1
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Sabbir MG. Cholinergic Receptor Muscarinic 1 Co-Localized with Mitochondria in Cultured Dorsal Root Ganglion Neurons, and Its Deletion Disrupted Mitochondrial Ultrastructure in Peripheral Neurons: Implications in Alzheimer's Disease. J Alzheimers Dis 2024; 98:247-264. [PMID: 38427478 DOI: 10.3233/jad-230883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2024]
Abstract
Background Loss of Cholinergic Receptor Muscarinic 1 (CHRM1) has been linked to the pathogenesis of Alzheimer's disease (AD). Our recent study found significantly lower CHRM1 protein levels in AD patient cortices, linked to reduced survival. Furthermore, using knockout mice (Chrm1-/-) we demonstrated that deletion of Chrm1 alters cortical mitochondrial structure and function, directly establishing a connection between its loss and mitochondrial dysfunction in the context of AD. While CHRM1's role in the brain has been extensively investigated, its impact on peripheral neurons in AD remains a crucial area of research, especially considering reported declines in peripheral nerve conduction among AD patients. Objective The objective was to characterize Chrm1 localization and mitochondrial deficits in Chrm1-/- dorsal root ganglion (DRG) neurons. Methods Recombinant proteins tagged with Green or Red Fluorescent Protein (GFP/RFP) were transiently expressed to investigate the localization of Chrm1 and mitochondria, as well as mitochondrial movement in the neurites of cultured primary mouse DRG neurons, using confocal time-lapse live cell imaging. Transmission electron microscopy was performed to examine the ultrastructure of mitochondria in both wild-type and Chrm1-/- DRGs. Results Fluorescence imaging revealed colocalization and comigration of N-terminal GFP-tagged Chrm1 and mitochondrial localization signal peptide-tagged RFP-labelled mitochondria in the DRGs neurons. A spectrum of mitochondrial structural abnormalities, including disruption and loss of cristae was observed in 87% neurons in Chrm1-/- DRGs. Conclusions This study suggests that Chrm1 may be localized in the neuronal mitochondria and loss of Chrm1 in peripheral neurons causes sever mitochondrial structural aberrations resembling AD pathology.
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Affiliation(s)
- Mohammad Golam Sabbir
- Department of Psychology and Neuroscience, Collegeof Psychology, Nova Southeastern University, Fort Lauderdale, FL, USA
- Alzo Biosciences Inc., San Diego, CA, USA
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2
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Marwaha B. Role of Tau protein in long COVID and potential therapeutic targets. Front Cell Infect Microbiol 2023; 13:1280600. [PMID: 37953801 PMCID: PMC10634420 DOI: 10.3389/fcimb.2023.1280600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Accepted: 10/06/2023] [Indexed: 11/14/2023] Open
Abstract
Introduction Long COVID is an emerging public health burden and has been defined as a syndrome with common symptoms of fatigue, shortness of breath, cognitive dysfunction, and others impacting day-to-day life, fluctuating or relapsing over, occurring for at least two months in patients with a history of probable or confirmed SARS CoV-2 infection; usually three months from the onset of illness and cannot be explained by an alternate diagnosis. The actual prevalence of long-term COVID-19 is unknown, but it is believed that more than 17 million patients in Europe may have suffered from it during pandemic. Pathophysiology Currently, there is limited understanding of the pathophysiology of this syndrome, and multiple hypotheses have been proposed. Our literature review has shown studies reporting tau deposits in tissue samples of the brain from autopsies of COVID-19 patients compared to the control group, and the in-vitro human brain organoid model has shown aberrant phosphorylation of tau protein in response to SARS-CoV-2 infection. Tauopathies, a group of neurodegenerative disorders with the salient features of tau deposits, can manifest different symptoms based on the anatomical region of brain involvement and have been shown to affect the peripheral nervous system as well and explained even in rat model studies. Long COVID has more than 203 symptoms, with predominant symptoms of fatigue, dyspnea, and cognitive dysfunction, which tauopathy-induced CNS and peripheral nervous system dysfunction can explain. There have been no studies up till now to reveal the pathophysiology of long COVID. Based on our literature review, aberrant tau phosphorylation is a promising hypothesis that can be explored in future studies. Therapeutic approaches for tauopathies have multidimensional aspects, including targeting post-translational modifications, tau aggregation, and tau clearance through the autophagy process with the help of lysosomes, which can be potential targets for developing therapeutic interventions for the long COVID. In addition, future studies can attempt to find the tau proteins in CSF and use those as biomarkers for the long COVID.
