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van Onselen R, Kennedy C, Downing TG. Protection against β-N-methylamino-l-alanineꟷinduced vesicular monoamine transporter 2 inhibition by hydroxyl-containing proteinogenic amino acids. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2024; 107:104399. [PMID: 38403141 DOI: 10.1016/j.etap.2024.104399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 02/02/2024] [Accepted: 02/21/2024] [Indexed: 02/27/2024]
Abstract
β-N-methylamino-l-alanine (BMAA) has been shown to inhibit vesicular monoamine transporter 2 (VMAT2), thereby preventing the uptake of monoaminergic neurotransmitters into platelet dense granules and synaptic vesicles. The inhibition is hypothesized to be through direct association of BMAA with hydroxyl groupꟷcontaining amino acid residues in VMAT2. This study evaluated whether BMAA-induced inhibition of VMAT2 could be prevented directly by co-incubation of BMAA with amino acids, and if this protection was specific for BMAA inhibition of VMAT2. l-tyrosine, and to a lesser extent l-serine, was able to prevent BMAA-induced VMAT2 inhibition in a concentration-dependent manner, whereas neither l-threonine nor amino acids without side chain hydroxyl groups could reduce this inhibition. Reserpine-induced VMAT2 inhibition was unaffected by any of the amino acids. These data support the hypothesized interaction between BMAA and hydroxyl groupꟷcontaining amino acids and suggests that this interaction might be leveraged to protect against the toxicity of BMAA.
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Affiliation(s)
- Rianita van Onselen
- Biomedical Research and Innovation Platform, South African Medical Research Council, Cape Town, South Africa; Department of Biochemistry and Microbiology, Nelson Mandela University, Gqeberha, South Africa.
| | - Chanté Kennedy
- Department of Biochemistry and Microbiology, Nelson Mandela University, Gqeberha, South Africa.
| | - Tim G Downing
- Department of Biochemistry and Microbiology, Nelson Mandela University, Gqeberha, South Africa.
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Luo Y, Zheng M, Su Z, Cai C, Li X. Transcriptome profile of reserpine-induced locomotor behavioral changes in zebrafish (Danio rerio). Prog Neuropsychopharmacol Biol Psychiatry 2024; 129:110874. [PMID: 37839537 DOI: 10.1016/j.pnpbp.2023.110874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 09/26/2023] [Accepted: 10/11/2023] [Indexed: 10/17/2023]
Abstract
Reserpine is a drug that is commonly used as an antihypertensive and antipsychotic drug in clinical practice. During our previous research, we found that reserpine treatment in zebrafish larvae can cause depression-like behaviors, but the corresponding mechanisms are still unclear. In this study, we aimed to investigate the molecular mechanism by which reserpine exposure affects locomotor behaviors in larval zebrafish through transcriptome analysis. The gene enrichment results showed that the differentially highly expressed genes of zebrafish are mainly enriched in voltage-gated ion channels, dopaminergic synapses and wnt signaling pathways. Selected genes (apc2, cacna1aa, drd2b, dvl1a, fzd1, wnt1, wnt3a, wnt9a and wnt10a) by transcriptomic results was validated by real-time PCR. Consistently, Wnt signaling pathway inhibitor XAV939 may induce reduced behavioral changes in zebrafish larvae, while the Wnt signaling pathway agonist SB415286 reversed the reserpine-induced depressive effects. Our study provides gene transcriptional profile data for future research on reserpine-induced locomotor behavioral changes.
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Affiliation(s)
- Yacan Luo
- Department of Respiratory & Critical Care Medicine, YueYang People' s Hospital, Yueyang, Hunan 414000, People's Republic of China; Zhejiang Clinical Research Center for Mental Disorders, The Affiliated Kangning Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, China
| | - Miaomiao Zheng
- Zhejiang Clinical Research Center for Mental Disorders, The Affiliated Kangning Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, China
| | - Zhengkang Su
- Zhejiang Clinical Research Center for Mental Disorders, The Affiliated Kangning Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, China
| | - Chang Cai
- The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, People's Republic of China
| | - Xi Li
- Zhejiang Clinical Research Center for Mental Disorders, The Affiliated Kangning Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, China.
