A study on factors associated with age of Alzheimer's disease onset / 中华流行病学杂志

Objective: To understand the distribution characteristics of age of Alzheimer's disease (AD) onset and influencing factors. Methods: Based on the follow-up data of Alzheimer's Disease Neuroimaging Initiative from 2005 to 2022, participants with normal cognition (CN) or mild cognitive impairment (MCI) at baseline survey, and those with progression to AD during follow-up period were selected as study subjects. Univariate analysis and multiple linear regression analysis were performed to explore the associations of gender, race, number of ApoE ε4 genes carried, family history, years of education and marital status with the age of AD onset. Results: A total of 405 participants, with an average age of (74.0±6.9) years at baseline survey, progressed to AD during follow up period. The age of AD onset was (76.6±7.5) years, and age of onset in men was about 1.9 years later than women. Multiple linear regression analysis showed that for each increase in ApoE ε4 gene number, the age of AD onset was about 0.344 years earlier. The age of AD onset was 4.007 years earlier for those with MCI at baseline survey compared with those with CN. Years of education were not significantly associated with the age of onset of AD (P>0.05). Conclusion: Those who carry ApoE ε4 gene, and have MCI at baseline survey might have earlier age of AD onset.

Effect on Danggui Shaoyao Powder on mitophagy in rat model of Alzheimer's disease based on PINK1-Parkin pathway / 中国中药杂志

This study investigated the mechanism of Danggui Shaoyao Powder(DSP) against mitophagy in rat model of Alzheimer's disease(AD) induced by streptozotocin(STZ) based on PTEN induced putative kinase 1(PINK1)-Parkin signaling pathway. The AD rat model was established by injecting STZ into the lateral ventricle, and the rats were divided into normal group, model group, DSP low-dose group(12 g·kg~(-1)·d~(-1)), DSP medium-dose group(24 g·kg~(-1)·d~(-1)), and DSP high-dose group(36 g·kg~(-1)·d~(-1)). Morris water maze test was used to detect the learning and memory function of the rats, and transmission electron microscopy and immunofluorescence were employed to detect mitophagy. The protein expression levels of PINK1, Parkin, LC3BⅠ/LC3BⅡ, and p62 were assayed by Western blot. Compared with the normal group, the model group showed a significant decrease in the learning and memory function(P<0.01), reduced protein expression of PINK1 and Parkin(P<0.05), increased protein expression of LC3BⅠ/LC3BⅡ and p62(P<0.05), and decreased occurrence of mitophagy(P<0.01). Compared with the model group, the DSP medium-and high-dose groups notably improved the learning and memory ability of AD rats, which mainly manifested as shortened escape latency, leng-thened time in target quadrants and elevated number of crossing the platform(P<0.05 or P<0.01), remarkably activated mitophagy(P<0.05), up-regulated the protein expression of PINK1 and Parkin, and down-regulated the protein expression of LC3BⅠ/LC3BⅡ and p62(P<0.05 or P<0.01). These results demonstrated that DSP might promote mitophagy mediated by PINK1-Parkin pathway to remove damaged mitochondria and improve mitochondrial function, thereby exerting a neuroprotective effect.

Correlation of serum lipids levels of Alzheimer's disease patients with sex, age and apolipoprotein E gene polymorphism / 中华预防医学杂志

