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Kang D. Advancing Fingertip Regeneration: Outcomes from a New Conservative Treatment Protocol. J Clin Med 2024; 13:3646. [PMID: 38999212 PMCID: PMC11242295 DOI: 10.3390/jcm13133646] [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: 05/13/2024] [Revised: 06/19/2024] [Accepted: 06/19/2024] [Indexed: 07/14/2024] Open
Abstract
Background Fingertip injuries with volar pulp tissue defects present a significant challenge in management. This study aimed to evaluate the efficacy of a conservative treatment protocol using artificial dermis and semi-occlusive dressings for these injuries. Methods A single-center, prospective study was conducted on 31 patients with fingertip injuries involving volar pulp defects. The treatment protocol included wound debridement, application of artificial dermis (Pelnac®), and a semi-occlusive dressing (IV3000®). The outcomes were assessed using subjective questionnaires and objective measures, including fingerprint regeneration, sensory function, pain, and cosmetic appearance. Results The mean treatment duration was 45.29 days (SD = 17.53). Complications were minimal, with only one case (3.22%) directly attributable to the treatment. Fingerprint regeneration was considerable (mean score = 2.58, SD = 0.67). The sensory disturbances were minimal, with no significant differences across injury types. Post-treatment pain was low (mean = 0.45, SD = 0.67), and cosmetic satisfaction was high (mean = 4.09, SD = 0.94). The overall patient satisfaction was high (mean = 4.41, SD = 0.67), regardless of injury severity. Conclusions The conservative treatment protocol using artificial dermis and semi-occlusive dressings is a promising strategy for managing fingertip injuries with volar pulp defects. This approach minimizes surgical morbidity and achieves excellent functional and aesthetic outcomes.
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Affiliation(s)
- Daihun Kang
- Department of Plastic and Reconstructive Surgery, Ewha Womans University Seoul Hospital, Seoul 03760, Republic of Korea
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2
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Amelogenin as a regenerative endodontic molecule for immature teeth with apical periodontitis. An experimental study. J Oral Biol Craniofac Res 2022; 12:721-726. [DOI: 10.1016/j.jobcr.2022.08.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 05/28/2022] [Accepted: 08/10/2022] [Indexed: 11/21/2022] Open
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Rezaei-Lotfi S, Vujovic F, Simonian M, Hunter N, Farahani RM. Programmed genomic instability regulates neural transdifferentiation of human brain microvascular pericytes. Genome Biol 2021; 22:334. [PMID: 34886891 PMCID: PMC8656028 DOI: 10.1186/s13059-021-02555-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 11/22/2021] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Transdifferentiation describes transformation in vivo of specialized cells from one lineage into another. While there is extensive literature on forced induction of lineage reprogramming in vitro, endogenous mechanisms that govern transdifferentiation remain largely unknown. The observation that human microvascular pericytes transdifferentiate into neurons provided an opportunity to explore the endogenous molecular basis for lineage reprogramming. RESULTS We show that abrupt destabilization of the higher-order chromatin topology that chaperones lineage memory of pericytes is driven by transient global transcriptional arrest. This leads within minutes to localized decompression of the repressed competing higher-order chromatin topology and expression of pro-neural genes. Transition to neural lineage is completed by probabilistic induction of R-loops in key myogenic loci upon re-initiation of RNA polymerase activity, leading to depletion of the myogenic transcriptome and emergence of the neurogenic transcriptome. CONCLUSIONS These findings suggest that the global transcriptional landscape not only shapes the functional cellular identity of pericytes, but also stabilizes lineage memory by silencing the competing neural program within a repressed chromatin state.
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Affiliation(s)
- Saba Rezaei-Lotfi
- IDR/Westmead Institute for Medical Research, Westmead, NSW 2145 Australia
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006 Australia
| | - Filip Vujovic
- IDR/Westmead Institute for Medical Research, Westmead, NSW 2145 Australia
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006 Australia
| | - Mary Simonian
- IDR/Westmead Institute for Medical Research, Westmead, NSW 2145 Australia
| | - Neil Hunter
- IDR/Westmead Institute for Medical Research, Westmead, NSW 2145 Australia
| | - Ramin M. Farahani
- IDR/Westmead Institute for Medical Research, Westmead, NSW 2145 Australia
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006 Australia
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4
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Byers MR, Calkins DF. Trigeminal sensory nerve patterns in dentine and their responses to attrition in rat molars. Arch Oral Biol 2021; 129:105197. [PMID: 34146928 DOI: 10.1016/j.archoralbio.2021.105197] [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: 02/07/2021] [Revised: 06/03/2021] [Accepted: 06/08/2021] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Our goal was to define trigeminal nerve ending quantities and patterns in rat molar dentine, their responses to attrition (tooth wear), and their associated odontoblasts and connections with pulpal plexuses. DESIGN Trigeminal ganglia were labeled for axonal transport of 3H-proteins to dentinal nerve endings in male rats (3-13 months old). Autoradiography detected radio-labeled dentinal tubules as indicators of nerve ending locations. Quantitative morphometry was done (ANOVA, t-tests), and littermates were compared for attrition and innervation. RESULTS There were six dentinal patterns, only two of which had an associated neural plexus of Raschkow and cell-free zone (Den-1, Den-2). Other nerves entered dentin from bush-like endings near elongated odontoblasts (Den-B), as single fibers (Den-X), as networks in predentine (PdN), or as single fibers in tertiary dentine at cusp tips (Den-S). There were at least 186,600 innervated dentinal tubules within the set of three right maxillary molars of the best-labeled rat, and similar densities were found in other rats. Attrition levels differed among cusps and in littermates (t-test p < 0.02-0.0001), but the matched right/left cusps per rat were similar. Innervations of tertiary and enamel-free dentine (Den-S, Den-X) were preserved in all rats. Den-B and Den-2 coronal patterns were unchanged unless displaced by dentinogenesis. Den-1 losses occurred in older cusps, while Den-2 patterns increased near cervical and intercuspal odontoblasts. CONCLUSIONS The extensive molar dentinal innervation had unique distributions per rat per cusp that depended on region (buccal, middle, palatal) and attrition, but only two of six patterns connected to a plexus of Raschkow.
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Affiliation(s)
- Margaret R Byers
- Department of Anesthesiology and Pain Medicine, Univ. Washington, Seattle, WA, 98195-6540, USA.
