Objective

2

To investigate the effect of electroacupuncture (EA) on neurological function in rats with cerebral ischemia-reperfusion injury (CIRI) by regulating adenosine monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR)/Unc-51-like kinase 1 (ULK1) signaling pathway.

Methods

2

Thirty-three male SD rats were randomly divided into a sham-operation group

a model group and an EA group

with 11 rats in each group. The right middle cerebral artery occlusion/reperfusion (MCAO/R) model was prepared by thread occlusion method in the model group and the EA group. In the sham-operation group

no thread was inserted after vascular separation. After the successof modeling

in the EA group

EA was applied to ＂Baihui＂ (GV 20) and ＂Zusanli＂ (ST 36) on the affected side

with disperse-dense wave

the frequency of 2 Hz/15 Hz

for 20 min

once a day. EA was delivered continuously for 3 days. On day 1 and day 3 of operation

the score of the modified neurological deficit scale (mNSS) was evaluated. After intervention completion

the cerebral infarction area was measured by the thiazolyl blue tetrazolium chloride (TTC) method. Nissl staining was used to observe the damage of cortical neurons on the ischemic side in each group. Using transmission electron microscopy

the ultrastructure of cortical neurons on the ischemic side was observed. With the immunofluorescence method adopted

the positive expression of the related protein 1 light chain 3 (LC3) and benzyl chloroform (Beclin-1) on the ischemic side was detected. The protein expression of p-AMPK

AMPK

p-mTOR

mTOR

pS757-ULK1

ULK1 and chelating ligand 1 (p62) in the ischemic cortex was detected using Western blot method.

Results

2

① Compared with the sham-operation group

in the model group

the mNSS score increased (

P

<

0.01)

the percentage of infarction area was increased (

P

<

0.01); the cortical neurons on the ischemic side were loosely distributed

with karyopyknosis and vacuolization

and the number of neurons was reduced (

P

<

0.01); the cells were swollen and ruptured

mitochondrial shrunk

electron density higher

and there were a large number of autophagic debris. The positive expression of LC3 and Beclin-1 was elevated (

P

<

0.01)

and p-mTOR/mTOR

pS757-ULK1/ULK1 and the protein expression of p62 dropped (

P

<

0.01) in the ischemic cortex. ② Compared with the model group

in the EA group

the mNSS score was reduced (

P

<

0.05). The percentage of cerebral infarction area was descreased (

P

<

0.01); and the neurons were regularly distributed

the number of neurons increased (

P

<

0.01)

the structure of mitochondria was clearer

the crest fracture alleviated

and the damage of neurons attenuated. The positive expression of LC3 and Beclin-1 was dropped (

P

<

0.01)

and p-AMPK/AMPK reduced (

P

<

0.05)

and p-mTOR/ mTOR

pS757-ULK1/ULK1 and the protein expression of p62 increased (

P

<

0.01) in the ischemic cortex.

Conclusion

2

EA at ＂Baihui＂ (GV 20) and ＂Zusanli＂ (ST 36) inhibits autophay

attenuates neurological deficit and cerebral pathological damage in CIRI rats to protect the nerves

which may be obtained by regulating AMPK/mTOR/ULK1 signaling pathway.