Advertisement

Topics

PubMed Journal Database | Neurobiology of aging RSS

02:07 EDT 26th March 2019 | BioPortfolio

The US National Library of Medicine and National Institutes of Health manage PubMed.gov which comprises of more than 29 million records, papers, reports for biomedical literature, including MEDLINE, life science and medical journals, articles, reviews, reports and  books.

BioPortfolio aims to cross reference relevant information on published papers, clinical trials and news associated with selected topics - speciality.

For example view all recent relevant publications on Epigenetics and associated publications and clincial trials.

Showing PubMed Articles 1–25 of 502 from Neurobiology of aging

Delayed daily activity and reduced NREM slow-wave power in the APPswe/PS1dE9 mouse model of Alzheimer's disease.

Alzheimer's disease (AD) is associated with disrupted circadian rhythms and sleep, which are thought to reflect an impairment of internal circadian timekeeping that contribute to clinical symptoms and disease progression. To evaluate these hypotheses, a suitable preclinical model of AD is needed. We performed a comprehensive assessment of circadian rhythms and sleep in the APP/PS1 (APP/PS1) mouse model using long-term in vivo electroencephalogram (EEG) monitoring and behavioral assays from 5 to 22 months ...

Sleep EEG functional connectivity varies with age and sex, but not general intelligence.

Variations in the anatomical and functional connectivity between brain areas underlie both healthy and pathological variation in psychological measures. Largely independent from external stimuli, the sleep EEG is particularly well suited to measure individual variations in functional brain connectivity. In this study of 172 healthy individuals (17-69 years old), we show that functional connectivity between distant brain areas-reflected by the weighted phase lag index of the sleep EEG-is strongly affected b...

Age-related decrease in cortical excitability circadian variations during sleep loss and its links with cognition.

Cortical excitability depends on sleep-wake regulation, is central to cognition, and has been implicated in age-related cognitive decline. The dynamics of cortical excitability during prolonged wakefulness in aging are unknown, however. Here, we repeatedly probed cortical excitability of the frontal cortex using transcranial magnetic stimulation and electroencephalography in 13 young and 12 older healthy participants during sleep deprivation. Although overall cortical excitability did not differ between age...

Interaction of nutrition and genetics via DNMT3L-mediated DNA methylation determines cognitive decline.

Low homocysteine levels and B vitamin treatment are reported to protect against declining cognitive health. Both B vitamins and homocysteine are involved in the production of S-adenosylmethionine, a universal methyl donor essential for the process of DNA methylation. We investigated the effect of a damaging coding variant within the DNA methyltransferase gene DNMT3L (R278G, A/G) by examining B vitamin intake, homocysteine levels, cognitive performance, and brain atrophy in individuals in the VITACOG study o...

Cognitive heterogeneity among community-dwelling older adults with cerebral small vessel disease.

Some degree of ischemic injury to white matter tracts occurs naturally with age and is visible on magnetic resonance imaging as focal or confluent white matter hyperintensities. Its relationship to cognition, however, remains unclear. To explore this, community-dwelling adults between the ages 55 and 80 years completed structural imaging, neuropsychological testing, and questionnaires to provide objective measures and subjective experience of executive functioning. Volumetric lesion burden derived from str...

Oxytocin alters patterns of brain activity and amygdalar connectivity by age during dynamic facial emotion identification.

Aging is associated with increased difficulty in facial emotion identification, possibly due to age-related network change. The neuropeptide oxytocin (OT) facilitates emotion identification, but this is understudied in aging. To determine the effects of OT on dynamic facial emotion identification across adulthood, 46 young and 48 older participants self-administered intranasal OT or a placebo in a randomized, double-blind procedure. Older participants were slower and less accurate in identifying emotions. A...

Corticospinal control of normal and visually guided gait in healthy older and younger adults.

We investigated age-related differences in corticospinal control of muscle activity during normal and visually guided (VG) walking. Young (n = 15, 22.1 ± 1.7 years) and older (n = 15, 68.3 ± 2.7 years) participants performed normal walking and VG walking requiring precise foot placement based on visual cues. Coherence analysis was used to quantify coupling between electroencephalography and electromyography from the anterior tibial muscle (corticomuscular) and between the 2 ends of the anterior tibial...

Lentiviral vector-mediated overexpression of Klotho in the brain improves Alzheimer's disease-like pathology and cognitive deficits in mice.

