MicroRNAs and metabolic disorders - where are we heading?

Circulating microRNAs as Potential Biomarkers of Overweight and Obesity in Adults: A Narrative Review

In an obesogenic environment, such as the one we have been experiencing in recent decades, epigenetics provides answers to the relationship between hereditary and environmentally acquired patterns that have significantly contributed to the global rise in obesity prevalence. MicroRNA (miRNA) constitutes a diminutive non-coding small RNA molecule, 20 to 24 nucleotides in length, that functions as a regulator of gene regulation at the post-translational level. Circulating miRNAs (c-miRNAs) have been detected in multiple body fluids, including blood, plasma, serum, saliva, milk from breastfeeding mothers, and urine. These molecules hold significant therapeutic value and serve as extracellular biomarkers in metabolic diseases. They aid in the diagnosis and tracking of therapy responses, as well as dietary and physical habit modifications. Researchers have studied c-miRNAs as potential biomarkers for diagnosing and characterizing systemic diseases in people of all ages and backgrounds since then. These conditions encompass dyslipidemia, type 2 diabetes mellitus (T2DM), cardiovascular risk, metabolic syndrome, cardiovascular diseases, and obesity. This review therefore analyzes the usefulness of c-miRNAs as therapeutic markers over the past decades. It also provides an update on c-miRNAs associated with general obesity and overweight, as well as with the most prevalent pathologies in the adult population. It also examines the effect of different nutritional approaches and physical activity regarding the activity of miRNAs in circulation in adults with overweight or general obesity. All of this is done with the aim of evaluating their potential use as biomarkers in various research contexts related to overweight and obesity in adults.

Genetic and epigenetic alterations associated with gestational diabetes mellitus and adverse neonatal outcomes

Gestational diabetes mellitus (GDM) is a metabolic disorder, recognised during 24-28 weeks of pregnancy. GDM is linked with adverse newborn outcomes such as macrosomia, premature delivery, metabolic disorder, cardiovascular, and neurological disorders. Recent investigations have focused on the correlation of genetic factors such as β-cell function and insulin secretary genes (transcription factor 7 like 2, potassium voltage-gated channel subfamily q member 1, adiponectin etc.) on maternal metabolism during gestation leading to GDM. Epigenetic alterations like DNA methylation, histone modification, and miRNA expression can influence gene expression and play a dominant role in feto-maternal metabolic pathways. Interactions between genes and environment, resulting in differential gene expression patterns may lead to GDM. Researchers suggested that GDM women are more susceptible to insulin resistance, which alters intrauterine surroundings, resulting hyperglycemia and hyperinsulinemia. Epigenetic modifications in genes affecting neuroendocrine activities, and metabolism, increase the risk of obesity and type 2 diabetes in offspring. There is currently no treatment or effective preventive method for GDM, since the molecular processes of insulin resistance are not well understood. The present review was undertaken to understand the pathophysiology of GDM and its effects on adverse neonatal outcomes. In addition, the study of genetic and epigenetic alterations will provide lead to researchers in the search for predictive molecular biomarkers.

Regulatory Roles of MicroRNAs in the Pathogenesis of Metabolic Syndrome

Metabolic syndrome refers to a group of several disease conditions together with high glucose triglyceride levels, high blood pressure, lower high-density lipoprotein level, and large waist circumference. About 400 million people worldwide, one-third of the Euro-American population and 27% Chinese population over age 50 have it. microRNAs, an abundant novel class of endogenous small, non-coding RNAs in eukaryotic cells, act as negative controllers of gene expression by promoting either degradation/translational repression of target messenger RNA. More than 2000 microRNAs in the human genome have been identified and they are implicated in various biological & pathophysiological processes, including glucose homeostasis, inflammatory response, and angiogenesis. Destruction of microRNAs has a crucial role in the pathogenesis of obesity, cardiovascular disease, and diabetes. Recently the discovery of circulating microRNAs in human serum may help to promote metabolic crosstalk between organs and serves as a novel approach for the identification of various diseases, like Type 2 diabetes & atherosclerosis. In this review, we will discuss the most recent and up-to-date research on the pathophysiology and histopathology of metabolic syndrome besides their historical background and epidemiological highlight. As well as search the methodologies employed in this field of research and the potential role of microRNAs as novel biomarkers and therapeutic targets for metabolic syndrome in the human body. Furthermore, the significance of microRNAs in promising strategies, like stem cell therapy, which holds enormous promise for regenerative medicine in the treatment of metabolic disorders will also be discussed.

The effects of bupropion alone and combined with naltrexone on weight loss: a systematic review and meta-regression analysis of randomized controlled trials

BACKGROUND

The global prevalence of obesity and overweight is a significant concern in the field of public health. However, addressing and combating these conditions pose considerable challenges. Numerous interventional studies have been conducted to assess the possible impact of bupropion on weight reduction. The primary objective of this study was to conduct a comprehensive investigation into the effects of bupropiona alone and in combination with naltrexone on weight, body mass index (BMI), and waist circumferences (WC).

METHODS

A systematic search was conducted in five databases using established keywords. The purpose of this search was to uncover controlled trials that examined the impact of bupropion, either as a standalone intervention or in combination with naltrexone, on weight loss outcomes. The random-effects model analysis was used to provide pooled weighted mean difference and 95% confidence intervals.

RESULTS

Twenty five studies with 22,165 participants' were included in this article. The pooled findings showed that bupropion administration has an effect on lowering weight (WMD: -3.67 kg, 95% CI: -4.43 to -2.93) and WC (WMD: -2.98 cm, 95% CI -3.78 to -2.19) in compared with control groups. The analysis also showed that the effects of the present intervention on weight and WC during the intervention are > 26 weeks and ≤ 26 weeks compared to the other group, respectively. In addition, changes in weight loss and WC after receiving bupropion together with naltrexone were more compared to bupropion alone.

CONCLUSIONS

In conclusion, the addition of combination therapies like bupropion and naltrexone to lifestyle modifications including diet would cause significant weight loss.

Placental microRNA methylome signatures may serve as biomarkers and therapeutic targets for prenatally opioid-exposed infants with neonatal opioid withdrawal syndrome

Introduction: The neonate exposed to opioids in utero faces a constellation of withdrawal symptoms postpartum commonly called neonatal opioid withdrawal syndrome (NOWS). The incidence of NOWS has increased in recent years due to the opioid epidemic. MicroRNAs (miRNAs) are small non-coding RNA molecules that play a crucial role in gene regulation. Epigenetic variations in microRNAs (miRNAs) and their impact on addiction-related processes is a rapidly evolving area of research. Methods: The Illumina Infinium Methylation EPIC BeadChip was used to analyze DNA methylation levels of miRNA-encoding genes in 96 human placental tissues to identify miRNA gene methylation profiles as-sociated with NOWS: 32 from mothers whose prenatally opioid-exposed infants required pharmacologic management for NOWS, 32 from mothers whose prenatally opioid-exposed infants did not require treat-ment for NOWS, and 32 unexposed controls. Results: The study identified 46 significantly differentially methylated (FDR p-value ≤ 0.05) CpGs associated with 47 unique miRNAs, with a receiver operating characteristic (ROC) area under the curve (AUC) ≥0.75 including 28 hypomethylated and 18 hypermethylated CpGs as potentially associated with NOWS. These dysregulated microRNA methylation patterns may be a contributing factor to NOWS pathogenesis. Conclusion: This is the first study to analyze miRNA methylation profiles in NOWS infants and illustrates the unique role miRNAs might have in diagnosing and treating the disease. Furthermore, these data may provide a step toward feasible precision medicine for NOWS babies as well.

