The molecular mechanisms by which vitamin D improve glucose homeostasis: A mechanistic review.

Diabetes mellitus (DM) is a complex metabolic disorder involving multiple deleterious molecular pathways and cellular defects leading to disturbance in the biologic milieu. It is currently a global health concern with growing incidence, especially among younger adults. There is an unmet need to find new therapeutic targets for the management of diabetes. Vitamin D is a promising target in the pathophysiology of DM, especially since vitamin D deficiency is common in patients with diabetes compared to people without diabetes. Evidence suggests that it can play significant roles in improving peripheral insulin sensitivity and glucose metabolism, however, the exact pathophysiological mechanism is not clarified yet. In this current study, we have reviewed the evidence on the effect of vitamin D in improving insulin resistance via distinct molecular pathways.

MicroRNAs and type 2 diabetes mellitus: Molecular mechanisms and the effect of antidiabetic drug treatment.

The incidence of type 2 diabetes mellitus (T2DM), the most prevalent metabolic disease, is rapidly growing worldwide. T2DM has several underlying causes involved in its development. In recent decades, there is compelling evidence demonstrating that microRNAs (miRs) are implicated in the pathophysiology of T2DM. miRs are small non-coding RNAs which serve as endogenous gene regulators by binding to specific sequences in RNA and modifying gene expression toward up- or down-regulation. T2DM occurrence and complications may be influenced by increasing or decreasing the activity of some miRs. In the present narrative review, we comment on four molecular pathways/mechanisms that mediate the link between T2DM and different forms of miRs. These mechanisms include involvement of miRs in beta cells development, insulin sensitivity/resistance, insulin production/secretion and insulin signaling. The effects of antidiabetic drugs on miRs are also discussed.