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Blin J, Gautier C, Aubert P, Durand T, Oullier T, Aymeric L, Naveilhan P, Masson D, Neunlist M, Bach-Ngohou K. Psychological stress induces an increase in cholinergic enteric neuromuscular pathways mediated by glucocorticoid receptors. Front Neurosci 2023; 17:1100473. [PMID: 36866332 PMCID: PMC9971731 DOI: 10.3389/fnins.2023.1100473] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 01/30/2023] [Indexed: 02/16/2023] Open
Abstract
Introduction Repeated acute stress (RASt) is known to be associated with gastrointestinal dysfunctions. However, the mechanisms underlying these effects have not yet been fully understood. While glucocorticoids are clearly identified as stress hormones, their involvement in RASt-induced gut dysfunctions remains unclear, as does the function of glucocorticoid receptors (GR). The aim of our study was to evaluate the involvement of GR on RASt-induced changes in gut motility, particularly through the enteric nervous system (ENS). Methods Using a murine water avoidance stress (WAS) model, we characterized the impact of RASt upon the ENS phenotype and colonic motility. We then evaluated the expression of glucocorticoid receptors in the ENS and their functional impact upon RASt-induced changes in ENS phenotype and motor response. Results We showed that GR were expressed in myenteric neurons in the distal colon under basal conditions, and that RASt enhanced their nuclear translocation. RASt increased the proportion of ChAT-immunoreactive neurons, the tissue concentration of acetylcholine and enhanced cholinergic neuromuscular transmission as compared to controls. Finally, we showed that a GR-specific antagonist (CORT108297) prevented the increase of acetylcholine colonic tissue level and in vivo colonic motility. Discussion Our study suggests that RASt-induced functional changes in motility are, at least partly, due to a GR-dependent enhanced cholinergic component in the ENS.
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Affiliation(s)
- Justine Blin
- Nantes Université, CHU Nantes, INSERM, The Enteric Nervous System in Gut and Brain Disorders, IMAD, Nantes, France,Nantes Université, CHU Nantes, Department of Biochemistry, Nantes, France,*Correspondence: Justine Blin,
| | - Camille Gautier
- Nantes Université, CHU Nantes, INSERM, The Enteric Nervous System in Gut and Brain Disorders, IMAD, Nantes, France
| | - Philippe Aubert
- Nantes Université, CHU Nantes, INSERM, The Enteric Nervous System in Gut and Brain Disorders, IMAD, Nantes, France
| | - Tony Durand
- Nantes Université, CHU Nantes, INSERM, The Enteric Nervous System in Gut and Brain Disorders, IMAD, Nantes, France
| | - Thibauld Oullier
- Nantes Université, CHU Nantes, INSERM, The Enteric Nervous System in Gut and Brain Disorders, IMAD, Nantes, France
| | - Laetitia Aymeric
- Nantes Université, CHU Nantes, INSERM, The Enteric Nervous System in Gut and Brain Disorders, IMAD, Nantes, France,Université d’Angers, Department of Biology, Angers, France
| | - Philippe Naveilhan
- Nantes Université, CHU Nantes, INSERM, The Enteric Nervous System in Gut and Brain Disorders, IMAD, Nantes, France
| | - Damien Masson
- Nantes Université, CHU Nantes, INSERM, The Enteric Nervous System in Gut and Brain Disorders, IMAD, Nantes, France,Nantes Université, CHU Nantes, Department of Biochemistry, Nantes, France
| | - Michel Neunlist
- Nantes Université, CHU Nantes, INSERM, The Enteric Nervous System in Gut and Brain Disorders, IMAD, Nantes, France,Michel Neunlist,
| | - Kalyane Bach-Ngohou
- Nantes Université, CHU Nantes, INSERM, The Enteric Nervous System in Gut and Brain Disorders, IMAD, Nantes, France,Nantes Université, CHU Nantes, Department of Biochemistry, Nantes, France,Kalyane Bach-Ngohou,
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2
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Videlock EJ, Hatami A, Zhu C, Kawaguchi R, Chen H, Khan T, Yehya AHS, Stiles L, Joshi S, Hoffman JM, Law KM, Rankin CR, Chang L, Maidment NT, John V, Geschwind DH, Pothoulakis C. Distinct Patterns of Gene Expression Changes in the Colon and Striatum of Young Mice Overexpressing Alpha-Synuclein Support Parkinson's Disease as a Multi-System Process. JOURNAL OF PARKINSON'S DISEASE 2023; 13:1127-1147. [PMID: 37638450 PMCID: PMC10657720 DOI: 10.3233/jpd-223568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/04/2023] [Indexed: 08/29/2023]
Abstract
BACKGROUND Evidence supports a role for the gut-brain axis in Parkinson's disease (PD). Mice overexpressing human wild type α- synuclein (Thy1-haSyn) exhibit slow colonic transit prior to motor deficits, mirroring prodromal constipation in PD. Identifying molecular changes in the gut could provide both biomarkers for early diagnosis and gut-targeted therapies to prevent progression. OBJECTIVE To identify early molecular changes in the gut-brain axis in Thy1-haSyn mice through gene expression profiling. METHODS Gene expression profiling was performed on gut (colon) and brain (striatal) tissue from Thy1-haSyn and wild-type (WT) mice aged 1 and 3 months using 3' RNA sequencing. Analysis included differential expression, gene set enrichment and weighted gene co-expression network analysis (WGCNA). RESULTS At one month, differential expression (Thy1-haSyn vs. WT) of mitochondrial genes and pathways related to PD was discordant between gut and brain, with negative enrichment in brain (enriched in WT) but positive enrichment in gut. Linear regression of WGCNA modules showed partial independence of gut and brain gene expression changes. Thy1-haSyn-associated WGCNA modules in the gut were enriched for PD risk genes and PD-relevant pathways including inflammation, autophagy, and oxidative stress. Changes in gene expression were modest at 3 months. CONCLUSIONS Overexpression of haSyn acutely disrupts gene expression in the colon. While changes in colon gene expression are highly related to known PD-relevant mechanisms, they are distinct from brain changes, and in some cases, opposite in direction. These findings are in line with the emerging view of PD as a multi-system disease.
