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Eteläinen TS, Kilpeläinen TP, Ignatius A, Auno S, De Lorenzo F, Uhari-Väänänen JK, Julku UH, Myöhänen TT. Removal of proteinase K resistant αSyn species does not correlate with cell survival in a virus vector-based Parkinson's disease mouse model. Neuropharmacology 2022; 218:109213. [PMID: 35964686 DOI: 10.1016/j.neuropharm.2022.109213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 08/05/2022] [Accepted: 08/07/2022] [Indexed: 10/31/2022]
Abstract
Parkinson's disease (PD) is characterized by degeneration of nigrostriatal dopaminergic neurons and accumulation of α-synuclein (αSyn) as Lewy bodies. Currently, there is no disease-modifying therapy available for PD. We have shown that a small molecular inhibitor for prolyl oligopeptidase (PREP), KYP-2047, relieves αSyn-induced toxicity in various PD models by inducing autophagy and preventing αSyn aggregation. In this study, we wanted to study the effects of PREP inhibition on different αSyn species by using cell culture and in vivo models. We used Neuro2A cells with transient αSyn overexpression and oxidative stress or proteasomal inhibition-induced αSyn aggregation to assess the effect of KYP-2047 on soluble αSyn oligomers and on cell viability. Here, the levels of soluble αSyn were measured by using ELISA, and the impact of KYP-2047 was compared to anle138b, nilotinib and deferiprone. To evaluate the effect of KYP-2047 on αSyn fibrillization in vivo, we used unilateral nigral AAV1/2-A53T-αSyn mouse model, where the KYP-2047 treatment was initiated two- or four-weeks post injection. KYP-2047 and anle138b protected cells from αSyn toxicity but interestingly, KYP-2047 did not reduce soluble αSyn oligomers. In AAV-A53T-αSyn mouse model, KYP-2047 reduced significantly proteinase K-resistant αSyn oligomers and oxidative damage related to αSyn aggregation. However, the KYP-2047 treatment that was initiated at the time of symptom onset, failed to protect the nigrostriatal dopaminergic neurons. Our results emphasize the importance of whole αSyn aggregation process in the pathology of PD and raise an important question about the forms of αSyn that are reasonable targets for PD drug therapy.
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Affiliation(s)
- Tony S Eteläinen
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Finland
| | - Tommi P Kilpeläinen
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Finland
| | - Adele Ignatius
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Finland
| | - Samuli Auno
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Finland
| | - Francesca De Lorenzo
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Finland
| | - Johanna K Uhari-Väänänen
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Finland
| | - Ulrika H Julku
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Finland
| | - Timo T Myöhänen
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Finland; School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Finland.
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Myöhänen TT, Mertens F, Norrbacka S, Cui H. Deletion or inhibition of prolyl oligopeptidase blocks lithium-induced phosphorylation of GSK3b and Akt by activation of protein phosphatase 2A. Basic Clin Pharmacol Toxicol 2021; 129:287-296. [PMID: 34196102 DOI: 10.1111/bcpt.13632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 06/15/2021] [Accepted: 06/27/2021] [Indexed: 11/27/2022]
Abstract
Alterations in prolyl oligopeptidase (PREP) activity have been connected, for example, with bipolar and major depressive disorder, and several studies have reported that lack or inhibition of PREP blocks the effects of lithium on inositol 1,4,5-triphosphate (IP3 ) levels. However, the impact of PREP modulation on other intracellular targets of lithium, such as glycogen synthase kinase 3 beta (GSK3b) or protein kinase B (Akt), has not been studied. We recently found that PREP regulates protein phosphatase 2A (PP2A), and because GSK3b and Akt are PP2A substrates, we studied if PREP-related lithium insensitivity is dependent on PP2A. To assess this, HEK-293 and SH-SY5Y cells with PREP deletion or PREP inhibition (KYP-2047) were exposed to lithium, and thereafter, the phosphorylation levels of GSK3b and Akt were measured by Western blot. As expected, PREP deletion and inhibition blocked the lithium-induced phosphorylation on GSK3b and Akt in both cell lines. When lithium exposure was combined with okadaic acid, a PP2A inhibitor, KYP-2047 did not have effect on lithium-induced GSK3b and Akt phosphorylation. Therefore, we conclude that PREP deletion or inhibition blocks the intracellular effects of lithium on GSK3b and Akt via PP2A activation.
