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Basu S, Song M, Adams L, Jeong I, Je G, Guhathakurta S, Jiang J, Boparai N, Dai W, Cardozo-Pelaez F, Tatulian SA, Han KY, Elliott J, Baum J, McLean PJ, Dickson DW, Kim YS. Transcriptional mutagenesis of α-synuclein caused by DNA oxidation in Parkinson's disease pathogenesis. Acta Neuropathol 2023; 146:685-705. [PMID: 37740734 PMCID: PMC10564827 DOI: 10.1007/s00401-023-02632-7] [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: 01/10/2023] [Revised: 09/09/2023] [Accepted: 09/10/2023] [Indexed: 09/25/2023]
Abstract
Oxidative stress plays an essential role in the development of Parkinson's disease (PD). 8-oxo-7,8-dihydroguanine (8-oxodG, oxidized guanine) is the most abundant oxidative stress-mediated DNA lesion. However, its contributing role in underlying PD pathogenesis remains unknown. In this study, we hypothesized that 8-oxodG can generate novel α-synuclein (α-SYN) mutants with altered pathologic aggregation through a phenomenon called transcriptional mutagenesis (TM). We observed a significantly higher accumulation of 8-oxodG in the midbrain genomic DNA from PD patients compared to age-matched controls, both globally and region specifically to α-SYN. In-silico analysis predicted that forty-three amino acid positions can contribute to TM-derived α-SYN mutation. Here, we report a significantly higher load of TM-derived α-SYN mutants from the midbrain of PD patients compared to controls using a sensitive PCR-based technique. We found a novel Serine42Tyrosine (S42Y) α-SYN as the most frequently detected TM mutant, which incidentally had the highest predicted aggregation score amongst all TM variants. Immunohistochemistry of midbrain sections from PD patients using a newly characterized antibody for S42Y identified S42Y-laden Lewy bodies (LB). We further demonstrated that the S42Y TM variant significantly accelerates WT α-SYN aggregation by cell and recombinant protein-based assays. Cryo-electron tomography revealed that S42Y exhibits considerable conformational heterogeneity compared to WT fibrils. Moreover, S42Y exhibited higher neurotoxicity compared to WT α-SYN as shown in mouse primary cortical cultures and AAV-mediated overexpression in the substantia nigra of C57BL/6 J mice. To our knowledge, this is the first report describing the possible contribution of TM-generated mutations of α-SYN to LB formation and PD pathogenesis.
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Affiliation(s)
- Sambuddha Basu
- Burnett School of Biomedical Sciences, UCF College of Medicine, University of Central Florida, Orlando, FL, 32827, USA
| | - Minkyung Song
- Department of Neurology, Robert Wood Johnson Medical School, Institute for Neurological Therapeutics at Rutgers, Rutgers Biomedical and Health Sciences, 683 Hoes Lane West, Piscataway, NJ, 08854, USA
| | - Levi Adams
- Department of Neurology, Robert Wood Johnson Medical School, Institute for Neurological Therapeutics at Rutgers, Rutgers Biomedical and Health Sciences, 683 Hoes Lane West, Piscataway, NJ, 08854, USA
| | - Inhye Jeong
- Department of Neurology, Robert Wood Johnson Medical School, Institute for Neurological Therapeutics at Rutgers, Rutgers Biomedical and Health Sciences, 683 Hoes Lane West, Piscataway, NJ, 08854, USA
| | - Goun Je
- Burnett School of Biomedical Sciences, UCF College of Medicine, University of Central Florida, Orlando, FL, 32827, USA
| | - Subhrangshu Guhathakurta
- Burnett School of Biomedical Sciences, UCF College of Medicine, University of Central Florida, Orlando, FL, 32827, USA
| | - Jennifer Jiang
- Department of Cell Biology and Neuroscience, Institute for Quantitative Biomedicine, Rutgers University, Piscataway, NJ, 08854, USA
| | - Nikpreet Boparai
- Department of Cell Biology and Neuroscience, Institute for Quantitative Biomedicine, Rutgers University, Piscataway, NJ, 08854, USA
| | - Wei Dai
- Department of Cell Biology and Neuroscience, Institute for Quantitative Biomedicine, Rutgers University, Piscataway, NJ, 08854, USA
| | - Fernando Cardozo-Pelaez
- Center for Environmental Health Sciences, University of Montana, Missoula, MT, 59812, USA
- Center for Structural and Functional Neurosciences, University of Montana, Missoula, MT, 59812, USA
| | - Suren A Tatulian
- Department of Physics, University of Central Florida, Orlando, FL, 32816, USA
| | - Kyu Young Han
- CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, FL, USA
| | - Jordan Elliott
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, 08854, USA
| | - Jean Baum
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, 08854, USA
| | - Pamela J McLean
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Rd, Jacksonville, FL, 32224, USA
| | - Dennis W Dickson
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Rd, Jacksonville, FL, 32224, USA
| | - Yoon-Seong Kim
- Department of Neurology, Robert Wood Johnson Medical School, Institute for Neurological Therapeutics at Rutgers, Rutgers Biomedical and Health Sciences, 683 Hoes Lane West, Piscataway, NJ, 08854, USA.
