Effect of electroacupuncture on proBDNF/mBDNF and synaptic plasticity in rats with learning and memory impairment after cerebral ischemia-reperfusion. / ç”µé’ˆå¯¹è„‘ç¼ºè¡€å†çŒæ³¨å­¦ä¹ è®°å¿†éšœç¢å¤§é¼ æµ·é©¬è„‘æºæ€§ç¥žç»è¥å »å› å­è½¬åŒ–å’Œçªè§¦å¯å¡‘æ€§çš„å½±å“.

OBJECTIVES: To observe the effect of electroacupuncture (EA) at "Baihui" (GV20) and "Shenting" (GV24) on the rats' behavior and the transforming precursor of brain-derived neurotrophic factor (proBDNF) into mature brain-derived neurotrophic factor (mBDNF) in the hippocampus of rats with learning and memory impairment induced by cerebral ischemia-reperfusion (IR), so as to explore its mechanisms underlying improvement of learning and memory ability. METHODS: SD rats were randomly divided into blank, sham operation, model, and EA groups, with 6 rats in each group. The model of IR was established by occlusion of the middle cerebral artery. EA (1 Hz/20 Hz) was applied to GV24 and GV20 for 30 min, once daily for 14 days. The neurological function was evaluated according to the Zea Longa's score criteria 24 h after modeling and after intervention. Morris water maze test was used to detect the learning and memory function of the rats. TTC staining was used to evaluate the cerebral infarction volume on the affected side. The protein expression levels of proBDNF, mBDNF, tissue plasminogen activator (tPA), tyrosine kinase receptor B (TrkB) and p75 neurotrophin receptor (p75NTR) in hippocampal tissue were detected by Western blot. RESULTS: Compared with the sham operation group, the neurological function score, the percentage of cerebral infarction volume and the expression levels of proBDNF and p75NTR protein in hippocampus were increased (P<0.01), while the times of crossing the original platform and the total distance in the target quadrant, the expression levels of mBDNF, TrkB and tPA protein and the ratio of mBDNF/proBDNF were decreased (P<0.01, P<0.05) in the model group. Compared with the model group, the neurological function score, the percentage of cerebral infarction volume, and the expression levels of proBDNF and p75NTR protein in hippocampus were decreased (P<0.01, P<0.05), while the times of crossing the original platform, the total distance in the target quadrant, and the expression levels of mBDNF, TrkB and tPA protein and the ratio of mBDNF/proBDNF were increased (P<0.05, P<0.01) in the EA group. CONCLUSIONS: EA can alleviate learning and memory impairment in IR rats, which may be related to its function in up-regulating the expression of tPA protein and promoting the transformation of proBDNF to mBDNF, thus improving the synaptic plasticity.

Folic acid supplementation improved nicotine withdrawal-induced of memory loss via affecting oxidative status, inflammatory response, cholinergic activity, BDNF and amyloid-B in adolescent male rat.

BACKGROUND: The present study aimed to assess whether folic acid (FA) have potential to prevent memory impairment caused by nicotine (Nico) withdrawal in adolescent male rats. METHODS AND MATERIALS: The experiments were divided into 7 groups: 1) vehicle, 2) Nico (Nico 2 mg/kg injection from 21 to 42 days of ages), 3-5) Nico FA5/10/15 mg/kg (received Nico from 21 to 42 days of ages and received FA at three doses 5, 10 and 15 mg/kg 43-63 days of ages), and 6) received normal saline from 21 to 42 days of age after that received FA 15 mg/kg by oral gavage from 43 to 63 days of age. At 64-69 days of ages, behavioral tests related to memory including Morris Water Maze (MWM) and Object Recognition Test (ORT) were performed and related biochemical analysis including the hippocampal levels of oxidative stress markers, inflammatory indices, brain-derived neurotrophic factor (BDNF), nitrite, amyloid-B and acetylcholinesterase [1] were measured. RESULTS: Results showed that nicotine exposure in adolescence followed by withdrawal dramatically impaired learning and memory performance along with affecting a variety of biochemical markers in the hippocampal tissues. In addition, it was observed that administration of FA significantly ameliorated Nico withdrawal-induced adverse effects through restoration of the mentioned biochemical disturbances. CONCLUSION: The present study and other relevant researches demonstrated that FA as a well-known, inexpensive, and safe supplement has strong potential to either prevent or ameliorate the detrimental effect of Nico withdrawal. However, further investigation is required to be more elucidated the precise mechanisms underlying memory impairment-induced by Nico withdrawal.

