Social Aspects of Dementia Prevention from a Worldwide to National Perspective: A Review on the International Situation and the Example of Italy

Hypertension & dementia: Pathophysiology & potential utility of antihypertensives in reducing disease burden

Dementia is a common cause of disability and dependency among the elderly due to its progressive neurodegenerative nature. As there is currently no curative therapy, it is of major importance to identify new ways to reduce its prevalence. Hypertension is recognised as a modifiable risk factor for dementia, particularly for the two most common subtypes; vascular dementia (VaD) and Alzheimer's disease (AD). From the current literature, identified through a comprehensive literature search of PubMed and Cochrane Library, this review aims to establish the stage in adulthood when hypertension becomes a risk for cognitive decline and dementia, and whether antihypertensive treatment is effective as a preventative therapy. Observational studies generally found hypertension in mid-life (age 45-64) to be correlated with an increased risk of cognitive decline and dementia incidence, including both VaD and AD. Hypertension manifesting in late life (age ≥ 65) was demonstrated to be less of a risk, to the extent that incidences of high blood pressure (BP) in the very elderly (age ≥ 75) may even be related to reduced incidence of dementias. Despite the evidence linking hypertension to dementia, there were conflicting findings as to whether the use of antihypertensives was beneficial for its prevention and this conflicting evidence and inconsistent results could be due to the methodological differences between the reviewed observational and randomised controlled trials. Furthermore, dihydropyridine calcium channel blockers and potassium-sparing diuretics were proposed to have neuroprotective properties in addition to BP lowering. Overall, if antihypertensives are confirmed to be beneficial by larger-scale homogenous trials with longer follow-up durations, treatment of hypertension, particularly in mid-life, could be an effective strategy to considerably lower the prevalence of dementia. Furthermore, greater clarification of the neuroprotective properties that some antihypertensives possess will allow for better clinical practice guidance on the choice of antihypertensive class for both BP lowering and dementia prevention.

The Dysregulated MAD in Mad: A Neuro-theranostic Approach Through the Induction of Autophagic Biomarkers LC3B-II and ATG

The word mad has historically been associated with the psyche, emotions, and abnormal behavior. Dementia is a common symptom among psychiatric disorders or mad (schizophrenia, depression, bipolar disorder) patients. Autophagy/mitophagy is a protective mechanism used by cells to get rid of dysfunctional cellular organelles or mitochondria. Autophagosome/mitophagosome abundance in autophagy depends on microtubule-associated protein light chain 3B (LC3B-II) and autophagy-triggering gene (ATG) which functions as an autophagic biomarker for phagophore production and quick mRNA disintegration. Defects in either LC3B-II or the ATG lead to dysregulated mitophagy-and-autophagy-linked dementia (MAD). The impaired MAD is closely associated with schizophrenia, depression, and bipolar disorder. The pathomechanism of psychosis is not entirely known, which is the severe limitation of today's antipsychotic drugs. However, the reviewed circuit identifies new insights that may be especially helpful in targeting biomarkers of dementia. Neuro-theranostics can also be achieved by manufacturing either bioengineered bacterial and mammalian cells or nanocarriers (liposomes, polymers, and nanogels) loaded with both imaging and therapeutic materials. The nanocarriers must cross the BBB and should release both diagnostic agents and therapeutic agents in a controlled manner to prove their effectiveness against psychiatric disorders. In this review, we highlighted the potential of microRNAs (miRs) as neuro-theranostics in the treatment of dementia by targeting autophagic biomarkers LC3B-II and ATG. Focus was also placed on the potential for neuro-theranostic nanocells/nanocarriers to traverse the BBB and induce action against psychiatric disorders. The neuro-theranostic approach can provide targeted treatment for mental disorders by creating theranostic nanocarriers.

