It is known since a long time that the hippocampus is sensitive to aging. Thus, there is a reduction in the hippocampal volume during aging. This age-related volume reduction is paralleled by behavioral and functional deficits in hippocampus-dependent learning and memory tasks. This age-related volume reduction of the hippocampus is ...

Energy homeostasis and fuel metabolism undergo significant modifications in the course of aging. This presents in elderly subjects either as increased body mass and glucose intolerance - which may lead to obesity and type 2 diabetes - or loss of appetite, which may also seriously compromise health. The hypothalamic expression ...

Detergent-resistant membranes (DRMs) are a class of specialized microdomains that compartmentalize several signal transduction processes. In this work, DRMs were isolated from cerebral cortex synaptic endings (Syn) on the basis of their relative insolubility in cold Triton X-100 (1%). The lipid composition and marker protein content were analyzed in DRMs ...

Microglia have neuroprotective capacities, yet chronic activation can promote neurotoxic inflammation. Neuronal fractalkine (FKN), acting on CX(3)CR1, has been shown to suppress excessive microglia activation. We found that disruption in FKN/CX(3)CR1 signaling in young adult rodents decreased survival and proliferation of neural progenitor cells through IL-1β. Aged rats were found ...

We evaluated effects of age on components of excitation-contraction (EC) coupling in ventricular myocytes from male and female rats to examine sex differences in mechanisms responsible for age-related contractile dysfunction. Myocytes were isolated from anesthetized young adult (approximately 3 mo) and aged (approximately 24 mo) Fischer 344 rats. Ca(2+) concentrations ...

BACKGROUND: Deformability of erythrocytes plays a key role in the impairment of the microcirculation in hypertension. However, erythrocyte deformability in spontaneously hypertensive rats (SHR) during development of hypertension has not been fully investigated so far. METHODS AND RESULTS: Erythrocyte filterability (whole cell deformability) was investigated in relation to blood pressure ...

Further clarification is needed to address the paradox that memory formation, aging and neurodegeneration all involve calcium influx, oxyradical production (ROS) and activation of certain signaling pathways. In aged rats and in APP/PS-1 mice, cognitive and hippocampal Ca(2+) dysregulation was reversed by food supplementation with a high antioxidant blueberry extract. ...

During the aging process of mammals first a phase of obesity and increased adiposity is observed in middle-aged subjects, then anorexia and loss of body weight (sarcopenia) at old age. A possible age-dependence of the anorexigenic alpha-melanocyte-stimulating-hormone (alpha-MSH) in these regulatory changes was studied. Male Wistar rats aged 6-8 weeks ...

Expression profiles of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR), apolipoprotein E (ApoE) and cholesterol 24S-hydroxylase (CYP46), proteins involved in cholesterol biosynthesis, transport and excretion from the CNS, were analyzed in the rat cortex, hippocampus and cerebellum as a function of aging (6–24 months) and in response to long-term dietary restriction (DR). ...

Ketogenic diets (KDs) have shown beneficial effects in experimental models of neurodegeneration, designating aged individuals as possible recipients. However, few studies have investigated their consequences on aging brain. Here, late-adult rats (19 months of age) were fed for 8 weeks with two medium chain triglycerides-supplemented diets (MCT-SDs) and the average ...

Genistein is an estrogenic soy isoflavone widely promoted for healthy aging, but its effects on cognitive function are not well-understood. We examined the cognitive effects of once daily oral genistein treatment at two doses (approximately 162 microg/kg/day low dose and a 323 microg/kg/day high dose) in ovariectomized young (7 month), ...

Ghrelin circulates as acylated (AG) and unacylated (or desacyl) ghrelin (UAG). We aimed at clarifying the effect of age and sex on plasma deacylation and degradation of AG in vivo and in vitro in the rat. In vivo, we compared AG and UAG concentrations following administration of 1 microg AG ...

