Figure 1.

 Influence of different concentrations of curcumin on GVBD, first meiotic cleavage of oocytes and second and subsequent mitotic divisions of embryos. (A) Percentage of control and curcumin‐treated GV oocytes, which underwent GVBD, measured after 1.5 and 2.5 h of culture; each group contained ∼65 oocytes. (B) First meiosis completion of control and curcumin‐treated GV oocytes. GVBD – oocytes started meiotic resumption but did not extrude I polar body (Ipb). Ipb – oocytes emitted first polar body; control n = 193, curcumin: 10, 20 μm n = about 60, 30 μm n = 171, 40, 50 μm n = about 100 (n means number of oocytes). For statistical analysis, control and curcumin‐treated oocytes that extruded I pb were compared. (C) Completion of second and subsequent mitotic divisions in control and curcumin‐treated two‐cell embryos (9 and 24 h of culture with different concentrations of curcumin). 2‐cell, 4‐cell, 8‐cell describe two‐, four‐ and eight‐cell embryos. Each group contained ∼50 embryos. For statistical analysis, control and curcumin‐treated embryos that achieved four‐cell stage (9 h) or eight‐cell stage (24 h) were compared; Student’s t‐test; *P < 0.05, **P < 0.01, ***P < 0.001. Data were collected from six independent experiments. Curcumin delayed and partially inhibited GVBD in a dose‐dependent manner (A). Curcumin in a dose‐dependent manner decreased the ability to finish the first meiotic division (B) and second and subsequent mitotic cleavages (C). 50 μm curcumin inhibited meiotic and mitotic cleavages and after 24 h caused fragmentation all of the two‐cell embryos.