt protein expression was significantly decreased (p < 0.05). In conclusion, BBP exposure may lead to metabolic dysregulation by altering vital epigenetic regulators such as lncRNA H19 and its target microRNAs at an earlier stage, which further regulates insulin signaling.

A narrative review of the roles of the miR-15/107 family in heart disease: lessons and prospects for heart disease

Heart disease is one of the leading causes of morbidity and mortality globally. To reduce morbidity and mortality among patients with heart disease, it is important to identify drug targets and biomarkers for more effective diagnosis, prognosis, and treatment. MicroRNAs (miRNAs) are characterized as a group of endogenous, small non-coding RNAs, which function by directly inhibiting target genes. The miR-15/107 family is a group of evolutionarily conserved miRNAs comprising 10 members that share an identical motif of AGCAGC, which determines overlapping target genes and cooperation in the biological process. Accumulating evidence has demonstrated the predominant dysregulation of the miR-15/107 family in cardiovascular disease, neurodegenerative disease, and cancer. In this review, we summarize the current understanding of the miR-15/107 family, focusing on its role in the regulation in the development of the heart and the progression of heart disease. We also discuss the potential of different members of the miR-15/107 family as biomarkers for diverse heart disease, as well as the current applications and challenges in the use of the miR-15/107 family in clinical trials for various disease. This paper hopes to explore the potential of the miR-15/107 family as therapeutic targets or biomarkers and to provide directions for future research.

The pivotal role of MicroRNAs in glucose metabolism in cancer

Cancer cells are able to undergo aerobic glycolysis and metabolize glucose to lactate instead of oxidative phosphorylation, which is known as Warburg effect. Accumulating evidence has revealed that microRNAs regulate cancer cell metabolism, which manifest a higher rate of glucose metabolism. Various signaling pathways along with glycolytic enzymes are responsible for the emergence of glycolytic dependence. MicroRNAs are a class of non-coding RNAs that are not translated into proteins but regulate target gene expression or in other words function pre-translationally and post-transcriptionally. MicroRNAs have been shown to be involved in various biological processes, including glucose metabolism via targeting major transcription factors, enzymes, oncogenes or tumor suppressors alongside the oncogenic signaling pathways. In this review, we describe the regulatory role of microRNAs of cancer cell glucose metabolism, including in the glucose uptake, glycolysis, tricarboxylic acid cycle and several signaling pathways and further suggest that microRNA-based therapeutics can be used to inhibit the process of glucose metabolism reprogramming in cancer cells and thus suppressing cancer progression.

Regulatory microRNAs in Brown, Brite and White Adipose Tissue

MicroRNAs (miRNAs) constitute a class of short noncoding RNAs which regulate gene expression by targeting messenger RNA, inducing translational repression and messenger RNA degradation. This regulation of gene expression by miRNAs in adipose tissue (AT) can impact on the regulation of metabolism and energy homeostasis, particularly considering the different types of adipocytes which exist in mammals, i.e., white adipocytes (white AT; WAT), brown adipocytes (brown AT; BAT), and inducible brown adipocytes in WAT (beige or brite or brown-in-white adipocytes). Indeed, an increasing number of miRNAs has been identified to regulate key signaling pathways of adipogenesis in BAT, brite AT, and WAT by acting on transcription factors that promote or inhibit adipocyte differentiation. For example, MiR-328, MiR-378, MiR-30b/c, MiR-455, MiR-32, and MiR-193b-365 activate brown adipogenesis, whereas MiR-34a, MiR-133, MiR-155, and MiR-27b are brown adipogenesis inhibitors. Given that WAT mainly stores energy as lipids, whilst BAT mainly dissipates energy as heat, clarifying the effects of miRNAs in different types of AT has recently attracted significant research interest, aiming to also develop novel miRNA-based therapies against obesity, diabetes, and other obesity-related diseases. Therefore, this review presents an up-to-date comprehensive overview of the role of key regulatory miRNAs in BAT, brite AT, and WAT.