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Affiliation(s)
- Timo T Myöhänen
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, University of Helsinki, Helsinki, Finland.,Integrative Physiology and Pharmacology Unit, Institute of Biomedicine, University of Turku, Turku, Finland.,School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland
| | - Freke Mertens
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, University of Helsinki, Helsinki, Finland
| | - Susanna Norrbacka
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, University of Helsinki, Helsinki, Finland
| | - Hengjing Cui
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, University of Helsinki, Helsinki, Finland.,Department of Pharmacy, Ruijin hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
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Julku UH, Jäntti M, Svarcbahs R, Myöhänen TT. Prolyl Oligopeptidase Regulates Dopamine Transporter Oligomerization and Phosphorylation in a PKC- and ERK-Independent Manner. Int J Mol Sci 2021; 22:1777. [PMID: 33579026 PMCID: PMC7916783 DOI: 10.3390/ijms22041777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/04/2021] [Accepted: 02/05/2021] [Indexed: 12/18/2022] Open
Abstract
Prolyl oligopeptidase (PREP) is a serine protease that binds to alpha-synuclein (aSyn) and induces its aggregation. PREP inhibitors have been shown to have beneficial effects in Parkinson's disease models by enhancing the clearance of aSyn aggregates and modulating striatal dopamine. Additionally, we have shown that PREP regulates phosphorylation and internalization of dopamine transporter (DAT) in mice. In this study, we clarified the mechanism behind this by using HEK-293 and PREP knock-out HEK-293 cells with DAT transfection. We tested the effects of PREP, PREP inhibition, and alpha-synuclein on PREP-related DAT regulation by using Western blot analysis and a dopamine uptake assay, and characterized the impact of PREP on protein kinase C (PKC) and extracellular signal-regulated kinase (ERK) by using PKC assay and Western blot, respectively, as these kinases regulate DAT phosphorylation. Our results confirmed our previous findings that a lack of PREP can increase phosphorylation and internalization of DAT and decrease uptake of dopamine. PREP inhibition had a variable impact on phosphorylation of ERK dependent on the metabolic state of cells, but did not have an effect on phosphorylation or function of DAT. PREP modifications did not affect PKC activity either. Additionally, a lack of PREP elevated a DAT oligomerization that is associated with intracellular trafficking of DAT. Our results suggest that PREP-mediated phosphorylation, oligomerization, and internalization of DAT is not dependent on PKC or ERK.
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Affiliation(s)
- Ulrika H. Julku
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Viikinkaari 5E (P.O. Box 56), FI-00014 Helsinki, Finland; (U.H.J.); (M.J.); (R.S.)
| | - Maria Jäntti
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Viikinkaari 5E (P.O. Box 56), FI-00014 Helsinki, Finland; (U.H.J.); (M.J.); (R.S.)
| | - Reinis Svarcbahs
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Viikinkaari 5E (P.O. Box 56), FI-00014 Helsinki, Finland; (U.H.J.); (M.J.); (R.S.)
| | - Timo T. Myöhänen
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Viikinkaari 5E (P.O. Box 56), FI-00014 Helsinki, Finland; (U.H.J.); (M.J.); (R.S.)
