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Yazar C, Akbayrak A, Ozmen ZC, Kuyucu YE, Sencan M, Kutlu O, Seckin HY. Assessment of serum granulysin and cathepsin-L levels in vitiligo patients. REVISTA DA ASSOCIACAO MEDICA BRASILEIRA (1992) 2024; 70:e20231107. [PMID: 38775500 PMCID: PMC11111119 DOI: 10.1590/1806-9282.20231107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Accepted: 01/19/2024] [Indexed: 05/24/2024]
Abstract
OBJECTIVE Cellular and humoral immunity plays a role in the pathogenesis of vitiligo. T lymphocytes and natural killer cells involved in cellular immunity carry out their cytotoxic activities through perforin/granzyme-dependent granule exocytosis, in which granulysin and cathepsin-L are also involved. The aim of this study was to investigate the possible role of serum granulysin and cathepsin-L in the etiopathogenesis of vitiligo and their association with disease activity and severity. METHODS This randomized, prospective case-control study was conducted with 46 vitiligo patients admitted to the hospital for vitiligo between January and November 2021 and 46 healthy volunteers of similar age and gender. Serum levels of granulysin and cathepsin-L were measured by the enzyme-linked immunosorbent assay method. RESULTS The mean serum levels of granulysin and cathepsin-L were statistically significantly higher in vitiligo patients compared with the control group (p=0.048 and p=0.024, respectively). There was no statistically significant correlation between serum granulysin and serum cathepsin-L levels and disease severity in the patient group (r=0.30, p=0.062 and r=0.268, p=0.071, respectively). Disease activity also showed no significant association with serum granulysin and cathepsin-L levels (p=0.986 and p=0.962, respectively). CONCLUSION Although granulysin and cathepsin-L are molecules involved in the pathogenesis of vitiligo, the use of these molecules may not be helpful in assessing disease activity and severity. It may be helpful to conduct comprehensive and prospective studies to find new molecules to fill the gap in this area.
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Affiliation(s)
- Cemre Yazar
- Gaziosmanpasa University, School of Medicine, Department of Dermatology and Venereology – Tokat, Turkey
| | - Atiye Akbayrak
- Gaziosmanpasa University, School of Medicine, Department of Dermatology and Venereology – Tokat, Turkey
| | - Zeliha Cansel Ozmen
- Gaziosmanpasa University, School of Medicine, Department of Biochemistry – Tokat, Turkey
| | - Yunus Emre Kuyucu
- Gaziosmanpasa University, School of Medicine, Department of Biostatistics – Tokat, Turkey
| | | | - Omer Kutlu
- Gaziosmanpasa University, School of Medicine, Department of Dermatology and Venereology – Tokat, Turkey
| | - Havva Yildiz Seckin
- Gaziosmanpasa University, School of Medicine, Department of Dermatology and Venereology – Tokat, Turkey
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Bento-Lopes L, Cabaço LC, Charneca J, Neto MV, Seabra MC, Barral DC. Melanin's Journey from Melanocytes to Keratinocytes: Uncovering the Molecular Mechanisms of Melanin Transfer and Processing. Int J Mol Sci 2023; 24:11289. [PMID: 37511054 PMCID: PMC10379423 DOI: 10.3390/ijms241411289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 06/23/2023] [Accepted: 07/03/2023] [Indexed: 07/30/2023] Open
Abstract
Skin pigmentation ensures efficient photoprotection and relies on the pigment melanin, which is produced by epidermal melanocytes and transferred to surrounding keratinocytes. While the molecular mechanisms of melanin synthesis and transport in melanocytes are now well characterized, much less is known about melanin transfer and processing within keratinocytes. Over the past few decades, distinct models have been proposed to explain how melanin transfer occurs at the cellular and molecular levels. However, this remains a debated topic, as up to four different models have been proposed, with evidence presented supporting each. Here, we review the current knowledge on the regulation of melanin exocytosis, internalization, processing, and polarization. Regarding the different transfer models, we discuss how these might co-exist to regulate skin pigmentation under different conditions, i.e., constitutive and facultative skin pigmentation or physiological and pathological conditions. Moreover, we discuss recent evidence that sheds light on the regulation of melanin exocytosis by melanocytes and internalization by keratinocytes, as well as how melanin is stored within these cells in a compartment that we propose be named the melanokerasome. Finally, we review the state of the art on the molecular mechanisms that lead to melanokerasome positioning above the nuclei of keratinocytes, forming supranuclear caps that shield the nuclear DNA from UV radiation. Thus, we provide a comprehensive overview of the current knowledge on the molecular mechanisms regulating skin pigmentation, from melanin exocytosis by melanocytes and internalization by keratinocytes to processing and polarization within keratinocytes. A better knowledge of these molecular mechanisms will clarify long-lasting questions in the field that are crucial for the understanding of skin pigmentation and can shed light on fundamental aspects of organelle biology. Ultimately, this knowledge can lead to novel therapeutic strategies to treat hypo- or hyper-pigmentation disorders, which have a high socio-economic burden on patients and healthcare systems worldwide, as well as cosmetic applications.
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Affiliation(s)
| | | | | | | | | | - Duarte C. Barral
- iNOVA4Health, NOVA Medical School, Faculdade de Ciências Médicas, NMS, FCM, Universidade NOVA de Lisboa, 1169-056 Lisboa, Portugal; (L.B.-L.); (L.C.C.); (J.C.); (M.V.N.); (M.C.S.)
