BACKGROUND: Mild behavioral impairment (MBI) has been commonly reported in early Alzheimer's disease (AD) but rarely using biomarker-defined samples. It is also unclear whether genetic polymorphisms influence MBI in such individuals. We thus aimed to examine the association between the cognitive status of participants (amnestic mild cognitive impairment (aMCI-AD) vs cognitively normal (CN) older adults) and MBI severity. Within aMCI-AD, we further examined the association between APOE and BDNF risk genetic polymorphisms and MBI severity. METHODS: We included 62 aMCI-AD participants and 50 CN older adults from the Czech Brain Aging Study. The participants underwent neurological, comprehensive neuropsychological examination, APOE and BDNF genotyping, and magnetic resonance imaging. MBI was diagnosed with the Mild Behavioral Impairment Checklist (MBI-C), and the diagnosis was based on the MBI-C total score ≥ 7. Additionally, self-report instruments for anxiety (the Beck Anxiety Inventory) and depressive symptoms (the Geriatric Depression Scale-15) were administered. The participants were stratified based on the presence of at least one risk allele in genes for APOE (i.e., e4 carriers and non-carriers) and BDNF (i.e., Met carriers and non-carriers). We used linear regressions to examine the associations. RESULTS: MBI was present in 48.4% of the aMCI-AD individuals. Compared to the CN, aMCI-AD was associated with more affective, apathy, and impulse dyscontrol but not social inappropriateness or psychotic symptoms. Furthermore, aMCI-AD was related to more depressive but not anxiety symptoms on self-report measures. Within the aMCI-AD, there were no associations between APOE e4 and BDNF Met and MBI-C severity. However, a positive association between Met carriership and self-reported anxiety appeared. CONCLUSIONS: MBI is frequent in aMCI-AD and related to more severe affective, apathy, and impulse dyscontrol symptoms. APOE and BDNF polymorphisms were not associated with MBI severity separately; however, their combined effect warrants further investigation.

• MeSH
• Alzheimerova nemoc * diagnostické zobrazování   epidemiologie   genetika   MeSH
• apolipoproteiny E genetika   MeSH
• genotyp MeSH
• kognitivní dysfunkce * diagnostické zobrazování   epidemiologie   genetika   MeSH
• lidé MeSH
• mozkový neurotrofický faktor genetika   MeSH
• neuropsychologické testy MeSH
• polymorfismus genetický genetika   MeSH
• senioři MeSH
• Check Tag
• lidé MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: Apolipoprotein E (ApoE) ε4 genotype is the most prevalent risk factor for late-onset Alzheimer's Disease (AD). Although ApoE4 differs from its non-pathological ApoE3 isoform only by the C112R mutation, the molecular mechanism of its proteinopathy is unknown. METHODS: Here, we reveal the molecular mechanism of ApoE4 aggregation using a combination of experimental and computational techniques, including X-ray crystallography, site-directed mutagenesis, hydrogen-deuterium mass spectrometry (HDX-MS), static light scattering and molecular dynamics simulations. Treatment of ApoE ε3/ε3 and ε4/ε4 cerebral organoids with tramiprosate was used to compare the effect of tramiprosate on ApoE4 aggregation at the cellular level. RESULTS: We found that C112R substitution in ApoE4 induces long-distance (> 15 Å) conformational changes leading to the formation of a V-shaped dimeric unit that is geometrically different and more aggregation-prone than the ApoE3 structure. AD drug candidate tramiprosate and its metabolite 3-sulfopropanoic acid induce ApoE3-like conformational behavior in ApoE4 and reduce its aggregation propensity. Analysis of ApoE ε4/ε4 cerebral organoids treated with tramiprosate revealed its effect on cholesteryl esters, the storage products of excess cholesterol. CONCLUSIONS: Our results connect the ApoE4 structure with its aggregation propensity, providing a new druggable target for neurodegeneration and ageing.

• MeSH
• Alzheimerova nemoc * farmakoterapie   genetika   metabolismus   MeSH
• apolipoprotein E3 genetika   MeSH
• apolipoprotein E4 * genetika   metabolismus   MeSH
• apolipoproteiny E genetika   MeSH
• lidé MeSH
• mutace genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• apolipoproteiny E genetika   škodlivé účinky   MeSH
• epigeneze genetická fyziologie   genetika   MeSH
• geny * fyziologie   genetika   MeSH
• komplement - faktor H genetika   škodlivé účinky   MeSH
• lidé MeSH
• makulární degenerace * genetika   patofyziologie   MeSH
• retinální drúzy patologie   MeSH
• riziko MeSH
• životní styl MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• přehledy MeSH