| | - Dianne F Calkins
- Department of Anesthesiology and Pain Medicine, Univ. Washington, Seattle, WA, 98195-6540, USA
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5
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Mounir MMF, Rashed FM, Bukhary SM. Regeneration of Neural Networks in Immature Teeth with Non-Vital Pulp Following a Novel Regenerative Procedure. Int J Stem Cells 2019; 12:410-418. [PMID: 31658509 PMCID: PMC6881045 DOI: 10.15283/ijsc19026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 07/17/2019] [Accepted: 08/22/2019] [Indexed: 11/24/2022] Open
Abstract
Background and Objectives Recombinant amelogenin protein (RAP) was reported to induce soft-tissue regeneration in canine infected endodontically treated permanent teeth with open apices. To characterize identities of the cells found in the RAP regenerated tissues compared to authentic pulp by identifying: 1) stem cells by their expression of Sox2; 2) nerve fibers by distribution of the axonal marker peripherin; 3) axons by their expression of calcitonin gene–related peptide (CGRP); 4) the presence of astrocytes expressing glial fibrillary acidic proteins (GFAP). Methods A total of 240 open-apex root canals in dogs were used. After establishment of oral contamination to the pulp, the canals were cleaned, irrigated, and 120 canals filled with RAP, and the other 120 with calcium hydroxide. Results After 1, 3, and 6 months, teeth were recovered for immune-detection of protein markers associated with native pulp tissues. Regenerated pulp and apical papilla of RAP group revealed an abundance of stem cells showing intense immunoreactivity to Sox2 antibody, immunoreactivity of peripherin mainly in the A-fibers of the odontoblast layer and immunoreactivity to CGRP fibers in the central pulp region indicative of C-fibres. GFAP immunoreactivity was observed near the odontoblastic, cell-rich regions and throughout the regenerated pulp. Conclusions RAP induces pulp regeneration following regenerative endodontic procedures with cells identity by gene expression demonstrating a distribution pattern similar to the authentic pulp innervation. A- and C-fibers, as well as GFAP specific to astrocytic differentiation, are recognized. The origin of the regenerated neural networks may be derived from the Sox2 identified stem cells within the apical papilla.
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Affiliation(s)
- Maha M F Mounir
- Department of Oral Diagnostic Sciences, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia.,Faculty of Dentistry, Alexandria University, Alexadria, Egypt
| | - Fatma M Rashed
- Department of Oral Biology, Faculty of Dentistry, Damanhour University, Damanhour, Egypt
| | - Sahar M Bukhary
- Department of Oral Biology, King Abdulaziz University, Faculty of Dentistry, Jeddah, Saudi Arabia
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6
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Vijaykumar A, Ghassem-Zadeh S, Vidovic-Zdrilic I, Komitas K, Adameyko I, Krivanek J, Fu Y, Maye P, Mina M. Generation and characterization of DSPP-Cerulean/DMP1-Cherry reporter mice. Genesis 2019; 57:e23324. [PMID: 31271259 PMCID: PMC6939995 DOI: 10.1002/dvg.23324] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 06/13/2019] [Accepted: 06/14/2019] [Indexed: 12/24/2022]
Abstract
To gain a better understanding of the progression of progenitor cells in the odontoblast lineage, we have examined and characterized the expression of a series of GFP reporters during odontoblast differentiation. However, previously reported GFP reporters (pOBCol2.3-GFP, pOBCol3.6-GFP, and DMP1-GFP), similar to the endogenous proteins, are also expressed by bone-forming cells, which made it difficult to delineate the two cell types in various in vivo and in vitro studies. To overcome these difficulties we generated DSPP-Cerulean/DMP1-Cherry transgenic mice using a bacterial recombination strategy with the mouse BAC clone RP24-258g7. We have analyzed the temporal and spatial expression of both transgenes in tooth and bone in vivo and in vitro. This transgenic animal enabled us to visualize the interactions between odontoblasts and surrounding tissues including dental pulp, ameloblasts and cementoblasts. Our studies showed that DMP1-Cherry, similar to Dmp1, was expressed in functional and fully differentiated odontoblasts as well as osteoblasts, osteocytes and cementoblasts. Expression of DSPP-Cerulean transgene was limited to functional and fully differentiated odontoblasts and correlated with the expression of Dspp. This transgenic animal can help in the identification and isolation of odontoblasts at later stages of differentiation and help in better understanding of developmental disorders in dentin and odontoblasts.
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Affiliation(s)
- Anushree Vijaykumar
- Department of Craniofacial Sciences School of Dental Medicine, University of Connecticut, Farmington, Connecticut
| | - Sean Ghassem-Zadeh
- Department of Craniofacial Sciences School of Dental Medicine, University of Connecticut, Farmington, Connecticut
| | - Ivana Vidovic-Zdrilic
- Department of Craniofacial Sciences School of Dental Medicine, University of Connecticut, Farmington, Connecticut
| | - Karren Komitas
- Department of Craniofacial Sciences School of Dental Medicine, University of Connecticut, Farmington, Connecticut
| | - Igor Adameyko
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Jan Krivanek
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Yu Fu
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut, Farmington, Connecticut
| | - Peter Maye
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut, Farmington, Connecticut
| | - Mina Mina
- Department of Craniofacial Sciences School of Dental Medicine, University of Connecticut, Farmington, Connecticut
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7
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Byers MR. Chewing causes rapid changes in immunoreactive nerve patterns in rat molar teeth: Implications for dental proprioception and pain. Arch Oral Biol 2019; 107:104511. [PMID: 31445382 DOI: 10.1016/j.archoralbio.2019.104511] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 07/19/2019] [Accepted: 07/28/2019] [Indexed: 01/06/2023]
Abstract
OBJECTIVE This study tests the hypothesis that normal use of teeth (chewing) causes changes in immunoreactive-(IR) patterns for endings of large Aβ and CGRP axons in rat molar cusps. DESIGN First, a new paradigm to test chewing in adult male rats was developed. Then IR patterns for large dental axons were analysed for a calcium-binding protein, parvalbumin (PV), heavy neurofilament protein-200 (NFP), and vesicle-release molecule synaptophysin (SYN) that all typify large dental axons and proprioceptors for comparison with endings of CGRP-IR neuropeptide axons. The behavior groups were: (1) daytime sleeping/fasting (Group:SF); (2) brief feeding after 8-11 h of daytime sleeping/fasting (Group:SF-C); (3) normal nocturnal feeding (Group:N); (4) nocturnal fasting (Group:NF); (5) brief feeding/chewing after nocturnal fasting (Group:NF-C). RESULTS Nerve endings with NFP-, PV-, or SYN-IR were lost or altered in pulp and dentin in all chewing groups. Other endings with CGRP-IR were near those with PV-, NFP- and SYN-IR at the pulp-dentin border and in dentin, and they also lost immunoreactivity in all chewing groups. The special beaded regions along the crown pulp/dentin borders lost neural labeling in all chewing groups. Nerves of molar roots and periodontal ligament were not changed. CONCLUSIONS Rapid neural reactions to chewing show extensive, reversible, non-nociceptive depletions of crown innervation. Those changes were rapid enough to occur during normal feeding followed by recovery during rest. The new dental paradigm related to chewing and fasting allows dissection of intradental proprioceptive-like mechanisms during normal tooth functions for comparison with nociceptive and mechanosensitive reactions after injury or inflammation.
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Affiliation(s)
- Margaret R Byers
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA, 98195-6540 USA.
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8
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Farahani RM, Rezaei-Lotfi S, Simonian M, Xaymardan M, Hunter N. Neural microvascular pericytes contribute to human adult neurogenesis. J Comp Neurol 2018; 527:780-796. [PMID: 30471080 DOI: 10.1002/cne.24565] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 10/06/2018] [Accepted: 10/17/2018] [Indexed: 12/17/2022]
Abstract
Consistent adult neurogenic activity in humans is observed in specific niches within the central nervous system. However, the notion of an adult neurogenic niche is challenged by accumulating evidence for ectopic neurogenic activity in other cerebral locations. Herein we interface precision of ultrastructural resolution and anatomical simplicity of accessible human dental pulp neurogenic zone to address this conflict. We disclose a basal level of adult neurogenic activity characterized by glial invasion of terminal microvasculature followed by release of individual platelet-derived growth factor receptor-β mural pericytes and subsequent reprogramming into NeuN+ local interneurons. Concomitant angiogenesis, a signature of adult neurogenic niches, accelerates the rate of neurogenesis by amplifying release and proliferation of the mural pericyte population by ≈10-fold. Subsequent in vitro and in vivo experiments confirmed gliogenic and neurogenic capacities of human neural pericytes. Findings foreshadow the bimodal nature of the glio-vascular assembly where pericytes, under instruction from glial cells, can stabilize the quiescent microvasculature or enrich local neuronal microcircuits upon differentiation.
