Objective To observe the effect of acupuncture of “Yinlingquan”(SP9) and “Sanyinjiao”(SP6) on expression of phosphatidylinositol-3 kinase/protein kinase B/mammalian target protein of rapamycin(PI3 K/Akt/mTOR) signaling in adjuvant arthritis(AA) rats

so as to explore its mechanism underlying improvement of AA. Methods Forty-eight male Wistar rats were randomly divided into normal control

AA model

acupuncture and medication(tripterygium wilfordii) groups

with 12 rats in each group. The AA model was established by putting the rats in a windy

cold and wet environment for 12 h

once every day for 21 days and injection of Freund's complete adjuvant(CFA) into the sole of the right hindlimb on the 21

(st)

day. Manual acupuncture stimulation was applied at SP9 and SP6 for 30 min/time

once a day for 21 days. Rats of the medication group received gavage of tripterygium wilfordii tablets solution(8 mg/kg)

once a day for 21 days

and those of the normal control group and model group received gavage of the same amount of normal saline

once a day for 21 days. The degree of joint swelling and arthritis index(AI) were detected 1 day before modeling

3 days after modeling

and 21 days after the treatment. Twenty-four hours after the last treatment

the contents of serum cytokines interleukin(IL)-17

IL-6 and tumor necrosis factor(TNF)-α were detected by enzyme-linked immunosorbent assay(ELISA); and changes of synovial ultrastructure were observed under electron microscope. Western blot was used to detect the expression levels of PI3 K

Akt

phosphorylated protein kinase B(p-Akt)

phosphorylated mammalian rapamycin target protein(p-mTOR)

mTOR

microtubule associated protein 1 light chain 3 B(LC3-Ⅱ) and mammalian atg6 homologous protein(Beclin-1) in the synovial membrane tissue. Results Compared with the normal control group

the joint swel-ling degree and AI

contents of serum TNF-α

IL-6 and IL-17

and the expression levels of PI3 K

Akt

p-Akt

mTOR and p-mTOR in the synovium were increased in the model group(P

<

0.05)

while the expression levels of LC3-Ⅱ and Beclin-1 proteins in the synovium were significantly decreased(P

<

0.05). Compared with the model group

the joint swelling degree and AI

contents of serum TNF-α

IL-6 and IL-17

and the expression levels of PI3 K

Akt

p-Akt

mTOR and p-mTOR were significantly decreased in the acupuncture and medication groups(P

<

0.05)

while the expresion levels of LC3-Ⅱ and Beclin-1 proteins were significantly increased(P

<

0.05). Comparison between the two treatment groups showed that the therapeutic effects of acupuncture were obviously weaker than those of medication in down-regulating TNF-α and IL-6

Akt

p-Akt and mTOR levels(P

<

0.05) and in up-regulating Beclin-1 expression(P

<

0.05). Outcomes of electron microscope displayed widened nuclear membrane space

some fractured mitochondrial cristae with vacuoles

expanded rough endoplasmic reticulum

reduction of autophagosomes in the cytoplasm and ruptured synovial cell membrane in the model group

and increase of autophagosomes

deformed organelles in the acupuncture and medication groups.Conclusion Acupuncture can relieve the inflammatory reactions and joint synovial injury of the affected joint in AA rats which may be associated with its effects in inhibiting PI3 K/Akt/mTOR signaling and increasing the auto-phagy level of synovial cells.