PubMed · 8026314
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
W Dorsch. 1994-07-08. [Bronchial asthma].. https://pubmed.ncbi.nlm.nih.gov/8026314/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Conjugation of ethylenediaminetetraacetic acid (EDTA) to ethyl phenylalaninate generates a novel radical scavenging metal-ion chelator EDTA bis-(ethyl phenylalaninate) (EBEP). The oxidation products o-, m- and p-tyrosine were isolated from hydrolysed, aqueous and aerated solutions containing EBEP, Fe(II) and H(2)O(2). Data obtained demonstrate the potential of EBEP to act as a radical scavenging, iron-ion chelating antioxidant under physiologically relevant conditions.
A novel polyunsaturated fatty acid (PUFA), beta-oxa 21:3n-3, containing an oxygen atom in the beta position, was chemically synthesized, and found to have more selective biological activity than the n-3 PUFA, docosahexaenoic acid (22:6n-3) on cells of the immune system. Although beta-oxa 21:3n-3 was very poor compared with 22:6n-3 at stimulating oxygen radical production in neutrophils, it was more effective at inhibiting human T lymphocyte proliferation (IC(50) of 1.9 vs 5.2 microM, respectively). beta-Oxa 21:3n-3 also inhibited the production of TNF-beta, IFN-gamma, and IL-2 by purified human T lymphocytes stimulated with PHA plus PMA, anti-CD3 plus anti-CD28 mAbs, or PMA plus A23187. Metabolism of beta-oxa 21:3n-3 via the cyclooxygenase and lipoxygenase pathways was not required for its inhibitory effects. Consistent with its ability to suppress T lymphocyte function, beta-oxa 21:3n-3 significantly inhibited the delayed-type hypersensitivity response and carrageenan-induced paw edema in mice. In T lymphocytes, beta-oxa 21:3n-3 inhibited the agonist-stimulated translocation of protein kinase C-betaI and -epsilon, but not -alpha, -betaII, or -theta to a particulate fraction, and also inhibited the activation of the extracellular signal-regulated protein kinase, but not c-Jun NH(2)-terminal kinase and p38. In contrast, 22:6n-3 had no effects on these protein kinase C isozymes. The increase in antiinflammatory activity and loss of unwanted bioaction through the generation of a novel synthetic 22:6n-3 analogue provides evidence for a novel strategy in the development of anti-inflammatory agents by chemically engineering PUFA.
IMPORTANCE OF ISCHEMIA-REPERFUSION LESIONS: After transplantation, ischemia-reperfusion lesions are associated with an increased risk of acute rejection, late recovery of liver function, or chronic graft dysfunction. In all, about 20% of the grafts are lost. The importance of prevention is evident. HEME-OXYGENASE: It has been shown that heme-oxygenase, an anti-oxidant reducing apoptosis, reduces the extent of ischemia-reperfusion lesions after liver, heart, kidney or Langerhans islet transplantation. OTHER COMPOUNDS WITH INTERESTING PROPERTIES: Other compounds also have interesting properties for preventing ischemia-reperfusion lesions: a specific metallo-protease inhibitor, L-arginine, a selective agonist of the PGE1 receptor, estrogens, low-dose cyclosporine, and certain immunosuppressors (FTY 720, anti CD28, anti B7-1), and rPSGL-Ig ligand.