牛磺酸对锰致大鼠前额皮质神经毒性损害的干预研究

目的 探讨牛磺酸对锰致大鼠前额皮质神经毒性损害的干预作用.方法 取SD雄性大鼠104只,分为4组:(1)空白对照组:腹腔注射等容量生理盐水.(2)染锰组:每天腹腔注射氯化锰溶液15 ms/ks,连续3个月.(3)牛磺酸预防性干预组:染锰剂量和方法与染锰组一致;腹腔注射牛磺酸溶液200 mg/kg,与染锰同时进行,每周3次,连续3个月.(4)牛磺酸治疗性干预组:染锰剂量和方法与染锰组一致;在连续染锰3个月后停止染锰,再给予腹腔注射牛磺酸,每周3次,连续注射3个月.观察大鼠前额皮质神经元的细胞凋亡并检测丙二醛(MDA)含量和超氧化物歧化酶(SOD)活力.结果 (1)锰对大鼠前额皮质的神经元有诱导凋亡的作用,染锰组凋亡率(20.2±4.3)%]明显高于对照组(1.8±2.1)%],差异有统计学意义(P<0.05).牛磺酸预防性干预和治疗性干预后,细胞凋亡率下降,与染锰组相比,差异有统计学意义(P<0.05).(2)染锰组MDA含量较对照组升高,SOD活力较对照组降低,差异均有统计学意义(P<0.05).与染锰组相比,牛磺酸预防性干预组SOD活力增加,MDA含量降低,差异有统计学意义(P<0.05).结论 在体内锰通过氧化应激诱导神经细胞凋亡;牛磺酸抑制锰对神经元凋亡的诱导,通过抗氧化而发挥抗锰神经毒性的作用.

Intervenient effect of taurine on neurotoxicity of manganese in rat's prefrontal cortex

Objective To investigate the mechanisms of taurine(Tau) preventive effect on neurotoxicity induced by manganese (Mn) in rat's prefrontal cortex. Methods SD rats were divided into four groups after one week of observation: normal control:the group animals received daily intraperitoneal (ip.) injections of sterile saline for 3 months; Mn treated group (Mn): rats received ip. injection of MnCl2·4H2O once a day for 3 months;Tau preventive group (Mn+Tau):The Mn level of this group were the same as Mn's,the Tau level 200 mg/kg,three times per week, for 3 months;Tau treated group(Mn→Tau): After received the daily injection of Mn as Mn group for 3 months,the rats received Tau three times per week for 3 months. The dose of Mn and Tau were the same as above. The experiment lasted 6 months. Results (1)Mn induced apoptosis of neurons in rat's prefrontal cortex. The ratio of apoptosis of neurons in the Mn treated group (20.0±4.3)%] was higher than that of the control group (1.8±2.1)%](P<0.05) and the ratio of apoptosis in Tau preventive group (Mn+Tau) was lower than that of the Mn treated group (P<0.05). (2)The production of MDA in Mn treated group was higher than the control group (P<0.05) and the activity of SOD was lower than that in the control group. In Tau preventive group(Mn+Tau), Tau increased the activity of SOD and decreased the production of the MDA, with the significant difference level compared to the Mn treated group(P<0.05). Conclusion Mn induces apoptosis in rat's prefrontal cortex neurons. The main mechanisms of Tau preventing eytoxicity against Mn is the reduction of the oxidative stress in prefrontal cortex neurons.