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Chen XL, Tan QD, Chen KJ, Zheng DN, Deng HW, He S, Mao FK, Hao JL, Le WD, Yang J. CircRNA and Stroke: New Insight of Potential Biomarkers and Therapeutic Targets. Neurochem Res 2024; 49:557-567. [PMID: 38063946 DOI: 10.1007/s11064-023-04077-6] [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: 10/09/2023] [Revised: 11/14/2023] [Accepted: 11/25/2023] [Indexed: 02/23/2024]
Abstract
Stroke, the second-largest cause of death and the leading cause of disability globally, presents significant challenges in terms of prognosis and treatment. Identifying reliable prognosis biomarkers and treatment targets is crucial to address these challenges. Circular RNA (circRNA) has emerged as a promising research biomarkers and therapeutic targets because of its tissue specificity and conservation. However, the potential role of circRNA in stroke prognosis and treatment remains largely unexplored. This review briefly elucidate the mechanism underlying circRNA's involvement in stroke pathophysiology. Additionally, this review summarizes the impact of circRNA on different forms of strokes, including ischemic stroke and hemorrhagic stroke. And, this article discusses the positive effects of circRNA on promoting cerebrovascular repair and regeneration, maintaining the integrity of the blood-brain barrier (BBB), and reducing neuronal injury and immune inflammatory response. In conclusion, the significance of circRNA as a potential prognostic biomarker and a viable therapeutic target was underscored.
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Affiliation(s)
- Xiao-Ling Chen
- School of Clinical Medicine, Southwest Medical University, Luzhou, 646000, China
- Department of Neurology, School of Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610072, China
| | - Quan-Dan Tan
- Department of Neurology, The First Affiliated Hospital of Chengdu Medical College, Chengdu, 610072, China9, China
| | - Ke-Jie Chen
- School of Public Health, Chengdu Medical College, Chengdu, 610072, China
| | - Dan-Ni Zheng
- Brain Health Initiative, The George Institute for Global Health, University of New South Wales, Sydney, 2025, Australia
| | - Hong-Wei Deng
- Department of Neurology, The First Affiliated Hospital of Chengdu Medical College, Chengdu, 610072, China9, China
| | - Song He
- Department of Neurology, The First Affiliated Hospital of Chengdu Medical College, Chengdu, 610072, China9, China
| | - Feng-Kai Mao
- Department of Neurology, The First Affiliated Hospital of Chengdu Medical College, Chengdu, 610072, China9, China
| | - Jun-Li Hao
- School of Biomedical Sciences and Technology, Chengdu Medical College, Chengdu, 610072, China
| | - Wei-Dong Le
- Institute of Neurology, School of Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, 610072, China.
| | - Jie Yang
- School of Biomedical Sciences and Technology, Chengdu Medical College, Chengdu, 610072, China.
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Le WD, Yang C, Yang Q, Xiang Y, Zeng XR, Xiao J. The neuroprotective effects of oxygen therapy in Alzheimer’s disease: a narrative review. Neural Regen Res 2023. [PMID: 35799509 PMCID: PMC9241400 DOI: 10.4103/1673-5374.343897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Alzheimer’s disease (AD) is a degenerative neurological disease that primarily affects the elderly. Drug therapy is the main strategy for AD treatment, but current treatments suffer from poor efficacy and a number of side effects. Non-drug therapy is attracting more attention and may be a better strategy for treatment of AD. Hypoxia is one of the important factors that contribute to the pathogenesis of AD. Multiple cellular processes synergistically promote hypoxia, including aging, hypertension, diabetes, hypoxia/obstructive sleep apnea, obesity, and traumatic brain injury. Increasing evidence has shown that hypoxia may affect multiple pathological aspects of AD, such as amyloid-beta metabolism, tau phosphorylation, autophagy, neuroinflammation, oxidative stress, endoplasmic reticulum stress, and mitochondrial and synaptic dysfunction. Treatments targeting hypoxia may delay or mitigate the progression of AD. Numerous studies have shown that oxygen therapy could improve the risk factors and clinical symptoms of AD. Increasing evidence also suggests that oxygen therapy may improve many pathological aspects of AD including amyloid-beta metabolism, tau phosphorylation, neuroinflammation, neuronal apoptosis, oxidative stress, neurotrophic factors, mitochondrial function, cerebral blood volume, and protein synthesis. In this review, we summarized the effects of oxygen therapy on AD pathogenesis and the mechanisms underlying these alterations. We expect that this review can benefit future clinical applications and therapy strategies on oxygen therapy for AD.
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Wang JT, Xu G, Ren RJ, Wang Y, Tang R, Huang Q, Li JP, Al-Nusaif M, Le WD, Wang G. The impacts of health insurance and resource on the burden of Alzheimer's disease and related dementias in the world population. Alzheimers Dement 2022; 19:967-979. [PMID: 35820032 DOI: 10.1002/alz.12730] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 05/28/2022] [Accepted: 06/01/2022] [Indexed: 11/09/2022]
Abstract
INTRODUCTION The increasing prevalence of Alzheimer's disease and related dementias (ADRD) presents both a burden and an opportunity for intervention. This study aims to estimate the impacts of health insurance and resources on the burden attributed to ADRD. METHOD Data were mainly collected from global databases for ADRD. Analysis of variance, Pearson correlation, random-effects, and fixed-effects model analyses were used in this study. RESULTS Although the current medical expenditures were increasing and out of pocket (OOP) expenditures were declining generally in various countries, the collected global data showed an increased burden of ADRD on patients both physically and economically. Furthermore, health resources were negatively associated with disability-adjusted life years (DALY), death, and years of life lost (YLL), but were otherwise positively associated with years of life lived with disability (YLD). DISCUSSION Effective measures should be considered to cope with the rising burden. Meanwhile, there is an urgent call for constructive and sustainable rational plans and global collaboration. HIGHLIGHTS We explored how health insurance and resources affect Alzheimer's disease and related dementias (ADRD)-related burden. Health insurance and resources were imbalanced among four income level groups. Health insurance and resources may decrease the total ADRD burden primarily from a reduction in death-related burden. Health insurance and resources may increase disability-related burden.
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Affiliation(s)
- Jin-Tao Wang
- Department of Neurology & Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Gang Xu
- School of Public Health, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Ru-Jing Ren
- Department of Neurology & Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Ying Wang
- School of Public Health, Fudan University, Shanghai, People's Republic of China
| | - Ran Tang
- Department of Neurology & Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Qiang Huang
- Department of Neurology & Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Jian-Ping Li
- Department of Neurology & Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Murad Al-Nusaif
- Center for Clinical Research on Neurological Diseases, First Affiliated Hospital, Dalian Medical University, Dalian, People's Republic of China
| | - Wei-Dong Le
- Center for Translational Medicine, Shanghai University of Medicine & Health Sciences, Shanghai, People's Republic of China
| | - Gang Wang
- Department of Neurology & Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
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Abstract
Polysaccharides are macromolecular complexes that have various biological activities. In vivo and in vitro studies have shown that polysaccharides play neuroprotective roles through multiple mechanisms; consequently, they have potential in the prevention and treatment of neurodegenerative diseases. This paper summarizes related research published during 2015-2020 and reviews advances in the understanding of the neuroprotective effects of bioactive polysaccharides. This review focuses on 15 bioactive polysaccharides from plants and fungi that have neuroprotective properties against oxidative stress, apoptosis, neuroinflammation, and excitatory amino acid toxicity mainly through the regulation of nuclear factor kappa-B, phosphatidylinositol-3-kinase/protein kinase B, mitogen-activated protein kinase, nuclear factor-E2-related factor 2/ hemeoxygenase-1, c-jun N-terminal kinase, protein kinase B-mammalian target of rapamycin, and reactive oxygen species-nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain-containing 3 signaling pathways. Natural bioactive polysaccharides have potential in the prevention and treatment of neurodegenerative diseases because of their advantageous characteristics, including multi-targeting, low toxicity, and synergistic effects. However, most of the recent related research has focused on cell and animal models. Future randomized clinical trials involving large sample sizes are needed to validate the therapeutic benefits of these neuroprotective polysaccharides in patients having neurodegenerative diseases.
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Affiliation(s)
- Xiao-Lan Xu
- Department of Neurology, Sichuan Academy of Medical Sciences-Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan Province, China
| | - Song Li
- Liaoning Provincial Center for Clinical Research on Neurological Diseases, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning Province, China
| | - Rong Zhang
- Department of Neurology, Sichuan Academy of Medical Sciences-Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan Province, China
| | - Wei-Dong Le
- Department of Neurology, Sichuan Academy of Medical Sciences-Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan Province; Liaoning Provincial Center for Clinical Research on Neurological Diseases, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning Province, China
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Shang HY, Zhang JJ, Fu ZF, Liu YF, Li S, Chen S, Le WD. Therapeutic effects of hirsutella sinensis on the disease onset and progression of amyotrophic lateral sclerosis in SOD1 G93A transgenic mouse model. CNS Neurosci Ther 2019; 26:90-100. [PMID: 31318169 PMCID: PMC6930832 DOI: 10.1111/cns.13182] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [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: 01/25/2019] [Revised: 05/10/2019] [Accepted: 05/21/2019] [Indexed: 12/12/2022] Open
Abstract
Aims Although the pathophysiology of amyotrophic lateral sclerosis (ALS) is still not completely understood, the deregulated microglia polarization and neuroinflammation have been shown to contribute to the pathogenesis and progression of this disease. In the present study, we aimed to determine whether hirsutella sinensis (HS) could reduce neuroinflammatory and pathological changes in the spinal cord of SOD1G93A model mice of ALS and consequently ameliorate disease onset and progression. Methods SOD1G93A mice were chronically treated with HS by gavage. Their lifespan was recorded, and motor behavior was evaluated by rotarod test. The pathological changes in skeletal muscles and motor neurons in spinal cords were assessed by immunofluorescent staining and hematoxylin‐eosin staining. The microglia activation and neuroinflammation were determined by immunofluorescent staining and RT‐PCR. Results Our data suggested that repeated HS administration prolonged the lifespan and extended disease duration of ALS mice without significant delay on disease onset. HS ameliorated the pathological changes in the motor neurons and gastrocnemius muscles. Moreover, HS promoted the transition of microglia from pro‐inflammatory M1 to anti‐inflammatory M2 phenotype in the spinal cord of ALS mice. Conclusion All these findings indicate that HS may serve as a potential therapeutic candidate for the treatment of ALS.
