Cryptosporidium parvum is a minimally invasive protozoal pathogen of intestinal epithelium that results in villus atrophy, mucosal lipid peroxidation, diarrhea, and diminished barrier function. Influx of neutrophils is a consistent feature of human and animal cryptosporidiosis, and yet their contribution to the pathological sequelae of infection has not been investigated. Accordingly, we used an established neonatal piglet model of C.
View Article and Find Full Text PDFAm J Physiol Gastrointest Liver Physiol
January 2006
Cryptosporidium sp. parasitizes intestinal epithelium, resulting in enterocyte loss, villous atrophy, and malabsorptive diarrhea. We have shown that mucosal expression of inducible nitric oxide (NO) synthase (iNOS) is increased in infected piglets and that inhibition of iNOS in vitro has no short-term effect on barrier function.
View Article and Find Full Text PDFIn intestinal inflammation, mucosal injury is often exacerbated by the reaction of NO with neutrophil-derived superoxide to form the potent oxidant peroxynitrite. Peroxynitrite also has antimicrobial properties that aid in the killing mechanism of macrophages and neutrophils. Cryptosporidium parvum parasitizes intestinal epithelium, resulting in loss of epithelial cells and mucosal inflammation.
View Article and Find Full Text PDFAm J Physiol Gastrointest Liver Physiol
September 2004
Cell culture models implicate increased nitric oxide (NO) synthesis as a cause of mucosal hyperpermeability in intestinal epithelial infection. NO may also mediate a multitude of subepithelial events, including activation of cyclooxygenases. We examined whether NO promotes barrier function via prostaglandin synthesis using Cryptosporidium parvum-infected ileal epithelium in residence with an intact submucosa.
View Article and Find Full Text PDFCryptosporidium parvum produces a prolonged watery diarrhea unresponsive to conventional antimicrobials. Because of reported efficacy of antibody-based immunotherapy, we studied the effect of inexpensive, commercially available oral bovine serum concentrate (BSC) in experimental cryptosporidiosis. Twenty-four calves were treated with 57 g/d BSC (n = 12) or soy protein (n = 12) added to their standard whey protein-based milk replacer (227 g/2 L twice daily).
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