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The secreted peptide adropin is highly expressed in human brain tissues and correlates with RNA and proteomic risk indicators for dementia. Here we report that plasma adropin concentrations predict risk for cognitive decline in the Multidomain Alzheimer Preventive Trial (ClinicalTrials.gov Identifier, NCT00672685; mean age 75.8y, SD = 4.5 years, 60.2% female, n = 452). Cognitive ability was evaluated using a composite cognitive score (CCS) that assessed four domains: memory, language, executive function, and orientation. Relationships between plasma adropin concentrations and changes in CCS (∆CCS) were examined using Cox Proportional Hazards Regression, or by grouping into tertiles ranked low to high by adropin values and controlling for age, time between baseline and final visits, baseline CCS, and other risk factors (e.g., education, medication, APOE4 status). Risk of cognitive decline (defined as a ∆CCS of − 0.3 or more) decreased with increasing plasma adropin concentrations (hazard ratio = 0.873, 95% CI 0.780–0.977, P = 0.018). Between adropin tertiles, ∆CCS was significantly different (P = 0.01; estimated marginal mean ± SE for the 1st to 3rd tertile, − 0.317 ± 0.064; − 0.275 ± 0.063; − 0.042 ± 0.071; n = 133,146, and 130, respectively; P < 0.05 for 1st vs. 2nd and 3rd adropin tertiles). Normalized plasma Aß42/40 ratio and plasma neurofilament light chain, indicators of neurodegeneration, were significantly different between adropin tertile. These differences were consistent with reduced risk of cognitive decline with higher plasma adropin levels. Overall, these results suggest cognitive decline is reduced in community-dwelling older adults with higher circulating adropin levels. Further studies are needed to determine the underlying causes of the relationship and whether increasing adropin levels can delay cognitive decline. [ABSTRACT FROM AUTHOR]

Background: In MAPT (Multidomain Alzheimer Preventive Trial), a cognitive effect of multidomain intervention (MI) was showed in non-demented subjects with positive amyloid PET. However, screening eligible patients for multidomain intervention by PET is difficult to generalize in real-world settings. Methods: MAPT study was a 3-year, randomized, placebo-controlled trial followed by a 2-year observational and optional extension. All participants were non-demented and randomly assigned (1:1:1:1) to the MI plus omega 3, MI plus placebo, omega 3 alone, or placebo alone group. The objectives were to assess the cognitive effect of MAPT interventions (omega 3 supplementation, MI, combined intervention) in non-demented subjects according to amyloid blood status at 12, 36, and 60 months. In this subgroup analysis (n = 483), amyloid status was defined by plasma Aβ42/40 ratio (cutoff ≤ 0.0107). The primary outcome measure was the change in cognitive composite score after a 1, 3, and 5-year clinical follow-up. Results: The intention-to-treat (ITT) population included 483 subjects (161 positive and 322 negative amyloid participants based on plasma Aβ42/40 ratio). In the positive amyloid ITT population, we showed a positive effect of MI plus omega 3 on the change in composite cognitive score in 12 (raw p =.0350, 0.01917, 95% CI = [0.0136 to 0.3699]) and 36 months (raw p =.0357, 0.2818, 95% CI = [0.0190 to 0.5446]). After correction of multiple comparisons and adjustments, these differences were not significant (adjusted p =.1144 and.0690). In the per-protocol positive amyloid group (n = 154), we observed a significant difference between the combined intervention and placebo groups at 12 (p =.0313, 0.2424, 0.0571 to 0.4276) and 36 months (p =.0195, 0.3747, 0.1055 to 0.6439) persisting after adjustment. In the ITT and per-protocol analyses, no cognitive effect was observed in the positive and negative amyloid group at 60-month visit. Conclusions: These findings suggest a benefit of MI plus omega 3 in positive blood amyloid subjects. This promising trend needs to be confirmed before using blood biomarkers for screening in preventive trials. Trial registration: ClinicalTrials.gov Identifier: NCT01513252. [ABSTRACT FROM AUTHOR]