Cholesterol homeostasis: Researching a dialogue between the brain and peripheral tissues

Cholesterol homeostasis is a highly regulated process in human body because of its several functions underlying the biology of cell membranes, the synthesis of all steroid hormones and bile acids and the need of trafficking lipids destined to cell metabolism. In particular, it has been recognized that peripheral and central nervous system cholesterol metabolism are separated by the blood brain barrier and are regulated independently; indeed, peripherally, it depends on the balance between dietary intake and hepatic synthesis on one hand and its degradation on the other, whereas in central nervous system it is synthetized de novo to ensure brain physiology. In view of this complex metabolism and its relevant functions in mammalian, impaired levels of cholesterol can induce severe cellular dysfunction leading to metabolic, cardiovascular and neurodegenerative diseases. The aim of this review is to clarify the role of cholesterol homeostasis in health and disease highlighting new intriguing aspects of the cross talk between its central and peripheral metabolism.

Interleukin-1β Triggers p53-Mediated Downmodulation of CCR5 and HIV-1 Entry in Macrophages through MicroRNAs 103 and 107

Macrophages are a target of human immunodeficiency virus type 1 (HIV-1) and may serve as a viral reservoir during antiretroviral therapy (ART). Their susceptibility to HIV-1 infection is subject to variations from permissiveness to resistance depending on their origin, tissue localization, and polarization profile. This is in part due to the expression of regulatory microRNAs. Here, we identify two microRNA paralogs, microRNA 103 (miR-103) and miR-107, as regulators of CCR5 expression that are upregulated in noninfected bystander cells of HIV-1-infected-monocyte-derived macrophage (MDM) cultures. Transfection of microRNA 103 mimics in MDMs reduced CCR5 expression levels and inhibited CCR5-dependent HIV-1 entry, whereas the corresponding antagomirs enhanced virus spread in HIV-infected MDMs. Treatment of MDMs with interleukin-1β (IL-1β) enhanced microRNA 103 expression, a condition that we found contributed to the reduction of CCR5 mRNA in IL-1β-exposed MDMs. Interestingly, we show that the induction of miR-103/107 expression is part of a tumor suppressor p53 response triggered by secreted IL-1β that renders macrophages refractory to HIV-1 entry. In a more physiological context, the levels of microRNAs 103 and 107 were found enriched in tissue-resident colon macrophages of healthy donors and alveolar macrophages of individuals under antiretroviral therapy, conceivably contributing to their relative resistance to HIV-1 infection. Overall, these findings highlight the role of p53 in enforcing proinflammatory antiviral responses in macrophages, at least in part, through miR-103/107-mediated downmodulation of CCR5 expression and HIV-1 entry.IMPORTANCE Macrophages are heterogeneous immune cells that display varying susceptibilities to HIV-1 infection, in part due to the expression of small noncoding microRNAs involved in the posttranscriptional regulation of gene expression and silencing. Here, we identify microRNAs 103 and 107 as important p53-regulated effectors of the antiviral response triggered by the proinflammatory cytokine IL-1β in macrophages. These microRNAs, which are enriched in colon macrophages of healthy donors and alveolar macrophages of HIV-infected individuals under antiretroviral therapy, act as inhibitors of HIV-1 entry through their capacity to downregulate the CCR5 coreceptor. These results highlight the important role played by miR-103/107 in modulating CCR5 expression and HIV-1 entry in macrophages. They further underscore a distinct function of the tumor suppressor p53 in enforcing proinflammatory antiviral responses in macrophages, thus providing insight into a cellular pathway that could be targeted to limit the establishment of viral reservoirs in these cells.

