Enzymatic-nonenzymatic cellular antioxidant defense systems response and immunohistochemical detection of MDMA, VMAT2, HSP70, and apoptosis as biomarkers for MDMA (Ecstasy) neurotoxicity

3,4-Methylenedioxymethamphetamine (MDMA)-induced neurotoxicity leads to the formation of quinone metabo- lities and hydroxyl radicals and then to the production of reactive oxygen species (ROS). We evaluated the effect of a single dose of MDMA (20 mg/kg, i.p.) on the enzymatic and nonenzymatic cellular antioxidant defense system in different areas of rat brain in the early hours (<6 hr) of the administration itself, and we identified the morphological expressions of neurotoxic- ity induced by MDMA on the vulnerable brain areas in the first 24 hr. The acute administration of MDMA pro- duces a decrease of reduced and oxidized glutathione ratio, and antioxidant enzyme activities were signifi- cantly reduced after 3 hr and after 6 hr in frontal cortex. Ascorbic acid levels strongly increased in striatum, hip- pocampus, and frontal cortex after 3 and 6 hr. High lev- els of malonaldehyde with respect to control were measured in striatum after 3 and 6 hr and in hippocam- pus and frontal cortex after 6 hr. An immunohistochem- ical investigation on the frontal, thalamic, hypothalamic, and striatal areas was performed. A strong positive reaction to the antivesicular monoamine transporter 2 was observed in the frontal section, in the basal ganglia and thalamus. Cortical positivity, located in the most superficial layer was revealed only for heat shock pro- tein 70 after 24 hr.