51
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Itou T, Ito S, Wakamatsu K. Effects of Aging on Hair Color, Melanosomes, and Melanin Composition in Japanese Males and Their Sex Differences. Int J Mol Sci 2022; 23:ijms232214459. [PMID: 36430936 PMCID: PMC9693441 DOI: 10.3390/ijms232214459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 11/16/2022] [Accepted: 11/17/2022] [Indexed: 11/23/2022] Open
Abstract
In a previous study, we observed that the hair color of Japanese females darkens with age and that the causes of this are the increase in melanosome size, the amount of melanin, and the mol% of 5,6-dihydroxyindole (DHI) which has a high absorbance. In this study, we extended the same analyses to male hair to examine the sex differences in hair color, melanin composition, and melanosome morphology. Male hair also tended to darken with age, but it was darker than female hair in those of younger ages. Although there was no age dependence of DHI mol% in male hair, as with female hair, the melanosomes' sizes enlarged with age, the total melanin amount increased, and these findings were correlated with hair color. The analyses, considering age dependence, revealed that there were significant sex differences in the ratio of absorbance of dissolved melanin at the wavelength of 650 nm to 500 nm, in pheomelanin mol%, and in melanosome morphology parameters such as the minor axis. This may be the cause of the sex differences in hair color. Furthermore, the factors related to hair color were analyzed using all the data of the male and female hairs. The results suggested that total melanin amount, pheomelanin mol%, and DHI mol% correlated with hair color.
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Affiliation(s)
- Takashi Itou
- Kao Corporation, R&D—Hair Care Products Research, Tokyo 131-8501, Japan
| | - Shosuke Ito
- Institute for Melanin Chemistry, Fujita Health University, Toyoake 470-1192, Japan
- Correspondence: ; Tel.: +81-562-93-2000; Fax: +81-562-93-9847
| | - Kazumasa Wakamatsu
- Institute for Melanin Chemistry, Fujita Health University, Toyoake 470-1192, Japan
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52
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Are Plants Capable of Pheomelanin Synthesis? Gas Chromatography/Tandem Mass Spectrometry Characterization of Thermally Degraded Melanin Isolated from Echinacea purpurea. Processes (Basel) 2022. [DOI: 10.3390/pr10112465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Echinacea is a widely used plant medicine, valued especially for its well-documented ability to stimulate the immune system. It has been suggested that melanin could be one of the bioactive factors responsible for the immunostimulatory properties of the plant. The biological functions of melanin pigments are closely related to their chemical composition and structural features. The aim of this study was to characterize the melanin from Echinacea purpurea based on the analysis of thermal degradation products of the well-purified pigment extracted from the dried herb. The melanin was pyrolyzed, and the resulting products were separated by gas chromatography and identified using a triple quadrupole mass spectrometer operating in full scan and multiple reaction monitoring modes. Three groups of marker products were detected in the melanin pyrolysate: polyphenol derivatives, nitrogen-containing heterocycles devoid of sulfur, and benzothiazines/benzothiazoles. This suggests that E. purpurea produces three structurally different melanin pigments: allomelanin, eumelanin, and pheomelanin, which in turn may affect the biological activity of the herb. Our results provide the first-ever evidence that plants are capable of synthesizing pheomelanin, which until now, has only been described for representatives of the animal and fungal kingdoms.
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53
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Tian L, Li X, Ji H, Yu Q, Yang M, Guo L, Huang L, Gao W. Melanin-like nanoparticles: advances in surface modification and tumour photothermal therapy. J Nanobiotechnology 2022; 20:485. [PMCID: PMC9675272 DOI: 10.1186/s12951-022-01698-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 11/03/2022] [Indexed: 11/21/2022] Open
Abstract
Currently, tumor treatments are characterized by intelligence, diversity and personalization, but the therapeutic reagents used are often limited in clinical efficacy due to problems with water solubility, targeting, stability and multidrug resistance. To remedy these shortcomings, the application of multifunctional nanotechnology in the biomedical field has been widely studied. Synthetic melanin nanoparticles (MNPs) surfaces which contain highly reactive chemical groups such as carboxyl, hydroxyl and amine groups, can be used as a reaction platform on which to graft different functional components. In addition, MNPs easily adhere to substrate surface, and serve as a secondary reaction platform to modify it. The multifunctionality and intrinsic biocompatibility make melanin-like nanoparticles promising as a multifunctional and powerful nanoplatform for oncological applications. This paper first reviews the preparation methods, polymerization mechanisms and physicochemical properties of melanin including natural melanin and chemically synthesized melanin to guide scholars in MNP-based design. Then, recent advances in MNPs especially synthetic polydopamine (PDA) melanin for various medical oncological applications are systematically and thoroughly described, mainly focusing on bioimaging, photothermal therapy (PTT), and drug delivery for tumor therapy. Finally, based on the investigated literature, the current challenges and future directions for clinical translation are reasonably discussed, focusing on the innovative design of MNPs and further elucidation of pharmacokinetics. This paper is a timely and comprehensive and detailed study of the progress of MNPs in tumor therapy, especially PTT, and provides ideas for the design of personalized and customizable oncology nanomedicines to address the heterogeneity of the tumor microenvironment.
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Affiliation(s)
- Luyao Tian
- grid.33763.320000 0004 1761 2484Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, 300193 China
| | - Xia Li
- grid.33763.320000 0004 1761 2484Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, 300193 China
| | - Haixia Ji
- grid.33763.320000 0004 1761 2484Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, 300193 China
| | - Qing Yu
- grid.33763.320000 0004 1761 2484Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, 300193 China
| | - Mingjuan Yang
- grid.33763.320000 0004 1761 2484Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, 300193 China
| | - Lanping Guo
- grid.410318.f0000 0004 0632 3409National Resource Center for Chinese Materia Medica, Academy of Chinese Medical Sciences, Beijing, 100700 China
| | - Luqi Huang
- grid.410318.f0000 0004 0632 3409National Resource Center for Chinese Materia Medica, Academy of Chinese Medical Sciences, Beijing, 100700 China
| | - Wenyuan Gao
- grid.33763.320000 0004 1761 2484Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, 300193 China
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54
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Kalegari P, Leme DM, Disner GR, Cestari MM, de Lima Bellan D, Meira WV, Mazepa E, Martinez GR. High Melanin Content in Melanoma Cells Contributes to Enhanced DNA Damage after Rose Bengal Photosensitization. Photochem Photobiol 2022; 98:1355-1364. [PMID: 35398885 DOI: 10.1111/php.13632] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 04/03/2022] [Accepted: 04/06/2022] [Indexed: 11/30/2022]
Abstract
Melanoma is a type of tumor that originates from melanocytes. Irradiation of melanin with UVA and visible light can produce reactive oxygen species (ROS) such as singlet molecular oxygen (1 O2 ). The objective of this study was to examine DNA damage in melanoma cells (B16-F10) with different melanin contents, subjected to 1 O2 generation. To this end, we used the photosensitizer Rose Bengal acetate (RBAc) and irradiation with visible light (526 nm) (RBAc-PDT). We used the modified comet assay with the repair enzymes hOGG1 and T4 endonuclease V to detect the DNA damage associated with 8-oxo-7,8-dihydro-2'-deoxyguanosine and cyclobutane pyrimidine dimers lesions, respectively. We observed increased formation of hOGG1- and T4endoV-sensitive DNA lesions after light exposure (with or without RBAc). Furthermore, 18 h after irradiation, hOGG1-sensitive DNA lesions increased compared to that at the initial time point (0 h), which shows that a high melanin content contributes to post-irradiation formation of them, mainly via sustained oxidative stress, as confirmed by the measurement of ROS levels and activity of antioxidant enzymes. Contrastingly, the number of T4endoV-sensitive DNA lesions decreased over time (18 h). Our data indicate that in melanoma cells, a higher amount of melanin may affect DNA damage levels when subjected to RBAc-PDT.
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Affiliation(s)
- Paloma Kalegari
- Departamento de Bioquímica e Biologia Molecular, Programa de Pós-graduação em Ciências (Bioquímica), Setor de Ciências Biológicas, UFPR, Curitiba, Brazil
| | - Daniela Morais Leme
- Departamento de Genética, Setor de Ciências Biológicas, UFPR, Curitiba, Brazil
| | | | | | - Daniel de Lima Bellan
- Departamento de Biologia Celular, Setor de Ciências Biológicas, UFPR, Curitiba, Brazil
| | - Willian Vanderlei Meira
- Departamento de Bioquímica e Biologia Molecular, Programa de Pós-graduação em Ciências (Bioquímica), Setor de Ciências Biológicas, UFPR, Curitiba, Brazil
| | - Ester Mazepa
- Departamento de Bioquímica e Biologia Molecular, Programa de Pós-graduação em Ciências (Bioquímica), Setor de Ciências Biológicas, UFPR, Curitiba, Brazil
| | - Glaucia Regina Martinez
- Departamento de Bioquímica e Biologia Molecular, Programa de Pós-graduação em Ciências (Bioquímica), Setor de Ciências Biológicas, UFPR, Curitiba, Brazil
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55
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The photoprotection mechanism in the black-brown pigment eumelanin. Proc Natl Acad Sci U S A 2022; 119:e2212343119. [PMID: 36227945 PMCID: PMC9618045 DOI: 10.1073/pnas.2212343119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The natural black-brown pigment eumelanin protects humans from high-energy UV photons by absorbing and rapidly dissipating their energy before proteins and DNA are damaged. The extremely weak fluorescence of eumelanin points toward nonradiative relaxation on the timescale of picoseconds or shorter. However, the extreme chemical and physical complexity of eumelanin masks its photoprotection mechanism. We sought to determine the electronic and structural relaxation pathways in eumelanin using three complementary ultrafast optical spectroscopy methods: fluorescence, transient absorption, and stimulated Raman spectroscopies. We show that photoexcitation of chromophores across the UV-visible spectrum rapidly generates a distribution of visible excitation energies via ultrafast internal conversion among neighboring coupled chromophores, and then all these excitations relax on a timescale of ∼4 ps without transferring their energy to other chromophores. Moreover, these picosecond dynamics are shared by the monomeric building block, 5,6-dihydroxyindole-2-carboxylic acid. Through a series of solvent and pH-dependent measurements complemented by quantum chemical modeling, we show that these ultrafast dynamics are consistent with the partial excited-state proton transfer from the catechol hydroxy groups to the solvent. The use of this multispectroscopic approach allows the minimal functional unit in eumelanin and the role of exciton coupling and excited-state proton transfer to be determined, and ultimately reveals the mechanism of photoprotection in eumelanin. This knowledge has potential for use in the design of new soft optical components and organic sunscreens.
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56
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Kim M, Lim KM. Melanocytotoxic chemicals and their toxic mechanisms. Toxicol Res 2022; 38:417-435. [PMID: 36277364 PMCID: PMC9532501 DOI: 10.1007/s43188-022-00144-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 06/22/2022] [Accepted: 06/27/2022] [Indexed: 10/15/2022] Open
Abstract
Melanocyte cell death can lead to various melanocyte-related skin diseases including vitiligo and leukoderma. Melanocytotoxic chemicals are one of the most well-known causes of nongenetic melanocyte-related diseases, which induce melanocyte cell death through apoptosis. Various chemicals used in cosmetics, medicine, industry and food additives are known to induce melanocyte cell death, which poses a significant risk to the health of consumers and industrial workers. This review summarizes recently reported melanocytotoxic chemicals and their mechanisms of toxicity in an effort to provide insight into the development of safer chemicals.