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Affiliation(s)
- Bharat Marwaha
- Department of Cardiology, Adena Health System, Chillicothe, OH, United States
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3
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Solorzano A, Brady M, Bhatt N, Johnson A, Burgess B, Leyva H, Puangmalai N, Jerez C, Wood R, Kayed R, Deane R. Central and peripheral tau retention modulated by an anti-tau antibody. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.17.553682. [PMID: 37645819 PMCID: PMC10462070 DOI: 10.1101/2023.08.17.553682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Tau protein blood levels dependent on its distribution to peripheral organs and possible elimination from the body. Thus, the peripheral distribution of CSF-derived tau protein was explored, especially since there is a transition to blood-based biomarkers and the emerging idea that tau pathology may spread beyond brain. Near infrared fluorescence (NIRF) was mainly used to analyze tau (tau-NIRF) distribution after its intracisternal or intravenous injection. There was a striking uptake of blood- or CSF-derived tau-NIRF protein by the skeletal structures, liver, small intestine (duodenum), gall bladder, kidneys, urinary bladder, lymph nodes, heart, and spleen. In aging and in older APP/PS1 mice, tau uptake in regions, such as the brain, liver, and skeleton, was increased. In bone (femur) injected tau protein was associated with integrin-binding sialoprotein (IBSP), a major non-collagenous glycoprotein that is associated with mineralization. Tau-NIRF was cleared slowly from CSF via mainly across the cribriform plate, and cervical lymph nodes. In brain, some of the CSF injected tau protein was associated with NeuN-positive and PDGFRý-positive cells, which may explain its retention. The presence of tau in the bladders suggested excretion routes of tau. CSF anti-tau antibody increased CSF tau clearance, while blood anti-tau antibody decreased tau accumulation in the femur but not in liver, kidney, and spleen. Thus, the data show a body-wide distribution and retention of CSF-derived tau protein, which increased with aging and in older APP/PS1 mice. Further work is needed to elucidate the relevance of tau accumulation in each organ to tauopathy.
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4
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Chiang JCB, Roy M, Kim J, Markoulli M, Krishnan AV. In-vivo corneal confocal microscopy: Imaging analysis, biological insights and future directions. Commun Biol 2023; 6:652. [PMID: 37336941 DOI: 10.1038/s42003-023-05005-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 05/31/2023] [Indexed: 06/21/2023] Open
Abstract
In-vivo corneal confocal microscopy is a powerful imaging technique which provides clinicians and researcher with the capabilities to observe microstructures at the ocular surfaces in significant detail. In this Mini Review, the optics and image analysis methods with the use of corneal confocal microscopy are discussed. While novel insights of neuroanatomy and biology of the eyes, particularly the ocular surface, have been provided by corneal confocal microscopy, some debatable elements observed using this technique remain and these are explored in this Mini Review. Potential improvements in imaging methodology and instrumentation are also suggested.
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Affiliation(s)
- Jeremy Chung Bo Chiang
- School of Optometry and Vision Science, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
- School of Optometry, College of Health and Life Sciences, Aston University, Birmingham, NSW, UK
| | - Maitreyee Roy
- School of Optometry and Vision Science, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
| | - Juno Kim
- School of Optometry and Vision Science, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
| | - Maria Markoulli
- School of Optometry and Vision Science, Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
| | - Arun V Krishnan
- School of Clinical Medicine, University of New South Wales, Sydney, NSW, Australia.
- Department of Neurology, Prince of Wales Hospital, Sydney, NSW, Australia.
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5
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Ferrara F, Zovi A, Masi M, Langella R, Trama U, Boccellino M, Vitiello A. Long COVID could become a widespread post-pandemic disease? A debate on the organs most affected. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2023:10.1007/s00210-023-02417-5. [PMID: 36773054 PMCID: PMC9918819 DOI: 10.1007/s00210-023-02417-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Accepted: 02/02/2023] [Indexed: 02/12/2023]
Abstract
Long COVID is an emerging problem in the current health care scenario. It is a syndrome with common symptoms of shortness of breath, fatigue, cognitive dysfunction, and other conditions that have a high impact on daily life. They are fluctuating or relapsing states that occur in patients with a history of SARS-CoV-2 infection for at least 2 months. They are usually conditions that at 3 months after onset cannot be explained by an alternative diagnosis. Currently very little is known about this syndrome. A thorough review of the literature highlights that the cause is attributable to deposits of tau protein. Massive phosphorylation of tau protein in response to SARS-CoV-2 infection occurred in brain samples from autopsies of people previously affected with COVID-19. The neurological disorders resulting from this clinical condition are termed tauopathies and can give different pathological symptoms depending on the involved anatomical region of the brain. Peripheral small-fiber neuropathies are also evident among patients with Long COVID leading to fatigue, which is the main symptom of this syndrome. Certainly more research studies could confirm the association between tau protein and Long COVID by defining the main role of tau protein as a biomarker for the diagnosis of this syndrome that is widespread in the post-pandemic period.