Most physiopathological mechanisms underlying blood pressure variability (BPV) are implicated in aging. Vascular aging is associated with chronic low-grade inflammation occurring in late life, known as "inflammaging" and the hallmark "mitochondrial dysfunction" due to age-related stress. We aimed to determine whether plasma levels of the pleiotropic stress-related mitokine growth/differentiation factor 15 (GDF-15) and two inflammatory biomarkers, interleukin 6 (IL-6) and tumor necrosis factor receptor 1 (TNFR-1), are associated with visit-to-visit BPV in a population of community-dwelling older adults. The study population consisted of 1096 community-dwelling participants [median age 75 (72–78) years; 699 females, 63.7%] aged ≥ 70 years from the MAPT study. Plasma blood sample was collected 12 months after enrolment and BP was assessed up to seven times over a 4-year period. Systolic (SBPV) and diastolic BPV (DBPV) were determined through several indicators taking into account BP change over time, the order of measurements and formulas independent of mean BP levels. Higher values of GDF-15 were significantly associated with increased SBPV (all indicators) after adjustment for relevant covariates [adjusted 1-SD increase in GDF-15: β (SE) = 0.07 (0.04), p < 0.044, for coefficient of variation%]. GDF-15 levels were not associated with DBPV. No significant associations were found between IL-6 and BPV, whereas TNFR1 was only partially related to DBPV. Unlike inflammation biomarkers, higher GDF-15 levels were associated with greater SBPV. Our findings support the age-related process of mitochondrial dysfunction underlying BP instability, suggesting that BPV might be a potential marker of aging. [ABSTRACT FROM AUTHOR]

Long-term use of urate-lowering therapies (ULT) may reduce inflammaging and thus prevent cognitive decline during aging. This article examined the association between long-term use of ULT and cognitive decline among community-dwelling older adults with spontaneous memory complaints. We performed a secondary observational analysis using data of 1673 participants ≥ 70 years old from the Multidomain Alzheimer Preventive Trial (MAPT Study), a randomized controlled trial assessing the effect of a multidomain intervention, the administration of polyunsaturated fatty acids (PUFA), both, or placebo on cognitive decline. We compared cognitive decline during the 5-year follow-up between three groups according to ULT (i.e. allopurinol and febuxostat) use: participants treated with ULT during at least 75% of the study period (PT ≥ 75; n = 51), less than 75% (PT < 75; n = 31), and non-treated participants (PNT; n = 1591). Cognitive function (measured by a composite score) was assessed at baseline, 6 months and every year for 5 years. Linear mixed models were performed and results were adjusted for age, sex, body mass index (BMI), diagnosis of arterial hypertension or diabetes, baseline composite cognitive score, and MAPT intervention groups. After the 5-year follow-up, only non-treated participants presented a significant decline in the cognitive composite score (mean change − 0.173, 95%CI − 0.212 to − 0.135; p < 0.0001). However, there were no differences in change of the composite cognitive score between groups (adjusted between-group difference for PT ≥ 75 vs. PNT: 0.144, 95%CI − 0.075 to 0.363, p = 0.196; PT < 75 vs. PNT: 0.103, 95%CI − 0.148 to 0.353, p = 0.421). Use of ULT was not associated with reduced cognitive decline over a 5-year follow-up among community-dwelling older adults at risk of dementia. [ABSTRACT FROM AUTHOR]

We investigated combining a core AD neuropathology measure (plasma amyloid-beta [Aβ] 42/40) with five plasma markers of inflammation, cellular stress, and neurodegeneration to predict cognitive decline. Among 401 participants free of dementia (median [IQR] age, 76 [73–80] years) from the Multidomain Alzheimer Preventive Trial (MAPT), 28 (7.0%) participants developed dementia, and 137 (34.2%) had worsening of clinical dementia rating (CDR) scale over 4 years. In the models utilizing plasma Aβ alone, a tenfold increased risk of incident dementia (nonsignificant) and a fivefold increased risk of worsening CDR were observed as each nature log unit increased in plasma Aβ levels. Models incorporating Aβ plus multiple plasma biomarkers performed similarly to models included Aβ alone in predicting dementia and CDR progression. However, improving Aβ model performance for composite cognitive score (CCS) decline, a proxy of dementia, was observed after including plasma monocyte chemoattractant protein 1 (MCP1) and growth differentiation factor 15 (GDF15) as covariates. Participants with abnormal Aβ, GDF15, and MCP1 presented higher CCS decline (worsening cognitive function) compared to their normal-biomarker counterparts (adjusted β [95% CI], − 0.21 [− 0.35 to − 0.06], p = 0.005). In conclusion, our study found limited added values of multi-biomarkers beyond the basic Aβ models for predicting clinically meaningful cognitive decline among non-demented older adults. However, a combined assessment of inflammatory and cellular stress status with Aβ pathology through measuring plasma biomarkers may improve the evaluation of cognitive performance. [ABSTRACT FROM AUTHOR]