Recent Progress on Relevant microRNAs in Autism Spectrum Disorders

Autism spectrum disorder (ASD) is a neurodevelopmental disorder whose pathogenesis is unclear and is affected by both genetic and environmental factors. The microRNAs (miRNAs) are a kind of single-stranded non-coding RNA with 20-22 nucleotides, which normally inhibit their target mRNAs at a post-transcriptional level. miRNAs are involved in almost all biological processes and are closely related to ASD and many other diseases. In this review, we summarize relevant miRNAs in ASD, and analyze dysregulated miRNAs in brain tissues and body fluids of ASD patients, which may contribute to the pathogenesis and diagnosis of ASD.

Identifying host microRNAs in bronchoalveolar lavage samples from lung transplant recipients infected with Aspergillus

BACKGROUND

MicroRNAs (miRNAs) are small non-coding RNAs of ∼22 nucleotides that play a crucial role in post-transcriptional regulation of gene expression. Dysregulation of miRNA expression has been shown during microbial infections. We sought to identify miRNAs that distinguish invasive aspergillosis (IA) from non-IA in lung transplant recipients (LTRs).

METHODS

We used NanoString nCounter Human miRNA, version 3, panel to measure miRNAs in bronchoalveolar lavage (BAL) samples from LTRs with Aspergillus colonization (ASP group) (n = 10), those with Aspergillus colonization and chronic lung allograft dysfunction (CLAD) (ASPCLAD group) (n = 7), those with IA without CLAD (IA group) (n = 10), those who developed IA with CLAD (IACLAD group) (n = 9), and control patients (controls) (n = 9). The miRNA profile was compared using the permutation test of 100,000 trials for each of the comparisons. We used mirDIP to obtain their gene targets and pathDIP to determine the pathway enrichment.

RESULTS

We performed pairwise comparisons between patient groups to identify differentially expressed miRNAs. A total of 5 miRNAs were found to be specific to IA, including 4 (miR-145-5p, miR-424-5p, miR-99b-5p, and miR-4488) that were upregulated and the pair (miR-4454 + miR-7975) that was downregulated in IA group vs controls. The expression change for these miRNAs was specific to patients with IA; they were not significantly differentiated between IACLAD and IA groups. Signaling pathways associated with an immunologic response to IA were found to be significantly enriched.

CONCLUSIONS

We report a set of 5 differentially expressed miRNAs in the BAL of LTRs with IA that might help in the development of diagnostic and prognostic tools for IA in LTRs. However, further investigation is needed in a larger cohort to validate the findings.

Decreased microRNA 103 and microRNA 107 predict increased risks of acute respiratory distress syndrome and 28-day mortality in sepsis patients

We aimed to investigate the predictive value of microRNA 103 (MIR103) and microRNA 107 (MIR107) for acute respiratory distress syndrome (ARDS) risk, as well as their correlations with overall disease severity and prognosis in sepsis patients.Plasma samples were collected from 196 sepsis patients within 24 hours after enrollment and from 196 healthy individuals (as healthy controls (HCs)) at enrollment. Plasma MIR103 and MIR107 were detected by reverse transcription-quantitative polymerase chain reaction.MIR103 and MIR107 were both decreased in ARDS sepsis patients and non-ARDS sepsis patients compared to HCs, and were reduced in ARDS sepsis patients than non-ARDS sepsis patients. Decreased MIR103 (area under curve (AUC): 0.727, 95% confidence interval (CI): 0.619-0.835) and MIR107 (AUC: 0.694, 95% CI: 0.577-0.811) predicted increased ARDS risk in sepsis patients. Meanwhile, MIR103 and MIR107 were negatively correlated with acute pathologic and chronic health evaluation (APACHE) II score, sequential organ failure assessment (SOFA) score, serum creatinine, C-reactive protein, tumor necrosis factor, interleukin 1β, interleukin 6 and interleukin 8, while positively correlated with albumin in sepsis patients. For prognosis, 28-day mortality was increased in ARDS sepsis patients compared to non-ARDS sepsis patients. Finally, MIR103 and MIR107 were reduced in deaths than survivors of sepsis patients, and decreased MIR103 (AUC: 0.704, 95% CI: 0.626-0.782) as well as MIR107 (AUC: 0.649, 95% CI: 0.569-0.729) predicted increased 28-day mortality risk in sepsis patients.MiR-103 and MIR107 were predictive biomarkers for risks of ARDS and 28-day mortality in sepsis patients, which might improve the management of sepsis.