Anticancer Effects of Fucoxanthin through Cell Cycle Arrest, Apoptosis Induction, Angiogenesis Inhibition, and Autophagy Modulation

Cancer accounts for one in seven deaths worldwide and is the second leading cause of death in the United States, after heart disease. One of the standard cancer treatments is chemotherapy which sometimes can lead to chemoresistance and treatment failure. Therefore, there is a great need for novel therapeutic approaches to treat these patients. Novel natural products have exhibited anticancer effects that may be beneficial in treating many kinds of cancer, having fewer side effects, low toxicity, and affordability. Numerous marine natural compounds have been found to inhibit molecular events and signaling pathways associated with various stages of cancer development. Fucoxanthin is a well-known marine carotenoid of the xanthophyll family with bioactive compounds. It is profusely found in brown seaweeds, providing more than 10% of the total creation of natural carotenoids. Fucoxanthin is found in edible brown seaweed macroalgae such as Undaria pinnatifida, Laminaria japonica, and Eisenia bicyclis. Many of fucoxanthin's pharmacological properties include antioxidant, anti-tumor, anti-inflammatory, antiobesity, anticancer, and antihypertensive effects. Fucoxanthin inhibits many cancer cell lines' proliferation, angiogenesis, migration, invasion, and metastasis. In addition, it modulates miRNA and induces cell cycle growth arrest, apoptosis, and autophagy. Moreover, the literature shows fucoxanthin's ability to inhibit cytokines and growth factors such as TNF-α and VEGF, which stimulates the activation of downstream signaling pathways such as PI3K/Akt autophagy, and pathways of apoptosis. This review highlights the different critical mechanisms by which fucoxanthin inhibits diverse cancer types, such as breast, prostate, gastric, lung, and bladder development and progression. Moreover, this article reviews the existing literature and provides critical supportive evidence for fucoxanthin's possible therapeutic use in cancer.

Dietary Impacts on Gestational Diabetes: Connection between Gut Microbiome and Epigenetic Mechanisms

Gestational diabetes mellitus (GDM) is one of the most common obstetric complications due to an increased level of glucose intolerance during pregnancy. The prevalence of GDM increases due to the obesity epidemic. GDM is also associated with an increased risk of gestational hypertension and preeclampsia resulting in elevated maternal and perinatal morbidity and mortality. Diet is one of the most important environmental factors associated with etiology of GDM. Studies have shown that the consumption of certain bioactive diets and nutrients before and during pregnancy might have preventive effects against GDM leading to a healthy pregnancy outcome as well as beneficial metabolic outcomes later in the offspring's life. Gut microbiome as a biological ecosystem bridges the gap between human health and diseases through diets. Maternal diets affect maternal and fetal gut microbiome and metabolomics profiles, which consequently regulate the host epigenome, thus contributing to later-life metabolic health in both mother and offspring. This review discusses the current knowledge regarding how epigenetic mechanisms mediate the interaction between maternal bioactive diets, the gut microbiome and the metabolome leading to improved metabolic health in both mother and offspring.

Construction of a novel miRNA regulatory network and identification of target genes in gestational diabetes mellitus by integrated analysis

Backgrounds: Given the roles of microRNA (miRNA) in human diseases and the high incidence of gestational diabetes mellitus (GDM), the aim of the study was to examine miRNA signatures and crucial pathways, as well as possible biomarkers for GDM diagnosis. Methods: We conducted a two-stage study to explore functional miRNA and those target genes. Twelve participants (6 GDM and 6 non-GDM) were first enrolled and performed RNA sequencing analysis. The overlapped candidate genes were further screened in combination with differentially expressed genes (DEGs) of GEO datasets (GSE87295, GSE49524 and GSE19649) and potential target genes of DEMs. Candidate genes, critical pathways, small molecular compounds and regulatory networks were identified using bioinformatic analysis. The potential candidate genes were then investigated using the GEO dataset (GSE103552) of 19 participants in the validation stage (11 GDM and 8 non-GDM women). Results: Briefly, blood samples were sequenced interrogating 50 miRNAs, including 20 upregulated and 30 downregulated differentially expressed microRNAs(DEMs) in our internal screening dataset. After screening GEO databases, 123 upregulated and 70 downregulated genes were overlapped through DEGs of GEO datasets and miRNA-target genes. MiR-29b-1-5p-TGFB2, miR-142-3p-TGFB2, miR-9-5p-FBN2, miR-212-5p-FBN2, miR-542-3p-FBN1, miR-9-5p-FBN1, miR-508-3p-FBN1, miR-493-5p-THBS1, miR-29b-3p-COL4A1, miR-432-5p-COL5A2, miR-9-5p-TGFBI, miR-486-3p-SLC7A5 and miR-6515-5p-SLC1A5 were revealed as thirteen possible regulating pathways by integrative analysis. Conclusion: Overall, thirteen candidate miRNA-target gene regulatory pathways representing potentially novel biomarkers of GDM diseases were revealed. Ten chemicals were identified as putative therapeutic agents for GDM. This study examined a series of DEGs that are associated with epigenetic alternations of miRNA through an integrated approach and gained insight into biological pathways in GDM. Precise diagnosis and therapeutic targets of GDM would be further explored through putative genes in the future.

The potential role of miR-27a and miR-320a in metabolic syndrome in obese Egyptian females

BACKGROUND

Metabolic syndrome (MetS) is a combination of many health complications, such as obesity, high blood pressure, hyperlipidemia, hyperglycemia, and insulin resistance, with an increasing threat of type 2 diabetes mellitus (T2DM) and cardiovascular diseases. As the MetS develops, an alteration in the expression of some genes regulated by circulating microRNAs may also develop as a consequence. TaqMan microRNA primers specific for both miR-27a and miR-320a were used to estimate their expression levels in plasma samples collected from two groups: obese females with metabolic syndrome (n = 49) and lean healthy female volunteers (n = 23), to detect if their expression levels were deregulated with MetS.

RESULTS

The study results revealed that miR-27a was upregulated in the plasma of MetS group compared to the healthy controls, while miR-320a was downregulated (p ≤ 0.005). There was a highly significantly positive correlation between miR-27a expression and body mass index (BMI), waist circumference (WC), fasting blood glucose (FBG), insulin resistance (represented as HOMA-IR), and triglycerides (TG), while it showed significantly negative correlation only with HDL-cholesterol (p ≤ 0.0001). miR-320a showed significantly negative correlation with BMI, WC, waist-hip ratio (WHR), FBG, HOMA-IR, and TG. The expression value of miR-320a was positively correlated with HDL-cholesterol. Area under the curves (AUC) was equal to 1.000 for both microRNAs.

