Intrathecal corticosteroids might slow Alzheimer's disease progression

In Search for Low-Molecular-Weight Ligands of Human Serum Albumin That Affect Its Affinity for Monomeric Amyloid β Peptide

An imbalance between production and excretion of amyloid β peptide (Aβ) in the brain tissues of Alzheimer's disease (AD) patients leads to Aβ accumulation and the formation of noxious Aβ oligomers/plaques. A promising approach to AD prevention is the reduction of free Aβ levels by directed enhancement of Aβ binding to its natural depot, human serum albumin (HSA). We previously demonstrated the ability of specific low-molecular-weight ligands (LMWLs) in HSA to improve its affinity for Aβ. Here we develop this approach through a bioinformatic search for the clinically approved AD-related LMWLs in HSA, followed by classification of the candidates according to the predicted location of their binding sites on the HSA surface, ranking of the candidates, and selective experimental validation of their impact on HSA affinity for Aβ. The top 100 candidate LMWLs were classified into five clusters. The specific representatives of the different clusters exhibit dramatically different behavior, with 3- to 13-fold changes in equilibrium dissociation constants for the HSA-Aβ40 interaction: prednisone favors HSA-Aβ interaction, mefenamic acid shows the opposite effect, and levothyroxine exhibits bidirectional effects. Overall, the LMWLs in HSA chosen here provide a basis for drug repurposing for AD prevention, and for the search of medications promoting AD progression.

Types of memory, dementia, Alzheimer's disease, and their various pathological cascades as targets for potential pharmacological drugs

Alzheimer's disease (AD) is the most common type of dementia accounting for 90% of cases; however, frontotemporal dementia, vascular dementia, etc. prevails only in a minority of populations. The term dementia is defined as loss of memory which further takes several other categories of memories like working memory, spatial memory, fear memory, and long-term, and short-term memory into consideration. In this review, these memories have critically been elaborated based on context, duration, events, appearance, intensity, etc. The most important part and purpose of the review is the various pathological cascades as well as molecular levels of targets of AD, which have extracellular amyloid plaques and intracellular hyperphosphorylated tau protein as major disease hallmarks. There is another phenomenon that either leads to or arises from the above-mentioned hallmarks, such as oxidative stress, mitochondrial dysfunction, neuroinflammation, cholinergic dysfunction, and insulin resistance. Several potential drugs like antioxidants, anti-inflammatory drugs, acetylcholinesterase inhibitors, insulin mimetics or sensitizers, etc. studied in various previous preclinical or clinical reports were put as having the capacity to act on these pathological targets. Additionally, agents directly or indirectly targeting amyloid and tau were also discussed. This could be further investigated in future research.

Mining on Alzheimer's diseases related knowledge graph to identity potential AD-related semantic triples for drug repurposing

BACKGROUND

To date, there are no effective treatments for most neurodegenerative diseases. Knowledge graphs can provide comprehensive and semantic representation for heterogeneous data, and have been successfully leveraged in many biomedical applications including drug repurposing. Our objective is to construct a knowledge graph from literature to study the relations between Alzheimer's disease (AD) and chemicals, drugs and dietary supplements in order to identify opportunities to prevent or delay neurodegenerative progression. We collected biomedical annotations and extracted their relations using SemRep via SemMedDB. We used both a BERT-based classifier and rule-based methods during data preprocessing to exclude noise while preserving most AD-related semantic triples. The 1,672,110 filtered triples were used to train with knowledge graph completion algorithms (i.e., TransE, DistMult, and ComplEx) to predict candidates that might be helpful for AD treatment or prevention.

RESULTS

Among three knowledge graph completion models, TransE outperformed the other two (MR = 10.53, Hits@1 = 0.28). We leveraged the time-slicing technique to further evaluate the prediction results. We found supporting evidence for most highly ranked candidates predicted by our model which indicates that our approach can inform reliable new knowledge.

CONCLUSION

This paper shows that our graph mining model can predict reliable new relationships between AD and other entities (i.e., dietary supplements, chemicals, and drugs). The knowledge graph constructed can facilitate data-driven knowledge discoveries and the generation of novel hypotheses.

