FIGURE 3.

NA supplement partially prevents the meiotic defects and oxidative stress in oocytes with NAMPT deficiency. (a,b) Quantitative analysis of GVBD and Pb1 extrusion in control (n = 138) and FK866‐treated (n = 124 for 25 µM, n = 119 for 50 µM, n = 116 for 100 µM) oocytes. (c) Quantitative analysis of Pb1 extrusion in oocytes after FK866 washout (n = 81 for control, n = 87 for FK866, and n = 73 for washout). (d) Quantitative analysis of Pb1 extrusion in FK866 (n = 93), FK866 + NMN (n = 112), and FK866 + NA (n = 105) oocytes. (e) NAD⁺ content in control, FK866, and FK866 + NA oocytes (n = 150 for each group). (f) Representative images of control, FK866, and FK866 + NA oocytes stained with α‐tubulin antibody to visualize the spindle (green) and with propidium iodide to visualize chromosomes (red). Spindle disorganization and chromosome misalignment are indicated by arrowheads. Scale bars: 30 µm. (g) Quantitative analysis of meiotic defects in control (n = 138), FK866 (n = 124), and FK866 + NA (n = 105) oocytes. (h) Representative images of CM‐H2DCFDA fluorescence (green) in oocytes from control, FK866, and FK866 + NA oocytes. Scale bars: 50 µm. (i) Relative ROS levels in control, FK866, and FK866 + NA oocytes. Each data point represents an oocyte (n = 15 for each group). Data are expressed as the mean ± SD from three independent experiments. Statistical analyses were performed with one‐way ANOVA with Tukey's post hoc test. **p < 0.01, ***p < 0.001. GVBD, germinal vesicle breakdown; n.s., not significant; NA, nicotinic acid; NAMPT, nicotinamide phosphoribosyl transferase