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1.
bioRxiv ; 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38585830

RESUMEN

A lack of empathy, and particularly its affective components, is a core symptom of behavioural variant frontotemporal dementia (bvFTD). Visual exposure to images of a needle pricking a hand (pain condition) and Q-tips touching a hand (control condition) is an established functional magnetic resonance imaging (fMRI) paradigm used to investigate empathy for pain (EFP; pain condition minus control condition). EFP has been associated with increased blood oxygen level dependent (BOLD) signal in regions known to become atrophic in the early stages in bvFTD, including the anterior insula and the anterior cingulate. We therefore hypothesized that patients with bvFTD would display altered empathy processing in the EFP paradigm. Here we examined empathy processing using the EFP paradigm in 28 patients with bvFTD and 28 sex and age matched controls. Participants underwent structural MRI, task-based and resting-state fMRI. The Interpersonal Reactivity Index (IRI) was used as a measure of different facets of empathic function outside the scanner. The EFP paradigm was analysed at a whole brain level and using two regions-of-interest approaches, one based on a metanalysis of affective perceptual empathy versus cognitive evaluative empathy and one based on the controls activation pattern. In controls, EFP was linked to an expected increase of BOLD signal that displayed an overlap with the pattern of atrophy in the bvFTD patients (insula and anterior cingulate). Additional regions with increased signal were the supramarginal gyrus and the occipital cortex. These latter regions were the only ones that displayed increased BOLD signal in bvFTD patients. BOLD signal increase under the affective perceptual empathy but not the cognitive evaluative empathy region of interest was significantly greater in controls than in bvFTD patients. The controls rating on their empathic concern subscale of the IRI was significantly correlated with the BOLD signal in the EFP paradigm, as were an informants ratings of the patients empathic concern subscale. This correlation was not observed on other subscales of the IRI or when using the patient's self-ratings. Finally, controls and patients showed different connectivity patterns in empathy related networks during resting-state fMRI, mainly in nodes overlapping the ventral attention network. Our results indicate that reduced neural activity in regions typically affected by pathology in bvFTD is associated with reduced empathy processing, and a predictor of patients capacity to experience affective empathy.

2.
Alzheimers Res Ther ; 15(1): 161, 2023 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-37779209

RESUMEN

BACKGROUND: Chronic stress and depression are potential risk factors for mild cognitive impairment and dementia, including Alzheimer disease. The aim was to investigate whether any such risk is additive. METHODS: Cohort study including 1 362 548 people (665 997 women, 696 551 men) with records in the Region Stockholm administrative healthcare database (VAL). Exposure was a recorded ICD-10 diagnosis of chronic stress, depression, or both, recorded in 2012 or 2013. Outcome was a diagnosis of Alzheimer disease, other dementia, or mild cognitive impairment recorded from 2014 through 2022. Odds ratios with 99% confidence intervals (CI) adjusted for age, sex, neighborhood socioeconomic status, diabetes, and cardiovascular disorders were calculated. RESULTS: During the exposure period, 4 346 patients were diagnosed with chronic stress, 40 101 with depression, and 1 898 with both. The average age at baseline was around 40 years in all groups. In the fully adjusted model, the odds ratio of Alzheimer disease was 2.45 (99% CI 1.22-4.91) in patients with chronic stress, 2.32 (99% CI 1.85-2.90) in patients with depression, and 4.00 (99% CI 1.67-9.58) in patients with chronic stress and depression. The odds ratio of mild cognitive impairment was 1.87 (99% CI 1.20-2.91) in patients with chronic stress, 2.85 (99% CI 2.53-3.22) in patients with depression, and 3.87 (99% CI 2.39-6.27) in patients with both. When other dementia was analyzed, the odds ratio was significant only in patients with depression, 2.39 (99% CI 1.92-2.96). CONCLUSIONS: Documented chronic stress increased the risk of mild cognitive impairment and Alzheimer disease. The same was seen with depression. The novel finding is the potential additive effect of chronic stress to depression, on risk of MCI and AD.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Masculino , Humanos , Femenino , Adulto , Adolescente , Adulto Joven , Persona de Mediana Edad , Anciano , Estudios de Cohortes , Enfermedad de Alzheimer/diagnóstico , Depresión/epidemiología , Disfunción Cognitiva/diagnóstico , Factores de Riesgo
3.
Brain Commun ; 5(5): fcad228, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37680670

