RESUMEN
Seizures are increasingly being recognized as the hallmark of Alzheimer's disease (AD). Neuronal hyperactivity can be a consequence of neuronal damage caused by abnormal amyloid ß (Aß) depositions. However, it can also be a cell-autonomous phenomenon causing AD by Aß-independent mechanisms. Various studies using animal models have shown that Ca2+ is released from the endoplasmic reticulum (ER) via type 1 inositol triphosphate receptors (InsP3R1s) and ryanodine receptors (RyRs). To investigate which is the main pathophysiological mechanism in human neurons, we measured Ca2+ signaling in neural cells derived from three early-onset AD patients harboring Presenilin-1 variants (PSEN1 p.A246E, p.L286V, and p.M146L). Of these, it has been reported that PSEN1 p.A246E and p.L286V did not produce a significant amount of abnormal Aß. We found all PSEN1-mutant neurons, but not wild-type, caused abnormal Ca2+-bursts in a manner dependent on the calcium channel, Ryanodine Receptor 2 (RyR2). Indeed, carvedilol, an RyR2 inhibitor, and VK-II-86, an analog of carvedilol without the ß-blocking effects, sufficiently eliminated the abnormal Ca2+ bursts. In contrast, Dantrolene, an inhibitor of RyR1 and RyR3, and Xestospongin c, an IP3R inhibitor, did not attenuate the Ca2+-bursts. The Western blotting showed that RyR2 expression was not affected by PSEN1 p.A246E, suggesting that the variant may activate the RyR2. The RNA-Seq data revealed that ER-stress responsive genes were increased, and mitochondrial Ca2+-transporter genes were decreased in PSEN1A246E cells compared to the WT neurons. Thus, we propose that aberrant Ca2+ signaling is a key link between human pathogenic PSEN1 variants and cell-intrinsic hyperactivity prior to deposition of abnormal Aß, offering prospects for the development of targeted prevention strategies for at-risk individuals.
Asunto(s)
Enfermedad de Alzheimer , Señalización del Calcio , Calcio , Neuronas , Presenilina-1 , Canal Liberador de Calcio Receptor de Rianodina , Humanos , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Canal Liberador de Calcio Receptor de Rianodina/genética , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Presenilina-1/genética , Presenilina-1/metabolismo , Neuronas/metabolismo , Neuronas/efectos de los fármacos , Señalización del Calcio/efectos de los fármacos , Calcio/metabolismo , Retículo Endoplásmico/metabolismo , Retículo Endoplásmico/efectos de los fármacos , Masculino , FemeninoRESUMEN
CHCHD2 and CHCHD10, linked to Parkinson's disease and amyotrophic lateral sclerosis-frontotemporal dementia (ALS), respectively, are mitochondrial intermembrane proteins that form a heterodimer. This study aimed to investigate the impact of the CHCHD2 P14L variant, implicated in ALS, on mitochondrial function and its subsequent effects on cellular homeostasis. The missense variant of CHCHD2, P14L, found in a cohort of patients with ALS, mislocalized CHCHD2 to the cytoplasm, leaving CHCHD10 in the mitochondria. Drosophila lacking the CHCHD2 ortholog exhibited mitochondrial degeneration. In contrast, human CHCHD2 P14L, but not wild-type human CHCHD2, failed to suppress this degeneration, suggesting that P14L is a pathogenic variant. The mitochondrial Ca2+ buffering capacity was reduced in Drosophila neurons expressing human CHCHD2 P14L. The altered Ca2+-buffering phenotype was also observed in cultured human neuroblastoma SH-SY5Y cells expressing CHCHD2 P14L. In these cells, transient elevation of cytoplasmic Ca2+ facilitated the activation of calpain and caspase-3, accompanied by the processing and insolubilization of TDP-43. These observations suggest that CHCHD2 P14L causes abnormal Ca2+ dynamics and TDP-43 aggregation, reflecting the pathophysiology of ALS.
