Impact of a short-duration experiential learning activity on DPT students' attitudes toward patients living with a dementia

Healthcare practitioners (HCP) have expressed inadequate preparation in providing care to patients living with a dementia. Research suggests experiential learning activities (ELAs) can improve HCP knowledge and comfort toward this population. The purpose of this study was to evaluate the impact of a short-duration (2-hour) dementia ELA on Doctor of Physical Therapy (DPT) students' knowledge and comfort toward individuals living with a dementia. Participants included a sample of first-year DPT students (n=82).  In this pre-experimental, single-site, longitudinal study, students participated in an ELA at a memory care facility. They completed a dementia knowledge and comfort survey pre-(T1) and post-ELA(T2), as well as prior to their first clinical experience (nine months post-ELA; T3). Pre- and post-survey analysis demonstrated significant improvements between T1 to T2 and T1 to T3 with overall effect sizes ranging from very large (d=1.256) to huge (d=1.520). There were no significant differences between T2 to T3 analysis. Students demonstrated positive improvements in attitudes toward individuals living with a dementia following this ELA. Improvements were maintained over time. An ELA as short as two hours may improve person-centered care for patients living with a dementia. These types of activities should be considered for inclusion in DPT curricula.

Deep brain stimulation for Alzheimer's disease - current status and next steps

INTRODUCTION

Alzheimer's disease (AD) requires novel therapeutic approaches due to limited efficacy of current treatments.

AREAS COVERED

This article explores AD as a manifestation of neurocircuit dysfunction and evaluates deep brain stimulation (DBS) as a potential intervention. Focusing on fornix-targeted stimulation (DBS-f), the article summarizes safety, feasibility, and outcomes observed in phase 1/2 trials, highlighting findings such as cognitive improvement, increased metabolism, and hippocampal growth. Topics for further study include optimization of electrode placement, and the role of stimulation-induced autobiographical-recall. Nucleus basalis of Meynert (DBS-NBM) DBS is also discussed and compared with DBS-f. Challenges with both DBS-f and DBS-NBM are identified, emphasizing the need for further research on optimal stimulation parameters. The article also reviews alternative DBS targets, including medial temporal lobe structures and the ventral capsule/ventral striatum.

EXPERT OPINION

Looking ahead, a phase-3 DBS-f trial, and the prospect of closed-loop stimulation using EEG-derived biomarkers or hippocampal theta activity are highlighted. Recent FDA-approved therapies and other neuromodulation techniques like temporal interference and low-intensity ultrasound are considered. The article concludes by underscoring the importance of imaging-based diagnosis and staging to allow for circuit-targeted therapies, given the heterogeneity of AD and varied stages of neurocircuit dysfunction.

DNAJB8 oligomerization is mediated by an aromatic-rich motif that is dispensable for substrate activity

J-domain protein (JDP) molecular chaperones have emerged as central players that maintain a healthy proteome. The diverse members of the JDP family function as monomers/dimers and a small subset assemble into micron-sized oligomers. The oligomeric JDP members have eluded structural characterization due to their low-complexity, intrinsically disordered middle domains. This in turn, obscures the biological significance of these larger oligomers in protein folding processes. Here, we identified a short, aromatic motif within DNAJB8 that drives self-assembly through π-π stacking and determined its X-ray structure. We show that mutations in the motif disrupt DNAJB8 oligomerization in vitro and in cells. DNAJB8 variants that are unable to assemble bind to misfolded tau seeds more specifically and retain capacity to reduce protein aggregation in vitro and in cells. We propose a new model for DNAJB8 function in which the sequences in the low-complexity domains play distinct roles in assembly and substrate activity.

