Effects of Pituitary Adenylate Cyclase Activating Polypeptide in Human Proximal Tubule Cells Against Gentamicin Toxicity

Nephrotoxicity by aminoglycoside antibiotics is a common cause of drug-induced nephropathy. Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide first isolated from hypothalamus, but later shown in widespread distribution. It exerts general cytoprotective effects in different cell types. Renoprotective effects of PACAP have been shown in various in vivo and in vitro experiments, but it is still not known whether it protects human proximal tubular cells against gentamicin toxicity. The aim of the present study was to investigate whether PACAP could influence the survival rate of human proximal tubular epithelial cells exposed to gentamicin treatment. For investigating its effect on cell survival after gentamicin treatment, cell viability was evaluated using MTT assay. Obtaining further insight into the background mechanism of gentamicin exposure and PACAP’s effect, expression of numerous kidney-related proteins was investigated using kidney biomarker array. Our results show that PACAP had protective effects against gentamicin-induced decreased cell viability, while it did not influence the proliferation activity of HK-2 cells. PACAP could counteract the expression-decreasing effect of gentamicin on dipeptidyl peptidase IV and vascular endothelial growth factor as assessed by kidney biomarker array. In summary, our present study could prove the protective effect of exogenous PACAP in gentamicin-induced nephrotoxicity.