CONCLUSION

Our study added more evidence that monitoring changes in expression levels of both miR-27a and miR-320a in MetS patients could help in the evaluation of disease progression, risk, and susceptibility.

Micro-ribonucleic acid modulation with oxidative stress and inflammation in patients with type 2 diabetes mellitus - a review article

In parallel with the rapid growth of obesity, there is also an increase in the prevalence of type 2 diabetes mellitus (T2D) worldwide. Due to its complications, cardiovascular diseases are the leading cause of death in those patients. In the last two decades, special attention has been given to oxidative stress and inflammation, as the underlying mechanisms related to T2D occurrence and progression. Moreover, micro-ribonucleic acids (miRNAs) as new genetic biomarkers take an important place in the investigation of different metabolic pathways of insulin signaling. In this review article, we discuss microRNA modulation with oxidative stress and inflammation in patients with T2D. Better insight into the novel potential therapeutic targets for treatment of diabetes and its complications is of utmost importance for public health.

Metabolic Syndrome: Updates on Pathophysiology and Management in 2021

Metabolic syndrome (MetS) forms a cluster of metabolic dysregulations including insulin resistance, atherogenic dyslipidemia, central obesity, and hypertension. The pathogenesis of MetS encompasses multiple genetic and acquired entities that fall under the umbrella of insulin resistance and chronic low-grade inflammation. If left untreated, MetS is significantly associated with an increased risk of developing diabetes and cardiovascular diseases (CVDs). Given that CVDs constitute by far the leading cause of morbidity and mortality worldwide, it has become essential to investigate the role played by MetS in this context to reduce the heavy burden of the disease. As such, and while MetS relatively constitutes a novel clinical entity, the extent of research about the disease has been exponentially growing in the past few decades. However, many aspects of this clinical entity are still not completely understood, and many questions remain unanswered to date. In this review, we provide a historical background and highlight the epidemiology of MetS. We also discuss the current and latest knowledge about the histopathology and pathophysiology of the disease. Finally, we summarize the most recent updates about the management and the prevention of this clinical syndrome.

Fibroblast growth factor 21 levels and liver inflammatory biomarkers in obese subjects after weight loss

INTRODUCTION

Previous studies have hypothesized fibroblast growth factor 21 (FGF-21) as a potential biomarker of the inflammation associated with liver diseases, which is also receiving considerable attention for its potential application concerning the management of obesity and co-morbidities. This study aimed to analyze the response of FGF-21 after a weight loss intervention and the relationships with other putative inflammatory liver biomarkers.

MATERIAL AND METHODS

Sixty-six obese participants from the RESMENA study were evaluated at baseline and following a 6-month energy restriction treatment. Anthropometric, body composition by DXA, routine laboratory measurements, which included transaminases and γ-glutamyl transferase (GGT) were analyzed by standardized methods. Moreover, FGF-21, M30 fragment (M30) and plasminogen activator inhibitor-1 (PAI-I) were analyzed as recognized liver inflammatory related biomarkers with specific ELISA kits.

RESULTS

Most measurements related to hepatic damage, inflammation and adiposity status improved at the end of the 6-month nutritional intervention. In addition, ΔFGF-21 shifts showed statistical relationships with changes in ΔM30, ΔGGT and ΔPAI. The reduction of M30 showed significant associations with changes in transaminases. Furthermore, PAI-I changes were associated with ΔM30 and ΔGGT regardless of weight loss. A linear regression model was set up to assess the influence of ΔPAI-I and ΔM30 on the variability of ΔFGF-21 (23.8%) adjusted by weight loss.

CONCLUSIONS

These results demonstrated interactions of some liver inflammatory mediators, specifically M30 and PAI-I with FGF-21. Thus, more investigation about FGF-21 is required given that this protein could be a biomarker of the obesity-inflammation-liver process.

Effects of a short-term cold exposure on circulating microRNAs and metabolic parameters in healthy adult subjects

This discovery study investigated in healthy subjects whether a short‐term cold exposure may alter circulating microRNAs and metabolic parameters and if co‐expression networks between these factors could be identified. This open randomized crossover (cold vs no cold exposure) study with blind end‐ point evaluation was conducted at 1 center with 10 healthy adult male volunteers. Wearing a cooling vest perfused at 14°C for 2 h reduced the local skin temperature without triggering shivering, increased norepinephrine and blood pressure while decreasing copeptin, C‐peptide and heart rate. Circulating microRNAs measured before and after wearing the cooling vest twice (4 time points) identified 196 mature microRNAs with excellent reproducibility over 72 h. Significant correlations of microRNA expression with copeptin, norepinephrine and C‐peptide were found. A co‐expression‐based microRNA‐microRNA network, as well as microRNA pairs displaying differential correlation as a function of temperature were also detected. This study demonstrates that circulating miRNAs are differentially expressed and coregulated upon cold exposure in humans, supporting their use as predictive and dynamic biomarkers of cardio‐metabolic disorders.

Evaluation of circulating miRNAs and mRNAs expression patterns in autism spectrum disorder

Background

Autism spectrum disorder is a condition related to brain development that affects a person’s perception and socialization, resulting in problems in social interaction and communication. It has no single known cause, yet several different genes appear to be involved in autism. As a genetically complex disease, dysregulation of miRNA expression and miRNA–mRNA interactions might be a feature of autism spectrum disorder. The aim of the current study was to investigate the expression profile of circulating miRNA-128, miRNA-7 and SHANK gene family in ASD patients and to assess the possible influence of miRNA-128 and miRNA-7 on SHANK genes, which might provide an insight into the pathogenic mechanisms of ASD and introduce noninvasive molecular biomarkers for the disease diagnosis and prognosis. Quantitative real-time PCR technique was employed to determine expression levels of miRNA-128, miRNA-7 and SHANK gene family in blood samples of 40 autistic cases along with 30 age- and sex-matched normal volunteer subjects.

Results

Our study revealed a statistical significant upregulation of miRNA-128 expression levels in ASD cases compared to controls (p value < 0.001). A statistical significant difference in SHANK-3 expression was encountered on comparing cases to controls (p value < 0.001). However, miRNA-7 expression showed no significant difference between the studied groups.

Conclusions

MiRNA-128 and SHANK-3 gene are emerging players in the field of ASD. They are promising candidates as noninvasive biomarkers in autism. Future studies are needed to emphasize their pivotal role.