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3
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Lecaille F, Chazeirat T, Saidi A, Lalmanach G. Cathepsin V: Molecular characteristics and significance in health and disease. Mol Aspects Med 2022; 88:101086. [PMID: 35305807 DOI: 10.1016/j.mam.2022.101086] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 02/23/2022] [Accepted: 02/26/2022] [Indexed: 12/31/2022]
Abstract
Human cysteine cathepsins form a family of eleven proteases (B, C, F, H, K, L, O, S, V, W, X/Z) that play important roles in a considerable number of biological and pathophysiological processes. Among them, cathepsin V, also known as cathepsin L2, is a lysosomal enzyme, which is mainly expressed in cornea, thymus, heart, brain, and skin. Cathepsin V is a multifunctional endopeptidase that is involved in both the release of antigenic peptides and the maturation of MHC class II molecules and participates in the turnover of elastin fibrils as well in the cleavage of intra- and extra-cellular substrates. Moreover, there is increasing evidence that cathepsin V may contribute to the progression of diverse diseases, due to the dysregulation of its expression and/or its activity. For instance, increased expression of cathepsin V is closely correlated with malignancies (breast cancer, squamous cell carcinoma, or colorectal cancer) as well vascular disorders (atherosclerosis, aortic aneurysm, hypertension) being the most prominent examples. This review aims to shed light on current knowledge on molecular aspects of cathepsin V (genomic organization, protein structure, substrate specificity), its regulation by protein and non-protein inhibitors as well to summarize its expression (tissue and cellular distribution). Then the core biological and pathophysiological roles of cathepsin V will be depicted, raising the question of its interest as a valuable target that can open up pioneering therapeutic avenues.
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Affiliation(s)
- Fabien Lecaille
- Université de Tours, Tours, France; INSERM, UMR 1100, Centre d'Etude des Pathologies Respiratoires (CEPR), Team "Mécanismes protéolytiques dans l'inflammation", Tours, France.
| | - Thibault Chazeirat
- Université de Tours, Tours, France; INSERM, UMR 1100, Centre d'Etude des Pathologies Respiratoires (CEPR), Team "Mécanismes protéolytiques dans l'inflammation", Tours, France
| | - Ahlame Saidi
- Université de Tours, Tours, France; INSERM, UMR 1100, Centre d'Etude des Pathologies Respiratoires (CEPR), Team "Mécanismes protéolytiques dans l'inflammation", Tours, France
| | - Gilles Lalmanach
- Université de Tours, Tours, France; INSERM, UMR 1100, Centre d'Etude des Pathologies Respiratoires (CEPR), Team "Mécanismes protéolytiques dans l'inflammation", Tours, France.
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Xia Y, Ge M, Xia L, Shan G, Qian H. CTSV (cathepsin V) promotes bladder cancer progression by increasing NF-κB activity. Bioengineered 2022; 13:10180-10190. [PMID: 35443863 PMCID: PMC9162008 DOI: 10.1080/21655979.2022.2061278] [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] [Indexed: 12/24/2022] Open
Abstract
Chronic inflammation is positively associated with the development of urinary bladder cancer. However, its detailed regulatory mechanism remains elusive. The quantitative real-time polymerase chain reaction was used to measure mRNA levels of relative genes. The protein levels were monitored by western blotting. Cell proliferation and viability were evaluated by the cell counting Kit 8 (CCK8) and colony formation assays, respectively. The dual-luciferase reporter assay was performed to assay the transcriptional activity. In vivo experiments were implemented in nude mice as well. The TCGA database analysis suggested that the aberrant expression of cathepsin V (CTSV) was related to a poor outcome in bladder cancer patients. CTSV boosted the inflammation reaction, which facilitated the development of bladder cancer. The overexpression of CTSV increased the proliferation and viability of bladder cancer cells. On the contrary, the deletion of CTSV significantly inhibited the proliferation and viability of bladder cancer cells. The tumor repression resulting from CTSV deficiency in vitro was also verified in vivo. Moreover, multiple cancer-associated luciferase screening showed that the overexpression of CTSV triggered the inflammatory signaling pathway, which could be restored by introducing the NF-κB inhibitor. CTSV is upregulated and promotes proliferation through the NF-κB pathway in bladder cancer and may be a potential target in inflammation-associated bladder cancer.
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Affiliation(s)
- Yue Xia
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Minghuan Ge
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Ling Xia
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, China
| | - Guang Shan
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Huijun Qian
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
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Cathepsin L, a Target of Hypoxia-Inducible Factor-1-α, Is Involved in Melanosome Degradation in Melanocytes. Int J Mol Sci 2021; 22:ijms22168596. [PMID: 34445307 PMCID: PMC8395286 DOI: 10.3390/ijms22168596] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 07/31/2021] [Accepted: 08/09/2021] [Indexed: 01/07/2023] Open
Abstract
Hypoxic conditions induce the activation of hypoxia-inducible factor-1α (HIF-1α) to restore the supply of oxygen to tissues and cells. Activated HIF-1α translocates into the nucleus and binds to hypoxia response elements to promote the transcription of target genes. Cathepsin L (CTSL) is a lysosomal protease that degrades cellular proteins via the endolysosomal pathway. In this study, we attempted to determine if CTSL is a hypoxia responsive target gene of HIF-1α, and decipher its role in melanocytes in association with the autophagic pathway. The results of our luciferase reporter assay showed that the expression of CTSL is transcriptionally activated through the binding of HIF1-α at its promoter. Under autophagy-inducing starvation conditions, HIF-1α and CTSL expression is highly upregulated in melan-a cells. The mature form of CTSL is closely involved in melanosome degradation through lysosomal activity upon autophagosome–lysosome fusion. The inhibition of conversion of pro-CTSL to mature CTSL leads to the accumulation of gp100 and tyrosinase in addition to microtubule-associated protein 1 light chain 3 (LC3) II, due to decreased lysosomal activity in the autophagic pathway. In conclusion, we have identified that CTSL, a novel target of HIF-1α, participates in melanosome degradation in melanocytes through lysosomal activity during autophagosome–lysosome fusion.