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Affiliation(s)
- Minjeong Kim
- College of Pharmacy, Ewha Womans University, 52 Ewhayeodae-gil, Seodaemun-gu, Seoul, 03760 Republic of Korea
| | - Kyung-Min Lim
- College of Pharmacy, Ewha Womans University, 52 Ewhayeodae-gil, Seodaemun-gu, Seoul, 03760 Republic of Korea
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57
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Turak N, Monnier‐Corbel A, Gouret M, Frantz A. Urbanization shapes the relation between density and melanin‐based colouration in bird communities. OIKOS 2022. [DOI: 10.1111/oik.09313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Neyla Turak
- Sorbonne Univ., Univ. Paris‐Est Créteil, CNRS, INRA, IRD, Inst. of Ecology and Environmental Sciences – Paris Paris France
| | - Alice Monnier‐Corbel
- Sorbonne Univ., Univ. Paris‐Est Créteil, CNRS, INRA, IRD, Inst. of Ecology and Environmental Sciences – Paris Paris France
- Centre d'Ecologie et des Sciences de la Conservation (CESCO), Muséum National d'Histoire Naturelle, Centre National de la Recherche Scientifique, Sorbonne Univ. Paris France
- Emirates Center for Wildlife Propagation Missour Morocco
| | - Mélanie Gouret
- Sorbonne Univ., Univ. Paris‐Est Créteil, CNRS, INRA, IRD, Inst. of Ecology and Environmental Sciences – Paris Paris France
| | - Adrien Frantz
- Sorbonne Univ., Univ. Paris‐Est Créteil, CNRS, INRA, IRD, Inst. of Ecology and Environmental Sciences – Paris Paris France
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58
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Shen N, Ren J, Liu Y, Sun W, Li Y, Xin H, Cui Y. Natural edible pigments: a comprehensive review of resource, chemical classification, biosynthesis pathway, separated methods and application. Food Chem 2022; 403:134422. [DOI: 10.1016/j.foodchem.2022.134422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 09/03/2022] [Accepted: 09/25/2022] [Indexed: 10/14/2022]
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59
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Grass D, Beasley GM, Fischer MC, Selim MA, Zhou Y, Warren WS. Contrast mechanisms in pump-probe microscopy of melanin. OPTICS EXPRESS 2022; 30:31852-31862. [PMID: 36242259 PMCID: PMC9576283 DOI: 10.1364/oe.469506] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/04/2022] [Accepted: 08/05/2022] [Indexed: 05/27/2023]
Abstract
Pump-probe microscopy of melanin in tumors has been proposed to improve diagnosis of malignant melanoma, based on the hypothesis that aggressive cancers disaggregate melanin structure. However, measured signals of melanin are complex superpositions of multiple nonlinear processes, which makes interpretation challenging. Polarization control during measurement and data fitting are used to decompose signals of melanin into their underlying molecular mechanisms. We then identify the molecular mechanisms that are most susceptible to melanin disaggregation and derive false-coloring schemes to highlight these processes in biological tissue. We demonstrate that false-colored images of a small set of melanoma tumors correlate with clinical concern. More generally, our systematic approach of decomposing pump-probe signals can be applied to a multitude of different samples.
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Affiliation(s)
- David Grass
- Department of Chemistry,
Duke University, Durham, North Carolina, USA
| | - Georgia M. Beasley
- Department of Surgery, Duke University, Durham, North Carolina, USA
- Duke Cancer Institute, Duke University, Durham, North Carolina, USA
- Department of Medicine, Duke University, Durham, North Carolina, USA
| | - Martin C. Fischer
- Department of Chemistry,
Duke University, Durham, North Carolina, USA
- Department of Physics, Duke University, Durham, North Carolina, USA
| | - M. Angelica Selim
- Department of Pathology, Duke University, Durham, North Carolina, USA
| | - Yue Zhou
- Department of Chemistry,
Duke University, Durham, North Carolina, USA
| | - Warren S. Warren
- Department of Chemistry,
Duke University, Durham, North Carolina, USA
- Duke Cancer Institute, Duke University, Durham, North Carolina, USA
- Department of Physics, Duke University, Durham, North Carolina, USA
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA
- Department of Radiology, Duke University, Durham, North Carolina, USA
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60
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Gouda A, Masson A, Hoseinizadeh M, Soavi F, Santato C. Biosourced quinones for high-performance environmentally benign electrochemical capacitors via interface engineering. Commun Chem 2022; 5:98. [PMID: 36697677 PMCID: PMC9814668 DOI: 10.1038/s42004-022-00719-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 08/08/2022] [Indexed: 01/28/2023] Open
Abstract
Biosourced and biodegradable organic electrode materials respond to the need for sustainable storage of renewable energy. Here, we report on electrochemical capacitors based on electrodes made up of quinones, such as Sepia melanin and catechin/tannic acid (Ctn/TA), solution-deposited on carbon paper engineered to create high-performance interfaces. Sepia melanin and Ctn/TA on TCP electrodes exhibit a capacitance as high as 1355 mF cm-2 (452 F g-1) and 898 mF cm-2 (300 F g-1), respectively. Sepia melanin and Ctn/TA symmetric electrochemical capacitors operating in aqueous electrolytes exhibit up to 100% capacitance retention and 100% coulombic efficiency over 50,000 and 10,000 cycles at 150 mA cm-2 (10 A g-1), respectively. Maximum power densities as high as 1274 mW cm-2 (46 kW kg-1) and 727 mW cm-2 (26 kW kg-1) with maximum energy densities of 0.56 mWh cm-2 (20 Wh kg-1) and 0.65 mWh cm-2 (23 Wh kg-1) are obtained for Sepia melanin and Ctn/TA.
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Affiliation(s)
- Abdelaziz Gouda
- grid.183158.60000 0004 0435 3292Department of Engineering Physics, Polytechnique Montreal, C.P. 6079, Succ. Centre-ville, Montreal, Quebec H3C 3A7 Canada ,grid.17063.330000 0001 2157 2938Present Address: Now at, Solar Fuels Research Group, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, M5S 3H6 Canada
| | - Alexandre Masson
- grid.183158.60000 0004 0435 3292Department of Engineering Physics, Polytechnique Montreal, C.P. 6079, Succ. Centre-ville, Montreal, Quebec H3C 3A7 Canada
| | - Molood Hoseinizadeh
- grid.183158.60000 0004 0435 3292Department of Engineering Physics, Polytechnique Montreal, C.P. 6079, Succ. Centre-ville, Montreal, Quebec H3C 3A7 Canada
| | - Francesca Soavi
- grid.6292.f0000 0004 1757 1758Department of Chemistry “Giacomo Ciamician”, Alma Mater Studiorum Università di Bologna, Via Selmi, 2, Bologna, 40126 Italy
| | - Clara Santato
- grid.183158.60000 0004 0435 3292Department of Engineering Physics, Polytechnique Montreal, C.P. 6079, Succ. Centre-ville, Montreal, Quebec H3C 3A7 Canada
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61
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Handl J, Nyvltova P, Capek J, Cesla P, Hovsepyan A, Avetisyan S, Micankova P, Bruckova L, Stankova P, Knotkova K, Petrosyan T, Rousar T. The comparison of biological effects of bacterial and synthetic melanins in neuroblastoma cells. Food Chem Toxicol 2022; 168:113355. [PMID: 35952821 DOI: 10.1016/j.fct.2022.113355] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 07/28/2022] [Accepted: 08/03/2022] [Indexed: 11/26/2022]
Abstract
Melanins belong to a group of pigments of different structure and origin. They can be produced synthetically or isolated from living organisms. A number of studies have reported testing of various melanins in neurological studies providing different outcomes. Because the structure of melanins can have an effect on obtained results in cell toxicity studies, we present here our original study which aimed to compare the biological effects of bacterial melanin (biotechnologically obtained from B. thuringiensis) with that of synthetic melanin in neuroblastoma cells. Both melanins were structurally characterized in detail. After melanin treatment (0-200 μg/mL), cell viability, glutathione levels, cell morphology and respiration were assessed in SH-SY5Y cells. The structural analysis showed that bacterial melanin is more hydrophilic according to the presence of larger number of -OH moieties. After melanin treatment, we found that synthetic melanin at similar dosage caused always larger cell impairment compared to bacterial melanin. In addition, more severe toxic effect of synthetic melanin was found in mitochondria. In general, we conclude that more hydrophilic, bacterial melanin induced lower toxicity in neuroblastoma cells in comparison to synthetic melanin. Our findings can be useable for neuroscientific studies estimating the potential use for study of neuroprotection, neuromodulation or neurotoxicity.
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Affiliation(s)
- Jiri Handl
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10, Pardubice, Czech Republic
| | - Pavlina Nyvltova
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10, Pardubice, Czech Republic
| | - Jan Capek
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10, Pardubice, Czech Republic
| | - Petr Cesla
- Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10, Pardubice, Czech Republic
| | - Anichka Hovsepyan
- Scientific and Production Center "Armbiotechnology" SNPO NAS RA, 14 Gyurjyan St., Yerevan, Armenia
| | - Sona Avetisyan
- Scientific and Production Center "Armbiotechnology" SNPO NAS RA, 14 Gyurjyan St., Yerevan, Armenia
| | - Petra Micankova
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10, Pardubice, Czech Republic
| | - Lenka Bruckova
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10, Pardubice, Czech Republic
| | - Pavla Stankova
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10, Pardubice, Czech Republic
| | - Katerina Knotkova
- Department of Physical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10, Pardubice, Czech Republic
| | - Tigran Petrosyan
- Department of Physiology and Pathophysiology, Medical Institute, Yerevan Haybusak University, 6 Abelyan St., Yerevan, Armenia
| | - Tomas Rousar
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10, Pardubice, Czech Republic.
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62
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Capucciati A, Monzani E, Sturini M, Nicolis S, Zucca FA, Bubacco L, Bortolus M, Zecca L, Casella L. Water‐Soluble Melanin–Protein–Fe/Cu Conjugates Derived from Norepinephrine as Reliable Models for Neuromelanin of Human Brain
Locus Coeruleus. Angew Chem Int Ed Engl 2022; 61:e202204787. [DOI: 10.1002/anie.202204787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Indexed: 11/05/2022]
Affiliation(s)
- Andrea Capucciati
- Department of Chemistry University of Pavia Via Taramelli 12 27100 Pavia Italy
| | - Enrico Monzani
- Department of Chemistry University of Pavia Via Taramelli 12 27100 Pavia Italy
| | - Michela Sturini
- Department of Chemistry University of Pavia Via Taramelli 12 27100 Pavia Italy
| | - Stefania Nicolis
- Department of Chemistry University of Pavia Via Taramelli 12 27100 Pavia Italy
| | - Fabio A. Zucca
- Institute of Biomedical Technologies National Research Council of Italy Via Cervi 93 20054 Segrate (Milan) Italy
| | - Luigi Bubacco
- Department of Biology University of Padova Via Ugo Bassi 58/B 35128 Padova Italy
| | - Marco Bortolus
- Department of Chemical Science University of Padova Via Marzolo 1 35131 Padova Italy
| | - Luigi Zecca
- Institute of Biomedical Technologies National Research Council of Italy Via Cervi 93 20054 Segrate (Milan) Italy
| | - Luigi Casella
- Department of Chemistry University of Pavia Via Taramelli 12 27100 Pavia Italy
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63
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Argenziano R, Della Greca M, Panzella L, Napolitano A. A Straightforward Access to New Amides of the Melanin Precursor 5,6-Dihydroxyindole-2-carboxylic Acid and Characterization of the Properties of the Pigments Thereof. Molecules 2022; 27:4816. [PMID: 35956765 PMCID: PMC9369804 DOI: 10.3390/molecules27154816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 07/18/2022] [Accepted: 07/26/2022] [Indexed: 11/17/2022] Open
Abstract
We report herein an optimized procedure for preparation of carboxamides of 5,6-dihydroxyindole-2-carboxylic acid (DHICA), the main biosynthetic precursor of the skin photoprotective agents melanins, to get access to pigments with more favorable solubility properties with respect to the natural ones. The developed procedure was based on the use of a coupling agent (HATU/DIPEA) and required protection of the catechol function by easily removable acetyl groups. The O-acetylated compounds could be safely stored and taken to the reactive o-diphenol form just before use. Satisfactorily high yields (>85%) were obtained for all amides. The oxidative polymerization of the synthesized amides carried out in air in aqueous buffer at pH 9 afforded melanin-like pigmented materials that showed chromophores resembling those of DHICA-derived pigments, with a good covering of the UVA and the visible region, and additionally exhibited a good solubility in alcoholic solvents, a feature of great interest for the exploitation of these materials as ingredients of dermocosmetic formulations.