Crosstalk Between Polygonatum kingianum, the miRNA, and Gut Microbiota in the Regulation of Lipid Metabolism

Objectives: Polygonatum kingianum is a medicinal herb used in various traditional Chinese medicine formulations. The polysaccharide fraction of P. kingianum can reduce insulin resistance and restore the gut microbiota in a rat model of aberrant lipid metabolism by down regulating miR-122. The aim of this study was to further elucidate the effect of P. kingianum on lipid metabolism, and the roles of specific miRNAs and the gut microbiota. Key findings: P. kingianum administration significantly altered the abundance of 29 gut microbes and 27 differentially expressed miRNAs (DEMs). Several aberrantly expressed miRNAs closely related to lipid metabolism were identified, of which some were associated with specific gut microbiota. MiR-484 in particular was identified as the core factor involved in the therapeutic effects of P. kingianum. We hypothesize that the miR-484-Bacteroides/Roseburia axis acts as an important bridge hub that connects the entire miRNA-gut microbiota network. In addition, we observed that Parabacteroides and Bacillus correlated significantly with several miRNAs, including miR-484, miR-122-5p, miR-184 and miR-378b. Summary: P. kingianum alleviates lipid metabolism disorder by targeting the network of key miRNAs and the gut microbiota.

Human Prostate Tissue MicroRNAs and Their Predicted Target Pathways Linked to Prostate Cancer Risk Factors

MicroRNAs are important in prostate cancer development, progression and metastasis. The aim of this study was to test microRNA expression profile in prostate tissue obtained from prostate cancer patients for associations with various prostate cancer related factors and to pinpoint the predicted target pathways for these microRNAs. Prostate tissue samples were obtained at prostatectomy from patients participating in a trial evaluating impact of pre-operative atorvastatin on serum prostate specific antigen (PSA) and Ki-67 expression in prostate tissue. Prostate tissue microRNA expression profiles were analyzed using OpenArray^® MicroRNA Panel. Pathway enrichment analyses were conducted for predicted target genes of microRNAs that correlated significantly with studied factors. Eight microRNAs correlated significantly with studied factors of patients after Bonferroni multiple testing correction. MiR-485-3p correlated with serum HDL-cholesterol levels. In atorvastatin-treated subjects, miR-34c-5p correlated with a change in serum PSA and miR-138-3p with a change in total cholesterol. In the placebo arm, both miR-576-3p and miR-550-3p correlated with HDL-cholesterol and miR-627 with PSA. In pathway analysis, these eight microRNAs related significantly to several pathways relevant to prostate cancer. This study brings new evidence from the expression of prostate tissue microRNAs and related pathways that may link risk factors to prostate cancer and pinpoint new therapeutic possibilities.

Nanoparticle Delivered Anti-miR-141-3p for Stroke Therapy

Ischemic stroke and factors modifying ischemic stroke responses, such as social isolation, contribute to long-term disability worldwide. Several studies demonstrated that the aberrant levels of microRNAs contribute to ischemic stroke injury. In prior studies, we established that miR-141-3p increases after ischemic stroke and post-stroke isolation. Herein, we explored two different anti-miR oligonucleotides; peptide nucleic acid (PNAs) and phosphorothioates (PS) for ischemic stroke therapy. We used US FDA approved biocompatible poly (lactic-co-glycolic acid) (PLGA)-based nanoparticle formulations for delivery. The PNA and PS anti-miRs were encapsulated in PLGA nanoparticles by double emulsion solvent evaporation technique. All the formulated nanoparticles showed uniform morphology, size, distribution, and surface charge density. Nanoparticles also exhibited a controlled nucleic acid release profile for 48 h. Further, we performed in vivo studies in the mouse model of ischemic stroke. Ischemic stroke was induced by transient (60 min) occlusion of middle cerebral artery occlusion followed by a reperfusion for 48 or 72 h. We assessed the blood-brain barrier permeability of PLGA NPs containing fluorophore (TAMRA) anti-miR probe after systemic delivery. Confocal imaging shows uptake of fluorophore tagged anti-miR in the brain parenchyma. Next, we evaluated the therapeutic efficacy after systemic delivery of nanoparticles containing PNA and PS anti-miR-141-3p in mice after stroke. Post-treatment differentially reduced both miR-141-3p levels in brain tissue and infarct injury. We noted PNA-based anti-miR showed superior efficacy compared to PS-based anti-miR. Herein, we successfully established that nanoparticles encapsulating PNA or PS-based anti-miRs-141-3p probes could be used as a potential treatment for ischemic stroke.

Usefulness of microRNA detection in the diagnostics of endometrial cancer

INTRODUCTION

MicroRNAs (miRNAs) are noncoding RNAs that regulate gene expression and contribute to the development of cancer. They have been shown to be stable in tissue samples and may be promising diagnostic biomarkers for endometrial cancer.

MATERIAL AND METHODS

A retrospective cohort study of women diagnosed with endometrial cancer between January 2017 and December 2017 was performed at the Royal Cornwall Hospital. Archived formalin-fixed paraffin-embedded samples were obtained from patients with endometrial cancer and healthy women. MicroRNA was isolated and quantitative real-time polymerase chain reaction was used to detect expression levels of miRNAs.

RESULTS

A total of 76 women were included: 36 endometrial cancer patients, 40 healthy controls. A distinct panel of miR-200a, miR-200b, miR-200c, miR-205, and miR-182 showed an area under the curve of 0.958, sensitivity 92%, specificity 89%, positive predictive value of 89% (95% CI 82%-94%) and negative predictive value of 91% (95% CI 85%-96%) in diagnosing endometrial cancer. High miR-182 expression levels were significantly related to high-grade endometrioid tumors compared with low-grade tumors.

CONCLUSIONS

We demonstrated high diagnostic accuracy of miRNA for detecting endometrial cancer. In addition, miRNA contributed to an improvement in distinguishing between high-grade and low-grade endometrioid tumors.

Safety and efficacy of naltrexone for weight loss in adult patients - a systematic review

INTRODUCTION

This is a report of a systematic review of the safety and efficacy of naltrexone or naltrexone/bupropion on weight loss.

MATERIAL AND METHODS

The databases Medline, PubMed, and Embase as well as the Cochrane Controlled Trials Register for randomized controlled trials were searched for studies published from January 1966 to January 2018. A meta-analysis, randomised controlled trials, controlled trials, uncontrolled trials, cohort studies and open-label studies were analysed.

RESULTS

Of 191 articles, 14 fulfilled the inclusion criteria: 1 meta-analysis, 10 randomized controlled trials, and 3 studies without randomization were found. In these studies, the efficacy and safety of naltrexone/bupropion in obesity were analysed. In the majority of these studies, patients with at least 5% or 10% weight loss, as a primary outcome, were investigated. Generally, naltrexone/bupropion treatment can be a promising therapy for obese patients, including when combined with mental health treatment.

CONCLUSIONS

Based on these studies, it can be said that naltrexone/bupropion treatment is effective in the weight loss of overweight subjects. The naltrexone/bupropion treatment was well tolerated by the patients, and side effects were rarely reported.

MicroRNA profile and iron-related gene expression in hepatitis C-related hepatocellular carcinoma: a preliminary study

INTRODUCTION

Hepatocellular carcinoma (HCC) is very difficult to diagnose, especially in its early stages. Non-invasive diagnostic and prognostic factors for this cancer are urgently needed. The purpose of our study was to investigate whether the microRNAs (miRNAs) regulating genes involved in iron homeostasis, whose disruption is a hallmark of HCC, offer potential as diagnostic or prognostic factors of HCV-related hepatocellular carcinoma.

