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Gunning JA, Limesand KH. Chronic Phenotypes Underlying Radiation-Induced Salivary Gland Dysfunction. J Dent Res 2024:220345241252396. [PMID: 38808518 DOI: 10.1177/00220345241252396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2024] Open
Abstract
Head and neck cancer (HNC) is the sixth most diagnosed cancer, and treatment typically consists of surgical removal of the tumor followed by ionizing radiation (IR). While excellent at controlling tumor growth, IR often damages salivary glands due to their proximity to common tumor sites. Radiation damage to salivary glands results in loss of secretory function, causing severe and chronic reductions in salivary flow. This leads to the patient-reported sensation of dry mouth, termed xerostomia, which significantly reduces quality of life for HNC patients and survivors. The mechanisms underlying salivary gland damage remain elusive, and therefore, treatment options are scarce. Available therapies provide temporary symptom relief, but there is no standard of care for permanent restoration of function. There is a significant gap in understanding the chronic mechanistic responses to radiation as well as treatments that can be given in the months to years following cessation of treatment. HNC cases are steadily rising; particularly, the number of young patients diagnosed with nonfatal human papillomavirus + HNC continues to increase. The growing number of HNC diagnoses and improved prognoses results in more people living with xerostomia, which highlights the mounting need for restorative treatments. Mechanisms underlying chronic damage include decreases in acinar differentiation markers, increases in acinar cell proliferation, immune and inflammatory dysregulation, and metabolic changes including increases in amino acids and reductions in glycolysis and oxidative phosphorylation, fibrosis, and dysregulated neuronal responses. Currently, promising treatment options include adenoviral gene transfers and stem cell therapy. Thus, this review describes in depth known mechanisms contributing to chronic damage and discusses therapeutic advances in treating chronically damaged glands. Understanding the chronic response to radiation offers potential in development of new therapeutics to reverse salivary gland damage and improve the quality of life of HNC survivors.
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Affiliation(s)
- J A Gunning
- Department of Nutritional Sciences, The University of Arizona, Tucson, AZ, USA
| | - K H Limesand
- Department of Nutritional Sciences, The University of Arizona, Tucson, AZ, USA
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2
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Xiao XY, Zhang NN, Long YZ, Huang GL. Repair mechanism of radiation-induced salivary gland injury by hypoxia-pretreated human urine-derived stem cell exosomes. Oral Dis 2024; 30:1234-1241. [PMID: 36546840 DOI: 10.1111/odi.14476] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 12/07/2022] [Accepted: 12/12/2022] [Indexed: 12/24/2022]
Abstract
OBJECTIVE To explore the protective effect of human urine-derived stem cell exosomes (hUSC-Exos) on radiation-induced salivary gland (SG) injuries in Sprague Dawley rats. METHODS Fresh adult urine was collected, and primary hUSCs were isolated and identified. The hUSCs were hypoxia-pretreated with 1% oxygen for 24 h and then transferred to a normoxic culture environment for 24 h. The hUSC-Exos were collected and identified for exosomes. A radiation-induced injury model was established in the rats, and exosomes were introduced by local injection in the SG and tail vein. The submandibular gland was excised for morphological observation 1 week later. Immunohistochemical detection of the glandular tissue was conducted by α-smooth muscle actin (a-SMA), stem cell growth factor receptor (c-Kit) staining, and periodic acid-Schiff staining. Qualitative polymerase chain reaction and western blot analysis were adopted to detect the gene and protein expression of Wnt3a, GSK3β, and Axin. RESULTS In both the normoxic and hypoxic hUSC-Exo groups, microvesicular structures with bilayer membranes of approximately 80 nm in diameter were detected, and the expressions of CD9 and CD63 were detected by nanoflow cytometry. Compared with the control group, in the radiation-induced injury model group, the expression of a-SMA was significantly higher, the expression of c-Kit was significantly lower, and the expressions of Wnt3a, GSK3β, and Axin were significantly upregulated; the differences were statistically significant (p < 0.05). Compared with the model group, in the normoxic and hypoxic hUSC-Exo groups, the expression of a-SMA was significantly decreased, the expression of c-Kit was significantly increased, and the expressions of Wnt3a, GSK3β, and Axin were significantly upregulated; the differences were statistically significant (p < 0.05). CONCLUSION Hypoxia-pretreated hUSC-Exos could repair radiation-induced SG injuries by activating the Wnt3a/GSK3β pathway to suppress the expressions of a-SMA and c-Kit.
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Affiliation(s)
| | - Ni-Ni Zhang
- Department of Dentofacial Surgery, Affiliated Stomatological Hospital of Zunyi Medical University, Zunyi, China
| | - Yuan-Zhu Long
- School Stomatol, Key Lab Oral Disease Research, Zunyi Medical University, Zunyi, China
| | - Gui-Lin Huang
- Department of Dentofacial Surgery, Affiliated Stomatological Hospital of Zunyi Medical University, Zunyi, China
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3
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Gunning JA, Gilman KE, Zúñiga TM, Simpson RJ, Limesand KH. Parotid glands have a dysregulated immune response following radiation therapy. PLoS One 2024; 19:e0297387. [PMID: 38470874 PMCID: PMC10931461 DOI: 10.1371/journal.pone.0297387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 01/04/2024] [Indexed: 03/14/2024] Open
Abstract
Head and neck cancer treatment often consists of surgical resection of the tumor followed by ionizing radiation (IR), which can damage surrounding tissues and cause adverse side effects. The underlying mechanisms of radiation-induced salivary gland dysfunction are not fully understood, and treatment options are scarce and ineffective. The wound healing process is a necessary response to tissue injury, and broadly consists of inflammatory, proliferative, and redifferentiation phases with immune cells playing key roles in all three phases. In this study, select immune cells were phenotyped and quantified, and certain cytokine and chemokine concentrations were measured in mouse parotid glands after IR. Further, we used a model where glandular function is restored to assess the immune phenotype in a regenerative response. These data suggest that irradiated parotid tissue does not progress through a typical inflammatory response observed in wounds that heal. Specifically, total immune cells (CD45+) decrease at days 2 and 5 following IR, macrophages (F4/80+CD11b+) decrease at day 2 and 5 and increase at day 30, while neutrophils (Ly6G+CD11b+) significantly increase at day 30 following IR. Additionally, radiation treatment reduces CD3- cells at all time points, significantly increases CD3+/CD4+CD8+ double positive cells, and significantly reduces CD3+/CD4-CD8- double negative cells at day 30 after IR. Previous data indicate that post-IR treatment with IGF-1 restores salivary gland function at day 30, and IGF-1 injections attenuate the increase in macrophages, neutrophils, and CD4+CD8+ T cells observed at day 30 following IR. Taken together, these data indicate that parotid salivary tissue exhibits a dysregulated immune response following radiation treatment which may contribute to chronic loss of function phenotype in head and neck cancer survivors.
