1
|
Ponzini E. Tear biomarkers. Adv Clin Chem 2024; 120:69-115. [PMID: 38762243 DOI: 10.1016/bs.acc.2024.03.002] [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: 05/20/2024]
Abstract
An extensive exploration of lacrimal fluid molecular biomarkers in understanding and diagnosing a spectrum of ocular and systemic diseases is presented. The chapter provides an overview of lacrimal fluid composition, elucidating the roles of proteins, lipids, metabolites, and nucleic acids within the tear film. Pooled versus single-tear analysis is discussed to underline the benefits and challenges associated with both approaches, offering insights into optimal strategies for tear sample analysis. Subsequently, an in-depth analysis of tear collection methods is presented, with a focus on Schirmer's test strips and microcapillary tubes methods. Alternative tear collection techniques are also explored, shedding light on their applicability and advantages. Variability factors, including age, sex, and diurnal fluctuations, are examined in the context of their impact on tear biomarker analysis. The main body of the chapter is dedicated to discussing specific biomarkers associated with ocular discomfort and a wide array of ocular diseases. From dry eye disease and thyroid-associated ophthalmopathy to keratoconus, age-related macular degeneration, diabetic retinopathy, and glaucoma, the intricate relationship between molecular biomarkers and these conditions is thoroughly dissected. Expanding beyond ocular pathologies, the chapter explores the applicability of tear biomarkers in diagnosing systemic diseases such as multiple sclerosis, amyotrophic lateral sclerosis, Alzheimer's disease, Parkinson's disease, and cancer. This broader perspective underscores the potential of lacrimal fluid analysis in offering non-invasive diagnostic tools for conditions with far-reaching implications.
Collapse
Affiliation(s)
- Erika Ponzini
- Department of Materials Science, University of Milano Bicocca, Milan, Italy; COMiB Research Center, University of Milano Bicocca, Milan, Italy.
| |
Collapse
|
2
|
Luib E, Demleitner AF, Cordts I, Westenberg E, Rau P, Pürner D, Haller B, Lingor P. Reduced tear fluid production in neurological diseases: a cohort study in 708 patients. J Neurol 2024; 271:1824-1836. [PMID: 38063868 PMCID: PMC10973005 DOI: 10.1007/s00415-023-12104-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 10/27/2023] [Accepted: 10/28/2023] [Indexed: 03/28/2024]
Abstract
BACKGROUND Tear fluid (TF) production is an important component of normal ocular function. It is regulated by parasympathetic and sympathetic innervation. Because parasympathetic nerve fibers originate in the brainstem, pathology in this brain region may affect TF production. For example, a reduction in TF production has been described in patients with Parkinson's disease (PD). METHODS TF was collected at one center from 772 individuals, 708 of which were patients with different neurological diseases, and 64 healthy controls. Wetting lengths (WL) were recorded using Schirmer test strips with a collection time of 10 min. RESULTS WL correlated negatively with age and was significantly reduced in subgroups of patients with neurodegenerative diseases (NDDs) (PD, Amyotrophic lateral sclerosis (ALS), other motor neuron diseases (MNDs)), as well as inflammatory/autoimmune/infectious central nervous system (CNS) diseases and vascular CNS diseases (VCDs), even if corrected for age or sex. While temperature had a significant negative effect on TF production, other environmental factors, such as hours of sunlight and humidity, did not. CONCLUSION WL was altered in many neurological diseases compared to healthy controls. Most importantly, we observed a reduction of WL in NDDs, independent of age or sex. This study highlights the potential of WL as an easily obtainable parameter and suggests functional alterations in the autonomic innervation in various neurological disorders.
Collapse
Affiliation(s)
- Elena Luib
- Department of Neurology, Klinikum rechts der Isar, School of Medicine, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany
| | - Antonia F Demleitner
- Department of Neurology, Klinikum rechts der Isar, School of Medicine, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany
| | - Isabell Cordts
- Department of Neurology, Klinikum rechts der Isar, School of Medicine, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany
| | - Erica Westenberg
- Department of Neurology, Klinikum rechts der Isar, School of Medicine, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany
| | - Petra Rau
- Department of Neurology, Klinikum rechts der Isar, School of Medicine, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany
| | - Dominik Pürner
- Department of Neurology, Klinikum rechts der Isar, School of Medicine, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany
| | - Bernhard Haller
- Institute of AI and Informatics in Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Paul Lingor
- Department of Neurology, Klinikum rechts der Isar, School of Medicine, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany.
- DZNE, German Center for Neurodegenerative Diseases, Munich, Germany.
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
| |
Collapse
|
3
|
Tan Y, De La Toba E, Rubakhin SS, Labriola LT, Canfield C, Pan D, Sweedler JV. NanoLC-timsTOF-Assisted Analysis of Glycated Albumin in Diabetes-Affected Plasma and Tears. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:106-113. [PMID: 38016044 PMCID: PMC10843563 DOI: 10.1021/jasms.3c00331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2023]
Abstract
Glycation is a spontaneous and nonenzymatic glycosylation. Glycated albumin (GA), which serves as an important biomarker in plasma in the diagnosis and characterization of diabetes, can be passively filtered from the plasma to tears. Tears are important targets for research in clinical diagnostics due to the ability to collect this biofluid noninvasively and repeatably. Therefore, the analysis of GA in tear film provides information for monitoring diabetes progression independent of blood pathologies. Due to the limited volume (1-5 μL) of natural tear film, we developed a small volume assay using a nano liquid chromatography-trapped ion mobility spectrometry-time-of-flight MS (nanoLC-timsTOF) platform for the analysis of glycated albumin in human plasma and tear films affected by diabetes. The peptides containing lysine 525, which is the main glycation site in GA, were relatively quantified and represented as the GA level. The results of the measurements showed that GA levels were significantly higher in diabetes-affected plasma and tears compared to controls with a p-value < 0.01. A strong correlation of glycated albumin levels was observed for the plasma and tear film in diabetes samples (Pearson coefficient 0.92 with a p-value 0.0012). Moreover, the number of GA glycation sites was significantly higher in diabetes-affected plasma and tear comparatively to controls. Among all the glycation sites in plasma albumin, the GA level quantified by lysine 136/137 had a strong correlation with more commonly used lysine 525, suggesting that lysine 136 /137 is an alternative diabetes biomarker in plasma. Overall, our findings demonstrate GA in tears as a biomarker for monitoring diabetes progression, highlighting new possibilities for quick and noninvasive diabetes detection and monitoring.
Collapse
Affiliation(s)
- Yanqi Tan
- Department of Chemistry and the Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Eduardo De La Toba
- Department of Chemistry and the Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Stanislav S Rubakhin
- Department of Chemistry and the Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | | | | | - Dipanjan Pan
- Department of Nuclear Engineering and Materials Science and Engineering, Pennsylvania State University, State College, Pennsylvania 16802, United States
| | - Jonathan V Sweedler
- Department of Chemistry and the Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| |
Collapse
|
4
|
Camacho-Ordonez A, Cervantes-Arriaga A, Rodríguez-Violante M, Hernandez-Medrano AJ, Somilleda-Ventura SA, Pérez-Cano HJ, Nava-Castañeda Á, Guerrero-Berger O. Is there any correlation between alpha-synuclein levels in tears and retinal layer thickness in Parkinson's disease? Eur J Ophthalmol 2024; 34:252-259. [PMID: 37151018 DOI: 10.1177/11206721231173725] [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: 05/09/2023]
Abstract
PURPOSE To determine the total alpha-synuclein (αSyn) reflex tears and its association with retinal layers thickness in Parkinson's disease (PD). METHODS Fifty-two eyes of 26 PD subjects and 52 eyes of age-and sex-matched healthy controls were included. Total αSyn in reflex tears was quantified using a human total αSyn enzyme-linked immunosorbent assay (ELISA) kit. The retinal thickness was evaluated with spectral-domain optical coherence tomography. The Movement Disorder Society-Unified Parkinsońs Disease Rating Scale (MDS-UPDRS), Non-Motor Symptoms Scale (NMSS), and Montreal Cognitive Assessment (MoCA) were used to assess motor, non-motor, and cognition. RESULTS In PD, total αSyn levels were increased compared to control subjects [1.76pg/mL (IQR 1.74-1.80) vs 1.73pg/mL (IQR 1.70-1.77), p < 0.004]. The nerve fiber layer, ganglion cell layer, internal plexiform layer, inner nuclear layer, and outer nuclear layer were thinner in PD in comparison with controls (p < 0.05). The outer plexiform layer and retinal pigment epithelium were thicker in PD (p < 0.05). The total αSyn levels positively correlated with the central volume of the inner nuclear layer (r = 0.357, p = 0.009). CONCLUSION Total αSyn reflex tear levels were increased in subjects with PD compared to controls. PD patients showed significant thinning of the inner retinal layers and thickening of outer retinal layers in comparison with controls. Total αSyn levels positively correlate with the central volume of the inner nuclear layer in PD. The combination of these biomarkers might have a possible role as a diagnostic tool in PD subjects.