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Affiliation(s)
- Hai-Yan Shang
- Center for Clinical Research on Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China.,Liaoning Provincial Key Laboratory for Research on the Pathogenic Mechanisms of Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China.,General Hospital of Yangtze River Shipping, Wuhan Brain Hospital, Wuhan, China
| | - Jing-Jing Zhang
- Center for Clinical Research on Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China.,Liaoning Provincial Key Laboratory for Research on the Pathogenic Mechanisms of Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China.,Chifeng Municipal Hospital, Chifeng, China
| | - Zhen-Fa Fu
- Center for Clinical Research on Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China.,Liaoning Provincial Key Laboratory for Research on the Pathogenic Mechanisms of Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China
| | - Yu-Fei Liu
- Center for Clinical Research on Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China.,Liaoning Provincial Key Laboratory for Research on the Pathogenic Mechanisms of Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China
| | - Song Li
- Center for Clinical Research on Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China.,Liaoning Provincial Key Laboratory for Research on the Pathogenic Mechanisms of Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China
| | - Sheng Chen
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Wei-Dong Le
- Center for Clinical Research on Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China.,Liaoning Provincial Key Laboratory for Research on the Pathogenic Mechanisms of Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China
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Zhang JJ, Zhou QM, Chen S, Le WD. Repurposing carbamazepine for the treatment of amyotrophic lateral sclerosis in SOD1-G93A mouse model. CNS Neurosci Ther 2018; 24:1163-1174. [PMID: 29656576 DOI: 10.1111/cns.12855] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 02/27/2018] [Accepted: 03/13/2018] [Indexed: 12/12/2022] Open
Abstract
AIMS To investigate the effect and mechanisms of carbamazepine (CBZ) on the onset and progression of amyotrophic lateral sclerosis (ALS) in SOD1-G93A mouse model. METHODS Starting from 64 days of age, SOD1-G93A mice were orally administered with CBZ at 200 mg/kg once daily until death. The disease onset and life span of SOD1-G93A mice were recorded. Motor neurons (MNs) in anterior horn of spinal cord were quantified by Nissl staining and SMI-32 immunostaining. Hematoxylin and eosin (H&E), nicotinamide adenine dinucleotide hydrogen (NADH), modified Gomori trichrome (MGT), and α-bungarotoxin-ATTO-488 staining were also performed to evaluate muscle and neuromuscular junction (NMJ) damage. Expressions of aggregated SOD1 protein and autophagy-related proteins were further detected by Western blot and immunofluorescent staining. RESULTS Carbamazepine treatment could delay the disease onset and extend life span of SOD1-G93A mice by about 14.5% and 13.9%, respectively. Furthermore, CBZ treatment reduced MNs loss by about 46.6% and ameliorated the altered muscle morphology and NMJ. Much more interestingly, mechanism study revealed that CBZ treatment activated autophagy via AMPK-ULK1 pathway and promoted the clearance of mutant SOD1 aggregation. CONCLUSION Our findings uncovered the therapeutic effects of CBZ against disease pathogenesis in SOD1-G93A mice, indicating a promising clinical utilization of CBZ in ALS therapy.
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Affiliation(s)
- Jing-Jing Zhang
- Liaoning Provincial Center for Clinical Research on Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China.,Liaoning Provincial Key Laboratory for Research on the Pathogenic Mechanisms of Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China.,Chifeng Municipal Hospital, Chifeng, China
| | - Qin-Ming Zhou
- Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Sheng Chen
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Wei-Dong Le
- Liaoning Provincial Center for Clinical Research on Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China.,Liaoning Provincial Key Laboratory for Research on the Pathogenic Mechanisms of Neurological Diseases, the First Affiliated Hospital, Dalian Medical University, Dalian, China.,Collaborative Innovation Center for Brain Science, the First Affiliated Hospital, Dalian Medical University, Dalian, China
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Tuo HZ, Tian ZL, Cui YN, Ma XY, Xu CL, Bi HY, Zhang LY, Zhang YB, Le WD, Ondo W. Restless legs syndrome secondary to pontine infarction: Clinical analysis of five cases. Chronic Dis Transl Med 2017; 3:186-190. [PMID: 29063076 PMCID: PMC5643777 DOI: 10.1016/j.cdtm.2017.08.001] [Citation(s) in RCA: 5] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Indexed: 01/13/2023] Open
Abstract
Objective Pontine infarction is a common type of stroke in the cerebral deep structures, resulting from occlusion of small penetrating arteries, may manifest as hemi-paralysis, hemi-sensory deficit, ataxia, vertigo, and bulbar dysfunction, but patients presenting with restless legs syndrome (RLS) are extremely rare. Herein, we reported five cases with RLS as a major manifestation of pontine infarction. Methods Five cases of pontine infarction related RLS were collected from July 2013 to February 2016. The diagnosis of RLS was made according to criteria established by the International RLS Study Group (IRLSSG) in 2003. Neurological functions were assessed according to the National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS). Severity of RLS was based on the International RLS Rating Scale (IRLS-RS). Sleep quality was assessed by Epworth Rating Scale (ERS), and individual emotional and psychological states were assessed by Hamilton Depression Scale (HDS) and Hamilton Anxiety Scale (HAS). Results The laboratory data at the onset including hemoglobin, serum concentration of homocysteine, blood urea nitrogen (BUN), creatinine, electrolytes, and thyroid hormones were normal. The electroencephalogram (EEG), lower-extremity somatosensory evoked potential (SEP), and nerve conduction velocity (NCV) in four limbs were normal. The average period of follow-up was 34.60 ± 12.76 months. The MRI examination showed acute or subacute pontine infarction lesions, 3 cases in the rostral inner side, 1 case in the rostral lateral and inner side, and 1 case in rostral lateral side. The neurological deficits included weakness in 4 cases, contralateral sensory deficit in 1 case, and ataxia in 2 cases. All 5 patients presented with symptom of RLS at or soon after the onset of infarction and 4 patients experienced uncomfortable sensations in the paralyzed limbs contralateral to the ischemic lesion. Their neurological deficits improved significantly 2 weeks later, but the symptoms of RLS did not resolve. Among them, 3/5 patients were treated with dopaminergic drugs. At the end of the follow-up, RLS symptom eventually resolved in 3 patients but persisted in two. The IRLS-RS, NIHSS and mRS scores were significantly lower at the onset than those at the last follow-up (P = 0.035, 0.024 and 0.049, respectively). However, there was no significant difference in the ERS, HDS and HAS scores (P = 0.477, 0.226 and 0.778, respectively). Conclusion RLS can be an onset manifestation of pontine infarction, clinicians should be aware of this potential symptom. RLS usually occurs in the paralyzed limbs contralateral to the infarction lesion. The pathogenesis still needs further investigation.
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Affiliation(s)
- Hou-Zhen Tuo
- Department of Neurology, Capital Medical University Affiliated Beijing Friendship Hospital, Beijing 100050, China
| | - Ze-Long Tian
- Department of Neurology, The Fourth Central Hospital of Tianjin, Tianjin 300140, China
| | - Yi-Nong Cui
- Department of Neurology, Capital Medical University Affiliated Beijing Friendship Hospital, Beijing 100050, China
| | - Xiao-Yang Ma
- Department of Neurology, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China
| | - Chun-Ling Xu
- Department of Neurology, Capital Medical University Affiliated Beijing Friendship Hospital, Beijing 100050, China
| | - Hong-Yan Bi
- Department of Neurology, Capital Medical University Affiliated Beijing Friendship Hospital, Beijing 100050, China
| | - Li-Yan Zhang
- Department of Neurology, Capital Medical University Affiliated Beijing Friendship Hospital, Beijing 100050, China
| | - Yong-Bo Zhang
- Department of Neurology, Capital Medical University Affiliated Beijing Friendship Hospital, Beijing 100050, China
| | - Wei-Dong Le
- The Center for Translational Research on Neurological Diseases, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, China
| | - William Ondo
- Department of Neurology, Methodist Neurological Institute, Houston, TX 77030, USA
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Leng ZG, Lin SJ, Wu ZR, Guo YH, Cai L, Shang HB, Tang H, Xue YJ, Lou MQ, Zhao W, Le WD, Zhao WG, Zhang X, Wu ZB. Activation of DRD5 (dopamine receptor D5) inhibits tumor growth by autophagic cell death. Autophagy 2017; 13:1404-1419. [PMID: 28613975 DOI: 10.1080/15548627.2017.1328347] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Dopamine agonists such as bromocriptine and cabergoline have been successfully used in the treatment of pituitary prolactinomas and other neuroendocrine tumors. However, their therapeutic mechanisms are not fully understood. In this study we demonstrated that DRD5 (dopamine receptor D5) agonists were potent inhibitors of pituitary tumor growth. We further found that DRD5 activation increased production of reactive oxygen species (ROS), inhibited the MTOR pathway, induced macroautophagy/autophagy, and led to autophagic cell death (ACD) in vitro and in vivo. In addition, DRD5 protein was highly expressed in the majority of human pituitary adenomas, and treatment of different human pituitary tumor cell cultures with the DRD5 agonist SKF83959 resulted in growth suppression, and the efficacy was correlated with the expression levels of DRD5 in the tumors. Furthermore, we found that DRD5 was expressed in other human cancer cells such as glioblastomas, colon cancer, and gastric cancer. DRD5 activation in these cell lines suppressed their growth, inhibited MTOR activity, and induced autophagy. Finally, in vivo SKF83959 also inhibited human gastric cancer cell growth in nude mice. Our studies revealed novel mechanisms for the tumor suppressive effects of DRD5 agonists, and suggested a potential use of DRD5 agonists as a novel therapeutic approach in the treatment of different human tumors and cancers.