Alzheimer's disease (AD) is the most common type of senile dementia. The antiaging gene Klotho is reported to decline in the brain of patients and animals with AD. However, the role of Klotho in the progression of AD remains elusive. The present study explored the effects and underlying mechanism of Klotho in a mouse model of AD. The upregulation of cerebral Klotho expression was mediated by an intracerebroventricular injection of a lentiviral vector that encoded Klotho (LV-KL) in 7-month-old amyloid precur...

Genetic analysis suggests high misassignment rates in clinical Alzheimer's cases and controls.

Genetic case-control association studies are often based on clinically ascertained cases and population or convenience controls. It is known that some of the controls will contain cases, as they are usually not screened for the disease of interest. However, even clinically assessed cases and controls can be misassigned. For Alzheimer's disease (AD), it is important to know the accuracy of the clinical assignment. The predictive accuracy of AD risk by polygenic risk score analysis has been reported in both c...

Functional network resilience to pathology in presymptomatic genetic frontotemporal dementia.

The presymptomatic phase of neurodegenerative diseases are characterized by structural brain changes without significant clinical features. We set out to investigate the contribution of functional network resilience to preserved cognition in presymptomatic genetic frontotemporal dementia. We studied 172 people from families carrying genetic abnormalities in C9orf72, MAPT, or PGRN. Networks were extracted from functional MRI data and assessed using graph theoretical analysis. We found that despite loss of bo...

Early and late effects of maternal experience on hippocampal neurogenesis, microglia, and the circulating cytokine milieu.

The maternal brain displays considerable plasticity, and motherhood is associated with changes in affective and cognitive function. Motherhood can alter the trajectory of brain aging, including modifications to neuroplasticity and cognition. Here, we investigated the short- and long-term effects of motherhood on hippocampal neurogenesis, microglial density and morphology, and circulating cytokines, domains known to be altered with age and implicated in cognition and mood. Female rats were bred then euthaniz...

Age-dependent changes in clock neuron structural plasticity and excitability are associated with a decrease in circadian output behavior and sleep.

Aging has significant effects on circadian behavior across a wide variety of species, but the underlying mechanisms are poorly understood. Previous work has demonstrated the age-dependent decline in behavioral output in the model organism Drosophila. We demonstrate that this age-dependent decline in circadian output is combined with changes in daily activity of Drosophila. Aging also has a large impact on sleep behavior, significantly increasing sleep duration while reducing latency. We used electrophysiolo...

Mutation profile of APP, PSEN1, and PSEN2 in Chinese familial Alzheimer's disease.

Causative mutations in the genes encoding amyloid precursor protein (APP), presenilin 1 (PSEN1), or presenilin 2 (PSEN2) account for a majority of cases of familial Alzheimer disease (FAD) inherited in an autosomal-dominant pattern. For the sake of characterizing mutations, index patients from 148 families with FAD were enrolled from mainland China. Sanger sequencing of the genes APP, PSEN1, and PSEN2 was performed to characterize the mutation spectrum of the Chinese population. Thirteen of 148 (8.8%) indiv...

Abnormalities of functional cortical source connectivity of resting-state electroencephalographic alpha rhythms are similar in patients with mild cognitive impairment due to Alzheimer's and Lewy body diseases.

Previous evidence has shown different resting-state eyes-closed electroencephalographic delta (

Fresh evidence for major brain gangliosides as a target for the treatment of Alzheimer's disease.

Although it was suggested that gangliosides play an important role in the binding of amyloid fragments to neuronal cells, the exact role of gangliosides in Alzheimer's disease (AD) pathology remains unclear. To understand the role of gangliosides in AD pathology in vivo, we crossed st3gal5-deficient (ST3) mice that lack major brain gangliosides GM1, GD1a, GD3, GT1b, and GQ1b with 5XFAD transgenic mice that overexpress 3 mutant human amyloid proteins AP695 and 2 presenilin PS1 genes. We found that ST3 5XFAD...

Downregulation of SNX27 expression does not exacerbate amyloidogenesis in the APP/PS1 Alzheimer's disease mouse model.

There is in vitro evidence that sorting nexin family member 27 (SNX27), a member of the retromer complex, changes the distribution of the amyloid-beta (Aβ) precursor protein (APP) to promote its recycling and thereby prevent the production of Aβ, the toxic protein associated with Alzheimer's disease (AD). In this study, we analyzed the phenotype of the familial AD APP/PS mouse strain lacking one copy of the SNX27 gene. The reduction in SNX27 expression had no significant effect on the in vivo accumulati...

The influence of tau, amyloid, alpha-synuclein, TDP-43, and vascular pathology in clinically normal elderly individuals.