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Affiliation(s)
- Francesco Ferrara
- Pharmaceutical Department, Asl Napoli 3 Sud, Dell’amicizia street 22, 80035 Nola, Naples, Italy
| | - Andrea Zovi
- Ministry of Health, Viale Giorgio Ribotta 5, 00144 Rome, Italy
| | - Marta Masi
- Pharmaceutical Department, Asl Napoli 3 Sud, Dell’amicizia street 22, 80035 Nola, Naples, Italy
| | - Roberto Langella
- Italian Society of Hospital Pharmacy (SIFO), SIFO Secretariat of the Lombardy Region, Via Carlo Farini, 81, 20159 Milan, Italy
- Pharmacy Department, Agency for Health Protection (ATS) of Milan, Via Ippocrate, 45, 20161 Milan, Italy
| | - Ugo Trama
- General Direction for Health Protection and Coordination of the Campania Regional Health System, Naples, Italy
| | - Mariarosaria Boccellino
- Department of Biochemistry, Biophysics and General Pathology, University of Campania “Luigi Vanvitelli”, Naples, Italy
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6
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Shilian M, Even A, Gast H, Nguyen L, Weil M. Elongator promotes neuritogenesis via regulation of tau stability through acly activity. Front Cell Dev Biol 2022; 10:1015125. [PMID: 36393857 PMCID: PMC9644021 DOI: 10.3389/fcell.2022.1015125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 10/05/2022] [Indexed: 11/23/2022] Open
Abstract
The six subunits (Elp1 to Elp6) Elongator complex promotes specific uridine modifications in tRNA’s wobble site. Moreover, this complex has been indirectly involved in the regulation of α-tubulin acetylation in microtubules (MTs) via the stabilization of ATP-Citrate Lyase (Acly), the main cytosolic source of acetyl-CoA production in cells, a key substrate used for global protein acetylation. Here, we report additional evidence that Elongator activity is important for proper cytoskeleton remodeling as cells lacking expression of Elp1 show morphology impairment; including distinct neurite process formation and disorganization and instability of MTs. Here, we show that loss of Elongator results in a reduction of expression of the microtubule associated protein Tau (MAPT). Tau, is a well-known key MT regulator in neurons whose lysines can be competitively acetylated or ubiquitylated. Therefore, we tested whether Tau is an indirect acetylation target of Elongator. We found that a reduction of Elongator activity leads to a decrease of lysine acetylation on Tau that favors its proteasomal degradation. This phenotype was prevented by using selective deacetylase or proteasomal inhibitors. Moreover, our data demonstrate that Acly’s activity regulates the mechanism underlying Tau mediated neurite morphology defects found in Elp1 KD since both Tau levels and neurites morphology are restored due to Acly overexpression. This suggests a possible involvement of both Tau and Acly dysfunction in Familial Dysautonomia (FD), which is an autosomal recessive peripheral neuropathy caused by mutation in the ELP1 gene that severely affects Elp1 expression levels in the nervous system in FD patients in a similar way as found previously in Elp1 KD neuroblastoma cells.
