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 microM final concentrations). In the presence of 0.5 microM 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 microM 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 microM 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 microM 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 microM resveratrol during culture has a positive effect on early embryonic development of porcine embryos.