[Analysis the mechanism of cadmium-induced cytotoxicity in mouse testicular mesenchymal cells with miRNA transcriptomic].

Objective: To analyze the mechanism of cadmium-induced cytotoxicity in mouse testicular mesenchymal cells(TM3) with transcriptome sequencing and bioinformatics techniques.

Methods: TM3 cells were selected as the cell model and divided into control group(no cadmium treatment) and cadmium-treated group(20 μmol/L CdCl_2). After 24 hours of administration, cells were harvested to extract total RNA, and then miRNA expression profiles were obtained by sequencing program after RNA quality detection. The fold change(FC) >2, P<0.05 was used as the standard to screen for differentially expressed miRNAs. The quantitative real-time polymerase chain reaction(qRT-PCR) was used to verify the differentially expressed miRNAs. Then, their target genes were predicted by miRanda software to construct miRNA-target gene interaction network, and their target genes were enriched by gene ontology(GO) and Kyoto encyclopedia of genes and genomes(KEGG) pathway function.

Results: A total of 26 differentially expressed miRNAs were identified which may be related to cadmium-induced TM3 cytotoxicity, including 19 up-regulated and 7 down-regulated miRNAs. The result of qRT-PCR were consistent with the miRNA sequencing result. Meanwhile, bioinformatics analysis result showed that the 26 differentially expressed miRNAs predicted 657 target genes. GO enrichment was mainly classified into biological regulation, metabolic process, protein binding and catalytic activity. KEGG pathway analysis showed that target genes were significantly involved in mitogen-activated protein kinase(MAPK) and tumor necrosis factor(TNF) signal pathways closely related to inflammatory response and apoptosis.

Conclusion: Cadmium can lead to the differential expression of miRNAs in TM3 cells, and its target genes may be involved in Cd-induced TM3 cytotoxicity through signaling pathways such as MAPK and TNF.