Alzheimer's disease (AD) is one of the major neurodegenerative disorders of the elderly, which is characterized by the accumulation and deposition of amyloid-beta (Aβ) peptide in human brains. Oxidative stress and neuroinflammation induced by Aβ in brain are increasingly considered to be responsible for the pathogenesis of AD. The present study aimed to determine the protective effects of walnut peptides against the neurotoxicity induced by Aβ25-35 in vivo. Briefly, the AD model was induced by injecting Aβ25-35 into bilateral hippocampi of mice. The animals were treated with distilled water or walnut peptides (200, 400 and 800 mg/kg, p.o.) for five consecutive weeks. Spatial learning and memory abilities of mice were investigated by Morris water maze test and step-down avoidance test. To further explore the underlying mechanisms of the neuroprotectivity of walnut peptides, the activities of superoxide dismutase (SOD), glutathione (GSH), acetylcholine esterase (AChE), and the content of malondialdehyde (MDA) as well as the level of nitric oxide (NO) in the hippocampus of mice were measured by spectrophotometric method. In addition, the levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β) and IL-6 in the samples were determined using ELISA. The hippocampal expressions of inducible nitric oxide synthase (iNOS) and nuclear factor κB (NF-κB) were evaluated by Western blot analysis. The results showed that walnut peptides supplementation effectively ameliorated the cognitive deficits and memory impairment of mice. Meanwhile, our study also revealed effective restoration of levels of antioxidant enzymes as well as inflammatory mediators with supplementation of walnut peptides (400 or 800 mg/kg). All the above findings suggested that walnut peptides may have a protective effect on AD by reducing inflammatory responses and modulating antioxidant system.
Acetylcholinesterase ; metabolism ; Alzheimer Disease ; drug therapy ; etiology ; Amyloid beta-Peptides ; toxicity ; Animals ; Female ; Glutathione ; metabolism ; Hippocampus ; drug effects ; metabolism ; Interleukins ; metabolism ; Juglans ; chemistry ; Male ; Malondialdehyde ; metabolism ; Maze Learning ; Memory Disorders ; drug therapy ; etiology ; Mice ; NF-kappa B ; metabolism ; Neuroprotective Agents ; pharmacology ; therapeutic use ; Nitric Oxide ; metabolism ; Peptide Fragments ; toxicity ; Peptides ; pharmacology ; therapeutic use ; Plant Extracts ; pharmacology ; therapeutic use ; Superoxide Dismutase ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism

Tongluo Xingnao effervescent tablet (TLXNET) is a patented prescription, which comes from modified Xionggui decoction and can improve cognitive function. However, its effect on the urine metabolites and anti-dementia mechanism in the dementia model rats induced by hippocampal injection with Aβ25-35 remains unclear. The experiment focused on the changes in trajectory and inter-relationship among the urinary metabolite of rats in the blank group, Aβ25-35 hippocampal injection dementia model group and the TLXNET intervention group, in order to determine theirs characteristic metabolic markers and explain the anti-dementia effect of TLX-NET base on the change of metabolic trajectory of these bio-markers. According to the experimental results, 5, 6-indolequinone, 4-hydroxyphenyl pyruvic acid (4-HPPA), cortisol and 3-thiosulfate lactic were preliminarily identified as the characteristic metabolic markers. They mainly participate in dopamine system, glucocorticoids and energy metabolic pathways. TLXNET can apparently downregulate the disturbances of metabolic trajectory of the four bio-markers. The experiment indicates that the dementia model induced by injecting Aβ25-3 into hippocampus has its characteristic endogenous metabolic markers in urine, and ELXNET can ameliorate dementia by down-regulating the disturbances of metabolic trajectory.
Amyloid beta-Peptides ; metabolism ; toxicity ; Animals ; Biomarkers ; urine ; Dementia ; drug therapy ; urine ; Drugs, Chinese Herbal ; administration & dosage ; Female ; Hippocampus ; drug effects ; metabolism ; Humans ; Male ; Metabolomics ; Peptide Fragments ; metabolism ; toxicity ; Rats ; Rats, Sprague-Dawley ; Tablets ; administration & dosage ; Urine ; chemistry

BACKGROUNDThe advent of brain stimulation techniques to treat movement disorders and psychiatric diseases has shown potential to decode the neural mechanism that underlies the cognitive process by modulating the interrupted circuit. Here, the present investigation aimed at evaluating the influence of deep brain stimulation of the anterior nucleus thalamus (ANT-DBS) on memory.

