Yizhijiannao Granule and a combination of its effective monomers,icariin and Panax notoginseng saponins,inhibit early PC12 cell apoptosis induced by beta-amyloid(25-35)

One of our previous studies showed that Yizhijiannao Granule,a compound Chinese medicine, effectively improved the clinical symptoms of Alzheimer’s disease.In the present study,we established a model of Alzheimer’s disease using beta-amyloid（25-35）in PC12 cells,and treated the cells with Yizhijiannao Granule and its four monomers,i.e.,icariin,catechin,Panax notoginseng saponins,and eleutheroside E.Flow cytometry showed that Yizhijiannao Granule-containing serum, icariin,Panax notoginseng saponins,and icariin＋Panax notoginseng saponins were protective against beta-amyloid（25-35）-induced injury in PC12 cells.Icariin in combination with Panax notoginseng saponins significantly inhibited early apoptosis of PC12 cells with beta-amyloid （25-35）-induced injury compared to icariin or Panax notoginseng saponins alone.The effects of icariin＋Panax notoginseng saponins were similar to the effects of Yizhijiannao Granule.The findings indicate that two of the effective monomers of Yizhijiannao Granule,icariin and Panax notoginseng saponins,can synergistically inhibit early apoptosis of PC12 cells induced by beta-amyloid（25-35）.

Neuroprotective effects of human telomerase reverse transcriptase on beta-amyloid fragment 25-35-treated human embryonic cortical neurons

BACKGROUND： Numerous current studies have suggested that human telomerase reverse transcriptase （hTERT） gene has neuroprotective effects and can inhibit apoptosis induced by various cytotoxic stresses; however, the mechanism of action remains unknown. OBJECTIVE： To evaluate the neuroprotective effects and possible mechanism of action of hTERT gene transfection in human embryonic cortical neurons treated with beta-amyloid fragment 25-35 （AI325-35）. DESIGN, TIME AND SETTING： The randomized, controlled and molecular biological studies were performed at the Department of Anatomy and Brain Research, Zhongshan School of Medicine, Sun Yat-sen University, China, from September 2005 to June 2008. MATERIALS： AdEasy-1 Expression System was gifted by Professor Guoquan Gao from Sun Yat-Sen University, China. Human cortical neurons were derived from 12-20 week old aborted fetuses, obtained from the Guangzhou Maternal and Child Health Hospital, China. Mouse anti-Odk5 and mouse anti-p16 monoclonal antibodies （Lab Vision, USA）, and mouse anti-hTERT monoclonal antibody （Epitomics, USA）, were used in this study. METHODS： （1） Recombinant adenovirus vectors, encoding hTERT （Ad-hTERT） and green fluorescent protein （Ad-GFP）, were constructed using the AdEasy-1 Expression System. Human embryonic cortical neurons in the Ad-hTERT group were transfected with Ad-hTERT for 1-21 days. Likewise, human embryonic cortical neurons in the Ad-GFP group were transfected with Ad-GFP for 1-21 days. Human embryonic cortical neurons in the control group were cultured as normal. （2） Human embryonic cortical neurons in the Ad-hTERT group were treated with 10 pmol/L Aβ25-35 for 24 hours. Normal human embryonic cortical neurons treated with 10 pmol/Lβ25.35 for 24 hours served as a model group. Human embryonic cortical neurons in the Ad-GFP and control groups were not treated with Aβ25-35. MAIN OUTCOME MEASURES： Expression of hTERT in human embryonic cortical neurons was evaluated by immunocytochemical staining and Western blot assay. Telomerase activity was measured using a PCR-based telomeric repeat amplification protocol （TRAP） ELISA kit. Neural activity in human embryonic cortical neurons was examined by MTT assay; apoptosis was measured using TUNEL assay; and Cdk5 and p16 protein expressions were measured by Western blot. RESULTS： Expression of hTERT protein was significantly increased and peaked at day 3 post-transfection in the Ad-hTERT group. No hTERT expression was detected in the Ad-GFP and control groups. Telomerase activity was significantly greater in the Ad-hTERT group compared with the Ad-GFP and control groups （P 〈 0.01）. Compared with the control group, cell activity was significantly decreased （P 〈 0.05）, and cell apoptotic rate, Cdk5 and p16 expression were significantly increased （P 〈 0.01） in the model group. Compared with the model group, cell activity was increased in the Ad-hTERT group, and peaked at day 3 post-transfection （P 〈 0.05）. Neuroprotective effects also peaked at day 3 post-transfection; and the apoptotic rate, Cdk5 and p16 expression significantly decreased （P 〈 0.01）. CONCLUSION： Expression of hTERT in human embryonic cortical neurons can relieve Aβ25-35-induced neuronal apoptosis. The possible mechanism by which hTERT produces these neuroprotective effects may be associated with inhibition of Cdk5 and p16 expression.