miR-15/107 microRNA Gene Group: Characteristics and Functional Implications in Cancer

The miR-15/107 group of microRNAs (miRNAs) encloses 10 annotated human members and is defined based on the presence of the sequence AGCAGC near the mature miRNAs’ 5′ end. Members of the miR-15/107 group expressed in humans are highly evolutionarily conserved, and seven of these miRNAs are widespread in vertebrate species. Contrary to the majority of miRNAs, which recognize complementary sequences on the 3′UTR region, some members of the miR-15/107 group are peculiarly characterized by the ability to target the coding sequence (CDS) of their target mRNAs, inhibiting translation without strongly affecting their mRNA levels. There is compelling evidence that different members of the miR-15/107 group regulate overlapping lists of mRNA targets but also show target specificity. The ubiquitously expressed miR-15/107 gene group controls several human cellular pathways, such as proliferation, angiogenesis, and lipid metabolism, and might be altered in various diseases, such as neurodegenerative diseases and cancer. Intriguingly, despite sharing the same seed sequence, different members of this family of miRNAs may behave as oncomiRs or as tumor suppressor miRNAs in the context of cancer cells. This review discusses the regulation and functional contribution of the miR-15/107 group to the control of gene expression. Moreover, we particularly focus on the contribution of specific miR-15/107 group members as tumor suppressors in breast cancer, reviewing literature reporting their ability to function as major controllers of a variety of cell pathways and to act as powerful biomarkers in this disease.

Role of ncRNAs in modulation of liver fibrosis by extracellular vesicles

Extracellular vesicles (EVs) are small membrane vesicles carrying bioactive lipids, proteins and nucleic acids of the cell of origin. In particular, EVs carry non-coding RNAs (ncRNAs) and the vesicle membrane may protect them from degradation. Once released within the extracellular space, EVs can transfer their cargo, including ncRNAs, to neighboring or distant cells, thus inducing phenotypical and functional changes that may be relevant in several physio-pathological conditions. This review provides an overview of the role of EV-carried ncRNAs in the modulation of liver fibrosis. In particular, we focused on EV-associated microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) involved into the development of liver fibrosis and on the potential use of EV-associated ncRNAs as diagnostic and prognostic biomarkers of liver fibrosis.

Expression profiling and analysis of some miRNAs in subcutaneous white adipose tissue during development of obesity

Background

MicroRNAs are emerging as new mediators in the regulation of adipocyte physiology and have been approved to play a role in obesity. Despite several studies have focused on microRNA expression profiles and functions in different metabolic tissues, little is known about their response to nutritional interventions in white adipose tissue during obesity stages, and whether they differ in this response to weight-reduction strategy is poorly understood. Our objectives were to study the dysregulation of some miRNAs in subcutaneous inguinal white adipose tissue during weight change, expansion/reduction; in response to both a high-fat diet and switching to a normal diet feeding, and to evaluate them as potential biomarkers and therapeutic targets for early obesity management

Method

A hundred 6-week-old male Wister rats were randomly divided into a normal diet group (N.D), a high-fat diet group (H.F.D), and a switched to a normal diet group (H.F.D/N.D). At the beginning and at intervals 2 weeks, serum lipid, hormone levels, total body fat mass, and inguinal subcutaneous white adipose tissue mass (WAT) measurements were recorded using dual-energy X-ray absorptiometry (DEXA). The expression levels of microRNAs were evaluated using real-time PCR.

