Dementia prevention and reserve against neurodegenerative disease

Application of Natural Products in Neurodegenerative Diseases by Intranasal Administration: A Review

Natural products derived from traditional Chinese medicine have received significant attention as potential treatments for neurodegenerative disorders due to their wide availability, demonstrated efficacy, and favorable safety profiles. Intranasal delivery provides distinct advantages for targeting the central nervous system (CNS), enabling direct therapeutic agent delivery to the brain by bypassing the blood-brain barrier (BBB). This review evaluates natural products administered intranasally for neurodegenerative diseases (NDs), highlighting their therapeutic potential and addressing formulation challenges related to physicochemical properties. Strategic optimization approaches are proposed, including novel carrier systems, molecular modifications, and combination therapies. By discussing current difficulties and offering practical recommendations, this review aims to encourage further scholarly research and clinical application.

Comprehensive evaluation of AChE inhibition by Eulophia ochreata extract utilizing in silico, ex vivo, and in vivo zebrafish models

Dementia commonly accompanies various neurodegenerative conditions, notably Alzheimer's disease. The pursuit of natural therapies for these diseases and their related symptoms has garnered widespread global interest. The present study aimed to explore the potential of Eulophia ochreata L. extract, containing phenanthrene active compounds, as an acetylcholinesterase (AChE) inhibitor. Analytical techniques confirmed the presence of phenanthrene compounds in the extract, which were then screened for AChE inhibition through molecular docking, ex vivo assays, and scopolamine-induced cognitive deficits in zebrafish larvae. These phenanthrene compounds, found in the extract of Eulophia ochreata L., exhibited a similar affinity for AChE as the standard drug Donepezil, with comparable interactions. Ex vivo assays using zebrafish larvae lysate and mouse brain homogenate indicated dose-dependent AChE inhibition with increasing extract concentrations. Behavioral assessments, including T and Y maze tests, revealed significant cognition improvement in extract-treated larvae having scopolamine-induced cognitive dysfunction, particularly at 1.3 µg/mL concentration. The combined results from molecular docking, ex vivo assays, and in vivo cognition deficit models underscored the potential of Eulophia ochreata L. extract as an AChE inhibitor, suggesting its phytochemicals could hold therapeutic promise, indicating further validation in mammalian models for translation into clinical therapies.

Assessing Public Awareness of Neuropsychiatric and Cognitive Symptoms of Alzheimer's Disease in the Eastern Region of Saudi Arabia: A Cross-sectional Study

OBJECTIVE

Alzheimer disease (AD) is the most common cause of neurodegenerative dementia; it is expected to see global cases tripling by 2050. This study evaluates public awareness of AD in the Eastern region of Saudi Arabia, highlighting the need to improve background knowledge of AD and assess the impact of public education on early detection and management.

METHODOLOGY

This study was a cross-sectional study that targeted the public in the Eastern region of Saudi Arabia. It was conducted between June 2024 and October 2024. Data were collected using an online questionnaire and analyzed using SPSS software.

RESULTS

Our study involved 814 participants. A significant majority (94.7%) believe that brain-stimulating activities can delay AD onset. However, misconceptions persist, with 49.1% incorrectly thinking that AD can affect those in their 30s or 40s, though 86.9% correctly recognize it primarily affects those over 65 years of age. Awareness of cardiovascular health factors as risks was noted by 68.9% of participants, and 60.2% believed environmental toxins could also be a factor. Key recognized symptoms included difficulty in remembering events (76.5%), planning daily activities (65.4%), handling finances (59.7%), and confusion about time and place (79.7%). Furthermore, 80.1% understood that those with AD might better recall older events. The study also found a reliance on informal information sources, with 51.8% of participants guessing answers about the disease.

CONCLUSIONS

Many participants understand that brain-stimulating activities might delay Alzheimer's onset, but significant misconceptions regarding its typical age of onset persist. Education programs using reliable sources are crucial for improving community understanding and management of the disease.

