Effects of sodium DL-lactate on production of BDNF and inducible NOS in astrocytes and neurons cultures.

We analyzed the in vitro effects induced by Sodium DL-Lactate (SL) on primary cortical rat astrocytes and human neurons (SH-SY5Y cell line), when added at concentrations of 10, 25, and 50 mM, that are within the blood values before and after an exhaustive exercise.Expression of BDNF, iNOS and HSP70 was evaluated by Western blot analysis. Cell viability BDNF and NO release was also determined.In SH-SY5Y and in cortical astrocytes, after 4 h, SL increases the expression and release of BDNF, iNOS and NO; after 24 h, it turns out to be ineffective on the production of the neurotrophin in SH-SY5Y and not in astrocytes, but the expression of iNOS and release of NO appears to be further increased compared to that produced after 4 h. SL influences differently the expression of HSP70 in SH-SY5Y compared to astrocytes.We propose that the oxidative status affects in SHSY5Y the expression of BDNF: high levels of iNOS and NO expressed in neurons have a profound inhibitory effect on the release of BDNF related to a more limited production of HSP70 by neurons. Lactate may mediate neuroprotection indirectly by promoting astroglial BDNF expression in adverse situations such as high intensity exercise stresses.