Results

Significant alterations were observed in serum glucose, lipid profile, and adipokine hormones during the early stages of obesity development. Alteration in rno-mir 30a-5p, rno-mir 133a-5p, and rno-mir 107-5p expression levels were observed at more than one time point. While rno-let-7a-5p, rno-mir 193a-5p, and rno-mir125a-5p were downregulated and rno-mir130a-5p was upregulated at all time points within 2 to 4 weeks in response to H.F.D feeding for 10 weeks. The impact of switching to normal diet has a reversed effect on lipid profile, adipokine hormone levels, and some miRNAs. The bioinformatics results have identified a novel and important pathway related to inflammatory signalling.

Conclusion

Our research demonstrated significant alterations in some adipocyte-expressed miRNAs after a short time of high caloric diet consumption. This provides further evidence of the significant role of nutrition as an epigenetic factor in regulation of lipid and glucose metabolism genes by modulating of related key miRNAs. Therefore, we suggest that miRNAs could be used as biomarkers for adiposity during diet-induced obesity. Perhaps limitation in calories intake is a way to manipulate obesity and associated metabolic disorders. Further studies are needed to fully elucidate the role of microRNAs in the development of obesity

Oral Administration of Bovine and Porcine Milk Exosome Alter miRNAs Profiles in Piglet Serum

Breast milk is the most important nutrient source for newborn mammals. Studies have reported that milk contains microRNAs (miRNAs), which are potential regulatory components. Currently, existing functional and nutritional two competing hypotheses in milk field though little date have been provided for nutritional hypothesis. In this study, we used the qRT-PCR method to evaluated whether milk miRNAs can be absorbed by newborn piglets by feeding them porcine or bovine milk. The result showed that miRNA levels (miR-2284×, 2291, 7134, 1343, 500, 223) were significantly different between bovine and porcine milk. Four miRNAs (miR-2284×, 2291, 7134, 1343) were significantly different in piglet serum after feeding porcine or bovine milk. After separated milk exosomes by ultracentrifugation, the results showed the selected milk miRNAs (miR-2284×, 2291, 7134, 1343) were present in both exosomes and supernatants, and the miRNAs showed the coincidental expression in IPEC-J2 cells. All our founding suggested that the milk miRNAs can be absorbed both in vivo and in vitro, which will building the foundation for understanding whether these sort of miRNAs exert physiological functions after being absorbed and provided additional evidence for the nutritional hypotheses.

Circulating miR-103 family as potential biomarkers for type 2 diabetes through targeting CAV-1 and SFRP4

AIMS

MicroRNA-103 (miR-103) family plays important roles in regulating glucose homeostasis in type 2 diabetes mellitus (DM2). However, the underlying mechanisms remain poorly characterized. The objective of this study was to test the hypothesis that circulating miR-103a and miR-103b, which regulate CAV-1 and SFRP4, respectively, are novel biomarkers for diagnosis of DM2.

METHODS

We determined the predictive potential of circulating miR-103a and miR-103b in pre-DM subjects (pre-DM), noncomplicated diabetic subjects, and normal glucose-tolerance individuals (control) using bioinformatic analysis, qRT-PCR, luciferase assays, and ELISA assays.

RESULTS

We found that both miR-103a and miR-103b had high complementarity and conservation, modulated reporter gene expression through seed sequences in the 3'UTRs of CAV-1 and SFRP4 mRNA, and negatively regulated their mRNA and protein levels, respectively. We also found that increased miR-103a and decreased miR-103a in plasma were significantly and negatively correlated with reduced CAV-1 levels and elevated SFRP4 levels in pre-DM and DM2, respectively, and were significantly associated with glucose metabolism, HbA1c levels, and other DM2 risk factors for progression from a normal individual to one with pre-DM. Furthermore, we demonstrated that the reciprocal changes in circulating miR-103a and miR-103b not only provided high sensitivity and specificity to differentiate the pre-DM population but also acted as biomarkers for predicting DM2 with high diagnostic value.

