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Zhang Y, Zeuthen C, Zhu C, Wu F, Mezzell AT, Whitlow TJ, Choo HJ, Vest KE. Pharyngeal pathology in a mouse model of oculopharyngeal muscular dystrophy is associated with impaired basal autophagy in myoblasts. Front Cell Dev Biol 2022; 10:986930. [PMID: 36313551 PMCID: PMC9614327 DOI: 10.3389/fcell.2022.986930] [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: 07/05/2022] [Accepted: 09/26/2022] [Indexed: 11/05/2023] Open
Abstract
Oculopharyngeal muscular dystrophy (OPMD) is a late-onset dominant disease that primarily affects craniofacial muscles. Despite the fact that the genetic cause of OPMD is known to be expansion mutations in the gene encoding the nuclear polyadenosine RNA binding protein PABPN1, the molecular mechanisms of pathology are unknown and no pharmacologic treatments are available. Due to the limited availability of patient tissues, several animal models have been employed to study the pathology of OPMD. However, none of these models have demonstrated functional deficits in the muscles of the pharynx, which are predominantly affected by OPMD. Here, we used a knock-in mouse model of OPMD, Pabpn1 +/A17 , that closely genocopies patients. In Pabpn1 +/A17 mice, we detected impaired pharyngeal muscle function, and impaired pharyngeal satellite cell proliferation and fusion. Molecular studies revealed that basal autophagy, which is required for normal satellite cell function, is higher in pharynx-derived myoblasts than in myoblasts derived from limb muscles. Interestingly, basal autophagy is impaired in cells derived from Pabpn1 +/A17 mice. Pabpn1 knockdown in pharyngeal myoblasts failed to recapitulate the autophagy defect detected in Pabpn1 +/A17 myoblasts suggesting that loss of PABPN1 function does not contribute to the basal autophagy defect. Taken together, these studies provide the first evidence for pharyngeal muscle and satellite cell pathology in a mouse model of OPMD and suggest that aberrant gain of PABPN1 function contributes to the craniofacial pathology in OPMD.
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Affiliation(s)
- Yu Zhang
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Christopher Zeuthen
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, United States
| | - Carol Zhu
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, United States
| | - Fang Wu
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, United States
| | - Allison T. Mezzell
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Thomas J. Whitlow
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Hyojung J. Choo
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, United States
| | - Katherine E. Vest
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, OH, United States
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Cheng X, Shi B, Li J. Distinct Embryonic Origin and Injury Response of Resident Stem Cells in Craniofacial Muscles. Front Physiol 2021; 12:690248. [PMID: 34276411 PMCID: PMC8281086 DOI: 10.3389/fphys.2021.690248] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 05/06/2021] [Indexed: 02/05/2023] Open
Abstract
Craniofacial muscles emerge as a developmental novelty during the evolution from invertebrates to vertebrates, facilitating diversified modes of predation, feeding and communication. In contrast to the well-studied limb muscles, knowledge about craniofacial muscle stem cell biology has only recently starts to be gathered. Craniofacial muscles are distinct from their counterparts in other regions in terms of both their embryonic origin and their injury response. Compared with somite-derived limb muscles, pharyngeal arch-derived craniofacial muscles demonstrate delayed myofiber reconstitution and prolonged fibrosis during repair. The regeneration of muscle is orchestrated by a blended source of stem/progenitor cells, including myogenic muscle satellite cells (MuSCs), mesenchymal fibro-adipogenic progenitors (FAPs) and other interstitial progenitors. Limb muscles host MuSCs of the Pax3 lineage, and FAPs from the mesoderm, while craniofacial muscles have MuSCs of the Mesp1 lineage and FAPs from the ectoderm-derived neural crest. Both in vivo and in vitro data revealed distinct patterns of proliferation and differentiation in these craniofacial muscle stem/progenitor cells. Additionally, the proportion of cells of different embryonic origins changes throughout postnatal development in the craniofacial muscles, creating a more dynamic niche environment than in other muscles. In-depth comparative studies of the stem cell biology of craniofacial and limb muscles might inspire the development of novel therapeutics to improve the management of myopathic diseases. Based on the most up-to-date literature, we delineated the pivotal cell populations regulating craniofacial muscle repair and identified clues that might elucidate the distinct embryonic origin and injury response in craniofacial muscle cells.
