Ischemia and heavy alcohol consumption can cause brain damage inducing neuronal death by a cell death mode called apoptosis. Apoptosis is tightly regulated process in which the consecutive events go step by step, involving activation of many specific proteins which gradually destroy the cell. The stagewise nature of this degradation gives a possibility by clinical intervention to save neurons from apoptosis and to reduce significantly the serious consequences of ischemia and excessive alcohol consumption. Among candidate drugs in this context the amino acid taurine seems particularly attractive, since it is a naturally occurring non-toxic compound abounding in the nervous system. It is involved in a wide range of physiological processes and has beneficial effects in cell protection. This study describes the protective effects of taurine against apoptotic cell death in ischemia- and alcohol-induced brain damage as well as the toxic effect of a combination of large doses of taurine with alcohol.

We have found in the in vitro experiments in adult mice that taurine (20 mM) protects hypothalamic neurons from apoptosis induced by ischemia. Then, in 7-day-old mice, taurine (2 g/kg) protected about 50 % of dying cerebellar neurons against alcohol-induced apoptosis. On the other hand, any further increase in taurine doses (4-6 g/kg) aiming to protect more neurons against alcohol-induced apoptosis poses to threat to the whole organism and kills 7-day-old mice thus treated. The experiments on adult and old mice showed that one reason for this toxicity may be dramatically drop of blood sugar level. Based on the results obtained we conclude that taurine may have beneficial effects in protecting brain cells against the apoptosis induced by ischemia and alcohol. However, our finding on the toxicity of combined taurine and ethanol prompts serious concern particularly for young people mixing taurine-containing energy drinks with alcohol.