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Zaraisky AG, Araslanova KR, Shitikov AD, Tereshina MB. Loss of the ability to regenerate body appendages in vertebrates: from side effects of evolutionary innovations to gene loss. Biol Rev Camb Philos Soc 2024. [PMID: 38817123 DOI: 10.1111/brv.13102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 05/04/2024] [Accepted: 05/14/2024] [Indexed: 06/01/2024]
Abstract
The ability to regenerate large body appendages is an ancestral trait of vertebrates, which varies across different animal groups. While anamniotes (fish and amphibians) commonly possess this ability, it is notably restricted in amniotes (reptiles, birds, and mammals). In this review, we explore the factors contributing to the loss of regenerative capabilities in amniotes. First, we analyse the potential negative impacts on appendage regeneration caused by four evolutionary innovations: advanced immunity, skin keratinization, whole-body endothermy, and increased body size. These innovations emerged as amniotes transitioned to terrestrial habitats and were correlated with a decline in regeneration capability. Second, we examine the role played by the loss of regeneration-related enhancers and genes initiated by these innovations in the fixation of an inability to regenerate body appendages at the genomic level. We propose that following the cessation of regenerative capacity, the loss of highly specific regeneration enhancers could represent an evolutionarily neutral event. Consequently, the loss of such enhancers might promptly follow the suppression of regeneration as a side effect of evolutionary innovations. By contrast, the loss of regeneration-related genes, due to their pleiotropic functions, would only take place if such loss was accompanied by additional evolutionary innovations that compensated for the loss of pleiotropic functions unrelated to regeneration, which would remain even after participation of these genes in regeneration was lost. Through a review of the literature, we provide evidence that, in many cases, the loss in amniotes of genes associated with body appendage regeneration in anamniotes was significantly delayed relative to the time when regenerative capability was lost. We hypothesise that this delay may be attributed to the necessity for evolutionary restructuring of developmental mechanisms to create conditions where the loss of these genes was a beneficial innovation for the organism. Experimental investigation of the downregulation of genes involved in the regeneration of body appendages in anamniotes but absent in amniotes offers a promising avenue to uncover evolutionary innovations that emerged from the loss of these genes. We propose that the vast majority of regeneration-related genes lost in amniotes (about 150 in humans) may be involved in regulating the early stages of limb and tail regeneration in anamniotes. Disruption of this stage, rather than the late stage, may not interfere with the mechanisms of limb and tail bud development during embryogenesis, as these mechanisms share similarities with those operating in the late stage of regeneration. Consequently, the most promising approach to restoring regeneration in humans may involve creating analogs of embryonic limb buds using stem cell-based tissue-engineering methods, followed by their transfer to the amputation stump. Due to the loss of many genes required specifically during the early stage of regeneration, this approach may be more effective than attempting to induce both early and late stages of regeneration directly in the stump itself.
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Affiliation(s)
- Andrey G Zaraisky
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya str., Moscow, 117997, Russia
- Pirogov Russian National Research Medical University, 1 Ostrovityanova str., Moscow, 117997, Russia
| | - Karina R Araslanova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya str., Moscow, 117997, Russia
| | - Alexander D Shitikov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya str., Moscow, 117997, Russia
| | - Maria B Tereshina
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya str., Moscow, 117997, Russia
- Pirogov Russian National Research Medical University, 1 Ostrovityanova str., Moscow, 117997, Russia
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2
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Noble A, Qubrosi R, Cariba S, Favaro K, Payne SL. Neural dependency in wound healing and regeneration. Dev Dyn 2024; 253:181-203. [PMID: 37638700 DOI: 10.1002/dvdy.650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 07/31/2023] [Accepted: 08/02/2023] [Indexed: 08/29/2023] Open
Abstract
In response to injury, humans and many other mammals form a fibrous scar that lacks the structure and function of the original tissue, whereas other vertebrate species can spontaneously regenerate damaged tissues and structures. Peripheral nerves have been identified as essential mediators of wound healing and regeneration in both mammalian and nonmammalian systems, interacting with the milieu of cells and biochemical signals present in the post-injury microenvironment. This review examines the diverse functions of peripheral nerves in tissue repair and regeneration, specifically during the processes of wound healing, blastema formation, and organ repair. We compare available evidence in mammalian and nonmammalian models, identifying critical nerve-mediated mechanisms for regeneration and providing future perspectives toward integrating these mechanisms into a therapeutic framework to promote regeneration.
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Affiliation(s)
- Alexandra Noble
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Rozana Qubrosi
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Solsa Cariba
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Kayla Favaro
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Samantha L Payne
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, Canada
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3
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Lin X, Lai Y. Scarring Skin: Mechanisms and Therapies. Int J Mol Sci 2024; 25:1458. [PMID: 38338767 PMCID: PMC10855152 DOI: 10.3390/ijms25031458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 01/19/2024] [Accepted: 01/20/2024] [Indexed: 02/12/2024] Open
Abstract
Skin injury always results in fibrotic, non-functional scars in adults. Although multiple factors are well-known contributors to scar formation, the precise underlying mechanisms remain elusive. This review aims to elucidate the intricacies of the wound healing process, summarize the known factors driving skin cells in wounds toward a scarring fate, and particularly to discuss the impact of fibroblast heterogeneity on scar formation. To the end, we explore potential therapeutic interventions used in the treatment of scarring wounds.