RESUMEN
PURPOSE: To examine the extent to which patients with amnestic mild cognitive impairment (aMCI) or Alzheimer's disease (AD) perceive their own physical decline. METHODS: This study included 4450 outpatients (1008 normal cognition [NC], 1605 aMCI, and 1837 mild AD) who attended an initial visit to a memory clinic between July 2010 and June 2021. Their physical function was assessed by the Timed Up and Go test, one-leg standing test, and grip strength. For physical complaints, data were obtained on reports of fear of falling and dizziness or staggering. Logistic regression analysis was performed to compare the patients' physical function and complaints for each stage of NC, aMCI, and mild AD. RESULTS: Objective physical function declined from aMCI and the mild AD stage, but subjective physical complaints decreased by 20-50% in aMCI and 40-60% in mild AD compared with the NC group. CONCLUSION: As objective physical functional declined from the aMCI stage onward, subjective physical complaints decreased. This suggests a need for objective assessment of physical function in aMCI and mild AD patients even when they have no physical complaints in the clinical setting.
RESUMEN
Previous studies have demonstrated associations between enlarged perivascular spaces (EPVS) and dementias such as Alzheimer's disease. However, an association between EPVS and dementia with Lewy bodies (DLB) has not yet been clarified. We performed a cross-sectional analysis of our prospective study cohort of 109 participants (16 with DLB). We assessed cognitive function, pulse wave velocity (PWV), and brain magnetic resonance imaging features. The relationships between EPVS and DLB were evaluated using multivariable logistic regression analyses. Compared with the non-dementia group, the DLB group was more likely to have EPVS in the basal ganglia. Compared with participants without EPVS, those with EPVS were older and had cognitive impairment and high PWV. In multivariable analyses, EPVS in the basal ganglia was independently associated with DLB. High PWV was also independently associated with EPVS in both the basal ganglia and centrum semiovale. High PWV may cause cerebrovascular pulsatility, leading to accelerated EPVS in DLB participants.
Asunto(s)
Sistema Glinfático , Enfermedad por Cuerpos de Lewy , Análisis de la Onda del Pulso , Humanos , Enfermedad por Cuerpos de Lewy/fisiopatología , Enfermedad por Cuerpos de Lewy/diagnóstico por imagen , Enfermedad por Cuerpos de Lewy/patología , Femenino , Masculino , Anciano , Sistema Glinfático/diagnóstico por imagen , Sistema Glinfático/fisiopatología , Sistema Glinfático/patología , Estudios Transversales , Imagen por Resonancia Magnética , Estudios Prospectivos , Anciano de 80 o más Años , Ganglios Basales/diagnóstico por imagen , Ganglios Basales/fisiopatología , Ganglios Basales/patologíaRESUMEN
Objective: To develop a combined index using cognitive function and instrumental activities of daily living (IADL) to discriminate between Clinical Dementia Rating (CDR) scores of 0.5 and 1 in the clinical setting, and to investigate its optimal cutoff values and internal and external validities.Methods: We included outpatients aged 65-89 years with CDR scores of 0.5 or 1. The optimal cutoff values and internal validity were verified using Japanese memory clinic-based datasets between September 2010 and October 2021 [National Center for Geriatrics and Gerontology (NCGG) datasets]. Cognitive function and IADL were assessed using the Mini-Mental State Examination (MMSE) and Lawton Index (LI), respectively. The optimal cutoff values were defined using the Youden Index. To verify internal validity, sensitivity and specificity were calculated using stratified 5-fold cross-validation. To verify external validity, sensitivity and specificity of the optimal cutoff values were assessed in the Organized Registration for the Assessment of dementia on Nationwide General consortium toward Effective treatment (ORANGE) Registry dataset between July 2015 and March 2022, which has multicenter clinical data.Results: A total of 800 (mean age, 77.53 years; men, 50.1%) and 1494 (mean age, 77.97 years; men, 43.3%) participants comprised the NCGG and ORANGE Registry datasets, respectively. The optimum cutoff values for men and women were determined as MMSE < 25 and LI < 5 and MMSE < 25 and LI < 8, respectively; such a combined index showed good discriminative performance in internal (sensitivity/specificity: men, 92.50/73.52; women, 88.57/65.65) and external validities (men, 81.43/77.62; women, 77.64/74.67).Conclusion: The index developed is useful in discriminating between CDR scores of 0.5 and 1 and should be applicable to various settings, such as memory clinics and clinical research.
