Explore the vast range of titles available.

Background The Apolipoprotein E ε4 allele (i.e. ApoE4) is the strongest genetic risk factor for sporadic Alzheimer’s disease (AD). TREM2 (i.e. Triggering receptor expressed on myeloid cells 2) is a microglial transmembrane protein brain that plays a central role in microglia activation in response to AD brain pathologies. Whether higher TREM2-related microglia activity modulates the risk to develop clinical AD is an open question. Thus, the aim of the current study was to assess whether higher sTREM2 attenuates the effects of ApoE4-effects on future cognitive decline and neurodegeneration. Methods We included 708 subjects ranging from cognitively normal (CN, n  = 221) to mild cognitive impairment (MCI, n  = 414) and AD dementia ( n  = 73) from the Alzheimer’s disease Neuroimaging Initiative. We used linear regression to test the interaction between ApoE4-carriage by CSF-assessed sTREM2 levels as a predictor of longitudinally assessed cognitive decline and MRI-assessed changes in hippocampal volume changes (mean follow-up of 4 years, range of 1.7-7 years). Results Across the entire sample, we found that higher CSF sTREM2 at baseline was associated with attenuated effects of ApoE4-carriage (i.e. sTREM2 x ApoE4 interaction) on longitudinal global cognitive ( p  = 0.001, Cohen’s f 2  = 0.137) and memory decline ( p  = 0.006, Cohen’s f 2  = 0.104) as well as longitudinally assessed hippocampal atrophy ( p  = 0.046, Cohen’s f 2  = 0.089), independent of CSF markers of primary AD pathology (i.e. Aβ 1–42 , p-tau 181 ). While overall effects of sTREM2 were small, exploratory subanalyses stratified by diagnostic groups showed that beneficial effects of sTREM2 were pronounced in the MCI group. Conclusion Our results suggest that a higher CSF sTREM2 levels are associated with attenuated ApoE4-related risk for future cognitive decline and AD-typical neurodegeneration. These findings provide further evidence that TREM2 may be protective against the development of AD.

Women carry a higher burden of Alzheimer’s disease (AD) compared to men, which is not accounted entirely by differences in lifespan. To identify the mechanisms underlying this effect, we investigated sex-specific differences in the progression of familial AD in humans and in APPswe/PS1ΔE9 mice. Activity dependent protein translation and associative learning and memory deficits were examined in APPswe/PS1ΔE9 mice and wild-type mice. As a human comparator group, progression of cognitive dysfunction was assessed in mutation carriers and non-carriers from DIAN (Dominantly Inherited Alzheimer Network) cohort. Female APPswe/PS1ΔE9 mice did not show recall deficits after contextual fear conditioning until 8 months of age. Further, activity dependent protein translation and Akt1-mTOR signaling at the synapse were impaired in male but not in female mice until 8 months of age. Ovariectomized APPswe/PS1ΔE9 mice displayed recall deficits at 4 months of age and these were sustained until 8 months of age. Moreover, activity dependent protein translation was also impaired in 4 months old ovariectomized APPswe/PS1ΔE9 mice compared with sham female APPswe/PS1ΔE9 mice. Progression of memory impairment differed between men and women in the DIAN cohort as analyzed using linear mixed effects model, wherein men showed steeper cognitive decline irrespective of the age of entry in the study, while women showed significantly greater performance and slower decline in immediate recall (LOGIMEM) and delayed recall (MEMUNITS) than men. However, when the performance of men and women in several cognitive tasks (such as Wechsler’s logical memory) are compared with the estimated year from expected symptom onset (EYO) we found no significant differences between men and women. We conclude that in familial AD patients and mouse models, females are protected, and the onset of disease is delayed as long as estrogen levels are intact.

