1
|
Tau as a Biomarker of Neurodegeneration. Int J Mol Sci 2022; 23:ijms23137307. [PMID: 35806324 PMCID: PMC9266883 DOI: 10.3390/ijms23137307] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 06/29/2022] [Accepted: 06/29/2022] [Indexed: 12/13/2022] Open
Abstract
Less than 50 years since tau was first isolated from a porcine brain, its detection in femtolitre concentrations in biological fluids is revolutionizing the diagnosis of neurodegenerative diseases. This review highlights the molecular and technological advances that have catapulted tau from obscurity to the forefront of biomarker diagnostics. Comprehensive updates are provided describing the burgeoning clinical applications of tau as a biomarker of neurodegeneration. For the clinician, tau not only enhances diagnostic accuracy, but holds promise as a predictor of clinical progression, phenotype, and response to drug therapy. For patients living with neurodegenerative disorders, characterization of tau dysregulation could provide much-needed clarity to a notoriously murky diagnostic landscape.
Collapse
|
2
|
Zha GB, Shen M, Gu XS, Yi S. Changes in microtubule-associated protein tau during peripheral nerve injury and regeneration. Neural Regen Res 2016; 11:1506-1511. [PMID: 27857758 PMCID: PMC5090857 DOI: 10.4103/1673-5374.191227] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Tau, a primary component of microtubule-associated protein, promotes microtubule assembly and/or disassembly and maintains the stability of the microtubule structure. Although the importance of tau in neurodegenerative diseases has been well demonstrated, whether tau is involved in peripheral nerve regeneration remains unknown. In the current study, we obtained sciatic nerve tissue from adult rats 0, 1, 4, 7, and 14 days after sciatic nerve crush and examined tau mRNA and protein expression levels and the location of tau in the sciatic nerve following peripheral nerve injury. The results from our quantitative reverse transcription polymerase chain reaction analysis showed that compared with the uninjured control sciatic nerve, mRNA expression levels for both tau and tau tubulin kinase 1, a serine/threonine kinase that regulates tau phosphorylation, were decreased following peripheral nerve injury. Our western blot assay results suggested that the protein expression levels of tau and phosphorylated tau initially decreased 1 day post nerve injury but then gradually increased. The results of our immunohistochemical labeling showed that the location of tau protein was not altered by nerve injury. Thus, these results showed that the expression of tau was changed following sciatic nerve crush, suggesting that tau may be involved in peripheral nerve repair and regeneration.
Collapse
Affiliation(s)
- Guang-Bin Zha
- Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China
| | - Mi Shen
- Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China
| | - Xiao-Song Gu
- Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China
| | - Sheng Yi
- Jiangsu Key Laboratory of Neuroregeneration, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China
| |
Collapse
|
3
|
Wu G, Ju L, Jin T, Chen L, Shao L, Wang Y, Liu B. Local delivery of recombinant human bone morphogenetic protein-2 increases axonal regeneration and the expression of tau protein after facial nerve injury. J Int Med Res 2011; 38:1682-8. [PMID: 21309482 DOI: 10.1177/147323001003800513] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
This study explored the function and possible mechanism of bone morphogenetic protein-2 (BMP-2) in the healing of injured peripheral nerves in vivo. Rabbit facial nerves were injured by clamping and then treated with recombinant human BMP-2 (rhBMP-2) or phosphate-buffered saline (control) by injecting once during surgery and twice a day post-injury for 7 days. Facial nerve fragments within 5 mm of the clamping point were examined at different times post-surgery. Axon structures visualized by Bielschowsky staining were similar in experimental and control nerves 2 and 6 weeks post-injury. At 4 weeks post-injury, cross-section images of facial nerves showed that axons treated with rhBMP-2 were denser and thicker, and levels of tau protein were increased. It is concluded from these data that rhBMP-2 may affect injured facial nerve regeneration by inducing more neurons to return to embryonic patterns of tau gene expression.