Objective: To explore the correlation of serum lipids levels of Alzheimer's disease (AD) patients with sex, age and apolipoprotein E (Apo E) gene polymorphism. Methods: The retrospective study method was used, and 407 AD patients (142 males and 265 females, aged 52-91 years) were selected from Beijing Tiantan Hospital from January 2015 to August 2021 as the research target, and 894 healthy persons (339 males and 555 females, aged 52-94 years) who did body examination were selected as the control group. The AD patients were divided into four age groups according to the age interval of 10 years, including 85 aged 50-59 years, 163 aged 60-69 years, 119 aged 70-79 years, and 40 aged more than 80 years. The serum lipids levels were detected by biochemical analyzer, including triglycerides (TG), cholesterol (CHO), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), apolipoproteinA1(Apo A1) and apolipoprotein B (Apo B). ApoE gene polymorphism were detected by PCR fluorescent probe method. Mann-Whitney U test and Kruskal-Wallis H test were used to compare the serum lipids levels in each group. Results: The levels of serum CHO and LDL-C were 3.30(1.41,4.82) mmol/L and 1.76(1.39,2.78) mmol/L in AD patients, and 4.84(4.24, 5.56) mmol/L and 2.91(2.36, 3.57) mmol/L in control group, and the levels of serum CHO and LDL-C of AD patients were significantly lower than control group (Z=-15.172,Z=-14.583 , P<0.001, P<0.001). The levels of serum HDL-C and Apo B were 1.84(1.30, 3.88) mmol/L and 1.17(0.85, 1.57) g/L in AD patients, and 1.39(1.18, 1.64) mmol/L and 0.93(0.81, 1.09) g/L in control group, and the levels of serum HDL-C and Apo-B of AD patients were significantly higher than control group (Z=-12.249 , Z=-9.706 , P<0.001, P<0.001). There was no significant difference in TG and Apo A1 between 2 groups (Z=-1.577 , Z=-0.408 , P=0.115, P=0.683). The levels of TG, CHO, LDL-C in female AD patients were significantly higher than male patients (Z=-2.737 , Z=-3.963 , Z=-4.417, P=0.006, P<0.001, P<0.001). There were significant differences in TG, CHO, HDL-C, LDL-C, Apo A1 and Apo B among AD patients of all age groups (Z=11.263 , Z=10.060 , Z=40.246 , Z=10.451 , Z=24.315 , Z=19.922 , P=0.010 , P=0.018 , P<0.001 , P=0.015 , P<0.001 , P<0.001). The serum CHO and LDL-C levels were positively correlated with age (rs=0.160, rs=0.174, P=0.001, P<0.001), and HDL-C, Apo A1 and Apo B levels were negatively correlated with age (rs=-0.312, rs=-0.272, rs=-0.146, P<0.001, P<0.001, P=0.003), and there was no correlation between TG level and age in AD patients (rs=0.086, P=0.082). There were 3 cases (3.33%) of E2, 43 cases of E3 (47.78%) and 44 cases of E4 (48.89%) in AD patients, and 22 cases (12.72%) of E2, 117 cases of E3 (67.63%) and 34 cases of E4 (19.65%) in control group. There was significant difference in Apo E genotype distribution between AD patients and control group (χ²=26.381 , P<0.001). Apo E4 was the most common genotype in AD patients, and the proportion was 48.89%. Except for Apo A1(Z=7.821 , P=0.020), there was no significant difference in TG, CHO, HDL-C, LDL-C and Apo B levels among all patients with different genotypes (Z=3.732 , Z=1.677 , Z=1.455 , Z=1.619 , Z=2.202 , P=0.155, P=0.432, P=0.483, P=0.445, P=0.333). Conclusion: The levels of CHO and LDL-C decreased while the levels of HDL-C and Apo B increased in AD patients. The dyslipidemia in AD patients might be correlated with age, but not sex and Apo E genotypes.

Effects of TYROBP Deficiency on Neuroinflammation of a Alzheimer's Disease Mouse Model Carrying a PSEN1 p.G378E Mutation / 中国医学科学杂志(英文版)

Objective To study the effects of TYRO protein kinase-binding protein (TYROBP) deficiency on learning behavior, glia activation and pro-inflammatory cycokines, and Tau phosphorylation of a new Alzheimer's disease (AD) mouse model carrying a PSEN1 p.G378E mutation.Methods A new AD mouse model carrying PSEN1 p.G378E mutation was built based on our previously found AD family which might be ascribed to the PSEN1 mutation, and then crossed with TYROBP deficient mice to produce the heterozygous hybrid mice (PSEN1G378E/WT; Tyrobp+/-) and the homozygous hybrid mice (PSEN1G378E/G378E; Tyrobp-/-). Water maze test was used to detect spatial learning and memory ability of mice. After the mice were sacrificed, the hippocampus was excised for further analysis. Immunofluorescence was used to identify the cell that expresses TYROBP and the number of microglia and astrocyte. Western blot was used to detect the expression levels of Tau and phosphorylated Tau (p-Tau), and ELISA to measure the levels of pro-inflammatory cytokines. Results Our results showed that TYROBP specifically expressed in the microglia of mouse hippocampus. Absence of TYROBP in PSEN1G378E mutation mouse model prevented the deterioration of learning behavior, decreased the numbers of microglia and astrocytes, and the levels of interleukin-6, interleukin-1β and tumor necrosis factor-α in the hippocampus (all P < 0.05). The ratios of AT8/Tau5, PHF1/Tau5, pT181/Tau5, pT231/Tau5 and p-ERK/ERK were all higher in homozygous hybrid mice (PSEN1G378E/G378E; Tyrobp-/- mice) compared with PSEN1G378E/G378E mice (all P < 0.05). Conclusions TYROBP deficiency might play a protective role in the modulation of neuroinflammation of AD. However, the relationship between neuroinflammation processes involving microglia and astrocyte activation, and release of pro-inflammatory cytokines, and p-Tau pathology needs further study.

