Elevated and Correlated Expressions of miR-24, miR-30d, miR-146a, and SFRP-4 in Human Abdominal Adipose Tissue Play a Role in Adiposity and Insulin Resistance

Role of secreted frizzled-related protein 4 in prediabetes and type 2 diabetes: a cross sectional study

BACKGROUND

Type 2 diabetes (T2D) has become an epidemic. Delays in diagnosis and as a consequent late treatment has resulted in high prevalence of complications and mortality. Secreted frizzled-related protein 4 (SFRP4), has been recently identified as a potential early biomarker of T2D related to obesity, due to its association with low grade inflammation in adipose tissue and impaired glucose metabolism. We aimed to evaluate the role of SFRP4 in prediabetes and T2D in a Mexican population.

METHODS

This was a cross-sectional study that included 80 subjects with T2D, 50 subjects with prediabetes and 50 healthy individuals. Fasting SFRP4 and insulin concentrations were measured by ELISA. Human serum IL-10, IL-6, IL-1β and IL-8 levels were quantified by flow cytometry. Genotyping was performed by TaqMan® probes.

RESULTS

Prediabetes and T2D patients had significantly higher SFRP4 levels than controls (P < 0.05). In turn, prediabetes subjects had higher SFRP4 concentrations than control subjects (P < 0.05). Additionally, the prediabetes and T2D groups had higher concentrations of proinflammatory molecules such as IL-6, IL-1β and IL-8, and lower concentrations of IL-10, an anti-inflammatory cytokine, than controls (P < 0.001). The serum SFRP4 concentrations were positively correlated with parameters that are elevated in prediabetes and T2D states, such as, HbA1c and homeostasis model assessment insulin resistance (HOMA-IR), (r = 0.168 and 0.248, respectively, P < 0.05). Also, serum SFRP4 concentrations were positively correlated with concentrations of pro-inflammatory molecules (CRP, IL-6, IL-1β and IL-8) and negatively correlated with the anti-inflammatory molecule IL-10, even after adjusting for body mass index and age (P < 0.001). The genetic variant rs4720265 was correlated with low HDL concentrations in T2D (P < 0.05).

CONCLUSIONS

SFRP4 correlates positively with the stage of prediabetes, suggesting that it may be an early biomarker to predict the risk of developing diabetes in people with high serum concentrations of SFRP4, although further longitudinal studies are required.

A Liquid Biopsy-Based Approach to Isolate and Characterize Adipose Tissue-Derived Extracellular Vesicles from Blood

Obesity is a major risk factor for multiple chronic diseases. Anthropometric and imaging approaches are primarily used to assess adiposity, and there is a dearth of techniques to determine the changes in adipose tissue (AT) at the molecular level. Extracellular vesicles (EVs) have emerged as a novel and less invasive source of biomarkers for various pathologies. Furthermore, the possibility of enriching cell or tissue-specific EVs from the biofluids based on their unique surface markers has led to classifying these vesicles as "liquid biopsies", offering valuable molecular information on hard-to-access tissues. Here, we isolated small EVs from AT (sEVAT) of lean and diet-induced obese (DIO) mice, identified unique surface proteins on sEVAT by surface shaving followed by mass spectrometry, and developed a signature of five unique proteins. Using this signature, we pulled out sEVAT from the blood of mice and validated the specificity of isolated sEVAT by measuring the expression of adiponectin, 38 adipokines on an array, and several adipose tissue-related miRNAs. Furthermore, we provided evidence of sEV applicability in disease prediction by characterizing sEVAT from the blood of lean and DIO mice. Interestingly, sEVAT-DIO cargo showed a stronger pro-inflammatory effect on THP1 monocytes compared to sEVAT-Lean and a significant increase in obesity-associated miRNA expression. Equally important, sEVAT cargo revealed an obesity-associated aberrant amino acid metabolism that was subsequently validated in the corresponding AT. Lastly, we show a significant increase in inflammation-related molecules in sEVAT isolated from the blood of nondiabetic obese (>30 kg/m2) individuals. Overall, the present study offers a less-invasive approach to characterize AT.

Non-coding RNAs: The link between maternal malnutrition and offspring metabolism

Early life nutrition is associated with the development and metabolism in later life, which is known as the Developmental Origin of Health and Diseases (DOHaD). Epigenetics have been proposed as an important explanation for this link between early life malnutrition and long-term diseases. Non-coding RNAs (ncRNAs) may play a role in this epigenetic programming. The expression of ncRNAs (such as long non-coding RNA H19, microRNA-122, and circular RNA-SETD2) was significantly altered in specific tissues of offspring exposed to maternal malnutrition. Changes in these downstream targets of ncRNAs lead to abnormal development and metabolism. This review aims to summarize the existing knowledge on ncRNAs linking the maternal nutrition condition and offspring metabolic diseases, such as obesity, type 2 diabetes (T2D) and non-alcoholic fatty liver disease (NAFLD).