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Affiliation(s)
| | | | | | - Alessandra Napolitano
- Department of Chemical Sciences, University of Naples “Federico II”, Via Cintia 21, I-80126 Naples, Italy; (R.A.); (M.D.G.); (L.P.)
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64
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Fernandes S, Vyas C, Lim P, Pereira RF, Virós A, Bártolo P. 3D Bioprinting: An Enabling Technology to Understand Melanoma. Cancers (Basel) 2022; 14:cancers14143535. [PMID: 35884596 PMCID: PMC9318274 DOI: 10.3390/cancers14143535] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 07/04/2022] [Accepted: 07/12/2022] [Indexed: 02/06/2023] Open
Abstract
Melanoma is a potentially fatal cancer with rising incidence over the last 50 years, associated with enhanced sun exposure and ultraviolet radiation. Its incidence is highest in people of European descent and the ageing population. There are multiple clinical and epidemiological variables affecting melanoma incidence and mortality, such as sex, ethnicity, UV exposure, anatomic site, and age. Although survival has improved in recent years due to advances in targeted and immunotherapies, new understanding of melanoma biology and disease progression is vital to improving clinical outcomes. Efforts to develop three-dimensional human skin equivalent models using biofabrication techniques, such as bioprinting, promise to deliver a better understanding of the complexity of melanoma and associated risk factors. These 3D skin models can be used as a platform for patient specific models and testing therapeutics.
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Affiliation(s)
- Samantha Fernandes
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Oxford Road, Manchester M13 9PL, UK; (S.F.); (C.V.); (P.L.)
| | - Cian Vyas
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Oxford Road, Manchester M13 9PL, UK; (S.F.); (C.V.); (P.L.)
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Peggy Lim
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Oxford Road, Manchester M13 9PL, UK; (S.F.); (C.V.); (P.L.)
| | - Rúben F. Pereira
- ICBAS—Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313 Porto, Portugal;
- i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
- INEB—Instituto de Engenharia Biomédica, Universidade do Porto, 4200-135 Porto, Portugal
| | - Amaya Virós
- Skin Cancer and Ageing Laboratory, Cancer Research UK Manchester Institute, University of Manchester, Oxford Road, Manchester M13 9PL, UK;
| | - Paulo Bártolo
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Oxford Road, Manchester M13 9PL, UK; (S.F.); (C.V.); (P.L.)
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798, Singapore
- Correspondence: or
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Glagoleva AY, Vikhorev AV, Shmakov NA, Morozov SV, Chernyak EI, Vasiliev GV, Shatskaya NV, Khlestkina EK, Shoeva OY. Features of Activity of the Phenylpropanoid Biosynthesis Pathway in Melanin-Accumulating Barley Grains. FRONTIERS IN PLANT SCIENCE 2022; 13:923717. [PMID: 35898231 PMCID: PMC9310326 DOI: 10.3389/fpls.2022.923717] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 06/09/2022] [Indexed: 06/15/2023]
Abstract
Barley (Hordeum vulgare L.) grain pigmentation is caused by two types of phenolic compounds: anthocyanins (which are flavonoids) give a blue or purple color, and melanins (which are products of enzymatic oxidation and polymerization of phenolic compounds) give a black or brown color. Genes Ant1 and Ant2 determine the synthesis of purple anthocyanins in the grain pericarp, whereas melanins are formed under the control of the Blp1 gene in hulls and pericarp tissues. Unlike anthocyanin synthesis, melanin synthesis is poorly understood. The objective of the current work was to reveal features of the phenylpropanoid biosynthesis pathway functioning in melanin-accumulating barley grains. For this purpose, comparative transcriptomic and metabolomic analyses of three barley near-isogenic lines accumulating anthocyanins, melanins, or both in the grain, were performed. A comparative analysis of mRNA libraries constructed for three stages of spike development (booting, late milk, and early dough) showed transcriptional activation of genes encoding enzymes of the general phenylpropanoid pathway in all the lines regardless of pigmentation; however, as the spike matured, unique transcriptomic patterns associated with melanin and anthocyanin synthesis stood out. Secondary activation of transcription of the genes encoding enzymes of the general phenylpropanoid pathway together with genes of monolignol synthesis was revealed in the line accumulating only melanin. This pattern differs from the one observed in the anthocyanin-accumulating lines, where - together with the genes of general phenylpropanoid and monolignol synthesis pathways - flavonoid biosynthesis genes were found to be upregulated, with earlier activation of these genes in the line accumulating both types of pigments. These transcriptomic shifts may underlie the observed differences in concentrations of phenylpropanoid metabolites analyzed in the grain at a late developmental stage by high-performance liquid chromatography. Both melanin-accumulating lines showed an increased total level of benzoic acids. By contrast, anthocyanin-accumulating lines showed higher concentrations of flavonoids and p-coumaric and ferulic acids. A possible negative effect of melanogenesis on the total flavonoid content and a positive influence on the anthocyanin content were noted in the line accumulating both types of pigments. As a conclusion, redirection of metabolic fluxes in the phenylpropanoid biosynthesis pathway occurs when melanin is synthesized.
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Affiliation(s)
- Anastasiia Y. Glagoleva
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
- Kurchatov Genomics Center, ICG, SB RAS, Novosibirsk, Russia
| | - Alexander V. Vikhorev
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Nikolay A. Shmakov
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
- Kurchatov Genomics Center, ICG, SB RAS, Novosibirsk, Russia
| | - Sergey V. Morozov
- N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, SB RAS, Novosibirsk, Russia
| | - Elena I. Chernyak
- N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, SB RAS, Novosibirsk, Russia
| | - Gennady V. Vasiliev
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
- Kurchatov Genomics Center, ICG, SB RAS, Novosibirsk, Russia
| | - Natalia V. Shatskaya
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
- Kurchatov Genomics Center, ICG, SB RAS, Novosibirsk, Russia
| | - Elena K. Khlestkina
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
- N.I. Vavilov All-Russian Research Institute of Plant Genetic Resources, Saint Petersburg, Russia
| | - Olesya Y. Shoeva
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
- Kurchatov Genomics Center, ICG, SB RAS, Novosibirsk, Russia
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Hall MJ, Lopes-Ventura S, Neto MV, Charneca J, Zoio P, Seabra MC, Oliva A, Barral DC. Reconstructed human pigmented skin/epidermis models achieve epidermal pigmentation through melanocore transfer. Pigment Cell Melanoma Res 2022; 35:425-435. [PMID: 35325505 PMCID: PMC9543140 DOI: 10.1111/pcmr.13039] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 02/18/2022] [Accepted: 03/12/2022] [Indexed: 12/15/2022]
Abstract
The skin acts as a barrier to environmental insults and provides many vital functions. One of these is to shield DNA from harmful ultraviolet radiation, which is achieved by skin pigmentation arising as melanin is produced and dispersed within the epidermal layer. This is a crucial defence against DNA damage, photo‐ageing and skin cancer. The mechanisms and regulation of melanogenesis and melanin transfer involve extensive crosstalk between melanocytes and keratinocytes in the epidermis, as well as fibroblasts in the dermal layer. Although the predominant mechanism of melanin transfer continues to be debated and several plausible models have been proposed, we and others previously provided evidence for a coupled exo/phagocytosis model. Herein, we performed histology and immunohistochemistry analyses and demonstrated that a newly developed full‐thickness three‐dimensional reconstructed human pigmented skin model and an epidermis‐only model exhibit dispersed pigment throughout keratinocytes in the epidermis. Transmission electron microscopy revealed melanocores between melanocytes and keratinocytes, suggesting that melanin is transferred through coupled exocytosis/phagocytosis of the melanosome core, or melanocore, similar to our previous observations in human skin biopsies. We, therefore, present evidence that our in vitro models of pigmented human skin show epidermal pigmentation comparable to human skin. These findings have a high value for studies of skin pigmentation mechanisms and pigmentary disorders, whilst reducing the reliance on animal models and human skin biopsies.
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Affiliation(s)
- Michael J Hall
- CEDOC - Chronic Diseases Research Centre, NOVA Medical School, NMS, Universidade NOVA de Lisboa, Lisboa, Portugal
| | - Sara Lopes-Ventura
- Biomolecular Diagnostic Laboratory, Instituto de Tecnologia Química e Biológica (ITQB), Universidade Nova de Lisboa (UNL), Oeiras, Portugal
| | - Matilde V Neto
- CEDOC - Chronic Diseases Research Centre, NOVA Medical School, NMS, Universidade NOVA de Lisboa, Lisboa, Portugal
| | - João Charneca
- CEDOC - Chronic Diseases Research Centre, NOVA Medical School, NMS, Universidade NOVA de Lisboa, Lisboa, Portugal
| | - Patricia Zoio
- Biomolecular Diagnostic Laboratory, Instituto de Tecnologia Química e Biológica (ITQB), Universidade Nova de Lisboa (UNL), Oeiras, Portugal
| | - Miguel C Seabra
- CEDOC - Chronic Diseases Research Centre, NOVA Medical School, NMS, Universidade NOVA de Lisboa, Lisboa, Portugal.,UCL Institute of Ophthalmology, University College London, London, UK
| | - Abel Oliva
- Biomolecular Diagnostic Laboratory, Instituto de Tecnologia Química e Biológica (ITQB), Universidade Nova de Lisboa (UNL), Oeiras, Portugal.,Instituto de Biologia Experimental e Tecnológica (iBET), Oeiras, Portugal
| | - Duarte C Barral
- CEDOC - Chronic Diseases Research Centre, NOVA Medical School, NMS, Universidade NOVA de Lisboa, Lisboa, Portugal
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Capucciati A, Monzani E, Sturini M, Nicolis S, Zucca FA, Bubacco L, Bortolus M, Zecca L, Casella L. Water‐Soluble Melanin–Protein–Fe/Cu Conjugates Derived from Norepinephrine as Reliable Models for Neuromelanin of Human Brain
Locus Coeruleus. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202204787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Andrea Capucciati
- Department of Chemistry University of Pavia Via Taramelli 12 27100 Pavia Italy
| | - Enrico Monzani
- Department of Chemistry University of Pavia Via Taramelli 12 27100 Pavia Italy
| | - Michela Sturini
- Department of Chemistry University of Pavia Via Taramelli 12 27100 Pavia Italy
| | - Stefania Nicolis
- Department of Chemistry University of Pavia Via Taramelli 12 27100 Pavia Italy
| | - Fabio A. Zucca
- Institute of Biomedical Technologies National Research Council of Italy Via Cervi 93 20054 Segrate (Milan) Italy
| | - Luigi Bubacco
- Department of Biology University of Padova Via Ugo Bassi 58/B 35128 Padova Italy
| | - Marco Bortolus
- Department of Chemical Science University of Padova Via Marzolo 1 35131 Padova Italy
| | - Luigi Zecca
- Institute of Biomedical Technologies National Research Council of Italy Via Cervi 93 20054 Segrate (Milan) Italy
| | - Luigi Casella
- Department of Chemistry University of Pavia Via Taramelli 12 27100 Pavia Italy
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68
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Guo Y, Cariola A, Matera R, Gabbanini S, Valgimigli L. Real-time oxygen sensing as a powerful tool to investigate tyrosinase kinetics allows revising mechanism and activity of inhibition by glabridin. Food Chem 2022; 393:133423. [DOI: 10.1016/j.foodchem.2022.133423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/26/2022] [Accepted: 06/06/2022] [Indexed: 12/26/2022]
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Cabaço LC, Tomás A, Pojo M, Barral DC. The Dark Side of Melanin Secretion in Cutaneous Melanoma Aggressiveness. Front Oncol 2022; 12:887366. [PMID: 35619912 PMCID: PMC9128548 DOI: 10.3389/fonc.2022.887366] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 03/25/2022] [Indexed: 12/11/2022] Open
Abstract
Skin cancers are among the most common cancers worldwide and are increasingly prevalent. Cutaneous melanoma (CM) is characterized by the malignant transformation of melanocytes in the epidermis. Although CM shows lower incidence than other skin cancers, it is the most aggressive and responsible for the vast majority of skin cancer-related deaths. Indeed, 75% of patients present with invasive or metastatic tumors, even after surgical excision. In CM, the photoprotective pigment melanin, which is produced by melanocytes, plays a central role in the pathology of the disease. Melanin absorbs ultraviolet radiation and scavenges reactive oxygen/nitrogen species (ROS/RNS) resulting from the radiation exposure. However, the scavenged ROS/RNS modify melanin and lead to the induction of signature DNA damage in CM cells, namely cyclobutane pyrimidine dimers, which are known to promote CM immortalization and carcinogenesis. Despite triggering the malignant transformation of melanocytes and promoting initial tumor growth, the presence of melanin inside CM cells is described to negatively regulate their invasiveness by increasing cell stiffness and reducing elasticity. Emerging evidence also indicates that melanin secreted from CM cells is required for the immunomodulation of tumor microenvironment. Indeed, melanin transforms dermal fibroblasts in cancer-associated fibroblasts, suppresses the immune system and promotes tumor angiogenesis, thus sustaining CM progression and metastasis. Here, we review the current knowledge on the role of melanin secretion in CM aggressiveness and the molecular machinery involved, as well as the impact in tumor microenvironment and immune responses. A better understanding of this role and the molecular players involved could enable the modulation of melanin secretion to become a therapeutic strategy to impair CM invasion and metastasis and, hence, reduce the burden of CM-associated deaths.