- Integrative Physiology and Pharmacology Unit/Institute of Biomedicine, Faculty of Medicine, University of Turku, FI-20520 Turku, Finland
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Tian L, Qian W, Qian Q, Zhang W, Cai X. Gingerol inhibits cisplatin-induced acute and delayed emesis in rats and minks by regulating the central and peripheral 5-HT, SP, and DA systems. J Nat Med 2019; 74:353-370. [PMID: 31768887 PMCID: PMC7044144 DOI: 10.1007/s11418-019-01372-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Accepted: 11/12/2019] [Indexed: 12/14/2022]
Abstract
Abstract Gingerol, a biologically active component in ginger, has shown antiemetic properties. Our study aimed to explore the underlying mechanisms of gingerol on protecting rats and minks from chemotherapy-induced nausea and vomiting. The preventive impact of gingerol was evaluated in the pica model of rats and the vomiting model of minks induced by cisplatin at every 6 h continuously for a duration of 72 h. Animals were arbitrarily separated into blank control group, simple gingerol control group, cisplatin control group, cisplatin + metoclopramide group, cisplatin + three different doses gingerol group (low-dose; middle-dose; high-dose). The area postrema as well as ileum damage were assessed using H&E stain. The levels of 5-TH, 5-HT3 receptor, TPH, SERT, SP, NK1 receptor, PPT, NEP, DA, D2R, TH, and DAT were determined using immunohistochemistry or qRT-PCR in rats and minks. All indicators were measured in the area postrema along with ileum. The kaolin intake by rats and the incidence of CINV of minks were significantly decreased after pretreatment with gingerol in a dosage-dependent way for the duration of 0–24-h and 24–72-h. Gingerol markedly decreased the levels of 5-TH, 5-HT3 receptor, TPH, SP, NK1 receptor, PPT, DA, D2R, TH, alleviated area postrema as well as ileum damage, and increased the accumulation of SERT, NEP, DAT in the area postrema along with ileum of rats and minks. Gingerol alleviates cisplatin-induced kaolin intake of rats and emesis of minks possibly by regulating central and peripheral 5-HT system, SP system and DA system. Graphic abstract ![]()
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Affiliation(s)
- Li Tian
- First Clinical Medical College, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, People's Republic of China
| | - Weibin Qian
- Postdoctoral Mobile Station, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, People's Republic of China.,Department of Lung Disease, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, No. 16369 Jingshi Road, Lixia District, Jinan, Shandong, People's Republic of China
| | - Qiuhai Qian
- Department of Endocrinology, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, People's Republic of China
| | - Wei Zhang
- Department of Lung Disease, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, No. 16369 Jingshi Road, Lixia District, Jinan, Shandong, People's Republic of China.
| | - Xinrui Cai
- Department of Traditional Chinese Medicine, Shandong Academy of Occupational Health and Occupational Medicine, Shandong First Medical University and Shandong Academy of Medical Sciences, No. 17 Yuxing Road, Central District, Jinan, Shandong, People's Republic of China.
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Behavioural and dopaminergic changes in double mutated human A30P*A53T alpha-synuclein transgenic mouse model of Parkinson´s disease. Sci Rep 2019; 9:17382. [PMID: 31758049 PMCID: PMC6874660 DOI: 10.1038/s41598-019-54034-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 11/08/2019] [Indexed: 12/23/2022] Open
Abstract
Alpha-synuclein (aSyn) is the main component of Lewy bodies, the histopathological marker in Parkinson’s disease (PD), and point mutations and multiplications of the aSyn coding SNCA gene correlate with early onset PD. Therefore, various transgenic mouse models overexpressing native or point-mutated aSyn have been developed. Although these models show highly increased aSyn expression they rarely capture dopaminergic cell loss and show a behavioural phenotype only at old age, whereas SNCA mutations are risk factors for PD with earlier onset. The aim of our study was to re-characterize a transgenic mouse strain carrying both A30P and A53T mutated human aSyn. Our study revealed decreased locomotor activity for homozygous transgenic mice starting from 3 months of age which was different from previous studies with this mouse strain that had behavioural deficits starting only after 7–9 months. Additionally, we found a decreased amphetamine response in locomotor activity and decreased extracellular dopaminergic markers in the striatum and substantia nigra with significantly elevated levels of aSyn oligomers. In conclusion, homozygous transgenic A30P*A53T aSyn mice capture several phenotypes of PD with early onset and could be a useful tool for aSyn studies.