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Affiliation(s)
- Jordan A. Gunning
- Department of Nutritional Sciences, The University of Arizona, Tucson, Arizona, United States of America
| | - Kristy E. Gilman
- Department of Nutritional Sciences, The University of Arizona, Tucson, Arizona, United States of America
| | - Tiffany M. Zúñiga
- Department of Nutritional Sciences, The University of Arizona, Tucson, Arizona, United States of America
- Department of Immunology and Microbiology, Aurora, Colorado, United States of America
| | - Richard J. Simpson
- Department of Nutritional Sciences, The University of Arizona, Tucson, Arizona, United States of America
| | - Kirsten H. Limesand
- Department of Nutritional Sciences, The University of Arizona, Tucson, Arizona, United States of America
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4
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Buss LG, Rheinheimer BA, Limesand KH. Radiation-induced changes in energy metabolism result in mitochondrial dysfunction in salivary glands. Sci Rep 2024; 14:845. [PMID: 38191641 PMCID: PMC10774336 DOI: 10.1038/s41598-023-50877-9] [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: 06/29/2023] [Accepted: 12/27/2023] [Indexed: 01/10/2024] Open
Abstract
Salivary glands are indirectly damaged during radiotherapy for head and neck cancer, resulting in acute and chronic hyposalivation. Current treatments for radiation-induced hyposalivation do not permanently restore function to the gland; therefore, more mechanistic understanding of the damage response is needed to identify therapeutic targets for lasting restoration. Energy metabolism reprogramming has been observed in cancer and wound healing models to provide necessary fuel for cell proliferation; however, there is limited understanding of alterations in energy metabolism reprogramming in tissues that fail to heal. We measured extracellular acidification and oxygen consumption rates, assessed mitochondrial DNA copy number, and tested fuel dependency of irradiated primary salivary acinar cells. Radiation treatment leads to increases in glycolytic flux, oxidative phosphorylation, and ATP production rate at acute and intermediate time points. In contrast, at chronic radiation time points there is a significant decrease in glycolytic flux, oxidative phosphorylation, and ATP production rate. Irradiated salivary glands exhibit significant decreases in spare respiratory capacity and increases in mitochondrial DNA copy number at days 5 and 30 post-treatment, suggesting a mitochondrial dysfunction phenotype. These results elucidate kinetic changes in energy metabolism reprogramming of irradiated salivary glands that may underscore the chronic loss of function phenotype.
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Affiliation(s)
- Lauren G Buss
- School of Nutritional Sciences and Wellness, University of Arizona, 1177 E 4th St, Shantz Building Room 421, Tucson, AZ, USA
| | - Brenna A Rheinheimer
- School of Nutritional Sciences and Wellness, University of Arizona, 1177 E 4th St, Shantz Building Room 421, Tucson, AZ, USA
| | - Kirsten H Limesand
- School of Nutritional Sciences and Wellness, University of Arizona, 1177 E 4th St, Shantz Building Room 421, Tucson, AZ, USA.
- University of Arizona Cancer Center, Tucson, AZ, USA.
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5
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Buss LG, Rheinheimer BA, Limesand KH. Radiation-Induced Changes in Energy Metabolism Result in Mitochondrial Dysfunction in Salivary Glands. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.27.568879. [PMID: 38077038 PMCID: PMC10705263 DOI: 10.1101/2023.11.27.568879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2024]
Abstract
Salivary glands are indirectly damaged during radiotherapy for head and neck cancer, resulting in acute and chronic hyposalivation. Current treatments for radiation-induced hyposalivation do not permanently restore function to the gland; therefore, more mechanistic understanding of the damage response is needed to identify therapeutic targets for lasting restoration. Energy metabolism reprogramming has been observed in cancer and wound healing models to provide necessary fuel for cell proliferation; however, there is limited understanding of alterations in energy metabolism reprogramming in tissues that fail to heal. We measured extracellular acidification and oxygen consumption rates, assessed mitochondrial DNA copy number, and tested fuel dependency of irradiated primary salivary acinar cells. Radiation treatment leads to increases in glycolytic flux, oxidative phosphorylation, and ATP production rate at acute and intermediate time points. In contrast, at chronic radiation time points there is a significant decrease in glycolytic flux, oxidative phosphorylation, and ATP production rate. Irradiated salivary glands exhibit significant decreases in spare respiratory capacity and increases in mitochondrial DNA copy number at days 5 and 30 post-treatment, suggesting a mitochondrial dysfunction phenotype. These results elucidate kinetic changes in energy metabolism reprogramming of irradiated salivary glands that may underscore the chronic loss of function phenotype.
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6
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Buss LG, De Oliveira Pessoa D, Snider JM, Padi M, Martinez JA, Limesand KH. Metabolomics analysis of pathways underlying radiation-induced salivary gland dysfunction stages. PLoS One 2023; 18:e0294355. [PMID: 37983277 PMCID: PMC10659204 DOI: 10.1371/journal.pone.0294355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 10/30/2023] [Indexed: 11/22/2023] Open
Abstract
Salivary gland hypofunction is an adverse side effect associated with radiotherapy for head and neck cancer patients. This study delineated metabolic changes at acute, intermediate, and chronic radiation damage response stages in mouse salivary glands following a single 5 Gy dose. Ultra-high performance liquid chromatography-mass spectrometry was performed on parotid salivary gland tissue collected at 3, 14, and 30 days following radiation (IR). Pathway enrichment analysis, network analysis based on metabolite structural similarity, and network analysis based on metabolite abundance correlations were used to incorporate both metabolite levels and structural annotation. The greatest number of enriched pathways are observed at 3 days and the lowest at 30 days following radiation. Amino acid metabolism pathways, glutathione metabolism, and central carbon metabolism in cancer are enriched at all radiation time points across different analytical methods. This study suggests that glutathione and central carbon metabolism in cancer may be important pathways in the unresolved effect of radiation treatment.
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Affiliation(s)
- Lauren G Buss
- School of Nutritional Sciences and Wellness, University of Arizona, Tucson, AZ, United States of America
| | - Diogo De Oliveira Pessoa
- Biostatistics and Bioinformatics Shared Resource, Arizona Cancer Center, University of Arizona, Tucson, AZ, United States of America
| | - Justin M Snider
- School of Nutritional Sciences and Wellness, University of Arizona, Tucson, AZ, United States of America
- University of Arizona Cancer Center, Tucson, AZ, United States of America
| | - Megha Padi
- Biostatistics and Bioinformatics Shared Resource, Arizona Cancer Center, University of Arizona, Tucson, AZ, United States of America
- University of Arizona Cancer Center, Tucson, AZ, United States of America
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, United States of America
| | - Jessica A Martinez
- School of Nutritional Sciences and Wellness, University of Arizona, Tucson, AZ, United States of America
- University of Arizona Cancer Center, Tucson, AZ, United States of America
| | - Kirsten H Limesand
- School of Nutritional Sciences and Wellness, University of Arizona, Tucson, AZ, United States of America
- University of Arizona Cancer Center, Tucson, AZ, United States of America
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7
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Nagesh PKB, Monette S, Shamu T, Giralt S, Jean SCS, Zhang Z, Fuks Z, Kolesnick R. Anti-ceramide Single-Chain Variable Fragment Mitigates Gastrointestinal-Acute Radiation Syndrome and Improves Marrow Reconstitution, Rendering Near-Normal 90-Day Autopsies. Int J Radiat Oncol Biol Phys 2023:S0360-3016(23)07728-3. [PMID: 37815783 PMCID: PMC10947531 DOI: 10.1016/j.ijrobp.2023.07.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 07/18/2023] [Accepted: 07/29/2023] [Indexed: 10/11/2023]
Abstract
PURPOSE After September 11, 2001, nuclear threat prompted government agencies to develop medical countermeasures to mitigate two syndromes, the hematopoietic-acute radiation syndrome (H-ARS) and the higher-dose gastrointestinal-acute radiation syndrome (GI-ARS), both lethal within weeks. While repurposing leukemia drugs that enhance bone marrow repopulation successfully treats H-ARS, no mitigator potentially deliverable under mass casualty conditions preserves the GI tract. We recently reported that anti-ceramide single-chain variable fragment (scFv) mitigates GI-ARS lethality, abrogating ongoing small intestinal endothelial apoptosis to rescue Lgr5+ stem cells. Here, we examine long-term consequences of prevention of acute GI-ARS lethality. METHODS AND MATERIALS For these studies, C57BL/6J male mice were treated with 15 Gy whole body irradiation, the 90% GI-ARS lethal dose for this mouse strain. RESULTS Mice irradiated with 15 Gy alone or with 15 Gy + bone marrow transplantation (BMT) or anti-ceramide scFv, succumb to an ARS within 8 to 10 days. Autopsies reveal only mice receiving anti-ceramide scFv at 24 hours post-whole body irradiation display small intestinal rescue. No marrow reconstitution occurs in any group with attendant undetectable circulating blood elements. Mice receiving 15 Gy + BMT + scFv, however, normalize blood counts by day 12, suggesting that scFv also improves marrow reconstitution, a concept for which we provide experimental support. We show that at 14 Gy, the upper limit dose for H-ARS lethality before transition to GI-ARS lethality, anti-ceramide scFv markedly improves marrow take, reducing the quantity of marrow-conferring survival by more than 3-fold. Consistent with these findings, mice receiving 15 Gy + BMT + scFv exhibit prolonged survival. At day 90, before sacrifice, they display normal appearance, behavior, and serum biochemistries, and surprisingly, at full autopsy, near-normal physiology in all 42 tissues examined. CONCLUSIONS Anti-ceramide scFv mitigates GI-ARS lethality and improves marrow reconstitution rendering prolonged survival with near normal autopsies.
