Effect of Resveratrol on the Development of Porcine Embryos Produced In Vitro

The effects of resveratrol (a phytoalexin with a wide variety of pharmacological activities) on pig embryos produced by parthenogenesis and/or in vitro fertilization have been investigated. First, parthenogenetic embryos were generated and cultured in PZM-3 medium supplemented with various amounts of resveratrol (0, 0.05, 0.1, 0.5, 1.0 and 25 mu M final concentrations). In the presence of 0.5 mu M resveratrol a significantly higher percentage of parthenogenetic embryos reached the blastocyst stage by day 7 compared to non-treated control (43.5 +/- 6.3% vs. 33.0 +/- 5.4%; P<0.05). The total cell number of blastocysts also increased as a result of incubation with 0.5 mu M resveratrol; the difference was statistically significant between treated and non-treated embryos on day 5 of culture (35.8 +/- 0.9 vs. 32.1 +/- 1.1; P<0.05). Resveratrol incubation affected the expression levels of apoptosis-related genes in parthenogenetic blastocysts: the level of Bax transcripts was similar but lower expression of Bcl-2 and Caspase-3 was observed in embryos treated with 0.5 mu M resveratrol when compared to control blastocysts (P<0.05). The results of the TUNEL assay were similar in blastocysts developing with or without resveratrol supplementation. In addition, when embryos produced by in vitro fertilization were incubated with 0.5 mu M resveratrol, the treatment led to higher frequencies of blastocyst formation (8.6% vs. 13.3%) and elevated total cell numbers (37.1 +/- 2.4 vs. 43.2 +/- 1.7) by the end of the 7-day culture period (P<0.05). The results indicate that 0.5 mu M resveratrol during culture has a positive effect on early embryonic development of porcine embryos.