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van Onselen R, Downing TG. Uptake of β-N-methylamino-L-alanine (BMAA) into glutamate-specific synaptic vesicles: Exploring the validity of the excitotoxicity mechanism of BMAA. Neurosci Lett 2024; 821:137593. [PMID: 38103629 DOI: 10.1016/j.neulet.2023.137593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 12/01/2023] [Accepted: 12/07/2023] [Indexed: 12/19/2023]
Abstract
The first mechanism of toxicity proposed for the cyanobacterial neurotoxin β-N-methylamino-L-alanine (BMAA) was excitotoxicity, and this was supported by numerous in vitro studies in which overactivation of both ionotropic and metabotropic glutamate receptors was reported. However, the excitotoxicity of BMAA is weak in comparison with other known excitotoxins and on par with that of glutamate, implying that to achieve sufficient synaptic concentrations of BMAA to cause classical in vivo excitotoxicity, BMAA must either accumulate in synapses to allow persistent glutamate receptor activation or it must be released in sufficiently high concentrations into synapses to cause the overexcitation. Since it has been shown that BMAA can be readily removed from synapses, release of high concentrations of BMAA into synapses must be shown to confirm its role as an excitotoxin in in vivo systems. This study therefore sought to evaluate the uptake of BMAA into synaptic vesicles and to determine if BMAA affects the uptake of glutamate into synaptic vesicles. There was no evidence to support uptake of BMAA into glutamate-specific synaptic vesicles but there was some indication that BMAA may affect the uptake of glutamate into synaptic vesicles. The uptake of BMAA into synaptic vesicles isolated from areas other than the cerebral cortex should be investigated before definite conclusions can be drawn about the role of BMAA as an excitotoxin.
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Affiliation(s)
- Rianita van Onselen
- Biomedical Research and Innovation Platform, South African Medical Research Council, Cape Town, South Africa; Department of Biochemistry and Microbiology, Nelson Mandela University, Gqeberha, South Africa
| | - Tim G Downing
- Department of Biochemistry and Microbiology, Nelson Mandela University, Gqeberha, South Africa.
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Tian S, Zheng H, Wu L, Wu W. Factors influencing short-term prognosis after botulinum toxin type A treatment for hemifacial spasm:A retrospective study. Heliyon 2024; 10:e24898. [PMID: 38312606 PMCID: PMC10835370 DOI: 10.1016/j.heliyon.2024.e24898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 12/17/2023] [Accepted: 01/16/2024] [Indexed: 02/06/2024] Open
Abstract
Background It is widely acknowledged that botulinum toxin type A (BTX-A) has been widely used in the treatment of hemifacial spasm (HFS). However, there is currently a lack of systematic analysis of the factors affecting its therapeutic effect. Therefore, this study aims to explore the influencing factors of BTX-A in the treatment of HFS and to identify risk factors for poor prognosis. Methods Retrospective study including 118 patients with HFS treated with BTX-A from 2019 January to 2023 April. Demographic and etiological variables as well as doses, number of sessions of BTX-A, infiltrated muscles, therapeutic response according to the Cohen evaluation scale, and side effects were analyzed. Logistic regression analysis was performed to identify the factors that are associated with the short-term prognosis of BTX-A for the treatment of HFS. Results Among the 118 patients with HFS included in this study, 57 achieved complete relief, 51 had significant relief, 7 had partial relief, and no improvement was observed in 3. The overall effective rate was 91.53 %. Results from the univariate analysis indicated that male, drinking, diabetes, and hypertension were all associated with poor short-term prognosis of BTX-A in the treatment of HFS. Multivariable logistic regression analysis further revealed that hypertension was an independent risk factor for poor short-term prognosis following BTX-A treatment for HFS (OR=5.847, P<0.05). Conclusion BTX-A was effective in treating HFS and had minimal adverse effects. Hypertension was an independent risk factor for poor short-term prognosis following BTX-A treatment of HFS.