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Affiliation(s)
- Luís C Cabaço
- Chronic Diseases Research Center (CEDOC), NOVA Medical School, NMS, Universidade NOVA de Lisboa, Lisbon, Portugal
| | - Ana Tomás
- Unidade de Investigação em Patobiologia Molecular (UIPM), Instituto Português de Oncologia de Lisboa Francisco Gentil E.P.E., Lisbon, Portugal
| | - Marta Pojo
- Unidade de Investigação em Patobiologia Molecular (UIPM), Instituto Português de Oncologia de Lisboa Francisco Gentil E.P.E., Lisbon, Portugal
| | - Duarte C Barral
- Chronic Diseases Research Center (CEDOC), NOVA Medical School, NMS, Universidade NOVA de Lisboa, Lisbon, Portugal
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70
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Ji RL, Tao YX. Melanocortin-1 receptor mutations and pigmentation: Insights from large animals. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2022; 189:179-213. [PMID: 35595349 DOI: 10.1016/bs.pmbts.2022.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The melanocortin-1 receptor (MC1R) is a G protein-coupled receptor expressed in cutaneous and hair follicle melanocytes, and plays a central role in coat color determination in vertebrates. Numerous MC1R variants have been identified in diverse species. Some of these variants have been associated with specific hair and skin color phenotypes in humans as well as coat color in animals. Gain-of-function mutations of the MC1R gene cause dominant or partially dominant black/dark coat color, and loss-of-function mutations of the MC1R gene cause recessive or partially recessive red/yellow/pale coat color phenotypes. These have been well documented in a large number of mammals, including human, dog, cattle, horse, sheep, pig, and fox. Higher similarities between large mammals and humans makes them better models to understand pathogenesis of human diseases caused by MC1R mutations. High identities in MC1Rs and similar variants identified in both humans and large mammals also provide an opportunity for receptor structure and function study. In this review, we aim to summarize the naturally occurring mutations of MC1R in humans and large animals.
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Affiliation(s)
- Ren-Lei Ji
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
| | - Ya-Xiong Tao
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States.
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71
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Nagatsu T, Nakashima A, Watanabe H, Ito S, Wakamatsu K. Neuromelanin in Parkinson's Disease: Tyrosine Hydroxylase and Tyrosinase. Int J Mol Sci 2022; 23:4176. [PMID: 35456994 PMCID: PMC9029562 DOI: 10.3390/ijms23084176] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/02/2022] [Accepted: 04/08/2022] [Indexed: 01/27/2023] Open
Abstract
Parkinson's disease (PD) is an aging-related disease and the second most common neurodegenerative disease after Alzheimer's disease. The main symptoms of PD are movement disorders accompanied with deficiency of neurotransmitter dopamine (DA) in the striatum due to cell death of the nigrostriatal DA neurons. Two main histopathological hallmarks exist in PD: cytosolic inclusion bodies termed Lewy bodies that mainly consist of α-synuclein protein, the oligomers of which produced by misfolding are regarded to be neurotoxic, causing DA cell death; and black pigments termed neuromelanin (NM) that are contained in DA neurons and markedly decrease in PD. The synthesis of human NM is regarded to be similar to that of melanin in melanocytes; melanin synthesis in skin is via DOPAquinone (DQ) by tyrosinase, whereas NM synthesis in DA neurons is via DAquinone (DAQ) by tyrosine hydroxylase (TH) and aromatic L-amino acid decarboxylase (AADC). DA in cytoplasm is highly reactive and is assumed to be oxidized spontaneously or by an unidentified tyrosinase to DAQ and then, synthesized to NM. Intracellular NM accumulation above a specific threshold has been reported to be associated with DA neuron death and PD phenotypes. This review reports recent progress in the biosynthesis and pathophysiology of NM in PD.
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Affiliation(s)
- Toshiharu Nagatsu
- Center for Research Promotion and Support, School of Medicine, Fujita Health University, Toyoake 470-1192, Aichi, Japan
| | - Akira Nakashima
- Department of Physiological Chemistry, School of Medicine, Fujita Health University, Toyoake 470-1192, Aichi, Japan;
| | - Hirohisa Watanabe
- Department of Neurology, School of Medicine, Fujita Health University, Toyoake 470-1192, Aichi, Japan;
| | - Shosuke Ito
- Institute for Melanin Chemistry, Fujita Health University, Toyoake 470-1192, Aichi, Japan; (S.I.); (K.W.)
| | - Kazumasa Wakamatsu
- Institute for Melanin Chemistry, Fujita Health University, Toyoake 470-1192, Aichi, Japan; (S.I.); (K.W.)
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72
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Elsayis A, Hassan SWM, Ghanem KM, Khairy H. Optimization of melanin pigment production from the halotolerant black yeast Hortaea werneckii AS1 isolated from solar salter in Alexandria. BMC Microbiol 2022; 22:92. [PMID: 35395716 PMCID: PMC8991569 DOI: 10.1186/s12866-022-02505-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 03/28/2022] [Indexed: 12/14/2022] Open
Abstract
Background Melanins are one of the magnificent natural pigments synthesized by a wide range of microorganisms including different species of fungi and bacteria. Marine black yeasts appear to be potential prospects for the synthesis of natural melanin pigment. As a result, the goal of this research was to isolate a marine black yeast melanin-producing strain and improve the culturing conditions in order to maximize the yield of such a valuable pigment. Results Among five locally isolated black yeast strains, the only one that demonstrated a potent remarkable melanin pigment production was identified using ITS rDNA as Hortaea werneckii AS1. The extracted pigment’s physiochemical characterization and analytical investigation with Ultraviolet-Visible (UV) spectrophotometry, Fourier Transform-Infrared spectroscopy (FTIR), and Scanning Electron Microscope (SEM) confirmed its nature as a melanin pigment. The data obtained from the polynomial model’s maximum point suggested that CaCl2, 1.125 g/L; trace element, 0.25 ml/L; and a culture volume 225 mL/500 mL at their optimal values were the critical three elements impacting melanin production. In comparison with the baseline settings, the response surface methodology (RSM) optimization approach resulted in a 2.0 - fold improvement in melanin output. Conclusions A maximum melanin yield of 0.938 g/L proved the halotolerant H. werneckii AS1 potentiality as a source for natural melanin pigment synthesis ‘when compared to some relevant black yeast strains’ and hence, facilitating its incorporation in a variety of pharmaceutical and environmental applications. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-022-02505-1.
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Affiliation(s)
- Asmaa Elsayis
- National Institute of Oceanography and Fisheries (NIOF), Cairo, Egypt
| | - Sahar W M Hassan
- National Institute of Oceanography and Fisheries (NIOF), Cairo, Egypt
| | - Khaled M Ghanem
- Department of Botany and Microbiology, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Heba Khairy
- Department of Botany and Microbiology, Faculty of Science, Alexandria University, Alexandria, Egypt.
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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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Paim TDP, Alves dos Santos C, Faria DAD, Paiva SR, McManus C. Genomic selection signatures in Brazilian sheep breeds reared in a tropical environment. Livest Sci 2022. [DOI: 10.1016/j.livsci.2022.104865] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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75
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Panzella L, Benning K, Nesbeth DN, Setaro B, D'Errico G, Napolitano A, d'Ischia M. Identification of black sturgeon caviar pigment as eumelanin. Food Chem 2022; 373:131474. [PMID: 34731814 DOI: 10.1016/j.foodchem.2021.131474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 10/15/2021] [Accepted: 10/24/2021] [Indexed: 11/29/2022]
Abstract
Reported herein is the purification of the pigment of black sturgeon caviar and its unambiguous identification as a typical eumelanin by means of chemical degradation coupled with electron paramagnetic resonance (EPR) evidence. HPLC and LC-MS analysis of oxidative degradation mixtures revealed the formation of pyrrole-2,3,5-tricarboxylic acid (PTCA), a specific marker of eumelanin pigments, in yields compatible with a 6.5% w/w pigment content. EPR spectral features and parameters were in close agreement with those reported for a typical natural eumelanin such as Sepia melanin from squid ink. The identification for the first time of eumelanin in a fish roe is expected to provide a novel molecular basis for the valorization of black caviar and production wastes thereof in food chemistry and diet.
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Affiliation(s)
- Lucia Panzella
- Department of Chemical Sciences, University of Naples "Federico II", Via Cintia 4, I-80126 Naples, Italy.
| | - Kenneth Benning
- Caviar Biotec, 563-565 Battersea Park Road, London SW11 3BL, United Kingdom
| | - Darren N Nesbeth
- Caviar Biotec, 563-565 Battersea Park Road, London SW11 3BL, United Kingdom; Department of Biochemical Engineering, University College London, Bernard Katz Building, London WC1H 6BT, United Kingdom
| | - Brunella Setaro
- Department of Chemical Sciences, University of Naples "Federico II", Via Cintia 4, I-80126 Naples, Italy
| | - Gerardino D'Errico
- Department of Chemical Sciences, University of Naples "Federico II", Via Cintia 4, I-80126 Naples, Italy
| | - Alessandra Napolitano
- Department of Chemical Sciences, University of Naples "Federico II", Via Cintia 4, I-80126 Naples, Italy
| | - Marco d'Ischia
- Department of Chemical Sciences, University of Naples "Federico II", Via Cintia 4, I-80126 Naples, Italy
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76
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Mobuchon L, Derrien AC, Houy A, Verrier T, Pierron G, Cassoux N, Milder M, Deleuze JF, Boland A, Scelo G, Cancel-Tassin G, Cussenot O, Rodrigues M, Noirel J, Machiela MJ, Stern MH. Different Pigmentation Risk Loci for High-Risk Monosomy 3 and Low-Risk Disomy 3 Uveal Melanomas. J Natl Cancer Inst 2022; 114:302-309. [PMID: 34424336 PMCID: PMC8826635 DOI: 10.1093/jnci/djab167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 07/06/2021] [Accepted: 08/19/2021] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Uveal melanoma (UM), a rare malignant tumor of the eye, is predominantly observed in populations of European ancestry. UMs carrying a monosomy 3 (M3) frequently relapse mainly in the liver, whereas UMs with disomy 3 (D3) are associated with more favorable outcome. Here, we explored the UM genetic predisposition factors in a large genome-wide association study (GWAS) of 1142 European UM patients and 882 healthy controls . METHODS We combined 2 independent datasets (Global Screening Array) with the dataset described in a previously published GWAS in UM (Omni5 array), which were imputed separately and subsequently merged. Patients were stratified according to their chromosome 3 status, and identified UM risk loci were tested for differential association with M3 or D3 subgroups. All statistical tests were 2-sided. RESULTS We recapitulated the previously identified risk locus on chromosome 5 on CLPTM1L (rs421284: odds ratio [OR] =1.58, 95% confidence interval [CI] = 1.35 to 1.86; P = 1.98 × 10-8) and identified 2 additional risk loci involved in eye pigmentation: IRF4 locus on chromosome 6 (rs12203592: OR = 1.76, 95% CI = 1.44 to 2.16; P = 3.55 × 10-8) and HERC2 locus on chromosome 15 (rs12913832: OR= 0.57, 95% CI = 0.48 to 0.67; P = 1.88 × 10-11). The IRF4 rs12203592 single-nucleotide polymorphism was found to be exclusively associated with risk for the D3 UM subtype (ORD3 = 2.73, 95% CI = 1.87 to 3.97; P = 1.78 × 10-7), and the HERC2 rs12913832 single-nucleotide polymorphism was exclusively associated with risk for the M3 UM subtype (ORM3 = 2.43, 95% CI = 1.79 to 3.29; P = 1.13 × 10-8). However, the CLPTM1L risk locus was equally statistically significant in both subgroups. CONCLUSIONS This work identified 2 additional UM risk loci known for their role in pigmentation. Importantly, we demonstrate that UM tumor biology and metastatic potential are influenced by patients' genetic backgrounds.