Collapse
Affiliation(s)
- G Wu
- School of Stomatology, The Fourth Military Medical University, Xi'an, China
| | | | | | | | | | | | | |
Collapse
|
4
|
Méchaly I, Bourane S, Piquemal D, Al-Jumaily M, Ventéo S, Puech S, Scamps F, Valmier J, Carroll P. Gene profiling during development and after a peripheral nerve traumatism reveals genes specifically induced by injury in dorsal root ganglia. Mol Cell Neurosci 2006; 32:217-29. [PMID: 16769221 DOI: 10.1016/j.mcn.2006.04.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2005] [Revised: 04/03/2006] [Accepted: 04/11/2006] [Indexed: 12/22/2022] Open
Abstract
In order to shed light on transcriptional networks involved in adult peripheral nerve repair program, we propose for the first time an organization of the transcriptional dynamics of the mouse dorsal root ganglia (DRG) following a sciatic nerve lesion. This was done by a non-hierarchical bioinformatical clustering of four Serial Analysis of Gene Expression libraries performed on DRG at embryonic day E13, neonatal day P0, adult and adult 3 days post-sciatic nerve section. Grouping genes according to their expression profiles shows that a combination of down-regulation of genes expressed at the adult stages, re-expression of embryonic genes and induction of a set of de novo genes takes place in injured neurons. Focusing on this latter event highlights Ddit3, Timm8b and Oazin as potential new injury-induced molecular actors involved in a stress response pathway. Their association with the traumatic state was confirmed by real-time PCR and in situ hybridization investigations. Clustering analysis allows us to distinguish developmental re-programming events from nerve-injury-induced processes and thus provides a basis for molecular understanding of transcriptional alterations taking place in the DRG after a sciatic nerve lesion.
Collapse
Affiliation(s)
- Ilana Méchaly
- I.N.S.E.R.M. U583, Institut des Neurosciences de Montpellier-Hôpital St Eloi. 80, rue Augustin Fliche. BP 74103. 34091 Montpellier cedex 5, France.
| | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Avila J, Lucas JJ, Perez M, Hernandez F. Role of tau protein in both physiological and pathological conditions. Physiol Rev 2004; 84:361-84. [PMID: 15044677 DOI: 10.1152/physrev.00024.2003] [Citation(s) in RCA: 639] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The morphology of a neuron is determined by its cytoskeletal scaffolding. Thus proteins that associate with the principal cytoskeletal components such as the microtubules have a strong influence on both the morphology and physiology of neurons. Tau is a microtubule-associated protein that stabilizes neuronal microtubules under normal physiological conditions. However, in certain pathological situations, tau protein may undergo modifications, mainly through phosphorylation, that can result in the generation of aberrant aggregates that are toxic to neurons. This process occurs in a number of neurological disorders collectively known as tauopathies, the most commonly recognized of which is Alzheimer's disease. The purpose of this review is to define the role of tau protein under normal physiological conditions and to highlight the role of the protein in different tauopathies.
Collapse
Affiliation(s)
- Jesus Avila
- Centro de Biología Molecular "Severo Ochoa", Facultad de Ciencias, Campus de Cantoblanco, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
| | | | | | | |
Collapse
|
6
|
Halverson RA, Chambers CB, Muma NA. Alternative splicing of amino-terminal Tau mRNA in rat spinal cord during development and following axonal injury. Exp Neurol 2001; 169:105-13. [PMID: 11312563 DOI: 10.1006/exnr.2001.7637] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tau is a family of microtubule-associated phosphoproteins in which isoform variation is produced by alternative splicing of a single gene and posttranslational modifications. Tau isoforms that include exon 10 are overexpressed in frontotemporal dementia and progressive supranuclear palsy. Therefore, we examined the expression of tau mRNA splice variants during axonal regeneration and abortive regeneration. Previous work in our laboratory demonstrated that expression of exon 10 tau isoforms during regeneration and abortive regeneration was altered and partially recapitulated the developmental patterns of tau isoform expression. Using RT-PCR, we examined the alternative splicing of exons 2 and 3 in tau during early postnatal development and regeneration in the rat spinal cord. The levels of tau lacking exons 2 and 3 were high on the day of birth and rapidly declined. Conversely, tau isoforms containing exon 2 or exons 2 and 3 first appeared at low levels and steadily increased. During axonal regeneration, the levels of all three tau mRNA isoforms were significantly lower 7 days after injury. In a model of abortive regeneration, all of the tau isoforms were elevated 14 and 42 days postinjury. The relative levels of exon 2 and 3 tau splice variants were not altered during regeneration or abortive regeneration as occurred during development. These results suggest that tau isoform expression following neuronal injury does not recapitulate the developmental pattern and is not independently regulated as in development. Our previous results together with these data suggest that alterations in tau mRNA isoform expression that occur in neurodegeneration are not secondary to axonal injury but may be a more primary event underlying cytoskeletal derangement.