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Svarcbahs R, Jäntti M, Kilpeläinen T, Julku UH, Urvas L, Kivioja S, Norrbacka S, Myöhänen TT. Prolyl oligopeptidase inhibition activates autophagy via protein phosphatase 2A. Pharmacol Res 2019; 151:104558. [PMID: 31759088 DOI: 10.1016/j.phrs.2019.104558] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 11/02/2019] [Accepted: 11/19/2019] [Indexed: 02/06/2023]
Abstract
Prolyl oligopeptidase (PREP) is a serine protease that has been studied particularly in the context of neurodegenerative diseases for decades but its physiological function has remained unclear. We have previously found that PREP negatively regulates beclin1-mediated macroautophagy (autophagy), and that PREP inhibition by a small-molecule inhibitor induces clearance of protein aggregates in Parkinson's disease models. Since autophagy induction has been suggested as a potential therapy for several diseases, we wanted to further characterize how PREP regulates autophagy. We measured the levels of various kinases and proteins regulating beclin1-autophagy in HEK-293 and SH-SY5Y cell cultures after PREP inhibition, PREP deletion, and PREP overexpression and restoration, and verified the results in vivo by using PREP knock-out and wild-type mouse tissue where PREP was restored or overexpressed, respectively. We found that PREP regulates autophagy by interacting with protein phosphatase 2A (PP2A) and its endogenous inhibitor, protein phosphatase methylesterase 1 (PME1), and activator (protein phosphatase 2 phosphatase activator, PTPA), thus adjusting its activity and the levels of PP2A in the intracellular pool. PREP inhibition and deletion increased PP2A activity, leading to activation of death-associated protein kinase 1 (DAPK1), beclin1 phosphorylation and induced autophagy while PREP overexpression reduced this. Lowered activity of PP2A is connected to several neurodegenerative disorders and cancers, and PP2A activators would have enormous potential as drug therapy but development of such compounds has been a challenge. The concept of PREP inhibition has been proved safe, and therefore, our study supports the further development of PREP inhibitors as PP2A activators.
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Affiliation(s)
- Reinis Svarcbahs
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland
| | - Maria Jäntti
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland
| | - Tommi Kilpeläinen
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland
| | - Ulrika H Julku
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland
| | - Lauri Urvas
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland
| | - Saara Kivioja
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland
| | - Susanna Norrbacka
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland
| | - Timo T Myöhänen
- Division of Pharmacology and Pharmacotherapy/Drug Research Program, Faculty of Pharmacy, University of Helsinki, Finland.
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Ali I, Van Eetveldt A, Van Elzen R, Kalathil Raju T, Van Der Veken P, Lambeir A, Dedeurwaerdere S. Spatiotemporal expression and inhibition of prolyl oligopeptidase contradict its involvement in key pathologic mechanisms of kainic acid-induced temporal lobe epilepsy in rats. Epilepsia Open 2019; 4:92-101. [PMID: 30868119 PMCID: PMC6398098 DOI: 10.1002/epi4.12293] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 12/04/2018] [Indexed: 11/06/2022] Open
Abstract
OBJECTIVE Prolyl oligopeptidase (PREP) has been implicated in neuroinflammatory processes and neuroplasticity and has been suggested as a target for the treatment of neurodegenerative disease. The aim of this investigation was to explore the involvement of PREP in the neuropathologic mechanisms relevant to temporal lobe epilepsy (TLE) using a PREP inhibitor in a well-established rat model. METHODS PREP activity and expression was studied in Sprague-Dawley rats 2 and 12 weeks following kainic acid-induced status epilepticus (KASE). Continuous video-electroencephalography monitoring was performed for 2 weeks in the 12-week cohort to identify a relationship of PREP expression/activity with epileptic seizures. In addition, the animals included in the 2-week time point were treated with a specific inhibitor of PREP, KYP-2047, or saline continuously, starting immediately after SE. PREP activity and its expression were analyzed in rat brain by using enzyme kinetics and western blot. In addition, markers for microglial activation, astrogliosis, cell loss, and cell proliferation were evaluated. RESULTS Enzymatic activity of PREP was unchanged following induction of SE after 2 and 12 weeks in rats. PREP activity in epileptic rats did not relate to the number of seizures/day at the 12-week time point. Moreover, continuous inhibition of PREP for 2 weeks after KASE did not alter the SE-mediated neuroinflammatory response, cell loss, or cell proliferation in the hippocampal subgranule zone measured at the 2-week time point. SIGNIFICANCE PREP inhibition does not affect key pathologic mechanisms, including activation of glial cells, cell loss, and neural progenitor cell proliferation, in this KASE model of TLE. The results do not support a direct role of PREP in seizure burden during the chronic epilepsy period in this model.
