Fig. 3

Fig. 3

NADPH-oxidase (Nox)-generated H₂O₂ is crucial for the hypoxia/re-oxygenation-induced embryonic catch-up growth. (A) Schematic diagram of NADPH oxidase (Nox) function, which produces H₂O₂, a redox signaling molecule, near the plasma membrane. The Nox inhibitor, VAS2870, reduces the Nox-dependent production of H₂O₂ in the vicinity of the plasma membrane. Most Nox generate superoxide which is converted to the H₂O₂ by superoxide dismutase (SOD). (B, C) Effects of the Nox-inhibitor VAS2870. Wild-type zebrafish embryos were raised following the experimental regime depicted in the panel (B) diagram. Head-Trunk Angle (HTA) was determined at the indicated time points (B). Data are average ± SD, n=9-20. (C) Changes in the relative growth rate of embryos in the Norm (26-38 hpf) and Reoxy (36-48 hpf) groups. The control (vehicle=0.1% DMSO) group was set as 100%. Data are mean ± SE of 3 independent experiments. Values marked with different letters (a, b, c) are significantly different from each other (P<0.05), but values marked with common letters (a and ab; ab and b) are not significantly different from each other (P>0.05). N.S. means not significantly different (P>0.05). (D) Changes in the relative growth rate of embryos in the Reoxy (36-48 hpf) embryos treated with or without VAS2870 and H₂O₂. The vehicle alone group was set as 100%. Data are mean ± SE of 3 independent experiments. Values marked with different letters (a, b) are significantly different from each other (P<0.05). (E) Changes in HTA of the Norm and Hypo embryos at 32 hpf with or without 8 hr H₂O₂ treatment. Data are average ± SD, n=18-20. The asterisk (*) denotes statistical difference at P<0.05. N.S. means not significantly different (P>0.05).