TY - JOUR A1 - von Websky, Karoline A1 - Reichetzeder, Christoph A1 - Hocher, Berthold T1 - Physiology and pathophysiology of incretins in the kidney JF - Current opinion in nephrology and hypertension : reviews of all advances, evaluations of key references, comprehensive listing of papers N2 - Purpose of reviewIncretin-based therapy with glucagon-like peptide-1 receptor (GLP-1R) agonists and dipeptidyl peptidase-4 (DPP-4) inhibitors is considered a promising therapeutic option for type 2 diabetes mellitus. Cumulative evidence, mainly from preclinical animal studies, reveals that incretin-based therapies also may elicit beneficial effects on kidney function. This review gives an overview of the physiology, pathophysiology, and pharmacology of the renal incretin system.Recent findingsActivation of GLP-1R in the kidney leads to diuretic and natriuretic effects, possibly through direct actions on renal tubular cells and sodium transporters. Moreover, there is evidence that incretin-based therapy reduces albuminuria, glomerulosclerosis, oxidative stress, and fibrosis in the kidney, partially through GLP-1R-independent pathways. Molecular mechanisms by which incretins exert their renal effects are understood incompletely, thus further studies are needed.SummaryThe GLP-1R and DPP-4 are expressed in the kidney in various species. The kidney plays an important role in the excretion of incretin metabolites and most GLP-1R agonists and DPP-4 inhibitors, thus special attention is required when applying incretin-based therapy in renal impairment. Preclinical observations suggest direct renoprotective effects of incretin-based therapies in the setting of hypertension and other disorders of sodium retention, as well as in diabetic and nondiabetic nephropathy. Clinical studies are needed in order to confirm translational relevance from preclinical findings for treatment options of renal diseases. KW - DDP-4 inhibition KW - diabetes KW - diabetic nephropathy KW - GLP-1 receptor KW - hypertension KW - incretins KW - kidney KW - renal impairment Y1 - 2014 U6 - https://doi.org/10.1097/01.mnh.0000437542.77175.a0 SN - 1062-4821 SN - 1473-6543 VL - 23 IS - 1 SP - 54 EP - 60 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Nair, Anil V. A1 - Hocher, Berthold A1 - Verkaart, Sjoerd A1 - van Zeeland, Femke A1 - Pfab, Thiemo A1 - Slowinski, Torsten A1 - Chen, You-Peng A1 - Schlingmann, Karl Peter A1 - Schaller, Andre A1 - Gallati, Sabina A1 - Bindels, Rene J. A1 - Konrad, Martin A1 - Hönderop, Joost G. T1 - Loss of insulin-induced activation of TRPM6 magnesium channels results in impaired glucose tolerance during pregnancy JF - Proceedings of the National Academy of Sciences of the United States of America N2 - Hypomagnesemia affects insulin resistance and is a risk factor for diabetes mellitus type 2 (DM2) and gestational diabetes mellitus (GDM). Two single nucleotide polymorphisms (SNPs) in the epithelial magnesium channel TRPM6 ((VI)-I-1393, (KE)-E-1584) were predicted to confer susceptibility for DM2. Here, we show using patch clamp analysis and total internal reflection fluorescence microscopy, that insulin stimulates TRPM6 activity via a phosphoinositide 3-kinase and Rac1-mediated elevation of cell surface expression of TRPM6. Interestingly, insulin failed to activate the genetic variants TRPM6 ((VI)-I-1393) and TRPM6((KE)-E-1584), which is likely due to the inability of the insulin signaling pathway to phosphorylate TRPM6(T-1391) and TRPM6(S-1583). Moreover, by measuring total glycosylated hemoglobin (TGH) in 997 pregnant women as a measure of glucose control, we demonstrate that TRPM6((VI)-I-1393) and TRPM6((KE)-E-1584) are associated with higher TGH and confer a higher likelihood of developing GDM. The impaired response of TRPM6((VI)-I-1393) and TRPM6((KE)-E-1584) to insulin represents a unique molecular pathway leading to GDM where the defect is located in TRPM6. KW - kidney KW - distal convoluted tubule KW - transient receptor potential KW - vesicular trafficking Y1 - 2012 U6 - https://doi.org/10.1073/pnas.1113811109 SN - 0027-8424 VL - 109 IS - 28 SP - 11324 EP - 11329 PB - National Acad. of Sciences CY - Washington ER -