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Affiliation(s)
- Ramin M Farahani
- Institute of Dental Research, Westmead Institute for Medical Research and Westmead Centre for Oral Health, Westmead, New South Wales, Australia.,Department of Life Sciences, Faculty of Medicine and Health Sciences, University of Sydney, Camperdown, New South Wales, Australia
| | - Saba Rezaei-Lotfi
- Department of Life Sciences, Faculty of Medicine and Health Sciences, University of Sydney, Camperdown, New South Wales, Australia
| | - Mary Simonian
- Institute of Dental Research, Westmead Institute for Medical Research and Westmead Centre for Oral Health, Westmead, New South Wales, Australia
| | - Munira Xaymardan
- Institute of Dental Research, Westmead Institute for Medical Research and Westmead Centre for Oral Health, Westmead, New South Wales, Australia.,Department of Life Sciences, Faculty of Medicine and Health Sciences, University of Sydney, Camperdown, New South Wales, Australia
| | - Neil Hunter
- Institute of Dental Research, Westmead Institute for Medical Research and Westmead Centre for Oral Health, Westmead, New South Wales, Australia.,Department of Life Sciences, Faculty of Medicine and Health Sciences, University of Sydney, Camperdown, New South Wales, Australia
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9
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Couve E, Schmachtenberg O. Schwann Cell Responses and Plasticity in Different Dental Pulp Scenarios. Front Cell Neurosci 2018; 12:299. [PMID: 30233330 PMCID: PMC6133954 DOI: 10.3389/fncel.2018.00299] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2018] [Accepted: 08/17/2018] [Indexed: 12/29/2022] Open
Abstract
Mammalian teeth have evolved as dentin units that enclose a complex system of sensory innervation to protect and preserve their structure and function. In human dental pulp (DP), mechanosensory and nociceptive fibers form a dense meshwork of nerve endings at the coronal dentin-pulp interface, which arise from myelinated and non-myelinated axons of the Raschkow plexus (RP). Schwann cells (SCs) play a crucial role in the support, maintenance and regeneration after injury of these fibers. We have recently characterized two SC phenotypes hierarchically organized within the coronal and radicular DP in human teeth. Myelinating and non-myelinating SCs (nmSCs) display a high degree of plasticity associated with nociceptive C-fiber sprouting and axonal degeneration in response to DP injuries from dentin caries or physiological root resorption (PRR). By comparative immunolabeling, confocal and electron microscopy, we have characterized short-term adaptive responses of SC phenotypes to nerve injuries, and long-term changes related to aging. An increase of SCs characterizes the early responses to caries progression in association with axonal sprouting in affected DP domains. Moreover, during PRR, the formation of bands of Büngner is observed as part of SC repair tracks functions. On the other hand, myelinated axon density is significantly reduced with tooth age, as part of a gradual decrease in DP defense and repair capacities. The remarkable plasticity and capacity of SCs to preserve DP innervation in different dental scenarios constitutes a fundamental aspect to improve clinical treatments. This review article discusses the central role of myelinating and non-mSCs in long-term tooth preservation and homeostasis.
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Affiliation(s)
- Eduardo Couve
- Laboratorio de Microscopía Electrónica, Instituto de Biología, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Oliver Schmachtenberg
- Centro Interdisciplinario de Neurociencias de Valparaíso (CINV), Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
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10
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Couve E, Lovera M, Suzuki K, Schmachtenberg O. Schwann Cell Phenotype Changes in Aging Human Dental Pulp. J Dent Res 2017; 97:347-355. [PMID: 28972819 DOI: 10.1177/0022034517733967] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Schwann cells are glial cells that support axonal development, maintenance, defense, and regeneration in the peripheral nervous system. There is limited knowledge regarding the organization, plasticity, and aging of Schwann cells within the dental pulp in adult permanent teeth. The present study sought to relate changes in the pattern of Schwann cell phenotypes between young and old adult teeth with neuronal, immune, and vascular components of the dental pulp. Schwann cells are shown to form a prominent glial network at the dentin-pulp interface, consisting of nonmyelinating and myelinating phenotypes, forming a multicellular neuroimmune interface in association with nerve fibers and dendritic cells. Schwann cell phenotypes are recognized by the expression of S100, glial fibrillary acidic protein (GFAP), myelin basic protein (MBP), Sox10, GAP43, and p75NTR markers. In young adult teeth, a dense population of nonmyelinating Schwann cells projects processes in close association with sensory nerve terminals through the odontoblast layer, reaching the adjacent predentin/dentin domain. While GAP43 and p75NTR are highly expressed in nonmyelinating Schwann cells from young adult teeth, the presence of these markers declines significantly in old adult teeth. Myelinated axons, identified by MBP expression, are mainly present at the Raschkow plexus and within nerve bundles in the dental pulp, but their density is significantly reduced in old adult versus young adult teeth. These data reveal age-related changes within the glial network of the dental pulp, in association with a reduction of coronal dental pulp innervation in old adult versus young adult teeth. The prominence of Schwann cells as a cellular component at the dentin-pulp interface supports the notion that their association with sensory nerve terminals and immune system components forms part of an integrated multicellular barrier for defense against pathogens and dentin repair.
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Affiliation(s)
- E Couve
- 1 Instituto de Biología, Laboratorio de Microscopía Electrónica, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - M Lovera
- 1 Instituto de Biología, Laboratorio de Microscopía Electrónica, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - K Suzuki
- 1 Instituto de Biología, Laboratorio de Microscopía Electrónica, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - O Schmachtenberg
- 2 Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
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Byers MR, Cornel LM. Multiple complex somatosensory systems in mature rat molars defined by immunohistochemistry. Arch Oral Biol 2017; 85:84-97. [PMID: 29035722 DOI: 10.1016/j.archoralbio.2017.09.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 08/24/2017] [Accepted: 09/13/2017] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Intradental sensory receptors trigger painful sensations and unperceived mechanosensitivity, but the receptor bases for those functions are only partly defined. We present new evidence here concerning complex endings of myelinated axons in rat molars. DESIGN We sectioned mature rat jaws in sagittal and transverse planes to analyze neural immunoreactivity (IR) for parvalbumin, peripherin, neurofilament protein, neurotrophin receptors, synaptophysin, calcitonin gene-related peptide (CGRP), or mas-related g-protein-receptor-d (Mrgprd). RESULTS We found two complex sensory systems in mature rat molar dentin that labeled with neurofilament protein-IR, plus either parvalbumin-IR or peripherin-IR. The parvalbumin-IR system made extensively branched, beaded endings focused into dentin throughout each pulp horn. The peripherin-IR system primarily made unbeaded, fork-shaped dentinal endings scattered throughout crown including cervical regions. Both of these systems differed from neuropeptide CGRP-IR. In molar pulp we found peripherin- and parvalbumin-IR layered endings, either near special horizontal plexus arrays or in small coiled endings near tangled plexus, each with specific foci for specific pulp horns. Parvalbumin-IR nerve fibers had Aβ axons (5-7μm diameter), while peripherin-IR axons were thinner Aδ size (2-5μm). Mechano-nociceptive Mrgprd-IR was only found in peripherin-IR axons. CONCLUSIONS Complex somatosensory receptors in rat molars include two types of dentinal endings that both differ from CGRP-IR endings, and at least two newly defined types of pulpal endings. The PV-IR neurons with their widely branched, synaptophysin-rich, intradentinal beaded endings are good candidates for endodontic non-nociceptive, low threshold, unperceived mechanoreceptors. The complex molar dentinal and pulpal sensory systems were not found in rat incisors.