Collapse
Affiliation(s)
- R A Halverson
- Department of Pharmacology, Loyola University Medical Center, 2160 South First Avenue, Maywood, Illinois, 60153, USA
| | | | | |
Collapse
|
7
|
Buée L, Bussière T, Buée-Scherrer V, Delacourte A, Hof PR. Tau protein isoforms, phosphorylation and role in neurodegenerative disorders. BRAIN RESEARCH. BRAIN RESEARCH REVIEWS 2000; 33:95-130. [PMID: 10967355 DOI: 10.1016/s0165-0173(00)00019-9] [Citation(s) in RCA: 1380] [Impact Index Per Article: 57.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Tau proteins belong to the family of microtubule-associated proteins. They are mainly expressed in neurons where they play an important role in the assembly of tubulin monomers into microtubules to constitute the neuronal microtubules network. Microtubules are involved in maintaining the cell shape and serve as tracks for axonal transport. Tau proteins also establish some links between microtubules and other cytoskeletal elements or proteins. Tau proteins are translated from a single gene located on chromosome 17. Their expression is developmentally regulated by an alternative splicing mechanism and six different isoforms exist in the human adult brain. Tau proteins are the major constituents of intraneuronal and glial fibrillar lesions described in Alzheimer's disease and numerous neurodegenerative disorders referred to as 'tauopathies'. Molecular analysis has revealed that an abnormal phosphorylation might be one of the important events in the process leading to their aggregation. Moreover, a specific set of pathological tau proteins exhibiting a typical biochemical pattern, and a different regional and laminar distribution could characterize each of these disorders. Finally, a direct correlation has been established between the progressive involvement of the neocortical areas and the increasing severity of dementia, suggesting that pathological tau proteins are reliable marker of the neurodegenerative process. The recent discovery of tau gene mutations in frontotemporal dementia with parkinsonism linked to chromosome 17 has reinforced the predominant role attributed to tau proteins in the pathogenesis of neurodegenerative disorders, and underlined the fact that distinct sets of tau isoforms expressed in different neuronal populations could lead to different pathologies.
Collapse
Affiliation(s)
- L Buée
- INSERM U422, Place de Verdun, 59045 cedex, Lille, France.
| | | | | | | | | |
Collapse
|
8
|
Mukaetova-Ladinska EB, Garcia-Siera F, Hurt J, Gertz HJ, Xuereb JH, Hills R, Brayne C, Huppert FA, Paykel ES, McGee M, Jakes R, Honer WG, Harrington CR, Wischik CM. Staging of cytoskeletal and beta-amyloid changes in human isocortex reveals biphasic synaptic protein response during progression of Alzheimer's disease. THE AMERICAN JOURNAL OF PATHOLOGY 2000; 157:623-36. [PMID: 10934165 PMCID: PMC1850134 DOI: 10.1016/s0002-9440(10)64573-7] [Citation(s) in RCA: 153] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/09/2000] [Indexed: 11/28/2022]
Abstract
We have examined the relationships between dementia, loss of synaptic proteins, changes in the cytoskeleton, and deposition of beta-amyloid plaques in the neocortex in a clinicopathologically staged epidemiological cohort using a combination of biochemical and morphometric techniques. We report that loss of synaptic proteins is a late-stage phenomenon, occurring only at Braak stages 5 and 6, or at moderate to severe clinical grades of dementia. Loss of synaptic proteins was seen only after the emergence of the full spectrum of tau and beta-amyloid pathology in the neocortex at stage 4, but not in the presence of beta-amyloid plaques alone. Contrary to previous studies, we report increases in the levels of synaptophysin, syntaxin, and SNAP-25 at stage 3 and of alpha-synuclein and MAP2 at stage 4. Minimal and mild clinical grades of dementia were associated with either unchanged or elevated levels of synaptic proteins in the neocortex. Progressive aggregation of paired helical filament (PHF)-tau protein could be detected biochemically from stage 2 onwards, and this was earliest change relative to the normal aging background defined by Braak stage 1 that we were able to detect in the neocortex. These results are consistent with the possibility that failure of axonal transport associated with early aggregation of tau protein elicits a transient adaptive synaptic response to partial de-afferentation that may be mediated by trophic factors. This early abnormality in cytoskeletal function may contribute directly to the earliest clinically detectable stages of dementia.
