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Rentsch P, Egan T, Kuriakose A, Stayte S, Vissel B. The ratio of M1 to M2 microglia in the striatum determines the severity of L-Dopa-induced dyskinesias. J Neurochem 2023; 167:633-647. [PMID: 37916541 DOI: 10.1111/jnc.15993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 09/27/2023] [Accepted: 09/30/2023] [Indexed: 11/03/2023]
Abstract
L-Dopa, while treating motor symptoms of Parkinson's disease, can lead to debilitating L-Dopa-induced dyskinesias, limiting its use. To investigate the causative relationship between neuro-inflammation and dyskinesias, we assessed if striatal M1 and M2 microglia numbers correlated with dyskinesia severity and whether the anti-inflammatories, minocycline and indomethacin, reverse these numbers and mitigate against dyskinesia. In 6-OHDA lesioned mice, we used stereology to assess numbers of striatal M1 and M2 microglia populations in non-lesioned (naïve) and lesioned mice that either received no L-Dopa (PD), remained non-dyskinetic even after L-Dopa (non-LID) or became dyskinetic after L-Dopa treatment (LID). We also assessed the effect of minocycline/indomethacin treatment on striatal M1 and M2 microglia and its anti-dyskinetic potential via AIMs scoring. We report that L-Dopa treatment leading to LIDs exacerbates activated microglia numbers beyond that associated with the PD state; the severity of LIDs is strongly correlated to the ratio of the striatal M1 to M2 microglial numbers; in non-dyskinetic mice, there is no M1/M2 microglia ratio increase above that seen in PD mice; and reducing M1/M2 microglia ratio using anti-inflammatories is anti-dyskinetic. Parkinson's disease is associated with increased inflammation, but this is insufficient to underpin dyskinesia. Given that L-Dopa-treated non-LID mice show the same ratio of M1/M2 microglia as PD mice that received no L-Dopa, and, given minocycline/indomethacin reduces both the ratio of M1/M2 microglia and dyskinesia severity, our data suggest the increased microglial M1/M2 ratio that occurs following L-Dopa treatment is a contributing cause of dyskinesias.
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Affiliation(s)
- Peggy Rentsch
- St. Vincent's Centre for Applied Medical Research, Sydney, New South Wales, Australia
- UNSW St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Timothy Egan
- St. Vincent's Centre for Applied Medical Research, Sydney, New South Wales, Australia
- UNSW St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Andrea Kuriakose
- Centre for Motor Neuron Disease Research, Macquarie Medical School, Faculty of Medicine, Macquarie University, Sydney, New South Wales, Australia
| | - Sandy Stayte
- St. Vincent's Centre for Applied Medical Research, Sydney, New South Wales, Australia
| | - Bryce Vissel
- St. Vincent's Centre for Applied Medical Research, Sydney, New South Wales, Australia
- UNSW St Vincent's Clinical School, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
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2
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Stayte S, Dhungana A, Vissel B, Bradfield LA. Parafascicular Thalamic and Orbitofrontal Cortical Inputs to Striatum Represent States for Goal-Directed Action Selection. Front Behav Neurosci 2021; 15:655029. [PMID: 33841111 PMCID: PMC8029974 DOI: 10.3389/fnbeh.2021.655029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 03/01/2021] [Indexed: 12/02/2022] Open
Abstract
Several lines of evidence accrued over the last 5–10 years have converged to suggest that the parafascicular nucleus of the thalamus and the lateral orbitofrontal cortex each represent or contribute to internal state/context representations that guide action selection in partially observable task situations. In rodents, inactivations of each structure have been found to selectively impair performance in paradigms testing goal-directed action selection, but only when that action selection relies on state representations. Electrophysiological evidence has suggested that each structure achieves this function via inputs onto cholinergic interneurons (CINs) in the dorsomedial striatum. Here, we briefly review these studies, then point to anatomical evidence regarding the afferents of each structure and what they suggest about the specific features that each contribute to internal state representations. Finally, we speculate as to whether this role might be achieved interdependently through direct PF→OFC projections, or through the convergence of independent direct orbitofrontal cortex (OFC) and parafascicular nucleus of the thalamus (PF) inputs onto striatal targets.