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Affiliation(s)
- Xinye Lin
- Shanghai Key Laboratory of Regulatory Biology, School of Life Sciences, East China Normal University, Shanghai 200241, China;
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Yuping Lai
- Shanghai Key Laboratory of Regulatory Biology, School of Life Sciences, East China Normal University, Shanghai 200241, China;
- Shanghai Frontiers Science Center of Genome Editing and Cell Therapy, School of Life Sciences, East China Normal University, Shanghai 200241, China
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4
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Sarkovich S, Issa PP, Longanecker A, Martin D, Redondo K, McTernan P, Simkin J, Marrero L. Minoxidil weakens newly synthesized collagen in fibrotic synoviocytes from osteoarthritis patients. J Exp Orthop 2023; 10:84. [PMID: 37605092 PMCID: PMC10441905 DOI: 10.1186/s40634-023-00650-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 08/09/2023] [Indexed: 08/23/2023] Open
Abstract
PURPOSE Synovial fibrosis (SFb) formation and turnover attributable to knee osteoarthritis (KOA) can impart painful stiffness and persist following arthroplasty. To supplement joint conditioning aimed at maximizing peri-operative function, we evaluated the antifibrotic effect of Minoxidil (MXD) on formation of pyridinoline (Pyd) cross-links catalyzed by Plod2-encoded lysyl hydroxylase (LH)2b that strengthen newly synthesized type-I collagen (COL1) in fibroblastic synovial cells (FSCs) from KOA patients. MXD was predicted to decrease Pyd without significant alterations to Col1a1 transcription by FSCs stimulated with transforming growth factor (TGF)β1. METHODS Synovium from 10 KOA patients grouped by SFb severity was preserved for picrosirius and LH2b histology or culture. Protein and RNA were purified from fibrotic FSCs after 8 days with or without 0.5 µM MXD and/or 4 ng/mL of TGFβ1. COL1 and Pyd protein concentrations from ELISA and expression of Col1a1, Acta2, and Plod2 genes by qPCR were compared by parametric tests with α = 0.05. RESULTS Histological LH2b expression corresponded to SFb severity. MXD attenuated COL1 output in KOA FSCs but only in the absence of TGFβ1 and consistently decreased Pyd under all conditions with significant downregulation of Plod2 but minimal alterations to Col1a1 and Acta2 transcripts. CONCLUSIONS MXD is an attractive candidate for local antifibrotic pharmacotherapy for SFb by compromising the integrity of newly formed fibrous deposits by FSCs during KOA and following arthroplasty. Targeted antifibrotic supplementation could improve physical therapy and arthroscopic lysis strategies aimed at breaking down joint scarring. However, the effect of MXD on other joint-specific TGFβ1-mediated processes or non-fibrotic components requires further investigation.
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Affiliation(s)
- Stefan Sarkovich
- Department of Orthopaedic Surgery, Louisiana State University Health Sciences Center, 2021 Perdido St., Center for Advanced Learning and Simulation, 7th floor, New Orleans, LA, 70112, USA
| | - Peter P Issa
- School of Medicine, Louisiana State University Health Sciences Center, 2020 Gravier St., Lions Building, 5th floor, New Orleans, LA, 70112, USA
| | - Andrew Longanecker
- School of Medicine, Louisiana State University Health Sciences Center, 2020 Gravier St., Lions Building, 5th floor, New Orleans, LA, 70112, USA
| | - Davis Martin
- School of Medicine, Louisiana State University Health Sciences Center, 2020 Gravier St., Lions Building, 5th floor, New Orleans, LA, 70112, USA
| | - Kaitlyn Redondo
- Morphology and Imaging Core, Louisiana State University Health Sciences Center, 533 Bolivar St., Clinical Sciences Research Building, 5th floor, New Orleans, LA, 70112, USA
| | - Patrick McTernan
- Department of Physiology, Louisiana State University Health Sciences Center, 533 Bolivar St., Clinical Sciences Research Building, 4th floor, New Orleans, LA, 70112, USA
| | - Jennifer Simkin
- Department of Orthopaedic Surgery, Louisiana State University Health Sciences Center, 2021 Perdido St., Center for Advanced Learning and Simulation, 7th floor, New Orleans, LA, 70112, USA
| | - Luis Marrero
- Department of Orthopaedic Surgery, Louisiana State University Health Sciences Center, 2021 Perdido St., Center for Advanced Learning and Simulation, 7th floor, New Orleans, LA, 70112, USA.
- School of Medicine, Louisiana State University Health Sciences Center, 2020 Gravier St., Lions Building, 5th floor, New Orleans, LA, 70112, USA.
- Morphology and Imaging Core, Louisiana State University Health Sciences Center, 533 Bolivar St., Clinical Sciences Research Building, 5th floor, New Orleans, LA, 70112, USA.
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5
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Jou V, Lehoczky JA. Toeing the line between regeneration and fibrosis. Front Cell Dev Biol 2023; 11:1217185. [PMID: 37325560 PMCID: PMC10267333 DOI: 10.3389/fcell.2023.1217185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 05/23/2023] [Indexed: 06/17/2023] Open
Abstract
Understanding the remarkable capacity of vertebrates to naturally regenerate injured body parts has great importance for potential translation into human therapeutic applications. As compared to other vertebrates, mammals have low regenerative capacity for composite tissues like the limb. However, some primates and rodents can regenerate the distal tips of their digits following amputation, indicating that at least very distal mammalian limb tissues are competent for innate regeneration. It follows that successful digit tip regenerative outcome is highly dependent on the location of the amputation; those proximal to the position of the nail organ do not regenerate and result in fibrosis. This distal regeneration versus proximal fibrosis duality of the mouse digit tip serves as a powerful model to investigate the driving factors in determining each process. In this review, we present the current understanding of distal digit tip regeneration in the context of cellular heterogeneity and the potential for different cell types to function as progenitor cells, in pro-regenerative signaling, or in moderating fibrosis. We then go on to discuss these themes in the context of what is known about proximal digit fibrosis, towards generating hypotheses for these distinct healing processes in the distal and proximal mouse digit.