Memory network and cognitive reserve are associated with preserved and stimulated cholinergic neurotransmission

The cholinergic system plays a central role in cognition and neural function, and, in Alzheimer disease (AD) and Lewy body disease (LBD), it has profound implications for cognitive impairment and dementia. The cholinergic forebrain pathway, innervating the neocortex and limbic system, is crucial for learning, memory, and other essential aspects of cognition and plays a wider role in promoting neuronal plasticity. Given the neuroplasticity processes characterizing the cholinergic regions, this system may be sensitive to modulatory phenomena such as cognitive reserve (CR). The concept of CR has been introduced to account for the fact that individual clinical presentation might be milder than expected based on neuropathology. This mismatch can be explained by individual brain reserve (BR) buildup on life experiences, lifestyles, and neurobiologic factors that are associated with resilience. Sparse findings exist suggesting that the CR might result in an increased or preserved function of the cholinergic system in AD patients, and compensatory mechanisms in the early stages of LBD. The limited availability of effective treatment for neurodegenerative dementia emphasizes the importance of CR and BR, as they play a major role in delaying or slowing disease onset and progression. This chapter will describe the involvement of the cholinergic system in neurodegenerative diseases and the tools for the in vivo assessment, focusing specifically on the evidence suggesting the possibility of its modulation by CR.

Midlife dynamics of white matter architecture in lexical production

We aimed to examine the white matter changes associated with lexical production difficulties, beginning in midlife with increased naming latencies. To delay lexical production decline, middle-aged adults may rely on domain-general and language-specific compensatory mechanisms proposed by the LARA model (Lexical Access and Retrieval in Aging). However, the white matter changes supporting these mechanisms remains largely unknown. Using data from the CAMCAN cohort, we employed an unsupervised and data-driven methodology to examine the relationships between diffusion-weighted imaging and lexical production. Our findings indicate that midlife is marked by alterations in brain structure within distributed dorsal, ventral, and anterior cortico-subcortical networks, marking the onset of lexical production decline around ages 53-54. Middle-aged adults may initially adopt a "semantic strategy" to compensate for lexical production challenges, but this strategy seems compromised later (ages 55-60) as semantic control declines. These insights underscore the interplay between domain-general and language-specific processes in the trajectory of lexical production performance in healthy aging and hint at potential biomarkers for language-related neurodegenerative pathologies.

Genomic Insights into Dementia: Precision Medicine and the Impact of Gene-Environment Interaction

The diagnosis, treatment, and management of dementia provide significant challenges due to its chronic cognitive impairment. The complexity of this condition is further highlighted by the impact of gene-environment interactions. A recent strategy combines advanced genomics and precision medicine methods to explore the complex genetic foundations of dementia. Utilizing the most recent research in the field of neurogenetics, the importance of precise genetic data in explaining the variation seen in dementia patients can be investigated. Gene-environment interactions are important because they influence genetic susceptibilities and aid in the development and progression of dementia. Modified to each patient's genetic profile, precision medicine has the potential to detect groups at risk and make previously unheard-of predictions about the course of diseases. Precision medicine techniques have the potential to completely transform treatment and diagnosis methods. Targeted medications that target genetic abnormalities will probably appear, providing the possibility for more efficient and customized medical interventions. Investigating the relationship between genes and the environment may lead to preventive measures that would enable people to change their surroundings and minimize the risk of dementia, leading to the improved lifestyle of affected people. This paper provides a comprehensive overview of the genomic insights into dementia, emphasizing the pivotal role of precision medicine, and gene-environment interactions.

A comprehensive analysis of digital health-focused Living Labs: innovative approaches to dementia

The increasing prevalence of dementia demands innovative solutions; however, existing technological products often lack tailored support for individuals living with this condition. The Living Lab approach, as a collaborative innovation method, holds promise in addressing this issue by actively involving end-users in the design and development of solutions adapted to their needs. Despite this potential, the approach still faces challenges due to its lack of recognition as a research methodology and its absence of tailored guidelines, particularly in dementia care, prompting inquiries into its effectiveness. This narrative review aims to fill this gap by identifying and analysing digital health Living Labs focusing on dementia solutions. Additionally, it proposes guidelines for enhancing their operations, ensuring sustainability, scalability, and greater impact on dementia care. Fifteen Living Labs were identified and analyzed. Based on trends, best practices, and literature, the guidelines emphasize user engagement, interdisciplinary collaboration, technological infrastructure, regulatory compliance, transparent innovation processes, impact measurement, sustainability, scalability, dissemination, and financial management. Implementing these guidelines can enhance the effectiveness and long-term impact of Living Labs in dementia care, fostering new collaborations globally.

