Epigenetic Modulation on Tau Phosphorylation in Alzheimer's Disease.

Tau hyperphosphorylation is a typical pathological change in Alzheimer's disease (AD) and is involved in the early onset and progression of AD. Epigenetic modification refers to heritable alterations in gene expression that are not caused by direct changes in the DNA sequence of the gene. Epigenetic modifications, such as noncoding RNA regulation, DNA methylation, and histone modification, can directly or indirectly affect the regulation of tau phosphorylation, thereby participating in AD development and progression. This review summarizes the current research progress on the mechanisms of epigenetic modification associated with tau phosphorylation.

Electroacupuncture Alleviates Memory Deficits in APP/PS1 Mice by Targeting Serotonergic Neurons in Dorsal Raphe Nucleus.

OBJECTIVE: Alzheimer's disease (AD) has become a significant global concern, but effective drugs able to slow down AD progression is still lacked. Electroacupuncture (EA) has been demonstrated to ameliorate cognitive impairment in individuals with AD. However, the underlying mechanisms remains poorly understood. This study aimed at examining the neuroprotective properties of EA and its potential mechanism of action against AD. METHODS: APP/PS1 transgenic mice were employed to evaluate the protective effects of EA on Shenshu (BL 23) and Baihui (GV 20). Chemogenetic manipulation was used to activate or inhibit serotonergic neurons within the dorsal raphe nucleus (DRN). Learning and memory abilities were assessed by the novel object recognition and Morris water maze tests. Golgi staining, western blot, and immunostaining were utilized to determine EA-induced neuroprotection. RESULTS: EA at Shenshu (BL 23) and Baihui (GV 20) effectively ameliorated learning and memory impairments in APP/PS1 mice. EA attenuated dendritic spine loss, increased the expression levels of PSD95, synaptophysin, and brain-derived neurotrophic factor in hippocampus. Activation of serotonergic neurons within the DRN can ameliorate cognitive deficits in AD by activating glutamatergic neurons mediated by 5-HT1B. Chemogenetic inhibition of serotonergic neurons in the DRN reversed the effects of EA on synaptic plasticity and memory. CONCLUSION: EA can alleviate cognitive dysfunction in APP/PS1 mice by activating serotonergic neurons in the DRN. Further study is necessary to better understand how the serotonergic neurons-related neural circuits involves in EA-induced memory improvement in AD.

The gut-brain axis: Effect of electroacupuncture pretreatment on learning, memory, and JNK signaling in D-galactose-induced AD-like rats.

Objectives: To examine the effect and potential mechanism of electroacupuncture (EA) pretreatment in spatial learning, memory, gut microbiota, and JNK signaling in D-galactose-induced AD-like rats. Materials and Methods: The AD-like rat model was generated by intraperitoneal injection of D-galactose. Morris water maze was used to determine spatial learning and memory ability, Real-time PCR to determine intestinal flora levels, ELISA to determine tryptophan (Trp) and 5-HT levels in the colon and hippocampal tissues, immunofluorescence to determine 5-HT levels in enterochromaffin cells (ECs), and immunoblotting to determine JNK signaling protein levels in hippocampal tissues. Results: Electroacupuncture pretreatment significantly reduced escape latency and prolonged exploration time in the target quadrant, and significantly increased the relative DNA abundance of Lactobacillus and Bifidobacterium. Meanwhile, electroacupuncture pretreatment also reduced colonic 5-HT levels and increased hippocampal 5-HT levels. Moreover, electroacupuncture pretreatment significantly inhibited hippocampal JNK pathway-related protein expression, including 5-HT6R, JNK, p-JUNK, c-JUN, and p-c-Jun. And the combination of GV20 and ST36 was more effective than single acupoints. Conclusion: Electroacupuncture pretreatment improved the learning and memory ability of D-galactose-induced AD-like model rats, changed the gut microbiota composition, and the mechanism may be related to the gut-brain axis and the JNK signaling pathway. In addition, the combination of GV20 and ST36 could further enhance the efficacy.

Neuroprotective Mechanisms of Puerarin in Central Nervous System Diseases: Update.

