J.T. Davies1, R. Cheddadi1, V. Yeramilli1, C.A. Martin1 1Washington University, Department Of Surgery, Division Of Pediatric Surgery, St. Louis, MO, USA
Introduction:
Maternal stress during pregnancy has been associated with several neonatal outcomes including those that impact intestinal development in the newborn—especially in premature and very low birth weight infants. Elucidating the effects of parental stress and downstream signaling on gut maturation is a critical area of research with significant implications in disease prevention and treatment, namely with respect to necrotizing enterocolitis (NEC) a devastating intestinal disease with very high morbidity and mortality with very limited treatment options. The nematode Caenorhabditis Elegans (C. elegans) is a well-established model for studying stress signaling pathways. In this study, we investigated the impact of heat stress on intestinal integrity and permeability in C. elegans.
Methods:
Eggs from adult wild-type (N2) C. elegans worms were isolated and allowed to hatch into L1 larvae. L1 larvae were then transferred to NGM plates seeded with E. coli OP50 and incubated for 24 hours at an optimal growth temperature of 20°C to reach the L2 larvae stage. Now synchronized worms were then separated randomly into 2 treatment groups (28°C and 30°C) and 1 control group (20°C) with each group containing 2 plates each. Each group was then incubated for 48 hours at their respective temperatures. The worms from each plate were then washed and transferred to and incubated on fresh NGM plates seeded with a mixture of fluorescein isothiocyanate (FITC)-dextran (an intestinal permeability marker) and E. coli OP50 for 18 hours. Worms were washed from their plates, ensuring only intracorporal FITC remain, and single worms were transferred and fixated. The intestinal permeability was then examined using fluorescence high-throughput image analysis.
Results:
The mean fluorescence intensities of worms from the control (20°C) and 28°C-treatment groups were 59.281 ± 10.010 and 88.638 ± 14.678, respectively; there was a significant difference in fluorescence intensities (p < 0.05) between these two groups. The 30°C-treatment group was unable to be analyzed due to the inadequate number and size of worms.
Conclusion:
This study demonstrates the effects of heat stress on intestinal permeability in a wild-type C. elegans model. As evidenced by a significant increased fluorescence intensity in the 28°C-treatment group as compared to control, our results suggest that on some level, exposure to heat stress during development may compromise gut integrity and permeability. Future studies will look at this key finding across generations and will seek to understand the mechanism driving this finding.