RESUMEN

Alzheimer's disease is a multifactorial disorder with large heterogeneity. Comorbidities such as hypertension, hypercholesterolaemia and diabetes are known contributors to disease progression. However, less is known about their mechanistic contribution to Alzheimer's pathology and neurodegeneration. The aim of this study was to investigate the relationship of several biomarkers related to risk mechanisms in Alzheimer's disease with the well-established Alzheimer's disease markers in a memory clinic population without common comorbidities. We investigated 13 molecular markers representing key mechanisms underlying Alzheimer's disease pathogenesis in CSF from memory clinic patients without diagnosed hypertension, hypercholesterolaemia or diabetes nor other neurodegenerative disorders. An analysis of covariance was used to compare biomarker levels between clinical groups. Associations were analysed by linear regression. Two-step cluster analysis was used to determine patient clusters. Two key markers were analysed by immunofluorescence staining in the hippocampus of non-demented control and Alzheimer's disease individuals. CSF samples from a total of 90 participants were included in this study: 30 from patients with subjective cognitive decline (age 62.4 ± 4.38, female 60%), 30 with mild cognitive impairment (age 65.6 ± 7.48, female 50%) and 30 with Alzheimer's disease (age 68.2 ± 7.86, female 50%). Angiotensinogen, thioredoxin-1 and interleukin-15 had the most prominent associations with Alzheimer's disease pathology, synaptic and axonal damage markers. Synaptosomal-associated protein 25 kDa and neurofilament light chain were increased in mild cognitive impairment and Alzheimer's disease patients. Grouping biomarkers by biological function showed that inflammatory and survival components were associated with Alzheimer's disease pathology, synaptic dysfunction and axonal damage. Moreover, a vascular/metabolic component was associated with synaptic dysfunction. In the data-driven analysis, two patient clusters were identified: Cluster 1 had increased CSF markers of oxidative stress, vascular pathology and neuroinflammation and was characterized by elevated synaptic and axonal damage, compared with Cluster 2. Clinical groups were evenly distributed between the clusters. An analysis of post-mortem hippocampal tissue showed that compared with non-demented controls, angiotensinogen staining was higher in Alzheimer's disease and co-localized with phosphorylated-tau. The identification of biomarker-driven endophenotypes in cognitive disorder patients further highlights the biological heterogeneity of Alzheimer's disease and the importance of tailored prevention and treatment strategies.

5.
Mol Psychiatry ; 28(3): 1272-1283, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36447011

RESUMEN

Recent mechanistic and structural studies have challenged the classical tauopathy classification approach and revealed the complexity and heterogeneity of tau pathology in Alzheimer's disease (AD) and primary tauopathies such as corticobasal degeneration (CBD) and progressive supranuclear palsy (PSP), progressing beyond distinct tau isoforms. In this multi-tau tracer study, we focused on the new second-generation tau PET tracers PI2620, MK6240 and RO948 to investigate this tau complexity in AD, CBD, and PSP brains using post-mortem radioligand binding studies and autoradiography of large and small frozen brain sections. Saturation binding studies indicated multiple binding sites for 3H-PI2620 in AD, CBD and PSP brains with different binding affinities (Kd ranging from 0.2 to 0.7 nM) and binding site densities (following the order: BmaxAD > BmaxCBD > BmaxPSP). Competitive binding studies complemented these findings, demonstrating the presence of two binding sites [super-high affinity (SHA): IC50(1) = 8.1 pM; and high affinity (HA): IC50(2) = 4.9 nM] in AD brains. Regional binding distribution studies showed that 3H-PI2620 could discriminate between AD (n = 6) and control cases (n = 9), especially in frontal cortex and temporal cortex tissue (p < 0.001) as well as in the hippocampal region (p = 0.02). 3H-PI2620, 3H-MK6240 and 3H-RO948 displayed similar binding behaviour in AD brains (in both homogenate competitive studies and one large frozen hemispherical brain section autoradiography studies) in terms of binding affinities, number of sites and regional patterns. Our small section autoradiography studies in the frontal cortex of CBD (n = 3) and PSP brains (n = 2) showed high specificity for 3H-PI2620 but not for 3H-MK6240 or 3H-RO948. Our findings clearly demonstrate different binding properties among the second-generation tau PET tracers, which may assist in further understanding of tau heterogeneity in AD versus non-AD tauopathies and suggests potential for development of pure selective 4R tau PET tracers.