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Zeng B, Li K, Yang Z, Wang H, Wang C, Huang P, Pan Y. Isoimperatorin (ISO) reduces melanin content in keratinocytes via miR-3619/CSTB and miR-3619/CSTD axes. Biosci Biotechnol Biochem 2020; 84:1436-1443. [PMID: 32299303 DOI: 10.1080/09168451.2020.1751581] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Melanin metabolism disorders may cause severe impacts on the psychological and social activities of patients. Different from the other two steps of melanin metabolism, namely synthesis and transport, little has been known about the mechanism of melanin degradation. Isoimperatorin (ISO) suppressed the activity of tyrosinase, an essential enzyme in melanin biosynthesis, hence, we investigated the effects and mechanism of ISO in melanin reduction. ISO stimulation significantly reduces the melanin contents and PMEL 17 protein levels; meanwhile, the activity and the protein levels of two critical lysosomal enzymes, Cathepsin B and Cathepsin D, can be significantly increased by ISO treatment. MiR-3619 inhibited the expression of CSTB and CSTD, therefore affecting ISO-induced degradation of melanin. In summary, ISO reduces the melanin content via miR-3619/CSTB and miR-3619/CSTD axes. ISO could be a potent skin-whitening agent, which needs further in vivo and clinical investigation.
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Affiliation(s)
- Bijun Zeng
- Department of Dermatology, the Second Affiliated Hospital, the Domestic First-class Discipline Construction Project of Chinese Medicine, Hunan University of Chinese Medicine , Changsha, Hunan, China
| | - Kai Li
- Department of Dermatology, the Second Affiliated Hospital, the Domestic First-class Discipline Construction Project of Chinese Medicine, Hunan University of Chinese Medicine , Changsha, Hunan, China
| | - Zhibo Yang
- Department of Dermatology, the Second Affiliated Hospital, the Domestic First-class Discipline Construction Project of Chinese Medicine, Hunan University of Chinese Medicine , Changsha, Hunan, China
| | - Haizhen Wang
- Department of Dermatology, the Second Affiliated Hospital, the Domestic First-class Discipline Construction Project of Chinese Medicine, Hunan University of Chinese Medicine , Changsha, Hunan, China
| | - Chang Wang
- Department of Dermatology, the Second Affiliated Hospital, the Domestic First-class Discipline Construction Project of Chinese Medicine, Hunan University of Chinese Medicine , Changsha, Hunan, China
| | - Pan Huang
- Department of Dermatology, the Second Affiliated Hospital, the Domestic First-class Discipline Construction Project of Chinese Medicine, Hunan University of Chinese Medicine , Changsha, Hunan, China
| | - Yi Pan
- Department of Dermatology, the Second Affiliated Hospital, the Domestic First-class Discipline Construction Project of Chinese Medicine, Hunan University of Chinese Medicine , Changsha, Hunan, China
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Endo K, Katsuyama Y, Taira N, Yoshioka M, Okano Y, Masaki H. Impairment of the autophagy system in repetitively UVA-irradiated fibroblasts. PHOTODERMATOLOGY PHOTOIMMUNOLOGY & PHOTOMEDICINE 2019; 36:111-117. [PMID: 31553079 DOI: 10.1111/phpp.12516] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 08/22/2019] [Accepted: 09/16/2019] [Indexed: 01/07/2023]
Abstract
BACKGROUND Autophagy is known as an intracellular cleanup system necessary to maintain homeostasis of the skin. Many studies have pointed out the relationship between aging and the inactivation of autophagy function, which suggests that the inactivation of autophagy occurs in aged skin. However, the aging process of the skin is complicated compared with other organs, because the skin is localized at the border between the inside of the body and the environment. Thus, skin aging is strongly affected by environmental factors, and it is well recognized that ultraviolet (UV) radiation is an important environmental factor that promotes skin aging. Therefore, characterizing the autophagic phenotypes induced by environmental factors is important to understand the process of skin aging. METHODS In order to demonstrate the status of autophagy during environment-induced aging of the skin, we investigated the autophagy profiles of normal human dermal fibroblasts (NHDFs) treated with repetitive UVA irradiation as model fibroblasts in photoaged skin. RESULTS Repetitively UVA-irradiated NHDFs showed increased numbers of autophagosomes, which coincided with the accumulation of p62 and increased levels of LAMP-1 and lysosomes. The behavior of repetitively UVA-irradiated NHDFs on autophagy was similar to that of NHDFs treated with hydroxychloroquine (HCQ), which is an inhibitor of lysosomal proteinase. CONCLUSION In summary, these results demonstrate that repetitively UVA-irradiated fibroblasts have reduced autophagy function due to the dysfunction of lysosomes.
