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Tom H Johnston,
Zak Millar,
Philippe Huot,
Keith Wagg,
Sherri Thiele,
Danielle Salomonczyk,
Christopher J Yong-Kee, Michael N Gandy,
Matthew McIldowie,
Katie D Lewis,
Jordi Gomez-Ramirez,
Joohyung Lee,
Susan H Fox,
Mathew Martin-Iverson,
Joanne E Nash,
Matthew J Piggott,
Jonathan M Brotchie
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ABSTRACT: Treatment of Parkinson's disease with dopaminergic agents, such as l-DOPA, is frequently compromised by disabling side effects, particularly dyskinesia and a shortening in duration of antiparkinsonian action. Studies in animal models and anecdotal evidence from a patient with Parkinson's disease show that the illicit drug ecstasy (MDMA) can alleviate these side effects, though with many drawbacks (e.g., psychoactivity). MDMA itself thus has little therapeutic potential. On the basis of known structure-psychoactivity relationships, we designed a series of α-substituted MDMA analogues, one of which, bearing an α-cyclopropyl substituent (UWA-101), enhanced the quality of l-DOPA actions in animal models. Indeed, UWA-101 was more effective than MDMA. Unlike MDMA, UWA-101 did not reduce viability of serotonergic cells, exhibit psychoactive properties, or reduce food intake, and did not substitute for MDMA in drug discrimination assays. UWA-101 displayed a unique receptor/transporter binding profile relative to MDMA, with a >5-fold decrease in affinity for NET and 5-HT(2A) receptors and a 10-fold increase in affinity for DAT. Furthermore, in a functional reuptake assay, UWA-101 inhibited both 5-HT and dopamine reuptake, while having no effect on the reuptake of noradrenaline. UWA-101 is the first selective DAT/SERT inhibitor described with comparable affinities for these two sites. These data identify a new class of therapeutic in Parkinson's disease and highlight the potential benefits of studying illicit drugs that in themselves would never be considered safe for long-term therapy.
The FASEB Journal 02/2012; 26(5):2154-63. · 5.71 Impact Factor
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ABSTRACT: The wearing-OFF phenomenon is a common motor complication of chronic L-3,4-dihydroxyphenylalanine (L-DOPA) therapy for Parkinson's disease. We recently described the discovery of UWA-101, a dual serotonin (SERT) and dopamine (DAT) transporter inhibitor, which increases the duration of "good quality" ON-time provided by L-DOPA in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned primate. Here, we further characterise the effects of UWA-101 on this extension of ON-time in terms of L-DOPA-induced side-effects in the MPTP-lesioned common marmoset.
Marmosets were rendered parkinsonian by MPTP injection and "primed" by repeated L-DOPA administration, to exhibit dyskinesia and psychosis-like behaviours. Animals were then administered acute challenges of L-DOPA in combination with UWA-101 (1, 3, 6 and 10 mg/kg) or vehicle.
In combination with L-DOPA, UWA-101 (3, 6 and 10 mg/kg) significantly increased duration of ON-time (by 28%, 28%, and 33%, respectively; all P<0.05). UWA-101 (10 mg/kg) significantly extended duration of ON-time without disabling dyskinesia (by 62%, P<0.01). UWA-101 did not exacerbate the severity of dyskinesia (P>0.05). However, at the highest doses (6 and 10 mg/kg), UWA-101 increased the severity of psychosis-like behaviours (P<0.05).
Our results demonstrate that dual SERT/ DAT inhibitors can effectively enhance L-DOPA anti-parkinsonian action, without exacerbating dyskinesia and, as such, represent a promising new therapeutic class for wearing-OFF. However, at higher doses, dual SERT/ DAT inhibitors may exacerbate dopaminergic psychosis.