MATERIAL AND METHODS

Serum and tumor samples, and adjacent liver specimens, were obtained from 65 HCC patients. Additionally, serum samples were obtained from 65 healthy controls. In total, 28 circulating and eight tissue microRNA expression profiles were estimated by TaqMan qPCR.

RESULTS

The expression profiles of all tested miRNAs were altered in the hepatocellular carcinoma patients. Iron level was negatively related to serum miR-96 level in healthy controls. Although the expression of iron metabolism proteins correlated with the level of serum miRNA in the controls, this was not observed in cancer patients. In the group of cancer patients, Let-7a, miR-29b, and miR-133a were positively related to ferroportin, transferrin and ferritin levels, while miR-31, miR-221 and miR-532 were negatively related to ferroportin, transferrin receptor 1 and ferritin levels. According to ROC curve analyses, 15 miRNAs are able to discriminate with 100% sensitivity and specificity between hepatocellular carcinoma patients and healthy subjects, which is more efficient than α-fetoprotein.

CONCLUSIONS

Circulating miRNAs that regulate the expression of iron metabolism proteins should be evaluated as promising candidates for HCV-related HCC diagnostic agents.

Serum microRNA profiles in patients with autosomal dominant polycystic kidney disease show systematic dysregulation partially reversible by hemodialysis

INTRODUCTION

The impact of autosomal dominant polycystic kidney disease (ADPKD) on serum microRNAs (miRNA) is unknown.

MATERIAL AND METHODS

For profiling experiment we recruited 30 patients from three equinumerous groups: controls, ADPKD and ADPKD on hemodialysis. From the last group extra samples were collected for in pre-/postdialysis analysis. Additionally, 23 healthy volunteers were used for selected biomarker verification. Real-time PCR arrays were used for quantification of 752 miRNAs. Validation of selected miRNAs was performed in total RNA extracted from the serum and the exosomal fraction in pre-/postdialysis samples.

RESULTS

In total, 37 significant circulating miRNAs were found to differ between ADPKD patients and controls. In validation, 3 miRNAs with the highest fold change in comparison of dialyzed vs non-dialyzed patients (miR-532-3p, miR-320b, miR-144-5p) were not significantly altered by hemodialysis and from the top down-regulated ones, miR-27a-3p was significantly lower after dialysis in both total and exosomal fractions, miR-20a-5p was down-regulated in the exosomal fraction and miR-16-5p was unaltered by hemodialysis. MiR-16-5p was selected as the best circulating biomarker of ADPKD. Circulating representatives of the miR-17 family sharing the same seed region (miR-20a-5p, miR-93-5p and miR-106a-5p) showed significantly lower expression among dialyzed vs. non-dialyzed patients and their exosomal fraction dropped after hemodialysis.

CONCLUSIONS

The serum miRNAs among ADPKD patients differ substantially depending on the stage of CKD. The exosomal fraction of miRNA was more affected by dialysis than the total one. There was a common pattern of down-regulation for circulating miR-17 family members sharing the same seed region.

Vildagliptin, a dipeptidyl peptidase-4 inhibitor, attenuated endothelial dysfunction through miRNAs in diabetic rats

INTRODUCTION

Dipeptidyl peptidase-4 (DPP-4) inhibitors have various cellular effects that are associated with vascular protection. Here, we examined whether vildagliptin protected endothelial function in diabetic rats and explored the involved mechanism.

MATERIAL AND METHODS

Experimental diabetic rats were obtained by feeding a high-fat diet and administering an intraperitoneal injection of streptozotocin. Rats were randomly divided into four groups: controls (CON), diabetes (DM), diabetes + low dose of vildagliptin (Lvil, 10 mg/kg/day), and diabetes + high dose of vildagliptin (Hvil, 20 mg/kg/day). The metabolic parameters, endothelial function, and whole miRNA expression were measured.

RESULTS

After a 12-week treatment, vildagliptin-treated rats showed a significant reduction in blood glucose and blood lipid levels. Moreover, vildagliptin recovered aortic endothelial function in diabetic rats. We identified 31 miRNAs that were differentially expressed in the Hvil group compared with the diabetic group. Importantly, through miRNA target biological function and pathway analysis, we found that vildagliptin activated miR-190-5p to inhibit Ccl2 expression and inhibited miR-134-5p and miR-375-3p to increase Bdnf and Pdk1 expression in the aorta.

CONCLUSIONS

Our present study indicates that vildagliptin can recover endothelial function in diabetic rats. Anti-inflammatory and anti-apoptosis mechanisms and endothelial moderation may be the intervention targets of vildagliptin to protect the cardiovascular system through miRNA regulation.

Incretins and microRNAs: Interactions and physiological relevance

MicroRNAs (miRNA) are one class of the small regulatory RNAs that can impact the expression of numerous genes including incretin hormones and their G protein-coupled receptors. Incretin peptides, including GLP-1, GLP-2, and GIP, are released from the gastrointestinal tract and have an crucial role in the glucose hemostasis and pancreatic beta-cell function. These hormones and their analogs with a longer half-life, glucagon like peptide-1 receptor agonists (GLP1RA), modify the expression of miRNAs. Dipeptidyl peptidase IV (DPP-4) is an enzyme that degrades the incretin hormones and is inactivated by DPP-4 inhibitors, which are a class of compounds used in the management of type 2 diabetes. DPP-4 inhibitors may also increase or reduce the expression of miRNAs. In this review, we describe the possible interactions between miRNAs and incretin hormones and the relevance of such interactions to physiological processes and diseases.

Circulatory miRNA biomarkers of metabolic syndrome

AIMS

Circulatory microRNAs (c-miRNAs) exert important roles in the molecular dysregulation of cardio-metabolic diseases. However, little is known whether dysregulated miRNA expression occurs when risk factors are elevated, as in the metabolic syndrome (MetS). This study quantified c-miRNA expression in individuals with MetS compared to healthy, further examining the relationship of gene pathways with the underlying pathogenesis.

METHODS

Expression of 26 miRNAs was quantified in plasma from 40 women (20 healthy and 20 MetS) and 39 men (20 healthy and 19 MetS) by qPCR. In silico analysis was performed to investigate biological effects of the dysregulated miRNAs. Dysregulated miRNA expression was further validated in an independent cohort of 20 women (10 healthy and 10 MetS).

RESULTS

Regression model adjusted for age and sex identified miR-15a-5p, miR-17-5p, miR-370-3p and miR-375 as important predictors of MetS presence. Analysis of predictive miRNAs in the validation cohort strengthened the relationship with miR-15a-5p and miR-17-5p expression. These miRNAs share genes involved in the regulation of metabolic pathways including insulin, wnt, fatty acid metabolism and AMPK.

CONCLUSIONS

miR-15a-5p and miR-17-5p were identified as predictive biomarkers of MetS, irrespective of sexes, further demonstrating the relationship of c-miRNAs to known pathways of metabolic disturbances present in cardio-metabolic diseases.