Versatile role of miR-24/24-1*/24-2* expression in cancer and other human diseases

MiRNAs (miRs) have been proven to be well-validated therapeutic targets. Emerging evidence has demonstrated that intricate, intrinsic and paradoxical functions of miRs are context-dependent because of their multiple upstream regulators, broad spectrum of downstream molecular targets and distinct expression in various tissues, organs and disease states. Targeted therapy has become an emerging field of research. One key for the development of successful miR-based/targeted therapy is to acquire integrated knowledge of its regulatory network and its association with disease phenotypes to identify critical nodes of the underlying pathogenesis. Herein, we systematically summarized the comprehensive role of miR-24-3p (miR-24), along with its passenger strands miR-24-1-5p* (miR-24-1) and miR-24-2-5p* (miR-24-2), emphasizing their microenvironment, intracellular targets, and associated gene networks and regulatory phenotypes in 18 different cancer types and 13 types of other disorders. MiR-24 targets and regulates numerous genes in various cancer types and enhances the expression of several oncogenes (e.g., cMyc, BCL2 and HIF1), which are challenging in terms of druggability. In contrast, several tumor suppressor proteins (p21 and p53) have been reported to be downregulated by miR-24. MiR-24 also regulates the cell cycle and is associated with numerous cancer hallmarks such as apoptosis, proliferation, metastasis, invasion, angiogenesis, autophagy, drug resistance and other diseases pathogenesis. Overall, miR-24 plays an emerging role in the diagnosis, prognosis and pathobiology of various diseases. MiR-24 is a potential target for targeted therapy in the era of precision medicine, which expands the landscape of targetable macromolecules, including undruggable proteins.

Unique circulating microRNA associations with dysglycemia in people living with HIV and alcohol use

People living with HIV (PLWH) have increased prevalence of comorbid conditions including insulin resistance and at-risk alcohol use. Circulating microRNAs (miRs) may serve as minimally invasive indicators of pathophysiological states. We aimed to identify whether alcohol modulates circulating miR associations with measures of glucose/insulin dynamics in PLWH. PLWH (n = 96; 69.8% males) enrolled in the Alcohol & Metabolic Comorbidities in PLWH: Evidence-Driven Interventions (ALIVE-Ex) study were stratified into negative phosphatidylethanol (PEth < 8 ng/mL, n = 42) and positive PEth (PEth ≥ 8 ng/mL, n = 54) groups. An oral glucose tolerance test (OGTT) was administered, and total RNA was isolated from fasting plasma to determine absolute miR expression. Circulating miRs were selected based on their role in skeletal muscle (miR-133a and miR-206), pancreatic β-cell (miR-375), liver (miR-20a), and adipose tissue (miR-let-7b, miR-146a, and miR-221) function. Correlation and multiple regression analyses between miR expression and adiponectin, 2 h glucose, insulin, and C-peptide values were performed adjusting for body mass index (BMI) category, age, sex, and viral load. miR-133a was negatively associated with adiponectin (P = 0.002) in the negative PEth group, and miR-20a was positively associated with 2 h glucose (P = 0.013) in the positive PEth group. Regression analyses combining miRs demonstrated that miR-133a (P < 0.001) and miR-221 (P = 0.010) together predicted adiponectin in the negative PEth group. miR-20a (P < 0.001) and miR-375 (P = 0.002) together predicted 2 h glucose in the positive PEth group. Our results indicate that associations between miRs and measures of glucose/insulin dynamics differed between PEth groups, suggesting that the pathophysiological mechanisms contributing to altered glucose homeostasis in PLWH are potentially modulated by alcohol use.

microRNAs in Human Adipose Tissue Physiology and Dysfunction

In recent years, there has been a large amount of evidence on the role of microRNA (miRNA) in regulating adipose tissue physiology. Indeed, miRNAs control critical steps in adipocyte differentiation, proliferation and browning, as well as lipolysis, lipogenesis and adipokine secretion. Overnutrition leads to a significant change in the adipocyte miRNOME, resulting in adipose tissue dysfunction. Moreover, via secreted mediators, dysfunctional adipocytes may impair the function of other organs and tissues. However, given their potential to control cell and whole-body energy expenditure, miRNAs also represent critical therapeutic targets for treating obesity and related metabolic complications. This review attempts to integrate present concepts on the role miRNAs play in adipose tissue physiology and obesity-related dysfunction and data from pre-clinical and clinical studies on the diagnostic or therapeutic potential of miRNA in obesity and its related complications.

