The chemoprotective effect of Piperine on cisplatin‐induced apoptosis in auditory cells

Abstract

Piperine is a major component of black pepper, Piper nigrum Linn, used widely in traditional medicine. In this study, we examined whether piperine could protect HEI‐OC1 cells against cisplatin‐induced apoptosis through the induction of heme oxygenase‐1 (HO‐1) expression. Piperine induced the expression of HO‐1 in dose‐ and time‐dependent manner. Piperine also induced ARE‐luciferase and translocated Nrf2 to nucleus. Piperine activated the JNK, ERK, and p38 mitogen‐activated protein kinases (MAPKs) pathways, and the JNK pathway played an important role in piperine‐induced HO‐1 expression. Piperine protected the cells against cisplatin‐induced apoptosis. The protective effect of piperine was abrogated by zinc protoporphyrin IX (ZnPP IX), a HO inhibitor, and antisense oligdeoxynuceotides (ODN) against HO‐1 gene. These results demonstrate that the expression of HO‐1 by piperine is mediated by both JNK pathway and Nrf2, and the expression inhibits cisplatin‐induced apoptosis in HEI‐OC1 cells.