- Burnett School of Biomedical Sciences, UCF College of Medicine, University of Central Florida, Orlando, FL, 32827, USA.
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Je G, Sun Y, Keyhanian K, Yaghi S, Henninger N. Dorsal vagal nucleus involvement relates to QTc-prolongation after acute medullary infarction. Acta Neurol Scand 2021; 144:283-287. [PMID: 33939183 DOI: 10.1111/ane.13445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 04/04/2021] [Accepted: 04/16/2021] [Indexed: 01/11/2023]
Abstract
BACKGROUND Infarction of the medulla has been associated with prolongation of the QTc, severe arrhythmia, and sudden cardiac death, yet the precise anatomical substrate remains uncertain. AIMS We sought to determine the possible anatomical structures relating to QTc-prolongation in patients with acute medullary infarction. METHODS We included 12 subjects with acute ischemic medullary infarction on brain MRI, who presented within 4.5 h from the last known well time, with a 90-day follow-up. For an unbiased lesion analysis, medullary infarcts were manually outlined on diffusion weighted MRI and co-registered with an anatomical atlas. RESULTS Nine out of 12 had QTc-prolongation. Qualitative and semi-quantitative comparisons were made between infarct location and QTc-prolongation. Among patients with QTc-prolongation, the greatest degree of congruence of the infarct location was over the dorsal vagal nucleus (DVN, 8 out of 9). There was a significant correlation between the number of sections showing infarction of the DVN and presence of QTc-prolongation (r = .582, p = .047). Among patients without QTc-prolongation, the maximum lesion overlap included the medial aspect of the gigantocelluar reticular nucleus of the reticular formation. CONCLUSION We found that the DVN is a key anatomical substrate related to QTc-prolongation. Further studies with more patients and high-resolution, volumetric MRI are needed to confirm our findings.
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Affiliation(s)
- Goun Je
- Department of Neurology University of Massachusetts Medical School Worcester MA USA
| | - Yuyao Sun
- Department of Neurology University of Massachusetts Medical School Worcester MA USA
| | - Kiandokht Keyhanian
- Department of Neurology University of Massachusetts Medical School Worcester MA USA
| | - Shadi Yaghi
- NYU Grossman School of Medicine New York NY USA
- Department of Neurology NYU Langone Health New York NY USA
| | - Nils Henninger
- Department of Neurology University of Massachusetts Medical School Worcester MA USA
- Department of Psychiatry University of Massachusetts Medical School Worcester MA USA
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Je G, Arora S, Raithatha S, Barrette R, Valizadeh N, Shah U, Desai D, Deb A, Desai S. Epidemiology of Parkinson's Disease in Rural Gujarat, India. Neuroepidemiology 2021; 55:188-195. [PMID: 33951636 DOI: 10.1159/000515030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 02/01/2021] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION In India, there have been only few published studies of Parkinson's disease (PD) showing a wide range of prevalence. We conducted this study to determine the prevalence of PD in the rural population of Gujarat, in the western region of India. METHODS This cross-sectional descriptive study was conducted in the villages of Anand, a district of Gujarat, India, between September 2019 and February 2020. This study used a multistep approach including a screening questionnaire and video recording followed by clinical examination by a neurologist, laboratory evaluation, and brain imaging to evaluate patients with PD. RESULTS A total population of 18,896 was screened. The overall crude prevalence of PD was 42.3 per 100,000, and the prevalence over the age of 60 was 308.9 per 100,000 which showed the trend of increasing disease prevalence with age. Their mean duration of illness was 39.3 ± 27.3 months, and more than half of patients with PD had multiple associated nonmotor symptoms and nearly one-third had comorbid anxiety or depression. Environmental factors are important in the pathogenesis of PD, but there was no clear association between patients with PD and certain variables including consumption of well water, exposure to pesticides or other toxins, smoking cigarettes, and drinking alcohol or coffee in our study. CONCLUSIONS The present study showed the current epidemiological data of PD from Gujarat, in western India. Further studies across different regions in India need to be encouraged for better understanding of PD prevalence in the Indian population.
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Affiliation(s)
- Goun Je
- Department of Neurology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Swati Arora
- Department of Extension Programmes, Charutar Arorgya Mandal, Shree Krishna Hospital, Bhaikaka University, Anand, India
| | - Shyamsundar Raithatha
- Department of Extension Programmes, Charutar Arorgya Mandal, Shree Krishna Hospital, Bhaikaka University, Anand, India.,Department of Community Medicine, Charutar Arorgya Mandal, Shree Krishna Hospital and Pramukhswami Medical College, Bhaikaka University, Anand, India
| | - Ryan Barrette
- Department of Neurology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Navid Valizadeh
- Department of Neurology, HonorHealth John C. Lincoln Medical Center, Phoenix, Arizona, USA
| | - Utkarsh Shah
- Department of Community Medicine, Charutar Arorgya Mandal, Shree Krishna Hospital and Pramukhswami Medical College, Bhaikaka University, Anand, India
| | - Devangi Desai
- Department of Medicine, Charutar Arorgya Mandal, Shree Krishna Hospital and Pramukhswami Medical College, Bhaikaka University, Anand, India
| | - Anindita Deb
- Department of Neurology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Soaham Desai
- Department of Neurology, Charutar Arorgya Mandal, Shree Krishna Hospital and Pramukhswami Medical College, Bhaikaka University, Anand, India
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Je G, Sun Y, Keyhanian K, Henninger N. Abstract P130: QTc Prolongation in Acute Medullary Infarction Maps to the Dorsal Vagal Nucleus. Stroke 2021. [DOI: 10.1161/str.52.suppl_1.p130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective:
To determine the spatial relationship between acute medullary infarction and QTc prolongation.
