1
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Fernandez Garcia E, Paudel U, Noji MC, Bowman CE, Rustgi AK, Pitarresi JR, Wellen KE, Arany Z, Weissenrieder JS, Foskett JK. The mitochondrial Ca 2+ channel MCU is critical for tumor growth by supporting cell cycle progression and proliferation. Front Cell Dev Biol 2023; 11:1082213. [PMID: 37363724 PMCID: PMC10285664 DOI: 10.3389/fcell.2023.1082213] [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: 10/27/2022] [Accepted: 05/09/2023] [Indexed: 06/28/2023] Open
Abstract
Introduction: The mitochondrial uniporter (MCU) Ca2+ ion channel represents the primary means for Ca2+ uptake by mitochondria. Mitochondrial matrix Ca2+ plays critical roles in mitochondrial bioenergetics by impinging upon respiration, energy production and flux of biochemical intermediates through the TCA cycle. Inhibition of MCU in oncogenic cell lines results in an energetic crisis and reduced cell proliferation unless media is supplemented with nucleosides, pyruvate or α-KG. Nevertheless, the roles of MCU-mediated Ca2+ influx in cancer cells remain unclear, in part because of a lack of genetic models. Methods: MCU was genetically deleted in transformed murine fibroblasts for study in vitro and in vivo. Tumor formation and growth were studied in murine xenograft models. Proliferation, cell invasion, spheroid formation and cell cycle progression were measured in vitro. The effects of MCU deletion on survival and cell-death were determined by probing for live/death markers. Mitochondrial bioenergetics were studied by measuring mitochondrial matrix Ca2+ concentration, membrane potential, global dehydrogenase activity, respiration, ROS production and inactivating-phosphorylation of pyruvate dehydrogenase. The effects of MCU rescue on metabolism were examined by tracing of glucose and glutamine utilization for fueling of mitochondrial respiration. Results: Transformation of primary fibroblasts in vitro was associated with increased MCU expression, enhanced MCU-mediated Ca2+ uptake, altered mitochondrial matrix Ca2+ concentration responses to agonist stimulation, suppression of inactivating-phosphorylation of pyruvate dehydrogenase and a modest increase of mitochondrial respiration. Genetic MCU deletion inhibited growth of HEK293T cells and transformed fibroblasts in mouse xenograft models, associated with reduced proliferation and delayed cell-cycle progression. MCU deletion inhibited cancer stem cell-like spheroid formation and cell invasion in vitro, both predictors of metastatic potential. Surprisingly, mitochondrial matrix [Ca2+], membrane potential, global dehydrogenase activity, respiration and ROS production were unaffected. In contrast, MCU deletion elevated glycolysis and glutaminolysis, strongly sensitized cell proliferation to glucose and glutamine limitation, and altered agonist-induced cytoplasmic Ca2+ signals. Conclusion: Our results reveal a dependence of tumorigenesis on MCU, mediated by a reliance on MCU for cell metabolism and Ca2+ dynamics necessary for cell-cycle progression and cell proliferation.
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Affiliation(s)
- Emily Fernandez Garcia
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Usha Paudel
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Michael C. Noji
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Medicine, Perelman School of Medicine, Cardiovascular Institute, University of Pennsylvania, Philadelphia, PA, United States
| | - Caitlyn E. Bowman
- Department of Medicine, Perelman School of Medicine, Cardiovascular Institute, University of Pennsylvania, Philadelphia, PA, United States
| | - Anil K. Rustgi
- Division of Digestive and Liver Diseases, Herbert Irving Comprehensive Cancer Center, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, New York, NY, United States
| | - Jason R. Pitarresi
- Division of Hematology/Oncology, Departments of Medicine and Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Kathryn E. Wellen
- Department of Cancer Biology and Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Zolt Arany
- Department of Medicine, Perelman School of Medicine, Cardiovascular Institute, University of Pennsylvania, Philadelphia, PA, United States
| | - Jillian S. Weissenrieder
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - J. Kevin Foskett
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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2