Collapse
|
9
|
Chambers CB, Muma NA. Tau mRNA isoforms following sciatic nerve axotomy with and without regeneration. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1997; 48:115-24. [PMID: 9379831 DOI: 10.1016/s0169-328x(97)00089-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The microtubule-associated protein tau promotes the polymerization and stabilization of microtubules in normal neurons and is the main component of paired helical filaments, one of the pathological structures characteristic of Alzheimer's disease (AD). In adult neurons alternative splicing generates tau isoforms with 4 microtubule binding domains (4R tau) while tau in developing neurons contains only 3 such domains (3R tau). The extra microtubule binding domain confers adult tau with an increased ability to interact with and stabilize microtubules. We hypothesized that tau gene expression would revert to the developmental pattern following nerve injury. The sciatic nerve of adult rats was unilaterally crushed or transected and tau mRNA isoform expression in the spinal cord was examined by reverse transcriptase-polymerase chain reaction. At 2 and 3 days post-crush, both the 3R and 4R tau mRNA isoform levels on the injured side had decreased compared to the contralateral side. However, the ratio of 4R to 3R tau mRNA was not significantly different between the two sides at any post-crush time point examined. Following nerve transection, a significant increase in the 3R tau mRNA isoform on the transected compared to the contralateral side occurred at 14 days; the ratio of 4R to 3R tau mRNA was significantly decreased on the transected compared to the contralateral side at 7, 14 and 42 days. These results suggest that a recapitulation of the developmental pattern of 3R tau gene expression occurs following nerve transection but not nerve crush. Our results combined with the recent findings that the 3R tau protein isoform preferentially forms paired helical filament-like structures in vitro suggests that an increased expression of the 3R tau mRNA isoform may also occur in AD.
Collapse
Affiliation(s)
- C B Chambers
- Department of Pharmacology, Loyola University Medical Center, Maywood, IL 60153, USA
| | | |
Collapse
|
10
|
Abstract
1. The developing spinal cords of bullfrogs and transected cords of stage IV tadpoles were subjected to two-dimensional gel electrophoresis and histological analysis. During development, the level of actin, alpha-tubulin or beta-tubulin in the 7-10th spinal segments increased with time and reached a maximum around stage XIII followed by a decrease, as shown from quantitative assay on protein spots of 2-dimensional gels of cord homogenates. In contrast, the level of 68 kD neurofilament subunit (NF68) was low in tadpoles but high in frog. 2. Following a complete transection made at the level of the 8th spinal segment, the cord tissue of the lesion zone degenerated; regeneration from each cut end then occurred, which lengthened for approximate 0.35 mm by 28 days after transection. The content of actin, alpha-tubulin and beta-tubulin in the cord within 1-2 mm of the transection site was elevated to 124-192% of control values 7-28 days post-transection, whereas NF68 declined to near non-detectable extent. 3. The regeneration of each cord stump included outgrowth of neuroepithelial cells and nerve fibers, reconstituting a newly regenerated cord segment. Ultrastructural examination revealed that features of the regrowth of fibers and guidance of neuroepithelial cells to the axonal growth resembled that seen in the developing cord. Thus the biochemical and morphological data support that the regeneration of the nervous system recaptulates its developmental events, providing evidence for molecular mechanism underlying central axonal regeneration.
Collapse
Affiliation(s)
- H S Yin
- Department of Anatomy, College of Medicine, National Taiwan University, Taipei, R.O.C
| |
Collapse
|
11
|
Yin HS, Mim MY. Distribution of non-phosphorylated and phosphorylated neurofilament proteins in the spinal cord of an anuran amphibian during development and regeneration. Exp Brain Res 1995; 104:409-18. [PMID: 7589293 DOI: 10.1007/bf00231976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The changes in the neurofilament medium and high molecular weight subunits (NF150 and NF200) in the developing and transected spinal cords of bullfrog tadpoles were studied. A monoclonal antibody recognizing the nonphosphorylated epitope of NF150, NF150D, stained the neuronal cell bodies and axons, whereas other antibodies against the phosphorylated NFs, NF150P or NF200P, labeled chiefly the axons. During development, the intensity of axonal staining by the anti-NF150D in the ventral fasciculi in younger tadpoles appeared stronger than older animals, but the reverse was seen for NF150P and NF200P. Complete signal transection of stage IV tadpoles resulted in degeneration and then regeneration of the cord tissue of both cut ends. Each stump lengthened by about 350 microns in the 4 weeks after the lesion. In the proximal stumps, the levels of NF150P or NF200P in the ventral axons at 550-350 microns proximal to the transection site increased notably by about 24-73% of the control value 7-28 days post-transection; however, the content of NF150D was decreased. The densities of NF150D and NF150P protein spots on the Coomassie blue-stained two-dimensional gels of the normal and injured cords also displayed alterations similar to the immunocytochemical data. Intense labeling by the anti-NF150P or NF200P was present in the cell bodies of axotomized motor neurons in the ventral horn. The results suggest that central axonal regeneration may be accompanied by upregulated phosphorylated neurofilament proteins.
Collapse
Affiliation(s)
- H S Yin
- Department of Anatomy, College of Medicine, National Taiwan University, Taipei, ROC
| | | |
Collapse
|