Brain metabolism in Alzheimer's disease: biological mechanisms of exercise

Alzheimer's disease (AD) is a major subtype of neurodegenerative dementia caused by long-term interactions and accumulation of multiple adverse factors, accompanied by dysregulation of numerous intracellular signaling and molecular pathways in the brain. At the cellular and molecular levels, the neuronal cellular milieu of the AD brain exhibits metabolic abnormalities, compromised bioenergetics, impaired lipid metabolism, and reduced overall metabolic capacity, which lead to abnormal neural network activity and impaired neuroplasticity, thus accelerating the formation of extracellular senile plaques and intracellular neurofibrillary tangles. The current absence of effective pharmacological therapies for AD points to the urgent need to investigate the benefits of non-pharmacological approaches such as physical exercise. Despite the evidence that regular physical activity can improve metabolic dysfunction in the AD state, inhibit different pathophysiological molecular pathways associated with AD, influence the pathological process of AD, and exert a protective effect, there is no clear consensus on the specific biological and molecular mechanisms underlying the advantages of physical exercise. Here, we review how physical exercise improves crucial molecular pathways and biological processes associated with metabolic disorders in AD, including glucose metabolism, lipid metabolism, Aβ metabolism and transport, iron metabolism and tau pathology. How metabolic states influence brain health is also presented. A better knowledge on the neurophysiological mechanisms by which exercise improves AD metabolism can contribute to the development of novel drugs and improvement of non-pharmacological interventions.

Collaborative Learning through a Virtual Community of Practice in Dementia Care Support: A Scoping Review

The aim of this scoping review was to identify, synthesize, and report research on reflective collaborative learning through virtual communities of practice (vCoP), which, to our knowledge, is scarce. A second aim was to identify, synthesize, and report research on the facilitators and barriers associated with resilience capacity and knowledge acquisition through vCoP. The literature was searched in PsycINFO, CINAHL, Medline, EMBASE, Scopus, and Web of Science. The Preferred Reporting Items for Systematic Reviews (PRISMA) and Meta-Analyses for Scoping Reviews (ScR) framework guided the review. Ten studies were included in the review, seven quantitative and three qualitative studies, written in English and published from January 2017 to February 2022. The data were synthesized using a numerical descriptive summary and qualitative thematic analysis. Two themes: 'knowledge acquisition' and 'strengthening resilience capacity' emerged. The literature synthesis provides evidence of a vCoP as a digital space that supports knowledge acquisition and strengthens resilience for persons with dementia, and their informal and formal caregivers. Hence, the use of vCoP seems to be useful for dementia care support. Further studies including less developed countries are, however, needed to enable generalizability of the concept of vCoP across countries.

The Influence of Everyday Acoustic Environments on the Challenging Behavior in Dementia: A Participatory Observation Study in Nursing Homes

Challenging behavior (CB) is a group of behaviors, reactions and symptoms due to dementia, which can be challenging for the caregivers. The study aims to research the influence of acoustics on CB in people with dementia (PwD). An ethnographic method was used to study the daily life of PwD in their nursing homes with a specific focus on how people react to everyday environmental sounds. Thirty-five residents were included in the sample based on purposeful, homogeneous group characteristics and sampling. Empirical data were collected using 24/7 participatory observations. The collected data were analyzed using a phenomenological-hermeneutical method: a naïve understanding, a structural analysis and a comprehensive understanding. The result shows that the onset of CB depends on whether the resident feels safe and is triggered by an excess or lack of stimuli. The excess or shortage of stimuli and whether and when it affects a person is personal. It depends on various factors, the person's state and the time of day, the nature of the stimuli, familiarity, or strangeness is also a determining factor for the onset and progression of CB. The results can form an essential basis for developing soundscapes to make the PwD feel safe and reduce CB.

