Sa2011 Adverse Metabolic Effects of Indomethacin on the Immature Human Intestine

Abstract

Background: Indomethacin (INDO) is a non-steroidal anti-inflammatory drug (NSAID) used for the treatment of patent ductus arteriosus in preterm infants and as a tocolytic agent in pregnant women. The exposure of preterm infants to INDO is associated with an increased risk of developing enteropathies such as necrotizing enterocolitis. Despite increasing progress in establishing the pathways involved in NSAID-induced damage, understanding the pathogenesis of gastrointestinal injury by NSAIDs in neonates relies on a limited number of studies carried out in animal models. Aims: In the present study, we combined our method for maintaining the mid-gestation human intestine in serum-free organ culture with highthroughput genomic studies and bioinformatic pathway analysis to investigate the specific intestinal effects of INDO on the overall physiology of both the small and large intestine at mid-gestation. Methods: After determining the optimal concentration of INDO to be 1μM (.90% inhibition of intestinal prostaglandin E2 production), a dose that corresponds to the range of circulating levels in treated preterm babies, we used Illumina microarrays to establish global gene expression profiles in human intestinal explants (ileums and colons) in response to an INDO treatment of 48 h. Differentially expressed genes between control and INDO-treated explants were determined using the Mann-Whitney test (p , 0.05), and further analyzed with Ingenuity Pathway Analysis software (IPA 8.8) to identify biological functions and canonical pathways modulated by INDO. Results: The gene expression profiles identified revealed that a large proportion of statistically significant biological, physiological and metabolic functions were modulated by INDO in the immature intestine. As expected, a number of these significantly modulated functions were inflammation-related such as Inflammatory diseases, Inflammatory response, and Acute phase response. Noteworthily, we have identified a series of metabolic-related gene clusters that were found to be significantly modulated, namely Glycolysis/gluconeogenesis, Oxidative phosphorylation and Free radical scavenging/oxidoreductase activity. Further analysis by qPCR confirmed that the expression of representative genes involved in these metabolic functions, such as ALDOA, LDHA, NDUFA9, DUOX2, SOD2, and TFF1, was inhibited by INDO in both intestinal segments, indicating that this adverse metabolic effect could be a component of the pathogenesis of intestinal damage induced by INDO. Conclusion: This study identified several different metabolic pathways that are modulated by INDO in the immature human intestine and suggests a mechanistic basis for better understanding the contributing effects of INDO and other NSAIDs on neonatal intestinal pathologies.