Effects of tibolone on apoptosis of neurons after cerebral ischemia-reperfusion injury in rats / 第二军医大学学报

ABSTRACT

Objective: To study whether the neuroprotective effect of tibolone during cerebral ischemia injury is associated with its anti-apoptosis effect. Methods: A total of 30 healthy adult female Sprague Dawley rats were evenly randomized into sham-operated group, ovariectomized group, and tibolone group(0.25 mg/[kg·d]). Brain ischemia model was induced by left middle cerebral artery occlusion(MCAO) for 2 hours followed by 24 hours reperfusion. All animals were killed and the cerebral infarction volumes were determined by 2,3,5-triphenyltetrazlium chloride (TTC) staining and image analysis. Apoptotic cells were labeled by Terminal deoxynucleotidyl Transferase-mediated dUTP nick end labeling (TUNEL). The expression of Bcl-2, Bax, and caspase-3 was analyzed by immunohistochemical SP method. Results: Compared with the sham-operated group(P<0.05), cerebral infarction volume was significantly reduced, TUNEL positive cells was significantly decreased(P<0.01), Bcl-2 positive cells were significantly increased, and Bax(P<0.01), caspase-3 postive cells were significantly reduced compared with tibolone treated groups (P<0.01). Conclusion: Tibolone can inhibit the neuron apoptosis following cerebral ischemia injury in OVX rats, displaying a neuroprotective effect.