METHODSThirty-two rats were randomized into phosphate buffer saline (PBS) group (n = 8, rats received PBS injections without implantation of electrodes into the ANT), Alzheimer's dementia (AD) group (n = 8, rats received Aβ1-40 injections without implantation of electrodes into the ANT), ANT sham stimulation group (n = 8, rats received Aβ1-40 injections with implantation of electrodes into the ANT but without stimulation) and ANT stimulation group (n = 8, rats received Aβ1-40 injections with implantation of electrodes into the ANT and stimulation). A Morris maze test was used for determining the effect of electrical stimulation on cognitive function in rats. The data were assessed statistically with one-way analysis of variance (ANOVA) followed by Tukey's tests for multiple post hoc comparisons.

RESULTSThe data showed that in the training test, PBS group and AD group managed to learn the hidden-platform faster and faster while AD group needed a significantly longer time to reach the platform than PBS group (P < 0.05). Meanwhile, ANT stimulation group demonstrated a significantly shorter time to reach the platform (P < 0.05) compared to the AD group, while there was no significant difference between the ANT sham stimulation group and the AD group (P > 0.05). On the probe test, the AD group spent less time ((10.15 ± 2.34) seconds) in the target quadrant than the PBS group ((28.20 ± 2.75) seconds) (P < 0.05). And the times of platform-traversing of the AD group (3.35 ± 1.12) significantly decreased compared with the PBS group (8.69 ± 2.87) (P < 0.05). However, the times of platform-traversing and the time spent in the target quadrant of the ANT stimulation group significantly increased compared to the AD group (P < 0.05), while times of platform-traversing or the time spent in the target quadrant was not significantly different between the ANT sham stimulation group and the AD group (P > 0.05).

CONCLUSIONBilateral high-frequency stimulation of the ANT may be useful as a potential therapeutic modality for cognitive dysfunction in AD.

Amyloid beta-Peptides ; administration & dosage ; toxicity ; Animals ; Anterior Thalamic Nuclei ; drug effects ; Cognition ; drug effects ; Cognition Disorders ; chemically induced ; therapy ; Deep Brain Stimulation ; methods ; Hippocampus ; drug effects ; Male ; Peptide Fragments ; administration & dosage ; toxicity ; Rats ; Rats, Sprague-Dawley

UNLABELLEDOBJECTIVE To study the in vitro effect and mechanism of Ginkgo biloba Extract 50 (GBE50) for inhibiting beta-amyloid (Abeta)-induced oxidative stress in rats' hippocampal neurons.

METHODSThe primary hippocampal neurons were cultured in vitro and divided into 4 groups, i. e. the normal control group (Ctrl), the Abeta group, the propanediol control group (PDO), and the six GBE50 concentrations groups (5, 10, 25, 50, 100, and 200 microg/mL). Excepted the Ctrl group, neurons were induced to oxidative stress by 20 gmolLAbeta25-35. The MTT and fluorescent probes labeling were used to observe the effect of GBE50 with different concentrations on the cell viability and the generation of intracellular reactive oxygen species (ROS) in neurons. Furthermore, Western blot was used to detect the cytoplasmic/total cytochrome C (Cyto C) ratio and total intracytoplasmal Cyto C, and the effect of the expression of oxidative stress-related protein Cyto C and activated Caspase-3 in three GBE50 concentrations groups (25, 50, and 100 microg/mL).