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Affiliation(s)
- Idrish Ali
- Department of Translational NeurosciencesUniversity of AntwerpWilrijkBelgium
- Present address:
Department of MedicineUniversity of MelbourneMelbourneAustralia
| | | | - Roos Van Elzen
- Laboratory of Medical BiochemistryUniversity of AntwerpWilrijkBelgium
| | - Tom Kalathil Raju
- Laboratory of Medical BiochemistryUniversity of AntwerpWilrijkBelgium
| | | | | | - Stefanie Dedeurwaerdere
- Laboratory of Experimental Hematology, VaxinfectioUniversity of AntwerpAntwerpBelgium
- Present address:
UCB PharmaBraine‐l'AlleudBelgium
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New tricks of prolyl oligopeptidase inhibitors - A common drug therapy for several neurodegenerative diseases. Biochem Pharmacol 2019; 161:113-120. [PMID: 30660495 DOI: 10.1016/j.bcp.2019.01.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 01/15/2019] [Indexed: 12/14/2022]
Abstract
Changes in prolyl oligopeptidase (PREP) expression levels, protein distribution, and activity correlate with aging and are reported in many neurodegenerative conditions. Together with decreased neuropeptide levels observed in aging and neurodegeneration, and PREP's ability to cleave only small peptides, PREP was identified as a druggable target. Known PREP non-enzymatic functions were disregarded or attributed to PREP enzymatic activity, and several potent small molecule PREP inhibitors were developed during early stages of PREP research. These showed a lot of potential but with variable results in experimental memory models, however, the initial excitement was short-lived and all of the clinical trials were discontinued in either Phase I or II clinical trials for unknown reasons. Recently, PREP's ability to form protein-protein interactions, alter cell proliferation and autophagy has gained more attention than earlier recognized catalytical activity. Of new findings, particularly the aggregation of alpha-synuclein (aSyn) that is seen in the presence of PREP is especially interesting because PREP inhibitors are capable of altering aSyn-PREP interaction in a manner that reduces the aSyn dimerization process. Therefore, it is possible that PREP inhibitors that are altering interactions could have different characteristics than those aimed for strong inhibition of catalytic activity. Moreover, PREP co-localization with aSyn, tau, and amyloid-beta hints to PREP's possible role not only in the synucleinopathies but in other neurodegenerative diseases as well. This commentary will focus on less well-acknowledged non-enzymatic functions of PREP that may provide a better approach for the development of PREP inhibitors for the treatment of neurodegenerative disorders.
