Analysis of the resistance of small peptides from Periplaneta americana to hydrogen peroxide-induced apoptosis in human ovarian granular cells based on RNA-seq.

Apoptosis of ovarian granular cells is closely related with weakening fertility of women. Hence, resisting apoptosis of human ovarian granular cells is of important significance. According to previous studies, DAPI fluorescence staining experiment and Western Blot test of Caspase-3 demonstrate that small peptides from Periplaneta americana (SPPA) can improve hydrogen peroxide (HO) -induced apoptosis of human ovarian granular cells (KGN cells). However, the molecular mechanism of SPPA resistance against apoptosis of granular cells still remains unknown. In this study, key genes and signaling pathways for SPPA to resist HO-induced apoptosis of KGN cells were determined through transcriptome sequencing (RNA-seq). Experiments were divided into three groups, namely, the control group, HO group and HO + SPPA group. A total of 1196 differentially expressed genes (DEGs) were screened by comparing the control group and the HO group, and 2805 DEGs were screened by comparing the HO group and HO + SPPA group. It is important to note that 87 overlapping genes were identified upregulating in HO exposure, but downregulating in SPPA repair. Another 151 overlapping genes were identified downregulating in HO exposure, but upregulating in SPPA repair. These 238 overlapping genes have significant enrichment in multiple KEGG pathways. Among them, 13 genes play significant roles in SPPA resistance process of cell apoptosis: EIF3D, RAN, UPF1 and EIF2B4 participate in RNA transport; ACTG1, SIPA1 and CTNND1 participate in Leukocyte transendothelial migration; S100A7, S100A9, RELA and IL17RE participate in IL-17 signaling pathway; BCL2L13, EIF2AK3 and RELA participate in Mitophapy-animal. Ten genes were selected for florescence quantitative PCR (qPCR) verification and the expression level was consistent with sequencing results. Finally, a control network of SPPA resistance against the HO-induced KGN cell apoptosis was built based on the target genes screened by the RNA-seq technology. This study provides a direction and some references to further understand the molecular mechanism of SPPA resistance against the HO-induced KGN cell apoptosis.