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Affiliation(s)
- Vivian Jou
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, United States
- Department of Orthopedic Surgery, Brigham and Women’s Hospital, Boston, MA, United States
| | - Jessica A. Lehoczky
- Department of Orthopedic Surgery, Brigham and Women’s Hospital, Boston, MA, United States
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6
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Castilla-Ibeas A, Zdral S, Galán L, Haro E, Allou L, Campa VM, Icardo JM, Mundlos S, Oberg KC, Ros MA. Failure of digit tip regeneration in the absence of Lmx1b suggests Lmx1b functions disparate from dorsoventral polarity. Cell Rep 2023; 42:111975. [PMID: 36641754 DOI: 10.1016/j.celrep.2022.111975] [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: 05/04/2022] [Revised: 11/07/2022] [Accepted: 12/22/2022] [Indexed: 01/15/2023] Open
Abstract
Mammalian digit tip regeneration is linked to the presence of nail tissue, but a nail-explicit model is missing. Here, we report that nail-less double-ventral digits of ΔLARM1/2 mutants that lack limb-specific Lmx1b enhancers fail to regenerate. To separate the nail's effect from the lack of dorsoventral (DV) polarity, we also interrogate double-dorsal double-nail digits and show that they regenerate. Thus, DV polarity is not a prerequisite for regeneration, and the nail requirement is supported. Transcriptomic comparison between wild-type and non-regenerative ΔLARM1/2 mutant blastemas reveals differential upregulation of vascularization and connective tissue functional signatures in wild type versus upregulation of inflammation in the mutant. These results, together with the finding of Lmx1b expression in the postnatal dorsal dermis underneath the nail and uniformly in the regenerative blastema, open the possibility of additional Lmx1b roles in digit tip regeneration, in addition to the indirect effect of mediating the formation of the nail.
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Affiliation(s)
- Alejandro Castilla-Ibeas
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC; CSIC-SODERCAN-UC), Santander, Spain
| | - Sofía Zdral
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC; CSIC-SODERCAN-UC), Santander, Spain
| | - Laura Galán
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC; CSIC-SODERCAN-UC), Santander, Spain
| | - Endika Haro
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC; CSIC-SODERCAN-UC), Santander, Spain
| | - Lila Allou
- RG Development & Disease, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Víctor M Campa
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC; CSIC-SODERCAN-UC), Santander, Spain
| | - Jose M Icardo
- Departamento de Anatomía y Biología Celular, Universidad de Cantabria, Santander, Spain
| | - Stefan Mundlos
- RG Development & Disease, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Kerby C Oberg
- Department of Pathology and Human Anatomy, School of Medicine, Loma Linda University, Loma Linda, CA, USA
| | - Marian A Ros
- Instituto de Biomedicina y Biotecnología de Cantabria (IBBTEC; CSIC-SODERCAN-UC), Santander, Spain.
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7
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Johnson GL, Glasser MB, Charles JF, Duryea J, Lehoczky JA. En1 and Lmx1b do not recapitulate embryonic dorsal-ventral limb patterning functions during mouse digit tip regeneration. Cell Rep 2022; 41:111701. [PMID: 36417876 PMCID: PMC9727699 DOI: 10.1016/j.celrep.2022.111701] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 09/09/2022] [Accepted: 10/31/2022] [Indexed: 11/23/2022] Open
Abstract
The mouse digit tip regenerates following amputation. How the regenerate is patterned is unknown, but a long-standing hypothesis proposes developmental patterning mechanisms are re-used during regeneration. The digit tip bone exhibits dorsal-ventral (DV) polarity, so we focus on En1 and Lmx1b, two factors necessary for DV patterning during limb development. We investigate whether they are re-expressed during regeneration in a developmental-like pattern and whether they direct DV morphology of the regenerate. We find that both En1 and Lmx1b are expressed in the regenerating digit tip epithelium and mesenchyme, respectively, but without DV polarity. Conditional genetics and quantitative analysis of digit tip bone morphology determine that genetic deletion of En1 or Lmx1b in adult digit tip regeneration modestly reduces bone regeneration but does not affect DV patterning. Collectively, our data suggest that, while En1 and Lmx1b are re-expressed during mouse digit tip regeneration, they do not define the DV axis during regeneration.
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Affiliation(s)
- Gemma L. Johnson
- Department of Orthopedic Surgery, Brigham and Women’s Hospital, Boston, MA 02115, USA,Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Morgan B. Glasser
- Department of Orthopedic Surgery, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Julia F. Charles
- Department of Orthopedic Surgery, Brigham and Women’s Hospital, Boston, MA 02115, USA,Department of Medicine, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Jeffrey Duryea
- Department of Radiology, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Jessica A. Lehoczky
- Department of Orthopedic Surgery, Brigham and Women’s Hospital, Boston, MA 02115, USA,Lead contact,Correspondence:
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8
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Johnson GL, Lehoczky JA. Mammalian Digit Tip Regeneration: Moving from Phenomenon to Molecular Mechanism. Cold Spring Harb Perspect Biol 2022; 14:a040857. [PMID: 34312249 PMCID: PMC8725625 DOI: 10.1101/cshperspect.a040857] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
In this review, we present the current state of knowledge surrounding mammalian digit tip regeneration. We discuss the origin and formation of the blastema, a structure integral to digit tip regeneration, as well as recent insights driven by single-cell RNA sequencing into the molecular markers and cellular composition of the blastema. The digit tip is a composite of many different tissue types and we address what is known about the role of these separate tissues in regeneration of the whole digit tip. Specifically, we discuss the most extensively studied tissues in the digit tip: bone, nail epithelium, and peripheral nerves. We also address how known molecular pathways in limb development can inform research into digit tip regeneration. Overall, the mouse digit tip is an excellent model of complex mammalian regeneration that can provide insight into inducing regeneration in human tissues.