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Affiliation(s)
- Elizabeth J. Videlock
- Center for Inflammatory Bowel Diseases, Vatche and Tamar Manoukian Division of Digestive Diseases, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Asa Hatami
- The Drug Discovery Lab, Mary S. Easton Center for Alzheimer’s Disease Research, Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Chunni Zhu
- The Drug Discovery Lab, Mary S. Easton Center for Alzheimer’s Disease Research, Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Riki Kawaguchi
- The Center for Neurobehavioral Genetics, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, CA, USA
| | - Han Chen
- Center for Inflammatory Bowel Diseases, Vatche and Tamar Manoukian Division of Digestive Diseases, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Tasnin Khan
- Center for Inflammatory Bowel Diseases, Vatche and Tamar Manoukian Division of Digestive Diseases, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Ashwaq Hamid Salem Yehya
- Center for Inflammatory Bowel Diseases, Vatche and Tamar Manoukian Division of Digestive Diseases, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Linsey Stiles
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Swapna Joshi
- G. Oppenheimer Center for Neurobiology of Stress and Resilience, Vatche and Tamar Manoukian Division of Digestive Diseases, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Jill M. Hoffman
- Center for Inflammatory Bowel Diseases, Vatche and Tamar Manoukian Division of Digestive Diseases, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Ka Man Law
- Center for Inflammatory Bowel Diseases, Vatche and Tamar Manoukian Division of Digestive Diseases, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Carl Robert Rankin
- Center for Inflammatory Bowel Diseases, Vatche and Tamar Manoukian Division of Digestive Diseases, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Lin Chang
- G. Oppenheimer Center for Neurobiology of Stress and Resilience, Vatche and Tamar Manoukian Division of Digestive Diseases, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Nigel T. Maidment
- Hatos Center for Neuropharmacology, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, CA, USA
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Varghese John
- The Drug Discovery Lab, Mary S. Easton Center for Alzheimer’s Disease Research, Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Daniel H. Geschwind
- Program in Neurogenetics, Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
- Center for Autism Research and Treatment, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, CA, USA
- Institute for Precision Health, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Charalabos Pothoulakis
- Center for Inflammatory Bowel Diseases, Vatche and Tamar Manoukian Division of Digestive Diseases, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
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de Guilhem de Lataillade A, Caillaud M, Oullier T, Naveilhan P, Pellegrini C, Tolosa E, Neunlist M, Rolli-Derkinderen M, Gelpi E, Derkinderen P. LRRK2 expression in normal and pathologic human gut and in rodent enteric neural cell lines. J Neurochem 2023; 164:193-209. [PMID: 36219522 DOI: 10.1111/jnc.15704] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 09/01/2022] [Accepted: 09/15/2022] [Indexed: 02/04/2023]
Abstract
Leucine-rich repeat kinase 2 (LRRK2) gene, which is the gene most commonly associated with Parkinson's disease (PD), is also a susceptibility gene for Crohn's disease, thereby suggesting that LRRK2 may sit at the crossroads of gastrointestinal inflammation, Parkinson's, and Crohn's disease. LRRK2 protein has been studied intensely in both CNS neurons and in immune cells, but there are only few studies on LRRK2 in the enteric nervous system (ENS). LRRK2 is present in ENS ganglia and the existing studies on LRRK2 expression in colonic biopsies from PD subjects have yielded conflicting results. Herein, we propose to extend these findings by studying in more details LRRK2 expression in the ENS. LRRK2 expression was evaluated in full thickness segments of colon of 16 Lewy body, 12 non-Lewy body disorders cases, and 3 non-neurodegenerative controls and in various enteric neural cell lines. We showed that, in addition to enteric neurons, LRRK2 is constitutively expressed in enteric glial cells in both fetal and adult tissues. LRRK2 immunofluorescence intensity in the myenteric ganglia was not different between Lewy body and non-Lewy body disorders. Additionally, we identified the cAMP pathway as a key signaling pathway involved in the regulation of LRRK2 expression and phosphorylation in the enteric glial cells. Our study is the first detailed characterization of LRRK2 in the ENS and the first to show that enteric glial cells express LRRK2. Our findings provide a basis to unravel the functions of LRRK2 in the ENS and to further investigate the pathological changes in enteric synucleinopathies.
