3,4-Methylenedioxy-N-methamphetamine (ecstasy) promotes the survival of fetal dopamine neurons in culture

Department of Psychiatry, University of Cincinnati, Cincinnati, OH 45267, USA.
Neuropharmacology (Impact Factor: 5.11). 10/2008; 55(5):851-9. DOI: 10.1016/j.neuropharm.2008.06.062
Source: PubMed


The current study examined whether modest concentrations of MDMA could increase the survival and/or neurite outgrowth of fetal midbrain dopamine (DA) neurons in vitro since increased DA neurite outgrowth has been previously observed in vivo from prenatal exposure. MDMA concentrations in fetal brain were quantified to determine relevant in vivo concentrations to employ in vitro. A dose response study in vitro demonstrated that MDMA, at concentrations observed in vivo, resulted in increased, DA-specific, neuron survival. Higher doses resulted in non-specific neurotoxicity. MDMA application immediately after culture establishment resulted in greater survival than delayed application, however both were superior to control. MDMA significantly increased the expression of the slc6a3 gene (dopamine transporter; DAT) in culture. Co-application of the DAT reuptake inhibitor methylphenidate (MPH) with MDMA attenuated this effect. Progressive reductions in MPH concentrations restored the MDMA-induced survival effect. This suggests that MDMA's action at DAT mediates the survival effect. Neurite density per neuron was unaffected by MDMA in vitro suggesting that MDMA promotes DA neuron survival but not neurite outgrowth in culture. Finally, animals prenatally exposed to MDMA and examined on postnatal day 35 showed an increase in tyrosine hydroxylase-positive (TH+) neurons in the substantia nigra but not in the ventral tegmental area. These data suggest that during development, MDMA can increase the survival of DA neurons through its action at its transporter. Understanding how MDMA increases DA neuron survival may provide insight into normal DA neuron loss during development.