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Affiliation(s)
- Sandy Stayte
- Centre for Neuroscience and Regenerative Medicine, University of Technology Sydney, Sydney, NSW, Australia.,St. Vincent's Centre for Applied Medical Research, St. Vincent's Hospital Sydney, Sydney, NSW, Australia
| | - Amolika Dhungana
- Centre for Neuroscience and Regenerative Medicine, University of Technology Sydney, Sydney, NSW, Australia.,St. Vincent's Centre for Applied Medical Research, St. Vincent's Hospital Sydney, Sydney, NSW, Australia
| | - Bryce Vissel
- Centre for Neuroscience and Regenerative Medicine, University of Technology Sydney, Sydney, NSW, Australia.,St. Vincent's Centre for Applied Medical Research, St. Vincent's Hospital Sydney, Sydney, NSW, Australia
| | - Laura A Bradfield
- Centre for Neuroscience and Regenerative Medicine, University of Technology Sydney, Sydney, NSW, Australia.,St. Vincent's Centre for Applied Medical Research, St. Vincent's Hospital Sydney, Sydney, NSW, Australia
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3
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Chen H, Wang B, Li G, Steele JR, Stayte S, Vissel B, Chan YL, Yi C, Saad S, Machaalani R, Oliver BG. Brain health is independently impaired by E-vaping and high-fat diet. Brain Behav Immun 2021; 92:57-66. [PMID: 33221488 DOI: 10.1016/j.bbi.2020.11.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 11/02/2020] [Accepted: 11/18/2020] [Indexed: 12/30/2022] Open
Abstract
Tobacco smoking and high-fat diet (HFD) independently impair short-term memory. E-cigarettes produce e-vapour containing flavourings and nicotine. Here, we investigated whether e-vapour inhalation interacts with HFD to affect short-term memory and neural integrity. Balb/c mice (7 weeks, male) were fed a HFD (43% fat, 20 kJ/g) for 16 weeks. In the last 6 weeks, half of the mice were exposed to tobacco-flavoured e-vapour from nicotine-containing (18 mg/L) or nicotine-free (0 mg/L) e-fluids twice daily. Short-term memory function was measured in week 15. HFD alone did not impair memory function, but increased brain phosphorylated (p)-Tau and astrogliosis marker, while neuron and microglia levels were decreased. E-vapour exposure significantly impaired short-term memory function independent of diet and nicotine. Nicotine free e-vapour induced greater changes compared to the nicotine e-vapour and included, increased systemic cytokines, increased brain p-Tau and decreased postsynaptic density protein (PSD)-95 levels in chow-fed mice, and decreased astrogliosis marker, increased microglia and increased glycogen synthase kinase levels in HFD-fed mice. Increased hippocampal apoptosis was also differentially observed in chow and HFD mice. In conclusion, E-vapour exposure impaired short-term memory independent of diet and nicotine, and was correlated to increased systemic inflammation, reduced PSD-95 level and increased astrogliosis in chow-fed mice, but decreased gliosis and increased microglia in HFD-fed mice, indicating the inflammatory nature of e-vapour leading to short term memory impairment.
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Affiliation(s)
- Hui Chen
- School of Life Sciences, Faculty of Science, University of Technology Sydney, NSW 2007, Australia
| | - Baoming Wang
- School of Life Sciences, Faculty of Science, University of Technology Sydney, NSW 2007, Australia; Respiratory Cellular and Molecular Biology, Woolcock Institute of Medical Research, NSW 2037, Australia
| | - Gerard Li
- School of Life Sciences, Faculty of Science, University of Technology Sydney, NSW 2007, Australia
| | - Joel R Steele
- School of Life Sciences, Faculty of Science, University of Technology Sydney, NSW 2007, Australia
| | - Sandy Stayte
- Centre for Neuroscience and Regenerative Medicine, Faculty of Science, University of Technology Sydney, NSW, Australia; St Vincent's Centre for Applied Medical Research, St Vincent's Health Network Sydney, NSW 2010, Australia
| | - Bryce Vissel
- Centre for Neuroscience and Regenerative Medicine, Faculty of Science, University of Technology Sydney, NSW, Australia; St Vincent's Centre for Applied Medical Research, St Vincent's Health Network Sydney, NSW 2010, Australia
| | - Yik Lung Chan
- School of Life Sciences, Faculty of Science, University of Technology Sydney, NSW 2007, Australia; Respiratory Cellular and Molecular Biology, Woolcock Institute of Medical Research, NSW 2037, Australia
| | - Chenju Yi
- Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518107, China.
