Improving renoprotective effects by adding piperazine ferulate and angiotensin receptor blocker in diabetic nephropathy: a meta-analysis of randomized controlled trials

Background Piperazine ferulate, a derivative of ferulic acid has been widely used in clinical practice for cardiovascular and kidney diseases in China. The objective of this meta-analysis was to investigate the benefits by adding piperazine ferulate to angiotensin receptor blockers (ARBs) in diabetic nephropathy patients. Methods PubMed, Embase, Cochrane Library, Wangfang, VIP, and CNKI database (until March 17, 2021) were comprehensively searched for randomized controlled trials investigating the effects of adding piperazine ferulate to ARBs in diabetic nephropathy patients. Results Data were retrieved from 14 RCTs involving 1374 patients. When compared with ARBs alone, co-administration of piperazine ferulate and ARBs significantly reduced urinary albumin excretion rate (weighted mean differences [WMD] - 20.32 mu g/min; 95% confidence interval [CI] - 28.45 to - 12.19), 24-h proteinuria (WMD - 91.08 mg; 95% CI - 107.24 to - 74.91), beta 2-microglobulin (standard mean difference [SMD] - 2.07; 95% CI - 2.51 to - 1.63), serum level of creatinine (WMD - 8.39 mu mol/L; 95% CI - 11.87 to - 4.92), fibrinogen (WMD - 0.40 g/L; 95% CI - 0.46 to - 0.33), and plasma viscosity (WMD - 0.56 mPa s; 95% CI - 0.91 to - 0.21). Subgroup analysis showed that the effects of piperazine ferulate on UAER and serum creatinine were stronger in early diabetic nephropathy. However, piperazine ferulate had no significant effects on the serum blood urea nitrogen and fasting blood glucose. Conclusion Adding piperazine ferulate to ARBs may achieve additional renal protective benefits, particular in early diabetic nephropathy patients.