Age-related networks of regional covariance in MRI gray matter: Reproducible multivariate patterns in healthy aging

AbstractTo evaluate the effect of aging, intra- and intersession repeatability and regional scotopic sensitivities in healthy and age-related macular degeneration (AMD) eyes. Intra- and intersession agreement and effect of age was measured in healthy individuals. The mean sensitivity (MS) and pointwise retinal sensitivities (PWS) within the central 24° with 505 nm (cyan) and 625 nm (red) stimuli were evaluated in 50 individuals (11 healthy and 39 AMD eyes). The overall intra- and intersession had excellent reliability (intraclass correlation coefficient, ICC > 0.90) and tests were highly correlated (Spearman rs = 0.75–0.86). Eyes with subretinal drusenoid deposit (SDD) had reduced PWS centrally, particularly at inferior and nasal retinal locations compared with controls and intermediate AMD (iAMD) without SDD. There was no difference in MS or PWS at any retinal location between iAMD without SDD and healthy individuals nor between iAMD with SDD and non-foveal atrophic AMD groups. Eyes with SDD have reduced rod function compared to iAMD without SDD and healthy eyes, but similar to eyes with non-foveal atrophy. Our results highlight rod dysfunction is not directly correlated with drusen load and SDD location.

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Age-related differences in multiple measures of white matter integrity: A diffusion tensor imaging study of healthy aging

Human Brain Mapping ◽

10.1002/hbm.20872 ◽

2009 ◽

pp. NA-NA ◽

Cited By ~ 67

Author(s):

Ilana J. Bennett ◽

David J. Madden ◽

Chandan J. Vaidya ◽

Darlene V. Howard ◽

James H. Howard

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Healthy Aging ◽

Diffusion Tensor ◽

Imaging Study ◽

White Matter Integrity ◽

Multiple Measures ◽

Age Related ◽

Diffusion Tensor Imaging Study

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Nutrition for Older Athletes: Focus on Sex-Differences

Nutrients ◽

10.3390/nu13051409 ◽

2021 ◽

Vol 13 (5) ◽

pp. 1409

Author(s):

Barbara Strasser ◽

Dominik Pesta ◽

Jörn Rittweger ◽

Johannes Burtscher ◽

Martin Burtscher

Keyword(s):

Sex Differences ◽

Exercise Training ◽

Role Model ◽

Healthy Aging ◽

Endurance Performance ◽

Metabolic Efficiency ◽

Older Athletes ◽

Age Related ◽

Masters Athletes ◽

Physical Capacities

Regular physical exercise and a healthy diet are major determinants of a healthy lifespan. Although aging is associated with declining endurance performance and muscle function, these components can favorably be modified by regular physical activity and especially by exercise training at all ages in both sexes. In addition, age-related changes in body composition and metabolism, which affect even highly trained masters athletes, can in part be compensated for by higher exercise metabolic efficiency in active individuals. Accordingly, masters athletes are often considered as a role model for healthy aging and their physical capacities are an impressive example of what is possible in aging individuals. In the present review, we first discuss physiological changes, performance and trainability of older athletes with a focus on sex differences. Second, we describe the most important hormonal alterations occurring during aging pertaining regulation of appetite, glucose homeostasis and energy expenditure and the modulatory role of exercise training. The third part highlights nutritional aspects that may support health and physical performance for older athletes. Key nutrition-related concerns include the need for adequate energy and protein intake for preventing low bone and muscle mass and a higher demand for specific nutrients (e.g., vitamin D and probiotics) that may reduce the infection burden in masters athletes. Fourth, we present important research findings on the association between exercise, nutrition and the microbiota, which represents a rapidly developing field in sports nutrition.

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A metabolomic aging clock using human CSF

The Journals of Gerontology Series A ◽

10.1093/gerona/glab212 ◽

2021 ◽

Author(s):

Nathan Hwangbo ◽

Xinyu Zhang ◽

Daniel Raftery ◽

Haiwei Gu ◽

Shu-Ching Hu ◽

...

Keyword(s):

Cerebrospinal Fluid ◽

Healthy Aging ◽

Prediction Models ◽

Mass Spectrometry Analysis ◽

Chronological Age ◽

Healthy Human ◽

Missing Data Imputation ◽

Spectrometry Analysis ◽

Residual Variation ◽

Age Related

Abstract Quantifying the physiology of aging is essential for improving our understanding of age-related disease and the heterogeneity of healthy aging. Recent studies have shown that in regression models using “-omic” platforms to predict chronological age, residual variation in predicted age is correlated with health outcomes, and suggest that these “omic clocks” provide measures of biological age. This paper presents predictive models for age using metabolomic profiles of cerebrospinal fluid from healthy human subjects, and finds that metabolite and lipid data are generally able to predict chronological age within 10 years. We use these models to predict the age of a cohort of subjects with Alzheimer’s and Parkinson’s disease and find an increase in prediction error, potentially indicating that the relationship between the metabolome and chronological age differs with these diseases. However, evidence is not found to support the hypothesis that our models will consistently over-predict the age of these subjects. In our analysis of control subjects, we find the carnitine shuttle, sucrose, biopterin, vitamin E metabolism, tryptophan, and tyrosine to be the most associated with age. We showcase the potential usefulness of age prediction models in a small dataset (n = 85), and discuss techniques for drift correction, missing data imputation, and regularized regression, which can be used to help mitigate the statistical challenges that commonly arise in this setting. To our knowledge, this work presents the first multivariate predictive metabolomic and lipidomic models for age using mass spectrometry analysis of cerebrospinal fluid.

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Aging of the Retina: Molecular and Metabolic Turbulences and Potential Interventions

Annual Review of Vision Science ◽

10.1146/annurev-vision-100419-114940 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Laura Campello ◽

Nivedita Singh ◽

Jayshree Advani ◽

Anupam K. Mondal ◽

Ximena Corso-Diaz ◽

...