Mitochondrial Inherited Disorders and their Correlation with Neurodegenerative Diseases

Mitochondria are essential organelles for the survival of a cell because they produce energy. The cells that need more mitochondria are neurons because they perform a variety of tasks that are necessary to support brain homeostasis. The build-up of abnormal proteins in neurons, as well as their interactions with mitochondrial proteins, or MAM proteins, cause serious health issues. As a result, mitochondrial functions, such as mitophagy, are impaired, resulting in the disorders described in this review. They are also due to mtDNA mutations, which alter the heritability of diseases. The topic of disease prevention, as well as the diagnosis, requires further explanation and exploration. Finally, there are treatments that are quite promising, but more detailed research is needed.

Potential Role of Oxidative Stress in the Pathophysiology of Neurodegenerative Disorders

Neurodegeneration causes premature death in the peripheral and central nervous system. Neurodegeneration leads to the accumulation of oxidative stress, inflammatory responses, and the generation of free radicals responsible for nervous disorders like amyotrophic lateral sclerosis, Alzheimer's disease, Parkinson's disease, and Huntington's disorders. Therefore, focus must be diverted towards treating and managing these disorders, as it is very challenging. Furthermore, effective therapies are also lacking, so the growing interest of the global market must be inclined towards developing newer therapeutic approaches that can intercept the progression of neurodegeneration. Emerging evidences of research findings suggest that antioxidant therapy has significant potential in modulating disease phenotypes. This makes them promising candidates for further investigation. This review focuses on the role of oxidative stress and reactive oxygen species in the pathological mechanisms of various neurodegenerative diseases, amyotrophic lateral sclerosis, Alzheimer's disease, Parkinson's disease, and Huntington's disorders and their neuroprotection. Additionally, it highlights the potential of antioxidant-based therapeutics in mitigating disease severity in humans and improving patient compliance. Ongoing extensive global research further sheds light on exploring new therapeutic targets for a deeper understanding of disease mechanisms in the field of medicine and biology targeting neurogenerative disorders.

Are Advanced Clinical Practitioners perfectly placed to re-report neuroimages to support clinical diagnosis of dementia?

With the ageing population, the prevalence of dementia is increasing worldwide. There is an emphasis on early, timely diagnosis and treatment options for people with a dementia yet wait times from referral to diagnosis have increased. Neuroimaging performed by radiologists is utilised to support dementia diagnosis and some patients will already have a CT scan from a pre-existing condition such as stroke. The purpose of this commentary is to consider whether ACPs who specialise in dementia, are perfectly placed to re-report on pre-existing neuroimages to support the clinical diagnosis of dementia.

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.

The Burden of Dementia Spectrum Disorders and Associated Comorbid and Demographic Features

Dementia spectrum disorders (DSDs) are a major cause of mortality and disability worldwide. DSDs encompass a large group of medical conditions that all ultimately lead to major functional and cognitive decline and disability. Demographic and comorbid conditions that are associated with DSDs have significant prognostic and preventive implications. In this article, we will discuss the global and regional burden of DSDs and cover key demographic and clinical conditions linked with DSDs. In the absence of disease-modifying treatments, the role of primary prevention has become more prominent. Implementation of preventive measures requires an understanding of predisposing and exacerbating factors.

The older adult brain is less modular, more integrated, and less efficient at rest: A systematic review of large-scale resting-state functional brain networks in aging

The literature on large-scale resting-state functional brain networks across the adult lifespan was systematically reviewed. Studies published between 1986 and July 2021 were retrieved from PubMed. After reviewing 2938 records, 144 studies were included. Results on 11 network measures were summarized and assessed for certainty of the evidence using a modified GRADE method. The evidence provides high certainty that older adults display reduced within-network and increased between-network functional connectivity. Older adults also show lower segregation, modularity, efficiency and hub function, and decreased lateralization and a posterior to anterior shift at rest. Higher-order functional networks reliably showed age differences, whereas primary sensory and motor networks showed more variable results. The inflection point for network changes is often the third or fourth decade of life. Age effects were found with moderate certainty for within- and between-network altered patterns and speed of dynamic connectivity. Research on within-subject bold variability and connectivity using glucose uptake provides low certainty of age differences but warrants further study. Taken together, these age-related changes may contribute to the cognitive decline often seen in older adults.

