title: Protective effect of tanshinone IIA against radiation-induced ototoxicity in HEI-OC1 cells.
abstract: Radiotherapy is a highly efficient treatment method for nasopharyngeal carcinoma that is often accompanied by significant ototoxic side-effects. The inner ear hair cells are particularly prone to serious injury following radiotherapy. Tanshinone IIA is a transcription factor inhibitor that is extracted from the traditional herbal medicine,Salvia miltiorrhizaBunge. The present study investigated the effects of tanshinone IIA treatment on radiation-induced toxicity in the HEI-OC1 hair cell line. Using an MTT assay and flow cytometry, the radiation-induced weakening of the cells was observed to be alleviated when the cells were pre-treated with tanshinone IIA. Radiation exposure promoted p65/nuclear factor (NF)-κB nuclear translocation and activated the p53/p21 pathway, two processes which play a significant role in radiation-induced cell apoptosis. However, pre-treatment of the cells with tanshinone IIA inhibited p65/NF-κB nuclear translocation and p53/p21 pathway activation. These results demonstrate that tanshinone IIA is capable of protecting cochlear cells from radiation-induced injury through the suppression of p65/NF-κB nuclear translocation and the p53/p21 signaling pathway.
authors.affiliation: Department of Radiation Oncology, Institute of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, P.R. China.
authors.forename: Shasha
authors.initials: S
authors.lastname: DU
authors.forename: Qiwei
authors.initials: Q
authors.lastname: Yao
authors.forename: Peixin
authors.initials: P
authors.lastname: Tan
authors.forename: Guozhu
authors.initials: G
authors.lastname: Xie
authors.forename: Chen
authors.initials: C
authors.lastname: Ren
authors.forename: Quanquan
authors.initials: Q
authors.lastname: Sun
authors.forename: Xiao
authors.initials: X
authors.lastname: Zhang
authors.forename: Rong
authors.initials: R
authors.lastname: Zheng
authors.forename: Kaijun
authors.initials: K
authors.lastname: Yang
authors.forename: Yawei
authors.initials: Y
authors.lastname: Yuan
authors.forename: Quan
authors.initials: Q
authors.lastname: Yuan
keywords: House Ear Institute-Organ of Corti-1; radiation induced ototoxicity; tanshinone IIA