Resting state functional connectivity (rs-fMRI) is impaired early in persons who subsequently develop Alzheimer’s disease (AD) dementia. This impairment may be leveraged to aid investigation of the pre-clinical phase of AD. We developed a model that predicts brain age from resting state (rs)-fMRI data, and assessed whether genetic determinants of AD, as well as beta-amyloid (Aβ) pathology, can accelerate brain aging. Using data from 1340 cognitively unimpaired participants between 18–94 years of age from multiple sites, we showed that topological properties of graphs constructed from rs-fMRI can predict chronological age across the lifespan. Application of our predictive model to the context of pre-clinical AD revealed that the pre-symptomatic phase of autosomal dominant AD includes acceleration of functional brain aging. This association was stronger in individuals having significant Aβ pathology. Alzheimer’s disease has been associated with increased structural brain aging. Here the authors describe a model that predicts brain aging from resting state functional connectivity data, and demonstrate this is accelerated in individuals with pre-clinical familial Alzheimer’s disease.

INTRODUCTION We investigated the efficacy of a multidomain intervention (MI) via face‐to‐face and video communication platforms using a tablet personal computer application in patients with mild cognitive impairment (MCI). METHODS Three hundred participants with MCI and ≥ 1 modifiable dementia risk factor, aged 60‐85 years, were randomly assigned to either the MI group, who underwent a 24‐week intervention, or the control group, who received usual care. RESULTS The overall adherence rate to MI was 84.7%. The adjusted mean change from baseline at 24 weeks in the total scale index score of the repeatable battery for the assessment of neuropsychological status was 8.43 in the MI group and 4.26 in the control group (difference, 4.17; 95% confidence interval, 1.92‐6.43; p < 0.001). MI showed significant beneficial effects on cognition in both apolipoprotein E (APOE) ε4 carriers and noncarriers. DISCUSSION MI can exert beneficial effects on the cognition of patients with MCI. Trial Registration: ClinicalTrials.gov identifier: NCT05023057 Highlights Although the controls also demonstrated improved performance in cognition, multidomain interventions showed significantly greater benefits for cognition in MCI compared to the controls in a randomized controlled trial. Multidomain interventions improved depression and quality of life. Multidomain interventions significantly positively impacted cognition in both APOE ε4 carriers and noncarriers. Multidomain interventions may be more effective for amnestic than nonamnestic MCI.

BackgroundHigher docosahexaenoic acid (DHA) intake is inversely correlated with relative risk of Alzheimer’s disease. The potential benefits of DHA supplementation in people with mild cognitive impairment (MCI) have not been fully examined.ObjectiveOur study aimed to assess the effect of a 24-month DHA supplementation on cognitive function and amyloid beta (Aβ)-mediated autophagy in elderly subjects with MCI.MethodsThis was a randomised, double-blind, placebo-controlled trial in Tianjin, China. A total of 240 individuals with MCI were identified and randomly divided into intervention (DHA 2 g/day, n=120) and control (corn oil as placebo, n=120) groups. Cognitive function and blood Aβ-related biomarkers were measured at baseline, 6, 12, 18 and 24 months. Data were analysed using generalised estimating equation.ResultsA total of 217 participants (DHA: 109, placebo: 108) completed the trial. During the follow-up, scores of full-scale IQ, verbal IQ and subdomains of information and digit span were significantly higher in the intervention group than the convention group (p<0.05). In the intervention group, blood Aβ-42 level and expression of Aβ protein precursor mRNA were decreased (p<0.05), while Beclin-1 and LC3-II levels and expression of LC3-II mRNA were increased (p<0.05).ConclusionDaily oral DHA supplementation (2 g/day) for 24 months may improve cognitive function and change blood biomarker-related Aβ-mediated autophagy in people with MCI. Larger longer-term confirmatory studies are warranted.Trial registration numberChiCTR-IOR-15006058.