Down-regulation of microRNA-30d-5p is associated with gestational diabetes mellitus by targeting RAB8A

Gestational Diabetes Mellitus (GDM) is a complicated clinical process, and metabolic disorders during pregnancy are closely related to the structure and function of the placenta. The aberrant expression of miRNAs in the placenta may play a role in the occurrence and development of GDM. Analysis of microRNA (miRNA) expression signature in placenta showed that the level of miR-30d-5p was significantly down-regulated in GDM patients. This study aims to explore the possible mechanism of GDM under the regulation of miR-30d-5p. In situ hybridization and qRT-PCR assay showed that miR-30d expression down-regulated in the placentas from GDM patients compared with normal control group. The trophoblast cells proliferation and glucose uptake capacity were increased, the ability of migration and invasion were also improved after inhibiting the function of endogenous mature miR-30d-5p. Bioinformatics analysis and luciferase reporter assays showed that miR-30d-5p binds to the 3'UTR of RAB8A mRNA, resulting in RAB8A suppression. Moreover, the down-regulation of RAB8A could attenuate the increase in trophoblast cell proliferation, migration, invasion and glucose uptake induced by miR-30d-5p functional inhibitor. These data imply that miR-30d-5p expression is down-regulated in placental tissue from GDM patients and affects trophoblast cell functions by targeting RAB8A, which may provide new insight into the pathogenesis of GDM.

The Peculiar Trialogue between Pediatric Obesity, Systemic Inflammatory Status, and Immunity

Pediatric obesity is not only an energetic imbalance, but also a chronic complex multisystem disorder that might impair both the life length and quality. Its pandemic status should increase worldwide awareness regarding the long-term life-threatening associated complications. Obesity related complications, such as cardiovascular, metabolic, or hepatic ones, affect both short and long-term wellbeing, and they do not spare pediatric subjects, defined as life-threatening consequences of the systemic inflammatory status triggered by the adipose tissue. The energetic imbalance of obesity clearly results in adipocytes hypertrophy and hyperplasia expressing different degrees of chronic inflammation. Adipose tissue might be considered an immune organ due to its rich content in a complex array of immune cells, among which the formerly mentioned macrophages, neutrophils, mast cells, but also eosinophils along with T and B cells, acting together to maintain the tissue homeostasis in normal weight individuals. Adipokines belong to the class of innate immunity humoral effectors, and they play a crucial role in amplifying the immune responses with a subsequent trigger effect on leukocyte activation. The usefulness of complete cellular blood count parameters, such as leukocytes, lymphocytes, neutrophils, erythrocytes, and platelets as predictors of obesity-triggered inflammation, was also proved in pediatric patients with overweight or obesity. The dogma that adipose tissue is a simple energy storage tissue is no longer accepted since it has been proved that it also has an incontestable multifunctional role acting like a true standalone organ resembling to endocrine or immune organs.

Insulin micro-secretion in Type 1 diabetes and related microRNA profiles

The aim of this cross-sectional study was to compare plasma C-peptide presence and levels in people without diabetes (CON) and with Type 1 diabetes and relate C-peptide status to clinical factors. In a subset we evaluated 50 microRNAs (miRs) previously implicated in beta-cell death and associations with clinical status and C-peptide levels. Diabetes age of onset was stratified as adult (≥ 18 y.o) or childhood (< 18 y.o.), and diabetes duration was stratified as ≤ 10 years, 10–20 years and > 20 years. Plasma C-peptide was measured by ultrasensitive ELISA. Plasma miRs were quantified using TaqMan probe-primer mix on an OpenArray platform. C-peptide was detectable in 55.3% of (n = 349) people with diabetes, including 64.1% of adults and 34.0% of youth with diabetes, p < 0.0001 and in all (n = 253) participants without diabetes (CON). C-peptide levels, when detectable, were lower in the individuals with diabetes than in the CON group [median lower quartile (LQ)–upper quartile (UQ)] 5.0 (2.6–28.7) versus 650.9 (401.2–732.4) pmol/L respectively, p < 0.0001 and lower in childhood versus adult-onset diabetes [median (LQ–UQ) 4.2 (2.6–12.2) pmol/L vs. 8.0 (2.3–80.5) pmol/L, p = 0.02, respectively]. In the childhood-onset group more people with longer diabetes duration (> 20 years) had detectable C-peptide (60%) than in those with shorter diabetes duration (39%, p for trend < 0.05). Nine miRs significantly correlated with detectable C-peptide levels in people with diabetes and 16 miRs correlated with C-peptide levels in CON. Our cross-sectional study results are supportive of (a) greater beta-cell function loss in younger onset Type 1 diabetes; (b) persistent insulin secretion in adult-onset diabetes and possibly regenerative secretion in childhood-onset long diabetes duration; and (c) relationships of C-peptide levels with circulating miRs. Confirmatory clinical studies and related basic science studies are merited.