Effects of L-3-n-butylphthalide on caspase-3 and nuclear factor kappa-B expression in primary basal forebrain and hippocampal cultures after beta-amyloid peptide 1-42 treatment

BACKGROUND： L-3-n-butylphthalide （L-NBP） can inhibit phosphorylation of tau protein and reduce the neurotoxicity of beta-amyloid peptide 1-42 （Aβ1-42）. OBJECTIVE： To observe the neuroprotective effects of L-NBP on caspase-3 and nuclear factor kappa-B （NF- K B） expression in a rat model of Alzheimer＇s disease. DESIGN, TIME AND SETTING： A cell experiment was performed at the Central Laboratory of Provincial Hospital affiliated to Shandong University between January 2008 and August 2008. MATERIALS： L-NBP （purity 〉 98%） was provided by Shijiazhuang Pharma Group NBP Pharmaceutical Company Limited. Aβ1-42, 3-[4,5-dimethylthiazolo-2]-2,5 iphenyltetrazolium bromide （MTT）, and rabbit anti-Caspase-3 polyclonal antibody were provided by Cell Signaling, USA; goat anti-choactase and rabbit anti-NF- kB antibodies were provided by Santa Cruz, USA. METHODS： Primary cultures were generated from rat basal forebrain and hippocampal neurons at 17 or 19 days of gestation. The cells were assigned into five groups： the control group, the Aβ1-42 group （2 μmol/L）, the Aβ1-42 ＋ 0.1 μmol/L L-NBP group, the Aβ1-42 ＋ 1 μ mol/L L-NBP group, and the Aβ1-42 ＋ 10μmol/L L-NBP group. The neurons were treated with Aβ1-42 （2 μmol/L） alone or in combination with L-NBP （0.1, 1, 10 μmol/L） for 48 hours. Cells in the control group were incubated in PBS. MAIN OUTCOME MEASURES： Morphologic changes were evaluated using inverted microscopy, viability using the M-I-I- method, and the changes in caspase-3 and NF- k B expression using Western blot. RESULTS： Induction with Aβ1-42 for 48 hours caused cell death and soma atrophy, and increased caspase-3 and NF- K B expression （P 〈 0.05）. L-NBP blocked these changes in cell morphology, decreased caspase-3 and NF- k B expression （P 〈 0.05）, and improved cell viability, especially at the high dose （P 〈 0.05）. CONCLUSION： AI3^-42 is toxic to basal forebrain and hippocampal primary neurons; L-NBP protects against this toxicity and inhibits the induction of caspase-3 and NF- K B expression.

Protective Effect of Ecdysterone on PC12Cells Cytotoxicity Induced by Beta-amyloid_(25-35)

Objective： To examine the protective effect of ecdysterone （ECR） against beta-amyloid peptide fragment25-35 （Aβ25-35）-induced PC12 cells cytotoxicity, and to further explore its mechanism. Methods： Experimental PC12 cells were divided into the Aβ group （treated by Aβ25-35 100μmol/L）, the blank group （untreated）, the positive control group （treated by Vit E 100 μmol/L after induction） and the ECR treated groups （treated by ECR with different concentrations of 1, 50 and 100 μmol/L）. The damaged and survival condition of PC12 cells in various groups was monitored by lactate dehydrogenase （LDH） release and MTT assay. The content of malondialdehyde （MDA） was measured by fluorometric assay to indicate the lipid peroxidation. And the antioxidant enzymes activities in PC12 cells, including superoxide dismutases（SOD）, catalase （CAT） and glutathione peroxidase（GSH-Px）, were detected respectively. Results： After PC12 cells were treated with Aβ25-35 （100 μmol/L） for 24 hrs, they revealed a great decrease in MTT absorbance and activity of antioxidant enzymes, including SOD, CAT and GSH-Px as well as a significant increase of LDH activity and MDA content in PC12 cells （P〈0.01）. When the cells was pretreated with 1-100 μmol/L ECR for 24 hrs before Aβ25-35 treatment, the above-mentioned cytotoxic effect of Aβ25-35 could be significantly attenuated dose-dependently, for ECR 50 μmol/L, P〈0.05 and for ECR 100 μmol/L, P〈0.01. Moreover, ECR also showed significant inhibition on the Aβ25-35 induced decrease of SOD and GSH-Px activity, but not on that of CAT. Conclusion： ECR could protect PC12 cells from cytotoxicity of Aβ25-35, and the protective mechanism might be related to the increase of SOD and GSH-Px activities and the decrease of MDA resulting from the ECR-pretreatment.

