Experimental Aging Research最新文献

Objectives: Living a long life does not guarantee the maintenance of optimal cognitive functioning; however, similar to older adults in general, cognitive reserve may also protect oldest-old adults from cognitive decline. The purpose of this study was to assess cognitive reserve among centenarians and octogenarians and to evaluate a process model of cognitive reserve.

Methods: A total of 321 centenarians and octogenarians from the Georgia Centenarian Study were included in this study. Cognitive reserve components included level of education, occupational responsibility, current social engagement, past engaged lifestyle, and activity. Cognitive functioning was measured with the Mini-Mental Status Examination.

Results: Structural equation modeling was computed, and the overall model fit well, χ2 (df = 3) = 5.02, p = .17; CFI = .99, RMSEA = .05. Education is directly and indirectly related to cognitive functioning through occupational responsibility and past engaged lifestyle. Current social engagement is related to cognitive functioning directly and indirectly through current activities. The four direct predictors (i.e., education, current social engagement, current activity, and past engaged lifestyle) explained 35% of the variance in cognitive functioning.

Conclusion: The results provide important information for cognitive reserve theories with implications for interventions that build cognitive reserve.

Objectives: This study examined the effects of one-month naringin administration and exercise training on cognitive impairment and H₂S signaling pathway in an Amyloid β (Aβ)-injected rat.

Methods: Rats were divided into four groups: control group; rats underwent Aβ microinjection surgery, exercise group; rats underwent Aβ microinjection surgery and trained by treadmill for four weeks, naringin group; rats underwent Aβ microinjection surgery, and rats orally administrated 80 mg.kg^-1 naringin for four weeks, naringin+exercise group; rats underwent Aβ microinjection surgery and were trained by treadmill for four weeks, and also, rats orally administrated 80 mg.kg^-1 naringin for four weeks. After one month of treatment, spatial learning and memory were measured, and then hippocampi were sampled. S-adenosylmethionine (SAM), cystathionine-β-synthase (CBS), hydrogen sulfide (H₂S) levels, and neuronal death were detected in the hippocampi of rats.

Results: Naringin and exercise improved spatial learning (latency time, P < .001) and memory (P < .001) in the Morris Water Maze test in Aβ-injected rats compared with the control group. SAM (P < .01), CBS (P < .001), and H₂S (P < .01) levels are increased in the naringin+exercise group compared with the control group.

Conclusion: The result of this study supports the effect of exercise and/or naringin to improve cognitive dysfunction and cell death through the production of H₂S.

Background: Physical inactivity significantly increases risk of cardiovascular diseases, which are highly prevalent in aging. Conversely, higher levels of physical activity in aging have been associated with benefits for physical and cognitive health and is hypothesized to prevent and reduce development of cardiovascular risk factors. However, those older adults with the highest activity levels (i.e., Master Athletes [MA]) are relatively understudied, and even fewer studies involve female MA.

Objective: The aim of this study was to compare the physiological, physical, and cognitive profiles of an 83-year-old track-and-field MA runner to a sample of inactive age-matched females.

Results: Results revealed the MA had a high peak oxygen uptake and had superior performance on visuospatial memory tasks compared to her inactive counterparts. Cerebral blood flow was slightly elevated in the MA, but lower cerebrovascular reactivity was revealed compared to the other female included in the magnetic resonance imaging portion.

Conclusion: Our results suggest that high levels of physical activity have benefits on multiple aspects of an aging female's life and that more studies should include MA, as well as a spectrum of cardiorespiratory fitness to further understand the role of physical activity in female aging.

Introduction: Carers of Alzheimer's suffer from caregiver overload, anxiety and depression. Changes in caregiving brought about by pandemic restrictions (COVID-19) may play a role. The aim was to explore the caregiver profile and assess the influence of the pandemic on informal and formal caregivers in a Spanish sample.

Method: Sixty caregivers participated. An ad hoc questionnaire, ZBI, STAI and BDI were administered.

Results: Informal caregivers were more overloaded, anxious and depressed than professional caregivers. Both groups perceived themselves to be more sad, worried and stressed than in the pre-pandemic situation. The pandemic-generated variables associated with caregiving did not influence caregiver overload in both groups. In informal caregivers, worsening of the patient with stress and changes in perceived social support with anxiety and depression. In professional caregivers, changes in routine were associated with stress and lower depression and changes in perceived social support with higher caregiver strain. Changes in caregiving routine and changes in perceived social support were predictors of overload and emotional distress in both caregivers.

Conclusions: Overload was not influenced by the pandemic situation. Changes in caregiving routine and lack of social support were found to be predictors of overload and emotional distress in both types of caregivers.

Objectives: Using Terror Management Theory and Social Identity Theory as frameworks, we examined whether the relationship of aging anxiety to compassion for and emotional distance from older adults was mediated by ageist attitudes and whether an older adult's health condition moderated these relationships.

Method: Using an experimental design, 292 middle-aged adults (40-55 years) were assigned to read a description of an older adult with Alzheimer's Disease (AD), prostate cancer, or who was healthy.

Results: The relationship of aging anxiety to compassion was mediated by ageist attitudes in both the AD and prostate cancer conditions. More ageist attitudes related to less compassion more strongly for unhealthy older adult conditions than for the healthy older adult condition as well as for the AD condition compared to the cancer condition. Ageist attitudes related to more emotional distance from the older adult with AD than the older adult with cancer.

Discussion: Older adults with AD may evoke a stronger relationship of ageist attitudes with emotions toward older adults. These findings extend previous research by examining middle-aged participants, a population often serving as caregivers to their aging relatives.

