Current Alzheimer research最新文献

Alzheimer's disease (AD) and vascular dementia (VD) are the leading causes of dementia, presenting a significant challenge in differential diagnosis. While their clinical presentations can overlap, their underlying pathologies are distinct. AD is characterized by the accumulation of amyloid plaques and neurofibrillary tangles, leading to progressive neurodegeneration. VD, on the other hand, arises from cerebrovascular insults that disrupt blood flow to the brain, causing neuronal injury and cognitive decline. Despite distinct etiologies, AD and VD share common risk factors such as hypertension, diabetes, and hyperlipidemia. Recent research suggests a potential role for oral microbiota in both diseases, warranting further investigation. The diagnostic dilemma lies in the significant overlap of symptoms including memory loss, executive dysfunction, and personality changes. The absence of definitive biomarkers and limitations of current neuroimaging techniques necessitate a multi-modal approach integrating clinical history, cognitive assessment, and neuroimaging findings. Promising avenues for improved diagnosis include the exploration of novel biomarkers like inflammatory markers, MMPs, and circulating microRNAs. Additionally, advanced neuroimaging techniques hold promise in differentiating AD and VD by revealing characteristic cerebrovascular disease patterns and brain atrophy specific to each condition. By elucidating the complexities underlying AD and VD, we can refine diagnostic accuracy and optimize treatment strategies for this ever-growing patient population. Future research efforts should focus on identifying disease-specific biomarkers and developing more effective neuroimaging methods to achieve a definitive diagnosis and guide the development of targeted therapies.

Introduction: Alzheimer's disease (AD) is an alarmingly prevalent worldwide neurological disorder that affects millions of people and has severe effects on cognitive functions. The amyloid hypothesis, which links AD to Aβ (amyloid beta) plaque aggregation, is a well-acknowledged theory. The β-secretase (BACE1) is the main cause of Aβ production, which makes it a possible target for therapy. FDA-approved therapies for AD do exist, but none of them explicitly target BACE1, and their effectiveness is constrained and accompanied by adverse effects.

Materials and methods: We determined the essential chemical components of medicinal herbs by conducting a thorough literature research for BACE1. Computational methods like molecular docking, ADMET (Absorption, distribution, metabolism, excretion, toxicity) screening, molecular dynamic simulations, and MMPBSA analysis were performed in order to identify the most promising ligands for β-secretase.

Results: The results suggested that withasomniferol, tinosporide, and curcumin had better binding affinity with BACE1, suggesting their potential as therapeutic candidates against Alzheimer's disease.

Conclusion: Herbal therapeutics have immense applications in the treatment of chronic diseases like Alzheimer's disease, and there is an urgent need to assess their efficacy as therapeutics.

Background: Alzheimer's Disease (AD) is a long-term brain disorder that worsens over time. A cholinesterase inhibitor called Donepezil HCl (DNZ) is used to treat and control AD. Due to its failure to reach the appropriate concentration in the brain cells, its efficacy upon oral administration is limited, and thus investigation of alternative administration route is necessary.

Objective: The objective of this study was to develop donepezil HCl-loaded Nanostructured Lipid Carriers (NLCs) that can bypass the blood-brain barrier and thus be directly delivered to the brain through the nasal route. This method improves availability at the site of action, reduces the negative effects of oral medication, and ensures an expedited commencement of action.

Method: High-pressure homogenization and ultrasonication were used to formulate NLCs. Glyceryl Monostearate (GMS) as a solid lipid, Tween 80 as a surfactant, and Poloxamer 407 as a co-- surfactant were used. In this study, argan oil was employed as a liquid lipid as well as a penetration enhancer.

Results: The chosen NLCs displayed a particle size of 137.34 ± 0.79 nm, a PDI of 0.365 ± 0.03, and a zeta potential of -10.4 mV. The selected formulation showed an entrapment efficiency of 84.05 ± 1.30% and a drug content of 77.02 ± 0.23%. The concentration of the drug in the brain after intravenous and intranasal administration of DNZ NLCs at 1 h was found to be 0.490 ± 0.007 and 4.287 ± 0.115, respectively. Thus, the concentration of DNZ achieved in the brain after intranasal administration of DNZ NLCs was approximately 9 times more than the concentration when administered by intravenous route.

Conclusion: The DNZ-loaded NLCs, when administered via nasal route, showed markedly improved drug availability in the brain, suggesting an efficient drug delivery strategy to treat Alzheimer's disease.

Objective: Alzheimer's disease, a progressive neurodegenerative disorder, severely impacts cognitive function and daily living. The current treatment provides only symptomatic relief, and thus, disease-modifying therapies targeting underlying causes are needed. Although several potential therapies are in various stages of clinical trials, bringing a new Alzheimer's drug to market remains challenging. Hence, researchers are also exploring monoclonal antibodies, tau protein inhibitors, and anti-inflammatory drugs as treatment options. Conventionally designed dosage forms come with limitations like poor absorption, first-pass metabolism, and low bioavailability. They also cause systemic adverse effects because these designed systems do not provide target- specific drug delivery. Thus, in this review, the authors highlighted the current advancements in the development of intranasal nanoformulations for the treatment of Alzheimer's disease. This strategy of delivering anti-Alzheimer drugs through the nasal route may help to target the drug exactly to the brain, achieve rapid onset of action, avoid first-pass metabolism, and reduce the side effects and dose required for administration.