[Electroacupuncture improves learning and memory impairment and enhances hippocampal synaptic plasticity through BDNF/TRKB/CREB signaling pathway in cerebral ischemia-reperfusion injury rats].

OBJECTIVE: To observe the effect of electroacupuncture on brain-derived neurotrophin factor (BDNF) / tyrosine kinase receptor B (TRKB) / cyclic adenosine monophosphate response element binding protein (CREB) pathway, synaptic plasticity marker protein and synaptic ultrastructure in the hippocampus of rats with learning and memory impairment induced by cerebral ischemia reperfusion (IR), so as to explore its mechanisms underlying improvement of cognitive impairment after stroke. METHODS: SD rats were randomly divided into blank, sham operation, model, and EA groups, with 12 rats in each group. The model of IR was established by occlusion of the middle cerebral artery. EA (2 Hz/10 Hz, 1-3 mA) was applied to "Shenting" (GV24) and "Baihui" (GV20) for 30 min, once daily for 14 days. The neurological function was evaluated according to the Zea Longa's score criteria. Morris water maze test was used to detect the learning and memory function of the rats. Nissl staining was used to observe the pathological morphology of the hippocampus. Transmission electron microscopy was used to observe the ultrastructure of the syna-pse in the hippocampus, the synaptic gap width and postsynaptic dense substance (PSD) thickness were measured. Immunofluorescence staining was used to observe the positive expression levels of BDNF, PSD-95 and synaptophysin (SYN) in hippocampal CA1 region. The protein expression levels of BDNF, TRKB, CREB, PSD-95, and SYN in hippocampal tissue were detected by Western blot. RESULTS: Compared with the sham operation group, the neurological function score and escape latency (EL) were significantly increased (P<0.01), the times of crossing the original platform were decreased (P<0.01), the number of neurons in the CA1 area of the hippocampus was reduced, with incomplete morphology, widened synaptic gaps and significantly decreased PSD thickness (P<0.01), the positive expressions of BDNF, PSD-95, SYN and the protein expression levels of BDNF, TRKB, CREB, PSD-95, SYN were significantly decreased (P<0.01) in the model group. Compared with the model group, the neurological function scores and EL on the 12th and 13th day were decreased (P<0.01, P<0.05), the times of crossing the original platform were increased (P<0.01), the morphology of hippocampal CA1 neurons improved, the synaptic gaps was decreased (P<0.01), the PSD thickness was significantly increased (P<0.01), the positive expressions of BDNF, PSD-95, SYN, and the protein expression levels of BDNF, TRKB, CREB, PSD-95, SYN were increased (P<0.05, P<0.01) in the EA group. CONCLUSION: EA can alleviate cognitive impairment in IR rats, which may be related to its function in up-regulating the proteins of BDNF/TRKB/CREB pathway, promoting the expressions of synaptic plasticity marker proteins PSD-95 and SYN, thus improving the synaptic plasticity.

Acanthopanax senticosus extract alleviates radiation-induced learning and memory impairment based on neurotransmitter-gut microbiota communication.