Network pharmacology-based study of the therapeutic mechanism of resveratrol for Alzheimer's disease / 南方医科大学学报

OBJECTIVE@#To investigate the therapeutic mechanism of resveratrol (RES) for Alzheimer's disease (AD) in light of network pharmacology.@*METHODS@#We searched PubChem, BATMAN-TCM, Genecards, AD, TTD, String 11.0, AlzData, SwissTargetPrediction, Metascape and other databases for the therapeutic targets of RES and human AD-related targets. The intersection was determined using Venny 2.1 to obtain the therapeutic targets of RES for AD. The protein-protein interaction (PPI) network was constructed, the gene ontology (GO) was enriched and the Kyoto Encyclopedia of Genes and Genomes pathway (KEGG pathway) were analyzed. Cytoscape 3.7.1 software was used to construct a target-signaling pathway network of RES in the treatment of AD. Molecular docking verification was carried out on SwissDock (http://www.swissdock.ch/docking). We examined a 293Tau cell model of AD for changes in protein levels of pS396, pS199, Tau5, CDK5, glycogen synthase kinase 3β (GSK3β) and p-GSK3β in response to RES treatment using Western blotting.@*RESULTS@#We obtained 182 targets of RES, 525 targets related to AD, and 36 targets of RES for AD treatment, among which 34.6% of the targets were protein-modifying enzymes, 27.7% were metabolite invertase, 13.8% were gene-specific transcriptional regulators, and 10.3% were transporters. The core key targets of RES in the treatment of AD included INS, APP, ESR1, MMP9, IGF1R, CACNA1C, MAPT (microtubule- associated protein Tau), MMP2, TGFB1 and GSK3B. Enrichment analysis of GO biological process suggested that the biological function of RES in AD treatment mainly involved the response to β-amyloid protein, positive regulation of transferase activity, the transmembrane receptor protein tyrosine kinase signaling pathway, regulation of behavior, learning or memory, aging, and transmembrane transport. KEGG pathway enrichment analysis showed that the most significantly enriched signaling pathways were AD pathway, PI3K-AKT signaling pathway, cGMP-PKG signaling pathway, and MAPK signaling pathway. Molecular docking results showed that RES had strong binding with ESR1, GSK3B, MMP9, IGF1R, APP and INS. In the cell model of AD, treatment with 50 μmol/L RES for 12 h significantly reduced the levels of pS396 and pS199 by regulating CDK5 and GSK3β activity (@*CONCLUSIONS@#RES produces therapeutic effects on AD by acting on multiple targets and affecting multiple signaling pathways and improves AD-associated pathologies

Early / 中南大学学报(医学版)

Alzheimer's disease (AD) is the most common senile neurodegenerative disease characterized by progressive cognitive dysfunction, psychological and behavioral abnormalities, and impaired ability of activities of daily living. A family with a total of 3 patients were admitted to the Department of Neurology of Xiangya Hospital, Central South University in 2018. The proband showed memory decline as the presenting symptoms, and subsequently showed psychological and behavioral abnormalities, personality changes, seizures, and motor retardation. Definite diagnosis of early-onset familial AD (EOFAD) with missense mutation of presenilin 2 (PSEN2) (c.715A>G p.M239V) was established by whole exome sequencing (WES) technology. We reported the mutation in Chinese Han population for the first time, which expanded the mutation spectrum ofPSEN2 gene and aid to enrich the characterization of clinical phenotype in EOFAD associated to PSEN2 mutations. Patients with early onset age and complex clinical manifestations of AD can be diagnosed with the help of genetic testing to avoid misdiagnosis.

Mechanism of volatile oil from Alpinia oxyphylla in treating Alzheimer's disease based on GC-MS and network pharmacology / 中国中药杂志

To study the material basis and mechanism of volatile oil from Alpinia oxyphylla in treating Alzheimer's disease(AD) based on GC-MS and network pharmacology. Ingredients of volatile oil from A.oxyphylla were analyzed by GC-MS. Targets of those ingredients were obtained through Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP). Relevant targets of AD were obtained through such databases as DrugBank, STITCH, OMIM. Intersection targets of ingredients and diseases were obtained by Online Venny map, and PPI network was established by STRING to screen out core targets. Gene ontology(GO) functional enrichment analysis and KEGG pathway enrichment analysis were performed by DAVID. The "ingredients-target-pathway" network was constructed by software Cytoscape 3.8.1 to screen out potential active ingredients of volatile oil from A.oxyphylla in the treatment of AD. The results showed that a total of 6 active ingredients were screened from the volatile oil of A.oxyphylla by GC-MS, 17 targets corresponding to 6 active ingredients were found in TCMSP database, and 3 448 AD targets were found in DrugBank database. "Ingredients-target-pathway" network and PPI network showed there were 4 potential active ingredients in the treatment of AD and 4 core targets. GO analysis and KEGG analysis showed 34(P<0.05) and 5(P<0.05) pathways, respectively, including nerve ligand receptor interaction, calcium signaling pathway, cholinergic synapse and 5-hydroxytryptaminergic synapse. This suggested that volatile oil from A.oxyphylla could synergistically treat AD by regulating calcium balance, cholinergic balance and phosphorylation. This study provided reference and guidance for further study of volatile oil from A.oxyphylla in the treatment of AD.