A bidirectional link between sulfatide and Alzheimer's disease

Reduced sulfatide level is found in Alzheimer's disease (AD) patients. Here, we demonstrate that amyloid precursor protein (APP) processing regulates sulfatide synthesis and vice versa. Different cell culture models and transgenic mice models devoid of APP processing or in particular the APP intracellular domain (AICD) reveal that AICD decreases Gal3st1/CST expression and subsequently sulfatide synthesis. In return, sulfatide supplementation decreases Aβ generation by reducing β-secretase (BACE1) and γ-secretase processing of APP. Increased BACE1 lysosomal degradation leads to reduced BACE1 protein level in endosomes. Reduced γ-secretase activity is caused by a direct effect on γ-secretase activity and reduced amounts of γ-secretase components in lipid rafts. Similar changes were observed by analyzing cells and mice brain samples deficient of arylsulfatase A responsible for sulfatide degradation or knocked down in Gal3st1/CST. In line with these findings, addition of sulfatides to brain homogenates of AD patients resulted in reduced γ-secretase activity. Human brain APP level shows a significant negative correlation with GAL3ST1/CST expression underlining the in vivo relevance of sulfatide homeostasis in AD.

Link Between Obsessive-Compulsive Disorder and ApoE Gene Polymorphisms

Objective

Many researchers have considered obsessive compulsive disorder (OCD) to be a neurodegenerative disease just like Alzheimer's disease (AD). The most studied gene in neurodegenerative diseases is apolipoprotein E (ApoE) gene, and ApoE ɛ4 allele in particular. Although a small number of studies have explored the relationship between ApoE gene polymorphisms and OCD, the link between age at onset of OCD, its subtypes and ApoE gene polymorphisms has not been revealed so far. For this purpose, in our study, the relationship of ApoE gene polymorphisms with age at onset of OCD and its subtypes has been investigated to reveal their neurodegenerative connections.

Patients and Methods

ApoE gene polymorphisms of 64 OCD and 28 healthy cases were studied using a LightCycler480 real-time PCR platform.

Results

A statistically significant difference was found between groups of patients with early- and late-onset OCD in terms of age (p = 0.03), educational level (p = 0.00) and marital status (p = 0.002). ApoE ɛ4ɛ4 genotype, the prevalence of which is below 2% in healthy individuals, was not detected in our control groups; however, it was identified in 5.1% of our OCD cases. Correlation analysis revealed the presence of a potentially significant link between the hoarding obsession and presence of the ɛ4ɛ4 genotype. A significant correlation was detected between the presence of the ɛ3ɛ3 allele, the symmetry obsession and associated ordering compulsion in patients with OCD (p<0.005).

Conclusion

The ApoE gene polymorphism profile and age of onset in OCD patients may play critical roles in the development process of neurodegenerative characteristics of the disease. The small number of cases and the inability to perform brain imaging in patients to detect the neurodegenerative link in OCD are limitations of our study. In this respect, we suggest conduction of further studies with a greater number of patients who will also undergo brain imaging studies. In addition, OCD patients have other genes associated with neurodegenerative diseases that can be screened.

Hyperglycemic Neurovasculature-On-A-Chip to Study the Effect of SIRT1-Targeted Therapy for the Type 3 Diabetes "Alzheimer's Disease"

Diabetes mellitus (DM) is closely related to Alzheimer's disease (AD), but individual cellular changes and the possibilities of recovery through molecular level regulation have not been investigated. Here, a neurovasculature-on-a-chip (NV chip) model is presented in which the perfusable brain microvasculature is surrounded by the neurons. Under hyperglycemic conditions, the brain microvasculature shows disruption of barrier function and reduced expression of junctional markers. The neurons show Tau pathology and amyloid-beta (Aß) accumulation. Endothelial cells and neurons in the NV chip show sirtuin 1 (SIRT1) downregulation under hyperglycemic conditions, suggesting SIRT1 as a key regulator of hyperglycemia-induced AD. The recovery of glucose levels rescue SIRT1 expression, suggesting that this type of intervention may rescue the progression of hyperglycemia-mediated AD. Furthermore, the short hairpin RNA (shRNA)-, clustered regularly interspaced short palindromic repeats (CRISPR)-, and pharmaceutics-mediated regulation of SIRT1 regulate the pathophysiology of the brain endothelium and neurons at the functional and molecular levels.