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Affiliation(s)
- Margaret R Byers
- Department of Anesthesiology & Pain Medicine, Box 356540, University of Washington, Seattle, WA 98195-6540, USA.
| | - Leanne M Cornel
- Department of Anesthesiology & Pain Medicine, Box 356540, University of Washington, Seattle, WA 98195-6540, USA
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12
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Morishita H, Arora M. Tooth-Matrix Biomarkers to Reconstruct Critical Periods of Brain Plasticity. Trends Neurosci 2016; 40:1-3. [PMID: 28038829 DOI: 10.1016/j.tins.2016.11.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 11/18/2016] [Indexed: 12/11/2022]
Abstract
Developmental brain plasticity involves complex, time-dependent dynamic molecular interactions that cannot be observed directly in humans. We propose that the shared evolutionary homology of teeth and the neurosensory system, and the archival nature of dentine microstructure, allows the development of 'biologic hard drives' that can characterize perinatal temporal dynamics in neuroplasticity.
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Affiliation(s)
- Hirofumi Morishita
- Department of Psychiatry, Neuroscience, and Ophthalmology, Friedman Brain Institute, Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| | - Manish Arora
- Division of Environmental Health, Department of Environmental Medicine and Public Health, Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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13
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Sundar R, Jeyasekharan AD, Pang B, Soong RCT, Kumarakulasinghe NB, Ow SGW, Ho J, Lim JSJ, Tan DSP, Wilder-Smith EPV, Bandla A, Tan SSH, Asuncion BR, Fazreen Z, Hoppe MM, Putti TC, Poh LM, Goh BC, Lee SC. Low Levels of NDRG1 in Nerve Tissue Are Predictive of Severe Paclitaxel-Induced Neuropathy. PLoS One 2016; 11:e0164319. [PMID: 27716814 PMCID: PMC5055363 DOI: 10.1371/journal.pone.0164319] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 09/22/2016] [Indexed: 11/23/2022] Open
Abstract
Introduction Sensory peripheral neuropathy caused by paclitaxel is a common and dose limiting toxicity, for which there are currently no validated predictive biomarkers. We investigated the relationship between the Charcot-Marie-Tooth protein NDRG1 and paclitaxel-induced neuropathy. Methods/Materials Archived mammary tissue specimen blocks of breast cancer patients who received weekly paclitaxel in a single centre were retrieved and NDRG1 immunohistochemistry was performed on normal nerve tissue found within the sample. The mean nerve NDRG1 score was defined by an algorithm based on intensity of staining and percentage of stained nerve bundles. NDRG1 scores were correlated with paclitaxel induced neuropathy Results 111 patients were studied. 17 of 111 (15%) developed severe paclitaxel-induced neuropathy. The mean nerve NDRG1 expression score was 5.4 in patients with severe neuropathy versus 7.7 in those without severe neuropathy (p = 0.0019). A Receiver operating characteristic (ROC) curve analysis of the mean nerve NDRG1 score revealed an area under the curve of 0.74 (p = 0.0013) for the identification of severe neuropathy, with a score of 7 being most discriminative. 13/54 (24%) subjects with an NDRG1 score < = 7 developed severe neuropathy, compared to only 4/57 (7%) in those with a score >7 (p = 0.017). Conclusion Low NDRG1 expression in nerve tissue present within samples of surgical resection may identify subjects at risk for severe paclitaxel-induced neuropathy. Since nerve biopsies are not routinely feasible for patients undergoing chemotherapy for early breast cancer, this promising biomarker strategy is compatible with current clinical workflow.
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Affiliation(s)
- Raghav Sundar
- Department of Haematology-Oncology, National University Cancer Institute, Singapore, National University Health System, Singapore, Singapore
| | - Anand D. Jeyasekharan
- Department of Haematology-Oncology, National University Cancer Institute, Singapore, National University Health System, Singapore, Singapore
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Brendan Pang
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
- Department of Pathology, National University Health System, Singapore, Singapore
| | - Richie Chuan Teck Soong
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
- Department of Pathology, National University Health System, Singapore, Singapore
| | - Nesaretnam Barr Kumarakulasinghe
- Department of Haematology-Oncology, National University Cancer Institute, Singapore, National University Health System, Singapore, Singapore
| | - Samuel Guan Wei Ow
- Department of Haematology-Oncology, National University Cancer Institute, Singapore, National University Health System, Singapore, Singapore
| | - Jingshan Ho
- Department of Haematology-Oncology, National University Cancer Institute, Singapore, National University Health System, Singapore, Singapore
| | - Joline Si Jing Lim
- Department of Haematology-Oncology, National University Cancer Institute, Singapore, National University Health System, Singapore, Singapore
| | - David Shao Peng Tan
- Department of Haematology-Oncology, National University Cancer Institute, Singapore, National University Health System, Singapore, Singapore
| | - Einar P. V. Wilder-Smith
- Singapore Institute for Neurotechnology (SINAPSE), National University of Singapore, Singapore, Singapore
- Department of Medicine, National University Health System, Singapore, Singapore
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Aishwarya Bandla
- Singapore Institute for Neurotechnology (SINAPSE), National University of Singapore, Singapore, Singapore
- Department of Biomedical Engineering, National University of Singapore, Singapore, Singapore
| | - Stacey Sze Hui Tan
- Singapore Institute for Neurotechnology (SINAPSE), National University of Singapore, Singapore, Singapore
| | | | - Zul Fazreen
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Michal Marek Hoppe
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | | | - Lay Mui Poh
- Department of Pharmacy, National University Cancer Institute Singapore, National University Health System, Singapore, Singapore
| | - Boon Cher Goh
- Department of Haematology-Oncology, National University Cancer Institute, Singapore, National University Health System, Singapore, Singapore
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Soo-Chin Lee
- Department of Haematology-Oncology, National University Cancer Institute, Singapore, National University Health System, Singapore, Singapore
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
- * E-mail:
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14
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Kim SH, Kim S, Shin Y, Lee HS, Jeon M, Kim SO, Cho SW, Ruparel NB, Song JS. Comparative Gene Expression Analysis of the Coronal Pulp and Apical Pulp Complex in Human Immature Teeth. J Endod 2016; 42:752-9. [DOI: 10.1016/j.joen.2016.01.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2015] [Revised: 01/24/2016] [Accepted: 01/30/2016] [Indexed: 12/20/2022]
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15
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Hunter DJ, Bardet C, Mouraret S, Liu B, Singh G, Sadoine J, Dhamdhere G, Smith A, Tran XV, Joy A, Rooker S, Suzuki S, Vuorinen A, Miettinen S, Chaussain C, Helms JA. Wnt Acts as a Prosurvival Signal to Enhance Dentin Regeneration. J Bone Miner Res 2015; 30:1150-9. [PMID: 25556760 DOI: 10.1002/jbmr.2444] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 12/11/2014] [Accepted: 12/23/2014] [Indexed: 01/08/2023]
Abstract
Wnt proteins are lipid-modified, short-range signals that control stem cell self-renewal and tissue regeneration. We identified a population of Wnt responsive cells in the pulp cavity, characterized their function, and then created a pulp injury. The repair response was evaluated over time using molecular, cellular, and quantitative assays. We tested how healing was impacted by wound environments in which Wnt signaling was amplified. We found that a Wnt-amplified environment was associated with superior pulp healing. Although cell death was still rampant, the number of cells undergoing apoptosis was significantly reduced. This resulted in significantly better survival of injured pulp cells, and resulted in the formation of more tertiary dentin. We engineered a liposome-reconstituted form of WNT3A then tested whether this biomimetic compound could activate cells in the injured tooth pulp and stimulate dentin regeneration. Pulp cells responded to the elevated Wnt stimulus by differentiating into secretory odontoblasts. Thus, transiently amplifying the body's natural Wnt response resulted in improved pulp vitality. These data have direct clinical implications for treating dental caries, the most prevalent disease affecting mankind.