Introduction: Potentially inappropriate medication prescribing (PIP) among older patients is associated with an increased risk of adverse events and hospitalization, and sometimes increased healthcare costs. Objective: The aim of this study was to explore the association between healthcare costs and PIP exposure among older patients. Methods: Analyses were conducted using data from the Multidomain Alzheimer Preventive Trial (MAPT). A computer algorithm was constructed to detect PIP based on various different explicit criteria-based tools, and the results were expressed in number of medication-related potential non-compliances (MRNCs). A prescription was considered potentially inappropriate if there were one or more MRNCs. We performed a cost analysis from the French National Health Insurance perspective, and also performed a multivariate analysis to identify the association between healthcare costs and PIP (number of MRNCs). Results: The computer algorithm analyzed medication prescribing from included patients (N = 1525 aged 75.3 ± 4.4 years; 64% women [n = 978]). PIP was associated with increased total healthcare costs and non-medication healthcare costs after adjusting for potential confounders. We also noted that healthcare costs tended to increase with the number of MRNCs. The mean additional healthcare costs were €517, €921, and €1669 per patient and year for patients with one or two MRNCs, three or four MRNCs, and five or more MRNCs, respectively, in comparison with patients with appropriate medication prescriptions. Conclusion: These observations led us to conclude that interventions focused on reducing PIP could result in savings. Trial Registration: ClinicalTrials.gov: NCT00672685. [ABSTRACT FROM AUTHOR]

Background: Monocyte Chemoattractant Protein-1 (MCP-1), a glial-derived chemokine, mediates neuroinflammation and may regulate memory outcomes among older adults. We aimed to explore the associations of plasma MCP-1 levels (alone and in combination with β-amyloid deposition—Aβ42/40) with overall and domain-specific cognitive evolution among older adults. Methods: Secondary analyses including 1097 subjects (mean age = 75.3 years ± 4.4; 63.8% women) from the Multidomain Alzheimer Preventive Trial (MAPT). MCP-1 (higher is worse) and Aβ42/40 (lower is worse) were measured in plasma collected at year 1. MCP-1 in continuous and as a dichotomy (values in the highest quartile (MCP-1+)) were used, as well as a dichotomy of Aβ42/40. Outcomes were measured annually over 4 years and included the following: cognitive composite z-score (CCS), the Mini-Mental State Examination (MMSE), and Clinical Dementia Rating (CDR) sum of boxes (overall cognitive function); composite executive function z-score, composite attention z-score, Free and Cued Selective Reminding Test (FCSRT - memory). Results: Plasma MCP-1 as a continuous variable was associated with the worsening of episodic memory over 4 years of follow-up, specifically in measures of free and cued delayed recall. MCP-1+ was associated with worse evolution in the CCS (4-year between-group difference: β = −0.14, 95%CI = −0.26, −0.02) and the CDR sum of boxes (2-year: β = 0.19, 95%CI = 0.06, 0.32). In domain-specific analyses, MCP-1+ was associated with declines in the FCSRT delayed recall sub-domains. In the presence of low Aβ42/40, MCP-1+ was not associated with greater declines in cognitive functions. The interaction with continuous biomarker values Aβ42/40× MCP-1 × time was significant in models with CDR sum of boxes and FCSRT DTR as dependent variables. Conclusions: Baseline plasma MCP-1 levels were associated with longitudinal declines in overall cognitive and episodic memory performance in older adults over a 4-year follow-up. How plasma MCP-1 interacts with Aβ42/40 to determine cognitive decline at different stages of cognitive decline/dementia should be clarified by further research. The MCP-1 association on cognitive decline was strongest in those with amyloid plaques, as measured by blood plasma Aβ42/40. [ABSTRACT FROM AUTHOR]

