Diabetic nephropathy in 2014: improved cardiorenal prognosis in diabetic nephropathy

Randomized trial of an intensified, multifactorial intervention in patients with advanced-stage diabetic kidney disease: Diabetic Nephropathy Remission and Regression Team Trial in Japan (DNETT-Japan)

AIMS/INTRODUCTION

We evaluated the efficacy of multifactorial intensive treatment (IT) on renal outcomes in patients with type 2 diabetes and advanced-stage diabetic kidney disease (DKD).

MATERIALS AND METHODS

The Diabetic Nephropathy Remission and Regression Team Trial in Japan (DNETT-Japan) is a multicenter, open-label, randomized controlled trial with a 5-year follow-up period. We randomly assigned 164 patients with advanced-stage diabetic kidney disease (urinary albumin-to-creatinine ratio ≥300 mg/g creatinine, serum creatinine level 1.2-2.5 mg/dL in men and 1.0-2.5 mg/dL in women) to receive either IT or conventional treatment. The primary composite outcome was end-stage kidney failure, doubling of serum creatinine or death from any cause, which was assessed in the intention-to-treat population.

RESULTS

The IT tended to reduce the risk of primary end-points as compared with conventional treatment, but the difference between treatment groups did not reach the statistically significant level (hazard ratio 0.69, 95% confidence interval 0.43-1.11; P = 0.13). Meanwhile, the decrease in serum low-density lipoprotein cholesterol level and the use of statin were significantly associated with the decrease in primary outcome (hazard ratio 1.14; 95% confidence interval 1.05-1.23, P < 0.001 and hazard ratio 0.53, 95% confidence interval 0.28-0.998, P < 0.05, respectively). The incidence of adverse events was not different between treatment groups.

CONCLUSIONS

The risk of kidney events tended to decrease by IT, although it was not statistically significant. Lipid control using statin was associated with a lower risk of adverse kidney events. Further follow-up study might show the effect of IT in patients with advanced diabetic kidney disease.

NGAL and SMAD1 gene expression in the early detection of diabetic nephropathy by liquid biopsy

INTRODUCTION

Diabetic nephropathy (DN) is a disease that progresses with the slow and progressive decline of the glomerular filtration rate (GFR); the installation of this pathology is silent and one of the major causes of death in patients with diabetes.

AIMS

To identify new molecular biomarkers for early identification of the onset of DN in patients with type II diabetes mellitus (DM2). We studied the expression profile of the genes; suppressor of mothers against decapentaplegic type 1 (SMAD1), neutrophil gelatinase-associated lipocalin (NGAL) and type IV collagen (COLIV1A) in peripheral blood and urine sediment samples.

METHODS

Ninety volunteers, 51 with DM2 and 39 healthy, were recruited from the Faculdade de Medicina do ABC outpatient clinic. We conducted an interview and collected anthropometric data, as well as blood and urine samples for biochemical evaluation and real-time PCR amplification of the genes of interest.

RESULTS

Gene expression data: peripheral blood NGAL (DM2 0.09758±0.1914 vs CTL 0.02293±0.04578), SMAD1 (blood: DM2 0.01102±0.04059* vs CTL 0.0001317±0.0003609; urine: DM2 0.7195±2.344* vs CTL 0.09812±0.4755), there was no significant expression of COLIV1A. These genes demonstrated good sensitivity and specificity in the receiving operating characteristic curve evaluation.

CONCLUSION

Our data suggest the potential use of NGAL and SMAD1 gene expression in peripheral blood and urine samples as early biomarkers of DN.