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Affiliation(s)
| | - Martial Caillaud
- Nantes Université, CHU Nantes, INSERM, The enteric nervous system in gut and brain disorders, Nantes, France
| | - Thibauld Oullier
- Nantes Université, CHU Nantes, INSERM, The enteric nervous system in gut and brain disorders, Nantes, France
| | - Philippe Naveilhan
- Nantes Université, CHU Nantes, INSERM, The enteric nervous system in gut and brain disorders, Nantes, France
| | - Carolina Pellegrini
- Unit of Histology and Embryology, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Eduardo Tolosa
- Parkinson disease and Movement Disorders Unit, Neurology Service, Hospital Clínic de Barcelona, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona (UB), Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED: CB06/05/0018-ISCIII), Barcelona, Spain
| | - Michel Neunlist
- Nantes Université, CHU Nantes, INSERM, The enteric nervous system in gut and brain disorders, Nantes, France
| | - Malvyne Rolli-Derkinderen
- Nantes Université, CHU Nantes, INSERM, The enteric nervous system in gut and brain disorders, Nantes, France
| | - Ellen Gelpi
- Neurological Tissue Bank of the Biobank-Hospital Clínic de Barcelona, Universitat de Barcelona, Barcelona, Spain.,Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Pascal Derkinderen
- Nantes Université, CHU Nantes, INSERM, The enteric nervous system in gut and brain disorders, Nantes, France
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4
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Aggregation of alpha-synuclein in enteric neurons does not impact function in vitro. Sci Rep 2022; 12:22211. [PMID: 36564445 PMCID: PMC9789045 DOI: 10.1038/s41598-022-26543-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022] Open
Abstract
Recent evidence implicates a gut-first pathogenesis in the enteric nervous system (ENS) within a portion of PD patients, yet in vitro investigations have primarily focused on the central nervous system. Here, the preformed fibril (PFF) PD model is applied with co-administered groups of butyrate and lipopolysaccharide to model the effects of the local gut microbiome. Significant PFF uptake and retention occur in isolated rat enteric neurons compared to untreated controls resulting in increasing immunostained aggregate conformation-specific, alpha-synuclein (a-Syn) average intensity between 6 µg PFF and untreated controls. Cortical neurons significantly retain PFFs with an increase in aggregated a-Syn average intensity within all dosages. Differences in growth cone morphology but not dynamics in PFF-treated ENS cultures occur. Electrophysiological recordings via a microelectrode array (MEA) indicate no overall difference in spontaneous spike rate. However, only untreated controls respond to PD-relevant dopamine stimulus, while 1 µg PFF and control populations respond to stimulus with ENS-abundant acetylcholine. Finally, no differences in substance P levels-correlated with PD and neurodegeneration-are observed. Overall, these findings suggest the ENS retains PFF dosage absent acute loss in function, however, does experience changes in growth cone morphology and dopamine-stimulated activity.
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Wang J, Yang X, Zeng W, Zhang X, Yang X, Xu Y, Liu K, Zhang Z, Xu Y, Cao X. Dual Effects: Intrastriatal Injection of α-syn N103/tau N368 Preformed Fibrils Promotes Endogenous α-synuclein Aggregates in the Proximal Colon. JOURNAL OF PARKINSON'S DISEASE 2022; 12:2097-2116. [PMID: 35912751 DOI: 10.3233/jpd-223294] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Pathological changes in the brain can affect the gastrointestinal tract, whereas there is less evidence regarding the brain-gut axis. OBJECTIVE To identify whether cerebral endogenous phosphorylated α-synuclein induces gastrointestinal dysfunction via the brain-gut axis, mediated by the vagus nerve. METHODS α-syn N103/tau N368 preformed fibrils were injected into the dorsal lateral striatum of rodents, and the cerebral and colonic synucleinopathies and changes in the enteric nervous system were analyzed. Moreover, subdiaphragmatic vagotomy was conducted to confirm the role of the vagus nerve in brain-gut propagation. RESULTS An anterograde propagation of phosphorylated α-synuclein from the brain to the proximal colon mainly via the vagus nerve was observed at one month. The accumulation of phosphorylated α-synuclein was detected in the proximal colon over time, accompanied by infiltration of macrophages and eosinophils in the mucosa and submucosa. Upon injection with lower doses of preformed fibrils, the accumulation of phosphorylated α-synuclein and dopaminergic neuron loss was reduced to levels consistent with control at six months, while the expression levels of GFAP, Iba-1, and IL-6 increased. Under high preformed fibrils dose conditions, fecal traits and gastrointestinal motility were significantly reduced at six months, and aggregations of phosphorylated α-synuclein and an increasing level of IL-1β appeared. CONCLUSION Induced endogenous α-synuclein can quickly propagate into the proximal colon mainly via the vagus nerve. Injections of low doses of preformed fibrils can elicit recovery of the enteric nervous system and degradation of α-synuclein aggregates whereas high doses cause accumulation of pathological α-synuclein, enteric inflammation, and prominent gastrointestinal dysfunction.