Key summary points: Aim: This study examined the bidirectional relationship between depressive symptoms and physical performance in community-dwelling older people with subjective memory complaints (SMCs). Findings: An independent effect of baseline physical performance on the change of depressive symptoms over time and an independent effect of baseline depressive symptoms on the change of physical performance over time were found. Message: Since depressive symptoms and physical performance had a bidirectional relationship, improvement of one may improve the other. Purpose: This study examined the bidirectional relationship between depressive symptoms and physical performance in community-dwelling older people with subjective memory complaints. Methods: Secondary analyses using data from the Multidomain Alzheimer Preventive Trial (MAPT) study were performed. The participants were 1679 subjects (female, 64.8%; mean age, 75.3 ± 4.4 years). The outcome measures were depressive symptoms assessed by the 15-item Geriatric Depression Scale (GDS) and physical performance assessed by the Short Physical Performance Battery (SPPB) and handgrip strength (HGS). All measurements were performed at baseline and at 6, 12, 24, and 36 months. The bidirectional relationships of GDS with SPPB and HGS were examined using mixed-effect regression analysis. Results: Baseline physical performance was significantly associated with a decreased GDS score (SPPB score: β = − 0.210, 95% confidence interval [CI], − 0.283 to − 0.137; HGS: β = − 0.038, 95% CI − 0.056 to − 0.019). The baseline GDS score was significantly associated with decreased physical performance (SPPB score: β = − 0.082, 95% CI − 0.107 to − 0.056; HGS: β = − 0.261, 95% CI − 0.370 to − 0.152). Conclusion: Since depressive symptoms and physical performance had a bidirectional relationship, prevention or improvement of decreased physical performance could play a role in reducing depressive symptoms, and addressing depressive symptoms may play a role in improving physical performance. Trial registration number: NCT01513252. [ABSTRACT FROM AUTHOR]

Neurofilament light chain (NfL) has been associated with cognitive status in multiple neurodegenerative conditions. Studies about plasma NfL and cognitive decline in older adults are still limited. 504 older adults (median age 75 years) who expressed memory complaints were selected from the Multidomain Alzheimer's Preventive Trial (MAPT) and were classified as normal cognition (NC) or mild cognitive impairment (MCI). Cognitive functions were measured as mini mental state examination (MMSE) and composite cognitive score (CCS) over a 4-year period. Plasma NfL was measured at the first or the second year of the MAPT. Mixed-effects linear models were performed to evaluate cross-sectional and longitudinal associations. In the whole population, higher plasma NfL was cross-sectionally associated with lower cognitive functions (MMSE: β = − 0.007, 95% CI [− 0.013, − 0.001]; CCS: β = − 0.003, 95% CI [− 0.006, − 0.001]). In adults with MCI, but not NC, higher plasma NfL was associated with lower CCS at the cross-sectional level (β = − 0.003, 95% CI [− 0.005, − 0.0002]). The upper quartile NfL group further demonstrated more over time decline in CCS (β = − 0.07, 95% CI [− 0.12, − 0.01]) under the MCI status. Plasma NfL can be a promising biomarker of progressive cognition decline in older adults with MCI. [ABSTRACT FROM AUTHOR]

BACKGROUND: Cross‐sectional associations have been found between frail individuals and worse white matter (WM) integrity. However, the prospective association between WM integrity and frailty is still unclear. Our objectives were to measure associations between WM integrity using diffusion tensor imaging (DTI) and the 5‐year worsening of frailty in community‐dwelling older adults. DESIGN: Secondary analysis of the randomized controlled Multidomain Alzheimer Preventive Trial (MAPT). SETTING: Thirteen memory centers in France and Monaco between 2008 and 2011. PARTICIPANTS: Participants (mean age = 74.7 ± 3.9 years) with no dementia at baseline who had functional magnetic resonance imaging performed as part of the MAPT study (n = 227). MEASUREMENTS: Fractional anisotropy and mean diffusivity (MD), axial diffusivity (AxD), and radial diffusivity (RD) were acquired for 10 different brain regions. Frailty was assessed by the Fried frailty phenotype (score from 0 to 5, higher is worse) at up to seven time points for 5 years. Mixed effect ordinal logistic regression model was used to assess the prospective association between DTI parameters (independent variables) and frailty (dependent variable). All the analyses were adjusted for age, sex, baseline total intracranial volume, and the presence of one of the following cardiovascular risk factors (hypertension, diabetes, and/or hypercholesterolemia). RESULTS: A statistically significant association was found between the RD, AxD, and MD for different brain regions (anterior limb of internal capsule, external capsule, posterior corona radiata, posterior thalamic radiation, superior corona radiata, superior frontal occipital fasciculus, and superior longitudinal fasciculus) and worsening of frailty over 5 years after adjusting for multiple comparisons. CONCLUSIONS: This is the first study to show that WM integrity is associated with frailty in older adults. The mechanisms related to these results require further investigation. J Am Geriatr Soc 68:1050–1055, 2020 [ABSTRACT FROM AUTHOR]