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García EF, Paudel U, Noji MC, Bowman CE, Pitarresi JR, Rustgi AK, Wellen KE, Arany Z, Weissenrieder JS, Foskett JK. The mitochondrial Ca 2+ channel MCU is critical for tumor growth by supporting cell cycle progression and proliferation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.26.538295. [PMID: 37163088 PMCID: PMC10168388 DOI: 10.1101/2023.04.26.538295] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The mitochondrial uniporter (MCU) Ca 2+ ion channel represents the primary means for Ca 2+ uptake into mitochondria. Here we employed in vitro and in vivo models with MCU genetically eliminated to understand how MCU contributes to tumor formation and progression. Transformation of primary fibroblasts in vitro was associated with increased MCU expression, enhanced mitochondrial Ca 2+ uptake, suppression of inactivating-phosphorylation of pyruvate dehydrogenase, a modest increase of basal mitochondrial respiration and a significant increase of acute Ca 2+ -dependent stimulation of mitochondrial respiration. Inhibition of mitochondrial Ca 2+ uptake by genetic deletion of MCU markedly inhibited growth of HEK293T cells and of transformed fibroblasts in mouse xenograft models. Reduced tumor growth was primarily a result of substantially reduced proliferation and fewer mitotic cells in vivo , and slower cell proliferation in vitro associated with delayed progression through S-phase of the cell cycle. MCU deletion inhibited cancer stem cell-like spheroid formation and cell invasion in vitro , both predictors of metastatic potential. Surprisingly, mitochondrial matrix Ca 2+ concentration, membrane potential, global dehydrogenase activity, respiration and ROS production were unchanged by genetic deletion of MCU in transformed cells. In contrast, MCU deletion elevated glycolysis and glutaminolysis, strongly sensitized cell proliferation to glucose and glutamine limitation, and altered agonist-induced cytoplasmic Ca 2+ signals. Our results reveal a dependence of tumorigenesis on MCU, mediated by a reliance on mitochondrial Ca 2+ uptake for cell metabolism and Ca 2+ dynamics necessary for cell-cycle progression and cell proliferation.
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3
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Sheweita SA, El-Masry YM, Zaghloul TI, Mostafa SK, Elgindy NA. Preclinical studies on melanogenesis proteins using a resveratrol-nanoformula as a skin whitener. Int J Biol Macromol 2022; 223:870-881. [PMID: 36370858 DOI: 10.1016/j.ijbiomac.2022.11.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 11/03/2022] [Accepted: 11/04/2022] [Indexed: 11/10/2022]
Abstract
A naturally occurring polyphenol called trans-resveratrol has received a lot of attention due to its possible health advantages for humans. The low solubility of trans-resveratrol and its isomerization upon UV exposure strongly limit its application as a skin-whitening agent. In the present study, to increase trans-resveratrol solubility, a new nanoformula was created by combining hydrophilic surfactants and oils. Trans-Resveratrol nanoformula has been prepared, characterized, and applied as a skin-whitening agent on the dorsal skin of Guinea pigs. The optimized trans-resveratrol nanoformula with a particle size of 63.49 nm displayed a single peak and a polydispersity index [0.36 ± 0.02]. In addition, the zeta potential of the optimized formula was -30.4 mV, confirming the high stability of this nanoformula. The melanin contents in the trans-resveratrol nanoformula-treated group were substantially lower than those of the control and the blank nanoformula-treated groups after staining of the dorsal skins [black areas] of guinea pigs with Fontana Mountain dye. The pigmentation index in the control, blank nanoformula, and optimized trans-resveratrol nanoformula were 329.4 ± 36.9, 335.8 ± 71.4, and 124.8 ± 19.6 respectively. Confirming this finding, immunohistochemistry analysis of skin tissues revealed that the expressions of melanogenesis-regulating proteins such as tyrosinase and microphthalmia-associated transcription factor were down-regulated. The safety of topical application of trans-resveratrol nanoformula was validated by no changes in free radical levels and oxidative stress markers proteins in the livers and kidneys of guinea pigs at the end of the experiment. Conclusions: A novel trans-resveratrol nanoformula as well as the mechanism whereby it promotes skin whitening effects were presented. Furthermore, the study illustrated that trans-resveratrol nanoformula is safe, non-toxic, and can be applied for skin whitening, although more research on human skin is needed.
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Affiliation(s)
- Salah A Sheweita
- Department of Clinical Biochemistry, Faculty of Medicine, King Khalid University, Abha, KSA; Department of Biotechnology, Institute of Graduate Studies and Research, Alexandria University, Alexandria 21526, Egypt.