Overexpression of estrogen receptor beta alleviates the toxic effects of beta-amyloid protein on PC12 cells via non-hormonal ligands

After binding to the estrogen receptor, estrogen can alleviate the toxic effects of beta-amyloid protein, and thereby exert a therapeutic effect on Alzheimer＇s disease patients. Estrogen can increase the incidence of breast carcinoma and endometrial cancer in post-menopausal women, so it is not suitable for clinical treatment of Alzheimer＇s disease. There is recent evidence that the estrogen receptor can exert its neuroprotective effects without estrogen dependence. Real-time quantitative PCR and flow cytometry results showed that, compared with non-transfected PC12 cells, adenovirus-mediated estrogen receptor β gene-transfected PC12 cells exhibited lower expression of tumor necrosis factor a and interleukin 1β under stimulation with beta-amyloid protein and stronger protection from apoptosis. The Akt-specific inhibitor Abi-2 decreased the anti-inflammatory and anti-apoptotic effects of estrogen receptor β gene-transfection. These findings suggest that overexpression of estrogen receptor β can alleviate the toxic effect of beta-amyloid protein on PC12 cells, without estrogen dependence. The Akt pathway is one of the potential means for the anti-inflammatory and anti-apoptotic effects of the estrogen receptor.

Gengnianchun recipe inhibits apoptosis of pheochromocytoma cells from beta-amyloid 25-35 insult, better than monotherapies and their compounds

This study aims to determine and compare the protective effects of Gengnianchun recipe drug serum and compounds of its representative drug monotherapies against sympathetic nerve pheochromocytoma cell line PC12 cells damaged by beta-amyloid 25-35 at the cellular apoptosis and related signal pathway levels. PC12 cells cultured with medicated rat serum showed enhanced cell viability and reduced cellular apoptosis rates compared with those of monotherapies and their compounds. Furthermore, Gengnianchun recipe up-regulated expressions of anti-apoptotic protein Bcl-2, estrogen receptor-beta and phosphorylated extracellular-signal-regulated kinase 1/2; and down-regulated expressions of pro-apoptotic proteins Bax and caspase-3. Gengnianchun recipe was superior to representative drug monotherapies, such as paeoniflorin, berberine, timosaponin A-III, icariine and their compounds in protecting PC12 cells. Mitogen-activated protein kinase blocker and estrogen receptor antagonist were found to reverse the above effects of Gengnianchun recipe. The experimental findings indicate that, Gengnianchun recipe protects PC12 cells from beta-amyloid 25-35 insult; its inhibitory effect on apoptosis may be achieved through the mitogen-activated protein kinase and estrogen receptor pathways.

Telencephalin protects Paju cells from beta-amyloid protein-induced apoptosis

Previous studies have confirmed that telencephalin （TLN） is a neural glycoprotein that protects axonal disruption induced by the beta-amyloid protein （Aβ42/35） in the neural crest-derived tumor cell line Paju. The present study investigated the effects of TLN on neuronal degeneration induced by Aβ42 in the differentiated Paju cell line. Results demonstrated that after cultivating cells in Aβ42 medium, the survival rate of Paju-TLN cells was significantly higher than that of Paju-neo cells, and that apoptotic rate was noticeably reduced. These results indicate that TLN reduces Paju cell apoptosis induced by Aβ42.

Effects of long-term estrogen replacement therapy on beta-amyloid precursor protein and mRNA expression in ovariectomized rat hippocampus