Asunto(s)
Actividades Cotidianas , Demencia , Pruebas de Estado Mental y Demencia , Humanos , Anciano , Femenino , Masculino , Anciano de 80 o más Años , Demencia/diagnóstico , Pruebas de Estado Mental y Demencia/normas , Pruebas de Estado Mental y Demencia/estadística & datos numéricos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Disfunción Cognitiva/diagnóstico , JapónRESUMEN
AIM: To examine cross-sectional associations between continuous glucose monitoring (CGM)-derived metrics and cerebral small vessel disease (SVD) in older adults with type 2 diabetes. MATERIALS AND METHODS: In total, 80 patients with type 2 diabetes aged ≥70 years were analysed. Participants underwent CGM for 14 days. From the CGM data, we derived mean sensor glucose, percentage glucose coefficient of variation, mean amplitude of glucose excursion, time in range (TIR, 70-180 mg/dl), time above range (TAR) and time below range metrics, glycaemia risk index and high/low blood glucose index. The presence of cerebral SVD, including lacunes, microbleeds, enlarged perivascular spaces and white matter hyperintensities, was assessed, and the total number of these findings comprised the total cerebral SVD score (0-4). Ordinal logistic regression analyses were performed to examine the association of CGM-derived metrics with the total SVD score. RESULTS: The median SVD score was 1 (interquartile range 0-2). Higher hyperglycaemic metrics, including mean sensor glucose, TAR >180 mg/dl, TAR >250 mg/dl, and high blood glucose index and glycaemia risk index, were associated with a higher total SVD score. In contrast, a higher TIR (per 10% increase) was associated with a lower total SVD score (odds ratio 0.73, 95% confidence interval 0.56-0.95). Glycated haemoglobin, percentage glucose coefficient of variation, mean amplitude of glucose excursions, time below range and low blood glucose index were not associated with total cerebral SVD scores. CONCLUSIONS: The hyperglycaemia metrics and TIR, derived from CGM, were associated with cerebral SVD in older adults with type 2 diabetes.
Asunto(s)
Automonitorización de la Glucosa Sanguínea , Glucemia , Enfermedades de los Pequeños Vasos Cerebrales , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/complicaciones , Masculino , Femenino , Anciano , Estudios Transversales , Enfermedades de los Pequeños Vasos Cerebrales/sangre , Glucemia/análisis , Glucemia/metabolismo , Anciano de 80 o más Años , Angiopatías Diabéticas/sangre , Angiopatías Diabéticas/epidemiología , Angiopatías Diabéticas/diagnóstico , Angiopatías Diabéticas/etiología , Hiperglucemia/sangre , Monitoreo Continuo de GlucosaRESUMEN
Background: Positron emission tomography, which assesses the binding of translocator protein radiotracers, 11C-DPA-713, may be a sensitive method for determining glial-mediated neuroinflammation levels. This study investigated the relationship between regional 11C-DPA713 binding potential (BPND) and anxiety in patients with Alzheimer's disease (AD) continuum. Methods: Nineteen patients with AD continuum determined to be amyloid-/p-tau 181-positive via cerebrospinal fluid analysis were included in this cross-sectional study (mild cognitive impairment [MCI, n = 5] and AD [n = 14]). Anxiety was evaluated using the State-Trait Anxiety Inventory (STAI). A whole-brain voxel-based analysis was performed to examine the relationship between 11C-DPA-713-BPND values at each voxel and the STAI score. Stepwise multiple regression analysis was performed to determine the predictors of STAI scores using independent variables, including 11C-DPA-713-BPND values within significant clusters. 11C-DPA-713-BPND values were compared between patients with AD continuum with low-to-moderate and high STAI scores. Results: Voxel-based analysis revealed a positive correlation between trait anxiety severity and 11C-DPA713-BPND values in the centromedial amygdala and the left inferior occipital area [P < 0.001 (uncorrected) at the voxel-level]. 11C-DPA713-BPND values in these regions were a strong predictor of the STAI trait anxiety score. Specifically, patients with AD continuum and high trait anxiety had increased 11C-DPA713-BPND values in these regions. Conclusions: The amygdala-occipital lobe circuit influences the control of emotional generation, and disruption of this network by AD pathology-induced inflammation may contribute to the expression of anxiety. Our findings suggest that suppression of inflammation can help effectively treat anxiety by attenuating damage to the amygdala and its associated areas.
