Vol 21, No 6 (2024)
- Year: 2024
- Articles: 6
- URL: https://vietnamjournal.ru/1567-2050/issue/view/9946
Medicine
Correlations between Cerebrospinal Fluid Biomarkers and Gray Matter Atrophy in Alzheimer's and Behavioural Variant Frontotemporal Dementia
Abstract
Introduction:Distinguishing between frontotemporal dementia (FTD) and Alzheimers disease (AD) in their early stages remains a significant clinical challenge. Cerebrospinal fluid (CSF) biomarkers (total Tau, phosphorylated Tau, and beta-amyloid) are promising candidates for identifying early differences between these conditions. This study investigates the relationship between grey matter density and CSF markers in the behavioural variant of frontotemporal dementia (bvFTD) and Alzheimers disease (AD).
Method:CSF and 3D T1-weighted magnetic resonance (MR) images were acquired from 14 bvFTD patients, 15 AD patients, and 13 cognitively normal (CN) matched subjects. The CSF markers and their relative ratios (total Tau/beta-amyloid, phosphorylated Tau/beta-amyloid) were compared across the three groups. Voxel-based morphometry (VBM) was performed to characterize the anatomical changes in bvFTD and AD patients compared to CN subjects. Grey matter density maps were obtained by automatic segmentation of 3.0 Tesla 3D T1-Weighted MR Images, and their correlation with CSF markers and relative ratios was investigated.
Results:Results demonstrated that, as compared to CN subjects, AD patients are characterised by higher CSF total Tau levels and lower beta-amyloid levels; however, beta-amyloid and relative ratios discriminated AD from bvFTD. In addition, AD and bvFTD patients showed different patterns of atrophy, with AD exhibiting more central (temporal areas) and bvFTD more anterior (frontal areas) atrophy. A correlation was found between grey matter density maps and CSF marker concentrations in the AD group, with total Tau and phosphorylated Tau levels showing a high association with low grey matter density in the left superior temporal gyrus.
Conclusion:Overall, while bvFTD lacks a CSF marker profile, CSF beta-amyloid levels are useful for differentiating AD from bvFTD. Furthermore, MR structural imaging can contribute significantly to distinguishing between the two pathologies.



Analysis of Alzheimer's Disease-Related Mortality Rates Among the Elderly Populations Across the United States: An Analysis of Demographic and Regional Disparities from 1999 to 2020
Abstract
Introduction:Alzheimers Disease (AD) is the leading cause of dementia and a significant public health concern, characterized by high incidence, mortality, and economic burden. This study analyzes the mortality patterns and demographic disparities in Alzheimer's disease-related deaths among the elderly population in the United States from 1999 through 2020.
Methods:Alzheimer's disease mortality data for individuals 65 and older were obtained from the CDC WONDER database, utilizing ICD-10 codes G30.0, G30.1, G30.8, and G30.9 for identification. Demographic and regional variables included age, gender, race/ethnicity, place of death, urban- rural status, and geographic region. Crude death rates (CR) and age-adjusted mortality rates (AAMR) per 100,000 individuals were calculated. Joinpoint Regression Program 5.0.2 was used to analyze trends, calculating Annual Percentage Changes (APCs) and Average Annual Percentage Changes (AAPCs).
Results:From 1999 to 2020, 1,852,432 deaths were attributed to AD among individuals aged 65 and older. The AAMR increased from 128.8 in 1999 to 254.3 in 2020, with an AAPC of 2.99% (95% CI = 2.61-3.48). The age-adjusted mortality rate (AAMR) was higher in females (218.5) than in males (163.5). Among racial and ethnic groups, non-Hispanic whites had the highest AAMR, followed by Non-Hispanic Blacks and Hispanics. Regionally, the West reported the highest AAMR, while the Northeast recorded the lowest. Most deaths occurred in nursing homes (57.3%), with a significant portion also occurring at decedents' homes (22.4%).
Conclusion:AD mortality rates in the U.S. have risen significantly, with notable disparities across age, gender, race, and geographic regions. These findings highlight the need for targeted interventions and research to address the growing burden of AD, particularly among the most affected demographic groups.



Molecular Mechanisms of GFAP and PTPRC in Alzheimer's Disease: An Analysis of Neuroinflammatory Response and Progression
Abstract
Introduction:Alzheimer's disease (AD) is a complex neurological disorder that progressively worsens. Although its exact causes are not fully understood, new research indicates that genes related to non-neuronal cells change significantly with age, playing key roles in AD's pathology. METHOD: This study focuses on a protein network centered on Glial Fibrillary Acidic Protein (GFAP) and Protein Tyrosine Phosphatase Receptor Type C (PTPRC).
Method:This study focuses on a protein network centered on Glial Fibrillary Acidic Protein (GFAP) and Protein Tyrosine Phosphatase Receptor Type C (PTPRC).
The Key Findings of this Study Include:1. A significant correlation was observed between GFAP and PTPRC expression throughout AD progression, which links closely with clinical phenotypes and suggests their role in AD pathology. 2. A molecular network centered on GFAP and PTPRC, including Catenin Beta 1 (CTNNB1) and Integrin Beta 2 (ITGB2), showed distinct changes in interactions, highlighting its regulatory role in AD. 3. Analysis of GSE5281 data revealed a decline in the interaction strength within this network, pointing to potential desynchronization as a biomarker for AD. 4. SVM diagnostic models comparing GFAP expression and coupling values confirmed this desynchronization, suggesting it worsens with AD progression.
Result:Based on these findings, it is hypothesized that as AD progresses, the GFAP- and PTPRCcentered molecular framework undergoes significant changes affecting key biological pathways. These changes disrupt immune regulation and cellular functions, increasing immune cell activation and inflammation in the brain. This may impair neuronal communication and synaptic functionality, exacerbating AD's pathology.
Conclusion:To verify these findings, Support Vector Machine (SVM) diagnostic models and correlation analyses were used to examine changes in this network, indicating that its dysregulation significantly affects AD progression.