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Affiliation(s)
- Karin Endo
- School of Bioscience and Biotechnology, Tokyo University of Technology, Hachiouji, Tokyo, Japan
| | | | | | | | - Yuri Okano
- School of Bioscience and Biotechnology, Tokyo University of Technology, Hachiouji, Tokyo, Japan
| | - Hitoshi Masaki
- School of Bioscience and Biotechnology, Tokyo University of Technology, Hachiouji, Tokyo, Japan
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8
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Del Bino S, Duval C, Bernerd F. Clinical and Biological Characterization of Skin Pigmentation Diversity and Its Consequences on UV Impact. Int J Mol Sci 2018; 19:ijms19092668. [PMID: 30205563 PMCID: PMC6163216 DOI: 10.3390/ijms19092668] [Citation(s) in RCA: 129] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 07/24/2018] [Accepted: 07/27/2018] [Indexed: 12/27/2022] Open
Abstract
Skin color diversity is the most variable and noticeable phenotypic trait in humans resulting from constitutive pigmentation variability. This paper will review the characterization of skin pigmentation diversity with a focus on the most recent data on the genetic basis of skin pigmentation, and the various methodologies for skin color assessment. Then, melanocyte activity and amount, type and distribution of melanins, which are the main drivers for skin pigmentation, are described. Paracrine regulators of melanocyte microenvironment are also discussed. Skin response to sun exposure is also highly dependent on color diversity. Thus, sensitivity to solar wavelengths is examined in terms of acute effects such as sunburn/erythema or induced-pigmentation but also long-term consequences such as skin cancers, photoageing and pigmentary disorders. More pronounced sun-sensitivity in lighter or darker skin types depending on the detrimental effects and involved wavelengths is reviewed.
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Affiliation(s)
- Sandra Del Bino
- L'Oréal Research and Innovation, 1 avenue Eugène Schueller, 93601 Aulnay-sous-Bois, France.
| | - Christine Duval
- L'Oréal Research and Innovation, 1 avenue Eugène Schueller, 93601 Aulnay-sous-Bois, France.
| | - Françoise Bernerd
- L'Oréal Research and Innovation, 1 avenue Eugène Schueller, 93601 Aulnay-sous-Bois, France.
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Homma T, Kageyama S, Nishikawa A, Nagata K. Melanosome degradation in epidermal keratinocytes related to lysosomal protease cathepsin V. Biochem Biophys Res Commun 2018; 500:339-343. [DOI: 10.1016/j.bbrc.2018.04.070] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 04/10/2018] [Indexed: 10/17/2022]
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10
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Yi WJ, Su MY, Shi Y, Jiang S, Xu SZ, Lei TC. Degraded melanocores are incompetent to protect epidermal keratinocytes against UV damage. Cell Cycle 2018; 17:844-857. [PMID: 29623762 DOI: 10.1080/15384101.2018.1456601] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Melanosomes are membrane-bound intracellular organelles that are uniquely generated by melanocytes (MCs) in the basal layer of human epidermis. Highly pigmented mature melanosomes are transferred from MCs to keratinocytes (KCs), and then positioned in the supra-nuclear region to ensure protection against ultraviolet radiation (UVR). However, the molecular mechanism underlying melanosome (or melanin pigment) transfer remains enigmatic. Emerging evidence shows that exo-/endo-cytosis of the melanosome core (termed melanocore) has been considered as the main transfer manner between MCs and KCs. As KCs in the skin migrate up from the basal layer and undergo terminal differentiation, the melanocores they have taken up from MCs are subjected to degradation. In this study, we isolated individual melanocores from human MCs in culture and then induced their destruction/disruption using a physical approach. The results demonstrate that the ultrastructural integrity of melanocores is essential for their antioxidant and photoprotective properties. In addition, we also show that cathepsin V (CTSV), a lysosomal acid protease, is involved in melanocore degradation in calcium-induced differentiated KCs and is also suppressed in KCs following exposure to UVA or UVB radiation. Thus, our study demonstrates that change in the proportion of melanocores in the intact/undegraded state by CTSV-related degradation in KCs affects photoprotection of the skin.
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Affiliation(s)
- Wen-Juan Yi
- a Department of Dermatology , Renmin Hospital of Wuhan University , Wuhan 430060 , China
| | - Meng-Yun Su
- a Department of Dermatology , Renmin Hospital of Wuhan University , Wuhan 430060 , China
| | - Ying Shi
- a Department of Dermatology , Renmin Hospital of Wuhan University , Wuhan 430060 , China
| | - Shan Jiang
- a Department of Dermatology , Renmin Hospital of Wuhan University , Wuhan 430060 , China
| | - Shi-Zheng Xu
- a Department of Dermatology , Renmin Hospital of Wuhan University , Wuhan 430060 , China
| | - Tie-Chi Lei
- a Department of Dermatology , Renmin Hospital of Wuhan University , Wuhan 430060 , China
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11
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Degradation of Tyrosinase by Melanosomal pH Change and a New Mechanism of Whitening with Propylparaben. COSMETICS 2017. [DOI: 10.3390/cosmetics4040043] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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12
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Hurbain I, Romao M, Sextius P, Bourreau E, Marchal C, Bernerd F, Duval C, Raposo G. Melanosome Distribution in Keratinocytes in Different Skin Types: Melanosome Clusters Are Not Degradative Organelles. J Invest Dermatol 2017; 138:647-656. [PMID: 29054596 DOI: 10.1016/j.jid.2017.09.039] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 09/11/2017] [Accepted: 09/23/2017] [Indexed: 10/18/2022]
Abstract
The melanosome pattern was characterized systematically in keratinocytes in situ in highly, moderately, and lightly pigmented human skin, classified according to the individual typological angle, a colorimetric measure of skin color phenotype. Electron microscopy of skin samples showed qualitatively and quantitatively that in highly pigmented skin, although melanosomes are mostly isolated and distributed throughout the entire epidermis, clusters are also observed in the basal layer. In moderately and lightly pigmented skin, melanosomes are concentrated in the first layer of the epidermis, isolated-but for most of them, grouped as clusters of melanocores delimited by a single membrane. Electron tomography resolving intracellular three-dimensional organization of organelles showed that clustered melanocores depict contacts with other cellular compartments, such as endoplasmic reticulum and mitochondria. Additionally, immunogold labelling showed that clusters of melanocores do not correspond to autophagosomes or melanophagosomes but that they present, similarly to melanosomes in melanocytes, features of nonacidic, nondegradative organelles. Overall, these observations suggest that melanocore clusters do not correspond to autophagic organelles but represent reservoirs or protective structures for melanosome integrity and function. These results open avenues for understanding the basis of skin pigmentation in different skin color phenotypes.