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Affiliation(s)
- Prashanth K B Nagesh
- Laboratory of Signal Transduction, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Sebastien Monette
- Laboratory of Comparative Pathology, Rockefeller University, Weill Cornell Medicine and Memorial Sloan Kettering Cancer Center, New York, New York
| | - Tambudzai Shamu
- Laboratory of Signal Transduction, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Sergio Giralt
- Division of Hematologic Malignancies, Adult BMT Service, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Samantha C St Jean
- Laboratory of Comparative Pathology, Rockefeller University, Weill Cornell Medicine and Memorial Sloan Kettering Cancer Center, New York, New York
| | - Zhigang Zhang
- Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Zvi Fuks
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York; Champalimaud Center, Lisbon, Portugal
| | - Richard Kolesnick
- Laboratory of Signal Transduction, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York.
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8
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Marinkovic M, Tran ON, Wang H, Abdul-Azees P, Dean DD, Chen XD, Yeh CK. Autologous mesenchymal stem cells offer a new paradigm for salivary gland regeneration. Int J Oral Sci 2023; 15:18. [PMID: 37165024 PMCID: PMC10172302 DOI: 10.1038/s41368-023-00224-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 02/20/2023] [Accepted: 03/29/2023] [Indexed: 05/12/2023] Open
Abstract
Salivary gland (SG) dysfunction, due to radiotherapy, disease, or aging, is a clinical manifestation that has the potential to cause severe oral and/or systemic diseases and compromise quality of life. Currently, the standard-of-care for this condition remains palliative. A variety of approaches have been employed to restore saliva production, but they have largely failed due to damage to both secretory cells and the extracellular matrix (niche). Transplantation of allogeneic cells from healthy donors has been suggested as a potential solution, but no definitive population of SG stem cells, capable of regenerating the gland, has been identified. Alternatively, mesenchymal stem cells (MSCs) are abundant, well characterized, and during SG development/homeostasis engage in signaling crosstalk with the SG epithelium. Further, the trans-differentiation potential of these cells and their ability to regenerate SG tissues have been demonstrated. However, recent findings suggest that the "immuno-privileged" status of allogeneic adult MSCs may not reflect their status post-transplantation. In contrast, autologous MSCs can be recovered from healthy tissues and do not present a challenge to the recipient's immune system. With recent advances in our ability to expand MSCs in vitro on tissue-specific matrices, autologous MSCs may offer a new therapeutic paradigm for restoration of SG function.
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Affiliation(s)
- Milos Marinkovic
- Department of Comprehensive Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Research Service, South Texas Veterans Health Care System, San Antonio, TX, USA
| | - Olivia N Tran
- Department of Comprehensive Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Hanzhou Wang
- Department of Comprehensive Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Parveez Abdul-Azees
- Department of Comprehensive Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Research Service, South Texas Veterans Health Care System, San Antonio, TX, USA
| | - David D Dean
- Department of Comprehensive Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Department of Biomedical Engineering, University of Texas at San Antonio, San Antonio, TX, USA
| | - Xiao-Dong Chen
- Department of Comprehensive Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
- Research Service, South Texas Veterans Health Care System, San Antonio, TX, USA.
- Department of Biomedical Engineering, University of Texas at San Antonio, San Antonio, TX, USA.
| | - Chih-Ko Yeh
- Department of Comprehensive Dentistry, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
- Geriatric Research, Education and Clinical Center, South Texas Veterans Health Care System, San Antonio, TX, USA.
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9
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Meyer R, Gilman K, Rheinheimer B, Meeks L, Limesand K. AMPK Activation Restores Salivary Function Following Radiation Treatment. J Dent Res 2023; 102:546-554. [PMID: 36726289 PMCID: PMC10249004 DOI: 10.1177/00220345221148983] [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] [Indexed: 02/03/2023] Open
Abstract
Head and neck cancers represent a significant portion of cancer diagnoses, with head and neck cancer incidence increasing in some parts of the world. Typical treatment of early-stage head and neck cancers includes either surgery or radiotherapy; however, advanced cases often require surgery followed by radiation and chemotherapy. Salivary gland damage following radiotherapy leads to severe and chronic hypofunction with decreased salivary output, xerostomia, impaired ability to chew and swallow, increased risk of developing oral mucositis, and malnutrition. There is currently no standard of care for radiation-induced salivary gland dysfunction, and treatment is often limited to palliative treatment that provides only temporary relief. Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is an enzyme that activates catabolic processes and has been shown to influence the cell cycle, proliferation, and autophagy. In the present study, we found that radiation (IR) treatment decreases tissue levels of phosphorylated AMPK following radiation and decreases intracellular NAD+ and AMP while increasing intracellular adenosine triphosphate. Furthermore, expression of sirtuin 1 (SIRT1) and nicotinamide phosphoribosyl transferase (NAMPT) was lower 5 d following IR. Treatment with AMPK activators, 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) and metformin, attenuated compensatory proliferation (days 6, 7, and 30) following IR and reversed chronic (day 30) salivary gland dysfunction post-IR. In addition, treatment with metformin or AICAR increased markers of apical/basolateral polarity (phosphorylated aPKCζT560-positive area) and differentiation (amylase-positive area) within irradiated parotid glands to levels similar to untreated controls. Taken together, these data suggest that AMPK may be a novel therapeutic target for treatment of radiation-induced salivary damage.
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Affiliation(s)
- R.K. Meyer
- School of Nutritional Sciences and Wellness,
University of Arizona, Tucson, AZ, USA
| | - K.E. Gilman
- School of Nutritional Sciences and Wellness,
University of Arizona, Tucson, AZ, USA
| | - B.A. Rheinheimer
- School of Nutritional Sciences and Wellness,
University of Arizona, Tucson, AZ, USA
| | - L. Meeks
- School of Nutritional Sciences and Wellness,
University of Arizona, Tucson, AZ, USA
| | - K.H. Limesand
- School of Nutritional Sciences and Wellness,
University of Arizona, Tucson, AZ, USA
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10
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Chibly AM, Patel VN, Aure MH, Pasquale MC, Martin GE, Ghannam M, Andrade J, Denegre NG, Simpson C, Goldstein DP, Liu FF, Lombaert IMA, Hoffman MP. Neurotrophin signaling is a central mechanism of salivary dysfunction after irradiation that disrupts myoepithelial cells. NPJ Regen Med 2023; 8:17. [PMID: 36966175 PMCID: PMC10039923 DOI: 10.1038/s41536-023-00290-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 02/27/2023] [Indexed: 03/27/2023] Open
Abstract
The mechanisms that prevent regeneration of irradiated (IR) salivary glands remain elusive. Bulk RNAseq of IR versus non-IR human salivary glands showed that neurotrophin signaling is highly disrupted post-radiation. Neurotrophin receptors (NTRs) were significantly upregulated in myoepithelial cells (MECs) post-IR, and single cell RNAseq revealed that MECs pericytes, and duct cells are the main sources of neurotrophin ligands. Using two ex vivo models, we show that nerve growth factor (NGF) induces expression of MEC genes during development, and upregulation of NTRs in adult MECs is associated with stress-induced plasticity and morphological abnormalities in IR human glands. As MECs are epithelial progenitors after gland damage and are required for proper acinar cell contraction and secretion, we propose that MEC-specific upregulation of NTRs post-IR disrupts MEC differentiation and potentially impedes the ability of the gland to regenerate.