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Affiliation(s)
- Lenha Mobuchon
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M), Equipe Labellisée par la Ligue Nationale Contre le Cancer, Institut Curie, PSL Research University, Paris, France
| | - Anne-Céline Derrien
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M), Equipe Labellisée par la Ligue Nationale Contre le Cancer, Institut Curie, PSL Research University, Paris, France
| | - Alexandre Houy
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M), Equipe Labellisée par la Ligue Nationale Contre le Cancer, Institut Curie, PSL Research University, Paris, France
| | - Thibault Verrier
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M), Equipe Labellisée par la Ligue Nationale Contre le Cancer, Institut Curie, PSL Research University, Paris, France
| | - Gaëlle Pierron
- Somatic Genetic Unit, Department of Genetics, Institut Curie, PSL Research University, Paris, France
| | - Nathalie Cassoux
- Department of Ocular Oncology, Institut Curie, Paris, France
- Faculty of Medicine, University of Paris Descartes, Paris, France
| | - Maud Milder
- Inserm CIC BT 1418, Institut Curie, PSL Research University, Paris, France
| | - Jean-François Deleuze
- Université Paris-Saclay, CEA, Centre National de Recherche en Génomique Humaine, Evry, France
| | - Anne Boland
- Université Paris-Saclay, CEA, Centre National de Recherche en Génomique Humaine, Evry, France
| | - Ghislaine Scelo
- International Agency for Research on Cancer (IARC), Lyon, France
- Cancer Epidemiology Unit, Department of Medical Sciences, University of Turin, Turin, Italy
| | - Géraldine Cancel-Tassin
- CeRePP, Tenon Hospital, Paris, France
- Sorbonne University, GRC n°5 Predictive Onco-Urology, AP-HP, Tenon Hospital, Paris, France
| | - Olivier Cussenot
- CeRePP, Tenon Hospital, Paris, France
- Sorbonne University, GRC n°5 Predictive Onco-Urology, AP-HP, Tenon Hospital, Paris, France
| | - Manuel Rodrigues
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M), Equipe Labellisée par la Ligue Nationale Contre le Cancer, Institut Curie, PSL Research University, Paris, France
- Department of Medical Oncology, Institut Curie, PSL Research University, Paris, France
| | - Josselin Noirel
- Laboratoire GBCM (EA7528), CNAM, HESAM Université, Paris, France
| | - Mitchell J Machiela
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD 20892, USA
| | - Marc-Henri Stern
- Inserm U830, DNA Repair and Uveal Melanoma (D.R.U.M), Equipe Labellisée par la Ligue Nationale Contre le Cancer, Institut Curie, PSL Research University, Paris, France
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Galeb HA, Lamantia A, Robson A, König K, Eichhorn J, Baldock SJ, Ashton MD, Baum JV, Mort RL, Robinson BJ, Schacher FH, Chechik V, Taylor AM, Hardy JG. The Polymerization of Homogentisic Acid in Vitro as a Model for Pyomelanin Formation. MACROMOL CHEM PHYS 2022. [DOI: 10.1002/macp.202100489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Hanaa A. Galeb
- Department of Chemistry Lancaster University Lancaster LA1 4YB United Kingdom
- Department of Chemistry Science and Arts College, Rabigh Campus King Abdulaziz University Jeddah 21577 Saudi Arabia
| | - Angelo Lamantia
- Department of Physics Lancaster University Lancaster LA1 4YW United Kingdom
| | - Alexander Robson
- Department of Chemistry Lancaster University Lancaster LA1 4YB United Kingdom
| | - Katja König
- Institut für Organische und Makromolekulare Chemie Friedrich‐Schiller‐Universität Jena Lessingstraße 8 Jena 07743 Germany
| | - Jonas Eichhorn
- Institut für Organische und Makromolekulare Chemie Friedrich‐Schiller‐Universität Jena Lessingstraße 8 Jena 07743 Germany
| | - Sara J. Baldock
- Department of Chemistry Lancaster University Lancaster LA1 4YB United Kingdom
| | - Mark D. Ashton
- Department of Chemistry Lancaster University Lancaster LA1 4YB United Kingdom
| | - John V. Baum
- Department of Chemistry Lancaster University Lancaster LA1 4YB United Kingdom
| | - Richard L. Mort
- Division of Biomedical and Life Sciences Lancaster University Lancaster LA1 4YG United Kingdom
| | - Benjamin J. Robinson
- Department of Physics Lancaster University Lancaster LA1 4YW United Kingdom
- Materials Science Institute Lancaster University Lancaster LA1 4YB United Kingdom
| | - Felix H. Schacher
- Institut für Organische und Makromolekulare Chemie Friedrich‐Schiller‐Universität Jena Lessingstraße 8 Jena 07743 Germany
| | - Victor Chechik
- Department of Chemistry University of York Heslington, York YO10 5DD United Kingdom
| | - Adam M. Taylor
- Lancaster Medical School Lancaster University Lancaster LA1 4YW United Kingdom
| | - John G. Hardy
- Department of Chemistry Lancaster University Lancaster LA1 4YB United Kingdom
- Materials Science Institute Lancaster University Lancaster LA1 4YB United Kingdom
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78
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Pena AM, Decencière E, Brizion S, Sextius P, Koudoro S, Baldeweck T, Tancrède-Bohin E. In vivo melanin 3D quantification and z-epidermal distribution by multiphoton FLIM, phasor and Pseudo-FLIM analyses. Sci Rep 2022; 12:1642. [PMID: 35102172 PMCID: PMC8803839 DOI: 10.1038/s41598-021-03114-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 11/26/2021] [Indexed: 12/15/2022] Open
Abstract
Characterizing melanins in situ and determining their 3D z-epidermal distribution is paramount for understanding physiological/pathological processes of melanin neosynthesis, transfer, degradation or modulation with external UV exposure or cosmetic/pharmaceutical products. Multiphoton fluorescence intensity- and lifetime-based approaches have been shown to afford melanin detection, but how can one quantify melanin in vivo in 3D from multiphoton fluorescence lifetime (FLIM) data, especially since FLIM imaging requires long image acquisition times not compatible with 3D imaging in a clinical setup? We propose an approach combining (i) multiphoton FLIM, (ii) fast image acquisition times, and (iii) a melanin detection method called Pseudo-FLIM, based on slope analysis of autofluorescence intensity decays from temporally binned data. We compare Pseudo-FLIM to FLIM bi-exponential and phasor analyses of synthetic melanin, melanocytes/keratinocytes coculture and in vivo human skin. Using parameters of global 3D epidermal melanin density and z-epidermal distribution profile, we provide first insights into the in vivo knowledge of 3D melanin modulations with constitutive pigmentation versus ethnicity, with seasonality over 1 year and with topical application of retinoic acid or retinol on human skin. Applications of Pseudo-FLIM based melanin detection encompass physiological, pathological, or environmental factors-induced pigmentation modulations up to whitening, anti-photoaging, or photoprotection products evaluation.
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Affiliation(s)
- Ana-Maria Pena
- L'Oréal Research and Innovation, 1 Avenue Eugène Schueller, BP22, 93601, Aulnay-sous-Bois, France.
| | | | - Sébastien Brizion
- L'Oréal Research and Innovation, 1 Avenue Eugène Schueller, BP22, 93601, Aulnay-sous-Bois, France
| | - Peggy Sextius
- L'Oréal Research and Innovation, 1 Avenue Eugène Schueller, BP22, 93601, Aulnay-sous-Bois, France
| | - Serge Koudoro
- MINES ParisTech - PSL Research University, Fontainebleau, France
| | - Thérèse Baldeweck
- L'Oréal Research and Innovation, 1 Avenue Eugène Schueller, BP22, 93601, Aulnay-sous-Bois, France
| | - Emmanuelle Tancrède-Bohin
- L'Oréal Research and Innovation, Campus Charles Zviak RIO, 9 rue Pierre Dreyfus, Clichy, France
- Service de Dermatologie, Hôpital Saint-Louis, Paris, France
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79
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Slominski RM, Sarna T, Płonka PM, Raman C, Brożyna AA, Slominski AT. Melanoma, Melanin, and Melanogenesis: The Yin and Yang Relationship. Front Oncol 2022; 12:842496. [PMID: 35359389 PMCID: PMC8963986 DOI: 10.3389/fonc.2022.842496] [Citation(s) in RCA: 112] [Impact Index Per Article: 56.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 01/24/2022] [Indexed: 12/22/2022] Open
Abstract
Melanin pigment plays a critical role in the protection against the harmful effects of ultraviolet radiation and other environmental stressors. It is produced by the enzymatic transformation of L-tyrosine to dopaquinone and subsequent chemical and biochemical reactions resulting in the formation of various 5,6-dihydroxyindole-2-carboxylic acid (DHICA) and 5,6-dihydroxyindole (DHI) oligomers-main constituents of eumelanin, and benzothiazine and benzothiazole units of pheomelanin. The biosynthesis of melanin is regulated by sun exposure and by many hormonal factors at the tissue, cellular, and subcellular levels. While the presence of melanin protects against the development of skin cancers including cutaneous melanoma, its presence may be necessary for the malignant transformation of melanocytes. This shows a complex role of melanogenesis in melanoma development defined by chemical properties of melanin and the nature of generating pathways such as eu- and pheomelanogenesis. While eumelanin is believed to provide radioprotection and photoprotection by acting as an efficient antioxidant and sunscreen, pheomelanin, being less photostable, can generate mutagenic environment after exposure to the short-wavelength UVR. Melanogenesis by itself and its highly reactive intermediates show cytotoxic, genotoxic, and mutagenic activities, and it can stimulate glycolysis and hypoxia-inducible factor 1-alpha (HIF-1α) activation, which, combined with their immunosuppressive effects, can lead to melanoma progression and resistance to immunotherapy. On the other hand, melanogenesis-related proteins can be a target for immunotherapy. Interestingly, clinicopathological analyses on advanced melanomas have shown a negative correlation between tumor pigmentation and diseases outcome as defined by overall survival and disease-free time. This indicates a "Yin and Yang" role for melanin and active melanogenesis in melanoma development, progression, and therapy. Furthermore, based on the clinical, experimental data and diverse effects of melanogenesis, we propose that inhibition of melanogenesis in advanced melanotic melanoma represents a realistic adjuvant strategy to enhance immuno-, radio-, and chemotherapy.
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Affiliation(s)
- Radomir M Slominski
- Graduate Biomedical Sciences Program, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Tadeusz Sarna
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Przemysław M Płonka
- Department of Biophysics and Cancer Biology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Chander Raman
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Anna A Brożyna
- Department of Human Biology, Institute of Biology, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University, Toruń, Poland
| | - Andrzej T Slominski
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL, United States.,Pathology Laboratory Service, Veteran Administration Medical Center at Birmingham, Birmingham, AL, United States
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80
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Mocerino F, Pezzella A, Caruso U. Eumelanin pigment precursor 2-carboxy-5,6-dihydroxyindole and 2-amino-6-methylbenzothiazole chromophore integration towards melanin inspired chemoresponsive materials: the case of the Zn 2+ ion. RSC Adv 2022; 12:21050-21055. [PMID: 35919835 PMCID: PMC9301554 DOI: 10.1039/d2ra02616c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 07/09/2022] [Indexed: 11/21/2022] Open
Abstract
The 2-amino-6-methylbenzothiazole chromophore is introduced at the carboxyl group of the melanin precursor 2-carboxy-5,6-dihydroxyindole achieving a novel dihydroxyindole derivative with metal chelation properties not involving the catechol moiety.
