Network based approaches reveal cell subtype specific roles of astrocytes and oligodendrocytes during alzheimer’s disease

2022-10
Ilgun, Atilay
Cakir, Tunahan
NETWORK BASED APPROACHES REVEAL CELL SUBTYPE SPECIFIC ROLES OF ASTROCYTES AND OLIGODENDROCYTES DURING ALZHEIMER’S DISEASE Atilay Ilgun1, Tunahan Cakir1 1 Department of Bioengineering, Gebze Technical University 41400, Gebze/KOCAELI e-mail: atilay.ilgun2016@gtu.edu.tr Although, Alzheimer’s disease seems to be neuron-based-disorder, contribution of glial cells to AD pathology is undeniable [1,2]. Investigation of transcriptomic changes on glial cells during AD is important since glial cells have many functions like synapse organization, BBB maintenance. Further investigations based on single-nuclei RNA-seq studies have revealed that astrocytes and oligodendrocytes have certain cell-subtypes, and those cell-subtypes have different expression profiles during AD [3]. In our study, protein-protein-interaction (PPI) networks were used to infer neuroprotective/neurotoxic impacts of the gene expression changes observed in astrocyte and oligodendrocyte cell subtypes during AD by using a snRNA-seq dataset that became recently available [3]. Its major difference from other snRNA-seq studies in literature for AD is the enrichment of astrocyte cells, leading to about 10-fold more captured astrocytic nuclei per donor in the dataset. KeyPathwayMiner was used to map each subtype of the cell types on PPI network, leading to identification of subnetworks enriched with differentially expressed genes [4]. Comparative analysis of the subnetworks revealed functional roles of the individual astrocyte and oligodendrocyte cell-subtypes. Detection of cell-subtypes in bulk transcriptome data by using deconvolution algorithms is another focus of our study. Deconvolution algorithms can predict cell-type specific expression values from bulk transcriptome datasets. Using MIND [5] algorithm, a comprehensive bulk AD transcriptomic dataset [6] covering 403 patients and 164 control samples was processed to predict cell type-specific expressions in the dataset, which was further subjected to clustering algorithms to predict subtypes in the cell types. PPI based subnetwork identification was also applied to those cell types. Characterization of single-cell based and deconvolution-based cell-subtype specific subnetworks through functional enrichment analysis shows that improved deconvolution algorithms are needed to better capture molecular alterations in cell types in response to AD. This study was financially supported through a grant by TUBITAK (Project Code: 120S824).

Suggestions

Systems-level analysis reveals multiple modulators of epithelial-mesenchymal transition and identifies DNAJB4 and CD81 as novel metastasis inducers in breast cancer
Kagiali, Zeynep Cansu Üretmen; Sanal, Erdem; Karayel, Özge; Polat, Ayşe Nur; Saatçi, Özge; Ersan, Pelin Gülizar; Trappe, Kathrin; Renard, Bernhard Y.; Önder, Tamer T.; Tunçbağ, Nurcan; Şahin, Özgür; Özlü, Nurhan (American Society for Biochemistry & Molecular Biology (ASBMB), 2019-09)
Epithelial-mesenchymal transition (EMT) is driven by complex signaling events that induce dramatic biochemical and morphological changes whereby epithelial cells are converted into cancer cells. However, the underlying molecular mechanisms remain elusive. Here, we used mass spectrometry based quantitative proteomics approach to systematically analyze the post-translational biochemical changes that drive differentiation of human mammary epithelial (HMLE) cells into mesenchymal. We identified 314 proteins out...
Meta analysis of alzheimer’s disease at the gene expression level
İzgi, Hamit; Somel, Mehmet; Department of Biology (2017)
In this study, publicly available microarray gene expression datasets are used to investigate common gene expression changes in different postmortem brain regions in Alzheimer’s Disease (AD) patients compared to control subjects, and to find possible functional associations related to these changes. The hypothesis is that pathogenesis of the disease converges into common patterns of dysregulation/alteration or dysfunction in molecular pathways across different brain regions in AD. In total, I studied 13 dat...
Network Based NLP Approach to Reveal Disease Comorbidities. COVID Case Study
Taylan , Emre; Pir, Pinar (Orta Doğu Teknik Üniversitesi Enformatik Enstitüsü; 2022-10)
SARS-CoV-2 virus, which caused the pandemic COVID-19 , infects the host cells via ACE2 receptor protein binding to spike proteins. Viral binding also alters the vascular effects of the ACE/ACE2 ratio, which results in a number of complications. These complications may have detrimental consequences on patients with chronic diseases such as diabetes, heart disease, tension-related disorders, and kidney disease, which already have an unbalanced ratio of ACE/ACE2. Due to this mechanism, COVID-19 is extremely co...
Deep learning for detection and segmentation of artefact and disease instances in gastrointestinal endoscopy
Ali, Sharib; et. al. (2021-05-01)
The Endoscopy Computer Vision Challenge (EndoCV) is a crowd-sourcing initiative to address eminent problems in developing reliable computer aided detection and diagnosis endoscopy systems and suggest a pathway for clinical translation of technologies. Whilst endoscopy is a widely used diagnostic and treatment tool for hollow-organs, there are several core challenges often faced by endoscopists, mainly: 1) presence of multi-class artefacts that hinder their visual interpretation, and 2) difficulty in identif...
Investigating possible involvement of miR-125b in the E2, NF-кB network
Yavuz, Esra; Erson Bensan, Ayşe Elif; Department of Biology (2015)
MicroRNAs (miRNAs) play important roles in diverse biological processes and are emerging as key regulators of tumorigenesis and tumor progression. Some miRNAs act as tumor suppressors and are downregulated in cancers such as miR-125b in breast cancer cell lines and tumors. Earlier, we developed a miR-125b expression model system and performed a transcriptomics experiment. Among many indirect targets, ALCAM (activated leukocyte antigen molecule) appeared to be very significantly upregulated in MCF7-125b cell...
Citation Formats
A. Ilgun and T. Cakir, “Network based approaches reveal cell subtype specific roles of astrocytes and oligodendrocytes during alzheimer’s disease,” Erdemli, Mersin, TÜRKİYE, 2022, p. 3080, Accessed: 00, 2023. [Online]. Available: https://hibit2022.ims.metu.edu.tr.