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Affiliation(s)
- Xu Cheng
- State Key Laboratory of Oral Diseases, Department of Oral and Maxillofacial Surgery, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Bing Shi
- State Key Laboratory of Oral Diseases, Department of Oral and Maxillofacial Surgery, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jingtao Li
- State Key Laboratory of Oral Diseases, Department of Oral and Maxillofacial Surgery, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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Kim HN, Kim JY. A Systematic Review of Oropharyngeal Dysphagia Models in Rodents. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:4987. [PMID: 34067192 PMCID: PMC8125817 DOI: 10.3390/ijerph18094987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 04/24/2021] [Accepted: 05/04/2021] [Indexed: 11/16/2022]
Abstract
Oropharyngeal dysphagia is a condition characterized by swallowing difficulty in the mouth and pharynx, which can be due to various factors. Animal models of oropharyngeal dysphagia are essential to confirm the cause-specific symptoms, pathological findings, and the effect of treatment. Recently, various animal models of dysphagia have been reported. The purpose of this review is to organize the rodent models of oropharyngeal dysphagia reported to date. The articles were obtained from Medline, Embase, and the Cochrane library, and selected following the PRISMA guideline. The animal models in which oropharyngeal dysphagia was induced in rats or mice were selected and classified based on the diseases causing oropharyngeal dysphagia. The animal used, method of inducing dysphagia, and screening methods and results were collected from the selected 37 articles. Various rodent models of oropharyngeal dysphagia provide distinctive information on atypical swallowing. Applying and analyzing the treatment in rodent models of dysphagia induced from various causes is an essential process to develop symptom-specific treatments. Therefore, the results of this study provide fundamental and important data for selecting appropriate animal models to study dysphagia.
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Affiliation(s)
- Han-Na Kim
- Department of Dental Hygiene, College of Health and Medical Sciences, Cheongju University, Cheongju 28503, Korea;
| | - Ji-Youn Kim
- Department of Dental Hygiene, College of Health Science, Gachon University, Incheon 21936, Korea
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Neuromuscular Specializations of the Human Hypopharyngeal Muscles. Dysphagia 2020; 36:769-785. [PMID: 33159539 DOI: 10.1007/s00455-020-10212-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 11/03/2020] [Indexed: 10/23/2022]
Abstract
The hypopharyngeal muscles in humans play a vital role in swallowing, speech, and respiration. Increasing evidence indicates that these muscles are specialized to perform life-sustaining upper aerodigestive functions. This review aims to provide current knowledge regarding the key structural, physiological, and biochemical features of the hypopharyngeal muscles, including innervation, contractile properties, histochemistry, biochemical properties, myosin heavy chain (MyHC) expression and regulation, and age-related alterations. These would clarify the unique neuromuscular specializations of the human hypopharyngeal muscles for a better understanding of the functions and pathological conditions of the pharynx and for the development of novel therapies to treat related upper airway disorders.
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Kim E, Wu F, Wu X, Choo HJ. Generation of craniofacial myogenic progenitor cells from human induced pluripotent stem cells for skeletal muscle tissue regeneration. Biomaterials 2020; 248:119995. [PMID: 32283390 PMCID: PMC7232788 DOI: 10.1016/j.biomaterials.2020.119995] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 03/13/2020] [Accepted: 03/20/2020] [Indexed: 12/18/2022]
Abstract
Craniofacial skeletal muscle is composed of approximately 60 muscles, which have critical functions including food uptake, eye movements and facial expressions. Although craniofacial muscles have significantly different embryonic origin, most current skeletal muscle differentiation protocols using human induced pluripotent stem cells (iPSCs) are based on somite-derived limb and trunk muscle developmental pathways. Since the lack of a protocol for craniofacial muscles is a significant gap in the iPSC-derived muscle field, we have developed an optimized protocol to generate craniofacial myogenic precursor cells (cMPCs) from human iPSCs by mimicking key signaling pathways during craniofacial embryonic myogenesis. At each different stage, human iPSC-derived cMPCs mirror the transcription factor expression profiles seen in their counterparts during embryo development. After the bi-potential cranial pharyngeal mesoderm is established, cells are committed to cranial skeletal muscle lineages with inhibition of cardiac lineages and are purified by flow cytometry. Furthermore, identities of Ipsc-derived cMPCs are verified with human primary myoblasts from craniofacial muscles using RNA sequencing. These data suggest that our new method could provide not only in vitro research tools to study muscle specificity of muscular dystrophy but also abundant and reliable cellular resources for tissue engineering to support craniofacial reconstruction surgery.