Asunto(s)
Enfermedad de Alzheimer , Degeneración Corticobasal , Parálisis Supranuclear Progresiva , Tauopatías , Humanos , Enfermedad de Alzheimer/metabolismo , Parálisis Supranuclear Progresiva/metabolismo , Parálisis Supranuclear Progresiva/patología , Proteínas tau/metabolismo , Tauopatías/metabolismo , Encéfalo/metabolismo
6.
J Alzheimers Dis ; 89(3): 825-834, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35938253

RESUMEN

BACKGROUND: Several studies have examined association between vitamin D levels in serum and cognition, but little is known of vitamin D levels in cerebrospinal fluid (CSF) and association with Alzheimer's disease (AD). OBJECTIVE: In this cross-sectional, explorative study we investigated possible associations of vitamin D in CSF with biomarkers for AD, amyloid-ß, tau protein/phosphorylated tau protein in CSF, and with the cytokines IL-6, IL-8, and TNF-α in CSF in patients with cognitive impairment and cognitively healthy controls. METHODS: We included 100 outpatients ≥65 years referred for assessment of cognitive impairment and 76 age- and sex-matched cognitively healthy controls. Levels of 25-hydroxyvitamin D (25(OH)D), amyloid-ß, tau protein and phosphorylated tau protein, as well as IL-6, IL-8, and TNF-α, were analyzed in CSF in both groups. RESULTS: Higher levels of 25(OH)D in CSF in all groups together were associated with lower levels of tau protein (p = 0.01) and phosphorylated tau protein (p = 0.005). We found no association between 25(OH)D levels in CSF and pathological levels of amyloid-ß in CSF nor levels of IL-6 or TNF-α in CSF. Higher levels of 25(OH)D in CSF were associated with higher levels of IL-8 in CSF (p = 0.002). However, vitamin D explained only 6% of variance in IL-8. There was no significant difference between the patient groups and the control group regarding the association between 25(OH)D in CSF and any of the three cytokines in CSF. CONCLUSION: Participants with higher CSF levels of 25(OH)D exhibited reduced CSF levels of tau protein and phosphorylated tau protein.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Disfunción Cognitiva/líquido cefalorraquídeo , Estudios Transversales , Citocinas , Humanos , Interleucina-6 , Interleucina-8 , Fragmentos de Péptidos/líquido cefalorraquídeo , Factor de Necrosis Tumoral alfa , Vitamina D , Vitaminas , Proteínas tau/líquido cefalorraquídeo
7.
Front Aging Neurosci ; 14: 878303, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35663567

RESUMEN

Alzheimer's disease (AD) is characterized by impaired protein homeostasis leading to amyloid-ß peptide (Aß) amyloidosis. Amyloid precursor protein (APP) knock-in mice exhibit robust Aß pathology, providing possibilities to determine its effect on protein homeostasis including autophagy. Here we compared human AD postmortem brain tissue with brains from two different types of App knock-in mice, App NL-F and App NL-G-F mice, exhibiting AD-like pathology. In AD postmortem brains, p62 levels are increased and p62-positive staining is detected in neurons, including potential axonal beadings, as well as in the vasculature and in corpora amylacea. Interestingly, p62 is also increased in the neurons in 12-month-old App NL-G-F mice. In brain homogenates from 12-month-old App NL-G-F mice, both p62 and light chain 3 (LC3)-II levels are increased as compared to wildtype (WT) mice, indicating inhibited autophagy. Double immunostaining for LC3 and Aß revealed LC3-positive puncta in hippocampus of 24-month-old App NL-F mice around the Aß plaques which was subsequently identified by electron microscopy imaging as an accumulation of autophagic vacuoles in dystrophic neurites around the Aß plaques. Taken together, autophagy is impaired in App knock-in mice upon increased Aß pathology, indicating that App knock-in mouse models provide a platform for understanding the correlation between Aß and autophagy.

8.
J Alzheimers Dis ; 86(3): 1459-1470, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35213378

RESUMEN

BACKGROUND: Neuroinflammation is a central component of Alzheimer's disease (AD) and correlates closely with amyloid pathology. Markers of inflammation such as cytokines, and amyloidogenic aggregates, so-called nanoplaques, are both promising biomarker candidates for AD. We have previously shown that there is a relationship between the levels of nanoplaques and cytokines in cerebrospinal fluid, but it is unknown whether this association extends to serum. OBJECTIVE: Investigate in a naturalistic memory clinic cohort whether the associations between nanoplaques and cytokines in the cerebrospinal fluid extends to serum. METHODS: We collected serum from 49 patients assessed for cognitive complaints at the Oslo University Hospital Memory Clinic (15 with clinical AD). We assessed the levels of serum nanoplaques with the novel Thioflavin-T fluorescence correlation spectroscopy (ThT-FCS) assay. Serum levels of nine cytokines (eotaxin-1, granulocyte colony-stimulating factor [G-CSF], interleukin [IL]-6, IL-7, IL-8, monocyte chemoattractant protein-1 (MCP-1), gamma induced protein 10 (IP-10), macrophage inflammatory protein [MIP]-1α, and MIP-1ß) were quantified with a multiplex assay and read on a Luminex IS 200 instrument. RESULTS: Serum nanoplaques were not increased in clinical AD patients compared to non-AD memory clinic patients and nanoplaques were not associated with any cytokines. The cytokines IL-8 and G-CSF were increased in patients with clinical AD compared to non-AD patients. CONCLUSION: In this small pilot study, serum nanoplaques were not associated with serum cytokines. Nanoplaque levels could not be used to separate clinical AD patients from non-AD patients in this unselected memory clinic cohort.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Alzheimer/patología , Biomarcadores/líquido cefalorraquídeo , Citocinas , Factor Estimulante de Colonias de Granulocitos , Humanos , Interleucina-6 , Interleucina-8 , Proyectos Piloto
9.
J Alzheimers Dis ; 86(3): 1301-1314, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35180126

