TY - JOUR A1 - Hocher, Berthold A1 - Reichetzeder, Christoph A1 - Alter, Markus L. T1 - Renal and cardiac effects of DPP-4 inhibitors - from preclinical development to clinical research JF - Kidney & blood pressure research : official organ of the Gesellschaft für Nephrologie N2 - Inhibitors of type 4 dipeptidyl peptidase (DDP-4) were developed and approved for the oral treatment of type 2 diabetes. Its mode of action is to inhibit the degradation of incretins, such as type 1 glucagon like peptide (GLP-1), and GIP. GLP-1 stimulates glucose-dependent insulin secretion from pancreatic beta-cells and suppresses glucagon release from alpha-cells, thereby improving glucose control. Besides its action on the pancreas type 1 glucagon like peptide has direct effects on the heart, vessels and kidney mainly via the type 1 glucagon like peptide receptor (GLP-1R). Moreover, there are substrates of DPP-4 beyond incretins that have proven renal and cardiovascular effects such as BNP/ANP, NPY, PYY or SDF-1 alpha. Preclinical evidence suggests that DPP-4 inhibitors may be effective in acute and chronic renal failure as well as in cardiac diseases like myocardial infarction and heart failure. Interestingly, large cardiovascular meta-analyses of combined Phase II/III clinical trials with DPP-4 inhibitors point all in the same direction: a potential reduction of cardiovascular events in patients treated with these agents. A pooled analysis of pivotal Phase III, placebo-controlled, registration studies of linagliptin further showed a significant reduction of urinary albumin excretion after 24 weeks of treatment. The observation suggests direct renoprotective effects of DPP-4 inhibition that may go beyond its glucose-lowering potential. Type 4 dipeptidyl peptidase inhibitors have been shown to be very well tolerated in general, but for those excreted via the kidney dose adjustments according to renal function are needed to avoid side effects. In conclusion, the direct cardiac and renal effects seen in preclinical studies as well as meta-analysis of clinical trials may offer additional potentials - beyond improvement of glycemic control - for this newer class of drugs, such as acute kidney failure, chronic kidney failure as well as acute myocardial infarction and heart failure. KW - DDP-4 inhibition KW - Diabetes KW - GLP-1 KW - Cardiovascular effects KW - Myocardial infarction KW - Kidney KW - Diabetic nephropathy KW - Acute renal failure Y1 - 2012 U6 - https://doi.org/10.1159/000339028 SN - 1420-4096 VL - 36 IS - 1 SP - 65 EP - 84 PB - Karger CY - Basel ER - TY - JOUR A1 - Dschietzig, Thomas Bernd A1 - Krause-Relle, Katharina A1 - Hennequin, Maud A1 - von Websky, Karoline A1 - Rahnenfuhrer, Jan A1 - Ruppert, Jana A1 - Groena, Hans Juergen A1 - Armbruster, Franz Paul A1 - Bathgate, Ross A. D. A1 - Aschenbach, Joerg R. A1 - Forssmann, Wolf-Georg A1 - Hocher, Berthold T1 - Relaxin-2 does not Ameliorate Nephropathy in an experimental model of Type-1 Diabetes JF - Kidney & blood pressure research : official organ of the Gesellschaft für Nephrologie N2 - Background/Aims: In diabetic nephropathy (DN), the current angiotensin-II-blocking pharmacotherapy is frequently failing. For diabetic cardiomyopathy (DC), there is no specific remedy available. Relaxin-2 (Rlx) - an anti-fibrotic, anti-inflammatory, and vasoprotecting peptide - is a candidate drug for both. Methods: Low-dose (32 mu g/kg/day) and high-dose (320 mu g/kg/day) Rlx were tested against vehicle (n = 20 each) and non-diabetic controls (n = 14) for 12 weeks in a model of type-1 diabetes induced in endothelial nitric oxide synthase knock-out (eNOS-KO) mice by intraperitoneal injection of streptozotocin. Results: Diabetic animals showed normal plasma creatinine, markedly