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Affiliation(s)
- Jialing Wang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaoman Yang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Weiqi Zeng
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaoqian Zhang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaomei Yang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yu Xu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ke Liu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhaoyuan Zhang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yan Xu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xuebing Cao
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Lassozé S, de Guilhem de Lataillade A, Oullier T, Neunslist M, Leclair-Visonneau L, Derkinderen P, Paillusson S. Comparison of commercially available antibodies for the detection of phosphorylated alpha-synuclein in primary culture of ENS. Neurogastroenterol Motil 2022; 34:e14354. [PMID: 35279896 DOI: 10.1111/nmo.14354] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 02/04/2022] [Accepted: 02/08/2022] [Indexed: 12/24/2022]
Abstract
BACKGROUND It is now well established that phosphorylated alpha-synuclein histopathology, the pathologic hallmark of Parkinson's disease (PD) is not limited to the brain but also extends to the enteric nervous system (ENS). This observation led to the hypothesis that the ENS could play a pivotal role in the development of PD. Research on the enteric synucleinopathy has, however, been hampered by difficulties in detecting phosphorylated alpha-synuclein in the ENS by Western blotting, even when the transferred membrane is fixed with an optimized protocol. This suggests that the available antibodies used in previous studies lacked of sensitivity for the detection of phosphorylated alpha-synuclein at Ser129 in enteric neurons. Here, we evaluated three recent commercially available phospho-alpha-synuclein antibodies and compared them to two antibodies used in previous research. METHODS The specificity and sensitivity of the 5 antibodies were evaluated by Western blot performed with recombinant alpha-synuclein and with protein lysates from rat primary cultures of ENS. In primary culture of ENS, additional experiments were performed with the most specific antibody in order to modulate alpha-synuclein phosphorylation and to validate its utilization in immunofluorescence experiments. RESULTS The rabbit monoclonal antibody D1R1R uniquely and robustly detected endogenous phosphorylated alpha-synuclein at Ser129 in rat primary culture of ENS without any non-specific bands, allowing for a reliable analysis of phosphorylated alpha-synuclein regulation by pharmacologic means. CONCLUSIONS AND INFERENCES Using D1R1R antibody together with the optimized protocol for membrane fixation may help deciphering the signaling pathways involved in enteric alpha-synuclein post-translational regulation in PD.
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Affiliation(s)
- Simon Lassozé
- Université de Nantes, Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France.,Department of Neurology, CHU Nantes, Nantes, France
| | - Adrien de Guilhem de Lataillade
- Université de Nantes, Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France.,Department of Neurology, CHU Nantes, Nantes, France
| | - Thibauld Oullier
- Université de Nantes, Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Michel Neunslist
- Université de Nantes, Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Laurène Leclair-Visonneau
- Université de Nantes, Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France.,Department of Neurology, CHU Nantes, Nantes, France
| | - Pascal Derkinderen
- Université de Nantes, Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France.,Department of Neurology, CHU Nantes, Nantes, France
| | - Sébastien Paillusson
- Université de Nantes, Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
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Li KL, Huang HY, Ren H, Yang XL. Role of exosomes in the pathogenesis of inflammation in Parkinson's disease. Neural Regen Res 2022; 17:1898-1906. [PMID: 35142665 PMCID: PMC8848593 DOI: 10.4103/1673-5374.335143] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Inflammatory responses, including glial cell activation and peripheral immune cell infiltration, are involved in the pathogenesis of Parkinson’s disease (PD). These inflammatory responses appear to be closely related to the release of extracellular vesicles, such as exosomes. However, the relationships among different forms of glial cell activation, synuclein dysregulation, mitochondrial dysfunction, and exosomes are complicated. This review discusses the multiple roles played by exosomes in PD-associated inflammation and concludes that exosomes can transport toxic α-synuclein oligomers to immature neurons and into the extracellular environment, inducing the oligomerization of α-synuclein in normal neurons. Misfolded α-synuclein causes microglia and astrocytes to activate and secrete exosomes. Glial cell-derived exosomes participate in communications between glial cells and neurons, triggering anti-stress and anti-inflammatory responses, in addition to axon growth. The production and release of mitochondrial vesicles and exosomes establish a new mechanism for linking mitochondrial dysfunction to systemic inflammation associated with PD. Given the relevance of exosomes as mediators of neuron-glia communication in neuroinflammation and neuropathogenesis, new targeted treatment strategies are currently being developed that use these types of extracellular vesicles as drug carriers. Exosome-mediated inflammation may be a promising target for intervention in PD patients.