BACKGROUND： In vitro cultures of neural stem cells have shown that estrogen can regulate beta-amyloid precursor protein （β-APP） metabolism and reduce amyloid-beta production. OBJECTIVE： To investigate the effects of long-term oral administration of compound nylestriol or low-dose 17beta-estradiol on β-APP and mRNA expression in the hippocampus of ovariectomized （OVX） rats. DESIGN, TIME AND SETTING： This randomized and controlled experiment was performed at the Animal Laboratory and Laboratory of Endocrine and Metabolic Disease, Xiangya Second Hospital of Central South University between April 2003 and May 2004. MATERIALS： According to body mass, 50 six-month-old female Sprague-Dawley rats were randomly divided into five groups （n = 10 per group）： normal control, sham operation, OVX model, 17beta-estradiol （Sigma, USA）, and compound nylestriol tablet （Laboratory of Endocrine and Metabolic Disease, Xiangya Second Hospital of Central South University） groups. METHODS： Rats in OVX plus 17beta-estradiol and OVX plus compound nylestriol tablet groups underwent ovariectomy. On the second day after surgery, rats were intragastrically given 17beta-estradiol （100 μg/kg）, once per day or compound nylestriol tablet （0.5 mg/kg） and levonorgestrel （0.15 mg/kg） every 2 days. MAIN OUTCOME MEASURES： β-APP expression in the hippocampus of OVX rats was determined using immunohistochemistry （SABC method） and β-APP mRNA expression was analyzed by in situ hybridization. The results were quantitatively analyzed using cell counting and average optical density. RESULTS： The number and optical density of β-APP-positive neurons in every subregion of the hippocampus of OVX rats was dramatically increased compared with normal and sham operation groups following 35 weeks of administration （P 〈 0.05）. Levels of β-APP were decreased following oral administration of compound nylestriol or 17beta-estradiol. In situ hybridization showed that long-term estrogen deficiency and oral administration of compound nylestriol or 17beta-estradiol did not alter the number of β-APP mRNA-positive neurons. CONCLUSION： The results show that long-term estrogen deficiency results in an increase of expression of β-APP though no changes in the expression of β-APP mRNA are detected. Replacement of estrogen with low-dose 17 beta-estradiol or compound nylestriol tablet inhibits the expression of β-APP in the hippocampus to the same extent.

Tau protein,phosphorylated tau protein,and beta-amyloid 42 levels in patients with neurodegenerative diseases complicated by cognitive deficits A non-randomized,concurrent,case-control investigation

BACKGROUND： The differential diagnosis of many neurodegenerative disorders depends primarily on clinical symptoms together with imaging methods. Recently, increased importance has been placed on the use of biomarkers for diagnosing various neurodegenerative disorders. OBJECTIVE： To assess the feasibility of tau-protein, phosphorylated tau-protein, beta-amyloid 42 （Aβ42）, and 14-3-3 protein as biomarkers for diagnosing several neurodegenerative diseases complicated by cognitive deficits. DESIGN, TIME AND SETTING： A non-randomized, concurrent, case-control investigation was performed in three medical centers in the Czech Republic （Department of Neurology at the University Hospital in Hradec Kralove, Department of Neurology at the 2rd Medical Faculty, and the University Hospital Motol） between October 2000 and November 2006. PARTICIPANTS： Eighteen patients with probable AIzheimer＇s disease, 4 patients with Creutzfeldt-Jakob disease, 10 patients with frontotemporal dementia, 9 patients with clinically isolated syndrome suggestive of multiple sclerosis, and 7 patients with multiple sclerosis, as well as 38 race-, nationality-, and age-matched cognitively intact controls, were included in the study. Diagnoses were established based on the following criteria： the criteria for Alzheimer＇s disease proposed by the National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer＇s Disease and Related Disorders Association, WHO criteria for Creutzfeldt-Jakob disease, Neary criteria for frontotemporal dementia, and McDonald＇s criteria for multiple sclerosis. All included patients were confirmed to suffer from various degrees of dementia. METHODS： Enzyme-linked immunosorbent assay was used to measure concentrations of tau-protein, phosphorylated tau-protein, and Aβ42 in cerebrospinal fluid （CSF） samples collected by standard lumbar puncture from each patient. Moreover, 14-3-3 protein was assessed by Western blot in CSF of Creutzfeldt-Jakob disease patients. Cognitive status was assessed using the Mini Mental Scale Examination （MMSE） in all subjects. MAIN OUTCOME MEASURES： Establishment of biomarkers with greatest specificity and sensitivity for the investigated disorders according to Receiver Operating Characteristic curves, which were based on values from patients and controls; correlation between concentrations of given biomarkers and demographic parameters, diagnosis, duration of disease, and level of cognitive deficit. RESULTS： Increased concentrations of total tau protein and phosphorylated tau protein, and decreased levels of Aβ42, in CSF of Alzheimer＇s disease patients reached the required sensitivity/specificity ratio of 80% or greater. A marked elevation in CSF concentrations of total tau protein showed even greater sensitivity than 14-3-3 protein in Creutzfeldt-Jakob disease. There was no association between selected biomarkers and frontotemporal dementia or multiple sclerosis. Phosphorylated tau-protein was the only biomarker that noticeably correlated with MMSE scores for Alzheimer＇s disease.CONCLUSION： Levels of total tau protein, phosphorylated tau protein, and A!342 in the CSF could differentiate patients with Alzheimer＇s disease and Creutzfeldt-Jakob disease from healthy controls and patients with other neurodegenerative disorders. The diversity of absolute values demonstrates the necessity to establish a specific standard for each laboratory.