Modifiable contributing factors to COVID-19: A comprehensive review

The devastating complications of coronavirus disease 2019 (COVID-19) result from an individual's dysfunctional immune response following the initial severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Multiple toxic stressors and behaviors contribute to underlying immune system dysfunction. SARS-CoV-2 exploits the dysfunctional immune system to trigger a chain of events ultimately leading to COVID-19. The current study identifies eighty immune system dysfunction-enabling toxic stressors and behaviors (hereafter called modifiable contributing factors (CFs)) that also link directly to COVID-19. Each CF is assigned to one of the five categories in the CF taxonomy shown in Section 3.3.: Lifestyle (e.g., diet, substance abuse); Iatrogenic (e.g., drugs, surgery); Biotoxins (e.g., micro-organisms, mycotoxins); Occupational/Environmental (e.g., heavy metals, pesticides); Psychosocial/Socioeconomic (e.g., chronic stress, lower education). The current study shows how each modifiable factor contributes to decreased immune system capability, increased inflammation and coagulation, and increased neural damage and neurodegeneration. It is unclear how real progress can be made in combatting COVID-19 and other similar diseases caused by viral variants without addressing and eliminating these modifiable CFs.

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.

Cognitive Reserve Modulates Brain Structure and Cortical Architecture in the Alzheimer's Disease

BACKGROUND

Cognitive reserve (CR) explains the individual resilience to neurodegeneration.

OBJECTIVE

The present study investigated the effect of CR in modulating brain cortical architecture.

METHODS

278 individuals [110 Alzheimer's disease (AD), 104 amnestic mild cognitive impairment (aMCI) due to AD, 64 healthy subjects (HS)] underwent a neuropsychological evaluation and 3T-MRI. Cortical thickness (CTh) and fractal dimension (FD) were assessed. Years of formal education were used as an index of CR by which participants were divided into high and low CR (HCR and LCR). Within-group differences in cortical architecture were assessed as a function of CR. Associations between cognitive scores and cortical measures were also evaluated.

RESULTS

aMCI-HCR compared to aMCI-LCR patients showed significant decrease of CTh in the right temporal and in the left prefrontal lobe. Moreover, they showed increased FD in the right temporal and in the left temporo-parietal lobes. Patients with AD-HCR showed reduced CTh in several brain areas and reduced FD in the left temporal cortices when compared with AD-LCR subjects. HS-HCR showed a significant increase of CTh in prefrontal areas bilaterally, and in the right parieto-occipital cortices. Finally, aMCI-HCR showed significant positive associations between brain measures and memory and executive performance.

CONCLUSION

CR modulates the cortical architecture at pre-dementia stage only. Indeed, only patients with aMCI showed both atrophy (likely due to neurodegeneration) alongside richer brain folding (likely due to reserve mechanisms) in temporo-parietal areas. This opposite trend was not observed in AD and HS. Our data confirm the existence of a limited time-window for CR modulation at the aMCI stage.

Dual-Task Exercise to Improve Cognition and Functional Capacity of Healthy Older Adults

Background

It has been suggested that physical inactivity and lack of stimulating cognitive activity are the two most significant modifiable risk factors to impair cognitive function. Although many studies that investigated the cognitive effects of physical exercise and cognitive stimuli in dual-task conditions showed improved cognitive performance, others have not confirmed these findings. The main aim of the present work is to analyze the effects of a dual-task multimodal physical exercise training, at moderate intensity, and cognitive stimulation on cognitive and physical function in healthy older adults.

Methods

This clinical trial was registered on the Brazilian Registry of Clinical Trials (RBR-9zrx3d). Here we tested the effects of a dual-task multimodal physical exercise training, at moderate intensity, on cognitive and physical function and quality of life in community dwelling older adults. The training protocol included 24 group sessions, 2/week, per 75 min. Cognition was assessed using CANTAB automated neuropsychological tests and Functional Capacity to Exercise tests. Performance was compared from baseline to post intervention and to a non-exercise control group using Mixed Linear Model for repeated measures.

Results

Control (CG) and dual-task (DTEx) groups progressed differentially over time on performance of episodic memory, sustained visual attention, functional mobility, cardiorespiratory fitness, lower limbs strength resistance, agility, quality of life and dual-task performance with significant improved DTEx performance. Control group did not show any significant changes on these tests except for showing a reduction in dual-task performance.

Conclusion

We suggest that the dual-task combination of multisensory cognitive stimulation and multimodal moderate physical exercise training, twice a week, may be adopted as an effective program to reduce progression of age-related cognitive decline and improve physical fitness and quality of life on healthy older adults.

Clinical Trial Registration

Brazilian Registry of Clinical Trials: https://ensaiosclinicos.gov.br/rg/RBR-9zrx3d -UTN code: U1111-1233-6349.