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Leino S, Kohtala S, Rantamäki T, Koski SK, Rannanpää S, Salminen O. Dyskinesia and brain-derived neurotrophic factor levels after long-term levodopa and nicotinic receptor agonist treatments in female mice with near-total unilateral dopaminergic denervation. BMC Neurosci 2018; 19:77. [PMID: 30497382 PMCID: PMC6267795 DOI: 10.1186/s12868-018-0478-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Accepted: 11/27/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The treatment of Parkinson's disease is often complicated by levodopa-induced dyskinesia (LID). Nicotinic acetylcholine receptor agonists can alleviate LID in animal models but may be less effective in conditions of severe dopaminergic denervation. While the mechanisms of LID remain incompletely understood, elevated corticostriatal levels of the brain-derived neurotrophic factor (BDNF) have been suggested to play a role. Here, female mice with near-total unilateral 6-hydroxydopamine-induced nigrostriatal lesions were chronically treated with levodopa, and the effects of the α7 nicotinic receptor partial agonist AZD0328 and nicotine on LID were assessed. At the end of the experiment, BDNF protein levels in the prefrontal cortex and striatum were measured. RESULTS Five-day treatments with three escalating doses of AZD0328 and a 10-week treatment with nicotine failed to alleviate LID. BDNF levels in the lesioned striatum correlated positively with LID severity, but no evidence was found for a levodopa-induced elevation of corticostriatal BDNF in the lesioned hemisphere. The nicotine treatment decreased BDNF levels in the prefrontal cortex but had no effect on striatal BDNF. CONCLUSIONS The findings suggest that treatment of LID with nicotinic agonists may lose its effectiveness as the disease progresses, represent further evidence for a role for BDNF in LID, and expand previous knowledge on the effects of long-term nicotine treatment on BDNF.
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Affiliation(s)
- Sakari Leino
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, 00014, Helsinki, Finland
| | - Samuel Kohtala
- Laboratory of Neurotherapeutics, Division of Physiology and Neuroscience, Department of Biosciences, University of Helsinki, 00014, Helsinki, Finland
| | - Tomi Rantamäki
- Laboratory of Neurotherapeutics, Division of Physiology and Neuroscience, Department of Biosciences, University of Helsinki, 00014, Helsinki, Finland
| | - Sini K Koski
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, 00014, Helsinki, Finland
| | - Saara Rannanpää
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, 00014, Helsinki, Finland
| | - Outi Salminen
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, 00014, Helsinki, Finland.
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Attenuated dopaminergic neurodegeneration and motor dysfunction in hemiparkinsonian mice lacking the α5 nicotinic acetylcholine receptor subunit. Neuropharmacology 2018; 138:371-380. [PMID: 29940207 DOI: 10.1016/j.neuropharm.2018.06.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 06/04/2018] [Accepted: 06/21/2018] [Indexed: 11/23/2022]
Abstract
Preclinical studies suggest the involvement of various subtypes of nicotinic acetylcholine receptors in the pathophysiology of Parkinson's disease, a neurodegenerative disorder characterized by the death of dopaminergic neurons in the substantia nigra pars compacta (SNC). We studied for the first time the effects of α5 nicotinic receptor subunit gene deletion on motor behavior and neurodegeneration in mouse models of Parkinson's disease and levodopa-induced dyskinesia. Unilateral dopaminergic lesions were induced in wild-type and α5-KO mice by 6-hydroxydopamine injections into the striatum or the medial forebrain bundle. Subsequently, rotational behavior induced by dopaminergic drugs was measured. A subset of animals received chronic treatments with levodopa and nicotine to assess levodopa-induced dyskinesia and antidyskinetic effects by nicotine. SNC lesion extent was assessed with tyrosine hydroxylase immunohistochemistry and stereological cell counting. Effects of α5 gene deletion on the dopaminergic system were investigated by measuring ex vivo striatal dopamine transporter function and protein expression, dopamine and metabolite tissue concentrations and dopamine receptor mRNA expression. Hemiparkinsonian α5-KO mice exhibited attenuated rotational behavior after amphetamine injection and attenuated levodopa-induced dyskinesia. In the intrastriatal lesion model, dopaminergic cell loss in the medial cluster of the SNC was less severe in α5-KO mice. Decreased striatal dopamine uptake in α5-KO animals suggested reduced dopamine transporter function as a mechanism of attenuated neurotoxicity. Nicotine reduced dyskinesia severity in wild-type but not α5-KO mice. The attenuated dopaminergic neurodegeneration and motor dysfunction observed in hemiparkinsonian α5-KO mice suggests potential for α5 subunit-containing nicotinic receptors as a novel target in the treatment of Parkinson's disease.