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Affiliation(s)
- Zhi Gen Leng
- a Department of Neurosurgery , First Affiliated Hospital of Wenzhou Medical University , Wenzhou , China
| | - Shao Jian Lin
- b Department of Neurosurgery , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Ze Rui Wu
- a Department of Neurosurgery , First Affiliated Hospital of Wenzhou Medical University , Wenzhou , China
| | - Yu Hang Guo
- a Department of Neurosurgery , First Affiliated Hospital of Wenzhou Medical University , Wenzhou , China
| | - Lin Cai
- a Department of Neurosurgery , First Affiliated Hospital of Wenzhou Medical University , Wenzhou , China
| | - Han Bing Shang
- b Department of Neurosurgery , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Hao Tang
- b Department of Neurosurgery , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Ya Jun Xue
- c Department of Neurosurgery, Shanghai General Hospital , Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Mei Qing Lou
- c Department of Neurosurgery, Shanghai General Hospital , Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Wenxiu Zhao
- e Neuroendocrine Research Laboratory , Massachusetts General Hospital and Harvard Medical School , Boston , MA , USA
| | - Wei-Dong Le
- d Center for Clinical Research on Neurological Diseases , First Affiliated Hospital of Dalian Medical University , Dalian , China
| | - Wei Guo Zhao
- b Department of Neurosurgery , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Xun Zhang
- e Neuroendocrine Research Laboratory , Massachusetts General Hospital and Harvard Medical School , Boston , MA , USA
| | - Zhe Bao Wu
- a Department of Neurosurgery , First Affiliated Hospital of Wenzhou Medical University , Wenzhou , China.,b Department of Neurosurgery , Ruijin Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , China
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Lin SJ, Leng ZG, Guo YH, Cai L, Cai Y, Li N, Shang HB, Le WD, Zhao WG, Wu ZB. Suppression of mTOR pathway and induction of autophagy-dependent cell death by cabergoline. Oncotarget 2016; 6:39329-41. [PMID: 26513171 PMCID: PMC4770775 DOI: 10.18632/oncotarget.5744] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 09/17/2015] [Indexed: 12/19/2022] Open
Abstract
Cabergoline (CAB), the first-line drug for treatment of prolactinomas, is effective in suppressing prolactin hypersecretion, reducing tumor size, and restoring gonadal function. However, mechanisms for CAB-mediated tumor shrinkage are largely unknown. Here we report a novel cytotoxic mechanism for CAB. CAB induced formation of autophagosome in rat pituitary tumor MMQ and GH3 cells at the early stage through inhibiting mTOR pathway, resulting in higher conversion rates of LC3-I to LC3-II, GFP-LC3 aggregation, and increased autophagosome formation. Interestingly, CAB treatment augmented lysosome acidification and resulted in impaired proteolytic degradation within autolysosomes. This blocked the autophagic flux, leading to the accumulation of p62 aggregation and undigested autolysosomes. Knockdown of ATG7, ATG5, or Becn1, could significantly rescue the CAB-mediated cell death of MMQ cells (p < 0.05). CAB-induced autophagy and blockade of autophagy flux participated in antitumoral action in vivo. In conclusion, our study provides evidence that CAB concomitantly induces autophagy and inhibits the autophagic flux, leading to autophagy-dependent cell death. These findings elucidate novel mechanisms for CAB action.
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Affiliation(s)
- Shao Jian Lin
- Department of Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Zhi Gen Leng
- Department of Neurosurgery, First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, China
| | - Yu Hang Guo
- Department of Neurosurgery, First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, China
| | - Lin Cai
- Department of Neurosurgery, First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, China
| | - Yu Cai
- Department of Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Ning Li
- Department of Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Han Bing Shang
- Department of Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Wei-Dong Le
- Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences-Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Wei Guo Zhao
- Department of Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Zhe Bao Wu
- Department of Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
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Dong J, Li S, Mo JL, Cai HB, Le WD. Nurr1-Based Therapies for Parkinson's Disease. CNS Neurosci Ther 2016; 22:351-9. [PMID: 27012974 DOI: 10.1111/cns.12536] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 02/12/2016] [Accepted: 02/12/2016] [Indexed: 12/13/2022] Open
Abstract
Previous studies have documented that orphan nuclear receptor Nurr1 (also known as NR4A2) plays important roles in the midbrain dopamine (DA) neuron development, differentiation, and survival. Furthermore, it has been reported that the defects in Nurr1 are associated with Parkinson's disease (PD). Thus, Nurr1 might be a potential therapeutic target for PD. Emerging evidence from in vitro and in vivo studies has recently demonstrated that Nurr1-activating compounds and Nurr1 gene therapy are able not only to enhance DA neurotransmission but also to protect DA neurons from cell injury induced by environmental toxin or microglia-mediated neuroinflammation. Moreover, modulators that interact with Nurr1 or regulate its function, such as retinoid X receptor, cyclic AMP-responsive element-binding protein, glial cell line-derived neurotrophic factor, and Wnt/β-catenin pathway, have the potential to enhance the effects of Nurr1-based therapies in PD. This review highlights the recent progress in preclinical studies of Nurr1-based therapies and discusses the outlook of this emerging therapy as a promising new generation of PD medication.
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Affiliation(s)
- Jie Dong
- The Center for Translational Research on Neurological Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, China
| | - Song Li
- The Center for Translational Research on Neurological Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, China
| | - Jing-Lin Mo
- The Center for Translational Research on Neurological Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, China
| | - Huai-Bin Cai
- Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Wei-Dong Le
- The Center for Translational Research on Neurological Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, China.,Institute of Health Science, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
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12
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Zhang LM, Sun CC, Mo MS, Cen L, Wei L, Luo FF, Li Y, Li GF, Zhang SY, Yi L, Huang W, Liu ZL, Le WD, Xu PY. Dopamine Agonists Exert Nurr1-inducing Effect in Peripheral Blood Mononuclear Cells of Patients with Parkinson's Disease. Chin Med J (Engl) 2016; 128:1755-60. [PMID: 26112716 PMCID: PMC4733729 DOI: 10.4103/0366-6999.159349] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [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] [Indexed: 11/29/2022] Open
Abstract
Background: Nurr1 plays an essential role in the development, survival, and function maintenance of midbrain dopaminergic (DA) neurons, and it is a potential target for Parkinson's disease (PD). Nurr1 mRNA can be detected in peripheral blood mononuclear cells (PBMCs), but whether there is any association of altered Nurr1 expression in PBMC with the disease and DA drug treatments remains elusive. This study aimed to measure the Nurr1 mRNA level in PBMC and evaluate the effect of Nurr1 expression by DA agents in vivo and in vitro. Methods: The mRNA levels of Nurr1 in PBMC of four subgroups of 362 PD patients and 193 healthy controls (HCs) using real-time polymerase chain reaction were measured. The nonparametric Mann-Whitney U-test and Kruskal-Wallis test were performed to evaluate the differences between PD and HC, as well as the subgroups of PD. Multivariate linear regression analysis was used to evaluate the independent association of Nurr1 expression with Hoehn and Yahr scale, age, and drug treatments. Besides, the Nurr1 expression in cultured PBMC was measured to determine whether DA agonist pramipexole affects its mRNA level. Results: The relative Nurr1 mRNA levels in DA agonists treated subgroup were significant higher than those in recent-onset cases without any anti-PD treatments (de novo) (P < 0.001) and HC groups (P < 0.010), respectively. Furthermore, the increase in Nurr1 mRNA expression was seen in DA agonist and L-dopa group. Multivariate linear regression showed DA agonists, L-dopa, and DA agonists were independent predictors correlated with Nurr1 mRNA expression level in PBMC. In vitro, in the cultured PBMC treated with 10 μmol/L pramipexole, the Nurr1 mRNA levels were significantly increased by 99.61%, 71.75%, 73.16% in 2, 4, and 8 h, respectively (P < 0.001). Conclusions: DA agonists can induce Nurr1 expression in PBMC, and such effect may contribute to DA agonists-mediated neuroprotection on DA neurons.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | - Ping-Yi Xu
- Department of Neurology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong 510080; Department of Neurology, The First Affiliated Hospital of Guangzhou Medical University, Guangdong 510120, China
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13
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Abstract
Objective: Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a progressive, multisystem affected mitochondrial disease associated with a number of disease-related defective genes. MELAS has unpredictable presentations and clinical course, and it can be commonly misdiagnosed as encephalitis, cerebral infarction, or brain neoplasms. This review aimed to update the diagnosis progress in MELAS, which may provide better understanding of the disease nature and help make the right diagnosis as well. Data Sources: The data used in this review came from published peer review articles from October 1984 to October 2014, which were obtained from PubMed. The search term is “MELAS”. Study Selection: Information selected from those reported studies is mainly based on the progress on clinical features, blood biochemistry, neuroimaging, muscle biopsy, and genetics in diagnosing MELAS. Results: MELAS has a wide heterogeneity in genetics and clinical manifestations. The relationship between mutations and phenotypes remains unclear. Advanced serial functional magnetic resonance imaging (MRI) can provide directional information on this disease. Muscle biopsy has meaningful value in diagnosing MELAS, which shows the presence of ragged red fibers and mosaic appearance of cytochrome oxidase negative fibers. Genetic studies have reported that approximately 80% of MELAS cases are caused by the mutation m.3243A>G of the mitochondrial transfer RNA (Leu (UUR)) gene (MT-TL1). Conclusions: MELAS involves multiple systems with variable clinical symptoms and recurrent episodes. The prognosis of MELAS patients depends on timely diagnosis. Therefore, overall diagnosis of MELAS should be based on the maternal inheritance family history, clinical manifestation, and findings from serial MRI, muscle biopsy, and genetics.
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Affiliation(s)
| | - Wei-Dong Le
- Department of Neurology; Center for Translational Research of Neurology Disease, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, China
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14
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Zhu MZ, Le WD, Jin G. Ropinirole alters gene expression profiles in SH-SY5Y cells: a whole genome microarray study. Braz J Med Biol Res 2016; 49:e4857. [PMID: 26785691 PMCID: PMC4725189 DOI: 10.1590/1414-431x20154857] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 09/01/2015] [Indexed: 11/25/2022] Open
Abstract
Ropinirole (ROP) is a dopamine agonist that has been used as therapy for Parkinson's
disease. In the present study, we aimed to detect whether gene expression was
modulated by ROP in SH-SY5Y cells. SH-SY5Y cell lines were treated with 10 µM ROP for
2 h, after which total RNA was extracted for whole genome analysis. Gene expression
profiling revealed that 113 genes were differentially expressed after ROP treatment
compared with control cells. Further pathway analysis revealed modulation of the
phosphatidylinositol 3-kinase (PI3K) signaling pathway, with prominent upregulation
of PIK3C2B. Moreover, batches of regulated genes, including
PIK3C2B, were found to be located on chromosome 1. These findings
were validated by quantitative RT-PCR and Western blot analysis. Our study,
therefore, revealed that ROP altered gene expression in SH-SY5Y cells, and future
investigation of PIK3C2B and other loci on chromosome 1 may provide
long-term implications for identifying novel target genes of Parkinson's disease.