Collapse
Affiliation(s)
- Azyadeh Camacho-Ordonez
- Neuro-ophthalmology Clinic, National Institute of Neurology and Neurosurgery, Mexico City, Mexico
- Anterior Segment Department, Fundacion Hospital Nuestra Señora de la Luz, IAP, Mexico City, Mexico
| | - Amin Cervantes-Arriaga
- Movement Disorder Clinic, National Institute of Neurology and Neurosurgery, Mexico City, Mexico
| | | | | | | | - Hector J Pérez-Cano
- Biomedical Research Center, Fundacion Hospital Nuestra Señora de la Luz, IAP, Mexico City, Mexico
| | - Ángel Nava-Castañeda
- Oculoplastics Department, Instituto de Oftalmologia Fundacion Conde de Valenciana IAP, Mexico City, Mexico
| | - Oscar Guerrero-Berger
- Anterior Segment Department, Fundacion Hospital Nuestra Señora de la Luz, IAP, Mexico City, Mexico
| |
Collapse
|
5
|
Vijiaratnam N, Foltynie T. How should we be using biomarkers in trials of disease modification in Parkinson's disease? Brain 2023; 146:4845-4869. [PMID: 37536279 PMCID: PMC10690028 DOI: 10.1093/brain/awad265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 07/18/2023] [Accepted: 07/22/2023] [Indexed: 08/05/2023] Open
Abstract
The recent validation of the α-synuclein seed amplification assay as a biomarker with high sensitivity and specificity for the diagnosis of Parkinson's disease has formed the backbone for a proposed staging system for incorporation in Parkinson's disease clinical studies and trials. The routine use of this biomarker should greatly aid in the accuracy of diagnosis during recruitment of Parkinson's disease patients into trials (as distinct from patients with non-Parkinson's disease parkinsonism or non-Parkinson's disease tremors). There remain, however, further challenges in the pursuit of biomarkers for clinical trials of disease modifying agents in Parkinson's disease, namely: optimizing the distinction between different α-synucleinopathies; the selection of subgroups most likely to benefit from a candidate disease modifying agent; a sensitive means of confirming target engagement; and the early prediction of longer-term clinical benefit. For example, levels of CSF proteins such as the lysosomal enzyme β-glucocerebrosidase may assist in prognostication or allow enrichment of appropriate patients into disease modifying trials of agents with this enzyme as the target; the presence of coexisting Alzheimer's disease-like pathology (detectable through CSF levels of amyloid-β42 and tau) can predict subsequent cognitive decline; imaging techniques such as free-water or neuromelanin MRI may objectively track decline in Parkinson's disease even in its later stages. The exploitation of additional biomarkers to the α-synuclein seed amplification assay will, therefore, greatly add to our ability to plan trials and assess the disease modifying properties of interventions. The choice of which biomarker(s) to use in the context of disease modifying clinical trials will depend on the intervention, the stage (at risk, premotor, motor, complex) of the population recruited and the aims of the trial. The progress already made lends hope that panels of fluid biomarkers in tandem with structural or functional imaging may provide sensitive and objective methods of confirming that an intervention is modifying a key pathophysiological process of Parkinson's disease. However, correlation with clinical progression does not necessarily equate to causation, and the ongoing validation of quantitative biomarkers will depend on insightful clinical-genetic-pathophysiological comparisons incorporating longitudinal biomarker changes from those at genetic risk with evidence of onset of the pathophysiology and those at each stage of manifest clinical Parkinson's disease.
Collapse
Affiliation(s)
- Nirosen Vijiaratnam
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Thomas Foltynie
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| |
Collapse
|
6
|
Seo H, Chung WG, Kwon YW, Kim S, Hong YM, Park W, Kim E, Lee J, Lee S, Kim M, Lim K, Jeong I, Song H, Park JU. Smart Contact Lenses as Wearable Ophthalmic Devices for Disease Monitoring and Health Management. Chem Rev 2023; 123:11488-11558. [PMID: 37748126 PMCID: PMC10571045 DOI: 10.1021/acs.chemrev.3c00290] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Indexed: 09/27/2023]
Abstract
The eye contains a complex network of physiological information and biomarkers for monitoring disease and managing health, and ocular devices can be used to effectively perform point-of-care diagnosis and disease management. This comprehensive review describes the target biomarkers and various diseases, including ophthalmic diseases, metabolic diseases, and neurological diseases, based on the physiological and anatomical background of the eye. This review also includes the recent technologies utilized in eye-wearable medical devices and the latest trends in wearable ophthalmic devices, specifically smart contact lenses for the purpose of disease management. After introducing other ocular devices such as the retinal prosthesis, we further discuss the current challenges and potential possibilities of smart contact lenses.
Collapse
Affiliation(s)
- Hunkyu Seo
- Department
of Materials Science and Engineering, Yonsei
University, Seoul 03722, Republic
of Korea
| | - Won Gi Chung
- Department
of Materials Science and Engineering, Yonsei
University, Seoul 03722, Republic
of Korea
| | - Yong Won Kwon
- Department
of Materials Science and Engineering, Yonsei
University, Seoul 03722, Republic
of Korea
| | - Sumin Kim
- Department
of Materials Science and Engineering, Yonsei
University, Seoul 03722, Republic
of Korea
| | - Yeon-Mi Hong
- Department
of Materials Science and Engineering, Yonsei
University, Seoul 03722, Republic
of Korea
| | - Wonjung Park
- Department
of Materials Science and Engineering, Yonsei
University, Seoul 03722, Republic
of Korea
| | - Enji Kim
- Department
of Materials Science and Engineering, Yonsei
University, Seoul 03722, Republic
of Korea
| | - Jakyoung Lee
- Department
of Materials Science and Engineering, Yonsei
University, Seoul 03722, Republic
of Korea
| | - Sanghoon Lee
- Department
of Materials Science and Engineering, Yonsei
University, Seoul 03722, Republic
of Korea
| | - Moohyun Kim
- Department
of Materials Science and Engineering, Yonsei
University, Seoul 03722, Republic
of Korea
| | - Kyeonghee Lim
- Department
of Materials Science and Engineering, Yonsei
University, Seoul 03722, Republic
of Korea
| | - Inhea Jeong
- Department
of Materials Science and Engineering, Yonsei
University, Seoul 03722, Republic
of Korea
| | - Hayoung Song
- Department
of Materials Science and Engineering, Yonsei
University, Seoul 03722, Republic
of Korea
| | - Jang-Ung Park
- Department
of Materials Science and Engineering, Yonsei
University, Seoul 03722, Republic
of Korea
- Department
of Neurosurgery, Yonsei University College
of Medicine, Seoul 03722, Republic of Korea
- Center
for Nanomedicine, Institute for Basic Science (IBS), Yonsei University, Seoul 03722, Republic
of Korea
| |
Collapse
|
7
|
Guntermann A, Fatoba O, Kronenberg M, Reinehr S, Grotegut P, Schargus M, Tsai T, Ivanova S, Serschnitzki B, Kumowski N, Maier C, Marcus K, Dick HB, Joachim SC, May C. Investigation of Inter- and Intra-Day Variability of Tear Fluid Regarding Flow Rate, Protein Concentration as well as Protein Composition. Invest Ophthalmol Vis Sci 2023; 64:13. [PMID: 37815507 PMCID: PMC10573576 DOI: 10.1167/iovs.64.13.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 07/21/2023] [Indexed: 10/11/2023] Open
Abstract
Purpose The purpose of this study was to present the determination of inter- and intra-day variations in tear flow rate, and tear fluid protein concentration, as well as protein composition regarding their impact for future biomarker studies. Methods Tear fluid was collected noninvasively from 18 healthy subjects by performing Schirmer tests at 4 different time points repetitive in a period of 2 days. The tear flow rate on the Schirmer test strips was measured. Proteins were extracted from strips and quantified using amino acid analysis. Protein composition was analyzed by the strips data-independent (DIA) based mass spectrometry. To exclude any impairments to health, volunteers underwent a detailed neurological as well as an ophthalmological examination. Results Whether tear fluid was collected from oculus sinister or oculus dexter did not affect the tear flow rate (P ≈ 0.63) or protein concentration (P ≈ 0.97) of individual subjects. Moreover, protein concentration was independent from the tear volume, so that a change in volume may only influence the total protein amount. When the examination days were compared, investigation of tear flow rate (P ≈ 0.001) and protein concentration (P ≈ 0.0003) indicated significant differences. Further, mass spectrometric analysis of tear fluid revealed 11 differentially regulated proteins when comparing both examination days. Conclusions Our findings provide evidence of inter-day variation in tear flow rate, tear proteome concentration, and composition in healthy subjects, suggesting that inter-day variation needs to be taken into consideration in biomarker research of tear fluid. Identified proteins were assigned to functions in the immune response, oxidative and reducing processes, as well as mannose metabolism.
