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Veronese S, Picelli A, Zoccatelli A, Amuso D, Amore R, Smania N, Frisone A, Sbarbati A, Scarano A. Morphological characterization of two dermal and hypodermal alterations in an adult man: surgical scar vs. stretch mark. J Ultrasound 2024; 27:857-862. [PMID: 39305402 PMCID: PMC11496462 DOI: 10.1007/s40477-024-00956-y] [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: 06/14/2024] [Accepted: 08/20/2024] [Indexed: 10/23/2024] Open
Abstract
Scars and stretch marks are extremely common. For scars, evidence of alterations of the dermal and hypodermic layers is known, while for stretch marks, less data are available, and they are considered purely aesthetic conditions. The intra- and inter-subject variability of the skin makes the comparison between these two particularly complex. This study presents the case of a 54-year-old man who had both stretch marks and a surgical scar on his abdomen. We performed ultrasound and elastosonographic investigations for both to analyse the structural alteration of the skin and subcutaneous layers. Their structures were also compared to the structure of intact skin. The two skin conditions appeared substantially morphologically different and different from intact skin. The alterations detected, particularly of the connective structures, allow us to state that both scars and stretch marks are alterations of both the dermis and the hypodermis and stretch marks differ from scars.
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Affiliation(s)
- Sheila Veronese
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, 37134, Verona, Italy
| | - Alessandro Picelli
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, 37134, Verona, Italy
| | - Andrea Zoccatelli
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, 37134, Verona, Italy
| | - Domenico Amuso
- Department of Innovative Technology in Medicine and Dentistry, University of Chieti-Pescara, Chieti, Italy
| | - Roberto Amore
- Department of Innovative Technology in Medicine and Dentistry, University of Chieti-Pescara, Chieti, Italy
| | - Nicola Smania
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, 37134, Verona, Italy
| | - Alessio Frisone
- Master Course in Aesthetic Medicine, University of Chieti-Pescara, Via Dei Vestini 31, 66100, Chieti, Italy
| | - Andrea Sbarbati
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, 37134, Verona, Italy
| | - Antonio Scarano
- Master Course in Aesthetic Medicine, University of Chieti-Pescara, Via Dei Vestini 31, 66100, Chieti, Italy.
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2
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Briganti S, Mosca S, Di Nardo A, Flori E, Ottaviani M. New Insights into the Role of PPARγ in Skin Physiopathology. Biomolecules 2024; 14:728. [PMID: 38927131 PMCID: PMC11201613 DOI: 10.3390/biom14060728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Revised: 06/17/2024] [Accepted: 06/18/2024] [Indexed: 06/28/2024] Open
Abstract
Peroxisome proliferator-activated receptor gamma (PPARγ) is a transcription factor expressed in many tissues, including skin, where it is essential for maintaining skin barrier permeability, regulating cell proliferation/differentiation, and modulating antioxidant and inflammatory responses upon ligand binding. Therefore, PPARγ activation has important implications for skin homeostasis. Over the past 20 years, with increasing interest in the role of PPARs in skin physiopathology, considerable effort has been devoted to the development of PPARγ ligands as a therapeutic option for skin inflammatory disorders. In addition, PPARγ also regulates sebocyte differentiation and lipid production, making it a potential target for inflammatory sebaceous disorders such as acne. A large number of studies suggest that PPARγ also acts as a skin tumor suppressor in both melanoma and non-melanoma skin cancers, but its role in tumorigenesis remains controversial. In this review, we have summarized the current state of research into the role of PPARγ in skin health and disease and how this may provide a starting point for the development of more potent and selective PPARγ ligands with a low toxicity profile, thereby reducing unwanted side effects.
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Affiliation(s)
| | | | | | - Enrica Flori
- Laboratory of Cutaneous Physiopathology and Integrated Center of Metabolomics Research, San Gallicano Dermatological Institute, IRCCS, 00144 Rome, Italy; (S.B.); (S.M.); (A.D.N.); (M.O.)
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3
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Feghaly I, Kourie H, Moubarak M, Chouery E, Mehawej C, Jalkh N, Atallah D. Genetic profile of borderline ovarian tumors in the Lebanese population by whole-exome sequencing. Int J Gynaecol Obstet 2023; 162:1027-1032. [PMID: 37185951 DOI: 10.1002/ijgo.14805] [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: 07/17/2022] [Revised: 03/23/2023] [Accepted: 03/31/2023] [Indexed: 05/17/2023]
Abstract
OBJECTIVE To assess the molecular profile of borderline ovarian tumors (BOT) in the Lebanese population by whole-exome sequencing and to correlate the results with the patients' clinical profiles. METHODS We included in this retrospective study 33 tumors belonging to 32 Lebanese women presenting with BOT, diagnosed at Hôtel Dieu de France. A total of 234 genes involved in different germinal and somatic types of cancer were analyzed using next-generation sequencing. RESULTS Molecular analysis of these tumors allowed us to detect mutations in genes involved in the mitogen-activated protein kinase cascade in 57.58% of BOT and to identify variants affecting the DNA repair mechanism in 63.89% of samples. Furthermore, our initial analysis revealed an association between defects in DNA double-strand break repair and the occurrence of mucinous BOT, in 75% of the cases. CONCLUSION This study reports the molecular profiles of BOT in the Lebanese population and compares them to the literature. This is the first study associating the DNA repair pathway to BOT.
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Affiliation(s)
- Iman Feghaly
- Department of Obstetrics and Gynecology, Faculty of Medicine, Saint Joseph University of Beirut, Beirut, Lebanon
| | - Hampig Kourie
- Hematology-Oncology Department, Faculty of Medicine, Saint Joseph University of Beirut, Beirut, Lebanon
| | - Malak Moubarak
- Department of Obstetrics and Gynecology, Faculty of Medicine, Saint Joseph University of Beirut, Beirut, Lebanon
- Department of Gynecology and Gynecological Oncology, Kliniken Essen Mitte, Essen, Germany
| | - Eliane Chouery
- Medical Genetics Unit, Faculty of Medicine, Saint Joseph University of Beirut, Beirut, Lebanon
- Department of Human Genetics, Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos, Lebanon
| | - Cybel Mehawej
- Medical Genetics Unit, Faculty of Medicine, Saint Joseph University of Beirut, Beirut, Lebanon
- Department of Human Genetics, Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos, Lebanon
| | - Nadine Jalkh
- Medical Genetics Unit, Faculty of Medicine, Saint Joseph University of Beirut, Beirut, Lebanon
| | - David Atallah
- Department of Obstetrics and Gynecology, Faculty of Medicine, Saint Joseph University of Beirut, Beirut, Lebanon
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Cardinali G, Kovacs D, Mosca S, Bellei B, Flori E, Morrone A, Mileo AM, Maresca V. The αMSH-Dependent PI3K Pathway Supports Energy Metabolism, via Glucose Uptake, in Melanoma Cells. Cells 2023; 12:cells12071099. [PMID: 37048170 PMCID: PMC10093374 DOI: 10.3390/cells12071099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 03/29/2023] [Accepted: 04/04/2023] [Indexed: 04/14/2023] Open
Abstract
Stimulation of melanocytes and murine melanoma cells with αMSH plus the PI3K inhibitor LY294002 resulted in ROS increase, oxidative DNA damage, and pigment retention. We performed cellular and molecular biology assays (Western blot, FACS, immunofluorescence analysis, scratch assay) on murine and human melanoma cells. Treatment with αMSH plus LY294002 altered cortical actin architecture. Given that cytoskeleton integrity requires energy, we next evaluated ATP levels and we observed a drop in ATP after exposure to αMSH plus LY294002. To evaluate if the αMSH-activated PI3K pathway could modulate energy metabolism, we focused on glucose uptake by analyzing the expression of the Glut-1 glucose translocator. Compared with cells treated with αMSH alone, those exposed to combined treatment showed a reduction of Glut-1 on the plasma membrane. This metabolic alteration was associated with changes in mitochondrial mass. A significant decrease of the cell migratory potential was also observed. We demonstrated that the αMSH-dependent PI3K pathway acts as a regulator of energy metabolism via glucose uptake, influencing the actin cytoskeleton, which is involved in melanosome release and cell motility. Hence, these results could constitute the basis for innovative therapeutical strategies.
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Affiliation(s)
- Giorgia Cardinali
- Laboratory of Cutaneous Physiopathology, San Gallicano Dermatological Institute, IRCCS, 00144 Rome, Italy
| | - Daniela Kovacs
- Laboratory of Cutaneous Physiopathology, San Gallicano Dermatological Institute, IRCCS, 00144 Rome, Italy
| | - Sarah Mosca
- Laboratory of Cutaneous Physiopathology, San Gallicano Dermatological Institute, IRCCS, 00144 Rome, Italy
| | - Barbara Bellei
- Laboratory of Cutaneous Physiopathology, San Gallicano Dermatological Institute, IRCCS, 00144 Rome, Italy
| | - Enrica Flori
- Laboratory of Cutaneous Physiopathology, San Gallicano Dermatological Institute, IRCCS, 00144 Rome, Italy
| | - Aldo Morrone
- Laboratory of Cutaneous Physiopathology, San Gallicano Dermatological Institute, IRCCS, 00144 Rome, Italy
| | - Anna Maria Mileo
- Tumor Immunology and Immunotherapy Unit, Department of Research Advanced Diagnostic and Technological Innovation, Regina Elena National Cancer Institute, IRCCS, 00144 Rome, Italy
| | - Vittoria Maresca
- Laboratory of Cutaneous Physiopathology, San Gallicano Dermatological Institute, IRCCS, 00144 Rome, Italy
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5
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Consumer Behavior, Skin Phototype, Sunscreens, and Tools for Photoprotection: A Review. COSMETICS 2023. [DOI: 10.3390/cosmetics10020039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
Abstract
Sunscreens and photoprotection tools along with consumer habits and behaviors, can mitigate the skin damage caused by excessive solar radiation. For example, protecting oneself in the shade, avoiding inadequate sun exposure at times of higher incidence of UVB radiation (between 10:00 a.m. and 4:00 p.m.), wearing clothes with sun protection factors, applying sunscreens at the correct amounts and intervals, and wearing glasses with anti-UVA and UVB lenses are effective measures for protecting an individual. Therefore, the objective of this review was to highlight the importance of photoprotection for all skin phototypes, as skin cancer is a worldwide public health problem. In this review of the scientific literature on the Scopus platform between 2015 and 2022, we addressed the most common behaviors among different individuals and their phototypes, the importance of clarifying population habits against solar radiation, and the use of sunscreens and photoprotection tools to provide advice on healthy and safe sun exposure.
