Where are we now in diabetic research?

Abstract

Diabetes along with obesity has emerged as a silent epidemic worldwide owing to sedentary lifestyle and high calorie diets. This is certainly the case in Korea, where diabetes and pre-diabetes (impaired fasting glucose) accounted for 10.1 and 19.9 % of the population aged over 30 years or older, respectively, in 2010 (Diabetes Fact Sheet in Korea 2012). Likewise, in the United States, diabetes accounted for 25.8 million children and adults, 8.3 % of the population in 2010 (National Diabetes Fact Sheet 2011, USA). The physical and economic burden of diabetes to both the patient and society are enormous. Current anti-diabetic drugs with different mode of action have limited effectiveness and tolerability, and diabetic patients under current treatment modality will progress to microand macro-vascular complications. The prevalence of diabetes is predicted to rise continuously, and more people will experience diabetic complications unless new and more effective therapeutic and preventive measures become available. A large body of information has accumulated and important progress has been made in the last decade in our understanding of molecular mechanisms involved in the development and progression of insulin resistance, insulin secretion (b-cell function), and diabetic complications. These include autophagy, endoplasmic reticulum (ER) stress, metabolic sensors, abnormalities in metabolites formation and transcriptional machinery associated with glucose/lipid toxicity, dysregulation of adipokines, and chronic low grade inflammation. In addition, the discovery of microRNAs (miRNAs), short single-stranded RNA molecules comprising about 1 % of the genome and regulating target mRNA translational repression or cleavage, has increased our understanding on the pathogenesis of diabetes and its complications. Considering that diabetes has a strong genetic predisposition, the availability of genome-wide association (GWA) and exome sequencing studies will certainly improve our insights on genetics of diabetes and its complications. It is true, however, that effective treatment of diabetes and prevention of diabetic complications remain elusive goals. For future direction of research in diabetes to achieve a more effective correction of intracellular metabolic errors through exploration of new therapeutic targets, it is appropriate that we review current status of research in diabetic research. This special issue starts from the review by Cheon (2013), which provides the latest information about the novel molecular targets of type 2 diabetes mellitus (T2DM) pathogenesis and current development status of new T2DM therapeutics (Cheon 2013). Particularly, it highlights new therapeutic approaches, including incretin-based therapy, renal tubular glucose transporter inhibitors, b-hydroxysteroid dehydrogenase 1 inhibitors, peroxisome proliferator-activated receptor modulators, regulators of glucose/ lipid metabolism, and anti-inflammatory therapies. The next series of reviews deal with novel pathophysiological mechanisms of T2DM as an intension to seek for the novel therapeutic strategy. The second article by Lee (2013) and colleagues provides reviews on recent findings related to the roles of miRNAs in T2DM (Park et al. 2013a). The M.-K. Kwak College of Pharmacy, The Catholic University of Korea, Gyeonggi-do, Bucheon, South Korea e-mail: mkwak@catholic.ac.kr