Effects of Yizhi Tiaoshen acupuncture on learning and memory function and the expression of phosphorylated tau protein in the hippocampus of Alzheimer's disease model rats / 中国针灸

OBJECTIVE@#To observe the effects of Yizhi Tiaoshen (benefiting mental health and regulating the spirit) acupuncture on learning and memory function, and the expression of phosphorylated tubulin-associated unit (tau) protein in the hippocampus of Alzheimer's disease (AD) model rats, and explore the effect mechanism of this therapy on AD.@*METHODS@#A blank group and a sham-operation group were randomly selected from 60 male SD rats, 10 rats in each one. AD models were established in the rest 40 rats by the intraperitoneal injection of D-galactose and okadaic acid in the CA1 region of the bilateral hippocampus. Thirty successfully-replicated model rats were randomly divided into a model group, a western medication group and an acupuncture group, 10 rats in each one. In the acupuncture group, acupuncture was applied to "Baihui" (GV 20), "Sishencong" (EX-HN 1), "Neiguan" (PC 6), "Shenmen" (HT 7), "Xuanzhong" (GB 39) and "Sanyinjiao" (SP 6); and the needles were retained for 10 min. Acupuncture was given once daily. One course of treatment was composed of 6 days, with the interval of 1 day; the completion of treatment included 4 courses. In the western medication group, donepezil hydrochloride solution (0.45 mg/kg) was administrated intragastrically, once daily; it took 7 days to accomplish one course of treatment and a completion of intervention was composed of 4 courses. Morris water maze (MWM) and novel object recognition test (NORT) were used to assess the learning and memory function of the rats. Using HE staining and Nissl staining, the morphological structure of the hippocampus was observed. With Western blot adopted, the protein expression of the tau, phosphorylated tau protein at Ser198 (p-tau Ser198), protein phosphatase 2A (PP2A) and glycogen synthase kinase-3β (GSK-3β) in the hippocampus was detected.@*RESULTS@#There were no statistical differences in all of the indexes between the sham-operation group and the blank group. Compared with the sham-operation group, in the model group, the MWM escape latency was prolonged (P<0.05), the crossing frequency and the quadrant stay time in original platform were shortened (P<0.05), and the NORT discrimination index (DI) was reduced (P<0.05); the hippocampal cell numbers were declined and the cells arranged irregularly, the hippocampal neuronal structure was abnormal and the numbers of Nissl bodies decreased; the protein expression of p-tau Ser198 and GSK-3βwas increased (P<0.05) and that of PP2A decreased (P<0.05). When compared with the model group, in the western medication group and the acupuncture group, the MWM escape latency was shortened (P<0.05), the crossing frequency and the quadrant stay time in original platform were increased (P<0.05), and DI got higher (P<0.05); the hippocampal cell numbers were elevated and the cells arranged regularly, the damage of hippocampal neuronal structure was attenuated and the numbers of Nissl bodies were increased; the protein expression of p-tau Ser198 and GSK-3β was reduced (P<0.05) and that of PP2A was increased (P<0.05). There were no statistically significant differences in the above indexes between the acupuncture group and the western medication group (P>0.05).@*CONCLUSION@#Acupuncture therapy of "benefiting mental health and regulating the spirit" could improve the learning and memory function and alleviate neuronal injure of AD model rats. The effect mechanism of this therapy may be related to the down-regulation of GSK-3β and the up-regulation of PP2A in the hippocampus, and then to inducing the inhibition of tau protein phosphorylation.

Changes in expression of Tau protein and phosphorylated Tau protein in neurons after spinal cord ischemia-reperfusion injury in rats / 中华创伤骨科杂志

Objective:To explore the changes in the expression of Tau protein and phosphorylated Tau (p-Tau) protein in neurons after spinal cord ischemia-reperfusion injury (SCII).Methods:Ninety-six healthy adult SD rats were randomly divided into a sham operation group ( n=48) and a SCII group ( n=48). Based on the reperfusion time of 3 h, 6 h, 12 h, 24 h, 48 h and 72 h, the SCII group was divided into 6 subgroups ( n=8 per subgroup). Immunohistochemical staining was used to observe the apoptosis of spinal cord neurons in the L 4-L 5 segments and the expression of Tau protein and p-Tau protein. Results:In the sham operation group, the neuron cells were intact, mainly concentrated in the gray matter. Tau protein was seen in a small number of neuron cells, and a small amount of filamentous p-Tau protein in the pernucleus and cytoplasm. There was no significant difference between Tau protein and p-Tau protein expression in neurons at each time point ( P>0.05). In the SCII group, scattered Tau protein was seen in the apoptotic cells while there was a strong positive expression of Tau protein in the non-apoptotic cells. The expression of Tau protein in the SCII group gradually increased after injury, reaching a peak at 48h and plateauing at 72 h, and was significantly different between any 2 time points (except for 72 h) ( P<0.05). In the SCII group, the positive expression of p-Tau protein was observed in the cytoplasm of the apoptotic cells in strips and sheets. It increased rapidly within 6 h but did not change significantly after 6 h, showing no significant difference between any 2 time points afterwards ( P>0.05). There was a statistically significant difference in the expression of Tau protein and p-Tau protein between the SCII group and the sham operation group at each time point ( P<0.05). Conclusion:It is hopeful to reduce the severity of spinal cord injury by regulating the expression of Tau protein and p-Tau protein within 6 to 48 hours after SCII.