Early and late outcomes after transcatheter versus surgical aortic valve replacement in obese patients

INTRODUCTION

Data on the early and late outcome following transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR) in obese patients are limited. We investigated whether TAVI may be superior to SAVR in obese patients.

MATERIAL AND METHODS

Obese patients (body mass index ≥ 30 kg/m²) who underwent either SAVR or TAVI were identified from the nationwide OBSERVANT registry, and their in-hospital and long-term outcomes were analysed. Propensity score matching was employed to identify two cohorts with similar baseline characteristics.

RESULTS

The propensity score matching provided 142 pairs balanced in terms of baseline risk factors. In-hospital and 30-day mortality did not differ between SAVR and TAVI obese patients (4.6% vs. 3.3%, p = 0.56, and 5.2% vs. 3.2%, p = 0.41, respectively). Obese SAVR patients experienced a higher rate of renal failure (12.4% vs. 3.6%, p = 0.0105) and blood transfusion requirement (60.3% vs. 25.7%, p < 0.0001) in comparison with TAVI patients. A higher rate of permanent pacemaker implantation (14.4% vs. 3.6%, p = 0.0018), and major vascular injuries (7.4% vs. 0%, p = 0.0044) occurred in the TAVI group. Five-year survival was higher in the SAVR group compared to the TAVI patient cohort (p = 0.0046), with survival estimates at 1, 3 and 5 years of 88.0%, 80.3%, 71.8% for patients undergoing SAVR, and 85.2%, 69.0%, 52.8% for those subjected to TAVI procedures.

CONCLUSIONS

In obese patients, both SAVR and TAVI are valid treatment options, although in the long term SAVR exhibited higher survival rates.

MiRNA-610 acts as a tumour suppressor to depress the cisplatin resistance in hepatocellular carcinoma through targeted silencing of hepatoma-derived growth factor

INTRODUCTION

Hepatic malignancy is one of the most common malignant neoplasms around the globe, and hepatocellular carcinoma (HCC) is the most common type. In this study, the roles and mechanisms of MiRNA-610 in the chemo resistance of HCC will be discussed.

MATERIAL AND METHODS

The expression of MiRNA-610 and hepatoma-derived growth factor (HDGF) in HCC tissues and cell line was detected by quantitative real-time PCR. The proliferation and chemo resistance were analysed by MTT assay. Flow cytometry was used to examine the apoptosis rate. Luciferase reporter assay was used to verify the correlation between MiRNA-610 and HDGF. HDGF protein expression was detected by Western blot.

RESULTS

Our study confirmed the low-expression of MiRNA-610 in HCC tissues and cell line. Its low expression was related to high T stages and poor differentiation of HCC, and was a prognostic factor for HCC. MiRNA-610 upregulation inhibited cell proliferation and induced apoptosis of HepG2 cells. MiRNA-610 enhancement decreased the half maximal inhibitory concentration for cisplatin (DDP) and depressed the DDP resistance in HepG2 cells. The specific correlation between MiRNA-610 and HDGF was tested by luciferase reporter assay and western blot. The transfection with HDGF expression vector up-regulated the expression of HDGF protein silenced by MiRNA-610 enhancement. HDGF overexpression was found to reverse partly the regulatory roles of MiRNA-610 on malignancy and DDP resistance.

CONCLUSIONS

MiRNA-610 not only played a tumour suppressor role in HCC but also affected chemo resistance to DDP. This role is mainly mediated through targeted silencing of the HDGF gene, which may offer a new potential therapeutic target and improve the clinical therapeutic effect for HCC.

An insight of microRNAs performance in carcinogenesis and tumorigenesis; an overview of cancer therapy

Importance of dysregulation and expression of microRNAs (miRNAs) has been confiemed in many disorders comprising cancer. In this way, different approaches to induce reprogramming from one cell type to another in oerder to control the cell normal mechanisem, comprising microRNAs, combinatorial small molecules, exosome-mediated reprogramming, embryonic microenvironment and also lineage-specific transcription agents, are involved in cell situation. Meaningly, besides the above factors, microRNAs are so special and have an impressive role in cell reprogramming. One of the main applications of cancer cell reprogramming is it's ability in therapeutic approach. Many insights in reprogramming mechanism have been recommended, and determining improvment has been aknolwged to develop reprogramming efficiency and possibility, permiting it to appear as practical therapy against all cancers. Conspiciously, the recent studies on the fluctuations and performance of microRNAs,small endogenous non-coding RNAs, as notable factors in carcinogenesis and tumorigenesis, therapy resistance and metastasis and as new non-invasive cancer biomarkers has a remarkable attention. This is due to their unique dysregulated signatures throughout tumor progression. Recognising miRNAs signatures capable of anticipating therapy response and metastatic onset in cancers might enhance diagnosis and therapy. According to the growing reports on miRNAs as novel non-invasive biomarkers in various cancers as a main regulators of cancers drug resistance or metastasis, the quest on whether some miRNAs have the ability to regulate both simultaneously is inevitable, yet understudied. The combination of genetic diagnosis using next generation sequencing and targeted therapy may contribute to the effective precision medicine for cancer therapy. Here, we want to review the practical application of microRNAs performance in carcinogenesis and tumorigenesis in cancer therapy.

Unhealthy Levels of Phthalates and Bisphenol A in Mexican Pregnant Women with Gestational Diabetes and Its Association to Altered Expression of miRNAs Involved with Metabolic Disease

Several studies indicate that bisphenol A (BPA) and phthalates may have a role in the development of metabolic diseases using different molecular pathways, including epigenetic regulatory mechanisms. However, it is unclear whether exposure to these chemicals modifies serum levels of miRNAs associated with gestational diabetes mellitus (GDM) risk. In the present study, we evaluated the serum levels of miRNAs associated with GDM (miR-9-5p, miR-16-5p, miR-29a-3p and miR-330-3p) and urinary levels of phthalate metabolites (mono-n-butyl phthalate (MBP), mono-isobutyl phthalate (MiBP), mono-benzyl phthalate (MBzP) and mono(2-ethyl hexyl) phthalate (MEHP)) and bisphenol A in GDM patients and women without GDM during the second trimester of gestation. We observed higher levels of miR-9-5p, miR-29a-3p and miR-330-3p in sera of patients with GDM compared to non-diabetic subjects. Phthalates were detected in 97–100% of urine samples, while BPA only in 40%. Urinary MEHP and BPA concentrations were remarkably higher in both study groups compared to previously reported data. Unadjusted MEHP levels and adjusted BPA levels were higher in non-diabetics than in GDM patients (p = 0.03, p = 0.02). We found positive correlations between adjusted urinary MBzP levels and miR-16-5p expression levels (p < 0.05), adjusted MEHP concentrations and miR-29a-3p expression levels (p < 0.05). We also found negative correlations between unadjusted and adjusted MBP concentrations and miR-29a-3p expression levels (p < 0.0001, p < 0.05), unadjusted MiBP concentrations and miR-29a-3p expression levels (p < 0.01). Urinary MEHP levels reflect a striking exposure to di(2-ethylhexyl) phthalate (DEHP) in pregnant Mexican women. This study highlights the need for a regulatory strategy in the manufacture of several items containing endocrine disruptors in order to avoid involuntary ingestion of these compounds in the Mexican population.