LYECs: lysosome-enhancing compounds as potential therapeutic approaches for Alzheimer disease

More than 55 million people are suffering from Alzheimer's disease (AD), but there is still no effective treatment for it. Therefore, novel therapeutic approaches and regulatory mechanisms of protein quality control need to be further evaluated and dissected. The lysosome is one of the major degradative organelles that maintain cellular homeostasis and protein quality control. In our recent study, we have identified a group of LYsosome-Enhancing Compounds (LYECs), which significantly promote the activation of TFEB (transcription factor EB) and lysosome biogenesis via inhibiting dopamine transporters (DAT). Injection of LH2-051, a member of the LYECs identified in this study, significantly improves learning, memory, and cognitive function of APP-PSEN1 mice, in which the enhanced capability of lysosomal degradation promotes the clearance of amyloid protein aggregates. In summary, this study reports novel mechanisms of neurotransporter-mediated lysosome biogenesis and shows that DAT inhibition can alleviate the pathogenesis of Alzheimer's disease.

ADVIAN: Alzheimer's Disease VGG-Inspired Attention Network Based on Convolutional Block Attention Module and Multiple Way Data Augmentation

Aim: Alzheimer's disease is a neurodegenerative disease that causes 60-70% of all cases of dementia. This study is to provide a novel method that can identify AD more accurately. Methods: We first propose a VGG-inspired network (VIN) as the backbone network and investigate the use of attention mechanisms. We proposed an Alzheimer's Disease VGG-Inspired Attention Network (ADVIAN), where we integrate convolutional block attention modules on a VIN backbone. Also, 18-way data augmentation is proposed to avoid overfitting. Ten runs of 10-fold cross-validation are carried out to report the unbiased performance. Results: The sensitivity and specificity reach 97.65 ± 1.36 and 97.86 ± 1.55, respectively. Its precision and accuracy are 97.87 ± 1.53 and 97.76 ± 1.13, respectively. The F1 score, MCC, and FMI are obtained as 97.75 ± 1.13, 95.53 ± 2.27, and 97.76 ± 1.13, respectively. The AUC is 0.9852. Conclusion: The proposed ADVIAN gives better results than 11 state-of-the-art methods. Besides, experimental results demonstrate the effectiveness of 18-way data augmentation.

ATP-sensitive potassium channels: key players in pathophysiology of many diseases

ATP-sensitive potassium channels have been an intensively studied type of protein complexes incorporated in the cell membrane for several decades. Their unique function makes them special, as they create a connection between the metabolic state and membrane voltage of the cell. This position of a bridge involved in many cellular cascades allow them to participate in various processes at often surprising positions in nearly all organ systems of the body, from the pancreas, heart muscle or retina, to the central nervous system. This review summarizes the most important roles of ATP-sensitive potassium channels focusing on their possible clinical use within particular organ systems.

A new proposal for the causative agent of the sporadic form of Alzheimer's disease

Group B streptococcus (Streptococcus agalactiae) is proposed as causative agent for the development of the sporadic form of Alzheimer's disease. Using a fibrinogen binding protein, aggregates are formed including A-beta. After triggering Alzheimer's disease by the bacterium, the next down-stream events mainly follow the well known so called A-beta hypothesis. The combination of the two hypotheses is able to explain a number of epidemiological and biochemial aspects of Alzheimer's disease.

Very-late-onset psychotic symptoms: psychosis or dementia? A phenomenological approach. A systematic review

Very-late-onset psychotic symptoms (PS) are a common gateway to both neurodegenerative dementias and primary psychiatric disorders. Despite similarities in clinical expression, no consensual guidelines or a specific nosographic framework exist. The purpose of this systematic review is to establish a phenomenological classification of PS among the main neurodegenerative dementias and late psychosis. More specifically, to: 1) allow psychotic phenotypes to be considered according to aetiology; 2) help clinicians screen for psychiatric-type dementia, when appropriate; and 3) justify research into very-late-onset PS in patients with dementias at a pre-clinical cognitive stage in order to establish a nosographic framework for these PS based on the prognosis of dementia.