Importance: The APOE ε2 and APOE ε4 alleles are the strongest protective and risk-increasing, respectively, genetic variants for late-onset Alzheimer disease (AD). However, the mechanisms linking APOE to AD-particularly the apoE protein's role in AD pathogenesis and how this is affected by APOE variants-remain poorly understood. Identifying missense variants in addition to APOE ε2 and APOE ε4 could provide critical new insights, but given the low frequency of additional missense variants, AD genetic cohorts have previously been too small to interrogate this question robustly. Objective: To determine whether rare missense variants on APOE are associated with AD risk. Design, Setting, and Participants: Association with case-control status was tested in a sequenced discovery sample (stage 1) and followed up in several microarray imputed cohorts as well as the UK Biobank whole-exome sequencing resource using a proxy-AD phenotype (stages 2 and 3). This study combined case-control, family-based, population-based, and longitudinal AD-related cohorts that recruited referred and volunteer participants. Stage 1 included 37 409 nonunique participants of European or admixed European ancestry, with 11 868 individuals with AD and 11 934 controls passing analysis inclusion criteria. In stages 2 and 3, 475 473 participants were considered across 8 cohorts, of which 84 513 individuals with AD and proxy-AD and 328 372 controls passed inclusion criteria. Selection criteria were cohort specific, and this study was performed a posteriori on individuals who were genotyped. Among the available genotypes, 76 195 were excluded. All data were retrieved between September 2015 and November 2021 and analyzed between April and November 2021. Main Outcomes and Measures: In primary analyses, the AD risk associated with each missense variant was estimated, as appropriate, with either linear mixed-model regression or logistic regression. In secondary analyses, associations were estimated with age at onset using linear mixed-model regression and risk of conversion to AD using competing-risk regression. Results: A total of 544 384 participants were analyzed in the primary case-control analysis; 312 476 (57.4%) were female, and the mean (SD; range) age was 64.9 (15.2; 40-110) years. Two missense variants were associated with a 2-fold to 3-fold decreased AD risk: APOE ε4 (R251G) (odds ratio, 0.44; 95% CI, 0.33-0.59; P = 4.7 × 10-8) and APOE ε3 (V236E) (odds ratio, 0.37; 95% CI, 0.25-0.56; P = 1.9 × 10-6). Additionally, the cumulative incidence of AD in carriers of these variants was found to grow more slowly with age compared with noncarriers. Conclusions and Relevance: In this genetic association study, a novel variant associated with AD was identified: R251G always coinherited with ε4 on the APOE gene, which mitigates the ε4-associated AD risk. The protective effect of the V236E variant, which is always coinherited with ε3 on the APOE gene, was also confirmed. The location of these variants confirms that the carboxyl-terminal portion of apoE plays an important role in AD pathogenesis. The large risk reductions reported here suggest that protein chemistry and functional assays of these variants should be pursued, as they have the potential to guide drug development targeting APOE.

• MeSH
• alely MeSH
• Alzheimerova nemoc * epidemiologie   genetika   MeSH
• apolipoprotein E2 genetika   MeSH
• apolipoprotein E4 genetika   MeSH
• apolipoproteiny E genetika   MeSH
• genotyp MeSH
• lidé MeSH
• věk při počátku nemoci MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

Familiární dysbetalipoproteinemie (FD) je autosomálně recesivně dědičným (vzácně dominantně) onemocněním, které podmiňuje mutace či polymorfizmus genu pro apolipoprotein E. Typickým genotypem je APOE2/E2, fenotypem pak smíšená dyslipidemie (DLP) manifestující se v kontextu dalších vyvolávajících metabolických či genetických faktorů. Jedná se o velmi aterogenní DLP, jež v konečném důsledku vede k předčasné manifestaci aterosklerózy, a to jak koronární, tak periferní. V ČR se předpokládá až 10 000 pacientů s touto diagnózou, bohužel jejich záchyt je dramaticky nižší. Na FD musíme pomýšlet vždy u pacientů s těžší smíšenou DLP s poměrem celkového cholesterolu a triglyceridů (T-C/TG) přibližně 2(1) : 1. Pacienty vhodné k dalšímu (zejména genetickému) vyšetření lze spolehlivě vybrat pomocí poměru nonHDL-cholesterolu a apolipoproteinu B. Definitivní diagnóza je pak stanovena pomocí genotypizace apolipoproteinu E, vzácněji ultracentrifugací lipoproteinů či elektroforeticky. Základ léčby představují důsledná režimová opatření; farmakoterapii volby pak kombinace statinu s fibrátem.