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Affiliation(s)
- Sheng Tian
- Department of Neurology, The Second Affiliated Hospital, Jiangxi Medical College, Nanchang University, China
| | - Heqing Zheng
- Department of Neurology, The Second Affiliated Hospital, Jiangxi Medical College, Nanchang University, China
| | - Lanxiang Wu
- Department of Neurology, The Second Affiliated Hospital, Jiangxi Medical College, Nanchang University, China
| | - Wei Wu
- Department of Neurology, The Second Affiliated Hospital, Jiangxi Medical College, Nanchang University, China
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Yan X, Song X, Chen W, Jia Y, Gao J, Wang X, Qin L, Xue R, Song G. Frizzled 6 mutation regulates reserpine-induced depression-like behavior and Wnt signaling pathway in mice. Eur J Pharmacol 2023; 957:175996. [PMID: 37597646 DOI: 10.1016/j.ejphar.2023.175996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 07/14/2023] [Accepted: 08/10/2023] [Indexed: 08/21/2023]
Abstract
BACKGROUND Frizzled 6 (Fzd6) is involved in the development of various disorders; however, its role in the etiology of depression remains unclear. We aimed to determine the potential regulatory mechanisms of Fzd6 as a Wnt receptor in depression. METHODS Mice were divided into four groups: wild-type control (Fzd6WT-control), Fzd6 mutant control (Fzd6Q152E-control), wild-type reserpine (Fzd6WT-reserpine), and Fzd6 mutant reserpine (Fzd6Q152E-reserpine). Reserpine (0.5 mg/kg) was injected intraperitoneally for 10 days. Four behavioral experiments were performed to assess the effects of Fzd6Q152E on depression-like behaviors in the reserpine-treated mice. Blood samples were collected for an enzyme-linked immunosorbent assay (ELISA). Gene expression in the hippocampus was quantified using quantitative real-time polymerase chain reaction (qRT-PCR), and protein expression levels in the hippocampus were identified using western blotting. RESULTS The Fzd6 mutation affected reserpine-induced depression-like behavioral changes in mice. ELISA revealed significantly reduced serum levels of 5-hydroxytryptamine (5-HT), brain-derived neurotrophic factor (BDNF), and norepinephrine in both Fzd6Q152E-reserpine and Fzd6WT-reserpine mice, with a more pronounced decrease in Fzd6Q152E-reserpine mice, especially in norepinephrine expression. The qRT-PCR results showed significantly decreased Fzd6 expression in Fzd6Q152E-reserpine mice and altered expression of Dkk2, Gsk-3β, Lrp6, Wnt2, Wnt3, and Wnt3a in the Wnt pathway. Western blotting revealed decreased Fzd6 protein expression in Fzd6Q152E-control mice compared to Fzd6WT-control mice, whereas Fzd6 protein expression was restored in Fzd6Q152E-reserpine mice, and Gsk-3β expression was significantly changed. CONCLUSION Fzd6 potentially influences reserpine-induced depressive behavioral changes and serum depressive factor alterations and modulates the expression of the Wnt signaling pathway in the hippocampus of depressed mice.