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Affiliation(s)
- M Z Zhu
- School of Public Health, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - W D Le
- Shanghai Institutes for Biological Sciences, Institute of Health Sciences, Chinese Academy of Science/Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - G Jin
- Shanghai Institutes for Biological Sciences, Institute of Health Sciences, Chinese Academy of Science/Shanghai Jiao Tong University School of Medicine, Shanghai, China
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15
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Cai ZX, Guo HS, Wang C, Wei M, Cheng C, Yang ZF, Chen YW, Le WD, Li S. Double-Edged Roles of Nitric Oxide Signaling on APP Processing and Amyloid-β Production In Vitro: Preliminary Evidence from Sodium Nitroprusside. Neurotox Res 2015; 29:21-34. [PMID: 26429731 DOI: 10.1007/s12640-015-9564-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 09/02/2015] [Accepted: 09/22/2015] [Indexed: 11/27/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder that is thought to be caused in part by the age-related accumulation of amyloid-β (Aβ) in the brain. Recent findings have revealed that nitric oxide (NO) modulates the processing of amyloid-β precursor protein (APP) and alters Aβ production; however, the previously presented data are contradictory and the underlying molecular mechanisms are still incomplete. Here, using human SH-SY5Y neuroblastoma cells stably transfected with wild-type APPwt695, we found that NO, derived from NO donor sodium nitroprusside (SNP), bi-directionally modulates APP processing in vitro. The data from ELISA and Western blot (WB) tests indicated that SNP at lower concentrations (0.01 and 0.1 μM) inhibits BACE1 expression, thus consequently suppresses APP β-cleavage and decreases Aβ production. In contrast, SNP at higher concentrations (10 and 20 μM) biases the APP processing toward the amyloidogenic pathway as evidenced by an increased BACE1 but a decreased ADAM10 expression, together with an elevated Aβ secretion. This bi-directional modulating activity of SNP on APP processing was completely blocked by specific NO scavenger c-PTIO, indicating NO-dependent mechanisms. Moreover, the anti-amyloidogenic activity of SNP is sGC/cGMP/PKG-dependent as evidenced by its reversal by sGC/PKG inhibitions, whereas the amyloidogenic activity of SNP is peroxynitrite-related and can be reversed by peroxynitrite scavenger uric acid. In summary, these present findings predict a double-edged role of NO in APP processing in vitro. Low (physiological) levels of NO inhibit the amyloidogenic processing of APP, whereas extra-high (pathological) concentrations of NO favor the amyloidogenic pathway of APP processing. This preliminary study may provide further evidence to clarify the molecular roles of NO and NO-related signaling in AD and supply potential molecular targets for AD treatment.
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Affiliation(s)
- Zheng-Xu Cai
- Department of Neurology, The First Affiliated Hospital of Dalian Medical University, Dalian, 116011, China
| | - Hui-Shu Guo
- Laboratory Center, The First Affiliated Hospital of Dalian Medical University, Dalian, 116011, China
| | - Che Wang
- Department of Pharmacy, School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian, 116029, China.,Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, School of Life Sciences, Liaoning Normal University, Dalian, 116029, China
| | - Min Wei
- Center for Translational Research on Neurological Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, 116011, China
| | - Cheng Cheng
- Center for Translational Research on Neurological Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, 116011, China
| | - Zhao-Fei Yang
- Center for Translational Research on Neurological Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, 116011, China
| | - Yin-Wang Chen
- Department of Pharmacy, School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian, 116029, China
| | - Wei-Dong Le
- Center for Translational Research on Neurological Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, 116011, China.
| | - Song Li
- Center for Translational Research on Neurological Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, 116011, China.
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16
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Le WD. Frontier in Neurology Research Beyond Neurodegenerative Diseases. Chin Med J (Engl) 2015; 128:1705-6. [PMID: 26112707 PMCID: PMC4733721 DOI: 10.4103/0366-6999.159334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Wei-Dong Le
- Department of Neurology and Center for Translational Research of Neurology Disease, 1st Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116011, China
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17
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Chen JW, Zhao L, Zhang F, Li L, Gu YH, Zhou JY, Zhang H, Meng M, Zhang KH, Le WD, Dong CB. Clinical Characteristics, Radiological Features and Gene Mutation in 10 Chinese Families with Spinocerebellar Ataxias. Chin Med J (Engl) 2015; 128:1714-23. [PMID: 26112709 PMCID: PMC4733707 DOI: 10.4103/0366-6999.159340] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [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] [Indexed: 12/29/2022] Open
Abstract
Background: Spinocerebellar ataxias (SCAs) are a group of neurodegenerative disorders that primarily cause the degeneration in the cerebellum, spinal cord, and brainstem. We study the clinical characteristics, radiological features and gene mutation in Chinese families with SCAs. Methods: In this study, we investigated 10 SCAs Chinese families with SCA1, SCA3/Machado–Joseph disease (MJD), SCA7, SCA8. There were 27 people who were genetically diagnosed as SCA, of which 21 people showed clinical symptoms, and 6 people had no clinical phenotype that we called them presymptomatic patients. In addition, 3 people with cerebellar ataxia and cataracts were diagnosed according to the Harding diagnostic criteria but failed to be recognized as SCAs on genetic testing. Clinical characteristic analyses of each type of SCAs and radiological examinations were performed. Results: We found that SCA3/MJD was the most common subtype in Han population in China, and the ratio of the pontine tegmentum and the posterior fossa area was negatively correlated with the number of cytosine-adenine-guanine (CAG) repeats; the disease duration was positively correlated with the International Cooperative Ataxia Rating Scale score; and the CAG repeats number of abnormal alleles was negatively correlated with the age of onset. Conclusions: Collectively our study is a systematic research on SCAs in China, which may help for the clinical diagnosis and prenatal screening of this disease, and it may also aid toward better understanding of this disease.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Chun-Bo Dong
- Department of Neurology, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, China
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18
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Chen S, Zhang XJ, Xie WJ, Qiu HY, Liu H, Le WD. A New VMAT-2 Inhibitor NBI-641449 in the Treatment of Huntington Disease. CNS Neurosci Ther 2015; 21:662-71. [PMID: 26122704 DOI: 10.1111/cns.12425] [Citation(s) in RCA: 6] [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: 10/06/2014] [Revised: 05/22/2015] [Accepted: 05/24/2015] [Indexed: 12/20/2022] Open
Abstract
AIMS To evaluate the effectiveness of a new VMAT-2 inhibitor NBI-641449 in controlling hyperkinetic movements of Huntington disease (HD) and to investigate its possible therapeutic effects. METHODS We applied three different doses of NBI-641449 (1, 10, 100 mg/kg/day) for 2 weeks in 4-month-old YAC128 mice and wild-type (WT) mice. Rotarod performance and locomotive activities were tested during the administration of the drug. The concentration of dopamine (DA) and its metabolites was quantified in the striatal tissues by high-performance liquid chromatography (HPLC). Neuron survival in striatum and huntingtin protein aggregates were assessed with immunostaining. Expression levels of endoplasmic reticulum (ER) stress proteins were detected by immunoblotting. RESULTS Rotarod performance was significantly improved after treatment with low or middle dose of NBI-641449 in YAC128 mice. Open field test showed that NBI-641449 treatment could attenuate the increased horizontal activity (HACTV), total vertical movement, moving time, and moving distance in YAC128 mice. High dose of NBI-641449 might cause sedative effects in WT and YAC128 mice. HPLC showed that NBI-641449 caused a dose-dependent decrease of DA, 3,4-dihydroxyphenylacetic acid, and homovanillic acid levels in the striatum. NeuN and DARPP-32 immunostaining revealed that NBI-641449 had no significant effect on the neuron survival in the striatum. However, NBI-641449 treatment reduced the huntingtin protein aggregates in the cortex of YAC128 mice. In addition, the levels of ER stress proteins were increased in YAC128 mice, which can be suppressed by NBI-641449. CONCLUSIONS These findings suggest that this new VMAT-2 inhibitor NBI-641449 may have therapeutic potential for the treatment of HD.
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Affiliation(s)
- Sheng Chen
- Institute of Neurology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.,Department of Neurology, Baylor College of medicine, Houston, TX, USA
| | - Xiao-Jie Zhang
- Institute of Neurology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Wen-Jie Xie
- Diana Helis Henry Medical Research Foundation, New Orleans, LA, USA
| | - Hong-Yan Qiu
- Institute of Neurology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Hui Liu
- Institute of Neurology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Wei-Dong Le
- Institute of Neurology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.,Center for Translational Research of Neurology Diseases, The First Affiliated Hospital, Dalian Medical University, Dalian, China
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19
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Shao BY, Xia Z, Xie Q, Ge XX, Zhang WW, Sun J, Jiang P, Wang H, Le WD, Qiu ZB, Lu Y, Chen HZ. Meserine, a novel carbamate AChE inhibitor, ameliorates scopolamine-induced dementia and alleviates amyloidogenesis of APP/PS1 transgenic mice. CNS Neurosci Ther 2013; 20:165-71. [PMID: 24279603 DOI: 10.1111/cns.12183] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [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: 05/23/2013] [Revised: 09/09/2013] [Accepted: 09/09/2013] [Indexed: 11/27/2022] Open
Abstract
AIMS To investigate whether Meserine, a novel phenylcarbamate derivative of (-)-meptazinol, possesses beneficial activities against cholinergic deficiency and amyloidogenesis, the two major pathological characteristics of Alzheimer's disease (AD). METHODS Ellman's assay and Morris water maze were used to detect acetylcholinesterase (AChE) activity and evaluate spatial learning and memory ability, respectively. Both high content screening and Western blotting were carried out to detect β-amyloid precursor protein (APP), while RT-PCR and ELISA were conducted to detect APP-mRNA and β-amyloid peptide (Aβ). RESULTS In scopolamine-induced dementia mice, Meserine (1 mg/kg, i.p.) significantly ameliorated spatial learning and memory deficits, which was consistent with its in vitro inhibitory ability against AChE (recombinant human AChE, IC50 = 274 ± 49 nM). Furthermore, Meserine (7.5 mg/kg) injected intraperitoneally once daily for 3 weeks lowered APP level by 28% and Aβ42 level by 42% in APP/PS1 transgenic mouse cerebrum. This APP modulation action might be posttranscriptional, as Meserine reduced APP by about 30% in SH-SY5Y-APP695 cells but did not alter APP-mRNA level. And both APP and Aβ42 lowering action of Meserine maintained longer than that of rivastigmine. CONCLUSION Meserine executes dual actions against cholinergic deficiency and amyloidogenesis and provides a promising lead compound for symptomatic and modifying therapy of AD.