Age-Related Differences in the Association between Lifes Essential 8 and Cognition in Cognitively Normal Adults: The CABLE Study
Abstract
Background:This study investigated the relationship between Life's Essential 8 (LE8), a recently updated lifestyle-related health factor, and cognition across multiple life stages.
Methods:We enrolled 1098 cognitively normal participants from the Chinese Alzheimer's Biomarker and Lifestyle (CABLE) study. We investigated the interactions between age and LE8 on cognition. Multiple linear regression models were utilized to explore the relationship between the LE8 total scores and its two subscales scores with cognition in the total sample, as well as in the mid-age (≤65 years) and the late-age (>65 years) subgroups. In addition, mediation analyses were performed to explore the biologically plausible pathways between LE8 and cognition.
Results:There was a significant interaction effect between age and LE8 total scores on MOCA score (P = 0.030). The mid-age subgroup showed a positive correlation between LE8 total scores and CM-MMSE (β = 0.110, P = 0.005) and MOCA (β = 0.112, P = 0.005) scores. However, no significant associations were found in the late-age subgroup. In the mid-age subgroup, CSF p-tau partially mediated the relationship between LE8 total scores and its two subscales and cognition, with a mediation proportion ranging from 6% to 12%.
Conclusion:Our findings revealed that the association of the LE8 total scores with MOCA and CM-MMSE scores were significant in mid-age adults rather than late-age adults, indicating that the association might be age-specific and emphasizing the importance of lifestyle interventions in mid-life.



Associations between Physical Performance Tests with Cognitive Changes: The Moderating Effect of Cognitive Status
Abstract
Introduction/Objective:Age-related cognitive decline has been linked with risk factors, including physical performance. Prior studies investigating such associations were typically conducted in clinical settings within Western populations with a frequent focus on late neurocognitive diagnostic stages (i.e., Alzheimers disease), reducing their generalizability to the Asian population and early neurocognitive stages. To address these knowledge gaps, our study investigated longitudinal associations between physical performance measures at baseline and cognitive change in global cognition, executive functioning (EF) based and non-executive functioning (non- EF) based cognitive domains within the Singaporean population. The moderating role of early neurocognitive status, namely mild cognitive impairment (MCI) and cognitively normal (CN), was also examined.
Methods:This paper examined data from 347 participants (CN = 284; MCI = 63) who participated in the Community Health and Intergenerational (CHI) study at baseline and follow-up. Data from a neurocognitive battery and three physical performance tests, namely the timed-up and go (TUG), fast gait speed (FGS) and 30-second chair-stand test (30s-CST), were analysed using multivariate linear regression models.
Results:Only one significant association between FGS scores and cognitive change in Semantic Fluency was observed; other associations were not significant. Cognitive status also significantly moderated associations between TUG/30s-CST tasks with several neurocognitive tests.
Conclusion:The lack of significant longitudinal associations between baseline physical performance measures and cognitive change differed from findings in the literature. Nevertheless, the moderating role of cognitive status further highlighted the need to account for cognitive status when exploring such associations within a heterogeneous group of older adults without dementia.



Identifying the Role of Oligodendrocyte Genes in the Diagnosis of Alzheimer's Disease through Machine Learning and Bioinformatics Analysis
Abstract
Background:Due to the heterogeneity of Alzheimer's disease (AD), the underlying pathogenic mechanisms have not been fully elucidated. Oligodendrocyte (OL) damage and myelin degeneration are prevalent features of AD pathology. When oligodendrocytes are subjected to amyloid-beta (Aβ) toxicity, this damage compromises the structural integrity of myelin and results in a reduction of myelin-associated proteins. Consequently, the impairment of myelin integrity leads to a slowdown or cessation of nerve signal transmission, ultimately contributing to cognitive dysfunction and the progression of AD. Consequently, elucidating the relationship between oligodendrocytes and AD from the perspective of oligodendrocytes is instrumental in advancing our understanding of the pathogenesis of AD.
Objective:Here, an attempt is made in this study to identify oligodendrocyte-related biomarkers of AD.
Methods:AD datasets were obtained from the Gene Expression Omnibus database and used for consensus clustering to identify subclasses. Hub genes were identified through differentially expressed genes (DEGs) analysis and oligodendrocyte gene set enrichment. Immune infiltration analysis was conducted using the CIBERSORT method. Signature genes were identified using machine learning algorithms and logistic regression. A diagnostic nomogram for predicting AD was developed and validated using external datasets and an AD model. A small molecular compound was identified using the eXtreme Sum algorithm.
Results:46 genes were found to be significantly correlated with AD progression by examining the overlap between DEGs and oligodendrocyte genes. Two subclasses of AD, Cluster A, and Cluster B, were identified, and 9 signature genes were identified using a machine learning algorithm to construct a nomogram. Enrichment analysis showed that 9 genes are involved in apoptosis and neuronal development. Immune infiltration analysis found differences in immune cell presence between AD patients and controls. External datasets and RT-qPCR verification showed variation in signature genes between AD patients and controls. Five small molecular compounds were predicted.
Conclusion:It was found that 9 oligodendrocyte genes can be used to create a diagnostic tool for AD, which could help in developing new treatments.