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Affiliation(s)
- Eunhye Kim
- Department of Cell Biology, School of Medcine, Emory University, Atlanta, GA, 30322, USA
| | - Fang Wu
- Department of Cell Biology, School of Medcine, Emory University, Atlanta, GA, 30322, USA
| | - Xuewen Wu
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, Emory University, Atlanta, GA, 30322, USA; Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital of Central South University, Changsha, Hunan, 410008, China
| | - Hyojung J Choo
- Department of Cell Biology, School of Medcine, Emory University, Atlanta, GA, 30322, USA.
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A study of chewing muscles: Age-related changes in type I collagen and matrix metalloproteinase-2 expression. Arch Oral Biol 2019; 109:104583. [PMID: 31706109 DOI: 10.1016/j.archoralbio.2019.104583] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 09/23/2019] [Accepted: 10/03/2019] [Indexed: 12/22/2022]
Abstract
OBJECTIVE In this study, the aim was to investigate the biochemical, physiological and histological changes that occur in masticatory muscles of the masticatory system with aging. DESIGN In this study, 14 BALB/c mice were used. Animals were divided into two equal groups of seven. Group I was organized as the group of young animals (n = 7) and Group II as the group of adult animals (n = 7). After routine histological follow-up was performed, the tissues were embedded in paraffin. 4-5 μm thick cross-sections were taken from paraffin-embedded tissues and they were stained with Haemotoxylin and Eosin Type I collagen and Matrix metalloproteinase-2 (MMP-2) immunohistochemically. RESULTS It was observed that there was a decrease and shrinking in blood vessels due to aging. In young mice, Type I collagen and MMP-2 immunoreactivity in the masseter muscle tissue showed low staining, while Type I collagen and MMP-2 immunoreactivity in the temporal muscle tissue showed moderate staining. Type I collagen and MMP-2 immunoreactivity were significantly higher in the masseter and temporal muscles of elderly mice (p = 0.001). In the H-score evaluation, MMP-2 immune reactivity was significantly lower in young mice than in older mice (p = 0.001). CONCLUSION It was determined that severe pain complications and functional losses are likely to occur with the increase of degeneration due to aging of masticator muscles.
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Elrabie Ahmed M, Bando H, Fuse S, Mostafa Abdelfattah H, Elrabie Ahmed M, Abdel-Kader Ahmed M, Tsujikawa T, Hisa Y. Differential isoform expression of SERCA and myosin heavy chain in hypopharyngeal muscles. ACTA ACUST UNITED AC 2019; 39:220-229. [PMID: 30933182 PMCID: PMC6734200 DOI: 10.14639/0392-100x-2185] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 06/12/2018] [Indexed: 11/25/2022]
Abstract
Composition of slow, fast and hybrid fibres of pharyngeal muscles,
associated with pharyngeal movements and regulation, has been rarely
studied. The present study aimed to identify expression of
sarcoplasmic reticulum Ca2+ ATPase (SERCA) and myosin heavy
chain (MHC) and hybrid isoforms in different pharyngeal muscles of
young and aged rats as well as humans. Isoform expression profiles of
SERCA, MHC and hybrid isoforms among six components of pharyngeal
muscle were immunohistochemically evaluated in rat and human. The
result showed that pharyngeal muscles predominantly expressed fast
fibres (SERCA1 and MHCII), whereas expression of slow fibres (SERCA2
and MHCI) was low, but different depending on muscle components. Inner
layer of pharyngeal muscles expressed more SERCA2 and hybrid fibres
than the outer layer. Pharyngeal muscles in aged rats showed increased
hybrid fibers and SERCA2. Human thyropharyngeus also showed a higher
portion of fast fibres compared to cricopharyngeus. Thus, in contrast
to abundance of fast fibres, slow and hybrid fibres are differentially
expressed depending on muscle components and layers as well as aging.
