Tongxinluo capsule inhibits oxidative stress in diabetic peripheral neuropathy mice by inhibiting the activity of p-p38 MAPK / 中国药理学通报

ABSTRACT

Aim To investigate the effects of Tongxin-luo capsule on oxidative stress in diabetic peripheral neuropathy (DPN )mice and its mechanisms.Meth-ods KK/Upj-Ay mice were divided into model, Tongxinluo low-dose group, Tongxinluo middle-dose group and Tongxinluo high-dose group.C57BL/6 mice were selected as control group.Mice were given drugs intragastrically for 12 weeks.Paw withdrawal latency, motor nerve conduction velocity (MNCV)were detec-ted.Activity of superoxide dismutase (SOD),gluta-thione peroxidase (GSH-Px)and content of malondial-dehyde (MDA)in blood were detected by colorimetric method.The expression of heme oxygenase-1 (HO-1 ),γ-glutamyl cysteine synthetase (γ-GCS ) of sciatic nerve was examined by real time PCR and Western blot.The protein expression of p38 MAPK,p-p38 MAPK,JNK,p-JNK,ERK,p-ERK was examined by Western blot.Results Compared with model group, paw withdrawal latency was increased and MNCV was faster in Tongxinluo group (P <0.05 ,P <0.0 1 ). SOD and GSH-Px contents significantly increased, MDA content decreased (P <0.01 ).HO-1,γ-GCS mRNA and protein expression significantly increased (P<0.05,P <0.01 )in Tongxinluo group.p-p38 MAPK protein expression decreased in Tongxinluo group (P<0.05 ).Conclusion Tongxinluo can in-hibit oxidative stress in DPN of mice via suppressing the phosphorylation of p38 MAPK.