RESUMEN
Inherited arrhythmia syndromes (IASs) can cause life-threatening arrhythmias and are responsible for a significant proportion of sudden cardiac deaths (SCDs). Despite progress in the development of devices to prevent SCDs, the precise molecular mechanisms that induce detrimental arrhythmias remain to be fully investigated, and more effective therapies are desirable. In the present study, we screened a large-scale randomly mutagenized mouse library by electrocardiography to establish a disease model of IASs and consequently found one pedigree that exhibited spontaneous ventricular arrhythmias (VAs) followed by SCD within 1 y after birth. Genetic analysis successfully revealed a missense mutation (p.I4093V) of the ryanodine receptor 2 gene to be a cause of the arrhythmia. We found an age-related increase in arrhythmia frequency accompanied by cardiomegaly and decreased ventricular contractility in the Ryr2I4093V/+ mice. Ca2+ signaling analysis and a ryanodine binding assay indicated that the mutant ryanodine receptor 2 had a gain-of-function phenotype and enhanced Ca2+ sensitivity. Using this model, we detected the significant suppression of VA following flecainide or dantrolene treatment. Collectively, we established an inherited life-threatening arrhythmia mouse model from an electrocardiogram-based screen of randomly mutagenized mice. The present IAS model may prove feasible for use in investigating the mechanisms of SCD and assessing therapies.
Asunto(s)
Taquicardia Ventricular , Ratones , Animales , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Arritmias Cardíacas/genética , Flecainida , Mutación Missense , Muerte Súbita Cardíaca , MutaciónRESUMEN
INTRODUCTION: We examined the efficacy of a multidomain intervention in preventing cognitive decline among Japanese older adults with mild cognitive impairment (MCI). METHODS: Participants aged 65-85 years with MCI were randomized into intervention (management of vascular risk factors, exercise, nutritional counseling, and cognitive training) and control groups. The primary outcome was changes in the cognitive composite score over a period of 18 months. RESULTS: Of 531 participants, 406 completed the trial. The between-group difference in composite score changes was 0.047 (95% CI: -0.029 to 0.124). Secondary analyses indicated positive impacts of interventions on several secondary health outcomes. The interventions appeared to be particularly effective for individuals with high attendance during exercise sessions and those with the apolipoprotein E ε4 allele and elevated plasma glial fibrillary acidic protein levels. DISCUSSION: The multidomain intervention showed no efficacy in preventing cognitive decline. Further research on more efficient strategies and suitable target populations is required. HIGHLIGHTS: This trial evaluated the efficacy of multidomain intervention in individuals with MCI. The trial did not show a significant difference in preplanned cognitive outcomes. Interventions had positive effects on a wide range of secondary health outcomes. Those with adequate adherence or high risk of dementia benefited from interventions.
Asunto(s)
Disfunción Cognitiva , Demencia , Humanos , Masculino , Femenino , Anciano , Japón , Anciano de 80 o más Años , Disfunción Cognitiva/prevención & control , Demencia/prevención & control , Resultado del Tratamiento , Terapia Cognitivo-Conductual/métodos , Factores de Riesgo , Apolipoproteína E4/genética , Terapia por Ejercicio/métodosRESUMEN
This observational pilot study aimed to investigate continuous glucose monitoring (CGM) metrics in older Japanese patients with type 2 diabetes mellitus (T2DM) using a CGM system (FreeStyle Libre Pro) during the first tirzepatide administration and compare the glycemic control measures before and after the initial injection. The four patients had a mean age of 79.5 years (standard deviation [SD]: 5.8), a mean body mass index of 24.6 kg/m2 (SD: 4.7), a mean glycated hemoglobin level of 9.1% (SD: 2.1), and a mean measurement period of 10.5 days (SD: 3.5). After the inclusion of tirzepatide treatment, the mean of time in range, time above range, and time below range changed from 53.2% to 78.9% (p = 0.041), 45.8% to 19.7% (p = 0.038), and 1.0% to 1.5% (p = 0.206), respectively. Improved hyperglycemia reduced the oral hypoglycemic medication in two cases and decreased the frequency of insulin injections in two cases. To elucidate the potential benefits of tirzepatide, future studies should investigate the long-term impact on functional prognosis, safety, and tolerability and distinguish between the use of other weekly agonists, especially in nonobese older Asian patients. However, tirzepatide-associated robust glycemic improvement may simplify diabetes treatment regimens in older patients with T2DM.