Many individuals live to older ages without clinical impairment. It is unknown whether brain pathologies in these individuals are associated with subtle clinical deficits. We analyzed the brains of 161 clinically normal (Clinical Dementia Rating score = 0) older individuals enrolled in the Mayo Clinic Patient Registry or Study of Aging. We assessed for the presence and burden of beta-amyloid, tau, alpha-synuclein, TDP-43, and vascular pathology. We investigated whether pathologies were associated with ante...

Acute treatment with the PDE4 inhibitor roflumilast improves verbal word memory in healthy old individuals: a double-blind placebo-controlled study.

There is ample evidence that phosphodiesterase 4 (PDE4) inhibition can improve memory performance in animal studies. In the present study, we examined the acute effects of the PDE4 inhibitor roflumilast on memory performance in healthy individuals (60-80 years of age). We tested the effects of acute roflumilast administration (100, 250, 1000 μg) in a double-blind, placebo-controlled, 4-way crossover design. Participants were first screened for their verbal word memory performance to ensure normal memory ...

Age-related differences in neural spectral power during motor learning.

We investigated how older adults preserve the capability to acquire new motor skills in the face of age-related brain alterations. We assessed neural changes associated with learning a bimanual coordination task over 4 days of practice in healthy young (n = 24) and older adults (n = 24). The electroencephalogram was recorded during task performance at the start and end of training. Motor performance improved with practice in both groups, but the amount of learning was lower in the older adults. Beta power...

Cognitive aging is not created equally: differentiating unique cognitive phenotypes in "normal" adults.

Age-related cognitive decline is a public health problem but highly diverse and difficult to predict. We captured nonoverlapping cognitive phenotypes in high-functioning adults and identified baseline factors differentiating trajectories. Three hundred fourteen functionally normal adults (M = 69 y) completed 2+ visits. Participants with sample-based longitudinal slopes in memory or processing speed less than -1 SD were classified as "declining" on that measure; 29 and 50 individuals had slopes less than ...

Event-related potentials associated with auditory attention capture in younger and older adults.

A deviant-related negativity (DRN), mismatch negativity (MMN), and P3a are electrophysiological measures thought to reflect processes involved in the involuntary switching of attention to a task-irrelevant stimulus. The purpose of this article was to determine whether healthy older adults involuntarily detect unattended auditory stimuli as efficiently as younger adults. To test this, 20 younger adults (aged 18-30 years) and 20 older adults (aged 65+ years) were presented with to-be-ignored auditory sequence...

Prestimulus and poststimulus oscillatory activity predicts successful episodic encoding for both young and older adults.

Healthy aging is associated with declines in episodic memory performance that are due in part to deficits in encoding. Emerging results from young adult studies suggest that the neural activity during the time preceding stimulus presentation is sensitive to episodic memory performance. It is unknown whether age-related declines in episodic memory are due solely to changes in the recruitment of processes elicited by stimuli during encoding or also in processes recruited in anticipation of these stimuli. Here...

Unaltered prion disease in mice lacking developmental endothelial locus-1.

Progression of prion diseases is driven by the accumulation of prions in the brain. Ablation of microglia or deletion of the eat-me-signal, milk-fat globule epidermal growth factor VIII (Mfge8), accelerates prion pathogenesis, suggesting that microglia defend the brain by phagocytosing prions. Similar to Mfge8, developmental endothelial locus-1 (Del-1) is a secreted protein that acts as an opsonin bridging phagocytes and apoptotic cells to facilitate phagocytosis. We therefore asked whether Del-1 might play...

Multimodal MRI evaluation of parkinsonian limbic pathologies.

Previous multimodal magnetic resonance imaging (MRI) studies of parkinsonian syndromes have focused primarily on motor-related basal ganglia structures. The present study investigated MRI changes in nonmotor-related limbic structures in 35 Parkinson's disease, 16 multiple system atrophy parkinsonian subtype, 17 progressive supranuclear palsy, and 37 control subjects. Mean diffusivity (MD), fractional anisotropy, transverse relaxation rate (R2*), quantitative susceptibility mapping, and volume measurements w...

Cholecystokinin and Alzheimer's disease: a biomarker of metabolic function, neural integrity, and cognitive performance.

Cholecystokinin (CCK) is a satiety hormone that is highly expressed in brain regions like the hippocampus. CCK is integral for maintaining or enhancing memory and thus may be a useful marker of cognitive and neural integrity in participants with normal cognition, mild cognitive impairment, and Alzheimer's disease (AD). Cerebrospinal fluid (CSF) CCK levels were examined in 287 subjects from the Alzheimer's Disease Neuroimaging Initiative. Linear or voxelwise regression was used to examine associations betwee...


Advertisement
Quick Search
Advertisement
Advertisement