Research progress on bidirectional effect of microRNA on Alzheimer's disease and intervention with traditional Chinese medicine / 中国中药杂志

Alzheimer's disease(AD) is a chronic progressive neurodegenerative disease with recent memory impairment as the main clinical manifestation and senile plaques and neurofibrillary tangles as the main pathological changes. In recent years, the effect of microRNAs on AD has attracted widespread attention. Patients with AD have abnormal expression of miRNA, which is closed related to regulation of AD pathophysiology-related genes. Therefore, this paper first elaborated neuroprotective and toxic effects of microRNA in AD, and then explored relevant traditional Chinese medicines that can regulate miRNA in the treatment of AD, so as to provide basis for revealing the pathogenesis relationship between miRNA and AD and provide ideas for further development of anti-AD traditional Chinese medicine.

Interaction between physical exercise and APOE gene polymorphism on cognitive function in older people

We aimed to present an overview of the literature regarding the interaction between physical exercise and APOE gene polymorphism on cognitive function, particularly in patients with Alzheimer's disease (AD). Firstly, this review focused on the effect of the physical exercise on cognitive function, regardless of APOE gene polymorphism. Some studies have shown that a high level of cardiorespiratory fitness is associated with less neuronal damage with an improvement in memory score tests whereas other studies failed to detect any association between physical exercise and cognitive improvement either in healthy individuals or patients with AD. Taken together, standardized protocols and more longitudinal studies are required to provide a better insight into the effects of physical exercise on cognitive function. Although there is no agreement in the literature regarding the effects of physical exercise on cognitive function, it is well established that it improves social interaction and the feeling of well-being, thereby positively contributing to the quality of life of the elderly. Regarding the influence of physical exercise on cognitive function in APOE ε4 allele carriers, the data trend shows that the carriers of allele ε4 for APOE gene were more responsive to the beneficial effects of physical exercise on cognitive function compared with non-carriers. Nevertheless, studies with larger sample sizes will provide more accuracy about this relationship.

Effect of active component compound of Epimedii Folium,Astragali Radix,and Puerariae Lobatae Radix on expression of ADAM17 in HT22 cells by mediating hepcidin / 中国中药杂志

Alzheimer's disease(AD) patients in China have been surging, and the resultant medical burden and care demand have a huge impact on the development of individuals, families, and the society. The active component compound of Epimedii Folium, Astragali Radix, and Puerariae Lobatae Radix(YHG) can regulate the expression of iron metabolism-related proteins to inhibit brain iron overload and relieve hypofunction of central nervous system in AD patients. Hepcidin is an important target regulating iron metabolism. This study investigated the effect of YHG on the expression of a disintegrin and metalloprotease-17(ADAM17), a key enzyme in the hydrolysis of β amyloid precursor protein(APP) in HT22 cells, by mediating hepcidin. To be specific, HT22 cells were cultured in vitro, followed by liposome-mediated siRNA transfection to silence the expression of hepcidin. Real-time PCR and Western blot were performed to examine the silencing result and the effect of YHG on hepcidin in AD cell model. HT22 cells were randomized into 7 groups: control group, Aβ25-35 induction(Aβ) group, hepcidin-siRNA(siRNA) group, Aβ25-35 + hepcidin-siRNA(Aβ + siRNA) group, Aβ25-35+YHG(Aβ+YHG) group, hepcidin-siRNA+YHG(siRNA+YHG) group, Aβ25-35+hepcidin-siRNA+YHG(Aβ+siRNA+YHG) group. The expression of ADAM17 mRNA in cells was detected by real-time PCR, and the expression of ADAM17 protein by immunofluorescence and Western blot. Immunofluorescence showed that the ADAM17 protein expression was lower in the Aβ group, siRNA group, and Aβ+siRNA group than in the control group(P<0.05) and the expression was lower in the Aβ+siRNA group(P<0.05) and higher in the Aβ+YHG group(P<0.05) than in the Aβ group. Moreover, the ADAM17 protein expression was lower in the Aβ+siRNA group(P<0.05) and higher in the siRNA+YHG group(P< 0.05) than in the siRNA group. The expression was higher in the Aβ+siRNA+YHG group than in the Aβ+siRNA group(P<0.05). The results of Western blot and real-time PCR were consistent with those of immunofluorescence. The experiment showed that YHG induced hepcidin to up-regulate the expression of ADAM17 in AD cell model and promote the activation of non-starch metabolic pathways, which might be the internal mechanism of YHG in preventing and treating AD.

