Induction of Lipopolysaccharide During Pregnancy Will Suppress IL-6 Production but not Activin B

Purpose: The purpose of this study was to investigate the response of interleukin-6 (IL-6) and activin B in pregnant mice following induction with lipopolysaccharide (LPS). Given the known role of proinflammatory cytokines such as IL-6 and activin B in inflammation, and the potential modulation of their production by estradiol, which is elevated during pregnancy, this research aimed to understand the impact of pregnancy on the inflammatory response in mice. Methods: The study involved two groups of mice: one group consisted of 8 non-pregnant mice, while the other comprised 13 pregnant mice in the second week of gestation. Inflammation was induced in the mice through intraperitoneal injection of LPS from Escherichia coli serotype O111:B4. After 4 hours of treatment, serum samples were collected from the mice's intracardiac blood to measure levels of estradiol, IL-6, and activin B using enzyme-linked immunosorbent assay (ELISA). Results and Discussion: The results showed that pregnancy significantly reduced IL-6 levels (P=0.015), indicating a suppression of proinflammatory cytokine production during gestation. However, there was no significant difference in estradiol (P=0.169) and activin B (P=0.583) levels between pregnant and non-pregnant mice following LPS induction. Additionally, no significant association was found between estradiol and IL-6 (P=0.637) or activin B (P=0.306). These findings suggest that while pregnancy influences the inflammatory response, particularly affecting IL-6 levels, it may not directly modulate estradiol and activin B production in the context of acute inflammation induced by LPS. Implications of the Research: The observed reduction in IL-6 levels during pregnancy following LPS induction highlights the complex interplay between pregnancy and the immune system. Understanding how pregnancy influences inflammatory responses can have implications for managing inflammatory conditions in pregnant individuals and developing targeted interventions to mitigate potential risks associated with altered immune function during gestation. Originality/Value: This research contributes to the existing knowledge by elucidating the specific effects of pregnancy on the production of IL-6 and activin B in response to inflammatory stimuli. By focusing on a murine model and employing ELISA to quantify cytokine levels, this study provides valuable insights into the immunomodulatory effects of pregnancy, shedding light on the mechanisms underlying altered inflammatory responses during gestation.