Park Joon-Ki, Hong Young-Pyo, Lee Sam-Jun
Division of Exercise and Health Science, College of Arts and Physical Education, Incheon National University, Incheon 22012, Republic of Korea.
Health Education Laboratory, Department of Physical Education, Korea National Sport University, Seoul 05541, Republic of Korea.
Mol Med Rep. 2017 Jul;16(1):435-440. doi: 10.3892/mmr.2017.6614. Epub 2017 May 19.
Ovariectomy (OVX) is a method used to block estrogen in female rats that induces hippocampal dysfunction and affects brain‑derived neurotrophic factor (BDNF) pathways. The majority of previous studies investigating OVX focused on BDNF expression in the hippocampus and cognitive function. The present study focused on the pathways of each BDNF type, precursor (proBDNF) and mature (mBDNF), and the effects of regular exercise in the hippocampus of ovariectomized rats. Female Sprague‑Dawely rats were used and OVX surgery was performed. After 1 week of recovery from surgery, two groups of rats that received OVX surgery were subjected to regular treadmill exercise for 8 weeks. The results of protein levels by western blotting indicated that the expression of proBDNF, p75 neurotrophin receptor (p75NTR) and c‑Jun N‑terminal protein kinase (JNK) was increased, and mBDNF, tropomyosin‑related kinase B (TrkB) and nuclear factor‑κB expression was significantly reduced in the OVX control group compared with the sham control group SC (P<0.05). Thus, the survival pathway by mBDNF was impaired and the pro‑apoptotic response was activated by increased JNK expression due to proBDNF‑p75NTR binding in the hippocampus of ovariectomized rats. By contrast, exercise reduced activation of the pro‑apoptotic response and increased mBDNF‑TrkB expression in the hippocampus of ovariectomized rats. Thus, regular exercise may increase the activation of survival pathways via mBDNF and reducing the activation of the pro‑apoptotic pathway of proBDNF in the hippocampus of ovariectomized rats.
卵巢切除术（OVX）是一种用于阻断雌性大鼠雌激素的方法，该方法会诱发海马功能障碍并影响脑源性神经营养因子（BDNF）通路。此前大多数研究OVX的实验都聚焦于海马体中BDNF的表达及认知功能。本研究聚焦于每种BDNF类型，即前体（proBDNF）和成熟体（mBDNF）的通路，以及规律运动对去卵巢大鼠海马体的影响。实验使用雌性斯普拉格-道利大鼠并进行了OVX手术。术后恢复1周后，两组接受OVX手术的大鼠进行了为期8周的规律跑步机运动。蛋白质印迹法检测蛋白质水平的结果表明，与假手术对照组（SC）相比，OVX对照组中proBDNF、p75神经营养因子受体（p75NTR）和c-Jun氨基末端蛋白激酶（JNK）的表达增加，而mBDNF、原肌球蛋白相关激酶B（TrkB）和核因子-κB的表达显著降低（P<0.05）。因此，mBDNF的存活通路受损，且去卵巢大鼠海马体中由于proBDNF-p75NTR结合导致JNK表达增加，从而激活了促凋亡反应。相比之下，运动减少了去卵巢大鼠海马体中促凋亡反应的激活，并增加了mBDNF-TrkB的表达。因此，规律运动可能会增加去卵巢大鼠海马体中通过mBDNF的存活通路的激活，并减少proBDNF促凋亡通路的激活。