A Qualitative Literature Search and Pilot Study of Online Support Groups for Patients With Dementia and Their Carers

The ever-growing group of people living with dementia (PLWD) and their relatives face great challenges. The Covid 19 pandemic has once again placed a particular challenge on this vulnerable group. What started a decade earlier with telephone-based support groups experienced a real push during the pandemic in the form of video-based self-help services. The aim of this qualitative literature search in MEDLINE, EMBASE, CINAHL, and PsycINFO with keywords related to online, support group, caregiver, and dementia was to collect the reported experiences by the end of 2022. Peer reviewed journal papers were included when published and written in English. After the joint decision of two reviewers, it was decided to only include studies that were published in Medline. The results of the literature search are compared with experiences of the participants in a presentation group that was transformed into an online group at the time of the COVID-19 pandemic via Zoom. In search yielded a total of 129 articles. 113 articles described different types of interventions, 30 of which had a randomized design. The qualitative literature search showed on the one hand a high interest in online support groups but on the other hand that the effectiveness and efficacy in randomized trials is much less clear. In addition, we investigated the assessments and experiences of the participants in a presentation group that was transformed into an online group at the time of the COVID-19 pandemic via Zoom. This study demonstrates that PLWD and carers on virtual group meetings can express significant emotive capacity and enhanced connectivity with one another despite a diagnosis of mild to moderate dementia. Further research on entry criteria, concerns about online support services in general and necessary support for use is essential to develop the time- and location-independent possibility of video-based online self-help into an important form of support for both PLWD and their caregivers as an additional support option independent of exceptional pandemic situations.

Concepts of dementia prevention in the health promotion among older adults: A narrative review

The number of older adults with dementia is predicted to markedly increase in the coming decades. A person suffers from dementia every 3 seconds globally, and one out of every 7 people suffers from dementia in Taiwan. The purpose of this narrative review is to integrate existing concepts of dementia prevention into health promotion and improve older adults' quality of life. This narrative review was performed using the PubMed database by searching for basic research and systematic reviews on dementia prevention and health promotion among older adults. We established a framework for dementia prevention and health promotion with regard to the physical, mental, spiritual, and social health aspects. We identified the following strategies related to older adults towards dementia prevention and health promotion in follows: Physical health promotion: cognitive activities, physical activities, body mass index, balanced diet, rainbow diet, Mediterranean diet, dietary approaches to stop hypertension diet, mind diet, no smoking and drinking, avoiding the "three highs" (i.e., hyperglycemia, hyperlipidemia, and hypertension), and head trauma; Mental health promotion: Positive thinking, Brief Symptom Rating Scale (BSRS-5), depression scale, and ascertained dementia 8 questionnaire (AD8) screening; Spiritual health promotion: religious beliefs, spiritual music, meditative activities, mindfulness, yoga, Qi-gong, Tai-chi, and Baduanjin; and Social health promotion: A supportive family system, socialization, social support, social networks, social interaction, and social participation. The conclusion of this narrative review was to integrate the concepts of dementia prevention and health promotion among older adults.

Self Assessment Memory Scale (SAMS), a new simple method for evaluating memory function

We have developed a new method for easy self-assessment of changes in memory recall impairment, which can be used during the very early stages of dementia. An 8-picture recall and a 16-word regression were assessed, respectively, and the index was calculated by adding up the ratio of correct responses to both tests. A total of 85 subjects including 12 MCI, 8 AD, and 65 older persons with normal cognitive function were evaluated, and the correlation with the WMS-R Logical Memory II score was examined. The results showed that there was a statistically significant correlation between the 8-picture recall (R = 0.872, p < 0.0001) and the index (R = 0.857, p < 0.0001), respectively, with the Logical Memory score. We have named this index as Self Assessment Memory Scale (SAMS), and are now developing a digital tool to enable easy and self-administered evaluation of recall.

