IκBNS and IL-6 expression is differentially established in the uterus of pregnant healthy and infected mice

• Main Authors: Fernando Gómez-Chávez, Óscar Humberto López-Portales, Damariz Adriana Baeza-Martínez, Juan Carlos Cancino-Díaz, José Martín Murrieta-Coxca, Mario Eugenio Cancino-Díaz, Sonia Mayra Pérez-Tapia, Sandra Rodríguez-Martínez
• Format: Article
• Language: English
• Published: Elsevier 2020-06-01
• Series: Heliyon
• Subjects: Biological sciences; Immunology; Health sciences; Women's health; Reproductive system; IL-6
• Online Access: http://www.sciencedirect.com/science/article/pii/S240584402030966X

During pregnancy, NF-κB plays an important role for embryo implantation and the onset of labor. Regulated IL-6 production, under transcriptional control of NF-κB, is essential for a successful pregnancy outcome and the atypical regulator IκBNS is involved in this process. Previously, we showed that IκBNS negatively regulates IL-6 in uterine tissues during mouse estrous cycle. In this work, we analyzed if IκBNS and IL-6 expression in pregnant mice under physiological or L. monocytogenes-infected conditions would remain as observed in estrous cycle. In the healthy pregnancy IL-6 was highly expressed during implantation/placentation and labor stages but decreased during fetal development and post-partum stages. In contrast, in mice infected before pregnancy, IL-6 expression was not increased in the implantation stage, and its regulator IκBNS increased more in the infected condition rather than in the healthy pregnancy. IκBNS expression was reduced in post-implantation infection, allowing for IL-6 overexpression. The IκBNS-unrelated cytokine IL-36γ, used as inflammatory cytokine marker, was severely increased in the infected uterine tissues. When we analyzed the effect of infection over the fetuses, we found that pre-implantation infection caused the resorption (rejection) of some products, while the post-implantation infection restricted the intrauterine growth of fetuses. The results suggest that in the uterine tissue of pregnant mice the regulatory effect of IκBNS over IL-6 is more evident in an infection status rather than in a healthy condition.