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Zouboulis CC, Coenye T, He L, Kabashima K, Kobayashi T, Niemann C, Nomura T, Oláh A, Picardo M, Quist SR, Sasano H, Schneider MR, Törőcsik D, Wong SY. Sebaceous immunobiology - skin homeostasis, pathophysiology, coordination of innate immunity and inflammatory response and disease associations. Front Immunol 2022; 13:1029818. [PMID: 36439142 PMCID: PMC9686445 DOI: 10.3389/fimmu.2022.1029818] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Accepted: 10/17/2022] [Indexed: 08/01/2023] Open
Abstract
This review presents several aspects of the innovative concept of sebaceous immunobiology, which summarizes the numerous activities of the sebaceous gland including its classical physiological and pathophysiological tasks, namely sebum production and the development of seborrhea and acne. Sebaceous lipids, which represent 90% of the skin surface lipids in adolescents and adults, are markedly involved in the skin barrier function and perifollicular and dermal innate immune processes, leading to inflammatory skin diseases. Innovative experimental techniques using stem cell and sebocyte models have clarified the roles of distinct stem cells in sebaceous gland physiology and sebocyte function control mechanisms. The sebaceous gland represents an integral part of the pilosebaceous unit and its status is connected to hair follicle morphogenesis. Interestingly, professional inflammatory cells contribute to sebocyte differentiation and homeostasis, whereas the regulation of sebaceous gland function by immune cells is antigen-independent. Inflammation is involved in the very earliest differentiation changes of the pilosebaceous unit in acne. Sebocytes behave as potent immune regulators, integrating into the innate immune responses of the skin. Expressing inflammatory mediators, sebocytes also contribute to the polarization of cutaneous T cells towards the Th17 phenotype. In addition, the immune response of the perifollicular infiltrate depends on factors produced by the sebaceous glands, mostly sebaceous lipids. Human sebocytes in vitro express functional pattern recognition receptors, which are likely to interact with bacteria in acne pathogenesis. Sex steroids, peroxisome proliferator-activated receptor ligands, neuropeptides, endocannabinoids and a selective apoptotic process contribute to a complex regulation of sebocyte-induced immunological reaction in numerous acquired and congenital skin diseases, including hair diseases and atopic dermatitis.
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Affiliation(s)
- Christos C. Zouboulis
- Departments of Dermatology, Venereology, Allergology and Immunology, Dessau Medical Center, Brandenburg Medical School Theodor Fontane and Faculty of Health Sciences Brandenburg, Dessau, Germany
| | - Tom Coenye
- Laboratory of Pharmaceutical Microbiology, Ghent University, Ghent, Belgium
| | - Li He
- Department of Dermatology, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Kenji Kabashima
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Tetsuro Kobayashi
- Laboratory for Innate Immune Systems, RIKEN Center for Integrative Medical Sciences (IMS), Yokohama, Kanagawa, Japan
| | - Catherin Niemann
- Center for Molecular Medicine Cologne, CMMC Research Institute, University of Cologne, Cologne, Germany
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany
| | - Takashi Nomura
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Attila Oláh
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Mauro Picardo
- San Gallicano Dermatologic Institute, IRCCS, Rome, Italy
| | - Sven R. Quist
- Department of Dermatology, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - Hironobu Sasano
- Department of Pathology, Tohoku University School of Medicine, Sendai, Japan
| | - Marlon R. Schneider
- Institute of Veterinary Physiology, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany
| | - Daniel Törőcsik
- Department of Dermatology, Faculty of Medicine, University of Debrecen and ELKH-DE Allergology Research Group, Debrecen, Hungary
| | - Sunny Y. Wong
- Departments of Dermatology and Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
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7
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Marcovici I, Coricovac D, Pinzaru I, Macasoi IG, Popescu R, Chioibas R, Zupko I, Dehelean CA. Melanin and Melanin-Functionalized Nanoparticles as Promising Tools in Cancer Research-A Review. Cancers (Basel) 2022; 14:1838. [PMID: 35406610 PMCID: PMC8998143 DOI: 10.3390/cancers14071838] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 03/24/2022] [Accepted: 04/01/2022] [Indexed: 12/25/2022] Open
Abstract
Cancer poses an ongoing global challenge, despite the substantial progress made in the prevention, diagnosis, and treatment of the disease. The existing therapeutic methods remain limited by undesirable outcomes such as systemic toxicity and lack of specificity or long-term efficacy, although innovative alternatives are being continuously investigated. By offering a means for the targeted delivery of therapeutics, nanotechnology (NT) has emerged as a state-of-the-art solution for augmenting the efficiency of currently available cancer therapies while combating their drawbacks. Melanin, a polymeric pigment of natural origin that is widely spread among many living organisms, became a promising candidate for NT-based cancer treatment owing to its unique physicochemical properties (e.g., high biocompatibility, redox behavior, light absorption, chelating ability) and innate antioxidant, photoprotective, anti-inflammatory, and antitumor effects. The latest research on melanin and melanin-like nanoparticles has extended considerably on many fronts, allowing not only efficient cancer treatments via both traditional and modern methods, but also early disease detection and diagnosis. The current paper provides an updated insight into the applicability of melanin in cancer therapy as antitumor agent, molecular target, and delivery nanoplatform.
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Affiliation(s)
- Iasmina Marcovici
- Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania; (I.M.); (D.C.); (I.G.M.); (C.A.D.)
- Research Center for Pharmaco-Toxicological Evaluations, Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania
| | - Dorina Coricovac
- Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania; (I.M.); (D.C.); (I.G.M.); (C.A.D.)
- Research Center for Pharmaco-Toxicological Evaluations, Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania
| | - Iulia Pinzaru
- Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania; (I.M.); (D.C.); (I.G.M.); (C.A.D.)
- Research Center for Pharmaco-Toxicological Evaluations, Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania
| | - Ioana Gabriela Macasoi
- Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania; (I.M.); (D.C.); (I.G.M.); (C.A.D.)
- Research Center for Pharmaco-Toxicological Evaluations, Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania
| | - Roxana Popescu
- Faculty of Medicine, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania; (R.P.); (R.C.)
- Research Center ANAPATMOL, Faculty of Medicine, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania
| | - Raul Chioibas
- Faculty of Medicine, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania; (R.P.); (R.C.)
| | - Istvan Zupko
- Faculty of Pharmacy, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary;
| | - Cristina Adriana Dehelean
- Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania; (I.M.); (D.C.); (I.G.M.); (C.A.D.)
- Research Center for Pharmaco-Toxicological Evaluations, Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy Timisoara, Eftimie Murgu Square No. 2, 300041 Timisoara, Romania
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Abstract
Melanoma is the most lethal skin cancer that originates from the malignant transformation of melanocytes. Although melanoma has long been regarded as a cancerous malignancy with few therapeutic options, increased biological understanding and unprecedented innovations in therapies targeting mutated driver genes and immune checkpoints have substantially improved the prognosis of patients. However, the low response rate and inevitable occurrence of resistance to currently available targeted therapies have posed the obstacle in the path of melanoma management to obtain further amelioration. Therefore, it is necessary to understand the mechanisms underlying melanoma pathogenesis more comprehensively, which might lead to more substantial progress in therapeutic approaches and expand clinical options for melanoma therapy. In this review, we firstly make a brief introduction to melanoma epidemiology, clinical subtypes, risk factors, and current therapies. Then, the signal pathways orchestrating melanoma pathogenesis, including genetic mutations, key transcriptional regulators, epigenetic dysregulations, metabolic reprogramming, crucial metastasis-related signals, tumor-promoting inflammatory pathways, and pro-angiogenic factors, have been systemically reviewed and discussed. Subsequently, we outline current progresses in therapies targeting mutated driver genes and immune checkpoints, as well as the mechanisms underlying the treatment resistance. Finally, the prospects and challenges in the development of melanoma therapy, especially immunotherapy and related ongoing clinical trials, are summarized and discussed.
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Affiliation(s)
- Weinan Guo
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, No. 127 of West Changle Road, 710032, Xi'an, Shaanxi, China
| | - Huina Wang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, No. 127 of West Changle Road, 710032, Xi'an, Shaanxi, China
| | - Chunying Li
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, No. 127 of West Changle Road, 710032, Xi'an, Shaanxi, China.
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Guida S, Guida G, Goding CR. MC1R Functions, Expression, and Implications for Targeted Therapy. J Invest Dermatol 2021; 142:293-302.e1. [PMID: 34362555 DOI: 10.1016/j.jid.2021.06.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 06/14/2021] [Accepted: 06/17/2021] [Indexed: 12/23/2022]
Abstract
The G protein-coupled MC1R is expressed in melanocytes and has a pivotal role in human skin pigmentation, with reduced function in human genetic variants exhibiting a red hair phenotype and increased melanoma predisposition. Beyond its role in pigmentation, MC1R is increasingly recognized as promoting UV-induced DNA damage repair. Consequently, there is mounting interest in targeting MC1R for therapeutic benefit. However, whether MC1R expression is restricted to melanocytes or is more widely expressed remains a matter of debate. In this paper, we review MC1R function and highlight that unbiased analysis suggests that its expression is restricted to melanocytes, granulocytes, and the brain.
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Affiliation(s)
- Stefania Guida
- Dermatology Unit, Surgical, Medical and Dental Department of Morphological Sciences Related to Transplant, Oncological and Regenerative Medicine, University of Modena and Reggio Emilia, Modena, Italy.
| | - Gabriella Guida
- Molecular Biology Section, Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, Bari, Italy
| | - Colin Ronald Goding
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
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10
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Ponsonby AL. Reflection on modern methods: building causal evidence within high-dimensional molecular epidemiological studies of moderate size. Int J Epidemiol 2021; 50:1016-1029. [PMID: 33594409 DOI: 10.1093/ije/dyaa174] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/17/2020] [Indexed: 12/29/2022] Open
Abstract
This commentary provides a practical perspective on epidemiological analysis within a single high-dimensional study of moderate size to consider a causal question. In this setting, non-causal confounding is important. This occurs when a factor is a determinant of outcome and the underlying association between exposure and the factor is non-causal. That is, the association arises due to chance, confounding or other bias rather than reflecting that exposure and the factor are causally related. In particular, the influence of technical processing factors must be accounted for by pre-processing measures to remove artefact or to control for these factors such as batch run. Work steps include the evaluation of alternative non-causal explanations for observed exposure-disease associations and strategies to obtain the highest level of causal inference possible within the study. A systematic approach is required to work through a question set and obtain insights on not only the exposure-disease association but also the multifactorial causal structure of the underlying data where possible. The appropriate inclusion of molecular findings will enhance the quest to better understand multifactorial disease causation in modern observational epidemiological studies.