Due to global population aging and modern lifestyle changes, the incidence of central nervous system (CNS) disorders, such as neurodegenerative diseases, neuropsychiatric disorders, and cerebrovascular diseases, is increasing and has become a major public health challenge. Current medications commonly used in the clinic are far from satisfactory and may cause serious side effects. Therefore, the identification of novel drugs for the effective management of CNS diseases is very urgent. Puerarin, a highly bioactive ingredient isolated from Pueraria lobata, is known to possess a broad spectrum of pharmacological properties including anti-diabetic, anti-inflammatory, anti-antioxidant, neuroprotective, and cardioprotective features. However, its clinical application is limited due to its poor water solubility. Since puerarin has demonstrated a wide range of neuroprotective functions in various CNS diseases, such as Alzheimer's disease, Parkinson's disease, cerebral ischemia, depression, and spinal cord injury, it has been attracting increasingly intense attention worldwide. In this review, we intend to extensively summarize the research progress on neuroprotective mechanisms of puerarin in recent years and discuss the future directions of its application in CNS disease treatment.

Preventive electroacupuncture ameliorates D-galactose-induced Alzheimer's disease-like inflammation and memory deficits, probably via modulating the microbiota-gut-brain axis.

OBJECTIVES: We aimed to observe the effects of preventive electroacupuncture (EA) on the microbiota-gut-brain axis and spatial learning and memory deficits and to investigate the possible mechanism using D-galactose (D-gal)-induced aging rats. MATERIALS AND METHODS: D-gal was intraperitoneally injected to establish the aging model. We used Morris water maze to detect spatial learning and memory function of rats. RT-PCR was applied to test targeted gut microbes. The expression of zonula occludens-1 (ZO-1) and Toll-like receptor 4 (TLR4)/nuclear factor (NF)-κB pathway proteins were detected by Western blotting. ELISA was employed to evaluate the level of lipopolysaccharides (LPS), diamine oxidase (DAO) and S-100ß. Additionally, we observed ionized calcium-binding adapter molecule-1 (Iba-1) expression in the hippocampal CA1 area by immunofluorescence. RESULTS: Morris water maze test showed decreased mean escape latency and increased target quadrant time after EA treatment. The gut microbiota composition has been modified in EA treated rats. Molecular examination indicated that expression of ZO-1 was improved and the the concentration of LPS in blood and hippocampus were reduced in EA treated rats. Further, we observed an inhibition of activated microglia and TLR4/NF-κB pathway in EA groups. CONCLUSION: Preventive EA may alleviate the impairments of the microbiota-gut-brain axis and spatial learning and memory in aging, and the mechanism may be related to the inhibition of TLR4/NF-kB signaling pathway. The combination of acupoints GV20 and ST36 can enhance the therapeutic effect in aging rats.

Acupuncture and Related Therapies for the Cognitive Function of Alzheimer's Disease: A Network Meta-Analysis.

Background: Acupuncture and acupuncture-related therapies are effective for Alzheimer's disease (AD), therefore, we aimed to compare and rank the interventions that mainly focus on acupuncture-related therapies in the treatment of patients with mild to moderate AD. Methods: We used network meta-analysis to evaluate the direct and indirect evidence shown in randomized controlled trials of AD. The data were analyzed using RavMan manager, Stata, and WinBUGS software after two researchers independently screened the literature, extracted the data, and assessed the risk of bias in the included studies. Results: We analyzed a total of 36 eligible studies, including 2712 patients, involving 14 types of acupuncture-related therapies and comprehensive therapies. For Mini-Mental State Examination (MMSE), acupuncture (ACU) combined with cognitive and memory training (Training) was more effective than ACU, ACU+Chinese herb (CH), ACU+Donepezil (DON), CH, DON, DON+Nimodipine (NIM), Music therapy (Music), NIM, Placebo, and Training (P<0.05), while ACU+CH was batter than CH (P<0.05), and ACU+DON+NIM was better than DON+NIM (P<0.05). For Alzheimer's Disease Assessment Scale-Cognitive section (ADAS-cog), ACU was more effective than DON and placebo (P<0.05). For Activities of Daily Living (ADL), ACU+DON was better than CH, DON, NIM, and Placebo (P<0.05). For the clinical effectiveness rate, ACU, ACU+CH, ACU+CH+DON, ACU+CH+DON+NIM, ACU+DON, CH, NIM were all more effective than DON+NIM (P<0.05), while ACU and ACU+CH were better than DON (P<0.05). The comprehensive ranking results show that ACU+training and ACU have the highest ranking probability. Conclusion: ACU+Training and ACU may be the best therapies to improve the cognitive function of patients with mild to moderate AD, while the combination of acupuncture-related therapies and other therapies has a higher overall benefit.