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Affiliation(s)
- Ilse Hurbain
- Institut Curie, Paris Sciences Lettres Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, Paris, France; Sorbonne Universités, Université Pierre et Marie Curie, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, Paris, France; Cell and Tissue Imaging Core Facility PICT-IBiSA, Institut Curie, Paris, France
| | - Maryse Romao
- Institut Curie, Paris Sciences Lettres Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, Paris, France; Sorbonne Universités, Université Pierre et Marie Curie, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, Paris, France; Cell and Tissue Imaging Core Facility PICT-IBiSA, Institut Curie, Paris, France
| | - Peggy Sextius
- L'Oréal Research and Innovation, Aulnay sous Bois, France
| | | | - Céline Marchal
- L'Oréal Research and Innovation, Aulnay sous Bois, France
| | | | | | - Graça Raposo
- Institut Curie, Paris Sciences Lettres Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, Paris, France; Sorbonne Universités, Université Pierre et Marie Curie, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, Paris, France.
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13
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Pribis JP, Al-Abed Y, Yang H, Gero D, Xu H, Montenegro MF, Bauer EM, Kim S, Chavan SS, Cai C, Li T, Szoleczky P, Szabo C, Tracey KJ, Billiar TR. The HIV Protease Inhibitor Saquinavir Inhibits HMGB1-Driven Inflammation by Targeting the Interaction of Cathepsin V with TLR4/MyD88. Mol Med 2015; 21:749-757. [PMID: 26349060 DOI: 10.2119/molmed.2015.00197] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 09/02/2015] [Indexed: 12/18/2022] Open
Abstract
Extracellular high-mobility group box 1 (HMGB1) (disulfide form), via activation of toll-like receptor 4 (TLR4)-dependent signaling, is a strong driver of pathologic inflammation in both acute and chronic conditions. Identification of selective inhibitors of HMGB1-TLR4 signaling could offer novel therapies that selectively target proximal endogenous activators of inflammation. A cell-based screening strategy led us to identify first generation HIV-protease inhibitors (PI) as potential inhibitors of HMGB1-TLR4 driven cytokine production. Here we report that the first-generation HIV-PI saquinavir (SQV), as well as a newly identified mammalian protease inhibitor STO33438 (334), potently block disulfide HMGB1-induced TLR4 activation, as assayed by the production of TNF-α by human monocyte-derived macrophages (THP-1). We further report on the identification of mammalian cathepsin V, a protease, as a novel target of these inhibitors. Cellular as well as recombinant protein studies show that the mechanism of action involves a direct interaction between cathepsin V with TLR4 and its adaptor protein MyD88. Treatment with SQV, 334 or the known cathepsin inhibitor SID26681509 (SID) significantly improved survival in murine models of sepsis and reduced liver damage following warm liver ischemia/reperfusion (I/R) models, both characterized by strong HMGB1-TLR4 driven pathology. The current study demonstrates a novel role for cathepsin V in TLR4 signaling and implicates cathepsin V as a novel target for first-generation HIV-PI compounds. The identification of cathepsin V as a target to block HMGB1-TLR4-driven inflammation could allow for a rapid transition of the discovery from the bench to the bedside. Disulfide HMGB1 drives pathologic inflammation in many models by activating signaling through TLR4. Cell-based screening identified the mammalian protease cathepsin V as a novel therapeutic target to inhibit TLR4-mediated inflammation induced by extracellular HMGB1 (disulfide form). We identified two protease inhibitors (PIs) that block cathepsin V and thereby inhibit disulfide HMGB1-induced TLR4 activation: saquinavir (SQV), a first-generation PI targeting viral HIV protease and STO33438 (334), targeting mammalian proteases. We discovered that cathepsin V binds TLR4 under basal and HMGB1-stimulated conditions, but dissociates in the presence of SQV over time. Thus cathepsin V is a novel target for first-generation HIV PIs and represents a potential therapeutic target of pathologic inflammation.