RESUMEN
BACKGROUND: Behavioral and psychological symptoms of dementia (BPSD) are common among people with dementia from the early stages and can appear even in mild cognitive impairment (MCI). However, the prognostic impact of BPSD is unclear. This study examined the association between BPSD and mortality among people with cognitive impairment. METHODS: This longitudinal study involved 1,065 males and 1,681 females (mean age: males = 77.1 years; females = 78.6 years) with MCI or dementia diagnosis, from the National Center for Geriatrics and Gerontology-Life Stories of People with Dementia (NCGG-STORIES), a single-center memory clinic-based cohort study in Japan that registered first-time outpatients from 2010-2018. Information about death was collected through a mail survey returned by participants or their close relatives, with an up to 8-year follow-up. BPSD was assessed using the Dementia Behavior Disturbance Scale (DBD) at baseline. RESULTS: During the follow-up period, 229 (28.1%) male and 254 (15.1%) female deaths occurred. Cox proportional hazards regression analysis showed that higher DBD scores were significantly associated with increased mortality risk among males, but not females (compared with the lowest quartile score group, hazard ratios [95% confidence intervals] for the highest quartile score group = 1.59 [1.11-2.29] for males and 1.06 [0.66-1.70] for females). Among the DBD items, lack of interest in daily living, excessive daytime sleep, and refusal to receive care had a higher mortality risk. CONCLUSIONS: The findings suggest a potential association between BPSD and poor prognosis among males with cognitive impairment.
RESUMEN
AIMS/INTRODUCTION: This study aimed to characterize the global cognition and executive functions of older adults with type 1 diabetes mellitus in comparison with type 2 diabetes mellitus. MATERIALS AND METHODS: This study included 37 patients with type 1 diabetes mellitus aged ≥65 years and 37 age- and sex-matched patients with type 2 diabetes mellitus. Patients with dementia scoring <24 on the Mini-Mental State Examination were excluded. General cognition, memory, classic, and practical executive function were investigated. RESULTS: Patients with type 1 diabetes mellitus demonstrated lower psychomotor speed scores on Trail Making Tests A and B (P < 0.001, P < 0.013) than those with type 2 diabetes mellitus. The dysexecutive syndrome behavioral assessment revealed similar results in patients with types 1 and 2 diabetes mellitus. The Wechsler Memory Scale-Revised verbal episodic memory and Montreal Cognitive Assessment Japanese version were similar in terms of general cognition, but worse delayed recall subset on the latter was associated with type 2 diabetes mellitus (P = 0.038). A worse Trail Making Test-A performance was associated with type 1 diabetes mellitus and age (P < 0.004, P < 0.029). CONCLUSIONS: Executive function of psychomotor speed was worse in older outpatient adults without dementia with type 1 diabetes mellitus than in those with type 2 diabetes mellitus but with no significant differences in the comprehensive and practical behavioral assessment of dysexecutive syndrome. Patients with type 1 diabetes had more severely impaired executive function, whereas those with type 2 had greater impaired memory than executive function.
Asunto(s)
Cognición , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Función Ejecutiva , Humanos , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/psicología , Masculino , Femenino , Anciano , Diabetes Mellitus Tipo 2/psicología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/fisiopatología , Demencia/etiología , Demencia/psicología , Pruebas Neuropsicológicas , Anciano de 80 o más AñosRESUMEN
OBJECTIVE: To determine the impact of type 2 diabetes and glycated hemoglobin (HbA1c) levels within the recommended target range according to the Japan Diabetes Society/Japan Geriatrics Society Joint Committee on mortality in older adults with cognitive impairment. RESEARCH DESIGN AND METHODS: This retrospective cohort study included 1,528 and 468 patients aged ≥65 years without and with type 2 diabetes, respectively, who were visiting a memory clinic. The 468 patients with type 2 diabetes were divided into three groups (within, above, and below the target range) based on their HbA1c levels, cognitive function, ability to perform activities of daily living, and medications associated with a high risk of hypoglycemia. The impact of diabetes and HbA1c levels on mortality was evaluated using Cox proportional hazards models. RESULTS: Over a median follow-up period of 3.8 years, 353 patients (17.7%) died. Compared with individuals without type 2 diabetes, HbA1c levels above (hazard ratio [HR] 1.70, 95% CI 1.08-2.69) and below (HR 2.15, 95% CI 1.33-3.48) the target range were associated with a higher risk of death; however, HbA1c levels within the target range were not (HR 1.02, 95% CI 0.77-1.36). CONCLUSIONS: HbA1c levels above and below the target range were associated with a higher risk of mortality, whereas patients with HbA1c levels within the target range did not exhibit a higher risk of mortality than individuals without type 2 diabetes. These results provide empirical support for the current target ranges among older adults with cognitive impairment.