increased albuminuria and urinary malonyldialdehyde, elevated relative kidney weight, glomerulosclerosis, and increased glomerular size, but no relevant interstitial fibrosis. Neither dose of Rlx affected these changes although the drug was active and targeted plasma levels were achieved. Of note, we found no activation of the renal TGF-beta pathway in this model. In the hearts of diabetic animals, no fibrotic alterations indicative of DC could be determined which precluded testing of the initial hypothesis. Conclusions: We investigated a model showing early DN without overt tubulo-interstitial fibrosis and activation of the TGF-beta-Smad-2/3 pathway. In this model, Rlx proved ineffective; however, the same may not apply to other models and types of diabetes. KW - Diabetic nephropathy KW - Diabetic cardiomyopathy KW - Fibrosis KW - Inflammation KW - Relaxin Y1 - 2015 U6 - https://doi.org/10.1159/000368484 SN - 1420-4096 SN - 1423-0143 VL - 40 IS - 1 SP - 77 EP - 88 PB - Karger CY - Basel ER - TY - JOUR A1 - Alter, Markus L. A1 - Ott, Ina M. A1 - von Websky, Karoline A1 - Tsuprykov, Oleg A1 - Sharkovska, Yuliya A1 - Krause-Relle, Katharina A1 - Raila, Jens A1 - Henze, Andrea A1 - Klein, Thomas A1 - Hocher, Berthold T1 - DPP-4 Inhibition on top of angiotensin receptor blockade offers a new therapeutic approach for diabetic nephropathy JF - Kidney & blood pressure research : official organ of the Gesellschaft für Nephrologie N2 - Background: The need for an improved treatment for diabetic nephropathy is greatest in patients who do not adequately respond to angiotensin II receptor blockers (ARBs). This study investigated the effect of the novel dipeptidyl peptidase-4 inhibitor linagliptin alone and in combination with the ARB telmisartan on the progression of diabetic nephropathy in diabetic endothelial nitric oxide synthase (eNOS) knockout mice. Methods: Sixty male eNOS knockout C57BL/6J mice were divided into four groups after receiving intraperitoneal high-dose streptozotocin: telmisartan (1 mg/kg), linagliptin (3 mg/kg), linagliptin + telmisartan (3 mg/kg + 1 mg/kg) and vehicle. Fourteen mice were used as non-diabetic controls. Results: After 12 weeks, urine and blood were obtained and blood pressure measured. Glucose concentrations were increased and similar in all diabetic groups. Telmisartan alone reduced systolic blood pressure by 5.9 mmHg versus diabetic controls (111.2 +/- 2.3 mmHg vs 117.1 +/- 2.2 mmHg; mean +/- SEM; P = 0.071). Combined treatment significantly reduced albuminuria compared with diabetic controls (71.7 +/- 15.3 mu g/24 h vs 170.8 +/- 34.2 mu g/24 h; P = 0.017), whereas the effects of single treatment with either telmisartan (97.8 +/- 26.4 mu g/24 h) or linagliptin (120.8 +/- 37.7 mu g/24 h) were not statistically significant. DPP-4 inhibition, alone and in combination, led to significantly lower plasma osteopontin levels compared with telmisartan alone. Histological analysis revealed reduced glomerulosclerosis after Linagliptin alone and in combination with telmisartan in comparison to non treated diabetic animals (p < 0.01 and p < 0.05). Kidney malonaldehyde immune-reactivity, a marker of oxidative stress, was significantly lower in animals treated with linagliptin. Conclusions: DPP-4 inhibition on top of ARB treatment significantly reduced urinary albumin excretion and oxidative stress in diabetic eNOS knockout mice. Linagliptin on top of an angiotensin II receptor blocker may offer a new therapeutic approach for patients with diabetic nephropathy. KW - Diabetic nephropathy KW - DPP-4 inhibitor KW - Linagliptin KW - Renin-angiotensin system Y1 - 2012 U6 - https://doi.org/10.1159/000341487 SN - 1420-4096 VL - 36 IS - 1 SP - 119 EP - 130 PB - Karger CY - Basel ER -