CONCLUSIONS

These findings suggest that circulating miR-103a and miR-103b may serve as novel biomarkers for diagnosis of DM2, providing novel insight into the mechanisms underlying pre-DM.

P53/PANK1/miR-107 signalling pathway spans the gap between metabolic reprogramming and insulin resistance induced by high-fat diet

High-fat diet (HFD) leads to obesity, type II diabetes mellitus (T2DM) and increases the coincidence of cardiovascular diseases and cancer. Insulin resistance (IR) is considered as the 'common soil' of those diseases. Furthermore, people on HFD showed restrained glycolysis and enhanced fatty acid oxidation, which is the so-called metabolic reprogramming. However, the relationship between metabolic reprogramming and IR induced by HFD is still unclear. Here, we demonstrate that PANK1 and miR-107 were up-regulated in the liver tissue of mice on HFD for 16 weeks and involved in metabolic reprogramming induced by palmitate acid (PA) incubation. Importantly, miR-107 within an intron of PANK1 gene facilitated IR by targeting caveolin-1 in AML12 cells upon PA incubation. Moreover, we identify that HFD enhanced P53 expression, and activation of P53 with nutlin-3a induced PANK1 and miR-107 expression simultaneously in transcriptional level, leading to metabolic reprogramming and IR, respectively. Consistently, inhibition of P53 with pifithrin-α hydrobromide ameliorated PA-induced metabolic reprogramming and IR. Thus, our results revealing a new mechanism by which P53 regulate metabolism. In addition, the results distinguished the different roles of PANK1 and its intron miR-107 in metabolic regulation, which will provide more accurate intervention targets for the treatment of metabolic diseases.

ncRNAs: New Players in Mitochondrial Health and Disease?

The regulation of mitochondrial proteome is unique in that its components have origins in both mitochondria and nucleus. With the development of OMICS technologies, emerging evidence indicates an interaction between mitochondria and nucleus based not only on the proteins but also on the non-coding RNAs (ncRNAs). It is now accepted that large parts of the non‐coding genome are transcribed into various ncRNA species. Although their characterization has been a hot topic in recent years, the function of the majority remains unknown. Recently, ncRNA species microRNA (miRNA) and long-non coding RNAs (lncRNA) have been gaining attention as direct or indirect modulators of the mitochondrial proteome homeostasis. These ncRNA can impact mitochondria indirectly by affecting transcripts encoding for mitochondrial proteins in the cytoplasm. Furthermore, reports of mitochondria-localized miRNAs, termed mitomiRs, and lncRNAs directly regulating mitochondrial gene expression suggest the import of RNA to mitochondria, but also transcription from the mitochondrial genome. Interestingly, ncRNAs have been also shown to hide small open reading frames (sORFs) encoding for small functional peptides termed micropeptides, with several examples reported with a role in mitochondria. In this review, we provide a literature overview on ncRNAs and micropeptides found to be associated with mitochondrial biology in the context of both health and disease. Although reported, small study overlap and rare replications by other groups make the presence, transport, and role of ncRNA in mitochondria an attractive, but still challenging subject. Finally, we touch the topic of their potential as prognosis markers and therapeutic targets.

Coenzyme A and Its Thioester Pools in Obese Zucker and Zucker Diabetic Fatty Rats

Feeding behavior is closely related to hypothalamic malonyl-CoA level in the brain and diet-induced obesity affects total CoA pools in liver. Herein, we performed a comprehensive analysis of the CoA pools formed in thirteen tissues of Zucker and Zucker diabetic fatty (ZDF) rats. Hypothalamic malonyl-CoA levels in obese rats remained low and were almost the same as those of lean rats, despite obese rats having much higher content of leptin, insulin, and glucose in their sera. Regardless of the fa-genotypes, larger total CoA pools were formed in the livers of ZDF rats and the size of hepatic total CoA pools in Zucker rats showed almost one tenth of the size of ZDF rats. The decreased total CoA pool sizes in Zucker rats was observed in the brown adipose tissues, while ZDF-fatty rats possessed 6% of total CoA pool in the lean rats in response to fa deficiency. This substantially lower CoA content in the obese rats would be disadvantageous to non-shivering thermogenesis. Thus, comparing the intracellular CoA behaviors between Zucker and ZDF rats, as well as the lean and fatty rats of each strain would help to elucidate features of obesity and type 2 diabetes in combination with result (s) of differential gene expression analysis and/or comparative genomics.