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Affiliation(s)
- John P Pribis
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America.,Integrative Molecular and Biomedical Sciences Graduate Program, Baylor College of Medicine, Houston, Texas, United States of America
| | - Yousef Al-Abed
- Laboratory of Biomedical Science, The Feinstein Institute for Medical Research, Manhasset, New York, United States of America.,Department of Medicinal Chemistry, The Feinstein Institute for Medical Research, Manhasset, New York, United States of America
| | - Huan Yang
- Laboratory of Biomedical Science, The Feinstein Institute for Medical Research, Manhasset, New York, United States of America
| | - Domokos Gero
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Hongbo Xu
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America.,The Third Xiangya Hospital, Central South University, Hunan, China
| | - Marcelo F Montenegro
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Eileen M Bauer
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Sodam Kim
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Sangeeta S Chavan
- Laboratory of Biomedical Science, The Feinstein Institute for Medical Research, Manhasset, New York, United States of America
| | - Changchun Cai
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Tunliang Li
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America.,The Third Xiangya Hospital, Central South University, Hunan, China
| | - Petra Szoleczky
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Csaba Szabo
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Kevin J Tracey
- Laboratory of Biomedical Science, The Feinstein Institute for Medical Research, Manhasset, New York, United States of America
| | - Timothy R Billiar
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
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14
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Quantitative changes in skin composition parameters due to chemotherapy in breast cancer patients: a cohort study. Breast Cancer Res Treat 2015. [DOI: 10.1007/s10549-015-3502-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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15
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Sage J, De Quéral D, Leblanc-Noblesse E, Kurfurst R, Schnebert S, Perrier E, Nizard C, Lalmanach G, Lecaille F. Differential expression of cathepsins K, S and V between young and aged Caucasian women skin epidermis. Matrix Biol 2014; 33:41-6. [PMID: 23871919 DOI: 10.1016/j.matbio.2013.07.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Revised: 07/08/2013] [Accepted: 07/09/2013] [Indexed: 10/26/2022]
Abstract
Cutaneous aging translates drastic structural and functional alterations in the extracellular matrix (ECM). Multiple mechanisms are involved, including changes in protease levels. We investigated the age-related protein expression and activity of cysteine cathepsins and the expression of two endogenous protein inhibitors in young and aged Caucasian women skin epidermis. Immunofluorescence studies indicate that the expression of cathepsins K, S and V, as well as cystatins A and M/E within keratinocytes is reduced in photoprotected skin of aged women. Furthermore, the overall endopeptidase activity of cysteine cathepsins in epidermis lysates decreased with age. Albeit dermal elastic fiber and laminin expression is reduced in aged skin, staining of nidogen-1, a key protein in BM assembly that is sensitive to proteolysis by cysteine, metallo- and serine proteases, has a similar pattern in both young and aged skin. Since cathepsins contribute to the hydrolysis and turnover of ECM/basement membrane components, the abnormal protein degradation and deposition during aging process may be related in part to a decline of lysosomal/endosomal cathepsin K, S and V activity.
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Affiliation(s)
- Juliette Sage
- INSERM, UMR 1100, Pathologies Respiratoires: protéolyse et aérosolthérapie, Centre d'Etude des Pathologies Respiratoires, Université François Rabelais, F-37032 Tours cedex, France; LVMH-Recherche, BP58, F-45800 Saint Jean de Braye, France
| | | | | | - Robin Kurfurst
- LVMH-Recherche, BP58, F-45800 Saint Jean de Braye, France
| | | | - Eric Perrier
- LVMH-Recherche, BP58, F-45800 Saint Jean de Braye, France
| | - Carine Nizard
- LVMH-Recherche, BP58, F-45800 Saint Jean de Braye, France
| | - Gilles Lalmanach
- INSERM, UMR 1100, Pathologies Respiratoires: protéolyse et aérosolthérapie, Centre d'Etude des Pathologies Respiratoires, Université François Rabelais, F-37032 Tours cedex, France
| | - Fabien Lecaille
- INSERM, UMR 1100, Pathologies Respiratoires: protéolyse et aérosolthérapie, Centre d'Etude des Pathologies Respiratoires, Université François Rabelais, F-37032 Tours cedex, France.
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16
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Hakozaki T, Laughlin T, Zhao S, Wang J, Deng D, Jewell-Motz E, Elstun L. A regulator of ubiquitin-proteasome activity, 2-hexyldecanol, suppresses melanin synthesis and the appearance of facial hyperpigmented spots. Br J Dermatol 2013; 169 Suppl 2:39-44. [DOI: 10.1111/bjd.12364] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/12/2013] [Indexed: 11/30/2022]
Affiliation(s)
- T. Hakozaki
- The Procter & Gamble Company; 8700 Mason Montgomery Road; Mason; OH; U.S.A
| | - T. Laughlin
- The Procter & Gamble Company; 8700 Mason Montgomery Road; Mason; OH; U.S.A
| | - S. Zhao
- The Procter & Gamble Company; 8700 Mason Montgomery Road; Mason; OH; U.S.A
| | - J. Wang
- The Procter & Gamble Company; 8700 Mason Montgomery Road; Mason; OH; U.S.A
| | - D. Deng
- P&G Technology Beijing Co., Ltd; No. 35 Yu'an Road B Zone; Shunyi District; Beijing; China
| | - E. Jewell-Motz
- The Procter & Gamble Company; 8700 Mason Montgomery Road; Mason; OH; U.S.A
| | - L. Elstun
- The Procter & Gamble Company; 8700 Mason Montgomery Road; Mason; OH; U.S.A
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17
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Ebanks JP, Koshoffer A, Wickett RR, Hakozaki T, Boissy RE. Hydrolytic enzymes of the interfollicular epidermis differ in expression and correlate with the phenotypic difference observed between light and dark skin. J Dermatol 2012; 40:27-33. [DOI: 10.1111/j.1346-8138.2012.01634.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Accepted: 05/08/2012] [Indexed: 11/30/2022]
Affiliation(s)
| | - Amy Koshoffer
- Department of Dermatology; University of Cincinnati; Cincinnati; Ohio; USA
| | | | | | - Raymond E. Boissy
- Department of Dermatology; University of Cincinnati; Cincinnati; Ohio; USA
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18
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Funkelstein L, Lu WD, Koch B, Mosier C, Toneff T, Taupenot L, O'Connor DT, Reinheckel T, Peters C, Hook V. Human cathepsin V protease participates in production of enkephalin and NPY neuropeptide neurotransmitters. J Biol Chem 2012; 287:15232-41. [PMID: 22393040 PMCID: PMC3346103 DOI: 10.1074/jbc.m111.310607] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 02/23/2012] [Indexed: 12/11/2022] Open
Abstract
Proteases are required for processing precursors into active neuropeptides that function as neurotransmitters for cell-cell communication. This study demonstrates the novel function of human cathepsin V protease for producing the neuropeptides enkephalin and neuropeptide Y (NPY). Cathepsin V is a human-specific cysteine protease gene. Findings here show that expression of cathepsin V in neuroendocrine PC12 cells and human neuronal SK-N-MC cells results in production of (Met)enkephalin from proenkephalin. Gene silencing of cathepsin V by siRNA in human SK-N-MC cells results in reduction of (Met)enkephalin by more than 80%, illustrating the prominent role of cathepsin V for neuropeptide production. In vitro processing of proenkephalin by cathepsin V occurs at dibasic residue sites to generate enkephalin-containing peptides and an ∼24-kDa intermediate present in human brain. Cathepsin V is present in human brain cortex and hippocampus where enkephalin and NPY are produced and is present in purified human neuropeptide secretory vesicles. Colocalization of cathepsin V with enkephalin and NPY in secretory vesicles of human neuroblastoma cells was illustrated by confocal microscopy. Furthermore, expression of cathepsin V with proNPY results in NPY production. These findings indicate the unique function of human cathepsin V for producing enkephalin and NPY neuropeptides required for neurotransmission in health and neurological diseases.