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Affiliation(s)
- Daniel J Hunter
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA
| | - Claire Bardet
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA.,EA 2496, Dental School, University Paris Descartes, Sorbonne Paris Cité, Montrouge, France
| | - Sylvain Mouraret
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA.,Department of Periodontology, Service of Odontology, Rothschild Hospital, Assistance Publique-Hôpitaux de Paris, Paris 7, Université Paris Diderot, Unité de Formation et de Recherche (UFR) of Odontology, Paris, France
| | - Bo Liu
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA
| | - Gurpreet Singh
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA
| | - Jérémy Sadoine
- EA 2496, Dental School, University Paris Descartes, Sorbonne Paris Cité, Montrouge, France
| | - Girija Dhamdhere
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA
| | - Andrew Smith
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA.,Department of Biological Sciences, San Jose State University, San Jose, CA, USA
| | - Xuan Vinh Tran
- EA 2496, Dental School, University Paris Descartes, Sorbonne Paris Cité, Montrouge, France
| | - Adrienne Joy
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA
| | - Scott Rooker
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA
| | - Shigeki Suzuki
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA.,Department of Dental Science for Health Promotion, Division of Cervico-Gnathostomatology Hiroshima, University Graduate School of Biomedical Sciences, Hiroshima, Japan
| | - Annukka Vuorinen
- BioMediTech, Adult Stem Cell Research, University of Tampere, Tampere, Finland.,Finnish Student Health Service, Tampere, Finland
| | - Susanna Miettinen
- BioMediTech, Adult Stem Cell Research, University of Tampere, Tampere, Finland.,Science Centre, University of Tampere, Tampere, Finland
| | - Catherine Chaussain
- EA 2496, Dental School, University Paris Descartes, Sorbonne Paris Cité, Montrouge, France
| | - Jill A Helms
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford, CA, USA
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16
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Khatibi Shahidi M, Krivanek J, Kaukua N, Ernfors P, Hladik L, Kostal V, Masich S, Hampl A, Chubanov V, Gudermann T, Romanov R, Harkany T, Adameyko I, Fried K. Three-dimensional Imaging Reveals New Compartments and Structural Adaptations in Odontoblasts. J Dent Res 2015; 94:945-54. [DOI: 10.1177/0022034515580796] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
In organized tissues, the precise geometry and the overall shape are critical for the specialized functions that the cells carry out. Odontoblasts are major matrix-producing cells of the tooth and have also been suggested to participate in sensory transmission. However, refined morphologic data on these important cells are limited, which hampers the analysis and understanding of their cellular functions. We took advantage of fluorescent color-coding genetic tracing to visualize and reconstruct in 3 dimensions single odontoblasts, pulp cells, and their assemblages. Our results show distinct structural features and compartments of odontoblasts at different stages of maturation, with regard to overall cellular shape, formation of the main process, orientation, and matrix deposition. We demonstrate previously unanticipated contacts between the processes of pulp cells and odontoblasts. All reported data are related to mouse incisor tooth. We also show that odontoblasts express TRPM5 and Piezo2 ion channels. Piezo2 is expressed ubiquitously, while TRPM5 is asymmetrically distributed with distinct localization to regions proximal to and within odontoblast processes.
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Affiliation(s)
| | - J. Krivanek
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - N. Kaukua
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - P. Ernfors
- Unit of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - L. Hladik
- TESCAN ORSAY Holding, Brno, Czech Republic
| | - V. Kostal
- TESCAN ORSAY Holding, Brno, Czech Republic
| | - S. Masich
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - A. Hampl
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - V. Chubanov
- Ludwig-Maximilians-Universität München, Walther-Straub-Institut für Pharmakologie und Toxikologie, München, Germany
| | - T. Gudermann
- Ludwig-Maximilians-Universität München, Walther-Straub-Institut für Pharmakologie und Toxikologie, München, Germany
| | - R.A. Romanov
- Unit of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - T. Harkany
- Unit of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Department of Molecular Neurosciences, Center of Brain Research, Medical University of Vienna, Vienna, Austria
| | - I. Adameyko
- Department of Molecular Neurosciences, Center of Brain Research, Medical University of Vienna, Vienna, Austria
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - K. Fried
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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17
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Chow CL, Guo W, Trivedi P, Zhao X, Gubbels SP. Characterization of a unique cell population marked by transgene expression in the adult cochlea of nestin-CreER(T2)/tdTomato-reporter mice. J Comp Neurol 2015; 523:1474-87. [PMID: 25611038 DOI: 10.1002/cne.23747] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 10/18/2014] [Accepted: 01/13/2015] [Indexed: 02/06/2023]
Abstract
Hair cells in the adult mammalian cochlea cannot spontaneously regenerate after damage, resulting in the permanency of hearing loss. Stem cells have been found to be present in the cochlea of young rodents; however, there has been little evidence for their existence into adulthood. We used nestin-CreER(T2)/tdTomato-reporter mice to trace the lineage of putative nestin-expressing cells and their progeny in the cochleae of adult mice. Nestin, an intermediate filament found in neural progenitor cells during early development and adulthood, is regarded as a multipotent and neural stem cell marker. Other investigators have reported its presence in postnatal and young adult rodents; however, there are discrepancies among these reports. Using lineage tracing, we documented a robust population of tdTomato-expressing cells and evaluated these cells at a series of adult time points. Upon activation of the nestin promoter, tdTomato was observed just below and medial to the inner hair cell layer. All cells colocalized with the stem cell and cochlear-supporting-cell marker Sox2 as well as the supporting cell and Schwann cell marker Sox10; however, they did not colocalize with the Schwann cell marker Krox20, spiral ganglion marker NF200, nor glial fibrillary acidic acid (GFAP)-expressing supporting cell marker. The cellular identity of this unique population of tdTomato-expressing cells in the adult cochlea of nestin-CreER(T2)/tdTomato mice remains unclear; however, these cells may represent a type of supporting cell on the neural aspect of the inner hair cell layer.