METHODS

A literature review was conducted to search for very-late-onset PS (>60 years old) in reports of late-onset (known as primary) psychoses, Alzheimer-type dementia and Lewy body dementia, focusing on the phenomenological data.

RESULTS

Very-late-onset schizophrenia-like psychosis appears to be a primary psychiatric diagnosis that is clinically distinct from PS, which emerges among established dementias, but remains a heterogeneous entity due to its age-based syndromic aspect. It is possible to differentiate between the more common phenotypes based on the aetiology of the dementia.

CONCLUSION

The results confirm the value of the phenomenological approach in terms of distinguishing between different aetiologies of PS among confirmed cases of dementias. Prospective longitudinal studies are required to examine the early discriminatory characteristics of PS in order to improve prognosis based on the nosographic framework thus established.

[Very late onset psychotic symptoms: psychosis or dementia? A phenomenological approach. A systematic review]

Very-late-onset psychotic symptoms (PS) are a common gateway to both neurodegenerative dementias and primary psychiatric disorders. Despite such similarities of clinical expression, there is no consensual guidelines or specific nosographic frame. The purpose of this systematic review was to establish a phenomenological classification of PS among the main neurodegenerative dementias and late-psychosis. It would allowed 1) the aknowledgement of etiology-specific psychotic phenotypes; 2) where appropriate, it would help the clinician to screen the psychiatric symptoms looking dementias; 3) it would justify the phenomenological research of very-late-onset PS among dementias at a pre-clinical cognitive stage to establish a nosographic frame of these PS based on the prognosis of dementia.

METHODS

A literature review was conducted searching for very-late-onset PS (>60 years old) in late-onset psychosis and among Alzheimer dementia type and Lewy bodies dementia, focusing on the phenomenological data.

RESULTS

The very-late-onset schizophrenia-like psychosis appears to be a primary psychiatric diagnosis clinically distinct from the PS emerging among established dementias, but remains a heterogeneous entity due to its age-based syndromic aspect. It has been possible to distinguish preferential phenotypes depending on the etiology of the dementia.

CONCLUSION

The results confirm the interest of the phenomenological approach to distinguish the etiology of the PS among confirmed dementias. Prospective longitudinal studies must examine the early discriminant characteristics of PS in order to enable a better prognostic prediction of the nosographic frame thereby established.

Genetic Heterogeneity of Alzheimer's Disease: Embracing Research Partnerships

Studies on the genetics of Alzheimer’s disease (AD) have revealed the complexity and heterogeneity of the disease. All our studies have supported this evidence and contribute to the current understanding of the genetic architecture of AD. This report reviews the success of our investigations, focusing on the implications and importance of the genetics of AD, and demonstrates the relevance of research strategies embracing partnerships.

The impact of depressive symptoms on health-related quality of life in patients with subjective cognitive decline, mild cognitive impairment, and Alzheimer's disease

BACKGROUND

Health-related quality of life (HRQOL) is an important issue in the context of dementia care. The purpose of this study was to investigate the association between HRQOL and depressive symptoms in patients with subjective cognitive decline (SCD) and subtypes of mild cognitive impairment (MCI) and Alzheimer´s disease (AD).

METHODS

In this cross-sectional, observational study, a control group and four experimental groups (SCD, non-amnestic MCI, amnesticMCI, AD) were compared. Neuropsychological measurers (NTBV) and psychological questionnaires were used for data collection.

RESULTS

The control group scored higher than patients with SCD, naMCI, aMCI, or AD for the Mental Health Component Score (MHCS) of the Short Form of the Health Survey (SF-36). The Physical Health Component Score (PHCS) of the SF-36 differed only between some groups. Furthermore, cognitive variables were more strongly associated with the physical aspects of HRQOL, whereas depressive symptoms were more strongly related with the mental aspects of HRQOL.