Social Robotics and Dementia: Results from the eWare Project in Supporting Older People and Their Informal Caregivers

The aim of this paper is to describe the results collected with the Italian study conducted within eWare project, aimed at supporting the autonomy and health of the older people affected by dementia and their informal caregivers, through the use of an innovative system based on a social robot and a sensorized environmental infrastructure. Nine dyads of older participants with their caregivers were enrolled in testing the system for 6 months. The results show a positive impact of the system in supporting the achievement of personal goals of the participants, as well as in supporting the quality of life of the informal caregivers. Nevertheless, the impact of the system in reducing the caregivers' burden needs to be deeply investigated. This research highlights the potential of the eWare system but modifications will have to be made, especially on the interactivity capabilities, in order to meet the peculiar needs and wishes of older people with dementia and to favor the long-term use of the system.

Impact of arterial hypertension and its management strategies on cognitive function and dementia: a comprehensive umbrella review

INTRODUCTION

Cognitive decline and dementia recognize multiple risk factors and pathophysiological mechanisms, often involved simultaneously with complex interactions. Several studies have shown that both arterial hypertension and hypotension are associated with a greater risk of cognitive decline and dementia, but clinical evidence on this point is conflicting. Our aim was to conduct an umbrella review on cognitive function, dementia, and blood pressure, with particular attention to epidemiological, prognostic and therapeutic aspects.

EVIDENCE ACQUISITION

We conducted a dedicated literature search on PubMed for systematic reviews and meta-analyses that focused on arterial pressure, hypertension, hypotension and similar conditions, and cognitive function, cognitive decline and dementia. The internal validity of systematic reviews and meta-analyses was formally analyzed using the OQAQ tool. The umbrella review was planned in accordance with current international recommendations and was described as specified by the PRISMA guidelines.

EVIDENCE SYNTHESIS

Seventeen systematic reviews (including 13 meta-analyses) were included, for a total of 675 clinical studies and over 1 million patients. Hypertension results to be associated with a lower risk of Alzheimer's dementia, greater risk of vascular dementia and greater risk of cognitive decline. Orthostatic hypotension seems to be associated with greater risk of Alzheimer's dementia, vascular dementia and dementia of Parkinson's disease. Therapy with acetylcholinesterase inhibitors produces lower risk of cardiovascular events, greater risk of hypertension and greater risk of bradycardia, while the anti-hypertensive therapy leads to a lower risk of dementia of all types and lower risk of cognitive decline.

CONCLUSIONS

To date, the evidence on the relationship between blood pressure, cognitive decline and dementia provides somewhat heterogeneous data. Further studies are clearly needed, with explicit inclusion criteria as objective as possible, adequate follow-up and precise characterization of implemented cardiovascular and cognitive treatments.

Inflammatory bowel disease as a new risk factor for dementia

The prognostic impact of inflammatory bowel disease (IBD), chronic inflammatory conditions consisting of ulcerative colitis (UC), and Crohn's disease (CD) on the risk of dementia has been poorly investigated. We evaluated the risk of dementia in IBD patients by a systematic review and meta-analysis of the available data. Three studies, enrolling 121.827 patients [14.839 IBD (12.1%) and 106.961 (87.7%) controls, respectively] were included in the analysis. Of these, 57.7% (n = 8.571) had UC, while 42.2% (n = 6268) had CD. The mean follow-up period was 21.3 years. A random effect model revealed an aHR of 1.52 (95% CI 1.04-2.020, p = 0.01; I² = 91.1%) for dementia in IBD patients. Sensitivity analysis confirmed yielded results. Subjects having a CD showed an aHR for dementia of 1.48 (95% CI 1.07-2.03, p = 0.001, I² = 68.9%), while the risk among those with a history of UC did not reach the statistical significance (aHR: 1.47, 95% CI 0.95-2.82, p = 0.81, I² = 89.9%). IBD males had an increased risk of dementia compared to women. IBD patients and in particular those with CD have an increased risk of dementia in the long-term period.

