Submitted to: Society for Neuroscience Abstracts and Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 6/10/2004
Publication Date: 6/10/2004
Citation: Xie, T., Tong, L., Mccann, U., Yuan, J., Becker, K., Mechan, A., Cheadle, C., Donovan, D.M., Ricaurte, G. 2004. Identification and characterization of metallothionein-1 and 2 gene expression in the context of (±)3,4-methylenedioxymethamphetamine (mdma)-induced toxicity to brain dopaminergic neurons. Society for Neuroscience Abstracts and Proceedings. 24(32):7043-7050.
Technical Abstract: The recreational drug, (±)3,4-methylenedioxymethamphetamine (MDMA, "ecstasy"), produces a selective toxic effect on brain dopamine (DA) neurons in mice. Using cDNA microarray technology in combination with an approach designed to facilitate recognition of relevant changes in gene expression, the present studies sought to identify genes potentially involved in murine MDMA-induced toxicity to DA neurons. Out of 15,000 mouse cDNA fragments studied, metallothionein (Mt)-1 and Mt2 emerged as candidate genes possibly involved in MDMA-induced toxicity to DA neurons. Northern blot analysis confirmed the microarray findings and revealed a dynamic up-regulation of Mt1 and Mt2 mRNA in the ventral midbrain within 4-12 hr after MDMA treatment. Western blot analysis showed a similar increase in Mt protein levels, with peak times occurring subsequent to increases in mRNA levels. Mt1-2 double knockout (KO) mice were more vulnerable to MDMA-induced toxicity to DA neurons than corresponding wild-type mice. Stimulation of endogenous expression of Mt protein with zinc acetate conferred complete protection against MDMA-induced toxicity to DA neurons, and administration of exogenous Mt protein afforded partial protection. Collectively, these results indicate that MDMA-induced toxicity to DA neurons is associated with increased Mt1 and Mt2 gene transcription and translation, possibly as part of a neuroprotective mechanism. The present findings may have therapeutic implications for neuropathological conditions involving DA neurons.