Deep phenotyping of Alzheimer's disease leveraging electronic medical records identifies sex-specific clinical associations

Alzheimer's Disease (AD) is a neurodegenerative disorder that is still not fully understood. Sex modifies AD vulnerability, but the reasons for this are largely unknown. We utilize two independent electronic medical record (EMR) systems across 44,288 patients to perform deep clinical phenotyping and network analysis to gain insight into clinical characteristics and sex-specific clinical associations in AD. Embeddings and network representation of patient diagnoses demonstrate greater comorbidity interactions in AD in comparison to matched controls. Enrichment analysis identifies multiple known and new diagnostic, medication, and lab result associations across the whole cohort and in a sex-stratified analysis. With this data-driven method of phenotyping, we can represent AD complexity and generate hypotheses of clinical factors that can be followed-up for further diagnostic and predictive analyses, mechanistic understanding, or drug repurposing and therapeutic approaches.

Framework of treating Alzheimer’s dementia

Current treatment paradigm in Alzheimer’s disease (AD) involves multiple approaches combining pharmacological and nonpharmacological intervention to mitigate the clinical symptoms, slow the progressive loss of cognitive and functional abilities, or modify the disease course. So far, beyond anti-cholinesterase inhibitors (AChEIs), donepezil, rivastigmine, galantamine, and antagonist of N-methyl-D-aspartic acid (NMDA) receptor, there are no newly approved medicines to treat AD. Under pharmacological treatment, the personal characteristic and the intra-individual therapeutic evaluations to examine various cognitive domains, behavioral and psychological problems, and global function should be considered when choosing any of AChEIs. The use of optimal dosage referring to the expected clinical outcomes and currently reported deficits from patient with AD has become an important issue in clinical treatment. Establishing and maintaining a strong therapeutic alliance to physician, patient, and caregiver is crucial and central to the comprehensive care in AD.

Can Disease-Modifying Anti-Rheumatic Drugs Reduce the Risk of Developing Dementia in Patients with Rheumatoid Arthritis?

Disease-modifying anti-rheumatic drugs (DMARDs) can reduce inflammation and slow progression of rheumatoid arthritis (RA). It remains unknown what impact DMARDs may have on dementia, where inflammation also plays a critical role in pathogenesis. Patients without a prior history of dementia who were newly diagnosed with RA between 2000 and 2005 were identified from Taiwan's National Health Insurance Research Database. The participants were stratified by age and gender. The outcome of interest was all-cause dementia, and Cox regression models were used to estimate the hazard ratio (HR) of dementia. The cumulative DMARD dosage was stratified by quartiles of defined daily doses. A total of 20,707 patients were diagnosed with RA, and 62,121 non-RA individuals aged 20 years or older were included. Cox proportional hazard regression analysis revealed that the RA cohort was 37% less likely to develop dementia compared with the non-RA cohort [adjusted HR 0.63, 95% confidence interval (CI) 0.55-0.72]. Further decreased risk was noted in DMARD users (adjusted HR 0.48, 95% CI 0.39-0.58) with dose-dependent effect. Subgroup analysis identified DMARD use as having a protective effect against developing dementia in female and younger patients. Also, in male and older patients, DMARD use further reduced the risk. These observations suggest that DMARDs may reduce the risk of developing dementia, and its effect is further increased at high cumulative dosages. These findings warrant further examination in randomized control trials.

Effect of the asthma-chronic obstructive pulmonary disease syndrome on the stroke, Parkinson's disease, and dementia: a national cohort study

Background

To evaluate the association of asthma–chronic obstructive pulmonary disease syndrome (ACOS) with neurodegenerative diseases (stroke, Parkinson's disease and dementia) and the role of the steroids in the neurodegenerative diseases among the ACOS cohort.

Materials and Methods

Comparison of the ACOS cohort (N = 10,260) with the non-ACOS cohort (n = 20,513) based on the patients aged ≧40 years in the National Health Insurance Research Database from January 1, 2000 to December 31, 2010. These patients follow up to diagnosis of neurodegenerative diseases or the December 31, 2011; using multivariable Cox proportional hazards models.

Results

After adjustment for potential confounders, the [adjusted hazard ratio (aHR), 95% confidence interval (CI)] in the ACOS cohort were [1.39, 1.28–1.50] [1.56, 1.34–1.81] and [1.43, 1.29–1.59] for stroke, Parkinson's disease, dementia; respectively. The [aHR, 95% CI] for ACOS cohort with (inhaler corticosteroids ≧0.13 gram/ oral steroids ≧0.08gram) were with less risk (all aHR<1, p values <0.05) for these 3 neurodegenerative diseases except Parkinson's disease with inhaler corticosteroids >0.43 gram. The risk of stroke and dementia were the lower in patients with < 250 μg/d of a fluticasone equivalent inhaler corticosteroids (aHR = 0.53, 95% CI = 0.35–0.79; aHR = 0.53, 95% CI = 0.31–0.90, respectively).