The Role of Medical Acupuncture Therapy in Alzheimer's Disease

Objective: Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by memory deficits and other cognitive disorders, which can be accompanied by personality changes. Long-term use of medications available to treat AD today have a variety of side-effects. Acupuncture, as a nonpharmacologic therapeutic modality providing stimulation at acupuncture points, using filiform needles, has been widely tested and used to manage of AD and can be a therapeutic option, considering its effectiveness and lack of side-effects. Methods: This literature review examines the role of acupuncture in AD treatment. Results: Acupuncture can ameliorate AD symptoms through decreasing amyloid-β protein, reducing neuroinflammation, enhancing the antioxidant system, improving neurogenesis, enhancing prosurvival protein, reducing proapoptotic protein, and regulating brain energy metabolism. Conclusions: According to various research findings, acupuncture may be a therapeutic choice for addressing AD that avoids the long-term side-effects caused by medical therapy.

An App-Based Mindfulness-Based Self-compassion Program to Support Caregivers of People With Dementia: Participatory Feasibility Study

BACKGROUND

The number of persons with dementia is steadily growing, as is the number of individuals supporting persons with dementia. Primary caregivers of persons with dementia are most often family members or spouses of the persons with dementia, and they are more likely to experience increased stress and other negative effects than individuals who are not primary caregivers. Although in-person support groups have been shown to help buffer the negative impacts of caregiving, some caregivers live in isolated or rural communities and are unable to make the burdensome commitment of traveling to cities. Using an interdisciplinary approach, we developed a mobile smartphone support app designed for primary caregivers of persons with dementia, with the goal of reducing caregiver burden and easing stress. The app features a 12-week intervention, largely rooted in mindfulness-based self-compassion (MBSC), because MBSC has been linked to minimizing stress, depression, and anxiety.

OBJECTIVE

The primary objectives of our program are twofold: to explore the feasibility of a 12-week mobile support program and to conduct an initial efficacy evaluation of changes in perceived caregiver burden, coping styles, and emotional well-being of caregivers before and after the program.

METHODS

Our feasibility study used a 2-phase participatory pretest and posttest design, focusing on acceptability, demand, practicality, implementation, and efficacy. At phase I, we recruited 57 primary caregivers of persons with dementia (mean age 76.3, SD 12.9 years), comprising spouses (21/57, 37%), children (21/57, 37%), and friends or relatives (15/57, 26%) of persons with dementia, of whom 29 (51%) completed all measures at both pre- and postprogram. The content of the program featured a series of MBSC podcasts. Our primary outcome measure was caregiver burden, with secondary outcome measures including coping styles and emotional well-being. Daily ecological momentary assessments enabled us to ask participants, "How are you feeling today?" Phase II of our study involved semistructured follow-up interviews with most participants (n=21) who completed phase I.

RESULTS

Our findings suggest that our app or program meets the feasibility criteria examined. Notably, participants generally accepted the program and believed it could be a useful resource. Emotional well-being increased significantly (P=.04), and emotion-based coping significantly decreased (P=.01). Participants generally considered the app or program to be a helpful resource.

CONCLUSIONS

Although there were no significant changes in caregiver burden, we were encouraged by the increased emotional well-being of our participants following the completion of our program. We also conclude that our app or program demonstrated feasibility (ie, acceptability, practicality, implementation, and efficacy) and can provide a much-needed resource for primary caregivers of persons with dementia. In the subsequent version of the program, we will respond to participant feedback by incorporating web-based weekly sessions and incorporating an outcome measure of self-compassion.

Different Age Related Neurological and Cardiac Effects of Verapamil on a Transgenic Mouse Model of Alzheimer's Disease

Dementias are the third cause of the disability-adjusted life-years (DALYs) worldwide with Alzheimer’s (AD) having the highest prevalence. Despite ample research in the field, therapeutic options are limited. However, with the increase in lifespan, a larger number of AD patients will receive other medication for the evermore-increased number of comorbidities that such patients face. The purpose of this study was to evaluate the neurological and cardiac effects of verapamil, on C57BL/6J-TgN (Thy1-APPKM670/671NL; Thy1-PS1L166P (APP) mice. The daily administration of 3.5mg/kg of verapamil for 28 days revealed different effects on young and aged APP mice. While young animals showed less anxiety and improved short-term memory with minimal cardiac effects (an increase in the duration of ventricular depolarization), aged ones did not present behavioral improvements, but with a decrease in the duration of ventricular depolarizing. Repolarization effects of verapamil were similar in young and aged animals, except for the duration of the ST segment that was longer in aged animals. Considering our results, the use of calcium blockers in AD patients should take into consideration the stage of the disease, as different effects could be seen at different stages of AD, in our model.