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Affiliation(s)
- Cynthia L Chow
- Department of Communication Sciences and Disorders, University of Wisconsin-Madison, Madison, Wisconsin, 53706.,Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, 53705
| | - Weixiang Guo
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, 53705
| | - Parul Trivedi
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, 53705
| | - Xinyu Zhao
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, 53705.,Department of Neuroscience, University of Wisconsin-Madison, Madison, Wisconsin, 53706
| | - Samuel P Gubbels
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, 53705.,Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of Wisconsin-Madison, Madison, Wisconsin, 53792
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18
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Chen H, Iinuma M, Onozuka M, Kubo KY. Chewing Maintains Hippocampus-Dependent Cognitive Function. Int J Med Sci 2015; 12:502-9. [PMID: 26078711 PMCID: PMC4466515 DOI: 10.7150/ijms.11911] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 05/25/2015] [Indexed: 02/07/2023] Open
Abstract
Mastication (chewing) is important not only for food intake, but also for preserving and promoting the general health. Recent studies have showed that mastication helps to maintain cognitive functions in the hippocampus, a central nervous system region vital for spatial memory and learning. The purpose of this paper is to review the recent progress of the association between mastication and the hippocampus-dependent cognitive function. There are multiple neural circuits connecting the masticatory organs and the hippocampus. Both animal and human studies indicated that cognitive functioning is influenced by mastication. Masticatory dysfunction is associated with the hippocampal morphological impairments and the hippocampus-dependent spatial memory deficits, especially in elderly. Mastication is an effective behavior for maintaining the hippocampus-dependent cognitive performance, which deteriorates with aging. Therefore, chewing may represent a useful approach in preserving and promoting the hippocampus-dependent cognitive function in older people. We also discussed several possible mechanisms involved in the interaction between mastication and the hippocampal neurogenesis and the future directions for this unique fascinating research.
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Affiliation(s)
- Huayue Chen
- 1. Department of Anatomy Gifu University Graduate School of Medicine, Gifu, 501-1194, Gifu, Japan
| | - Mitsuo Iinuma
- 2. Department of Pediatric Dentistry, Division of Oral Structure, Function and Development, Asahi University, School of Dentistry, Mizuho, 501-0296, Gifu, Japan
| | - Minoru Onozuka
- 3. Department of Judo Therapy and Medical Science, Faculty of Medical Science, Nippon Sport Science University, Yokohama 227-0033, Kanagawa, Japan
| | - Kin-Ya Kubo
- 4. Seijoh University Graduate School of Health Care Studies, Tokai, 476-8588, Aichi, Japan
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19
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Daud S, Nambiar P, Hossain MZ, Rahman MRA, Bakri MM. Changes in cell density and morphology of selected cells of the ageing human dental pulp. Gerodontology 2014; 33:315-21. [PMID: 25266855 DOI: 10.1111/ger.12154] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2014] [Indexed: 11/27/2022]
Abstract
OBJECTIVES The aim of this study was to determine the changes in cell density and morphology of selected cells of the ageing human dental pulp. BACKGROUND Changes in cell density and morphology of dental pulp cells over time may affect their capability to respond to tooth injury. MATERIALS AND METHODS One hundred thirty-one extracted teeth were obtained from individuals between the ages of 6 and 80 years. The apical 1/3 of the root region was removed from all teeth prior to routine processing for producing histological slides. The histology slides were used to study the changes in cell density and morphology of selected pulp cells; odontoblasts, subodontoblasts and fibroblasts in the crown and root regions of the dental pulp. Student's t-test and one-way anova were used for statistical analyses. RESULTS In all age groups, the cell density for all types of cells was found to be higher in the crown than in the root (p < 0.05). In general, the pulp cell density was found to decrease with age in both the crown and root regions. However, it was noted that the reduction of coronal odontoblasts occurred later in life (40-49 years) when compared to that of subodontoblasts or fibroblasts (30-39 years). CONCLUSIONS The density of the coronal pulp cells reduces and these cells undergo morphological changes with ageing of individuals and this may affect the pulp's ability to resist tooth injury.
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Affiliation(s)
- Sulinda Daud
- Dental Faculty, Segi University College, Petaling Jaya, Malaysia
| | - Prabhakaran Nambiar
- Department of Diagnostic Dental Practice, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia
| | - M Zakir Hossain
- Department of Oral Biology and Biomedical Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia
| | - Mas Rizal Ab Rahman
- Department of Oral Biology and Biomedical Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia
| | - Marina M Bakri
- Department of Oral Biology and Biomedical Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia
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20
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Houshmandi M, Ye P, Hunter N. Glial network responses to polymicrobial invasion of dentin. Caries Res 2014; 48:534-48. [PMID: 24993646 DOI: 10.1159/000360610] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 02/08/2014] [Indexed: 11/19/2022] Open
Abstract
This study investigated the distribution patterns of glial networks disclosed by reactivity for glial fibrillary acidic protein (GFAP) and S100B in healthy and carious human teeth. The objective was to determine the assembly and collapse of glial networks in response to encroaching infection. 15 healthy and 37 carious posterior teeth from adults were studied. Immediately after extraction, teeth were cleaned and vertically split and the half with pulp fixed and prepared for resin or frozen sections. Sections were stained with toluidine blue and for immunofluorescence, with observation by confocal laser microscopy and analysis by ImageJ software. Carious teeth were subdivided into three groups according to degree of carious involvement: microbial penetration through enamel (stage A), extension into dentin (stage B) and advanced penetration into dentin but without invasion of underlying pulp tissue (stage C). In stage A lesions there was marked increase in glial networks in dental pulp tissue that extended beyond the zone of microbial invasion. This response was maintained in stage B lesions. In advanced stage C lesions these networks were degraded in the zone of invasion in association with failure to contain infection. Cells expressing the glial markers GFAP and S100B showed a response to initial microbial invasion of dentin by increase in number and altered anatomical arrangement. The late stage of dentinal caries was marked by collapse of these networks in the region adjacent to advancing bacteria. This behaviour is important for understanding and explaining the defensive response of the neurosensory peripheral dental pulp apparatus to infection.