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Affiliation(s)
- Alejandro M Chibly
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Vaishali N Patel
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Marit H Aure
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Mary C Pasquale
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Gemma E Martin
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Mousa Ghannam
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Julianne Andrade
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Noah G Denegre
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Colleen Simpson
- Department of Otolaryngology-Head & Neck Surgery, Princess Margaret Cancer Center, Toronto, ON, M5G 2C4, Canada
| | - David P Goldstein
- Department of Otolaryngology-Head & Neck Surgery, Princess Margaret Cancer Center, Toronto, ON, M5G 2C4, Canada
| | - Fei-Fei Liu
- Department of Radiation Oncology, Princess Margaret Cancer Center, Toronto, ON, M5G 2M9, Canada
| | - Isabelle M A Lombaert
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
- Department of Biologic and Material Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI, 48109, USA
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Matthew P Hoffman
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA.
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11
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Diagnosis, Prevention, and Treatment of Radiotherapy-Induced Xerostomia: A Review. JOURNAL OF ONCOLOGY 2022; 2022:7802334. [PMID: 36065305 PMCID: PMC9440825 DOI: 10.1155/2022/7802334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/08/2022] [Accepted: 07/25/2022] [Indexed: 11/18/2022]
Abstract
In patients with head and neck cancer, irradiation (IR)-sensitive salivary gland (SG) tissue is highly prone to damage during radiotherapy (RT). This leads to SG hypofunction and xerostomia. Xerostomia is defined as the subjective complaint of dry mouth, which can cause other symptoms and adversely affect the quality of life. In recent years, diagnostic techniques have constantly improved with the emergence of more reliable and valid questionnaires as well as more accurate equipment for saliva flow rate measurement and imaging methods. Preventive measures such as the antioxidant MitoTEMPO, botulinum toxin (BoNT), and growth factors have been successfully applied in animal experiments, resulting in positive outcomes. Interventions, such as the new delivery methods of pilocarpine, edible saliva substitutes, acupuncture and electrical stimulation, gene transfer, and stem cell transplantation, have shown potential to alleviate or restore xerostomia in patients. The review summarizes the existing and new diagnostic methods for xerostomia, along with current and potential strategies for reducing IR-induced damage to SG function. We also aim to provide guidance on the advantages and disadvantages of the diagnostic methods. Additionally, most prevention and treatment methods remain in the stage of animal experiments, suggesting a need for further clinical research, among which we believe that antioxidants, gene transfer, and stem cell transplantation have broad prospects.
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12
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Chibly AM, Aure MH, Patel VN, Hoffman MP. Salivary Gland Function, Development and Regeneration. Physiol Rev 2022; 102:1495-1552. [PMID: 35343828 DOI: 10.1152/physrev.00015.2021] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Salivary glands produce and secrete saliva, which is essential for maintaining oral health and overall health. Understanding both the unique structure and physiological function of salivary glands, as well as how they are affected by disease and injury will direct the development of therapy to repair and regenerate them. Significant recent advances, particularly in the OMICS field, increase our understanding of how salivary glands develop at the cellular, molecular and genetic levels; the signaling pathways involved, the dynamics of progenitor cell lineages in development, homeostasis and regeneration and the role of the extracellular matrix microenvironment. These provide a template for cell and gene therapies as well as bioengineering approaches to repair or regenerate salivary function.
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Affiliation(s)
- Alejandro Martinez Chibly
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, United States
| | - Marit H Aure
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, United States
| | - Vaishali N Patel
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, United States
| | - Matthew Philip Hoffman
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, United States
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13
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Liu Z, Dong L, Zheng Z, Liu S, Gong S, Meng L, Xin Y, Jiang X. Mechanism, Prevention, and Treatment of Radiation-Induced Salivary Gland Injury Related to Oxidative Stress. Antioxidants (Basel) 2021; 10:antiox10111666. [PMID: 34829539 PMCID: PMC8614677 DOI: 10.3390/antiox10111666] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/14/2021] [Accepted: 10/19/2021] [Indexed: 12/24/2022] Open
Abstract
Radiation therapy is a common treatment for head and neck cancers. However, because of the presence of nerve structures (brain stem, spinal cord, and brachial plexus), salivary glands (SGs), mucous membranes, and swallowing muscles in the head and neck regions, radiotherapy inevitably causes damage to these normal tissues. Among them, SG injury is a serious adverse event, and its clinical manifestations include changes in taste, difficulty chewing and swallowing, oral infections, and dental caries. These clinical symptoms seriously reduce a patient’s quality of life. Therefore, it is important to clarify the mechanism of SG injury caused by radiotherapy. Although the mechanism of radiation-induced SG injury has not yet been determined, recent studies have shown that the mechanisms of calcium signaling, microvascular injury, cellular senescence, and apoptosis are closely related to oxidative stress. In this article, we review the mechanism by which radiotherapy causes oxidative stress and damages the SGs. In addition, we discuss effective methods to prevent and treat radiation-induced SG damage.
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Affiliation(s)
- Zijing Liu
- Jilin Provincial Key Laboratory of Radiation Oncology & Therapy, The First Hospital of Jilin University, Changchun 130021, China; (Z.L.); (L.D.); (Z.Z.); (S.L.); (S.G.)
- Department of Radiation Oncology, The First Hospital of Jilin University, Changchun 130021, China
- NHC Key Laboratory of Radiobiology, School of Public Health, Jilin University, Changchun 130021, China
| | - Lihua Dong
- Jilin Provincial Key Laboratory of Radiation Oncology & Therapy, The First Hospital of Jilin University, Changchun 130021, China; (Z.L.); (L.D.); (Z.Z.); (S.L.); (S.G.)
- Department of Radiation Oncology, The First Hospital of Jilin University, Changchun 130021, China
- NHC Key Laboratory of Radiobiology, School of Public Health, Jilin University, Changchun 130021, China
| | - Zhuangzhuang Zheng
- Jilin Provincial Key Laboratory of Radiation Oncology & Therapy, The First Hospital of Jilin University, Changchun 130021, China; (Z.L.); (L.D.); (Z.Z.); (S.L.); (S.G.)
- Department of Radiation Oncology, The First Hospital of Jilin University, Changchun 130021, China
- NHC Key Laboratory of Radiobiology, School of Public Health, Jilin University, Changchun 130021, China
| | - Shiyu Liu
- Jilin Provincial Key Laboratory of Radiation Oncology & Therapy, The First Hospital of Jilin University, Changchun 130021, China; (Z.L.); (L.D.); (Z.Z.); (S.L.); (S.G.)