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Affiliation(s)
- Michal Shilian
- Laboratory for Neurodegenerative Diseases and Personalized Medicine, The Shmunis School of Biomedicine and Cancer Research, The George S. Wise Faculty for Life Sciences, Sagol School of Neurosciences, Tel Aviv University, Tel Aviv, Israel
| | - Aviel Even
- Laboratory for Neurodegenerative Diseases and Personalized Medicine, The Shmunis School of Biomedicine and Cancer Research, The George S. Wise Faculty for Life Sciences, Sagol School of Neurosciences, Tel Aviv University, Tel Aviv, Israel
| | - Hila Gast
- Laboratory for Neurodegenerative Diseases and Personalized Medicine, The Shmunis School of Biomedicine and Cancer Research, The George S. Wise Faculty for Life Sciences, Sagol School of Neurosciences, Tel Aviv University, Tel Aviv, Israel
| | - Laurent Nguyen
- GIGA-Stem Cells and GIGA-Neurosciences, Interdisciplinary Cluster for Applied Genoproteomics (GIGAR), University of Liège, C.H.U. Sart Tilman, Belgium, BIOMED Research Institute, Hasselt, Belgium
| | - Miguel Weil
- Laboratory for Neurodegenerative Diseases and Personalized Medicine, The Shmunis School of Biomedicine and Cancer Research, The George S. Wise Faculty for Life Sciences, Sagol School of Neurosciences, Tel Aviv University, Tel Aviv, Israel
- *Correspondence: Miguel Weil,
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7
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Neuroimmune crosstalk in the cornea: The role of immune cells in corneal nerve maintenance during homeostasis and inflammation. Prog Retin Eye Res 2022; 91:101105. [PMID: 35868985 DOI: 10.1016/j.preteyeres.2022.101105] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 07/01/2022] [Accepted: 07/04/2022] [Indexed: 12/29/2022]
Abstract
In the cornea, resident immune cells are in close proximity to sensory nerves, consistent with their important roles in the maintenance of nerves in both homeostasis and inflammation. Using in vivo confocal microscopy in humans, and ex vivo immunostaining and fluorescent reporter mice to visualize corneal sensory nerves and immune cells, remarkable progress has been made to advance our understanding of the physical and functional interactions between corneal nerves and immune cells. In this review, we summarize and discuss recent studies relating to corneal immune cells and sensory nerves, and their interactions in health and disease. In particular, we consider how disrupted corneal nerve axons can induce immune cell activity, including in dendritic cells, macrophages and other infiltrating cells, directly and/or indirectly by releasing neuropeptides such as substance P and calcitonin gene-related peptide. We summarize growing evidence that the role of corneal intraepithelial immune cells is likely different in corneal wound healing versus other inflammatory-dominated conditions. The role of different types of macrophages is also discussed, including how stromal macrophages with anti-inflammatory phenotypes communicate with corneal nerves to provide neuroprotection, while macrophages with pro-inflammatory phenotypes, along with other infiltrating cells including neutrophils and CD4+ T cells, can be inhibitory to corneal re-innervation. Finally, this review considers the bidirectional interactions between corneal immune cells and corneal nerves, and how leveraging this interaction could represent a potential therapeutic approach for corneal neuropathy.
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8
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Vacchi E, Lazzarini E, Pinton S, Chiaro G, Disanto G, Marchi F, Robert T, Staedler C, Galati S, Gobbi C, Barile L, Kaelin-Lang A, Melli G. Tau protein quantification in skin biopsies differentiates tauopathies from alpha-synucleinopathies. Brain 2022; 145:2755-2768. [PMID: 35485527 DOI: 10.1093/brain/awac161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 04/03/2022] [Accepted: 04/19/2022] [Indexed: 11/12/2022] Open
Abstract
Abnormal accumulation of microtubule-associated protein tau (τ) is a characteristic feature of atypical parkinsonisms with tauopathies such as Progressive Supranuclear Palsy (PSP) and Corticobasal Degeneration (CBD). However, pathological τ has also been observed in α-synucleinopathies like Parkinson's Disease (PD) and Multiple System Atrophy (MSA). Based on the involvement of peripheral nervous system in several neurodegenerative diseases, we characterized and compared τ expression in skin biopsies of patients clinically diagnosed with PD, MSA, PSP, CBD, and in healthy control subjects. In all groups, τ protein was detected along both somatosensory and autonomic nerve fibers in the epidermis and dermis by immunofluorescence. We found by western blot the presence of mainly two different bands at 55 and 70 KDa, co-migrating with 0N4R/1N3R and 2N4R isoforms, respectively. At the RNA level, the main transcript variants were 2N and 4R, and both resulted more expressed in PSP/CBD by real-time PCR. ELISA assay demonstrated significantly higher levels of total τ protein in skin lysates of PSP/CBD compared to the other groups. Multivariate regression analysis and ROC curves analysis of τ amount at both sites showed a clinical association with tauopathies diagnosis and high diagnostic value for PSP/CBD vs. PD (sensitivity 90%, specificity 69%) and PSP/CBD vs. MSA (sensitivity 90%, specificity 86%). τ protein increase correlated with cognitive impairment in PSP/CBD. This study is a comprehensive characterization of τ in the human cutaneous peripheral nervous system in physiologic and pathologic conditions. The differential expression of τ, both at transcript and protein levels, suggests that skin biopsy, an easily accessible and minimally invasive exam, can help in discriminating among different neurodegenerative diseases.
