CONICET | Buscador de Institutos y Recursos Humanos

Hypothesis: Periconceptional alcohol consumption alters preimplantational mouse embryo differentiation, probably inducing trophoblast dysfunction. Objective: to study the effects of periconceptional alcohol ingestion by CD-1 mice on in-vivo (day 5 of gestation) and in-vitro blastocyst development (outgrowth, migration and differentiation). Adult females were exposed to 10% ethanol in drinking water for 15 days previous to and up to 5 days of gestation (TF) (Control group [CF] - received only water). Recovered hatched blastocysts were cultured and at 0-24-48 and 72h to analyze the developmental dynamics (number [Nr] of cells/embryo), morphogenesis and, trophoblast growth (proliferative rate), differentiation (% diploid [CT] and giant trophoblast cells [GTC]) and migration (trophoblast expansion area ([TE]). Embryos were classified as small, medium and big according to TE area intervals. Results: TF presented diminished Nr blastocyts/female (p<0.05) and elevated percentage of abnormal embryos (p<0.05) vs CF. The percentage of small, medium and big embryos was invariable in CF through 48h-culture; at 48h, TF-bigger embryos % increased (p<0.05 vs 48h-CF) and small embryos showed an inverted pattern. Trophoblast nuclei Nr decreased in TF (p<0.05 vs CF, 72h-culture). TE of TF-small and medium embryos increased at 48 h-culture (p<0.05 vs CF). At 0-24h interval, both TE of TF-medium and big embryos decreased 14 and 28% vs controls, respectively. At 24-48 h interval, the same embryos increased 185% and 450% vs controls. TE of TF-small embryo increased in 6.4% and 11% at two intervals. The % of TGC and the mean TGC and CT area in TF group did not change. Conclusions: maternal alcohol ingestion in mouse lead to implanting embryo losses, morphological anomalies, growth alterations and deregulation of embryo and trophoblastic expansion/migration, suggesting trophoblast damage during implantation.