Effect of curcumin on the 11β-hydroxysteroid dehyarogenase 1 expression in spinal cords neuropathic pain rat model / 国际药学研究杂志

ABSTRACT

Objective To observe the effect of stress caused by neuropathic pain on serum cortisol concentration and expres-sion of 11β-hydroxysteroid dehyarogenase 1(11βHSD1)and investigate the action mechanism of curcumin for alleviating neuropathic pain. Methods The 72 male SD rats were randomly divided into 4 groups with 18 rats in each group:sham operation group(Sham), chronic constrictive injury group(CCI),solvent contrast group(SC)and curcumin treated group(Cur100). Curcumin(100 mg/kg/d) was given after the operation in Cur100 group. Paw thermal withdrawal(PTWL)and paw mechanical withdrawal threshold(PMWT)of rats were measured on 2 pre-operative and 1,3,5,7,10,and 14 post-operative days. The animals were deeply anesthetized,the blood was taken from the heart,and the L4-L5 dorsal root ganglion(DRG)of the operated side was removed. The change of cortisol was measured by ELISA and the change of 11βHSD1 expression in spinal cord and DRG was determined by immunochemistry and Western blot. Results Compared with sham group,PTWL and PMWT decreased significantly after operation in CCI group(P<0.01),serum cortisol concentration was significantly increased(P<0.01)and the expression of 11βHSD1 was significantly increased in CCI group(P<0.01). Compared with CCI group,the PMWT and PTWL was increased in CCI group(P<0.05),the serum cortisol concentration was decreased(P<0.05)and the expression of 11βHSD1 was inhibited in Cur100 group(P<0.05). Conclusion Stress caused by neuropathic pain triggered the release of cortisol to the blood and increased the expression of 11βHSD1 at the same time. Cur-cumin could alleviate thermal hyperalgesia and mechanical hyperalgesia induced by CCI and could also inhibit the serum cortisol con-centration and the expression of 11βHSD1 in spinal cord and DRG,which was likely to be related to pathogenesy and maintenance of neuropathic pain.