AUTHOR=Xu Jing , Li Jia , Sun Ya-juan , Quan Wei , Liu Li , Zhang Qing-hui , Qin Yi-dan , Pei Xiao-chen , Su Hang , Chen Jia-jun 

TITLE=Identification of key genes and signaling pathways associated with dementia with Lewy bodies and Parkinson's disease dementia using bioinformatics

JOURNAL=Frontiers in Neurology

VOLUME=Volume 14 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2023.1029370

DOI=10.3389/fneur.2023.1029370

ISSN=1664-2295

ABSTRACT=Abstract
Objective: Dementia with Lewy bodies (DLB) and Parkinson’s disease dementia (PDD) are collectively known as Lewy body dementias (LBD). Considering the heterogeneous nature of LBD and the different constellations of symptoms with which patients can present, the exact molecular mechanism underlying the differences between these two isoforms is still unknown. Therefore, the study aimed to explore the biomarkers and potential mechanisms that distinguish between PDD and DLB.
Methods: The mRNA expression profile dataset of GSE150696 were acquired from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) between 12 DLB and 12 PDD were identified from Brodmann area 9 of human postmortem brains using GEO2R. A series of bioinformatics methods were applied to identify the potential signaling pathways involved, and a protein-protein interaction (PPI) network was constructed. Weighted gene co-expression network analysis (WGCNA) was used to further investigate the relationship between gene co-expression and different LBD subtypes. Hub genes that are strongly associated with PDD and DLB were obtained from the intersection of DEGs and selected modules by WGCNA. 
Results: 1864 DEGs between PDD and DLB were filtered by the online analysis tool GEO2R. We found that the most significant GO and KEGG enriched terms are involved in the establishment of the vesicle localization and pathways of neurodegeneration-multiple diseases. Glycerolipid metabolism and viral myocarditis were enriched in the PDD group. A B-cell receptor signaling pathway and one carbon pool by folate correlated with DLB in the results obtained from the GSEA. We found several clusters of co-expressed genes which we designated by colors in our WGCNA analysis. Furthermore, we identified seven up-regulated genes SNAP25, GRIN2A, GABRG2, GABRA1, GRIA1, SLC17A6 and SYN1 which are significantly correlated with PDD.