Direct reaction of taurine with malondialdehyde: evidence for taurine as a scavenger of reactive carbonyl species

Though taurine has been reported very useful in preventing oxidative stress and various age-related diseases, the detailed biochemical mechanism of its biological functions is not well understood. Direct reaction of malondialdehyde (MDA) with taurine was studied using spectrofluorometry, spectrophotometry and liquid chromatography online with mass spectrometry (LC/MS). The results indicated that taurine reacted readily with MDA at supraphysiological conditions to yield mainly two products: a fluorescent 1,4-dihydropyridine and non-fluorescent enaminal derivatives. Taurine also significantly inhibited the formation of lipofuscin-like fluorescence induced by MDA-modified bovine serum albumin. These findings suggested that taurine effectively reduces carbonyl stress due to the amino group in its molecular structure, and we propose that it should be the mechanism related with the pathophysiological functions of taurine in the biological system.