RESULTSCompared with the Ctrl group, the cell vitality was obviously lowered and intracellular ROS generation significantly increased after induction of 20 micromol/L Abeta25-35 (both P < 0.05). Compared with the Abeta group, the cell vitality was evidently improved after treated with different GBE50 doses. Except for 10 microg/mL, the cell vitality could be obviously elevated along with increased drug concentrations (P < 0.05). Meanwhile, the intracellular ROS generation decreased significantly in each GBE50 dose groups (P < 0.05). Abeta could increase the cytoplasmic/total Cyto C ratio and enhance the activated Caspase-3 expression significantly (P < 0.05). Compared with the Abeta group, among the three concentrations of GBE50, the Cyto C ratio was obviously lowered in the 100 microg/mL GBE50 group (P < 0.05), and the expression of activated Caspase-3 significantly decreased in 50 microg/mL and 100 microg/mL GBE50 groups (P < 0.05).

CONCLUSIONS20 micromol/L Abeta25-35 could induce the generation of intracellular ROS in hippocampal neurons. GBE50 could inhibit Abeta induced intracellular oxidative stress of neurons through lowering the cytoplasmic/total Cyto C ratio and inhibiting the activation of apoptosis protein Caspase-3 expression.

Amyloid beta-Peptides ; toxicity ; Animals ; Cells, Cultured ; Cytochromes c ; metabolism ; Hippocampus ; metabolism ; Neurons ; drug effects ; metabolism ; Oxidative Stress ; drug effects ; Peptide Fragments ; toxicity ; Plant Extracts ; pharmacology ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo study the role of PI3K/Akt pathway in the neuroprotective effect of paeoniflorin on PC12 cells.

METHODThe paeoniflorin group (5, 10, 20 μmol · L(-1)) was pretreated for 30 min, and then added with Aβ25-35 (20 μmol · L(-1)) for interaction for 24 h. Inhibitor LY294002 (10 μmol · L(-1)) was pretreated for 30 min before the action of paeoniflorin (10 μmol · L(-1)). The MTT colorimetric method was used to detect the cell viability. The apoptosis rate was tested by the FITC-Annexin V/PI staining. The protein expression of p-AKT, Bax, Bcl-2 and cleaved caspase-3 protein were detected by Western blot analysis.

RESULTPaeoniflorin could significantly inhibit the Aβ25-35-induced PC12 cell toxicity and apoptosis. Its protection effect may be achieved by up- regulating AKT phosphorylation level, increasing Bcl-2 protein expression, reducing Bax protein expression, inhibiting the activation of caspase-3. Inhibitor LY294002 could weaken the above protective effects of paeoniflorin.

CONCLUSIONPaeoniflorin could activate PI3K/Akt signaling pathway to protect the PC12 cell injury induced by Aβ25-35.

Alzheimer Disease ; drug therapy ; genetics ; metabolism ; physiopathology ; Amyloid beta-Peptides ; toxicity ; Animals ; Apoptosis ; drug effects ; Cell Survival ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Glucosides ; pharmacology ; Humans ; Monoterpenes ; pharmacology ; Neurons ; cytology ; drug effects ; metabolism ; Neuroprotective Agents ; pharmacology ; PC12 Cells ; Peptide Fragments ; toxicity ; Phosphatidylinositol 3-Kinases ; genetics ; metabolism ; Proto-Oncogene Proteins c-akt ; genetics ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; Rats ; Signal Transduction ; drug effects

OBJECTIVETo investigate the effect of berberine on expressions of tumor necrosis factor alpha (TNF-alpha) and receptor type I (TNFR1) in Abeta25-35-induced inflammatory reaction in SH-SYSY cell lines.

METHODThe 5 micromol . L-1 Abeta25-35 was used to treat SH-SY5Y cells for 24 hours, in order to establish the Alzheimer's disease (AD) model. Before modeling, berberine was given for pretreatment for 2 hours. The experiment included the normal control group, the AD model group, and indometacin low dose and high dose groups. Spectrophotometry was adopted to detect the activity of LDH. Meanwhile, the level of TNF-alpha was determined by ELISA, and the expression of TNFR1 genes was detected by RT-PCR.

RESULTCompared with the normal control group, the AD cell model group showed significant increase in LDH, TNF-alpha, and TNFR1 gene and protein expressions in the culture media. After intervention with berberine, the activity of LDH and TNF-alpha reduced in cell supernatant. The intervention with berberine could down-regulate TNFR1 gene and protein expressions, particularly 1, 10 x 10(-6) mol . L-l berberine showed a more notable effect in regulating TNFR1.

