Fertilization and early embryology: Polyamines may increase the percentage of in-vitro fertilized murine oocytes that develop into blastocysts

This study was designed to investigate whether the polyaminesspermine, spermidine and putrescine can prevent the arrest ofdevelopment of in-vitro fertilized murine oocytes from CD1 strainmice. Development in M16 or Brinster's medium with or withoutpolyamine supplementation was assessed and the ability of blastocyststo attach and grow out on laminin was compared with in-vivo-generatedembryo blastocysts. Oocytes from old (20 weeks) females showedlower rates of fertilization and subsequent development in comparisonwith oocytes from young (6–8 weeks old) females, but inboth cases <5% of in-vitro fertilized oocytes achieved theblastocyst stage. In-vitro fertilized young oocytes showed enhanceddevelopment to the blastocyst stage with the addition of thepolyamine putrescine, although lesser enhancement was seen withspermine and spermidine; this effect was only evident when theoocytes were grown in Brinster's medium, reflecting the needfor a particular set of culture conditions for growth-enhancingagents to be effective. Blastocysts generated in putrescine-supplementedBrinster's medium were able to implant on laminin-coated surfacesin vitro and to respond to the cytokines colony-stimulatingfactor-1, epidermal growth factor and platelet-derived growthfactor with increased trophoblast outgrowth to a greater degreethan in-vivo-generated blastocysts. Murine in-vitro fertilizedembryo development was not enhanced by co-culture with Verocells. Putrescine was the most effective polyamine, enhancingthe in-vitro fertilized oocyte development to blastocysts ina permissive environment.