High density lipoprotein-associated miRNA is increased following Roux-en-Y gastric bypass surgery for severe obesity

Roux-en-Y gastric bypass (RYGB) is one of the most commonly performed weight-loss procedures, but how severe obesity and RYGB affect circulating HDL-associated microRNAs (miRNAs) remains unclear. Here, we aim to investigate how HDL-associated miRNAs are regulated in severe obesity and how weight loss after RYGB surgery affects HDL-miRNAs. Plasma HDLs were isolated from patients with severe obesity (n = 53) before and 6 and 12 months after RYGB by immunoprecipitation using goat anti-human apoA-I microbeads. HDLs were also isolated from 18 healthy participants. miRNAs were extracted from isolated HDL and levels of miR-24, miR-126, miR-222, and miR-223 were determined by TaqMan miRNA assays. We found that HDL-associated miR-126, miR-222, and miR-223 levels, but not miR-24 levels, were significantly higher in patients with severe obesity when compared with healthy controls. There were significant increases in HDL-associated miR-24, miR-222, and miR-223 at 12 months after RYGB. Additionally, cholesterol efflux capacity and paraoxonase activity were increased and intercellular adhesion molecule-1 (ICAM-1) levels decreased. The increases in HDL-associated miR-24 and miR-223 were positively correlated with an increase in cholesterol efflux capacity (r = 0.326, P = 0.027 and r = 0.349, P = 0.017, respectively). An inverse correlation was observed between HDL-associated miR-223 and ICAM-1 at baseline. Together, these findings show that HDL-associated miRNAs are differentially regulated in healthy participants versus patients with severe obesity and are altered after RYGB. These findings provide insights into how miRNAs are regulated in obesity before and after weight reduction and may lead to the development of novel treatment strategies for obesity and related metabolic disorders.

Secreted Frizzled Related Proteins in Cardiovascular and Metabolic Diseases

Abnormal gene expression and secreted protein levels are accompanied by extensive pathological changes. Secreted frizzled related protein (SFRP) family members are antagonistic inhibitors of the Wnt signaling pathway, and they were recently found to be involved in the pathogenesis of a variety of metabolic diseases, which has led to extensive interest in SFRPs. Previous reports highlighted the importance of SFRPs in lipid metabolism, obesity, type 2 diabetes mellitus and cardiovascular diseases. In this review, we provide a detailed introduction of SFRPs, including their structural characteristics, receptors, inhibitors, signaling pathways and metabolic disease impacts. In addition to summarizing the pathologies and potential molecular mechanisms associated with SFRPs, this review further suggests the potential future use of SFRPs as disease biomarkers therapeutic targets.

Dysregulation of Circulating miR-24-3p in Children with Obesity and Its Predictive Value for Metabolic Syndrome

INTRODUCTION

Obesity is a major risk factor for metabolic disorders in children. Therefore, it is particularly important to study the abnormal regulation of circulating miR-24-3p in obese children and its predictive value for metabolic syndrome.

METHODS

Serum samples were obtained from children with obesity (n = 45), obese children with metabolic syndrome (n = 52), and healthy controls (n = 50). The expression levels of miR-24-3p were detected by reverse transcription quantitative PCR. The ROC curve was used to evaluate the diagnostic value of miR-24-3p. Pearson's correlation analysis was performed to evaluate the relationship between serum miR-24-3p and different clinical parameters. Logistic regression analysis was used to evaluate the relationship between miR-24-3p and obesity with metabolic syndrome in children.

RESULTS

The expression of miR-24-3p was the highest in obese children with metabolic syndrome. ROC results showed that miR-24-3p had the ability to distinguish healthy individuals from obese children (area under the curve [AUC] = 0.951) and can predict the occurrence of metabolic syndrome for obese children (AUC = 0.890). The expression level of miR-24-3p was positively correlated with body mass index (r = 0.817, p < 0.001), fasting blood glucose (r = 0.798, p < 0.001), triglycerides (r = 0.773, p < 0.001), systolic blood pressure (r = 0.746, p < 0.001), and diastolic blood pressure (r = 0.623, p < 0.001), respectively. Logistic regression analysis showed that miR-24-3p was an independent influence factor for the occurrence of metabolic syndrome in obese children.

DISCUSSION/CONCLUSION

MiR-24-3p is a potential noninvasive marker for children with obesity and has predictive value for the occurrence of metabolic syndrome.