These results lead to further understanding of coordinated regulation
for speech and swallowing. The unique data presented in this study on
SERCA isoform expressions in both rats and human suggest an ability to
handle calcium changes according functional demands.
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Affiliation(s)
- Mohammed Elrabie Ahmed
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan.,Department of Otorhinolaryngology-Head and Neck Surgery, Sohag University Hospitals, Faculty of Medicine, Sohag University, Sohag, Egypt
| | - H Bando
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - S Fuse
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - H Mostafa Abdelfattah
- Department of Otorhinolaryngology-Head and Neck Surgery, Alexandria University, Alexandria, Egypt
| | - Mona Elrabie Ahmed
- Unit of Phoniatrics-Department of Otorhinolaryngology-Head and Neck Surgery, Sohag University, Egypt
| | - M Abdel-Kader Ahmed
- Department of Otorhinolaryngology-Head and Neck Surgery, Sohag University Hospitals, Faculty of Medicine, Sohag University, Sohag, Egypt
| | - T Tsujikawa
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Y Hisa
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto, Japan.,Department of Speech and Hearing Sciences and Disorders, Kyoto Gakuen University, Japan
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8
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Banerjee A, Phillips BL, Deng Q, Seyfried NT, Pavlath GK, Vest KE, Corbett AH. Proteomic analysis reveals that wildtype and alanine-expanded nuclear poly(A)-binding protein exhibit differential interactions in skeletal muscle. J Biol Chem 2019; 294:7360-7376. [PMID: 30837270 DOI: 10.1074/jbc.ra118.007287] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Revised: 02/19/2019] [Indexed: 12/22/2022] Open
Abstract
Oculopharyngeal muscular dystrophy (OPMD) is a late-onset, primarily autosomal dominant disease caused by a short GCN expansion in the PABPN1 (polyadenylate-binding protein nuclear 1) gene that results in an alanine expansion at the N terminus of the PABPN1 protein. Expression of alanine-expanded PABPN1 is linked to the formation of nuclear aggregates in tissues from individuals with OPMD. However, as with other nuclear aggregate-associated diseases, controversy exists over whether these aggregates are the direct cause of pathology. An emerging hypothesis is that a loss of PABPN1 function and/or aberrant protein interactions contribute to pathology in OPMD. Here, we present the first global proteomic analysis of the protein interactions of WT and alanine-expanded PABPN1 in skeletal muscle tissue. These data provide both insight into the function of PABPN1 in muscle and evidence that the alanine expansion alters the protein-protein interactions of PABPN1. We extended this analysis to demonstrate altered complex formation with and loss of function of TDP-43 (TAR DNA-binding protein 43), which we show interacts with alanine-expanded but not WT PABPN1. The results from our study support a model where altered protein interactions with alanine-expanded PABPN1 that lead to loss or gain of function could contribute to pathology in OPMD.