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Affiliation(s)
- Gemma L Johnson
- Department of Orthopedics, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Jessica A Lehoczky
- Department of Orthopedics, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
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9
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Schiavinato A, Przyklenk M, Kobbe B, Paulsson M, Wagener R. Collagen type VI is the antigen recognized by the ER-TR7 antibody. Eur J Immunol 2021; 51:2345-2347. [PMID: 34180542 DOI: 10.1002/eji.202149263] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 04/28/2021] [Accepted: 06/25/2021] [Indexed: 11/09/2022]
Abstract
The monoclonal antibody ER-TR7 was used in a great number of studies for detecting reticular fibroblasts and the ECM of lymphoid and non-lymphoid organs even if the protein recognized by the ER-TR7 antibody was not known. We have now identified native collagen VI microfibrils as its tissue antigen.
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Affiliation(s)
- Alvise Schiavinato
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany.,Istituto Di Patologia Clinica, Azienda Sanitaria Universitaria Integrata di Udine (ASUID), Udine, Italy
| | - Matthias Przyklenk
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany
| | - Birgit Kobbe
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany
| | - Mats Paulsson
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany.,Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.,Center for Musculoskeletal Biomechanics (CCMB), Medical Faculty, University of Cologne, Cologne, Germany
| | - Raimund Wagener
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany
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10
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The Potential of Nail Mini-Organ Stem Cells in Skin, Nail and Digit Tips Regeneration. Int J Mol Sci 2021; 22:ijms22062864. [PMID: 33799809 PMCID: PMC7998429 DOI: 10.3390/ijms22062864] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/08/2021] [Accepted: 03/08/2021] [Indexed: 12/17/2022] Open
Abstract
Nails are highly keratinized skin appendages that exhibit continuous growth under physiological conditions and full regeneration upon removal. These mini-organs are maintained by two autonomous populations of skin stem cells. The fast-cycling, highly proliferative stem cells of the nail matrix (nail stem cells (NSCs)) predominantly replenish the nail plate. Furthermore, the slow-cycling population of the nail proximal fold (nail proximal fold stem cells (NPFSCs)) displays bifunctional properties by contributing to the peri-nail epidermis under the normal homeostasis and the nail structure upon injury. Here, we discuss nail mini-organ stem cells’ location and their role in skin and nail homeostasis and regeneration, emphasizing their importance to orchestrate the whole digit tip regeneration. Such endogenous regeneration capabilities are observed in rodents and primates. However, they are limited to the region adjacent to the nail’s proximal area, indicating the crucial role of nail mini-organ stem cells in digit restoration. Further, we explore the molecular characteristics of nail mini-organ stem cells and the critical role of the bone morphogenetic protein (BMP) and Wnt signaling pathways in homeostatic nail growth and digit restoration. Finally, we investigate the latest accomplishments in stimulating regenerative responses in regeneration-incompetent injuries. These pioneer results might open up new opportunities to overcome amputated mammalian digits and limbs’ regenerative failures in the future.
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11
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Dawson LA, Schanes PP, Marrero L, Jordan K, Brunauer R, Zimmel KN, Qureshi O, Imholt FM, Falck AR, Yan M, Dolan CP, Yu L, Muneoka K. Proximal digit tip amputation initiates simultaneous blastema and transient fibrosis formation and results in partial regeneration. Wound Repair Regen 2020; 29:196-205. [PMID: 32815252 DOI: 10.1111/wrr.12856] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 07/09/2020] [Accepted: 07/23/2020] [Indexed: 12/14/2022]
Abstract
Complete extremity regeneration in mammals is restricted to distal amputations of the digit tip, the terminal phalanx (P3). In mice, P3 regeneration is mediated via the formation of a blastema, a transient population of progenitor cells that form from the blending of periosteal and endosteal/marrow compartmentalized cells that undergo differentiation to restore the amputated structures. Compartmentalized blastema cells are formed independently, and periosteal compartment-derived cells are required for restoration of amputated skeletal length. P3 regenerative capacity is progressively attenuated at increasingly more proximal amputation levels, eventually resulting in regenerative failure. The continuum of regenerative capacity within the P3 wound milieu is a unique model to investigate mammalian blastema formation in response to distal amputation, as well as the healing response associated with regenerative failure at proximal amputation levels. We report that P3 proximal amputation healing, previously reported to result in regenerative failure, is not an example of complete regenerative failure, but instead is characterized by a limited bone regeneration response restricted to the endosteal/marrow compartment. The regeneration response is mediated by blastema formation within the endosteal/marrow compartment, and blastemal osteogenesis progresses through intramembranous ossification in a polarized proximal to distal sequence. Unlike bone regeneration following distal P3 amputation, osteogenesis within the periosteal compartment is not observed in response to proximal P3 amputation. We provide evidence that proximal P3 amputation initiates the formation of fibrotic tissue that isolates the endosteal/marrow compartment from the periosteal compartment and wound epidermis. While the fibrotic response is transient and later resolved, these studies demonstrate that blastema formation and fibrosis can occur in close proximity, with the regenerative response dominating the final outcome. Moreover, the results suggest that the attenuated proximal P3 regeneration response is associated with the absence of periosteal-compartment participation in blastema formation and bone regeneration.
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Affiliation(s)
- Lindsay A Dawson
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Paula P Schanes
- Department of Cell and Molecular Biology, Tulane University, New Orleans, Louisiana, USA
| | - Luis Marrero
- Department of Orthopedic Surgery, Louisiana State University School of Medicine, New Orleans, Louisiana, USA.,Department of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA
| | - Kathryn Jordan
- Department of Orthopedic Surgery, Louisiana State University School of Medicine, New Orleans, Louisiana, USA.,Department of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA.,College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Regina Brunauer
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Katherine N Zimmel
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Osama Qureshi
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Felisha M Imholt
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Alyssa R Falck
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Mingquan Yan
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Connor P Dolan
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Ling Yu
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Ken Muneoka
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
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12
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Monavarian M, Kader S, Moeinzadeh S, Jabbari E. Regenerative Scar-Free Skin Wound Healing. TISSUE ENGINEERING PART B-REVIEWS 2020; 25:294-311. [PMID: 30938269 DOI: 10.1089/ten.teb.2018.0350] [Citation(s) in RCA: 111] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
IMPACT STATEMENT Millions of people every year develop scars in response to skin injuries after surgery, trauma, or burns with significant undesired physical and psychological effects. This review provides an update on engineering strategies for scar-free wound healing and discusses the role of different cell types, growth factors, cytokines, and extracellular components in regenerative wound healing. The use of pro-regenerative matrices combined with engineered cells with less intrinsic potential for fibrogenesis is a promising strategy for achieving scar-free skin tissue regeneration.
