Gene Expression Analysis of the Human Astrocytoma Cell after Abeta25-35 Stimulation Followed by Ibuprofen Administration

Choi, Youngsook; Eun, Jungwoo; Nam, Sukwoo; Kim, Sangho

Abstract

BACKGROUND
The molecular events leading to the development of sporadic late-onset Alzheimer's disease (AD) have not been defined. A number of mechanism for the protective effects of non-steroidal anti-inflammatory drugs (NSAIDs) in AD have been proposed. We investigated the ibuprofen effect of global gene expression on the amyloid-beta25-35 (Abeta25-35)-stimulated human astrocytoma cell.
METHODS
U373MG, a human astrocytoma cell line, was incubated with 25 microM of aggregated Abeta25-35 or aggregated Abeta25-35 plus 100 microM ibuprofen at 37degrees C for 24 hours. Cells treated with ibuprofen alone were used as the negative control. Differential gene expression analysis was carried out with the Illumina human whole genome microarray. Real-time reverse transcriptase polymerase chain reaction (RT-PCR) was also done to validate the gene expression changes. After Welch's t-test, the significant subset of outlier genes were identified by an expression change cut-off 1.5 fold, p<0.05. Kyoto Encyclopedia of Genes and Genomes database was used for cellular signaling pathway analysis.
RESULTS
A total of 371 differentially expressed genes were identified from 16,692 detectable signals in Abeta25-35 peptide stimulated U373MG cells- 182 up-regulated genes with 21 biological pathways including biosynthesis of steroid, peroxisome proliferator-activated receptor signaling pathway and focal adhesion and 189 down-regulated genes with 14 biological pathways including transforming growth factor-beta signaling pathway, axon guidance and mitogen activated protein kinase signaling pathway. Ibuprofen suppressed the up-regulated expression of immunity/inflammation (especially, SERPINE1), signal pathway, metabolism and cancer-related genes. The expression of microarray data was confirmed by real-time RT-PCR.
CONCLUSION
Aggregated Abeta25-35 induces expression of widespread transcriptional alterations, namely 21 functional groups 182 up-regulated genes and 14 functional groups 189 down-regulated genes in U373MG cells. Ibuprofen, a commonly used NSAID, suppressed Abeta25-35-induced increase of global changes in transcription of sets of genes especially immunity/inflammation, signal pathway, metabolism and cancer-related genes.