Abstract:

Abstract:Objective
To explore the effects of tanshinone ⅡA on the injury of dopaminergic neurons of Parkinson’s disease (PD) mouse model induced by 1-methy-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP),and to clarify the possible mechanism of its protective effects on dopaminergic neurons.Methods 60 C57BL/6N mice were randomly divided into control group,PD  model group and tanshinone ⅡA group(n=20).The mice in PD model group and tanshinone ⅡA group were treated with MPTP to establish PD models.The bebavior of the mice  in various groups was observed.The number of tyrosine hydroxylase (TH),cd11b,p47-phox,and inducibleni tricoxidesynthase (iNOS)-positive cells,and the protein expression levels of TH,cd11b,p47-phox and iNOS in the substantia nigra (SN) of the midbrain of the mice in various groups  were detected with immunohistochemistry,Western blotting and double-labeling immunofluorescence assay. Results Compared with control group,the mice  in PD model group exhibited typical symptoms of PD,and the number of TH-positive cells and the protein expression level of TH in the substantia nigra of the mice in PD model group were reduced by about 45% and 50%;the number of cd11b,p47-phox,iNOS-positive cells and the protein expression levels of cd11b,p47-phox,iNOS were markedly increased （P<0.01）.Compared with PD model group,the symptoms of PD of the mice in tanshinone ⅡA group were alleviated, the number of TH-positive cells and the expression level of TH protein in the SN were increased(P<0.01),and the number of cd11b,p47-phox and iNOS-positive cells and the TH protein expression levels were obviously decreased（P<0.01）.Conclusion Tanshinone ⅡA could mitigate the loss of dopaminergic neurons in the PD mouse model induced by MPTP.The mechanism of neuprotective effect may be related to the inhibition of microglial activation,NADPH oxidase and iNOS expressions.

Key words:  , Parkinson&rsquo, s disease, microglia, NADPH oxidase, inducible nitric oxide synthase, tyrosine hydroxylase, tanshinone ⅡA, mice