Curcumin inhibits beta-amyloid protein 40/42 expression in the brain in a concentration-and time-dependent manner

Several studies have demonstrated that the amount of beta-amyloid （Aβ） protein in the brain can be lowered by down-regulating Aβ production, promoting Aβ degradation, reducing Aβ oligomerization or deposition, thereby alleviating symptoms of Alzheimer＇s disease. Curcumin has been known to be a peroxisome proliferator activated receptor gamma （PPARy） agonist and can obviously inhibit Aβ production and oligomerization. This study investigated the effects of curcumin on the G-site APP cleaving enzyme 1 （BACE1） activity and PPARy expression in human neuroblastoma SH-SY5Y cells, and validated the inhibitory effects of curcumin on Aβ40/42 expression in the brain. Results revealed that PPARy mRNA and protein expression in the human neuroblastoma SH-SY5Y cells significantly increased with increasing curcumin concentration and time course （P 〈 0.05）; BACE1 mRNA and protein expression and Aβ40/42 production significantly decreased with increasing curcumin concentration and time course （P 〈 0.05）. The changes in PPARy and BACE1 expression during Aβ production could be reversed by the PPARy antagonist GW9662. These findings indicate that curcumin reduced Aβ production by activating PPARy expression and inhibiting BACE1 expression in a concentration- and time-dependent manner.

Spatial structure of beta-amyloid Aβ_(1-40) in complex with a biological membrane model

The spatial structure of beta-amyloid Aβ1-40 in complex with sodium dodecyl sulfate micelles as a model membrane system was investigated by 1H-1H two-dimensional NMR (TOCSY, NOESY) spectroscopy and molecular dynamic method calculations. On the basis of NOE and chemical shifts changes data, spatial structure of the complex beta-amyloid-model of the cell surface membrane was obtained.

High-frequency magnetic stimulation attenuates beta-amyloid protein 1-42 neurotoxicity in organotypic hippocampal slices

Repetitive transcranial magnetic stimulation （rTMS） has been utilized as a therapeutic tool for neurodegenerative disorders including Alzheimer＇s disease. However, the precise mechanisms of its clinical effects remain unknown. β-amyloid （Aβ） exhibits direct neurotoxic effects and is closely related to neuronal degeneration in Alzheimer＇s disease. Therefore, it has been hypothesized that the neuroprotective effects of rTMS are related to the mechanisms of protection against Aβ neurotoxicity. Organotypic hippocampal slices were prepared from 8-day old, Sprague Dawley rats. The tissue slices were exposed to 100 μmol/L Al3142 since day 12 in vitro with and without high-frequency （20 Hz） magnetic stimulation. Magnetic stimulation efficacy was evaluated by measuring neuronal nuclei （NeuN） protein expression and by observing cultures following propidium iodide fluorescence staining and bromodeoxyuridine （BrdU） immunohistochemistry. Lactate dehydrogenase activity was detected in the culture media to evaluate hippocampal neuronal damage. Our results demonstrated that high-frequency magnetic stimulation significantly reversed the reduction of NeuN protein expression because of Aβ1-42 exposure （P 〈 0.05） and significantly reduced the number of damaged cells in the hippocampal slices （P 〈 0.05）. However, lactate dehydrogenase levels and anti-BrdU staining results did not reveal any statistical differences These findings indicate that high-frequency magnetic stimulation might have protective effect on hippocampal neurons from Aβ1-42 neurotoxicity.