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Affiliation(s)
- Mehri Monavarian
- 1Biomimetic Materials and Tissue Engineering Laboratory, Department of Chemical Engineering, University of South Carolina, Columbia, South Carolina
| | - Safaa Kader
- 1Biomimetic Materials and Tissue Engineering Laboratory, Department of Chemical Engineering, University of South Carolina, Columbia, South Carolina.,2Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina
| | - Seyedsina Moeinzadeh
- 1Biomimetic Materials and Tissue Engineering Laboratory, Department of Chemical Engineering, University of South Carolina, Columbia, South Carolina
| | - Esmaiel Jabbari
- 1Biomimetic Materials and Tissue Engineering Laboratory, Department of Chemical Engineering, University of South Carolina, Columbia, South Carolina
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13
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Qu F, Palte IC, Gontarz PM, Zhang B, Guilak F. Transcriptomic analysis of bone and fibrous tissue morphogenesis during digit tip regeneration in the adult mouse. FASEB J 2020; 34:9740-9754. [PMID: 32506623 DOI: 10.1096/fj.202000330r] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 04/29/2020] [Accepted: 05/15/2020] [Indexed: 12/31/2022]
Abstract
Humans have limited regenerative potential of musculoskeletal tissues following limb or digit loss. The murine digit has been used to study mammalian regeneration, where stem/progenitor cells (the "blastema") completely regenerate the digit tip after distal, but not proximal, amputation. However, the molecular mechanisms responsible for this response remain to be determined. Here, we evaluated the spatiotemporal formation of bone and fibrous tissues after level-dependent amputation of the murine terminal phalanx and quantified the transcriptome of the repair tissue. Distal (regenerative) and proximal (non-regenerative) amputations showed significant differences in temporal gene expression and tissue regrowth over time. Genes that direct skeletal system development and limb morphogenesis are transiently upregulated during blastema formation and differentiation, including distal Hox genes. Overall, our results suggest that digit tip regeneration is controlled by a gene regulatory network that recapitulates aspects of limb development, and that failure to activate this developmental program results in fibrotic wound healing.
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Affiliation(s)
- Feini Qu
- Department of Orthopaedic Surgery, Washington University, St. Louis, MO, USA.,Center of Regenerative Medicine, Washington University, St. Louis, MO, USA.,Shriners Hospitals for Children-St. Louis, St. Louis, MO, USA
| | - Ilan C Palte
- Department of Orthopaedic Surgery, Washington University, St. Louis, MO, USA.,Center of Regenerative Medicine, Washington University, St. Louis, MO, USA.,Shriners Hospitals for Children-St. Louis, St. Louis, MO, USA
| | - Paul M Gontarz
- Center of Regenerative Medicine, Washington University, St. Louis, MO, USA
| | - Bo Zhang
- Center of Regenerative Medicine, Washington University, St. Louis, MO, USA
| | - Farshid Guilak
- Department of Orthopaedic Surgery, Washington University, St. Louis, MO, USA.,Center of Regenerative Medicine, Washington University, St. Louis, MO, USA.,Shriners Hospitals for Children-St. Louis, St. Louis, MO, USA
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14
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Johnson GL, Masias EJ, Lehoczky JA. Cellular Heterogeneity and Lineage Restriction during Mouse Digit Tip Regeneration at Single-Cell Resolution. Dev Cell 2020; 52:525-540.e5. [PMID: 32097654 PMCID: PMC7186907 DOI: 10.1016/j.devcel.2020.01.026] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 01/22/2020] [Accepted: 01/23/2020] [Indexed: 12/27/2022]
Abstract
Innate regeneration following digit tip amputation is one of the few examples of epimorphic regeneration in mammals. Digit tip regeneration is mediated by the blastema, the same structure invoked during limb regeneration in some lower vertebrates. By genetic lineage analyses, the digit tip blastema has been defined as a population of heterogeneous, lineage-restricted progenitor cells. These previous studies, however, do not comprehensively evaluate blastema heterogeneity or address lineage restriction of closely related cell types. In this report, we present single-cell RNA sequencing of over 38,000 cells from mouse digit tip blastemas and unamputated control digit tips and generate an atlas of the cell types participating in digit tip regeneration. We computationally define differentiation trajectories of vascular, monocytic, and fibroblastic lineages over regeneration, and while our data confirm broad lineage restriction of progenitors, our analysis reveals 67 genes enriched in blastema fibroblasts including a novel regeneration-specific gene, Mest.
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Affiliation(s)
- Gemma L Johnson
- Department of Orthopedic Surgery, Brigham and Women's Hospital, Boston, MA 02115, USA; Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Erick J Masias
- Department of Orthopedic Surgery, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Jessica A Lehoczky
- Department of Orthopedic Surgery, Brigham and Women's Hospital, Boston, MA 02115, USA.