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Affiliation(s)
| | - Brittany L Phillips
- From the Department of Biology and.,the Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, Georgia 30322
| | - Quidong Deng
- the Department of Biochemistry, Center for Neurodegenerative Diseases and
| | | | - Grace K Pavlath
- the Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia 30322, and
| | - Katherine E Vest
- the Department of Molecular Genetics, Biochemistry & Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
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9
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Kletzien H, Cullins MJ, Connor NP. Age-related alterations in swallowing biomechanics. Exp Gerontol 2019; 118:45-50. [PMID: 30633957 DOI: 10.1016/j.exger.2019.01.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 12/14/2018] [Accepted: 01/06/2019] [Indexed: 11/26/2022]
Abstract
BACKGROUND Aging rodent models allow for the discovery of underlying mechanisms of cranial muscle dysfunction. Methods are needed to allow quantification of complex, multivariate biomechanical movements during swallowing. Videofluoroscopic swallow studies (VSS) are the standard of care in assessment of swallowing disorders in patients and validated quantitative, kinematic, and morphometric analysis methods have been developed. Our purpose was to adapt validated morphometric techniques to the rodent to computationally analyze swallowing dysfunction in the aging rodent. METHODS VSS, quantitative analyses (bolus area, bolus velocity, mastication rate) and a rodent specific multivariate, morphometric computational analysis of swallowing biomechanics were performed on 20 swallows from 5 young adult and 5 old Fischer 344/Brown Norway rats. Eight anatomical landmarks were used to track the relative change in position of skeletal levers (cranial base, vertebral column, mandible) and soft tissue landmarks (upper esophageal sphincter, base of tongue). RESULTS Bolus area significantly increased and mastication rate significantly decreased with age. Aging accounted for 77.1% of the variance in swallow biomechanics, and 18.7% of the variance was associated with swallow phase (oral vs pharyngeal). Post hoc analyses identified age-related alterations in tongue base retraction, mastication, and head posture during the swallow. CONCLUSION Geometric morphometric analysis of rodent swallows suggests that swallow biomechanics are altered with age. When used in combination with biological assays of age-related adaptations in neuromuscular systems, this multivariate analysis may increase our understanding of underlying musculoskeletal dysfunction that contributes to swallowing disorders with aging.
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Affiliation(s)
- Heidi Kletzien
- Division of Otolaryngology-Head and Neck Cancer, Department of Surgery, University of Wisconsin School of Medicine and Public Health, United States of America; Department of Biomedical Engineering, University of Wisconsin-Madison, United States of America.
| | - Miranda J Cullins
- Division of Otolaryngology-Head and Neck Cancer, Department of Surgery, University of Wisconsin School of Medicine and Public Health, United States of America
| | - Nadine P Connor
- Division of Otolaryngology-Head and Neck Cancer, Department of Surgery, University of Wisconsin School of Medicine and Public Health, United States of America; Department of Biomedical Engineering, University of Wisconsin-Madison, United States of America; Department of Communication Sciences and Disorders, University of Wisconsin-Madison, United States of America
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10
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Vest KE, Phillips BL, Banerjee A, Apponi LH, Dammer EB, Xu W, Zheng D, Yu J, Tian B, Pavlath GK, Corbett AH. Novel mouse models of oculopharyngeal muscular dystrophy (OPMD) reveal early onset mitochondrial defects and suggest loss of PABPN1 may contribute to pathology. Hum Mol Genet 2017; 26:3235-3252. [PMID: 28575395 PMCID: PMC5886286 DOI: 10.1093/hmg/ddx206] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 05/14/2017] [Accepted: 05/23/2017] [Indexed: 01/09/2023] Open
Abstract
Oculopharyngeal muscular dystrophy (OPMD) is a late onset disease caused by polyalanine expansion in the poly(A) binding protein nuclear 1 (PABPN1). Several mouse models have been generated to study OPMD; however, most of these models have employed transgenic overexpression of alanine-expanded PABPN1. These models do not recapitulate the OPMD patient genotype and PABPN1 overexpression could confound molecular phenotypes. We have developed a knock-in mouse model of OPMD (Pabpn1+/A17) that contains one alanine-expanded Pabpn1 allele under the control of the native promoter and one wild-type Pabpn1 allele. This mouse is the closest available genocopy of OPMD patients. We show that Pabpn1+/A17 mice have a mild myopathic phenotype in adult and aged animals. We examined early molecular and biochemical phenotypes associated with expressing native levels of A17-PABPN1 and detected shorter poly(A) tails, modest changes in poly(A) signal (PAS) usage, and evidence of mitochondrial damage in these mice. Recent studies have suggested that a loss of PABPN1 function could contribute to muscle pathology in OPMD. To investigate a loss of function model of pathology, we generated a heterozygous Pabpn1 knock-out mouse model (Pabpn1+/Δ). Like the Pabpn1+/A17 mice, Pabpn1+/Δ mice have mild histologic defects, shorter poly(A) tails, and evidence of mitochondrial damage. However, the phenotypes detected in Pabpn1+/Δ mice only partially overlap with those detected in Pabpn1+/A17 mice. These results suggest that loss of PABPN1 function could contribute to but may not completely explain the pathology detected in Pabpn1+/A17 mice.