Asunto(s)
Disfunción Cognitiva , Diabetes Mellitus Tipo 2 , Humanos , Anciano , Diabetes Mellitus Tipo 2/complicaciones , Hemoglobina Glucada , Estudios Retrospectivos , Actividades Cotidianas , Factores de Riesgo , Disfunción Cognitiva/complicacionesRESUMEN
BACKGROUND: Dementia often results in postural control impairment, which could signify central nervous system dysfunction. However, no studies have compared postural control characteristics among various types of dementia. This study aimed to compare static postural control in patients with Alzheimer's disease (AD), dementia with Lewy bodies (DLB), and vascular dementia (VaD). METHODS: Cross-sectional relationship between the clinical diagnoses (AD, DLB, VaD, or normal cognition [NC]) of outpatients at a memory clinic and their upright postural control characteristics were examined. In the postural control test, participants were instructed to maintain a static upright standing on a stabilometer for 60 seconds under the eyes-open and eyes-closed conditions. Forty postural control parameters, including distance, position, and velocity in the anterior-posterior and medio-lateral directions, derived from the trajectory of the center of mass sway, were calculated. The characteristics of each type of dementia were compared to those of NC, and the differences among the 3 types of dementia were evaluated using linear regression models. RESULTS: The study included 1 789 participants (1 206 with AD, 111 with DLB, 49 with VaD, and 423 with NC). Patients with AD exhibited distinct postural control characteristics, particularly in some distance and velocity parameters, only in the eyes-closed condition. Those with DLB exhibited features in the mean position in the anterior-posterior direction. In patients with VaD, significant differences were observed in most parameters, except the power spectrum. CONCLUSIONS: Patients with AD, DLB, and VaD display disease-specific postural control characteristics when compared to cognitively normal individuals.
Asunto(s)
Enfermedad de Alzheimer , Demencia Vascular , Enfermedad por Cuerpos de Lewy , Humanos , Enfermedad de Alzheimer/diagnóstico , Enfermedad por Cuerpos de Lewy/diagnóstico , Equilibrio PosturalRESUMEN
OBJECTIVES: This study aimed to investigate the association between abdominal adiposity and change in cognitive function in community-dwelling older adults. DESIGN, SETTING, AND PARTICIPANTS: This longitudinal study included older adults aged ≥60 years without cognitive impairment who participated in the National Institute for Longevity Sciences - Longitudinal Study of Aging. MEASUREMENTS: Cognitive function was evaluated biennially using the Mini-Mental State Examination (MMSE) over 10 years. Waist circumference (WC) was measured at the naval level, and subcutaneous fat area (SFA) and visceral fat area (VFA) were assessed using baseline computed tomography scans. WC, SFA, and VFA areas were stratified into sex-adjusted tertiles. A linear mixed model was applied separately for men and women. RESULTS: This study included 873 older adults. In men, the groups with the highest levels of WC, SFA, and VFA exhibited a greater decline in MMSE score than the groups with the lowest levels (ß [95% confidence interval]: WC, -0.12 [-0.23 to -0.01]; SFA, -0.13 [-0.24 to -0.02]; VFA, -0.11 [-0.22 to -0.01]). In women, the group with the highest level of WC and SFA showed a greater decline in MMSE score than the group with the lowest level (WC, -0.12 [-0.25 to -0.01]; SFA, -0.18 [-0.30 to -0.06]), but VFA was not associated with cognitive decline. CONCLUSION: Higher WC, SFA, and VFA in men and higher WC and SFA in women were identified as risk factors for cognitive decline in later life, suggesting that abdominal adiposity involved in cognitive decline may differ according to sex.