Metformin decreases miR-122, miR-223 and miR-29a in women with polycystic ovary syndrome

Metformin is associated with increased insulin sensitivity, whereas oral contraceptive pills (OCP) could increase the risk for type 2 diabetes (T2D) in women with polycystic ovary syndrome (PCOS). Certain miRNAs might serve as biomarkers for the risk of T2D. The aim of this study was to investigate changes in circulating miRNA levels during treatment with metformin and OCP in women with PCOS. Sixty-five women with PCOS according to Rotterdam criteria were randomized to metformin (2 g/day), metformin + OCP (150 mg desogestrel + 30 µg ethinylestradiol) or OCP alone for 12 months. Serum miRNA analysis was performed with individual RT-qPCR or Taqman low density array cards of 22 selected miRNAs previously related to PCOS, glucose and/or lipid metabolism. miR-122 and miR-29a levels were decreased after treatment with metformin compared with metformin + OCP and OCP group: miR-122: log2 difference -0.7 (P = 0.01) and -0.7 (P = 0.02), miR-29a: log2 difference -0.5 (P = 0.01) and -0.4 (P = 0.04), while miR-223 levels were decreased in the metformin + OCP group after treatment: log2 difference -0.5 (P = 0.02). During the treatment period, a significant weight loss was observed in the metformin group compared with the OCP group. In the OCP group, miRNA levels were unchanged during the treatment period. Levels of circulating miRNAs associated with lipid and glucose metabolism decreased during metformin treatment. Changes in miRNA levels in the metformin group could be explained by the simultaneous weight loss in the same group. These results support the notion that metformin treatment alone may be superior for metabolic health compared with OCP.

The Role of microRNAs in Metabolic Syndrome-Related Oxidative Stress

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

MicroRNAs and obesity-induced endothelial dysfunction: key paradigms in molecular therapy

The endothelium plays a pivotal role in maintaining vascular health. Obesity is a global epidemic that has seen dramatic increases in both adult and pediatric populations. Obesity perturbs the integrity of normal endothelium, leading to endothelial dysfunction which predisposes the patient to cardiovascular diseases. MicroRNAs (miRNAs) are short, single-stranded, non-coding RNA molecules that play important roles in a variety of cellular processes such as differentiation, proliferation, apoptosis, and stress response; their alteration contributes to the development of many pathologies including obesity. Mediators of obesity-induced endothelial dysfunction include altered endothelial nitric oxide synthase (eNOS), Sirtuin 1 (SIRT1), oxidative stress, autophagy machinery and endoplasmic reticulum (ER) stress. All of these factors have been shown to be either directly or indirectly caused by gene regulatory mechanisms of miRNAs. In this review, we aim to provide a comprehensive description of the therapeutic potential of miRNAs to treat obesity-induced endothelial dysfunction. This may lead to the identification of new targets for interventions that may prevent or delay the development of obesity-related cardiovascular disease.

Emerging functions of adipokines in linking the development of obesity and cardiovascular diseases

Increasing evidence shows that obesity is the critical factor in shaping cardio-metabolic phenotypes. However, the pathogenic mechanisms remain incompletely clarified. According to the published reports, adipose tissue communicates with several diverse organs, such as heart, lungs, and kidneys through the secretion of various cytokines named adipokines. The adipocytes isolated from obese mice or humans are dysfunctional with aberrant production of pro-inflammatory adipokines, which subsequently induce both acute and chronic inflammatory reaction and facilitate the process of cardio-metabolic disorder complications. Furthermore, the microenvironment within adipose tissue under obese status also influence the secretion of adipokines. Recently, given that several important adipokines have been completely researched and causally involved in various diseases, we could make a conclusion that adipokines play an essential role in modulating the development of cardio-metabolic disorder diseases, whereas several novel adipokines continue to be explored and elucidated. In the present review, we summarized the current knowledge of the microenvironment of adipose tissue and the published mechanisms whereby adipocytes affects obesity and cardiovascular diseases. On the other hand, we also provide the evidence to elucidate the functions of adipokines in controlling and regulating the inflammatory reactions which contribute to obesity and cardiovascular disease.

Circulating miRNA Signatures Associated with Insulin Resistance in Adolescents with Obesity

PURPOSE

MicroRNAs (miRNAs) are implicated in metabolic changes accompanying progression of obesity, insulin resistance (IR), and metabolic disorders in children. Identifying circulating miRNAs that uniquely associate with these disorders may be useful in early identification and prevention of obesity-related complications. We aimed to identify circulating miRNA signatures that distinguish adolescents with obesity and IR from those with obesity unaccompanied by IR.

METHODS

Adolescents (aged 10-17 years) with obesity were recruited from a weight management clinic. Fasting serum samples were obtained from 33 participants. A total of 179 miRNAs were queried by a quantitative RT-PCR-based miRNA focus panel. Differentially expressed miRNAs were compared between groups using Student's t-test or one-way ANOVA analysis, and the association between IR evaluated by homeostatic model assessment model (HOMA-IR > 4) and body mass index (BMI) status was assessed using Pearson's correlation analysis.