Preventive electroacupuncture reduces cognitive deficits in a rat model of D-galactose-induced aging.

Acupuncture can reduce cognitive deficits in Alzheimer's disease. However, whether electroacupuncture can prevent or alleviate the cognitive deficits in animal models of aging remains poorly understood. Studies have shown that disordered epigenetic modifications play a critical role in age-related cognitive decline. Therefore, we hypothesized that preventive electroacupuncture might improve cognitive functions during aging by regulating epigenetic modifications. A rat model of aging was produced by intraperitoneal injection of 120 mg/kg D-galactose for 8 weeks. Baihui and Shenshu acupoints were stimulated by electroacupuncture for 8 weeks from the first day of D-galactose administration. Preventive electroacupuncture alleviated memory impairment, decreased tau hyperphosphorylation, and reduced glycogen synthase kinase-3ß protein and mRNA expression levels in the brainstem dorsal raphe nucleus, where intracellular neurofibrillary tangle lesions first occur. In addition, the DNA methylation level in the promoter region of the glycogen synthase kinase-3ß gene was increased. The effects of preventive electroacupuncture were stronger than those of preventive acupuncture. Intraperitoneal injection of 0.4 mg/kg 5-aza-2'-deoxycytidine, an inhibitor of DNA methyltransferase that blocks epigenetic modifications, antagonized the effects of preventive electroacupuncture. Our results suggest that preventive electroacupuncture treatment alleviates cognitive impairment in aging rats probably by affecting the epigenetic modification of the glycogen synthase kinase-3ß gene in the dorsal raphe nucleus. This study was approved by the Animal Ethics Committee of Hubei University of Chinese Medicine, China (approval No. HUCMS201712001) on November 28, 2017.

[Effect of electroacupuncture on cyclin-dependent kinase 5 and Tau protein in hippocampus of SAMP8 mice].

OBJECTIVE: To observe the effect of electroacupuncture (EA) and manual acupuncture (MA) on learning-memory ability, changes of ultrastructure of neurons and expression of CDK5 and Tau proteins in hippocampus of SAMP8 mice，so as to explore its mechanisms underlying improvement of Alzheimer's disease (AD)．. METHODS: A total of 45 male SAMP8 mice were randomly divided into model, EA and MA groups, with 15 mice in each group. The other 15 SAMR1 mice were used as the normal group. In the EA group, EA (2 Hz, 1 mA) was applied to bilateral "Shenshu"(BL23) and manual acupuncture was applied to "Baihui"(GV20) for 20 min. In the MA group, MA was applied to GV20 and bilateral BL23 for 20 min. Both group were treated once a day for 31 days, and with an interval of one day between every two 7 days. Morris water maze was performed to assess the animals' learning-memory ability. The morphological changes of hippocampal neurons were observed under transmission electron microscopy. The expression levels of CDK5, p25 and Tau-5 proteins in the hippocampus were detected by immunohistochemistry and Western blot, separately. RESULTS: ①Compared with the normal group, the average escape latency of Morris water maze test was prolonged in the model group(P<0.05, P<0.01), duration of swimming in the original platform quadrant and the number of original platform crossing were significantly shorter and less respectively (P<0.01). Compared with the model group, the average escape latency in the EA group was shortened (P<0.05, P <0.01), the duration of swimming in the original platform quadrant and the number of original platform crossing were significantly prolonged and increased (P<0.01); The average escape latency in the MA group was shortened (P<0.05, P <0.01)，and the duration of swimming in the original platform quadrant was prolonged (P<0.05). Compared with the EA group, the average escape latency of the MA group was prolonged (P<0.05), the duration of swimming in the original platform quadrant was shortened(P<0.05). ②Transmission electron microscopy revealed that the neurons in the hippocampal CA1 area had irregular shape and vague structure, reduction in size and number of mitochondria accompanied with swelling, and malformed changes of mitochondrial crest in the model group, which was relatively milder in both EA and MA groups. ③The expression levels of hippocampal Tau-5, p25 and CDK5 proteins were significantly up-regulated in the model group in contrast to the normal group (P<0.01, P<0.05), and obviously down-regulated in both EA and MA groups relevant to the model group (P<0.05, P<0.01). Compared with the EA group, the expression levels of p25 and CDK5 proteins were significantly increased in the MA group (P<0.05). CONCLUSION: EA of BL23 can improve the learning-memory ability in SAMP8 mice, which is associated with its effect in down-regulating the expression of hippocampal CDK5, p25 and Tau-5 proteins.