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Affiliation(s)
- Elena Vacchi
- Laboratory for Biomedical Neurosciences, Neurocenter of Southern Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland.,Faculty of Biomedical Sciences, Università della Svizzera italiana, Lugano, Switzerland
| | - Edoardo Lazzarini
- Laboratory for Cardiovascular Theranostics, Cardiocentro Ticino Institute, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Sandra Pinton
- Laboratory for Biomedical Neurosciences, Neurocenter of Southern Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Giacomo Chiaro
- Laboratory for Biomedical Neurosciences, Neurocenter of Southern Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland.,Neurology Department, Neurocenter of Southern Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Giulio Disanto
- Neurology Department, Neurocenter of Southern Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Francesco Marchi
- Neurosurgery Department, Neurocenter of Southern Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Thomas Robert
- Faculty of Biomedical Sciences, Università della Svizzera italiana, Lugano, Switzerland.,Neurosurgery Department, Neurocenter of Southern Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Claudio Staedler
- Neurology Department, Neurocenter of Southern Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Salvatore Galati
- Faculty of Biomedical Sciences, Università della Svizzera italiana, Lugano, Switzerland.,Neurology Department, Neurocenter of Southern Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Claudio Gobbi
- Faculty of Biomedical Sciences, Università della Svizzera italiana, Lugano, Switzerland.,Neurology Department, Neurocenter of Southern Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Lucio Barile
- Faculty of Biomedical Sciences, Università della Svizzera italiana, Lugano, Switzerland.,Laboratory for Cardiovascular Theranostics, Cardiocentro Ticino Institute, Ente Ospedaliero Cantonale, Lugano, Switzerland.,Institute of Life Science, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Alain Kaelin-Lang
- Laboratory for Biomedical Neurosciences, Neurocenter of Southern Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland.,Faculty of Biomedical Sciences, Università della Svizzera italiana, Lugano, Switzerland.,Neurology Department, Neurocenter of Southern Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland.,Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Giorgia Melli
- Laboratory for Biomedical Neurosciences, Neurocenter of Southern Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland.,Faculty of Biomedical Sciences, Università della Svizzera italiana, Lugano, Switzerland.,Neurology Department, Neurocenter of Southern Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland
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9
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Jolivalt CG, Han MM, Nguyen A, Desmond F, Alves Jesus CH, Vasconselos DC, Pedneault A, Sandlin N, Dunne-Cerami S, Frizzi KE, Calcutt NA. Using Corneal Confocal Microscopy to Identify Therapeutic Agents for Diabetic Neuropathy. J Clin Med 2022; 11:jcm11092307. [PMID: 35566433 PMCID: PMC9104226 DOI: 10.3390/jcm11092307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 04/19/2022] [Accepted: 04/19/2022] [Indexed: 02/04/2023] Open
Abstract
Corneal confocal microscopy (CCM) is emerging as a tool for identifying small fiber neuropathy in both peripheral neuropathies and neurodegenerative disease of the central nervous system (CNS). The value of corneal nerves as biomarkers for efficacy of clinical interventions against small fiber neuropathy and neurodegenerative disease is less clear but may be supported by preclinical studies of investigational agents. We, therefore, used diverse investigational agents to assess concordance of efficacy against corneal nerve loss and peripheral neuropathy in a mouse model of diabetes. Ocular delivery of the peptides ciliary neurotrophic factor (CNTF) or the glucagon-like peptide (GLP) analog exendin-4, both of which prevent diabetic neuropathy when given systemically, restored corneal nerve density within 2 weeks. Similarly, ocular delivery of the muscarinic receptor antagonist cyclopentolate protected corneal nerve density while concurrently reversing indices of systemic peripheral neuropathy. Conversely, systemic delivery of the muscarinic antagonist glycopyrrolate, but not gallamine, prevented multiple indices of systemic peripheral neuropathy and concurrently protected against corneal nerve loss. These data highlight the potential for use of corneal nerve quantification by confocal microscopy as a bridging assay between in vitro and whole animal assays in drug development programs for neuroprotectants and support its use as a biomarker of efficacy against peripheral neuropathy.
