The Journal of Practical Medicine ›› 2022, Vol. 38 ›› Issue (3): 311-317.doi: 10.3969/j.issn.1006⁃5725.2022.03.010

• Basic Research • Previous Articles     Next Articles

The mechanism of Ginkgo biloba extract in alleviating oxidative stress damage to the cochlea of presbycu⁃sis rats by the Nrf2/HO ⁃ 1 signal pathway

WANG Qingling*，ZHANG Mengxian，ZHOU Yingdong，GUOXiangdong，KANG Haoran，WANG Qinglin.   

  1. First Clinical Medical College of He′nan University of Chinese Medi⁃cine，Zhengzhou 450046，China

  • Online:2022-02-10 Published:2022-02-10
  • Contact: GUO Xiangdong E⁃mail：guoxiangdong0618@126.com

Abstract:

Objective To observe the effect of Ginkgo biloba extract on nuclear factor erythroid relatedfactor 2（Nrf2）/heme oxygenase 1（HO⁃1）signaling pathway in the cochlea of presbycusis rats，and to explore themechanism of Ginkgo biloba extract in protection of presbycusis. Methods 45 SD rats were randomly divided in⁃to a control group，model group，Ginkgo biloba extract low⁃dose group，medium⁃dose group and high⁃dose group，9 for each group. Auditory function was detected by auditory brainstem response（ABR）. The serum contents ofmalondialdehyde（MDA）and total superoxide dismutase（T⁃SOD）were detected by ELISA. Ultrastructure of spiralganglion cells was observed under a transmission electron microscope. Changes in the structure and quantity of haircells in the Apical，Middle，or Basal turn were observed by immunofluorescence staining. Expression levels of Nrf2and HO⁃1 proteins in the cochlea were detected by immunohistochemistry and Western blotting. Results As com⁃pared with those in the control group，the ABR threshold in the model group was significantly increased，the serumcontent of MDA was increased，whereas that of T ⁃SOD was decreased；the ultrastructure of spiral ganglion cellswas obviously destroyed，the morphology of the inner and outer hair cells were disordered，the number of hair cellswas greatly reduced，and the expression levels of Nrf2 and HO ⁃1 proteins were down ⁃ regulated. After treatmentwith different doses of Ginkgo biloba extract，as compared with those in the model group，the ABR threshold wassignificantly reduced，the content of MDA was reduced，the content of T⁃SOD was increased，the ultrastructure ofspiral ganglia cells was significantly improved，the morphology of inner and outer hair cells were clear and the cellnumber gradually increased，and the expression levels of Nrf2 and HO ⁃1 proteins were up ⁃ regulated. Conclusions Ginkgo biloba extract can alleviate oxidative stress damage in the cochlea of presbycusis rats，and its mechanismmay be related to the regulation of Nrf2/HO⁃1 signaling pathway.

Key words:

presbycusis, ginkgo biloba extract, oxidative stress, mitochondrial dysfunction