Effect of electroacupuncture at different frequencies on brain insulin signaling transduction pathway in Alzheimer's disease mice / 中国针灸

OBJECTIVE@#To observe the effect of electroacupuncture (EA) at different frequencies on learning and memory functions, as well as the relevant proteins of brain insulin signal transduction pathway in Alzheimer's disease (AD) mice and explore the effect mechanism of EA in treatment of AD.@*METHODS@#Seventy-two SPF Kunming male mice were randomized into a blank group, a sham-operation group, a model group, a 2 Hz EA group, a 15 Hz EA group and a 30 Hz EA group, 12 mice in each one. In the model group and each EA group, AD model were established by the injection with streptozotocin (ST2) solution (8 mg/kg) into the left lateral ventricles. In the sham-operation group, 0.9% sodium chloride solution of the same volume was injected into the left lateral ventricles. After successful modeling, in each EA group, EA was applied at "Baihui" (GV 20), "Dazhui" (GV 14) and "Shenshu" (BL 23) with corresponding frequencies, once daily. One course of EA intervention consisted of 7 treatments and 2 courses were given totally at interval of 1 day. After modeling and intervention, Morris water maze test was conducted for the mice of each group. Using immunohistochemistry and Western blot method, the protein expression of insulin receptor (IR), insulin receptor substrate-1 (IRS-1) and phosphatidylinositol 3-kinase (PI3K) was detected in the hippocampal of the mice after intervention.@*RESULTS@#Compared with the blank group, in the model group, the 2 Hz, 15 Hz and 30 Hz EA groups, the escape latency and the first time of crossing the platform were all extended (P<0.01), and the number of crossing the platform was reduced (P<0.01) after modeling. When compared with the blank group, the escape latency and the first time of crossing the platform were all extended (P<0.01), and the number of crossing the platform was reduced (P<0.01) in the model group after intervention. In the 2 Hz, 15 Hz and 30 Hz EA groups, the escape latency and the first time of crossing the platform were all shortened (P<0.01), and the number of crossing the platform was increased (P<0.05, P<0.01) after intervention when compared with the model group. The escape latency and the first time of crossing the platform were all shortened (P<0.01, P<0.05), and the number of crossing the platform was increased (P<0.05) in the 15 Hz and 30 Hz EA groups in comparison with the 2 Hz EA group. The protein expression levels of IR, IRS-1 and PI3K were reduced in the model group when compared with those of the blank group (P<0.01, P<0.05); and these protein expression levels were increased in the 15 Hz and 30 Hz EA groups compared with the model group (P<0.05, P<0.01). Compared with the 2 Hz EA group, the protein expression levels of IR, IRS-1 and PI3K were all elevated in the 15 Hz and 30 Hz EA groups (P<0.05).@*CONCLUSION@#The learning and memory function of AD mice may be improved through regulating brain insulin signaling transconduction pathway with electroacupuncture, and electroacupuncture at 15 Hz and 30 Hz obtains the overall better effect compared with the intervention at 2 Hz.

The mitochondrial toxicity of bentysrepinine on HepG2 cells / 中国药理学通报

Aim To provide references for clinical trials dose and rational drug use by evaluating mitochondrial toxicity of bentysrepinine on HepG2 cells.Methods Mitochondrial toxicity of bentysrepinine on HepG2 cells was cmomprehensively evaluated by measuring proliferation inhibition rate, lactic acid content in culture supernatant, reactive oxygen species(ROS) content, mitochondrial membrane potential (MMP) variation and the activity of mitochondrial respiratory chain complex enzymes Ⅰ to Ⅳ.Results The half inhibitory concentration of bentysrepinine of HepG2 cells was 359 μmol·L-1.Compared with the control group, bentysrepinine could reduce the MMP, raise the level of lactic acid, increase the content of ROS and lower the activity of mitochondrial respiratory chain complex enzymes Ⅰ to Ⅲ with the concentration of 400 μmol·L-1(196 mg·L-1), showing an obvious mitochondrial toxicity.Compared with lamivudine and adefovir dipivoxil, bentysrepinine exerted no influence on indexes above with the same concentration 100 μmol·L-1.Conclusions Bentysrepinine shows an obvious mitochondrial toxicity on HepG2 cells with the concentration of 400 μmol·L-1.This mitochondrial toxicity is not presented with the concentration of 200 μmol·L-1.It shows that the safety range of bentysrepinine about mitochondrial toxicity is relatively wide.The test plays a guiding role in clinical trial dose design as well as clinical treatment.