| | - Yassin M El-Masry
- Department of Biotechnology, Institute of Graduate Studies and Research, Alexandria University, Alexandria 21526, Egypt
| | - Taha I Zaghloul
- Department of Biotechnology, Institute of Graduate Studies and Research, Alexandria University, Alexandria 21526, Egypt
| | - Shaimaa K Mostafa
- Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy, Delta University for Science and Technology, Gamesa, Mansoura, Egypt
| | - Nazik A Elgindy
- Department of Pharmaceutics, Faculty of Pharmacy, Alexandria University, Egypt
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4
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Targeting anti-apoptotic pathways eliminates senescent melanocytes and leads to nevi regression. Nat Commun 2022; 13:7923. [PMID: 36564381 PMCID: PMC9789033 DOI: 10.1038/s41467-022-35657-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022] Open
Abstract
Human melanocytic nevi (moles) result from a brief period of clonal expansion of melanocytes. As a cellular defensive mechanism against oncogene-induced hyperplasia, nevus-resident melanocytes enter a senescent state of stable cell cycle arrest. Senescent melanocytes can persist for months in mice and years in humans with a risk to escape the senescent state and progress to melanoma. The mechanisms providing prolonged survival of senescent melanocytes remain poorly understood. Here, we show that senescent melanocytes in culture and in nevi express high level of the anti-apoptotic BCL-2 family member BCL-W but remain insensitive to the pan-BCL-2 inhibitor ABT-263. We demonstrate that resistance to ABT-263 is driven by mTOR-mediated enhanced translation of another anti-apoptotic member, MCL-1. Strikingly, the combination of ABT-263 and MCL-1 inhibitors results in synthetic lethality to senescent melanocytes, and its topical application sufficient to eliminate nevi in male mice. These data highlight the important role of redundant anti-apoptotic mechanisms for the survival advantage of senescent melanocytes, and the proof-of-concept for a non-invasive combination therapy for nevi removal.
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5
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Mohamed NV, Sirois J, Ramamurthy J, Mathur M, Lépine P, Deneault E, Maussion G, Nicouleau M, Chen CXQ, Abdian N, Soubannier V, Cai E, Nami H, Thomas RA, Wen D, Tabatabaei M, Beitel LK, Singh Dolt K, Karamchandani J, Stratton JA, Kunath T, Fon EA, Durcan TM. Midbrain organoids with an SNCA gene triplication model key features of synucleinopathy. Brain Commun 2021; 3:fcab223. [PMID: 34632384 PMCID: PMC8495137 DOI: 10.1093/braincomms/fcab223] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 08/06/2021] [Accepted: 08/16/2021] [Indexed: 02/05/2023] Open
Abstract
SNCA, the first gene associated with Parkinson's disease, encodes the α-synuclein protein, the predominant component within pathological inclusions termed Lewy bodies. The presence of Lewy bodies is one of the classical hallmarks found in the brain of patients with Parkinson's disease, and Lewy bodies have also been observed in patients with other synucleinopathies. However, the study of α-synuclein pathology in cells has relied largely on two-dimensional culture models, which typically lack the cellular diversity and complex spatial environment found in the brain. Here, to address this gap, we use three-dimensional midbrain organoids, differentiated from human-induced pluripotent stem cells derived from patients carrying a triplication of the SNCA gene and from CRISPR/Cas9 corrected isogenic control iPSCs. These human midbrain organoids recapitulate key features of α-synuclein pathology observed in the brains of patients with synucleinopathies. In particular, we find that SNCA triplication human midbrain organoids express elevated levels of α-synuclein and exhibit an age-dependent increase in α-synuclein aggregation, manifested by the presence of both oligomeric and phosphorylated forms of α-synuclein. These phosphorylated α-synuclein aggregates were found in both neurons and glial cells and their time-dependent accumulation correlated with a selective reduction in dopaminergic neuron numbers. Thus, human midbrain organoids from patients carrying SNCA gene multiplication can reliably model key pathological features of Parkinson's disease and provide a powerful system to study the pathogenesis of synucleinopathies.
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Affiliation(s)
- Nguyen-Vi Mohamed
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Julien Sirois
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Janani Ramamurthy
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Meghna Mathur
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Paula Lépine
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Eric Deneault
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Gilles Maussion
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Michael Nicouleau
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Carol X-Q Chen
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Narges Abdian
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Vincent Soubannier
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Eddie Cai
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Harris Nami
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Rhalena A Thomas
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Dingke Wen
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu 610063, China
| | - Mahdieh Tabatabaei
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada.,C-BIG Biorepository (C-BIG), Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Lenore K Beitel
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Karamjit Singh Dolt
- Centre for Regenerative Medicine, School of Biological Sciences, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Jason Karamchandani
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada.,C-BIG Biorepository (C-BIG), Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Jo Anne Stratton
- Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Tilo Kunath
- Centre for Regenerative Medicine, School of Biological Sciences, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Edward A Fon
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Thomas M Durcan
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
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6
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Mohamed NV, Mathur M, da Silva RV, Thomas RA, Lepine P, Beitel LK, Fon EA, Durcan TM. Generation of human midbrain organoids from induced pluripotent stem cells. ACTA ACUST UNITED AC 2021. [DOI: 10.12688/mniopenres.12816.2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The development of brain organoids represents a major technological advance in the stem cell field, a novel bridge between traditional 2D cultures and in vivo animal models. In particular, the development of midbrain organoids containing functional dopaminergic neurons producing neuromelanin granules, a by-product of dopamine synthesis, represents a potential new model for Parkinson’s disease. To generate human midbrain organoids, we introduce specific inductive cues, at defined timepoints, during the 3D culture process to drive the stem cells towards a midbrain fate. In this method paper, we describe a standardized protocol to generate human midbrain organoids (hMOs) from induced pluripotent stem cells (iPSCs). This protocol was developed to demonstrate how human iPSCs can be successfully differentiated into numerous, high quality midbrain organoids in one batch. We also describe adaptations for cryosectioning of fixed organoids for subsequent histological analysis.
