Murine uterine receptivity markers are affected by particulate air pollution in a dose response manner

Abstract

Air pollution (AP) is associated with increased rates of implantation failures in mice. The uterus requires a variety of factors to become receptive: cytokines (LIF), anti-adhesion (MUC-1) molecules and hormonal induced morphological changes. This study investigated the effects of chronic exposure to AP on uterine receptivity. Female mice were exposed to either filtered air or 2 different daily doses of AP. Estrous cycle, ovarian and uterine weight, number of corpora lutea (CL), uterine histopathology, LIF and MUC-1 expression were evaluated. Effects were dose dependent. Estrous cycle showed shorter duration with extended diestrus. Ovarian weights were increased without change in CL number. Histopathology indicated a decrease in volume and thickness of endometrium and increased diameter and thickness of glandular and luminal epithelium. MUC-1 expression was not altered but LIF was decreased during the implantation window. This suggests that AP exposure negatively affects endometrial receptivity altering the fine regulation of decidualization mediated by LIF expression.