ABSTRACT
Objective To examine the effect of estradiol (E2) treatment on ovariectomy (OVX) induced depressive-like behavior and possible mechanism by measuring inflammatory biomarkers levels oi interleukin-6 (IL-6) and tumor necrosis tactor-(x (TNF-ot) and brain-derived neurotrophic factor (BDNF) expression in amygdaia nucleus. Methods Thirty nine healthy aduit 缶male SD rats were randomly divided into three groups : sham operation group (SO), ovariectomized group (OVX) and ovariectomized estradiol treatment group (OVX + E2). After 6 weeks of E2 treatment, depressive like behavior was evaluated by opening field test (OFT) and sugar water preference test (SPT). The levels of inflammatory factors IL-6 and TNF-a in amygdala were measured by ELESA, and the expression of BDNF in rat amygdala was detected by immunohistochemical staining. Results The result of the SPT showed that OVX significantly decreased the sugar intake and sugar preference rate of rats, and E2 treatment significantly increased sugar water intake and sugar water preference rate of rats. The result of the OFT showed that OVX significantly decreased the numbers of crossing and rearing of rats, and reduced the time spent in the centre ; E2 treatment significantly increased the numbers of crossing and rearing of rats, and prolonged the time spent in the centre. ELESA and immunohistochemical analysis found the levels of IL-6 and TNF-a in amygdala increased significantly, while the average absorbance (AA) of BDNF in the amygdala reduced significantly (P<0.01 respectively) of rats in OVX group when compared with the SO group. And the levels of IL-6 and TNF-a in amygdala decreased significantly (P<0.01 respectively), while the A4 of BDNF increased significantly (P< 0.05) in the amygdala of rats in the OVX+EX group when compared with the OVX group. The difference was statistically significant. Conclusion E2 treatment improved depression-like behavior of OVX rats is partly due to increased antiinflammatory and activated the BDNF expression in amygdaloid nucleus, thus enhancing the neuroprotective effect of OVX rats.
ABSTRACT
Objective To observe the effects of 4-week low intensity treadmill exercise on the learning and memory, amino acid levels and the protein expression of protein kinase A ( PKA) , cyclic adenosine monophosphate response element binding protein( CREB) and brain-derived neurotrophic factor(BDNF) in the prefrontal cortex (PFC) of the vascular dementia (VD) rats. Methods Thirty-nine SD rats were randomly allocated to 3 groups, sham group (sham, n= 13) , vascular dementia group (VD, n= 13) and vascular dementia treaded with exercise group (VD + EX, n= 13). Chronic cerebral ischemia model in VD group and VD+EX group rats were established by permanent ligation of bilateral, then VD+EX group rats were submitted to 4-week low intensity treadmill exercise. After exercise, spatial learning and memory ability were evaluated by Moms water maze test ( MWM ) , glutamic ( Glu ) and gamma-aminobutyric acid (GABA) levels in the PFC were measured by high performance liquid chromatography( HPLC) ; the protein expression of PKA, CREB and BDNF in the PFC of rats were detected by Western blotting. Results The result of the MWM showed the average escape latency of rats in the VD group on the 1 -5 days was significantly higer than sham group, the time to first find the original platform was significantly prolonged and the platform crossings decreased significantly ( P 0. 05 ) between the two groups. Conclusion Four-week low-intensity running exercise improves the learning and memory ability of VD rats through enhancing the Glu level and activating PKA-CREB-BDNF signaling in the PFC of rats.