| | - Sonia Saad
- Kolling Institute of Medical Research, Royal North Shore Hospital, University of Sydney, NSW 2065, Australia
| | - Rita Machaalani
- SIDS and Sleep Apnea Laboratory, Sydney Medical School (Central), University of Sydney, NSW 2006, Australia
| | - Brian G Oliver
- School of Life Sciences, Faculty of Science, University of Technology Sydney, NSW 2007, Australia; Respiratory Cellular and Molecular Biology, Woolcock Institute of Medical Research, NSW 2037, Australia.
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Stayte S, Laloli KJ, Rentsch P, Lowth A, Li KM, Pickford R, Vissel B. The kainate receptor antagonist UBP310 but not single deletion of GluK1, GluK2, or GluK3 subunits, inhibits MPTP-induced degeneration in the mouse midbrain. Exp Neurol 2020; 323:113062. [PMID: 31513786 DOI: 10.1016/j.expneurol.2019.113062] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 08/20/2019] [Accepted: 09/07/2019] [Indexed: 12/31/2022]
Abstract
The excitatory neurotransmitter glutamate is essential in basal ganglia motor circuits and has long been thought to contribute to cell death and degeneration in Parkinson's disease (PD). While previous research has shown a significant role of NMDA and AMPA receptors in both excitotoxicity and PD, the third class of ionotropic glutamate receptors, kainate receptors, have been less well studied. Given the expression of kainate receptor subunits GluK1-GluK3 in key PD-related brain regions, it has been suggested that GluK1-GluK3 may contribute to excitotoxic cell loss. Therefore the neuroprotective potential of the kainate receptor antagonist UBP310 in animal models of PD was investigated in this study. Stereological quantification revealed administration of UBP310 significantly increased survival of dopaminergic and total neuron populations in the substantia nigra pars compacta in the acute MPTP mouse model of PD. In contrast, UBP310 was unable to rescue MPTP-induced loss of dopamine levels or dopamine transporter expression in the striatum. Furthermore, deletion of GluK1, GluK2 or GluK3 had no effect on MPTP or UBP310-mediated effects across all measures. Interestingly, UBP310 did not attenuate cell loss in the midbrain induced by intrastriatal 6-OHDA toxicity. These results indicate UBP310 provides neuroprotection in the midbrain against MPTP neurotoxicity that is not dependent on specific kainate receptor subunits.
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Affiliation(s)
- Sandy Stayte
- Centre for Neuroscience and Regenerative Medicine, Faculty of Science, University of Technology Sydney, Ultimo, Australia; St Vincent's Centre for Applied Medical Research (AMR), Sydney, Darlinghurst, Australia; Garvan Institute of Medical Research, Darlinghurst, Australia
| | - Kathryn J Laloli
- Centre for Neuroscience and Regenerative Medicine, Faculty of Science, University of Technology Sydney, Ultimo, Australia; St Vincent's Centre for Applied Medical Research (AMR), Sydney, Darlinghurst, Australia
| | - Peggy Rentsch
- Centre for Neuroscience and Regenerative Medicine, Faculty of Science, University of Technology Sydney, Ultimo, Australia; St Vincent's Centre for Applied Medical Research (AMR), Sydney, Darlinghurst, Australia; Garvan Institute of Medical Research, Darlinghurst, Australia
| | - Aimee Lowth
- Garvan Institute of Medical Research, Darlinghurst, Australia
| | - Kong M Li
- Pharmacology Department, Bosch Institute, Sydney Medical School, The University of Sydney, Camperdown, Australia
| | - Russell Pickford
- Bioanalytical Mass Spectrometry Facility, Mark Wainwright Analytical Centre, University of New South Wales, Kensington, Australia
| | - Bryce Vissel
- Centre for Neuroscience and Regenerative Medicine, Faculty of Science, University of Technology Sydney, Ultimo, Australia; St Vincent's Centre for Applied Medical Research (AMR), Sydney, Darlinghurst, Australia; Garvan Institute of Medical Research, Darlinghurst, Australia.