BACKGROUND: Acanthopanax senticosus (AS) is a medicinal and food plant with many physiological functions, especially nerve protection. Its extract has many functional components, including polysaccharides, flavonoids, saponins, and amino acids. Our previous study indicated that AS extract protected against nerve damage caused by radiation. However, little is known about the gut-brain axis mechanism of AS and its impact on radiation-induced learning and memory impairment. METHOD: In 60 Co-γ ray-irradiated mice, we investigated the changes in behavior, neurotransmitters and gut microbiota after different days of administration of AS extract as a dietary supplement. RESULTS: The AS extract improved learning and memory ability in mice, and the neurotransmitter levels in the hippocampus and colon started to change from the 7th day, which accompanied changes of the gut microbiota, a decreased abundance of Helicobacter on the 7th day and an increased abundance of Lactobacillus on the 28th day. Among the marker bacteria, Ruminococcus and Clostridiales were associated with 5-HT synthesis, and Streptococcus were associated with 5-HT and ACH synthesis. In addition, the AS extract increased the tight junction protein, inhibited inflammation levels in colon, and even increased the relative protein expression of BDNF and NF-κB and decreased the relative protein expression of IκBα in the hippocampus of irradiated mice. CONCLUSION: These results will lay the foundation for further study on the mechanism of the gut-brain axis of AS in preventing radiation-induced learning and memory impairment.

[Research progress on the modulation mechanism of electroacupuncture for learning and memory impairment after ischemic stroke].

Electroacupuncture may play a role in treatment of learning and memory impairment after ischemic stroke by regulating phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt) signaling pathway, cyclic adenosine monophosphate (cAMP)-dependent protein kinase A (PKA)/cAMP response element binding protein (CREB) signaling pathway, nerve growth factor (NGF)/tyrosine kinase-A (TrkA) signaling pathway, Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway, Notch signaling pathway, erythropoietin-producing hepatocyte (Eph)/ephrin signaling pathway. The interactions among these pathways should be further explored in treatment of learning and memory impairment after ischemic stroke.

Humulus lupulus L. extract and its active constituent xanthohumol attenuate oxidative stress and nerve injury induced by iron overload via activating AKT/GSK3ß and Nrf2/NQO1 pathways.

Hops, the dried female clusters from Humulus lupulus L., have traditionally been used as folk medicines for treating insomnia, neuralgia, and menopausal disorders. However, its pharmacological action on iron overload induced nerve damage has not been investigated. This study aims to evaluate the protective effects of hops extract (HLE) and its active constituent xanthohumol (XAN) on nerve injury induced by iron overload in vivo and in vitro, and to explore its underlying mechanism. The results showed that HLE and XAN significantly improved the memory impairment of iron overload mice, mainly manifested as shortened latency time, increased crossing platform times and spontaneous alternation ratio, and increased the expression of related proteins. Additionally, HLE and XAN significantly increased superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activities, and remarkably decreased malondialdehyde (MDA) level in hippocampus. Also, HLE and XAN apparently reduced reactive oxygen species (ROS) content of PC12 cells induced by iron dextran (ID), and improved the oxidative stress level. Moreover, HLE and XAN significantly upregulated the expression of nuclear factor E2-related factor (Nrf2), NAD(P)H quinone oxidoreductase (NQO1), heme oxygenase-1 (HO-1), SOD, phosphorylated AKT (p-AKT), and phosphorylated GSK3ß (p-GSK3ß) both in hippocampus and PC12 cells. These findings demonstrated the protective effect of HLE and XAN against iron-induced memory impairment, which is attributed to its antioxidant profile by activation of AKT/GSK3ß and Nrf2/NQO1 pathways. Also, it was suggested that hops could be a potential candidate for iron overload-related neurological diseases treatment.

Choline alleviated perinatal fluoride exposure-induced learning and memory impairment through α4ß2 nAChRs and α7 nAChRs in offspring mice.