Epigenetic Regulation of Amyloid-beta Metabolism in Alzheimer's Disease.

Senile plaques (SPs) are one of the pathological features of Alzheimer's disease (AD) and they are formed by the overproduction and aggregation of amyloid-beta (Aß) peptides derived from the abnormal cleavage of amyloid precursor protein (APP). Thus, understanding the regulatory mechanisms during Aß metabolism is of great importance to elucidate AD pathogenesis. Recent studies have shown that epigenetic modulation-including DNA methylation, non-coding RNA alterations, and histone modifications-is of great significance in regulating Aß metabolism. In this article, we review the aberrant epigenetic regulation of Aß metabolism.

[Effect of pretreatment of acupuncture on learning-memory ability and related protein of NLRP3 inflammasome in hippocampus in Alzheimer's disease like rats].

OBJECTIVE: To observe the effect of pretreatment of acupuncture on the expression of nucleotide-binding oligomerization domain-like receptor 3(NLRP3), Caspase-1, interleukin1ß(IL-1ß) and the number of activated microglia (MG) in the hippocampus in Alzheimer's disease (AD) like rats, so as to explore the mechanism of pretreatment of acupuncture in preventing and treating AD. METHODS: A total of 36 SD rats were randomly divided into a blank group, a model group and an electroacupuncture (EA) group, 12 rats in each group. The AD like rat model was established by 8-week continuous intraperitoneal injection of D-galactose (120 mg·kg-1·d-1) in the model group and the EA group. The rats in the EA group were intervened with EA at "Baihui" (GV 20) and "Zusanli" (ST 36), continuous wave, 5 Hz in frequency, 1 mA in intensity, 20 min each intervention, once a day, for 8 weeks. After the intervention, the spatial learning-memory ability was evaluated by the Morris water maze test. The expression levels of NLRP3, Caspase-1 and IL-1ß protein in hippocampus were detected by Western blot method. The number of activated MG in hippocampus was detected by immunofluorescence labeling method. RESULTS: Compared with the blank group, the average escape latency was prolonged (P<0.01), the number of platform crossing was reduced (P<0.01), and the exploration time of target quadrant was shortened (P<0.01) in the model group. Compared with the model group, the average escape latency was shortened (P<0.01), the number of platform crossing was increased (P<0.01), and the exploration time of target quadrant was prolonged (P<0.01) in the EA group. Compared with the blank group, the expression levels of NLRP3, Caspase-1, IL-1ß protein in hippocampus were increased (P<0.01), and the number of activated MG was increased (P<0.01) in the model group. Compared with the model group, the expression levels of NLRP3, Caspase-1, IL-1ß protein in hippocampus were decreased (P<0.01), and the number of activated MG was decreased (P<0.05) in the EA group. CONCLUSION: Pretreatment of acupuncture could prevent and treat the learning-memory dysfunction in AD like rats, and its mechanism may be related to the inhibition of NLRP3 inflammatsome related protein and MG activation.

Experimental Evidence of the Benefits of Acupuncture for Alzheimer's Disease: An Updated Review.