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5
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Affiliation(s)
- Sandy Stayte
- Centre for Neuroscience and Regenerative Medicine, The University of Technology Sydney, Australia
| | - Bryce Vissel
- Centre for Neuroscience and Regenerative Medicine, The University of Technology Sydney, Australia
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Rentsch P, Stayte S, Morris GP, Vissel B. Time dependent degeneration of the nigrostriatal tract in mice with 6-OHDA lesioned medial forebrain bundle and the effect of activin A on L-Dopa induced dyskinesia. BMC Neurosci 2019; 20:5. [PMID: 30760214 PMCID: PMC6374903 DOI: 10.1186/s12868-019-0487-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 02/04/2019] [Indexed: 11/25/2022] Open
Abstract
Background Accurately assessing promising therapeutic interventions for human diseases depends, in part, on the reproducibility of preclinical disease models. With the development of transgenic mice, the rapid adaptation of a 6-OHDA mouse model of Parkinson’s disease that was originally described for the use in rats has come with a lack of a comprehensive characterization of lesion progression. In this study we therefore first characterised the time course of neurodegeneration in the substantia nigra pars compacta and striatum over a 4 week period following 6-OHDA injection into the medial forebrain bundle of mice. We then utilised the model to assess the anti-dyskinetic efficacy of recombinant activin A, a putative neuroprotectant and anti-inflammatory that is endogenously upregulated during the course of Parkinson’s disease. Results We found that degeneration of fibers in the striatum was fully established within 1 week following 6-OHDA administration, but that the loss of neurons continued to progress over time, becoming fully established 3 weeks after the 6-OHDA injection. In assessing the anti-dyskinetic efficacy of activin A using this model we found that treatment with activin A did not significantly reduce the severity, or delay the time-of-onset, of dyskinesia. Conclusion First, the current study concludes that a 3 week duration is required to establish a complete lesion of the nigrostriatal tract following 6-OHDA injection into the medial forebrain bundle of mice. Second, we found that activin A was not anti-dyskinetic in this model. Electronic supplementary material The online version of this article (10.1186/s12868-019-0487-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Peggy Rentsch
- Faculty of Medicine, University of New South Wales, High Street, Sydney, NSW, 2052, Australia.,Centre for Neuroscience and Regenerative Medicine, Faculty of Science, University of Technology Sydney, PO Box 123, Broadway, Sydney, NSW, 2007, Australia.,St. Vincent's Centre for Applied Medical Research (AMR), 405 Liverpool St, Sydney, NSW, 2010, Australia
| | - Sandy Stayte
- Centre for Neuroscience and Regenerative Medicine, Faculty of Science, University of Technology Sydney, PO Box 123, Broadway, Sydney, NSW, 2007, Australia.,St. Vincent's Centre for Applied Medical Research (AMR), 405 Liverpool St, Sydney, NSW, 2010, Australia
| | - Gary P Morris
- Centre for Neuroscience and Regenerative Medicine, Faculty of Science, University of Technology Sydney, PO Box 123, Broadway, Sydney, NSW, 2007, Australia.,St. Vincent's Centre for Applied Medical Research (AMR), 405 Liverpool St, Sydney, NSW, 2010, Australia
| | - Bryce Vissel
- Centre for Neuroscience and Regenerative Medicine, Faculty of Science, University of Technology Sydney, PO Box 123, Broadway, Sydney, NSW, 2007, Australia. .,St. Vincent's Centre for Applied Medical Research (AMR), 405 Liverpool St, Sydney, NSW, 2010, Australia.