Effects of natural cerebrolysin on protective proteins and pro-apoptotic molecules in mesenchymal stem cells following beta-amyloid peptide1-40-induced endoplasmic reticulum stress

BACKGROUND： Studies have demonstrated that β-amyloid peptide （Aβ）, a characteristic pathological product of Alzheimer＇s disease （AD）, results in neuronal endoplasmic reticulum stress （ERS）. However, the mechanisms of traditional Chinese medicine against ERS in AD are poorly understood. OBJECTIVE： To measure expression levels of protective proteins （GRP78 and GRP94） of ER molecular partners and pro-apoptotic Caspase-12 ER membrane expression following application of traditional Chinese medicine natural cerebrolysin （NC） to treat Aβ1-40-induced ERS. DESIGN, TIME AND SETTING： A parallel-controlled study was performed at the Institute of Integrated Western and Traditional Chinese Medicine, Shenzhen Hospital of Southern Medical University between September 2006 and November 2008. MATERIALS： Sprague Dawley male rats, 6-8 weeks old, were used to harvest tibial and femoral bone marrow. Isolation and purification of mesenchymal stem cells （MSCs） were established from the whole bone marrow by removing non-adherent cells in primary and passage cultures. Aβ1-40 was provided by Sigma, USA. NC was provided by Shenzhen Institute of Integrated Chinese and Western Medicine, China. NC was predominantly composed of Renshen （Radix Ginseng）, Tianma （Rhizoma Gastrodiae）, and Yinxingye （Ginkgo Leaf） in a proportion of 1 ： 2： 2. Following conventional water extraction technology, an extract （1 ： 20） was prepared. Six adult, male, New Zealand rabbits underwent intragastric administration of NC extract （0.976 g/kg per day） for 1 month to prepare NC-positive serum, and the remaining 6 rabbits received intragastric administration of physiological saline to prepare normal blank serum. METHODS： A total of 500 nmol/L Aβ1-40 was used to establish ERS models of primary cultured MSCs. AD cell models were incubated with different doses of NC-positive serum （2.5%, 5%, and 10%）. MSCs treated with normal blank serum served as normal blank controls. MAIN OUTCOME MEASURES： Reverse transcription-polymerase chain reaction and fluorescent immunocytochemistry were respectively used to measure mRNA and protein expression levels of GRP78, GRP94, and Caspase-12 in MSCs. RESULTS： Following Aβ1-40 exposure, mRNA and protein expression levels of GRP78 and GRP94, as well as Caspase-12, significantly increased （P 〈 0.05）, suggesting successful establishment of ERS models. Following NC-positive serum application, mRNA and protein expression levels of GRP78 and GRP94 in MSCs significantly increased （P 〈 0.05 or P 〈 0.01）. However, mRNA and protein expression levels of Caspase-12 significantly decreased （P 〈 0.05, or P 〈 0.01） compared with the ERS model group. These effects were dose-dependent. CONCLUSION： NC downregulated Caspase-12 expression and upregulated GRP78 and GRP94 expression in MSCs in a dose-dependent manner under the state of Aβ1-40-induced ERS.

Nasal mucosal inhalation of amyloid-beta peptide 3–10 defective adenovirus attenuates cytotoxicity induced by beta-amyloid(1–42)

Three-month-old Alzheimer＇s disease model transgenic mice were immunized with Aβ1-42, Plp-Adenovirus [Ad]-X-CMV-（Aβ3-10）lo-CpG [AdCpG-（Aβ3-10）1] or AdCpG virus fluid via na- sal mucosal inhalation, respectively. ELISA analysis of serum showed Aβ42 antibody titers were significantly increased in mice immunized with Aβ1-42 and AdCpG-（Aβ3-10）10. Concanavalin A and AdCpG-（Aβ3-10）10 stimulation significantly increased the number of proliferating spleen cells cultured from AdCpG（Aβ3-10）Io and Aβ42 groups compared with the control group. In the AdCp- G（Aβ3-10）10 group, levels of interleukin （IL）-4 and IL-10 were increased, while those of IL-2 and interferon-y were decreased. In the A[342 group, levels of IL-4, IL-10, IL-2 and interferon-y were all increased. Experimental findings indicate that AdCpG-（Aβ3-10）10 vaccine can produce strong T helper 2 （Th2） humoral immune responses in addition to the production of Aβ42 antibody. The cellular immunologic response was weak and avoided Aβ1-42-mediated cytotoxicity.

EEG/ERP evidence of possible hyperexcitability in older adults with elevated beta-amyloid

