Faculty Collaboration Database

Intestinal NADPH oxidase 2 activity increases in a neonatal rat model of necrotizing enterocolitis. PLoS One 2014;9(12):e115317

Date

12/18/2014

Pubmed ID

25517730

Pubmed Central ID

PMC4269454

DOI

10.1371/journal.pone.0115317

Scopus ID

2-s2.0-84919466804 (requires institutional sign-in at Scopus site)   8 Citations

Abstract

Necrotizing enterocolitis (NEC) is a complication of prematurity. The etiology is unknown, but is related to enteral feeding, ischemia, infection, and inflammation. Reactive oxygen species production, most notably superoxide, increases in NEC. NADPH oxidase (NOX) generates superoxide, but its activity in NEC remains unknown. We hypothesize that NOX-derived superoxide production increases in NEC. Newborn Sprague-Dawley rats were divided into control, formula-fed, formula/LPS, formula/hypoxia, and NEC (formula, hypoxia, and LPS). Intestinal homogenates were analyzed for NADPH-dependent superoxide production. Changes in superoxide levels on days 0-4 were measured. Inhibitors for nitric oxide synthase (L-NAME) and NOX2 (GP91-ds-tat) were utilized. RT-PCR for eNOS, NOX1, GP91phox expression was performed. Immunofluorescence studies estimated the co-localization of p47phox and GP91phox in control and NEC animals on D1, D2, and D4. NEC pups generated more superoxide than controls on D4, while all other groups were unchanged. NADPH-dependent superoxide production was greater in NEC on days 0, 3, and 4. GP91-ds-tat decreased superoxide production in both groups, with greater inhibition in NEC. L-NAME did not alter superoxide production. Temporally, superoxide production varied minimally in controls. In NEC, superoxide generation was decreased on day 1, but increased on days 3-4. GP91phox expression was higher in NEC on days 2 and 4. NOX1 and eNOS expression were unchanged from controls. GP91phox and p47phox had minimal co-localization in all control samples and NEC samples on D1 and D2, but had increased co-localization on D4. In conclusion, this study proves that experimentally-induced NEC increases small intestinal NOX activity. All components of NEC model are necessary for increased NOX activity. NOX2 is the major source, especially as the disease progresses.

Author List

Welak SR, Rentea RM, Teng RJ, Heinzerling N, Biesterveld B, Liedel JL, Pritchard KA Jr, Fredrich KM, Gourlay DM

Authors

David M. Gourlay MD Chief, Professor in the Surgery department at Medical College of Wisconsin
Kirkwood A. Pritchard PhD Professor in the Surgery department at Medical College of Wisconsin
Ru-Jeng Teng MD Professor in the Pediatrics department at Medical College of Wisconsin
Scott R. Welak MD Associate Professor in the Pediatrics department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Animals, Newborn
Disease Models, Animal
Enteral Nutrition
Enterocolitis, Necrotizing
Enzyme Inhibitors
Female
Fluorescent Antibody Technique
Hypoxia
Intestines
Membrane Glycoproteins
NADPH Oxidase 2
NADPH Oxidases
NG-Nitroarginine Methyl Ester
Nitric Oxide
Nitric Oxide Synthase
RNA, Messenger
Rats
Rats, Sprague-Dawley
Real-Time Polymerase Chain Reaction
Reverse Transcriptase Polymerase Chain Reaction
Superoxides
Tumor Necrosis Factor-alpha