锰对大鼠脑片的损伤及对细胞α-突触核蛋白表达的影响

Injury on neurocyte by manganese and its effect on alpha-synuclein expression in brain slices

目的研究锰对脑多巴胺神经细胞的毒性作用,重点观察α-突触核蛋白与细胞凋亡的改变。方法利用体外脑片培养模型,用不同浓度氯化锰(0,25,100,400μmol/L)处理脑片24 h后,观察脑片中酪氨酸羟化酶(tyrosine hydroxylase,TH)阳性细胞改变,培养液中乳酸脱氢酶(lactate dehydrogenase,LDH)的释放量,细胞凋亡率以及α-突触核蛋白的表达。结果随着Mn处理浓度的增加,脑片神经细胞损伤逐渐加重。与对照组比较,锰处理脑片导致TH阳性细胞数明显减少,LDH释放量、细胞凋亡率以及α-突触核蛋白的表达均明显增加。结论锰对多巴胺神经细胞有毒性作用,并且锰可以通过诱导α-突触核蛋白过表达而造成神经细胞损伤。

Objective The aim Of this study is to explore the toxic effects of manganese（Mn） on brain dopamine nerve ceils on brain slices,especially focus on the change of Mn-induced protein expression of alpha-synuclein and apoptosis. Methods Using cultured brain slice model in vitro,treated with different concentrations of Mn（0,25,100,400 μmol/L）for 24 h,detect the change of TH-positive cells, lactate dehydrogenase （LDH）release amount in culture medium;apoptosis rate and the protein expres- sion pattern of alpha-synuclein. Results With the increase of Mn concentration, nerve cell damage gradually aggravated in brain slice ; compared with control group, TH positive cells obviously reduced in Mn-treated brain slices, while the LDH release amount, apoptosis rate and alpha-synuclein expression level were all significantly increased. Conclusion The results suggested that Mn had toxic effect on dopaminergic neurons, which could damage neurocytes through inducing over-expression of alpha-synuclein.