Background: Recruitment is often a bottleneck in secondary prevention trials in Alzheimer disease (AD). Furthermore, screen-failure rates in these trials are typically high due to relatively low prevalence of AD pathology in individuals without dementia, especially among cognitively unimpaired. Prescreening on AD risk factors may facilitate recruitment, but the efficiency will depend on how these factors link to participation rates and AD pathology. We investigated whether common AD-related factors predict trial-ready cohort participation and amyloid status across different prescreen settings. Methods: We monitored the prescreening in four cohorts linked to the European Prevention of Alzheimer Dementia (EPAD) Registry (n = 16,877; mean ± SD age = 64 ± 8 years). These included a clinical cohort, a research in-person cohort, a research online cohort, and a population-based cohort. Individuals were asked to participate in the EPAD longitudinal cohort study (EPAD-LCS), which serves as a trial-ready cohort for secondary prevention trials. Amyloid positivity was measured in cerebrospinal fluid as part of the EPAD-LCS assessment. We calculated participation rates and numbers needed to prescreen (NNPS) per participant that was amyloid-positive. We tested if age, sex, education level, APOE status, family history for dementia, memory complaints or memory scores, previously collected in these cohorts, could predict participation and amyloid status. Results: A total of 2595 participants were contacted for participation in the EPAD-LCS. Participation rates varied by setting between 3 and 59%. The NNPS were 6.9 (clinical cohort), 7.5 (research in-person cohort), 8.4 (research online cohort), and 88.5 (population-based cohort). Participation in the EPAD-LCS (n = 413 (16%)) was associated with lower age (odds ratio (OR) age = 0.97 [0.95–0.99]), high education (OR = 1.64 [1.23–2.17]), male sex (OR = 1.56 [1.19–2.04]), and positive family history of dementia (OR = 1.66 [1.19–2.31]). Among participants in the EPAD-LCS, amyloid positivity (33%) was associated with higher age (OR = 1.06 [1.02–1.10]) and APOE ɛ4 allele carriership (OR = 2.99 [1.81–4.94]). These results were similar across prescreen settings. Conclusions: Numbers needed to prescreen varied greatly between settings. Understanding how common AD risk factors link to study participation and amyloid positivity is informative for recruitment strategy of studies on secondary prevention of AD. [ABSTRACT FROM AUTHOR]

Objective: To determine whether brain amyloid burden in elderly patients with narcolepsy type 1 (NT1) is lower than in controls, and to assess in patients with NT1 the relationships between amyloid burden, cerebral spinal fluid (CSF) markers of Alzheimer disease (AD), CSF orexin-A, and cognitive profile.Methods: Cognitive and 18 F-florbetapir positron emission tomography (PET) data were compared in patients with NT1 aged ≥ 65 years (n = 23) and in age- and sex-matched controls free of clinical dementia selected from the Alzheimer's Disease Neuroimaging Initiative (ADNI; n = 69) and the Multi-Domain Intervention Alzheimer's Prevention Trial (MAPT-18F AV45-PET; n = 23) cohorts. The standardized uptake values (SUVs) of the cortical retention index for 6 regions of interest were computed and averaged to create a mean SUV ratio normalized to 3 subcortical reference regions (cerebellum, pons, and a composite region). A cortical/cerebellum SUV ratio ≥ 1.17 defined positive PET amyloid.Results: Lower cortical amyloid burden was observed in the NT1 than in the ADNI and MAPT-AV45 groups (mean cortical/cerebellum SUV ratios = 0.95 ± 0.15, 1.11 ± 0.18 [p < 0.0001], and 1.14 ± 0.17 [p = 0.0005], respectively). Similar results were obtained with all subcortical reference regions and for all cortical regions of interest, except cingulum. Only 1 patient with NT1 (4.4%) had positive PET amyloid compared with 27.5% in the ADNI and 30.4% in the MAPT-AV45 group. In the NT1 group, cortical or regional amyloid load was not associated with CSF orexin-A, CSF AD biomarkers, or neuropsychological profile.Interpretation: Lower brain amyloid burden, assessed by 18 F-florbetapir PET, in patients with NT1 suggests delayed appearance of amyloid plaques. ANN NEUROL 2019;85:74-83. [ABSTRACT FROM AUTHOR]