Fluoride pollution is widely present in the living environment. As a critical period of brain development, the perinatal period is extremely vulnerable to fluoride. Studies have found that choline can protect the brain's memory and enhance the ability to focus. However, the effect of choline on perinatal fluoride-induced nerve damage remains unclear. Therefore, 32 Kunming newly conceived female mice and their offspring mice were randomly divided into control, NaF, LC + NaF, and HC + NaF groups, and the HE staining, Y-maze test, RT-PCR, western blotting, immunohistochemistry, etc. were used in this study. The results showed that fluoride decreased the brain organ coefficients and brain protein content (p < 0.05, p < 0.01), and caused histomorphological damage in the hippocampus and cortex, which suggested that fluoride affected the development of the brain and damaged the brain. Moreover, the results of the Y-maze test showed that fluoride increased the number of learning days, error reaction time, and total reaction time, and decreased the AchE activity in the brain (p < 0.05, p < 0.01), which indicated that fluoride reduced the learning and memory ability of the mice. Besides, the results showed that fluoride decreased the mRNA and protein expression levels of α4ß2 nAChRs and α7 nAChRs in the hippocampus and cortex (p < 0.05, p < 0.01). However, perinatal choline supplementation reversed the aforementioned fluoride-induced changes. In short, these results demonstrated that choline alleviated perinatal fluoride-induced learning and memory impairment, which will provide a rationale for the mitigation and prevention of fluoride-induced brain damage.

Research progress on the modulation mechanism of electroacupuncture for learning and memory impairment after ischemic stroke / 中国针灸

Electroacupuncture may play a role in treatment of learning and memory impairment after ischemic stroke by regulating phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt) signaling pathway, cyclic adenosine monophosphate (cAMP)-dependent protein kinase A (PKA)/cAMP response element binding protein (CREB) signaling pathway, nerve growth factor (NGF)/tyrosine kinase-A (TrkA) signaling pathway, Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway, Notch signaling pathway, erythropoietin-producing hepatocyte (Eph)/ephrin signaling pathway. The interactions among these pathways should be further explored in treatment of learning and memory impairment after ischemic stroke.

Effect of traditional Chinese medicine Syngnathus on D-galactose-induced learning and memory impairment in aging mice / 药学实践杂志

Objective To study the effect of traditional Chinese medicine, Syngnathus on learning and memory impairment induced by D-galactose in aging mice and its mechanism of action. Methods HPLC was used to determine the content of DHA, the active ingredient in anti-learning and memory impairment in Syngnathus. The aging mouse model was prepared by intraperitoneal injection of D-galactose (D-gal). Morris water maze test and Western blot were used to detect the ability of learning and memory, biochemical indicators and protein expression related to oxidative damage in the hippocampus, and to explore the protective effect and mechanism of Syngnathus on learning and memory impairment in aging mice. Results HPLC results showed that the DHA content in Syngnathus was 7.761 3 mg/g (calculated as crude drug), accounting for about 47% of the total composition. Morris water maze results showed that Syngnathus could reduce the escape latency of learning and memory-impaired aging mice and increase the target quadrant swimming time, the proportion of swimming distance and the number of times of crossing the platform, and improve the learning and memory impairment of mice. In addition, Syngnathus can activate the AKT/FOXO1/SOD2 signaling pathway in the hippocampus of aging mice with learning and memory impairment, promote the expression of oxidative stress pathway-related proteins, and improve the learning and memory impairment in aging mice by reducing the degree of oxidative damage in the hippocampus of aging mice. Conclusion This study found that Syngnathus is rich in DHA, which has the effect of improving learning and memory impairment induced by D-galactose in aging mice, and preliminarily clarified that its mechanism of action is related to anti-oxidation. Experimental evidence is provided.

Effects and mechanism of the ethanol extract of Tiarella polyphylla on learning and memory impairment in mice / 中国药房