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Affiliation(s)
- Xiaoru Yan
- Laboratory Animal Center, Shanxi Key Laboratory of Experimental Animal Science and Human Disease Animal Model, Shanxi Medical University, Road Xinjian 56, Taiyuan, Shanxi, 030001, China; School of Basic Medicine, Shanxi Medical University, Road Xinjian 56, Taiyuan, Shanxi, 030001, China
| | - Xiaona Song
- School of Basic Medicine, Shanxi Medical University, Road Xinjian 56, Taiyuan, Shanxi, 030001, China
| | - Wenlu Chen
- Laboratory Animal Center, Shanxi Key Laboratory of Experimental Animal Science and Human Disease Animal Model, Shanxi Medical University, Road Xinjian 56, Taiyuan, Shanxi, 030001, China; School of Basic Medicine, Shanxi Medical University, Road Xinjian 56, Taiyuan, Shanxi, 030001, China
| | - Yanhuan Jia
- School of Mental Health, Shanxi Medical University, South Shifang Street 55, Taiyuan, 030001, China
| | - Jiping Gao
- Laboratory Animal Center, Shanxi Key Laboratory of Experimental Animal Science and Human Disease Animal Model, Shanxi Medical University, Road Xinjian 56, Taiyuan, Shanxi, 030001, China
| | - Xiaotang Wang
- Laboratory Animal Center, Shanxi Key Laboratory of Experimental Animal Science and Human Disease Animal Model, Shanxi Medical University, Road Xinjian 56, Taiyuan, Shanxi, 030001, China
| | - Litao Qin
- Laboratory Animal Center, Shanxi Key Laboratory of Experimental Animal Science and Human Disease Animal Model, Shanxi Medical University, Road Xinjian 56, Taiyuan, Shanxi, 030001, China
| | - Rui Xue
- Laboratory Animal Center, Shanxi Key Laboratory of Experimental Animal Science and Human Disease Animal Model, Shanxi Medical University, Road Xinjian 56, Taiyuan, Shanxi, 030001, China
| | - Guohua Song
- Laboratory Animal Center, Shanxi Key Laboratory of Experimental Animal Science and Human Disease Animal Model, Shanxi Medical University, Road Xinjian 56, Taiyuan, Shanxi, 030001, China; School of Mental Health, Shanxi Medical University, South Shifang Street 55, Taiyuan, 030001, China.
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Wang D, Leng X, Tian Y, Liu J, Zou J, Xie S. Toxic Effects of Koumine on the Early-Life Development Stage of Zebrafish. TOXICS 2023; 11:853. [PMID: 37888703 PMCID: PMC10611223 DOI: 10.3390/toxics11100853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 09/16/2023] [Accepted: 09/27/2023] [Indexed: 10/28/2023]
Abstract
Koumine is one of the most abundant alkaloids found in Gelsemium elegans, and it has a wide range of pharmacological effects including antitumor, anti-inflammatory, analgesic treatment effects, and antianxiety. However, its high toxicity and unclear mechanism of action have greatly limited the medicinal development and use of koumine. We investigated the toxic effects of koumine on the developmental toxicity and behavioral neurotoxicity of zebrafish embryos and larvae. Embryos at 6 h postfertilization (hpf) were exposed to 12.5, 25, 50, 75, and 100 mg/L of koumine until 120 hpf. Koumine affected the hatching and heartbeats of the embryos. The morphological analysis also revealed many abnormalities, such as shortened bodies, yolk sac edemas, tail malformations, and pericardial edemas. To identify the neurotoxicity of koumine, the behavior of the larvae was measured. Koumine at 50 and 100 mg/L affect the escape response. The embryos exhibited uncoordinated muscle contractions along the body axis in response to touch at 36 hpf. More importantly, we found that the neurotoxicity of koumine is mainly caused by influencing the ACh content and the activity of AChE without impairing motor neuron development. A comprehensive analysis shows that a high concentration of koumine has obvious toxic effects on zebrafish, and the safe concentration of koumine for zebrafish should be less than 25 mg/L. These results will be valuable for better understanding the toxicity of koumine and provide new insights into the application of koumine.
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Affiliation(s)
- Dongjie Wang
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China;
| | - Xinyi Leng
- College of Life Sciences, Wuhan University, Wuhan 430000, China; (X.L.); (J.L.)
| | - Yao Tian
- Global Health Institute, School of Life Science, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland;
| | - Jiangdong Liu
- College of Life Sciences, Wuhan University, Wuhan 430000, China; (X.L.); (J.L.)