Conclusions

The ACOS cohort had a higher risk of the neurodegenerative diseases. The lower dose of the inhaler corticosteroids with cumulative dose ≧0.13 gram have the less risk of stroke and dementia.

Alzheimer's Disease: Exploring the Role of Inflammation and Implications for Treatment

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by both structural abnormalities and inflammation in the brain. While recent research has chiefly focused on the structural changes involved in AD, understanding the pathophysiology and associated inflammation of the AD brain helps to elucidate potential therapeutic and preventative options. By exploring the data supporting an inflammatory etiology of AD, we present a case for the use of existing evidence-based treatments addressing inflammation as promising options for treating and preventing AD. We present data demonstrating tumor necrosis factor alpha association with the inflammation of AD. We also discuss data supporting TNF alpha associated inflammation in traumatic brain injury, stroke, and spinal disc associated radiculopathy. We augment this previously unarticulated concept of a unifying pathophysiology of central nervous system disease, with reports of benefits of TNF alpha inhibition in many hundreds of patients with those diseases, including AD. We also assess the pathophysiologic and clinical trial evidence supporting the role of other inflammation resolving treatments in AD. In aggregate, the data from the several potentially effective therapeutic and preventative options contained within this report presents a clearer picture of next steps needed in research of treatment alternatives.

Significance of NF-κB as a pivotal therapeutic target in the neurodegenerative pathologies of Alzheimer's disease and multiple sclerosis

INTRODUCTION

Advances in molecular pathogenesis suggest that the chronic inflammation is a shared mechanism in the initiation and progression of multiple neurodegenerative diseases with diverse clinical manifestations such as Alzheimer's disease (AD) and Multiple sclerosis (MS). Restricted cell renewal and regenerative capacity make the neural tissues extremely vulnerable to the uncontrolled inflammatory process leading to irreversible tissue damage.

AREAS COVERED

A predominant consequence of increased inflammatory signaling is the upregulation of the transcription factor, NF-κB with subsequent neuroprotective or deleterious effects depending on the strength of the signal and the type of NF-κB dimers activated. We discuss the interplay between neuroinflammation and neurodegeneration keeping in focus NF-κB signaling as the point of convergence of multiple pathways associated with the development of the neurodegenerative pathologies, AD and MS.

EXPERT OPINION

Considerable interest exists in developing efficient NF-κB inhibitors for neurodegenerative diseases. The review includes an overview of natural compounds and rationally designed agents that inhibit NF-κB and mediate neuroprotection in AD and MS. The key chemical moieties of the natural and the synthetic compounds provide efficient leads for the development of effective small molecule inhibitors that selectively target NF-κB activation; this would result in the desired benefit to risk therapeutic effects.

Up-regulation of P-glycoprotein reduces intracellular accumulation of beta amyloid: investigation of P-glycoprotein as a novel therapeutic target for Alzheimer's disease

OBJECTIVES

Several studies have suggested the efflux transporter P-glycoprotein (P-gp) to play a role in the etiology of Alzheimer's disease through the clearance of amyloid beta (Aβ) from the brain. In this study, we aimed to investigate the possibility of P-gp as a potential therapeutic target for Alzheimer's disease by examining the impact of P-gp up-regulation on the clearance of Aβ, a neuropathological hallmark of Alzheimer's disease.

METHODS

Uptake studies for ¹²⁵I-radiolabelled Aβ₁₋₄₀, and fluorescent immunostaining technique for P-gp and fluorescent imaging of Aβ₁₋₄₀ were carried out in LS-180 cells following treatment with drugs known to induce P-gp expression.

KEY FINDINGS

Approximately 10-35% decrease in ¹²⁵I-Aβ₁₋₄₀ intracellular accumulation was observed in cells treated with rifampicin, dexamethasone, caffeine, verapamil, hyperforin, β-estradiol and pentylenetetrazole compared with control. Also, fluorescent micrographs showed an inverse relationship between levels of P-gp expression and 5-carboxyfluorescein labelled Aβ (FAM-Aβ₁₋₄₀) intracellular accumulation. Quantitative analysis of the micrographs revealed that the results were consistent with those of the uptake studies using ¹²⁵I-Aβ₁₋₄₀.

CONCLUSIONS

The investigated drugs were able to improve the efflux of Aβ₁₋₄₀ from the cells via P-gp up-regulation compared with control. Our results elucidate the importance of targeting Aβ clearance via P-gp up-regulation, which will be effective in slowing or halting the progression of Alzheimer's disease.