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Affiliation(s)
- Lydiane Funkelstein
- From the Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, California 92093
| | - W. Douglas Lu
- From the Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, California 92093
| | - Britta Koch
- the Institut für Molekulare Medizin und Zellforschung, Albert-Ludwigs Universitat, Freiburg, Germany D-79104 Freiburg
| | - Charles Mosier
- From the Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, California 92093
| | - Thomas Toneff
- From the Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, California 92093
| | - Laurent Taupenot
- the Department of Medicine, University of California, San Diego, California 92093
| | - Daniel T. O'Connor
- the Department of Medicine, University of California, San Diego, California 92093
| | - Thomas Reinheckel
- the Institut für Molekulare Medizin und Zellforschung, Albert-Ludwigs Universitat, Freiburg, Germany D-79104 Freiburg
- BIOSS Centre for Biological Signaling Studies, D-79104 Freiburg, Germany, and
| | - Christoph Peters
- the Institut für Molekulare Medizin und Zellforschung, Albert-Ludwigs Universitat, Freiburg, Germany D-79104 Freiburg
- BIOSS Centre for Biological Signaling Studies, D-79104 Freiburg, Germany, and
| | - Vivian Hook
- From the Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, California 92093
- the Department of Medicine, University of California, San Diego, California 92093
- the Departments of of Neurosciences, Pharmacology, and Medicine, University of California, San Diego, La Jolla, California 92093
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20
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Xiao K, Jehle F, Peters C, Reinheckel T, Schirmer RH, Dandekar T. CA/C1 peptidases of the malaria parasites Plasmodium falciparum and P. berghei and their mammalian hosts--a bioinformatical analysis. Biol Chem 2009; 390:1185-97. [PMID: 19663681 DOI: 10.1515/bc.2009.124] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In genome-wide screens we studied CA/C1 peptidases of malaria-causing plasmodia and their hosts (man and mouse). For Plasmodium falciparum and P. berghei, several new CA/C1 peptidase genes encoding proteases of the L- and B-family with specific promoter modules were identified. In addition, two new human CA/C1 peptidase loci and one new mouse gene locus were found; otherwise, the sets of CA/C1 peptidase genes in man and mouse seem to be complete now. In each species studied there is a multitude of CA/C1 peptidases with lysosomal localization signals and partial functional overlap according to similar but subfamily-specific structures. Individual target structures in plasmodia include residues specifically different in CA/C1 peptidase subsite 2. This is of medical interest considering CA/C1 peptidase inhibition for chemotherapy in malaria, malignancies and other diseases. Promoter structures and mRNA regulation differ widely among CA/C1 peptidase subfamilies and between mammals and plasmodia. We characterized promoter modules conserved in mouse and man for the CA/C1 peptidase families B and L (with the L-like subfamily, F-like subfamily and mouse-specific J-like subfamily). RNA motif searches revealed conserved regulatory elements such as GAIT elements; plasmodial CA/C1 peptidase mRNA elements include ARE elements and mammalian mRNAs contain 15-lox DICE elements.
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Affiliation(s)
- Ke Xiao
- Lehrstuhl für Bioinformatik, Universität Würzburg, Biozentrum, D-97074 Würzburg, Germany
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21
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Abstract
The genetic basis underlying normal variation in the pigmentary traits of skin, hair and eye colour has been the subject of intense research directed at understanding the diversity seen both between and within human populations. A combination of approaches have been used including comparative genomics of candidate genes and the identification of regions of the human genome under positive selection, together with genome-wide and specific allele association studies. Independent selection for different pigmentation gene sets has been found between Asian, European and African populations. Several genome-wide association studies for pigmentation have now been conducted and identified single nucleotide polymorphism (SNP) markers in known, TYR, TYRP1, OCA2, SLC45A2, SLC24A5, MC1R, ASIP, KITLG and previously unknown SLC24A4, IRF4, TPCN2, candidate genes. The contribution of SNP polymorphisms present in populations from South Asia have been tested and alleles found at TYR, SLC45A2 and SLC24A5 can largely account for differences between those of darkest and lightest skin reflectance using a simple additive model. Skin and hair colour associations in Europeans are found within a range of pigmentation gene alleles, whereas blue-brown eye colour can be explained by a single SNP proposed to regulate OCA2 expression. Functional testing of variant alleles has begun to connect phenotype correlations with biological differences. Variant MC1R alleles show direct correlations between the biochemical signalling properties of the encoded receptor and the red-hair fair skin pigmentation phenotype. Direct testing of a range of clonal melanocyte cultures derived from donor skin tissue characterized for three causal SNPs within SLC45A2, SLC24A5 and OCA2 has assessed their impact on melanin content and tyrosinase enzyme activity. From a culmination of genetic and functional studies, it is apparent that a number of genes impacting melanosome biogenesis or the melanin biosynthetic pathway are candidates to explain the diversity seen in human pigmentation.