- Department of Radiation Oncology, The First Hospital of Jilin University, Changchun 130021, China
- NHC Key Laboratory of Radiobiology, School of Public Health, Jilin University, Changchun 130021, China
| | - Shouliang Gong
- Jilin Provincial Key Laboratory of Radiation Oncology & Therapy, The First Hospital of Jilin University, Changchun 130021, China; (Z.L.); (L.D.); (Z.Z.); (S.L.); (S.G.)
- Department of Radiation Oncology, The First Hospital of Jilin University, Changchun 130021, China
- NHC Key Laboratory of Radiobiology, School of Public Health, Jilin University, Changchun 130021, China
| | - Lingbin Meng
- Department of Hematology and Medical Oncology, Moffitt Cancer Center, Tampa, FL 33612, USA;
| | - Ying Xin
- Key Laboratory of Pathobiology, Ministry of Education, Jilin University, Changchun 130021, China;
| | - Xin Jiang
- Jilin Provincial Key Laboratory of Radiation Oncology & Therapy, The First Hospital of Jilin University, Changchun 130021, China; (Z.L.); (L.D.); (Z.Z.); (S.L.); (S.G.)
- Department of Radiation Oncology, The First Hospital of Jilin University, Changchun 130021, China
- NHC Key Laboratory of Radiobiology, School of Public Health, Jilin University, Changchun 130021, China
- Correspondence: ; Tel.: +86-158-0430-2750
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Meeks L, De Oliveira Pessoa D, Martinez JA, Limesand KH, Padi M. Integration of metabolomics and transcriptomics reveals convergent pathways driving radiation-induced salivary gland dysfunction. Physiol Genomics 2021; 53:85-98. [PMID: 33522389 PMCID: PMC7988743 DOI: 10.1152/physiolgenomics.00127.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 01/04/2021] [Accepted: 01/22/2021] [Indexed: 11/22/2022] Open
Abstract
Radiation therapy for head and neck cancer causes damage to the surrounding salivary glands, resulting in salivary gland hypofunction and xerostomia. Current treatments do not provide lasting restoration of salivary gland function following radiation; therefore, a new mechanistic understanding of the radiation-induced damage response is necessary for identifying therapeutic targets. The purpose of the present study was to investigate the metabolic phenotype of radiation-induced damage in parotid salivary glands by integrating transcriptomic and metabolomic data. Integrated data were then analyzed to identify significant gene-metabolite interactions. Mice received a single 5 Gy dose of targeted head and neck radiation. Parotid tissue samples were collected 5 days following treatment for RNA sequencing and metabolomics analysis. Altered metabolites and transcripts significantly converged on a specific region in the metabolic reaction network. Both integrative pathway enrichment using rank-based statistics and network analysis highlighted significantly coordinated changes in glutathione metabolism, energy metabolism (TCA cycle and thermogenesis), peroxisomal lipid metabolism, and bile acid production with radiation. Integrated changes observed in energy metabolism suggest that radiation induces a mitochondrial dysfunction phenotype. These findings validated previous pathways involved in the radiation-damage response, such as altered energy metabolism, and identified robust signatures in salivary glands, such as reduced glutathione metabolism, that may be driving salivary gland dysfunction.
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Affiliation(s)
- Lauren Meeks
- Department of Nutritional Sciences, University of Arizona, Tucson, Arizona
| | | | - Jessica A Martinez
- Department of Nutritional Sciences, University of Arizona, Tucson, Arizona
- University of Arizona Cancer Center, Tucson, Arizona
| | - Kirsten H Limesand
- Department of Nutritional Sciences, University of Arizona, Tucson, Arizona
- University of Arizona Cancer Center, Tucson, Arizona
| | - Megha Padi
- Bioinformatics Shared Resource, Arizona Cancer Center, University of Arizona, Tucson, Arizona
- University of Arizona Cancer Center, Tucson, Arizona
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona
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15
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Serrano Martinez P, Giuranno L, Vooijs M, Coppes RP. The Radiation-Induced Regenerative Response of Adult Tissue-Specific Stem Cells: Models and Signaling Pathways. Cancers (Basel) 2021; 13:cancers13040855. [PMID: 33670536 PMCID: PMC7921940 DOI: 10.3390/cancers13040855] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 02/10/2021] [Accepted: 02/14/2021] [Indexed: 02/07/2023] Open
Abstract
Radiotherapy is involved in the treatment of many cancers, but damage induced to the surrounding normal tissue is often inevitable. Evidence suggests that the maintenance of homeostasis and regeneration of the normal tissue is driven by specific adult tissue stem/progenitor cells. These tasks involve the input from several signaling pathways. Irradiation also targets these stem/progenitor cells, triggering a cellular response aimed at achieving tissue regeneration. Here we discuss the currently used in vitro and in vivo models and the involved specific tissue stem/progenitor cell signaling pathways to study the response to irradiation. The combination of the use of complex in vitro models that offer high in vivo resemblance and lineage tracing models, which address organ complexity constitute potential tools for the study of the stem/progenitor cellular response post-irradiation. The Notch, Wnt, Hippo, Hedgehog, and autophagy signaling pathways have been found as crucial for driving stem/progenitor radiation-induced tissue regeneration. We review how these signaling pathways drive the response of solid tissue-specific stem/progenitor cells to radiotherapy and the used models to address this.
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Affiliation(s)
- Paola Serrano Martinez
- Department of Biomedical Sciences of Cells and Systems-Section Molecular Cell Biology, University of Groningen, University Medical Center Groningen, 9713 AV Groningen, The Netherlands;
- Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, The Netherlands
| | - Lorena Giuranno
- Department of Radiation Oncology (Maastro), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, P.O. Box 616, 6200 MD Maastricht, The Netherlands;
| | - Marc Vooijs
- Department of Radiation Oncology (Maastro), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, P.O. Box 616, 6200 MD Maastricht, The Netherlands;
- Correspondence: (M.V.); (R.P.C.)
| | - Robert P. Coppes
- Department of Biomedical Sciences of Cells and Systems-Section Molecular Cell Biology, University of Groningen, University Medical Center Groningen, 9713 AV Groningen, The Netherlands;
- Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, The Netherlands
- Correspondence: (M.V.); (R.P.C.)
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16
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Radiation-Induced Salivary Gland Dysfunction: Mechanisms, Therapeutics and Future Directions. J Clin Med 2020; 9:jcm9124095. [PMID: 33353023 PMCID: PMC7767137 DOI: 10.3390/jcm9124095] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/17/2020] [Accepted: 12/17/2020] [Indexed: 12/14/2022] Open
Abstract
Salivary glands sustain collateral damage following radiotherapy (RT) to treat cancers of the head and neck, leading to complications, including mucositis, xerostomia and hyposalivation. Despite salivary gland-sparing techniques and modified dosing strategies, long-term hypofunction remains a significant problem. Current therapeutic interventions provide temporary symptom relief, but do not address irreversible glandular damage. In this review, we summarize the current understanding of mechanisms involved in RT-induced hyposalivation and provide a framework for future mechanistic studies. One glaring gap in published studies investigating RT-induced mechanisms of salivary gland dysfunction concerns the effect of irradiation on adjacent non-irradiated tissue via paracrine, autocrine and direct cell-cell interactions, coined the bystander effect in other models of RT-induced damage. We hypothesize that purinergic receptor signaling involving P2 nucleotide receptors may play a key role in mediating the bystander effect. We also discuss promising new therapeutic approaches to prevent salivary gland damage due to RT.