Collapse
Affiliation(s)
- Annika Guntermann
- Ruhr-University Bochum, Center for Protein Diagnostics (ProDi), Medical Proteome Analysis, Bochum, Germany
- Ruhr-University Bochum, Medical Faculty, Medizinisches Proteom-Center, Bochum, Germany
| | - Oluwaseun Fatoba
- Ruhr-University Bochum, Center for Protein Diagnostics (ProDi), Medical Proteome Analysis, Bochum, Germany
- Ruhr-University Bochum, Medical Faculty, Medizinisches Proteom-Center, Bochum, Germany
| | - Marc Kronenberg
- Ruhr-University Bochum, Center for Protein Diagnostics (ProDi), Medical Proteome Analysis, Bochum, Germany
- Ruhr-University Bochum, Medical Faculty, Medizinisches Proteom-Center, Bochum, Germany
| | - Sabrina Reinehr
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Pia Grotegut
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Marc Schargus
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
- Department of Ophthalmology, University Hospital Duesseldorf, Heinrich-Heine-University Duesseldorf, Duesseldorf, Germany
- Asklepios Eye Hospital Nord-Heidberg, Hamburg, Germany
| | - Teresa Tsai
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Svetlana Ivanova
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Bettina Serschnitzki
- Ruhr-University Bochum, Center for Protein Diagnostics (ProDi), Medical Proteome Analysis, Bochum, Germany
- Ruhr-University Bochum, Medical Faculty, Medizinisches Proteom-Center, Bochum, Germany
| | - Nina Kumowski
- Department of Pain Medicine, BG University Hospital Bergmannsheil GmbH, Ruhr-University Bochum, Bochum, Germany
- Medical Clinic I - Cardiology, Angiology and Internal Intensive Care Medicine, RWTH Aachen University Hospital, Aachen, Germany
| | - Christoph Maier
- University Children's Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Katrin Marcus
- Ruhr-University Bochum, Center for Protein Diagnostics (ProDi), Medical Proteome Analysis, Bochum, Germany
- Ruhr-University Bochum, Medical Faculty, Medizinisches Proteom-Center, Bochum, Germany
| | - H Burkhard Dick
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Stephanie C Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Caroline May
- Ruhr-University Bochum, Center for Protein Diagnostics (ProDi), Medical Proteome Analysis, Bochum, Germany
- Ruhr-University Bochum, Medical Faculty, Medizinisches Proteom-Center, Bochum, Germany
| |
Collapse
|
8
|
Brembati V, Faustini G, Longhena F, Bellucci A. Alpha synuclein post translational modifications: potential targets for Parkinson's disease therapy? Front Mol Neurosci 2023; 16:1197853. [PMID: 37305556 PMCID: PMC10248004 DOI: 10.3389/fnmol.2023.1197853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 04/27/2023] [Indexed: 06/13/2023] Open
Abstract
Parkinson's disease (PD) is the most common neurodegenerative disorder with motor symptoms. The neuropathological alterations characterizing the brain of patients with PD include the loss of dopaminergic neurons of the nigrostriatal system and the presence of Lewy bodies (LB), intraneuronal inclusions that are mainly composed of alpha-synuclein (α-Syn) fibrils. The accumulation of α-Syn in insoluble aggregates is a main neuropathological feature in PD and in other neurodegenerative diseases, including LB dementia (LBD) and multiple system atrophy (MSA), which are therefore defined as synucleinopathies. Compelling evidence supports that α-Syn post translational modifications (PTMs) such as phosphorylation, nitration, acetylation, O-GlcNAcylation, glycation, SUMOylation, ubiquitination and C-terminal cleavage, play important roles in the modulation α-Syn aggregation, solubility, turnover and membrane binding. In particular, PTMs can impact on α-Syn conformational state, thus supporting that their modulation can in turn affect α-Syn aggregation and its ability to seed further soluble α-Syn fibrillation. This review focuses on the importance of α-Syn PTMs in PD pathophysiology but also aims at highlighting their general relevance as possible biomarkers and, more importantly, as innovative therapeutic targets for synucleinopathies. In addition, we call attention to the multiple challenges that we still need to face to enable the development of novel therapeutic approaches modulating α-Syn PTMs.
Collapse
|
9
|
Khan MA, Haider N, Singh T, Bandopadhyay R, Ghoneim MM, Alshehri S, Taha M, Ahmad J, Mishra A. Promising biomarkers and therapeutic targets for the management of Parkinson's disease: recent advancements and contemporary research. Metab Brain Dis 2023; 38:873-919. [PMID: 36807081 DOI: 10.1007/s11011-023-01180-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 02/04/2023] [Indexed: 02/23/2023]
Abstract
Parkinson's disease (PD) is one of the progressive neurological diseases which affect around 10 million population worldwide. The clinical manifestation of motor symptoms in PD patients appears later when most dopaminergic neurons have degenerated. Thus, for better management of PD, the development of accurate biomarkers for the early prognosis of PD is imperative. The present work will discuss the potential biomarkers from various attributes covering biochemical, microRNA, and neuroimaging aspects (α-synuclein, DJ-1, UCH-L1, β-glucocerebrosidase, BDNF, etc.) for diagnosis, recent development in PD management, and major limitations with current and conventional anti-Parkinson therapy. This manuscript summarizes potential biomarkers and therapeutic targets, based on available preclinical and clinical evidence, for better management of PD.
Collapse
Affiliation(s)
- Mohammad Ahmed Khan
- Department of Pharmacology, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, 110062, India
| | - Nafis Haider
- Prince Sultan Military College of Health Sciences, Dhahran, 34313, Saudi Arabia
| | - Tanveer Singh
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX, 77807, USA
| | - Ritam Bandopadhyay
- Department of Pharmacology, School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, 144411, Punjab, India
| | - Mohammed M Ghoneim
- Department of Pharmacy Practice, College of Pharmacy, AlMaarefa University, Ad Diriyah, 13713, Saudi Arabia
| | - Sultan Alshehri
- Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Murtada Taha
- Prince Sultan Military College of Health Sciences, Dhahran, 34313, Saudi Arabia
| | - Javed Ahmad
- Department of Pharmaceutics, College of Pharmacy, Najran University, Najran, 11001, Saudi Arabia
| | - Awanish Mishra
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER) - Guwahati, Sila Katamur (Halugurisuk), Kamrup, Changsari, Assam, 781101, India.
| |
Collapse
|
10
|
Gijs M, Arumugam S, van de Sande N, Webers CAB, Sethu S, Ghosh A, Shetty R, Vehof J, Nuijts RMMA. Pre-analytical sample handling effects on tear fluid protein levels. Sci Rep 2023; 13:1317. [PMID: 36693949 PMCID: PMC9873914 DOI: 10.1038/s41598-023-28363-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 01/16/2023] [Indexed: 01/25/2023] Open
Abstract
Tear fluid is emerging as a source of non-invasive biomarkers, both for ocular and systemic conditions. Accurate quantification of tear proteins can be improved by standardizing methods to collect and process tear fluid. The aim of this study was to determine sample handling factors that may influence the tear protein biomarker profile. Tear fluid was collected using Schirmer's strips. Tear proteins were extracted by elution through centrifugation. Total protein content was determined using the bicinchoninic acid assay. Key concepts that apply to the entire sample processing cycle are tear sampling, tear storage, protein extraction and data normalization. Differences in wetting or migration length were observed between Schirmer's strips from different manufacturers, and between protein-free and protein-rich solutions. One unit of migration length (mm) did not correspond to one unit of volume (µL). A positive correlation (r = 0.6671, p < 0.0001) was observed between migration length and total tear protein content. The most beneficial storage conditions were strips that were not stored (+ 21.8%), or underwent 'wet' storage (+ 11.1%). Protein recovery was the highest in 400 µL extraction buffer and independent of protein molecular weight. This study helps to explain inter- and intra-variability that is often seen with tear biomarker research. This information is critical to ensure accuracy of test results, as tear biomarkers will be used for patient management and in clinical trials in the near future. This study also highlights the need for standardization of Schirmer's strip manufacturing, tear fluid processing and analyte concentration normalization.
Collapse
Affiliation(s)
- Marlies Gijs
- University Eye Clinic Maastricht, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center (MUMC+), P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands.
| | - Sinthuja Arumugam
- University Eye Clinic Maastricht, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center (MUMC+), P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands
| | - Nienke van de Sande
- University Eye Clinic Maastricht, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center (MUMC+), P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands
| | - Carroll A B Webers
- University Eye Clinic Maastricht, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center (MUMC+), P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands
| | - Swaminathan Sethu
- GROW Research Laboratory, Narayana Nethralaya Foundation, Bangalore, India
| | - Arkasubhra Ghosh
- GROW Research Laboratory, Narayana Nethralaya Foundation, Bangalore, India
| | - Rohit Shetty
- University Eye Clinic Maastricht, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center (MUMC+), P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands.,GROW Research Laboratory, Narayana Nethralaya Foundation, Bangalore, India.,Department of Cornea and Refractive Surgery, Narayana Nethralaya, Bangalore, India
| | - Jelle Vehof
- Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.,Dutch Dry Eye Clinic, Velp, The Netherlands.,Department of Ophthalmology, Vestfold Hospital Trust, Tønsberg, Norway
| | - Rudy M M A Nuijts
- University Eye Clinic Maastricht, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center (MUMC+), P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands.,Department of Ophthalmology, Zuyderland Medical Center, Heerlen, The Netherlands
| |
Collapse
|
11
|
Current Diagnostic Methods and Non-Coding RNAs as Possible Biomarkers in Huntington’s Disease. Genes (Basel) 2022; 13:genes13112017. [PMID: 36360254 PMCID: PMC9689996 DOI: 10.3390/genes13112017] [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: 08/28/2022] [Revised: 10/20/2022] [Accepted: 10/24/2022] [Indexed: 11/06/2022] Open
Abstract
Whether as a cause or a symptom, RNA transcription is recurrently altered in pathologic conditions. This is also true for non-coding RNAs, with regulatory functions in a variety of processes such as differentiation, cell identity and metabolism. In line with their increasingly recognized roles in cellular pathways, RNAs are also currently evaluated as possible disease biomarkers. They could be informative not only to follow disease progression and assess treatment efficacy in clinics, but also to aid in the development of new therapeutic approaches. This is especially important for neurological and genetic disorders, where the administration of appropriate treatment during the disease prodromal stage could significantly delay, if not halt, disease progression. In this review we focus on the current status of biomarkers in Huntington’s Disease (HD), a fatal hereditary and degenerative disease condition. First, we revise the sources and type of wet biomarkers currently in use. Then, we explore the feasibility of different RNA types (miRNA, ncRNA, circRNA) as possible biomarker candidates, discussing potential advantages, disadvantages, sources of origin and the ongoing investigations on this topic.