RESUMEN

BACKGROUND: Vitamin D insufficiency has been suggested as a dementia risk factor. OBJECTIVE: In this cross-sectional, explorative study we investigated whether levels of vitamin D in cerebrospinal fluid (CSF) are lower in patients with positive biomarkers of Alzheimer's disease (AD) compared to cognitively healthy controls and whether polymorphisms of the vitamin D receptor (VDR) gene, FokI, BsmI, ApaI, and TaqI, are associated with levels of vitamin D in CSF and cognition. METHODS: We included 100 patients≥65 years assessed for cognitive impairment and 76 cognitively healthy controls. Levels of 25-hydroxyvitamin D (25(OH)D) in both serum and CSF, and VDR polymorphisms were analyzed. RESULTS: The mean level of 25(OH)D in serum was 78.6 (SD 28.9) nmol/l. While serum levels of 25(OH)D were not significantly different between the groups, CSF levels of 25(OH)D were significantly lower in patients with positive AD core biomarkers (p = 0.001) compared to patients without such biomarkers. Individuals with the BsmI major homozygote genotype had significantly lower results on a 10-word delayed recall test (p = 0.044) and verbal fluency test (p = 0.013), and individuals with the TaqI major homozygote genotype had significantly lower results on a verbal fluency test (p = 0.030) compared to individuals with the corresponding minor homozygote genotype. CONCLUSION: Patients with positive AD core biomarkers have low CSF levels of 25(OH)D, despite sufficient serum levels. CSF levels of 25(OH)D do not seem to be affected by any of the four VDR gene polymorphisms. TaqI and BsmI major homozygote genotypes might be at increased risk for development of cognitive decline.


Asunto(s)
Enfermedad de Alzheimer , Vitamina D , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/líquido cefalorraquídeo , Enfermedad de Alzheimer/genética , Biomarcadores/sangre , Biomarcadores/líquido cefalorraquídeo , Estudios de Casos y Controles , Estudios Transversales , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Polimorfismo de Nucleótido Simple , Vitamina D/sangre , Vitamina D/líquido cefalorraquídeo , Vitaminas/sangre , Vitaminas/líquido cefalorraquídeo
10.
Front Aging Neurosci ; 13: 735334, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34867272

RESUMEN

Novel insights on proteins involved in Alzheimer's disease (AD) are needed. Since multiple cell types and matrix components are altered in AD, bulk analysis of brain tissue maybe difficult to interpret. In the current study, we isolated pyramidal cells from the cornu ammonis 1 (CA1) region of the hippocampus from five AD and five neurologically healthy donors using laser capture microdissection (LCM). The samples were analyzed by proteomics using 18O-labeled internal standard and nano-high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) for relative quantification. Fold change between AD and control was calculated for the proteins that were identified in at least two individual proteomes from each group. From the 10 cases analyzed, 62 proteins were identified in at least two AD cases and two control cases. Creatine kinase B-type (CKB), 14-3-3-γ, and heat shock cognate 71 (Hsc71), which have not been extensively studied in the context of the human AD brain previously, were selected for further studies by immunohistochemistry (IHC). In hippocampus, semi-quantitative measures of IHC staining of the three proteins confirmed the findings from our proteomic analysis. Studies of the same proteins in the frontal cortex revealed that the alterations remained for CKB and 14-3-3-γ but not for Hsc71. Protein upregulation in CA1 neurons of final stage AD is either a result of detrimental, pathological effects, or from cell-specific protective response mechanisms in surviving neurons. Based on previous findings from experimental studies, CKB and Hsc71 likely exhibit protective effects, whereas 14-3-3-γ may represent a detrimental pathway. These new players could reflect pathways of importance for the development of new therapeutic strategies.