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17
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Wong WY, Gilman K, Limesand KH. Yap activation in irradiated parotid salivary glands is regulated by ROCK activity. PLoS One 2020; 15:e0232921. [PMID: 33151927 PMCID: PMC7644026 DOI: 10.1371/journal.pone.0232921] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 10/19/2020] [Indexed: 02/07/2023] Open
Abstract
Radiotherapy plays a major role in the curative treatment of head and neck cancer, either as a single modality therapy, or in combination with surgery or chemotherapy, or both. Despite advances to limit radiation-induced side-effects, the major salivary glands are often affected. This frequently leads to hyposalivation which causes an increased risk for xerostomia, dental caries, mucositis, and malnutrition culminating in a significant impact on patients' quality of life. Previous research demonstrated that loss of salivary function is associated with a decrease in polarity regulators and an increase in nuclear Yap localization in a putative stem and progenitor cell (SPC) population. Yap activation has been shown to be essential for regeneration in intestinal injury models; however, the highest levels of nuclear Yap are observed in irradiated salivary SPCs that do not regenerate the gland. Thus, elucidating the inputs that regulate nuclear Yap localization and determining the role that Yap plays within the entire tissue following radiation damage and during regeneration is critical. In this study, we demonstrate that radiation treatment increases nuclear Yap localization in acinar cells and Yap-regulated genes in parotid salivary tissues. Conversely, administration of insulin-like growth factor 1 (IGF1), known to restore salivary function in mouse models, reduces nuclear Yap localization and Yap transcriptional targets to levels similar to untreated tissues. Activation of Rho-associated protein kinase (ROCK) using calpeptin results in increased Yap-regulated genes in primary acinar cells while inhibition of ROCK activity (Y-27632) leads to decreased Yap transcriptional targets. These results suggest that Yap activity is dependent on ROCK activity and provides new mechanistic insights into the regulation of radiation-induced hyposalivation.
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Affiliation(s)
- Wen Yu Wong
- Cancer Biology Graduate Interdisciplinary Program, University of Arizona, Tucson, AZ, United States of America
| | - Kristy Gilman
- Department of Nutritional Sciences, University of Arizona, Tucson, AZ, United States of America
| | - Kirsten H. Limesand
- Cancer Biology Graduate Interdisciplinary Program, University of Arizona, Tucson, AZ, United States of America
- Department of Nutritional Sciences, University of Arizona, Tucson, AZ, United States of America
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18
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Baptista-de-Souza D, Tavares-Ferreira D, Megat S, Sankaranarayanan I, Shiers S, Flores CM, Ghosh S, Luiz Nunes-de-Souza R, Canto-de-Souza A, Price TJ. Sex differences in the role of atypical PKC within the basolateral nucleus of the amygdala in a mouse hyperalgesic priming model. NEUROBIOLOGY OF PAIN (CAMBRIDGE, MASS.) 2020; 8:100049. [PMID: 32548337 PMCID: PMC7284072 DOI: 10.1016/j.ynpai.2020.100049] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 05/07/2020] [Accepted: 06/01/2020] [Indexed: 04/15/2023]
Abstract
Though sex differences in chronic pain have been consistently described in the literature, their underlying neural mechanisms are poorly understood. Previous work in humans has demonstrated that men and women differentially invoke distinct brain regions and circuits in coping with subjective pain unpleasantness. The goal of the present work was to elucidate the molecular mechanisms in the basolateral nucleus of the amygdala (BLA) that modulate hyperalgesic priming, a pain plasticity model, in males and females. We used plantar incision as the first, priming stimulus and prostaglandin E2 (PGE2) as the second stimulus. We sought to assess whether hyperalgesic priming can be prevented or reversed by pharmacologically manipulating molecular targets in the BLA of male or female mice. We found that administering ZIP, a cell-permeable inhibitor of aPKC, into the BLA attenuated aspects of hyperalgesic priming induced by plantar incision in males and females. However, incision only upregulated PKCζ/PKMζ immunoreactivity in the BLA of male mice, and deficits in hyperalgesic priming were seen only when we restricted our analysis to male Prkcz-/- mice. On the other hand, intra-BLA microinjections of pep2m, a peptide that interferes with the trafficking and function of GluA2-containing AMPA receptors, a downstream target of aPKC, reduced mechanical hypersensitivity after plantar incision and disrupted the development of hyperalgesic priming in both male and female mice. In addition, pep2m treatment reduced facial grimacing and restored aberrant behavioral responses in the sucrose splash test in male and female primed mice. Immunofluorescence results demonstrated upregulation of GluA2 expression in the BLA of male and female primed mice, consistent with pep2m findings. We conclude that, in a model of incision-induced hyperalgesic priming, PKCζ/PKMζ in the BLA is critical for the development of hyperalgesic priming in males, while GluA2 in the BLA is crucial for the expression of both reflexive and affective pain-related behaviors in both male and female mice in this model. Our findings add to a growing body of evidence of sex differences in molecular pain mechanisms in the brain.
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Affiliation(s)
- Daniela Baptista-de-Souza
- Dept. Psychology, Federal University of Sao Carlos-UFSCar, Sao Carlos, SP 13565-905, Brazil
- University of Texas at Dallas, School of Behavioral and Brain Sciences and Center for Advanced Pain Studies, United States
| | - Diana Tavares-Ferreira
- University of Texas at Dallas, School of Behavioral and Brain Sciences and Center for Advanced Pain Studies, United States
| | - Salim Megat
- University of Texas at Dallas, School of Behavioral and Brain Sciences and Center for Advanced Pain Studies, United States
| | - Ishwarya Sankaranarayanan
- University of Texas at Dallas, School of Behavioral and Brain Sciences and Center for Advanced Pain Studies, United States
| | - Stephanie Shiers
- University of Texas at Dallas, School of Behavioral and Brain Sciences and Center for Advanced Pain Studies, United States
| | - Christopher M. Flores
- Janssen Research & Development, Neuroscience Therapeutic Area, San Diego, CA, United States
| | - Sourav Ghosh
- Yale University School of Medicine, Department of Neurology, United States
| | - Ricardo Luiz Nunes-de-Souza
- Joint Graduate Program in Physiological Sciences UFSCar/UNESP, São Carlos, SP 13565-905, Brazil
- Lab. Pharmacology, School of Pharmaceutical Sciences, Univ. Estadual Paulista – UNESP, Araraquara, SP 14800-903, Brazil
| | - Azair Canto-de-Souza
- Dept. Psychology, Federal University of Sao Carlos-UFSCar, Sao Carlos, SP 13565-905, Brazil
- Joint Graduate Program in Physiological Sciences UFSCar/UNESP, São Carlos, SP 13565-905, Brazil
- Graduate Program in Psychology UFSCar, São Carlos, SP 13565-905, Brazil
| | - Theodore J. Price
- University of Texas at Dallas, School of Behavioral and Brain Sciences and Center for Advanced Pain Studies, United States
- Corresponding author at: University of Texas at Dallas, School of Behavioral and Brain Sciences, 800 W Campbell Rd., BSB 14.102, Richardson, TX 75080, United States.