Background:
Ischemic stroke has been associated with QTc-prolongation which increases the risk of cardiac arrhythmia and sudden cardiac death. In particular, pathological arrhythmia and unexpected sudden cardiac death has been described after acute medullary infarction (AMI). Nevertheless, it is not well understood why only as subset of patients with AMI develop significant cardiac arrhythmia. To gain insight into this issue, we sought to determine the possible anatomical structures relating to QTc-prolongation in patients.
Methods:
We retrospectively reviewed 1072 consecutive adult patients admitted for an acute ischemic stroke or a transient ischemic attack, who presented within 4.5 hours from the last known well time and had an admission ECG available. 724 patients had brain MRIs and among these, 13 (1.8 %) patients had an AMI and were included. For an unbiased lesion analyses, medullary infarcts were manually outlined on diffusion weighted MRI and manually co-registered with an anatomical atlas. Infarct lesions were then superimposed on each other as stratified by normal versus prolonged (men > 430 ms, women > 450 ms) QTc to determine the area of greatest degree of congruence.
Results:
76.9 % of patients (10 out of 13, 9 men and 1 woman) had a prolonged QTc (476.9 ± 43.3 ms for men, 515 ms for women). There was no significant difference in electrolyte levels and preexisting comorbidities between subjects with normal and prolonged QTc. Among patients with QTc prolongation, the greatest degree of congruence of the infarct location was the dorsal vagal nucleus (DVN, 7 out of 10 patients).
Conclusions:
Our unbiased lesion segmentation approach identified the DVN a key anatomical substrate related to QTc-prolongation. Biological plausibility of our data and the presence of a causal link between the DVN and cardiac arrhythmia stems from the prior animal experimental data showing that selectively silencing the DVN via a pharmacogenetic approach caused QTc-prolongation in the rat. Further studies with more patients and high-resolution, volumetric MRI are needed to confirm our findings.
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Affiliation(s)
- Goun Je
- Neurology, Univ of Massachusetts Med Sch, Worcester, MA
| | - Yuyao Sun
- Neurology, Univ of Massachusetts Med Sch, Worcester, MA
| | | | - Nils Henninger
- Neurology, Psychiatry, Univ of Massachusetts Med Sch, Worcester, MA
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Abstract
Background: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease of upper and lower motor neurons with high burden on society. Despite tremendous efforts over the last several decades, there is still no definite cure for ALS. Up to now, only two disease-modifying agents, riluzole and edaravone, are approved by U.S. Food and Drug Administration (FDA) for ALS treatment, which only modestly improves survival and disease progression. Major challenging issues to find an effective therapy are heterogeneity in the pathogenesis and genetic variability of ALS. As such, stem cell therapy has been recently a focus of both preclinical and clinical investigations of ALS. This is because stem cells have multifaceted features that can potentially target multiple pathogenic mechanisms in ALS even though its underlying mechanisms are not completely elucidated. Methods & Results: Here, we will have an overview of stem cell therapy in ALS, including their therapeutic mechanisms, the results of recent clinical trials as well as ongoing clinical trials. In addition, we will further discuss complications and limitations of stem cell therapy in ALS. Conclusion: The determination of whether stem cells offer a viable treatment strategy for ALS rests on well-designed and appropriately powered future clinical trials. Randomized, double-blinded, and sham-controlled studies would be valuable.
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Affiliation(s)
- Goun Je
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA USA
| | - Kiandokht Keyhanian
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA USA
| | - Mehdi Ghasemi
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA USA
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Guhathakurta S, Kim J, Adams L, Basu S, Song MK, Adler E, Je G, Fiadeiro MB, Kim Y. Targeted attenuation of elevated histone marks at SNCA alleviates α-synuclein in Parkinson's disease. EMBO Mol Med 2021; 13:e12188. [PMID: 33428332 PMCID: PMC7863397 DOI: 10.15252/emmm.202012188] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 11/30/2020] [Accepted: 12/02/2020] [Indexed: 01/19/2023] Open
Abstract
Epigenetic deregulation of α-synuclein plays a key role in Parkinson's disease (PD). Analysis of the SNCA promoter using the ENCODE database revealed the presence of important histone post-translational modifications (PTMs) including transcription-promoting marks, H3K4me3 and H3K27ac, and repressive mark, H3K27me3. We investigated these histone marks in post-mortem brains of controls and PD patients and observed that only H3K4me3 was significantly elevated at the SNCA promoter of the substantia nigra (SN) of PD patients both in punch biopsy and in NeuN-positive neuronal nuclei samples. To understand the importance of H3K4me3 in regulation of α-synuclein, we developed CRISPR/dCas9-based locus-specific H3K4me3 demethylating system where the catalytic domain of JARID1A was recruited to the SNCA promoter. This CRISPR/dCas9 SunTag-JARID1A significantly reduced H3K4me3 at SNCA promoter and concomitantly decreased α-synuclein both in the neuronal cell line SH-SY5Y and idiopathic PD-iPSC derived dopaminergic neurons. In sum, this study indicates that α-synuclein expression in PD is controlled by SNCA's histone PTMs and modulation of the histone landscape of SNCA can reduce α-synuclein expression.
