Bioinformatics analysis of transcriptome sequencing after the interference of extremely low frequency electromagnetic field in mouse fibroblasts

Objective

To analyze the changes in the transcriptome of mouse fibroblasts after exposure to extremely low frequency electromagnetic fields (ELF-EMFs) using next-generation sequencing technology, and to screen out related pathways and genes that might be involved in the regulation of fibroblast growth by ELF-EMFs.

Methods

The mouse NIH/3T3 cells were divided into the radiation group and the normal control group.The cells in the radiation group were placed in a 0.2 mT, 50 Hz electromagnetic radiation system, and the cells in the normal control group was placed in the same coil system under the same conditions without power.After 24-hour culture in a cell incubator, RNA was extracted.The next-generation high-throughput sequencing technology was used to sequence the transcriptomes of the two groups, and perform gene function annotation and signal pathway database analysis on the selected differential genes.Some highly expressed genes were screened out and verified by real-time fluorescent quantitative PCR.

Results

A total of 17 980 genes were identified in the transcriptome sequencing, and there were 140 significantly differentially expressed genes (DEGs), of which 120 were up-regulated and 20 were down-regulated.DEGs were enriched in enzyme catalytic activity, cell metabolism process, biological regulation, biosynthesis and so on.According to the Kyoto Encyclopedia of Genes and Genomes analysis, the DEGs mainly involved 55 pathways, among which the most enriched 10 pathways were aminoacyl-tRNA biosynthesis, platelet activation, neurotrophin signaling pathway, renin-angiotensin system, etc., closely related to cell biosynthesis.The DEGs that might be involved in the post-irradiation stress of cells were further screened out, including mitogen activated protein kinase 12 (MAPK12), neurotrophic tyrosine kinase receptor type 3 (NTRK3), angiotensin Ⅱ receptor type 2 (AGTR2), vascular endothelial growth factor (VEGF), etc.Real-time fluorescent quantitative PCR results showed that the relative expression levels of MAPK12, NTRK3, AGTR2, VEGF mRNA in the radiation group were 2.389±0.003, 2.481±0.350, 2.354±0.081, 1.559±0.110, respectively, which were significantly higher than 1.011±0.190, 1.011±0.180, 1.007±0.150, 1.008±0.153, respectively in the normal control group (t=12.540, 6.309, 13.710, 3.078; all at P<0.05).

Conclusions

After the mouse fibroblasts were interfered with ELF-EMFs, the expression levels of MAPK12, NTRK3, AGTR2, VEGF and other genes are significantly up-regulated, which mainly involve neurotrophin signaling pathway, renin-angiotensin system and other pathways.These genes and pathways may be the main way that ELF-EMFs affect fibroblasts.

Electromagnetic radiation; Extremely low frequency electromagnetic fields; Fibroblasts; Signaling pathways; Genome; Bioinformatics