Integrated analysis of lncRNA, miRNA and mRNA expression profiling in patients with systemic lupus erythematosus

INTRODUCTION

A great deal of research has reported dysregulated expression of genes in systemic lupus erythematosus (SLE). This study aimed to analyze the lncRNA, miRNA and mRNA expression profile in SLE.

MATERIAL AND METHODS

RNA sequencing (RNA-seq) was used to detect the dysregulated RNAs in SLE. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analysis were used to explore the function of these differentially expressed RNAs.

RESULTS

2,353 lncRNAs, 827 mRNAs and 24 miRNAs were shown to be differentially expressed. GO analyses demonstrated that differentially expressed RNAs were enriched in a variety of molecular functions and biological processes including ribonucleotide, protein serine/threonine kinase activity function, regulation of B cell differentiation and others. KEGG pathway analyses revealed that differentially expressed mRNAs and lncRNAs were both enriched in FcγR-mediated phagocytosis, glycosaminoglycan biosynthesis-chondroitin sulfate/dermatan sulfate and glyoxylate and dicarboxylate metabolism pathways. The up-regulated miRNAs target genes were mainly enriched in the nuclear factor-κB (NF-κB) signaling pathway. The down-regulated miRNAs target genes were significantly enriched in metabolism of xenobiotics by cytochrome P450, bile secretion and terpenoid backbone biosynthesis pathways.

CONCLUSIONS

The current study reveals a comprehensive expression profile of lncRNAs, miRNAs and mRNAs and implies potential regulatory functions of these RNAs which are involved in the pathogenesis of SLE.

MiR-199a-3p inhibition facilitates cardiomyocyte differentiation of embryonic stem cell through promotion of MEF2C

MicroRNAs (miRNAs) is a small molecule (19-25 nucleotide) noncoding RNA that inhibits the expression of target messenger RNA (mRNA) at the posttranscriptional level as an endogenous regulator. There is an increasing evidence that miR-199a-3p has a significant effect on the development of multiple tumors. However, the specific roles of miR-199a-3p in myocardial differentiation of embryonic stem cell still need to be investigated. Method of the hanging drop was used to build the model of cardiomyocyte differentiation of stem cell and beating rate of embryoid bodies (EBs) was calculated. The levels of intracellular MEF2C, a-MHC, GATA4, Nkx2.5, and cTnT mRNA were measured by real-time quantitative polymerase chain reaction, while the expressions of miR-199a-3p were detected simultaneously. Protein levels of MEF2C, a-MHC, GATA4, Nkx2.5, and cTnT were quantified by western blot analysis. Immunoreactivities of MEF2C and cTnT were analyzed by immunofluorescence. The interaction between miR-199a-3p and its predicted target (3'-untranslated region of MEF2C mRNA) was verified by luciferase assay. MiR-199a-3p levels increased during cardiogenesis. MiR-199a-3p inhibitor increased the beating rate of EBs and promoted expressions of cardiac-specific markers (GATA4, Nkx2.5, cTnT, and a-MHC). Notably, miR-199a-3p inhibition brought upregulation of MEF2C, which is the target of miR-199a-3p that we predicted and verified experimentally. In addition, MEF2C siRNA decreased miR-199a-3p inhibitor promoted EBs beating and attenuated miR-199a-3p inhibitor-induced cTnT and MEF2C expressions. The results above showed that MEF2C was involved in the process of promoting the differentiation of stem cells into cardiac myocytes by miR-199a-3p inhibitors.

Hyperglycemia inhibition of endothelial miR-140-3p mediates angiogenic dysfunction in diabetes mellitus

OBJECTIVE

MicroRNAs (miRNAs) have emerged as promising regulators of diabetes mellitus (DM)-induced angiogenic dysfunction in endothelial cells (ECs), but information vis-à-vis the functional roles of distinct miRNAs remain surprisingly scarce. The current study was designed to elucidate the expression and function of miR-140-3p in diabetic ECs.

METHODS

miR-140-3p expression was evaluated in DM mouse model and in human ECs using RT-qPCR, Northern blot and RNA fluorescent in situ hybridization. Effects of miR-140-3p manipulation on ECs function were evaluated using cell proliferation, migration and in vitro tube formation assay. Regulation of FOXK2 transcription by miR-140-3p was determined by luciferase reporter assay and site-directed mutagenesis.

RESULTS

miR-140-3p expression was significantly down-regulated in high glucose-challenged ECs. Under normal conditions, miR-140-3p knockdown impaired endothelial proliferation and migration, and endothelial tube formation. Mechanistically, miR-140-3p exhibited its proangiogenic effects through directly inhibiting the expression of the forkhead transcription factor FOXK2. From a therapeutic standpoint, shRNA-mediated stable inhibition of FOXK2 effectively corrected miR-140-3p deficiency-induced impairment of ECs proliferation and in vitro angiogenesis.

CONCLUSION

Endothelial miR-140-3p positive regulates ECs function by directly targeting FOXK2 signaling. Deregulation of miR-140-3p/FOXK2 cascade by hyperglycemia thus serves as an important contributor to angiogenic dysfunction in DM.

Long non-coding RNA HOTAIR regulates proliferation, migration and invasion of human cervical cancer cells by modulating expression of MAPK1

INTRODUCTION

Accumulating evidence suggests that long non-coding RNAs (lncRNAs) are dysregulated in cancer cells and may be responsible for the development and progression of this disease. Herein, the role and therapeutic potential of aberrantly expressed lncRNA HOTAIR were investigated in cervical cancer.

MATERIAL AND METHODS

The expression profile of the lncRNA HOTAIR was determined by quantitative RT-PCR. CCK-8 and colony formation assays were used for determination of cell viability. DAPI and annexin V/PI assays were used for detection of apoptosis. Wound healing and transwell assays were used to monitor cell migration and invasion.

RESULTS

The results showed that the expression of lncRNA HOTAIR was significantly (p < 0.01) upregulated (up to 4.1-fold) in cervical cancer cell lines. Silencing of lncRNA HOTAIR expression resulted in inhibition of the proliferation of the DoTc2 cervical cancer cells via induction of apoptotic cell death. HOTAIR silencing also resulted in decrease of the migration and the invasive properties of the cervical cancer cells. HOTAIR has been reported to interact with MAPK1 in cancer cells, and in this study MAPK1 was found to be overexpressed (up to 3.7-fold) in all the cervical cancer cells and silencing of HOTAIR inhibited the expression of MAPK1 in DoTc2 cervical cancer cells. Silencing of MAPK1 in DoTc2 cells also inhibited their proliferation and metastasis via induction of apoptosis. Co-transfection experiments showed that silencing of MAPK1 and lncRNA HOTAIR causes inhibition of DoTc2 cell growth synergistically.

CONCLUSIONS

These results indicate that lncRNA HOTAIR may prove to be an important therapeutic target for management of cervical cancer.