MicroRNA-103 represses hepatic de novo lipogenesis and alleviates NAFLD via targeting FASN and SCD1

MicroRNAs are well acknowledged as key mediators in the development of chronic metabolic diseases, including NAFLD. However, their roles in hepatic lipid metabolism and fatty liver still remain well elucidated. Here, we found that miR-103 represses de novo lipogenesis (DNL) and dampens the development of obesity/diet-induced fatty liver through targeting at Fasn and Scd1 in mouse liver. miR-103, robustly amplified in obese livers, inhibits the expression of Fasn and Scd1 via directly interacting with their mRNA 3' untranslated regions. Upregulated miR-103 sufficiently reduces the expression of Fasn and Scd1 and blocks the lipid accumulation in oleate-incubated hepatocytes. Furthermore, specifically overexpressing miR-103 in mouse liver by adenovirus significantly inhibits hepatic DNL to repress HCD-promoted hepatic lipid contents as well as NAFLD development. Meanwhile, enforced expression of hepatic miR-103 also alleviates obesity-associated fatty liver via reducing Fasn and Scd1 in db/db mice. Together, our study reveals a critical role of miR-103 in lipid homeostasis of liver and pathogenesis of NAFLD.

The Current State of MicroRNAs as Restenosis Biomarkers

In-stent restenosis corresponds to the diameter reduction of coronary vessels following percutaneous coronary intervention (PCI), an invasive procedure in which a stent is deployed into the coronary arteries, producing profuse neointimal hyperplasia. The reasons for this process to occur still lack a clear answer, which is partly why it remains as a clinically significant problem. As a consequence, there is a vigorous need to identify useful non-invasive biomarkers to differentiate and follow-up subjects at risk of developing restenosis, and due to their extraordinary stability in several bodily fluids, microRNA research has received extensive attention to accomplish this task. This review depicts the current understanding, diagnostic potential and clinical challenges of microRNA molecules as possible blood-based restenosis biomarkers.

Resveratrol Reduces Lipid Accumulation through Upregulating the Expression of MicroRNAs Regulating Fatty Acid Bet Oxidation in Liver Cells: Evidence from In-vivo and In-vitro Studies

MicroRNAs have been shown to regulate lipogenesis in liver. The aim of the present study was to investigate whether the effects of resveratrol (RSV) on lipogenesis are associated with the changes in the expression of two miRNAs (miR-107 and miR-10b) that regulate lipogenic pathways. 30 wild type C57BL/6j male mice were randomly fed three diets: a standard chow diet (ND), a high fat diet (HFD, 60% fat) and the high fat diet supplemented with 0.4% RSV (HFD-RSV) for 16 weeks. HepG2 cells were treated with high glucose (33 mM) and RSV (20 µM) for 24 h. The expression of the genes and miRNAs were measured by real-time PCR. Triglyceride level was increased in the liver of mice and HepG2 cells. In both animal and In-vitro experiments, triglyceride level was significantly decreased in groups treated with RSV. The expression of the miR-107 and miR-10b was significantly upregulated in the liver of HFD mice, whereas HFD-RSV group demonstrated a significant lower expression of both miRNAs compared to HFD group. In addition, RSV treatment significantly upregulated the expression of CPT-1a and PPARα genes in the liver of HFD mice. Moreover, treatment with RSV could reduce the expression of miR-107 and miR-10b and increase the expression of CPT-1a and PPARα in HG-treated HepG2 cells. These evidence, as a whole, suggest that RSV could exert its anti-lipogenic effect partially through alterations in the expression of miR-107 and miR-10b in liver cells.