As the global population ages, the prevalence of Alzheimer's disease (AD), the most common form of dementia, is also increasing. At present, there are no widely recognized drugs able to ameliorate the cognitive dysfunction caused by AD. The failure of several promising clinical trials in recent years has highlighted the urgent need for novel strategies to both prevent and treat AD. Notably, a growing body of literature supports the efficacy of acupuncture for AD. In this review, we summarize the previously reported mechanisms of acupuncture's beneficial effects in AD, including the ability of acupuncture to modulate Aß metabolism, tau phosphorylation, neurotransmitters, neurogenesis, synapse and neuron function, autophagy, neuronal apoptosis, neuroinflammation, cerebral glucose metabolism, and brain responses. Taken together, these findings suggest that acupuncture provides therapeutic effects for AD.

Acupuncture and related therapies for hyperlipidemia: A protocol for systematic review and network meta-analysis.

OBJECTIVE: To compare and rank the clinical effects of different acupuncture and acupuncture-related therapies on patients with hyperlipidemia. METHODS: We used Network Meta-Analysis (NMA) to evaluate the direct and indirect evidence from relevant studies. Three English and 4 Chinese databases were searched to collect randomized controlled trials (RCT) of acupuncture and related therapies in the treatment of hyperlipidemia. The data were analyzed using Stata15.0 and WinBUGS1.4.3 software after 2 researchers independently screened the literature, extracted the data, and assessed the risk of bias in the included studies. RESULTS: Based on the current evidence, we comprehensively compare the pros and cons of various acupuncture-related therapies, rank the efficacy of various acupuncture-related therapies compared with statins in the treatment of hyperlipidemia, and summarize the best acupuncture intervention methods or combinations. CONCLUSION: This study will provide new evidence for the safety and effectiveness of acupuncture-related therapies in the treatment of hyperlipidemia, and may be helpful for clinicians, hyperlipidemia patients, and clinical guideline makers to choose the optimal combination of acupuncture for the treatment of hyperlipidemia. REGISTRATION NUMBER: INPLASY2020100100.

[Effects of electroacupuncture on cognitive function and neuronal autophagy in rats with D-galactose induced Alzheimer's disease].

OBJECTIVE: To observe the effect of electroacupuncture at "Baihui"(GV20) and "Shenshu"(BL23) on the expression of autophagy-related proteins in the hippocampus of rats with Alzheimer's disease (AD)，so as to explore its underlying mechanisms on improvement of AD. METHODS: Forty-eight male SD rats were randomly divided into blank control group, model group, electroacupuncture group and sham electroacupuncture group, with 12 rats in each group. The AD rat model was establish by intraperitoneal injection of D-galactose for 6 weeks. Rats in the electroacupuncture group received electroacupuncture (50 Hz, 1 mA)at GV20 and BL23 for 20 min each time after daily intraperitoneal injection. Rats in the sham electroacupuncture group received acupuncture at the local skin of GV20 and BL23 without electricity. After the intervention, Morris water maze and open field test were used to evaluate the learning and cognitive ability of rats in each group. The transmission electron microscope was used to observe the numerical density of synaptic in hippocampus, and the immunohistochemical staining was used to observe the paired helical filament protein-1 (PHF-1) in the hippocampus. Western blot was used to detected the expression of autophagy-related proteins phosphoinositide-3-kinase (PI3K), protein kinase B (AKT), phosphorylated AKT (p-AKT), mammalian target of rapamycin (mTOR) in the hippocampus. RESULTS: Compared with the blank control group, the escape latency of the rats in the model group increased from day 2 to day 5 (P<0.01), and the ratio of the time through the quadrant of the original platform reduced （P<0.01）, in the open field test the distance of exercise, the number of uprights and the rate of exercise time in the central area decreased (P<0.01), meanwhile the density of hippocampus synapses decreased (P<0.01), the positive expression of PHF-1 and the relative expression of PI3K, AKT, p-AKT, and mTOR all increased (P<0.01). Compared with the model group, the escape latency of rats in the electroacupuncture group was shortened from day 2 to day 5 (P<0.01), and the ratio of the time through the quadrant of the original platform meanwhile, the distance of the open field test, the number of uprights, and the rate of central area exercise time up-regulated (P<0.01), the numerical density of hippocampus synatic increased (P<0.01), the positive expression of PHF-1 and the relative expression of PI3K, AKT, p-AKT, and mTOR all down-regulated (P<0.01). Compared with the model group, the expression of PI3K in the sham electroacupuncture group decreased (P<0.05). CONCLUSION: Electroacupuncture can improve learning and memory and cognitive impairment in AD rats, which may be associated with its effects in regulation of hippocampal autophagy and removal of neurofibrillary tangles by suppressing PI3K/AKT/mTOR signaling pathway.