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7
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Valdebran M, Kowalski EH, Kneiber D, Li J, Kim J, Amber KT. Digital Quantification of Epidermal Protein Expression in Paraffin-Embedded Tissue Using Immunohistochemistry. Methods Mol Biol 2020; 2109:75-82. [PMID: 31190272 DOI: 10.1007/7651_2019_244] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Current methods of assessing immunohistochemistry center on semiquantitative visual grading scales. More objective methods utilizing digital quantification offer superior precision and, presumably, higher confidence with image comparison. However, their cost often remains prohibitive, and there is little customizability to separate subsections of interest in the tissue. Here we describe a method using two open-source software programs to analyze the intensity and density of signals in immunohistochemistry-stained tissue sections that account for tissue heterogeneity and allow for direct comparison between two samples. This method allows for quantitative assessment of epidermal protein expression. We herein demonstrate this workflow using an epidermal stain tothymic stromal lymphopoietin.
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Affiliation(s)
- Manuel Valdebran
- Department of Dermatology, University of California Irvine, Irvine, CA, USA
| | - Eric H Kowalski
- Department of Dermatology, University of Illinois at Chicago, Chicago, IL, USA
| | - Diana Kneiber
- Department of Dermatology, University of Illinois at Chicago, Chicago, IL, USA
| | - Jing Li
- Department of Dermatology, University of California Irvine, Irvine, CA, USA
| | - Jeffrey Kim
- Department of Pathology, University of California Irvine, Irvine, CA, USA
| | - Kyle T Amber
- Department of Dermatology, University of Illinois at Chicago, Chicago, IL, USA.
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8
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Lee V, Gober MD, Bashir H, O'Day C, Blair IA, Mesaros C, Weng L, Huang A, Chen A, Tang R, Anagnos V, Li J, Roling S, Sagaityte E, Wang A, Lin C, Yeh C, Atillasoy C, Marshall C, Dentchev T, Ridky T, Seykora JT. Voriconazole enhances UV-induced DNA damage by inhibiting catalase and promoting oxidative stress. Exp Dermatol 2019; 29:29-38. [PMID: 31519066 DOI: 10.1111/exd.14038] [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: 01/27/2019] [Revised: 08/02/2019] [Accepted: 08/30/2019] [Indexed: 12/17/2022]
Abstract
Cutaneous squamous cell carcinoma (cSCC) is the second most common form of skin cancer and is associated with cumulative UV exposure. Studies have shown that prolonged voriconazole use promotes cSCC formation; however, the biological mechanisms responsible for the increased incidence remain unclear. Here, we show that voriconazole directly increases oxidative stress in human keratinocytes and promotes UV-induced DNA damage as determined by comet assay, 8-oxoguanine immunofluorescence and mass spectrometry. Voriconazole treatment of human keratinocytes potentiates UV-induced apoptosis and activation of the p38 MAP kinase and 53BP1 UV stress response pathways. The p38 MAP kinase activation promoted by voriconazole exposure can be mitigated by pretreating keratinocytes with N-acetylcysteine. Voriconazole increases oxidative stress in keratinocytes by directly inhibiting catalase leading to lower intracellular NADPH levels and the triazole moieties in voriconazole are critical for inhibiting catalase. Furthermore, voriconazole is shown to promote UV-induced dysplasia in an in vivo model. Together, these data demonstrate that voriconazole potentiates oxidative stress in UV-irradiated keratinocytes through catalase inhibition. Use of antioxidants may mitigate the pro-oncogenic effects of voriconazole.