Expanding role of nurses in management of dementia in geriatrics: improving well-being of geriatric patients through quality nursing care

The potential nurses role to include the recognition and management of dementia has been acknowledged. Practice Nurses are well-positioned to provide comprehensive dementia information and support so that people living with dementia are better equipped to self-manage their health and live well with dementia. However, treatment of geriatric dementia has become difficult owing to co-morbidities and cognitive and physical deterioration of these patients. Thus, geriatric dementia patients require special attention during care in homes and clinical settings. In modern medical practice, the role of nurse has become dynamic, ranging from education and personal care. The profession of nursing is considered as critical to meets the needs of the elderly population with dementia and ensure the delivery of high-quality care. Since nurses play such an important role in caring for these individuals, comprehensive reviews lack on their role and experience in geriatric dementia treatment and issues. This review summarizes the expanding role of nurses in the management of geriatric dementia in terms of nurse's knowledge, role, communication, attitude and maintaining patient's quality of life through diverse activities. Furthermore, we also explain the future direction for improving the nursing care to treat dementia in elderly population.

Extracting Robust Biomarkers From Multichannel EEG Time Series Using Nonlinear Dimensionality Reduction Applied to Ordinal Pattern Statistics and Spectral Quantities

In this study, ordinal pattern analysis and classical frequency-based EEG analysis methods are used to differentiate between EEGs of different age groups as well as individuals. As characteristic features, functional connectivity as well as single-channel measures in both the time and frequency domain are considered. We compare the separation power of each feature set after nonlinear dimensionality reduction using t-distributed stochastic neighbor embedding and demonstrate that ordinal pattern-based measures yield results comparable to frequency-based measures applied to preprocessed data, and outperform them if applied to raw data. Our analysis yields no significant differences in performance between single-channel features and functional connectivity features regarding the question of age group separation.

Effects of Chinese herbal medicines on dementia risk in patients with sleep disorders in Taiwan

ETHNOPHARMACOLOGICAL RELEVANCE

Sleep disorders affect an estimated 150 million people worldwide and result in adverse health, safety, and work performance-related outcomes that have important economic consequences. In Taiwan, Chinese herbal medicine (CHM) is a complementary natural medicine and has been widely used as an adjunctive therapy.

AIM OF THE STUDY

This study aimed to investigate the effect of CHM on dementia risk in patients with sleep disorders in Taiwan.

MATERIALS AND METHODS

We identified 124,605 patients with sleep disorders between the ages of 20 and 60 years. Of these, 5876 CHM users and 5876 non-CHM users were matched according to age and gender. The chi-squared test, Cox proportional hazard model, Kaplan-Meier method, and log-rank test were used for the comparisons. Association rule mining and network analysis were applied to determine a CHM pattern specialized for sleep disorders.

RESULTS

More CHM users did not use sleeping pills than non-CHM users. CHM users had a lower risk of dementia than non-CHM users after adjusting for age, gender, and sleeping pill use (hazard ratio (HR): 0.469, 95% CI = 0.289-0.760; p-value = 0.002). The cumulative incidence of dementia was lower among CHM users (long-rank test, p-value < 0.001). Association rule mining and network analysis showed that Ye-Jiao-Teng (YJT; Caulis Polygoni Multiflori; Polygonum multiflorum Thunb), Suan-Zao-Ren-Tang (SZRT), Jia-Wei-Xiao-Yao-San (JWXYS), He-Huan-Pi (HHP; Cortex Albizziae; Albizia julibrissin Durazz.), and Suan-Zao-Ren (SZR; Semen Zizyphi Spinosae; Ziziphus jujuba Mill.) were important CHMs for patients with sleep disorders in Taiwan.