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Affiliation(s)
- Subhrangshu Guhathakurta
- Burnett School of Biomedical SciencesUCF College of MedicineUniversity of Central FloridaOrlandoFLUSA
| | - Jinil Kim
- Burnett School of Biomedical SciencesUCF College of MedicineUniversity of Central FloridaOrlandoFLUSA
- NexmosYongin‐SiSouth Korea
| | - Levi Adams
- Burnett School of Biomedical SciencesUCF College of MedicineUniversity of Central FloridaOrlandoFLUSA
- Robert Wood Johnson Medical School Institute for Neurological TherapeuticsRutgers Biomedical and Health SciencesPiscatawayNJUSA
| | - Sambuddha Basu
- Burnett School of Biomedical SciencesUCF College of MedicineUniversity of Central FloridaOrlandoFLUSA
| | - Min Kyung Song
- Burnett School of Biomedical SciencesUCF College of MedicineUniversity of Central FloridaOrlandoFLUSA
- Robert Wood Johnson Medical School Institute for Neurological TherapeuticsRutgers Biomedical and Health SciencesPiscatawayNJUSA
| | - Evan Adler
- Burnett School of Biomedical SciencesUCF College of MedicineUniversity of Central FloridaOrlandoFLUSA
| | - Goun Je
- Burnett School of Biomedical SciencesUCF College of MedicineUniversity of Central FloridaOrlandoFLUSA
| | - Mariana Bernardo Fiadeiro
- Burnett School of Biomedical SciencesUCF College of MedicineUniversity of Central FloridaOrlandoFLUSA
| | - Yoon‐Seong Kim
- Burnett School of Biomedical SciencesUCF College of MedicineUniversity of Central FloridaOrlandoFLUSA
- Robert Wood Johnson Medical School Institute for Neurological TherapeuticsRutgers Biomedical and Health SciencesPiscatawayNJUSA
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Abstract
Myasthenia gravis (MG) is an autoimmune disorder of neuromuscular junction that has higher incidence in younger women than men, which could be related to differences in sex hormones physiology and immune system functioning between males and females. MG can first present during pregnancy and variably affect pregnancy, labor, and postpartum period. In this paper, we had an updated overview on our understanding about MG presentation and its effect on pregnancy and vice versa, therapeutic options for MG pregnant women, management of pregnancy or labor complications in MG patients, and finally fetal and neonatal considerations in MG pregnant women. A multidisciplinary approach, involving obstetricians/gynecologists, neurologists, and anes-thesiologists, plays a pivotal role in improving the clinical outcomes in both MG mothers and their infants during pregnancy, delivery and postpartum.
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Affiliation(s)
- Goun Je
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01655, United States
| | - Mehdi Ghasemi
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01655, United States
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Cristóvão AC, Campos FL, Je G, Esteves M, Guhathakurta S, Yang L, Beal MF, Fonseca BM, Salgado AJ, Queiroz J, Sousa N, Bernardino L, Alves G, Yoon KS, Kim YS. Characterization of a Parkinson's disease rat model using an upgraded paraquat exposure paradigm. Eur J Neurosci 2020; 52:3242-3255. [PMID: 31958881 DOI: 10.1111/ejn.14683] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 01/09/2020] [Accepted: 01/13/2020] [Indexed: 12/12/2022]
Abstract
Animal models of human diseases are crucial experimental tools to investigate the mechanisms involved in disease pathogenesis and to develop new therapies. In spite of the numerous animal models currently available that reproduce several neuropathological features of Parkinson disease (PD), it is challenging to have one that consistently recapitulates human PD conditions in both motor behaviors and biochemical pathological outcomes. Given that, we have implemented a new paradigm to expose rats to a chronic low dose of paraquat (PQ), using osmotic minipumps and characterized the developed pathologic features over time. The PQ exposure paradigm used lead to a rodent model of PD depicting progressive nigrostriatal dopaminergic neurodegeneration, characterized by a 41% significant loss of dopaminergic neuron in the substantia nigra pars compacta (SNpc), a significant decrease of 18% and 40% of dopamine levels in striatum at week 5 and 8, respectively, and a significant 1.5-fold decrease in motor performance. We observed a significant increase of microglia activation state, sustained levels of α-synucleinopathy and increased oxidative stress markers in the SNpc. In summary, this is an explorative study that allowed to characterize an improved PQ-based rat model that recapitulates cardinal features of PD and may represent an attractive tool to investigate several mechanisms underlying the various aspects of PD pathogenesis as well as for the validation of the efficacy of new therapeutic approaches that targets different mechanisms involved in PD neurodegeneration.