RESULTS

We found an expression pattern consisting of 12 elevated miRNAs linked to IR in obese adolescents. miR-30d, -221, and -122 were significantly correlated with clinical and biochemical markers of obesity and IR, suggestive of IR in adolescents at risk.

CONCLUSION

Specific signatures of circulating miRNAs reflected metabolic phenotypes and predicted the presence of IR in adolescents with obesity, suggesting that miRNA indicators may identify obesity-associated complications in childhood. Further studies will be needed to understand cause versus effect and the mechanisms by which IR status links to changes in blood miRNA profiles.

Gene Expression Profiling of MicroRNAs in HPV-Induced Warts and Normal Skin

: Infection with the human papillomavirus (HPV) is a common occurrence among the global population, with millions of new cases emerging on an annual basis. Dysregulated microRNA (miRNA) expression is increasingly being identified to play a role in a number of different diseases, especially in the context of high-risk HPV infection. The present study investigated the miRNA expression profiles of warts induced by low-risk HPV. In warts, miR-27b, miR-24-1, miR-3654, miR-647, and miR-1914 were downregulated while miR-612 was upregulated compared to normal skin. Using miRTargetLink Human, experimentally supported evidence was obtained showing that miR-27b targeted the vascular endothelial growth factor C (VEGFC) and CAMP-responsive element binding protein 1 (CREB1) genes. The VEGFC and CREB1 genes have been reported to be involved in tumorigenesis and wart formation, respectively. Similarly, the oxidized low-density lipoprotein receptor 1 (OLR1) gene, which plays an important role in the humoral immunity of the skin, and the plexin D1 (PLXND1) gene, which is highly expressed in tumor vasculature, were both found to be common targets of miR-27b, miR-1914, and miR-612.

Upregulated microRNA-106a Promotes Porcine Preadipocyte Proliferation and Differentiation by Targeting Different Genes

Adipose tissue is one of the main organs for the energy storage and supply of organisms. Adipose deposition and metabolism are controlled by a cascade of transcription factors and epigenetic regulatory mechanisms. Previous studies have also shown that miR-106a plays a considerable role in the development of organisms. The regulatory mechanism of miR-106a on porcine preadipocytes is still not clear. In this study, preadipocytes were isolated from the neck subcutaneous deposits of 3–5-day old Chinese native Guanzhong black pigs using 5-ethynyl-20-deoxyuridine (EdU) staining and a CCK-8 assay to detect the number of proliferous cells and real-time qPCR (RT-qPCR) and western blot analysis to detect gene expression, as well as Oil Red O and BODIPY staining dye lipid droplets and flow cytometry (FCM) to detect cell cycles. We also used the double luciferase method to detect the relative luciferase activities. Upregulated miR-106a increased the number of proliferous cells and enhanced the expression of cell proliferation-related genes in porcine adipocytes. The double luciferase reporter vector confirmed that p21 was a target gene of miR-106a in the cell proliferation phase. miR-106a upregulation increased the number of lipid droplets and the expression of lipogenic genes and directly targeted BMP and activin membrane-bound inhibitor (BAMBI) in the process of differentiation. Our results indicated that miR-106a promotes porcine preadipocyte proliferation and differentiation by targeting p21 and BAMBI.

Are innovation and new technologies in precision medicine paving a new era in patients centric care?

Healthcare is undergoing a transformation, and it is imperative to leverage new technologies to generate new data and support the advent of precision medicine (PM). Recent scientific breakthroughs and technological advancements have improved our understanding of disease pathogenesis and changed the way we diagnose and treat disease leading to more precise, predictable and powerful health care that is customized for the individual patient. Genetic, genomics, and epigenetic alterations appear to be contributing to different diseases. Deep clinical phenotyping, combined with advanced molecular phenotypic profiling, enables the construction of causal network models in which a genomic region is proposed to influence the levels of transcripts, proteins, and metabolites. Phenotypic analysis bears great importance to elucidat the pathophysiology of networks at the molecular and cellular level. Digital biomarkers (BMs) can have several applications beyond clinical trials in diagnostics-to identify patients affected by a disease or to guide treatment. Digital BMs present a big opportunity to measure clinical endpoints in a remote, objective and unbiased manner. However, the use of "omics" technologies and large sample sizes have generated massive amounts of data sets, and their analyses have become a major bottleneck requiring sophisticated computational and statistical methods. With the wealth of information for different diseases and its link to intrinsic biology, the challenge is now to turn the multi-parametric taxonomic classification of a disease into better clinical decision-making by more precisely defining a disease. As a result, the big data revolution has provided an opportunity to apply artificial intelligence (AI) and machine learning algorithms to this vast data set. The advancements in digital health opportunities have also arisen numerous questions and concerns on the future of healthcare practices in particular with what regards the reliability of AI diagnostic tools, the impact on clinical practice and vulnerability of algorithms. AI, machine learning algorithms, computational biology, and digital BMs will offer an opportunity to translate new data into actionable information thus, allowing earlier diagnosis and precise treatment options. A better understanding and cohesiveness of the different components of the knowledge network is a must to fully exploit the potential of it.