Collapse
|
12
|
Król-Grzymała A, Sienkiewicz-Szłapka E, Fiedorowicz E, Rozmus D, Cieślińska A, Grzybowski A. Tear Biomarkers in Alzheimer's and Parkinson's Diseases, and Multiple Sclerosis: Implications for Diagnosis (Systematic Review). Int J Mol Sci 2022; 23:10123. [PMID: 36077520 PMCID: PMC9456033 DOI: 10.3390/ijms231710123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/19/2022] [Accepted: 08/29/2022] [Indexed: 11/16/2022] Open
Abstract
Biological material is one of the most important aspects that allow for the correct diagnosis of the disease, and tears are an interesting subject of research because of the simplicity of collection, as the well as the relation to the components similar to other body fluids. In this review, biomarkers for Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS) in tears are investigated and analyzed. Records were obtained from the PubMed and Google Scholar databases in a timeline of 2015-2022. The keywords were: tear film/tear biochemistry/tear biomarkers + diseases (AD, PD, or MS). The recent original studies were analyzed, discussed, and biomarkers present in tears that can be used for the diagnosis and management of AD, PD, and MS diseases were shown. α-synTotal and α-synOligo, lactoferrin, norepinephrine, adrenaline, epinephrine, dopamine, α-2-macroglobulin, proteins involved in immune response, lipid metabolism and oxidative stress, apolipoprotein superfamily, and others were shown to be biomarkers in PD. For AD as potential biomarkers, there are: lipocalin-1, lysozyme-C, and lacritin, amyloid proteins, t-Tau, p-Tau; for MS there are: oligoclonal bands, lipids containing choline, free carnitine, acylcarnitines, and some amino acids. Information systematized in this review provides interesting data and new insight to help improve clinical outcomes for patients with neurodegenerative disorders.
Collapse
Affiliation(s)
- Angelika Król-Grzymała
- Faculty of Biology and Biotechnology, University of Warmia and Mazury, 10-719 Olsztyn, Poland
| | | | - Ewa Fiedorowicz
- Faculty of Biology and Biotechnology, University of Warmia and Mazury, 10-719 Olsztyn, Poland
| | - Dominika Rozmus
- Faculty of Biology and Biotechnology, University of Warmia and Mazury, 10-719 Olsztyn, Poland
| | - Anna Cieślińska
- Faculty of Biology and Biotechnology, University of Warmia and Mazury, 10-719 Olsztyn, Poland
| | - Andrzej Grzybowski
- Department of Ophthalmology, University of Warmia and Mazury, 10-719 Olsztyn, Poland
- Institute for Research in Ophthalmology, Foundation for Ophthalmology Development, 61-553 Poznan, Poland
| |
Collapse
|
13
|
Opportunities and challenges of alpha-synuclein as a potential biomarker for Parkinson's disease and other synucleinopathies. NPJ Parkinsons Dis 2022; 8:93. [PMID: 35869066 PMCID: PMC9307631 DOI: 10.1038/s41531-022-00357-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 06/24/2022] [Indexed: 02/07/2023] Open
Abstract
Parkinson’s disease (PD), the second most common progressive neurodegenerative disease, develops and progresses for 10–15 years before the clinical diagnostic symptoms of the disease are manifested. Furthermore, several aspects of PD pathology overlap with other neurodegenerative diseases (NDDs) linked to alpha-synuclein (aSyn) aggregation, also called synucleinopathies. Therefore, there is an urgent need to discover and validate early diagnostic and prognostic markers that reflect disease pathophysiology, progression, severity, and potential differences in disease mechanisms between PD and other NDDs. The close association between aSyn and the development of pathology in synucleinopathies, along with the identification of aSyn species in biological fluids, has led to increasing interest in aSyn species as potential biomarkers for early diagnosis of PD and differentiate it from other synucleinopathies. In this review, we (1) provide an overview of the progress toward mapping the distribution of aSyn species in the brain, peripheral tissues, and biological fluids; (2) present comparative and critical analysis of previous studies that measured total aSyn as well as other species such as modified and aggregated forms of aSyn in different biological fluids; and (3) highlight conceptual and technical gaps and challenges that could hinder the development and validation of reliable aSyn biomarkers; and (4) outline a series of recommendations to address these challenges. Finally, we propose a combined biomarker approach based on integrating biochemical, aggregation and structure features of aSyn, in addition to other biomarkers of neurodegeneration. We believe that capturing the diversity of aSyn species is essential to develop robust assays and diagnostics for early detection, patient stratification, monitoring of disease progression, and differentiation between synucleinopathies. This could transform clinical trial design and implementation, accelerate the development of new therapies, and improve clinical decisions and treatment strategies.
Collapse
|
14
|
Lin CW, Lai TT, Chen SJ, Lin CH. Elevated α-synuclein and NfL levels in tear fluids and decreased retinal microvascular densities in patients with Parkinson's disease. GeroScience 2022; 44:1551-1562. [PMID: 35484471 DOI: 10.1007/s11357-022-00576-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 04/19/2022] [Indexed: 12/21/2022] Open
Abstract
The pathognomonic hallmark of Parkinson's disease (PD), α-synuclein, has been observed in the retina of PD patients. We investigated whether biomarkers in the tears and retinal microvascular changes associate with PD risk and progression. This prospective study enrolled 49 PD patients and 45 age-matched healthy controls. The α-synuclein and neurofilament light chain (NfL) levels were measured using an electrochemiluminescence immunoassay. Retinal vessel density was assessed using optical coherence tomography angiography (OCT-A). The Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) and Mini-Mental State Examination score were used to assess motor and cognitive progression. The α-synuclein and NfL levels in the tears were higher in PD patients than in controls (α-synuclein: 55.49 ± 8.12 pg/mL vs. 31.71 ± 3.25 pg/mL, P = 0.009; NfL: 2.89 ± 0.52 pg/mL vs. 1.47 ± 0.23 pg/mL, P = 0.02). The vessel densities in the deep plexus of central macula and the radial peripapillary capillary layer of disc region were lower in PD patients with moderate-stage compared with early-stage PD (P < 0.05). The accuracy of predicting PD occurrence using age and sex alone (area under the curve [AUC] 0.612) was significantly improved by adding α-synuclein and NfL levels and retinal vascular densities (AUC 0.752, P = 0.001). After a mean follow-up of 1.5 ± 0.3 years, the accuracy of predicting motor or cognitive progression using age, sex, and baseline motor severity as a basic model was increased by incorporating retinal microvascular and biofluid markers as a full model (P = 0.001). Our results showed that retinal microvascular densities combined with α-synuclein and NfL levels in tears are associated with risk and progression of PD.
Collapse
Affiliation(s)
- Chao-Wen Lin
- Department of Ophthalmology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Tzu-Ting Lai
- Department of Ophthalmology, En Chu Kong Hospital, New Taipei City, Taiwan
| | - Szu-Ju Chen
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, 100, Taiwan.,Department of Neurology, National Taiwan University Hospital Bei-Hu Branch, Taipei, Taiwan
| | - Chin-Hsien Lin
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, 100, Taiwan.
| |
Collapse
|
15
|
Kakan SS, Edman MC, Yao A, Okamoto CT, Nguyen A, Hjelm BE, Hamm-Alvarez SF. Tear miRNAs Identified in a Murine Model of Sjögren’s Syndrome as Potential Diagnostic Biomarkers and Indicators of Disease Mechanism. Front Immunol 2022; 13:833254. [PMID: 35309364 PMCID: PMC8931289 DOI: 10.3389/fimmu.2022.833254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 02/01/2022] [Indexed: 11/13/2022] Open
Abstract
ObjectiveThe tear miRNAome of the male NOD mouse, a model of ocular symptoms of Sjögren’s syndrome (SS), was analyzed to identify unique miRNAs.MethodsMale NOD mice, aged 12-14 weeks, were used to identify tear miRNAs associated with development of autoimmune dacryoadenitis. Age- and sex-matched male BALB/c mice served as healthy controls while age-matched female NOD mice that do not develop the autoimmune dacryoadenitis characteristic of SS were used as additional controls. Total RNA was isolated from stimulated tears pooled from 5 mice per sample and tear miRNAs were sequenced and analyzed. Putative miRNA hits were validated in additional mouse cohorts as well as in tears of SS patients versus patients with another form of dry eye disease, meibomian gland disease (MGD) using qRT-PCR. The pathways influenced by the validated hits were identified using Ingenuity Pathway Analysis.ResultsIn comparison to tears from both healthy (male BALB/c) and additional control (female NOD) mice, initial analy1sis identified 7 upregulated and 7 downregulated miRNAs in male NOD mouse tears. Of these, 8 were validated by RT-qPCR in tears from additional mouse cohorts. miRNAs previously implicated in SS pathology included mmu-miR-146a/b-5p, which were significantly downregulated, as well as mmu-miR-150-5p and mmu-miR-181a-5p, which were upregulated in male NOD mouse tears. All other validated hits including the upregulated miR-181b-5p and mmu-miR-203-3p, as well as the downregulated mmu-miR-322-5p and mmu-miR-503-5p, represent novel putative indicators of autoimmune dacryoadenitis in SS. When compared to tears from patients with MGD, miRNAs hsa-miR-203a-3p, hsa-miR-181a-5p and hsa-miR-181b-5p were also significantly increased in tears of SS patients.ConclusionsA panel of differentially expressed miRNAs were identified in tears of male NOD mice, with some preliminary validation in SS patients, including some never previously linked to SS. These may have potential utility as indicators of ocular symptoms of SS; evaluation of the pathways influenced by these dysregulated miRNAs may also provide further insights into SS pathogenesis.