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Affiliation(s)
- Ana Clara Cristóvão
- CICS-UBI Health Sciences Research Center, University of Beira Interior, Covilhã, Portugal.,NeuroSoV, UBIMedical, Universidade da Beira Interior, Covilhã, Portugal
| | - Filipa L Campos
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Goun Je
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Marta Esteves
- CICS-UBI Health Sciences Research Center, University of Beira Interior, Covilhã, Portugal
| | - Subhrangshu Guhathakurta
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Lichuan Yang
- Neuroscience Department, Weill Medical College of Cornell University, New York, NY, USA
| | - M Flint Beal
- Neuroscience Department, Weill Medical College of Cornell University, New York, NY, USA
| | - Beatriz M Fonseca
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Antonio J Salgado
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - João Queiroz
- CICS-UBI Health Sciences Research Center, University of Beira Interior, Covilhã, Portugal
| | - Nuno Sousa
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Liliana Bernardino
- CICS-UBI Health Sciences Research Center, University of Beira Interior, Covilhã, Portugal
| | - Gilberto Alves
- CICS-UBI Health Sciences Research Center, University of Beira Interior, Covilhã, Portugal.,CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Kyung-Sik Yoon
- Department of Biochemistry and Molecular Biology, Kyung-Hee University Medical College, Seoul, South Korea
| | - Yoon-Seong Kim
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA.,Department of Biochemistry and Molecular Biology, Kyung-Hee University Medical College, Seoul, South Korea
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Je G, Guhathakurta S, Yun SP, Ko HS, Kim YS. A novel extended form of alpha-synuclein 3'UTR in the human brain. Mol Brain 2018; 11:29. [PMID: 29801501 PMCID: PMC5970512 DOI: 10.1186/s13041-018-0371-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [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: 03/05/2018] [Accepted: 05/15/2018] [Indexed: 11/10/2022] Open
Abstract
Alpha-synuclein (α-SYN) is one of the key contributors in Parkinson's disease (PD) pathogenesis. Despite the fact that increased α-SYN levels are considered one of the key contributors in developing PD, the molecular mechanisms underlying the regulation of α-SYN still needs to be elucidated. Since the 3' untranslated regions (3'UTRs) of messenger RNAs (mRNAs) have important roles in translation, localization, and stability of mRNAs through RNA binding proteins (RBPs) and microRNAs (miRNAs), it is important to identify the exact length of 3'UTRs of transcripts in order to understand the precise regulation of gene expression. Currently annotated human α-SYN mRNA has a relatively long 3'UTR (2529 nucleotides [nt]) with several isoforms. RNA-sequencing and epigenomics data have suggested, however, the possible existence of even longer transcripts which extend beyond the annotated α-SYN 3'UTR sequence. Here, we have discovered the novel extended form of α-SYN 3'UTR (3775 nt) in the substantia nigra of human postmortem brain samples, induced pluripotent stem cell (iPSC)-derived dopaminergic neurons, and other human neuronal cell lines. Interestingly, the longer variant reduced α-SYN translation. The extended α-SYN 3'UTR was significantly lower in iPSC-derived dopaminergic neurons from sporadic PD patients than controls. On the other hand, α-SYN protein levels were much higher in PD cases, showing the strong negative correlation with the extended 3'UTR. These suggest that dysregulation of the extended α-SYN 3'UTR might contribute to the pathogenesis of PD.
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Affiliation(s)
- Goun Je
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Subhrangshu Guhathakurta
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Seung Pil Yun
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Adrienne Helis Malvin Medical Research Foundation, New Orleans, LA, USA
| | - Han Seok Ko
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Adrienne Helis Malvin Medical Research Foundation, New Orleans, LA, USA.,Diana Helis Henry Medical Research Foundation, New Orleans, LA, USA
| | - Yoon-Seong Kim
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA. .,College of Medicine, Kyung-Hee University, Seoul, South Korea.
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Croop B, Je G, Tang J, Kim YS, Young Han K. Endogenous Alpha-Synuclein Analysis using Single-Molecule Pull-Down Assay. Biophys J 2018. [DOI: 10.1016/j.bpj.2017.11.2161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Je G, Croop B, Basu S, Tang J, Han KY, Kim YS. Endogenous Alpha-Synuclein Protein Analysis from Human Brain Tissues Using Single-Molecule Pull-Down Assay. Anal Chem 2017; 89:13044-13048. [PMID: 29172450 DOI: 10.1021/acs.analchem.7b04335] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Alpha-synuclein (α-SYN) is a central molecule in Parkinson's disease pathogenesis. Despite several studies, the molecular nature of endogenous α-SYN especially in human brain samples is still not well understood due to the lack of reliable methods and the limited amount of biospecimens. Here, we introduce α-SYN single-molecule pull-down (α-SYN SiMPull) assay combined with in vivo protein crosslinking to count individual α-SYN protein and assess its native oligomerization states from biological samples including human postmortem brains. This powerful single-molecule assay can be highly useful in diagnostic applications using various specimens for neurodegenerative diseases including Alzheimer's disease and Parkinson's disease.
