Objective

2

To observe the effects of ultrasound-guided foraminal electroacupuncture on neuronal apoptosis and motor function in rats with spinal cord injury (SCI)

and to explore the potential underlying mechanisms.

Methods

2

Thirty-six SPF-grade Sprague-Dawley rats were randomly assigned to a sham operation group

a model group

and an ultrasound-guilded electroacupuncture group (electroacupuncture group)

with 12 rats in each group. In the sham operation group

the spinal cord was exposed and then t

he incision was sutured without contusion. In the other two groups

SCI models were established using a modified Allen’s impact method. On days 1

3

7

and 14 after modeling

the electroacupuncture group received electroacupuncture intervention at the T

9

/T

10

and T

10

/T

11

intervertebral foramen under ultrasound guidance

avoiding spinal cord injury. Stimulation parameters were dense-disperse wave at 2 Hz/100 Hz and 1-2 mA for each session. Following interventions on days 1

3

7

and 14

the Basso-Beattie-Bresnahan (BBB) score was assessed; the inclined plane test was used to assess hindlimb grip strength in rats. After the intervention

HE staining was used to observe spinal cord morphology; TUNEL staining was used to detect neuronal apoptosis; ELISA was used to measure the serum levels of interleukin (IL)-6

IL-1β

and tumor necrosis factor-alpha (TNF-α); Western blot was used to analyze the protein expression of Wnt-4

β-catenin

c-Myc

Bax

Bcl-2

and NeuN in spinal tissue; quantitative real-time PCR was used to detect the mRNA expression of Wnt-4

β-catenin

c-Myc

Bax

Bcl-2

and NeuN.

Results

2

Compared with the sham operation group

the model group showed significantly reduced BBB scores (

P

<

0.05)

and reduced inclined plane angles (

P

<

0.05) at all time points. Compared with the model group

the electroacupuncture group exhibited increased BBB scores on days 3

7

and 14 (

P

<

0.05)

and higher inclined plane angles on days 1

3

7

and 14 (

P

<

0.05). Compared with the sham operation group

the model group showed disorganized spinal cord structure with increased inflammatory cells and necrotic neurons

higher number of apoptotic neurons in spinal tissue (

P

<

0.05)

elevated serum IL-6

IL-1β

and TNF-α levels (

P

<

0.05)

increased protein and mRNA expression of Wnt-4

β-catenin

c-Myc

and Bax (

P

<

0.05)

and

decreased protein and mRNA expression of Bcl-2 and NeuN in spinal tissue (

P

<

0.05). Compared with the model group

the electroacupuncture group had fewer inflammatory cells and apoptotic neurons in spinal tissue (

P

<

0.05)

reduced serum IL-6

IL-1β

and TNF-α levels (

P

<

0.05)

increased protein and mRNA expression of Wnt-4

β-catenin

Bcl-2

and NeuN (

P

<

0.05)

and decreased protein and mRNA expression of c-Myc and Bax in spinal tissue (

P

<

0.05).

Conclusion

2

Ultrasound-guided foraminal electroacupuncture could improve motor function in rats with SCI

potentially by regulating the expression of molecules related to the Wnt-4/β-catenin signaling pathway to inhibit neuronal apoptosis and inflammatory responses.