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Affiliation(s)
- Fabio Mocerino
- Department of Chemical Sciences, University of Naples “Federico II” Via Cintia 4, I-80126 Naples, Italy
- Bioelectronics Task Force at University of Naples Federico II, Italy
| | - Alessandro Pezzella
- Bioelectronics Task Force at University of Naples Federico II, Italy
- Department of Physics “Ettore Pancini” Complesso Universitario Monte S. Angelo, Via Cintia, I-80126 Naples, Italy
| | - Ugo Caruso
- Department of Chemical Sciences, University of Naples “Federico II” Via Cintia 4, I-80126 Naples, Italy
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81
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Long J, Ding C, Yin G. Nickel/Brønsted acid dual-catalyzed regioselective C–H bond allylation of phenols with 1,3-dienes. Org Chem Front 2022. [DOI: 10.1039/d2qo00637e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A nickel/Brønsted acid dual-catalyzed C-H bond ortho-allylation of phenols with 1,3-dienes has been developed. This methodology is readily applicable to the modification of complex pharmaceutical molecules.
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Affiliation(s)
- Jiao Long
- The Institute for Advanced Studies, Wuhan University, Wuhan 430072, China
| | - Chao Ding
- The Institute for Advanced Studies, Wuhan University, Wuhan 430072, China
| | - Guoyin Yin
- The Institute for Advanced Studies, Wuhan University, Wuhan 430072, China
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82
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Bosch D, Wang J, Blancafort L. Fingerprint-based deep neural networks can model thermodynamic and optical properties of eumelanin DHI dimers. Chem Sci 2022; 13:8942-8946. [PMID: 36091209 PMCID: PMC9365084 DOI: 10.1039/d2sc02461f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 07/03/2022] [Indexed: 11/21/2022] Open
Abstract
Eumelanin is the biopolymer responsible for photoprotection in living beings and holds great promise as a smart biomaterial, but its detailed structure has not been characterized experimentally. Theoretical models are urgently needed to improve our knowledge of eumelanin's function and exploit its properties, but the enormous amount of possible oligomer components has made modelling not possible until now. Here we show that the stability and lowest vertical optical absorption of 5,6-dihydroxyindole (DHI) eumelanin dimer components can be modeled with deep neural networks, using fingerprint-like molecular representations as input. In spite of the modest data set size, average errors of only 6 and 9% for stability and S1 absorption energy are obtained. Our fingerprints code the connectivity and oxidation patterns of the dimers in a straightforward, unambiguous way and can be extended to larger oligomers. This proof-of-principle work shows that machine learning can be applied to help solve the structural challenge of melanin. Solving the challenge of melanin structure is important to realize its potential as smart biomaterial. By modeling the properties of eumelanin dimers we show that machine learning can be used to solve this problem.![]()
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Affiliation(s)
- Daniel Bosch
- Departament de Química, Institut de Química Computacional i Catàlisi, Universitat de Girona. Facultat de Ciències, C/M. A. Capmany 69, 17003 Girona, Spain
| | - Jun Wang
- Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials, Jiangsu Engineering Laboratory for Environment Functional Materials, Huaiyin Normal University, No. 111 West Changjiang Road, Huaian 223300, Jiangsu, P. R. China
| | - Lluís Blancafort
- Departament de Química, Institut de Química Computacional i Catàlisi, Universitat de Girona. Facultat de Ciències, C/M. A. Capmany 69, 17003 Girona, Spain
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83
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Barek H, Zhao H, Heath K, Veraksa A, Sugumaran M. Drosophila yellow-h encodes dopaminechrome tautomerase: A new enzyme in the eumelanin biosynthetic pathway. Pigment Cell Melanoma Res 2022; 35:26-37. [PMID: 34388859 DOI: 10.1111/pcmr.13008] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 08/03/2021] [Accepted: 08/10/2021] [Indexed: 11/26/2022]
Abstract
Melanin is a widely distributed phenolic pigment that is biosynthesized from tyrosine and its hydroxylated product, dopa, in all animals. However, recent studies reveal a significant deviation from this paradigm, as insects appear to use dopamine rather than dopa as the major precursor of melanin. This observation calls for a reconsideration of the insect melanogenic pathway. While phenoloxidases and laccases can oxidize dopamine for dopaminechrome production, the fate of dopaminechrome remains undetermined. Dopachrome decarboxylase/tautomerase, encoded by yellow-f/f2 of Drosophila melanogaster, can convert dopaminechrome into 5,6-dihydroxyindole, but the same enzyme from other organisms does not act on dopaminechrome, suggesting the existence of a specific dopaminechrome tautomerase (DPT). We now report the identification of this novel enzyme that biosynthesizes 5,6-dihydroxyindole from dopaminechrome in Drosophila. Dopaminechrome tautomerase acted on both dopaminechrome and N-methyl dopaminechrome but not on dopachrome or other aminochromes tested. Our biochemical and molecular studies reveal that this enzyme is encoded by the yellow-h gene, a member of the yellow gene family, and advance our understanding of the physiological functions of this gene family. Identification and characterization of DPT clarifies the precursor for melanin biosynthetic pathways and proves the existence of an independent melanogenic pathway in insects that utilizes dopamine as the primary precursor.
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Affiliation(s)
- Hanine Barek
- Department of Biology, University of Massachusetts Boston, Boston, Massachusetts, USA
| | - Heya Zhao
- Department of Biology, University of Massachusetts Boston, Boston, Massachusetts, USA
| | - Katerina Heath
- Department of Biology, University of Massachusetts Boston, Boston, Massachusetts, USA
| | - Alexey Veraksa
- Department of Biology, University of Massachusetts Boston, Boston, Massachusetts, USA
| | - Manickam Sugumaran
- Department of Biology, University of Massachusetts Boston, Boston, Massachusetts, USA
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84
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Bedran ZV, Zhukov SS, Abramov PA, Tyurenkov IO, Gorshunov BP, Mostert AB, Motovilov KA. Water-Activated Semiquinone Formation and Carboxylic Acid Dissociation in Melanin Revealed by Infrared Spectroscopy. Polymers (Basel) 2021; 13:4403. [PMID: 34960952 PMCID: PMC8705668 DOI: 10.3390/polym13244403] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/29/2021] [Accepted: 12/09/2021] [Indexed: 01/22/2023] Open
Abstract
Eumelanin is a widespread biomacromolecule pigment in the biosphere and has been widely investigated for numerous bioelectronics and energetic applications. Many of these applications depend on eumelanin's ability to conduct proton current at various levels of hydration. The origin of this behavior is connected to a comproportionation reaction between oxidized and reduced monomer moieties and water. A hydration-dependent FTIR spectroscopic study on eumelanin is presented herein, which allows for the first time tracking the comproportionation reaction via the gradual increase of the overall aromaticity of melanin monomers in the course of hydration. We identified spectral features associated with the presence of specific "one and a half" C𝌁O bonds, typical for o-semiquinones. Signatures of semiquinone monomers with internal hydrogen bonds and that carboxylic groups, in contrast to semiquinones, begin to dissociate at the very beginning of melanin hydration were indicated. As such, we suggest a modification to the common hydration-dependent conductivity mechanism and propose that the conductivity at low hydration is dominated by carboxylic acid protons, whereas higher hydration levels manifest semiquinone protons.
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Affiliation(s)
- Zakhar V. Bedran
- Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology, Institute Lane 9, 141701 Dolgoprudny, Russia; (Z.V.B.); (S.S.Z.); (P.A.A.); (I.O.T.); (B.P.G.)
| | - Sergey S. Zhukov
- Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology, Institute Lane 9, 141701 Dolgoprudny, Russia; (Z.V.B.); (S.S.Z.); (P.A.A.); (I.O.T.); (B.P.G.)
| | - Pavel A. Abramov
- Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology, Institute Lane 9, 141701 Dolgoprudny, Russia; (Z.V.B.); (S.S.Z.); (P.A.A.); (I.O.T.); (B.P.G.)
| | - Ilya O. Tyurenkov
- Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology, Institute Lane 9, 141701 Dolgoprudny, Russia; (Z.V.B.); (S.S.Z.); (P.A.A.); (I.O.T.); (B.P.G.)
| | - Boris P. Gorshunov
- Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology, Institute Lane 9, 141701 Dolgoprudny, Russia; (Z.V.B.); (S.S.Z.); (P.A.A.); (I.O.T.); (B.P.G.)
| | - A. Bernardus Mostert
- Department of Chemistry, Swansea University, Singleton Park, Swansea SA2 8PP, UK;
| | - Konstantin A. Motovilov
- Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology, Institute Lane 9, 141701 Dolgoprudny, Russia; (Z.V.B.); (S.S.Z.); (P.A.A.); (I.O.T.); (B.P.G.)
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85
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Sułkowski M, Kot M, Badyra B, Paluszkiewicz A, Płonka PM, Sarna M, Michalczyk-Wetula D, Zucca FA, Zecca L, Majka M. Highly Effective Protocol for Differentiation of Induced Pluripotent Stem Cells (iPS) into Melanin-Producing Cells. Int J Mol Sci 2021; 22:ijms222312787. [PMID: 34884599 PMCID: PMC8657900 DOI: 10.3390/ijms222312787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 11/06/2021] [Accepted: 11/18/2021] [Indexed: 11/16/2022] Open
Abstract
Melanin is a black/brown pigment present in abundance in human skin. Its main function is photo-protection of underlying tissues from harmful UV light. Natural sources of isolated human melanin are limited; thus, in vitro cultures of human cells may be a promising source of human melanin. Here, we present an innovative in vitro differentiation protocol of induced pluripotent stem cells (iPS) into melanin-producing cells, delivering highly pigmented cells in quantity and quality incomparably higher than any other methods previously described. Pigmented cells constitute over 90% of a terminally differentiated population and exhibit features characteristic for melanocytes, i.e., expression of specific markers such as MITF-M (microphthalmia-associated transcription factor isoform M), TRP-1 (tyrosinase-related protein 1), and TYR (tyrosinase) and accumulation of black pigment in organelles closely resembling melanosomes. Black pigment is unambiguously identified as melanin with features corresponding to those of melanin produced by typical melanocytes. The advantage of our method is that it does not require any sophisticated procedures and can be conducted in standard laboratory conditions. Moreover, our protocol is highly reproducible and optimized to generate high-purity melanin-producing cells from iPS cells; thus, it can serve as an unlimited source of human melanin for modeling human skin diseases. We speculate that FGF-8 might play an important role during differentiation processes toward pigmented cells.
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Affiliation(s)
- Maciej Sułkowski
- Department of Transplantation, Faculty of Medicine, Institute of Pediatrics, Jagiellonian University Medical College, 30-663 Cracow, Poland; (M.S.); (M.K.); (B.B.); (A.P.)
| | - Marta Kot
- Department of Transplantation, Faculty of Medicine, Institute of Pediatrics, Jagiellonian University Medical College, 30-663 Cracow, Poland; (M.S.); (M.K.); (B.B.); (A.P.)
| | - Bogna Badyra
- Department of Transplantation, Faculty of Medicine, Institute of Pediatrics, Jagiellonian University Medical College, 30-663 Cracow, Poland; (M.S.); (M.K.); (B.B.); (A.P.)
| | - Anna Paluszkiewicz
- Department of Transplantation, Faculty of Medicine, Institute of Pediatrics, Jagiellonian University Medical College, 30-663 Cracow, Poland; (M.S.); (M.K.); (B.B.); (A.P.)
| | - Przemysław M. Płonka
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Cracow, Poland; (P.M.P.); (M.S.); (D.M.-W.)
| | - Michał Sarna
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Cracow, Poland; (P.M.P.); (M.S.); (D.M.-W.)
| | - Dominika Michalczyk-Wetula
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Cracow, Poland; (P.M.P.); (M.S.); (D.M.-W.)
| | - Fabio A. Zucca
- Institute of Biomedical Technologies, National Research Council of Italy, 20054 Milan, Italy; (F.A.Z.); (L.Z.)
| | - Luigi Zecca
- Institute of Biomedical Technologies, National Research Council of Italy, 20054 Milan, Italy; (F.A.Z.); (L.Z.)
| | - Marcin Majka
- Department of Transplantation, Faculty of Medicine, Institute of Pediatrics, Jagiellonian University Medical College, 30-663 Cracow, Poland; (M.S.); (M.K.); (B.B.); (A.P.)