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Affiliation(s)
- Richard A Sturm
- Melanogenix Group, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Qld, Australia.
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22
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Marín YE, Seiberg M, Lin CB. Aldo-keto reductase 1C subfamily genes in skin are UV-inducible: possible role in keratinocytes survival. Exp Dermatol 2009; 18:611-8. [PMID: 19320734 DOI: 10.1111/j.1600-0625.2008.00839.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Please cite this paper as: Aldo-keto reductase 1C subfamily genes in skin are UV-inducible: possible role in keratinocytes survival. Experimental Dermatology 2009; 18: 611-618.Abstract: Human skin is endowed with the capacity to synthesize and metabolize steroid hormones, a function of importance in skin physiology and pathology. It is the hormone-regulatory enzymes, including the aldo-keto reductase 1C subfamily (AKR1Cs) that are largely responsible for the local levels of active steroid hormones. AKR1C1 and AKR1C2 inactivate progesterone and 5alpha-dihydrotestosterone, respectively, whereas AKR1C3 activates oestradiol and testosterone. Here, we show that AKR1C1-3 are expressed in keratinocytes and fibroblasts, with marginal expression in melanocytes. In human primary keratinocytes, AKR1C1 and -2 were UVB-inducible in a dose-dependent manner, as shown by quantitative PCR and Western blot analyses. The induction of AKR1C1 by UVB was concomitant with the presence of an apoptotic marker, the cleavage product of poly-ADP ribose polymerase. Similarly, the activation of AKR1C1 and -2 upon UVB exposure was demonstrated in swine skin in vivo and in human skin explants. As expected, hydrogen peroxide-derived reactive oxygen species also induced AKR1C1 and -2 mRNA and protein levels in keratinocytes in a dose-dependent manner. Furthermore, down-regulation of AKR1Cs by small interfering ribonucleic acid led to significantly reduced cell viability. Based on the combined evidence of the presence of an apoptotic marker in the UVB-exposed keratinocytes with increased AKR1Cs expression and reduced cell viability in down-regulated AKR1Cs, we suggest that AKR1C subfamily genes are stress-inducible and might function as survival factors in keratinocytes.
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Affiliation(s)
- Yarí E Marín
- The Johnson & Johnson Skin Research Center, CPPW, a unit of Johnson & Johnson Consumer Companies Inc, Skillman, NJ 08558, USA
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23
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Gunathilake R, Schurer NY, Shoo BA, Celli A, Hachem JP, Crumrine D, Sirimanna G, Feingold KR, Mauro TM, Elias PM. pH-regulated mechanisms account for pigment-type differences in epidermal barrier function. J Invest Dermatol 2009; 129:1719-29. [PMID: 19177137 DOI: 10.1038/jid.2008.442] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
To determine whether pigment type determines differences in epidermal function, we studied stratum corneum (SC) pH, permeability barrier homeostasis, and SC integrity in three geographically disparate populations with pigment type I-II versus IV-V skin (Fitzpatrick I-VI scale). Type IV-V subjects showed: (i) lower surface pH (approximately 0.5 U); (ii) enhanced SC integrity (transepidermal water loss change with sequential tape strippings); and (iii) more rapid barrier recovery than type I-II subjects. Enhanced barrier function could be ascribed to increased epidermal lipid content, increased lamellar body production, and reduced acidity, leading to enhanced lipid processing. Compromised SC integrity in type I-II subjects could be ascribed to increased serine protease activity, resulting in accelerated desmoglein-1 (DSG-1)/corneodesmosome degradation. In contrast, DSG-1-positive CDs persisted in type IV-V subjects, but due to enhanced cathepsin-D activity, SC thickness did not increase. Adjustment of pH of type I-II SC to type IV-V levels improved epidermal function. Finally, dendrites from type IV-V melanocytes were more acidic than those from type I-II subjects, and they transfer more melanosomes to the SC, suggesting that melanosome secretion could contribute to the more acidic pH of type IV-V skin. These studies show marked pigment-type differences in epidermal structure and function that are pH driven.
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Affiliation(s)
- Roshan Gunathilake
- Department of Dermatology, Veteran Affairs Medical Center, University of California San Francisco, San Francisco, California 94121, USA.
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24
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Abstract
Hyperpigmentary problems, including postinflammatory hyperpigmentation, solar lentigos, and melasma, occur widely in the human population and are thus of broad interest for control. On the basis of genomic and proteomic understanding of the melanocyte and melanogenesis, there are potentially hundreds of proteins and other effectors involved in pigmentation. This knowledge, although complex, should prove most useful in identifying specific abnormalities that lead to the hyperpigmentary problems. Also available are new laboratory screening methods and skin color measurement tools that are increasing the pace at which materials can be screened and evaluated clinically for their effectiveness. Combined with a clear consumer need for effective pigmentation control agents, advanced pigmentary system understanding and new research capabilities are setting the stage for future technological advancements.
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