11.
BMC Geriatr ; 21(1): 568, 2021 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-34663229

RESUMEN

BACKGROUND: Delirium is common in older hospitalized patients. It has serious consequences e.g., poor health outcomes, mortality and increased costs. Despite that, many cases are undetected. Early detection of delirium is important in improving outcomes and use of assessment tools improves detection rates. The 4AT is a brief screening tool for delirium detection, which has not previously been translated into Swedish. The study aim was to evaluate diagnostic accuracy and clinical applicability of a Swedish version of the screening tool 4AT for delirium detection. METHOD: This diagnostic test accuracy study used a quantitative and a qualitative approach and evaluated the patients' and the health care professionals' experiences of the tool. Study included 200 patients ≥65 years from a university hospital and a county hospital in two Swedish regions. Medical specialties were geriatric stroke/neurology, geriatric multimorbidity, severe cognitive impairment, orthopaedic, and urology. The translated 4AT was tested against the reference standard DSM-IV-TR criteria, based on the Organic Brain Syndrome scale and patient records. The 4AT was assessed simultaneously and independently by two assessors. Additionally, data was collected through patient record reviews, and questions about applicability to the patients (n = 200) and the assessors (n = 37). Statistical analyses, and qualitative content analyses were conducted. RESULTS: By reference standard 18% had delirium, and by 4AT 19%. The overall percent agreement was 88%, AUROC 0.808, sensitivity 0.70 (95% CI 0.51-0.84) and specificity 0.92 (95% CI 0.87-0.96). In the ward for severe cognitive impairment (n = 63) the 4AT was less sensitive and less specific. In the other wards (n = 132) sensitivity was 0.77 (95% CI 0.50-0.93), specificity 0.93 (95% CI 0.87-0.97), and AUROC 0.848. Interrater reliability (Kappa) was 0.918, p = < 0.001 (n = 144). The 4AT was well tolerated by patients, easy to use for health care professionals, and took a few minutes to conduct. CONCLUSION: The Swedish version of 4AT is an accurate and applicable tool to use in clinical practice for detecting delirium in hospitalized patients across different medical specialities, and to use by different professionals and levels of seniority. To improve patient outcomes, we recommend the 4AT to be incorporated in clinical practice in health care settings in Sweden.


Asunto(s)
Delirio , Anciano , Delirio/diagnóstico , Delirio/epidemiología , Evaluación Geriátrica , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Suecia/epidemiología
12.
BMC Neurol ; 21(1): 303, 2021 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-34362322

RESUMEN

BACKGROUND: Plasmacytomas are rare tumors comprised of neoplastic monoclonal plasma cells and can be found anywhere in the body. Plasmacytomas that involve the nervous system can give rise to diffuse symptoms depending on their location. Patients with confusion or dementia might be difficult to neurologically assess in an acute setting and the subtle symptoms of neurological pathology caused by rare malignancies might go undiagnosed. CASE PRESENTATION: The patient is an 80 year old man presenting to the ER with walking difficulties, pain, and confusion. He underwent neurological evaluation for dementia and was eventually diagnosed with possible Alzheimer's disease and a malignant plasmacytoma causing spinal cord compression. His CSF sample showed normal amyloid rate and very low Aß. Following rehabilitation and oncological treatment, his walking ability and confusion improved. CONCLUSION: This case is unique as we demonstrate that spinal cord compression by plasmacytoma can lead to abnormal CSF levels of several known pathology markers for Alzheimer's disease and neuronal damage. We suggest that highly divergent amyloid CSF levels could be indicative of spinal pathologies affecting CSF circulation. We also suggest closer assessment of elderly confusion patients in ER settings by consultants specialized in neurological disorders.


Asunto(s)
Disfunción Cognitiva , Plasmacitoma , Compresión de la Médula Espinal , Anciano de 80 o más Años , Enfermedad de Alzheimer , Biomarcadores , Humanos , Masculino , Plasmacitoma/complicaciones , Compresión de la Médula Espinal/diagnóstico por imagen , Compresión de la Médula Espinal/etiología
13.
Transl Neurodegener ; 10(1): 18, 2021 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-34099032