CONCLUSIONS

HRQOL and depressive symptoms are closely related in patients with cognitive impairments. Therefore, it is of great importance to assess patients with subjective impairment carefully in terms of depressive symptoms.

Neuroprotective effects of estrogens: the role of cholesterol

INTRODUCTION

Experimental and clinical evidence suggests that estrogens have protective effects in the brain. Nevertheless, their potential role against neurodegenerative diseases, in particular Alzheimer's disease (AD), is still a matter of debate. The identification of the seladin-1 gene (for SELective Alzheimer's Disease INdicator-1), which appeared to be significantly less expressed in brain region affected in AD, opened a new scenario in the field of neuroprotective mechanisms. Seladin-1 was found to have neuroprotective properties through its anti-apoptotic activity. In addition, it was subsequently demonstrated that seladin-1 also has enzymatic activity, because it catalyzes the conversion of desmosterol into cholesterol. Several studies have shown that an appropriate amount of membrane cholesterol plays a pivotal role to protect nerve cells against β-amyloid toxicity in AD and to counteract the synthesis of β-amyloid.

METHODS AND RESULTS

We demonstrated that the expression of seladin-1, as well as the synthesis of cell cholesterol, is stimulated by estrogens in human neuronal precursor cells. Cholesterol enriched cells became more resistant against oxidative stress and β-amyloid toxicity. We thus hypothesized that seladin-1 might be a mediator of the neuroprotective effects of estrogens. Indeed, in cells in which seladin-1 gene expression had been silenced by siRNA the protective effects of estrogens were lost. This finding indicates that seladin-1 is a crucial mediator of the neuroprotective effects of these hormones, at least in our cell model.

CONCLUSIONS

In summary, these results establish a new link between estrogens and cholesterol, which is represented by the neuroprotective factor seladin-1.

The green tea polyphenol (-)-epigallocatechin gallate prevents the aggregation of tau protein into toxic oligomers at substoichiometric ratios. FEBS Lett. 2015;589:77-83. [PMID: 25436420 DOI: 10.1016/j.febslet.2014.11.026]

The accumulation of amyloid-beta (Aβ) and tau aggregates is a pathological hallmark of Alzheimer's disease. Both polypeptides form fibrillar deposits, but several lines of evidence indicate that Aβ and tau form toxic oligomeric aggregation intermediates. Depleting such structures could thus be a powerful therapeutic strategy. We generated a fragment of tau (His-K18ΔK280) that forms stable, toxic, oligomeric tau aggregates in vitro. We show that (-)-epigallocatechin gallate (EGCG), a green tea polyphenol that was previously found to reduce Aβ aggregation, inhibits the aggregation of tau K18ΔK280 into toxic oligomers at ten- to hundred-fold substoichiometric concentrations, thereby rescuing toxicity in neuronal model cells.

In silico theoretical molecular modeling for Alzheimer's disease: the nicotine-curcumin paradigm in neuroprotection and neurotherapy

The aggregation of the amyloid-β-peptide (AβP) into well-ordered fibrils has been considered as the key pathological marker of Alzheimer‘s disease. Molecular attributes related to the specific binding interactions, covalently and non-covalently, of a library of compounds targeting of conformational scaffolds were computed employing static lattice atomistic simulations and array constructions. A combinatorial approach using isobolographic analysis was stochastically modeled employing Artificial Neural Networks and a Design of Experiments approach, namely an orthogonal Face-Centered Central Composite Design for small molecules, such as curcumin and glycosylated nornicotine exhibiting concentration-dependent behavior on modulating AβP aggregation and oligomerization. This work provides a mathematical and in silico approach that constitutes a new frontier in providing neuroscientists with a template for in vitro and in vivo experimentation. In future this could potentially allow neuroscientists to adopt this in silico approach for the development of novel therapeutic interventions in the neuroprotection and neurotherapy of Alzheimer‘s disease. In addition, the neuroprotective entities identified in this study may also be valuable in this regard.