Keyword(s):

Healthy Aging ◽

Cell Types ◽

Lifestyle Changes ◽

Annual Review ◽

Past Century ◽

Publication Date ◽

Vision Science ◽

Human Lifespan ◽

Cellular Events ◽

Age Related

Multifaceted and divergent manifestations across tissues and cell types have curtailed advances in deciphering the cellular events that accompany advanced age and contribute to morbidities and mortalities. Increase in human lifespan during the past century has heightened awareness of the need to prevent age-associated frailty of neuronal and sensory systems to allow a healthy and productive life. In this review, we discuss molecular and physiological attributes of aging of the retina, with a goal of understanding age-related impairment of visual function. We highlight the epigenome–metabolism nexus and proteostasis as key contributors to retinal aging and discuss lifestyle changes as potential modulators of retinal function. Finally, we deliberate promising intervention strategies for promoting healthy aging of the retina for improved vision. Expected final online publication date for the Annual Review of Vision Science, Volume 7 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

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A Correlational Study between Microstructural White Matter Properties and Macrostructural Gray Matter Volume Across Normal Ageing: Conjoint DTI and VBM Analysis

Magnetic Resonance Insights ◽

10.1177/1178623x18799926 ◽

2018 ◽

Vol 11 ◽

pp. 1178623X1879992 ◽

Cited By ~ 4

Author(s):

Vikas Pareek ◽

VP Subramanyam Rallabandi ◽

Prasun K Roy

Keyword(s):

White Matter ◽

Life Span ◽

Fractional Anisotropy ◽

Gray Matter ◽

Healthy Aging ◽

Gray Matter Volume ◽

Mean Diffusivity ◽

Radial Diffusivity ◽

Axial Diffusivity ◽

Matter Volume

We investigate the relationship between Gray matter’s volume vis-a-vis White matter’s integrity indices, such Axial diffusivity, Radial diffusivity, Mean diffusivity, and Fractional anisotropy, in individuals undergoing healthy aging. We investigated MRI scans of 177 adults across 20 to 85 years. We used Voxel-based morphometry, and FDT-FSL analysis for estimation of Gray matter volume and White matter’s diffusion indices respectively. Across the life span, we observed an inter-relationship between the Gray matter and White matter, namely that both Axial diffusivity and Mean Diffusivity show strong correlation with Gray matter volume, along the aging process. Furthermore, across all ages the Fractional anisotropy and Mean diffusivity are found to be significantly reduced in females when compared to males, but there are no significant gender differences in Axial Diffusivity and Radial diffusivity. We conclude that for both genders across all ages, the Gray matter’s Volume is strongly correlated with White matter’s Axial Diffusivity and Mean Diffusivity, while being weakly correlated with Fractional Anisotropy. Our study clarifies the multi-scale relationship in brain tissue, by elucidating how the White matter’s micro-structural parameters influences the Gray matter’s macro-structural characteristics, during healthy aging across the life-span.

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Inhibition of 11β-HSD1 Ameliorates Cognition and Molecular Detrimental Changes after Chronic Mild Stress in SAMP8 Mice

Pharmaceuticals ◽

10.3390/ph14101040 ◽

2021 ◽

Vol 14 (10) ◽

pp. 1040

Author(s):

Dolors Puigoriol-Illamola ◽

Júlia Companys-Alemany ◽

Kris McGuire ◽

Natalie Z. M. Homer ◽

Rosana Leiva ◽

...

Keyword(s):

Stress Responses ◽

Healthy Aging ◽

Molecular Mechanisms ◽

Chronic Mild Stress ◽

Mild Stress ◽

Cognitive Improvement ◽

Age Related ◽

Mtorc1 Signaling ◽

Cognitive Disturbances ◽

Samp8 Mice

Impaired glucocorticoid (GC) signaling is a significant factor in aging, stress, and neurodegenerative diseases such as Alzheimer’s disease. Therefore, the study of GC-mediated stress responses to chronic moderately stressful situations, which occur in daily life, is of huge interest for the design of pharmacological strategies toward the prevention of neurodegeneration. To address this issue, SAMP8 mice were exposed to the chronic mild stress (CMS) paradigm for 4 weeks and treated with RL-118, an 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) inhibitor. The inhibition of this enzyme is linked with a reduction in GC levels and cognitive improvement, while CMS exposure has been associated with reduced cognitive performance. The aim of this project was to assess whether RL-118 treatment could reverse the deleterious effects of CMS on cognition and behavioral abilities and to evaluate the molecular mechanisms that compromise healthy aging in SAMP8 mice. First, we confirmed the target engagement between RL-118 and 11β-HSD1. Additionally, we showed that DNA methylation, hydroxymethylation, and histone phosphorylation were decreased by CMS induction, and increased by RL-118 treatment. In addition, CMS exposure caused the accumulation of reactive oxygen species (ROS)-induced damage and increased pro-oxidant enzymes—as well as pro-inflammatory mediators—through the NF-κB pathway and astrogliosis markers, such as GFAP. Of note, these modifications were reversed by 11β-HSD1 inhibition. Remarkably, although CMS altered mTORC1 signaling, autophagy was increased in the SAMP8 RL-118-treated mice. We also showed an increase in amyloidogenic processes and a decrease in synaptic plasticity and neuronal remodeling markers in mice under CMS, which were consequently modified by RL-118 treatment. In conclusion, 11β-HSD1 inhibition through RL-118 ameliorated the detrimental effects induced by CMS, including epigenetic and cognitive disturbances, indicating that GC-excess attenuation shows potential as a therapeutic strategy for age-related cognitive decline and AD.

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