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19
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Jensen SB, Vissink A, Limesand KH, Reyland ME. Salivary Gland Hypofunction and Xerostomia in Head and Neck Radiation Patients. J Natl Cancer Inst Monogr 2020; 2019:5551361. [PMID: 31425600 DOI: 10.1093/jncimonographs/lgz016] [Citation(s) in RCA: 95] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 05/21/2019] [Accepted: 05/26/2019] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND The most manifest long-term consequences of radiation therapy in the head and neck cancer patient are salivary gland hypofunction and a sensation of oral dryness (xerostomia). METHODS This critical review addresses the consequences of radiation injury to salivary gland tissue, the clinical management of salivary gland hypofunction and xerostomia, and current and potential strategies to prevent or reduce radiation injury to salivary gland tissue or restore the function of radiation-injured salivary gland tissue. RESULTS Salivary gland hypofunction and xerostomia have severe implications for oral functioning, maintenance of oral and general health, and quality of life. Significant progress has been made to spare salivary gland function chiefly due to advances in radiation techniques. Other strategies have also been developed, e.g., radioprotectors, identification and preservation/expansion of salivary stem cells by stimulation with cholinergic muscarinic agonists, and application of new lubricating or stimulatory agents, surgical transfer of submandibular glands, and acupuncture. CONCLUSION Many advances to manage salivary gland hypofunction and xerostomia induced by radiation therapy still only offer partial protection since they are often of short duration, lack the protective effects of saliva, or potentially have significant adverse effects. Intensity-modulated radiation therapy (IMRT), and its next step, proton therapy, have the greatest potential as a management strategy for permanently preserving salivary gland function in head and neck cancer patients.Presently, gene transfer to supplement fluid formation and stem cell transfer to increase the regenerative potential in radiation-damaged salivary glands are promising approaches for regaining function and/or regeneration of radiation-damaged salivary gland tissue.
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Affiliation(s)
- Siri Beier Jensen
- Department of Dentistry and Oral Health, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Arjan Vissink
- Department of Oral and Maxillofacial Surgery, University of Groningen, University Medical Center, Groningen, The Netherlands
| | | | - Mary E Reyland
- Department of Craniofacial Biology, School of Dental Medicine, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO
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Serrano Martinez P, Cinat D, van Luijk P, Baanstra M, de Haan G, Pringle S, Coppes RP. Mouse parotid salivary gland organoids for the in vitro study of stem cell radiation response. Oral Dis 2020; 27:52-63. [PMID: 32531849 PMCID: PMC7818507 DOI: 10.1111/odi.13475] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 05/18/2020] [Accepted: 06/01/2020] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Hyposalivation-related xerostomia is an irreversible, untreatable, and frequent condition after radiotherapy for head and neck cancer. Stem cell therapy is an attractive option of treatment, but demands knowledge of stem cell functioning. Therefore, we aimed to develop a murine parotid gland organoid model to explore radiation response of stem cells in vitro. MATERIALS AND METHODS Single cells derived from murine parotid gland organoids were passaged in Matrigel with defined medium to assess self-renewal and differentiation potential. Single cells were irradiated and plated in a 3D clonogenic stem cell survival assay to assess submandibular and parotid gland radiation response. RESULTS Single cells derived from parotid gland organoids were able to extensively self-renew and differentiate into all major tissue cell types, indicating the presence of potential stem cells. FACS selection for known salivary gland stem cell markers CD24/CD29 did not further enrich for stem cells. The parotid gland organoid-derived stem cells displayed radiation dose-response curves similar to the submandibular gland. CONCLUSIONS Murine parotid gland organoids harbor stem cells with long-term expansion and differentiation potential. This model is useful for mechanistic studies of stem cell radiation response and suggests similar radiosensitivity for the parotid and submandibular gland organoids.
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Affiliation(s)
- Paola Serrano Martinez
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.,Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Davide Cinat
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.,Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Peter van Luijk
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Mirjam Baanstra
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.,Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Gerald de Haan
- European Research Institute for the Biology of Ageing, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Sarah Pringle
- Department of Rheumatology and Clinical Immunology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Robert P Coppes
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.,Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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21
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Khalafalla MG, Woods LT, Jasmer KJ, Forti KM, Camden JM, Jensen JL, Limesand KH, Galtung HK, Weisman GA. P2 Receptors as Therapeutic Targets in the Salivary Gland: From Physiology to Dysfunction. Front Pharmacol 2020; 11:222. [PMID: 32231563 PMCID: PMC7082426 DOI: 10.3389/fphar.2020.00222] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 02/18/2020] [Indexed: 12/12/2022] Open
Abstract
Although often overlooked in our daily lives, saliva performs a host of necessary physiological functions, including lubricating and protecting the oral cavity, facilitating taste sensation and digestion and maintaining tooth enamel. Therefore, salivary gland dysfunction and hyposalivation, often resulting from pathogenesis of the autoimmune disease Sjögren's syndrome or from radiotherapy of the head and neck region during cancer treatment, severely reduce the quality of life of afflicted patients and can lead to dental caries, periodontitis, digestive disorders, loss of taste and difficulty speaking. Since their initial discovery in the 1970s, P2 purinergic receptors for extracellular nucleotides, including ATP-gated ion channel P2X and G protein-coupled P2Y receptors, have been shown to mediate physiological processes in numerous tissues, including the salivary glands where P2 receptors represent a link between canonical and non-canonical saliva secretion. Additionally, extracellular nucleotides released during periods of cellular stress and inflammation act as a tissue alarmin to coordinate immunological and tissue repair responses through P2 receptor activation. Accordingly, P2 receptors have gained widespread clinical interest with agonists and antagonists either currently undergoing clinical trials or already approved for human use. Here, we review the contributions of P2 receptors to salivary gland function and describe their role in salivary gland dysfunction. We further consider their potential as therapeutic targets to promote physiological saliva flow, prevent salivary gland inflammation and enhance tissue regeneration.
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Affiliation(s)
- Mahmoud G. Khalafalla
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Lucas T. Woods
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Kimberly J. Jasmer
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Kevin Muñoz Forti
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Jean M. Camden
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Janicke L. Jensen
- Institute of Clinical Dentistry, Section of Oral Surgery and Oral Medicine, University of Oslo, Oslo, Norway
| | - Kirsten H. Limesand
- Department of Nutritional Sciences, University of Arizona, Tucson, AZ, United States
| | - Hilde K. Galtung
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Gary A. Weisman
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
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22
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Aure MH, Symonds JM, Mays JW, Hoffman MP. Epithelial Cell Lineage and Signaling in Murine Salivary Glands. J Dent Res 2019; 98:1186-1194. [PMID: 31331226 DOI: 10.1177/0022034519864592] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Maintaining salivary gland function is critical for oral health. Loss of saliva is a common side effect of therapeutic irradiation for head and neck cancer or autoimmune diseases such as Sjögren's syndrome. There is no curative treatment, and current strategies proposed for functional regeneration include gene therapy to reengineer surviving salivary gland tissue, cell-based transplant therapy, use of bioengineered glands, and development of drugs/biologics to stimulate in vivo regeneration or increase secretion. Understanding the genetic and cellular mechanisms required for development and homeostasis of adult glands is essential to the success of these proposed treatments. Recent advances in genetic lineage tracing provide insight into epithelial lineage relationships during murine salivary gland development. During early fetal gland development, epithelial cells expressing keratin 14 (K14) Sox2, Sox9, Sox10, and Trp63 give rise to all adult epithelium, but as development proceeds, lineage restriction occurs, resulting in separate lineages of myoepithelial, ductal, and acinar cells in postnatal glands. Several niche signals have been identified that regulate epithelial development and lineage restriction. Fibroblast growth factor signaling is essential for gland development, and other important factors that influence epithelial patterning and maturation include the Wnt, Hedgehog, retinoic acid, and Hippo signaling pathways. In addition, other cell types in the local microenvironment, such as endothelial and neuronal cells, can influence epithelial development. Emerging evidence also suggests that specific epithelial cells will respond to different types of salivary gland damage, depending on the cause and severity of damage and the resulting damaged microenvironment. Understanding how regeneration occurs and which cell types are affected, as well as which signaling factors drive cell lineage decisions, provides specific targets to manipulate cell fate and improve regeneration. Taken together, these recent advances in understanding cell lineages and the signaling factors that drive cell fate changes provide a guide to develop novel regenerative treatments.