| | - Jixing Zou
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China;
| | - Shaolin Xie
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China;
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Kennedy C, van Onselen R, Downing TG. β-N-methylamino-l-alanine is a non-competitive inhibitor of vesicular monoamine transporter 2. Toxicon 2023; 222:106978. [PMID: 36410456 DOI: 10.1016/j.toxicon.2022.106978] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 11/04/2022] [Accepted: 11/18/2022] [Indexed: 11/20/2022]
Abstract
The neurotoxic, non-proteinogenic amino acid β-N-methylamino-l-alanine (BMAA) has been implicated in the development of neurodegenerative diseases; however, the mechanism(s) and mode(s) of toxicity remain unclear. Similarities in the neuropathology and behavioural deficits of neonatal rats exposed to either BMAA or reserpine, a known vesicular monoamine transporter 2 (VMAT2) inhibitor, suggest a similar mode of action. The aims of this study were therefore to determine if BMAA could prevent the uptake of serotonin into dense granules via inhibition of VMAT2, and, if so, the type of inhibition caused by BMAA. Exposing platelet dense granules to BMAA resulted in a concentration-dependent reduction in serotonin uptake. The inhibition of VMAT2 was non-competitive. The findings from this study support previous reports that BMAA-associated neuropathologies in a neonatal rat model may be due to VMAT2 inhibition during critical periods of neurogenesis.
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Affiliation(s)
- Chanté Kennedy
- Department of Biochemistry and Microbiology, Nelson Mandela University, P.O. Box 77000, Port Elizabeth, 6021, South Africa.
| | - Rianita van Onselen
- Department of Biochemistry and Microbiology, Nelson Mandela University, P.O. Box 77000, Port Elizabeth, 6021, South Africa; Biomedical Research and Innovation Platform, South African Medical Research Council, Cape Town, South Africa.
| | - Tim G Downing
- Department of Biochemistry and Microbiology, Nelson Mandela University, P.O. Box 77000, Port Elizabeth, 6021, South Africa.
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Li Y, Yin Q, Wang B, Shen T, Luo W, Liu T. Preclinical reserpine models recapitulating motor and non-motor features of Parkinson’s disease: Roles of epigenetic upregulation of alpha-synuclein and autophagy impairment. Front Pharmacol 2022; 13:944376. [PMID: 36313295 PMCID: PMC9597253 DOI: 10.3389/fphar.2022.944376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 09/30/2022] [Indexed: 11/13/2022] Open
Abstract
Reserpine is an effective drug for the clinical treatment of hypertension. It also induces Parkinson’s disease (PD)-like symptoms in humans and animals possible through the inhibition of monoamine vesicular transporters, thus decreasing the levels of monoamine neurotransmitters in the brain. However, the precise mechanisms remain unclear. Herein, we aimed to develop a preclinical reserpine model recapitulating the non-motor and motor symptoms of PD and investigate the underlying potential cellular mechanisms. Incubation of reserpine induced apoptosis, led to the accumulation of intracellular reactive oxygen species (ROS), lowered DNA methylation of alpha-synuclein gene, resulted in alpha-synuclein protein deposition, and elevated the ratio of LC3-II/LC3-Ⅰ and p62 in cultured SH-SY5Y cells. Feeding reserpine dose-dependently shortened the lifespan and caused impairment of motor functions in male and female Drosophila. Moreover, long-term oral administration of reserpine led to multiple motor and non-motor symptoms, including constipation, pain hypersensitivity, olfactory impairment, and depression-like behaviors in mice. The mechanistic studies showed that chronic reserpine exposure caused hypomethylation of the alpha-synuclein gene and up-regulated its expression and elevated the ratio of LC3-II/LC3-Ⅰ and expression of p62 in the substantia nigra of mice. Thus, we established preclinical animal models using reserpine to recapitulate the motor and non-motor symptoms of PD. Chronic reserpine exposure epigenetically elevated the levels of alpha-synuclein expression possible by lowering the DNA methylation status and inducing autophagic impairment in vitro and in vivo.