RESUMEN

BACKGROUND: The aggregation of amyloid ß (Aß) is central in the pathogenesis of Alzheimer's disease (AD). Recently it has been shown that specifically, larger, Thioflavin T-binding Aß aggregates are associated with increased neuroinflammation and cytokine release. This study was aimed to quantify fibrillary amyloid aggregates, so-called nanoplaques, and investigate their relationship with cytokines in the cerebrospinal fluid (CSF). METHODS: CSF was collected from 111 patients assessed for cognitive complaints at the Oslo University Hospital Memory Clinic. The patients were grouped based on their amyloid status. The CSF nanoplaque concentration was quantified with the Thioflavin T-fluorescence correlation spectroscopy (ThT-FCS) assay. The levels of nine cytokines (eotaxin-1, granulocyte stimulating factor, interleukin [IL]-6, IL-7, IL-8, monocyte chemoattractant protein-1, gamma-induced protein 10, macrophage inflammatory protein [MIP]-1α, and MIP-1ß) were quantified with a magnetic bead-based multiplex assay and read on a Luminex IS 200 instrument. RESULTS: There were 49 amyloid-negative and 62 amyloid-positive patients in the cohort; none of the cytokines differed significantly between the amyloid groups. The increased nanoplaque levels were associated with levels of MIP-1ß below the lower limit of quantification, and with decreased levels of MIP-1α and IL-8. The associations remained significant when adjusted for age, sex, cognitive function, apolipoprotein ε4 status and CSF core biomarker levels. CONCLUSION: The cytokine levels were not associated with amyloid status in this cohort. The nanoplaque levels were negatively associated with MIP-1ß, MIP-1α and IL-8, which is in line with recent findings suggesting that the upregulation of some cytokine markers has a protective role and is negatively associated with AD progression.


Asunto(s)
Enfermedad de Alzheimer/líquido cefalorraquídeo , Citocinas/líquido cefalorraquídeo , Placa Amiloide/líquido cefalorraquídeo , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/psicología , Péptidos beta-Amiloides/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Estudios de Cohortes , Femenino , Humanos , Masculino , Pruebas de Estado Mental y Demencia , Persona de Mediana Edad , Nanopartículas , Espectrometría de Fluorescencia
14.
Mol Psychiatry ; 26(10): 5609-5619, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-32581318

RESUMEN

Autosomal-dominant Alzheimer's disease (ADAD) may be associated with atypical amyloid beta deposits in the brain. In vivo amyloid imaging using 11C-Pittsburgh compound B (PiB) tracer has shown differences in binding between brains from ADAD and sporadic Alzheimer's disease (sAD) patients. To gain further insight into the various pathological characteristics of these genetic variants, we performed large frozen hemisphere autoradiography and brain homogenate binding assays with 3H-PiB, 3H-MK6240-3H-THK5117, and 3H-deprenyl for detection of amyloid fibrils, tau depositions, and activated astrocytes, respectively, in two AßPParc mutation carriers, one PSEN1ΔE9 mutation carrier, and three sAD cases. The results were compared with Abeta 40, Abeta 42, AT8, and GFAP immunostaining, respectively, as well as with Congo red and Bielschowsky. PiB showed a very low binding in AßPParc. A high binding was observed in PSEN1ΔE9 and in sAD tissues but with different binding patterns. Comparable 3H-THK5117 and 3H-deprenyl brain homogenate binding was observed for AßPParc, PSEN1ΔE9, and sAD, respectively. Some differences were observed between 3H-MK6240 and 3H-THK5117 in ADAD. A positive correlation between 3H-deprenyl and 3H-THK5117 binding was observed in AßPParc, while no such correlation was found in PSEN1ΔE9 and sAD. Our study demonstrates differences in the properties of the amyloid plaques between two genetic variants of AD and sAD. Despite the lack of measurable amyloid fibrils by PiB in the AßPParc cases, high regional tau and astrocyte binding was observed. The lack of correlation between 3H-deprenyl and 3H-THK5117 binding in PSEN1ΔE9 and sAD in contrast of the positive correlation observed in the AßPParc cases suggest differences in the pathological cascade between variants of AD that warrant further exploration in vivo.


Asunto(s)
Enfermedad de Alzheimer , Astrocitos , Enfermedad de Alzheimer/genética , Amiloide , Péptidos beta-Amiloides/metabolismo , Compuestos de Anilina , Astrocitos/metabolismo , Encéfalo/metabolismo , Humanos , Placa Amiloide , Tomografía de Emisión de Positrones , Presenilina-1 , Proteínas tau/genética , Proteínas tau/metabolismo
15.
J Alzheimers Dis ; 79(1): 311-321, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33252081

RESUMEN

BACKGROUND: Allele ɛ4 of the apolipoprotein (APOE∈4) gene is the strongest known genetic risk factor for late-onset sporadic Alzheimer's disease. A possible relationship between vitamin D and APOE is not yet clear. OBJECTIVE: In this exploratory, cross-sectional study, we examined the association between serum levels of 25-hydroxyvitamin D [25(OH)D] and brain volumes and the associations of both serum levels of 25(OH)D and APOE polymorphism to brain volumes in 127 persons (mean age 66 years) with cognitive symptoms. METHODS: All subjects were examined with fully automated software for MRI volumetry, NeuroQuant. RESULTS: After adjustment for relevant covariates, higher serum 25(OH)D levels were associated with greater volumes of cortical gray matter on both left (p = 0.02) and right (p = 0.04) sides. When both 25(OH)D levels and APOE genotype were used as the main covariates, no significant associations were found between vitamin D level and brain volume in any of the 11 brain regions. In adjusted models, only homozygous but not heterozygous APOE∈4 allele carriers had significantly larger inferior lateral ventricles (p = 0.003) and smaller hippocampal volume (p = 0.035) than those without ɛ4. Homozygous APOE∈4 carriers also had significantly higher vitamin D levels (p = 0.009) compared to persons without the APOE∈4 allele. CONCLUSION: Higher vitamin D levels might have a preserving effect on cortical grey matter volume.