Preventive Electroacupuncture Ameliorates D-Galactose-Induced Alzheimer's Disease-Like Pathology and Memory Deficits Probably via Inhibition of GSK3ß/mTOR Signaling Pathway.

Acupuncture has been practiced to treat neuropsychiatric disorders for a thousand years in China. Prevention of disease by acupuncture and moxibustion treatment, guided by the theory of Chinese acupuncture, gradually draws growing attention nowadays and has been investigated in the role of the prevention and treatment of mental disorders such as AD. Despite its well-documented efficacy, its biological action remains greatly invalidated. Here, we sought to observe whether preventive electroacupuncture during the aging process could alleviate learning and memory deficits in D-galactose-induced aged rats. We found that preventive electroacupuncture at GV20-BL23 acupoints during aging attenuated the hippocampal loss of dendritic spines, ameliorated neuronal microtubule injuries, and increased the expressions of postsynaptic PSD95 and presynaptic SYN, two important synapse-associated proteins involved in synaptic plasticity. Furthermore, we observed an inhibition of GSK3ß/mTOR pathway activity accompanied by a decrease in tau phosphorylation level and prompted autophagy activity induced by preventive electroacupuncture. Our results suggested that preventive electroacupuncture can prevent and alleviate memory deficits and ameliorate synapse and neuronal microtubule damage in aging rats, which was probably via the inhibition of GSK3ß/mTOR signaling pathway. It may provide new insights for the identification of prevention strategies of AD.

[Effect of acupuncture on the ultrastructure of neurons and astrocytes in the hippocampal dentate gyrus in rats with Alzheimer's disease induced by Aß1-42].

OBJECTIVE: To observe the effects of acupuncture at "Baihui" (GV 20) and "Shenshu" (BL 23) on the ultrastructure of hippocampal dentate gyrus in rats with Alzheimer's disease. METHODS: Forty SPF Wistar male rats were randomly divided into a normal group, a sham operation group, a model group and an acupuncture group, 10 rats in each one. The rats in the model group and the acupuncture group were treated with injection of 5 µL Aß1-42 at bilateral hippocampus, while the rats in the sham operation group were treated with injection of 5 µL 0.9% NaCl. Three days after modeling, the rats in the acupuncture group were treated with acupuncture at "Baihui" (GV 20) and "Shenshu" (BL 23) for 20 min, once a day, six treatments constituted a course, and totally two courses were given with an interval of 1 day between courses. The rats in the other groups received normal diet and no treatment was given. Before modeling, four days after modeling and after treatment, water maze test was performed to observe the escape latency and the number of crossing platforms. The hippocampal dentate gyrus was collected and transmission electron microscope was applied to observe the ultrastructure changes of neurons and astrocytes. RESULTS: ①Four days after modeling, compared with the normal group and the sham operation group, the escape latency was significantly prolonged and the number of crossing platforms was reduced in the model group (all P<0.01); after treatment, compared with the model group, the escape latency was significantly reduced and the number of crossing platforms was increased in the acupuncture group (both P<0.01). ②In the normal group and the sham operation group, the morphology of neurons and astrocytes was intact, the nuclear and membrane structure were clear, and the morphology of organelles such as mitochondria, endoplasmic reticulum and lysosomes was normal. In the model group, the morphology of neurons was irregular, the nucleus was severely constricted with edema in the cytoplasm, the color of heterochromatin was deepened, the endoplasmic reticulum was expanded, the granulation was removed and the number of mitochondria was decreased, even with malformed-like change in mitochondrial cristae; there was severe edema around astrocytes, few organelles in the cytoplasm, severe swelling of mitochondria and mild expansion of the endoplasmic reticulum. In the acupuncture group, the edema of the neuron and astrocytes was still evident, and the mitochondrial was mildly swollen but relieved compared with that in the model group, and there were no obvious abnormalities in neuronal endoplasmic reticulum and ribosomes. CONCLUSION: Acupuncture could improve the ultrastructure of neurons and astrocytes in the hippocampal dentate gyrus in rats with Alzheimer's disease induced by Aß1-42.