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15
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Muneoka K, Dawson LA. Evolution of epimorphosis in mammals. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2020; 336:165-179. [PMID: 31951104 DOI: 10.1002/jez.b.22925] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 10/29/2019] [Accepted: 12/23/2019] [Indexed: 12/30/2022]
Abstract
Mammalian epimorphic regeneration is rare and digit tip regeneration in mice is the best-studied model for a multi-tissue regenerative event that involves blastema formation. Digit tip regeneration parallels human fingertip regeneration, thus understanding the details of this response can provide insight into developing strategies to expand the potential of human regeneration. Following amputation, the digit stump undergoes a strong histolytic response involving osteoclast-mediated bone degradation that is spatially and temporally linked to the expansion of blastema osteoprogenitor cells. Blastemal differentiation occurs via direct intramembranous ossification. Although robust, digit regeneration is imperfect: The amputated cortical bone is replaced with woven bone and there is excessive bone regeneration restricted to the dorsal-ventral axis. Ontogenetic and phylogenetic analysis of digit regeneration in amphibians and mammals raise the possibility that mammalian blastema is a product of convergent evolution and we hypothesize that digit tip regeneration evolved from a nonregenerative precondition. A model is proposed in which the mammalian blastema evolved in part from an adaptation of two bone repair strategies (the bone remodeling cycle and fracture healing) both of which are conserved across tetrapod vertebrates. The view that epimorphic regeneration evolved in mammals from a nonregenerative precondition is supported by recent studies demonstrating that complex regenerative responses can be induced from a number of different nonregenerative amputation wounds by specific modification of the healing response.
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Affiliation(s)
- Ken Muneoka
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas
| | - Lindsay A Dawson
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas
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16
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Identification of Heparan-Sulfate Rich Cells in the Loose Connective Tissues of the Axolotl (Ambystoma mexicanum) with the Potential to Mediate Growth Factor Signaling during Regeneration. REGENERATIVE ENGINEERING AND TRANSLATIONAL MEDICINE 2020; 6:7-17. [PMID: 33748405 DOI: 10.1007/s40883-019-00140-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Limb regeneration is the outcome of a complex sequence of events that are mediated by interactions between cells derived from the tissues of the amputated stump. Early in regeneration, these interactions are mediated by growth factor/morphogen signaling associated with nerves and the wound epithelium. One shared property of these proregenerative signaling molecules is that their activity is dependent on interactions with sulfated glycosaminoglycans (GAGs), heparan sulfate proteoglycan (HSPG) in particular, in the extracellular matrix (ECM). We hypothesized that there are cells in the axolotl that synthesize specific HSPGs that control growth factor signaling in time and space. In this study we have identified a subpopulation of cells within the ECM of axolotl skin that express high levels of sulfated GAGs on their cell surface. These cells are dispersed in a grid-like pattern throughout the dermis as well as the loose connective tissues that surround the tissues of the limb. These cells alter their morphology during regeneration, and are candidates for being a subpopulation of connective tissue cells that function as the cells required for pattern-formation during regeneration. Given their high level of HSPG expression, their stellate morphology, and their distribution throughout the loose connective tissues, we refer to these as the positional information GRID (Groups that are Regenerative, Interspersed and Dendritic) cells. In addition, we have identified cells that stain for high levels of expression of sulfated GAGs in mouse limb connective tissue that could have an equivalent function to GRID cells in the axolotl. The identification of GRID cells may have important implications for work in the area of Regenerative Engineering.
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17
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Oliveira KMC, Barker JH, Berezikov E, Pindur L, Kynigopoulos S, Eischen-Loges M, Han Z, Bhavsar MB, Henrich D, Leppik L. Electrical stimulation shifts healing/scarring towards regeneration in a rat limb amputation model. Sci Rep 2019; 9:11433. [PMID: 31391536 PMCID: PMC6685943 DOI: 10.1038/s41598-019-47389-w] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 07/16/2019] [Indexed: 12/19/2022] Open
Abstract
Different species respond differently to severe injury, such as limb loss. In species that regenerate, limb loss is met with complete restoration of the limbs’ form and function, whereas in mammals the amputated limb’s stump heals and scars. In in vitro studies, electrical stimulation (EStim) has been shown to promote cell migration, and osteo- and chondrogenesis. In in vivo studies, after limb amputation, EStim causes significant new bone, cartilage and vessel growth. Here, in a rat model, the stumps of amputated rat limbs were exposed to EStim, and we measured extracellular matrix (ECM) deposition, macrophage distribution, cell proliferation and gene expression changes at early (3 and 7 days) and later stages (28 days). We found that EStim caused differences in ECM deposition, with less condensed collagen fibrils, and modified macrophage response by changing M1 to M2 macrophage ratio. The number of proliferating cells was increased in EStim treated stumps 7 days after amputation, and transcriptome data strongly supported our histological findings, with activated gene pathways known to play key roles in embryonic development and regeneration. In conclusion, our findings support the hypothesis that EStim shifts injury response from healing/scarring towards regeneration. A better understanding of if and how EStim controls these changes, could lead to strategies that replace scarring with regeneration.
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Affiliation(s)
- K M C Oliveira
- Frankfurt Initiative for Regenerative Medicine, Experimental Orthopedics & Trauma Surgery, J.W. Goethe University, Frankfurt am Main, Germany
| | - J H Barker
- Frankfurt Initiative for Regenerative Medicine, Experimental Orthopedics & Trauma Surgery, J.W. Goethe University, Frankfurt am Main, Germany
| | - E Berezikov
- European Research Institute for the Biology of Ageing, University Medical Center Groningen, Groningen, The Netherlands
| | - L Pindur
- Frankfurt Initiative for Regenerative Medicine, Experimental Orthopedics & Trauma Surgery, J.W. Goethe University, Frankfurt am Main, Germany.,Department of Plastic, Hand and Reconstructive Surgery, BG Trauma Center Frankfurt am Main gGmbH, Frankfurt am Main, Germany
| | - S Kynigopoulos
- Frankfurt Initiative for Regenerative Medicine, Experimental Orthopedics & Trauma Surgery, J.W. Goethe University, Frankfurt am Main, Germany
| | - M Eischen-Loges
- Frankfurt Initiative for Regenerative Medicine, Experimental Orthopedics & Trauma Surgery, J.W. Goethe University, Frankfurt am Main, Germany
| | - Z Han
- Frankfurt Initiative for Regenerative Medicine, Experimental Orthopedics & Trauma Surgery, J.W. Goethe University, Frankfurt am Main, Germany
| | - M B Bhavsar
- Frankfurt Initiative for Regenerative Medicine, Experimental Orthopedics & Trauma Surgery, J.W. Goethe University, Frankfurt am Main, Germany
| | - D Henrich
- Department of Trauma, Hand and Reconstructive Surgery, J.W. Goethe University, Frankfurt am Main, Germany
| | - L Leppik
- Frankfurt Initiative for Regenerative Medicine, Experimental Orthopedics & Trauma Surgery, J.W. Goethe University, Frankfurt am Main, Germany.