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11
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Manganelli M, Guida S, Ferretta A, Pellacani G, Porcelli L, Azzariti A, Guida G. Behind the Scene: Exploiting MC1R in Skin Cancer Risk and Prevention. Genes (Basel) 2021; 12:1093. [PMID: 34356109 PMCID: PMC8305013 DOI: 10.3390/genes12071093] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/14/2021] [Accepted: 07/16/2021] [Indexed: 02/06/2023] Open
Abstract
Melanoma and non-melanoma skin cancers (NMSCs) are the most frequent cancers of the skin in white populations. An increased risk in the development of skin cancers has been associated with the combination of several environmental factors (i.e., ultraviolet exposure) and genetic background, including melanocortin-1 receptor (MC1R) status. In the last few years, advances in the diagnosis of skin cancers provided a great impact on clinical practice. Despite these advances, NMSCs are still the most common malignancy in humans and melanoma still shows a rising incidence and a poor prognosis when diagnosed at an advanced stage. Efforts are required to underlie the genetic and clinical heterogeneity of melanoma and NMSCs, leading to an optimization of the management of affected patients. The clinical implications of the impact of germline MC1R variants in melanoma and NMSCs' risk, together with the additional risk conferred by somatic mutations in other peculiar genes, as well as the role of MC1R screening in skin cancers' prevention will be addressed in the current review.
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Affiliation(s)
- Michele Manganelli
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari-“Aldo Moro”, 70125 Bari, Italy; (M.M.); (A.F.)
- DMMT-Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy
| | - Stefania Guida
- Department of Surgical-Medical-Dental and Morphological Science with Interest Transplant-Oncological and Regenerative Medicine, University of Modena and Reggio Emilia, 41124 Modena, Italy;
| | - Anna Ferretta
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari-“Aldo Moro”, 70125 Bari, Italy; (M.M.); (A.F.)
| | - Giovanni Pellacani
- Department of Clinical Internal, Anesthesiological and Cardiovascular Sciences, Dermatology Clinic, Sapienza University of Rome, 00161 Rome, Italy;
| | - Letizia Porcelli
- Laboratory of Experimental Pharmacology, IRCCS Istituto Tumori Giovanni Paolo II, 70124 Bari, Italy; (L.P.); (A.A.)
| | - Amalia Azzariti
- Laboratory of Experimental Pharmacology, IRCCS Istituto Tumori Giovanni Paolo II, 70124 Bari, Italy; (L.P.); (A.A.)
| | - Gabriella Guida
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari-“Aldo Moro”, 70125 Bari, Italy; (M.M.); (A.F.)
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12
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Herraiz C, Martínez-Vicente I, Maresca V. The α-melanocyte-stimulating hormone/melanocortin-1 receptor interaction: A driver of pleiotropic effects beyond pigmentation. Pigment Cell Melanoma Res 2021; 34:748-761. [PMID: 33884776 DOI: 10.1111/pcmr.12980] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/25/2021] [Accepted: 04/13/2021] [Indexed: 12/21/2022]
Abstract
Melanocortin-1 Receptor (MC1R), when stimulated by alpha-melanocyte-stimulating hormone (α-MSH), is a driver of eumelanogenesis. Brown/black eumelanin is an effective filter against ultraviolet radiation (UVR) and is a scavenger of free radicals. Several polymorphic variants of MC1R are frequent in red-head people. These polymorphisms reduce the ability of MC1R to promote eumelanogenesis after its activation and spontaneous pheomelanogenesis take place. Since pheomelanin can act as an endogenous photosensitizer, people carrying MC1R polymorphisms are more susceptible to skin cancer. Here, we summarize current knowledge on the biology of MC1R beyond its ability to drive eumelanogenesis. We analyze its capacity to cope with oxidative insult and consequent DNA damage. We describe its ability to transduce through different pathways. We start from the canonical pathway, the cAMP/protein kinase A (PKA) pathway mainly involved in promoting eumelanogenesis, and protection from oxidative damage, and we then move on to describe more recent knowledge concerning ERK pathways, phosphoinositide 3-kinase (PI3K) pathway/AKT, and α-MSH/Peroxisome proliferators activated receptor-γ (PPAR-γ) connection. We describe MC1R polymorphic variants associated with melanoma risk which represent an open window of clinical relevance.
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Affiliation(s)
- Cecilia Herraiz
- Department of Biochemistry, Molecular Biology and Immunology, School of Medicine, University of Murcia and Instituto Murciano de Investigación Biosanitaria (IMIB), Murcia, Spain
| | - Idoya Martínez-Vicente
- Department of Biochemistry, Molecular Biology and Immunology, School of Medicine, University of Murcia and Instituto Murciano de Investigación Biosanitaria (IMIB), Murcia, Spain
| | - Vittoria Maresca
- Laboratory of Cutaneous Physiopathology, San Gallicano Dermatological Institute IRCCS, Rome, Italy
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Lim D, Lee KJ, Kim Y, Kim M, Ju HM, Kim MJ, Choi DH, Choi J, Kim S, Kang D, Lee K, Hahn JH. A Basic Domain-Derived Tripeptide Inhibits MITF Activity by Reducing its Binding to the Promoter of Target Genes. J Invest Dermatol 2021; 141:2459-2469. [PMID: 33823181 DOI: 10.1016/j.jid.2021.01.037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 12/23/2020] [Accepted: 01/20/2021] [Indexed: 12/28/2022]
Abstract
The keratinocytes in UV-irradiated skin produce and secrete α-melanocyte-stimulating hormone. α-Melanocyte-stimulating hormone upregulates the expression of MITF in melanocytes through the cAMP‒protein kinase A‒CREB signaling pathway. Thereafter, MITF induces the expression of melanogenic genes, including the tyrosinase gene TYR and TYRP-1 and TYRP-2 genes, which leads to the synthesis and accumulation of melanin. In this study, we examined whether MITF basic region-derived tripeptides can bind to the DNA-binding domain of MITF and inhibit MITF-induced melanogenesis through the inhibition of MITF‒DNA binding. MITF-KGR, a representative MITF-derived tripeptide, suppressed the transcriptional activity of MITF by disrupting its binding to the promoter region of the target genes, which resulted in the inhibition of skin epidermis thickness and melanin synthesis in vivo and in vitro. Our results indicate that MITF-KGR exerts an inhibitory effect on melanogenesis by targeting MITF.
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Affiliation(s)
- Dongyoung Lim
- Department of Anatomy and Cell Biology, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea
| | - Kyoung-Jin Lee
- Department of Anatomy and Cell Biology, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea
| | - Yuri Kim
- Department of Anatomy and Cell Biology, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea
| | - Minseo Kim
- Department of Anatomy and Cell Biology, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea
| | - Hyun-Mi Ju
- Department of Anatomy and Cell Biology, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea
| | - Myoung-Ju Kim
- Department of Anatomy and Cell Biology, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea
| | - Dong-Hwa Choi
- Biocenter, Gyeonggido Business & Science Accelerator, Suwon, Republic of Korea
| | - Jiwon Choi
- Department of Oral Pathology, Oral Cancer Research Institute, College of Dentistry, Yonsei University, Seoul, Republic of Korea
| | - Suree Kim
- Department of Life Science, Ewha Womans University, Seoul, Republic of Korea; Western Seoul Center, Korea Basic Science Institute, Seoul, Republic of Korea
| | - Dongmin Kang
- Department of Life Science, Ewha Womans University, Seoul, Republic of Korea
| | - Kyoungyul Lee
- Department of Pathology, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea
| | - Jang-Hee Hahn
- Department of Anatomy and Cell Biology, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea.
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14
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Thompson MJW, Jones G, Balogun SA, Aitken DA. Skin Photosensitivity is Associated with 25-Hydroxyvitamin D and BMD but not Fractures Independent of Melanin Density in Older Caucasian Adults. Calcif Tissue Int 2020; 107:335-344. [PMID: 32696106 DOI: 10.1007/s00223-020-00728-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Accepted: 07/10/2020] [Indexed: 11/24/2022]
Abstract
Whether skin photosensitivity modulates sun exposure behaviours, consequent vitamin D status and skeletal health outcomes independently of constitutive pigmentation have not been systematically investigated. 1072 community-dwelling adults aged 50-80 years had skin photosensitivity quantified by questionnaire and melanin density by spectrophotometry. Bone mineral density (BMD), falls risk and 25-hydroxyvitamin D (25OHD) were measured using DXA, short form physiological profile assessment and radioimmunoassay, respectively. Sun exposure and symptomatic fractures were assessed by questionnaire. Participants were followed up at 2.5 (n = 879), 5 (n = 767) and 10 (n = 571) years. Higher resistance to sunburn and greater ability to tan were associated with reduced sun protection behaviours (RR 0.87, p < 0.001 & RR 0.88, p < 0.001), higher lifetime discretionary sun exposure in summer (RR 1.05, p = 0.001 & RR 1.07, p = 0.001) and winter (RR 1.07, p = 0.001 & RR 1.08, p = 0.02) and fewer lifetime sunburns (RR 0.86, p < 0.001 & RR 0.91, p = 0.001). Higher resistance to sunburn was associated with lower total body (β = - 0.006, p = 0.047) and femoral neck (β = - 0.006, p = 0.038) BMD, but paradoxically, fewer prevalent fractures (RR 0.94, p = 0.042). Greater ability to tan was associated with higher 25OHD (β = 1.43, p = 0.04), lumbar spine (β = 0.014, p = 0.046) and total body (β = 0.013, p = 0.006) BMD, but not fracture or falls risk. These associations were independent of constitutive melanin density. Cutaneous photosensitivity was associated with sun exposure behaviours, cutaneous sequelae and, consequently, 25OHD and BMD in older Caucasian adults independent of constitutive melanin density. There was no consistent association with fracture outcomes, suggesting environmental factors are at least as important.