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Affiliation(s)
- Vivian Lee
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Ophthalmology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Michael D Gober
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Hasan Bashir
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Ophthalmology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Conor O'Day
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Ian A Blair
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Clementina Mesaros
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Liwei Weng
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Andrew Huang
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Aaron Chen
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Rachel Tang
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Vince Anagnos
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - JiLon Li
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Sophie Roling
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Emilija Sagaityte
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Andrew Wang
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Chenyan Lin
- Department of Ophthalmology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Christopher Yeh
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Cem Atillasoy
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Christine Marshall
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Tzvete Dentchev
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Todd Ridky
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - John T Seykora
- Department of Dermatology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
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9
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Nagapan TS, Lim WN, Basri DF, Ghazali AR. Oral supplementation of L-glutathione prevents ultraviolet B-induced melanogenesis and oxidative stress in BALB/c mice. Exp Anim 2019; 68:541-548. [PMID: 31243189 PMCID: PMC6842793 DOI: 10.1538/expanim.19-0017] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Dietary antioxidant supplements such as L-glutathione have gained considerable attention
in dermatology and cosmeceutical fields. L-glutathione possesses antiaging,
antimelanogenic, antioxidant, and anticancer properties. This study aimed to investigate
the inhibitory effects of L-glutathione on melanogenesis activity and oxidative stress in
ultraviolet B (UVB)-irradiated BALB/c mice. Eighteen female BALB/c mice were randomly
divided into 3 groups: a control group (n=6), a group without UVB irradiation and
L-glutathione administration; a UVB irradiated group (n=6), a group irradiated with a UVB
dose of 250 mJ/cm2 for 3 min; and a treatment group (n=6), a group irradiated
with UVB and treated with 100 mg/kg of L-glutathione by oral gavage. Treatment was given
for 14 days, and UVB irradiation was given on days 9, 11, and 13. Oral L-glutathione
significantly (P<0.05) reduced lipid peroxidation and elevated
superoxide dismutase activity the and glutathione level. L-glutathione also inhibited
melanin content and tyrosinase activity significantly (P<0.05) as
compared with the UVB-irradiated group. Histopathological examination also showed that
L-glutathione reduced the deposition of melanin pigment in the basal layer of the
epidermis as compared with that in UVB-irradiated mice. All in all, the present study
demonstrated that L-glutathione has the potential to be developed as a photoprotection
agent against UVB-induced oxidative stress and melanogenesis.
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Affiliation(s)
- Tava Shelan Nagapan
- Programme of Biomedical Science, Centre of Health & Applied Sciences, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia
| | - Wenna Nallance Lim
- Programme of Biomedical Science, Centre of Health & Applied Sciences, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia
| | - Dayang Fredalina Basri
- Programme of Biomedical Science, Centre of Health & Applied Sciences, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia
| | - Ahmad Rohi Ghazali
- Programme of Biomedical Science, Centre of Health & Applied Sciences, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia
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10
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Mohamed NV, Mathur M, da Silva RV, Beitel LK, Fon EA, Durcan TM. Generation of human midbrain organoids from induced pluripotent stem cells. ACTA ACUST UNITED AC 2019. [DOI: 10.12688/mniopenres.12816.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The development of brain organoids represents a major technological advance in the stem cell field, a novel bridge between traditional 2D cultures and in vivo animal models. In particular, the development of midbrain organoids containing functional dopaminergic neurons producing neuromelanin granules, a by-product of dopamine synthesis, represents a potential new model for Parkinson’s disease. To generate human midbrain organoids, we introduce specific inductive cues, at defined timepoints, during the 3D culture process to drive the stem cells towards a midbrain fate. In this method paper, we describe a standardized protocol to generate human midbrain organoids (hMOs) from induced pluripotent stem cells (iPSCs). This protocol was developed to demonstrate how human iPSCs can be successfully differentiated into numerous, high quality midbrain organoids in one batch. We also describe adaptations for cryosectioning of fixed organoids for subsequent histological analysis.
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Nishiguchi MA, Spencer CA, Leung DH, Leung TH. Aging Suppresses Skin-Derived Circulating SDF1 to Promote Full-Thickness Tissue Regeneration. Cell Rep 2018; 24:3383-3392.e5. [PMID: 30257200 PMCID: PMC6261459 DOI: 10.1016/j.celrep.2018.08.054] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 07/10/2018] [Accepted: 08/17/2018] [Indexed: 02/08/2023] Open
Abstract
Physicians have observed that surgical wounds in the elderly heal with thinner scars than wounds in young patients. Understanding this phenomenon may reveal strategies for promoting scarless wound repair. We show that full-thickness skin wounds in aged but not young mice fully regenerate. Exposure of aged animals to blood from young mice by parabiosis counteracts this regenerative capacity. The secreted factor, stromal-derived factor 1 (SDF1), is expressed at higher levels in wounded skin of young mice. Genetic deletion of SDF1 in young skin enhanced tissue regeneration. In aged mice, enhancer of zeste homolog 2 (EZH2) and histone H3 lysine 27 trimethylation are recruited to the SDF1 promoter at higher levels, and pharmacologic inhibition of EZH2 restores SDF1 induction and prevents tissue regeneration. Similar age-dependent EZH2-mediated SDF1 suppression occurs in human skin. Our findings counter the current dogma that tissue function invariably declines with age and suggest new therapeutic strategies in regenerative medicine.