Although Rhamnaceae are distributed worldwide today, the former hypothesis for its Laurasian origins may need to be reconsidered in view of recently discovered fossils from the Guaduas Formation of central Colombia (∼68 Ma), including fossil leaves (Berhamniphyllum) and a fruit (Archaeopaliurus boyacensis). Recent phylogenetic studies calibrate the stem of Rhamnaceae ...

Research in aging laboratory animals has characterized physiological and cellular alterations in medial temporal lobe structures, particularly the hippocampus, that are central to age-related memory deficits. The current study compares molecular alterations across hippocampal subregions in a rat model that closely mirrors individual differences in neurocognitive features of aging humans, ...

Dysregulation of intracellular calcium homeostasis has been linked to neuropathological symptoms observed in aging and age-related disease. Alterations in the distribution and relative frequency of calcium-binding proteins (CaBPs), which are important in regulating intracellular calcium levels, may contribute to disruption of calcium homeostasis. Here we examined the laminar distribution of ...

Hypoxia transiently increases transcription of the gene encoding heme oxygenase-1 (HO-1) and potently activates production of endothelin-1 (ET-1), the latter of which plays a central role in cellular adaptation to hypoxia. The ventilatory response to hypoxia attenuates with aging, and decreased responsiveness to hypoxia is seen in the aged vs. ...

Aged people and rats have a reduced ability to maximally concentrate their urine. Many of the key transport proteins that contribute to urine concentrating ability are reduced in the medulla of aged rats. The reductions in the abundances of water, sodium, and urea transport proteins, and their reduced response to ...

Cortical spreading depression (CSD) is a feature of stroke pathophysiology. As stroke incidence increases with age, we have examined the effects of early aging and chronic cerebral hypoperfusion on CSD in rats. Three groups were studied: Young, 2-month-old animals; Middle-aged-2VO, subjected to 8 months of bilateral carotid occlusion from 2-month-of-age; ...

The possible influence of advanced age on intestinal drug absorption was investigated by determining the effects of aging on (i) solubility of model drugs in human intestinal fluids (HIF) obtained from two age groups (18-25 years; 62-72 years); and (ii) transepithelial permeation of model drugs across intestinal tissue excised from ...

Brain aging is related to the numerous structural and functional changes including decreased synaptic plasticity. The beneficial effects of dietary restriction (DR) are well known but insufficiently investigated at the level of plasticity-related markers. Therefore, the aim of this study was to examine the expression profiles of proteins structurally and ...

Orexin/hypocretin is indicated to affect various physiological functions and behaviors, such as energy balance, feeding, wake-sleep cycle, stress response, and reproduction. This study investigated postnatal development and aging changes of the orexin neuron in the male rat hypothalamus. The brain tissue of rats from 1 week to 24 months old ...

The GnRH decapeptide controls reproductive function through its release from neuroendocrine terminals in the median eminence, a site where there is a convergence of numerous nerve terminals and glial cells. Previous work showed dynamic changes in the GnRH-glial-capillary network in the median eminence under different physiological conditions. Because aging in ...

Ketogenic diets (KDs) have been applied in the therapy of paediatric epilepsy for nearly a century. Recently, beneficial results have also been reported on metabolic disorders and neurodegeneration, designating aged individuals as possible recipients. However, KDs efficacy decrease after the suckling period, and very little is known about their impact ...

The risk for cardiovascular disease (CVD) increases with advancing age; however, the age at which CVD risk increases significantly is delayed by more than a decade in women compared with men. This cardioprotection, which women experience until menopause, is presumably due to the presence of ovarian hormones, in particular, estrogen. ...

To gain insight into the contribution of d-serine to impaired cognitive aging, we compared the metabolic pathway and content of the amino acid as well as d-serine-dependent synaptic transmission and plasticity in the hippocampus of young and old rats of the Wistar and Lou/C/Jall strains. Wistar rats display cognitive impairments ...