Effects of Acupuncture on Alzheimer's Disease: Evidence from Neuroimaging Studies.

As the worldwide population ages, the prevalence of Alzheimer's disease (AD) increases. However, the results of promising medications have been unsatisfactory. Chinese acupuncture has a long history of treating dementia, but lack of evidence from well-designed randomized controlled trials that validate its efficacy and safety, as well as its lack of clear underlying mechanisms, contribute to its limited application in clinical practice. In recent years, brain imaging technologies, such as functional magnetic resonance imaging and positron emission tomography, have been used to assess brain responses to acupuncture in a dynamic, visual, and objective way. These techniques are frequently used to explore neurological mechanisms of responses to acupuncture in AD and provide neuroimaging evidence as well as starting points to elucidate the possible mechanisms. This review summarizes the existing brain imaging evidence that explains the effects of acupuncture for AD and analyzes brain responses to acupuncture at cognitive-related acupoints [Baihui (GV 20), Shenmen (HT 7), Zusanli (ST 36), Neiguan (PC 6), and Taixi (KI 3)] from perspectives of acupoint specificity and acupoint combinations. Key issues and directions to consider in future studies are also put forward. This review should deepen our understanding of how brain imaging studies can be used to explore the underlying mechanisms of acupuncture in AD.

[Effect of pre-acupuncture at Neiguan (PC 6) and Zusanli (ST 36) on exercise-induced fatigue].

OBJECTIVE: To observe the therapeutic effect of pre-acupuncture at Neiguan (PC 6) and Zusanli (ST 36) on exercise-induced fatigue. METHODS: A total of 50 subjects were divided into an observation group and a control group by random number table method, 25 cases in each one. In the observation group, acupuncture was applied at Neiguan (PC 6) and Zusanli (ST 36) before exercise, once a day, consecutive 5-day treatment was required. In the control group, there was no intervention. The subjective fatigue perception score, serum levels of lactate and lactate dehydrogenase, heart rate and oxygen saturation before and after exercise were observed in the two groups. RESULTS: Compared before exercise, the subjective fatigue perception scores, serum levels of lactate and lactate dehydrogenase and heart rates after exercise were increased in the two groups (P<0.05, P<0.01), and the subjective fatigue perception score, serum levels of lactate and lactate dehydrogenase and heart rate after exercise in the observation group were lower than the control group (P<0.05, P<0.01). There was no significant difference in oxygen saturation before and after exercise in the two groups，there was no significant difference in oxygen saturation after exercise between the two groups (P>0.05). CONCLUSION: Pre-acupuncture at Neiguan (PC 6) and Zusanli (ST 36) can effectively reduce the subjective fatigue perception score，serum levels of lactate and lactate dehydrogenase and heart rate to improve exercise-induced fatigue.

High-frequency (50 Hz) electroacupuncture ameliorates cognitive impairment in rats with amyloid beta 1-42-induced Alzheimer's disease.

