Taurine chloramine inhibits prostaglandin E2

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Prostaglandin E2 (PGE2) is highly inflammatory. Inflammation is associated with major depressive disorder. Taurine chloramine inhibits PGE2.

Taurine chloramine inhibits prostaglandin E2 production in activated RAW 264.7 cells by post-transcriptional effects on inducible cyclooxygenase expression.

Quinn MR, Park E, Schuller-Levis G.

Abstract

Taurine chloramine (Tau-Cl) was recently demonstrated to inhibit production of nitric oxide and tumor necrosis factor-alpha (TNF-alpha) by activated macrophages. Since increased production of prostaglandin E2 (PGE2), a reaction catalyzed by induction of cyclooxygenase-2 (COX-2), is also associated with the inflammatory response, we determined the effects of Tau-Cl on PGE2 production and on expression of COX-2 protein and COX-2 mRNA in activated RAW 264.7 cells, a murine macrophage-like cell line. Tau-Cl inhibited production of PGE2 in a concentration dependent manner with an IC50 of 0.4 mM. The decrease in PGE2 production was largely accounted for by decreased expression of COX-2 protein. Although the kinetics of COX-2 mRNA expression was altered in Tau-Cl treated cells, mRNA expression appeared to be quantitatively unimpaired. These results suggest that Tau-Cl affects the post-transcriptional regulation of COX-2 expression and support the idea that Tau-Cl may function as an inhibitory modulator of the inflammatory response.

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Selective inhibition of cyclooxygenase 2-generated prostaglandin E2 synthesis in rheumatoid arthritis synoviocytes by taurine chloramine.

Kontny E, Rudnicka W, Kowalczewski J, Marcinkiewicz J, Maslinski W.

Objective: To investigate the effects of taurine chloramine (Tau-Cl), a chlorinated derivative of the amino acid taurine, on the expression of cyclooxygenase (COX) isoenzymes and prostaglandin E(2) (PGE(2)) synthesis in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS).

Methods: FLS, isolated from the synovial tissue of RA patients, were treated in vitro with either interleukin-1beta (IL-1beta; 1 ng/ml) alone or together with 200-500 microM Tau-Cl. The expression of COX isoenzymes was evaluated at both the protein (Western blotting) and the messenger RNA (mRNA) (reverse transcriptase-polymerase chain reaction) levels. The concentration of PGE(2) was measured by competitive acetylcholinesterase enzyme immunoassay.

Results: Resting FLS expressed mRNA encoding both COX-1 and COX-2, but only COX-1 was present at the protein level. These cells produced negligible amounts of PGE(2). Upon stimulation with IL-1beta, elevation of COX-2, but not COX-1, mRNA and protein preceded the enhancement of PGE(2) synthesis. In the presence of 300-400 microM Tau-Cl, significant inhibition of IL-1beta-triggered COX-2 mRNA and protein, and a related decrease in PGE(2) production, was observed. In contrast, no significant changes in COX-1 mRNA and protein levels were noted.

Conclusion: Tau-Cl inhibits IL-1beta-triggered elevation of COX-2 and generation of PGE(2) by RA FLS. These results expand the spectrum of known antiinflammatory activities of this compound.

Taurine chloramine downregulates the production of proinflammatory mediators

Taurine chloramine produced from taurine under inflammation provides anti-inflamnatory and cytoprotective effects

Chaekyun Kim  1 Young-Nam Cha

Abstract

Taurine is one of the most abundant non-essential amino acid in mammals and has many physiological functions in the nervous, cardiovascular, renal, endocrine, and immune systems. Upon inflammation, taurine undergoes halogenation in phagocytes and is converted to taurine chloramine (TauCl) and taurine bromamine. In the activated neutrophils, TauCl is produced by reaction with hypochlorite (HOCl) generated by the halide-dependent myeloperoxidase system. TauCl is released from activated neutrophils following their apoptosis and inhibits the production of inflammatory mediators such as, superoxide anion, nitric oxide, tumor necrosis factor-α, interleukins, and prostaglandins in inflammatory cells at inflammatory tissues. Furthermore, TauCl increases the expressions of antioxidant proteins, such as heme oxygenase 1, peroxiredoxin, thioredoxin, glutathione peroxidase, and catalase in macrophages. Thus, a central role of TauCl produced by activated neutrophils is to trigger the resolution of inflammation and protect macrophages and surrounding tissues from being damaged by cytotoxic reactive oxygen metabolites overproduced during inflammation. This is achieved by attenuating further production of proinflammatory cytokines and reactive oxygen metabolites and also by increasing the levels of antioxidant proteins that are able to scavenge and diminish the production of cytotoxic oxygen metabolites. These findings suggest that TauCl released from activated neutrophils may be involved in the recovery processes of cells affected by inflammatory oxidative stresses and thus TauCl could be used as a potential physiological agent to control pathogenic symptoms of chronic inflammatory diseases.

Inflammation, taurine and essential fatty acids in schizophrenia, Parkinson’s disease and Alzheimer’s disease

Inflammation is associated with schizophrenia, Parkinson’s disease and Alzheimer’s disease. A point I have strongly stressed is that the transsulfuration pathway is dysregulated in many neurological illnesses. With the transsulfuration pathway dysregulated there will de decreased levels of L-cysteine which is synthesized via the transsulfuration pathway. Decreased levels of l-cysteine will lead to decreased levels of taurine. Taurine is synthesized from L-cysteine. The bile acid, taurocholate, is synthesized from taurine. With low levels of taurine, essential fatty acids are not absorbed sufficiently. Inflammation in schizophrenia, Parkinson’s disease and Alsheimer’s disease could be due to low levels of taurine which leads to failures to absorb sufficient fatty acids with inflammation resulting.

Taurine chloramine which is synthesized from taurine is also an important immunomodulatory.