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Available from: Caryl E Sortwell, Jan 31, 2014
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    • "The differentiation of ESCs via formation of aggregates or embryoid bodies (EB) progressively decreases the expression of mGlu5 (17-19). According to previous studies MDMA, despite being a toxic drug, enhances the differentiation and survival of DA neurons both in vivo and in vitro (20, 21); however no report regarding the effects of this compound in the early embryonic stage has been published. Considering the role of MDMA in releasing glutamate and mGlu5 in the maintenance and self-renewal of mESCs, this study aims to investigate whether MDMA could influence self-renewal via the mGlu5 receptor. "
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    ABSTRACT: Ecstasy, or 3, 4 (±) methylenedioxymethamphetamine (MDMA), is a potent neurotoxic drug. One of the mechanisms for its toxicity is the secondary release of glutamate. Mouse embryonic stem cells (mESCs) express only one glutamate receptor, the metabotropic glutamate receptor 5 (mGlu5), which is involved in the maintenance and self-renewal of mESCs. This study aims to investigate whether MDMA could influence self-renewal via the mGlu5 receptor in mESCs. In this expremental study, we used immunocytochemistry and reverse transcription-polymerase chain reaction (RT-PCR) to determine the presence of the mGlu5 receptor in mESCs. The expression of mGlu5 was evaluated after MDMA was added to mESCs throughout neural precursor cell formation as group 1 and during neural precursor cell differentiation as group 2. The stemness characteristic in treated mESCs by immunofluorescence and flow cytometry was studied. Finally, caspase activity was evaluated by fluorescence staining in the treated group. One-way ANOVA or repeated measure of ANOVA according to the experimental design was used for statistical analyses. In this study mGlu5 expression was shown in mESCs. In terms of neuronal differentiation, MDMA affected mGlu5 expression during neural precursor cell formation (group 1) and not during neural precursor differentiation (group 2). MDMA (450 µM) induced a significant increment in self-renewal properties in mESCs but did not reverse 2-methyl-6(phenylethynyl) pyridine (MPEP, 1 µM), a non-competitive selective mGlu5 antagonist. Fluorescence staining with anti-caspase 3 showed a significant increase in the number of apoptotic cells in the MDMA group. WE OBSERVED A DUAL ROLE FOR MDMA ON MESCS: reduced proliferation and maintenance of self-renewal. The lack of decreasing stemness characteristic in presence of MPEP suggests that MDMA mediates its role through a different mechanism that requires further investigation. In conclusion, despite being toxic, MDMA maintains stemness characteristics.
    Cell Journal 12/2012; 14(3):185-192. · 1.11 Impact Factor
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    • "In the present study, treatment of hippocampal primary cultures with low MDMA concentrations resulted in increased cell viability. A previous study using fetal mesencephalic cells reported similar increased cell survival in MDMA-treated cultures, compared with control culture [19] . That study used MDMA concentrations (0.165, 0.825, and 1.65 µg/mL) that were relatively low, as well as 96-hour incubation. "
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    ABSTRACT: effects of 3, 4-methylenedioxy-methamphetamine (ecstasy) on survival and apoptosis of primary hippocampal neurons. Neural Regen Res. 2009;4(12): Abstract BACKGROUND: 3, 4-methylenedioxymethamphetamine (MDMA, also known as "ecstasy") has been shown to exhibit neurotoxic effects on the hippocampus. However, exposure to sub-lethal insults of MDMA has been reported to result in neuroprotection. OBJECTIVE: To investigate the effects of MDMA on hippocampal neuronal viability, caspase-3 activity, and mRNA expression of the N-methyl-D-aspartate (NMDA) receptor 2B (NR2B) subunit. METHODS: Hippocampal neurons were isolated from Wistar rats at gestational day 18. Following primary culture, hippocampal neuronal viability was detected by MTT assay. Varying concentrations of MDMA (100-5 000 µmol/L) were used to determine lethal concentration 50 (LC50), which was around 1 500 µmol/L. Five concentrations of MDMA below 1 500 µmol/L (100, 200, 400, 800, and 1 050 µmol/L) were used for the remaining experiments. After 24 hours of MDMA treatment, NR2B mRNA expression was detected by RT-PCR, and caspase-3 relative activity was determined by colorimetric assay. MAIN OUTCOME MEASURES: Hippocampal neuronal viability, caspase-3 activity, and NR2B mRNA expression. RESULTS: MDMA-induced neurotoxicity in hippocampal neuronal cultures was dose-dependent. In high concentrations (1 000–5 000 µmol/L) of MDMA, neuronal viability was decreased. However, with a 500 µmol/L dose of MDMA, neuronal viability was significantly increased (P < 0.01). Low concentrations of MDMA (200 and 400 µmol/L) significantly decreased caspase-3 activity (P < 0.01), whereas high concentrations of MDMA significantly increased caspase-3 activity (P < 0.01). NR2B subunit mRNA expression was not significantly altered after 100-1 050 µmol/L MDMA exposure. CONCLUSION: MDMA exhibits dual effects on hippocampal neuronal viability and caspase-3 activity. These effects are independent from NR2B subunit expression levels.
    Neural Regeneration Research 12/2009; 4(12). DOI:10.3969/j.issn.1673-5374.2009.12.017 · 0.22 Impact Factor
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    • "Ventral mesencephalon (VM) from Fisher 344 rats of embryonic day 14 (E14) (crown-rump length = 10.0-11.5 mm) containing developing A8, A9 and A10 dopamine cell groups was dissected from the ventral floor of the midbrain flexure extending posteriorly to the isthmus, and laterally to the sulcus limitans (Lipton et al., 2008). After collection, VM tissue was pooled in 4°C calcium-magnesium free buffer, transferred to calcium-magnesium free buffer containing 0.1% trypsin, warmed to 37 °C for 10 minutes, rinsed in calcium-magnesium free buffer again, and triturated in 0.004% DNase using Pasteur pipettes of 1.0 mm and 0.5 mm tip diameter. "
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    ABSTRACT: Clinical trials of neural grafting for Parkinson's disease (PD) have produced variable, but overall disappointing, results. One particular disappointment has been the development of aberrant motor complications following dopamine (DA) neuron grafting. Despite a lack of consistent benefit, the utility of dopamine neuron replacement remains supported by clinical and basic data. In a continued effort to elucidate factors that might improve this therapy, we used a parkinsonian rat model to examine whether pregraft chronic levodopa affected graft efficacy and/or graft-induced dyskinesia (GID) induction. Indeed, all grafted PD patients to date have had a pregraft history of long-term levodopa. It is well established that long-term levodopa results in a plethora of long-lasting neurochemical alterations and genomic changes indicative of altered structural and synaptic plasticity. Thus, therapeutic dopamine terminal replacement in a striatal environment complicated by such changes could be expected to lead to abnormal or inappropriate connections between graft and host brain and to contribute to suboptimal efficacy and/or postgraft GID behaviors. To investigate the effect of pregraft levodopa, one group of parkinsonian rats received levodopa for 4 weeks prior to grafting. A second levodopa-naïve group was grafted, and the grafts were allowed to mature for 9 weeks prior to introducing chronic levodopa. We report here that, in parkinsonian rats, preexposure to chronic levodopa significantly reduces behavioral and neurochemical efficacy of embryonic dopamine grafts. Furthermore, dopamine terminal replacement prior to introduction of chronic levodopa is highly effective at preventing development of levodopa-induced dyskinesias, and GID-like behaviors occur regardless of pregraft levodopa status.
    The Journal of Comparative Neurology 07/2009; 515(1):15-30. DOI:10.1002/cne.22037 · 3.23 Impact Factor
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