Familial dysbetalipoproteinemia (FD) is an autosomal recessive inherited (rarely dominant) disease that is caused by mutations or polymorphisms in the apolipoprotein E gene. The typical genotype is APOE2/E2, the phenotype is mixed dyslipidemia (DLP) manifesting in the context of other metabolic or genetic trigger factors. It is a very atherogenic dyslipidemia, which inevitably leads to the premature manifestation of atherosclerosis, both coronary and peripheral. Up to 10,000 patients with this diagnosis are expected in the Czech Republic, but unfortunately their detection is dramatically lower. FD must always be considered in patients with severe mixed DLP with a TC (total cholesterol)/TG (triglyceride) ratio of approximately 2(1) : 1. Patients suitable for further (especially genetic) examination can be reliably selected using the ratio of non- HDL-cholesterol/apolipoprotein B. The definitive diagnosis is then determined by genotyping apolipoprotein E, rarely by ultracentrifugation of lipoproteins or electrophoretically. The basis of treatment are lifestyle measures; pharmacotherapy of choice is a combination of statin with fibrate.

• MeSH
• apolipoproteiny E fyziologie   genetika   krev   MeSH
• hyperlipoproteinemie typ III * diagnóza   patofyziologie   terapie   MeSH
• lidé MeSH
• rizikové faktory kardiovaskulárních chorob MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH
• přehledy MeSH

IMPORTANCE: One characteristic histopathological event in Alzheimer disease (AD) is cerebral amyloid aggregation, which can be detected by biomarkers in cerebrospinal fluid (CSF) and on positron emission tomography (PET) scans. Prevalence estimates of amyloid pathology are important for health care planning and clinical trial design. OBJECTIVE: To estimate the prevalence of amyloid abnormality in persons with normal cognition, subjective cognitive decline, mild cognitive impairment, or clinical AD dementia and to examine the potential implications of cutoff methods, biomarker modality (CSF or PET), age, sex, APOE genotype, educational level, geographical region, and dementia severity for these estimates. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional, individual-participant pooled study included participants from 85 Amyloid Biomarker Study cohorts. Data collection was performed from January 1, 2013, to December 31, 2020. Participants had normal cognition, subjective cognitive decline, mild cognitive impairment, or clinical AD dementia. Normal cognition and subjective cognitive decline were defined by normal scores on cognitive tests, with the presence of cognitive complaints defining subjective cognitive decline. Mild cognitive impairment and clinical AD dementia were diagnosed according to published criteria. EXPOSURES: Alzheimer disease biomarkers detected on PET or in CSF. MAIN OUTCOMES AND MEASURES: Amyloid measurements were dichotomized as normal or abnormal using cohort-provided cutoffs for CSF or PET or by visual reading for PET. Adjusted data-driven cutoffs for abnormal amyloid were calculated using gaussian mixture modeling. Prevalence of amyloid abnormality was estimated according to age, sex, cognitive status, biomarker modality, APOE carrier status, educational level, geographical location, and dementia severity using generalized estimating equations. RESULTS: Among the 19 097 participants (mean [SD] age, 69.1 [9.8] years; 10 148 women [53.1%]) included, 10 139 (53.1%) underwent an amyloid PET scan and 8958 (46.9%) had an amyloid CSF measurement. Using cohort-provided cutoffs, amyloid abnormality prevalences were similar to 2015 estimates for individuals without dementia and were similar across PET- and CSF-based estimates (24%; 95% CI, 21%-28%) in participants with normal cognition, 27% (95% CI, 21%-33%) in participants with subjective cognitive decline, and 51% (95% CI, 46%-56%) in participants with mild cognitive impairment, whereas for clinical AD dementia the estimates were higher for PET than CSF (87% vs 79%; mean difference, 8%; 95% CI, 0%-16%; P = .04). Gaussian mixture modeling-based cutoffs for amyloid measures on PET scans were similar to cohort-provided cutoffs and were not adjusted. Adjusted CSF cutoffs resulted in a 10% higher amyloid abnormality prevalence than PET-based estimates in persons with normal cognition (mean difference, 9%; 95% CI, 3%-15%; P = .004), subjective cognitive decline (9%; 95% CI, 3%-15%; P = .005), and mild cognitive impairment (10%; 95% CI, 3%-17%; P = .004), whereas the estimates were comparable in persons with clinical AD dementia (mean difference, 4%; 95% CI, -2% to 9%; P = .18). CONCLUSIONS AND RELEVANCE: This study found that CSF-based estimates using adjusted data-driven cutoffs were up to 10% higher than PET-based estimates in people without dementia, whereas the results were similar among people with dementia. This finding suggests that preclinical and prodromal AD may be more prevalent than previously estimated, which has important implications for clinical trial recruitment strategies and health care planning policies.