Cognitive training (CT) programs aim to improve cognitive performance and impede its decline. Thus, defining the characteristics of individuals who can benefit from these interventions is essential. Our objectives were to assess if the cognitive reserve (CR), APOE genotype (e4 carriers/non-carriers) and/or hippocampal volume might predict the effectiveness of a CT program. Participants were older adults without dementia (n = 226), randomized into parallel experimental and control groups. The assessment consisted of a neuropsychological protocol and additional data regarding total intracranial, gray matter, left/right hippocampus volume; APOE genotype; and Cognitive Reserve (CR). The intervention involved multifactorial CT (30 sessions, 90 min each), with an evaluation pre- and post-training (at six months); the control group simply following the center’s routine activities. The primary outcome measures were the change in cognitive performance and the predictors of change. The results show that APOE-e4 non-carriers (79.1%) with a larger left hippocampal volume achieved better gains in semantic verbal fluency (R 2  = .19). Subjects with a larger CR and a greater gray matter volume better improved their processing speed (R 2  = .18). Age was correlated with the improvement in executive functions, such that older age predicts less improvement (R 2  = .07). Subjects with a larger left hippocampal volume achieved more significant gains in general cognitive performance (R 2  = .087). In conclusion, besides the program itself, the effectiveness of CT depends on age, biological factors like genotype and brain volume, and CR. Thus, to achieve better results through a CT, it is essential to consider the different characteristics of the participants, including genetic factors. Trial registration : Trial retrospectively registered on January 29th, 2020—( ClinicalTrials.gov -NCT04245579).

A polygenic risk score (PRS) estimates an individual's genetic liability for diseases based on accumulated genetic variations. While the PRS has been shown to contribute to the prediction of dementia risk, its utility in predicting the effectiveness of multifactorial interventions to reduce the risk of dementia remains unclear. A genome-wide association study (GWAS) was conducted to identify dementia-related traits in the Japanese population. Subsequently, PRSs were constructed based on GWAS results using PRSice-2 software. The Japan-multimodal intervention trial for prevention of dementia (J-MINT) is an RCT to assess the effect of multi-domain interventions for subjects with mild cognitive impairment. The J-MINT samples were classified into high-risk and low-risk groups using the Japanese PRS. Within each risk group, cognitive function improvement due to the intervention was assessed using Fisher's exact test. We conducted a GWAS with 3962 AD cases and 4074 controls for 4,578,811 genetic markers that passed stringent quality control filters. The optimal PRS, composed of 12,818 SNPs and APOE status, was developed at a p-value threshold of 0.090, selected for its highest model fit with an R score of 0.023. Subsequently, the PRS classified 289 J-MINT samples into 99 high-risk and 190 low-risk groups. Individuals in the young-old group (aged <75 years) showed significant cognitive improvement through the intervention in the high-risk group; however, those in the old-old group (aged 75 years) did not demonstrate such potential in either risk group. While we have successfully developed a Japanese PRS with high predictive ability, it is important to note that our dataset is limited and relatively small. To achieve an accurate AD PRS for the Japanese population, further validation studies are necessary, involving a larger dataset or conducting a meta-analysis with another Japanese cohort. Additionally, our study highlights the potential utility of the PRS in screening subjects for cognitive improvement, especially for individuals with high PRS in the young-old group.

Background: The Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) was a 3-year, multicenter, randomized controlled trial to test the effects of the MIND diet on cognitive decline in 604 individuals at risk for Alzheimer’s dementia. Here, we describe the genotyping, imputation, and quality control (QC) procedures for the genetic data of trial participants. Methods: DNA was extracted from either whole blood or serum, and genotyping was performed using the Infinium Global Diversity Array. Established sample and SNP QC procedures were applied to the genotyping data, followed by imputation using the 1000 Genomes Phase 3 v5 reference panel. Results: Significant study-site, specimen type, and batch effects were observed. A total of 494 individuals of inferred European ancestry and 58 individuals of inferred African ancestry were included in the final imputed dataset. Evaluation of the imputed APOE genotype against gold-standard sequencing data showed high concordance (98.2%). We replicated several known genetic associations identified from previous genome-wide association studies, including SNPs previously linked to adiponectin (rs16861209, p = 1.5 × 10−5), alpha-linolenic acid (rs174547, p = 1.3 × 10−7), and alpha-tocopherol (rs964184, p = 0.003). Conclusions: This dataset represents the first genetic resource derived from a dietary intervention trial focused on cognitive outcomes. It enables investigation of genetic contributions to variability in cognitive response to the MIND diet and supports integrative analyses with other omics data types to elucidate the biological mechanisms underlying cognitive decline. These efforts may ultimately inform precision nutrition strategies to promote cognitive health.