CONCLUSIONBerberine has the protective effect in Abeta-induced inflammatory injury in SH-SY5Y cells. Its mechanism may be related to the expression of its anti inflammatory factor TNF-alpha and its type I receptor TNFR1. Specifically, its regulation to TNFR1 shows dose dependence.

Amyloid beta-Peptides ; toxicity ; Berberine ; pharmacology ; Cell Line ; Humans ; Inflammation ; chemically induced ; metabolism ; Peptide Fragments ; toxicity ; Receptors, Interleukin-1 Type I ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo investigate the neuroprotective effects and mechanism of paeoniflorin on Abeta25-35-induced oxidative stress in PC12 cells.

METHODThe proliferation of induced PC12 cells were investigated by the MTT method. The leakage rate of lactate dehydrogenase (LDH), the intracellular content of malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were also measured. The changes of the intracellular reactive oxygen species (ROS) level and the mitochondrial membrane potential (MMP) were investigated by flow cytometry using DCFH-DA and Rh123 staining. The protein expression of HO-1, Cyt C and cleaved Caspase-3 was detected by Western blot.

RESULTThe results showed that paeoniflorin at different doses (5, 10, 20 micromol . L-1) could increase the cell viability and activities of antioxidant enzyme (GSH-Px, SOD and HO-1), prevent LDH release and lipid peroxidation (MDA) production, decrease the level of intracellular ROS, increase MMP, inhibit the release of cytochrome c from the mitochondria and attenuate activation of Caspase-3.

CONCLUSIONPaeoniflorin can protect PC12 cells from Abeta25-35 oxidative stress injuries. The mechanism may be related to its antioxidant action and inhibition of mitochondria-mediated caspase signaling pathways.

Amyloid beta-Peptides ; toxicity ; Animals ; Antioxidants ; metabolism ; Benzoates ; pharmacology ; Bridged-Ring Compounds ; pharmacology ; Caspase 3 ; metabolism ; Glucosides ; pharmacology ; Glutathione Peroxidase ; metabolism ; Lipid Peroxidation ; drug effects ; Malondialdehyde ; metabolism ; Monoterpenes ; Oxidative Stress ; drug effects ; PC12 Cells ; Peptide Fragments ; toxicity ; Rats ; Reactive Oxygen Species ; metabolism ; Superoxide Dismutase ; metabolism

OBJECTIVETo observe the effect of oligosaccharides of Morinda officinalis (OMO) on beta-amyloid-induced dementia rats, and study its pharmacological mechanism in treatment of dementia.

METHODThe dementia model rats were established by injecting Abeta25-35 10 microLg into bilateral hippocampus. OMO high-dose (60 mg . kg-1 . d-1) group, OMO low-dose (20 mg . kg-1 . d-1 ) groups, the blank group, the sham operation group and the positive donepezil HC1 group (0. 125 mg kg-1 . d-1) were designed for the experiment. They were continuously administered with drugs at the 15th day after operation for 25 days. Kit microplate method was used to detect the contents of super oxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT), glutathione reductase (GSH-Px), acetylcholine (ACh) , acetylcholinesterase (AChE) and Na+ /K+ -ATPase.

RESULTCompared with the model group, all of administration groups showed higher SOD, CAT and GSH-Px levels, and lower MDA in the brain tissues. Besides, they also showed rise in the activities of ACh and Na+ /K+ -ATPase.

CONCLUSIONOMO can ameliorate on beta-amyloid-induced dementia rats by enhancing oxidation resistance, activating brain energy metabolism and improving the injury of cholinergic system.

Acetylcholinesterase ; metabolism ; Amyloid beta-Peptides ; toxicity ; Animals ; Catalase ; metabolism ; Dementia ; chemically induced ; drug therapy ; Glutathione Peroxidase ; metabolism ; Glutathione Reductase ; metabolism ; Male ; Malondialdehyde ; metabolism ; Morinda ; chemistry ; Neuroprotective Agents ; metabolism ; Oligosaccharides ; therapeutic use ; Oxidative Stress ; drug effects ; Peptide Fragments ; toxicity ; Rats ; Superoxide Dismutase ; metabolism

OBJECTIVETo assess the neuroprotective effects of ginsenoside Rg1 against β-amyloid peptide (Aβ(25-35))-induced apoptosis in primarily cultured rat cortical neurons.

