Synthesis, uptake and release of taurine in astrocytes treated with 8-Br-cAMP

Taurine is one of the most abundant free amino acids in the mammalian central nervous system, where it is crucial for proper development. Moreover, taurine has been related with epilepsy, as it can reduce or prevent seizures. It is also a neuroprotectant in other experimental conditions. Glial cultures were analysed to determine the changes in taurine synthesis and traffic that occur in a more differentiated state of these cells. The cultures were treated with 8-Br-cAMP, an analogue of cAMP that induces differentiation in astrocytes. We observed an increase in immunoreactivity for GFAP, as well as an alteration in uptake-release kinetics in these cells. Moreover, we noted an increase in taurine levels and in cysteine sulfinic decarboxylase, which is the rate-limiting enzyme in taurine synthesis. The data indicate that taurine synthesis and traffic kinetics vary according to the differentiation state of the astrocytes. Thus, our results highlight the importance of astrocytes in modulating taurine levels in the brain.