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Affiliation(s)
- Mailyn A Nishiguchi
- Department of Dermatology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | - Casey A Spencer
- Department of Dermatology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | - Denis H Leung
- School of Economics, Singapore Management University, Singapore 188065, Singapore
| | - Thomas H Leung
- Department of Dermatology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA; Corporal Michael Crescenz Veterans Affairs Medical Center, Philadelphia, PA 19104, USA; Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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12
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Lysosomes Support the Degradation, Signaling, and Mitochondrial Metabolism Necessary for Human Epidermal Differentiation. J Invest Dermatol 2018. [PMID: 29526763 DOI: 10.1016/j.jid.2018.02.035] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Keratinocytes undergo significant structural remodeling during epidermal differentiation, including a broad transformation of the proteome coupled with a reduction in total cellular biomass. This suggests that intracellular digestion of proteins and organelles is necessary for keratinocyte differentiation. Here, we use both genetic and pharmacologic approaches to demonstrate that autophagy and lysosomal functions are required for keratinocyte differentiation in organotypic human skin. Lysosomal activity was required for mechanistic target of rapamycin signaling and mitochondrial oxidative metabolism. In turn, mitochondrial reactive oxygen species, produced as a natural byproduct of oxidative phosphorylation, were necessary for keratinocyte differentiation. Finally, treatment with exogenous reactive oxygen species rescued the differentiation defect in lysosome-inhibited keratinocytes. These findings highlight a reciprocal relationship between lysosomes and mitochondria, in which lysosomes support mitochondrial metabolism and the associated production of mitochondrial reactive oxygen species. The mitochondrial reactive oxygen species released to the cytoplasm in suprabasal keratinocytes triggers autophagy and lysosome-mediated degradation necessary for epidermal differentiation. As defective lysosome-dependent autophagy is associated with common skin diseases including psoriasis and atopic dermatitis, a better understanding of the role of lysosomes in epidermal homeostasis may guide future therapeutic strategies.
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13
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Natale CA, Li J, Zhang J, Dahal A, Dentchev T, Stanger BZ, Ridky TW. Activation of G protein-coupled estrogen receptor signaling inhibits melanoma and improves response to immune checkpoint blockade. eLife 2018; 7. [PMID: 29336307 PMCID: PMC5770157 DOI: 10.7554/elife.31770] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 12/05/2017] [Indexed: 12/30/2022] Open
Abstract
Female sex and history of prior pregnancies are associated with favorable melanoma outcomes. Here, we show that much of the melanoma protective effect likely results from estrogen signaling through the G protein-coupled estrogen receptor (GPER) on melanocytes. Selective GPER activation in primary melanocytes and melanoma cells induced long-term changes that maintained a more differentiated cell state as defined by increased expression of well-established melanocyte differentiation antigens, increased pigment production, decreased proliferative capacity, and decreased expression of the oncodriver and stem cell marker c-Myc. GPER signaling also rendered melanoma cells more vulnerable to immunotherapy. Systemically delivered GPER agonist was well tolerated, and cooperated with immune checkpoint blockade in melanoma-bearing mice to dramatically extend survival, with up to half of mice clearing their tumor. Complete responses were associated with immune memory that protected against tumor rechallenge. GPER may be a useful, pharmacologically accessible target for melanoma.
