Research Paper Volume 9, Issue 6 pp 1552—1564

Melatonin prevents postovulatory oocyte aging and promotes subsequent embryonic development in the pig

Figure 4. Effects of melatonin on ROS levels and total glutathione in aged oocytes. (A) Fresh oocytes. (B) Oocytes aged for 24 hr. (C) IVA 24 hr oocytes treated with 2 mM melatonin. (D) Oocytes aged for 48 hr. (E) IVA 48 hr oocytes treated with 2 mM melatonin. (F) ROS fluorescence pixel intensity in IVA oocytes. (G) ROS level (counts of photons) detection of single cell by optical nanoprobes. (H) Total glutathione (T-GSH) content in fresh and IVA oocytes. (I) The expression of anti-oxidative stress genes (SOD1, GPx4 and CAT) in fresh and aged oocytes. All graphs show mean ± s.e.m. Abbreviations used in this and all subsequent figures: ROS, reactive oxygen species. Independent replicates were conducted with a minimum of 30 oocytes/replicate, at least 3 stable replicates were obtained. **P <0.01, ***P <0.001. Bar = 50 μm.