- Correspondence: ; Tel.: +48-12-659-15-93
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86
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Optimization of Solid-State Fermentation Extraction of Inonotus hispidus Fruiting Body Melanin. Foods 2021; 10:foods10122893. [PMID: 34945444 PMCID: PMC8700211 DOI: 10.3390/foods10122893] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 11/08/2021] [Accepted: 11/10/2021] [Indexed: 02/01/2023] Open
Abstract
Melanin has good nutritional and medicinal value; however, its extraction rate is extremely low. This study explored the edible and medicinal fungus Inonotus hispidus fruiting body melanin (IHFM) extraction process and solid-state fermentation conditions. The results showed that the best way to extract IHFM is the compound enzymatic method, with complex enzyme 26.63 mg/g, liquid material ratio 5:1, enzymatic hydrolysis 80 min, pH 4.61, and enzymolysis temperature at 36.07 °C. The yield of IHFM was 23.73 ± 0.57%, which was equivalent to 1.27 times before optimization. The best solid medium formula was normal pH, rice 20 g per cultivation bottle, maltose 22 g/L, beef extract 4.4 g/L, carbon-nitrogen ratio 5:1, and liquid-to-material ratio 1.1:1, where the IHFM yield was 31.80 ± 1.34%, which was equivalent to 1.7 times that before optimization. In summary, solid-state fermentation and extraction optimization greatly improved the yield of melanin, provided a reference to produce melanin, and laid a foundation for the development and utilization of melanin.
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87
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Tran-Ly AN, De France KJ, Rupper P, Schwarze FWMR, Reyes C, Nyström G, Siqueira G, Ribera J. Melanized-Cationic Cellulose Nanofiber Foams for Bioinspired Removal of Cationic Dyes. Biomacromolecules 2021; 22:4681-4690. [PMID: 34696590 DOI: 10.1021/acs.biomac.1c00942] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In recent years, water pollution has developed into a severe environmental and public health problem due to rapid urbanization and industrialization, especially in some developing countries. Finding solutions to tackle water pollution is urgently required and is of global importance. Currently, a range of water treatment methods are available; however, a water remediation process that is simple, inexpensive, eco-friendly, and effective for the removal of pollutants down to ppm/ppb concentrations has long been sought after. Herein, we describe a novel approach using fungal melanin for developing melanized-cationic cellulose nanofiber (melanized-C-CNF) foams that can successfully remove pollutants in water systems. The foam can be recycled several times while retaining its adsorption/desorption property, indicating high practicability for adsorbing the cationic dye crystal violet. This work highlights the opportunity to combine both the advanced features of sustainable polymers such as cellulose and the unique properties of fungal melanin to manufacture biohybrid composites for water purification.
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Affiliation(s)
- Anh N Tran-Ly
- Laboratory for Cellulose & Wood Materials, Empa─Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland.,Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, Stefano-Franscini Platz 5, Postfach 193, CH-8093 Zurich, Switzerland
| | - Kevin J De France
- Laboratory for Cellulose & Wood Materials, Empa─Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Patrick Rupper
- Laboratory for Advanced Fibers, Empa─Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Francis W M R Schwarze
- Laboratory for Cellulose & Wood Materials, Empa─Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Carolina Reyes
- Laboratory for Cellulose & Wood Materials, Empa─Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Gustav Nyström
- Laboratory for Cellulose & Wood Materials, Empa─Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Gilberto Siqueira
- Laboratory for Cellulose & Wood Materials, Empa─Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Javier Ribera
- Laboratory for Cellulose & Wood Materials, Empa─Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
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88
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Calabrese C, Liotta LF, Soumoy L, Aprile C, Giacalone F, Gruttadauria M. New Hybrid Organic‐inorganic Multifunctional Materials Based on Polydopamine‐like Chemistry. ASIAN J ORG CHEM 2021. [DOI: 10.1002/ajoc.202100443] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Carla Calabrese
- Department of Biological Chemical and Pharmaceutical Sciences and Technologies University of Palermo Viale delle Scienze, Ed. 17 90128 Palermo Italy
| | - Leonarda Francesca Liotta
- Istituto per lo Studio dei Materiali Nanostrutturati ISMN-CNR Via Ugo La Malfa 153 90146 Palermo Italy
| | - Loraine Soumoy
- Laboratory of Applied Materials Chemistry (CMA) Department of Chemistry University of Namur 61 rue de Bruxelles 5000 Namur Belgium
| | - Carmela Aprile
- Laboratory of Applied Materials Chemistry (CMA) Department of Chemistry University of Namur 61 rue de Bruxelles 5000 Namur Belgium
| | - Francesco Giacalone
- Department of Biological Chemical and Pharmaceutical Sciences and Technologies University of Palermo Viale delle Scienze, Ed. 17 90128 Palermo Italy
| | - Michelangelo Gruttadauria
- Department of Biological Chemical and Pharmaceutical Sciences and Technologies University of Palermo Viale delle Scienze, Ed. 17 90128 Palermo Italy
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89
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Kowalska J, Banach K, Beberok A, Rok J, Rzepka Z, Wrześniok D. The Biochemical and Molecular Analysis of Changes in Melanogenesis Induced by UVA-Activated Fluoroquinolones-In Vitro Study on Human Normal Melanocytes. Cells 2021; 10:cells10112900. [PMID: 34831123 PMCID: PMC8616096 DOI: 10.3390/cells10112900] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 10/15/2021] [Accepted: 10/25/2021] [Indexed: 11/16/2022] Open
Abstract
Fluoroquinolones cause phototoxic reactions, manifested as different types of skin lesions, including hyperpigmentation. The disturbances of melanogenesis indicate that fluoroquinolones may affect cellular processes in melanocytes. It has been reported that these antibiotics may bind with melanin and accumulate in pigmented cells. The study aimed to examine the changes in melanogenesis in human normal melanocytes exposed to UVA radiation and treated with lomefloxacin and moxifloxacin, the most and the least fluoroquinolone, respectively. The obtained results demonstrated that both tested fluoroquinolones inhibited melanogenesis through a decrease in tyrosinase activity and down-regulation of tyrosinase and microphthalmia-associated transcription factor production. Only lomefloxacin potentiated UVA-induced melanogenesis. Under UVA irradiation lomefloxacin significantly enhanced melanin content and tyrosinase activity in melanocytes, although the drug did not cause an increased expression of tyrosinase or microphthalmia-associated transcription factor. The current studies revealed that phototoxic activity of fluoroquinolones is associated with alterations in the melanogenesis process. The difference in phototoxic potential of fluoroquinolones derivatives may be connected with various effects on UVA-induced events at a cellular level.
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90
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Kokita T, Ueno K, Yamasaki YY, Matsuda M, Tabata R, Nagano AJ, Mishina T, Watanabe K. Gudgeon fish with and without genetically determined countershading coexist in heterogeneous littoral environments of an ancient lake. Ecol Evol 2021; 11:13283-13294. [PMID: 34646469 PMCID: PMC8495823 DOI: 10.1002/ece3.8050] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 08/02/2021] [Accepted: 08/09/2021] [Indexed: 11/16/2022] Open
Abstract
Countershading, characterized by a darker dorsal surface and lighter ventral surface, is common among many animals. This dorsoventral pigment polarity is often thought to be adaptive coloration for camouflage. By contrast, noncountershaded (melanistic) morphs often occur within a species due to genetic color polymorphism in terrestrial animals. However, the polymorphism with either countershaded or melanistic morphs is poorly known in wild aquatic animals. This study explored the genetic nature of diverged color morphs of a lineage of gudgeon fish (genus Sarcocheilichthys) in the ancient Lake Biwa and propose this system as a novel model for testing hypotheses of functional aspects of countershading and its loss in aquatic environments. This system harbors two color morphs that have been treated taxonomically as separate species; Sarcocheilichthys variegatus microoculus which occurs throughout the littoral zone and Sarcocheilichthys biwaensis which occurs in and around rocky areas. First, we confirmed that the divergence of dorsoventral color patterns between the two morphs is under strict genetic control at the levels of chromatophore distribution and melanin-related gene expression under common garden rearing. The former morph displayed sharp countershading coloration, whereas the latter morph exhibited a strong tendency toward its loss. The crossing results indicated that this divergence was likely controlled by a single locus in a two-allele Mendelian inheritance pattern. Furthermore, our population genomic and genome-wide association study analyses detected no genome-wide divergence between the two morphs, except for one region near a locus that may be associated with the color divergence. Thus, these morphs are either in a state of intraspecific color polymorphism or two incipient species. Evolutionary forces underlying this polymorphism appear to be associated with heterogeneous littoral environments in this lake. Future ecological genomic research will provide insight into adaptive functions of this widespread coloration, including the eco-evolutionary drivers of its loss, in the aquatic world.
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Affiliation(s)
- Tomoyuki Kokita
- Faculty of Marine Science and TechnologyFukui Prefectural UniversityObamaJapan
| | - Kohtaro Ueno
- Faculty of Marine Science and TechnologyFukui Prefectural UniversityObamaJapan
| | | | | | | | - Atsushi J. Nagano
- Faculty of AgricultureRyukoku UniversityOtsuJapan
- Institute for Advanced BiosciencesKeio UniversityTsuruokaJapan
| | - Tappei Mishina
- Laboratory for Chromosome SegregationRIKEN Center for Biosystems Dynamics ResearchKobeJapan
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91
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Martinez-Gonzalez JA, Cavaye H, McGettrick JD, Meredith P, Motovilov KA, Mostert AB. Interfacial water morphology in hydrated melanin. SOFT MATTER 2021; 17:7940-7952. [PMID: 34378618 DOI: 10.1039/d1sm00777g] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The importance of electrically functional biomaterials is increasing as researchers explore ways to utilise them in novel sensing capacities. It has been recognised that for many of these materials the state of hydration is a key parameter that can heavily affect the conductivity, particularly those that rely upon ionic or proton transport as a key mechanism. However, thus far little attention has been paid to the nature of the water morphology in the hydrated state and the concomitant ionic conductivity. Presented here is an inelastic neutron scattering (INS) experiment on hydrated eumelanin, a model bioelectronic material, in order to investigate its 'water morphology'. We develop a rigorous new methodology for performing hydration dependent INS experiments. We also model the eumelanin dry spectra with a minimalist approach whereas for higher hydration levels we are able to obtain difference spectra to extract out the water scattering signal. A key result is that the physi-sorbed water structure within eumelanin is dominated by interfacial water with the number of water layers between 3-5, and no bulk water. We also detect for the first time, the potential signatures for proton cations, most likely the Zundel ion, within a biopolymer/water system. These new signatures may be general for soft proton ionomer systems, if the systems are comprised of only interfacial water within their structure. The nature of the water morphology opens up new questions about the potential ionic charge transport mechanisms within hydrated bioelectronics materials.
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Affiliation(s)
- J A Martinez-Gonzalez
- ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, Science and Technology Facilities Council, Didcot, OX11 0QX, UK
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92
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Mavridi-Printezi A, Menichetti A, Guernelli M, Montalti M. The Photophysics and Photochemistry of Melanin- Like Nanomaterials Depend on Morphology and Structure. Chemistry 2021; 27:16309-16319. [PMID: 34505731 PMCID: PMC9291563 DOI: 10.1002/chem.202102479] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Indexed: 12/12/2022]
Abstract
Melanin‐like nanomaterials have found application in a large variety of high economic and social impact fields as medicine, energy conversion and storage, photothermal catalysis and environmental remediation. These materials have been used mostly for their optical and electronic properties, but also for their high biocompatibility and simplicity and versatility of preparation. Beside this, their chemistry is complex and it yields structures with different molecular weight and composition ranging from oligomers, to polymers as well as nanoparticles (NP). The comprehension of the correlation of the different compositions and morphologies to the optical properties of melanin is still incomplete and challenging, even if it is fundamental also from a technological point of view. In this minireview we focus on scientific papers, mostly recent ones, that indeed examine the link between composition and structural feature and photophysical and photochemical properties proposing this approach as a general one for future research.
