The enteropathy of prostaglandin deficiency
Rent the article at a discountRent now
* Final gross prices may vary according to local VAT.Get Access
Small intestinal ulcers are frequent complications of therapy with nonsteroidal anti-inflammatory drugs (NSAIDs). We present here a genetic deficiency of eicosanoid biosynthesis that illuminates the mechanism of NSAID-induced ulcers of the small intestine.
Eicosanoids and metabolites were measured by isotope dilution with mass spectrometry. cDNA was obtained by reverse transcription and sequenced following amplification with RT-PCR.
We investigated the cause of chronic recurrent small intestinal ulcers, small bowel perforations, and gastrointestinal blood loss in a 45-year-old man who was not taking any cyclooxygenase inhibitor. Prostaglandin metabolites in urine were significantly depressed. Serum thromboxane B2 (TxB2) production was 4.6% of normal controls (P < 0.006), and serum 12-HETE was 1.3% of controls (P < 0.005). Optical platelet aggregation with simultaneous monitoring of ATP release demonstrated absent granule secretion in response to ADP and a blunted aggregation response to ADP and collagen, but normal response to arachidonic acid (AA). LTB4 biosynthesis by ionophore-activated leukocytes was only 3% of controls, and urinary LTE4 was undetectable. These findings suggested deficient AA release from membrane phospholipids by cytosolic phospholipase A2-α (cPLA2-α), which regulates cyclooxygenase- and lipoxygenase-mediated eicosanoid production by catalyzing the release of their substrate, AA. Sequencing of cPLA2-α cDNA demonstrated two heterozygous nonsynonymous single-base-pair mutations: Ser111Pro (S111P) and Arg485His (R485H), as well as a known single nucleotide polymorphism (SNP), Lys651Arg (K651R).
Characterization of this cPLA2-α deficiency provides support for the importance of prostaglandins in protecting small intestinal integrity and indicates that loss of prostaglandin biosynthesis is sufficient to produce small intestinal ulcers.
- The enteropathy of prostaglandin deficiency
Journal of Gastroenterology
Volume 44, Issue 19 Supplement, pp 1-7
- Cover Date
- Print ISSN
- Online ISSN
- Springer Japan
- Additional Links
- small intestinal ulcer
- cytosolic phospholipase A2
- nonsteroidal antiinflammatory drugs
- Industry Sectors
- Author Affiliations
- 1. Departments of Medicine and Pharmacology, Division of Clinical Pharmacology, Vanderbilt University, Vanderbilt Medical Center, 1211 Medical Center Drive, Nashville, TN, 37232, USA
- 2. Department of Pediatrics, Division of Medical Genetics, Vanderbilt Medical Center, Nashville, TN, USA
- 3. Department of Pharmacology, Vanderbilt University, Vanderbilt Medical Center, Nashville, TN, USA
- 6. Center for Human Genetics Research, Vanderbilt University, Vanderbilt Medical Center, Nashville, TN, USA
- 4. Department of Medicine, Division of Digestive and Liver Diseases, Columbia University, New York, NY, USA
- 5. School of Medicine, University of California, San Diego, La Jolla, CA, USA