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Affiliation(s)
- Bi-Yun Shao
- Department of Pharmacology & Chemical Biology, Institute of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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20
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Abstract
Type II DNA topoisomerases (Tops) are ATP-dependent enzymes that catalyze topological transformations of genomic DNA by the transport of one DNA double helix through another. In mammals, there are 2 isoforms of DNA Top II, termed Top IIα and Top IIβ. The IIβ isoform is abundantly expressed in cells that have undergone the final cell division and are committed to differentiation into neuronal cells. In recent years, there have been accumulating studies showing the significant role of Top IIβ in neuronal development through regulating expression of certain genes in cells committed to the neuronal fate after the final division. These genes are involved in the processes of neuronal differentiation, migration, axon guidance and so on. The present review mainly focused on the research progress on the role of Top IIβ in neuronal development over the recent decades.
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Affiliation(s)
- Xin Heng
- Institute of Health Science, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and Shanghai Jiao Tong University School of Medicine, Ruijin Hospital, Shanghai 200025, China
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21
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Guo Y, Le WD, Jankovic J, Yang HR, Xu HB, Xie WJ, Song Z, Deng H. Systematic genetic analysis of the PITX3
gene in patients with Parkinson disease. Mov Disord 2011; 26:1729-32. [DOI: 10.1002/mds.23693] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2010] [Revised: 01/17/2011] [Accepted: 02/01/2011] [Indexed: 11/06/2022] Open
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22
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Lau YS, Patki G, Das-Panja K, Le WD, Ahmad SO. Neuroprotective effects and mechanisms of exercise in a chronic mouse model of Parkinson's disease with moderate neurodegeneration. Eur J Neurosci 2011; 33:1264-74. [PMID: 21375602 DOI: 10.1111/j.1460-9568.2011.07626.x] [Citation(s) in RCA: 180] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The protective impact of exercise on neurodegenerative processes has not been confirmed, and the mechanisms underlying the benefit of exercise have not been determined in human Parkinson's disease or in chronic animal disease models. This research examined the long-term neurological, behavioral, and mechanistic consequences of endurance exercise in experimental chronic parkinsonism. We used a chronic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of Parkinson's disease with moderate neurodegeneration and examined the effects of treadmill exercise on movement and balance coordination, changes in dopamine neuron biomarkers, mitochondrial functions, and neurotrophic factor activities in the nigrostriatal system. The exercise results were compared with those of the control and sedentary chronic parkinsonian animals. After 18 weeks of exercise training in the chronic parkinsonian mice, we observed a significant deterrence in the loss of neuronal dopamine-producing cells and other functional indicators. The impaired movement and balance incoordination in the chronic parkinsonian mice were also markedly reduced following exercise. Mechanistic investigations revealed that the neuronal and behavioral recovery produced by exercise in the chronic parkinsonian mice was associated with an improved mitochondrial function and an increase in the brain region-specific levels of brain-derived and glial cell line-derived neurotrophic factors. Our findings indicate that exercise not only produces neuronal and mitochondrial protection, it also boosts nigrostriatal neurotrophic factor levels in the chronic parkinsonian mice with moderate neurodegeneration. Therefore, modifying lifestyle with increased exercise activity would be a non-pharmacological neuroprotective approach for averting neurodegenerative processes, as demonstrated in experimental chronic parkinsonism.
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Affiliation(s)
- Yuen-Sum Lau
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX 77204, USA.
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23
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Tan EK, Peng R, Teo YY, Tan LC, Angeles D, Ho P, Chen ML, Lin CH, Mao XY, Chang XL, Prakash KM, Liu JJ, Au WL, Le WD, Jankovic J, Burgunder JM, Zhao Y, Wu RM. Multiple LRRK2 variants modulate risk of Parkinson disease: a Chinese multicenter study. Hum Mutat 2010; 31:561-8. [PMID: 20186690 DOI: 10.1002/humu.21225] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We and others found two polymorphic LRRK2 (leucine-rich repeat kinase 2) variants (rs34778348:G>A; p.G2385R and rs33949390:G>C; p.R1628P) associated with Parkinson disease (PD) among Chinese patients, but the common worldwide rs34637584:G>A; p.G2019S mutation, was absent. Focusing exclusively on Han Chinese, we first sequenced the coding regions in young onset and familial PD patients and identified 59 variants. We then examined these variants in 250 patients and 250 control subjects. Among the 17 polymorphic variants, five demonstrated different frequency in cases versus controls and were considered in a larger sample of 1,363 patients and 1,251 control subjects. The relative risk of an individual with both p.G2385R and p.R1628P is about 1.9, and this is reduced to 1.5-1.6 if the individual also carries rs7133914:G>C; p.R1398H or rs7308720:C>A: p.N551K. The risk of a carrier with p.R1628P is largely negated if the individual also carries p.R1398H or p.N551K. In dopaminergic neuronal lines, p.R1398H had significantly lower kinase activity, whereas p.G2385R and p.R1628P showed higher kinase activity than wild type. We provided the first evidence that multiple LRRK2 variants exert an individual effect and together modulate the risk of PD among Chinese.
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Affiliation(s)
- Eng-King Tan
- Departments of Neurology, Singapore General Hospital, Singapore
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24
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Chen S, Zhang XJ, Li L, Le WD. Current experimental therapy for Alzheimer's disease. Curr Neuropharmacol 2010; 5:127-34. [PMID: 18615180 DOI: 10.2174/157015907780866901] [Citation(s) in RCA: 10] [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: 10/06/2006] [Revised: 12/14/2006] [Accepted: 01/18/2007] [Indexed: 12/14/2022] Open
Abstract
In the past decade, enormous efforts have been devoted to understand the genetics and molecular pathogenesis of Alzheimer's disease (AD), which has been transferred into extensive experimental approaches aimed at reversing disease progression. The trend in future AD therapy has been shifted from traditional anti-acetylcholinesterase treatment to multiple mechanisms-based therapy targeting amyloid plaques formation and amyloid peptides (Abeta)-mediated cytotoxicity, and neurofibrillary tangles generation. This review will cover current experimental studies with the focus on secretases-based drug development, immunotherapy, and anti-neurofibrillary tangles intervention. The outcome of these on-going studies may provide high hope that AD can be cured in the future.
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Affiliation(s)
- Sheng Chen
- Institutes of Neurology, Ruijin Hospital, Jiao Tong University School of Medicine, Shanghai, China
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25
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Abstract
BACKGROUND Several genetic variants in transcription factor genes have been reported to be associated with Parkinson's disease (PD). The muscle segment homeobox drosophila homolog of 1 gene (MSX1) is a major upstream regulator of the dopaminergic neuronal subtype specification. AIMS OF THE STUDY To determine whether genetic variation in the coding region of the MSX1 gene plays a role in the etiology of PD. METHODS We searched for genetic variations in the coding region of the MSX1 gene in 202 patients with PD and 200 normal controls by PCR-single-strand conformation polymorphism (PCR-SSCP) and sequencing. RESULTS No mutation in the MSX1 gene was identified in our cohort. CONCLUSIONS Mutations in the coding region of the MSX1 gene play little or no role in the development of PD.
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Affiliation(s)
- H Deng
- Center for Experimental Medicine, the Third Xiangya Hospital, Central South University, China
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26
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Wang YM, Pu P, Le WD. ATP depletion is the major cause of MPP+ induced dopamine neuronal death and worm lethality in alpha-synuclein transgenic C. elegans. Neurosci Bull 2008; 23:329-35. [PMID: 18064062 DOI: 10.1007/s12264-007-0049-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE To investigate the toxic effect of environmental neurotoxin MPP+ to C. elegans and identify the mechanisms that cause the toxicity. METHODS Human alpha-synuclein transgenic C. elegans was used as the animal model, the toxic effect of MPP+ to dopamine (DA) neurons and the lifespan of worms was tested. The worms were feed with OP50 to determine whether ATP increase can rescue the worm from toxicity. ATP level and aberrant protein accumulation were analyzed in the MPP+ treated worms with or without OP50 addition. RESULTS We found that MPP+ induced DA cell death and worm lethality, which could be prevented by OP50 treatment. OP50 exerted the protective effect by up-regulating ATP level, even though it also induced accumulation of alpha-synuclein. Despite the undefined role of protein aggregation to the cell death, our results showed that the toxicity of MPP+ was mainly caused by the ATP depletion in the alpha-synuclein transgenic C. elegans. CONCLUSION MPP+ could induce DA neuronal death and worm lethality in alpha-synuclein transgenic C. elegans; Compared with the aggregation of alpha-synuclein, the major cause of MPP+ toxicity appeared due to ATP depletion.
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Affiliation(s)
- Yi-Min Wang
- Neural Genomics Laboratory, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences/Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
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27
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Abstract
Restless legs syndrome (RLS) is a common disease with prevalence up to 10% in the general population. It is mostly a subjective condition, making animal models intrinsically difficult. General increased activity (urge to move) and limb movements consistent with periodic limb movements of sleep, seen in most patients with RLS, are currently our best behavioral markers. Our best understanding of human RLS demonstrates reduced central nervous system (CNS) iron stores and dysfunction of dopaminergic systems, which most likely involves the spinal cord. Based upon this knowledge, animal manipulations, including destruction of the A11 diencephalic-spinal tract and iron deprivation, have resulted in animal behavior consistent with RLS. Dopamine receptor type 3 knockout mice also show general increased activity. Pharmacologic blockade of dopamine receptors in rodents has also caused movements resembling periodic limb movements of sleep in older rodents but not in younger animals. More sophisticated animal modeling is needed to facilitate our understanding of RLS.
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Affiliation(s)
- W G Ondo
- Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA.
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28
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Abstract
BACKGROUND Mutations in the parkin gene cause autosomal recessive early-onset Parkinson disease (EOPD). The A265G variant in the HS1 binding protein 3 gene (HS1BP3) is common in essential tremor (ET). OBJECTIVE To investigate the presence of mutations in the parkin gene and the A265G variant in the HS1BP3 gene in a Mexican family with EOPD, ET, and Bell palsy. DESIGN Direct sequencing, semiquantitative polymerase chain reaction, and reverse transcription-polymerase chain reaction were performed in the 14 members of this family. SETTING Mexican family. Patients Two patients with EOPD were analyzed. RESULTS Compound heterozygous mutations (EX 3_6 del and EX 5 del) in the parkin gene were identified in 2 patients with EOPD, characterized by beneficial response to levodopa, relatively slow progression, and motor complications. Although heterozygous EX 3_6 del and homozygous EX 5 del mutations in the parkin gene have been previously described, to our knowledge, this is the first report of these mutations in compound heterozygotes. Seven heterozygous A265G variants in the HS1BP3 gene were found in this pedigree, but they did not cosegregate with ET, Parkinson disease, or Bell palsy, supporting the conclusion that this variant is not associated with ET. CONCLUSIONS Compound heterozygous parkin mutations (EX 3_6 del and EX 5 del) caused EOPD in this family, but the A265G variant in the HS1BP3 gene, previously considered to be responsible for ET, was probably not pathogenically related to the ET in this family.