Acupuncture has been shown to ameliorate cognitive impairment of Alzheimer's disease. Acupoints and stimulation frequency influence the therapeutic effect of electroacupuncture. Rat models of Alzheimer's disease were established by injecting amyloid beta 1-42 (Aß1-42) into the bilateral lateral ventricles. Electroacupuncture at 2, 30, and 50 Hz was carried out at Baihui (GV20; 15° obliquely to a depth of 2 mm) and Shenshu (BL23; perpendicularly to 4-6 mm depth), once a day for 20 minutes (each), for 15 days, taking a break every 7 days. The Morris water maze test was conducted to assess the learning and memory. The expression levels of glycogen synthase kinase-3ß (GSK-3ß), pSer9-GSK-3ß, pTyr216-GSK-3ß, amyloid precursor protein and Aß1-40 in the hippocampus were determined by western blot assay. Results demonstrated that electroacupuncture treatment at different frequencies markedly improved learning and memory ability, increased synaptic curvatures, decreased the width of synaptic clefts, thickened postsynaptic densities, and downregulated the expression of GSK-3ß, amyloid precursor protein, and Aß1-40. pSer9-GSK-3ß expression markedly decreased, while pTyr216-GSK-3ß expression increased. High-frequency (50 Hz) electroacupuncture was more effective than low (2 Hz) or medium-frequency (30 Hz) electroacupuncture. In conclusion, electroacupuncture treatment exerts a protective effect against Aß1-42-induced learning and memory deficits and synapse-ultrastructure impairment via inhibition of GSK-3ß activity. Moreover, high-frequency electroacupuncture was the most effective therapy.

High-frequency electroacupuncture evidently reinforces hippocampal synaptic transmission in Alzheimer's disease rats.

The frequency range of electroacupuncture in treatment of Alzheimer's disease in rats is commonly 2-5 Hz (low frequency) and 50-100 Hz (high frequency). We established a rat model of Alzheimer's disease by injecting ß-amyloid 1-42 (Aß1-42) into the bilateral hippocampal dentate gyrus to verify which frequency may be better suited in treatment. Electroacupuncture at 2 Hz or 50 Hz was used to stimulate Baihui (DU20) and Shenshu (BL23) acupoints. The water maze test and electrophysiological studies demonstrated that spatial memory ability was apparently improved, and the ranges of long-term potentiation and long-term depression were increased in Alzheimer's disease rats after electroacupuncture treatment. Moreover, the effects of electroacupuncture at 50 Hz were better than that at 2 Hz. These findings suggest that high-frequency electroacupuncture may enhance hippocampal synaptic transmission and potentially improve memory disorders in Alzheimer's disease rats.

[Protective mechanism of acupuncture-moxibustion on hippocampal neuron mitochondria in rats with Alzheimer's disease].

OBJECTIVE: To observe effects of acupuncture and moxibustion on ultrastructure and silent information regulator 1 (SIR1) in hippocampal neuron mitochondria in rats with Alzheimer's disease (AD) in order to explore its possible effective mechanism during the process of protecting mitochondria. METHODS: Eighty Wistar rats were randomly divided into a normal group, a sham operation group, a model group and an acupuncture group, 20 rats in each one. The AD model was established in the model group and acupuncture group with injection of Amyloid beta Protein Fragment1-14 (Abeta1-42) into the hippocampus. Acupuncture and moxibustion was applied at "Baihui" (GV 20) and "Shenshu" (BL 23) in the acupuncture group, once a day, seven days as a treatment course and totally two course were required. The rest groups were all fed with normal diet, without any treatment. The transmission electron microscopy, immunohistochemistry and immunoblotting technique were respectively adapted to measure ultrastructure and level of STR1 in hippocampal neuron mitochondria in AD rats. RESULTS: Compared with the model group, the ultrastructure in hippocampal neuron mitochondria in the acupuncture group was effectively improved. The average optical density of SIR1 in hippocampus was 0.21 +/- 0.10 and the gray value was 136.82 +/- 47.42 in the model group, which were obviously lower than 0.47 +/- 0.09 and 281.44 +/- 57.98 in the normal group (both P < 0.01). However, levels of SIR1 in the acupuncture group, they were 0.32 +/- 0.11 and 199.52 +/- 58.12, which were significantly increased compared with those in the model group (both P < 0.05). CONCLUSION: The reinforcing-kidney and regulating-Governor Vessel method of acupuncture and moxibustion for AD could improve ultrastructure of mitochondria and increase levels of SIR1 to achieve the aim of recovering injury of mitochondria and protecting function of mitochondria.