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18
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Dolan CP, Dawson LA, Muneoka K. Digit Tip Regeneration: Merging Regeneration Biology with Regenerative Medicine. Stem Cells Transl Med 2018; 7:262-270. [PMID: 29405625 PMCID: PMC5827737 DOI: 10.1002/sctm.17-0236] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 01/04/2018] [Indexed: 12/13/2022] Open
Abstract
Regeneration Biology is the study of organisms with endogenous regenerative abilities, whereas Regenerative Medicine focuses on engineering solutions for human injuries that do not regenerate. While the two fields are fundamentally different in their approach, there is an obvious interface involving mammalian regeneration models. The fingertip is the only part of the human limb that is regeneration-competent and the regenerating mouse digit tip has emerged as a model to study a clinically relevant regenerative response. In this article, we discuss how studies of digit tip regeneration have identified critical components of the regenerative response, and how an understanding of endogenous regeneration can lead to expanding the regenerative capabilities of nonregenerative amputation wounds. Such studies demonstrate that regeneration-incompetent wounds can respond to treatment with individual morphogenetic agents by initiating a multi-tissue response that culminates in structural regeneration. In addition, the healing process of nonregenerative wounds are found to cycle through nonresponsive, responsive and nonresponsive phases, and we call the responsive phase the Regeneration Window. We also find the responsiveness of mature healed amputation wounds can be reactivated by reinjury, thus nonregenerated wounds retain a potential for regeneration. We propose that regeneration-incompetent injuries possess dormant regenerative potential that can be activated by targeted treatment with specific morphogenetic agents. We believe that future Regenerative Medicine-based-therapies should be designed to promote, not replace, regenerative responses. Stem Cells Translational Medicine 2018;7:262-270.
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Affiliation(s)
- Connor P Dolan
- Department of Veterinary Physiology & Pharmacology, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Lindsay A Dawson
- Department of Veterinary Physiology & Pharmacology, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Ken Muneoka
- Department of Veterinary Physiology & Pharmacology, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, Texas, USA
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19
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The blastema and epimorphic regeneration in mammals. Dev Biol 2017; 433:190-199. [PMID: 29291973 DOI: 10.1016/j.ydbio.2017.08.007] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 07/28/2017] [Accepted: 08/04/2017] [Indexed: 01/02/2023]
Abstract
Studying regeneration in animals where and when it occurs is inherently interesting and a challenging research topic within developmental biology. Historically, vertebrate regeneration has been investigated in animals that display enhanced regenerative abilities and we have learned much from studying organ regeneration in amphibians and fish. From an applied perspective, while regeneration biologists will undoubtedly continue to study poikilothermic animals (i.e., amphibians and fish), studies focused on homeotherms (i.e., mammals and birds) are also necessary to advance regeneration biology. Emerging mammalian models of epimorphic regeneration are poised to help link regenerative biology and regenerative medicine. The regenerating rodent digit tip, which parallels human fingertip regeneration, and the regeneration of large circular defects through the ear pinna in spiny mice and rabbits, provide tractable, experimental systems where complex tissue structures are regrown through blastema formation and morphogenesis. Using these models as examples, we detail similarities and differences between the mammalian blastema and its classical counterpart to arrive at a broad working definition of a vertebrate regeneration blastema. This comparison leads us to conclude that regenerative failure is not related to the availability of regeneration-competent progenitor cells, but is most likely a function of the cellular response to the microenvironment that forms following traumatic injury. Recent studies demonstrating that targeted modification of this microenvironment can restrict or enhance regenerative capabilities in mammals helps provide a roadmap for eventually pushing the limits of human regeneration.