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Affiliation(s)
- M J W Thompson
- Menzies Institute for Medical Research, University of Tasmania, 17 Liverpool St, Hobart, TAS, 7000, Australia.
| | - G Jones
- Menzies Institute for Medical Research, University of Tasmania, 17 Liverpool St, Hobart, TAS, 7000, Australia
| | - S A Balogun
- Menzies Institute for Medical Research, University of Tasmania, 17 Liverpool St, Hobart, TAS, 7000, Australia
| | - D A Aitken
- Menzies Institute for Medical Research, University of Tasmania, 17 Liverpool St, Hobart, TAS, 7000, Australia
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15
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Mosca S, Cardinali G, Flori E, Briganti S, Bottillo I, Mileo AM, Maresca V. The PI3K pathway induced by αMSH exerts a negative feedback on melanogenesis and contributes to the release of pigment. Pigment Cell Melanoma Res 2020; 34:72-88. [PMID: 32608114 DOI: 10.1111/pcmr.12910] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 06/15/2020] [Accepted: 06/22/2020] [Indexed: 02/06/2023]
Abstract
The melanocortin-1 receptor (MC1R) belongs to the family of the G protein-coupled receptor (GPCR). Activated GPCRs can promote the phosphoinositide 3-kinase (PI3K) pathway. Few studies deal with the role of the PI3K pathway activation in response to αMSH. On B16-F10 cell line, we investigated the αMSH-dependent modulation of pAKT/AKT, as a key element of the PI3K pathway after rapid and prolonged stimulation. We demonstrated that αMSH triggers a rapid modulation of AKT which culminates in an increase in its phosphorylation. We highlighted a comparable upregulation of pAKT after exposure to αMSH on primary cultures of normal human melanocytes (NHMs) expressing a wild-type MC1R. On B16-F10 cells, NHMs, and an ex vivo model of human skin biopsies, we explored the influence of PI3K/AKT signaling triggered by αMSH, focusing on the control of melanogenesis and pigment release. We showed that the αMSH-dependent PI3K/AKT pathway exerts a negative feedback on melanogenesis and promotes the extracellular release of pigment. We strengthened the role of the PI3K/AKT pathway triggered by αMSH in preserving redox equilibrium and genome integrity, highlighting its role in affecting cell survival.
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Affiliation(s)
- Sarah Mosca
- Laboratory of Cutaneous Physiopathology, San Gallicano Dermatological Institute IRCCS, Rome, Italy
| | - Giorgia Cardinali
- Laboratory of Cutaneous Physiopathology, San Gallicano Dermatological Institute IRCCS, Rome, Italy
| | - Enrica Flori
- Laboratory of Cutaneous Physiopathology, San Gallicano Dermatological Institute IRCCS, Rome, Italy
| | - Stefania Briganti
- Laboratory of Cutaneous Physiopathology, San Gallicano Dermatological Institute IRCCS, Rome, Italy
| | - Irene Bottillo
- Laboratory of Medical Genetics, Department of Molecular Medicine, San Camillo Forlanini Hospital, Sapienza University of Rome, Rome, Italy
| | - Anna M Mileo
- Department of Research Advanced Diagnostic and Technological Innovation - Tumor Immunology and Immunotherapy Unit, IRCCS-Regina Elena National Cancer Institute, Rome, Italy
| | - Vittoria Maresca
- Laboratory of Cutaneous Physiopathology, San Gallicano Dermatological Institute IRCCS, Rome, Italy
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Song H, Hwang YJ, Ha JW, Boo YC. Screening of an Epigenetic Drug Library Identifies 4-((hydroxyamino)carbonyl)- N-(2-hydroxyethyl)- N-Phenyl-Benzeneacetamide that Reduces Melanin Synthesis by Inhibiting Tyrosinase Activity Independently of Epigenetic Mechanisms. Int J Mol Sci 2020; 21:ijms21134589. [PMID: 32605171 PMCID: PMC7370187 DOI: 10.3390/ijms21134589] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 06/17/2020] [Accepted: 06/27/2020] [Indexed: 12/16/2022] Open
Abstract
The aim of this study was to identify novel antimelanogenic drugs from an epigenetic screening library containing various modulators targeting DNA methyltransferases, histone deacetylases, and other related enzymes/proteins. Of 141 drugs tested, K8 (4-((hydroxyamino)carbonyl)-N-(2-hydroxyethyl)-N-phenyl-benzeneacetamide; HPOB) was found to effectively inhibit the α-melanocyte-stimulating hormone (α-MSH)-induced melanin synthesis in B16-F10 murine melanoma cells without accompanying cytotoxicity. Additional experiments showed that K8 did not significantly reduce the mRNA and protein level of tyrosinase (TYR) or microphthalmia-associated transcription factor (MITF) in cells, but it potently inhibited the catalytic activity TYR in vitro (IC50, 1.1-1.5 µM) as compared to β-arbutin (IC50, 500-700 µM) or kojic acid (IC50, 63 µM). K8 showed copper chelating activity similar to kojic acid. Therefore, these data suggest that K8 inhibits cellular melanin synthesis not by downregulation of TYR protein expression through an epigenetic mechanism, but by direct inhibition of TYR catalytic activity through copper chelation. Metal chelating activity of K8 is not surprising because it is known to inhibit histone deacetylase (HDAC) 6 through zinc chelation. This study identified K8 as a potent inhibitor of cellular melanin synthesis, which may be useful for the treatment of hyperpigmentation disorders.
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Affiliation(s)
- Hyerim Song
- Department of Molecular Medicine, School of Medicine, Kyungpook National University, Daegu 41944, Korea; (H.S.); (Y.J.H.); (J.W.H.)
- Brain Korea (BK) 21 Plus Kyungpook National University (KNU) Biomedical Convergence Program, Kyungpook National University, Daegu 41944, Korea
| | - Yun Jeong Hwang
- Department of Molecular Medicine, School of Medicine, Kyungpook National University, Daegu 41944, Korea; (H.S.); (Y.J.H.); (J.W.H.)
- Brain Korea (BK) 21 Plus Kyungpook National University (KNU) Biomedical Convergence Program, Kyungpook National University, Daegu 41944, Korea
| | - Jae Won Ha
- Department of Molecular Medicine, School of Medicine, Kyungpook National University, Daegu 41944, Korea; (H.S.); (Y.J.H.); (J.W.H.)
- Brain Korea (BK) 21 Plus Kyungpook National University (KNU) Biomedical Convergence Program, Kyungpook National University, Daegu 41944, Korea
| | - Yong Chool Boo
- Department of Molecular Medicine, School of Medicine, Kyungpook National University, Daegu 41944, Korea; (H.S.); (Y.J.H.); (J.W.H.)
- Brain Korea (BK) 21 Plus Kyungpook National University (KNU) Biomedical Convergence Program, Kyungpook National University, Daegu 41944, Korea
- Cell and Matrix Research Institute, Kyungpook National University, Daegu 41944, Korea
- Correspondence: ; Tel.: +82-53-420-4946
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17
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Khafagy GM, Nada HR, Rashid LA, El-Samanoudy SI, Abd El-Sattar EM. Role of trace elements in pityriasis Alba. J Trace Elem Med Biol 2020; 59:126422. [PMID: 31708253 DOI: 10.1016/j.jtemb.2019.126422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 10/13/2019] [Accepted: 10/22/2019] [Indexed: 01/19/2023]
Abstract
BACKGROUND Pityriasis Alba (PA) is a common skin disorder affecting the children and it has multiple risk factors. OBJECTIVES To assess the serum levels of trace elements (copper, zinc, and magnesium) and hemoglobin (Hb) level in patients with PA. METHOD This is a case control study; 110 participants (55 cases and 55 controls) were recruited from pediatric dermatology and family medicine clinics, Cairo university hospitals. Patients were allocated into two groups, PA group (randomly selected male and female children age group (6-16) with PA lesions) and a matched control group. Full history was taken including sociodemographic data, present history of the lesions. Full general and dermatological examination was done. Blood samples were taken to asses iron and trace elements levels. The gained measures were analyzed by (SPSS) program version 22. RESULTS This study showed that Hb levels, serum ferritin, copper, zinc and magnesium were significantly lower in PA group. There was statistically significant difference between both cases and controls regarding trace elements (copper, zinc, and magnesium) with (p value was 0.000, 0.000 and 0.003) respectively. Zinc deficiency increased the risk by more than 15 folds. Also, there was statistically significant difference between both groups regarding Hb levels and serum ferritin (p value was 0.000). The reduced Hb level increases the risk of PA by more than nine folds (OR 9.6) CONCLUSION: PA is associated with reduced levels of Hb, serum zinc, ferritin, copper and magnesium; sun exposure, skin phototype were found to be important risk factors for PA.
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Affiliation(s)
- Ghada M Khafagy
- Department of Family Medicine, Faculty of Medicine, Cairo University, Egypt.
| | - Hanan R Nada
- Department of Dermatology, Faculty of Medicine, Cairo University, Egypt
| | - Laila A Rashid
- Department of Clinical biochemistry and molecular biology, Faculty of Medicine, Cairo University, Egypt
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18
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Boo YC. p-Coumaric Acid as An Active Ingredient in Cosmetics: A Review Focusing on its Antimelanogenic Effects. Antioxidants (Basel) 2019; 8:E275. [PMID: 31382682 PMCID: PMC6720745 DOI: 10.3390/antiox8080275] [Citation(s) in RCA: 113] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 08/01/2019] [Accepted: 08/02/2019] [Indexed: 12/16/2022] Open
Abstract
Controlling unwanted hyperpigmentation is a major challenge in dermatology and cosmetology, and safe and efficacious antimelanogenic agents are deemed useful for this purpose. p-Coumaric acid is a natural metabolite contained in many edible plants, and its antioxidant activities in reducing oxidative stress and inflammatory reactions have been demonstrated in various experimental models. p-Coumaric acid has the optimal structure to be a competitive inhibitor of tyrosinase that catalyzes key reactions in the melanin biosynthetic pathway. Experimental evidence supports this notion as it was found to be a more potent inhibitor of tyrosinase, especially toward human enzymes, than other well-known tyrosinase inhibitors such as arbutin and kojic acid. p-Coumaric acid inhibited melanin synthesis in murine melanoma cells, human epidermal melanocytes, and reconstituted three-dimensional human skin models. Ex-vivo skin permeation experiments and in-vivo efficacy tests for p-coumaric acid confirmed its efficient transdermal delivery and functional efficacy in reducing erythema development and skin pigmentation due to ultraviolet radiation exposure. Human studies further supported its effectiveness in hypopigmentation and depigmentation. These findings suggest that p-coumaric acid has good potential to be used as a skin-lightening active ingredient in cosmetics. Future studies are needed to extensively examine its safety and efficacy and to develop an optimized cosmetic formulation for the best performance in skin lightening.
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Affiliation(s)
- Yong Chool Boo
- Department of Molecular Medicine, School of Medicine, Kyungpook National University, Daegu 41944, Korea.
- BK21 Plus KNU Biomedical Convergence Program, Kyungpook National University, Daegu 41944, Korea.
- Cell and Matrix Research Institute, Kyungpook National University, Daegu 41944, Korea.
