Search results for "geriatrics."
showing 10 items of 1386 documents
A New Frailty Score for Experimental Animals Based on the Clinical Phenotype: Inactivity as a Model of Frailty.
2016
The development of animal models to study human frailty is important to test interventions to be translated to the clinical practice. The aim of this work was to develop a score for frailty in experimental animals based in the human frailty phenotype. We also tested the effect of physical inactivity in the development of frailty as determined by our score. Male C57Bl/6J mice, individually caged, were randomly assigned to one of two groups: sedentary (inactive) or spontaneous wheel-runners. We compared the sedentary versus the active lifestyle in terms of frailty by evaluating the clinical criteria used in humans: unintentional weight loss; poor endurance (running time); slowness (running sp…
Deciphering Alzheimer’s Disease Pathogenic Pathway: Role of Chronic Brain Hypoperfusion on p-Tau and mTOR
2021
This review examines new biomolecular findings that lend support to the hemodynamic role played by chronic brain hypoperfusion (CBH) in driving a pathway to Alzheimer’s disease (AD). CBH is a common clinical feature of AD and the current topic of intense investigation in AD models. CBH is also the basis for the vascular hypothesis of AD which we originally proposed in 1993. New biomolecular findings reveal the interplay of CBH in increasing tau phosphorylation (p-Tau) in the hippocampus and cortex of AD mice, damaging fast axonal transport, increasing signaling of mammalian target of rapamycin (mTOR), impairing learning-memory function, and promoting the formation of neurofibrillary tangles…
Telomere Length and Frailty: The Helsinki Birth Cohort Study
2018
Objectives: Telomere length is associated with aging-related pathologies. Although the association between telomere length and frailty has been studied previously, only a few studies assessing longitudinal changes in telomere length and frailty exist. Design: Longitudinal cohort study. Setting and participants: A subpopulation of the Helsinki Birth Cohort Study consisting of 1078 older adults aged 67 to 79 years born in Helsinki, Finland, between 1934 and 1944. Measures: Relative leukocyte telomere length (LTL) was measured using quantitative real-time polymerase chain reaction at the average ages of 61 and 71 years, and at the latter the participants were assessed for frailty according to …
A Stress-Resistant Lipidomic Signature Confers Extreme Longevity to Humans.
2015
Plasma lipidomic profile is species specific and an optimized feature associated with animal longevity. In the present work, the use of mass spectrometry technologies allowed us to determine the plasma lipidomic profile and the fatty acid pattern of healthy humans with exceptional longevity. Here, we show that it is possible to define a lipidomic signature only using 20 lipid species to discriminate adult, aged and centenarian subjects obtaining an almost perfect accuracy (90%-100%). Furthermore, we propose specific lipid species belonging to ceramides, widely involved in cell-stress response, as biomarkers of extreme human longevity. In addition, we also show that extreme longevity present…
Resting-state posterior alpha rhythms are abnormal in subjective memory complaint seniors with preclinical Alzheimer's neuropathology and high educat…
2020
International audience; Cognitive reserve is present in Alzheimer's disease (AD) seniors with high education attainment making them clinically resilient to extended brain neuropathology and neurodegeneration. Here, we tested whether subjective memory complaint (SMC) seniors with AD neuropathology and high education attainment of the prospective INSIGHT-preAD cohort (Paris) may present abnormal eyesclosed resting state posterior electroencephalographic rhythms around individual alpha frequency peak, typically altered in AD patients. The SMC participants negative to amyloid PET AD markers (SMCneg) with high (over low-moderate) education level showed higher posterior alpha 2 power density (pos…
Relationship Between Body Mass Index, ApoE4 Status, and PET-Based Amyloid and Neurodegeneration Markers in Amyloid-Positive Subjects with Normal Cogn…
2018
Body weight loss in late-life is known to occur at a very early stage of Alzheimer's disease (AD). Apolipoprotein E4 (ApoE4) represents a major genetic risk factor for AD and is linked to an increased cortical amyloid-β (Aβ) accumulation. Since the relationship between body weight, ApoE4, and AD pathology is poorly investigated, we aimed to evaluate whether ApoE4 allelic status modifies the association of body mass index (BMI) with markers of AD pathology. A total of 368 Aβ-positive cognitively healthy or mild cognitive impaired subjects had undergone [18F]-AV45-PET, [18F]-FDG-PET, and T1w-MRI examinations. Composite cortical [18F]-AV45 uptake and [18F]-FDG uptake in posterior cingulate cor…
Multicomponent Training Prevents Memory Deficit Related to Amyloid-β Protein-Induced Neurotoxicity.
2021
Background: Alzheimer’s disease (AD) is characterized by the accumulation of the amyloid-β peptide in the brain, leading to early oxidative stress and neurotoxicity. It has been suggested that physical exercise could be beneficial in preventing AD, but studies with multicomponent training are scanty. Objective: Verify the effects of multicomponent exercise training to prevent deficits in recognition memory related to Aβ neurotoxicity. Methods: We subjected Wistar rats to multicomponent training (including aerobic and anaerobic physical exercise and cognitive exercise) and then infused amyloid-β peptide into their hippocampus. Results: We show that long-term multicomponent training prevents …
Short-Term Effects of Microglia-Specific Mitochondrial Dysfunction on Amyloidosis in Transgenic Models of Alzheimer's Disease.
2018
Reduction of mitochondrial activity is a subtle and early event in the pathogenesis of Alzheimer’s disease. Mitochondrial damage and consequentially enhanced production of reactive oxygen species is particularly occurring in the vicinity of amyloid plaques. Since all cells are affected by mitochondrial damage, analyses of cell type-specific effects are challenging. To study the impact of mitochondrial alterations on microglial activity in a homogeneous genetic background, we generated bone marrow chimeras of irradiated 46-days-old APP-transgenic mice. For reconstitution, bone marrow from CX3CR1-eGFP mice with mitochondria of either non-obese diabetic or C57BL/6J animals was utilized. Succes…
Altered Gut Microbiome Composition and Tryptic Activity of the 5xFAD Alzheimer's Mouse Model.
2017
The regulation of physiological gut functions such as peristalsis or secretion of digestive enzymes by the central nervous system via the Nervus vagus is well known. Recent investigations highlight that pathological conditions of neurological or psychiatric disorders might directly interfere with the autonomous neuronal network of the gut - the enteric nervous system, or even derive from there. By using a murine Alzheimer's disease model, we investigated a potential influence of disease-associated changes on gastrointestinal properties. 5xFAD mice at three different ages were compared to wild type littermates in regard to metabolic parameters and enzymes of the gut by fluorimetric enzyme as…
Endocrinology of Aging From a Muscle Function Point of View: Results From the Toledo Study for Healthy Aging.
2016
Aging is a process that involves a reduction in muscle strength and anabolic hormone concentrations, which impacts significantly on health.To study the hormone/total strength (H/TS) ratio as a proxy of anabolic insensitivity status in elders, and its relationship with disability, hospitalization, and mortality risk.A total of 1462 persons aged ≥65 years from the Toledo Study of Healthy Aging participated in this study. Serum concentrations of insulin like growth factor 1, total and free testosterone, dehydroepiandrosterone, dehydroepiandrosterone sulfate, and 17β-estradiol were measured. Total maximal voluntary isometric strength was obtained (handgrip, shoulder, hip, and knee) using standa…