Background: Although growing evidence links beta-amyloid (Aβ) and neuronal hyperexcitability in preclinical mouse models of Alzheimer’s disease (AD), a similar association in humans is yet to be established. The first aim of the study was to determine the association between elevated Aβ (Aβ+) and cognitive processes measured by the P3 event-related potential (ERP) in cognitively normal (CN) older adults. The second aim was to compare the event- related power between CNAβ+ and CNAβ−. Methods: Seventeen CNAβ+ participants (age: 73 ± 5, 11 females, Montreal Cognitive Assessment [MoCA] score 26 ± 2) and 17 CNAβ- participants group-matched for age, sex, and MOCA completed a working memory task (n-back with n = 0, 1, 2) test while wearing a 256-channel electro-encephalography net. P3 peak amplitude and latency of the target, nontarget and task difference effect (nontarget−target), and event-related power in the delta, theta, alpha, and beta bands, extracted from Fz, Cz, and Pz, were compared between groups using linear mixed models. P3 ampli-tude of the task difference effect at Fz and event-related power in the delta band were considered main outcomes. Correlations of mean Aβ standard uptake value ratios (SUVR) using positron emission tomography with P3 amplitude and latency of the task difference effect were analyzed using Pearson Correlation Coefficient r. Results: The P3 peak amplitude of the task difference effect at Fz was lower in the CNAβ+ group (P = 0.048). Simi-larly, power was lower in the delta band for nontargets at Fz in the CNAβ+ participants (P = 0.04). The CNAβ+ partici-pants also demonstrated higher theta and alpha power in channels at Cz and Pz, but no changes in P3 ERP. Strong correlations were found between the mean Aβ SUVR and the latency of the 1-back (r = − 0.69;P = 0.003) and 2-back (r = − 0.69;P = 0.004) of the task difference effect at channel Fz in the CNAβ+ group. Conclusions: Our data suggest that the elevated amyloid in cognitively normal older adults is associated with neuronal hyperexcitability. The decreased P3 task difference likely reflects early impairments in working memory processes. Further research is warranted to determine the validity of ERP in predicting clinical, neurobiological, and functional manifestations of AD.

β-淀粉样蛋白调控miR-15a激活Bag5在阿尔茨海默病神经细胞凋亡中的作用

目的:阿尔茨海默病(Alzheimer’s disease,AD)的患病率在全球范围内不断增加,然而其发病机制尚不清楚。研究表明AD的进展与神经细胞凋亡密切相关。本研究旨在探讨miR-15a和Bag5在β-淀粉样蛋白(β-amyloid protein,Aβ)诱导的AD神经细胞凋亡中的作用及其具体机制。方法:通过给SD大鼠脑部注射Aβ42构建AD大鼠模型,并使用Aβ42处理SH-SY5Y细胞构建AD细胞模型。采用莫里斯(Morris)水迷宫实验检测大鼠的学习记忆能力;苏木精-伊红(hematoxylin and eosin,HE)染色检测大鼠脑组织的病理变化;尼氏(Nissl)染色检测脑组织中细胞形态以及数量变化;生物信息学分析筛选与Bag5相互作用的上游miRNA;四甲基偶氮唑盐(methyl thiazolyl tetrazolium,MTT)检测细胞增殖能力;流式细胞术检测细胞的凋亡率;实时反转录聚合酶链反应(real-time reverse transcription PCR,real-time RT-PCR)检测miR-15a和Bag5的mRNA水平;蛋白质印迹法检测Bag5、Bax和Caspase-3的蛋白质表达水平。分别采用miR-15a敲减或过表达载体以及Bag5敲减载体处理大鼠和细胞,萤光素酶报告实验验证miR-15a与Bag5之间的结合关系。结果:Morris水迷宫实验、HE染色和Nissl染色结果表明AD大鼠模型成功建立,且Aβ可诱导AD大鼠中神经细胞凋亡和抑制miR-15a表达。与正常细胞相比,Aβ处理可显著增加细胞凋亡率和Bag5的表达,降低细胞活力和miR-15a表达,过表达miR-15a会进一步加强Aβ对细胞增殖和凋亡的效果,而敲减miR-15a的表达则起到相反的作用(均P<0.01)。萤光素酶报告实验证明miR-15a与Bag5存在负向靶向关系。且与单独敲减Bag5相比,敲减miR-15a和Bag5共转染会显著提高细胞活力以及Bag5的表达,同时明显降低细胞的凋亡率以及Bax、Caspase-3的表达,体内实验也得到一致的结果(均P<0.01)。结论:Aβ可抑制miR-15a的表达,进而诱导Bag5表达,以激活Bag5对于Aβ引起凋亡的保护作用。

关于抗Aβ单克隆抗体的临床应用建议(2024版)

最新研发的抗Aβ单克隆抗体陆续在国内外获批上市,并逐渐应用于我国临床实践。为促进抗Aβ单克隆抗体在我国阿尔茨海默病治疗中更合理、安全的应用,本文结合抗Aβ单克隆抗体现有临床试验证据及阿杜卡单抗在上海交通大学医学院附属瑞金医院海南医院的临床应用经验,总结抗Aβ单克隆抗体的临床应用建议,包括临床用药指征、用药前评估及准备、用药时医嘱及注意事项、用药后临床监测,旨在为临床医师提供翔实的用药指导和建议。

