Transcriptome analysis reveals the mechanism of Rhodiola polysaccharide affecting the proliferation of porcine Leydig cells under hypoxia

Hypoxia can affect the function of the male reproductive system and reduce fertility. Rhodiola polysaccharide (RDP) is the active ingredient of Rhodiola rosea L. and has a positive effect on reproductive cells. However, the mechanism of the effect of RDP on the proliferation of cells under hypoxia is still unclear. The experiment selected porcine Leydig cells (PLCs) as the test object and divided them into three groups: normal group, hypoxia group, and hypoxia + RDP-treated group. Cell viability was detected using CCK8 assay. RNA-Seq technology was used to identify the key genes that influence the effect of RDP on PLCs under hypoxia conditions and to determine their regulatory pathways. Transcriptome sequencing of PLCs from the N and H groups identified 6,794 differentially expressed genes (DEGs), including 3,329 up-regulated genes and 3,465 down-regulated genes. These DEGs were significantly enriched in the cell cycle signaling pathway, indicating that hypoxia mainly affects the cell cycle and inhibits cell proliferation. Furthermore, comparison of the transcriptomes between the H and HR group revealed 285 DEGs, including 137 up-regulated and 148 down-regulated, most of DEGs were found to be enriched in oxidative phosphorylation pathways. RDP inhibits PLCs apoptosis and promotes cell proliferation by up-regulating the expression of CXCL2, JUNB and VCAM1 of the TNF signaling pathway, and VEGFA, SGK2 and SPP1 of the PI3K/AKT signaling pathway. These genes deserve further study as candidate for understanding the role of RDP in alleviating the hypoxia stress.