Hepatic glycogen storage diseases: pathogenesis, clinical symptoms and therapeutic management

Glycogen storage diseases (GSDs) are genetically determined metabolic diseases that cause disorders of glycogen metabolism in the body. Due to the enzymatic defect at some stage of glycogenolysis/glycogenesis, excess glycogen or its pathologic forms are stored in the body tissues. The first symptoms of the disease usually appear during the first months of life and are thus the domain of pediatricians. Due to the fairly wide access of the authors to unpublished materials and research, as well as direct contact with the GSD patients, the article addresses the problem of actual diagnostic procedures for patients with the suspected diseases. Knowledge and awareness of the problem among physicians seem insufficient, and research on the diagnosis and treatment of GSD is still ongoing, resulting in a heterogeneous GSD typology and a changing way of its diagnosis and treatment.

Molecular Biomarkers for Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is a growing public health problem worldwide. The condition is associated with perinatal complications and an increased risk for future metabolic disease in both mothers and their offspring. In recent years, molecular biomarkers received considerable interest as screening tools for GDM. The purpose of this review is to provide an overview of the current status of single-nucleotide polymorphisms (SNPs), DNA methylation, and microRNAs as biomarkers for GDM. PubMed, Scopus, and Web of Science were searched for articles published between January 1990 and August 2018. The search terms included “gestational diabetes mellitus”, “blood”, “single-nucleotide polymorphism (SNP)”, “DNA methylation”, and “microRNAs”, including corresponding synonyms and associated terms for each word. This review updates current knowledge of the candidacy of these molecular biomarkers for GDM with recommendations for future research avenues.

Exercise and weight loss interventions and miRNA expression in women with breast cancer

PURPOSE

Obesity and weight gain are associated with comorbidities including a higher risk of tumor recurrence and cancer-related deaths among breast cancer (BC) survivors; however, the underlying mechanisms linking obesity and cancer are poorly understood. Given the lack of clinically validated BC biomarkers, obesity and weight-loss studies utilize serum biomarkers as the intermediary outcomes of tumor recurrence. Studies have indicated microRNAs (miRNA)s are reliable biomarkers for cancer. We hypothesized that miRNA expression correlates with obesity and weight loss amongst BC survivors. This would yield insight into the biological pathways by which this association occurs, enabling more precise development of therapeutics.

PATIENTS AND METHODS

We correlated baseline body mass index (BMI) with serum miRNA expression in 121 BC survivors enrolled in the Hormones and Physical Exercise (HOPE) trial. We then analyzed expression of the 35 most abundant miRNAs from HOPE in a six-month randomized controlled weight-loss trial (Lifestyle, Exercise, and Nutrition; LEAN) in 100 BC survivors. Ingenuity pathway analysis (IPA) software was used to identify biological pathway targets of the BMI-associated and intervention-responsive miRNAs using predictive biomarkers.

RESULTS

Pearson correlations in HOPE identified eight miRNAs associated with BMI, including miR-191-5p (r = - 0.22, p = 0.016) and miR-122-5p (r = 0.25, p = 0.0048). In the LEAN validation study, levels of miR-191-5p significantly increased during the six-month intervention (p = 0.082). Ingenuity Pathway Analysis identified "Estrogen-mediated S-phase entry" (HOPE p = 0.003; LEAN p < 0.001) and "Molecular mechanisms of cancer" (HOPE p = 0.02; LEAN p < 0.001) as the top canonical pathways that significantly correlated with BMI-associated and intervention-responsive miRNAs and contain obesity and cancer-relevant genes including the E2F family of transcription factors and CCND1, which have been implicated in sporadic BC.

CONCLUSION

While the association between obesity and BC recurrence and mortality has been demonstrated in the literature, mechanisms underlying the link between weight gain and cancer are unclear. Using two independent clinical trials, we identified novel miRNAs associative to BMI and weight loss that contribute to the development of cancer. Predictive modeling of miRNA targets identified multiple canonical pathways associated with cancer, highlighting potential mechanisms explaining the link between BMI and increased cancer risk.

All-cause mortality of metabolically healthy or unhealthy obese: risk stratification using myocardial perfusion imaging

Introduction

There is still controversy about the favorable prognosis of "metabolically healthy" (MH) obese. This study evaluated mortality and the use of myocardial perfusion scintigraphy (MPS) for risk stratification of MH or metabolically unhealthy (MU) obese or nonobese patients.

Material and methods

Patients without dyslipidemia, hypertension, or diabetes were considered MH, and those with ≥ 1 of these risk factors were considered MU. The MPS was categorized as normal, abnormal or ischemic. Patients were followed for 4.0 ±1.0 years for all-cause death.

Results

Of 2450 patients, 613 were obese. The MH obese patients less often had ischemia than MU obese, but there was no significant difference in the prevalence of ischemia compared to all nonobese. The annualized death rate of MH obese was 1.3% and of nonobese 1.0% (p = 0.4). An abnormal MPS and the MU status were independently associated with death, with hazard ratios of 1.85 and 1.72, respectively. A normal MPS identified patients with low risk among all subgroups; annualized rates of death were 1.0%, 1.1% and 1.0% for all nonobese, MH obese and MU obese, respectively (p = 0.63).

Conclusions

The annualized death rate of MH obese patients was not significantly different from that of nonobese individuals. Myocardial perfusion scintigraphy was able to stratify prognosis in the overall patient population. These data may be helpful to identify high-risk individuals, thereby improving patient management.

Long non-coding RNA nuclear paraspeckle assembly transcript 1 inhibits the apoptosis of retina Müller cells after diabetic retinopathy through regulating miR-497/brain-derived neurotrophic factor axis

BACKGROUND

The role of long non-coding RNA in diabetic retinopathy, a serious complication of diabetes mellitus, has attracted increasing attention in recent years. The purpose of this study was to explore whether long non-coding RNA nuclear paraspeckle assembly transcript 1 was involved in the context of diabetic retinopathy and its underlying mechanisms.

RESULTS

Our results revealed that nuclear paraspeckle assembly transcript 1 was significantly downregulated in the retina of diabetes mellitus rats. Meanwhile, miR-497 was significantly increased in diabetes mellitus rats' retina and high glucose-treated Müller cells, but brain-derived neurotrophic factor was increased. We also found that high glucose-induced apoptosis of Müller cells was accompanied by the significant downregulation of nuclear paraspeckle assembly transcript 1 in vitro. Further study demonstrated that high glucose-promoted Müller cells apoptosis through downregulating nuclear paraspeckle assembly transcript 1 and downregulated nuclear paraspeckle assembly transcript 1 mediated this effect via negative regulating miR-497. Moreover, brain-derived neurotrophic factor was negatively regulated by miR-497 and associated with the apoptosis of Müller cells under high glucose.

CONCLUSION

Our results suggested that under diabetic conditions, downregulated nuclear paraspeckle assembly transcript 1 decreased the expression of brain-derived neurotrophic factor through elevating miR-497, thereby promoting Müller cells apoptosis and aggravating diabetic retinopathy.