Omega-3 (n-3) and 6 (n-6) polyunsaturated fatty acids (PUFAs) have been associated with reduced cognitive decline in observational studies. Hence, we examined the cross-sectional associations between cortical β-amyloid (Aβ) and erythrocyte membrane PUFAs in 61 non-demented elderly individuals reporting subjective memory complaints from the Multidomain Alzheimer Preventive Trial placebo arm. Cortical-to-cerebellar standard uptake value ratios were obtained using [18F] florbetapir positron emission tomography. Fatty acids were measured in erythrocyte membranes by gas chromatography. Associations were explored using adjusted multiple linear regression models and were considered significant at p ≤ 0.005 after correction for multiple testing (10 comparisons). We found no significant associations between cortical Ab and erythrocyte membrane PUFAs. The associations closest to significance after adjustment were those between Ab and erythrocyte membrane arachidonic acid (without apolipoprotein E status adjustment: B-coefficient, 0.03; CI, 0.01, 0.05; p = 0.02. Including Apolipoprotein E adjustment: B-coefficient, 0.03; CI, 0.00, 0.06; p = 0.04) and Ab and erythrocyte membrane linoleic acid (without apolipoprotein E status adjustment: B-coefficient, 0.02; CI, 0.04, 0.00; p = 0.02. Including Apolipoprotein E adjustment: B-coefficient, 0.02; CI, 0.04, 0.00; p = 0.09). Furthermore, the association between Aβ and erythrocyte membrane arachidonic acid seemed to be specific to Apolipoprotein E ε4 non-carriers (B-coefficient 0.03, CI: 0.00, 0.06, p = 0.03, n = 36). In contrast, no association was found between Aβ and erythrocyte membrane linoleic acid in Apolipoprotein E ε4 stratified analysis. Investigating the relationships between Aβ and PUFAs longitudinally would provide further evidence as to whether fatty acids, particularly arachidonic acid and linoleic acid, might modulate cognition through Aβ-dependent mechanisms. [ABSTRACT FROM AUTHOR]

Objectives To examine the associations between amyloid- β brain deposition and physical activity ( PA) in elderly adults without dementia and to investigate whether the association has a dose-response relationship. Design Cross-sectional study. Setting French community-dwelling people. Participants Elderly adults with normal or mildly impaired cognition (mean age 74.7 ± 4.2; 60.4% female) with available information on current self-reported PA and amyloid- β brain deposition measured using positron emission tomography ( PET) using the PET-ligand florbetapir F 18 (n = 268). Measurements A standardized uptake value ratio ( SUVR) was obtained for each subject. Participants were divided according to amyloid plaque cortical retention defined according to a SUVR cutoff of 1.10 ( SUVR+ vs SUVR−). Results Bivariate and multivariate analyses showed that PA was not significantly associated with SUVR. SUVR+ and SUVR− participants did not differ in terms of volume (continuous PA variables) and levels (categorical PA variables) of PA. PA was not correlated with SUVR in apolipoprotein E ε4 carriers or noncarriers. PA was not associated with cognitive function. Conclusion Although PA protects against dementia, there is no solid evidence that this protection involves a reduction in amyloid- β brain deposition. Further studies are needed to determine whether PA (ideally measured at several time-points using objective measures) is involved in the pathophysiology of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

In a previous report, we showed vitamin K to preferentially accumulate in brain regions rich in white matter and to positively correlate with certain sphingolipids. In rodents, pharmacological vitamin K deficiency has resulted in behavioral perturbations. To gain insight on the role of vitamin K status on brain function, we investigated learning abilities IMorris water maze), motor activity (open field), and anxiety (elevated plus mazel in distinct groups of 6-, 1 2-, and 20-mo-old female Sprague-Dawley rats that had been fed diets containing low (L; ∼80 μg/kg diet), adequate (A; ∼500 μg/kg diet), or high (H; ∼2000 μg/kg diet) levels of phylloquinone (μg/kg diet; n = 9-12/diet) since weaning. In 20-mo-old rats, sphingolipids (cerebroside, sulfatide, sphingomyelin, ceramide, and gangliosides), phylloquinone, and menaquinone-4 were also assessed in cerebellum, midbrain, pons medulla, striatum, and hippocampus. Lifetime consumption of a low-vitamin K diet resulted in cognitive deficits in the 20-mo-old rats, with those in the L group having longer latencies than those in the H group )P < 0.05); this was associated with higher concentrations of ceramides in the hippocampus IP < 0.05) and lower gangliosides in the pons medulla and midbrain (P< 0.05). The low-vitamin K diet did not affect cognition at 6 and 12 mo of age, nor did it affect motor activity or anxiety at any age. Although much remains to be elucidated about the mechanism of action of vitamin K in cognition, this report points to vitamin K as an important nutritional factor contributing to cognitive health during aging. [ABSTRACT FROM AUTHOR]