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Abstract
Skin phototyping refers to a skin classification scheme based on how the skin responds to sun exposure. The Fitzpatrick classification is the most widely accepted method of skin phototyping, based on a person's tendency to sunburn and ability to tan. Apart from estimating the initial therapeutic dose of UV light, skin phototyping is also useful in predicting the risk of photodamage and skin cancer and the outcome of esthetic procedures. Techniques to type the skin objectively have been developed to address the deficiencies associated with the subjective Fitzpatrick classification. Some skin typing systems have been proposed specifically to predict the response of skin to cosmetic procedures such as chemical peeling and laser resurfacing. We discuss the concept of skin type and its relation to skin color, as well as critically appraising the various available methods of skin typing.
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Affiliation(s)
- Vishal Gupta
- Department of Dermatology and Venereology, All India Institute of Medical Sciences, New Delhi, India
| | - Vinod Kumar Sharma
- Department of Dermatology and Venereology, All India Institute of Medical Sciences, New Delhi, India.
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20
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Tam I, Dzierżęga-Lęcznar A, Stępień K. Differential expression of inflammatory cytokines and chemokines in lipopolysaccharide-stimulated melanocytes from lightly and darkly pigmented skin. Exp Dermatol 2019; 28:551-560. [PMID: 30801846 DOI: 10.1111/exd.13908] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 02/11/2019] [Indexed: 01/02/2023]
Abstract
Increasing evidence suggests that human epidermal melanocytes play an important role in the skin immune system; however, a role of their pigmentation in immune and inflammatory responses is poorly examined. In the study, the expression of Toll-like receptor 4 (TLR4) and inflammatory cytokines and chemokines by cultured normal melanocytes derived from lightly and darkly pigmented skin was investigated after cell stimulation with lipopolysaccharide (LPS). The basal TLR4 mRNA level in heavily pigmented cells was higher as compared to their lightly pigmented counterparts. Melanocyte exposure to LPS upregulated the expression of TLR4 mRNA and enhanced the DNA-binding activity of NF-κB p50 and p65. We found substantial differences in the LPS-stimulated expression of numerous genes encoding inflammatory cytokines and chemokines between the cells with various melanin contents. In lightly pigmented melanocytes, the most significantly upregulated genes were nicotinamide phosphoribosyltransferase (NAMPT/visfatin), the chemokines CCL2 and CCL20, and IL6, while the genes for CXCL12, IL-16 and the chemokine receptor CCR4 were the most significantly upregulated in heavily pigmented cells. Moreover, the lightly pigmented melanocytes secreted much more NAMPT, CCL2 and IL-6. The results of our study suggest modulatory effect of melanogenesis on the immune properties of normal epidermal melanocytes.
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Affiliation(s)
- Irena Tam
- Department of Instrumental Analysis, School of Pharmacy with the Division of Laboratory Medicine, Medical University of Silesia in Katowice, Sosnowiec, Poland
| | - Anna Dzierżęga-Lęcznar
- Department of Instrumental Analysis, School of Pharmacy with the Division of Laboratory Medicine, Medical University of Silesia in Katowice, Sosnowiec, Poland
| | - Krystyna Stępień
- Department of Instrumental Analysis, School of Pharmacy with the Division of Laboratory Medicine, Medical University of Silesia in Katowice, Sosnowiec, Poland
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21
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Matthews NH, Fitch K, Li WQ, Morris JS, Christiani DC, Qureshi AA, Cho E. Exposure to Trace Elements and Risk of Skin Cancer: A Systematic Review of Epidemiologic Studies. Cancer Epidemiol Biomarkers Prev 2019; 28:3-21. [PMID: 30297516 PMCID: PMC6324965 DOI: 10.1158/1055-9965.epi-18-0286] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 07/30/2018] [Accepted: 09/28/2018] [Indexed: 12/11/2022] Open
Abstract
Exposure to environmental trace elements has been studied in relation to many cancers. However, an association between exposure to trace elements and skin cancer remains less understood. Therefore, we conducted a systematic review of published epidemiologic literature examining the association between exposure to trace elements, and risk of melanoma and keratinocyte carcinoma in humans. We identified epidemiologic studies investigating exposure to arsenic, cadmium, chromium, copper, iron, selenium, and zinc and risk of skin cancer in humans. Among the minerals, arsenic, selenium, and zinc had more than five studies available. Exposure to arsenic was associated with increased risk of keratinocyte carcinoma, while too few studies existed on melanoma to draw conclusions. Exposure to selenium was associated with possible increased risk of keratinocyte carcinoma. Studies of zinc and skin cancer were case-control in design and were found to have inconsistent associations. The data on the association between cadmium, chromium, copper, and iron and risk of skin cancer remain too sparse to draw any conclusions. In summary, epidemiologic studies on exposure to trace elements and cutaneous malignancies are limited. Studies with larger sample sizes and prospective designs are warranted to improve our knowledge of trace elements and skin cancer.
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Affiliation(s)
- Natalie H Matthews
- Department of Dermatology, The Warren Alpert Medical School, Brown University, Providence, Rhode Island
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Katherine Fitch
- Department of Dermatology, The Warren Alpert Medical School, Brown University, Providence, Rhode Island
| | - Wen-Qing Li
- Department of Dermatology, The Warren Alpert Medical School, Brown University, Providence, Rhode Island
- Department of Epidemiology, Brown University School of Public Health, Providence, Rhode Island
| | - J Steven Morris
- Research Reactor Center, University of Missouri-Columbia and Harry S. Truman Memorial Veterans Hospital, Columbia, Missouri
| | - David C Christiani
- Department of Environmental Health, Harvard T. H. Chan School of Public Health, Boston, Massachusetts
- Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, Massachusetts
- Pulmonary and Critical Care Unit, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts
| | - Abrar A Qureshi
- Department of Dermatology, The Warren Alpert Medical School, Brown University, Providence, Rhode Island
- Department of Epidemiology, Brown University School of Public Health, Providence, Rhode Island
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
- Department of Dermatology, Rhode Island Hospital, Providence, Rhode Island
| | - Eunyoung Cho
- Department of Dermatology, The Warren Alpert Medical School, Brown University, Providence, Rhode Island.
- Department of Epidemiology, Brown University School of Public Health, Providence, Rhode Island
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
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22
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Slape D, Tang J, Lawless R, McCrossin I, Frew JW. A retrospective cohort study of melanoma prevalence stratified by body site in a Regional Australian Population 1994-2017: Site-specific protective mechanisms. PHOTODERMATOLOGY PHOTOIMMUNOLOGY & PHOTOMEDICINE 2018; 35:135-140. [PMID: 30381854 DOI: 10.1111/phpp.12436] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 10/18/2018] [Accepted: 10/29/2018] [Indexed: 01/19/2023]
Abstract
BACKGROUND Australia has the highest incidence of cutaneous melanoma worldwide. Previous studies have identified some body areas (forearms and dorsal hands) have lower rates of melanoma than expected when compared with other similarly exposed areas, leading to the suggestion that endogenous immunological protective mechanisms in certain body sites may exist. AIMS AND METHODS We hypothesise that examination of melanoma by body site in a regional Australian setting would demonstrate no significant variation in the incidence of melanoma across highly sun exposed areas including the head and neck and upper limbs. Results were stratified by body site and further examined by univariate correlation analysis by gender, age, body site, Breslow thickness and subtype. Polytomous logistic regression was used to test the difference in risk factors by location of melanoma. RESULTS A total of 772 melanomas were included in the analysis. Melanomas of the upper limb were more likely to affect females (OR = 2.415 95%CI: 1.433-4.072) and more likely to be thinner than other body sites. Compared to other international studies, statistically significant decreased rates of melanoma were seen on the upper limb compared to other areas of the body (X2 = 16.29, P < 0.001). Examination of sites of melanoma on the upper limb showed significantly decreased rate on the distal upper limb given relative body surface areas (X2 = 6.30 P = 0.04). DISCUSSION AND CONCLUSIONS Our study was limited by its retrospective nature, and the findings require validation in a larger prospective cohort. Further exploration of such mechanisms may lead to new insights into the immunological mechanisms surrounding cutaneous melanoma.
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Affiliation(s)
- Dana Slape
- Liverpool Hospital, Department of Dermatology, Liverpool, New South Wales, Australia
| | - Johnson Tang
- University of New South Wales, Randwick, New South Wales, Australia
| | - Ruth Lawless
- Liverpool Hospital, Department of Dermatology, Liverpool, New South Wales, Australia
| | - Ian McCrossin
- Liverpool Hospital, Department of Dermatology, Liverpool, New South Wales, Australia.,University of New South Wales, Randwick, New South Wales, Australia
| | - John W Frew
- Liverpool Hospital, Department of Dermatology, Liverpool, New South Wales, Australia.,University of New South Wales, Randwick, New South Wales, Australia.,Ingham Institute of Applied Medical Research, University of New South Wales, Randwick, New South Wales, Australia
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23
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Affiliation(s)
- Mauro Picardo
- Cutaneous Physiopathology Laboratory and Metabolomic Center, San Gallicano Dermatological Institute, Rome, Italy
| | - Andrzej T Slominski
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL, USA.,Comprehensive Cancer Center Cancer Chemoprevention Program, University of Alabama at Birmingham, Birmingham, AL, USA.,Laboratory Service of the VA Medical Center, Birmingham, AL, USA
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Kim KI, Jo JW, Lee JH, Kim CD, Yoon TJ. Induction of pigmentation by a small molecule tyrosine kinase inhibitor nilotinib. Biochem Biophys Res Commun 2018; 503:2271-2276. [PMID: 29959921 DOI: 10.1016/j.bbrc.2018.06.148] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 06/27/2018] [Indexed: 12/12/2022]
Abstract
Skin color is determined by the melanin pigments that are produced in melanocytes then transferred to surrounding keratinocytes. Despite the growing number of commercial products claiming the pigmentation-regulatory effects, there is still a demand for the development of new materials that are safe and more efficacious. We tried to screen the pigmentation-regulatory materials using a commercially available drugs, and found that nilotinib could induce pigmentation in melanoma cells. When HM3KO melanoma cells were treated with nilotinib, melanin content was increased together with increase of tyrosinase activity. Nilotinib increased the expression of pigmentation-related genes such as MITF, tyrosinase and TRP1. Consistent with these results, the protein level for MITF, tyrosinase, and TRP1 was significantly increased by nilotinib. To delineate the action mechanism of nilotinib, we investigated the effects of nilotinib on intracellular signaling. As a result, nilotinib decreased the phosphorylation of AKT, while increased the phosphorylation of CREB. The pretreatment of PKA inhibitor H89 markedly blocked the nilotinib-induced phosphorylation of CREB. In accordance with, pretreatment of H89 significantly inhibited the nilotinib-induced pigmentation, indicating that nilotinib induces pigmentation via the activation of PKA signaling. Together, our data suggest that nilotinib can be developed for the treatment of hypopigmentary disorder such as vitiligo.
