It is acknowledged that contrast-induced nephropathy (CIN) is a common cause of acute renal insufficiency after cardiac catheterization and affects mortality and morbidity. To date, it is unknown whether oral N-acetylcysteine (NAC) is able to prevent contrast-induced nephropathy (CIN) in patients undergoing coronary angioplasty. A meta-analysis of randomized controlled trials was performed to assess the effects of NAC in the prevention of CIN in patients following coronary angioplasty. A total of 19 studies published prior to January 2015 that investigated the efficacy of oral NAC for the prevention of CIN were collected from Medline, Cochrane and Embase databases and conference proceedings from cardiology and nephrology meetings. The primary point of investigation was CIN, and the secondary points were renal failure requiring dialysis, mortality and length of hospitalization. The meta-analysis was performed using fixed- or random-effect models according to heterogeneity. Up to January 2015, 19 randomized placebo-controlled clinical trials met the inclusion criteria for the meta-analysis, including 4,514 patients. The pooled data showed that oral NAC did not reduce the CIN incidence [relative risk 0.84, 95% confidence interval (CI) 0.65–1.10; P=0.20], without heterogeneity among trials (I2=29%). Thus, the present meta-analysis suggests that oral NAC therapy is not effective as an alternative treatment to prevent CIN in patients following angioplasty. Further high quality randomized clinical controlled trials are required to confirm the usage and availability of this treatment.

The major cause of diabetes-related mortality is the complications involving aberrant angiogenesis. To understand the underlying mechanisms of such altered-angiogenesis in diabetes, examining the interaction between endothelial cells (ECs) and neighboring smooth muscle cells (VSMCs) rather than mainly focusing on EC might provide us useful information. Thus, in the present study, we examined the effect of high glucose on the expression of Jag1, one of the key trans-activating ligands of Notch receptors known to be involved in EC-SMC interaction, as well as angiogenic process, in vascular smooth muscle cells (VSMCs) to elucidate possible role of EC-VSMC interaction in diabetes-related angiopathy. Our data indicate that high glucose condition decreases the expression of Jag1 in VSMCs possibly by increasing Jag1-targeting micro RNAs (miRNAs) such as miR-21, and exogenous Jag1-simulating peptides increase proliferation and migration of ECs under high glucose condition in vitro. Ex vivo study using aortic rings from normal and streptozotocin (STZ)-treated diabetic mouse demonstrated that exogenous Jag1-simulating peptides increases EC sprouting of aortic rings from diabetic mouse under high glucose condition. Our data suggest that EC-VSMC interaction is altered under high glucose condition and restoring EC-VSMC interaction can be a feasible therapeutic target for treating diabetes-related angiopathy.

No abstract