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Affiliation(s)
- Hao Deng
- Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA
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29
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Abstract
OBJECTIVE To determine whether variants in the Slit and Trk-like 1 gene (SLITRK1) are present in American Caucasian population of patients with Tourette syndrome (TS). METHODS We sequenced the 3'-untranslated region for var321 and the whole coding region in the SLITRK1 gene in 82 Caucasian patients with TS from North America. RESULTS None of the 82 samples from patients with TS showed the non-coding sequence variant (var321). Only one patient with familial TS was heterozygous for a novel 708C > T (Ile236Ile) nucleotide variant. CONCLUSIONS The var321 and mutation(s) in the coding region of the SLITRK1 gene probably are a rare cause of TS in a Caucasian population; therefore, genetic heterogeneity of TS should be considered. Tests designed to detect variant(s) in the SLITRK1 gene probably will not have a diagnostic utility in clinical practice.
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Affiliation(s)
- H Deng
- Department of Neurology, Parkinson's Disease Center and Movement Disorders Clinic, Baylor College of Medicine, Houston, TX 77030, USA
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30
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Deng H, Le W, Guo Y, Hunter CB, Xie W, Huang M, Jankovic J. Genetic analysis of LRRK2 mutations in patients with Parkinson disease. J Neurol Sci 2006; 251:102-6. [PMID: 17097110 DOI: 10.1016/j.jns.2006.09.017] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2006] [Revised: 08/07/2006] [Accepted: 09/11/2006] [Indexed: 11/19/2022]
Abstract
In addition to the G2019S mutation in the leucine-rich repeat kinase 2 gene (LRRK2), which is particularly frequent in patients of Ashkenazi Jewish and Northern African origin, three amino acid substitutions (R1441C, R1441G, and R1441H), all at the same residue (R1441), have been identified as important genetic causes of Parkinson disease (PD). To evaluate the frequency of R1441C/G/H and G2019S mutations in the LRRK2 gene in North American patients with PD and to explore genotype-phenotype correlations, we screened 496 PD patients from North America. One Hispanic female was heterozygous for the LRRK2 R1441G mutation, and six other cases including 2 non-Jewish/non-Hispanic whites, 3 Ashkenazi Jewish, and 1 Hispanic, were found to be heterozygous for the LRRK2 G2019S mutation. G2019S mutation in the LRRK2 gene is a common mutation associated with PD in a North American population, especially in Jewish PD patients (10.7%), while the R1441C/G/H mutation occurs at a relatively low frequency in North Americans except possibly in Hispanics for R1441G. All six G2019S carriers shared a common haplotype with that observed in Europeans and North Africans. The clinical features of all seven cases with LRRK2 mutation were quite broad and included early and late disease onset. These finding may provide new insights into the cause and diagnosis of PD and have implications for genetic counseling.
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Affiliation(s)
- Hao Deng
- Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA
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31
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Abstract
Heat shock proteins (HSPs), known as molecular chaperone to assist protein folding, have recently become a research focus in Parkinson's disease (PD) because the pathogenesis of this disease is highlighted by the intracellular protein misfolding and inclusion body formation. The present review will focus on the functions of different HSPs and their protective roles in PD. It is postulated that HSPs may serve as protein folding machinery and work together with ubiquitin-proteasome system (UPS) to assist in decomposing aberrant proteins. Failure of UPS is thought to play a key role in the pathogenesis of PD. In addition, HSPs may possess anti-apoptotic effects and keep the homeostasis of dopaminergic neurons against stress conditions. The critical role of HSPs and recent discovery of some novel HSPs inducers suggest that HSPs may be potential therapeutic targets for PD and other neurodegenerative disorders.
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Affiliation(s)
- Guang-Rui Luo
- Institute of Health Sciences, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai, China
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Deng H, Le W, Davidson AL, Xie W, Jankovic J. The LRRK2 I2012T, G2019S and I2020T mutations are not common in patients with essential tremor. Neurosci Lett 2006; 407:97-100. [PMID: 16939701 DOI: 10.1016/j.neulet.2006.08.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2006] [Revised: 08/03/2006] [Accepted: 08/07/2006] [Indexed: 10/24/2022]
Abstract
Several mutations in the leucine-rich repeat kinase 2 gene (LRRK2) have been identified both in familial and sporadic cases of Parkinson's disease (PD). G2019S, located at a kinase (MAPKKK) domain, is the most common mutation in the LRRK2 gene in PD, Two adjacent mutations (I2012T and I2020T) were mapped to the same domain suggesting shared pathogenic mechanism of these mutations. Since phenotypes of PD overlap with essential tremor (ET), we investigated LRRK2 G2019S, I2012T, and I2020T mutations in a cohort of 272 patients with ET. No mutations were found in our ET cohort and, therefore, we conclude that LRKK2 I2012T, G2019S and I2020T variants are rare causes of Caucasian ET.
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Affiliation(s)
- Hao Deng
- Department of Neurology, Baylor College of Medicine, 6550 Fannin, Suite 1801, Houston, TX 77030, USA
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33
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Li R, Peng N, Li XP, Le WD. (-)-Epigallocatechin gallate regulates dopamine transporter internalization via protein kinase C-dependent pathway. Brain Res 2006; 1097:85-9. [PMID: 16733047 DOI: 10.1016/j.brainres.2006.04.071] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2006] [Revised: 04/18/2006] [Accepted: 04/23/2006] [Indexed: 01/12/2023]
Abstract
Dopamine transporter (DAT) provides not only an integral component of dopaminergic neurotransmission but also a molecular gateway for the accumulation of some neurotoxins such as 1-methyl-4-phenylpyridinium (MPP(+)), a metabolite of 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine (MPTP). Previous study reported that the neuroprotective effects of green tea polyphenols against MPP(+)-induced neurotoxicity were related to its inhibitory effect on MPP(+) uptake via DAT in dopaminergic cells. To extend the study, we investigated (-)-epigallocatechin gallate (EGCG), a monomer of green tea polyphenols, on DAT internalization in DAT-overexpressed PC12 cells. We found that EGCG (1-100 microM) can induce a dose-dependent inhibition of dopamine uptake in DAT-PC12 cells. In parallel, treatment of EGCG decreased membrane-bound DAT by 15% to 60%. Furthermore, protein kinase C (PKC) inhibitor GF109203X at 2 microM can markedly diminish the inhibitory effects of EGCG on dopamine uptake and reverse the EGCG-induced internalization of DAT. In addition, semiquantitative RT-PCR analysis indicated that EGCG did not affect DAT mRNA expression in the PC12 cells. These data suggest that EGCG exerts its inhibitory effect on DAT by modulating DAT internalization, in which PKC activation may be involved.
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Affiliation(s)
- Rui Li
- Joint Laboratory of Institute of Health Science, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, and State Key Laboratory of Medical Genomics, Ruijin Hospital, Jiao Tong University School of Medicine, Shanghai 200025, P R China
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34
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Deng H, Xie WJ, Le WD, Huang MS, Jankovic J. Genetic analysis of the GABRA1 gene in patients with essential tremor. Neurosci Lett 2006; 401:16-9. [PMID: 16530959 DOI: 10.1016/j.neulet.2006.02.066] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Revised: 02/20/2006] [Accepted: 02/22/2006] [Indexed: 11/22/2022]
Abstract
The gamma-aminobutyric acid A (GABA-A) receptor mediates inhibitory neurotransmission in the brain and as such may be involved in certain neurological movement disorders, such as tremor. GABA-A receptor alpha 1 (Gabra)(-/-) mice have been reported to exhibit postural and kinetic, alcohol-responsive, tremor that is characteristic of essential tremor (ET), the most common form of tremor. To determine whether ET is associated with the GABRA1 gene mutation, we screened 76 patients with familial ET and found a novel nucleotide variant: IVS8+24 G>T (nt 6119289) in a male patient, and a known 156T>C polymorphism (nt 6090903) in exon 4 in 41% patients, which results in a silent mutation (G52G). No significant association between 156T>C variant and disease risk was found (adjusted OR=0.95, 95% CI=0.57-1.61; p=0.858) by further analysis of 121 familial ET patients and 114 normal controls, except a novel 96A>G (Q32Q; nt 6090743) variant, found in a normal control. Since the 156T>C variant appears to be not pathogenically relevant, our results suggest that missense, nonsense or splice site mutation in the coding region of the GABRA1 gene is not a major genetic cause of ET in Caucasian subjects.
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Affiliation(s)
- Hao Deng
- Department of Neurology, Baylor College of Medicine, 6501 Fannin Street, Houston, TX 77030, USA
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35
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Imam SZ, Jankovic J, Ali SF, Skinner JT, Xie W, Conneely OM, Le WD. Nitric oxide mediates increased susceptibility to dopaminergic damage in Nurr1 heterozygous mice. FASEB J 2006; 19:1441-50. [PMID: 16126911 DOI: 10.1096/fj.04-3362com] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Knocking out of Nurr1 gene, a member of nuclear receptor superfamily, causes selective agenesis of dopaminergic neurons in midbrain. Reduced expression of Nurr1 increases the vulnerability of mesencephalic dopamine neurons to dopaminergic toxins. We evaluated the role of nitric oxide as a possible mechanism for this increased susceptibility. Increased expression of neuronal nitric oxide synthase and increased 3-nitrotyrosine were observed in striatum of Nurr1 heterozygous (Nurr1 +/-) mice as compared with wild-type. Increased cytochrome C activation and consecutive release of Smac/DIABLO were also observed in Nurr1 +/- mice. An induction of active Caspase-3 and p53, cleavage of poly-ADP (RNase) polymerase and reduced expression of bcl-2 were observed in Nurr1 +/- mice. Methamphetamine significantly increased these markers in Nurr1 +/- mice as compared with wild-type. The present data therefore suggest that nitric oxide plays a role as a modulating factor for the increased susceptibility, but not the potentiation, of the dopaminergic terminals in Nurr1 +/- mice. We also report that this increased neuronal nitric oxide synthase expression and increased nitration in Nurr1 +/- mice led to the activation of apoptotic cascade via the differential alterations in the DNA binding activity of transcription factors responsible for the propagation of growth arrest as well as apoptosis.
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Affiliation(s)
- Syed Z Imam
- South Texas Veteran Health Care System and Department of Medicine of UT Health Science, San Antonio, Texas, USA.
