白皮杉醇对急性脑出血大鼠的保护作用及其机制

Effects and mechanisms of piceatannol on intracerebral hemorrhage in rats

目的研究白皮杉醇对急性脑出血大鼠脑组织保护作用,并探讨其作用机制。方法采用向脑组织注入自体动脉血建立急性脑出血大鼠模型,分别给予高剂量(Pic-H)、低剂量(Pic-L)白皮杉醇(200和100mg/kg),对各组大鼠进行神经功能缺损评分,酶联免疫吸附试验(ELISA)法检测血清中神经元特异性烯醇化酶(NSE)含量,原位末端标记法(TUNEL)染色检测脑细胞凋亡数,免疫印迹法(Western blot)检测脑组织中磷酸化c-Jun氨基末端激酶3(p-JNK3)、磷酸化c-Jun(p-c-Jun)和磷酸化转录激活因子2(p-ATF-2)蛋白表达。结果给予白皮杉醇后,与模型组相比,大鼠的神经功能缺损评分[Pic-L组(1.32±0.24)比(2.89±0.41),Pic-H组(0.98±0.21)比(2.89±0.41)]降低;大鼠血清中NSE的水平[Pic-L组(29.25±2.63)比(38.02±3.35)μg/L,Pic-H组(26.11±2.29)比(38.02±3.35)μg/L]降低;大鼠脑组织TUNEL阳性细胞百分比[Pic-L组(36.78±4.66)%比(62.34±6.24)%,Pic-H组(17.32±2.36)%比(62.34±6.24)%]减少;大鼠脑组织中p-JNK3蛋白表达[Pic-L组(2.67±0.21)比(4.97±0.34),Pic-H组(1.84±0.21)比(4.97±0.34)]降低;p-c-Jun蛋白表达[Pic-L组(2.17±0.19)比(3.38±0.31),Pic-H组(1.78±0.15)比(3.38±0.31)]降低;p-ATF-2蛋白表达[Pic-L组(1.79±0.13)比(2.99±0.27),Pic-H组(1.43±0.12)比(2.99±0.27)]降低;差异有统计学意义(均P<0.05)。结论白皮杉醇可能通过抑制JNK信号通路来减缓急性脑出血大鼠脑组织细胞的凋亡。

Objective To investigate the effect of piceatannol on intracerebral hemorrhage in rats and to explore the possible mechanisms. Methods Intracerebral hemorrhage model was established by injecting autologous blood into brain, and then rats were given piceatannol at dose of 100 or 200 mg/kg, respectively. The impairment of neural function was scored accordingly. Neuron specific enolization enzyme （NSE） level in serum was detected by enzymelinked immunosorbent assay （ELISA）. Cell apoptosis was determined by TUNEL staining. The protein expression of p-JNK, p-c-Jun and p-ATF-2 were analyzed by Western blot. Results After treatment with piceatannol, compared with the model group, the scores of neural function impairment （low dose group 1.32±0.24 vs 2. 89± 0.41, high dose group 0.98± 0.21 vs 2.89 ± 0.41）, the serum NSE levels [low dose group （29.25±2.63） vs （38. 02±3.35）μg/L, high dose group （26.11±2.29） vs （38.02±3.35）μg/L] and percentage of Tunel positive cells of brain tissue [low dose group （36.78±4.66）% vs （62.34± 6.24）%, high dose group （17.32 ±2.36）% vs （62.34±6.24） %] were decreased, so as the protein expression of p-JNK3 （low dose group 2.67±0.21 vs 4.97± 0.34, high dose group 1.84±0.21 vs 4.97±0.34）, p-c-Jun （low dose group 2.17±0.19 vs 3.38±0.31, high dose group 1.78±0.15 vs 3. 38±0.31） and p-ATF-2 （low dose group 1.79±0. 13 vs 2.99±0.27, high dose group 1.43± 0.12 vs 2.99 ± 0. 27 ）. All the differences were statistical significance （ all P 〈0. 05 ）. Conclusion Piceatannol protects against intracerebral hemorrhage in rats via inhibition of JNK signaling pathway.