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Affiliation(s)
- Christopher A Natale
- Perelman School of Medicine, Department of Dermatology, University of Pennsylvania, Philadelphia, United States
| | - Jinyang Li
- Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Junqian Zhang
- Perelman School of Medicine, Department of Dermatology, University of Pennsylvania, Philadelphia, United States
| | - Ankit Dahal
- Perelman School of Medicine, Department of Dermatology, University of Pennsylvania, Philadelphia, United States
| | - Tzvete Dentchev
- Perelman School of Medicine, Department of Dermatology, University of Pennsylvania, Philadelphia, United States
| | - Ben Z Stanger
- Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Todd W Ridky
- Perelman School of Medicine, Department of Dermatology, University of Pennsylvania, Philadelphia, United States
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14
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Zhang H, Ericsson M, Virtanen M, Weström S, Wählby C, Vahlquist A, Törmä H. Quantitative image analysis of protein expression and colocalisation in skin sections. Exp Dermatol 2018; 27:196-199. [DOI: 10.1111/exd.13457] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/25/2017] [Indexed: 12/01/2022]
Affiliation(s)
- Hanqian Zhang
- Department of Medical Sciences, Dermatology and Venereology; Uppsala University; Uppsala Sweden
| | - Maja Ericsson
- Department of Medical Sciences, Dermatology and Venereology; Uppsala University; Uppsala Sweden
| | - Marie Virtanen
- Department of Medical Sciences, Dermatology and Venereology; Uppsala University; Uppsala Sweden
| | - Simone Weström
- Department of Medical Sciences, Dermatology and Venereology; Uppsala University; Uppsala Sweden
| | - Carolina Wählby
- Division of Visual Information and Interaction; Department of Information Technology; SciLifeLab; Uppsala University; Uppsala Sweden
| | - Anders Vahlquist
- Department of Medical Sciences, Dermatology and Venereology; Uppsala University; Uppsala Sweden
| | - Hans Törmä
- Department of Medical Sciences, Dermatology and Venereology; Uppsala University; Uppsala Sweden
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15
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Orfanidis K, Wäster P, Lundmark K, Rosdahl I, Öllinger K. Evaluation of tubulin β-3 as a novel senescence-associated gene in melanocytic malignant transformation. Pigment Cell Melanoma Res 2017; 30:243-254. [PMID: 28024114 DOI: 10.1111/pcmr.12572] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 12/17/2016] [Indexed: 12/22/2022]
Abstract
Malignant melanoma might develop from melanocytic nevi in which the growth-arrested state has been broken. We analyzed the gene expression of young and senescent human melanocytes in culture and compared the gene expression data with a dataset from nevi and melanomas. A concordant altered gene expression was identified in 84 genes when comparing the growth-arrested samples with proliferating samples. TUBB3, which encodes the microtubule protein tubulin β-3, showed a decreased expression in senescent melanocytes and nevi and was selected for further studies. Depletion of tubulin β-3 caused accumulation of cells in the G2/M phase and decreased proliferation and migration. Immunohistochemical assessment of tubulin β-3 in benign lesions revealed strong staining in the superficial part of the intradermal components, which faded with depth. In contrast, primary melanomas exhibited staining without gradient in a disordered pattern and strong staining of the invasive front. Our results describe an approach to find clinically useful diagnostic biomarkers to more precisely identify cutaneous malignant melanoma and present tubulin β-3 as a candidate marker.
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Affiliation(s)
- Kyriakos Orfanidis
- Department of Dermatology and Venereology, Linköping University, Linköping, Sweden.,Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Petra Wäster
- Experimental Pathology, Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Katarzyna Lundmark
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.,Department of Clinical Pathology and Clinical Genetics, Linköping University, Linköping, Sweden
| | - Inger Rosdahl
- Department of Dermatology and Venereology, Linköping University, Linköping, Sweden.,Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Karin Öllinger
- Experimental Pathology, Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
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16
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Lai C, Healy E. The Warthin-Starry stain for detection of cutaneous melanin: more than a historical curiosity. Exp Dermatol 2016; 25:763-4. [DOI: 10.1111/exd.13101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/20/2016] [Indexed: 01/22/2023]
Affiliation(s)
- Chester Lai
- Dermatopharmacology; Sir Henry Wellcome Laboratories; Faculty of Medicine; University of Southampton; Southampton UK
- Dermatology; University Hospital Southampton NHS Foundation Trust; Southampton UK
| | - Eugene Healy
- Dermatopharmacology; Sir Henry Wellcome Laboratories; Faculty of Medicine; University of Southampton; Southampton UK
- Dermatology; University Hospital Southampton NHS Foundation Trust; Southampton UK
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17
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Natale CA, Duperret EK, Zhang J, Sadeghi R, Dahal A, O'Brien KT, Cookson R, Winkler JD, Ridky TW. Sex steroids regulate skin pigmentation through nonclassical membrane-bound receptors. eLife 2016; 5. [PMID: 27115344 PMCID: PMC4863824 DOI: 10.7554/elife.15104] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 04/11/2016] [Indexed: 12/15/2022] Open
Abstract