MicroRNA-146a inhibition promotes total neurite outgrowth and suppresses cell apoptosis, inflammation, and STAT1/MYC pathway in PC12 and cortical neuron cellular Alzheimer's disease models

This study aimed to explore the effect of microRNA (miR)-146a inhibition on regulating cell apoptosis, total neurite outgrowth, inflammation, and STAT1/MYC pathway in Alzheimer's disease (AD). PC12 and cortical neuron cellular AD models were constructed by Aβ1-42 insult. For the former model, nerve growth factor (NGF) stimulation was previously conducted. miR-146a inhibitor and negative-control (NC) inhibitor were transfected into the two cellular AD models, and then cells were named miR-inhibitor group and NC-inhibitor group, respectively. After transfection, cell apoptosis, total neurite outgrowth, supernatant inflammation cytokines, and STAT1/MYC pathway were detected. miR-146a expression was similar between PC12 cellular AD model and control cells (NGF-stimulated PC12 cells), while miR-146a expression was increased in cortical neuron cellular AD model compared with control cells (rat embryo primary cortical neurons). In both PC12 and cortical neuron cellular AD models, miR-146a expression was reduced in miR-inhibitor group compared with NC-inhibitor group after transfection. Furthermore, cell apoptosis was attenuated, while total neurite outgrowth was elevated in miR-inhibitor group compared with NC-inhibitor group. As for supernatant inflammatory cytokines, tumor necrosis factor-α, interleukin (IL)-1β, IL-6, and IL-17 levels were lower in miR-inhibitor group than in NC-inhibitor group. Additionally, STAT1 and c-Myc mRNA and protein expressions were attenuated in miR-inhibitor group compared with NC-inhibitor group. In conclusion, miR-146a potentially represented a viable therapeutic target for AD.

Study design and baseline characteristics of a population-based prospective cohort study of dementia in Japan: the Japan Prospective Studies Collaboration for Aging and Dementia (JPSC-AD)

BACKGROUND@#The burden of dementia is growing rapidly and has become a medical and social problem in Japan. Prospective cohort studies have been considered an effective methodology to clarify the risk factors and the etiology of dementia. We aimed to perform a large-scale dementia cohort study to elucidate environmental and genetic risk factors for dementia, as well as their interaction.@*METHODS@#The Japan Prospective Studies Collaboration for Aging and Dementia (JPSC-AD) is a multisite, population-based prospective cohort study of dementia, which was designed to enroll approximately 10,000 community-dwelling residents aged 65 years or older from 8 sites in Japan and to follow them up prospectively for at least 5 years. Baseline exposure data, including lifestyles, medical information, diets, physical activities, blood pressure, cognitive function, blood test, brain magnetic resonance imaging (MRI), and DNA samples, were collected with a pre-specified protocol and standardized measurement methods. The primary outcome was the development of dementia and its subtypes. The diagnosis of dementia was adjudicated by an endpoint adjudication committee using standard criteria and clinical information according to the Diagnostic and Statistical Manual of Mental Disorders, 3rd Revised Edition. For brain MRI, three-dimensional acquisition of T1-weighted images was performed. Individual participant data were pooled for data analyses.@*RESULTS@#The baseline survey was conducted from 2016 to 2018. The follow-up surveys are ongoing. A total of 11,410 individuals aged 65 years or older participated in the study. The mean age was 74.4 years, and 41.9% were male. The prevalence of dementia at baseline was 8.5% in overall participants. However, it was 16.4% among three sites where additional home visit and/or nursing home visit surveys were performed. Approximately two-thirds of dementia cases at baseline were Alzheimer's disease.@*CONCLUSIONS@#The prospective cohort data from the JPSC-AD will provide valuable insights regarding the risk factors and etiology of dementia as well as for the development of predictive models and diagnostic markers for the future onset of dementia. The findings of this study will improve our understanding of dementia and provide helpful information to establish effective preventive strategies for dementia in Japan.