We investigated age-associated changes in the expression and deposition of collagen and hyaluronan (hyaluronic acid; HA) in aged vocal folds. Thirty Sprague-Dawley rats were involved in this study. For gene expression analyses, 15 animals were divided into 3 age groups of young (2 month), adult (9 month), and elderly (18 ...

In the present study, the cortex volume, total volume, total length and mean diameter of the myelinated fibers in the cortices of young, middle-aged, and aged Long-Evans rats were quantitatively investigated by using stereological methods and electron microscopy techniques. There were no significant differences in the myelinated fibers between young ...

Despite antiproliferative effects of melatonin on cultured tumor cells, its effects on normal cells are less clear. The action of melatonin on telomerase activity in ageing of gastric mucosal tissues also is not known. In this study, we investigated the age-related changes in telomerase activity and cellular proliferation rate of ...

AIM OF THE STUDY: Aging is thought to affect emotions including anxiety, and a herbal medicine, yokukansan (YKS), is used to treat emotional disturbances associated with age-related neurodegenerative disorders such as Alzheimer's disease, but its pharmacological properties have not been fully understood. The present study was designed to examine whether ...

Erectile dysfunction (ED) is a major public health problem that seriously affects the quality of life of patients and their partners and its prevalence increases significantly with ageing. In this study, we tested the hypothesis that age-associated decrease in penile endothelial (eNOS) and neuronal nitric oxide synthase (nNOS) activity in ...

After brain injury, astrocytes acquire a reactive phenotype characterized by a series of morphological and molecular modifications, including the expression of the cytoskeletal protein vimentin. Previous studies have shown that estradiol down-regulates reactive astrogliosis. In this study we assessed whether raloxifene and tamoxifen, two selective estrogen receptor modulators, have effects ...

The decline in physiological functions with aging may affect the ability of the SCN, the biological clock, circadian pacemaker to transmit rhythmic information to other neural target sites, and thereby modify the expression of biological rhythms resulting in circadian disorders. Neurotransmitter serotonin plays important role in the photic and non-photic ...

Presbycusis can be considered a slow age-related peripheral and central deterioration of auditory function which manifests itself as deficits in speech comprehension, especially in noisy environments. The present study examined neural correlates of a simple broadband noise stimulus in primary auditory cortex (A1) of young and aged Fischer-Brown Norway (FBN) ...

Although the flowering of facultative biennials is size-dependent, flowering size varies markedly within a single population as well as among populations. In this study, 15 half-sib families of the facultative biennial Aster kantoensis were grown from seeds at three nutrient levels (low, medium, and high). A significant nutrient × family ...

Aging leads to reduced cellular immunity with consequent increased rates of infectious disease, cancer, and autoimmunity in the elderly. The sympathetic nervous system (SNS) modulates innate and adaptive immunity via innervation of lymphoid organs. In aged Fischer 344 (F344) rats, noradrenergic (NA) nerve density in secondary lymphoid organs declines, which ...

Dysfunctions of the ubiquitin proteasome system (UPS) have been proposed to be involved in the aetiology and/or progression of several age-related neurodegenerative disorders. However, the mechanisms linking proteasome dysfunction to cell degeneration are poorly understood. We examined in young and aged rat hippocampus the activation of the unfolded protein response ...

Melatonin exerts many physiological functions via its G protein-coupled receptors. In the present study, we investigated age-related changes in MT2 melatonin receptor immunoreactivity and its levels in the gerbil hippocampus during normal aging. In the postnatal month 1 (PM 1) group, MT2 immunoreaction was well observed in neurons in all ...

Aging may be an important factor affecting brain injury by intracerebral hemorrhage (ICH). In the present study, we investigated the responses of glial cells and monocytes to intracerebral hemorrhage in normal and aged rats. ICH was induced by microinjecting autologous whole blood (15 microL) into the striatum of young (4 ...