The association between pregnancy and altered cutaneous pigmentation has been documented for over two millennia, suggesting that sex hormones play a role in regulating epidermal melanocyte (MC) homeostasis. Here we show that physiologic estrogen (17β-estradiol) and progesterone reciprocally regulate melanin synthesis. This is intriguing given that we also show that normal primary human MCs lack classical estrogen or progesterone receptors (ER or PR). Utilizing both genetic and pharmacologic approaches, we establish that sex steroid effects on human pigment synthesis are mediated by the membrane-bound, steroid hormone receptors G protein-coupled estrogen receptor (GPER), and progestin and adipoQ receptor 7 (PAQR7). Activity of these receptors was activated or inhibited by synthetic estrogen or progesterone analogs that do not bind to ER or PR. As safe and effective treatment options for skin pigmentation disorders are limited, these specific GPER and PAQR7 ligands may represent a novel class of therapeutics. DOI:http://dx.doi.org/10.7554/eLife.15104.001 Factors controlling pigment production in skin are complex and poorly understood. Cells called melanocytes produce a pigment called melanin, which makes the skin darker. It has been known for a long time that skin color often changes during pregnancy, which suggests that sex hormones may be involved. However, the specific hormones and signaling mechanisms responsible for the changes have remained largely undefined. Estrogen and progesterone are two of the main female sex hormones. Natale et al. now show that estrogen increases pigment production in human melanocytes, and progesterone decreases it. For hormones to signal to cells, they must bind to and activate particular receptor proteins. Further investigation by Natale et al. revealed that estrogen and progesterone regulate pigment production by binding to receptors that belong to a family called G protein-coupled receptors. These receptors can signal rapidly once activated by sex hormones, and may serve as therapeutic targets for treating pigmentation disorders. Skin diseases that cause inflammation often also cause changes in skin color. Natale et al. noticed several other G protein-coupled receptors that are likely to control pigmentation through similar mechanisms. Future analyses of the roles that these other receptors perform in melanocytes may therefore reveal how inflammation-based pigmentation changes occur. DOI:http://dx.doi.org/10.7554/eLife.15104.002
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Affiliation(s)
- Christopher A Natale
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Elizabeth K Duperret
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Junqian Zhang
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Rochelle Sadeghi
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Ankit Dahal
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Kevin Tyler O'Brien
- Department of Chemistry, University of Pennsylvania, Philadelphia, United States
| | - Rosa Cookson
- Department of Chemistry, University of Pennsylvania, Philadelphia, United States
| | - Jeffrey D Winkler
- Department of Chemistry, University of Pennsylvania, Philadelphia, United States
| | - Todd W Ridky
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
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18
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Sanzari JK, Diffenderfer ES, Hagan S, Billings PC, Gridley DS, Seykora JT, Kennedy AR, Cengel KA. Dermatopathology effects of simulated solar particle event radiation exposure in the porcine model. LIFE SCIENCES IN SPACE RESEARCH 2015; 6:21-8. [PMID: 26256624 PMCID: PMC4531259 DOI: 10.1016/j.lssr.2015.06.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 06/11/2015] [Accepted: 06/12/2015] [Indexed: 06/04/2023]
Abstract
The space environment exposes astronauts to risks of acute and chronic exposure to ionizing radiation. Of particular concern is possible exposure to ionizing radiation from a solar particle event (SPE). During an SPE, magnetic disturbances in specific regions of the Sun result in the release of intense bursts of ionizing radiation, primarily consisting of protons that have a highly variable energy spectrum. Thus, SPE events can lead to significant total body radiation exposures to astronauts in space vehicles and especially while performing extravehicular activities. Simulated energy profiles suggest that SPE radiation exposures are likely to be highest in the skin. In the current report, we have used our established miniature pig model system to evaluate the skin toxicity of simulated SPE radiation exposures that closely resemble the energy and fluence profile of the September, 1989 SPE using either conventional radiation (electrons) or proton simulated SPE radiation. Exposure of animals to electron or proton radiation led to dose-dependent increases in epidermal pigmentation, the presence of necrotic keratinocytes at the dermal-epidermal boundary and pigment incontinence, manifested by the presence of melanophages in the derm is upon histological examination. We also observed epidermal hyperplasia and a reduction in vascular density at 30 days following exposure to electron or proton simulated SPE radiation. These results suggest that the doses of electron or proton simulated SPE radiation results in significant skin toxicity that is quantitatively and qualitatively similar. Radiation-induced skin damage is often one of the first clinical signs of both acute and non-acute radiation injury where infection may occur, if not treated. In this report, histopathology analyses of acute radiation-induced skin injury are discussed.
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Affiliation(s)
- Jenine K Sanzari
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Eric S Diffenderfer
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sarah Hagan
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Paul C Billings
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Daila S Gridley
- Department of Radiation Medicine, Radiation Research Laboratories, Loma Linda University and Medical Center, Loma Linda, CA 92354, USA
| | - John T Seykora
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ann R Kennedy
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Keith A Cengel
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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