Effect of early intervention of electroacupuncture on learning-memory ability and level of hippocampal phosphorylated Tau protein in SAMP8 mice / 中国针灸

OBJECTIVE@#To explore the effect of early intervention electroacupuncture (EA) at "Baihui" (GV 20), "Dazhui" (GV 14) and "Shenshu" (BL 23) on the learning-memory ability and the expression of phosphorylated Tau protein in the hippocampus of SAMP8 mice, so as to provide reference for the intervening period of EA for Alzheimer's disease (AD).@*METHODS@#A total of 36 3-month old SAMP8 mice were randomly divided into a model group, a 3-month-old EA group and a 9-month-old EA group, 12 mice in each group. Twelve normal SAMR1 mice with the same age were taken as the control group. The mice in the 3-month-old EA group and 9-month-old EA group were treated with EA at "Baihui" (GV 20), "Dazhui" (GV 14) and "Shenshu" (BL 23) separately 3 months old and 9 months old (continuous wave, 2 Hz, 1.5-2 mA), 20 min each time, once a day, 8 days as a course of treatment, with an interval of 2 days between courses, totally 3 courses of treatment were given. The mice sample in each group was collected at the age of 10 months after the learning-memory ability tested by Morris water maze. The expression of phosphorylated Tau protein in the hippocampus was detected by immunohistochemistry and Western blot, and the expression of Tau mRNA was detected by real-time PCR.@*RESULTS@#Compared with the control group, in the model group, the escape latency was significantly increased (<0.01), the time of stay in the original platform quadrant and the number of crossing the platform quadrant were reduced (<0.01), and the expressions of phosphorylated Tau protein and Tau mRNA in hippocampus were increased (<0.01). Compared with the model group, in the 3-month-old EA group and 9-month-old EA group, the escape latency was significantly reduced (<0.05), the time of stay in the original platform quadrant and the number of crossing the platform quadrant were increased (<0.05), and the expressions of phosphorylated Tau protein and Tau mRNA in hippocampus were reduced (<0.05). Compared with the 9-month-old EA group, in the 3-month-old EA group, the escape latency was significantly reduced (<0.05), the time of stay in the original platform quadrant and the number of crossing the platform quadrant were increased (<0.05), and the expressions of phosphorylated Tau protein and Tau mRNA were reduced (<0.01).@*CONCLUSION@#The early EA intervention could more effectively improve the learning-memory ability and inhibit phosphorylation of Tau protein in the hippocampus of SAMP8 mice.

The protective effect of rapamycin on beta-amyloid protein 25-35-induced PC12 cells death / 医学研究生学报

Objective Rapamycin can improve characteristic pathology of AD by improving the level of autophagy.But, its internal mechanism still needs further study.This study was aimed to observe the protective effect of Rapamycin (RAPA) on the injury of rat pheochromocytoma (PC12) cells induced by β-amyloid protein25-35 (Aβ25-35).Methods PC12 cells in the logarithmic phase were randomly divided into 5 groups: control group(similar free-serum DMEM), model group, 10μmol/L RAPA treated group, 40μmol/L RAPA treated group and 160μmol/L RAPA treated group(add 10μmol/L, 40μmol/L RAPA, 160μmol/L respectively).Except the control group, each group was cultured with 20μmol/L Aβ25-35 to established the cell injury model.Results ①Compared with the survival rate of cells[(51.47±2.59)%] and the apoptosis rate of cells[(52.22±2.33)%] of the model group,the survival rate of cells in 10、40、160μmol/L RAPA treated groups and control group[(54.64±2.42)%, (64.79±2.91)% ,(56.50±2.55)% and (99.98±0.73)%] significantly increased, but the apoptosis rate of cells [(45.33±2.83)%, (36.89±2.85)%, (48.00±2.83)% and (3.33±2.45)%] significantly decreased(All P<0.05).②In model group,the expressions of p-PKB is 0.33±0.01, p-mTOR is 1.97±0.05, p-tau is 2.09±0.19.Compared with model group, in 10、40、160μmol/L RAPA treated groups and control group,these expressions of p-PKB (0.37±0.01, 0.42±0.01, 0.40±0.01 and 0.44±0.02) were significantly increased, however p-mTOR (1.64±0.05, 0.66±0.04, 0.35±0.01 and 0.62±0.01) and p-tau (2.02±0.15, 1.79±0.05, 1.86±0.06 and1.53±0.04) were decreased(All, P<0.05).ConclusionRAPA can increase Aβ25-35-induced PC12 cells viability, decrease cells apoptosis rates, and have a protective effect on Aβ25-35-induced PC12 cells death.The mechanism of its protective effect may be related to the inhibition of mTOR regulating PI3K/PKB/mTOR signal transduction pathway by negative feedback and the reduction of tau protein hyperphosphorylation.

