鸢尾素对新生大鼠高胆红素血症细胞凋亡的影响

摘要目的：探究鸢尾素对新生大鼠高胆红素血症细胞凋亡的影响。方法：将96只新生SD大鼠随机分为对照组（N组）和模型组（M组）,于7和10日龄腹腔注射胆红素溶液进行造模。造模成功后将M组随机分为T0组、T1组、T2组、T3组。T1、T2、T3组分别侧脑室注射40、60和80 μg/kg的鸢尾素溶液,余各组注射等量磷酸盐缓冲液溶液。侧脑室注射24h后,神经行为学、苏木精-伊红染色（Hematoxylin-Eosin staining,HE）、原位末端标记法（terminal-deoxynucleoitidyl transferase mediated nick end labeling,Tunel）检测海马区病理改变并统计凋亡率,Western Blot检测海马Bcl-2、Bax和Caspase-3蛋白相对表达量。结果：侧脑室注射鸢尾素后。平面翻正反射：T3组所需时间少于T0、T1、T2组且多于N组（P<0.01）;负趋地性反射：T3组所需时间少于T0、T1、T2组（P<0.01,P<0.05）。HE染色：M组海马神经细胞核固缩、裂解,排列紊乱。T1、T2、T3组细胞形态等不同程度改善。Tunel染色：M组Tunel+细胞增多,布满视野;N组Tunel+细胞少,呈零星分布;T3组凋亡率低于T0、T1组（P<0.05）。Western Blot：各组Bcl-2蛋白相对表达量无显著性意义（P>0.05）;T0组Bax蛋白高于其余各组（P<0.05）,T3组低于T1组（P<0.05）;T0组Bcl-2/Bax值低于N、T3组（P<0.05）,T1、T2组均低于T3组（P<0.05）;T0组Caspase-3蛋白高于其余各组（P<0.05）,N组低于T1组（P<0.05）,T1组高于T3组（P<0.05）。结论：鸢尾素可能通过减少Bax、Caspase-3蛋白表达,升高Bcl-2/Bax值来减轻神经细胞凋亡且与鸢尾素注射剂量相关。

Effects of irisin on apoptosis in neonatal rats with hyperbilirubinemia

AbstractObjective： To investigate the effect of irisin on apoptosis of hyperbilirubinemia cells in neonatal rats.Method： Ninety-six newborn SD rats were randomly divided into the control group（N group） and the model group（M group）. The model was established by intraperitoneal injection of bilirubin solution at age 7 and 10 days. After successful modeling, the M group was randomly divided into four groups: T0, T1, T2, T3. Groups T1, T2, and T3 received intracerebroventricular injections of 40, 60, and 80 μg/kg irisin solution, respectively, while the other groups were injected with an equivalent volume of phosphate buffer saline （PBS） solution. After 24 hours, neurobehavioral assessments were conducted, hematoxylin-eosin （HE） staining, terminal - deoxynucleoitidyl transferase mediated Nick end labeling （Tunel） were used to detect the hippocampus pathological changes and apoptosis rate statistics, and Western Blot was used to detect relative expression levels of Bcl-2, Bax and Caspase-3 proteins in hippocampus.Result： After irisin injection, the T3 group required less time needed for planar double positive reflection than the T0, T1, T2 and more than N group （P<0.01）; negative geotaxis reflex time was also less in T3 group compared to T0, T1, T2 groups（P<0.01, P<0.05）. HE staining showed nuclear pyknosis, cleavage, and disordered arrangement of hippocampal neurons in the M group. The cell morphology was improved to varying degrees in T1, T2 and T3 groups. Tunel staining showed increased Tunel+ cells throughout the field in M group, sparse distribution in N group and lower apoptosis rates in T3 group compared to T0 and T1 groups （P<0.05）. Western Blot showed no significant difference in the relative expression of Bcl-2 protein among all groups（P>0.05）; T0 group had higher Bax protein levels compared to the rest of groups （P<0.05）, and lower in T3 group compared to T1 group （P<0.05）; The Bcl-2/Bax ratio was lower in T0 group compared to N and T3 group（P<0.05）, and lower in T1, T2 groups compared to T3 group （P<0.05）; The expression of Caspase-3 protein were higher in T0 group than that in other groups （P<0.05）,lower in N group than T1 group（P<0.05）,and higher in T1 group than T3 group （P<0.05）.Conclusion： Irisin may reduce the apoptosis of nerve cells by reducing the expression of Bax and Caspase-3 protein and increasing the Bcl-2/Bax ratio, with effects dependent on the injection dose of irisin.