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Affiliation(s)
- Ke-Lu Li
- Department of Geriatric Neurology, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan Province, China
| | - Hong-Yan Huang
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
| | - Hui Ren
- Department of Geriatric Neurology, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan Province, China
| | - Xing-Long Yang
- Department of Geriatric Neurology, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan Province, China
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Chen H, Wang K, Scheperjans F, Killinger B. Environmental triggers of Parkinson's disease - Implications of the Braak and dual-hit hypotheses. Neurobiol Dis 2022; 163:105601. [PMID: 34954321 PMCID: PMC9525101 DOI: 10.1016/j.nbd.2021.105601] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 12/05/2021] [Accepted: 12/22/2021] [Indexed: 11/22/2022] Open
Abstract
Idiopathic Parkinson's disease (PD) may take decades to develop, during which many risk or protective factors may come into play to initiate the pathogenesis or modify its progression to clinical PD. The lack of understanding of this prodromal phase of PD and the factors involved has been a major hurdle in the study of PD etiology and preventive strategies. Although still controversial, the Braak and dual-hit hypotheses that PD may start peripherally in the olfactory structures and/or the gut provides a theoretical platform to identify the triggers and modifiers of PD prodromal development and progression. This is particularly true for the search of environmental causes of PD as the olfactory structures and gut are the major human mucosal interfaces with the environment. In this review, we lay out our personal views about how the Braak and dual-hit hypotheses may help us search for the environmental triggers and modifiers for PD, summarize available experimental and epidemiological evidence, and discuss research gaps and strategies.
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Affiliation(s)
- Honglei Chen
- Epidemiology and Biostatistics, College of Human Medicine, Michigan State University, East Lansing, MI 48824, USA.
| | - Keran Wang
- Epidemiology and Biostatistics, College of Human Medicine, Michigan State University, East Lansing, MI 48824, USA
| | - Filip Scheperjans
- Department of Neurology, Helsinki University Hospital, and Clinicum, University of Helsinki, Haartmaninkatu 4, 00290 Helsinki, Finland
| | - Bryan Killinger
- Graduate College, Rush University Medical Center, Chicago, IL 60612, USA
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9
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Luo S, Zhu H, Zhang J, Wan D. The Pivotal Role of Microbiota in Modulating the Neuronal-Glial-Epithelial Unit. Infect Drug Resist 2021; 14:5613-5628. [PMID: 34992388 PMCID: PMC8711043 DOI: 10.2147/idr.s342782] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 11/26/2021] [Indexed: 12/12/2022] Open
Abstract
The enteric nervous system (ENS) consists of enteric neurons and enteric glial cells (EGCs) and controls the function of the epithelial barrier. Thus, a novel concept of neuronal-glial-epithelial unit in the gut was put forward by analogy with neuronal-glial-endothelial unit in the brain. The environment in the gastrointestinal (GI) tract is complex as it harbours millions of bacteria, which extensively attach with intestinal epithelium. The cross-talk between the neuronal-glial-endothelial unit and microbiota plays a pivotal role in modulating the epithelial barrier's permeability, intestinal development and immune response. And evidence shows dysbiosis is the potent risk factor in the pathologic process of Parkinson's disease (PD) and inflammatory bowel disease (IBD). In this review, we summarize the compelling results in favor of microbiota serving as the key modulator in the neuronal-glial-epithelial unit development and function, with profound effects on intestinal homeostasis.
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Affiliation(s)
- Siyu Luo
- Department of Emergency & Critical Care Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Huifeng Zhu
- College of Pharmaceutical Sciences & Chinese Medicine, Southwest University, Chongqing, People’s Republic of China
| | - Junhui Zhang
- Health Management Center, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Dong Wan
- Department of Emergency & Critical Care Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
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10
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Nielsen SD, Pearson NM, Seidler K. The link between the gut microbiota and Parkinson's Disease: A systematic mechanism review with focus on α-synuclein transport. Brain Res 2021; 1769:147609. [PMID: 34371014 DOI: 10.1016/j.brainres.2021.147609] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 07/29/2021] [Accepted: 08/01/2021] [Indexed: 10/20/2022]
Abstract
INTRODUCTION Research has suggested a link between the gut microbiota and Parkinson's Disease (PD), and an early involvement of gastrointestinal dysfunction has been reported in patients. A mechanism review was performed to investigate whether the neurodegenerative cascade begins in the gut; mediated by gut dysbiosis and retrograde transport of α-synuclein. This review provides a summary of microbiome composition associated with PD, and evaluates pathophysiological mechanisms from animal and in vitro models of PD. METHOD A systematic literature search was performed in PubMed; 82 of 299 papers met the inclusion criteria. RESULTS All twenty-two human case-control studies demonstrated an altered gut microbiota in PD compared to healthy controls, with results suggesting a proinflammatory phenotype present in PD. A germ-free animal study has demonstrated that gut microbiota are required for microglia activation, α-synuclein pathology and motor deficits. Accumulation of phosphorylated α-synuclein has been observed in the enteric nervous system prior to the onset of motor symptoms in animal models of PD, and there is data to support retrograde transport of α-synuclein from the gut to the brain. Different animal models of PD have demonstrated neuroinflammation, microglial activation and loss of dopaminergic neurons in the brain. CONCLUSION Evidence from this review supports the hypothesis that pathology spreads from the gut to the brain. Future animal studies using oral LPS or microbiota transplants from human PD cases could provide further insight into the entire mechanism. Prospective longitudinal microbiome studies and novel modelling approaches could help to identify functional dysbiosis and early biomarkers for PD.