OBJECTIV E To investigate the effect s and mechanism of the ethanol extract of Tiarella polyphylla （“TPE”）on learning and memory impairment in mice. METHODS Male Kunming mice were randomly divided into normal group ，model group，positive group （donepezil hydrochloride 4 mg/kg）and TPE low-dose ，medium-dose and high-dose groups （150，300，600 mg/kg），with 10 mice in each group. Drug administration groups were given relevant medicine intragastrically once a day ，and normal group and model group were given water intragastrically once a day ，for consecutive 22 d. On the 17th day ，administration groups and model group were intraperitoneally injected with scopolamine hydrobromide （3 mg/kg）to establish a model of learning and memory impairment. The learning and memory ability of the mice were evaluated by the Morris water maze. Hematoxylin-eosin （HE） staining was used for morphological observation of hippocampus cells of the mice. The levels of acetylcholinesterase （AChE），choline acetyltransferase （ChAT），superoxide dismutase （SOD），malondialdehyde（MDA），interleukin-6（IL-6）and tumor necrosis factor-α（TNF-α）in cerebral tissue as well as the relative expression of phosphorylated Tau protein （p-Tau），β-site amyloid precursor protein cleaving enzyme 1（BACE1）and amyloid precursor protein （APP）in hippocampus tissue were all detected. RESULTS The escape latency of mice in positive group ，TPE medium-dose and high-dose groups were all significantly shortened than the model group on the 4th to 5th day of training ，while the times of crossing platform and the percentage of movement distance in target quadrant were significantly increased （P＜0.05）. Compared with model group ，the neurons in the hippocampal CA 1 region of mice were increased to var ying degrees in administration groups ，the ne urons in solidified and atrophic state decreased ，and the arrangement of neurons tended to be close；the levels of ChAT and SOD in cerebral tissue were significantly increased in positive group and TPE medium-dose and high-dose groups ；the levels of AChE ，MDA，IL-6，the levels of TNF-α and relative expression of p-Tau ，BACE1 and APP in hippocampus tissue were decreased significantly （P＜ 0.05）. CONCLUSIONS TPE can improve the learning and memory impairment induced by scopolamine in mice ，and the mechanism may be related to balancing the brain cholinergic system ，alleviating oxidative stress injury ，improving inflammatory response，and inhibiting the overexpression of p-Tau ，BACE1 and APP .

Inhalation Administration of Agarwood Incense Rescues Scopolamine-Induced Learning and Memory Impairment in Mice.

Background: Agarwood, a type of herbal medicine widely used in Asian countries, is noted in traditional medicine for its intelligence-enhancing effects. Agarwood incense is traditionally administered by oral and nasal inhalation. To verify whether agarwood incense can exert its intelligence-enhancing effects in this way to rescue learning and memory impairment, typical clinical manifestations of dementia, we conducted a set of behavioral tests related to learning and memory. Methods: C57BL/6 mice were divided into six groups. In addition to the control and model groups, we added a donepezil treatment group to evaluate the effect of three different agarwood administration doses. After a week of administration, scopolamine was injected 30 min before each behavioral test to create a learning and memory impairment model. A series of behavioral tests [the Morris water maze test (MWM), the novel object recognition test (NOR), and the step-down test (SDT)] were used to assess their learning ability, as well as their spatial and recognition memory. Results: After scopolamine injection, the model group showed significant learning and memory impairment (i.e., longer latencies, lower crossing times, and lesser distance travelled in the target quadrant in MWM; a lower recognition index in NOR; and longer latencies and higher error times in SDT). The other four treatment groups all showed improvements in these indicators, and the overall therapeutic effect of agarwood was superior. Conclusion: The inhalation administration of agarwood can significantly improve the learning and memory impairment caused by scopolamine in mice, and the therapeutic effect varied between doses.

Effect of Ultrafine Powder of Gastrodiae Rhizoma in Improving Learning and Memory Ability of Vascular Dementia Rats by Regulating Cholinergic System / 中国实验方剂学杂志