PLoS ONE 01/2012; 7(9):e45587. · 4.09 Impact Factor
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Agata M Wasik, Michael N Gandy,
Matthew McIldowie,
Michelle J Holder,
Anita Chamba,
Anita Challa,
Katie D Lewis,
Stephen P Young,
Dagmar Scheel-Toellner,
Martin J Dyer,
Nicholas M Barnes,
Matthew J Piggott,
John Gordon
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ABSTRACT: While 3,4-methylenedioxymethamphetamine (MDMA/'ecstasy') is cytostatic towards lymphoma cells in vitro, the concentrations required militate against its translation directly to a therapeutic in vivo. The possibility of 'redesigning the designer drug', separating desired anti-lymphoma activity from unwanted psychoactivity and neurotoxicity, was therefore mooted. From an initial analysis of MDMA analogues synthesized with a modified α-substituent, it was found that incorporating a phenyl group increased potency against sensitive, Bcl-2-deplete, Burkitt's lymphoma (BL) cells 10-fold relative to MDMA. From this lead, related analogs were synthesized with the 'best' compounds (containing 1- and 2-naphthyl and para-biphenyl substituents) some 100-fold more potent than MDMA versus the BL target. When assessed against derived lines from a diversity of B-cell tumors MDMA analogues were seen to impact the broad spectrum of malignancy. Expressing a BCL2 transgene in BL cells afforded only scant protection against the analogues and across the malignancies no significant correlation between constitutive Bcl-2 levels and sensitivity to compounds was observed. Bcl-2-deplete cells displayed hallmarks of apoptotic death in response to the analogues while BCL2 overexpressing equivalents died in a caspase-3-independent manner. Despite lymphoma cells expressing monoamine transporters, their pharmacological blockade failed to reverse the anti-lymphoma actions of the analogues studied. Neither did reactive oxygen species account for ensuing cell death. Enhanced cytotoxic performance did however track with predicted lipophilicity amongst the designed compounds. In conclusion, MDMA analogues have been discovered with enhanced cytotoxic efficacy against lymphoma subtypes amongst which high-level Bcl-2--often a barrier to drug performance for this indication--fails to protect.
Investigational New Drugs 08/2011; 30(4):1471-83. · 3.36 Impact Factor
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ABSTRACT: Synthesis of iminosugar-based affinity-based proteomics probes for use in probing exo-α-glycosidase activity.
Chemical Communications 03/2011; 47(17):5037-9. · 6.17 Impact Factor
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ABSTRACT: An improved medium scale synthesis of 3-[(2-methyl-1,3-thiazol-4-yl)ethynyl]pyridine (MTEP), a selective and potent metabotropic glutamate subtype 5 (mGlu5) antagonist, has allowed thorough characterisation of the crystal structures of the free base and the previously unreported hydrochloride (MTEP.HCl). Hirshfeld surface analysis has revealed that molecules in crystalline MTEP are weakly polar, and aggregate through nonclassical C--H...N hydrogen bonds. A strong ionic N--H(+)...Cl(-) hydrogen bond dominates the crystal packing in MTEP.HCl. Despite significant differences in the crystal packing, the molecular structures of MTEP and MTEP.HCl are very similar. The acid dissociation constants for MTEP were investigated using (1)H NMR spectroscopy. The second acid dissociation constant (pK(a2)), associated with the pyridine nitrogen, was determined to be 3.40 +/- 0.01, whilst pK(a1), associated with the thiazole nitrogen, was estimated to be 0.2. The low pK(a) values make it unlikely that MTEP is protonated in its biologically active form.
Journal of Pharmaceutical Sciences 07/2009; 99(1):234-45. · 3.06 Impact Factor
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ABSTRACT: The first total synthesis of the azaanthracene kalasinamide (1) is described, and the discrepancy in the reported (13)C NMR data and melting points for the natural product from two different sources is resolved. Kalasinamide is prone to autosensitized photooxidation, in solution and in the solid state, to give the corresponding quinone, marcanine A (8). This transformation may be representative of a novel and more general step in the biosynthesis of (aza)anthraquinones. Through its ability to generate toxic singlet oxygen, kalasinamide may serve a protective role, defending the plant against predation and the invasion of microbial pathogens, following mechanical insult.
Journal of Natural Products 06/2008; 71(5):866-8. · 3.13 Impact Factor