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Affiliation(s)
- Goun Je
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida , Orlando, Florida 32827, United States
| | - Benjamin Croop
- CREOL, The College of Optics and Photonics, University of Central Florida , Orlando Florida 32816, United States
| | - Sambuddha Basu
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida , Orlando, Florida 32827, United States
| | - Jialei Tang
- CREOL, The College of Optics and Photonics, University of Central Florida , Orlando Florida 32816, United States
| | - Kyu Young Han
- CREOL, The College of Optics and Photonics, University of Central Florida , Orlando Florida 32816, United States
| | - Yoon-Seong Kim
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida , Orlando, Florida 32827, United States
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Je G, Kim YS. Mitochondrial ROS-mediated post-transcriptional regulation of α-synuclein through miR-7 and miR-153. Neurosci Lett 2017; 661:132-136. [PMID: 28986122 DOI: 10.1016/j.neulet.2017.09.065] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 09/28/2017] [Accepted: 09/30/2017] [Indexed: 12/21/2022]
Abstract
Dysregulation of human alpha-synuclein (α-SYN) is one of the major contributors in the pathogenesis of Parkinson's disease. 1-methyl-4-phenylpyridinium (MPP+) is well known neurotoxin which increases α-SYN expression and causes dopaminergic neuronal death. Increasing evidence suggests microRNAs (miRNAs), especially miRNA-7 and miR-153, have important role in the regulation of α-SYN translation and they can prevent MPP+-mediated neuronal death. Here, we examined whether MPP+-mediated upregulation of α-SYN expression is directly related to miRNA-7 and miR-153. First, we established HEK293/TR cells stably expressing both miR-7 and miR-153. Human α-SYN 3'-UTR containing target sites for both miRNAs was cloned next to a luciferase reporter construct. To control the total levels of reporter mRNA, a tetracycline-inducible system was used. Compared to wild-type HEK293/TR cells, cells overexpressing both miRNAs demonstrated about 75% reduction in luciferase activity. MPP+ treatment, however, significantly increased luciferase activity of human α-SYN 3'-UTR. Either quenching mitochondrial reactive oxygen species (ROS) or translational inhibition significantly reduced MPP+-mediated luciferase activity, suggesting mitochondrial ROS is responsible for MPP+-induced α-SYN translation. Together, our results suggest that MPP+-mediated increased α-SYN levels are contributed by mitochondrial ROS-mediated de novo protein synthesis which is regulated by miRNA-7 and miR-153.
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Affiliation(s)
- Goun Je
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Yoon-Seong Kim
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA; Kyung Hee University, School of Medicine, Seoul, South Korea.
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Rocha SM, Saraiva T, Cristóvão AC, Ferreira R, Santos T, Esteves M, Saraiva C, Je G, Cortes L, Valero J, Alves G, Klibanov A, Kim YS, Bernardino L. Histamine induces microglia activation and dopaminergic neuronal toxicity via H1 receptor activation. J Neuroinflammation 2016; 13:137. [PMID: 27260166 PMCID: PMC4893260 DOI: 10.1186/s12974-016-0600-0] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [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: 02/07/2016] [Accepted: 05/26/2016] [Indexed: 12/13/2022] Open
Abstract
Background Histamine is an amine widely known as a peripheral inflammatory mediator and as a neurotransmitter in the central nervous system. Recently, it has been suggested that histamine acts as an innate modulator of microglial activity. Herein, we aimed to disclose the role of histamine in microglial phagocytic activity and reactive oxygen species (ROS) production and to explore the consequences of histamine-induced neuroinflammation in dopaminergic (DA) neuronal survival. Methods The effect of histamine on phagocytosis was assessed both in vitro by using a murine N9 microglial cell line and primary microglial cell cultures and in vivo. Cells were exposed to IgG-opsonized latex beads or phosphatidylserine (PS) liposomes to evaluate Fcγ or PS receptor-mediated microglial phagocytosis, respectively. ROS production and protein levels of NADPH oxidases and Rac1 were assessed as a measure of oxidative stress. DA neuronal survival was evaluated in vivo by counting the number of tyrosine hydroxylase-positive neurons in the substantia nigra (SN) of mice. Results We found that histamine triggers microglial phagocytosis via histamine receptor 1 (H1R) activation and ROS production via H1R and H4R activation. By using apocynin, a broad NADPH oxidase (Nox) inhibitor, and Nox1 knockout mice, we found that the Nox1 signaling pathway is involved in both phagocytosis and ROS production induced by histamine in vitro. Interestingly, both apocynin and annexin V (used as inhibitor of PS-induced phagocytosis) fully abolished the DA neurotoxicity induced by the injection of histamine in the SN of adult mice in vivo. Blockade of H1R protected against histamine-induced Nox1 expression and death of DA neurons in vivo. Conclusions Overall, our results highlight the relevance of histamine in the modulation of microglial activity that ultimately may interfere with neuronal survival in the context of Parkinson’s disease (PD) and, eventually, other neurodegenerative diseases which are accompanied by microglia-induced neuroinflammation. Importantly, our results also open promising new perspectives for the therapeutic use of H1R antagonists to treat or ameliorate neurodegenerative processes. Electronic supplementary material The online version of this article (doi:10.1186/s12974-016-0600-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sandra M Rocha
- Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal
| | - Tatiana Saraiva
- Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal
| | - Ana C Cristóvão
- Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal
| | - Raquel Ferreira
- Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal
| | - Tiago Santos
- Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal
| | - Marta Esteves
- Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal
| | - Cláudia Saraiva
- Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal
| | - Goun Je
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Luísa Cortes
- Center for Neuroscience and Cell Biology, Coimbra, Portugal
| | - Jorge Valero
- Center for Neuroscience and Cell Biology, Coimbra, Portugal
| | - Gilberto Alves
- Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal
| | - Alexander Klibanov
- Division of Cardiovascular Medicine and Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Yoon-Seong Kim
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Liliana Bernardino
- Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal. .,Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506, Covilhã, Portugal.