Conclusion: Delivering drugs to the brain through the nasal route for treating Alzheimer's disease is crucial due to the limited efficacy of existing treatments and the profound impact of the disease on patients and their families. Thus, by exploring innovative approaches such as nose-to-brain drug delivery, it is possible to improve the quality of life for individuals living with Alzheimer's and alleviate its societal burden.

Alzheimer's disease (AD) is the frequent form of dementia in the world. Despite over 100 years of research into the causes of AD, including amyloid and tau protein, the research has stalled and has not led to any conclusions. Moreover, numerous projects aimed at finding a cure for AD have also failed to achieve a breakthrough. Thus, the failure of anti-amyloid and anti-tau protein therapy to treat AD significantly influenced the way we began to think about the etiology of the disease. This situation prompted a group of researchers to focus on ischemic brain episodes, which, like AD, mostly present alterations in the hippocampus. In this context, it has been proposed that cerebral ischemic incidents may play a major role in promoting amyloid and tau protein in neurodegeneration in AD. In this review, we summarized the experimental and clinical research conducted over several years on the role of ischemic brain episodes in the development of AD. Studies have shown changes typical of AD in the course of brain neurodegeneration post-ischemia, i.e., progressive brain and hippocampal atrophy, increased amyloid production, and modification of tau protein. In the post-ischemic brain, the diffuse and senile amyloid plaques and the development of neurofibrillary tangles characteristic of AD were revealed. The above data evidently showed that after brain ischemia, there are modifications in protein folding, leading to massive neuronal death and damage to the neuronal network, which triggers dementia with the AD phenotype.

Alzheimer's disease (AD) is the most common type of dementia among middle-aged and elderly individuals. Accelerating the prevention and treatment of AD has become an urgent problem. New technology including Computer-aided drug design (CADD) can effectively reduce the medication cost for patients with AD, reduce the cost of living, and improve the quality of life of patients, providing new ideas for treating AD. This paper reviews the pathogenesis of AD, the latest developments in CADD and other small-molecule docking technologies for drug discovery and development; the current research status of small-molecule compounds for AD at home and abroad from the perspective of drug action targets; the future of AD drug development.

Background: Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder, with a significant burden on global health. AD is characterized by a progressive cognitive decline and memory loss. Emerging research suggests a potential link between periodontitis, specifically the presence of oral bacteria such as Porphyromonas gingivalis (P. gingivalis), and AD progression. P. gingivalis produces an enzyme, Agmatine deiminase (AgD), which converts agmatine to N-carbamoyl putrescine (NCP), serving as a precursor to essential polyamines. Recent studies have confirmed the correlation between disruptions in polyamine metabolism and cognitive impairment.

Objective: This study aims to investigate the dysregulation of P. gingivalis Agmatine deiminase (PgAgD) in the context of AD.

Methods: Saliva samples were collected from a total of 54 individuals, including 27 AD patients and 27 healthy controls. The expression of the PgAgD gene was analyzed using quantitative Real-- Time PCR.

Results: The results showed a significant decrease in PgAgD gene expression in the saliva samples of AD patients compared to healthy controls. This downregulation was found in AD patients with advanced stages of periodontitis. Additionally, a correlation was observed between the decrease in PgAgD expression and the 30-item Mini-Mental State Examination (MMSE) score.

Conclusion: These findings suggest that measuring PgAgD expression in saliva could be a noninvasive tool for monitoring AD progression and aid in the early diagnosis of patients with periodontitis. Further research is needed to validate our results and explore the underlying mechanisms linking periodontitis, PgAgD expression, and AD pathophysiology.

Background: Neurodegenerative disorders like Alzheimer's disease (AD) involve the abnormal aggregation of tau protein, which forms toxic oligomers and amyloid deposits. The structure of tau protein is influenced by the conformational states of distinct proline residues, which are regulated by peptidyl-prolyl isomerases (PPIases). However, there has been no research on the impact of human cyclophilin A (CypA) as a PPIase on (non-phosphorylated) tau protein aggregation.

Methods: On the basis of these explanations, we used various spectroscopic techniques to explore the effects of CypA on tau protein aggregation behavior.

Results: We demonstrated the role of the isomerization activity of CypA in promoting the formation of tau protein amyloid fibrils with well-defined and highly ordered cross-β structures. According to the "cistauosis hypothesis," CypA's ability to enhance tau protein fibril formation in AD is attributed to the isomerization of specific proline residues from the trans to cis configuration. To corroborate this theory, we conducted refolding experiments using lysozyme as a model protein. The presence of CypA increased lysozyme aggregation and impeded its refolding process. It is known that proper refolding of lysozyme relies on the correct (trans) isomerization of two critical proline residues.

Conclusion: Thus, our findings confirmed that CypA induces the trans-to-cis isomerization of specific proline residues, ultimately leading to increased aggregation. Overall, this study highlights the emerging role of isomerization in tau protein pathogenesis in AD.

Introduction: The Corpus Callosum (CC) is the largest commissural tract in the nervous system. Few studies have examined the extent of CC in Alzheimer's disease (AD) patients, and these studies have reported conflicting findings.

Materials and methods: The study was performed using 176 brain MRI images of 88 Alzheimer's patients (55 women-32 men) and 88 healthy individuals (44 women-44 men).

Results: In our study, 7 different parameters of the CC were measured, and their average values were determined. We measured each parameter separately in AD patients and healthy individuals and compared them with each other.

Conclusion: CC has an important place not only in Patients with AD but also in other neurodegenerative diseases. We consider that our study will be useful in the evaluation of Patients with AD.