The serum metabolome mediates the concert of diet, exercise, and neurogenesis, determining the risk for cognitive decline and dementia

Introduction: Diet and exercise influence the risk of cognitive decline (CD) and dementia through the food metabolome and exercise-triggered endogenous factors, which use the blood as a vehicle to communicate with the brain. These factors might act in concert with hippocampal neurogenesis (HN) to shape CD and dementia. Methods: Using an in vitro neurogenesis assay, we examined the effects of serum samples from a longitudinal cohort (n = 418) on proxy HN readouts and their association with future CD and dementia across a 12-year period. Results: Altered apoptosis and reduced hippocampal progenitor cell integrity were associated with exercise and diet and predicted subsequent CD and dementia. The effects of exercise and diet on CD specifically were mediated by apoptosis. Discussion: Diet and exercise might influence neurogenesis long before the onset of CD and dementia. Alterations in HN could signify the start of the pathological process and potentially represent biomarkers for CD and dementia

Nutritional concerns, health and survival in old age

The ageing process is—apart from chance or good luck—not only influenced by factors intrinsic to the individual, but also by extrinsic factors that include environmental and lifestyle variables. This paper deals with the epidemiological evidence for the role of dietary patterns and key nutritional concerns in relation to survival and ageing related disorders that present themselves in later life. Dietary patterns, such as the Mediterranean diet, characterized by mainly plant foods including protective factors e.g. vegetables, nuts and monounsaturated fatty acids and excluding harmful factors e.g. trans-fatty acids and foods with a high glycemic factor, appear to be relevant even in old age. Specific nutritional concerns focus on general undernutrition, vitamin D and vitamin B12. Prevalence of nutritional inadequacies, diagnostic criteria, causes and health consequences are described. The paper ends with recommendations for guidance on healthy diets for elderly people. An important challenge should be research to further expand the knowledge base, acknowledging the complexity of the ageing process and integrating different dimensions of research into human healthy ageing in properly designed studies. In the mean time reversing poor adherence to existing guidelines for a healthy diet remains a first challenge in public health nutritional practices

Association between IgM Anti-Herpes Simplex Virus and Plasma Amyloid-Beta Levels

OBJECTIVE: Herpes simplex virus (HSV) reactivation has been identified as a possible risk factor for Alzheimer's disease (AD) and plasma amyloid-beta (Aβ) levels might be considered as possible biomarkers of the risk of AD. The aim of our study was to investigate the association between anti-HSV antibodies and plasma Aβ levels. METHODS: The study sample consisted of 1222 subjects (73.9 y in mean) from the Three-City cohort. IgM and IgG anti-HSV antibodies were quantified using an ELISA kit, and plasma levels of Aβ(1-40) and Aβ(1-42) were measured using an xMAP-based assay technology. Cross-sectional analyses of the associations between anti-HSV antibodies and plasma Aβ levels were performed by multi-linear regression. RESULTS: After adjustment for study center, age, sex, education, and apolipoprotein E-e4 polymorphism, plasma Aβ(1-42) and Aβ(1-40) levels were specifically inversely associated with anti-HSV IgM levels (β = -20.7, P=0.001 and β = -92.4, P=0.007, respectively). In a sub-sample with information on CLU- and CR1-linked SNPs genotyping (n=754), additional adjustment for CR1 or CLU markers did not modify these associations (adjustment for CR1 rs6656401, β = -25.6, P=0.002 for Aβ(1-42) and β = -132.7, P=0.002 for Aβ(1-40;) adjustment for CLU rs2279590, β = -25.6, P=0.002 for Aβ(1-42) and β = -134.8, P=0.002 for Aβ(1-40)). No association between the plasma Aβ(1-42)-to-Aβ(1-40) ratio and anti-HSV IgM or IgG were evidenced. CONCLUSION: High anti-HSV IgM levels, markers of HSV reactivation, are associated with lower plasma Aβ(1-40) and Aβ(1-42) levels, which suggest a possible involvement of the virus in the alterations of the APP processing and potentially in the pathogenesis of AD in human

Fish, docosahexaenoic acid and Alzheimer’s disease

Cognitive decline in the elderly, particularly Alzheimer’s disease (AD), is a major socio-economic and healthcare concern. We review here the literature on one specific aspect of diet affecting AD, that of the ω3 fatty acids, particularly the brain’s principle ω3 fatty acid – docosahexaenoic acid (DHA). DHA has deservedly received wide attention as a nutrient supporting both optimal brain development and for cardiovascular health. Our aim here is to critically assess the quality of the present literature as well as the potential of ω3 fatty acids to treat or delay the onset of AD. We start with a brief description of cognitive decline in the elderly, followed by an overview of well recognized biological functions of DHA. We then turn to epidemiological studies, which are largely supportive of protective effects of fish and DHA against risk of AD. However, biological studies, including blood and brain DHA analyses need careful interpretation and further investigation, without which the success of clinical trials with DHA may continue to struggle. We draw attention to some of the methodological issues that need resolution as well as an emerging mechanism that may explain how DHA could be linked to protecting brain function in the elderly

Dietary patterns in French home-living older adults: Results from the PRAUSE study

International audienc

Dietary patterns and 12-year risk of frailty: Results from the three-city Bordeaux study

Objective: To analyze the association between dietary patterns and the 12-year risk of frailty and its components in community-dwelling elderly French adults. Design: A prospective cohort study. Setting: The Bordeaux sample of the Three-City Study. Participants: A total of 972 initially nonfrail nondemented participants (336 men and 636 women) aged 73 years on average, re-examined at least once over 12 years. Measurements: Five sex-specific dietary clusters were previously derived at baseline. Frailty incident to the baseline visit was defined as having at least three out of the following 5 criteria: unintentional weight loss, exhaustion, low energy expenditure, slowness, and muscle weakness. Multivariate Cox proportional hazard models were used to assess the association between dietary clusters and the risk of frailty and its components. Results: In total, 78 men for 3719 person-years and 221 women for 7027 person-years became frail over the follow-up. In multivariate analyses, men in the “pasta” pattern and women in the “biscuits and snacking” pattern had a significantly higher risk of frailty compared with those in the “healthy” pattern [hazard ratio (HR) 2.2; 95% confidence interval (CI) 1.1–4.4 and HR 1.8; 95% CI 1.2–2.8, respectively; P = .09 and P = .13 for the global test of significance of risk difference across clusters, respectively]. In men, “biscuits and snacking” and “pasta” patterns were significantly associated with higher risk for muscle weakness (HR 3.3; 95% CI 1.6–7.0 and HR 2.1; 95% CI 1.2–3.7, respectively; P = .003 for global test). Conclusions: This 12-year prospective population-based study suggests that some particular unhealthy dietary patterns may increase the risk of frailty in older adults.</p