Body fat composition and miR-378 expression profiling in patients with type 1 diabetes

MicroRNA and Diabetic Bone Disease

PURPOSE OF REVIEW

The incidence of diabetes is increasing worldwide. Diabetes mellitus is characterized by hyperglycemia, which in the long-term damages the function of many organs including the eyes, the vasculature, the nervous system, and the kidneys, thereby imposing an important cause of morbidity for affected individuals. More recently, increased bone fragility was also noted in patients with diabetes. While patients with type 1 diabetes mellitus (T1DM) have low bone mass and a 6-fold risk for hip fractures, patients with type 2 diabetes mellitus (T2DM) have an increased bone mass, yet still display a 2-fold elevated risk for hip fractures. Although the underlying mechanisms are just beginning to be unraveled, it is clear that diagnostic tools are lacking to identify patients at risk for fracture, especially in the case of T2DM, in which classical tools to diagnose osteoporosis such as dual X-ray absorptiometry have limitations. Thus, new biomarkers are urgently needed to help identify patients with diabetes who are at risk to fracture.

RECENT FINDINGS

Previously, microRNAs have received great attention not only for being involved in the pathogenesis of various chronic diseases, including osteoporosis, but also for their value as biomarkers. Here, we summarize the current knowledge on microRNAs and their role in diabetic bone disease and highlight recent studies on miRNAs as biomarkers to predict bone fragility in T1DM and T2DM. Finally, we discuss future directions and challenges for their use as prognostic markers.

Perspectives and challenges of epigenetic determinants of childhood obesity: A systematic review

The tremendous increase in childhood obesity prevalence over the last few decades cannot merely be explained by genetics and evolutionary changes in the genome, implying that gene-environment interactions, such as epigenetic modifications, likely play a major role. This systematic review aims to summarize the evidence of the association between epigenetics and childhood obesity. A literature search was performed via PubMed and Scopus engines using a combination of terms related to epigenetics and pediatric obesity. Articles studying the association between epigenetic mechanisms (including DNA methylation and hydroxymethylation, non-coding RNAs, and chromatin and histones modification) and obesity and/or overweight (or any related anthropometric parameters) in children (0-18 years) were included. The risk of bias was assessed with a modified Newcastle-Ottawa scale for non-randomized studies. One hundred twenty-one studies explored epigenetic changes related to childhood obesity. DNA methylation was the most widely investigated mechanism (N = 101 studies), followed by non-coding RNAs (N = 19 studies) with evidence suggestive of an association with childhood obesity for DNA methylation of specific genes and microRNAs (miRNAs). One study, focusing on histones modification, was identified. Heterogeneity of findings may have hindered more insights into the epigenetic changes related to childhood obesity. Gaps and challenges that future research should face are herein described.

Bovine Pre-adipocyte Adipogenesis Is Regulated by bta-miR-150 Through mTOR Signaling

Micro RNA (miR) are recognized for their important roles in biological processes, particularly in regulatory componentization. Among the miR, miR-150 has been the focus of intense scrutiny, mostly due to its role in malignant tumors. A comparison between steer and bull adipose tissues identified bta-miR-150 as one of the nine downregulated miRNAs, although its function remains unknown (GEO:GSE75063). The present study aimed to further characterize the role of bta-miR-150 in cattle. bta-miR-150 has a negative regulatory effect on the differentiation of bovine adipocytes and promotes proliferation. Overexpression of bta-miR-150 can promote mRNA and protein expression of the marker genes CDK1, CDK2, and PCNA, increase the number of EdU-stained cells, promote adipocyte proliferation, inhibit adipocyte differentiation, and reduce lipid droplet formation. Results of RNA-seq and WGCNA analyses showed that the mammalian target of the rapamycin signaling pathway, which plays a major regulatory role, is dysregulated by the overexpression and inhibition of miR-150. We found that the target gene of bta-miR-150 is AKT1 and that bta-miR-150 affects AKT1 phosphorylation levels. These results showed that bta-miR-150 plays a role in adipogenic differentiation and might therefore have applications in the beef industry.

MicroRNA, Diabetes Mellitus and Colorectal Cancer

Diabetes mellitus (DM) is an endocrinological disorder that is due to either the pancreas not producing enough insulin, or the body does not respond appropriately to insulin. There are many complications of DM such as retinopathy, nephropathy, and peripheral neuropathy. In addition to these complications, DM was reported to be associated with different cancers. In this review, we discuss the association between DM and colorectal cancer (CRC). CRC is the third most commonly diagnosed cancer worldwide that mostly affects older people, however, its incidence and mortality are rising among young people. We discuss the relationship between DM and CRC based on their common microRNA (miRNA) biomarkers. miRNAs are non-coding RNAs playing important functions in cell differentiation, development, regulation of cell cycle, and apoptosis. miRNAs can inhibit cell proliferation and induce apoptosis in CRC cells. miRNAs also can improve glucose tolerance and insulin sensitivity. Therefore, investigating the common miRNA biomarkers of both DM and CRC can shed a light on how these two diseases are correlated and more understanding of the link between these two diseases can help the prevention of both DM and CRC.