Investigation of chromosomal alterations in patients with Alzheimer's disease in the state of Amazonas, Brazil / Investigação de alterações cromossômicas em pacientes com doença de Alzheimer no estado do Amazonas, Brasil

ABSTRACT Alzheimer's disease (AD) has as its main characteristic the deterioration of cerebral functions. Its etiology is still complex and undefined despite the progress made in understanding its neurological, infectious, biochemical, genetic and cytogenetic mechanisms. Considering this, the aim of this study was to investigate the presence of chromosomal alterations in the peripheral blood lymphocytes, and to verify if there was a high frequency of these alterations in patients diagnosed with AD at the University Hospital GetúLio Vargas Outpatient Clinic Araújo Lima in Manaus, Amazonas, Brazil. Among the nine patients in the AD group, only one patient did not have metaphases with chromosomal alterations (2n = 46,XX), while eight patients with AD showed numerical chromosomal alterations, classified as X chromosome aneupLoidy (2n = 45,X) and double aneupLoidy (2n = 44,X,-X,-10; 2n = 44,X,-X,-13 and 2n = 44,X,-X,-21). In the control group, no chromosomal changes were found in the karyotypes of these individuals. Therefore, the karyotypes of patients with AD undergo chromosomal alterations at different levels. These findings are being described for the first time in the population of Amazonas, and they highlight the importance of the inclusion of cytogenetic investigations in the routine management of patients with AD.

RESUMO Doença de Alzheimer (DA) tem como principal característica a deterioração das funções cerebrais. Quanto a sua etiologia ainda é complexa e indefinida, apesar do progresso alcançado na compreensão de seus mecanismos neurológicos, infecciosos, bioquímicos, genéticos e citogenéticos. Considerando isto, nós investigamos a presença de alterações cromossômicas nos Linfócitos de sangue periférico e verificamos se há uma alta frequência dessas alterações em pacientes já diagnosticados com doença de Alzheimer no Hospital Universitário Getulio Vargas / Ambulatório Araújo Lima, Manaus / Amazonas / Brasil. Assim, dos 09 pacientes do grupo DA, somente 01 paciente não apresentou metáfases com alterações cromossômicas (2n = 46,XX) enquanto que 08 pacientes com DA apresentaram alterações cromossômicas numéricas, sendo classificadas como aneupLoidia do cromossomo X (2n = 45,X) e aneupLoidia dupLa (2n = 44,X,-X,-10; 2n = 44,X,-X,-13 e 2n = 44,X,-X,-21). No grupo controle, não foram encontradas aLterações cromossômicas nos cariótipos desses indivíduos. Estes achados para a popuLação do Amazonas/ BrasiL estão sendo descritos pela primeira vez. Os cariótipos de pacientes com DA sofrem aLterações cromossômicas em diferentes níveis e demonstraram a importância das investigações citogenéticas no manejo rotineiro de pacientes com DA.

Exploratory analysis of rare and novel variants in Mexican patients diagnosed with schizophrenia and dementia

Abstract Background Schizophrenia (SCZ) and dementia, often related, are two of the most common neuropsychiatric diseases; epidemiological studies have shown that SCZ patients present a 2-fold increased risk for dementia compared to non-schizophrenic individuals. We explored the presence of rare and novel damaging gene variants in patients diagnosed with late-onset dementia of Alzheimer’s type (DAT) or SCZ. Methods We included 7 DAT and 12 SCZ patients and performed high-depth targeted sequencing of 184 genes. Results We found novel and rare damaging variants in 18 genes in these Mexican patients. Carriers of these variants showed extreme phenotypes, including, treatment-resistant SCZ or cognitive decline. Furthermore, we found a variation on ABCC1 as a possible link between psychosis and cognitive impairment. Discussion As an exploratory analysis, we report some interesting variations that should be corroborated in larger sample size studies.

OxLDL plasma levels in patients with Alzheimer's disease / Níveis plasmáticos de LDL-ox em pacientes com doença de Alzheimer

ABSTRACT Objective: The objective of this study was to characterize the conventional lipid profile, oxLDL levels and ApoE polymorphism in patients with Alzheimer's disease (AD) and in elderly individuals without cognitive impairment. Methods: Eighty elderly individuals were selected and the levels of oxLDL were determined using the ELISA kit, and ApoE gene polymorphism was investigated using polymerase chain reaction-restriction fragment length polymorphism. Results: Significantly reduced levels of oxLDL were observed in patients with AD compared to the control group. A higher frequency of the ApoE ε4 allele was observed in patients with AD compared to controls. No difference was observed for total cholesterol, HDL-C, and LDL-C levels between the two groups, while triglyceride levels were higher in controls compared with patients with AD. Conclusion: The data analyzed together did not reveal significant differences in lipid profiles, including oxLDL levels. However, the importance of lipid changes in the genesis of the disease cannot be ruled out. Nevertheless, the ApoE ε4 allele was significantly more frequent in patients with Alzheimer's dementia in agreement with previous findings in the literature, but this genetic component did not change the levels of oxLDL.