Asunto(s)
Enfermedad de Alzheimer/sangre , Apolipoproteína E4/genética , Encéfalo/diagnóstico por imagen , Disfunción Cognitiva/sangre , Vitamina D/análogos & derivados , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/genética , Encéfalo/patología , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/genética , Autoevaluación Diagnóstica , Femenino , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Heterocigoto , Hipocampo/diagnóstico por imagen , Hipocampo/patología , Homocigoto , Humanos , Ventrículos Laterales/diagnóstico por imagen , Ventrículos Laterales/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Noruega , Tamaño de los Órganos , Vitamina D/sangre
16.
Front Genet ; 11: 1022, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33101365

RESUMEN

Typical cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is caused by mutations in the human NOTCH3 gene. Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy is characterized by subcortical ischemic strokes due to severe arteriopathy and fibrotic thickening of small vessels. Blood regulating vascular smooth muscle cells (VSMCs) appear as the key target in CADASIL but the pathogenic mechanisms remain unclear. With the hypothesis that brain glucose metabolism is disrupted in VSMCs in CADASIL, we investigated post-mortem tissues and VSMCs derived from CADASIL patients to explore gene expression and protein immunoreactivity of glucose transporters (GLUTs), particularly GLUT4 and GLUT2 using quantitative RT-PCR and immunohistochemical techniques. In vitro cell model analysis indicated that both GLUT4 and -2 gene expression levels were down-regulated in VSMCs derived from CADASIL patients, compared to controls. In vitro studies further indicated that the down regulation of GLUT4 coincided with impaired glucose uptake in VSMCs, which could be partially rescued by insulin treatment. Our observations on reduction in GLUTs in VSMCs are consistent with previous findings of decreased cerebral blood flow and glucose uptake in CADASIL patients. That impaired ability of glucose uptake is rescued by insulin is also consistent with previously reported lower proliferation rates of VSMCs derived from CADASIL subjects. Overall, these observations are consistent with the development of severe cerebral arteriopathy in CADASIL, in which VSMCs are replaced by widespread fibrosis.

17.
J Alzheimers Dis ; 77(2): 831-842, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32741818

RESUMEN

BACKGROUND: Aggregation of amyloid-ß (Aß) is an early pathological event in Alzheimer's disease (AD). Consequently, measures of pathogenic aggregated Aß are attractive biomarkers for AD. Here, we use a recently developed Thioflavin-T-Fluorescence Correlation Spectroscopy (ThT-FCS) assay to quantify structured ThT-responsive protein aggregates, so-called nanoplaques, in the cerebrospinal fluid (CSF). OBJECTIVE: The overall aim of this work was to assess whether ThT-FCS determined CSF nanoplaque levels could predict amyloid brain uptake as determined by 18F-Flutemetamol PET analysis. Further, we assess whether nanoplaque levels could predict clinical AD. METHODS: Nanoplaque levels in the CSF from 54 memory clinic patients were compared between sub-groups classified by 18F-Flutemetamol PET as amyloid-positive or amyloid-negative, and by clinical assessment as AD or non-AD. RESULTS: Nanoplaque levels did not differ between amyloid groups and could not predict brain amyloid uptake. However, nanoplaque levels were significantly increased in patients with clinical AD, and were significant predictors for AD when adjusting for age, sex, cognitive function, and apolipoprotein E (APOE) genotype. CONCLUSION: The concentration of nanoplaques in the CSF differentiates patients with clinical AD from non-AD patients.


Asunto(s)
Enfermedad de Alzheimer/líquido cefalorraquídeo , Amiloide/líquido cefalorraquídeo , Encéfalo/metabolismo , Nanopartículas/metabolismo , Servicio Ambulatorio en Hospital , Placa Amiloide/líquido cefalorraquídeo , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Biomarcadores/líquido cefalorraquídeo , Encéfalo/diagnóstico por imagen , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Placa Amiloide/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos
18.
Eur Geriatr Med ; 11(5): 869-878, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32588380