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Affiliation(s)
- M H Aure
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA.,Oral Immunobiology Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
| | - J M Symonds
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA.,Current address: Chromodex Spherix Consulting, Rockville, MD, USA
| | - J W Mays
- Oral Immunobiology Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
| | - M P Hoffman
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
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23
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Wong WY, Allie S, Limesand KH. PKCζ and JNK signaling regulate radiation-induced compensatory proliferation in parotid salivary glands. PLoS One 2019; 14:e0219572. [PMID: 31287841 PMCID: PMC6615637 DOI: 10.1371/journal.pone.0219572] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 06/26/2019] [Indexed: 01/05/2023] Open
Abstract
Radiotherapy is a common treatment option for head and neck cancer patients; however, the surrounding healthy salivary glands are often incidentally irradiated during the process. As a result, patients often experience persistent xerostomia and hyposalivation, which deceases their quality of life. Clinically, there is currently no standard of care available to restore salivary function. Repair of epithelial wounds involves cellular proliferation and establishment of polarity in order to regenerate the tissue. This process is partially mediated by protein kinase C zeta (PKCζ), an apical polarity regulator; however, its role following radiation damage is not completely understood. Using an in vivo radiation model, we show a significant decrease in active PKCζ in irradiated murine parotid glands, which correlates with increased proliferation that is sustained through 30 days post-irradiation. Additionally, salivary glands in PKCζ null mice show increased basal proliferation which radiation treatment did not further potentiate. Radiation damage also activates Jun N-terminal kinase (JNK), a proliferation-inducing mitogen-activated protein kinase normally inhibited by PKCζ. In both a PKCζ null mouse model and in primary salivary gland cell cultures treated with a PKCζ inhibitor, there was increased JNK activity and production of downstream proliferative transcripts. Collectively, these findings provide a potential molecular link by which PKCζ suppression following radiation damage promotes JNK activation and radiation-induced compensatory proliferation in the salivary gland.
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Affiliation(s)
- Wen Yu Wong
- Cancer Biology Graduate Interdisciplinary Program, University of Arizona, Tucson, Arizona, United States of America
| | - Sydney Allie
- Department of Nutritional Sciences, University of Arizona, Tucson, Arizona, United States of America
| | - Kirsten H. Limesand
- Cancer Biology Graduate Interdisciplinary Program, University of Arizona, Tucson, Arizona, United States of America
- Department of Nutritional Sciences, University of Arizona, Tucson, Arizona, United States of America
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24
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Weng PL, Aure MH, Ovitt CE. Concise Review: A Critical Evaluation of Criteria Used to Define Salivary Gland Stem Cells. Stem Cells 2019; 37:1144-1150. [PMID: 31175700 DOI: 10.1002/stem.3046] [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: 02/01/2019] [Accepted: 05/20/2019] [Indexed: 12/19/2022]
Abstract
In the effort to develop cell-based therapies to treat salivary gland dysfunction, many different populations of cells in the adult salivary glands have been proposed as stem cells. These cell populations vary, depending on the assay used, and are often nonoverlapping, leading to the conclusion that salivary glands harbor multiple stem cells. The goal of this review is to critically appraise the assays and properties used to identify stem cells in the adult salivary gland, and to consider the caveats of each. Re-evaluation of the defining criteria may help to reconcile the many potential stem cell populations described in the salivary gland, in order to increase comparability between studies and build consensus in the field. Stem Cells 2019;37:1144-1150.
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Affiliation(s)
- Pei-Lun Weng
- Department of Dermatology, Yale University, New Haven, Connecticut, USA.,Department of Pathology, Yale University, New Haven, Connecticut, USA
| | - Marit H Aure
- Matrix and Morphology Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, USA
| | - Catherine E Ovitt
- Center for Oral Biology, Department of Biomedical Genetics, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
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25
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Meyer R, Wong WY, Guzman R, Burd R, Limesand K. Radiation Treatment of Organotypic Cultures from Submandibular and Parotid Salivary Glands Models Key In Vivo Characteristics. J Vis Exp 2019. [PMID: 31157788 DOI: 10.3791/59484] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Hyposalivation and xerostomia create chronic oral complications that decrease the quality of life in head and neck cancer patients who are treated with radiotherapy. Experimental approaches to understanding mechanisms of salivary gland dysfunction and restoration have focused on in vivo models, which are handicapped by an inability to systematically screen therapeutic candidates and efficiencies in transfection capability to manipulate specific genes. The purpose of this salivary gland organotypic culture protocol is to evaluate maximal time of culture viability and characterize cellular changes following ex vivo radiation treatment. We utilized immunofluorescent staining and confocal microscopy to determine when specific cell populations and markers are present during a 30-day culture period. In addition, cellular markers previously reported in in vivo radiation models are evaluated in cultures that are irradiated ex vivo. Moving forward, this method is an attractive platform for rapid ex vivo assessment of murine and human salivary gland tissue responses to therapeutic agents that improve salivary function.
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Affiliation(s)
- Rachel Meyer
- Department of Nutritional Sciences, University of Arizona
| | - Wen Yu Wong
- Cancer Biology Graduate Interdisciplinary Program, University of Arizona
| | - Roberto Guzman
- Department of Chemical Engineering, University of Arizona
| | - Randy Burd
- Department of Nutritional Sciences, University of Arizona
| | - Kirsten Limesand
- Department of Nutritional Sciences, University of Arizona; Cancer Biology Graduate Interdisciplinary Program, University of Arizona;
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26
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Wong WY, Pier M, Limesand KH. Persistent disruption of lateral junctional complexes and actin cytoskeleton in parotid salivary glands following radiation treatment. Am J Physiol Regul Integr Comp Physiol 2018; 315:R656-R667. [PMID: 29897817 PMCID: PMC6230885 DOI: 10.1152/ajpregu.00388.2017] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 06/11/2018] [Accepted: 06/12/2018] [Indexed: 02/02/2023]
Abstract
Xerostomia and hyposalivation are debilitating side effects for patients treated with ionizing radiation for head and neck cancer. Despite technological advances, collateral damage to the salivary glands remains a significant problem for patients and severely diminishes their quality of life. During the wound healing process, restoration of junctional contacts is necessary to maintain polarity, structural integrity, and orientation cues for secretion. However, little is known about whether these structural molecules are impacted following radiation damage and more importantly, during tissue restoration. We evaluated changes in adherens junctions and cytoskeletal regulators in an injury model where mice were irradiated with 5 Gy and a restoration model where mice injected postradiation with insulin-like growth factor 1 (IGF1) are capable of restoring salivary function. Using coimmunoprecipitation, there is a decrease in epithelial (E)-cadherin bound to β-catenin following damage that is restored to untreated levels with IGF1. Via its adaptor proteins, β-catenin links the cadherins to the cytoskeleton and part of this regulation is mediated through Rho-associated coiled-coil containing kinase (ROCK) signaling. In our radiation model, filamentous (F)-actin organization is fragmented, and there is an induction of ROCK activity. However, a ROCK inhibitor, Y-27632, prevents E-cadherin/β-catenin dissociation following radiation treatment. These findings illustrate that radiation induces a ROCK-dependent disruption of the cadherin-catenin complex and alters F-actin organization at stages of damage when hyposalivation is observed. Understanding the regulation of these components will be critical in the discovery of therapeutics that have the potential to restore function in polarized epithelium.
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Affiliation(s)
- Wen Yu Wong
- Cancer Biology Graduate Interdisciplinary Program, University of Arizona , Tucson, Arizona
| | - Maricela Pier
- Department of Nutritional Sciences, University of Arizona , Tucson, Arizona
| | - Kirsten H Limesand
- Cancer Biology Graduate Interdisciplinary Program, University of Arizona , Tucson, Arizona
- Department of Nutritional Sciences, University of Arizona , Tucson, Arizona
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