• MeSH
• Alzheimerova nemoc * mozkomíšní mok   diagnostické zobrazování   epidemiologie   MeSH
• amyloidní beta-protein mozkomíšní mok   MeSH
• amyloidogenní proteiny MeSH
• amyloidóza * MeSH
• apolipoproteiny E genetika   MeSH
• biologické markery mozkomíšní mok   MeSH
• kognitivní dysfunkce * diagnostické zobrazování   epidemiologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• peptidové fragmenty mozkomíšní mok   MeSH
• pozitronová emisní tomografie MeSH
• prevalence MeSH
• proteiny tau mozkomíšní mok   MeSH
• průřezové studie MeSH
• senioři MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Genetic predispositions may influence geographical and interethnic differences in COVID-19 prevalence and mortality in affected populations. Of the many genes implicated in COVID-19 progression, a substantial number have no direct functional link on virus transfer/viability or on the host immune system. To address this knowledge deficit, a large number of in silico studies have recently been published. However, the results of these studies often contradict the findings of studies involving real patients. For example, the ACE2 has been shown to play an important role in regulating coronavirus entry into cells, but none of its variations have been directly associated with COVID-19 susceptibility or severity. Consistently was reported that increased risk of COVID-19 is associated with blood group A and with the APOE4 allele. Among other genes with potential impacts are the genes for CCR5, IL-10, CD14, TMPRSS2 and angiotensin-converting enzyme. Variants within the protein-coding genes OAS1 and LZTFL1 (transferred to the human genome from Neanderthals) are understood to be among the strongest predictors of disease severity. The intensive research efforts have helped to identify the genes and polymorphisms that contribute to SARS-CoV-2 infection and COVID-19 severity.

• MeSH
• ABO systém krevních skupin genetika   MeSH
• angiotensin konvertující enzym 2 genetika   MeSH
• apolipoproteiny E genetika   MeSH
• COVID-19 genetika   virologie   MeSH
• dědičnost MeSH
• fenotyp MeSH
• genetická predispozice k nemoci MeSH
• hodnocení rizik MeSH
• interakce hostitele a patogenu MeSH
• lidé MeSH
• polymorfismus genetický * MeSH
• progrese nemoci MeSH
• rizikové faktory MeSH
• SARS-CoV-2 patogenita   MeSH
• serinové endopeptidasy genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

BACKGROUND: Common polymorphisms within the apolipoprotein E (APOE) gene are suggested to be associated with the development of type 2 diabetes mellitus (T2DM), but the potential association with T2DM complications (nephropathy, neuropathy and retinopathy) remains unclear. We perform the case-control study to analyse the association between the APOE polymorphism and risk of T2DM and to analysed the potential relationship between the APOE and T2DM complications. METHODS AND RESULTS: APOE variants (rs429358 and rs7412) were genotyped by TaqMan assay in T2DM patients (N = 1274; N = 829 with complications including retinopathy, neuropathy and nephropathy status) and with PCR-RFLP in healthy nondiabetic controls (N = 2055). The comparison of subjects with genotypes associated with low plasma cholesterol (APOE2/E2 and APOE2/E3 carriers vs. others) did not show an association with T2DM (OR [95% CI] = 0.88 [0.71-1.08). The differences remained insignificant after adjusting for diabetes duration, sex and BMI. Carriers of at least one APOE4 allele (rs429358) are protected against T2DM related retinopathy (OR [95% CI] = 0.65 [0.42-0.99]. Protection against retinopathy is driven mostly by females (OR [95% CI] = 0.50 [0.25-0.99]); and remains significant (P = 0.044) after adjustment for diabetes duration and BMI. CONCLUSION: Common APOE polymorphism was not associated with T2DM in the Czech population. Yet, APOE4 allele revealed an association with retinopathy. In particular, female T2DM patients with at least one APOE4 allele exhibit lower prevalence of retinopathy in our study subjects.