RESUMEN

PURPOSE: To present an insight of the situation of geriatric medicine in Balkan countries, as it was presented in the context of the 2nd pre-congress seminar of the 16th European Geriatric Medicine Society (EuGMS) Congress Athens 2021. METHODS: Representatives from 8 Balkan countries (Albania, Croatia, Greece, Republic of North Macedonia, Romania, Serbia, Slovenia, Turkey) answered 3 questions to reflect the state of geriatric medicine in their country: education on geriatrics; systems/methods for assessment of functional status and frailty; pre-operative risk assessment. An open discussion followed. RESULTS: Undergraduate education in geriatric medicine seems underestimated in medical faculties of Balkan countries, whereas a high heterogeneity is observed at a post-graduate level. Only a few Balkan countries have geriatric medicine as a recognized medical specialty or subspecialty. Functional status and frailty are only sporadically assessed, and pre-operative risk assessment is very rarely performed with a geriatric focus. Scarcity of expertise and structures relevant to geriatric medicine seems to be common. Developing a training curriculum and geriatrics-related structures are two interconnected aspects. Cooperation among physicians and multidisciplinary teams are essential for the practice of geriatric medicine. A functional geriatric network is eventually necessary and ambulatory geriatric expertise is probably a feasible and clinically relevant starting point. Providing pragmatic solutions to the pressing challenges in variable clinical settings, supplementing and working in harmony with existing components of each health system, is probably the most convincing strategy to gain political support in developing geriatric medicine. CONCLUSION: Balkan countries share common experiences and challenges in developing geriatrics. Whilst the principles of geriatric medicine are perhaps universal, proposed solutions should be adapted to each country's specific circumstances. Cooperation of the Balkan countries could promote in each the development of geriatric medicine. EuGMS is willing to foster relevant actions.


Asunto(s)
Geriatría , Anciano , Albania , Peninsula Balcánica , Croacia , Grecia , Humanos , República de Macedonia del Norte , Rumanía , Serbia , Eslovenia , Turquía
19.
Lakartidningen ; 1172020 03 09.
Artículo en Sueco | MEDLINE | ID: mdl-32154904

RESUMEN

Alzheimer's disease is the most common cause of dementia. As many as 250,000 people in Sweden will have a dementia disease in 2050. The ¼amyloid cascade hypothesis« is a common model which explains how ß-amyloid affects the function of the nerve cells. Alzheimer's disease has a long-lasting course and can present in typical and atypical forms. CSF analyses for ¼core AD CSF biomarkers« and synaptic proteins have been available for clinical diagnostics. PET scanning can detect either ß-amyloid or tau aggregates in the brain of living humans. Current Alzheimer's disease therapy is based on two classes of cognition-enhancing drugs: acetylcholinesterase inhibitor and NMDA-receptor antagonist, which delays cognitive decline in most patients. The latest clinical development of potential therapy for Alzheimer's is active or passive immunotherapy against brain ß-amyloid and tau, where several studies have shown varying but promising treatment effects. Non-pharmacological interventions in patients with AD aim to delay the loss of mental abilities, helping people to be independent in everyday life for as long as possible, and to increase their well-being and quality of life.


Asunto(s)
Enfermedad de Alzheimer , Demencia , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides , Biomarcadores , Demencia/etiología , Humanos , Calidad de Vida , Suecia , Proteínas tau
20.
Front Aging Neurosci ; 12: 608628, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33488383

RESUMEN

Accurate biomarkers of Alzheimer's disease (AD) are essential for early diagnosis and intervention. Available biomarkers are not sufficient to permit the monitoring of AD progression over time, and additional biomarkers are required. Measures of aggregated amyloid-ß (Aß) could be useful biomarkers for AD. Here, we investigate whether levels of Thioflavin-T (ThT) positive amyloid aggregates, i.e., nanoplaques, in cerebrospinal fluid (CSF) could serve as useful biomarkers for AD. One-hundred and eighteen memory clinic patients were AT(N) classified, and CSF nanoplaque concentrations were compared between patients on the "Alzheimer's continuum" (A+ patients) and patients with "Normal AD biomarkers" or "Non-AD pathologic change" (A- patients). CSF nanoplaque concentrations and sizes were quantified using the novel ThT-Fluorescence Correlation Spectroscopy (ThT-FCS) assay, and core biomarkers (Aß42, total tau and phosphorylated tau) were determined by enzyme-linked immunosorbent assays. We investigated the association between nanoplaque concentrations and core biomarkers, and the diagnostic value of nanoplaque levels. Nanoplaque levels were increased in A+ patients compared to A- patients. Nanoplaque concentrations were negatively associated with Aß42, but not related to total tau or phosphorylated tau measures. Quantification of nanoplaques did not improve the classification of patients on the Alzheimer's continuum compared to the core biomarkers alone. Dynamic changes in nanoplaques concentration and size throughout AD stages should be explored in longitudinal studies.

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