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Affiliation(s)
- Kyung-Il Kim
- Department of Medical Science, School of Medicine, Chungnam National University, Daejeon, South Korea; Department of Dermatology and Institute of Health Sciences, School of Medicine, Gyeongsang National University & Hospital, Jinju, South Korea
| | - Jeong Won Jo
- Department of Dermatology and Institute of Health Sciences, School of Medicine, Gyeongsang National University & Hospital, Jinju, South Korea
| | - Jeung-Hoon Lee
- Department of Medical Science, School of Medicine, Chungnam National University, Daejeon, South Korea; Department of Dermatology, School of Medicine, Chungnam National University, Daejeon, South Korea; Skin Med Co., Daejeon, South Korea
| | - Chang Deok Kim
- Department of Medical Science, School of Medicine, Chungnam National University, Daejeon, South Korea; Department of Dermatology, School of Medicine, Chungnam National University, Daejeon, South Korea.
| | - Tae-Jin Yoon
- Department of Dermatology and Institute of Health Sciences, School of Medicine, Gyeongsang National University & Hospital, Jinju, South Korea.
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25
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Passeron T, Picardo M. Melasma, a photoaging disorder. Pigment Cell Melanoma Res 2018; 31:461-465. [PMID: 29285880 DOI: 10.1111/pcmr.12684] [Citation(s) in RCA: 111] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 12/05/2017] [Indexed: 12/17/2022]
Abstract
Melasma is a common hyperpigmentary disorder. The impact on the quality of life of affected individuals is well demonstrated, demanding new therapeutic strategies. However, the treatment of melasma remains highly challenging. Melasma is often considered as the main consequence of female hormone stimulation on a predisposed genetic background. Although these two factors do contribute to this acquired pigmentary disorder, the last decade has revealed several other key players and brought new pieces to the complex puzzle of the pathophysiology of melasma. Here, we summarize the latest evidence on the pathophysiology of melasma, and we suggest that melasma might be a photoaging skin disorder affecting genetically predisposed individuals. Such data must be taken into consideration by clinicians as they could have a profound impact on the treatment and the prevention of melasma.
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Affiliation(s)
- Thierry Passeron
- Department of Dermatology, Université Côte D'Azur, Centre Hospitalier Universitaire Nice, Nice, France.,INSERM, Université Côte d'Azur, U1065, C3M, Nice, France
| | - Mauro Picardo
- San Gallicano Dermatologic Institute, IRCCS, Rome, Italy
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26
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Thomas NE, Edmiston SN, Kanetsky PA, Busam KJ, Kricker A, Armstrong BK, Cust AE, Anton-Culver H, Gruber SB, Luo L, Orlow I, Reiner AS, Gallagher RP, Zanetti R, Rosso S, Sacchetto L, Dwyer T, Parrish EA, Hao H, Gibbs DC, Frank JS, Ollila DW, Begg CB, Berwick M, Conway K. Associations of MC1R Genotype and Patient Phenotypes with BRAF and NRAS Mutations in Melanoma. J Invest Dermatol 2017; 137:2588-2598. [PMID: 28842324 PMCID: PMC5701875 DOI: 10.1016/j.jid.2017.07.832] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2017] [Revised: 07/08/2017] [Accepted: 07/23/2017] [Indexed: 11/21/2022]
Abstract
Associations of MC1R with BRAF mutations in melanoma have been inconsistent between studies. We sought to determine for 1,227 participants in the international population-based Genes, Environment, and Melanoma (GEM) study whether MC1R and phenotypes were associated with melanoma BRAF/NRAS subtypes. We used logistic regression adjusted by age, sex, and study design features and examined effect modifications. BRAF+ were associated with younger age, blond/light brown hair, increased nevi, and less freckling, and NRAS+ with older age relative to the wild type (BRAF-/NRAS-) melanomas (all P < 0.05). Comparing specific BRAF subtypes to the wild type, BRAF V600E was associated with younger age, blond/light brown hair, and increased nevi and V600K with increased nevi and less freckling (all P < 0.05). MC1R was positively associated with BRAF V600E cases but only among individuals with darker phototypes or darker hair (Pinteraction < 0.05) but inversely associated with BRAF V600K (Ptrend = 0.006) with no significant effect modification by phenotypes. These results support distinct etiologies for BRAF V600E, BRAF V600K, NRAS+, and wild-type melanomas. MC1R's associations with BRAF V600E cases limited to individuals with darker phenotypes indicate that MC1R genotypes specifically provide information about BRAF V600E melanoma risk in those not considered high risk based on phenotype. Our results also suggest that melanin pathways deserve further study in BRAF V600E melanomagenesis.
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Affiliation(s)
- Nancy E Thomas
- Department of Dermatology, University of North Carolina, Chapel Hill, North Carolina, USA; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina, USA.
| | - Sharon N Edmiston
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Peter A Kanetsky
- Department of Cancer Epidemiology, Moffitt Cancer Center, Tampa, Florida, USA
| | - Klaus J Busam
- Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, USA
| | - Anne Kricker
- Sydney School of Public Health, University of Sydney, Sydney, New South Wales, Australia
| | - Bruce K Armstrong
- Sydney School of Public Health, University of Sydney, Sydney, New South Wales, Australia
| | - Anne E Cust
- Sydney School of Public Health, University of Sydney, Sydney, New South Wales, Australia; Melanoma Institute Australia, North Sydney, Australia
| | - Hoda Anton-Culver
- Department of Epidemiology, University of California, Irvine, California, USA
| | - Stephen B Gruber
- Univeristy of Southern California Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, USA
| | - Li Luo
- Department of Internal Medicine, University of New Mexico Cancer Center, University of New Mexico, Albuquerque, New Mexico, USA
| | - Irene Orlow
- Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, USA
| | - Anne S Reiner
- Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, USA
| | | | - Roberto Zanetti
- Piedmont Cancer Registry, Centre for Epidemiology and Prevention in Oncology in Piedmont, Turin, Italy
| | - Stefano Rosso
- Piedmont Cancer Registry, Centre for Epidemiology and Prevention in Oncology in Piedmont, Turin, Italy
| | - Lidia Sacchetto
- Department of Dermatology, University of North Carolina, Chapel Hill, North Carolina, USA; Politecnico di Torino, Turin, Italy
| | - Terence Dwyer
- George Institute for Global Health, Nuffield Department of Obstetrics and Gynecology, University of Oxford
| | - Eloise A Parrish
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Honglin Hao
- Department of Dermatology, University of North Carolina, Chapel Hill, North Carolina, USA
| | - David C Gibbs
- Department of Dermatology, University of North Carolina, Chapel Hill, North Carolina, USA; Department of Epidemiology, Emory University, Atlanta, Georgia, USA
| | - Jill S Frank
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina, USA
| | - David W Ollila
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina, USA; Department of Surgery, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Colin B Begg
- Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, USA
| | - Marianne Berwick
- Department of Internal Medicine, University of New Mexico Cancer Center, University of New Mexico, Albuquerque, New Mexico, USA
| | - Kathleen Conway
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina, USA; Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina, USA
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Zhu Y, Pan WH, Ku CF, Zhang HJ, Tsang SW. Design, synthesis and evaluation of novel dihydrostilbene derivatives as potential anti-melanogenic skin-protecting agents. Eur J Med Chem 2017; 143:1254-1260. [PMID: 29150333 DOI: 10.1016/j.ejmech.2017.10.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 09/20/2017] [Accepted: 10/08/2017] [Indexed: 10/18/2022]
Abstract
The stems of Dendrobium orchids (Orchidaceae), also known as Shi Hu, have been used for medicinal purposes for centuries in oriental countries. In fact, the health benefits of Shi Hu have been evidenced by its modern pharmacological actions on conquering oxidative stress in pathological conditions. From the extracts of two commonly used Dendrobium species, we obtained discernible amounts of stilbenoids, explicitly trans-resveratrol (1) and dihydro-resveratrol (2), which are prototypical antioxidants. When applied to cultured melanocytes, these stilbenoids, dihydro-resveratrol (2) in particular, significantly reduced melanin formation via inhibiting tyrosinase activity and expression of tyrosinase-related proteins. By utilizing dihydro-resveratrol (2) as the basic structural unit, we synthesized 11 novel dihydrostilbene derivatives (3-13) in good yields and purity, with manipulative steps. In addition to their anti-melanogenic activity, some of the novel derivatives are indeed potential antioxidants as they quenched intracellular oxidative radicals in a manner more efficient than Trolox, a water-soluble analogue of vitamin E, and thus premeditated beneficial to skin protection.
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Affiliation(s)
- Yu Zhu
- Teaching and Research Division, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China
| | - Wen-Hui Pan
- Teaching and Research Division, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China
| | - Chuen Fai Ku
- Teaching and Research Division, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China
| | - Hong-Jie Zhang
- Teaching and Research Division, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China; Institute of Research and Continuing Education, Hong Kong Baptist University Shenzhen Research Centre, Shenzhen, China.
| | - Siu Wai Tsang
- Teaching and Research Division, School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China; Institute of Research and Continuing Education, Hong Kong Baptist University Shenzhen Research Centre, Shenzhen, China.
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28
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Flori E, Mastrofrancesco A, Kovacs D, Bellei B, Briganti S, Maresca V, Cardinali G, Picardo M. The activation of PPARγ by 2,4,6-Octatrienoic acid protects human keratinocytes from UVR-induced damages. Sci Rep 2017; 7:9241. [PMID: 28835664 PMCID: PMC5569026 DOI: 10.1038/s41598-017-09578-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 07/21/2017] [Indexed: 02/08/2023] Open
Abstract
Increasing attention is addressed to identify products able to enhance skin photoprotection and to prevent skin carcinogenesis. Several studies have demonstrated that the α-melanocyte stimulating hormone (αMSH), acting on a functional MC1R, provides a photoprotective effect by inducing pigmentation, antioxidants and DNA repair. We discovered a link between αMSH and the nuclear receptor Peroxisome Proliferator-Activated Receptor-γ (PPARγ), suggesting that some of the αMSH protective effects may be dependent on PPARγ transcriptional activity. Moreover, we demonstrated that the activation of PPARγ by the parrodiene 2,4,6-octatrienoic acid (Octa) induces melanogenesis and antioxidant defence in human melanocytes and counteracts senescence-like phenotype in human fibroblasts. In this study, we demonstrate that the activation of PPARγ by Octa exerts a protective effect against UVA- and UVB-induced damage on normal human keratinocytes (NHKs), the major target cells of UV radiation. Octa promotes the antioxidant defence, augments DNA repair and reduces the induction of proteins involved in UV-induced DNA damage response. Our results contribute to deepen the analysis of the αMSH/PPARγ connection and suggest perspectives for the development of new molecules and formulations able to prevent cutaneous UV damage by acting on the different skin cell populations through PPARγ activation.