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Affiliation(s)
- Katherine E. Vest
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, USA
- Department of Biology, Emory University, Atlanta, GA, USA
| | - Brittany L. Phillips
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, USA
- Department of Biology, Emory University, Atlanta, GA, USA
| | - Ayan Banerjee
- Department of Biology, Emory University, Atlanta, GA, USA
| | - Luciano H. Apponi
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, USA
| | - Eric B. Dammer
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Weiting Xu
- Department of Microbiology, Biochemistry, and Molecular Genetics, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Dinghai Zheng
- Department of Microbiology, Biochemistry, and Molecular Genetics, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Julia Yu
- Department of Biology, Emory University, Atlanta, GA, USA
| | - Bin Tian
- Department of Microbiology, Biochemistry, and Molecular Genetics, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Grace K. Pavlath
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, USA
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11
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Randolph ME, Phillips BL, Choo HJ, Vest KE, Vera Y, Pavlath GK. Pharyngeal Satellite Cells Undergo Myogenesis Under Basal Conditions and Are Required for Pharyngeal Muscle Maintenance. Stem Cells 2016; 33:3581-95. [PMID: 26178867 DOI: 10.1002/stem.2098] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 05/15/2015] [Accepted: 06/01/2015] [Indexed: 12/19/2022]
Abstract
The pharyngeal muscles of the nasal, oral, and laryngeal pharynxes are required for swallowing. Pharyngeal muscles are preferentially affected in some muscular dystrophies yet spared in others. Muscle stem cells, called satellite cells, may be critical factors in the development of pharyngeal muscle disorders; however, very little is known about pharyngeal satellite cells (PSC) and their role in pharyngeal muscles. We show that PSC are distinct from the commonly studied hindlimb satellite cells both transcriptionally and biologically. Under basal conditions PSC proliferate, progress through myogenesis, and fuse with pharyngeal myofibers. Furthermore, PSC exhibit biologic differences dependent on anatomic location in the pharynx. Importantly, PSC are required to maintain myofiber size and myonuclear number in pharyngeal myofibers. Together, these results demonstrate that PSC are critical for pharyngeal muscle maintenance and suggest that satellite cell impairment could contribute to pharyngeal muscle pathology associated with various muscular dystrophies and aging.
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Affiliation(s)
| | | | - Hyo-Jung Choo
- Department of Pharmacology, Emory University, Atlanta, Georgia, USA
| | - Katherine E Vest
- Department of Pharmacology, Emory University, Atlanta, Georgia, USA
| | - Yandery Vera
- Department of Pharmacology, Emory University, Atlanta, Georgia, USA
| | - Grace K Pavlath
- Department of Pharmacology, Emory University, Atlanta, Georgia, USA
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12
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Randolph ME, Pavlath GK. A muscle stem cell for every muscle: variability of satellite cell biology among different muscle groups. Front Aging Neurosci 2015; 7:190. [PMID: 26500547 PMCID: PMC4595652 DOI: 10.3389/fnagi.2015.00190] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 09/21/2015] [Indexed: 12/22/2022] Open
Abstract
The human body contains approximately 640 individual skeletal muscles. Despite the fact that all of these muscles are composed of striated muscle tissue, the biology of these muscles and their associated muscle stem cell populations are quite diverse. Skeletal muscles are affected differentially by various muscular dystrophies (MDs), such that certain genetic mutations specifically alter muscle function in only a subset of muscles. Additionally, defective muscle stem cells have been implicated in the pathology of some MDs. The biology of muscle stem cells varies depending on the muscles with which they are associated. Here we review the biology of skeletal muscle stem cell populations of eight different muscle groups. Understanding the biological variation of skeletal muscles and their resident stem cells could provide valuable insight into mechanisms underlying the susceptibility of certain muscles to myopathic disease.
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