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10
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Petropoulos IN, Bitirgen G, Ferdousi M, Kalteniece A, Azmi S, D'Onofrio L, Lim SH, Ponirakis G, Khan A, Gad H, Mohammed I, Mohammadi YE, Malik A, Gosal D, Kobylecki C, Silverdale M, Soran H, Alam U, Malik RA. Corneal Confocal Microscopy to Image Small Nerve Fiber Degeneration: Ophthalmology Meets Neurology. FRONTIERS IN PAIN RESEARCH 2022; 2:725363. [PMID: 35295436 PMCID: PMC8915697 DOI: 10.3389/fpain.2021.725363] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 07/26/2021] [Indexed: 12/13/2022] Open
Abstract
Neuropathic pain has multiple etiologies, but a major feature is small fiber dysfunction or damage. Corneal confocal microscopy (CCM) is a rapid non-invasive ophthalmic imaging technique that can image small nerve fibers in the cornea and has been utilized to show small nerve fiber loss in patients with diabetic and other neuropathies. CCM has comparable diagnostic utility to intraepidermal nerve fiber density for diabetic neuropathy, fibromyalgia and amyloid neuropathy and predicts the development of diabetic neuropathy. Moreover, in clinical intervention trials of patients with diabetic and sarcoid neuropathy, corneal nerve regeneration occurs early and precedes an improvement in symptoms and neurophysiology. Corneal nerve fiber loss also occurs and is associated with disease progression in multiple sclerosis, Parkinson's disease and dementia. We conclude that corneal confocal microscopy has good diagnostic and prognostic capability and fulfills the FDA criteria as a surrogate end point for clinical trials in peripheral and central neurodegenerative diseases.
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Affiliation(s)
| | - Gulfidan Bitirgen
- Department of Ophthalmology, Meram Faculty of Medicine, Necmettin Erbakan University, Konya, Turkey
| | - Maryam Ferdousi
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Alise Kalteniece
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Shazli Azmi
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom.,Centre for Diabetes, Endocrinology and Metabolism, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Luca D'Onofrio
- Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - Sze Hway Lim
- Department of Neurology, Salford Royal National Health System (NHS) Foundation Trust, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | | | - Adnan Khan
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Hoda Gad
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Ibrahim Mohammed
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar
| | | | - Ayesha Malik
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - David Gosal
- Department of Neurology, Salford Royal National Health System (NHS) Foundation Trust, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Christopher Kobylecki
- Department of Neurology, Salford Royal National Health System (NHS) Foundation Trust, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Monty Silverdale
- Department of Neurology, Salford Royal National Health System (NHS) Foundation Trust, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, United Kingdom
| | - Handrean Soran
- Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Uazman Alam
- Department of Cardiovascular and Metabolic Medicine, Clinical Sciences Centre, Pain Research Institute, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool University Hospital National Health System (NHS) Foundation Trust, Liverpool, United Kingdom
| | - Rayaz A Malik
- Department of Medicine, Weill Cornell Medicine-Qatar, Doha, Qatar.,Faculty of Biology, Medicine and Health, University of Manchester, Cardiovascular Trials Unit, Manchester University NHS Foundation Trust, Manchester, United Kingdom
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11
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Ponirakis G, Hamad HA, Khan A, Petropoulos IN, Gad H, Chandran M, Elsotouhy A, Ramadan M, Gawhale PV, Elorrabi M, Gadelseed M, Tosino R, Arasn A, Manikoth P, Abdelrahim YH, Refaee MA, Thodi N, Vattoth S, Almuhannadi H, Mahfoud ZR, Bhat H, Own A, Shuaib A, Malik RA. Loss of corneal nerves and brain volume in mild cognitive impairment and dementia. ALZHEIMER'S & DEMENTIA: TRANSLATIONAL RESEARCH & CLINICAL INTERVENTIONS 2022; 8:e12269. [PMID: 35415208 PMCID: PMC8983001 DOI: 10.1002/trc2.12269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 12/20/2021] [Accepted: 01/20/2022] [Indexed: 11/11/2022]
Abstract
Introduction This study compared the capability of corneal confocal microscopy (CCM) with magnetic resonance imaging (MRI) brain volumetry for the diagnosis of mild cognitive impairment (MCI) and dementia. Methods In this cross‐sectional study, participants with no cognitive impairment (NCI), MCI, and dementia underwent assessment of Montreal Cognitive Assessment (MoCA), MRI brain volumetry, and CCM. Results Two hundred eight participants with NCI (n = 42), MCI (n = 98), and dementia (n = 68) of comparable age and gender were studied. For MCI, the area under the curve (AUC) of CCM (76% to 81%), was higher than brain volumetry (52% to 70%). For dementia, the AUC of CCM (77% to 85%), was comparable to brain volumetry (69% to 93%). Corneal nerve fiber density, length, branch density, whole brain, hippocampus, cortical gray matter, thalamus, amygdala, and ventricle volumes were associated with cognitive impairment after adjustment for confounders (All P’s < .01). Discussion The diagnostic capability of CCM compared to brain volumetry is higher for identifying MCI and comparable for dementia, and abnormalities in both modalities are associated with cognitive impairment.