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Affiliation(s)
- Enrica Flori
- Laboratory of Cutaneous Physiopathology and Integrated Center of Metabolomics Research, San Gallicano Dermatologic Institute, IRCCS, Rome, Italy
| | - Arianna Mastrofrancesco
- Laboratory of Cutaneous Physiopathology and Integrated Center of Metabolomics Research, San Gallicano Dermatologic Institute, IRCCS, Rome, Italy
| | - Daniela Kovacs
- Laboratory of Cutaneous Physiopathology and Integrated Center of Metabolomics Research, San Gallicano Dermatologic Institute, IRCCS, Rome, Italy
| | - Barbara Bellei
- Laboratory of Cutaneous Physiopathology and Integrated Center of Metabolomics Research, San Gallicano Dermatologic Institute, IRCCS, Rome, Italy
| | - Stefania Briganti
- Laboratory of Cutaneous Physiopathology and Integrated Center of Metabolomics Research, San Gallicano Dermatologic Institute, IRCCS, Rome, Italy
| | - Vittoria Maresca
- Laboratory of Cutaneous Physiopathology and Integrated Center of Metabolomics Research, San Gallicano Dermatologic Institute, IRCCS, Rome, Italy
| | - Giorgia Cardinali
- Laboratory of Cutaneous Physiopathology and Integrated Center of Metabolomics Research, San Gallicano Dermatologic Institute, IRCCS, Rome, Italy
| | - Mauro Picardo
- Laboratory of Cutaneous Physiopathology and Integrated Center of Metabolomics Research, San Gallicano Dermatologic Institute, IRCCS, Rome, Italy.
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29
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Kim KI, Jeong HB, Ro H, Lee JH, Kim CD, Yoon TJ. Inhibitory effect of 5-iodotubercidin on pigmentation. Biochem Biophys Res Commun 2017; 490:1282-1286. [PMID: 28684314 DOI: 10.1016/j.bbrc.2017.07.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 07/02/2017] [Indexed: 01/20/2023]
Abstract
Melanin pigments are the primary contributors for the skin color. They are produced in melanocytes and then transferred to keratinocytes, eventually giving various colors on skin surface. Although many depigmenting and/or skin-lightening agents have been developed, there is still a growing demand on materials for reducing pigmentation. We attempted to find materials for depigmentation and/or skin-lightening using the small molecule compounds commercially available, and found that 5-iodotubercidin had inhibitory potential on pigmentation. When HM3KO melanoma cells were treated with 5-iodotubercidin, pigmentation was dramatically reduced. The 5-iodotubercidin decreased the protein level for pigmentation-related molecules such as MITF, tyrosinase, and TRP1. In addition, 5-iodotubercidin decreased the phosphorylation of CREB, while increased the phosphorylation of AKT and ERK. These data suggest that 5-iodotubercidin inhibits melanogenesis via the regulation of intracellular signaling related with pigmentation. Finally, 5-iodotubercidin markedly inhibited the melanogenesis of zebrafish embryos, an in vivo evaluation model for pigmentation. Together, these data suggest that 5-iodotubercidin can be developed as a depigmenting and/or skin-lightening agent.
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Affiliation(s)
- Kyung-Il Kim
- Department of Dermatology and Institute of Health Sciences, School of Medicine, Gyeongsang National University & Hospital, Jinju, Republic of Korea
| | - Hae Bong Jeong
- Department of Dermatology and Institute of Health Sciences, School of Medicine, Gyeongsang National University & Hospital, Jinju, Republic of Korea
| | - Hyunju Ro
- Department of Biological Sciences, College of Bioscience and Biotechnology, Chungnam National University, Daejeon, Republic of Korea
| | - Jeung-Hoon Lee
- Department of Dermatology, School of Medicine, Chungnam National University, Daejeon, Republic of Korea; Skin Med Co., Daejeon, Republic of Korea
| | - Chang Deok Kim
- Department of Dermatology, School of Medicine, Chungnam National University, Daejeon, Republic of Korea.
| | - Tae-Jin Yoon
- Department of Dermatology and Institute of Health Sciences, School of Medicine, Gyeongsang National University & Hospital, Jinju, Republic of Korea.
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30
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Nayman T, Bostan C, Logan P, Burnier MN. Uveal Melanoma Risk Factors: A Systematic Review of Meta-Analyses. Curr Eye Res 2017; 42:1085-1093. [PMID: 28494168 DOI: 10.1080/02713683.2017.1297997] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
PURPOSE There is currently no clinical risk-assessment tool allowing identification of patients at risk for developing uveal melanoma (UM) who might benefit from regular screening. As a first step toward the elaboration of such a tool, we systematically reviewed UM risk factors already established by meta-analysis. METHODS Two reviewers independently screened Pubmed, Medline, Embase, and Web of Science from their respective inception dates until July 2016 using a combination of keywords and MeSH terms. Eligible studies were meta-analyses or systematic reviews providing pooled odds ratios (ORs) of risk factors for UM development or sufficient information to calculate them. Methodological quality was evaluated using the Assessment of Multiple Systematic Reviews tool. RESULTS Four meta-analyses with a mean methodological quality score of 65.9% (min: 54.5%; max: 72.7%) were included. The following significant risk factors were identified: atypical cutaneous nevi (OR 2.82, 95% CI 1.10-7.26), welding (OR 2.05, 95% CI 1.20-3.51), occupational cooking (OR 1.81, 95% CI 1.33-2.46), fair skin color (OR 1.80, 95% CI 1.31-2.47), light eye color (OR 1.75, 95% CI 1.31-2.34), common cutaneous nevi (OR 1.74, 95% CI 1.27-2.39), propensity to sunburn (OR 1.64, 95% CI 1.29-2.09), iris nevi (OR 1.53, 95% CI 1.03-2.27), and cutaneous freckles (OR 1.27, 95% CI 1.09-1.49). Non-significant factors included outdoor leisure activity, occupational sunlight exposure, latitude of birth, and hair color. CONCLUSION Moderate quality of evidence determined nine significant risk factors for developing UM. Knowledge of these variables will assist researchers in the elaboration of a formal risk-assessment tool allowing clinicians to estimate susceptibility to the disease and necessity of regular screening.
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Affiliation(s)
- Taylor Nayman
- a The Henry C. Witelson Ocular Pathology Laboratory , McGill University , Montreal , QC , Canada.,b Faculty of Medicine , McGill University , Montreal , QC , Canada
| | - Cristina Bostan
- a The Henry C. Witelson Ocular Pathology Laboratory , McGill University , Montreal , QC , Canada.,c Department of Ophthalmology , University of Montreal , Montreal , QC , Canada
| | - Patrick Logan
- a The Henry C. Witelson Ocular Pathology Laboratory , McGill University , Montreal , QC , Canada
| | - Miguel N Burnier
- a The Henry C. Witelson Ocular Pathology Laboratory , McGill University , Montreal , QC , Canada.,d Department of Ophthalmology , McGill University , Montreal , QC , Canada
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31
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Herraiz C, Garcia-Borron JC, Jiménez-Cervantes C, Olivares C. MC1R signaling. Intracellular partners and pathophysiological implications. Biochim Biophys Acta Mol Basis Dis 2017; 1863:2448-2461. [PMID: 28259754 DOI: 10.1016/j.bbadis.2017.02.027] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 01/11/2017] [Accepted: 02/23/2017] [Indexed: 12/12/2022]
Abstract
The melanocortin-1 receptor (MC1R) preferentially expressed in melanocytes is best known as a key regulator of the synthesis of epidermal melanin pigments. Its paracrine stimulation by keratinocyte-derived melanocortins also activates DNA repair pathways and antioxidant defenses to build a complex, multifaceted photoprotective response. Many MC1R actions rely on cAMP-dependent activation of two transcription factors, MITF and PGC1α, but pleiotropic MC1R signaling also involves activation of mitogen-activated kinases and AKT. MC1R partners such as β-arrestins, PTEN and the E3 ubiquitin ligase MGRN1 differentially regulate these pathways. The MC1R gene is complex and polymorphic, with frequent variants associated with skin phenotypes and increased cancer risk. We review current knowledge of signaling from canonical MC1R, its splice isoforms and natural polymorphic variants. Recently discovered intracellular targets and partners are also discussed, to highlight the diversity of mechanisms that may contribute to normal and pathological variation of pigmentation and sensitivity to solar radiation-induced damage. This article is part of a Special Issue entitled: Melanocortin Receptors - edited by Ya-Xiong Tao.
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Affiliation(s)
- Cecilia Herraiz
- Department of Biochemistry and Molecular Biology, School of Medicine, University of Murcia and Instituto Murciano de Investigación Biosanitaria (IMIB), 30120 El Palmar, Murcia, Spain
| | - Jose C Garcia-Borron
- Department of Biochemistry and Molecular Biology, School of Medicine, University of Murcia and Instituto Murciano de Investigación Biosanitaria (IMIB), 30120 El Palmar, Murcia, Spain.
| | - Celia Jiménez-Cervantes
- Department of Biochemistry and Molecular Biology, School of Medicine, University of Murcia and Instituto Murciano de Investigación Biosanitaria (IMIB), 30120 El Palmar, Murcia, Spain
| | - Conchi Olivares
- Department of Biochemistry and Molecular Biology, School of Medicine, University of Murcia and Instituto Murciano de Investigación Biosanitaria (IMIB), 30120 El Palmar, Murcia, Spain
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32
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Płonka PM, Picardo M, Slominski AT. Does melanin matter in the dark? Exp Dermatol 2017; 26:595-597. [PMID: 27541811 DOI: 10.1111/exd.13171] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/11/2016] [Indexed: 12/26/2022]
Abstract
In living cells, melanin pigment is formed within melanosomes, which not only protect the cells from autodestruction, but also serve as second messenger organelles regulating important skin functions, with melanocytes acting as primary sensory and regulatory cells of the epidermis. Yet, one can argue that skin melanin, which may negatively affect cellular homeostasis in melanoma, really exerts protective functions. Consequently, the actual functions of melanin and the melanogenic pathway in skin biology remains enigmatic. Yet, the solution of this riddle seems simple - to check the actual influence of natural melanin on skin cells in the dark. Since many interesting hypotheses and theories put forward in this respect did not survive confrontation with the experiment, a leading pigment research group from Naples was brave to "jump off the cliff" by confronting theory with experimental reality. They showed that, in the dark, human hair-derived melanin promotes inflammatory responses in keratinocytes, lowers their viability, promotes oxidative stress, and that pheomelanin does so more strongly than eumelanin. Thus, pheomelanin hardly protects red-haired individuals, even when avoiding the sun. Black hairs do not do much better either, unless they undergo graying.