METHODSPrimarily cultured cortical neurons were obtained from embryonic (E18d) rat fetus and maintained in neurobasal medium for 7d. Primary neurons pretreated with 1 μmol/L, 10 μmol/L or 20 μmol/L Rg1 for 24 h were challenged with 10 μmol/L Aβ(25-35) for 72 h. Morphological changes of neurons were evaluated; mitochondrial membrane potential (ΔΨm) was measured; with JC-1 staining and the expression of neural apoptosis-related proteins was detected by Western blot analysis.

RESULTSExposure to Aβ(25-35) for 72 h caused serious neural cell insults. A pretreatment with Rg1 significantly reduced Aβ(25-35)induced cell death in a dose-dependent manner, with a maximal effect (-90%) obtained at 20 μmol/L. The JC-1 staining results demonstrated the loss of ΔΨm after Aβ(25-35) treatment, while Rg1 maintained the normal level of ΔΨm. A series of mitochondrion-mediated apoptotic events happened after Aβ(25-35) treatment, such as decrease of Bcl-2/Bax, release of cytochrome C and activation of caspase 9 and caspase 3, which were all blocked by Rg1 pretreatment. Both estrogen receptor (ER) antagonist ICI182, 780 and glucocorticoid receptor (GR) antagonist RU486 blocked the antiapoptotic effects of Rg1.

CONCLUSIONGinsenoside Rg1 protects primary cultured rat cortical neurons from Aβ(25-35)-induced injury, which may be associated with mitochondrion-mediated antiapoptosis pathway.

Amyloid beta-Peptides ; toxicity ; Animals ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Caspase 9 ; metabolism ; Cells, Cultured ; Cerebral Cortex ; drug effects ; metabolism ; pathology ; Ginsenosides ; pharmacology ; Membrane Potential, Mitochondrial ; drug effects ; Mitochondria ; drug effects ; metabolism ; physiology ; Neurons ; drug effects ; metabolism ; pathology ; Peptide Fragments ; toxicity ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rats ; Rats, Sprague-Dawley ; bcl-2-Associated X Protein ; metabolism

OBJECTIVETo investigate the protective effect of paeonol on amyloid beta1-42 (Abeta1-42)-induced neurotoxicity and its mechanism.

METHODHippocampal neurons of well-grown newborn SD rats and differentiated SH-SY5Y cell lines were cultured with various concentrations of paeonol (1, 5, 10 micromol x L(-1), respectively) for 6 hours and then incubated with Abeta1-42 oligomer (30 micromol x L(-1)) for 24 hours and 48 hours, respectively. The neuron apoptosis was observed by Heochst33258. Annexin V/PI double stain flow cytometry assay was adopted for determining SH-SY5Y cell apoptosis rate. And the expression of BDNF and Bcl-2 mRNA was detected by RT-PCR.

RESULTCompared with the model group, various concentrations of paeonol (1, 5, 10 micromol x L(-1)) significantly reduced the hippocampal neurons karyopycnosis, decreased the rate of SH-SY5Y cell apoptosis to 22.4%, 18.1% and 16.4%, respectively, and improved the expressions of BDNF and Bcl-2 mRNA.

CONCLUSIONPaeonol relieves Abeta1-42 oligomer-induced neuron injury by increasing BDNF and Bcl-2 expressions.

Acetophenones ; pharmacology ; Alzheimer Disease ; drug therapy ; genetics ; metabolism ; physiopathology ; Amyloid beta-Peptides ; toxicity ; Animals ; Apoptosis ; drug effects ; Cell Line ; Cells, Cultured ; Hippocampus ; cytology ; drug effects ; Humans ; Neurons ; drug effects ; Neuroprotective Agents ; pharmacology ; Peptide Fragments ; toxicity ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley