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Yasarbas SS, Inal E, Yildirim MA, Dubrac S, Lamartine J, Mese G. Connexins in epidermal health and diseases: insights into their mutations, implications, and therapeutic solutions. Front Physiol 2024; 15:1346971. [PMID: 38827992 PMCID: PMC11140265 DOI: 10.3389/fphys.2024.1346971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 04/15/2024] [Indexed: 06/05/2024] Open
Abstract
The epidermis, the outermost layer of the skin, serves as a protective barrier against external factors. Epidermal differentiation, a tightly regulated process essential for epidermal homeostasis, epidermal barrier formation and skin integrity maintenance, is orchestrated by several players, including signaling molecules, calcium gradient and junctional complexes such as gap junctions (GJs). GJ proteins, known as connexins facilitate cell-to-cell communication between adjacent keratinocytes. Connexins can function as either hemichannels or GJs, depending on their interaction with other connexons from neighboring keratinocytes. These channels enable the transport of metabolites, cAMP, microRNAs, and ions, including Ca2+, across cell membranes. At least ten distinct connexins are expressed within the epidermis and mutations in at least five of them has been linked to various skin disorders. Connexin mutations may cause aberrant channel activity by altering their synthesis, their gating properties, their intracellular trafficking, and the assembly of hemichannels and GJ channels. In addition to mutations, connexin expression is dysregulated in other skin conditions including psoriasis, chronic wound and skin cancers, indicating the crucial role of connexins in skin homeostasis. Current treatment options for conditions with mutant or altered connexins are limited and primarily focus on symptom management. Several therapeutics, including non-peptide chemicals, antibodies, mimetic peptides and allele-specific small interfering RNAs are promising in treating connexin-related skin disorders. Since connexins play crucial roles in maintaining epidermal homeostasis as shown with linkage to a range of skin disorders and cancer, further investigations are warranted to decipher the molecular and cellular alterations within cells due to mutations or altered expression, leading to abnormal proliferation and differentiation. This would also help characterize the roles of each isoform in skin homeostasis, in addition to the development of innovative therapeutic interventions. This review highlights the critical functions of connexins in the epidermis and the association between connexins and skin disorders, and discusses potential therapeutic options.
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Affiliation(s)
- S. Suheda Yasarbas
- Izmir Institute of Technology, Faculty of Science, Department of Molecular Biology and Genetics, Izmir, Turkiye
| | - Ece Inal
- Izmir Institute of Technology, Faculty of Science, Department of Molecular Biology and Genetics, Izmir, Turkiye
| | - M. Azra Yildirim
- Izmir Institute of Technology, Faculty of Science, Department of Molecular Biology and Genetics, Izmir, Turkiye
| | - Sandrine Dubrac
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Jérôme Lamartine
- Skin Functional Integrity Group, Laboratory for Tissue Biology and Therapeutics Engineering (LBTI) CNRS UMR5305, University of Lyon, Lyon, France
| | - Gulistan Mese
- Izmir Institute of Technology, Faculty of Science, Department of Molecular Biology and Genetics, Izmir, Turkiye
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Gopinath S, Sutaria N, Bordeaux ZA, Parthasarathy V, Deng J, Taylor MT, Marani M, Lee K, Pritchard T, Alajmi A, Adawi W, Oladipo OO, Semenov YR, Alphonse M, Kwatra SG. Reduced serum pyridoxine and 25-hydroxyvitamin D levels in adults with chronic pruritic dermatoses. Arch Dermatol Res 2023; 315:1771-1776. [PMID: 35534780 DOI: 10.1007/s00403-022-02357-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 03/29/2022] [Accepted: 04/19/2022] [Indexed: 12/01/2022]
Abstract
Little is known about the role nutritional factors play in the pathogenesis of chronic pruritic dermatoses (CPD). In this study, we analyzed nutritional deficiencies in CPD patients compared to matched controls. We conducted a population-based study from the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2006. The main outcomes of the study were laboratory data on serum vitamin levels in participants who answered affirmatively to the questionnaires on CPD as well as matched healthy controls. We identified 877 cases of CPD among 9817 adults in the US aged 20 to 59 years. These findings revealed a slightly higher percentage of females with CPD. Low vitamin B6 (OR 0.697; 95% CI: 0.696-0.699, p = 0.025) and vitamin D (OR 0.794; 95% CI: 0.789-0.799, p = 0.037) levels were associated with a higher rate of CPD compared to healthy controls. Our study suggests that low levels of Vitamin B6 and Vitamin D inversely correlates with the presence of CPD. These vitamin deficiencies suggest further studies on the effect of vitamin supplementation may help in patients with CPD.
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Affiliation(s)
- Shilpa Gopinath
- Department of Dermatology, CRB II, Johns Hopkins University School of Medicine, Suite 206, 1550 Orleans Street, Baltimore, MD, 21231, USA
| | - Nishadh Sutaria
- Department of Dermatology, CRB II, Johns Hopkins University School of Medicine, Suite 206, 1550 Orleans Street, Baltimore, MD, 21231, USA
| | - Zachary A Bordeaux
- Department of Dermatology, CRB II, Johns Hopkins University School of Medicine, Suite 206, 1550 Orleans Street, Baltimore, MD, 21231, USA
| | - Varsha Parthasarathy
- Department of Dermatology, CRB II, Johns Hopkins University School of Medicine, Suite 206, 1550 Orleans Street, Baltimore, MD, 21231, USA
| | - Junwen Deng
- Department of Dermatology, CRB II, Johns Hopkins University School of Medicine, Suite 206, 1550 Orleans Street, Baltimore, MD, 21231, USA
| | - Matthew T Taylor
- Department of Dermatology, CRB II, Johns Hopkins University School of Medicine, Suite 206, 1550 Orleans Street, Baltimore, MD, 21231, USA
| | - Melika Marani
- Department of Dermatology, CRB II, Johns Hopkins University School of Medicine, Suite 206, 1550 Orleans Street, Baltimore, MD, 21231, USA
| | - Kevin Lee
- Department of Dermatology, CRB II, Johns Hopkins University School of Medicine, Suite 206, 1550 Orleans Street, Baltimore, MD, 21231, USA
| | - Thomas Pritchard
- Department of Dermatology, CRB II, Johns Hopkins University School of Medicine, Suite 206, 1550 Orleans Street, Baltimore, MD, 21231, USA
| | - Ali Alajmi
- Department of Dermatology, CRB II, Johns Hopkins University School of Medicine, Suite 206, 1550 Orleans Street, Baltimore, MD, 21231, USA
| | - Waleed Adawi
- Department of Dermatology, CRB II, Johns Hopkins University School of Medicine, Suite 206, 1550 Orleans Street, Baltimore, MD, 21231, USA
| | - Olusola O Oladipo
- Department of Dermatology, CRB II, Johns Hopkins University School of Medicine, Suite 206, 1550 Orleans Street, Baltimore, MD, 21231, USA
| | - Yevgeniy R Semenov
- Department of Dermatology, Massachusetts General Hospital, Boston, MA, USA
| | - Martin Alphonse
- Department of Dermatology, CRB II, Johns Hopkins University School of Medicine, Suite 206, 1550 Orleans Street, Baltimore, MD, 21231, USA
| | - Shawn G Kwatra
- Department of Dermatology, CRB II, Johns Hopkins University School of Medicine, Suite 206, 1550 Orleans Street, Baltimore, MD, 21231, USA.
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Ramasubbu MK, Maji S, Padhan M, Maiti R, Hota D, Majumdar SKD, Srinivasan A. Chemotherapy-induced hand foot syndrome: comparative efficacy and safety of pharmacological prophylaxis - systematic review and Bayesian network meta-analysis. BMJ Support Palliat Care 2022:spcare-2022-004011. [PMID: 36564149 DOI: 10.1136/spcare-2022-004011] [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: 10/07/2022] [Accepted: 12/12/2022] [Indexed: 12/25/2022]
Abstract
BACKGROUND Hand-foot syndrome (HFS) is one of the most common toxicities experienced by patients receiving systemic chemotherapy agents such as capecitabine and multikinase inhibitors such as sorafenib. Several randomised controlled trials (RCTs) have investigated the efficacy and safety of prophylactic agents such as pyridoxine, celecoxib, urea cream and cystine/theanine in managing HFS. This network meta-analysis (NMA) evaluated data from high-quality trials to provide strong evidence in forming recommendations to prevent systemic cancer therapy-induced HFS. OBJECTIVE To examine the comparative efficacy and safety of interventions for preventing systemic chemotherapy-induced HFS in patients with cancer. METHODS We searched PubMed, Embase and clinical trial registry for RCTs of interventions for preventing HFS. Bayesian NMA was performed to estimate the OR with 95% credible intervals (CrI) from both direct and indirect evidence. The outcome measures were the incidence of HFS (grade ≥1) and moderate to severe HFS (grade ≥2). Adverse drug reactions were discussed descriptively. RESULTS A total of 15 RCTs with 2715 patients with 12 prophylactic strategies were included. The analysis showed only celecoxib could significantly prevent the incidence of moderate to severe HFS (grade ≥2) (OR 0.29, 95% CrI 0.13 to 0.68). But none of the preventive interventions could prevent the incidence of HFS (grade ≥1). CONCLUSION Only celecoxib (200 mg two times per day) showed significant prevention of the incidence of moderate to severe HFS. Pyridoxine (400 mg once daily) and urea cream (10%) have to be evaluated further in larger randomised trials.
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Affiliation(s)
- Mathan Kumar Ramasubbu
- Department of Pharmacology, All India Institute of Medical Sciences, Bhubaneswar, Orissa, India
| | - Shampa Maji
- Department of Pharmacology, All India Institute of Medical Sciences, Bhubaneswar, Orissa, India
| | - Milan Padhan
- Department of Pharmacology, All India Institute of Medical Sciences, Bhubaneswar, Orissa, India
| | - Rituparna Maiti
- Department of Pharmacology, All India Institute of Medical Sciences, Bhubaneswar, Orissa, India
| | - Debasish Hota
- Department of Pharmacology, All India Institute of Medical Sciences, Bhubaneswar, Orissa, India
| | - Saroj Kumar Das Majumdar
- Department of Radiation Oncology, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India
| | - Anand Srinivasan
- Department of Pharmacology, All India Institute of Medical Sciences, Bhubaneswar, Orissa, India
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Xiaozhe L, Meilan C, Beihui H, Junru L, Jingli G, Lifen K, Juan L. Pyridoxine Is Effective for Preventing Hand-Foot Syndrome Induced by Pegylated Liposomal Doxorubicin for Multiple Myeloma: The Results of a Randomized Study. Integr Cancer Ther 2022; 21:15347354221140402. [PMID: 36510385 PMCID: PMC9751154 DOI: 10.1177/15347354221140402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
PURPOSE Pegylated liposomal doxorubicin (PLD) is highly effective for treating multiple myeloma (MM). Hand-foot syndrome (HFS) is a dose-limiting adverse event of PLD that may reduce a patient's quality of life or prevent certain patients from receiving PLD. Several researchers have discovered that pyridoxine, an activated form of vitamin B6, may prevent PLD-associated HFS. We designed a prospective randomized trial to examine whether prophylactic pyridoxine might prevent the incidence or delay the occurrence of PLD-induced HFS in patients with MM. METHODS Patients who met the trial's eligibility requirements were randomized and then administered either pyridoxine 100 mg twice daily or no pyridoxine, in both cases accompanied by their PLD-containing chemotherapeutic agent. Follow-up of patients was performed until the completion of induction therapy, the development of HFS or disease progression. RESULTS Between January 1, 2017, and January 1, 2019, 105 patients were randomly assigned to the pyridoxine group (n = 52) or the no pyridoxine group (n = 53). In the pyridoxine and no pyridoxine groups, HFS developed after a median of 4 (range, 1-8 cycles) and 3 (range, 1-7 cycles) chemotherapeutic cycles, respectively. There were no grade 3 incidents recorded. Overall, 13.3% of patients experienced HFS. A 11 of 53 (20.8%) patients in the no pyridoxine group experienced HFS, compared to 3 of 52 (5.8%) patients in the pyridoxine group (P = .042); there was no difference in HFS grades (P = .725). CONCLUSIONS The findings of benefit from prophylactic pyridoxine in this open-label trial have suggested its promise as a treatment for reducing HFS in MM patients. Further research with a placebo-controlled design is recommended. CLINICAL TRIAL REGISTRATION ChiCTR2100050294.
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Affiliation(s)
- Li Xiaozhe
- The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Chen Meilan
- The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Huang Beihui
- The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Liu Junru
- The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Gu Jingli
- The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Kuang Lifen
- The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Li Juan
- The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China,Li Juan, Department of Hematology, The First Affiliated Hospital of Sun Yat-sen University, No. 58 Zhongshan Er Road, Guanghzou, Guangdong 510000, China.
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Kim N, Lee S, Lee S, Kang J, Choi Y, Park J, Park C, Khang D, Kim S. Portable Cold Atmospheric Plasma Patch-Mediated Skin Anti-Inflammatory Therapy. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2202800. [PMID: 36180414 PMCID: PMC9731685 DOI: 10.1002/advs.202202800] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 08/27/2022] [Indexed: 05/29/2023]
Abstract
Although plasma is a promising technology in various fields, its clinical application is restricted by several limitations. A cold atmospheric plasma (CAP) patch is fabricated to help overcome hurdles, especially when treating skin diseases. This patch has surface dielectric barrier discharge, which generates reactive oxygen species (ROS) and reactive nitrogen species (RNS) on a flexible polymer film surface on which the embedded electrode induces a locally strong electric field. The effect of the CAP patch on psoriasis is also evaluated. The distinct characteristics of psoriasis between the lesion and non-lesion area allow the CAP patch to be suitable for only lesion area for its treatment. The CAP patch induces the opening of calcium channels in keratinocytes, thereby restoring abnormal keratinocyte differentiation and the collapse of the tight junction; thus, alleviating psoriatic symptoms. In addition, the favorable effect is due to the induction of ROS/RNS by the CAP patch, not the electric field generated during plasma generation. The findings indicate that the proposed portable CAP patch can help treat inflammatory skin disorders, especially psoriasis. As this can be used easily as a combination therapy with existing drugs, it may help reduce side effects caused by existing drugs.
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Affiliation(s)
- Namkyung Kim
- Cell & Matrix Research InstituteDepartment of PharmacologySchool of MedicineKyungpook National UniversityDaegu41944South Korea
| | - Seunghun Lee
- Department of Nano‐Bio ConvergenceNano Surface Materials DivisionKorea Institute of Materials ScienceChangwon51508South Korea
| | - Soyoung Lee
- Immunoregulatory Materials Research CenterKorea Research Institute of Bioscience and BiotechnologyJeongeup56212South Korea
| | - Jinjoo Kang
- Cell & Matrix Research InstituteDepartment of PharmacologySchool of MedicineKyungpook National UniversityDaegu41944South Korea
| | - Young‐Ae Choi
- Cell & Matrix Research InstituteDepartment of PharmacologySchool of MedicineKyungpook National UniversityDaegu41944South Korea
| | - Jeongsu Park
- Department of PhysiologySchool of MedicineGachon UniversityIncheon21999South Korea
| | - Chul‐Kyu Park
- Department of PhysiologySchool of MedicineGachon UniversityIncheon21999South Korea
| | - Dongwoo Khang
- Department of PhysiologySchool of MedicineGachon UniversityIncheon21999South Korea
| | - Sang‐Hyun Kim
- Cell & Matrix Research InstituteDepartment of PharmacologySchool of MedicineKyungpook National UniversityDaegu41944South Korea
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Slominski AT, Slominski RM, Raman C, Chen JY, Athar M, Elmets C. Neuroendocrine signaling in the skin with a special focus on the epidermal neuropeptides. Am J Physiol Cell Physiol 2022; 323:C1757-C1776. [PMID: 36317800 PMCID: PMC9744652 DOI: 10.1152/ajpcell.00147.2022] [Citation(s) in RCA: 60] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 10/21/2022] [Accepted: 10/21/2022] [Indexed: 11/07/2022]
Abstract
The skin, which is comprised of the epidermis, dermis, and subcutaneous tissue, is the largest organ in the human body and it plays a crucial role in the regulation of the body's homeostasis. These functions are regulated by local neuroendocrine and immune systems with a plethora of signaling molecules produced by resident and immune cells. In addition, neurotransmitters, endocrine factors, neuropeptides, and cytokines released from nerve endings play a central role in the skin's responses to stress. These molecules act on the corresponding receptors in an intra-, juxta-, para-, or autocrine fashion. The epidermis as the outer most component of skin forms a barrier directly protecting against environmental stressors. This protection is assured by an intrinsic keratinocyte differentiation program, pigmentary system, and local nervous, immune, endocrine, and microbiome elements. These constituents communicate cross-functionally among themselves and with corresponding systems in the dermis and hypodermis to secure the basic epidermal functions to maintain local (skin) and global (systemic) homeostasis. The neurohormonal mediators and cytokines used in these communications regulate physiological skin functions separately or in concert. Disturbances in the functions in these systems lead to cutaneous pathology that includes inflammatory (i.e., psoriasis, allergic, or atopic dermatitis, etc.) and keratinocytic hyperproliferative disorders (i.e., seborrheic and solar keratoses), dysfunction of adnexal structure (i.e., hair follicles, eccrine, and sebaceous glands), hypersensitivity reactions, pigmentary disorders (vitiligo, melasma, and hypo- or hyperpigmentary responses), premature aging, and malignancies (melanoma and nonmelanoma skin cancers). These cellular, molecular, and neural components preserve skin integrity and protect against skin pathologies and can act as "messengers of the skin" to the central organs, all to preserve organismal survival.
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Affiliation(s)
- Andrzej T Slominski
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, Alabama
- Comprehensive Cancer Center, Cancer Chemoprevention Program, University of Alabama at Birmingham, Birmingham, Alabama
- VA Medical Center, Birmingham, Alabama
| | - Radomir M Slominski
- Graduate Biomedical Sciences Program, University of Alabama at Birmingham, Birmingham, Alabama
| | - Chander Raman
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Jake Y Chen
- Informatics Institute, University of Alabama at Birmingham, Birmingham, Alabama
| | - Mohammad Athar
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, Alabama
- VA Medical Center, Birmingham, Alabama
| | - Craig Elmets
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, Alabama
- Comprehensive Cancer Center, Cancer Chemoprevention Program, University of Alabama at Birmingham, Birmingham, Alabama
- VA Medical Center, Birmingham, Alabama
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Takeda M, Arai N, Koketsu Y, Mizoguchi Y. Factors associated with canine skin extensibility in toy poodles. J Vet Med Sci 2022; 84:282-288. [PMID: 35046238 PMCID: PMC8920729 DOI: 10.1292/jvms.21-0266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To assess factors for canine skin extensibility, our study investigated associations between the dogs' skin extension index and the following factors, gender, age, neuter status, weight, coat color and six coat color related gene polymorphisms. Swab samples were collected from 69 toy poodles to extract DNA. The skin extension indices of the lower back and the neck were measured using the following formula: vertical height of the skin fold divided by body length multiplied by 100. The dogs' age, weight, gender, neuter status and coat color were also recorded, as well as polymorphisms of the following six selected coat color related genes, Melanocortin 1 receptor, Tyrosinase-related protein 1, Melanophilin, Canine β-defensin-1, Major Facilitator Superfamily Domain Containing 12 and Agouti-signaling protein (ASIP). Univariable analysis showed there was a meaningful association between the lower back skin extension index and both gender and age (P<0.001 and P=0.048, respectively). Also, there was a possible association between the lower back skin extension index and ASIP Single nucleotide polymorphism (SNP) (R96C) (P=0.078). Linear model analysis showed there was a significant association between the lower back skin extension index and gender (P<0.001), and there was a tendency of the association between the lower back skin extension index and ASIP SNP (R96C) (P=0.098). In addition, there was an association between gender and age for the skin extension index. (P=0.048). Therefore, these results suggest that a greater risk of skin extensibility in toy poodle could be related to being female and the ASIP SNP (R96C), because these factors were associated with higher lower back skin extension index.
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Denda M, Nakanishi S. Do epidermal keratinocytes have sensory and information processing systems? Exp Dermatol 2021; 31:459-474. [PMID: 34726302 DOI: 10.1111/exd.14494] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 10/26/2021] [Accepted: 10/30/2021] [Indexed: 01/22/2023]
Abstract
It was long considered that the role of epidermal keratinocytes is solely to construct a water-impermeable protective membrane, the stratum corneum, at the uppermost layer of the skin. However, in the last two decades, it has been found that keratinocytes contain multiple sensory systems that detect environmental changes, including mechanical stimuli, sound, visible radiation, electric fields, magnetic fields, temperature and chemical stimuli, and also a variety of receptor molecules associated with olfactory or taste sensation. Moreover, neurotransmitters and their receptors that play crucial roles in the brain are functionally expressed in keratinocytes. Recent studies have demonstrated that excitation of keratinocytes can induce sensory perception in the brain. Here, we review the sensory and information processing capabilities of keratinocytes. We discuss the possibility that epidermal keratinocytes might represent the earliest stage in the development of the brain during the evolution of vertebrates.
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Affiliation(s)
- Mitsuhiro Denda
- Institute for Advanced Study of Mathematical Sciences, Meiji University, Nakano-ku, Tokyo, 164-8525, Japan
| | - Shinobu Nakanishi
- Shiseido Global Innovation Center, Nishi-ku, Yokohama, 220-0011, Japan
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O’Shaughnessy EM, Duffy W, Garcia-Vega L, Hussey K, Burden AD, Zamiri M, Martin PE. Dysregulation of Connexin Expression Plays a Pivotal Role in Psoriasis. Int J Mol Sci 2021; 22:ijms22116060. [PMID: 34199748 PMCID: PMC8200029 DOI: 10.3390/ijms22116060] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 05/28/2021] [Accepted: 06/01/2021] [Indexed: 12/13/2022] Open
Abstract
Background: Psoriasis, a chronic inflammatory disease affecting 2–3% of the population, is characterised by epidermal hyperplasia, a sustained pro-inflammatory immune response and is primarily a T-cell driven disease. Previous work determined that Connexin26 is upregulated in psoriatic tissue. This study extends these findings. Methods: Biopsies spanning psoriatic plaque (PP) and non-involved tissue (PN) were compared to normal controls (NN). RNA was isolated and subject to real-time PCR to determine gene expression profiles, including GJB2/CX26, GJB6/CX30 and GJA1/CX43. Protein expression was assessed by immunohistochemistry. Keratinocytes and fibroblasts were isolated and used in 3D organotypic models. The pro-inflammatory status of fibroblasts and 3D cultures was assessed via ELISA and RnD cytokine arrays in the presence or absence of the connexin channel blocker Gap27. Results: Connexin26 expression is dramatically enhanced at both transcriptional and translational level in PP and PN tissue compared to NN (>100x). In contrast, CX43 gene expression is not affected, but the protein is post-translationally modified and accumulates in psoriatic tissue. Fibroblasts isolated from psoriatic patients had a higher inflammatory index than normal fibroblasts and drove normal keratinocytes to adopt a “psoriatic phenotype” in a 3D-organotypic model. Exposure of normal fibroblasts to the pro-inflammatory mediator peptidoglycan, isolated from Staphylococcus aureus enhanced cytokine release, an event protected by Gap27. Conclusion: dysregulation of the connexin26:43 expression profile in psoriatic tissue contributes to an imbalance of cellular events. Inhibition of connexin signalling reduces pro-inflammatory events and may hold therapeutic benefit.
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Affiliation(s)
- Erin M. O’Shaughnessy
- Department of Biological and Biomedical Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, UK; (E.M.O.); (L.G.-V.)
| | - William Duffy
- Department of Dermatology, University Hospital Crosshouse, Kilmarnock KA2 0BE, UK; (W.D.); (M.Z.)
| | - Laura Garcia-Vega
- Department of Biological and Biomedical Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, UK; (E.M.O.); (L.G.-V.)
| | - Keith Hussey
- Department of Vascular Surgery, Queen Elizabeth University Hospital, Glasgow G51 4TF, UK;
| | - A. David Burden
- Institute of Infection Immunity and Inflammation, University of Glasgow, Glasgow G12 8TA, UK;
| | - Mozheh Zamiri
- Department of Dermatology, University Hospital Crosshouse, Kilmarnock KA2 0BE, UK; (W.D.); (M.Z.)
- Department of Dermatology, Queen Elizabeth University Hospital, Glasgow G51 4TF, UK
| | - Patricia E. Martin
- Department of Biological and Biomedical Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, UK; (E.M.O.); (L.G.-V.)
- Correspondence: ; Tel.: +44-141-331-3726
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A pilot randomized double-blind, placebo-controlled study on the effects of the topical application of pyridoxine on palmar-plantar erythrodysesthesia (PPE) induced by capecitabine or pegylated liposomal doxorubicin (PLD). Eur J Oncol Nurs 2021; 50:101866. [DOI: 10.1016/j.ejon.2020.101866] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 10/29/2020] [Accepted: 11/03/2020] [Indexed: 12/26/2022]
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Garcia-Vega L, O’Shaughnessy EM, Albuloushi A, Martin PE. Connexins and the Epithelial Tissue Barrier: A Focus on Connexin 26. BIOLOGY 2021; 10:biology10010059. [PMID: 33466954 PMCID: PMC7829877 DOI: 10.3390/biology10010059] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/11/2021] [Accepted: 01/12/2021] [Indexed: 12/15/2022]
Abstract
Simple Summary Tissues that face the external environment are known as ‘epithelial tissue’ and form barriers between different body compartments. This includes the outer layer of the skin, linings of the intestine and airways that project into the lumen connecting with the external environment, and the cornea of the eye. These tissues do not have a direct blood supply and are dependent on exchange of regulatory molecules between cells to ensure co-ordination of tissue events. Proteins known as connexins form channels linking cells directly and permit exchange of small regulatory signals. A range of environmental stimuli can dysregulate the level of connexin proteins and or protein function within the epithelia, leading to pathologies including non-healing wounds. Mutations in these proteins are linked with hearing loss, skin and eye disorders of differing severity. As such, connexins emerge as prime therapeutic targets with several agents currently in clinical trials. This review outlines the role of connexins in epithelial tissue and how their dysregulation contributes to pathological pathways. Abstract Epithelial tissue responds rapidly to environmental triggers and is constantly renewed. This tissue is also highly accessible for therapeutic targeting. This review highlights the role of connexin mediated communication in avascular epithelial tissue. These proteins form communication conduits with the extracellular space (hemichannels) and between neighboring cells (gap junctions). Regulated exchange of small metabolites less than 1kDa aide the co-ordination of cellular activities and in spatial communication compartments segregating tissue networks. Dysregulation of connexin expression and function has profound impact on physiological processes in epithelial tissue including wound healing. Connexin 26, one of the smallest connexins, is expressed in diverse epithelial tissue and mutations in this protein are associated with hearing loss, skin and eye conditions of differing severity. The functional consequences of dysregulated connexin activity is discussed and the development of connexin targeted therapeutic strategies highlighted.
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Denda M, Umino Y, Kumazawa N, Nakata S. Can simple physicochemical studies predict the effects of molecules on epidermal water‐impermeable barrier function? Exp Dermatol 2020; 29:393-399. [DOI: 10.1111/exd.14075] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Revised: 12/19/2019] [Accepted: 01/21/2020] [Indexed: 12/31/2022]
Affiliation(s)
| | - Yuki Umino
- Shiseido Global Innovation Center Yokohama Japan
| | - Noriyuki Kumazawa
- Department of Biomolecular Functional Engineering College of Engineering Ibaraki University Ibaraki Japan
| | - Satoshi Nakata
- Graduate School of Integrated Sciences for Life Hiroshima University Higashi‐Hiroshima Japan
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13
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Degovics D, Hartmann P, Németh IB, Árva-Nagy N, Kaszonyi E, Szél E, Strifler G, Bende B, Krenács L, Kemény L, Erős G. A novel target for the promotion of dermal wound healing: Ryanodine receptors. Toxicol Appl Pharmacol 2019; 366:17-24. [PMID: 30684528 DOI: 10.1016/j.taap.2019.01.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 01/11/2019] [Accepted: 01/23/2019] [Indexed: 10/27/2022]
Abstract
Ryanodine receptors have an important role in the regulation of intracellular calcium levels in the nervous system and muscle. It has been described that ryanodine receptors influence keratinocyte differentiation and barrier homeostasis. Our goal was to examine the role of ryanodine receptors in the healing of full-thickness dermal wounds by means of in vitro and in vivo methods. The effect of ryanodine receptors on wound healing, microcirculation and inflammation was assessed in an in vivo mouse wound healing model, using skin fold chambers in the dorsal region, and in HaCaT cell scratch wound assay in vitro. SKH-1 mice were subjected to sterile saline (n = 36) or ryanodine receptor agonist 4-chloro-m-cresol (0.5 mM) (n = 42) or ryanodine receptor antagonist dantrolene (100 μM) (n = 42). Application of ryanodine receptor agonist 4-chloro-m-cresol did not influence the studied parameters significantly, whereas ryanodine receptor antagonist dantrolene accelerated the wound closure. Inhibition of the calcium channel also increased the vessel diameters in the wound edges during the process of healing and increased the blood flow in the capillaries at all times of measurement. Furthermore, application of dantrolene decreased xanthine-oxidoreductase activity during the inflammatory phase of wound healing. Inhibition of ryanodine receptor-mediated effects positively influence wound healing. Thus, dantrolene may be of therapeutic potential in the treatment of wounds.
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Affiliation(s)
- Döníz Degovics
- Department of Dermatology and Allergology, University of Szeged, Szeged, Hungary.
| | - Petra Hartmann
- Institute of Surgical Research, University of Szeged, Szeged, Hungary
| | - István Balázs Németh
- Department of Dermatology and Allergology, University of Szeged, Szeged, Hungary
| | - Noémi Árva-Nagy
- Department of Dermatology and Allergology, University of Szeged, Szeged, Hungary
| | - Enikő Kaszonyi
- Department of Dermatology and Allergology, University of Szeged, Szeged, Hungary
| | - Edit Szél
- Department of Dermatology and Allergology, University of Szeged, Szeged, Hungary
| | - Gerda Strifler
- Institute of Surgical Research, University of Szeged, Szeged, Hungary
| | - Balázs Bende
- Department of Dermatology and Allergology, University of Szeged, Szeged, Hungary
| | - László Krenács
- Laboratory of Tumour Pathology and Molecular Diagnostics, Szeged, Hungary
| | - Lajos Kemény
- Department of Dermatology and Allergology, University of Szeged, Szeged, Hungary; MTA-SZTE Dermatological Research Group, Szeged, Hungary
| | - Gábor Erős
- Department of Dermatology and Allergology, University of Szeged, Szeged, Hungary
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Extracellular ATP activates hyaluronan synthase 2 ( HAS2) in epidermal keratinocytes via P2Y 2, Ca 2+ signaling, and MAPK pathways. Biochem J 2018; 475:1755-1772. [PMID: 29626161 DOI: 10.1042/bcj20180054] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 03/28/2018] [Accepted: 04/06/2018] [Indexed: 01/04/2023]
Abstract
Extracellular nucleotides are used as signaling molecules by several cell types. In epidermis, their release is triggered by insults such as ultraviolet radiation, barrier disruption, and tissue wounding, and by specific nerve terminals firing. Increased synthesis of hyaluronan, a ubiquitous extracellular matrix glycosaminoglycan, also occurs in response to stress, leading to the attractive hypothesis that nucleotide signaling and hyaluronan synthesis could also be linked. In HaCaT keratinocytes, ATP caused a rapid and strong but transient activation of hyaluronan synthase 2 (HAS2) expression via protein kinase C-, Ca2+/calmodulin-dependent protein kinase II-, mitogen-activated protein kinase-, and calcium response element-binding protein-dependent pathways by activating the purinergic P2Y2 receptor. Smaller but more persistent up-regulation of HAS3 and CD44, and delayed up-regulation of HAS1 were also observed. Accumulation of peri- and extracellular hyaluronan followed 4-6 h after stimulation, an effect further enhanced by the hyaluronan precursor glucosamine. AMP and adenosine, the degradation products of ATP, markedly inhibited HAS2 expression and, despite concomitant up-regulation of HAS1 and HAS3, inhibited hyaluronan synthesis. Functionally, ATP moderately increased cell migration, whereas AMP and adenosine had no effect. Our data highlight the strong influence of adenosinergic signaling on hyaluronan metabolism in human keratinocytes. Epidermal insults are associated with extracellular ATP release, as well as rapid up-regulation of HAS2/3, CD44, and hyaluronan synthesis, and we show here that the two phenomena are linked. Furthermore, as ATP is rapidly degraded, the opposite effects of its less phosphorylated derivatives facilitate a rapid shut-off of the hyaluronan response, providing a feedback mechanism to prevent excessive reactions when more persistent signals are absent.
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15
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Chanson M, Watanabe M, O'Shaughnessy EM, Zoso A, Martin PE. Connexin Communication Compartments and Wound Repair in Epithelial Tissue. Int J Mol Sci 2018; 19:ijms19051354. [PMID: 29751558 PMCID: PMC5983803 DOI: 10.3390/ijms19051354] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 04/26/2018] [Accepted: 04/26/2018] [Indexed: 12/20/2022] Open
Abstract
Epithelial tissues line the lumen of tracts and ducts connecting to the external environment. They are critical in forming an interface between the internal and external environment and, following assault from environmental factors and pathogens, they must rapidly repair to maintain cellular homeostasis. These tissue networks, that range from a single cell layer, such as in airway epithelium, to highly stratified and differentiated epithelial surfaces, such as the epidermis, are held together by a junctional nexus of proteins including adherens, tight and gap junctions, often forming unique and localised communication compartments activated for localised tissue repair. This review focuses on the dynamic changes that occur in connexins, the constituent proteins of the intercellular gap junction channel, during wound-healing processes and in localised inflammation, with an emphasis on the lung and skin. Current developments in targeting connexins as corrective therapies to improve wound closure and resolve localised inflammation are also discussed. Finally, we consider the emergence of the zebrafish as a concerted whole-animal model to study, visualise and track the events of wound repair and regeneration in real-time living model systems.
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Affiliation(s)
- Marc Chanson
- Department of Pediatrics and Cell Physiology & Metabolism, Geneva University Hospitals and University of Geneva, 1211 Geneva, Switzerland.
| | - Masakatsu Watanabe
- Graduate School of Frontier Biosciences, Osaka University, Osaka 565-0871, Japan.
| | - Erin M O'Shaughnessy
- Department of Life Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, UK.
| | - Alice Zoso
- Department of Pediatrics and Cell Physiology & Metabolism, Geneva University Hospitals and University of Geneva, 1211 Geneva, Switzerland.
| | - Patricia E Martin
- Department of Life Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, UK.
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16
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Nikolaou V, Syrigos K, Saif MW. Incidence and implications of chemotherapy related hand-foot syndrome. Expert Opin Drug Saf 2016; 15:1625-1633. [PMID: 27718746 DOI: 10.1080/14740338.2016.1238067] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
INTRODUCTION Hand-foot syndrome (HFS) is a well-established cutaneous adverse event of certain chemotherapeutic agents, mainly capecitabine, continuously infused 5-fluorouracil, docetaxel and pegylated liposomal doxorubicin. Erythema, dysesthesia, pain, cracking and desquamation located on palms and soles are the most characteristic manifestations. Although HFS is a reversible and non-life-threatening clinical condition, it can often affect patient's quality of life significantly, hence necessitating therapeutic modifications or even treatment discontinuation. Areas covered: This is review article on current data regarding the clinical characteristics, grading and management of HFS. Special focus has been given to recent literature studying novel therapeutic strategies. Expert opinion: Early recognition, patient education and supportive measures are considered as the key elements in the management of HFS. Up to date, treatment interruption and dose intensity reduction are the mainstay of HFS management. Many topical formulations and systemic treatment regimens have been proposed, with COX-2 inhibitors being the most promising agents. Nevertheless, large prospective randomized controlled trials are needed in order to agree on solid, evidence-based treatment algorithms.
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Affiliation(s)
- V Nikolaou
- a Oncology Unit, Third Department of Medicine , Athens Medical School, Sotiria General Hospital , Athens , Greece
| | - K Syrigos
- a Oncology Unit, Third Department of Medicine , Athens Medical School, Sotiria General Hospital , Athens , Greece
| | - M W Saif
- b GI Oncology Experimental Therapeutic , Tufts Medical Center, Tufts Cancer Center , Boston , MA , USA
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17
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Denda M. Keratinocytes at the uppermost layer of epidermis might act as sensors of atmospheric pressure change. EXTREME PHYSIOLOGY & MEDICINE 2016; 5:11. [PMID: 27761235 PMCID: PMC5054589 DOI: 10.1186/s13728-016-0052-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 09/30/2016] [Indexed: 11/10/2022]
Abstract
It has long been suggested that climate, especially atmospheric pressure change, can cause health problems ranging from migraine to myocardial infarction. Here, I hypothesize that the sensory system of epidermal keratinocytes mediates the influence of atmospheric pressure change on the human physiological condition. We previously demonstrated that even subtle changes of atmospheric pressure (5–20 hPa) induce elevation of intracellular calcium level in cultured human keratinocytes (excitation of keratinocytes). It is also established that communication occurs between epidermal keratinocytes and peripheral nerve systems. Moreover, various neurotransmitters and hormones that influence multiple systems (nervous, cardiovascular, endocrine, and immune systems) are generated and released from epidermal keratinocytes in response to various external stimuli. Thus, I suggest that pathophysiological phenomena induced by atmospheric pressure changes might be triggered by epidermal keratinocytes.
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Affiliation(s)
- Mitsuhiro Denda
- Shiseido Global Innovation Center, 2-2-1, Hayabuchi, Tsuzuki-ku, Yokohama, 224-8558 Japan ; Japan Science Technology Agency CREST, Kawaguchi, Japan
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18
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Abstract
Background: The nucleotide adenosine triphosphate (ATP) has long been known to drive and participate in countless intracellular processes. Extracellular ATP and its metabolite adenosine have also been shown to exert a variety of effects on nearly every cell type in human skin. Knowledge of the sources and effects of extracellular ATP in human skin may help shape new therapies for skin injury, inflammation, and numerous other cutaneous disorders. Objective: The objective of this review is to introduce the reader to current knowledge regarding the sources and effects of extracellular ATP in human skin and to outline areas in which further research is necessary to clarify the nature and mechanism of these effects. Conclusion: Extracellular ATP seems to play a direct role in triggering skin inflammatory, regenerative, and fibrotic responses to mechanical injury, an indirect role in melanocyte proliferation and apoptosis, and a complex role in Langerhans cell-directed adaptive immunity.
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Affiliation(s)
| | - Richard D. Granstein
- Department of Dermatology, Joan and Sanford I. Weill Medical College of Cornell University, New York, New York, USA
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19
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Riding A, Pullar CE. ATP Release and P2 Y Receptor Signaling are Essential for Keratinocyte Galvanotaxis. J Cell Physiol 2016; 231:181-91. [PMID: 26058714 DOI: 10.1002/jcp.25070] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Accepted: 06/05/2015] [Indexed: 01/06/2023]
Abstract
Repair to damaged tissue requires directional cell migration to heal the wound. Immediately upon wounding an electrical guidance cue is created with the cathode of the electric field (EF) located at the center of the wound. Previous research has demonstrated directional migration of keratinocytes toward the cathode when an EF of physiological strength (100-150 mV/mm) is applied in vitro, but the "sensor" by which keratinocytes sense the EF remains elusive. Here we use a customized chamber design to facilitate the application of a direct current (DC) EF of physiological strength (100 mV/mm) to keratinocytes whilst pharmacologically modulating the activation of both connexin hemichannels and purinergic receptors to determine their role in EF-mediated directional keratinocyte migration, galvanotaxis. In addition, keratinocytes were exposed to DiSCAC2 (3) dye to visualize membrane potential changes within the cell upon exposure to the applied DC EF. Here we unveil ATP-medicated mechanisms that underpin the initiation of keratinocyte galvanotaxis. The application of a DC EF of 100 mV/mm releases ATP via hemichannels activating a subset of purinergic P2 Y receptors, locally, to initiate the directional migration of keratinocytes toward the cathode in vitro, the center of the wound in vivo. The delineation of the mechanisms underpinning galvanotaxis extends our understanding of this endogenous cue and will facilitate the optimization and wider use of EF devices for chronic wound treatment. J. Cell. Physiol. 230: 181-191, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Aimie Riding
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, UK
| | - Christine E Pullar
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, UK
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20
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García IE, Bosen F, Mujica P, Pupo A, Flores-Muñoz C, Jara O, González C, Willecke K, Martínez AD. From Hyperactive Connexin26 Hemichannels to Impairments in Epidermal Calcium Gradient and Permeability Barrier in the Keratitis-Ichthyosis-Deafness Syndrome. J Invest Dermatol 2016; 136:574-583. [PMID: 26777423 DOI: 10.1016/j.jid.2015.11.017] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 11/05/2015] [Accepted: 11/06/2015] [Indexed: 01/19/2023]
Abstract
The keratitis-ichthyosis-deafness (KID) syndrome is characterized by corneal, skin, and hearing abnormalities. KID has been linked to heterozygous dominant missense mutations in the GJB2 and GJB6 genes, encoding connexin26 and 30, respectively. In vitro evidence indicates that KID mutations lead to hyperactive (open) hemichannels, which in some cases is accompanied by abnormal function of gap junction channels. Transgenic mouse models expressing connexin26 KID mutations reproduce human phenotypes and present impaired epidermal calcium homeostasis and abnormal lipid composition of the stratum corneum affecting the water barrier. Here we have compiled relevant data regarding the KID syndrome and propose a mechanism for the epidermal aspects of the disease.
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Affiliation(s)
- Isaac E García
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Felicitas Bosen
- LIMES (Life and Medical Sciences) Institute, University of Bonn, Bonn, Germany
| | - Paula Mujica
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Amaury Pupo
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Carolina Flores-Muñoz
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Oscar Jara
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Carlos González
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Klaus Willecke
- LIMES (Life and Medical Sciences) Institute, University of Bonn, Bonn, Germany.
| | - Agustín D Martínez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile.
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21
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Keratitis-ichthyosis-deafness syndrome-associated Cx26 mutants produce nonfunctional gap junctions but hyperactive hemichannels when co-expressed with wild type Cx43. J Invest Dermatol 2015; 135:1338-1347. [PMID: 25625422 PMCID: PMC4801018 DOI: 10.1038/jid.2015.20] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 01/13/2015] [Accepted: 01/14/2015] [Indexed: 11/09/2022]
Abstract
Mutations in Cx26 gene are found in most cases of human genetic deafness. Some mutations produce syndromic deafness associated with skin disorders, like the Keratitis-Ichthyosis-Deafness syndrome (KID). Because in the human skin connexin 26 (Cx26) is co-expressed with other connexins, like Cx43 and Cx30, and as the KID syndrome is inherited as autosomal dominant condition, it is possible that KID mutations change the way Cx26 interacts with other co-expressed connexins. Indeed, some Cx26 syndromic mutations showed gap junction dominant negative effect when co-expressed with wild-type connexins, including Cx26 and Cx43. The nature of these interactions and the consequences on hemichannels and gap junction channel (GJC) functions remain unknown. In this study, we demonstrate that syndromic mutations, at the N terminus segment of Cx26, change connexin oligomerization compatibility, allowing aberrant interactions with Cx43. Strikingly, heteromeric oligomer formed by Cx43/Cx26 (syndromic mutants) shows exacerbated hemichannel activity but nonfunctional GJCs; this also occurs for those Cx26 KID mutants that do not show functional homomeric hemichannels. Heterologous expression of these hyperactive heteromeric hemichannels increases cell membrane permeability, favoring ATP release and Ca(2+) overload. The functional paradox produced by oligomerization of Cx43 and Cx26 KID mutants could underlie the severe syndromic phenotype in human skin.
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22
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Denda M, Denda S, Tsutsumi M, Goto M, Kumamoto J, Nakatani M, Takei K, Kitahata H, Nakata S, Sawabu Y, Kobayashi Y, Nagayama M. Frontiers in epidermal barrier homeostasis--an approach to mathematical modelling of epidermal calcium dynamics. Exp Dermatol 2014; 23:79-82. [PMID: 24330223 DOI: 10.1111/exd.12302] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/05/2013] [Indexed: 01/04/2023]
Abstract
Intact epidermal barrier function is crucial for survival and is associated with the presence of gradients of both calcium ion concentration and electric potential. Although many molecules, including ion channels and pumps, are known to contribute to maintenance of these gradients, the mechanisms involved in epidermal calcium ion dynamics have not been clarified. We have established that a variety of neurotransmitters and their receptors, originally found in the brain, are expressed in keratinocytes and are also associated with barrier homeostasis. Moreover, keratinocytes and neurons show some similarities of electrochemical behaviour. As mathematical modelling and computer simulation have been employed to understand electrochemical phenomena in brain science, we considered that a similar approach might be applicable to describe the dynamics of epidermal electrochemical phenomena associated with barrier homeostasis. Such methodology would also be potentially useful to address a number of difficult problems in clinical dermatology, such as ageing and itching. Although this work is at a very early stage, in this essay, we discuss the background to our approach and we present some preliminary results of simulation of barrier recovery.
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Affiliation(s)
- Mitsuhiro Denda
- Japan Science and Technology Agency, CREST, Tokyo, Japan; Shiseido Research Center, Yokohama, Japan
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23
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Busse D, Kudella P, Grüning NM, Gisselmann G, Ständer S, Luger T, Jacobsen F, Steinsträßer L, Paus R, Gkogkolou P, Böhm M, Hatt H, Benecke H. A synthetic sandalwood odorant induces wound-healing processes in human keratinocytes via the olfactory receptor OR2AT4. J Invest Dermatol 2014; 134:2823-2832. [PMID: 24999593 DOI: 10.1038/jid.2014.273] [Citation(s) in RCA: 151] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 02/19/2014] [Accepted: 03/05/2014] [Indexed: 12/23/2022]
Abstract
As the outermost barrier of the body, the skin is exposed to multiple environmental factors, including temperature, humidity, mechanical stress, and chemical stimuli such as odorants that are often used in cosmetic articles. Keratinocytes, the major cell type of the epidermal layer, express a variety of different sensory receptors that enable them to react to various environmental stimuli and process information in the skin. Here we report the identification of a novel type of chemoreceptors in human keratinocytes, the olfactory receptors (ORs). We cloned and functionally expressed the cutaneous OR, OR2AT4, and identified Sandalore, a synthetic sandalwood odorant, as an agonist of this receptor. Sandalore induces strong Ca(2+) signals in cultured human keratinocytes, which are mediated by OR2AT4, as demonstrated by receptor knockdown experiments using RNA interference. The activation of OR2AT4 induces a cAMP-dependent pathway and phosphorylation of extracellular signal-regulated kinases (Erk1/2) and p38 mitogen-activated protein kinases (p38 MAPK). Moreover, the long-term stimulation of keratinocytes with Sandalore positively affected cell proliferation and migration, and regeneration of keratinocyte monolayers in an in vitro wound scratch assay. These findings combined with our studies on human skin organ cultures strongly indicate that the OR 2AT4 is involved in human keratinocyte re-epithelialization during wound-healing processes.
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Affiliation(s)
- Daniela Busse
- Department of Cellphysiology, Ruhr-University Bochum, Bochum, Germany
| | - Philipp Kudella
- Department of Cellphysiology, Ruhr-University Bochum, Bochum, Germany
| | | | - Günter Gisselmann
- Department of Cellphysiology, Ruhr-University Bochum, Bochum, Germany
| | - Sonja Ständer
- Department of Dermatology, Competence Centre Chronic Pruritus, University Hospital Münster, Münster, Germany
| | | | - Frank Jacobsen
- Department of Plastic Surgery, BG University Hospital Bergmannsheil, Ruhr-University Bochum, Bochum, Germany
| | - Lars Steinsträßer
- Department of Plastic Surgery, BG University Hospital Bergmannsheil, Ruhr-University Bochum, Bochum, Germany
| | - Ralf Paus
- Institute of Inflammation and Repair, University of Manchester, Manchester, UK
| | - Paraskevi Gkogkolou
- Laboratory for Neuroendocrinology of the Skin and Interdisciplinary Endocrinology, Department of Dermatology, University Hospital Münster, Münster, Germany
| | - Markus Böhm
- Laboratory for Neuroendocrinology of the Skin and Interdisciplinary Endocrinology, Department of Dermatology, University Hospital Münster, Münster, Germany
| | - Hanns Hatt
- Department of Cellphysiology, Ruhr-University Bochum, Bochum, Germany.
| | - Heike Benecke
- Department of Cellphysiology, Ruhr-University Bochum, Bochum, Germany
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24
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Burnstock G. Introduction and perspective, historical note. Front Cell Neurosci 2013; 7:227. [PMID: 24312014 PMCID: PMC3836022 DOI: 10.3389/fncel.2013.00227] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Accepted: 11/04/2013] [Indexed: 12/11/2022] Open
Abstract
P2 nucleotide receptors were proposed to consist of two subfamilies based on pharmacology in 1985, named P2X and P2Y receptors. Later, this was confirmed following cloning of the receptors for nucleotides and studies of transduction mechanisms in the early 1990s. P2X receptors are ion channels and seven subtypes are recognized that form trimeric homomultimers or heteromultimers. P2X receptors are involved in neuromuscular and synaptic neurotransmission and neuromodulation. They are also expressed on many types of non-neuronal cells to mediate smooth muscle contraction, secretion, and immune modulation. The emphasis in this review will be on the pathophysiology of P2X receptors and therapeutic potential of P2X receptor agonists and antagonists for neurodegenerative and inflammatory disorders, visceral and neuropathic pain, irritable bowel syndrome, diabetes, kidney failure, bladder incontinence and cancer, as well as disorders if the special senses, airways, skin, cardiovascular, and musculoskeletal systems.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical SchoolLondon, UK
- Department of Pharmacology, The University of MelbourneMelbourne, VIC, Australia
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25
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Sekino Y, Nakano J, Hamaue Y, Chuganji S, Sakamoto J, Yoshimura T, Origuchi T, Okita M. Sensory hyperinnervation and increase in NGF, TRPV1 and P2X3expression in the epidermis following cast immobilization in rats. Eur J Pain 2013; 18:639-48. [DOI: 10.1002/j.1532-2149.2013.00412.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/10/2013] [Indexed: 12/31/2022]
Affiliation(s)
- Y. Sekino
- Department of Locomotive Rehabilitation Science; Unit of Rehabilitation Sciences; Nagasaki University Graduate School of Biomedical Sciences; Japan
| | - J. Nakano
- Department of Physical Therapy Science; Unit of Physical and Occupational Therapy Sciences; Nagasaki University Graduate School of Biochemical Sciences; Japan
| | - Y. Hamaue
- Department of Locomotive Rehabilitation Science; Unit of Rehabilitation Sciences; Nagasaki University Graduate School of Biomedical Sciences; Japan
| | - S. Chuganji
- Department of Physical Therapy Science; Unit of Physical and Occupational Therapy Sciences; Nagasaki University Graduate School of Biochemical Sciences; Japan
| | - J. Sakamoto
- Department of Rehabilitation; Nagasaki University Hospital; Japan
| | - T. Yoshimura
- Department of Locomotive Rehabilitation Science; Unit of Rehabilitation Sciences; Nagasaki University Graduate School of Biomedical Sciences; Japan
| | - T. Origuchi
- Department of Locomotive Rehabilitation Science; Unit of Rehabilitation Sciences; Nagasaki University Graduate School of Biomedical Sciences; Japan
| | - M. Okita
- Department of Locomotive Rehabilitation Science; Unit of Rehabilitation Sciences; Nagasaki University Graduate School of Biomedical Sciences; Japan
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26
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Pyridoxine for prevention of hand-foot syndrome caused by chemotherapy: a systematic review. PLoS One 2013; 8:e72245. [PMID: 23977264 PMCID: PMC3748123 DOI: 10.1371/journal.pone.0072245] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 07/05/2013] [Indexed: 12/18/2022] Open
Abstract
Background Hand-foot syndrome (HFS) is a relatively frequent dermatologic toxic reaction to certain anti-cancer chemotherapies. The syndrome can evolve into a distressing condition that limits function and affects quality of life. Pyridoxine (vitamin B6) has been used empirically for the prevention of HFS caused by anti-cancer therapy. However, evidence of its efficacy remains controversial. Methodology//Principal Findings Systematic literature searches were conducted on the Cochrane Library, PUBMED, EMBASE, LILACS, CBM, CNKI, VIP, WANFANG and the U.S. ClinicalTrials.gov website. We included all related randomized controlled trials (RCTs) irrespective of language. Reviewers from different professions independently assessed all potential studies and extracted data. Subgroup analysis was planned according to dose of pyridoxine. 5 RCTs involving 607 patients were contributed to the meta-analysis. No significant differences were found between patients receiving pyridoxine and placebo for prevention of incidence of HFS and grade 2 or worse HFS (relative risk (RR) 0.96, 95%confidence interval (CI) 0.86–1.06; RR0.95, 95%CI 0.73–1.24, respectively). Similarly, no significant improvement in quality of life was detected among patients. However, significant difference was found for prevention of grade 2 or worse HFS with pyridoxine 400 mg daily compared to 200 mg (RR0.55, 95%CI 0.33–0.92). Conclusions/Significance There is inadequate evidence to make any recommendation about using pyridoxine for prevention of HFS caused by chemotherapy. However, pyridoxine 400 mg may have some efficacy. Further studies of large sample sizes are needed to evaluate the efficacy and safety of pyridoxine, especially at high dose, in comparison with placebo.
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In vivo imaging demonstrates ATP release from murine keratinocytes and its involvement in cutaneous inflammation after tape stripping. J Invest Dermatol 2013; 133:2407-2415. [PMID: 23552799 DOI: 10.1038/jid.2013.163] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Revised: 02/26/2013] [Accepted: 03/13/2013] [Indexed: 12/20/2022]
Abstract
Adenosine 5'-triphosphate (ATP) release from keratinocytes has been observed in various stress models in vitro, but studies demonstrating epidermal ATP release in vivo are limited. To visualize extracellular ATP (eATP) in vivo, we developed enhanced green-emitting luciferase immobilized on agarose beads (Eluc-agarose). Subcutaneous injection of Eluc-agarose together with ATP into the dorsal skin of BALB/c mice following intraperitoneal luciferin injection produced detectable and measurable bioluminescence using an in vivo imaging system. Using Eluc-agarose, we demonstrated in vivo that bright bioluminescence was observed from 1 to 20 minutes after repeated tape stripping of murine skin. This bioluminescence was suppressed by the local administration of apyrase. Eluc-agarose bioluminescence was observed only in tape-stripped skin with transepidermal water loss (TEWL) between 100 and 140 g m(2) h(-1), indicating a loss of bioluminescence with excessive tape stripping (TEWL>140 g m(-2) h(-1)). Histologically, tape-stripped skin with detectable eATP had a viable epidermis and a subepidermal neutrophil infiltrate, and administration of apyrase reduced the inflammatory infiltrate. Neither a viable epidermis nor an upper dermal neutrophil infiltrate was observed after excessive tape stripping. These results suggest that tape stripping prompts ATP release from viable keratinocytes, which facilitates inflammatory cell migration. Eluc-agarose may be useful in the in vivo detection of eATP in murine models of skin diseases.
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Barr TP, Albrecht PJ, Hou Q, Mongin AA, Strichartz GR, Rice FL. Air-stimulated ATP release from keratinocytes occurs through connexin hemichannels. PLoS One 2013; 8:e56744. [PMID: 23457608 PMCID: PMC3574084 DOI: 10.1371/journal.pone.0056744] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 01/14/2013] [Indexed: 01/17/2023] Open
Abstract
Cutaneous ATP release plays an important role in both epidermal stratification and chronic pain, but little is known about ATP release mechanisms in keratinocytes that comprise the epidermis. In this study, we analyzed ATP release from cultured human neonatal keratinocytes briefly exposed to air, a process previously demonstrated to trigger ATP release from these cells. We show that exposing keratinocytes to air by removing media for 15 seconds causes a robust, long-lasting ATP release. This air-stimulated ATP release was increased in calcium differentiated cultures which showed a corresponding increase in connexin 43 mRNA, a major component of keratinocyte hemichannels. The known connexin hemichannel inhibitors 1-octanol and carbenoxolone both significantly reduced air-stimulated ATP release, as did two drugs traditionally used as ABC transporter inhibitors (glibenclamide and verapamil). These same 4 inhibitors also prevented an increase in the uptake of a connexin permeable dye induced by air exposure, confirming that connexin hemichannels are open during air-stimulated ATP release. In contrast, activity of the MDR1 ABC transporter was reduced by air exposure and the drugs that inhibited air-stimulated ATP release had differential effects on this transporter. These results indicate that air exposure elicits non-vesicular release of ATP from keratinocytes through connexin hemichannels and that drugs used to target connexin hemichannels and ABC transporters may cross-inhibit. Connexins represent a novel, peripheral target for the treatment of chronic pain and dermatological disease.
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Affiliation(s)
- Travis P. Barr
- Pain Research Center, Department of Anesthesiology, Perioperative and Pain Medicine, Brigham & Women's Hospital, Boston, Massachusetts, United States of America
| | - Phillip J. Albrecht
- Albany Medical College, Center for Neuroscience and Neuropharmacology, Albany, New York, United States of America
| | - Quanzhi Hou
- Albany Medical College, Center for Neuroscience and Neuropharmacology, Albany, New York, United States of America
| | - Alexander A. Mongin
- Albany Medical College, Center for Neuroscience and Neuropharmacology, Albany, New York, United States of America
| | - Gary R. Strichartz
- Pain Research Center, Department of Anesthesiology, Perioperative and Pain Medicine, Brigham & Women's Hospital, Boston, Massachusetts, United States of America
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Frank L. Rice
- Albany Medical College, Center for Neuroscience and Neuropharmacology, Albany, New York, United States of America
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Donnelly S, English G, de Zwart-Storm EA, Lang S, van Steensel MAM, Martin PE. Differential susceptibility of Cx26 mutations associated with epidermal dysplasias to peptidoglycan derived from Staphylococcus aureus and Staphylococcus epidermidis. Exp Dermatol 2012; 21:592-8. [PMID: 22643125 DOI: 10.1111/j.1600-0625.2012.01521.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/27/2012] [Indexed: 12/28/2022]
Abstract
Mutations in Connexin26 (Cx26) give rise to a spectrum of dominantly inherited hyperproliferating skin disorders, the severest being keratitis-ichthyosis-deafness (KID) syndrome, an inflammatory skin disorder, with patients prone to opportunistic infections. We compared the effects of peptidoglycan (PGN) extracted from the skin commensal Staphylococcus epidermidis and the opportunistic pathogen Staphylococcus aureus on interleukin-6 and connexin expression in HaCaT cells (a keratinocyte cell line) and connexin channel activity in HaCaT and HeLa (connexin deficient) cells transfected to express KID and non-KID Cx26 mutations. In both cell types, PGN from S. aureus induced hemichannel activity in cells expressing KID mutants as monitored by ATP release assays following 15-min challenge, while that from S. epidermidis evoked a response in HeLa cells. In KID mutant expressing cells, ATP release was significantly higher than in cells transfected with wild-type Cx26. No ATP release was observed in non-KID mutant transfected cells or in the presence of carbenoxolone, a connexin channel blocker. PGN isolated from S. aureus but not S. epidermidis induced interleukin-6 and Cx26 expression in HaCaT cells following 6-h challenge. Challenge by PGN from S. aureus evoked a greater interleukin-6 response in cells expressing KID mutants than in cells expressing wtCx26 or non-KID mutants. This response returned to basal levels if acute KID hemichannel signalling was blocked prior to PGN challenge. Thus, KID mutants form channels that can be triggered by the pro-inflammatory mediator PGN from opportunistic pathogens but not skin commensals, providing further insight into the genotype-phenotype relationship of Cx26 disorders.
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Affiliation(s)
- Steven Donnelly
- Department of Life Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Scotland, UK
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Denda S, Takei K, Kumamoto J, Goto M, Tsutsumi M, Denda M. Oxytocin is expressed in epidermal keratinocytes and released upon stimulation with adenosine 5'-[γ-thio]triphosphate in vitro. Exp Dermatol 2012; 21:535-7. [PMID: 22583056 DOI: 10.1111/j.1600-0625.2012.01507.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/05/2012] [Indexed: 01/15/2023]
Abstract
Oxytocin is a neuropeptide produced primarily in the hypothalamus and is best known for its roles in parturition and lactation. It also influences behaviour, memory and mental state. Recent studies have suggested a variety of roles for oxytocin in peripheral tissues, including skin. Here we show that oxytocin is expressed in human skin. Immunohistochemical studies showed that oxytocin and its carrier protein, neurophysin I, are predominantly localized in epidermis. RT-PCR confirmed the expression of oxytocin in both skin and cultured epidermal keratinocytes. We also show that oxytocin is released from keratinocytes after application of adenosine 5'-[γ-thio]triphosphate (ATPγS, a stable analogue of ATP) in a dose-dependent manner. The ATPγS-induced oxytocin release was inhibited by removal of extracellular calcium, or by the P2X receptor antagonist 2',3'-O-(2,4,6-trinitrophenyl)adenosine 5'-triphosphate (TNP-ATP). These results suggest that oxytocin is produced in human epidermal keratinocytes and is released in response to calcium influx via P2X receptors.
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Burnstock G, Knight GE, Greig AV. Purinergic Signaling in Healthy and Diseased Skin. J Invest Dermatol 2012; 132:526-46. [DOI: 10.1038/jid.2011.344] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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32
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Kawamura T, Ogawa Y, Nakamura Y, Nakamizo S, Ohta Y, Nakano H, Kabashima K, Katayama I, Koizumi S, Kodama T, Nakao A, Shimada S. Severe dermatitis with loss of epidermal Langerhans cells in human and mouse zinc deficiency. J Clin Invest 2012; 122:722-32. [PMID: 22214844 DOI: 10.1172/jci58618] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Accepted: 11/16/2011] [Indexed: 12/22/2022] Open
Abstract
Zinc deficiency can be an inherited disorder, in which case it is known as acrodermatitis enteropathica (AE), or an acquired disorder caused by low dietary intake of zinc. Even though zinc deficiency diminishes cellular and humoral immunity, patients develop immunostimulating skin inflammation. Here, we have demonstrated that despite diminished allergic contact dermatitis in mice fed a zinc-deficient (ZD) diet, irritant contact dermatitis (ICD) in these mice was more severe and prolonged than that in controls. Further, histological examination of ICD lesions in ZD mice revealed subcorneal vacuolization and epidermal pallor, histological features of AE. Consistent with the fact that ATP release from chemically injured keratinocytes serves as a causative mediator of ICD, we found that the severe ICD response in ZD mice was attenuated by local injection of soluble nucleoside triphosphate diphosphohydrolase. In addition, skin tissue from ZD mice with ICD showed increased levels of ATP, as did cultured wild-type keratinocytes treated with chemical irritants and the zinc-chelating reagent TPEN. Interestingly, numbers of epidermal Langerhans cells (LCs), which play a protective role against ATP-mediated inflammatory signals, were decreased in ZD mice as well as samples from ZD patients. These findings suggest that upon exposure to irritants, aberrant ATP release from keratinocytes and impaired LC-dependent hydrolysis of nucleotides may be important in the pathogenesis of AE.
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Affiliation(s)
- Tatsuyoshi Kawamura
- Department of Dermatology, Faculty of Medicine, University of Yamanashi, Yamanashi, Japan.
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Abstract
During embryonic development, the skin, the largest organ of the human body, and nervous system are both derived from the neuroectoderm. Consequently, several key factors and mechanisms that influence and control central or peripheral nervous system activities are also present and hence involved in various regulatory mechanisms of the skin. Apparently, this is the case for the ion and non-ion selective channels as well. Therefore, in this review, we shall focus on delineating the regulatory roles of the channels in skin physiology and pathophysiology. First, we introduce key cutaneous functions and major characteristics of the channels in question. Then, we systematically detail the involvement of a multitude of channels in such skin processes (e.g. skin barrier formation, maintenance, and repair, immune mechanisms, exocrine secretion) which are mostly defined by cutaneous non-neuronal cell populations. Finally, we close by summarizing data suggesting that selected channels are also involved in skin diseases such as e.g. atopic dermatitis, psoriasis, non-melanoma cancers and malignant melanoma, genetic and autoimmune diseases, etc., as well as in skin ageing.
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Affiliation(s)
- Attila Oláh
- DE-MTA Lendület Cellular Physiology Research Group, Department of Physiology, University of Debrecen, Medical and Health Science Center, Research Center for Molecular Medicine, Nagyerdei krt. 98, H-4032, Debrecen, Hungary
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Ryanodine Receptors Are Expressed in Epidermal Keratinocytes and Associated with Keratinocyte Differentiation and Epidermal Permeability Barrier Homeostasis. J Invest Dermatol 2012; 132:69-75. [DOI: 10.1038/jid.2011.256] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Tsutsumi M, Goto M, Denda S, Denda M. Morphological and functional differences in coculture system of keratinocytes and dorsal-root-ganglion-derived cells depending on time of seeding. Exp Dermatol 2011; 20:464-7. [PMID: 21585554 DOI: 10.1111/j.1600-0625.2011.01276.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Previous study indicated that in a coculture system of keratinocytes and dorsal-root-ganglion-derived (DRG) cells, mechanical stimulation of keratinocytes induced ATP-mediated calcium propagation and excitation of DRG cells. Here, we examined two different coculture systems of keratinocytes and DRG cells. In one, we seeded keratinocytes first and then seeded DRG cells on the keratinocytes. In this system, nerve fibres from DRG cells passed between keratinocytes. Mechanical stimulation of keratinocytes did not induce excitation of DRG cells. In the other, we seeded both cell types together. At first, each cell type grew separately, forming cell aggregates. Then, nerve fibres grew out from the DRG cell aggregates to keratinocyte aggregates and penetrated into them. In this system, mechanical stimulation of keratinocytes induced excitation of the nerve fibres, but the excitation was not completely blocked by apyrase, an ATP-degrading enzyme. These results suggest that coculture of keratinocytes and DRG can generate a variety of structures, depending on the seeding conditions.
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Affiliation(s)
- Moe Tsutsumi
- Shiseido Research Center, Kanazawa-ku, Yokohama, Japan
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36
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Abstract
Cx (connexin) proteins are components of gap junctions which are aqueous pores that allow intercellular exchange of ions and small molecules. Mutations in Cx genes are linked to a range of human disorders. In the present review we discuss mutations in β-Cx genes encoding Cx26, Cx30, Cx30.3 and Cx31 which lead to skin disease and deafness. Functional studies with Cx proteins have given insights into disease-associated mechanisms and non-gap junctional roles for Cx proteins.
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Distribution of ecto-nucleotidases in mouse sensory circuits suggests roles for nucleoside triphosphate diphosphohydrolase-3 in nociception and mechanoreception. Neuroscience 2011; 193:387-98. [PMID: 21807070 DOI: 10.1016/j.neuroscience.2011.07.044] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Revised: 06/28/2011] [Accepted: 07/18/2011] [Indexed: 12/27/2022]
Abstract
Nucleotide-activated P2X channels and P2Y metabotropic receptors participate in nociceptive signaling. Agonist availability is regulated by nucleoside triphosphate diphosphohydrolase-1 (NTPDase1), -2, -3, and -8, a family of enzymes that hydrolyze extracellular ATP to generate ADP (a P2Y agonist) and AMP. They provide a major source of extracellular AMP, the substrate for adenosine production by ecto-5'-nucleotidase (NT5E), and thereby regulate adenosine (P1) receptor signaling. NTPDases vary in their efficiency of tri- and diphosphate hydrolysis; therefore, which family members are expressed impacts nucleotide availability and half-life. This study employed enzyme activity histochemistry to examine the distribution of ATPase activity and immunohistochemistry for NTPDase1, 2, 3, and 8 in dorsal root ganglion (DRG) and spinal cord. Nucleotidase activity was robust in spinal dorsal horn, confirming that nociceptive pathways are a major site of nucleotide transmission. In DRG, extensive staining revealed ATPase activity in a subset of neurons and in non-neuronal cells. mRNA for NTPDase1-3, but not NTPDase8, was detected in lumbar DRG and spinal cord. Immunoreactivity for NTPDase3 closely matched the distribution of ATPase activity, labeling DRG central projections in the dorsal root and superficial dorsal horn, as well as intrinsic spinal neurons concentrated in lamina II. In DRG, NTPDase3 co-localized with markers of nociceptors and with NT5E. In addition, labeling of a subset of larger-diameter neurons in DRG was consistent with intense staining of Meissner corpuscle afferents in glabrous skin. Merkel cells and terminal Schwann cells of hair follicle afferents were also labeled, but the axons themselves were negative. We propose that NTPDase3 is a key regulator of nociceptive signaling that also makes an unexpected contribution to innocuous tactile sensation.
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Roles of transient receptor potential proteins (TRPs) in epidermal keratinocytes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 704:847-60. [PMID: 21290330 DOI: 10.1007/978-94-007-0265-3_44] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Epidermal keratinocytes are the epithelial cells of mammalian skin. At the basal layer of the epidermis, these cells proliferate strongly, and as they move towards the skin surface, differentiation proceeds. At the uppermost layer of the epidermis, keratinocytes undergo apoptosis and die, forming a thin, water-impermeable layer called the stratum corneum. Peripheral blood vessels do not reach the epidermis, but peripheral nerve fibers do penetrate into it. Until recently, it was considered that the main role of epidermal keratinocytes was to construct and maintain the water-impermeable barrier function. However, since the functional existence of TRPV1, which is activated by heat and low pH, in epidermal keratinocytes was identified, our understanding of the role of keratinocytes has changed enormously. It has been found that many TRP channels are expressed in epidermal keratinocytes, and play important roles in differentiation, proliferation and barrier homeostasis. Moreover, because TRP channels expressed in keratinocytes have the ability to sense a variety of environmental factors, such as temperature, mechanical stress, osmotic stress and chemical stimuli, epidermal keratinocytes might form a key part of the sensory system of the skin. The present review deals with the potential roles of TRP channels expressed in epidermal keratinocytes and focuses on the concept of the epidermis as an active interface between the body and the environment.