Collapse
Affiliation(s)
- Shruti Singh Kakan
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
- Department of Ophthalmology, Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Maria C. Edman
- Department of Ophthalmology, Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Alexander Yao
- Department of Ophthalmology, Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Curtis T. Okamoto
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Annie Nguyen
- Department of Ophthalmology, Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Brooke E. Hjelm
- Department of Translational Genomics, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
- *Correspondence: Sarah F. Hamm-Alvarez, ; Brooke E. Hjelm,
| | - Sarah F. Hamm-Alvarez
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
- Department of Ophthalmology, Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
- *Correspondence: Sarah F. Hamm-Alvarez, ; Brooke E. Hjelm,
| |
Collapse
|
16
|
Oliveira JT, Dakic V, Vitória G, Pedrosa CDS, Mendes M, Aragão LGH, Cardim-Pires TR, Lelièvre D, Furtado DR, Pinheiro RO, Foguel D, Breton L, Bouez C, De Vecchi R, Guimarães MZP, Rehen S. Oligomeric α-Synuclein induces skin degeneration in reconstructed human epidermis. Neurobiol Aging 2022; 113:108-117. [DOI: 10.1016/j.neurobiolaging.2022.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 02/18/2022] [Accepted: 02/19/2022] [Indexed: 10/19/2022]
|
17
|
Nandi SK, Singh D, Upadhay J, Gupta N, Dhiman N, Mittal SK, Mahindroo N. Identification of tear-based protein and non-protein biomarkers: Its application in diagnosis of human diseases using biosensors. Int J Biol Macromol 2021; 193:838-846. [PMID: 34728300 DOI: 10.1016/j.ijbiomac.2021.10.198] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 09/30/2021] [Accepted: 10/26/2021] [Indexed: 12/27/2022]
Abstract
Discovery of robust, selective and specific biomarkers are important for early diagnosis and monitor progression of human diseases. Eye being a common target for several human diseases, vision impediment and complications are often associated with systemic and ocular diseases. Tears are bodily fluids that are closest to eye and are rich in protein content and other metabolites. As a biomarker repository, it advantages over other bodily fluids due to the ability to collect it non-invasively. In this review, we highlight some recent advancements in identification of tear-based protein biomarkers like lacryglobin and cystatin SA for cancer; interleukin-6 and immunoglobulin-A antibody for COVID-19; tau, amyloid-β-42 and lysozyme-C for Alzheimer's disease; peroxiredoxin-6 and α-synuclein for Parkinson's disease; kallikrein, angiotensin converting enzyme and lipocalin-1 for glaucoma; lactotransferrin and lipophilin-A for diabetic retinopathy and zinc-alpha-2 glycoprotein-1, prolactin and calcium binding protein-A4 for eye thyroid disease. We also discussed identification of tear based non-protein biomarkers like lysophospholipids and acetylcarnitine for glaucoma, 8-hydroxy-2'-deoxyquanosine and malondialdehyde for thyroid eye disease. We elucidate technological advancement in developing tear-based biosensors for diagnosis and monitoring diseases such as diabetes, diabetic retinopathy and Alzheimer's disease. Altogether, the study of tears as potential biomarkers for early diagnosis of human diseases is promising.
Collapse
Affiliation(s)
- Sandip K Nandi
- School of Health Sciences, University of Petroleum and Energy Studies, Dehradun, Uttarakhand 248007, India.
| | - Deepanmol Singh
- School of Health Sciences, University of Petroleum and Energy Studies, Dehradun, Uttarakhand 248007, India
| | - Jyoti Upadhay
- School of Health Sciences, University of Petroleum and Energy Studies, Dehradun, Uttarakhand 248007, India
| | - Neeti Gupta
- Department of Ophthalmology, All India Institute of Medical Sciences, Rishikesh 249203, India
| | - Nayan Dhiman
- School of Health Sciences, University of Petroleum and Energy Studies, Dehradun, Uttarakhand 248007, India
| | - Sanjeev Kumar Mittal
- Department of Ophthalmology, All India Institute of Medical Sciences, Rishikesh 249203, India
| | - Neeraj Mahindroo
- School of Health Sciences, University of Petroleum and Energy Studies, Dehradun, Uttarakhand 248007, India.
| |
Collapse
|
18
|
Abstract
There has been increasing interest in finding non-invasive biomarkers for neurodegenerative diseases such as Alzheimer's disease (AD). This observational study investigated AD-specific biomarkers in tear fluid. Tear fluid was collected from a total of 65 subjects, including 23 patients with subjective cognitive decline (SCD), 22 patients with mild cognitive impairment (MCI), 11 dementia patients and 9 healthy controls (HC). Levels of amyloid-beta peptides (AB38, AB40, AB42), total-tau (t-tau) and phosphorylated-tau (p-tau) were determined using multiplex immunoassays. Levels of AB40 and t-tau were detectable in the vast majority (> 94%) of tear fluid samples. Cerebrospinal fluid (CSF) was available from a subset of patients. In this group, tear t-tau levels were significantly higher in people with dementia compared to SCD patients. Tear t-tau levels were elevated in patients with neurodegeneration (classified according to the A/T/N system) compared to patients without neurodegeneration. Negative correlations were found between CSF AB42 and CSF t-tau, and between CSF AB42 and tear t-tau. In summary, this study shows the potential of tau proteins in tear fluid to be associated with disease severity and neurodegeneration.
Collapse
|
19
|
Gijs M, Ramakers IHGB, Visser PJ, Verhey FRJ, van de Waarenburg MPH, Schalkwijk CG, Nuijts RMMA, Webers CAB. Association of tear fluid amyloid and tau levels with disease severity and neurodegeneration. Sci Rep 2021; 11:22675. [PMID: 34811435 PMCID: PMC8608861 DOI: 10.1038/s41598-021-01993-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 11/08/2021] [Indexed: 02/07/2023] Open
Abstract
There has been increasing interest in finding non-invasive biomarkers for neurodegenerative diseases such as Alzheimer's disease (AD). This observational study investigated AD-specific biomarkers in tear fluid. Tear fluid was collected from a total of 65 subjects, including 23 patients with subjective cognitive decline (SCD), 22 patients with mild cognitive impairment (MCI), 11 dementia patients and 9 healthy controls (HC). Levels of amyloid-beta peptides (AB38, AB40, AB42), total-tau (t-tau) and phosphorylated-tau (p-tau) were determined using multiplex immunoassays. Levels of AB40 and t-tau were detectable in the vast majority (> 94%) of tear fluid samples. Cerebrospinal fluid (CSF) was available from a subset of patients. In this group, tear t-tau levels were significantly higher in people with dementia compared to SCD patients. Tear t-tau levels were elevated in patients with neurodegeneration (classified according to the A/T/N system) compared to patients without neurodegeneration. Negative correlations were found between CSF AB42 and CSF t-tau, and between CSF AB42 and tear t-tau. In summary, this study shows the potential of tau proteins in tear fluid to be associated with disease severity and neurodegeneration.
Collapse
Affiliation(s)
- Marlies Gijs
- University Eye Clinic Maastricht, Maastricht University Medical Center (MUMC+), School for Mental Health and Neuroscience, Maastricht University, P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands.
| | - Inez H G B Ramakers
- Department of Psychiatry and Neuropsychology, Alzheimer Center Limburg, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Pieter Jelle Visser
- Department of Psychiatry and Neuropsychology, Alzheimer Center Limburg, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.,Department of Neurology, Alzheimer Center Amsterdam, Vrije Universiteit Medical Center, Neuroscience Campus Amsterdam, Amsterdam, The Netherlands
| | - Frans R J Verhey
- Department of Psychiatry and Neuropsychology, Alzheimer Center Limburg, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Marjo P H van de Waarenburg
- Department of Internal Medicine, School for Cardiovascular Diseases (CARIM), Maastricht University Medical Center, Maastricht, The Netherlands
| | - Casper G Schalkwijk
- Department of Internal Medicine, School for Cardiovascular Diseases (CARIM), Maastricht University Medical Center, Maastricht, The Netherlands
| | - Rudy M M A Nuijts
- University Eye Clinic Maastricht, Maastricht University Medical Center (MUMC+), School for Mental Health and Neuroscience, Maastricht University, P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands
| | - Carroll A B Webers
- University Eye Clinic Maastricht, Maastricht University Medical Center (MUMC+), School for Mental Health and Neuroscience, Maastricht University, P. Debyelaan 25, 6229 HX, Maastricht, The Netherlands
| |
Collapse
|
20
|
Alotaibi S, Markoulli M, Ozkan J, Papas E. Bio-chemical markers of chronic, non-infectious disease in the human tear film. Clin Exp Optom 2021; 105:166-176. [PMID: 34592130 DOI: 10.1080/08164622.2021.1974282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
The tear film is a thin, moist layer covering the ocular surface and is laden with proteins, peptides, lipids, mucins, electrolytes and cellular debris which function to maintain the healthy status of the ocular surface. In many cases of ocular or systemic disease, the integrity of this layer is changed and/or the balance of its constituents is disturbed. Since tears are easy and quick to collect and can be stored for long periods, they have the potential to be a valuable source of information relevant to many disease states. The purpose of this review is to collate information on the known biomarkers of systemic disease that have been identified in tears. The range of conditions covered includes diabetes mellitus, diabetic retinopathy, diabetic peripheral neuropathy, multiple sclerosis, Parkinson's disease, Alzheimer's disease, migraine, systemic sclerosis, cystic fibrosis, thyroid disorders and cancer.