Asunto(s)
Adiposidad , Disfunción Cognitiva , Masculino , Humanos , Femenino , Anciano , Estudios Longitudinales , Obesidad Abdominal/complicaciones , Factores de Riesgo , Grasa Intraabdominal/diagnóstico por imagen , Disfunción Cognitiva/epidemiología , Disfunción Cognitiva/etiología , Índice de Masa CorporalRESUMEN
BACKGROUND: Akt plays diverse roles in humans. It is involved in the pathogenesis of type 2 diabetes mellitus (T2DM), which is caused by insulin resistance. Akt also plays a vital role in human platelet activation. Furthermore, the hippocampus is closely associated with memory and learning, and a decrease in hippocampal volume is reportedly associated with an insulin-resistant phenotype in T2DM patients without dementia. AIM: To investigate the relationship between Akt phosphorylation in unstimulated platelets and the hippocampal volume in T2DM patients. METHODS: Platelet-rich plasma (PRP) was prepared from the venous blood of patients with T2DM or age-matched controls. The pellet lysate of the centrifuged PRP was subjected to western blotting to analyse the phosphorylation of Akt, p38 mitogen-activated protein (MAP) kinase and glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Phosphorylation levels were quantified by densitometric analysis. Hippocampal volume was analysed using a voxel-based specific regional analysis system for Alzheimer's disease on magnetic resonance imaging, which proposes the Z-score as a parameter that reflects hippocampal volume. RESULTS: The levels of phosphorylated Akt corrected with phosphorylated p38 MAP kinase were inversely correlated with the Z-scores in the T2DM subjects, whereas the levels of phosphorylated Akt corrected with GAPDH were not. However, this relationship was not observed in the control patients. CONCLUSION: These results suggest that an inverse relationship may exist between platelet Akt activation and hippocampal atrophy in T2DM patients. Our findings provide insight into the molecular mechanisms underlying T2DM hippocampal atrophy.
RESUMEN
AIM: The study aimed to investigate the association of vitality, as measured using the vitality index (Vix), with the survival outcomes of older adults with mild cognitive impairment (MCI) or dementia. METHODS: We analyzed data from 3731 patients in the National Center for Geriatrics and Gerontology - Life Stories of Individuals with Dementia cohort from July 2010 to September 2018. The main focus was to correlate Vix scores with the time from the initial visit to death. Vix was categorized into "moderately to severely impaired" (0-7 points), "mildly impaired" (8-9 points), and "normal" (10 points) groups. Survival outcomes were assessed using a Cox proportional hazards model, adjusted for various factors. We conducted a mediation analysis to evaluate the effect of body mass index (BMI), instrumental activities of daily living (IADL), and basic activities of daily living (BADL) on the association between vitality and mortality. Stratified analysis was also conducted for the Mini-Mental State Examination groups. RESULTS: We included 2740 patients with an average follow-up of 1315 days. The mortality rate was 15.7%. The Vix distribution was 16% at 0-7 points; 40%, 8-9 points; and 44%, 10 points. Patients in the "moderately to severely impaired" category, characterized by lower Vix scores, exhibited notably higher mortality rates. Mediation effects emphasized the significant roles of BMI, IADL, and BADL in influencing survival outcomes. CONCLUSIONS: Vitality significantly influences patient survival rates. The association between vitality and mortality seems to be mediated by IADL and BADL, which has significant clinical implications. Geriatr Gerontol Int 2024; 24: 221-228.
Asunto(s)
Disfunción Cognitiva , Demencia , Humanos , Anciano , Estudios Retrospectivos , Actividades Cotidianas/psicología , Disfunción Cognitiva/diagnóstico , Pruebas de Estado Mental y Demencia , Demencia/diagnósticoRESUMEN
The link between changes in astrocyte function and the pathological progression of Alzheimer's disease (AD) has attracted considerable attention. Interestingly, activated astrocytes in AD show abnormalities in their lipid content and metabolism. In particular, the expression of apolipoprotein E (ApoE), a lipid transporter, is decreased. Because ApoE has anti-inflammatory and amyloid ß (Aß)-metabolizing effects, the nuclear receptors, retinoid X receptor (RXR) and LXR, which are involved in ApoE expression, are considered promising therapeutic targets for AD. However, the therapeutic effects of agents targeting these receptors are limited or vary considerably among groups, indicating the involvement of an unknown pathological factor that modifies astrocyte and ApoE function. Here, we focused on the signaling lipid, sphingosine-1-phosphate (S1P), which is mainly produced by sphingosine kinase 2 (SphK2) in the brain. Using astrocyte models, we found that upregulation of SphK2/S1P signaling suppressed ApoE induction by both RXR and LXR agonists. We also found that SphK2 activation reduced RXR binding to the APOE promoter region in the nucleus, suggesting the nuclear function of SphK2/S1P. Intriguingly, suppression of SphK2 activity by RNA knockdown or specific inhibitors upregulated lipidated ApoE induction. Furthermore, the induced ApoE facilitates Aß uptake in astrocytes. Together with our previous findings that SphK2 activity is upregulated in AD brain and promotes Aß production in neurons, these results indicate that SphK2/S1P signaling is a promising multifunctional therapeutic target for AD that can modulate astrocyte function by stabilizing the effects of RXR and LXR agonists, and simultaneously regulate neuronal pathogenesis.
Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Humanos , Péptidos beta-Amiloides/metabolismo , Astrocitos/metabolismo , Enfermedad de Alzheimer/metabolismo , Encéfalo/metabolismo , Apolipoproteínas E/metabolismoRESUMEN
Late-onset Alzheimer's disease (LOAD) is the most common cause of dementia among those older than 65 years. The onset of LOAD is influenced by neuroinflammation. The human leukocyte antigen (HLA) system is involved in regulating inflammatory responses. Numerous HLA alleles and their haplotypes have shown varying associations with LOAD in diverse populations, yet their impact on the Japanese population remains to be elucidated. Here, we conducted a comprehensive investigation into the associations between LOAD and HLA alleles within the Japanese population. Using whole-genome sequencing (WGS) data from 303 LOAD patients and 1717 cognitively normal (CN) controls, we identified four-digit HLA class I alleles (A, B, and C) and class II alleles (DRB1, DQB1, and DPB1). We found a significant association between the HLA-DRB1*09:01-DQB1*03:03 haplotype and LOAD risk in APOE [Formula: see text]4-negative samples (odds ratio = 1.81, 95% confidence interval = 1.38-2.38, P = 2.03[Formula: see text]). These alleles not only showed distinctive frequencies specific to East Asians but demonstrated a high degree of linkage disequilibrium in APOE [Formula: see text]4-negative samples (r2 = 0.88). Because HLA class II molecules interact with T-cell receptors (TCRs), we explored potential disparities in the diversities of TCR α chain (TRA) and ß chain (TRB) repertoires between APOE [Formula: see text]4-negative LOAD and CN samples. Lower diversity of TRA repertoires was associated with LOAD in APOE [Formula: see text]4-negative samples, irrespective of the HLA DRB1*09:01-DQB1*03:03 haplotype. Our study enhances the understanding of the etiology of LOAD in the Japanese population and provides new insights into the underlying mechanisms of its pathogenesis.
RESUMEN
BACKGROUND: Non-pharmacological interventions effective for depressive mood and bilateral relationships among persons with cognitive impairment (PwCI) and their family caregivers (FCGs) have not been established. OBJECTIVE: To examine the feasibility of a newly developed group-based art appreciation and self-expression program (NCGG-ART) for dyads of PwCI and their FCGs. METHODS: This pilot randomized control trial included 34 dyads of PwCI diagnosed with mild to moderate Alzheimer's disease or mild cognitive impairment, and their FCGs, from an outpatient rehabilitation service (Holistic Physio-Cognitive Rehabilitation [HPCR]). Participants were randomly divided equally into the HPCR (control group) or NCGG-ART and HPCR (intervention group) groups. Both included 1-hour weekly, 6-week programs. The primary outcome was depressive symptoms among FCGs assessed using the Patient Health Questionnaire-9 (PHQ-9). Feasibility outcomes included participant satisfaction and motivation. FCGs were interviewed about their experiences and feelings regarding the program, which were analyzed using content analysis. RESULTS: Thirty-two dyads (intervention group:16; control group:16) completed the study period. High participation rates, satisfaction, and motivation were demonstrated throughout the intervention. Scores in the PHQ-9 among FCGs did not show positive effects: mean changes in the score were 1.3 for the intervention group and -0.8 for the control group (Cohen d:0.56). However, the qualitative analysis revealed favorable experiences and feelings of the FCGs, such as positive emotions, social interactions, and person-centered attitudes to and positive relationships with PwCI. CONCLUSIONS: This program demonstrated high feasibility with FCGs' favorable responses to emotions and relationships with PwCI, ensuring future investigations with a confirmatory study design.