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36
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Deng H, Le WD, Hunter CB, Ondo WG, Guo Y, Xie WJ, Jankovic J. Heterogeneous phenotype in a family with compound heterozygous parkin gene mutations. ACTA ACUST UNITED AC 2006; 63:273-7. [PMID: 16476817 DOI: 10.1001/archneur.63.2.273] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND Mutations in the parkin gene (PRKN) cause autosomal recessive early-onset Parkinson disease (EOPD). OBJECTIVE To investigate the presence of mutations in the PRKN gene in a white family with EOPD and the genotype-phenotype correlations. DESIGN Twenty members belonging to 3 generations of the EOPD family with 4 affected subjects underwent genetic analysis. Direct genomic DNA sequencing, semiquantitative polymerase chain reaction, real-time quantitative polymerase chain reaction, and reverse-transcriptase polymerase chain reaction analyses were performed to identify the PRKN mutation. RESULTS Compound heterozygous mutations (T240M and EX 5_6 del) in the PRKN gene were identified in 4 patients with early onset (at ages 30-38 years). Although heterozygous T240M and homozygous EX 5_6 del mutations in the PRKN gene have been previously described, this is, to our knowledge, the first report of these mutations in compound heterozygotes. The phenotype of patients was that of classic autosomal recessive EOPD characterized by beneficial response to levodopa, relatively slow progression, and motor complications. All heterozygous mutation carriers (T240M or EX 5_6 del) and a 56-year-old woman who was a compound heterozygous mutation carrier (T240M and EX 5_6 del) were free of any neurological symptoms. CONCLUSIONS Compound heterozygous mutations (T240M and EX 5_6 del) in the PRKN gene were found to cause autosomal recessive EOPD in 4 members of a large white family. One additional member with the same mutation, who is more than 10 years older than the mean age at onset of the 4 affected individuals, had no clinical manifestation of the disease. This incomplete penetrance has implications for genetic counseling, and it suggests that complex gene-environment interactions may play a role in the pathogenesis of PRKN EOPD.
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Affiliation(s)
- Hao Deng
- Department of Neurology, Baylor College of Medicine, Houston, Tex 77030, USA
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37
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Li XP, Le WD. [Application of single cell gene expression analysis techniques on neurosciences research]. Sheng Li Ke Xue Jin Zhan 2006; 37:55-7. [PMID: 16683548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
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38
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Jankovic J, Chen S, Le WD. The role of Nurr1 in the development of dopaminergic neurons and Parkinson's disease. Prog Neurobiol 2005; 77:128-38. [PMID: 16243425 DOI: 10.1016/j.pneurobio.2005.09.001] [Citation(s) in RCA: 242] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2005] [Revised: 07/22/2005] [Accepted: 09/13/2005] [Indexed: 11/25/2022]
Abstract
Nurr1, a transcription factor belonging to the orphan nuclear receptor superfamily, is critical in the development and maintenance of the dopaminergic system and as such it may have role in the pathogenesis of Parkinson' disease (PD). Human Nurr1 gene has been mapped to chromosome 2q22-23 and Nurr1 protein is predominantly expressed in central dopaminergic neurons. Nurr1 interacts with other factors critical for the survival of mensencephalic dopaminergic neurons and it appears to regulate the expression of tyrosine hydroxylase (TH), dopamine transporter (DAT), vesicular monoamine transporter 2 (VMAT2), and l-aromatic amino acid decarboxylase (AADC), all of which are important in the synthesis and storage of dopamine. Experimental studies in Nurr1 knock-out mice indicate that Nurr1 deficiency results in impaired dopaminergic function and increased vulnerability of those midbrain dopaminergic neurons that degenerate in PD. Decreased Nurr1 expression is found in the autopsied PD midbrains, particularly in neurons containing Lewy bodies, as well as in peripheral lymphocytes of patients with parkinsonian disorders. Several variants in Nurr1 gene have been reported in association with PD. All these studies suggest that Nurr1 is not only essential in the development of mensencephalic dopaminergic neurons and maintenance of their functions, but it may also play a role in the pathogenesis of PD.
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Affiliation(s)
- J Jankovic
- Department of Neurology, Parkinson Disease Research Lab, Baylor College of Medicine, Houston, TX 77030, USA
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39
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Affiliation(s)
- H Deng
- Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA
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40
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Qu S, Ondo WG, Zhang X, Xie WJ, Pan TH, Le WD. Projections of diencephalic dopamine neurons into the spinal cord in mice. Exp Brain Res 2005; 168:152-6. [PMID: 16044299 DOI: 10.1007/s00221-005-0075-1] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2004] [Accepted: 05/24/2005] [Indexed: 10/25/2022]
Abstract
The aim of this study is to investigate the pathway of diencephalic dopaminergic (DA) neuronal innervating into the spinal cord in mice, the pathway is postulated relevant to clinical restless legs syndrome (RLS). Tyrosine hydroxylase (TH) immunohistochemistry was used to identify the DA neuron. The fluorescent tracer Fluoro-Gold (FG) was stereotaxically injected into the T10-L5 spinal cord of CBL57 mice (n=20) seven days before the animals were sacrificed. The diencephalic sections were stained with TH antibody and the FG tracer present in the diencephalic DA neurons were examined under fluoresce microscope. The average number of total DA neurons per side in A11, A12, A13 and A14 was 66+/-8, 221+/-12, 350+/-17 and 254+/-21 respectively. After being injected into the spinal cord, FG reached the DA neurons within the A10 and A11 groups, but didn't target to any other DA neuron groups including the A8 and A9 groups in substantia nigra (SN). The diencephalic A11 DA neurons possessed long axons extending over several segments and possibly traversing the entire length of the spinal cord. It is the first time to report A10 and A11 DA neuron projections into the spinal cord in mice.
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Affiliation(s)
- S Qu
- Department of Neurology, Baylor College of Medicine, 6501 Fannin Street, NB205, Houston, TX 77030, USA
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41
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Abstract
OBJECTIVE To determine whether the G309D and W437OPA mutations in PINK1 gene are present in American Caucasian population of patients with Parkinson's disease (PD). METHODS We searched for the G309D and W437OPA mutation by sequencing the regions of interest in the PINK1 gene in 237 unrelated Caucasian patients. RESULTS None of the 237 samples showed the G309D or W437OPA mutations. CONCLUSIONS The G309D and W437OPA mutations in PINK1 gene probably do not represent common causes of familial or sporadic PD in a Caucasian population.
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Affiliation(s)
- H Deng
- Department of Neurology, Parkinson's Disease Center and Movement Disorders Clinic, Baylor College of Medicine, Houston, TX 77030, USA
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42
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Yang JH, Le WD, Basinger SF, Wu SM, Yang CY. Mechanisms of apoptosis in human retinal pigment epithelium induced by TNF-alpha in conditions of heavy metal ion deficiency. Invest Ophthalmol Vis Sci 2005; 46:1039-46. [PMID: 15728563 DOI: 10.1167/iovs.04-0325] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To investigate the mechanism underlying apoptosis in retinal pigment epithelium (RPE) induced by TNF-alpha in conditions of heavy metal ion deficiency. METHODS Apoptotic morphology was assessed with Hoechst 33342. FITC-VAD-fmk or antibody specific to cleaved caspase 3 was used to detect in situ activated caspases or cleaved caspase 3, respectively. JC-1 and carboxylated dichlorodihydrofluorescein diacetate were used as probes to measure mitochondrial membrane potential (Deltapsi(m)) and intracellular reactive oxygen species (rOx). RESULTS The apoptotic response of RPE cells was markedly enhanced when TNF-alpha plus actinomycin D (act-D) was coapplied with N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN), a heavy metal ion chelator. The apoptosis was caspase dependent, and a blockade with cyclosporin A (CsA), an inhibitor of the mitochondrial permeability transition (MPT), but not FK506, a calcineurin inhibitor, abolished caspase activation and subsequent apoptosis, suggesting that apoptosis requires the MPT, and that caspase activation is downstream to the MPT. MPT, observed in situ as Deltapsi(m) loss, was prevented when cells were pretreated with either CsA or the pan-caspase inhibitor z-VAD-fmk. This result suggests that apoptotic signaling is initiated by the MPT and further amplified by downstream caspases, probably through a feedback loop. An increase in rOx was observed in cells exposed to TNF-alpha+act-D+TPEN, and rOx production did not require MPT or caspase activation. In addition, application of antioxidants significantly inhibited rOx production, Deltapsi(m) loss, and apoptosis. These data suggest that the rOx may play a role as a proapoptotic signal. CONCLUSIONS The data suggest that intracellular heavy metal ions play a role in determining the apoptosis induction threshold of the inflammatory response to TNF-alpha in RPE.
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Affiliation(s)
- Jun-Hai Yang
- Department of Ophthalmology, Baylor College of Medicine, Houston, Texas, USA.
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Deng H, Le WD, Xie WJ, Pan TH, Zhang X, Jankovic J. Genetic analysis of parkin co-regulated gene (PACRG) in patients with early-onset parkinsonism. Neurosci Lett 2005; 382:297-9. [PMID: 15925106 DOI: 10.1016/j.neulet.2005.03.034] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2005] [Revised: 03/14/2005] [Accepted: 03/15/2005] [Indexed: 10/25/2022]
Abstract
Parkin co-regulated gene (PACRG) is a recently identified gene which is transcriptionally co-regulated with parkin gene (PRKN) by a shared bidirectional promoter. To determine whether early-onset parkinsonism (EOP) is associated with PACRG mutation, we screened 112 patients with EOP and found three nucleotide variants: (1) T>C transition in intron 2 (nt 87004; NT_007422), (2) C>T transition (L214L) in exon 6 (nt 585706; NT_007422), and (3) T>A substitution in intron 5 (nt 585630; NT_007422), located 18 bp upstream from exon 6. Since none of these variations appear to be pathogenically relevant, our results suggest that mutation of PACRG plays little or no role in the development of EOP.