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Affiliation(s)
- Sophie D Nielsen
- Centre for Nutrition Education and Lifestyle Management (CNELM), Chapel Garden, 14 Rectory Road, Wokingham, Berkshire RG40 1DH, UK.
| | - Nicola M Pearson
- Centre for Nutrition Education and Lifestyle Management (CNELM), Chapel Garden, 14 Rectory Road, Wokingham, Berkshire RG40 1DH, UK
| | - Karin Seidler
- Centre for Nutrition Education and Lifestyle Management (CNELM), Chapel Garden, 14 Rectory Road, Wokingham, Berkshire RG40 1DH, UK
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11
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das Neves SP, Delivanoglou N, Da Mesquita S. CNS-Draining Meningeal Lymphatic Vasculature: Roles, Conundrums and Future Challenges. Front Pharmacol 2021; 12:655052. [PMID: 33995074 PMCID: PMC8113819 DOI: 10.3389/fphar.2021.655052] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 04/13/2021] [Indexed: 12/11/2022] Open
Abstract
A genuine and functional lymphatic vascular system is found in the meninges that sheath the central nervous system (CNS). This unexpected (re)discovery led to a reevaluation of CNS fluid and solute drainage mechanisms, neuroimmune interactions and the involvement of meningeal lymphatics in the initiation and progression of neurological disorders. In this manuscript, we provide an overview of the development, morphology and unique functional features of meningeal lymphatics. An outline of the different factors that affect meningeal lymphatic function, such as growth factor signaling and aging, and their impact on the continuous drainage of brain-derived molecules and meningeal immune cells into the cervical lymph nodes is also provided. We also highlight the most recent discoveries about the roles of the CNS-draining lymphatic vasculature in different pathologies that have a strong neuroinflammatory component, including brain trauma, tumors, and aging-associated neurodegenerative diseases like Alzheimer's and Parkinson's. Lastly, we provide a critical appraisal of the conundrums, challenges and exciting questions involving the meningeal lymphatic system that ought to be investigated in years to come.
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Affiliation(s)
| | | | - Sandro Da Mesquita
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, United States
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12
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Schaeffer E, Kluge A, Böttner M, Zunke F, Cossais F, Berg D, Arnold P. Alpha Synuclein Connects the Gut-Brain Axis in Parkinson's Disease Patients - A View on Clinical Aspects, Cellular Pathology and Analytical Methodology. Front Cell Dev Biol 2020; 8:573696. [PMID: 33015066 PMCID: PMC7509446 DOI: 10.3389/fcell.2020.573696] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 08/18/2020] [Indexed: 12/15/2022] Open
Abstract
Parkinson’s disease (PD) is marked by different kinds of pathological features, one hallmark is the aggregation of α-synuclein (aSyn). The development of aSyn pathology in the substantia nigra is associated to the manifestation of motor deficits at the time of diagnosis. However, most of the patients suffer additionally from non-motor symptoms, which may occur already in the prodromal phase of the disease years before PD is diagnosed. Many of these symptoms manifest in the gastrointestinal system (GIT) and some data suggest a potential link to the occurrence of pathological aSyn forms within the GIT. These clinical and pathological findings lead to the idea of a gut-brain route of aSyn pathology in PD. The identification of pathological aSyn in the intestinal system, e.g., by GIT biopsies, is therefore of highest interest for early diagnosis and early intervention in the phase of formation and propagation of aSyn. However, reliable methods to discriminate between physiological and pathological forms of enteral aSyn on the cellular and biochemical level are still missing. Moreover, a better understanding of the physiological function of aSyn within the GIT as well as its structure and pathological aggregation pathways are crucial to understand its role within the enteric nervous system and its spreading from the gut to the brain. In this review, we summarize clinical manifestations of PD in the GIT, and discuss biochemical findings from enteral biopsies. The relevance of pathological aSyn forms, their connection to the gut-brain axis and new developments to identify pathologic forms of aSyn by structural features are critically reviewed.