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7
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Stayte S, Rentsch P, Tröscher AR, Bamberger M, Li KM, Vissel B. Activin A Inhibits MPTP and LPS-Induced Increases in Inflammatory Cell Populations and Loss of Dopamine Neurons in the Mouse Midbrain In Vivo. PLoS One 2017; 12:e0167211. [PMID: 28121982 PMCID: PMC5266209 DOI: 10.1371/journal.pone.0167211] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 11/10/2016] [Indexed: 01/11/2023] Open
Abstract
Parkinson’s disease is a chronic neurodegenerative disease characterized by a significant loss of dopaminergic neurons within the substantia nigra pars compacta region and a subsequent loss of dopamine within the striatum. A promising avenue of research has been the administration of growth factors to promote the survival of remaining midbrain neurons, although the mechanism by which they provide neuroprotection is not understood. Activin A, a member of the transforming growth factor β superfamily, has been shown to be a potent anti-inflammatory following acute brain injury and has been demonstrated to play a role in the neuroprotection of midbrain neurons against MPP+-induced degeneration in vitro. We hypothesized that activin A may offer similar anti-inflammatory and neuroprotective effects in in vivo mouse models of Parkinson’s disease. We found that activin A significantly attenuated the inflammatory response induced by both MPTP and intranigral administration of lipopolysaccharide in C57BL/6 mice. We found that administration of activin A promoted survival of dopaminergic and total neuron populations in the pars compacta region both 8 days and 8 weeks after MPTP-induced degeneration. Surprisingly, no corresponding protection of striatal dopamine levels was found. Furthermore, activin A failed to protect against loss of striatal dopamine transporter expression in the striatum, suggesting the neuroprotective action of activin A may be localized to the substantia nigra. Together, these results provide the first evidence that activin A exerts potent neuroprotection and anti-inflammatory effects in the MPTP and lipopolysaccharide mouse models of Parkinson’s disease.
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Affiliation(s)
- Sandy Stayte
- Neuroscience Department, Garvan Institute of Medical Research, Sydney, New South Wales, Australia
| | - Peggy Rentsch
- Neuroscience Department, Garvan Institute of Medical Research, Sydney, New South Wales, Australia
| | | | | | - Kong M. Li
- Pharmacology Department, Bosch Institute, Sydney Medical School, The University of Sydney, Sydney, Australia
| | - Bryce Vissel
- Neuroscience Department, Garvan Institute of Medical Research, Sydney, New South Wales, Australia
- School of Life Sciences, University of Technology Sydney, Sydney, Australia
- * E-mail:
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Stayte S, Rentsch P, Li KM, Vissel B. Activin A protects midbrain neurons in the 6-hydroxydopamine mouse model of Parkinson's disease. PLoS One 2015; 10:e0124325. [PMID: 25902062 PMCID: PMC4406584 DOI: 10.1371/journal.pone.0124325] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Accepted: 03/02/2015] [Indexed: 01/11/2023] Open
Abstract
Parkinson’s disease (PD) is a chronic neurodegenerative disease characterized by a significant loss of dopaminergic neurons within the substantia nigra pars compacta (SNpc) and a subsequent loss of dopamine (DA) within the striatum. Despite advances in the development of pharmacological therapies that are effective at alleviating the symptoms of PD, the search for therapeutic treatments that halt or slow the underlying nigral degeneration remains a particular challenge. Activin A, a member of the transforming growth factor β superfamily, has been shown to play a role in the neuroprotection of midbrain neurons against 6-hydroxydopamine (6-OHDA) in vitro, suggesting that activin A may offer similar neuroprotective effects in in vivo models of PD. Using robust stereological methods, we found that intrastriatal injections of 6-OHDA results in a significant loss of both TH positive and NeuN positive populations in the SNpc at 1, 2, and 3 weeks post-lesioning in drug naïve mice. Exogenous application of activin A for 7 days, beginning the day prior to 6-OHDA administration, resulted in a significant survival of both dopaminergic and total neuron numbers in the SNpc against 6-OHDA-induced toxicity. However, we found no corresponding protection of striatal DA or dopamine transporter (DAT) expression levels in animals receiving activin A compared to vehicle controls. These results provide the first evidence that activin A exerts potent neuroprotection in a mouse model of PD, however this neuroprotection may be localized to the midbrain.