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Affiliation(s)
- Georgios Ponirakis
- Department of Medicine Weill Cornell Medicine‐Qatar Qatar Foundation Doha Qatar
| | - Hanadi Al Hamad
- Geriatric & Memory Clinic Rumailah Hospital Hamad Medical Corporation Doha Qatar
| | - Adnan Khan
- Department of Medicine Weill Cornell Medicine‐Qatar Qatar Foundation Doha Qatar
| | | | - Hoda Gad
- Department of Medicine Weill Cornell Medicine‐Qatar Qatar Foundation Doha Qatar
| | - Mani Chandran
- Geriatric & Memory Clinic Rumailah Hospital Hamad Medical Corporation Doha Qatar
| | - Ahmed Elsotouhy
- Department of Medicine Weill Cornell Medicine‐Qatar Qatar Foundation Doha Qatar
- Neuroradiology Hamad General Hospital Hamad Medical Corporation Doha Qatar
| | - Marwan Ramadan
- Geriatric & Memory Clinic Rumailah Hospital Hamad Medical Corporation Doha Qatar
| | - Priya V. Gawhale
- Geriatric & Memory Clinic Rumailah Hospital Hamad Medical Corporation Doha Qatar
| | - Marwa Elorrabi
- Geriatric & Memory Clinic Rumailah Hospital Hamad Medical Corporation Doha Qatar
| | - Masharig Gadelseed
- Geriatric & Memory Clinic Rumailah Hospital Hamad Medical Corporation Doha Qatar
| | - Rhia Tosino
- Geriatric & Memory Clinic Rumailah Hospital Hamad Medical Corporation Doha Qatar
| | - Anjum Arasn
- Geriatric & Memory Clinic Rumailah Hospital Hamad Medical Corporation Doha Qatar
| | - Pravija Manikoth
- Geriatric & Memory Clinic Rumailah Hospital Hamad Medical Corporation Doha Qatar
| | | | - Mahmoud A Refaee
- Geriatric & Memory Clinic Rumailah Hospital Hamad Medical Corporation Doha Qatar
| | - Noushad Thodi
- MRI Unit Rumailah Hospital Hamad Medical Corporation Doha Qatar
| | - Surjith Vattoth
- Radiology University of Arkansas for Medical Sciences Arkansas USA
| | - Hamad Almuhannadi
- Department of Medicine Weill Cornell Medicine‐Qatar Qatar Foundation Doha Qatar
| | - Ziyad R. Mahfoud
- Department of Medicine Weill Cornell Medicine‐Qatar Qatar Foundation Doha Qatar
| | - Harun Bhat
- Department of Medicine Weill Cornell Medicine‐Qatar Qatar Foundation Doha Qatar
| | - Ahmed Own
- Neuroradiology Hamad General Hospital Hamad Medical Corporation Doha Qatar
| | - Ashfaq Shuaib
- Department of Medicine University of Alberta Alberta Canada
| | - Rayaz A. Malik
- Department of Medicine Weill Cornell Medicine‐Qatar Qatar Foundation Doha Qatar
- Faculty of Biology Medicine and Health University of Manchester Manchester UK
- Faculty of Science and Engineering Manchester Metropolitan University Manchester UK
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12
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Li S, Shi S, Luo B, Xia F, Ha Y, Merkley KH, Motamedi M, Zhang W, Liu H. Tauopathy induces degeneration and impairs regeneration of sensory nerves in the cornea. Exp Eye Res 2021; 215:108900. [PMID: 34929160 DOI: 10.1016/j.exer.2021.108900] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 11/21/2021] [Accepted: 12/13/2021] [Indexed: 12/26/2022]
Abstract
The cornea is transparent and innervated by a dense collection of sensory nerves originating from the ocular branch of the trigeminal nerve. This study was designed to comprehensively analyze alterations of corneal sub-basal nerve plexus in a mouse model of tauopathy (P301L transgenic mice) to test the possibility of using corneal nerves as a biomarker for tauopathy. Corneal sensitivity, thickness and epithelial wound healing were measured non-invasively by aeshesiometer, optical coherence tomography and fluorescein staining, respectively. Tau, corneal nerves and immune cells were examined by immunohistochemistry or Western blot. At the early stage of tauopathy, although corneal sensitivity, thickness and nerve fiber density were not greatly altered, corneal nerve abnormalities were observed in the peripheral region of young P301L mice. With aging, the density of abnormal nerves increased, while corneal sensitivity, epithelial thickness, nerve fiber density and length decreased in middle-aged P301L mice compared with WT mice. After corneal epithelial injury in young mice, no difference in reepithelialization was observed between two groups of mice, however, the regeneration of corneal nerves in P301L mice lagged behind WT mice, which was reflected by delayed recovery of corneal sensitivity, decreased corneal nerve density and length and density of CD45+ dendriform cells in P301L mice. In conclusion, our data provide compelling evidence that corneal nerves were changed in a mouse model of tauopathy in an age-dependent manner. Moreover, tau overexpression impairs corneal nerve regeneration. These results suggest that cornea may serve as a promising ocular site for the early diagnosis of tauopathy.