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Affiliation(s)
- Eva Schaeffer
- Department of Neurology, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Annika Kluge
- Department of Neurology, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Martina Böttner
- Institute of Anatomy, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Friederike Zunke
- Biochemical Institute, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
| | - Francois Cossais
- Institute of Anatomy, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Daniela Berg
- Department of Neurology, Christian-Albrechts-University of Kiel, Kiel, Germany.,Department of Neurodegeneration, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Philipp Arnold
- Institute of Anatomy, Christian-Albrechts-University of Kiel, Kiel, Germany.,MSH Medical School Hamburg, Hamburg, Germany
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13
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van IJzendoorn SCD, Derkinderen P. The Intestinal Barrier in Parkinson's Disease: Current State of Knowledge. JOURNAL OF PARKINSONS DISEASE 2020; 9:S323-S329. [PMID: 31561386 PMCID: PMC6839484 DOI: 10.3233/jpd-191707] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The intestinal barrier, which primarily consists of epithelial cells stitched together with connecting proteins called tight junctions, plays a critical role in health and disease. It is in close contact with the gut microbiota on its luminal side and with the enteric neurons on the tissue side. Both microbiota and the enteric nervous system are regulatory housekeepers of the intestinal barrier. Therefore, the recently observed enteric neuropathology along with gut dysbiosis in Parkinson's disease have prompted research on intestinal permeability in this neurodegenerative disorder. In this mini-review we attempt to concisely summarize the current knowledge on intestinal barrier in Parkinson's disease. We envision future direction research that should be pursued in order to demonstrate its possible role in disease development and progression.
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Affiliation(s)
- Sven C D van IJzendoorn
- Department of Biomedical Sciences of Cells and Systems, Section Molecular Cell Biology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Pascal Derkinderen
- Inserm, U1235, Nantes, France.,University Nantes, Nantes, France.,Department of Neurology, CHU Nantes, Nantes, France
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14
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Prigent A, Chapelet G, De Guilhem de Lataillade A, Oullier T, Durieu E, Bourreille A, Duchalais E, Hardonnière K, Neunlist M, Noble W, Kerdine-Römer S, Derkinderen P, Rolli-Derkinderen M. Tau accumulates in Crohn's disease gut. FASEB J 2020; 34:9285-9296. [PMID: 32436623 DOI: 10.1096/fj.202000414r] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/09/2020] [Accepted: 04/26/2020] [Indexed: 11/11/2022]
Abstract
A sizeable body of evidence has recently emerged to suggest that gastrointestinal (GI) inflammation might be involved in the development of Parkinson's disease (PD). There is now strong epidemiological and genetical evidence linking PD to inflammatory bowel diseases and we recently demonstrated that the neuronal protein alpha-synuclein, which is critically involved in PD pathophysiology, is upregulated in inflamed segments of Crohn's colon. The microtubule associated protein tau is another neuronal protein critically involved in neurodegenerative disorders but, in contrast to alpha-synuclein, no data are available about its expression and phosphorylation patterns in inflammatory bowel diseases. Here, we examined the expression levels of tau isoforms, their phosphorylation profile and truncation in colon biopsy specimens from 16 Crohn's disease (CD) and 6 ulcerative colitis (UC) patients and compared them to samples from 16 controls. Additional experiments were performed in full thickness segments of colon of five CD and five control subjects, in primary cultures of rat enteric neurons and in nuclear factor erythroid 2-related factor (Nrf2) knockout mice. Our results show the upregulation of two main human tau isoforms in the enteric nervous system (ENS) in CD but not in UC. This upregulation was not transcriptionally regulated but instead likely resulted from a decrease in protein clearance via an Nrf2 pathway. Our findings, which provide the first detailed characterization of tau in CD, suggest that the key proteins involved in neurodegenerative disorders such as alpha-synuclein and tau, might also play a role in CD.
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Affiliation(s)
- Alice Prigent
- Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Université de Nantes, Nantes, France
| | - Guillaume Chapelet
- Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Université de Nantes, Nantes, France.,Clinical Gerontology Department, CHU Nantes, Nantes, France
| | - Adrien De Guilhem de Lataillade
- Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Université de Nantes, Nantes, France.,Department of Neurology, CHU Nantes, Nantes, France
| | - Thibauld Oullier
- Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Université de Nantes, Nantes, France
| | - Emilie Durieu
- Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Université de Nantes, Nantes, France
| | - Arnaud Bourreille
- Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Université de Nantes, Nantes, France
| | - Emilie Duchalais
- Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Université de Nantes, Nantes, France
| | - Kévin Hardonnière
- Inserm, Inflammation, Microbiome and Immunosurveillance, Université Paris-Saclay, Châtenay-Malabry, France
| | - Michel Neunlist
- Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Université de Nantes, Nantes, France
| | - Wendy Noble
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Clinical Neuroscience Institute, King's College London, London, UK
| | - Saadia Kerdine-Römer
- Inserm, Inflammation, Microbiome and Immunosurveillance, Université Paris-Saclay, Châtenay-Malabry, France