• MeSH
• alely MeSH
• apolipoprotein E4 genetika   metabolismus   MeSH
• apolipoproteiny E genetika   metabolismus   MeSH
• diabetes mellitus 2. typu genetika   metabolismus   MeSH
• diabetická retinopatie genetika   metabolismus   MeSH
• dospělí MeSH
• frekvence genu genetika   MeSH
• genetická predispozice k nemoci genetika   MeSH
• genetické asociační studie MeSH
• genotyp MeSH
• jednonukleotidový polymorfismus MeSH
• lidé středního věku MeSH
• lidé MeSH
• rizikové faktory MeSH
• studie případů a kontrol MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH

Genetic discoveries of Alzheimer's disease are the drivers of our understanding, and together with polygenetic risk stratification can contribute towards planning of feasible and efficient preventive and curative clinical trials. We first perform a large genetic association study by merging all available case-control datasets and by-proxy study results (discovery n = 409,435 and validation size n = 58,190). Here, we add six variants associated with Alzheimer's disease risk (near APP, CHRNE, PRKD3/NDUFAF7, PLCG2 and two exonic variants in the SHARPIN gene). Assessment of the polygenic risk score and stratifying by APOE reveal a 4 to 5.5 years difference in median age at onset of Alzheimer's disease patients in APOE ɛ4 carriers. Because of this study, the underlying mechanisms of APP can be studied to refine the amyloid cascade and the polygenic risk score provides a tool to select individuals at high risk of Alzheimer's disease.

• MeSH
• Alzheimerova nemoc epidemiologie   genetika   patologie   MeSH
• amyloidový prekurzorový protein beta genetika   metabolismus   MeSH
• apolipoproteiny E genetika   MeSH
• celogenomová asociační studie MeSH
• datové soubory jako téma MeSH
• genetická predispozice k nemoci MeSH
• heterozygot MeSH
• hodnocení rizik metody   MeSH
• jednonukleotidový polymorfismus MeSH
• kohortové studie MeSH
• lidé středního věku MeSH
• lidé MeSH
• multifaktoriální dědičnost * MeSH
• následné studie MeSH
• rizikové faktory MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• studie případů a kontrol MeSH
• věk při počátku nemoci MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• validační studie MeSH

Alzheimerova nemoc je neurodegenerativní onemocnění, které vede k mozkové atrofii a ke vzniku demence. Jedná se o onemocnění s plynulým zhoršováním paměti a dalších kognitivních schopností. Etiologie prozatím není známá, ale existuje řada rizikových faktorů, které zvyšují pravděpodobnost vzniku onemocnění. Cílem naší přehledové práce je popsat klinicky podstatné rizikové faktory, které se na progresi Alzheimerovy nemoci podílejí, a faktory, které jsou jako rizikové zkoumány, ale dosud pro ně není dostatek důkazů. Obecně lze rizikové faktory rozdělit na ovlivnitelné (diabetes, hypertenze, obezita, dyslipidémie, kouření, užívání alkoholu, úrazy hlavy, deprese...) a neovlivnitelné (věk, pohlaví, výskyt onemocnění v rodině či výskyt polymorfismu ApoE4 v genu pro apolipoprotein E). Větší důraz je kladen na ovlivnitelné rizikové faktory, které poskytují prostor i pro další výzkumnou činnost.

Alzheimer´s disease is a neurodegenerative disorder that leads to brain atrophy and eventually dementia. It is an illness with continuous deterioration of memory and other cognitive functions. The etiology is not yet known, but there are a number of risk factors that increase the likelihood of developing the disease. The aim of our review is to describe the clinically relevant risk factors involved in the progression of Alzheimer´s disease and those factors that are being considered, but still with insufficient evidence for them. In general, risk factors can be divided into modifiable (diabetes, hyper-tension, obesity, dyslipidemia, smoking, alcohol use, head trauma, depression.) and non-modifiable (age, sex, heredity or apolipoprotein E gene variants). Greater emphasis is placed on modifiable risk factors that provide scope for further research activities.

• MeSH
• Alzheimerova nemoc * etiologie   MeSH
• apolipoproteiny E genetika   škodlivé účinky   MeSH
• cerebrovaskulární poruchy komplikace   MeSH
• deprese komplikace   MeSH
• diabetes mellitus 2. typu komplikace   patofyziologie   MeSH
• hypertenze komplikace   MeSH
• kardiovaskulární nemoci komplikace   MeSH
• kognitivní poruchy etiologie   MeSH
• kouření cigaret škodlivé účinky   MeSH
• kraniocerebrální traumata komplikace   MeSH
• lidé MeSH
• metabolický syndrom komplikace   MeSH
• obezita klasifikace   komplikace   MeSH
• pití alkoholu škodlivé účinky   MeSH
• podvýživa komplikace   MeSH
• pohybová aktivita fyziologie   MeSH
• poměr pasu a boků MeSH
• pooperační delirium komplikace   MeSH
• rizikové faktory MeSH
• sociální izolace MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH
• přehledy MeSH