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Affiliation(s)
- Mojgan Houshmandi
- Institute of Dental Research, Westmead Millennium Institute and Westmead Centre for Oral Health, Westmead Hospital, Westmead, N.S.W., Australia
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21
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Lesot H, Hovorakova M, Peterka M, Peterkova R. Three-dimensional analysis of molar development in the mouse from the cap to bell stage. Aust Dent J 2014; 59 Suppl 1:81-100. [DOI: 10.1111/adj.12132] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- H Lesot
- Institut National de la Santé et de la Recherche Médicale; UMR 1109, Team ‘Osteoarticular and Dental Regenerative NanoMedicine’; Strasbourg France
- Université de Strasbourg; Faculté de Chirurgie Dentaire; Strasbourg France
| | - M Hovorakova
- Department of Teratology; Institute of Experimental Medicine, Academy of Sciences of the Czech Republic; Prague Czech Republic
| | - M Peterka
- Department of Teratology; Institute of Experimental Medicine, Academy of Sciences of the Czech Republic; Prague Czech Republic
| | - R Peterkova
- Department of Teratology; Institute of Experimental Medicine, Academy of Sciences of the Czech Republic; Prague Czech Republic
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22
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Kökten T, Bécavin T, Keller L, Weickert JL, Kuchler-Bopp S, Lesot H. Immunomodulation stimulates the innervation of engineered tooth organ. PLoS One 2014; 9:e86011. [PMID: 24465840 PMCID: PMC3899083 DOI: 10.1371/journal.pone.0086011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 12/04/2013] [Indexed: 01/24/2023] Open
Abstract
The sensory innervation of the dental mesenchyme is essential for tooth function and protection. Sensory innervation of the dental pulp is mediated by axons originating from the trigeminal ganglia and is strictly regulated in time. Teeth can develop from cultured re-associations between dissociated dental epithelial and mesenchymal cells from Embryonic Day 14 mouse molars, after implantation under the skin of adult ICR mice. In these conditions however, the innervation of the dental mesenchyme did not occur spontaneously. In order to go further with this question, complementary experimental approaches were designed. Cultured cell re-associations were implanted together with trigeminal ganglia for one or two weeks. Although axonal growth was regularly observed extending from the trigeminal ganglia to all around the forming teeth, the presence of axons in the dental mesenchyme was detected in less than 2.5% of samples after two weeks, demonstrating a specific impairment of their entering the dental mesenchyme. In clinical context, immunosuppressive therapy using cyclosporin A was found to accelerate the innervation of transplanted tissues. Indeed, when cultured cell re-associations and trigeminal ganglia were co-implanted in cyclosporin A-treated ICR mice, nerve fibers were detected in the dental pulp, even reaching odontoblasts after one week. However, cyclosporin A shows multiple effects, including direct ones on nerve growth. To test whether there may be a direct functional relationship between immunomodulation and innervation, cell re-associations and trigeminal ganglia were co-implanted in immunocompromised Nude mice. In these conditions as well, the innervation of the dental mesenchyme was observed already after one week of implantation, but axons reached the odontoblast layer after two weeks only. This study demonstrated that immunodepression per se does stimulate the innervation of the dental mesenchyme.
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Affiliation(s)
- Tunay Kökten
- Institut National de la Santé Et de la Recherche Médicale (INSERM) Unité Mixte de Recherche (UMR)1109, team “Osteoarticular and Dental Regenerative NanoMedicine”, Faculté de Médecine, Université de Strasbourg, Strasbourg, France
- Faculté de Chirurgie Dentaire, Université de Strasbourg, Strasbourg, France
| | - Thibault Bécavin
- Institut National de la Santé Et de la Recherche Médicale (INSERM) Unité Mixte de Recherche (UMR)1109, team “Osteoarticular and Dental Regenerative NanoMedicine”, Faculté de Médecine, Université de Strasbourg, Strasbourg, France
| | - Laetitia Keller
- Institut National de la Santé Et de la Recherche Médicale (INSERM) Unité Mixte de Recherche (UMR)1109, team “Osteoarticular and Dental Regenerative NanoMedicine”, Faculté de Médecine, Université de Strasbourg, Strasbourg, France
| | - Jean-Luc Weickert
- Service de Microscopie Electronique, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM Unité (U)964, Centre National de la Recherche Scientifique (CNRS) UMR1704, Université de Strasbourg, Illkirch, France
| | - Sabine Kuchler-Bopp
- Institut National de la Santé Et de la Recherche Médicale (INSERM) Unité Mixte de Recherche (UMR)1109, team “Osteoarticular and Dental Regenerative NanoMedicine”, Faculté de Médecine, Université de Strasbourg, Strasbourg, France
- Faculté de Chirurgie Dentaire, Université de Strasbourg, Strasbourg, France
| | - Hervé Lesot
- Institut National de la Santé Et de la Recherche Médicale (INSERM) Unité Mixte de Recherche (UMR)1109, team “Osteoarticular and Dental Regenerative NanoMedicine”, Faculté de Médecine, Université de Strasbourg, Strasbourg, France
- Faculté de Chirurgie Dentaire, Université de Strasbourg, Strasbourg, France
- * E-mail:
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23
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Abstract
Odontoblasts are dentin-secreting cells that survive for the whole life of a healthy tooth. Once teeth are completely erupted, odontoblasts transform into a mature stage that allows for their functional conservation for decades, while maintaining the capacity for secondary and reactionary dentin secretion. Odontoblasts are also critically involved in the transmission of sensory stimuli from the dentin-pulp complex and in the cellular defense against pathogens. Their longevity is sustained by an elaborate autophagic-lysosomal system that ensures organelle and protein renewal. However, progressive dysfunction of this system, in part caused by lipofuscin accumulation, reduces the fitness of odontoblasts and eventually impairs their dentin maintenance capacity. Here we review the functional activities assumed by mature odontoblasts throughout life. Understanding the biological basis of age-related changes in human odontoblasts is crucial to improving tooth preservation in the elderly.
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Affiliation(s)
- E. Couve
- Departamento de Biología, Laboratorio de Microscopía Electrónica
- Facultad de Ciencias, Universidad de Valparaíso, Avda. Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile
| | - R. Osorio
- Departamento de Biología, Laboratorio de Microscopía Electrónica
- Facultad de Ciencias, Universidad de Valparaíso, Avda. Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile
| | - O. Schmachtenberg
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV)
- Facultad de Ciencias, Universidad de Valparaíso, Avda. Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile
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24
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Gopinathan G, Kolokythas A, Luan X, Diekwisch TGH. Epigenetic marks define the lineage and differentiation potential of two distinct neural crest-derived intermediate odontogenic progenitor populations. Stem Cells Dev 2013; 22:1763-78. [PMID: 23379639 DOI: 10.1089/scd.2012.0711] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Epigenetic mechanisms, such as histone modifications, play an active role in the differentiation and lineage commitment of mesenchymal stem cells. In the present study, epigenetic states and differentiation profiles of two odontogenic neural crest-derived intermediate progenitor populations were compared: dental pulp (DP) and dental follicle (DF). ChIP on chip assays revealed substantial H3K27me3-mediated repression of odontoblast lineage genes DSPP and dentin matrix protein 1 (DMP1) in DF cells, but not in DP cells. Mineralization inductive conditions caused steep increases of mineralization and patterning gene expression levels in DP cells when compared to DF cells. In contrast, mineralization induction resulted in a highly dynamic histone modification response in DF cells, while there was only a subdued effect in DP cells. Both DF and DP progenitors featured H3K4me3-active marks on the promoters of early mineralization genes RUNX2, MSX2, and DLX5, while OSX, IBSP, and BGLAP promoters were enriched for H3K9me3 or H3K27me3. Compared to DF cells, DP cells expressed higher levels of three pluripotency-associated genes, OCT4, NANOG, and SOX2. Finally, gene ontology comparison of bivalent marks unique for DP and DF cells highlighted cell-cell attachment genes in DP cells and neurogenesis genes in DF cells. In conclusion, the present study indicates that the DF intermediate odontogenic neural crest lineage is distinguished from its DP counterpart by epigenetic repression of DSPP and DMP1 genes and through dynamic histone enrichment responses to mineralization induction. Findings presented here highlight the crucial role of epigenetic regulatory mechanisms in the terminal differentiation of odontogenic neural crest lineages.