There is evidence of structural and functional deterioration in the brain, including the prefrontal cortex (PFC) and hippocampus, during the normal aging process in animals and humans. Extracellular matrix-associated glycoproteins, such as chondroitin sulfate proteoglycans (CSPGs), are involved in not only maintaining the structures and functions of adult neurons, but ...

During ageing, the function of sinoatrial node (SAN), the pacemaker of the heart, declines, and the incidence of sick sinus syndrome increases markedly. The aim of the study was to investigate structural and functional remodelling of the SAN during ageing. Rats, 3 and 24 months old (equivalent to young adult ...

Cyclooxygenase (COX)-derived vasoconstrictory prostanoids contribute to impaired endothelium-dependent vasorelaxation in aging male (m) spontaneously hypertensive rats (SHR); however, vasomotor responses in aging female (f) SHR and sex differences in aging SHR are unknown. Examining mechanisms governing dysfunction in aging fSHR will contribute to understanding sex-dependent vascular complications in advanced hypertension. ...

Diseases of aging produce many alterations in the retina, but changes in growth factor signaling in normal aging are less characterized. This study investigated modifications in insulin-like growth factor-1 (IGF-1) receptor (IGF-1R) signaling in the retina of Brown Norway x Fischer 344 F1 hybrid rats at 8, 22, and 32 ...

PURPOSE: Kindling of audiogenic seizure (AGS) involves >or=14 AGS over 1-2 weeks in genetically epilepsy-prone rats (GEPR-9s) and induces gradual seizure duration increases, epileptiform electroencephalography (EEG), and emergence of post tonic clonus (PTC), which are long-lasting. N-methyl-d-aspartate (NMDA)-receptor activation in lateral amygdala (LA) is implicated in AGS kindling initiation. However, ...

Recent progress in understanding visceral afferents, some of it reviewed in the present issue, serves to underscore how little is known about the aging of the visceral afferents in the gastrointestinal (GI) tract. In spite of the clinical importance of the issue-with age, GI function often becomes severely compromised-only a ...

Dystrophic axons and terminals are common in the myenteric plexus and smooth muscle of the gastrointestinal (GI) tract of aged rats. In young adult rats, alpha-synuclein in its normal state is abundant throughout the myenteric plexus, making this protein-which is prone to fibrillization-a candidate marker for axonopathies in the aged ...

Calretinin (CR)-immunoreactive interneurons are well known as the interneuron specific interneurons in the hippocampus. CR-immunoreactive neurons form cellular network and regulate the activity of other GABAergic inhibitory interneurons in the hippocampus. In the present study, we investigated age-related changes in CR-immunoreactive neurons and protein levels in the gerbil hippocampus during ...

The current study examined effects of chronic estradiol replacement on a prefrontally-mediated working memory task at different ages in a rodent model. Ovariectomized young, middle-aged, and old Long-Evans rats were given 5% or 10% 17beta-estradiol in cholesterol vehicle via Silastic implants and tested on an operant delayed spatial alternation task ...

Cyclooxygenases-2 (COX-2) is not only related to inflammation but also plays critical roles in brain development and synaptic signaling. In the present study, we investigated age-related changes in COX-2 immunoreactivity and protein levels in the gerbil hippocampus. In the hippocampal CA1 region (CA1) and dentate gyrus (DG), weak COX-2 immunoreactivity ...

BACKGROUND: Although age-related impairment of endothelial progenitor cells (EPCs) has been documented in recent studies, the detailed role of aging-induced environment in EPCs remains unclear. METHODS: Two and 20 months old Sprague-Dawley female rats were used in the present study. EPCs isolated from young (YEPCs) and aged (AEPCs) rats were ...

OBJECTIVES/HYPOTHESIS: To investigate the effects of an augmented acoustic environment (AAE) on age-related hearing loss (ARHL) and outer hair cell (OHC) pathology in middle-aged Fischer 344/NHsd (F344/NHsd) rats. METHODS: Eleven F344/NHsd rats were divided into two groups: 1) the AAE group (n = 5), which was exposed to 4-20 kHz ...