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Affiliation(s)
- Hao Deng
- Department of Neurology, Baylor College of Medicine, 6501 Fannin Street, Houston, TX 77030, USA
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Liu X, Fan XL, Zhao Y, Luo GR, Li XP, Li R, Le WD. Estrogen provides neuroprotection against activated microglia-induced dopaminergic neuronal injury through both estrogen receptor-α and estrogen receptor-β in microglia. J Neurosci Res 2005; 81:653-65. [PMID: 16013043 DOI: 10.1002/jnr.20583] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Estrogen provides neuroprotection against neurodegenerative diseases, including Parkinson's disease. Its effects may stem from interactions with neurons, astrocytes, and microglia. We demonstrate here in primary cultures of rat mesencephalic neurons that estrogen protects them from injury induced by conditioned medium obtained from lipopolysaccharide (LPS)-activated microglia. LPS-induced nitrite production and tumor necrosis factor-alpha up-regulation in microglia were blocked by estrogen pretreatment. Estrogen neuroprotection was related to microglial activation of estrogen receptors (ERs), insofar as the protective effect of the microglia-conditioned medium was overridden by pretreatment of microglia with the ER antagonist ICI 182,780. On the other hand, the specific ERalpha antagonist, MPP dihydrochloride, only partially blocked the effects of estrogen, suggesting that estrogen protection was mediated via both ERalpha and ERbeta. LPS treatment did not change ERalpha mRNA levels in microglia, astrocytes, and neurons, but it up-regulated ERbeta mRNA levels in microglia and astrocytes. Similarly, increased ERbeta protein levels were detected in LPS-activated microglia. More interesting was that immunocytochemical analysis revealed that ERbeta was localized in the cytoplasm of microglia and in the cell nucleus of astrocytes and neurons. In summary, our results support the notion that estrogen inhibits microglial activation and thus exhibits neuroprotective effects through both ERalpha and ERbeta activation. The cytoplasm location of microglial ERbeta suggests the possible involvement of nonclassical effects of estrogen on microglia. Changes in microglial ERbeta expression levels may modulate such effects of estrogen.
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Affiliation(s)
- Xuan Liu
- Joint Laboratory of Institute of Biomedical Sciences, RuiJin Hospital, Shanghai Second Medical University, Shanghai, People's Republic of China
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45
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Abstract
Parkinson's disease (PD) is a common neurodegenerative disorder characterized by cardinal features of tremor, bradykinesia, rigidity and postural instability. In addition to the motor symptoms patients experience cognitive decline eventually resulting in severe disability. Pathologically PD is characterized by neurodegeneration in the substantia nigra pars compacta (SNc) with intracytoplasmic inclusions known as Lewy bodies. In addition to the SNc there is neurodegeneration in other areas including cerebral cortex, raphe nuclei, locus ceruleus, nucleus basalis of meynert, cranial nerves and autonomic nervous system. Recent evidence supports the role of inflammation in Parkinson's disease. Apoptosis has been shown to be one of the pathways of cell death in PD. Minocycline, a tetracycline derivative is a caspase inhibitor, and also inhibits the inducible nitric oxide synthase which are important for apoptotic cell death. Furthermore, Minocycline has been shown to block microglial activation of 6-hydroxydopamine and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-lesioned parkinsonism animal models and protect against nigrostriatal dopaminergic neurodegeneration. In this review, we present the current experimental evidence for the potential use of tetracycline derivative, minocycline, as a neuroprotective agent in PD.
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Affiliation(s)
- M Thomas
- Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA.
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Li R, Huang YG, Fang D, Le WD. (?)-Epigallocatechin gallate inhibits lipopolysaccharide-induced microglial activation and protects against inflammation-mediated dopaminergic neuronal injury. J Neurosci Res 2004; 78:723-31. [PMID: 15478178 DOI: 10.1002/jnr.20315] [Citation(s) in RCA: 146] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Microglial activation is believed to play a pivotal role in the selective neuronal injury associated with several neurodegenerative disorders, including Parkinson's disease (PD) and Alzheimer's disease. We provide evidence that (-)-epigallocatechin gallate (EGCG), a major monomer of green tea polyphenols, potently inhibits lipopolysaccharide (LPS)-activated microglial secretion of nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) through the down-regulation of inducible NO synthase and TNF-alpha expression. In addition, EGCG exerted significant protection against microglial activation-induced neuronal injury both in the human dopaminergic cell line SH-SY5Y and in primary rat mesencephalic cultures. Our study demonstrates that EGCG is a potent inhibitor of microglial activation and thus is a useful candidate for a therapeutic approach to alleviating microglia-mediated dopaminergic neuronal injury in PD.
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Affiliation(s)
- Rui Li
- Health Science Center, Shanghai Institute for Biological Science, Chinese Academy of Science, Shanghai Second Medical University, Shanghai, Peoples Republic of China
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Le WD, Xu P, Jankovic J, Jiang H, Appel SH, Smith RG, Vassilatis DK. Mutations in NR4A2 associated with familial Parkinson disease. Nat Genet 2003; 33:85-9. [PMID: 12496759 DOI: 10.1038/ng1066] [Citation(s) in RCA: 336] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2002] [Accepted: 11/05/2002] [Indexed: 12/31/2022]
Abstract
NR4A2, encoding a member of nuclear receptor superfamily, is essential for the differentiation of the nigral dopaminergic neurons. To determine whether NR4A2 is a susceptibility gene for Parkinson disease, we carried out genetic analyses in 201 individuals affected with Parkinson disease and 221 age-matched unaffected controls. We identified two mutations in NR4A2 associated with Parkinson disease (-291Tdel and -245T-->G), which map to the first exon of NR4A2 and affect one allele in 10 of 107 individuals with familial Parkinson disease but not in any individuals with sporadic Parkinson disease (n = 94) or in unaffected controls (n = 221). The age at onset of disease and clinical features of these ten individuals were not different from those of individuals with typical Parkinson disease. The mutations resulted in a marked decrease in NR4A2 mRNA levels in transfected cell lines and in lymphocytes of affected individuals. Additionally, mutations in NR4A2 affect transcription of the gene encoding tyrosine hydroxylase. These data suggest that mutations in NR4A2 can cause dopaminergic dysfunction, associated with Parkinson disease.
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Affiliation(s)
- Wei-Dong Le
- Department of Neurology, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA.
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He Y, Le WD, Appel SH. Role of Fcgamma receptors in nigral cell injury induced by Parkinson disease immunoglobulin injection into mouse substantia nigra. Exp Neurol 2002; 176:322-7. [PMID: 12359173 DOI: 10.1006/exnr.2002.7946] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Immune/inflammatory factors have been implicated in the pathogenesis of Parkinson's disease (PD). Immunoglobulin G (IgG) from patients with PD can induce injury of dopaminergic neurons following stereotaxic injection into rat substantia nigra (SN). The PD IgG can be demonstrated in vitro to activate microglia via the Fcgamma receptor (Fcgamma R) and induce dopaminergic cell injury. To confirm the involvement of microglia and their Fcgamma R in IgG-induced lesions of SN in vivo we analyzed the tyrosine hydroxylase (TH)-positive cell loss in SN par compacta (SNpc) in mice lacking Fcgamma receptors (Fcgamma R(-/-)) and wild type (Fcgamma R(+/+)). At 1 day after stereotaxic injection of PD IgG into the SN of Fcgamma R(+/+) mice there was a 27% increase in the number of CD11b-positive microglial cells and no significant loss of TH-positive cells. At 14 days after the stereotaxic injection, the number of microglial cells was increased by 42%, accompanied by a 40% loss of TH-positive neurons in the SNpc. PD IgG injection in Fcgamma R(-/-) mice resulted in no significant increase of microglia and no loss of TH-positive cells in the SNpc at any time point. The injection of F(ab')(2) fragments of PD IgG was able to induce TH-positive neuronal loss in the SNpc only when the injected animals raised antibodies against the injected human IgG fragments, which confirmed the importance of the Fcgamma R in microglial activation and nigral injury.
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Affiliation(s)
- Yi He
- Department of Neurology, Baylor College of Medicine, Houston, Texas 77030, USA
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Abstract
Dopamine receptor agonists are playing an increasingly important role in the treatment of not only patients with advanced Parkinson's disease and those with levodopa-induced motor fluctuations, but also in the early treatment of the disease. This shift has been largely due to the demonstrated levodopa-sparing effect of dopamine agonists and their putative neuroprotective effect, with evidence for the latter being based largely on experimental in vitro and in vivo studies. In this article we review the evidence for neuroprotection by the dopamine agonists pramipexole, ropinirole, pergolide, bromocriptine and apomorphine in cell cultures and animal models of injury to the substantia nigra. Most of the studies suggest that dopamine agonists may have neuroprotective effects via direct scavenging of free radicals or increasing the activities of radical-scavenging enzymes, and enhancing neurotrophic activity. However, the finding that pramipexole can normalise mitochondrial membrane potential and inhibit activity of caspase-3 in cytoplasmic hybrid cells derived from mitochondrial DNA of patients with nonfamilial Alzheimer's disease suggests an even broader implication for the neuroprotective role of dopamine agonists. Although the clinical evidence for neuroprotection by dopamine agonists is still limited, the preliminary results from several ongoing clinical trials are promising. Several longitudinal studies are currently in progress designed to demonstrate a delay or slowing of progression of Parkinson's disease using various surrogate markers of neuronal degeneration such as 18F-levodopa positron emission tomography and 123I beta-CIT (carbomethoxy-beta-4-iodophenyl-nortropane) single positron emission computed tomography. The results of these experimental and clinical studies will improve our understanding of the action of dopamine agonists and provide critical information needed for planning future therapeutic strategies for Parkinson's disease and related neurodegenerative disorders.
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Affiliation(s)
- W D Le
- Department of Neurology, Baylor College of Medicine, Houston, Texas 77030, USA.
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Le WD, Jankovic J, Xie W, Appel SH. Antioxidant property of pramipexole independent of dopamine receptor activation in neuroprotection. J Neural Transm (Vienna) 2001; 107:1165-73. [PMID: 11129106 DOI: 10.1007/s007020070030] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Pramipexole and several other dopamine agonists have been recently demonstrated to have neuroprotective effects in vitro and in vivo. We report here that pramipexole can protect DAergic cell line MES 23.5 against dopamine (DA), 6-hydroxydopamine (6-OHDA), and hydrogen peroxide (H2O2)-induced cytotoxicity in vitro possibly through antioxidant effects, and such neuroprotection could not be blocked by selective D2 or D3 antagonists. Incubation with pramipexole (5-20 microM) in MES 23.5 cell cultures increased cellular levels of glutathione (GSH), and elevated glutathione peroxidase (GSH-Px) and catalase activities, but only marginally enhanced SOD activity. Pretreatment with D2 or D3 antagonists did not block the stimulating effects of pramipexole on the cellular levels of GSH, and on the activities of GSH-Px and catalase in MES 23.5 cells. These results indicate that pramipexole's neuroprotective effects are likely associated with its antioxidant property independent of D2/D3 receptor activation.
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Affiliation(s)
- W D Le
- Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA.
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