Uptake of Taurine and Taurine Chloramine in Murine Macrophages and their Distribution in Mice with Experimental Inflammation
Taurine is an abundant amino acid in inflammatory cells, where it acts as a trap for toxic hypochlorous acid (HOCl/OCl−) and protects tissue from damage resulting from overt inflammatory reactions as demonstrated in vivo and in vitro models of inflammation7,10,11. High concentrations of taurine are present in the cytosol of leukocytes (20–50 mM)4,8. Under physiological conditions the formation of taurine chloramine (Tau-Cl) is catalyzed by a reaction of the polymorphonuclear leukocytes (PMN) derived from myeloperoxidase (MPO) and hypochlorous acid with taurine. Formation of Tau-Cl may also be catalyzed directly by a halide-dependent myeloperoxidase reaction not involving formation of HOCl/OCl−. Although Tau-Cl inherently possesses oxidative potential, it is more stable and less toxic than HOCl. The addition of exogenous taurine strongly enhances chloramine formation. Tau-Cl plays a role in inflammation by inhibiting the production of nitric oxide, TNF-α, IL-1, IL-6, IL-8 and prostaglandin E2 in macrophages and production of superoxide anion (O2−) in PMN7,10,11,12
KeywordsPhenol Superoxide Prostaglandin Cytosol HEPES
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