Fig. 3.

Effects of PEVs on oxidative stress, apoptosis, and senescence in degenerative NP cells. (A) Fluorescence images of NP cells with ROS staining by DCFH-DA probe. Scale bars ​= ​50 ​μm. (B) ROS level of NP cells according to (A). (C) The ROS level was determined by flow cytometry with DCFH-DA probe. (D) The ROS abundance of NP cells according to (C). (E–F) Detection of NP cells apoptosis by flow cytometry. (G–H) Detection of NP cells apoptosis by fluorescence confocal microscopy. Scale bars ​= ​50 ​μm. (I–J) NP cells senescence detection by SA-β-gal staining. Scale bars ​= ​50 ​μm. (K) The effects of PLTs and PEVs on mRNA expression levels of P16 and P21 in NP cells subjected to 100 ​μM ​H₂O₂ stimulation. Significance between four groups was calculated using one-way ANOVA with Tukey's post-hoc test. Data are presented as mean ​± ​SD (n ​= ​4). (Scale bars are listed above; ∗: P ​< ​0.05, ∗∗: P ​< ​0.01, ∗∗∗: P ​< ​0.005, and ∗∗∗∗: P ​< ​0.001).