MKK7-mediated phosphorylation of JNKs regulates the proliferation and apoptosis of human spermatogonial stem cells

Figure 5 Inhibition of c-Jun N-terminal kinase 1 phosphorylation inhibited proliferation and promoted apoptosis of human spermatogonial stem cells. A and B: Western blotting results showed that the phosphorylation of c-Jun N-terminal kinases was significantly inhibited by the c-Jun N-terminal kinase phosphorylation inhibitor, SP600125; C and D: The levels of proliferating cell nuclear antigen (PCNA) protein in human spermatogonial stem cells (SSCs) decreased significantly after treatment with SP600125; E: Cell counting kit (CCK)-8 results showed that the proliferation of SSCs was downregulated; F and G: EdU assays of DNA synthesis in human SSCs treated with SP600125; H and I: Terminal deoxynucleotidyl transferase nick-end-labeling (TUNEL) assay of the percentage of TUNEL+ cells in the human SSC line after SP600125 treatment; J-L: Flow cytometry and fluorescein isothiocyanate (FITC)/Annexin V analysis of the proportions of early (J and K) and late (J and L) apoptosis in the human SSC line treated with SP600125. Scale bars in F and H: 50 μm. ^aP < 0.05 denotes a significant difference between the Control and SP600125 treatment groups. p-JNK: Phosphorylated c-Jun N-terminal kinase; ACTB: Beta actin; DAPI: 4,6-diamidino-2-phenylindole.