Collapse
Affiliation(s)
- Sultan Alotaibi
- Department of Optometry & Vision Science, University of New South Wales, Sydney, Australia.,King Saud University, Riyadh, Saudi Arabia
| | - Maria Markoulli
- Department of Optometry & Vision Science, University of New South Wales, Sydney, Australia
| | - Jerome Ozkan
- Department of Optometry & Vision Science, University of New South Wales, Sydney, Australia
| | - Eric Papas
- Department of Optometry & Vision Science, University of New South Wales, Sydney, Australia
| |
Collapse
|
21
|
Non-invasive wearable chemical sensors in real-life applications. Anal Chim Acta 2021; 1179:338643. [PMID: 34535258 DOI: 10.1016/j.aca.2021.338643] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 05/05/2021] [Accepted: 05/10/2021] [Indexed: 12/23/2022]
Abstract
Over the past decade, non-invasive wearable chemical sensors have gained tremendous attention in the field of personal health monitoring and medical diagnosis. These sensors provide non-invasive, real-time, and continuous monitoring of targeted biomarkers with more simplicity than the conventional diagnostic approaches. This review primarily describes the substrate materials used for sensor fabrication, sample collection and handling, and analytical detection techniques that are utilized to detect biomarkers in different biofluids. Common substrates including paper, textile, and hydrogel for wearable sensor fabrication are discussed. Principles and applications of colorimetric and electrochemical detection in wearable chemical sensors are illustrated. Data transmission systems enabling wireless communication between the sensor and output devices are also discussed. Finally, examples of different designs of wearable chemical sensors including tattoos, garments, and accessories are shown. Successful development of non-invasive wearable chemical sensors will effectively help users to manage their personal health, predict the potential diseases, and eventually improve the overall quality of life.
Collapse
|
22
|
Chalkias IN, Tegos T, Topouzis F, Tsolaki M. Ocular biomarkers and their role in the early diagnosis of neurocognitive disorders. Eur J Ophthalmol 2021; 31:2808-2817. [PMID: 34000876 DOI: 10.1177/11206721211016311] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Given the fact that different types of dementia can be diagnosed only postmortem or when the disease has progressed enough to cause irreversible damage to certain brain areas, there has been an increasing need for the development of sensitive and reliable methods that can detect early preclinical forms of dementia, before the symptoms have even appeared. Ideally, such a method would have the following characteristics: to be inexpensive, sensitive and specific, Non-invasive, fast and easily accessible. The ophthalmologic examination and especially the study of the retina, has caught the attention of many researchers, as it can provide a lot of information about the CNS and it fulfills many of the aforementioned criteria. Since the introduction of the non-invasive optical coherence tomography (OCT) and the newly developed modality OCT-angiography (OCT-A) that can demonstrate the structure and the microvasculature of the retina and choroid, respectively, there have been promising results regarding the value of the ophthalmologic examination in the early diagnosis of Alzheimer's disease. In this review paper, we summarize and discuss the ocular findings in patients with cognitive impairment disorders and we highlight the importance of the ophthalmologic examination to the diagnosis of these disorders.
Collapse
Affiliation(s)
- Ioannis-Nikolaos Chalkias
- 1st Department of Ophthalmology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Makedonia Thraki, Greece
| | - Thomas Tegos
- 1st Department of Neurology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Makedonia Thraki, Greece
| | - Fotis Topouzis
- 1st Department of Ophthalmology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Makedonia Thraki, Greece
| | - Magda Tsolaki
- 1st Department of Neurology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Makedonia Thraki, Greece.,Greek Association of Alzheimer's Disease and Related Disorders, Thessaloniki, Greece
| |
Collapse
|
23
|
Bogdanov V, Kim A, Nodel M, Pavlenko T, Pavlova E, Blokhin V, Chesnokova N, Ugrumov M. A Pilot Study of Changes in the Level of Catecholamines and the Activity of α-2-Macroglobulin in the Tear Fluid of Patients with Parkinson's Disease and Parkinsonian Mice. Int J Mol Sci 2021; 22:ijms22094736. [PMID: 33947010 PMCID: PMC8125625 DOI: 10.3390/ijms22094736] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 04/27/2021] [Accepted: 04/28/2021] [Indexed: 12/19/2022] Open
Abstract
Development of differential and early (preclinical) diagnostics of Parkinson’s disease (PD) is among the priorities in neuroscience. We searched for changes in the level of catecholamines and α-2-macroglobulin activity in the tear fluid (TF) in PD patients at an early clinical stage. It was shown that TF in patients is characterized by an increased level of noradrenaline mainly on the ipsilateral side of pronounced motor symptoms (72%, p = 0.049), a decreased level of adrenaline on both sides (ipsilateral—53%, p = 0.004; contralateral—42%, p = 0.02), and an increased α-2-macroglobulin activity on both sides (ipsilateral—53%, p = 0.03; contralateral—56%, p = 0.037) compared to controls. These changes are considered as potential biomarkers for differential diagnosis. Similar changes in the TF were found in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice when modeling clinical and preclinical stages of PD. These data show the adequacy of models to the pathogenesis of PD along the selected metabolic pathways, and also suggest that the found TF changes can be considered as potential biomarkers for preclinical diagnosis of PD. In Parkinsonian mice, the level of catecholamines also changes in the lacrimal glands, which makes it possible to consider them as one of the sources of catecholamines in the TF.
Collapse
Affiliation(s)
- Vsevolod Bogdanov
- Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, 26 Vavilova Street, 119334 Moscow, Russia; (V.B.); (A.K.); (E.P.); (V.B.)
| | - Alexander Kim
- Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, 26 Vavilova Street, 119334 Moscow, Russia; (V.B.); (A.K.); (E.P.); (V.B.)
| | - Marina Nodel
- Sechenov First Moscow State Medical University of the Ministry of Health of the Russian Federation, 8/2 Trubetskaya Street, 119991 Moscow, Russia;
- Russian Clinical and Research Center of Gerontology, 16 1st Leonova Street, 129226 Moscow, Russia
| | - Tatiana Pavlenko
- Helmholtz Moscow Research Institute of Eye Diseases of the Ministry of Health of the Russian Federation, 14/19 Sadovaya-Chernogryazskaya Street, 105062 Moscow, Russia; (T.P.); (N.C.)
| | - Ekaterina Pavlova
- Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, 26 Vavilova Street, 119334 Moscow, Russia; (V.B.); (A.K.); (E.P.); (V.B.)
| | - Victor Blokhin
- Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, 26 Vavilova Street, 119334 Moscow, Russia; (V.B.); (A.K.); (E.P.); (V.B.)
| | - Natalia Chesnokova
- Helmholtz Moscow Research Institute of Eye Diseases of the Ministry of Health of the Russian Federation, 14/19 Sadovaya-Chernogryazskaya Street, 105062 Moscow, Russia; (T.P.); (N.C.)
| | - Michael Ugrumov
- Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, 26 Vavilova Street, 119334 Moscow, Russia; (V.B.); (A.K.); (E.P.); (V.B.)
- Correspondence:
| |
Collapse
|
24
|
Du T, Wang L, Liu W, Zhu G, Chen Y, Zhang J. Biomarkers and the Role of α-Synuclein in Parkinson's Disease. Front Aging Neurosci 2021; 13:645996. [PMID: 33833675 PMCID: PMC8021696 DOI: 10.3389/fnagi.2021.645996] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 03/05/2021] [Indexed: 12/13/2022] Open
Abstract
Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by the presence of α-synuclein (α-Syn)-rich Lewy bodies (LBs) and the preferential loss of dopaminergic (DA) neurons in the substantia nigra (SN) pars compacta (SNpc). However, the widespread involvement of other central nervous systems (CNS) structures and peripheral tissues is now widely documented. The onset of the molecular and cellular neuropathology of PD likely occurs decades before the onset of the motor symptoms characteristic of PD, so early diagnosis of PD and adequate tracking of disease progression could significantly improve outcomes for patients. Because the clinical diagnosis of PD is challenging, misdiagnosis is common, which highlights the need for disease-specific and early-stage biomarkers. This review article aims to summarize useful biomarkers for the diagnosis of PD, as well as the biomarkers used to monitor disease progression. This review article describes the role of α-Syn in PD and how it could potentially be used as a biomarker for PD. Also, preclinical and clinical investigations encompassing genetics, immunology, fluid and tissue, imaging, as well as neurophysiology biomarkers are discussed. Knowledge of the novel biomarkers for preclinical detection and clinical evaluation will contribute to a deeper understanding of the disease mechanism, which should more effectively guide clinical applications.
Collapse
Affiliation(s)
- Tingting Du
- Department of Functional Neurosurgery, Beijing Neurosurgical Institute, Capital Medical University, Beijing, China
| | - Le Wang
- Molecular Biology Laboratory for Neuropsychiatric Diseases, Department of Neurobiology, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
| | - Weijin Liu
- Key Laboratory for Neurodegenerative Disease of the Ministry of Education, Key Laboratory of Neural Regeneration and Repair, Beijing Key Laboratory on Parkinson's Disease, Department of Neurobiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Guanyu Zhu
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Yingchuan Chen
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Jianguo Zhang
- Department of Functional Neurosurgery, Beijing Neurosurgical Institute, Capital Medical University, Beijing, China.,Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Neurostimulation, Beijing Municipal Science and Technology Commission, Beijing, China
| |
Collapse
|
25
|
Biomarkers in Tears and Ocular Surface: A Window for Neurodegenerative Diseases. Eye Contact Lens 2021; 46 Suppl 2:S129-S134. [PMID: 31658175 DOI: 10.1097/icl.0000000000000663] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVES The purpose of this review is to briefly outline current scientific evidence on the potential role of tear analysis and ocular surface evaluation in diagnosis and monitoring of neurodegenerative diseases, especially Alzheimer disease, Parkinson disease, and glaucoma. METHODS A systematic computerized search in the electronic databases PubMed, MEDLINE, and the Cochrane Collaborations was conducted to find eligible articles which their main topic was to investigate the tear and ocular surface in neurodegenerative diseases. After a first screening of titles and abstracts and a full-text review, 26 articles met the inclusion criteria (1 about the neurodegenerative diseases, 3 about the Alzheimer disease, 11 about the Parkinson disease, 11 about glaucoma, and 1 about amyotrophic lateral sclerosis). RESULTS The ocular surface picture seems to be altered in the setting of neurodegenerative diseases with specific characteristics according to each disease. They seem to be associated with reduced corneal sensitivity and abnormal tear function, and each one presents the expression of specific biomarkers in tears. CONCLUSIONS The study of tears and ocular surface appears to be a new and noninvasive promising way to assist in the diagnosis and monitoring of neurodegenerative diseases.
Collapse
|
26
|
Schlichtmann BW, Kondru N, Hepker MM, Kanthasamy AG, Anantharam V, John M, Ban B, Mallapragada SK, Narasimhan B. Enzyme Immunoassay-Based Platform for Accurate Detection of Serum Pathological α-Synuclein in Parkinson's Disease Patients. ACS Chem Neurosci 2020; 11:4179-4190. [PMID: 33196164 DOI: 10.1021/acschemneuro.0c00461] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
An assay for accurately diagnosing early stage Parkinson's Disease (PD) is currently unavailable, and therefore, there is an urgent and unmet need. Such a diagnostic assay will enable prompt institution of appropriate supportive management measures to prevent rapid deterioration of disease and improve both quality of life and life expectancy of PD patients. A reliable assay platform will also be of great benefit to drug discovery and drug development in the area of PD. To this end, we describe the development of two indirect, competitive, semiquantitative enzyme immunoassays (EIAs), each employing a disparate singularly specific mouse monoclonal antibody (ssMAb) against pathological aggregates of human α-Synuclein (αSynagg), a well-established biomarker pathognomonic of PD. Our results demonstrate that these EIAs in tandem accurately discriminated between αSynagg serum concentrations from PD patients and age-matched healthy control (HC) individuals (PD = 1700 ± 220 ng/mL; HC = 870 ± 120 ng/mL with an overall sensitivity of 56%, specificity of 63%, positive predictive value of 60%, and negative predictive value of 59%). The limits of detection of αSynagg were 400 and 300 pg/mL for ssMAbs 3C5 and 5H6, respectively. These tandem EIAs have the potential to add to the repertoire of tools for earlier diagnosis of this debilitating disorder, as well as for drug development strategies.
Collapse
Affiliation(s)
- Benjamin W Schlichtmann
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011, United States
- Nanovaccine Institute, Ames, Iowa 50011, United States
| | - Naveen Kondru
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa 50011, United States
| | - Monica M Hepker
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa 50011, United States
| | - Anumantha G Kanthasamy
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa 50011, United States
- Nanovaccine Institute, Ames, Iowa 50011, United States
| | - Vellareddy Anantharam
- PK Biosciences Corporation, Ames, Iowa 50011, United States
- Nanovaccine Institute, Ames, Iowa 50011, United States
| | - Manohar John
- PathoVacs, Incorporated, Ames, Iowa 50011, United States
- Nanovaccine Institute, Ames, Iowa 50011, United States
| | - Bhupal Ban
- Indiana Biosciences Research Institute (IBRI), Indianapolis, Indiana 46202, United States
| | - Surya K Mallapragada
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011, United States
- Nanovaccine Institute, Ames, Iowa 50011, United States
| | - Balaji Narasimhan
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011, United States
- Nanovaccine Institute, Ames, Iowa 50011, United States
| |
Collapse
|
27
|
Kumar ST, Jagannath S, Francois C, Vanderstichele H, Stoops E, Lashuel HA. How specific are the conformation-specific α-synuclein antibodies? Characterization and validation of 16 α-synuclein conformation-specific antibodies using well-characterized preparations of α-synuclein monomers, fibrils and oligomers with distinct structures and morphology. Neurobiol Dis 2020; 146:105086. [PMID: 32971232 DOI: 10.1016/j.nbd.2020.105086] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 08/30/2020] [Accepted: 09/17/2020] [Indexed: 12/14/2022] Open
Abstract
Increasing evidence suggests that alpha-synuclein (α-syn) oligomers are obligate intermediates in the pathway involved in α-syn fibrillization and Lewy body (LB) formation, and may also accumulate within LBs in Parkinson's disease (PD) and other synucleinopathies. Therefore, the development of tools and methods to detect and quantify α-syn oligomers has become increasingly crucial for mechanistic studies to understand their role in PD, and to develop new diagnostic methods and therapies for PD and other synucleinopathies. The majority of these tools and methods rely primarily on the use of aggregation state-specific or conformation-specific antibodies. Given the impact of the data and knowledge generated using these antibodies on shaping the foundation and directions of α-syn and PD research, it is crucial that these antibodies are thoroughly characterized, and their specificity or ability to capture diverse α-syn species is tested and validated. Herein, we describe an antibody characterization and validation pipeline that allows a systematic investigation of the specificity of α-syn antibodies using well-defined and well-characterized preparations of various α-syn species, including monomers, fibrils, and different oligomer preparations that are characterized by distinct morphological, chemical and secondary structure properties. This pipeline was used to characterize 18 α-syn antibodies, 16 of which have been reported as conformation- or oligomer-specific antibodies, using an array of techniques, including immunoblot analysis (slot blot and Western blot), a digital ELISA assay using single molecule array technology and surface plasmon resonance. Our results show that i) none of the antibodies tested are specific for one particular type of α-syn species, including monomers, oligomers or fibrils; ii) all antibodies that were reported to be oligomer-specific also recognized fibrillar α-syn; and iii) a few antibodies showed high specificity for oligomers and fibrils but did not bind to monomers. These findings suggest that the great majority of α-syn aggregate-specific antibodies do not differentiate between oligomers and fibrils, thus highlighting the importance of exercising caution when interpreting results obtained using these antibodies. Our results also underscore the critical importance of the characterization and validation of antibodies before their use in mechanistic studies and as diagnostic tools or therapeutic agents. This will not only improve the quality and reproducibility of research and reduce costs but will also reduce the number of therapeutic antibody failures in the clinic.
Collapse
Affiliation(s)
- Senthil T Kumar
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, EPFL, Switzerland
| | - Somanath Jagannath
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, EPFL, Switzerland
| | | | - Hugo Vanderstichele
- ADx NeuroSciences, Technologiepark 94, Ghent, Belgium; Biomarkable, Gent, Belgium
| | - Erik Stoops
- ADx NeuroSciences, Technologiepark 94, Ghent, Belgium
| | - Hilal A Lashuel
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, EPFL, Switzerland.
| |
Collapse
|
28
|
Maass F, Rikker S, Dambeck V, Warth C, Tatenhorst L, Csoti I, Schmitz M, Zerr I, Leha A, Bähr M, Lingor P. Increased alpha-synuclein tear fluid levels in patients with Parkinson's disease. Sci Rep 2020; 10:8507. [PMID: 32444780 PMCID: PMC7244583 DOI: 10.1038/s41598-020-65503-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 05/05/2020] [Indexed: 12/13/2022] Open
Abstract
The objective of the study was to estimate if altered levels of alpha-synuclein can be detected in tear fluid of patients with Parkinson’s disease (PD). Therefore, tear fluid samples of 75 PD patients, 75 control subjects and 31 atypical Parkinsonian patients were collected and analyzed in triplicates using an ultra-sensitive single molecule array (SIMOA) system and applying a human alpha-synuclein immunoassay. In PD, levels of total soluble alpha-synuclein were significantly increased compared to control subjects (p = 0.03; AUC PD vs. controls 0.60). There was no difference comparing PD patients stratified by Hoehn & Yahr stages and atypical Parkinsonian syndromes stratified by tauopathies and non-PD-synucleinopathies against each other (p > 0.05). In conclusion, alpha-synuclein can be detected and quantified in tear fluid, revealing small but significant differences in total alpha-synuclein levels between PD and control subjects. Tear fluid can be collected non-invasively and risk-free, therefore presenting a promising source for further biomarker research.
Collapse
Affiliation(s)
- Fabian Maass
- Department of Neurology, University Medical Center, Göttingen, Germany.
| | - Sebastian Rikker
- Department of Neurology, University Medical Center, Göttingen, Germany
| | - Vivian Dambeck
- Department of Neurology, University Medical Center, Göttingen, Germany.,Cluster of Excellence Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration (BIN), University Medical Center, Göttingen, Germany
| | - Carmina Warth
- Department of Neurology, University Medical Center, Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration (BIN), University Medical Center, Göttingen, Germany
| | - Lars Tatenhorst
- Department of Neurology, University Medical Center, Göttingen, Germany.,DZNE, German Center for Neurodegenerative Diseases, Munich and Göttingen, Germany.,Cluster of Excellence Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration (BIN), University Medical Center, Göttingen, Germany
| | - Ilona Csoti
- Gertrudis Clinic Parkinson-Center, Biskirchen, Germany
| | - Matthias Schmitz
- Department of Neurology, University Medical Center, Göttingen, Germany.,DZNE, German Center for Neurodegenerative Diseases, Munich and Göttingen, Germany
| | - Inga Zerr
- Department of Neurology, University Medical Center, Göttingen, Germany.,DZNE, German Center for Neurodegenerative Diseases, Munich and Göttingen, Germany
| | - Andreas Leha
- Department of Medical Statistics, University Medical Center, Göttingen, Germany
| | - Mathias Bähr
- Department of Neurology, University Medical Center, Göttingen, Germany.,Cluster of Excellence Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
| | - Paul Lingor
- Department of Neurology, University Medical Center, Göttingen, Germany.,DZNE, German Center for Neurodegenerative Diseases, Munich and Göttingen, Germany.,Cluster of Excellence Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration (BIN), University Medical Center, Göttingen, Germany.,Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Department of Neurology, 81675, Munich, Germany
| |
Collapse
|
29
|
Pavlenko TA, Chesnokova NB, Nodel MR, Kim AR, Ugrumov MV. Molecular Mechanisms and Clinical Manifestations of Catecholamine Dysfunction in the Eye in Parkinson's Disease As a Basis for Developing Early Diagnosis. Acta Naturae 2020; 12:52-62. [PMID: 32742727 PMCID: PMC7385097 DOI: 10.32607/actanaturae.10906] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 04/16/2020] [Indexed: 01/08/2023] Open
Abstract
This review provides information on the non-motor peripheral manifestations of Parkinson's disease (PD) associated with a pathology of the visual analyzer and the auxiliary apparatus of the eye. The relationship between neurodegenerative processes that take place in the brain and in the eye opens new prospects to use preventive ophthalmologic examination to diagnose PD long before the characteristic motor symptoms appear. This will encourage the use of neuroprotective therapy, which stops, or at least slows down, neuronal death, instead of the current replacement therapy with dopamine agonists. An important result of an eye examination of patients with PD may be a non-invasive identification of new peripheral biomarkers manifesting themselves as changes in the composition of the lacrimal fluid.