Objective:To investigate whether ultrafine powder of Gastrodiae Rhizoma （UPG） can alleviate the learning and memory impairment of vascular dementia rats and delay the process of VD， and whether this effect is related to the release of acetylcholine （Ach） through the regulation with acetylcholinesterase （AChE） and choline acetyltransferase （ChAT） and control of cholinergic system. Method:SD rats were randomly divided into sham operation group， UPG low dose group （0.45 g·kg-1）， UPG high dose group （1.8 g·kg-1） and Huperzine A group （80 μg·kg-1）， with 12 rats in each group. The drug administration groups were given orally drugs once a day for 8 weeks， and sham group and model group were given orally the same amount of distilled water. The learning and memory ability of the rats with VD were evaluated by the Morris water maze. Htoxylin eosin（HE） staining was used for pathomorphological observation of hippocampus CA1 area of the rats. The content of Ach was determined by enzyme-linked immunosorbent assay（ELISA）， AChE and ChAT protein expressions were detected by Western blot， and expression of ChAT in hippocampus CA1 area was observed by immunohistochemistry. Result:Compared with the sham operation group， the escape latency of the model group was significantly increased （P<0.01）， and the frequency of crossings platform and the time of staying in the target quadrant were reduced significantly （P<0.01）. HE staining of hippocampal tissues from VD rat showed neuron disorders， loss and degeneration and necrosis， pyknosis of the nucleus and light coloration of the cytoplasm. The level of acetylcholine in the hippocampus was significantly decreased by ELISA （P<0.05）， the expression level of AChE protein was significantly up-regulated， and the expression level of ChAT protein was significantly down-regulated （P<0.01）. Compared with model group， each administration group could significantly reduce the escape latency of the model rats， and significantly increase the frequency of crossing platform and the time of staying in the target quadrant （P<0.01）， the content of Ach was significantly increased （P<0.05）， the expression of AChE protein was significantly down-regulated （P<0.01）， while the expression of ChAT protein was significantly up-regulated （P<0.01）. Conclusion:UPG improves the learning and memory ability of vascular dementia rats， and its mechanism may be related to the increase of Ach， ChAT level and the decrease of AChE level.

Protective effects of tetrahydropalmatine against ketamine-induced learning and memory injury via antioxidative, anti-inflammatory and anti-apoptotic mechanisms in mice.

Tetrahydropalmatine exerts numerous pharmacological activities, including analgesic and narcotic effects; anti-arrhythmic, blood pressure lowering and cardioprotective effects; protective effects against cerebral ischemia-reperfusion injury; inhibition of platelet aggregation; prevention of ulcerative diseases and inhibition of gastric acid secretion; antitumor effects; and beneficial effects on the withdrawal symptoms associated with drug addiction. The present study aimed to investigate the protective effects of tetrahydropalmatine against ketamine­induced learning and memory impairment in mice. The Morris water maze test and open field test were used to analyzed learning and memory impairment in mice. ELISA kits and western blotting were used to analyze oxidative stress, inflammation factors, caspease­3 and caspase­9, iNOS, glial fibrillary acidic protein (GFAP), glial cell­derived neurotrophic factor (GDNF), cytochrome c and phospholipase C (PLC)­Î³1 protein expression. The results demonstrated that tetrahydropalmatine treatment significantly decreased escape latency in the learning phase and increased the number of platform site crossings in ketamine­induced mice. In addition, tetrahydropalmatine significantly inhibited oxidative stress, inflammation and acetylcholinesterase activity, and decreased acetylcholine levels in ketamine­induced mice. Tetrahydropalmatine also suppressed iNOS protein expression, weakened caspase­3 and caspase­9 activation, inhibited nuclear factor­κB, glial fibrillary acidic protein, cytochrome c and phospholipase C­Î³1 protein expression, and induced glial cell­derived neurotrophic factor protein expression in ketamine­induced mice. Taken together, these results indicated that tetrahydropalmatine may protect against ketamine­induced learning and memory impairment in mice via antioxidative, anti­inflammatory and anti­apoptotic mechanisms. The present study provided an experimental basis for the clinical application of tetrahydropalmatine to reduce the severe side effects associated with ketamine therapy in future studies.

Electroacupuncture ameliorates spatial learning and memory impairment via attenuating NOX2-related oxidative stress in a rat model of Alzheimer's disease induced by Aß1-42.