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Affiliation(s)
| | - Arianna Menichetti
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via Selmi 2, 40126, Bologna, Italy
| | - Moreno Guernelli
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via Selmi 2, 40126, Bologna, Italy
| | - Marco Montalti
- Department of Chemistry "Giacomo Ciamician", University of Bologna, Via Selmi 2, 40126, Bologna, Italy
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93
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Wakamatsu K, Munyard K, Oddie C, Ito S. Photobleached Oxidative Degradation of Melanins: Chemical Characterization of Melanins Present in Alpaca Fiber. Photochem Photobiol 2021; 97:1493-1497. [PMID: 34435360 DOI: 10.1111/php.13511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 08/23/2021] [Indexed: 11/28/2022]
Abstract
In order to characterize the phenotype and to examine the effects of sun exposure on the color and structure of eumelanin (EM) and pheomelanin (PM) in alpaca fibers, we applied Soluene-350 solubilization, alkaline hydrogen peroxide oxidation (AHPO) and hydroiodic acid (HI) hydrolysis to the base and tip fibers of 20 true-black (TB) and 20 warm-black (WB) alpacas. We analyzed absorbances at 500 nm (A500) and 650 nm (A650), Free and Total pyrrole-2,3,5-tricarboxylic acid (PTCA), 2,3,4,5-tetracarboxylic acid (PTeCA) as degradative products from EM, and 4-amino-3-hydroxyphenylalanine (4-AHP), 3-amino-4-hydroxyphenylalanine (3-AHP) and thiazole-2,4,5-tricarboxylic acid (TTCA) as degradative products from PM. We found that the ratio of PTeCA/Total PTCA increased significantly from the base to the tip in both colors of alpaca fibers, while the ratios of A650/A500 and 4-AHP/3-AHP decreased significantly. These results show that structures made of both EM and PM in alpaca fibers are modified significantly by sun exposure inducing color change. This study indicates that the ratios of A650/A500, PTeCA/Total PTCA and 4-AHP/3-AHP are highly sensitive markers of color change and photodegradation of EM and PM, respectively.
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Affiliation(s)
- Kazumasa Wakamatsu
- Institute for Melanin Chemistry, Fujita Health University, Toyoake, Aichi, Japan
| | - Kylie Munyard
- Curtin Medical School, Faculty of Health Sciences, Curtin University, Perth, WA, Australia
| | - Carolyn Oddie
- Curtin Medical School, Faculty of Health Sciences, Curtin University, Perth, WA, Australia
| | - Shosuke Ito
- Institute for Melanin Chemistry, Fujita Health University, Toyoake, Aichi, Japan
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94
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Olennikov DN, Kirillina CS, Chirikova NK. Water-Soluble Melanoidin Pigment as a New Antioxidant Component of Fermented Willowherb Leaves ( Epilobium angustifolium). Antioxidants (Basel) 2021; 10:1300. [PMID: 34439548 PMCID: PMC8389334 DOI: 10.3390/antiox10081300] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/13/2021] [Accepted: 08/15/2021] [Indexed: 01/06/2023] Open
Abstract
Willowherb (Epilobium angustifolium L., family Onagraceae) is a well-known food and medicinal plant used after fermentation as a source of beverages with high antioxidant potential. Despite this long history of use, only a few papers have described the chemical profile and bioactivity of fermented willowherb tea in general. To understand the basic metabolic differences of non-fermented and fermented E. angustifolium leaves, we used general chemical analysis, high-performance liquid chromatography with photodiode array detection and electrospray ionization triple quadrupole mass spectrometric detection assay, and an isolation technique. As a result, the content of 14 chemical groups of compounds was compared in the two plant materials; 59 compounds were detected, including 36 new metabolites; and a new water-soluble phenolic polymer of melanoidin nature was isolated and characterized. The fundamental chemical shifts in fermented E. angustifolium leaves relate mainly to the decrease of ellagitannin content, while there is an increase of melanoidin percentage and saving of the antioxidant potential, despite the significant changes detected. The strong antioxidative properties of the new melanoidin were revealed in a series of in vitro bioassays, and a simulated gastrointestinal and colonic digestion model demonstrated the stability of melanoidin and its antioxidant activity. Finally, we concluded that the new melanoidin is a basic antioxidant of the fermented leaves of E. angustifolium, and it can be recommended for additional study as a promising food and medicinal antioxidant agent.
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Affiliation(s)
- Daniil N. Olennikov
- Laboratory of Medical and Biological Research, Institute of General and Experimental Biology, Siberian Division, Russian Academy of Science, 670047 Ulan-Ude, Russia
| | - Christina S. Kirillina
- Department of Biology, Institute of Natural Sciences, North-Eastern Federal University, 677027 Yakutsk, Russia; (C.S.K.); (N.K.C.)
| | - Nadezhda K. Chirikova
- Department of Biology, Institute of Natural Sciences, North-Eastern Federal University, 677027 Yakutsk, Russia; (C.S.K.); (N.K.C.)
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95
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Wang J, Blancafort L. Stability and Optical Absorption of a Comprehensive Virtual Library of Minimal Eumelanin Oligomer Models**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202106289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jun Wang
- Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials Jiangsu Engineering Laboratory for Environment Functional Materials School of Chemistry and Chemical Engineering Huaiyin Normal University No.111 West Changjiang Road Huaian 223300 Jiangsu Province P. R. China
- Institut de Química Computacional i Catàlisi and Departament de Química Universitat de Girona, Facultat de Ciències C/M. A. Capmany 69 17003 Girona Spain
| | - Lluís Blancafort
- Institut de Química Computacional i Catàlisi and Departament de Química Universitat de Girona, Facultat de Ciències C/M. A. Capmany 69 17003 Girona Spain
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96
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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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97
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Understanding the way eumelanin works: A unique example of properties and skills driven by molecular heterogeneity. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123952] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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98
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Shen Y, Liu J, Wang Y, Qi W, Su R, He Z. Colorful Pigments for Hair Dyeing Based on Enzymatic Oxidation of Tyrosine Derivatives. ACS APPLIED MATERIALS & INTERFACES 2021; 13:34851-34864. [PMID: 34260221 DOI: 10.1021/acsami.1c06881] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Melanin exists widely in nature and can afford a variety of colors from black to brown and red according to chemical structure differences and specific mixtures. Inspired by nature, this work reports that tyrosine derivatives with different protecting groups at its N- or C-terminal can be enzymatically oxidized into melanin-like pigments with a wide range of colors. The emergence of colorful pigments can be attributed to the incomplete enzymatic oxidation and polymerization caused by the chemical premodification of the tyrosine molecule. The pigments can be deposited on the surface of the hair to obtain a series of colorful and saturated hair dye effects. Moreover, after the pigments were coated on the hair, we can further deposit silver nanoparticles through in situ reduction, making these coatings have anti-inflammatory and antibacterial potential, thereby expanding their potential use for people with low immunity or those who work in hospitals. This work proposes a green and effective way to synthesize colorful pigments with great potential applications in the hair dying and cosmetic industries.
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Affiliation(s)
- Yuhe Shen
- School of Chemical Engineering and Technology, State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300072, P. R. China
| | - Jiayu Liu
- School of Chemical Engineering and Technology, State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300072, P. R. China
| | - Yuefei Wang
- School of Chemical Engineering and Technology, State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300072, P. R. China
- Tianjin Key Laboratory of Membrane Science and Desalination Technology, Tianjin University, Tianjin 300072, P. R. China
| | - Wei Qi
- School of Chemical Engineering and Technology, State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300072, P. R. China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, P. R. China
- Tianjin Key Laboratory of Membrane Science and Desalination Technology, Tianjin University, Tianjin 300072, P. R. China
| | - Rongxin Su
- School of Chemical Engineering and Technology, State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300072, P. R. China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, P. R. China
- Tianjin Key Laboratory of Membrane Science and Desalination Technology, Tianjin University, Tianjin 300072, P. R. China
| | - Zhimin He
- School of Chemical Engineering and Technology, State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300072, P. R. China
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Kowalska J, Rok J, Rzepka Z, Wrześniok D. Drug-Induced Photosensitivity-From Light and Chemistry to Biological Reactions and Clinical Symptoms. Pharmaceuticals (Basel) 2021; 14:723. [PMID: 34451820 PMCID: PMC8401619 DOI: 10.3390/ph14080723] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 07/23/2021] [Accepted: 07/24/2021] [Indexed: 02/07/2023] Open
Abstract
Photosensitivity is one of the most common cutaneous adverse drug reactions. There are two types of drug-induced photosensitivity: photoallergy and phototoxicity. Currently, the number of photosensitization cases is constantly increasing due to excessive exposure to sunlight, the aesthetic value of a tan, and the increasing number of photosensitizing substances in food, dietary supplements, and pharmaceutical and cosmetic products. The risk of photosensitivity reactions relates to several hundred externally and systemically administered drugs, including nonsteroidal anti-inflammatory, cardiovascular, psychotropic, antimicrobial, antihyperlipidemic, and antineoplastic drugs. Photosensitivity reactions often lead to hospitalization, additional treatment, medical management, decrease in patient's comfort, and the limitations of drug usage. Mechanisms of drug-induced photosensitivity are complex and are observed at a cellular, molecular, and biochemical level. Photoexcitation and photoconversion of drugs trigger multidirectional biological reactions, including oxidative stress, inflammation, and changes in melanin synthesis. These effects contribute to the appearance of the following symptoms: erythema, swelling, blisters, exudation, peeling, burning, itching, and hyperpigmentation of the skin. This article reviews in detail the chemical and biological basis of drug-induced photosensitivity. The following factors are considered: the chemical properties, the influence of individual ranges of sunlight, the presence of melanin biopolymers, and the defense mechanisms of particular types of tested cells.
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Affiliation(s)
| | | | | | - Dorota Wrześniok
- Department of Pharmaceutical Chemistry, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia in Katowice, Jagiellońska 4, 41-200 Sosnowiec, Poland; (J.K.); (J.R.); (Z.R.)
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Characterization of Temperature-Dependent Kinetics of Oculocutaneous Albinism-Causing Mutants of Tyrosinase. Int J Mol Sci 2021; 22:ijms22157771. [PMID: 34360537 PMCID: PMC8346126 DOI: 10.3390/ijms22157771] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/12/2021] [Accepted: 07/16/2021] [Indexed: 01/06/2023] Open
Abstract
Human tyrosinase (Tyr) is a glycoenzyme that catalyzes the first and rate-limiting step in melanin production, and its gene (TYR) is mutated in many cases of oculocutaneous albinism type 1 (OCA1). The mechanisms by which individual mutations contribute to the diverse pigmentation phenotype in patients with OCA1 have only began to be examined and remain to be delineated. Here, we analyze the temperature-dependent kinetics of wild-type Tyr (WT) and two OCA1B mutant variants (R422Q and P406L) using Michaelis–Menten and Van’t Hoff analyses. Recombinant truncated human Tyr proteins (residues 19–469) were produced in the whole insect Trichoplusia Ni larvae. Proteins were purified by a combination of affinity and size-exclusion chromatography. The temperature dependence of diphenol oxidase protein activities and kinetic parameters were measured by dopachrome absorption. Using the same experimental conditions, computational simulations were performed to assess the temperature-dependent association of L-DOPA and Tyr. Our results revealed, for the first time, that the association of L-DOPA with R422Q and P406L followed by dopachrome formation is a complex reaction supported by enthalpy and entropy forces. We show that the WT has a higher turnover number as compared with both R422Q and P406L. Elucidating the kinetics and thermodynamics of mutant variants of Tyr in OCA1B helps to understand the mechanisms by which they lower Tyr catalytic activity and to discover novel therapies for patients.
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