RESUMO Objetivo: O objetivo deste estudo foi caracterizar o perfil lipídico convencional, os níveis de LDL-ox e o polimorfismo da ApoE em pacientes com doença de Alzheimer (DA) e em indivíduos idosos sem comprometimento cognitivo. Métodos: Foram selecionados oitenta indivíduos idosos. Os níveis de LDL-ox foram determinados usando o kit ELISA e a investigação do polimorfismo do gene da ApoE por PCR-RFLP. Resultados: Níveis significativamente reduzidos de LDL-ox foram observados em pacientes com DA comparado ao grupo controle. Uma maior frequência do alelo ε4 da ApoE foi observada nos pacientes com DA em relação aos controles. Nenhuma diferença foi observada para os níveis de colesterol total, HDL-C e LDL-C entre os dois grupos, enquanto níveis de triglicérides foram mais altos em controles comparados aos pacientes com DA. Conclusão: Os dados analisados em conjunto não revelaram diferenças significativas no perfil lipídico, incluindo os níveis de LDL-ox. No entanto, não se pode excluir a importância de alterações lipídicas na gênese da doença. Não obstante, o alelo ε4 da ApoE foi signicativamente mais frequente nos pacientes com demência de Alzheimer em concordância com achados prévios da literatura, mas esse componente genético não interferiu nos níveis de LDL-ox.

Alzheimer's disease and cytokine IL-10 gene polymorphisms: is there an association? / A doença de Alzheimer e os polimorfismos no gene da citocina IL-10: há alguma associação?

ABSTRACT Alzheimer's disease (AD) is the most common form of dementia. In the last 15 years, a new theory has proposed the autoimmune mechanism as a trigger for AD. Studies on the association between AD and inflammatory biomarkers have yielded controversial results. Interleukin-10 (IL-10), an anti-inflammatory mediator, has been pointed out as one of the main cytokines associated with the occurrence of AD. Moreover, treatment that increases IL-10 levels could be a potential therapy for AD, since this cytokine acts on amyloid and pro-inflammatory molecule reduction. Based on the current literature, this study reviews evidence regarding the role of IL-10 polymorphisms in the context of AD, which has been shown to be of paramount importance for attenuating neuroinflammation, cognitive dysfunction and neurodegeneration.

RESUMO A doença de Alzheimer (DA) é a forma mais comum de demência. Nos últimos 15 anos, uma nova teoria propõe um mecanismo autoimmune como o gatilho para a DA. Associações entre DA e biomarcadores inflamatórios têm sido registradas, contudo com resultados controversos. A interleucina-10 (IL-10), um mediador anti-inflamatório, tem sido apontada como uma das principais citocinas associadas com a ocorrência de DA. Além disso, os tratamentos que aumentam os níveis de IL-10 podem ser uma terapia potencial para DA, uma vez que esta citocina atua sobre a redução de substância amiloide e de moléculas pró-inflamatórias. Baseando-se em literaturas atuais, este estudo revisa evidências relacionadas com o papel da IL-10 e seus polimorfismos no contexto da DA, o qual se mostrou ser de fundamental importância para atenuar a neuroinflamação, a disfunção cognitiva e a neurodegeneração.

Associations of Cerebrovascular Metabolism Genotypes With Neuropsychiatric Symptoms and Age at Onset of Alzheimer's Disease Dementia

Objective: To study associations of cerebrovascular metabolism genotypes and haplotypes with age at Alzheimer’s disease dementia (AD) onset and with neuropsychiatric symptoms according to each dementia stage. Methods: Consecutive outpatients with late-onset AD were assessed for age at dementia onset and Neuropsychiatric Inventory scores according to Clinical Dementia Rating scores, apolipoprotein E gene (APOE) haplotypes, angiotensin-converting enzyme gene (ACE) variants rs1800764 and rs4291, low-density lipoprotein cholesterol receptor gene (LDLR) variants rs11669576 and rs5930, cholesteryl ester transfer protein gene (CETP) variants I422V and TaqIB, and liver X receptor beta gene (NR1H2) polymorphism rs2695121. Results: Considering 201 patients, only APOE-ɛ4 carriers had earlier dementia onset in multiple correlations, as well as less apathy, more delusions, and more aberrant motor behavior. Both ACE polymorphisms were associated with less intense frontally mediated behaviors. Regarding LDLR variants, carriers of the A allele of rs11669576 had less anxiety and more aberrant motor behavior, whereas carriers of the A allele of rs5930 had less delusions, less anxiety, more apathy, and more irritability. CETP variants that included G alleles of I422V and TaqIB were mostly associated with less intense frontally mediated behaviors, while severely impaired carriers of the T allele of rs2695121 had more anxiety and more aberrant motor behavior. Conclusion: Though only APOE haplotypes affected AD onset, cerebrovascular metabolism genotypes were associated with differences in several neuropsychiatric manifestations of AD.