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Affiliation(s)
- Shengguo Li
- Department of Ophthalmology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China; Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX, USA
| | - Shuizhen Shi
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX, USA
| | - Ban Luo
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX, USA
| | - Fan Xia
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX, USA
| | - Yonju Ha
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX, USA
| | - Kevin H Merkley
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX, USA
| | - Massoud Motamedi
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX, USA
| | - Wenbo Zhang
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX, USA; Departments of Neuroscience, Cell Biology & Anatomy, University of Texas Medical Branch, Galveston, TX, USA.
| | - Hua Liu
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX, USA.
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13
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Sah E, Krishnamurthy S, Ahmidouch MY, Gillispie GJ, Milligan C, Orr ME. The Cellular Senescence Stress Response in Post-Mitotic Brain Cells: Cell Survival at the Expense of Tissue Degeneration. Life (Basel) 2021; 11:life11030229. [PMID: 33799628 PMCID: PMC7998276 DOI: 10.3390/life11030229] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/23/2021] [Accepted: 03/02/2021] [Indexed: 01/10/2023] Open
Abstract
In 1960, Rita Levi-Montalcini and Barbara Booker made an observation that transformed neuroscience: as neurons mature, they become apoptosis resistant. The following year Leonard Hayflick and Paul Moorhead described a stable replicative arrest of cells in vitro, termed "senescence". For nearly 60 years, the cell biology fields of neuroscience and senescence ran in parallel, each separately defining phenotypes and uncovering molecular mediators to explain the 1960s observations of their founding mothers and fathers, respectively. During this time neuroscientists have consistently observed the remarkable ability of neurons to survive. Despite residing in environments of chronic inflammation and degeneration, as occurs in numerous neurodegenerative diseases, often times the neurons with highest levels of pathology resist death. Similarly, cellular senescence (hereon referred to simply as "senescence") now is recognized as a complex stress response that culminates with a change in cell fate. Instead of reacting to cellular/DNA damage by proliferation or apoptosis, senescent cells survive in a stable cell cycle arrest. Senescent cells simultaneously contribute to chronic tissue degeneration by secreting deleterious molecules that negatively impact surrounding cells. These fields have finally collided. Neuroscientists have begun applying concepts of senescence to the brain, including post-mitotic cells. This initially presented conceptual challenges to senescence cell biologists. Nonetheless, efforts to understand senescence in the context of brain aging and neurodegenerative disease and injury emerged and are advancing the field. The present review uses pre-defined criteria to evaluate evidence for post-mitotic brain cell senescence. A closer interaction between neuro and senescent cell biologists has potential to advance both disciplines and explain fundamental questions that have plagued their fields for decades.
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Affiliation(s)
- Eric Sah
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA; (E.S.); (S.K.); (M.Y.A.); (G.J.G.)
| | - Sudarshan Krishnamurthy
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA; (E.S.); (S.K.); (M.Y.A.); (G.J.G.)
- Bowman Gray Center for Medical Education, Wake Forest School of Medicine, Winston-Salem, NC 27101, USA
| | - Mohamed Y. Ahmidouch
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA; (E.S.); (S.K.); (M.Y.A.); (G.J.G.)
- Departments of Biology and Chemistry, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Gregory J. Gillispie
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA; (E.S.); (S.K.); (M.Y.A.); (G.J.G.)
- Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
| | - Carol Milligan
- Department of Neurobiology and Anatomy, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA;
| | - Miranda E. Orr
- Department of Internal Medicine, Section on Gerontology and Geriatric Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA; (E.S.); (S.K.); (M.Y.A.); (G.J.G.)
- Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
- Salisbury VA Medical Center, Salisbury, NC 28144, USA
- Correspondence:
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