Collapse
Affiliation(s)
- T. A. Pavlenko
- Helmholtz Moscow Research Institute of Eye Diseases of Ministry of Health of the Russian Federation, Moscow, 105062 Russia
| | - N. B. Chesnokova
- Helmholtz Moscow Research Institute of Eye Diseases of Ministry of Health of the Russian Federation, Moscow, 105062 Russia
| | - M. R. Nodel
- Sechenov First Moscow State Medical University, Moscow, 119991 Russia
- Pirogov Russian National Research Medical University, Russian Clinical and Research Center of Gerontology, Moscow, 129226 Russia
| | - A. R. Kim
- Koltzov Institute of Developmental Biology of Russian Academy of Sciences, Moscow, 119334 Russia
| | - M. V. Ugrumov
- Koltzov Institute of Developmental Biology of Russian Academy of Sciences, Moscow, 119334 Russia
| |
Collapse
|
30
|
Edman MC, Janga SR, Kakan SS, Okamoto CT, Freire D, Feigenbaum D, Lew M, Hamm-Alvarez SF. Tears - more to them than meets the eye: why tears are a good source of biomarkers in Parkinson's disease. Biomark Med 2020; 14:151-163. [PMID: 32064896 DOI: 10.2217/bmm-2019-0364] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Tears are a known source of biomarkers for both ocular and systemic diseases with particular advantages; specifically, the noninvasiveness of sample collection and a unique and increasingly better-defined protein composition. Here, we discuss our rationale for use of tears for discovery of biomarkers for Parkinson's disease (PD). These reasons include literature supporting changes in tear flow and composition in PD, and the interconnections between the ocular surface system and neurons affected in PD. We highlight recent data on the identification of tear biomarkers including oligomeric α-synuclein, associated with neuronal degeneration in PD, in tears of PD patients and discuss possible sources for its release into tears. Challenges and next steps for advancing such biomarkers to clinical usage are highlighted.
Collapse
Affiliation(s)
- Maria C Edman
- Department of Ophthalmology and Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Srikanth R Janga
- Department of Ophthalmology and Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Shruti Singh Kakan
- Department of Ophthalmology and Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.,Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, USA
| | - Curtis T Okamoto
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, USA
| | - Daniel Freire
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Danielle Feigenbaum
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Mark Lew
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Sarah F Hamm-Alvarez
- Department of Ophthalmology and Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.,Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, USA
| |
Collapse
|
31
|
Torrington E. Welcome to the 14th volume of Biomarkers in Medicine. Biomark Med 2020; 14:1-4. [PMID: 31904276 DOI: 10.2217/bmm-2019-0595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- Ebony Torrington
- Future Science Group, Unitec House, 2 Albert Place, London, N3 1QB, UK
| |
Collapse
|
32
|
Kim AR, Nodel MR, Pavlenko TA, Chesnokova NB, Yakhno NN, Ugrumov MV. Tear Fluid Catecholamines As Biomarkers of the Parkinson's Disease: A Clinical and Experimental Study. Acta Naturae 2019; 11:99-103. [PMID: 31993241 PMCID: PMC6977954 DOI: 10.32607/20758251-2019-11-4-99-103] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 10/17/2019] [Indexed: 01/10/2023] Open
Abstract
An important approach to an early diagnosis of Parkinson's disease (PD) is screening for peripheral biomarkers in patients at the early clinical stage. In this study, we evaluated catecholamine concentration changes in the tear fluid of untreated PD patients as biomarkers. Norepinephrine and dopamine concentrations in the tear fluid of patients were found to increase compared to those in age controls, which was especially pronounced on the side where motor symptoms appeared. On the contrary, the epinephrine concentration in the tear fluid of patients was reduced bilaterally. Since there was no reason to consider the markers found in the clinical stage of PD as markers of the preclinical stage, we additionally studied the tear fluid composition in mouse neurotoxic models of PD preclinical and clinical stages. The norepinephrine concentration in the tear fluid of mice from the clinical stage model was found to be higher than that in controls; in the preclinical stage model, the norepinephrine concentration had a tendency to increase. Therefore, both PD patients and mice from PD preclinical and clinical stage models manifest unidirectional changes in their tear fluid compositions, which may be considered as promising biomarkers for the development of early diagnosis.
Collapse
Affiliation(s)
- A. R. Kim
- Koltzov Institute of Developmental Biology of Russian Academy of Sciences, Moscow, 119334 Russia
| | - M. R. Nodel
- Sechenov First Moscow State Medical University, Moscow, 119991 Russia
- Pirogov Russian National Research Medical University, Russian Clinical and Research Center of Gerontology, Moscow, 129226 Russia
| | - T. A. Pavlenko
- Helmholtz Moscow Research Institute of Eye Diseases of Ministry of Health of the Russian Federation, Moscow, 105062 Russia
| | - N. B. Chesnokova
- Helmholtz Moscow Research Institute of Eye Diseases of Ministry of Health of the Russian Federation, Moscow, 105062 Russia
| | - N. N. Yakhno
- Sechenov First Moscow State Medical University, Moscow, 119991 Russia
| | - M. V. Ugrumov
- Koltzov Institute of Developmental Biology of Russian Academy of Sciences, Moscow, 119334 Russia
| |
Collapse
|
33
|
Hamm-Alvarez SF, Janga SR, Edman MC, Feigenbaum D, Freire D, Mack WJ, Okamoto CT, Lew MF. Levels of oligomeric α-Synuclein in reflex tears distinguish Parkinson's disease patients from healthy controls. Biomark Med 2019; 13:1447-1457. [PMID: 31552762 DOI: 10.2217/bmm-2019-0315] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: Due to active engagement of sensory and afferent nerve fibers in reflex tearing which could be affected in Parkinson's disease (PD), we tested reflex tears as a source of potential PD biomarkers. Patients & methods: Reflex tears collected from 84 PD and 84 age- and sex-equivalent healthy controls (HC) were used to measure levels of oligomeric α-Syn (α-SynOligo), total α-Syn (α-SynTotal), CCL2, DJ-1, lactoferrin and MMP9. Results: α-synOligo (p < 0.0001), CCL2 (p = 0.003) and lactoferrin (p = 0.002) were significantly elevated in PD patient tears relative to HC tears. Tear flow was significantly lower in PD relative to HC (p = 0.001). Conclusion: Reflex tears are a potential source for detection of characteristic changes in PD patients.
Collapse
Affiliation(s)
- Sarah F Hamm-Alvarez
- Department of Ophthalmology & Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.,Department of Pharmacology & Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, USA
| | - Srikanth R Janga
- Department of Ophthalmology & Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Maria C Edman
- Department of Ophthalmology & Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Danielle Feigenbaum
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Daniel Freire
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Wendy J Mack
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Curtis T Okamoto
- Department of Pharmacology & Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, USA
| | - Mark F Lew
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| |
Collapse
|
34
|
Probiotics for Parkinson's Disease. Int J Mol Sci 2019; 20:ijms20174121. [PMID: 31450864 PMCID: PMC6747430 DOI: 10.3390/ijms20174121] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 08/14/2019] [Accepted: 08/21/2019] [Indexed: 02/08/2023] Open
Abstract
Parkinson’s disease (PD) is a complex neurological disorder classically characterized by impairments in motor system function associated with loss of dopaminergic neurons in the substantia nigra. After almost 200 years since the first description of PD by James Parkinson, unraveling the complexity of PD continues to evolve. It is now recognized that an interplay between genetic and environmental factors influences a diverse range of cellular processes, reflecting on other clinical features including non-motor symptoms. This has consequently highlighted the extensive value of early clinical diagnosis to reduce difficulties of later stage management of PD. Advancement in understanding of PD has made remarkable progress in introducing new tools and strategies such as stem cell therapy and deep brain stimulation. A link between alterations in gut microbiota and PD has also opened a new line. Evidence exists of a bidirectional pathway between the gastrointestinal tract and the central nervous system. Probiotics, prebiotics and synbiotics are being examined that might influence gut-brain axis by altering gut microbiota composition, enteric nervous system, and CNS. This review provides status on use of probiotics for PD. Limitations and future directions will also be addressed to promote further research considering use of probiotics for PD.
Collapse
|
35
|
Zetterberg H, Compta Y. A tear fluid proteome of Parkinson's disease. Parkinsonism Relat Disord 2019; 63:1-2. [PMID: 31353307 DOI: 10.1016/j.parkreldis.2019.07.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Accepted: 07/22/2019] [Indexed: 11/17/2022]
Affiliation(s)
- Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden; Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK; UK Dementia Research Institute at UCL, London, UK
| | - Yaroslau Compta
- Parkinson's disease & Movement Disorders Unit, Neurology Service, Hospital Clínic de Barcelona, Barcelona, Catalonia, Spain; Parkinson's disease and other degenerative movement disorders team, IDIBAPS, CIBERNED, Barcelona, Catalonia, Spain; Institut Clínic de Neurociències (Maria de Maetzu center), Universitat de Barcelona, Barcelona, Catalonia, Spain.
| |
Collapse
|