Effect of Propofol on Expression of Phosphorylated Tau Protein and Beta-amyloid(1-42) Protein in Hippocampus of Offspring Rat / 医药导报

Objective To study the effects of propofol exposure during pregnancy on space cognitive and exploration abilities and expression of phosphorylated tau protein ( P-tau) and beta-amyloid protein[ Aβ(1-42) ] in hippocampus of the offspring. Methods Sprague-Dawley female (n=24) and male rats (n=8) of three months old were mated at the same cage at the ratio of 3:1. Pregnant rats were randomly divided into early group (group E), medium group (group M), late group (group L) and control group ( group C) , with 6 rats in each group. Groups E, M and L received propofol 80 mg · kg-1 · d-1 for 7 consecutive days. Propofol was replaced with equal volume of physiological saline in group C. Learning and memory of the 30-day offspring rats were assessed by using Morris water maze test. Then offspring rats were sacrificed to determine the expression of P-tau and Aβ(1-42) in the hippocampus by ELISA and immunohistochemistry. Results The learning and memory abilities were declined significantly in group E (51. 20±8. 11) s, group M (36. 00±6. 44) s and group L (47. 20±12. 30) s, as compared with group C (65. 60± 7. 23) s (all P<0. 05). The result of immunohistochemistry and ELISA showed that expression of Aβ(1-42) and P-tau in hippocampus was significantly higher in group M than in groups E, L and C[(immunohistochemistry: Aβ(1-42), (27. 38±5. 90) vs. (12. 65± 2. 08), (13. 79±3. 37), and (65. 60±7. 23); P-tau, (26. 35±5. 83) vs. (13. 65±3. 46), (14. 56±3. 82), and (8. 49±1. 20);ELISA:Aβ(1-42) , (88. 6±7. 43) vs. (71. 60±6. 79), (13. 79±3. 37), and (65. 80±6. 28);P-tau, (230. 13±8. 22) vs. (210. 42± 2.20), (210.95±1. 75), and (200. 65±1. 57)] (all P<0.05). Conclusion Multiple propofol injections may impair rat offspring’ s space cognitive abilities and exploration abilities, and the impairment is especially obvious in second trimester of pregnancy, which may be associated with over-expression of P-tau and Aβ(1-42) .

Effects of neuropeptide Y gene transfection on seizure in rat and the expression of phosphorylated Tau protein in the rat hippocampus / 中华行为医学与脑科学杂志

Objective To discuss the effect of gene transfection of rAAV2/1-NPY-EGFP on KA-induced rat seizures,EEG and the expression of hippocampal phosphorylated Tau protein.Methods Altogether 72 healthy male Wistar adult rats were randomly divided into three groups:control group,KA group and NPY group(n=24).The epileptic models were established by the injection of KA 2 μl (0.4 μg/μl) five times to the right side of the hippocampus CA3 area every three days.rAAV2/1-NPY-EGFP group,in which 10 μl of rAAV2/1-NPY-EGFP (titer 5× 1011 v.g./ml) was injected to the lateral ventricle in successful rats chronic model,while KA group was injected with an equal dose of saline.The control group was injected with an equal dose of saline both in the hippocampal CA3 area and the lateral ventricle.The seizure situation,the onset latency and EEG were observed at 2 weeks and 4 weeks after vector injection.Then the expression of phosphorylated Tau protein in hippocampus were detected with Western blotting.Results (1) Scale and latency of each seizure onset in rats of rAAV2/1-NPY-EGFP group (12.13 ± 8.06) had no significant difference at 2 weeks (P＞ 0.05) compared with KA group (12.10± 8.07).The scale of seizure in rats of rAAV2/1-NPY-EGFP group(6.06±3.78) significantly reduced at 4 weeks(P ＜0.05).Latency of seizure onset (79.06±8.83min) significantly increased at 4 weeks(P＜0.05),EEG epileptic discharge frequency and wave amplitude decreased (P＜ 0.05) at 4 weeks.The control group had no seizures.(2)Compared with the control group,the expression of phosphorylated Tau protein in KA group and NPY group significantly increased(P＜0.05) at 2 weeks and 4 weeks,and the expression of phosphorylated Tau protein in the NPY group (1.15±0.16 RQ value) at 4 weeks significantly decreased (P＜0.05) compared with the KA group(1.87± 0.23 RQ value).Conclusion rAAV2/1-NPY-EGFP gene transfection significantly reduces scale of seizure onset and prolongs latency of seizure onset in KA-induced rat model.rAAV2/1-NPY-EGFP gene transfection may play anti-epileptic and neuroprotective effects through inhibiting the expression of phosphorylated Tau protein in hippocampus of KA-induced epileptic rat model.