CONCLUSIONS

A comprehensive list of herbal medicines may be useful for the clinical treatment of patients with sleep disorders, and for future scientific investigations into the prevention of dementia in these patients.

Ameliorative Effect of Necrosulfonamide in a Rat Model of Alzheimer's Disease: Targeting Mixed Lineage Kinase Domain-like Protein-Mediated Necroptosis

Alzheimer's disease (AD) is a progressively debilitating neurodegenerative disorder that has no effective remedy, so far, with available therapeutic modalities being only symptomatic and of modest efficacy. Necroptosis is a form of controlled cell death with a recently emerging link to the pathogenesis of several neurodegenerative diseases. This study investigated the role of necroptosis in the pathogenesis of AD and evaluated the potential beneficial effect of the necroptosis inhibitor, necrosulfonamide (NSA), in a rat model of AD. AD was induced by oral administration of AlCl₃ (17 mg/kg/day) for 6 consecutive weeks. Administration of NSA (1.65 mg/kg/day) intraperitoneally for 6 weeks significantly amended AlCl₃-induced spatial learning and memory deficits, as demonstrated by enhanced rat performance in Morris water and Y-mazes. NSA alleviated the abnormally high hippocampal expression of tumor necrosis factor-alpha (TNF-α), β-site amyloid precursor protein cleaving enzyme 1 (BACE1), β-amyloid, glycogen synthase kinase-3β (GSK-3β), phosphorylated tau protein, and acetylcholinesterase with concordant replenishment of acetylcholine. The amendments of AD perturbations achieved by NSA correlated with its inhibitory effect on the phosphorylation of the key necroptotic executioner, mixed lineage kinase domain-like protein (MLKL). Histopathological alterations supported the biochemical findings. In conclusion, NSA treatment represents a promising anti-Alzheimer's approach, mitigating AD neuropathologies via targeting MLKL-dependent necroptosis.

The Differential Effect of Treadmill Exercise Intensity on Hippocampal Soluble Aβ and Lipid Metabolism in APP/PS1 Mice

Alzheimer's disease (AD) is characterized clinically by progressive impairments in learning and memory. Accumulating evidence suggests that regular exercise plays a neuroprotective role in aging-associated memory loss. Our previous study has confirmed that long-term treadmill exercise initiated either before or during the onset of β-amyloid (Aβ) pathology, was beneficial for reducing the levels of soluble Aβ and further improved cognition. In this study, in APP/PS1 mice, we assessed changes in soluble Aβ, and various blood biochemistry and molecular biological indices to assess whether exercise modulated lipid metabolism and thereby decelerated AD progression. Our results show that long-term treadmill exercise reduced the total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels, and increased the level of high-density lipoprotein cholesterol. Exercise also decreased the levels of soluble Aβ1-40 and Aβ1-42, down-regulated retinoid X receptor expression, and up-regulated liver X receptor, Apolipoprotein E, Low density lipoprotein receptor, Low density lipoprotein receptor-related protein 1, and ATP-binding cassette transporter A1 expression. This indicates that long-term treadmill exercise alters the lipoprotein content, increases lipid metabolism and cholesterol transportation, reduces the soluble Aβ, and therein plays an important neuroprotective role and delays AD progression. We further show that medium exercise intensity (60%-70% of maximal oxygen uptake) was more efficacious in increasing lipid metabolism and reducing blood lipid levels and soluble Aβ levels, than low-intensity exercise (45-55% of maximal oxygen uptake). This research has broad prospects and implications, and offers a theoretical basis for the prevention of AD.