The effect of a standard diet providing essential fatty acids enriched in fish oil or palm oil was studied in young, mature and old mice. Two groups of pregnant and lactating OF1 mice were fed on diets with or without high levels of long-chain n-3 polyunsaturated fatty acids. Offspring were maintained on these diets after weaning. The litter size did not differ. The weight increased more quickly in fish-oil-fed mice than palm-oil-fed mice. The fish-oil diet induced a significant increase in exploratory activity in young mice which was not found in mature and old mice. The level of locomotor activity was significantly higher in young, no different in mature, and lower in old fish-oil-fed mice than in controls. Habituation, the simpler form of learning, occurred to the same extent in the two diet groups. For the place learning protocol of the Morris water maze there was no difference between the two diet groups; however, in the probe trial, the mature fish-oil-fed mice remembered the situation well compared with the control mice. In the active avoidance test, on the first day of acquisition the young fish-oil-fed mice made more avoidances than control mice, whereas in contrast, mature and old-fish-fed mice made less avoidances than control mice. These results suggest a positive effect on arousal and learning ability of a diet enriched in long chain n-3 polyunsaturated fatty acids in young mice and a detrimental effect in old mice. [ABSTRACT FROM PUBLISHER]

Background: Cognition is closely associated with physical function. Although high brain amyloid-β (Aβ) deposition and neurofilament light chain (NfL) are associated with cognitive and gait speed decline, relationships of combined plasma Aβ and NfL profiles with cognitive and physical functions in older adults remain unknown. The research aim of this study was to investigate the prospective associations of combined plasma Aβ and NfL profiles with cognitive and physical functions in older adults. Methods: Participants (n = 452, aged 76 ± 5 years) who had both plasma Aβ and NfL data collected from the Multidomain Alzheimer's Preventive Trial (MAPT, May 2008 to April 2016) were included in the current study. These participants were from four MAPT groups (multidomain interventions [physical activity and nutritional counselling, and cognitive training], omega-3 supplementation, multidomain plus omega-3 supplementation and control group) and had received a 3-year intervention, followed by a 2-year observational follow-up. Cognitive function was evaluated as Mini-Mental State Examination and composite cognitive score (CCS, a mean Z-score combining four cognitive tests). Physical function was evaluated as gait speed (4-m usual-pace walk test) and chair-stand time (5-time maximal chair-stand test). Cognitive and physical function data measured at the time of and after blood Aβ and NfL tests were used for analysis. Participants with plasma Aβ42/Aβ40 ratios lower than 0.107 and NfL levels greater than 93.04 pg/ml were classified as Aβ+ and NfL+. Multivariable regressions and mixed-effects linear models were used for the analysis. Results: At the cross-sectional level, no significant association was found between Aβ+NfL+ and cognitive or physical function after controlling for age, sex, body mass index, education level and MAPT group. Evaluating longitudinal changes, participants with Aβ+NfL+ had greater annual declines in the CCS (β = − 0.11, 95%CI [− 0.17, − 0.05]) and gait speed (β = − 0.03, 95%CI [− 0.05, − 0.005]). After adjusting for APOE ɛ4 genotype, Aβ+NfL+ was associated with a greater decline only in the CCS (β = − 0.09, 95%CI [− 0.15, − 0.02]). Conclusions: Combined low plasma Aβ42/Aβ40 ratio and high plasma NfL level was associated with greater declines in cognition and gait speed over time, providing further evidence of the links between cognitive and physical function. Trial registration: www.clinicaltrials.gov [NCT00672685]. [ABSTRACT FROM AUTHOR]