Mitochondrial MiRNA in Cardiovascular Function and Disease

MicroRNAs (miRNAs) are small noncoding RNAs functioning as crucial post-transcriptional regulators of gene expression involved in cardiovascular development and health. Recently, mitochondrial miRNAs (mitomiRs) have been shown to modulate the translational activity of the mitochondrial genome and regulating mitochondrial protein expression and function. Although mitochondria have been verified to be essential for the development and as a therapeutic target for cardiovascular diseases, we are just beginning to understand the roles of mitomiRs in the regulation of crucial biological processes, including energy metabolism, oxidative stress, inflammation, and apoptosis. In this review, we summarize recent findings regarding how mitomiRs impact on mitochondrial gene expression and mitochondrial function, which may help us better understand the contribution of mitomiRs to both the regulation of cardiovascular function under physiological conditions and the pathogenesis of cardiovascular diseases.

MiR-16a Regulates Milk Fat Metabolism by Targeting Large Tumor Suppressor Kinase 1 (LATS1) in Bovine Mammary Epithelial Cells

Milk contains a number of beneficial fatty acids including short and medium chain and unsaturated conjugated and nonconjugated fatty acids. In this study, microRNA sequencing of mammary tissue collected in early-, peak-, mid-, and late-lactation periods was performed to determine the miRNA expression profiles. miR-16a was one of the differentially expressed miRNA and was selected for in-depth functional studies pertaining to fatty acid metabolism. The mimic of miR-16a impaired fat metabolism [triacylglycerol (TAG) and cholesterol] while knock-down of miR-16a promoted fat metabolism in vitro in bovine mammary epithelial cells (BMECs). In addition, the in vitro work with BMECs also revealed that miR-16a had a negative effect on the cellular concentration of cis 9-C18:1, total C18:1, C20:1, and C22:1 and long-chain polyunsaturated fatty acids. Therefore, these data suggesting a negative effect on fatty acid metabolism extend the discovery of the key role of miR-16a in mediating adipocyte differentiation. Through a combination of bioinformatics analysis, target gene 3' UTR luciferase reporter assays, and western blotting, we identified large tumor suppressor kinase 1 (LATS1) as a target of miR-16a. Transfection of siRNA-LATS1 into BMECs led to increases in TAG, cholesterol, and cellular fatty acid concentrations, suggesting a positive role of LATS1 in mammary cell fatty acid metabolism. In summary, data suggest that miR-16a regulates biological processes associated with intracellular TAG, cholesterol, and unsaturated fatty acid synthesis through LATS1. These data provide a theoretical and experimental framework for further clarifying the regulation of lipid metabolism in mammary cells of dairy cows.

Roles of differential expression of miR-543-5p in GH regulation in rat anterior pituitary cells and GH3 cells

Growth hormone (GH) is an important hormone released by the pituitary gland that plays a key role in the growth and development of organisms. In our study, TargetScan analysis and the dual luciferase reporter assays were used to predict and screen for miRNAs that might act on the rat Gh1 gene, and we identified miR-543-5p. Then, the GH3 cell line and the primary rat pituitary cells were transfected with miRNA mimic, inhibitor, and siRNA. We detected the Gh1 gene expression and the GH secretion by real-time PCR and ELISAs, respectively, to verify the regulatory effect of miR-543-5p on GH secretion. The results showed that miR-543-5p can inhibit Gh1 mRNA expression and reduce GH secretion. MiR-543-5p inhibitor upregulated Gh1 mRNA expression and increased GH secretion compared with the negative control. In summary, miR-543-5p downregulates Gh1 expression, resulting in a decrease in GH synthesis and secretion, which demonstrates the important role of miRNAs in regulating GH and animal growth and development.