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Yoo SD, Park JS, Yun DH, Kim HS, Kim SK, Kim DH, Chon J, Je G, Kim YS, Chung JH, Chung SJ, Yeo JA. Polymorphism of Nitric Oxide Synthase 1 Affects the Clinical Phenotypes of Ischemic Stroke in Korean Population. Ann Rehabil Med 2016; 40:102-10. [PMID: 26949676 PMCID: PMC4775742 DOI: 10.5535/arm.2016.40.1.102] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [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: 06/02/2015] [Accepted: 07/22/2015] [Indexed: 11/10/2022] Open
Abstract
Objective To investigate whether four single nucleotide polymorphisms (SNPs) rs2293054 [Ile734Ile], rs1047735 [His902His], rs2293044 [Val1353Val], rs2682826 (3'UTR) of nitric oxide synthase 1 (NOS1) are associated with the development and clinical phenotypes of ischemic stroke. Methods We enrolled 120 ischemic stroke patients and 314 control subjects. Ischemic stroke patients were divided into subgroups according to the scores of the National Institutes of Health Stroke Survey (NIHSS, <6 and ≥6) and Modified Barthel Index (MBI, <60 and ≥60). SNPStats, SNPAnalyzer, and HelixTree programs were used to calculate odds ratios (ORs), 95% confidence intervals (CIs), and p-values. Multiple logistic regression models were performed to analyze genetic data. Results No SNPs of the NOS1 gene were found to be associated with ischemic stroke. However, in an analysis of clinical phenotypes, we found that rs2293054 was associated with the NIHSS scores of ischemic stroke patients in codominant (p=0.019), dominant (p=0.007), overdominant (p=0.033), and log-additive (p=0.0048) models. Also, rs2682826 revealed a significant association in the recessive model (p=0.034). In allele frequency analysis, we also found that the T alleles of rs2293054 were associated with lower NIHSS scores (p=0.007). Respectively, rs2293054 had a significant association in the MBI scores of ischemic stroke in codominant (p=0.038), dominant (p=0.031), overdominant (p=0.045), and log-additive (p=0.04) models. Conclusion These results suggest that NOS1 may be related to the clinical phenotypes of ischemic stroke in Korean population.
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Affiliation(s)
- Seung Don Yoo
- Department of Physical Medicine and Rehabilitaion, Kyung Hee University Medical Center, Seoul, Korea
| | - Jun Sang Park
- Department of Physical Medicine and Rehabilitaion, Kyung Hee University Medical Center, Seoul, Korea
| | - Dong Hwan Yun
- Department of Physical Medicine and Rehabilitaion, Kyung Hee University Medical Center, Seoul, Korea
| | - Hee-Sang Kim
- Department of Physical Medicine and Rehabilitaion, Kyung Hee University Medical Center, Seoul, Korea
| | - Su Kang Kim
- Kohwang Medical Research Institute, Kyung Hee University School of Medicine, Seoul, Korea
| | - Dong Hwan Kim
- Department of Physical Medicine and Rehabilitaion, Kyung Hee University Medical Center, Seoul, Korea
| | - Jinmann Chon
- Department of Physical Medicine and Rehabilitaion, Kyung Hee University Medical Center, Seoul, Korea
| | - Goun Je
- Department of Physical Medicine and Rehabilitaion, Kyung Hee University Medical Center, Seoul, Korea.; Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, Orlando, FL, USA
| | - Yoon-Seong Kim
- Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, Orlando, FL, USA
| | - Joo-Ho Chung
- Kohwang Medical Research Institute, Kyung Hee University School of Medicine, Seoul, Korea
| | - Seung Joon Chung
- Department of Physical Medicine and Rehabilitaion, Kyung Hee University Medical Center, Seoul, Korea
| | - Jin Ah Yeo
- Department of Physical Medicine and Rehabilitaion, Kyung Hee University Medical Center, Seoul, Korea
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Basu S, Je G, Kim YS. Transcriptional mutagenesis by 8-oxodG in α-synuclein aggregation and the pathogenesis of Parkinson's disease. Exp Mol Med 2015; 47:e179. [PMID: 26315598 PMCID: PMC4558488 DOI: 10.1038/emm.2015.54] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 05/13/2015] [Indexed: 12/11/2022] Open
Abstract
Parkinson's disease (PD) is an age-related progressive neurodegenerative disease associated with selective loss of dopaminergic neurons. The characteristic hallmark of the disease is intracytoplasmic proteinacious inclusion bodies called Lewy bodies, primarily consisting of a presynaptic protein α-synuclein. Oxidative stress-mediated damage to macromolecules have been shown to occur frequently in PD. Oxidative damage to DNA in the form of oxidized guanine (8-oxodG) accumulates in both the mitochondrial and nuclear DNA of dopaminergic neurons of the substantia nigra in PD. 8-oxodG-mediated transcriptional mutagenesis has been shown to have the potential to alter phenotype of cells through production of mutant pool of proteins. This review comprehensively summarizes the role of oxidative stress-mediated damage incurred during neurodegeneration, and highlights the scope of transcriptional mutagenesis event in leading to α-synuclein aggregation as seen in PD.
