首页  期刊介绍 征稿简则 编委会 期刊征订 广告服务 留言板 联系我们 English

中国应用生理学杂志 ›› 2020, Vol. 36 ›› Issue (6): 529-533.doi: 10.12047/j.cjap.6007.2020.112

• 研究论文 •    下一篇

雌激素对老年C57BL/6J小鼠耳蜗螺旋神经节细胞凋亡的影响*

陈龙1,4, 杨玉琪1, 冯子奕1, 李雪蕊1, 韩子伟2, 马克涛1, 司军强1, 李丽3△   

  1. 1.石河子大学医学院生理教研室, 新疆 石河子 832002;
    2.新疆军区总医院第951医院, 新疆 库尔勒 841000;
    3.嘉兴学院医学院, 浙江 嘉兴 314000;
    4.中国人民解放军69340部队, 新疆 阿勒泰 836100
  • 收稿日期:2020-01-19 修回日期:2020-11-16 出版日期:2020-11-28 发布日期:2021-03-15
  • 通讯作者: Tel: 13899517588; E-mail: Lily7588@163.com
  • 基金资助:
    *国家自然科学基金资助(81960188, 81560175)

Effects of estrogen on apoptosis of spiral ganglion cells in cochlea of aged C57BL/6J mice

CHEN Long1,4, YANG Yu-qi1, FENG Zi-yi1, LI Xue-rui1, HAN Zi-wei2, MA Ke-tao1, SI Jun-qiang1, LI Li3△   

  1. 1. Department of Physiology, Shihezi University College Xinjiang, Shihezi 832002;
    2. No. 951 General Hospital of Xinjiang Military Region, Kuerle 841000;
    3. Jiaxing Medical College, Jiaxing 314000;
    4. Unit 69344 of the People's Liberation Army, Aletai 836100, China
  • Received:2020-01-19 Revised:2020-11-16 Online:2020-11-28 Published:2021-03-15

摘要: 目的:观察雌激素对于老年C57BL/6J小鼠耳蜗螺旋神经节细胞凋亡的影响,并探讨雌激素对老年性耳聋保护作用的可能机制。方法:将40只C57BL/6J雌鼠分为以下4组(10只/组): 3 m组(3月龄组),12 m组(12月假手术组); 12 m OVX组(12月去卵巢组),在9月龄行双侧卵巢切除术,正常饲养至12月龄;12 m OVX+E2组(雌激素干预组)在9月龄行双侧卵巢切除术,经过1月洗脱期后,给予皮下注射雌激素100 μg/(kg·d),持续2月至12月龄,其余各组小鼠正常喂养。至12 m OVX+E2组小鼠给药结束后,尾静脉采血,酶联免疫吸附( ELISA) 法检测各组小鼠血清雌激素水平;听性脑干反应(ABR)检测各组小鼠听力阈值变化;用2%戊巴比妥钠麻醉小鼠,断颈后取双侧耳蜗,石蜡包埋切片,苏木精-伊红HE染色观察各组小鼠耳蜗螺旋神经节形态学变化;TUNEL 染色观察各组小鼠耳蜗螺旋神经节神经元凋亡情况;取耳蜗螺旋神经节,应用实时荧光定量PCR(QRT-PCR)检测各组小鼠耳蜗螺旋神经节凋亡蛋白Caspase-3、Bax、Bcl-2 mRNA 表达水平。结果:12 m组与3 m组相比,小鼠听力阈值升高(P<0.01),耳蜗螺旋神经节细胞出现缺失严重及异常凋亡(P<0.01);12 m OVX组小鼠听力阈值高于12 m组(P<0.01),且螺旋神经节细胞缺失加重,细胞凋亡增多(P<0.01),凋亡蛋白 Caspase-3、Bax mRNA水平升高(P< 0.01),抗凋亡蛋白Bcl-2 mRNA水平降低(P<0.01);外源性给予雌激素12 m OVX+E2组,较12 m OVX组,听力阈值降低(P<0.01),细胞凋亡减少,凋亡蛋白 Caspase-3、Bax mRNA水平降低(P<0.01),抗凋亡蛋白Bcl-2 mRNA水平升高(P<0.01)。结论:雌激素可抑制老年C57BL/6J小鼠耳蜗螺旋神经节细胞凋亡,从而实现对老年性耳聋的保护作用。

关键词: 老年性耳聋, 小鼠, 耳蜗螺旋神经节, 雌激素, 凋亡

Abstract: Objective: To observe the effects of estrogen on cochlear spiral ganglia cell apoptosis in aged C57BL/6J mice, and to explore the possible mechanism of estrogen's protective effects on senile deafness. Methods: Forty C57BL/6J mice were divided into the following four groups (10 mice/group): 3 m group (3 months old group), 12 m group (12 months old sham operation group); In the 12 m OVX group (ovariectomized at 12 months), bilateral oophorectomy was performed at the age of 9 months and normal feeding was performed until the age of 12 months.The 12m OVX+E2 group (estrogen intervention group) underwent bilateral oophorectomy at 9 months of age. After the one-month washout period, mice in the other groups were treated with estrogen at the dose of 100 μg/(kg·d) by subcutaneous injection, lasting 2 months to 12 months old. Mice in the other groups were fed normally.Blood samples were collected from the tail vein at the end of the treatment in 12 m OVX+E2 group. Enzyme-linked immunosorbent assays (ELISAs) was used to determine the serum estrogen levels. Auditory brainstem response (ABR) was used to detect the changes of hearing threshold in each group.Mice were anesthetized with 2% pentobarbital sodium. Bilateral cochlea was extracted after neck amputation and paraffin-embedded sections were performed.Hematoxylin eosin (HE) staining was used to observe the morphological changes in the cochlea spiral ganglion neurons (SGN), and TUNEL staining was used to observe the apoptosis of SGN. The expression levels of Caspase-3, Bax and Bcl-2 mRNA of the apoptotic proteins in cochlear spiral ganglion were measured by real-time fluorescence quantitative PCR (QRT-PCR). Results: Compared with the 3 m group, the hearing threshold of the 12 m group was improved, the loss of spiral ganglion cells was aggravated, and the apoptosis of the cells was increased(P<0.01). After removal of the ovaries, the hearing threshold of the mice in the 12 m OVX group was higher than that in the 12 m control group (P<0.01), and this increased threshold was accompanied by an increased loss of spiral ganglion cells, and increased apoptosis (P<0.01). Meanwhile, the mRNA levels of apoptotic protein Caspase-3 and Bax were increased (P<0.01), while the mRNA level of anti-apoptotic protein Bcl-2 was decreased (P<0.01). After exogenous estrogen was given to the 12 m OVX+E2 group, the hearing threshold was lower than that in 12 m OVX group(P<0.01). At the same time, the apoptosis of helical ganglion cells was reduced, the mRNA levels of Caspase-3 and Bax were decreased (P<0.01), and the Bcl-2 mRNA level was increased (P<0.01). Conclusion: Estrogen inhibited apoptosis of cochlear spiral ganglion cells in aged C57BL/6J mice ,thus achieving a protective effect on presbycusis.

Key words: presbycusis, mice, Cochlea spiral ganglion, oestrogen, apoptosis

中图分类号: 

版权所有 © 2015 《中国应用生理学杂志》编辑部
京ICP备16058274号-1
地址:天津市和平区大理道1号,邮编:300050  电话:022-84655184  E-mail:tjzgyish@163.com
本系统由北京玛格泰克科技发展有限公司设计开发 技术支持:support@magtech.com.cn