Background: Chronic kidney disease (CKD) is associated with an increased risk of frailty, morbidity, and mortality in older adults. Limited health literacy (HL) is a condition that can cause frailty in CKD. Frailty leads to a decreased resistance to stress situations caused by activities of daily living and increased morbidity and mortality. The aim of this study was to investigate the relationship between HL and frailty in older adults with stage 4-5 CKD.

Methods: A total of 109 patients with stage 4-5CKD were included. All patients underwent a comprehensive geriatric assessment. Health literacy was assessed by the Turkish version of the European Health Literacy Questionnaire. Frailty status was measured using the Fried Frailty Index.

Results: The median age was 72 (68-80) years and 72 patients (66.1%) had lowHL. Forty-six patients (42.2%) were frail, and frailty was more common in the low HL group.

Conclusion: The present study demonstrated that low HL level was common in geriatric patients with stage 4-5 CKD and was associated with frailty, as well as a decrease in daily and instrumental life activities, decrease in acceptance of illness scale, and compliance with medical treatment.

Objectives: Dynamic processes unfolding over later adulthood are of prime interest to gerontological researchers. Time-varying effect modeling (TVEM) accommodates dynamic change trajectories, but its use in gerontological research is limited. We introduce and demonstrate TVEM with an empirical example based on the National Health and Aging Trends Study (NHATS).

Methods: We examined (a) age-varying prevalence of past month elevated symptoms of depression and anxiety and (b) age-varying associations between older adults' elevated symptoms of depression and anxiety and needing help with basic activities of daily living and educational attainment.

Results: The proportion of participants reporting elevated symptoms of depression and anxiety in the past month increased gradually from 23-29% across the ages 70-92. Individuals needing help with ADLs had higher odds of reporting elevated symptoms of depression and anxiety, however the association was strongest for those in their 60s versus 80s. Across all ages, adults with lower education levels had higher odds of reporting elevated symptoms of depression and anxiety, an association that also varied by age.

Conclusion: We demonstrated TVEM's value for studying dynamic associations that vary across chronological age. With the recent availability of free, user-friendly software for implementing TVEM, gerontological researchers have a new tool for exploring complex change processes that characterize older adults' development.

Background: Understanding the strategies people with amnestic mild cognitive impairment (aMCI) spontaneously use can inform targeted memory training.

Method: Strategy use was observed for 99 people with aMCI and 100 healthy older adults (HOA) on two memory tasks.

Results: No differences were found between aMCI and HOA in the amount or types of strategies used, but strategy use varied with task. Association was more effective for one task, whereas on the other task, use of written notes or multiple strategies were detrimental to performance and related to poorer performance than active (spaced) retrieval, for aMCI.

Conclusion: Our findings suggest the importance of identifying ineffective habits, in addition to instruction in more beneficial approaches.

Background: It has been reported that LXR agonist can inhibit Aβ generation and alleviate Aβ-induced various adverse reactions in vivo and in vitro experiments, but the mechanisms have not been clarified. The study aimed to observe the effect of LXR agonist TO901317 on the cognitive function of AD transgenic mice fed with cholesterol-rich diet (CRD), and to explore the possible mechanism. Methods: 32 male 6-month-old double transgenic AD mice were enrolled and randomly divided into 4 groups: control (normal diet) group, CRD treatment group, TO901317 treatment group and GSK2033 treatment group. After 3 month, Morris water maze was for the changes of spatial exploration and memory ability; ELISA was for detecting the production of Aβ42 in the brain; the concentration of total cholesterol (TC), low density lipoprotein (LDL) and high density lipoprotein (HDL) in serum were detected by cholesterol enzyme colorimetry; Finally, the expression of LXR-β, RXR-α, ABCA1, caveolin-1, BACE1 and APP at protein level in the brains was measured by Western blotting.

Results: Compared with the control group, the learning, memory ability and spatial exploration ability of the mice were more significantly serious in the CRD group (P<0.05); The contents of TC and LDL in the serum and the production of Aβ42 in the brains were significantly increased (P<0.05), but HDL was remarkably decreased (P<0.05); The protein levels of LXR-β, RXR-α and ABCA1 were also significantly decreased (P<0.05); The expression of caveolin-1, APP and BACE1 were evidently increased (P<0.05). However, after treatment with TO901317, the impaired learning and memory and spatial exploration ability of the mice were significantly improved (P<0.05); The contents of TC and LDL in serum and the production of Aβ42 in the brains were significantly decreased (P<0.05), but HLD was increased (P<0.05); The protein levels of LXR-β, RXR-α, ABCA1were all significantly increased (P<0.05), while, the expression of caveolin-1, APP and BACE1 were all significantly decreased (P<0.05). All the changes were reversed by GSK2033 (P<0.05).

Conclusions: TO901317 attenuated the more serious impairment of spatial exploration, learning and memory in transgenic AD mice induced by CRD, and the mechanism may be that TO901317 could activate the LXR-β/RXR-α/ABCA1 transmembrane transport system, promote the cholesterol efflux, and decreased caveolin-1, APP and BACE1, further reduce Aβ42 in the brains.

Introduction: Recent work has shown an association between cognitive and visual impairments and two main theories were advanced, namely the sensory deprivation and the common cause theories. Most studies considered only basic visual functions such as visual acuity or visual field size and evaluated the association with dementia.

Objectives: To reconcile between these theories and to test the link between visual and cognitive decline in mildly cognitive impaired people.

Methods: We employed a battery of 19 visual tasks on 39 older adults with mild cognitive impairment and 91 without any evidence of cognitive decline, as measured by the Montreal Cognitive Assessment.

Results: Our results show a strong association between visual impairment and mild cognitive impairment. In agreement with previous results with younger and healthy older adults, we found also only weak correlations between most tests in older adults with mild cognitive impairment.

Conclusion: Our results suggest that visual and cognitive abilities decline simultaneously, but they do so independently across visual and cognitive functions and across participants.