Alzheimer's disease (AD) is a chronic neurodegenerative disorder characterized by progressive deterioration of cognition and memory, in which oxidative stress has been played a crucial role in the pathology of AD. Electroacupuncture (EA) is a widely used therapy based on traditional acupuncture combined with modern electrotherapy in Asia. The present study aimed to determine the effects of EA treatment on spatial learning and memory impairment, and to elucidate the status of NOX2-related oxidative stress in a rat model of Alzheimer's disease induced by Beta-amyloid1-42 (Aß1-42). Fifty-six adult female Sprague-Dawley (SD) rats were randomly divided into four groups: sham, sham+EA, AD and AD+EA. The rats in Sham+EA and AD+EA groups were respectively administrated EA treatment at Baihui and yongquan acupoints, once a day for 30 min, lasting for 28 days. The spatial learning and memory functions were assessed by Morris water maze (MWM) test. The activities of total antioxidant capacity (T-AOC), reactive oxygen species (ROS), malondialdehyde (MDA) and 8-hydroxy-2-deoxyguanosine (8-OH-dG) were evaluated. Moreover, the neuronal injury was detected by Nissl staining. Meanwhile, the NeuN expression was examined in the hippocampus, the expression levels of Nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase2(NOX2) was detected by immunofluorescence staining and western blot. The results showed that EA treatment significantly improved spatial learning and memory impairment in rats induced by Aß1-42. Concomitantly, EA treatment markedly restored T-AOC and attenuated the abnormal increase in levels of ROS, MDA and 8-OH-dG in the hippocampus of the AD rats. More notably, EA treatment also effectively ameliorated neuronal injury and counteracted the aberrant increase of NOX2 levels in the hippocampus of AD rats. Our findings suggested that EA is a potential strategy for the treatment of AD, and the possible mechanism is associated with the alleviation of neuronal injury and inhibition of NOX2-related oxidative stress.

Tangzhining exhibits a protective effect against cognitive dysfunction in diabetic rats.

Previous studies have suggested that diabetes significantly impairs the cognitive function. Tangzhining (TZN), as a kind of Traditional Chinese Medicine (TCM), has been widely used to treat diabetes in China. However, the effect of TZN on treatment of diabetes-induced learning and memory deficits has not been well documented. The present study was to investigate the effect of TZN on diabetes-induced learning and memory deficits and delineate the underlying molecular mechanism. Diabetic rats were randomly grouped and treated with various doses of TZN (0.47, 0.94 and 1.4 g/kg) by intraperitoneal injection. Using the Morris water maze, TZN treatment (0.94 g/kg and 1.4 g/kg) reduced markedly the escape latency and path length of diabetic rats. The morphological changes of pyramidal cells in hippocampus of diabetic rats were apparently reversed and improved by TZN treatment, in comparison with that in diabetic rats without TZN treatment. Moreover, the results of Western blot analysis showed that TZN treatment significantly increased the protein expression of glutamic acid decarboxylase (GAD) and excitatory amino acid carrier 1 (EAAC1) in hippocampus of diabetic rats. Furthermore, TZN treatment increased the protein expression of N-methyl-D-aspartic acid (NMDA) receptor subunits including NR1 and NR2B. Taken together, our data suggest that TZN sustains the balance between glutamate (Glu) and GABA by regulating GAD and EAAC1, and maintains the NMDA receptors activity for learning and memory function through regulating the subunits NR1 and NR2B.

Neuroprotection and mechanisms of atractylenolide III in preventing learning and memory impairment induced by chronic high-dose homocysteine administration in rats.

Studies demonstrated that chronic high-dose homocysteine administration induced learning and memory impairment in animals. Atractylenolide III (Aen-III), a neuroprotective constituent of Atractylodis macrocephalae Koidz, was isolated in our previous study. In this study, we investigated potential benefits of Aen-III in preventing learning and memory impairment following chronic high-dose homocysteine administration in rats. Results showed that administration of Aen-III significantly ameliorated learning and memory impairment induced by chronic high-dose homocysteine administration in rats, decreased homocysteine-induced reactive oxygen species (ROS) formation and restored homocysteine-induced decrease of phosphorylated protein kinase C expression level. Moreover, Aen-III protected primary cultured neurons from apoptotic death induced by homocysteine treatment. This study provides the first evidence for the neuroprotective effect of Aen-III in preventing learning and impairment induced by chronic administration of homocysteine. Aen-III may have therapeutic potential in treating homocysteine-mediated cognitive impairment and neuronal injury.