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Affiliation(s)
- Przemysław M Płonka
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
| | - Mauro Picardo
- Cutaneous Physiopathology Laboratory and Metabolomic Center, San Gallicano Dermatological Institute, Rome, Italy
| | - Andrzej T Slominski
- Department of Dermatology, University of Alabama at Birmingham, AL, USA.,Laboratory Service of the VA Medical Center, Birmingham, AL, USA
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33
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San-Jose LM, Ducrest AL, Ducret V, Simon C, Richter H, Wakamatsu K, Roulin A. MC1R variants affect the expression of melanocortin and melanogenic genes and the association between melanocortin genes and coloration. Mol Ecol 2016; 26:259-276. [PMID: 27664794 DOI: 10.1111/mec.13861] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 09/07/2016] [Accepted: 09/14/2016] [Indexed: 12/13/2022]
Abstract
The melanocortin-1 receptor (MC1R) gene influences coloration by altering the expression of genes acting downstream in the melanin synthesis. MC1R belongs to the melanocortin system, a genetic network coding for the ligands that regulate MC1R and other melanocortin receptors controlling different physiological and behavioural traits. The impact of MC1R variants on these regulatory melanocortin genes was never considered, even though MC1R mutations could alter the influence of these genes on coloration (e.g. by decreasing MC1R response to melanocortin ligands). Using barn owl growing feathers, we investigated the differences between MC1R genotypes in the (co)expression of six melanocortin and nine melanogenic-related genes and in the association between melanocortin gene expression and phenotype (feather pheomelanin content). Compared to the MC1R rufous allele, responsible for reddish coloration, the white allele was not only associated with an expected lower expression of melanogenic-related genes (TYR, TYRP1, OCA2, SLC45A2, KIT, DCT) but also with a lower MC1R expression and a higher expression of ASIP, the MC1R antagonist. More importantly, the expression of PCSK2, responsible for the maturation of the MC1R agonist, α-melanocyte-stimulating hormone, was positively related to pheomelanin content in MC1R white homozygotes but not in individuals carrying the MC1R rufous allele. These findings indicate that MC1R mutations not only alter the expression of melanogenic-related genes but also the association between coloration and the expression of melanocortin genes upstream of MC1R. This suggests that MC1R mutations can modulate the regulation of coloration by the pleiotropic melanocortin genes, potentially decoupling the often-observed associations between coloration and other phenotypes.
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Affiliation(s)
- Luis M San-Jose
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015, Lausanne, Switzerland
| | - Anne-Lyse Ducrest
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015, Lausanne, Switzerland
| | - Valérie Ducret
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015, Lausanne, Switzerland
| | - Céline Simon
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015, Lausanne, Switzerland
| | - Hannes Richter
- Centre for Integrative Genomics, Genomic Technologies Facility, University of Lausanne, Genopode Building, CH-1015, Lausanne, Switzerland
| | - Kazumasa Wakamatsu
- Department of Chemistry, Fujita Health University School of Health Sciences, Toyoake, Aichi, 470-1192, Japan
| | - Alexandre Roulin
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015, Lausanne, Switzerland
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Zouboulis CC, Picardo M, Ju Q, Kurokawa I, Törőcsik D, Bíró T, Schneider MR. Beyond acne: Current aspects of sebaceous gland biology and function. Rev Endocr Metab Disord 2016; 17:319-334. [PMID: 27726049 DOI: 10.1007/s11154-016-9389-5] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The sebaceous gland is most commonly found in association with a hair follicle. Its traditional function is the holocrine production of sebum, a complex mixture of lipids, cell debris, and other rather poorly characterized substances. Due to the gland's central role in acne pathogenesis, early research had focused on its lipogenic activity. Less studied aspects of the sebaceous gland, such as stem cell biology, the regulation of cellular differentiation by transcription factors, the significance of specific lipid fractions, the endocrine and specially the neuroendocrine role of the sebaceous gland, and its contribution to the innate immunity, the detoxification of the skin, and skin aging have only recently attracted the attention of researchers from different disciplines. Here, we summarize recent multidisciplinary progress in sebaceous gland research and discuss how sebaceous gland research may stimulate the development of novel therapeutic strategies targeting specific molecular pathways of the pathogenesis of skin diseases.
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Affiliation(s)
- Christos C Zouboulis
- Departments of Dermatology, Venereology, Allergology and Immunology, Dessau Medical Center, Auenweg 38, 06847, Dessau, Germany.
| | - Mauro Picardo
- San Gallicano Dermatologic Institute, IRCCS, Rome, Italy
| | - Qiang Ju
- Department of Dermatology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People's Republic of China
| | - Ichiro Kurokawa
- Department of Dermatology, Meiwa Hospital, Nishinomiya, Japan
| | - Dániel Törőcsik
- Department of Dermatology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Tamás Bíró
- Department of Immunology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Marlon R Schneider
- Institute of Molecular Animal Breeding and Biotechnology, Gene Center, LMU Munich, Munich, Germany
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Wnt/β-catenin signaling inhibitor ICG-001 enhances pigmentation of cultured melanoma cells. J Dermatol Sci 2016; 84:160-168. [PMID: 27567978 DOI: 10.1016/j.jdermsci.2016.08.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 08/02/2016] [Accepted: 08/16/2016] [Indexed: 12/22/2022]
Abstract
BACKGROUND Wnt/β-catenin signaling is important in development and differentiation of melanocytes. OBJECTIVE The object of this study was to evaluate the effects of several Wnt/β-catenin signaling inhibitors on pigmentation using melanoma cells. METHODS Melanoma cells were treated with Wnt/β-catenin signaling inhibitors, and then melanin content and tyrosinase activity were checked. RESULTS Although some inhibitors showed slight inhibition of pigmentation, we failed to observe potential inhibitory effect of those chemicals on pigmentation of HM3KO melanoma cells. Rather, one of powerful Wnt/β-catenin signaling inhibitors, ICG-001, increased the pigmentation of HM3KO melanoma cells. Pigmentation-enhancing effect of ICG-001 was reproducible in other melanoma cell line MNT-1. Consistent with these results. ICG-001 increased the expression of pigmentation-related genes, such as MITF, tyrosinase and TRP1. When ICG-001 was treated, the phosphorylation of CREB was significantly increased. In addition, ICG-001 treatment led to quick increase of intracellular cAMP level, suggesting that ICG-001 activated PKA signaling. The blockage of PKA signaling with pharmaceutical inhibitor H89 inhibited the ICG-001-induced pigmentation significantly. CONCLUSIONS These results suggest that PKA signaling is pivotal in pigmentation process itself, while the importance of Wnt/β-catenin signaling should be emphasized in the context of development and differentiation.
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Fajuyigbe D, Young AR. The impact of skin colour on human photobiological responses. Pigment Cell Melanoma Res 2016; 29:607-618. [PMID: 27454804 PMCID: PMC5132026 DOI: 10.1111/pcmr.12511] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 07/11/2016] [Indexed: 01/30/2023]
Abstract
Terrestrial solar ultraviolet radiation (UVR) exerts both beneficial and adverse effects on human skin. Epidemiological studies show a lower incidence of skin cancer in people with pigmented skins compared to fair skins. This is attributed to photoprotection by epidermal melanin, as is the poorer vitamin D status of those with darker skins. We summarize a wide range of photobiological responses across different skin colours including DNA damage and immunosuppression. Some studies show the generally modest photoprotective properties of melanin, but others show little or no effect. DNA photodamage initiates non‐melanoma skin cancer and is reduced by a factor of about 3 in pigmented skin compared with white skin. This suggests that if such a modest reduction in DNA damage can result in the significantly lower skin cancer incidence in black skin, the use of sunscreen protection might be extremely beneficial for susceptible population. Many contradictory results may be explained by protocol differences, including differences in UVR spectra and exposure protocols. We recommend that skin type comparisons be done with solar‐simulated radiation and standard erythema doses or physical doses (J/m2) rather than those based solely on clinical endpoints such as minimal erythema dose (MED).
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Affiliation(s)
- Damilola Fajuyigbe
- Division of Genetics and Molecular Medicine, Faculty of Life Sciences and Medicine, St John's Institute of Dermatology, King's College London, London, UK
| | - Antony R Young
- Division of Genetics and Molecular Medicine, Faculty of Life Sciences and Medicine, St John's Institute of Dermatology, King's College London, London, UK
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Functional Characterization of MC1R-TUBB3 Intergenic Splice Variants of the Human Melanocortin 1 Receptor. PLoS One 2015; 10:e0144757. [PMID: 26657157 PMCID: PMC4676704 DOI: 10.1371/journal.pone.0144757] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 11/23/2015] [Indexed: 12/29/2022] Open
Abstract
The melanocortin 1 receptor gene (MC1R) expressed in melanocytes is a major determinant of skin pigmentation. It encodes a Gs protein-coupled receptor activated by α-melanocyte stimulating hormone (αMSH). Human MC1R has an inefficient poly(A) site allowing intergenic splicing with its downstream neighbour Tubulin-β-III (TUBB3). Intergenic splicing produces two MC1R isoforms, designated Iso1 and Iso2, bearing the complete seven transmembrane helices from MC1R fused to TUBB3-derived C-terminal extensions, in-frame for Iso1 and out-of-frame for Iso2. It has been reported that exposure to ultraviolet radiation (UVR) might promote an isoform switch from canonical MC1R (MC1R-001) to the MC1R-TUBB3 chimeras, which might lead to novel phenotypes required for tanning. We expressed the Flag epitope-tagged intergenic isoforms in heterologous HEK293T cells and human melanoma cells, for functional characterization. Iso1 was expressed with the expected size. Iso2 yielded a doublet of Mr significantly lower than predicted, and impaired intracellular stability. Although Iso1- and Iso2 bound radiolabelled agonist with the same affinity as MC1R-001, their plasma membrane expression was strongly reduced. Decreased surface expression mostly resulted from aberrant forward trafficking, rather than high rates of endocytosis. Functional coupling of both isoforms to cAMP was lower than wild-type, but ERK activation upon binding of αMSH was unimpaired, suggesting imbalanced signaling from the splice variants. Heterodimerization of differentially labelled MC1R-001 with the splicing isoforms analyzed by co-immunoprecipitation was efficient and caused decreased surface expression of binding sites. Thus, UVR-induced MC1R isoforms might contribute to fine-tune the tanning response by modulating MC1R-001 availability and functional parameters.
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