Dynamic decreased expression and hypermethylation of secreted frizzled-related protein 1 and 4 over the course of pulmonary fibrosis in mice

Aberrantly activated Wnt signaling pathway and dysregulation of extracellular antagonists of Wnt signaling have been revealed in pulmonary fibrosis. In this study we evaluated the expression of secreted frizzled-related proteins (SFRPs) and their aberrant promoter methylation to investigate the involvement of epigenetic regulation in pulmonary fibrosis. The pulmonary fibrosis induced by intratracheal injection of bleomycin (BLM) into mice was adopted. The transcription and relative protein expression of SFRPs were detected at Day 7 (D7), D14, and D21. DNA methylation analysis was performed by methylation-specific polymerase chain reaction (MSP). A DNA methyltransferase (DNMT) inhibitor (5-aza-2'-deoxycytidine; 5-aza) was used for demethylation and the relative β-catenin expression levels were measured to assess overactivity of the canonical Wnt signaling pathway. The transcription and protein expression of SFRP1 significantly decreased at D14 and D21, whereas the transcription and protein expression of SFRP4 significantly decreased at D7 and stayed downregulated until D21. The significantly hypermethylated promoters of SFRP1 and SFRP4 resulted in impaired transcription and decreased expression during pulmonary fibrosis in mice. Besides, reactivation of SFRP1 and SFRP4 by 5-aza reduced β-catenin mRNA and protein expression in vivo and in vitro. Animal experiments confirmed that 5-aza could significantly alleviate bleomycin-induced pulmonary fibrosis in mice. Thus, changes of promoter hypermethylation might downregulate SFRP1 and SFRP4 at different stages of pulmonary fibrosis, and the finding supports the usefulness of DNMT inhibitors, which might effectively reverse activation of β-catenin and reduce pulmonary fibrosis in mice. These data provide a possible new direction in the research on pulmonary fibrosis treatments.

Predicting and understanding the response to short-term intensive insulin therapy in people with early type 2 diabetes

OBJECTIVE

Short-term intensive insulin therapy (IIT) early in the course of type 2 diabetes acutely improves beta-cell function with long-lasting effects on glycemic control. However, conventional measures cannot determine which patients are better suited for IIT, and little is known about the molecular mechanisms determining response. Therefore, this study aimed to develop a model that could accurately predict the response to IIT and provide insight into molecular mechanisms driving such response in humans.

METHODS

Twenty-four patients with early type 2 diabetes were assessed at baseline and four weeks after IIT, consisting of basal detemir and premeal insulin aspart. Twelve individuals had a beneficial beta-cell response to IIT (responders) and 12 did not (nonresponders). Beta-cell function was assessed by multiple methods, including Insulin Secretion-Sensitivity Index-2. MicroRNAs (miRNAs) were profiled in plasma samples before and after IIT. The response to IIT was modeled using a machine learning algorithm and potential miRNA-mediated regulatory mechanisms assessed by differential expression, correlation, and functional network analyses (FNA).

RESULTS

Baseline levels of circulating miR-145-5p, miR-29c-3p, and HbA1c accurately (91.7%) predicted the response to IIT (OR = 121 [95% CI: 6.7, 2188.3]). Mechanistically, a previously described regulatory loop between miR-145-5p and miR-483-3p/5p, which controls TP53-mediated apoptosis, appears to also occur in our study population of humans with early type 2 diabetes. In addition, significant (fold change > 2, P < 0.05) longitudinal changes due to IIT in the circulating levels of miR-138-5p, miR-192-5p, miR-195-5p, miR-320b, and let-7a-5p further characterized the responder group and significantly correlated (|r| > 0.4, P < 0.05) with the changes in measures of beta-cell function and insulin sensitivity. FNA identified a network of coordinately/cooperatively regulated miRNA-targeted genes that potentially drives the IIT response through negative regulation of apoptotic processes that underlie beta cell dysfunction and concomitant positive regulation of proliferation.

CONCLUSIONS

Responses to IIT in people with early type 2 diabetes are associated with characteristic miRNA signatures. This study represents a first step to identify potential responders to IIT (a current limitation in the field) and provides important insight into the pathophysiologic determinants of the reversibility of beta-cell dysfunction. ClinicalTrial.gov identifier: NCT01270789.