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Affiliation(s)
- Yang Li
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou, China
- Department of Neurology, Huzhou Central Hospital, Affiliated Central Hospital Huzhou University, Huzhou, China
| | - Qiao Yin
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Bing Wang
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Tingting Shen
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Weifeng Luo
- Department of Neurology and Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou, China
- *Correspondence: Tong Liu, ; Weifeng Luo,
| | - Tong Liu
- Institute of Pain Medicine and Special Environmental Medicine, Nantong University, Nantong, China
- *Correspondence: Tong Liu, ; Weifeng Luo,
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Cunha DMG, Becegato M, Meurer YSR, Lima AC, Gonçalves N, Bioni VS, Engi SA, Bianchi PC, Cruz FC, Santos JR, Silva RH. Neuroinflammation in early, late and recovery stages in a progressive parkinsonism model in rats. Front Neurosci 2022; 16:923957. [PMID: 36090265 PMCID: PMC9459164 DOI: 10.3389/fnins.2022.923957] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 08/04/2022] [Indexed: 11/13/2022] Open
Abstract
Parkinson’s disease (PD) is characterized by motor and non-motor signs, which are accompanied by progressive degeneration of dopaminergic neurons in the substantia nigra. Although the exact causes are unknown, evidence links this neuronal loss with neuroinflammation and oxidative stress. Repeated treatment with a low dose of reserpine—inhibitor of VMAT2—has been proposed as a progressive pharmacological model of PD. The aim of this study was to investigate whether this model replicates the neuroinflammation characteristic of this disease. Six-month-old Wistar rats received repeated subcutaneous injections of reserpine (0.1 mg/kg) or vehicle on alternate days. Animals were euthanized after 5, 10, or 15 injections, or 20 days after the 15th injection. Catalepsy tests (motor assessment) were conducted across treatment. Brains were collected at the end of each treatment period for immunohistochemical and RT-PCR analyzes. Reserpine induced a significant progressive increase in catalepsy duration. We also found decreased immunostaining for tyrosine hydroxylase (TH) in the substantia nigra pars compacta (SNpc) and increased GFAP + cells in the SNpc and dorsal striatum after 10 and 15 reserpine injections. Phenotyping microglial M1 and M2 markers showed increased number of CD11b + cells and percentage of CD11b + /iNOS + cells in reserpine-treated animals after 15 injections, which is compatible with tissue damage and production of cytotoxic factors. In addition, increased CD11b + /ArgI + cells were found 20 days after the last reserpine injection, together with an increment in IL-10 gene expression in the dorsal striatum, which is indicative of tissue repair or regeneration. Reserpine also induced increases in striatal interleukin TNF-alpha mRNA levels in early stages. In view of these results, we conclude that reserpine-induced progressive parkinsonism model leads to neuroinflammation in regions involved in the pathophysiology of PD, which is reversed 20 days after the last injection. These findings reveal that withdrawal period, together with the shift of microglial phenotypes from the pro-inflammatory to the anti-inflammatory stage, may be important for the study of the mechanisms involved in reversing this condition, with potential clinical applicability.
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Affiliation(s)
- Debora M. G. Cunha
- Behavioral Neuroscience Laboratory, Department of Pharmacology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Marcela Becegato
- Behavioral Neuroscience Laboratory, Department of Pharmacology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Ywlliane S. R. Meurer
- Behavioral Neuroscience Laboratory, Department of Pharmacology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Alvaro C. Lima
- Behavioral Neuroscience Laboratory, Department of Pharmacology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Narriman Gonçalves
- Behavioral Neuroscience Laboratory, Department of Pharmacology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Vinícius S. Bioni
- Behavioral Neuroscience Laboratory, Department of Pharmacology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Sheila A. Engi
- Behavioral Neuroscience Laboratory, Department of Pharmacology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Paula C. Bianchi
- Behavioral Neuroscience Laboratory, Department of Pharmacology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Fabio C. Cruz
- Behavioral Neuroscience Laboratory, Department of Pharmacology, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Jose R. Santos
- Behavioral and Evolutionary Neurobiology Laboratory, Department of Bioscience, Universidade Federal do Sergipe, Itabaiana, Brazil
| | - Regina H. Silva
- Behavioral Neuroscience Laboratory, Department of Pharmacology, Universidade Federal de São Paulo, São Paulo, Brazil
- *Correspondence: Regina H. Silva,
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