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Affiliation(s)
- Gokul Gopinathan
- UIC Brodie Laboratory for Craniofacial Genetics, UIC College of Dentistry, Chicago, Illinois 60612, USA
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Charadram N, Austin C, Trimby P, Simonian M, Swain MV, Hunter N. Structural analysis of reactionary dentin formed in response to polymicrobial invasion. J Struct Biol 2013; 181:207-22. [PMID: 23261402 PMCID: PMC3578079 DOI: 10.1016/j.jsb.2012.12.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2012] [Revised: 12/06/2012] [Accepted: 12/08/2012] [Indexed: 11/23/2022]
Abstract
In response to microbial invasion of dentin odontoblasts secrete an altered calcified matrix termed reactionary dentin (Rd). 3D reconstruction of focused-ion-beam scanning electron microscopy (FIB-SEM) image slices revealed helical tubular structures in Rd that contrasted with regular cylindrical tubules characteristic of dentin from healthy teeth and affected so-called physiological dentin (Pd) lying exterior to Rd. This helical structure in Rd provided effective constriction of tubule lumen diameter that formed a barrier to bacterial advance towards the dental pulp. SEM of resin cast preparations revealed altered extension of odontoblast processes through Rd. The distribution of key mineral elements was studied by combination of 3D reconstruction of focused-ion-beam based X-ray microanalysis (FIB-EDS), laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). There was a marked redistribution of calcium and phosphorous in Rd together with an increase of diffusely deposited magnesium compatible with the mineral deposition phase of synthesis of this altered matrix. Changes in tubule structure and mineral content characteristic of Rd are consistent with reduced hardness and lower elastic modulus reported for this matrix. Findings provide insight into the unique structure of Rd synthesised as a primary response to infection.
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Affiliation(s)
- Nattida Charadram
- Institute of Dental Research, Westmead Millennium Institute and Westmead Centre for Oral Health, Westmead, Sydney, New South Wales, Australia
- Faculty of Dentistry, University of Sydney, Sydney, New South Wales, Australia
| | - Christine Austin
- Institute of Dental Research, Westmead Millennium Institute and Westmead Centre for Oral Health, Westmead, Sydney, New South Wales, Australia
- Elemental Bio-imaging Facility, Department of Chemistry and Forensic Science, University of Technology Sydney, New South Wales, Australia
| | - Patrick Trimby
- Australian Centre For Microscopy & Microanalysis, University of Sydney, Sydney, New South Wales, Australia
| | - Mary Simonian
- Institute of Dental Research, Westmead Millennium Institute and Westmead Centre for Oral Health, Westmead, Sydney, New South Wales, Australia
| | - Michael V. Swain
- Faculty of Dentistry, University of Sydney, Sydney, New South Wales, Australia
| | - Neil Hunter
- Institute of Dental Research, Westmead Millennium Institute and Westmead Centre for Oral Health, Westmead, Sydney, New South Wales, Australia
- Faculty of Dentistry, University of Sydney, Sydney, New South Wales, Australia
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Directed glia-assisted angiogenesis in a mature neurosensory structure: Pericytes mediate an adaptive response in human dental pulp that maintains blood-barrier function. J Comp Neurol 2012; 520:3803-26. [DOI: 10.1002/cne.23162] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Tsumura M, Sobhan U, Muramatsu T, Sato M, Ichikawa H, Sahara Y, Tazaki M, Shibukawa Y. TRPV1-mediated calcium signal couples with cannabinoid receptors and sodium-calcium exchangers in rat odontoblasts. Cell Calcium 2012; 52:124-36. [PMID: 22656960 DOI: 10.1016/j.ceca.2012.05.002] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Revised: 04/24/2012] [Accepted: 05/02/2012] [Indexed: 11/30/2022]
Abstract
Odontoblasts are involved in the transduction of stimuli applied to exposed dentin. Although expression of thermo/mechano/osmo-sensitive transient receptor potential (TRP) channels has been demonstrated, the properties of TRP vanilloid 1 (TRPV1)-mediated signaling remain to be clarified. We investigated physiological and pharmacological properties of TRPV1 and its functional coupling with cannabinoid (CB) receptors and Na(+)-Ca(2+) exchangers (NCXs) in odontoblasts. Anandamide (AEA), capsaicin (CAP), resiniferatoxin (RF) or low-pH evoked Ca(2+) influx. This influx was inhibited by capsazepine (CPZ). Delay in time-to-activation of TRPV1 channels was observed between application of AEA or CAP and increase in [Ca(2+)](i). In the absence of extracellular Ca(2+), however, an immediate increase in [Ca(2+)](i) was observed on administration of extracellular Ca(2+), followed by activation of TRPV1 channels. Intracellular application of CAP elicited inward current via opening of TRPV1 channels faster than extracellular application. With extracellular RF application, no time delay was observed in either increase in [Ca(2+)](i) or inward current, indicating that agonist binding sites are located on both extra- and intracellular domains. KB-R7943, an NCX inhibitor, yielded an increase in the decay time constant during TRPV1-mediated Ca(2+) entry. Increase in [Ca(2+)](i) by CB receptor agonist, 2-arachidonylglycerol, was inhibited by CB1 receptor antagonist or CPZ, as well as by adenylyl cyclase inhibitor. These results showed that TRPV1-mediated Ca(2+) entry functionally couples with CB1 receptor activation via cAMP signaling. Increased [Ca(2+)](i) by TRPV1 activation was extruded by NCXs. Taken together, this suggests that cAMP-mediated CB1-TRPV1 crosstalk and TRPV1-NCX coupling play an important role in driving cellular functions following transduction of external stimuli to odontoblasts.
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Affiliation(s)
- Maki Tsumura
- Oral Health Science Center hrc8, Tokyo Dental College, Chiba, Japan
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Couve E, Osorio R, Schmachtenberg O. Mitochondrial Autophagy and Lipofuscin Accumulation in Aging Odontoblasts. J Dent Res 2012; 91:696-701. [DOI: 10.1177/0022034512449347] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Aging of long-lived post-mitotic cells is characterized as a progressive and irreversible reduction of functional activity. In such cells, mitochondria are organelles critical for bioenergetic supply, whose turnover is mediated by an autophagic-lysosomal pathway. In human teeth, odontoblasts are post-mitotic cells responsible for sensory function and dentin preservation. Here, human odontoblasts were processed for immunohistochemistry with antibodies against mitochondrial (MTCO2) and lysosomal (LAMP2) markers, and comparatively analyzed in two age groups (young-adult and adult) with light and electron microscopy. Selective engulfment of mitochondrial profiles into autophagic vacuoles is common in young-adult odontoblasts, suggesting a microautophagic pathway. With age, the odontoblast layer is reduced in width, and mitochondrial elements converge around large clusters of autofluorescent lipofuscin deposits. Age-related changes in odontoblasts are observed as a long-term process in which the progressive accumulation of intralysosomal debris limits the autophagic turnover of mitochondrial components, causing an eventual decline in physiological cell functions, which leads to increased vulnerability under stress conditions.
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Affiliation(s)
- E. Couve
- Departamento de Biología y Cs. Ambientales, Laboratorio de Microscopía Electrónica, Chile
- Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - R. Osorio
- Departamento de Biología y Cs. Ambientales, Laboratorio de Microscopía Electrónica, Chile
- Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - O. Schmachtenberg
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Chile
- Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
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