[Effect of electroacupuncture on mitochondrial function in mice with Parkinson's disease]

To observe the effect of electroacupuncture (EA) on behavior, tyrosine hydroxylase (TH), mitochondrial complexes Ⅰ-Ⅳ, mitochondrial membrane potential and mitochondrial ultrastructure of Parkinson's disease (PD) mice, so as to explore its mechanism underlying improvement of PD.

C57BL/6 mice were randomly divided into normal, model, medication (Madopar) and EA groups (n=11 in each group). PD model was duplicated by intraperitoneal injection of 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP, 30 mg·kg^-1·d^-1) for consecutively 5 d. EA was performed on the chorea tremor areas on both sides of the head of mice for 15 min, once a day for 14 d. The behavioral changes of mice were observed. The expression of TH in substantia nigra compacta of midbrain was detected by immunohistochemistry. The activities of mitochondrial complexes Ⅰ-Ⅳ were measured. The changes of mitochondrial membrane potential were detected by JC-1 staining method. The ultrastructural changes of striatum mitochondria were observed by transmission electron microscope.

After modeling, the mice showed obvious behavioral abnormalities such as tremor, vertical hair and tail warping, and the pole test time in the model group was significantly longer than that in the normal group (P<0.01). After 7 and 14 days of the treatment, the pole test time in the EA and medication groups was shorter than that in the model group (P<0.05，P<0.01). Compared with the normal group, the number of TH positive cells of the substantia nigra, the mitochondrial membrane potential and the activity of mitochondrial complex I were decreased significantly in the model group (P<0.01), and EA and medication intervention reversed these changes (P<0.01). The mitochondrial structure of mice in the model group was obviously damaged, and the damage of mitochondrial structure was alleviated and the number of damaged mitochondria was decreased in the EA and medication groups.

EA can protect and promote the recovery of mitochondrial structure and function in MPTP-induced PD mice, which may play a neuroprotective effect on PD mice by improving mitochondrial dysfunction, balancing cell homeostasis and reducing dopaminergic neuron damage.