Genetic variants associated with neurodegenerative Alzheimer disease in natural models

The use of transgenic models for the study of neurodegenerative diseases has made valuable contributions to the field. However, some important limitations, including protein overexpression and general systemic compensation for the missing genes, has caused researchers to seek natural models that show the main biomarkers of neurodegenerative diseases during aging. Here we review some of these models-most of them rodents, focusing especially on the genetic variations in biomarkers for Alzheimer diseases, in order to explain their relationships with variants associated with the occurrence of the disease in humans.

Independent and Interactive Influences of the APOE Genotype and Beta-Amyloid Burden on Cognitive Function in Mild Cognitive Impairment

This study aimed to investigate the independent and interactive influences of apolipoprotein E (APOE) epsilon4 and beta-amyloid (Abeta) on multiple cognitive domains in a large group of cognitively normal (CN) individuals and patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD). Participants were included if clinical and cognitive assessments, amyloid imaging, and APOE genotype were all available from the Alzheimer's Disease Neuroimaging Initiative database (CN = 324, MCI = 502, AD = 182). Individuals with one or two copies of epsilon4 were designated as APOE epsilon4 carriers (epsilon4+); individuals with no epsilon4 were designated as APOE epsilon4 non-carriers (epsilon4-). Based on mean florbetapir standard uptake value ratios, participants were classified as Abeta burden-positive (Abeta+) or Abeta burden-negative (Abeta-). In MCI, APOE epsilon4 effects were predominantly observed on frontal executive function, with epsilon4+ participants exhibiting poorer performances; Abeta positivity had no influence on this effect. Abeta effects were observed on global cognition, memory, and visuospatial ability, with Abeta+ participants exhibiting poorer performances. Measures of frontal executive function were not influenced by Abeta. Interactive effects of APOE epsilon4+ and Abeta were observed on global cognition and verbal recognition memory. Abeta, not APOE epsilon4+, influenced clinical severity and functional status. The influences of APOE epsilon4+ and Abeta on cognitive function were minimal in CN and AD. In conclusion, we provide further evidence of both independent and interactive influences of APOE epsilon4+ and Abeta on cognitive function in MCI, with APOE epsilon4+ and Abeta showing dissociable effects on executive and non-executive functions, respectively.

association between [8390G>A] single nucleotide polymorphism in APOE gene with Alzheimer's and Parkinson disease

Genetic susceptibility, is considered to be involved in neurodegenerative diseases such as Alzheimer's disease [AD] and Parkinson's disease [PD]. Despite the fact that many susceptibility genes for AD and PD have been considered, the most probable genetic risk factor which has been taken into consideration is Apolipoprotein E genotype located on chromosome 19q, APOE is the gene widely considered to be a susceptibility gene for neurodegenerative diseases. This study is to investigate the association of APOE polymorphism with AD and PD. In this case control study we examined association of an APOE gene polymorphism [rs121918398] with AD and PD in Iranian population. The study included 100 AD patients, 100 PD patients and 150 healthy volunteers. An informed consent was obtained from all participants. Genomic DNA was extracted from peripheral blood leukocyte. Genotypes were determined by PCR and restriction fragment length polymorphism [RFLP] by Hha1 restriction enzyme. Sequencing of PCR products was carried out by Fazabiotech Company according to Sanger method using ABI 3730XL Capillary Sequencer. Statistical analysis was performed using the MedCalc program. The prevalence of genotype frequencies of the APOE A/A, A/G, G/G were 16%, 34% and 50% in AD subjects, 14%, 32%, 54% in PD patients and in healthy volunteers were 15%, 39% and 96% respectively. Statistical analysis showed no significant difference between genotype frequencies of AD and those of control subjects [P < 0.05]. Moreover, according to statistical analysis, the genotype frequencies of APOE in PD subjects and control group did not significantly differ. This is the very first time that the association of this polymorphism [rs121918398] with AD is being reported nevertheless, there is no evidence that APOE variant is associated with PD. Accordingly, genotype alteration of A8390>G can't be related to AD. So, this polymorphism plays no pathogenic role in the PD and AD patients in Iranian population