Addition of cyclic angiotensin-(1-7) to angiotensin-converting enzyme inhibitor therapy has a positive add-on effect in experimental diabetic nephropathy

The Renin-Angiotensin System (RAS) possesses a counter-regulatory axis composed of angiotensin converting enzyme (ACE)2, angiotensin-(1-7) [Ang-(1-7)] and the Mas receptor, which opposes many AT1-receptor-mediated effects of ligand angiotensin II. Ang-(1-7), as a ligand of the Mas receptor, has inhibitory effects on renal inflammation and fibrosis in experimental diabetes. However, Ang-(1-7) has a short half-life in plasma, which may render it unsuitable for use in clinics. Here, we investigated the effects of the lanthionine-stabilized Ang-(1-7), cyclic (c)Ang-(1-7), a lanthipeptide that is more peptidase-resistant than the linear peptide, in BTBR ob/ob mice with type 2 diabetic nephropathy. BTBR ob/ob mice received vehicle, cAng-(1-7), or the ACE inhibitor lisinopril. The treatment started at ten weeks of age, when the animals had already developed albuminuria, and ended at 19-20 weeks of age. cAng-(1-7) limited albuminuria progression, and limited podocyte dysfunction similarly to lisinopril. cAng-(1-7), unlike lisinopril, reduced glomerular fibrosis and inflammation, and counteracted glomerular capillary rarefaction. Furthermore, when cAng-(1-7) was combined with lisinopril, a superior antiproteinuric effect than with lisinopril alone was found, in association with better preservation of podocyte proteins and amelioration of capillary density. Thus, adding cAng-(1-7) to ACE-inhibitor therapy could benefit those diabetic patients who do not respond completely to ACE-inhibitor therapy.

Diabetes microvascular complications-A clinical update

BACKGROUND

The purpose of this study is to summarise the empirical evidence addressing diabetes microvascular complications and management. The effects of diabetes mellitus include long-term damage, dysfunction and failure of various organs. Microvascular disease tends to occur predominantly in tissues where glucose uptake is independent of insulin activity because these tissues are exposed to glucose levels that correlate very closely with blood glucose levels. These metabolic injuries cause altered blood flow and changes in endothelial permeability, extravascular protein deposition and coagulation resulting in organ dysfunction which in turn lead to microvascular complications.

METHOD

A systematic search of the literature from 2000 to 2016 was conducted using four databases (Medline, Pubmed, Cochrane central and Google scholar) using search terms such as diabetic microvascular complications', pathogenesis, screening, risk factors, pharmacological and non-pharmacological interventions and management.

RESULTS

The current evidence supports a direct relationship between blood pressure (BP) and glycaemic control and progression of nephropathy and retinopathy. These are now considered as independent risk factors for microvascular disease progression. New fields of research addressing new drugs as potential therapeutic targets of the future will be presented.

CONCLUSION

The prevention of microvascular disease involves paying attention to aggravating risk factors and implementing screening programmes to improve early detection.

Atrasentan increased the expression of klotho by mediating miR-199b-5p and prevented renal tubular injury in diabetic nephropathy

Atrasentan is a promising therapy for treating diabetic nephropathy (DN). Here we evaluated whether atrasentan down-regulated the miR-199b-5p expression, thereby increasing klotho and preventing renal tubular injury in DN. One-hundred patients with type 2 diabetes mellitus (T2DM) and 40 healthy subjects were included. A DN mice model was established by an injection of streptozotocin (STZ). Human renal proximal tubular epithelial HK-2 cells were exposed to high glucose (20 mmol/L). Treated the mice and HK-2 cells with atrasentan, and we then investigated whether and how miR-199b-5p and Klotho were involved in preventing renal tubular injury in DN. In patients, the serum miR-199b-5p level increased and the klotho concentration decreased in accordance with elevated albuminuria. Atrasentan down-regulated miR-199b-5p and up-regulated klotho of the DN mice and HK-2 cells exposed to high glucose. High glucose promoted the binding of histone H3 to the miR-199b-5p promoter, and atrasentan canceled this effect. MiR-199b-5p targeted the 3′ UTR of klotho. Overexpression of miR-199b-5p canceled the effects of atrasentan on klotho expression and apoptosis of renal tubular cells in both in vivo and in vitro. The increased serum klotho, mediated by miR-199b-5p, is a possible mechanism by which atrasentan prevents renal tubular injury in DN.