J. Shah1,2, S. B. Deas2,3, J. H. Neilson2,3, C. Ren4, T. Jilling4, K. M. Brawner2, C. A. Martin2 1University Of Alabama at Birmingham,Department Of Clinical & Diagnostic Sciences,Birmingham, Alabama, USA 2University Of Alabama at Birmingham,Department Of Surgery,Birmingham, Alabama, USA 3University Of Alabama at Birmingham,Department Of Medicine,Birmingham, Alabama, USA 4University Of Alabama at Birmingham,Department Of Pediatrics,Birmingham, Alabama, USA
Introduction: Psychological stress during pregnancy has been shown to cause subsequent harm to the fetus and newborn. Many studies focus on neurodevelopmental outcomes, but little is known about the effect of gestational stress on intestinal immunity and development. We have shown that psychological stress disrupts immune development, but its effect on intestinal development is not known. The purpose of this study was to determine the effect of psychological stress during pregnancy on the newborn’s intestinal architecture and growth.
Methods: 8-week-old C57BL/6 littermates underwent timed breeding. Pregnant dams were subjected to one hour of daily psychological stress by using a well-established restraint model during days E7-E14 of the gestational period. The distal ileum of 2-week-old offspring of stressed mothers and non-stressed controls was harvested for histological analysis. Slides were blinded and Axiovision Rel. 4.7 software was used to measure villus height and crypt depth. To determine the effect of excess stress hormones on intestinal proliferation, an explant model was used. 2 mm biopsies were taken from wild type non-stressed mice and treated with 100 mM of corticosterone for 24 hours. RNA was isolated and RT-PCR was performed to determine the effect of corticosterone on the intestinal stem cell marker Leucine-rich-repeat-containing G-protein-coupled Receptor 5 (LGR5) and growth factors Epidermal Growth Factor Receptor (EGFR) and Insulin Growth Factor-1 (IGF-1). A non-parametric T test was used to determine any significant differences between the groups. Results were expressed as the mean SEM.
Results: 7 mice were included in each group. The villus height was 126.4 5.6 m for control and 100.4 4.5 m for stress mice, p value <0.05. The crypt depth was 63.9 1.2 m for control and 53.7 2.3 m for the stressed group, p value <0.05. RT-PCR revealed that explants exposed to corticosterone had a 2.1-fold increase in LGR5 compared to controls, p value = 0.04. There was no significant difference in the IGF-1 and EGFR expression between control and treatment groups.
Conclusion: Here we establish that neonatal mice with mothers that were subjected to psychological stress during pregnancy have significantly shorter villi and crypts compared to controls. In addition, pups from stressed mothers had higher expression levels of the intestinal stem cell marker LGR5, which may suggest a compensatory response to stress. Future studies will further clarify the temporal relationship between intrauterine stress and intestinal development as well as the mechanisms of how excess stress hormones affect neonatal intestinal development. These findings will aid in determining the effect of gestational psychological stress on intestinal development and stem cell proliferation