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20
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Simkin J, Seifert AW. Concise Review: Translating Regenerative Biology into Clinically Relevant Therapies: Are We on the Right Path? Stem Cells Transl Med 2017; 7:220-231. [PMID: 29271610 PMCID: PMC5788874 DOI: 10.1002/sctm.17-0213] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 11/29/2017] [Indexed: 02/06/2023] Open
Abstract
Despite approaches in regenerative medicine using stem cells, bio‐engineered scaffolds, and targeted drug delivery to enhance human tissue repair, clinicians remain unable to regenerate large‐scale, multi‐tissue defects in situ. The study of regenerative biology using mammalian models of complex tissue regeneration offers an opportunity to discover key factors that stimulate a regenerative rather than fibrotic response to injury. For example, although primates and rodents can regenerate their distal digit tips, they heal more proximal amputations with scar tissue. Rabbits and African spiny mice re‐grow tissue to fill large musculoskeletal defects through their ear pinna, while other mammals fail to regenerate identical defects and instead heal ear holes through fibrotic repair. This Review explores the utility of these comparative healing models using the spiny mouse ear pinna and the mouse digit tip to consider how mechanistic insight into reparative regeneration might serve to advance regenerative medicine. Specifically, we consider how inflammation and immunity, extracellular matrix composition, and controlled cell proliferation intersect to establish a pro‐regenerative microenvironment in response to injuries. Understanding how some mammals naturally regenerate complex tissue can provide a blueprint for how we might manipulate the injury microenvironment to enhance regenerative abilities in humans. Stem Cells Translational Medicine2018;7:220–231
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Affiliation(s)
- Jennifer Simkin
- Department of Biology, University of Kentucky, Lexington, Kentucky, USA
| | - Ashley W Seifert
- Department of Biology, University of Kentucky, Lexington, Kentucky, USA
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21
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Heber-Katz E. Oxygen, Metabolism, and Regeneration: Lessons from Mice. Trends Mol Med 2017; 23:1024-1036. [PMID: 28988849 DOI: 10.1016/j.molmed.2017.08.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 08/05/2017] [Accepted: 08/20/2017] [Indexed: 12/12/2022]
Abstract
The discovery that the Murphy Roths Large (MRL) mouse strain is a fully competent, epimorphic tissue regenerator, proved that the machinery of regeneration was preserved through evolution from hydra, to salamanders, to mammals. Such concepts have allowed translation of the biology of amphibians, and their ability to regenerate, to a mammalian context. We identified the ancient hypoxia-inducible factor (HIF)-1α pathway, operating through prolyl hydroxylase domain proteins (PHDs), as a central player in mouse regeneration. Thus, the possibility of targeting PHDs or other HIF-1α modifiers to effectively recreate the amphibian regenerative state has emerged. We posit that these regenerative pathways are critical in mammals. Moreover, the current approved use of PHD inhibitors in the clinic should allow fast-track translation from mouse studies to drug-based regenerative therapy in humans.
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Affiliation(s)
- Ellen Heber-Katz
- Laboratory of Regenerative Medicine, Lankenau Institute for Medical Research, Wynnewood, PA 19096, USA.
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22
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König D, Page L, Chassot B, Jaźwińska A. Dynamics of actinotrichia regeneration in the adult zebrafish fin. Dev Biol 2017; 433:416-432. [PMID: 28760345 DOI: 10.1016/j.ydbio.2017.07.024] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/25/2017] [Accepted: 07/27/2017] [Indexed: 01/21/2023]
Abstract
The skeleton of adult zebrafish fins comprises lepidotrichia, which are dermal bones of the rays, and actinotrichia, which are non-mineralized spicules at the distal margin of the appendage. Little is known about the regenerative dynamics of the actinotrichia-specific structural proteins called Actinodins. Here, we used immunofluorescence analysis to determine the contribution of two paralogous Actinodin proteins, And1/2, in regenerating fins. Both proteins were detected in the secretory organelles in the mesenchymal cells of the blastema, but only And1 was detected in the epithelial cells of the wound epithelium. The analysis of whole mount fins throughout the entire regenerative process and longitudinal sections revealed that And1-positive fibers are complementary to the lepidotrichia. The analysis of another longfin fish, a gain-of-function mutation in the potassium channel kcnk5b, revealed that the long-fin phenotype is associated with an extended size of actinotrichia during homeostasis and regeneration. Finally, we investigated the role of several signaling pathways in actinotrichia formation and maintenance. This revealed that the pulse-inhibition of either TGFβ/Activin-βA or FGF are sufficient to impair deposition of Actinodin during regeneration. Thus, the dynamic turnover of Actinodin during fin regeneration is regulated by multiple factors, including the osteoblasts, growth rate in a potassium channel mutant, and instructive signaling networks between the epithelium and the blastema of the regenerating fin.
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Affiliation(s)
- Désirée König
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland
| | - Lionel Page
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland
| | - Bérénice Chassot
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland
| | - Anna Jaźwińska
- Department of Biology, University of Fribourg, Chemin du Musée 10, 1700 Fribourg, Switzerland.
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23
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Marrero L, Simkin J, Sammarco M, Muneoka K. Fibroblast reticular cells engineer a blastema extracellular network during digit tip regeneration in mice. ACTA ACUST UNITED AC 2017; 4:69-84. [PMID: 28616246 PMCID: PMC5469731 DOI: 10.1002/reg2.75] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 01/27/2017] [Accepted: 02/24/2017] [Indexed: 12/11/2022]
Abstract
The regeneration blastema which forms following amputation of the mouse digit tip is composed of undifferentiated cells bound together by an organized network of fibers. A monoclonal antibody (ER‐TR7) that identifies extracellular matrix (ECM) fibers produced by fibroblast reticular cells during lymphoid organogenesis was used to characterize the ECM of the digit, the blastema, and the regenerate. Digit fibroblast reticular cells produce an ER‐TR7+ ECM network associated with different tissues and represent a subset of loose connective tissue fibroblasts. During blastema formation there is an upregulation of matrix production that returns to its pre‐existing level and anatomical pattern in the endpoint regenerate. Co‐localization studies demonstrate a strong spatial correlation between the ER‐TR7 antigen and collagen type III (COL3) in histological sections. ER‐TR7 and COL3 are co‐induced in cultured digit fibroblasts following treatment with tumor necrosis factor alpha and a lymphotoxin beta receptor agonist. These results provide an initial characterization of the ECM during digit regeneration and identify a subpopulation of fibroblasts involved in producing the blastema provisional matrix that is remodeled during the regeneration response.
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Affiliation(s)
- Luis Marrero
- Department of Cell and Molecular Biology Tulane University New Orleans LA 70118 USA.,Department of Medicine Louisiana State University Health Sciences Center New Orleans LA 70112 USA
| | - Jennifer Simkin
- Department of Cell and Molecular Biology Tulane University New Orleans LA 70118 USA
| | - Mimi Sammarco
- Department of Cell and Molecular Biology Tulane University New Orleans LA 70118 USA
| | - Ken Muneoka
- Department of Cell and Molecular Biology Tulane University New Orleans LA 70118 USA.,Department of Veterinary Physiology & Pharmacology Texas A&M University College Station TX7 7843 USA
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