Acupuncture Therapy on Dementia: Explained with an Integrated Analysis on Therapeutic Targets and Associated Mechanisms

Transcriptomic and network analysis identifies shared pathways across Alzheimer's disease and vascular dementia

Alzheimer's disease (AD) and vascular dementia (VaD) are often accompanied, but there are no effective differential diagnosis and treatment for VaD. The search for common pathogenic targets or pathways connecting the two diseases is helpful to the drug development and treatment of the disease. In this study, we used gene expression array data from the GEO database to analyze common differentially expressed genes (DEGs) in the temporal cortex of patients with AD and VaD. AD and VaD shared 143 DEGs. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis showed that the biological function of common DEGs was mainly related to chemical synaptic transmission, neuroactive ligand-receptor, and cytokine-cytokine receptor interaction pathway. The protein-protein interaction (PPI) analysis showed the interaction of down- and up-regulated DEGs. The mRNA expression levels of key proteins in neuroactive ligand-receptor and cytokine-cytokine receptor interaction pathway were verified in AD and VaD mice. The real-time quantitative polymerase chain reaction (RT-qPCR) test was used to detect the expression of DEGs. Data of RT-qPCR showed the mRNA level of γ-aminobutyric acid type B receptor subunit 1 (GABBR1) was decreased in both AD and VaD. In addition, the mRNA of interleukin-17 receptor A (IL-17RA), IL-17 and IL-18 were increased. In conclusion, the shared genes in AD and VaD were verified in our study. We identified the critical genes to offer a theoretical basis for understanding the linkage of AD and VaD, which provided potential drug targets against AD and VaD.

Substantia nigra and blood gene signatures and biomarkers for Parkinson's disease from integrated multicenter microarray-based transcriptomic analyses

Background

Parkinson's disease (PD) is a complex, common neurodegenerative disorder with unclear etiology. The pathogenic hallmark is the death of dopaminergic neurons in the substantia nigra. PD diagnosis depends on clinical manifestation of symptoms but is lack of effective biomarker.

Methods

Available human microarray-based transcriptomic datasets of the substantia nigra and blood were acquired for PD cases and controls. Robust rank aggregation and Weighted Gene Co-expression Network analysis were performed to identify gene signatures in substantia nigra and blood of PD. An overlapping analysis and validation in an independent cohort were followed to identify PD blood biomarkers.

Results

Eight datasets of substantia nigra and 3 datasets of blood were retrieved, which comprised 150 substantia nigra and 571 blood samples. Integrated differentially expressed genes (DEG) and module analyses showed that the substantia nigra gene signature in PD comprised 170 key genes, mainly involved in dopaminergic synapse, neuroactive ligand-receptor interaction, calcium signaling pathway, and Parkinson disease. The blood gene signature had only 65 DEGs, but with no robust co-expression module identified. Two genes, LRRN3 and TUBB2A, were both downregulated in the substantia nigra and blood of PD. But only TUBB2A was validated in the blood of independent cohort and showed a capacity of PD prediction.

Conclusion

The present study identified PD-associated gene signatures of the substantia nigra and blood, and demonstrated that the reduced expression of TUBB2A in the blood is promising to predict PD. Our findings provide novel insight into the mechanisms underlying PD pathophysiology and the development of PD biomarkers.

Bioinformatic Identification of Signaling Pathways and Hub Genes in Vascular Dementia

BACKGROUND

Vascular dementia (VaD) is a prevalent neurodegenerative disease characterized by cognitive impairment due to cerebrovascular factors, affecting a significant portion of the aging population and highlighting the critical need to understand specific targets and mechanisms for effective prevention and treatment strategies. We aimed to identify pathways and crucial genes involved in the progression of VaD through bioinformatics analysis and subsequently validate these findings.

METHODS

We conducted differential expression analysis, Weighted Gene Co-expression Network Analysis (WGCNA), Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, and Protein-Protein Interaction (PPI) analysis. We utilized pheochromocytoma 12 (PC12) cells to create an in vitro oxygen-glucose deprivation (OGD) model. We investigated the impact of overexpression and interference of adrenoceptor alpha 1D (ADRA1D) on OGD PC12 cells using TdT-mediated dUTP nick-end labeling (TUNEL), reverse transcription-quantitative polymerase chain reaction (RT-qPCR), western blot (WB), and Fluo-3-pentaacetoxymethyl ester (Fluo-3 AM) analysis.

RESULTS

We found 187 differentially expressed genes (DEGs) in the red module that were strongly associated with VaD and were primarily enriched in vasoconstriction, G protein-coupled amine receptor activity, and neuroactive ligand-receptor interaction, mitogen-activated protein kinase (MAPK) signaling pathway, and cell adhesion. Among these pathways, we identified ADRA1D as a gene shared by vasoconstriction, G protein-coupled amine receptor activity, and neuroactive ligand-receptor interaction. The TUNEL assay revealed a significant decrease in PC12 cell apoptosis with ADRA1D overexpression (p < 0.01) and a significant increase in apoptosis upon silencing ADRA1D (p < 0.01). RT-qPCR and WB analysis revealed elevated ADRA1D expression (p < 0.001) and decreased phospholipase C beta (PLCβ) and inositol 1,4,5-trisphosphate receptor (IP3R) expression (p < 0.05) with ADRA1D overexpression. Moreover, the Fluo-3 AM assessment indicated significantly lower intracellular Ca2+ levels with ADRA1D overexpression (p < 0.001). Conversely, interference with ADRA1D yielded opposite results.

CONCLUSION

Our study provides a new perspective on the pathogenic mechanisms of VaD and potential avenues for therapeutic intervention. The results highlight the role of ADRA1D in modulating cellular responses to OGD and VaD, suggesting its potential as a target for VaD treatment.