Inflammatory Microenvironment and Adipogenic Differentiation in Obesity: The Inhibitory Effect of Theobromine in a Model of Human Obesity In Vitro

Objective

Obesity is considered a clinic condition characterized by a state of chronic low-grade inflammation. The role of macrophages and adipocytokines in adipose tissue inflammation is in growing investigation. The physiopathological mechanisms involved in inflammatory state in obesity are not fully understood though the adipocytokines seem to characterize the biochemical link between obesity and inflammation. The aim of this work is to analyze the effect of theobromine, a methylxanthine present in the cocoa, on adipogenesis and on proinflammatory cytokines evaluated in a model of fat tissue inflammation in vitro.

Methods

In order to mimic in vitro this inflammatory condition, we investigated the interactions between human-like macrophages U937 and human adipocyte cell lines SGBS. The effect of theobromine on in vitro cell growth, cell cycle, adipogenesis, and cytokines release in the supernatants has been evaluated.

Results

Theobromine significantly inhibits the differentiation of preadipocytes in mature adipocytes and reduces the levels of proinflammatory cytokines as MCP-1 and IL-1β in the supernatants obtained by the mature adipocytes and macrophages interaction.

Conclusion

Theobromine reduces adipogenesis and proinflammatory cytokines; these data suggest its potential therapeutic effect for treating obesity by control of macrophages infiltration in adipose tissue and inflammation.

MicroRNAs and other non-coding RNAs in adipose tissue and obesity: emerging roles as biomarkers and therapeutic targets

Obesity is a metabolic condition usually accompanied by insulin resistance (IR), type 2 diabetes (T2D), and dyslipidaemia, which is characterised by excessive fat accumulation and related to white adipose tissue (WAT) dysfunction. Enlargement of WAT is associated with a transcriptional alteration of coding and non-coding RNAs (ncRNAs). For many years, big efforts have focused on understanding protein-coding RNAs and their involvement in the regulation of adipocyte physiology and subsequent role in obesity. However, diverse findings have suggested that a dysfunctional adipocyte phenotype in obesity might be also dependent on specific alterations in the expression pattern of ncRNAs, such as miRNAs. The aim of this review is to update current knowledge on the physiological roles of miRNAs and other ncRNAs in adipose tissue function and their potential impact on obesity. Therefore, we examined their regulatory role on specific WAT features: adipogenesis, adipokine secretion, inflammation, glucose metabolism, lipolysis, lipogenesis, hypoxia and WAT browning. MiRNAs can be released to body fluids and can be transported (free or inside microvesicles) to other organs, where they might trigger metabolic effects in distant tissues, thus opening new possibilities to a potential use of miRNAs as biomarkers for diagnosis, prognosis, and personalisation of obesity treatment. Understanding the role of miRNAs also opens the possibility of using these molecules on individualised dietary strategies for precision weight management. MiRNAs should be envisaged as a future therapeutic approach given that miRNA levels could be modulated by synthetic molecules (f.i. miRNA mimics and inhibitors) and/or specific nutrients or bioactive compounds.

"Beige" Cross Talk Between the Immune System and Metabolism

With thymic senescence the epithelial network shrinks to be replaced by adipose tissue. Transcription factor TBX-1 controls thymus organogenesis, however, the same TBX-1 has also been reported to orchestrate beige adipose tissue development. Given these different roles of TBX-1, we have assessed if thymic TBX-1 expression persists and demonstrates this dualism during adulthood. We have also checked whether thymic adipose involution could yield beige adipose tissue. We have used adult mouse and human thymus tissue from various ages to evaluate the kinetics of TBX-1 expression, as well as mouse (TEP1) and human (1889c) thymic epithelial cells (TECs) for our studies. Electron micrographs show multi-locular lipid deposits typical of beige adipose cells. Histology staining shows the accumulation of neutral lipid deposits. qPCR measurements show persistent and/or elevating levels of beige-specific and beige-indicative markers (TBX-1, EAR-2, UCP-1, PPAR-gamma). We have performed miRNome profiling using qPCR-based QuantStudio platform and amplification-free NanoString platform. We have observed characteristic alterations, including increased miR21 level (promoting adipose tissue development) and decreased miR34a level (bias toward beige adipose tissue differentiation). Finally, using the Seahorse metabolic platform we have recorded a metabolic profile (OCR/ECAR ratio) indicative of beige adipose tissue. In summary, our results support that thymic adipose tissue emerging with senescence is bona fide beige adipose tissue. Our data show how the borders blur between a key immune tissue (the thymus) and a key metabolic tissue (beige adipose tissue) with senescence. Our work contributes to the understanding of cross talk between the immune system and metabolism.