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Affiliation(s)
- Sandy Stayte
- Neuroscience Department, Garvan Institute of Medical Research, Sydney, New South Wales, Australia
- Faculty of Medicine, UNSW Australia, Sydney, Australia
| | - Peggy Rentsch
- Neuroscience Department, Garvan Institute of Medical Research, Sydney, New South Wales, Australia
- School of Biotechnology and Biomolecular Sciences, UNSW Australia, Sydney, Australia
| | - Kong M. Li
- Pharmacology Department, Bosch Institute, Sydney Medical School, The University of Sydney, Sydney, Australia
| | - Bryce Vissel
- Neuroscience Department, Garvan Institute of Medical Research, Sydney, New South Wales, Australia
- * E-mail:
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Affiliation(s)
- Sandy Stayte
- Neuroscience, Neurodegenerative Disorders Laboratory, Garvan Institute of Medical ResearchSydney, NSW, Australia
- Faculty of Medicine, University of New South WalesSydney, NSW, Australia
| | - Bryce Vissel
- Neuroscience, Neurodegenerative Disorders Laboratory, Garvan Institute of Medical ResearchSydney, NSW, Australia
- Faculty of Medicine, University of New South WalesSydney, NSW, Australia
- *Correspondence:
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Abstract
Since the 1960's treatments for Parkinson's disease (PD) have traditionally been directed to restore or replace dopamine, with L-Dopa being the gold standard. However, chronic L-Dopa use is associated with debilitating dyskinesias, limiting its effectiveness. This has resulted in extensive efforts to develop new therapies that work in ways other than restoring or replacing dopamine. Here we describe newly emerging non-dopaminergic therapeutic strategies for PD, including drugs targeting adenosine, glutamate, adrenergic, and serotonin receptors, as well as GLP-1 agonists, calcium channel blockers, iron chelators, anti-inflammatories, neurotrophic factors, and gene therapies. We provide a detailed account of their success in animal models and their translation to human clinical trials. We then consider how advances in understanding the mechanisms of PD, genetics, the possibility that PD may consist of multiple disease states, understanding of the etiology of PD in non-dopaminergic regions as well as advances in clinical trial design will be essential for ongoing advances. We conclude that despite the challenges ahead, patients have much cause for optimism that novel therapeutics that offer better disease management and/or which slow disease progression are inevitable.
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Affiliation(s)
- Sandy Stayte
- Neuroscience Department, Neurodegenerative Disorders Laboratory, Garvan Institute of Medical Research, Sydney NSW, Australia ; Faculty of Medicine, University of New South Wales, Sydney NSW, Australia
| | - Bryce Vissel
- Neuroscience Department, Neurodegenerative Disorders Laboratory, Garvan Institute of Medical Research, Sydney NSW, Australia ; Faculty of Medicine, University of New South Wales, Sydney NSW, Australia
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Abdipranoto A, Wu S, Stayte S, Vissel B. The role of neurogenesis in neurodegenerative diseases and its implications for therapeutic development. CNS Neurol Disord Drug Targets 2008; 7:187-210. [PMID: 18537646 DOI: 10.2174/187152708784083858] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Neurodegenerative diseases are characterised by a net loss of neurons from specific regions of the central nervous system (CNS). Until recently, research has focused on identifying mechanisms that lead to neurodegeneration, while therapeutic approaches have been primarily targeted to prevent neuronal loss. This has had limited success and marketed pharmaceuticals do not have dramatic benefits. Here we suggest that the future success of therapeutic strategies will depend on consideration and understanding of the role of neurogenesis in the adult CNS. We summarize evidence suggesting that neurogenesis is impaired in neurodegenerative diseases such as Parkinson's, Alzheimer's and Amyotrophic Lateral Sclerosis, while it is enhanced in stroke. We review studies where stimulation of neurogenesis is associated with restored function in animal models of these diseases, suggesting that neurogenesis is functionally important. We show that many current therapeutics, developed to block degeneration or to provide symptomatic relief, serendipitously stimulate neurogenesis or, at least, do not interfere with it. Importantly, many receptors, ion channels and ligand-gated channels implicated in neurodegeneration, such as NMDA, AMPA, GABA and nicotinic acetylcholine receptors, also play an important role in neurogenesis and regeneration. Therefore, new therapeutics targeted to block degeneration by antagonizing these channels may have limited benefit as they may also block regeneration. Our conclusion is that future drug development must consider neurogenesis. It appears unlikely that drugs being developed to treat neurodegenerative diseases will be beneficial if they impair neurogenesis. And, most tantalizing, therapeutic approaches that stimulate neurogenesis might stimulate repair and even recovery from these devastating diseases.
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Affiliation(s)
- Andrea Abdipranoto
- Neural Plasticity and Regeneration Group, Neuroscience Program, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
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