| | - Pascal Derkinderen
- Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Université de Nantes, Nantes, France.,Department of Neurology, CHU Nantes, Nantes, France
| | - Malvyne Rolli-Derkinderen
- Inserm, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Université de Nantes, Nantes, France
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15
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Trudler D, Levy‐Barazany H, Nash Y, Samuel L, Sharon R, Frenkel D. Alpha synuclein deficiency increases CD4
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T‐cells pro‐inflammatory profile in a Nurr1‐dependent manner. J Neurochem 2019; 152:61-71. [DOI: 10.1111/jnc.14871] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 09/05/2019] [Accepted: 09/10/2019] [Indexed: 01/25/2023]
Affiliation(s)
- Dorit Trudler
- Department of Neurobiology George S. Wise Faculty of Life Sciences Tel Aviv University Tel Aviv Israel
- Sagol School of Neuroscience Tel Aviv University Tel Aviv Israel
| | - Hilit Levy‐Barazany
- Department of Neurobiology George S. Wise Faculty of Life Sciences Tel Aviv University Tel Aviv Israel
| | - Yuval Nash
- Department of Neurobiology George S. Wise Faculty of Life Sciences Tel Aviv University Tel Aviv Israel
- Sagol School of Neuroscience Tel Aviv University Tel Aviv Israel
| | - Liron Samuel
- Department of Neurobiology George S. Wise Faculty of Life Sciences Tel Aviv University Tel Aviv Israel
| | - Ronit Sharon
- Faculty of Medicine Biochemistry and Molecular Biology IMRIC The Hebrew University Jerusalem Jerusalem Israel
| | - Dan Frenkel
- Department of Neurobiology George S. Wise Faculty of Life Sciences Tel Aviv University Tel Aviv Israel
- Sagol School of Neuroscience Tel Aviv University Tel Aviv Israel
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16
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Kishimoto Y, Zhu W, Hosoda W, Sen JM, Mattson MP. Chronic Mild Gut Inflammation Accelerates Brain Neuropathology and Motor Dysfunction in α-Synuclein Mutant Mice. Neuromolecular Med 2019; 21:239-249. [PMID: 31079293 PMCID: PMC6701950 DOI: 10.1007/s12017-019-08539-5] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 04/29/2019] [Indexed: 12/13/2022]
Abstract
Emerging findings suggest that Parkinson's disease (PD) pathology (α-synuclein accumulation) and neuronal dysfunction may occur first in peripheral neurons of the autonomic nervous system including the enteric branches of the vagus nerve. The risk of PD increases greatly in people over the age of 65, a period of life in which chronic inflammation is common in many organ systems including the gut. Here we report that chronic mild focal intestinal inflammation accelerates the age of disease onset in α-synuclein mutant PD mice. Wild-type and PD mice treated with 0.5% dextran sodium sulfate (DSS) in their drinking water for 12 weeks beginning at 3 months of age exhibited histological and biochemical features of mild gut inflammation. The age of onset of motor dysfunction, evaluated using a rotarod test, gait analysis, and grip strength measurements, was significantly earlier in DSS-treated PD mice compared to control PD mice. Levels of the dopaminergic neuron marker tyrosine hydroxylase in the striatum and numbers of dopaminergic neurons in the substantia nigra were reduced in PD mice with gut inflammation. Levels of total and phosphorylated α-synuclein were elevated in enteric and brain neurons in DSS-treated PD mice, suggesting that mild gut inflammation accelerates α-synuclein pathology. Markers of inflammation in the colon and brain, but not in the blood, were elevated in DSS-treated PD mice, consistent with retrograde transneuronal propagation of α-synuclein pathology and neuroinflammation from the gut to the brain. Our findings suggest that interventions that reduce gut inflammation may prove beneficial in the prevention and treatment of PD.
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Affiliation(s)
- Yuki Kishimoto
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, 21224, USA
| | - Wandi Zhu
- Immune Cells and Inflammation Section, National Institute on Aging Intramural Research Program, Baltimore, MD, 21224, USA
| | - Waki Hosoda
- Department of Pathology, The Sol Goldman Pancreatic Cancer Research Center, Johns Hopkins University School of Medicine, Baltimore, MD, 21201, USA
| | - Jyoti M Sen
- Immune Cells and Inflammation Section, National Institute on Aging Intramural Research Program, Baltimore, MD, 21224, USA.
- Immunology Program, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21105, USA.
| | - Mark P Mattson
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, 21224, USA.
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21201, USA.
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17
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Is Parkinson's disease a chronic low-grade inflammatory bowel disease? J Neurol 2019; 267:2207-2213. [PMID: 30989372 DOI: 10.1007/s00415-019-09321-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 04/09/2019] [Accepted: 04/10/2019] [Indexed: 12/17/2022]
Abstract
While the pathogenesis of Parkinson's disease is not fully understood, there is increasing evidence that inflammatory responses in the brain are implicated in both disease initiation and progression. The inflammatory process in Parkinson's disease is, however, not limited to the brain but also involves the gastrointestinal tract. High amounts of cytokines and inflammatory markers are found in the colon of Parkinson's disease patients and there is now strong epidemiological and genetical evidence linking Parkinson's disease to inflammatory bowel diseases. Recent findings obtained in both experimental inflammatory bowel diseases and Parkinson's disease further support a bidirectional link between gastrointestinal inflammation and brain neurodegeneration. Altogether, these observations suggest a role for gastrointestinal inflammation in the initiation and progression of Parkinson's disease.
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