Periconceptional moderate alcohol ingestion alters the intercellular junctions of murine peri-implantantional embryos

Abstract

Murine consumption of alcohol produces perigestational anomalies in the differentiation and cavitation of peri-implantational blastocyst possibly related to intercellular adhesion defects. In CF-1 mouse females exposed to 10 % ethanol in drinking water for 17 days prior to fertilization and up to day 4 or 8 of gestation (TF) vs control females (water, CF) it was studied, by immunofluorescence (IF) single and double (confocal): 1) the location, pattern and the level of expression of E-cadherin and ZO-1 in blastocysts (Bl), 2) the expression of E-cadherin in embryos at gastrulation. While Bl from CF presented a continuous E-cadherin pattern in the mural trophectoderm cellular contacts (MT), polar (PT) and in the inner cell mass (ICM), Bl from TF, the E-cadherin was discontinuous, sinuous and was presented with membranous accumulations. In 40-50% of Bl from TF, the ZO-1 was expressed in MT, PT and ICM with a sub-membrane weak and discontinuous pattern but granular perinuclear and cytoplasmic expression. In TF, there was little co-localization between E- cadherin and ZO-1 vs CF, indicating impaired biogenesis joints in the preimplantation embryo. Embryonic ectoderm from TF had reduced expression of E-cadherin vs embryo-CF (p<0.05, Scion Image). In conclusion, the abnormal expression of E-cadherin and ZO-1 in TF suggests that weakening of cell junctions is involved in the alteration of Bl-cavitation while the loss of adherens junctions (E-cadherin) in the embryonic ectoderm can be related to dysmorphogenesis after alcohol exposure.

Keywords: alcohol, adhesion junctions, E-cadherin and ZO-1, peri-implantational embryos, mouse.