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Svarcbahs R, Julku UH, Norrbacka S, Myöhänen TT. Removal of prolyl oligopeptidase reduces alpha-synuclein toxicity in cells and in vivo. Sci Rep 2018; 8:1552. [PMID: 29367610 PMCID: PMC5784134 DOI: 10.1038/s41598-018-19823-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 01/09/2018] [Indexed: 01/09/2023] Open
Abstract
Prolyl oligopeptidase (PREP) inhibition by small-molecule inhibitors can reduce alpha-synuclein (aSyn) aggregation, a key player in Parkinson's disease pathology. However, the significance of PREP protein for aSyn aggregation and toxicity is not known. We studied this in vivo by using PREP knock-out mice with viral vector injections of aSyn and PREP. Animal behavior was studied by locomotor activity and cylinder tests, microdialysis and HPLC were used to analyze dopamine levels, and different aSyn forms and loss of dopaminergic neurons were studied by immunostainings. Additionally, PREP knock-out cells were used to characterize the impact of PREP and aSyn on autophagy, proteasomal system and aSyn secretion. PREP knock-out animals were nonresponsive to aSyn-induced unilateral toxicity but combination of PREP and aSyn injections increased aSyn toxicity. Phosphorylated p129, proteinase K resistant aSyn levels and tyrosine hydroxylase positive cells were decreased in aSyn and PREP injected knock-out animals. These changes were accompanied by altered dopamine metabolite levels. PREP knock-out cells showed reduced response to aSyn, while cells were restored to wild-type cell levels after PREP overexpression. Taken together, our data suggests that PREP can enhance aSyn toxicity in vivo.
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Affiliation(s)
- Reinis Svarcbahs
- Division of Pharmacology and Pharmacotherapy, University of Helsinki, Viikinkaari 5E, P.O. Box 56, 00014, Helsinki, Finland
| | - Ulrika H Julku
- Division of Pharmacology and Pharmacotherapy, University of Helsinki, Viikinkaari 5E, P.O. Box 56, 00014, Helsinki, Finland
| | - Susanna Norrbacka
- Division of Pharmacology and Pharmacotherapy, University of Helsinki, Viikinkaari 5E, P.O. Box 56, 00014, Helsinki, Finland
| | - Timo T Myöhänen
- Division of Pharmacology and Pharmacotherapy, University of Helsinki, Viikinkaari 5E, P.O. Box 56, 00014, Helsinki, Finland.
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Männistö PT, García-Horsman JA. Mechanism of Action of Prolyl Oligopeptidase (PREP) in Degenerative Brain Diseases: Has Peptidase Activity Only a Modulatory Role on the Interactions of PREP with Proteins? Front Aging Neurosci 2017; 9:27. [PMID: 28261087 PMCID: PMC5306367 DOI: 10.3389/fnagi.2017.00027] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 01/30/2017] [Indexed: 12/14/2022] Open
Abstract
In the aging brain, the correct balance of neural transmission and its regulation is of particular significance, and neuropeptides have a significant role. Prolyl oligopeptidase (PREP) is a protein highly expressed in brain, and evidence indicates that it is related to aging and in neurodegenration. Although PREP is regarded as a peptidase, the physiological substrates in the brain have not been defined, and after intense research, the molecular mechanisms where this protein is involved have not been defined. We propose that PREP functions as a regulator of other proteins though peptide gated direct interaction. We speculate that, at least in some processes where PREP has shown to be relevant, the peptidase activity is only a consequence of the interactions, and not the main physiological activity.
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Affiliation(s)
- Pekka T Männistö
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki Helsinki, Finland
| | - J Arturo García-Horsman
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki Helsinki, Finland
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