BackgroundThe growing prevalence of dementia emphasizes the need for effective prevention strategies. Although the partial efficacy of multidomain interventions for dementia prevention has been demonstrated, understanding the characteristics of individuals who benefit most from these interventions is crucial for optimizing resource allocation. This study investigated the association between participants’ genetic backgrounds and the effectiveness of multidomain interventions for preventing dementia.MethodsThis study utilized data from the Japan-Multimodal Intervention Trial for the Prevention of Dementia (J-MINT), where older adults with mild cognitive impairment underwent 18 months of multidomain intervention. The intervention included exercise, nutrition, cognitive stimulation, social participation, and vascular risk management. Participants who completed the J-MINT intervention and had genetic data, including whole-genome sequencing (WGS), were analyzed. Using Japanese polygenic risk scores (PRSs) for Alzheimer’s disease, participants were stratified into high- and low-genetic-risk groups. Cognitive composite score (CPS) improvement rates at 6-, 12-, and 18-months were compared between intervention and control groups, with subgroup analyses performed by age (< 75 and ≥ 75 years). Additionally, a comprehensive variant analysis using WGS was conducted to identify genetic signals potentially associated with the intervention’s effectiveness.ResultsAmong 289 participants analyzed (168 aged < 75 years; 121 aged ≥ 75 years), 99 were classified into the high-risk PRS group (56 intervention, 43 control) and 190 into the low-risk PRS group (92 intervention, 98 control). For participants aged ≥ 75 years, no statistically significant differences in CPS improvement rates were observed between the intervention and control groups, regardless of PRS classification. However, in participants aged < 75, those in the high-risk PRS group showed significant CPS improvement at the 6-month follow-up. Additionally, analysis of 9,978,605 genetic variants identified two loci, ID3 and LMO1 (rs2067053 and rs201082658), with suggestive associations (P < 1 × 10⁻4) to reduced intervention effectiveness.ConclusionsThis study highlighted the utility of PRS in predicting cognitive improvement following multidomain interventions and identified genetic variants that may influence the intervention's effectiveness. The findings provide a valuable foundation for personalized dementia prevention strategies.

Objective Previous research has indicated cognitive decline (CD) among testicular cancer patients (TCPs), even in the absence of chemotherapy, but little is known about the underlying pathophysiology. The present study assessed changes in cognitive functions and structural brain connectomes in TCPs and explored the associations between cognitive changes and endocrine status and hypothesized risk genotypes. Methods Thirty‐eight newly orchiectomized TCPs and 21 healthy controls (HCs) comparable to TCPs in terms of age and years of education underwent neuropsychological testing, structural MRI, and a biological assessment at baseline and 6 months later. Cognitive change was assessed with a neuropsychological test battery and determined using a standardized regression‐based approach, with substantial change defined as z‐scores ≤−1.64 or ≥1.64. MRI scans and graph theory were used to evaluate changes in structural brain connectomes. The associations of cognitive changes with testosterone levels, androgen receptor gene (AR) CAG repeat length, and genotypes (APOE, COMT, and BDNF) were explored. Results Compared with HCs, TCPs showed higher rates of substantial decline on processing speed and visuospatial ability and higher rates of substantial improvement on verbal recall and visuospatial learning (p < 0.05; OR = 8.15–15.84). Brain network analysis indicated bilateral thalamic changes in node degree in HCs, but not in TCPs (p < 0.01). In TCPs, higher baseline testosterone levels predicted decline in verbal memory (p < 0.05). No effects were found for AR CAG repeat length, APOE, COMT, or BDNF. Conclusions The present study confirms previous findings of domain‐specific CD in TCPs following orchiectomy, but also points to domain‐specific improvements. The results do not indicate changes in brain connectomes or endocrine status to be the main drivers of CD. Further studies evaluating the mechanisms underlying CD in TCPs, including the possible role of the dynamics of the hypothalamic–pituitary–gonadal axis, are warranted. The present study confirms previous findings of domain‐specific cognitive decline in testicular cancer patients following orchiectomy, but also points to domain‐specific improvements. The results do not indicate changes in brain connectomes or endocrine status to be the main drivers of cognitive changes.