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Affiliation(s)
- Sambuddha Basu
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Goun Je
- Department of Biochemistry, College of Medicine, Kyung-Hee University, Seoul, Korea
| | - Yoon-Seong Kim
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA.,Department of Biochemistry, College of Medicine, Kyung-Hee University, Seoul, Korea
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Campos FL, Carvalho MM, Cristovão AC, Je G, Baltazar G, Salgado AJ, Kim YS, Sousa N. Rodent models of Parkinson's disease: beyond the motor symptomatology. Front Behav Neurosci 2013; 7:175. [PMID: 24324416 PMCID: PMC3840800 DOI: 10.3389/fnbeh.2013.00175] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [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: 08/13/2013] [Accepted: 11/06/2013] [Indexed: 11/23/2022] Open
Abstract
Parkinson's disease (PD) is classically characterized by motor symptoms; however, non-motor symptoms (NMS) are increasingly recognized as relevant in disease-state, given the associated alterations in mood (depression and anxiety) and cognition. Here, particularly in regards to NMS, we aimed to compare the motor, emotional and cognitive behavior of three animal models of PD that trigger dopaminergic (DAergic) degeneration on both brain hemispheres: (i) the 6-hydroxydopamine (6-OHDA, 8 or 6 μg) lesion model; (ii) the paraquat (PQ) induced model, and (iii) a genetic model based on α-synuclein overexpression (α-syn). 6-OHDA and α-syn vector were injected bilaterally in the substantia nigra pars compacta (SNpc) of adult male Wistar rats; as for PQ delivery, micro-osmotic pumps were implanted in the interscapular region. Motor deficits were observed in all models, with histological analysis of tyrosine hydroxylase positive cells in the SNpc revealing a significant loss of DAergic neurons in all animal models. In addition, the α-syn animal model also presented a reduction in exploratory activity, and the 6-OHDA and PQ animals displayed a significant increase in both depressive- and anxiety-like behavior. Interestingly, cognitive impairment (working memory) was only observed in the 6-OHDA model. Overall, these PD models are suitable for mimicking the motor symptoms associated to PD, with each encompassing other relevant NMS components of the disorder that may prove beneficial for further studies in PD.
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Affiliation(s)
- Filipa L Campos
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho Braga, Portugal ; ICVS/3B's, PT Government Associate Laboratory Braga/Guimarães, Portugal
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Cristóvão AC, Barata J, Je G, Kim YS. PKCδ mediates paraquat-induced Nox1 expression in dopaminergic neurons. Biochem Biophys Res Commun 2013; 437:380-5. [PMID: 23827392 DOI: 10.1016/j.bbrc.2013.06.085] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 06/22/2013] [Indexed: 01/18/2023]
Abstract
Our previous works have shown that the (NADPH) oxidase (Nox) enzyme, in particular Nox1, plays an important role in oxidative stress and subsequent dopaminergic cell death elicited by paraquat (PQ). In non-neuronal and glial cells, protein kinase C δ (PKCδ) shows the ability to regulate the activity of the Nox system. Herein we aimed to investigate if also in dopaminergic neurons exposed to PQ, PKCδ can regulate Nox1 expression. The chemical inhibitor, rottlerin, and short interference RNA (siRNA) were used to inhibit or selectively knockdown PKCδ, respectively. The studies were performed using the immortalized rat mesencephalic dopaminergic cell line (N27 cells) exposed to PQ, after pre-incubation with rottlerin or transfected with PKCδ-siRNA. We observed that inhibition or knockdown of PKCδ significantly reduced PQ induced Nox1 transcript and protein levels, ROS generation and subsequent dopaminergic cell death. The results suggest that PKCδ plays a role in the regulation of Nox1-mediated oxidative stress elicited by PQ and could have a role in the pathogenesis of Parkinson's disease.
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Affiliation(s)
- Ana Clara Cristóvão
- University of Central Florida, Burnett School of Biomedical Sciences, College of Medicine, Orlando, Fl, USA.
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