缺血性脑血管病患者血清β淀粉样蛋白和壳多糖酶3样蛋白1水平与颈动脉病变的关系

目的探讨缺血性脑血管病(ICD)患者血清β淀粉样蛋白(Aβ)和壳多糖酶3样蛋白1(CHI3L1)水平与颈动脉病变的关系。方法选取2019年1月—2023年5月沧州市中心医院ICD患者298例(ICD组)、健康体检者300名(对照组)。根据颈动脉内膜中层厚度(ITM)、斑块积分和颈动脉狭窄程度分别分组。收集所有研究对象一般资料,并检测血清Aβ、CHI3L1、糖化血红蛋白(Hb A1c)、三酰甘油(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)水平。采用偏相关分析评估血清Aβ、CHI3L1水平与颈动脉病变的相关性。结果ICD组血清TG、TC、LDL-C、Aβ和CHI3L1水平均高于对照组(P<0.01),其他指标2个组之间差异均无统计学意义(P>0.05)。内膜正常组、内膜增厚组、斑块形成组血清Aβ和CHI3L1水平依次升高(P<0.001)。轻度硬化组、中度硬化组和重度硬化组血清Aβ和CHI3L1水平依次升高(P<0.001)。轻度狭窄组、中度狭窄组和重度狭窄组血清Aβ、CHI3L1水平依次升高(P<0.001)。血清Aβ和CHI3L1水平与ITM、斑块积分和颈动脉狭窄程度均呈正相关(P<0.001)。结论ICD患者血清Aβ和CHI3L1水平升高,且与颈动脉病变密切相关,或可作为反映ICD患者颈动脉病变程度的指标。

MicroRNA-137-5p靶向USP30改善阿尔茨海默病

目的 探索miR-137-5p对阿尔茨海默病(AD)的保护机制。方法 首先用qRT-PCR评估AD患者和健康对照组人血清中miR-137和USP30的表达。用D-半乳糖和氯化铝建立AD小鼠模型,用水迷宫试验检测小鼠的行为,确认AD小鼠模型的成功。用Aβ1-42寡聚体诱导的SH-SY5Y细胞建立AD细胞模型,通过实时定量聚合酶链反应检测AD模型中miR-137-5p和USP30的表达。双重荧光素酶试验用于验证miR-137-5p和USP30之间的靶向结合关系。结果 miR-137-5p的表达在AD患者中与健康对照组相比有所下降(P<0.05),而USP30则明显增加(P<0.05)。miR-137-5p能改善AD细胞模型中的细胞凋亡,USP30的过表达部分废除了miR-137-5p对Aβ1-42-处理的SH-SY5Y细胞的影响,miR-137-5p通过靶向USP30改善AD小鼠的认知能力和Aβ的沉积。结论 miR-137-5p可以通过下调USP30来改善AD症状,miR-137-5p可能能成为治疗AD的一个靶点。

The Effect of Curcumin on Alzheimer’s Disease

Alzheimer’s disease (AD) is the most prevalent type of dementia, affecting approximately 50 million individuals globally, and projections indicate that this number will increase to 139 million by 2050. It is one of the main factors contributing to cognitive decline in the aging population. Existing treatments do not produce the intended therapeutic benefits;therefore, it is imperative to identify alternative pharmacological and biological techniques. As the precise pathogenic pathways underlying AD remain unknown, existing therapies only address symptoms rather than promote prevention or treatment. Curcumin has attracted increasing attention owing to its distinct molecular structure. It affects antioxidant and inflammatory pathways as well as amyloid aggregation, which is one of the main characteristics of Alzheimer’s disease. Many human ailments have been treated with medicinal plants, owing to their antioxidant properties. Curcumin has been used as a traditional food and medicine in Asia for a long time. Numerous studies have shown that curcumin has several advantageous properties including anti-inflammatory and antioxidant activities. Numerous clinical trials have been conducted to clarify the impact of curcumin on cancers, owing to its documented effects on tumors. Recent findings suggest that curcumin may have therapeutic potential in the pathogenesis of Alzheimer’s disease (AD). The overall memory of patients with AD has improved because of several benefits of curcumin, including decreased beta-amyloid plaques, delayed neuronal degradation, metal chelation, anti-inflammatory and antioxidant effects, and decreased microglial production.