Study And Application Of Microglia Activation Mechanism Based On Weighted Gene Co-expression Network Analysis(WGCNA)

【Objectives】Neuroinflammatory response is an important pathological basis of many nervous system diseases and activated microglia is one of the most important cellular components of neuroinflammation,which interact with neuronal cell and other central glial cells by secreting various cytokines.The present study attempts to identify gene module associated with the pathogenesis of microglia activation and search for drugs using bioinformatics.【Methods】Six GEO datasets(GSE18740,GSE23639,GSE49329,GSE70689,GSE102482 and GSE103156)were obtained from the NCBI-Gene Expression Omnibus(GEO)database.The weighted gene co-expression network analysis was performed to construct a co-expression network of genes correlated with microglia activation.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed to search for signaling pathways.The protein–protein interaction network analysis of central genes was performed to recognize the interactions among module genes.Cytoscape was used to look for the hub gene clusters involved in microglia activation.The cell viability was determined by MTT colorimetric assay to check the effect of GA3 on the cell viability of activated microglial.the expression of IL-6 and TNF-αwere measured by reverse transcription-polymerase chain reaction(RT-PCR)and enzyme-linked immunosorbent assay(ELISA)to analyze the mechanism of gibberellic acid on the activation of microglia.【Results】The pink module showed a pivotal correlation with microglia activation.A total of 154 genes in the pink module were identified based on the results of topological overlap measure–based clustering.Two hub gene clusters prominently associated with microglia activation were identified.NF-kappa B signal pathway、Toll-like receptor signal pathway、p53 signal pathway、MAPK signal pathway and Fox O signal pathway may be involved in microglia activation.Bioinformatics analysis revealed that gibberellic acid may antagonize m1-type activation of microglia cells induced by LPS.The results of reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay showed that gibberellic acid could antagonize the m1-type activation of microglia,and reduce the expression of il-6 and TNF-,and the anti-inflammatory capacity was positively correlated with the dose.【Conclusion】(1)NF-kappa B signal pathway、Toll-like receptor signal pathway、p53 signal pathway、MAPK signal pathway and Fox O signal pathway may be involved in microglia activation.(2)Gibberellic acid can antagonize M1-type activation of microglia and inhibit the release of its inflammatory factors.