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Antimicrobial and anti-inflammatory effects of Cecropin A(1-8)-Magainin2(1-12) hybrid peptide analog p5 against Malassezia furfur infection in human keratinocytes. J Invest Dermatol 2011; 131:1677-83. [PMID: 21593770 DOI: 10.1038/jid.2011.112] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The lipophilic fungus Malassezia furfur (M. furfur) is a commensal microbe associated with several chronic diseases such as pityriasis versicolor, folliculitis, and seborrheic dermatitis. Because M. furfur-related diseases are difficult to treat and require prolonged use of medications, the treatment for M. furfur-related skin diseases is supposed to gain control over M. furfur growth and the inflammation associated with it, as well as to prevent secondary infections. In this study, we investigated the antifungal and anti-inflammatory effects of cecropin A(1-8)-magainin 2(1-12) hybrid peptide analog P5 on M. furfur. The minimal inhibitory concentration of P5 against M. furfur was 0.39 μM, making it 3-4 times more potent than commonly used antifungal agents such as ketoconazole (1.5 μM) or itraconazole (1.14 μM). P5 efficiently inhibited the expression of IL-8 and Toll-like receptor 2 in M. furfur-infected human keratinocytes without eukaryotic cytotoxicity at its fungicidal concentration. Moreover, P5 significantly downregulated NF-κB activation and intracellular calcium fluctuation, which are closely related with enhanced responses of keratinocyte inflammation induced by M. furfur infection. Taken together, these observations suggest P5 may be a potential therapeutic agent for M. furfur-associated human skin diseases because of its distinct antifungal and anti-inflammatory action.
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Azorin N, Raoux M, Rodat-Despoix L, Merrot T, Delmas P, Crest M. ATP signalling is crucial for the response of human keratinocytes to mechanical stimulation by hypo-osmotic shock. Exp Dermatol 2011; 20:401-7. [PMID: 21355886 DOI: 10.1111/j.1600-0625.2010.01219.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Touch is detected through receptors located in the skin and the activation of channels in sensory nerve fibres. Epidermal keratinocytes themselves, however, may sense mechanical stimulus and contribute to skin sensation. Here, we showed that the mechanical stimulation of human keratinocytes by hypo-osmotic shock releases adenosine triphosphate (ATP) and increases intracellular calcium. We demonstrated that the release of ATP was found to be calcium independent because emptying the intracellular calcium stores did not cause ATP release; ATP release was still observed in the absence of external calcium and it persisted on chelating cytosolic calcium. On the other hand, the released ATP activated purinergic receptors and mobilized intracellular calcium stores. The resulting depletion of stored calcium led to the activation of capacitative calcium entry. Increase in cytosolic calcium concentration was blocked by the purinergic receptor blocker suramin, phospholipase C inhibitor and apyrase, which hydrolyses ATP. Collectively, our data demonstrate that human keratinocytes are mechanically activated by hypo-osmotic shock, leading first to the release of ATP, which in turn stimulates purinergic receptors, resulting in the mobilization of intracellular calcium and capacitative calcium entry. These results emphasize the crucial role of ATP signalling in the transduction of mechanical stimuli in human keratinocytes.
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Affiliation(s)
- Nathalie Azorin
- Université de la Méditerranée, Centre National de la Recherche Scientifique (CNRS) UMR6231, Marseille, France
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41
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Burnstock G, Kennedy C. P2X receptors in health and disease. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2011; 61:333-372. [PMID: 21586364 DOI: 10.1016/b978-0-12-385526-8.00011-4] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Seven P2X receptor subunits have been cloned which form functional homo- and heterotrimers. These are cation-selective channels, equally permeable to Na(+) and K(+) and with significant Ca(2+) permeability. The three-dimensional structure of the P2X receptor is described. The channel pore is formed by the α-helical transmembrane spanning region 2 of each subunit. When ATP binds to a P2X receptor, the pore opens within milliseconds, allowing the cations to flow. P2X receptors are expressed on both central and peripheral neurons, where they are involved in neuromuscular and synaptic neurotransmission and neuromodulation. They are also expressed in most types of nonneuronal cells and mediate a wide range of actions, such as contraction of smooth muscle, secretion, and immunomodulation. Changes in the expression of P2X receptors have been characterized in many pathological conditions of the cardiovascular, gastrointestinal, respiratory, and urinogenital systems and in the brain and special senses. The therapeutic potential of P2X receptor agonists and antagonists is currently being investigated in a range of disorders, including chronic neuropathic and inflammatory pain, depression, cystic fibrosis, dry eye, irritable bowel syndrome, interstitial cystitis, dysfunctional urinary bladder, and cancer.
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Affiliation(s)
- G Burnstock
- Autonomic Neuroscience Centre, University College Medical School, London, United Kingdom
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von Gruenigen V, Frasure H, Fusco N, DeBernardo R, Eldermire E, Eaton S, Waggoner S. A double-blind, randomized trial of pyridoxine versus placebo for the prevention of pegylated liposomal doxorubicin-related hand-foot syndrome in gynecologic oncology patients. Cancer 2010; 116:4735-43. [DOI: 10.1002/cncr.25262] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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43
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Goto M, Ikeyama K, Tsutsumi M, Denda S, Denda M. Calcium ion propagation in cultured keratinocytes and other cells in skin in response to hydraulic pressure stimulation. J Cell Physiol 2010; 224:229-33. [PMID: 20432375 DOI: 10.1002/jcp.22121] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We have previously suggested that a variety of environmental factors might be first sensed by epidermal keratinocytes, which represent the frontier of the body. To further examine this idea, in the present study, we examined the intracellular calcium responses of cultured keratinocytes to external hydraulic pressure. First, we compared the responses of undifferentiated and differentiated keratinocytes with those of fibroblasts, vascular endothelial cells (VEC), and lymphatic endothelial cells. Elevation of intracellular calcium was observed after application of pressure to keratinocytes, fibroblasts, and VEC. The calcium propagation extended over a larger area and continued for a longer period of time in differentiated keratinocytes, as compared with the other cells. The response of the keratinocytes was dramatically reduced when the cells were incubated in medium without calcium. Application of a non-selective transient receptor potential (TRP) channel blocker also attenuated the calcium response. These results suggest that differentiated keratinocytes are sensitive to external pressure and that TRP might be involved in the mechanism of their response.
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Affiliation(s)
- Makiko Goto
- Shiseido Research Center, Kanazawa-ku, Yokohama, Japan.
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44
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Iriyama S, Matsunaga Y, Amano S. Heparanase activation induces epidermal hyperplasia, angiogenesis, lymphangiogenesis and wrinkles. Exp Dermatol 2010; 19:965-72. [DOI: 10.1111/j.1600-0625.2009.01027.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Denda S, Denda M, Inoue K, Hibino T. Glycolic acid induces keratinocyte proliferation in a skin equivalent model via TRPV1 activation. J Dermatol Sci 2010; 57:108-13. [PMID: 20060270 DOI: 10.1016/j.jdermsci.2009.11.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Revised: 11/13/2009] [Accepted: 11/30/2009] [Indexed: 10/20/2022]
Abstract
BACKGROUND Glycolic acid (GA) is the most commonly used alpha-hydroxy acid (AHA) for dermatologic applications, and is considered as a versatile superficial peeling agent for facial rejuvenation. Its therapeutic effect includes acceleration of epidermal turnover without apparent inflammation, and its action is pH-dependent. However, little is known about the molecular mechanism of GA-induced peeling. OBJECTIVE To investigate the effects of topical application of GA on cell proliferation using a skin equivalent model and to examine the molecular mechanisms of GA-induced peeling. METHODS GA solution was applied on the surface of a skin equivalent model, and cell proliferation was measured by means of BrdU-incorporation and immunohistochemical methods. Release of chemical mediators such as ATP into the medium was examined. The effects of antagonists of ion channels were also analyzed. RESULTS At 24h after GA application, BrdU-incorporation into basal keratinocytes was significantly increased. Induction of keratinocyte proliferation was pH-dependent, and was inhibited by antagonists of TRPV1, an acid-sensitive ion channel. Furthermore, transient ATP release was detected in the culture medium after GA stimulation, and this was also suppressed by TRPV1 antagonists. CONCLUSION These results suggest that one of the mechanisms of GA-induced epidermal proliferation is a growth response of basal keratinocytes to the local elevation of H(+)-ion concentration by infiltrated GA. This response is mediated by TRPV1 activation and ATP release. Activation of P2 receptors by the released ATP may also be involved.
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Affiliation(s)
- Sumiko Denda
- Shiseido Research Center, 2-12-1 Fukuura, Kanazawa-ku, Yokohama 236-8643, Japan
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Denda M, Nakatani M. Acceleration of permeability barrier recovery by exposure of skin to 10-30 kHz sound. Br J Dermatol 2009; 162:503-7. [DOI: 10.1111/j.1365-2133.2009.09509.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Tsutsumi M, Inoue K, Denda S, Ikeyama K, Goto M, Denda M. Mechanical-stimulation-evoked calcium waves in proliferating and differentiated human keratinocytes. Cell Tissue Res 2009; 338:99-106. [PMID: 19657674 DOI: 10.1007/s00441-009-0848-0] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Accepted: 07/10/2009] [Indexed: 10/20/2022]
Abstract
Calcium dynamics in the epidermis play a crucial role in barrier homeostasis and keratinocyte differentiation. We have recently suggested that the electro-physiological responses of the keratinocyte represent the frontier of the skin sensory system for environmental stimuli. In the present study, we have evaluated the responses of proliferating and differentiated human keratinocytes to mechanical stress by measuring the intracellular calcium level. Before differentiation, mechanical stress induces a calcium wave over a limited area; this is completely blocked by apyrase, which degrades ATP. In the case of differentiated keratinocytes, the calcium wave propagates over a larger area. Application of apyrase does not completely inhibit this wave. Thus, in differentiated cells, the induction of calcium waves might involve not only ATP, but also another factor. Immunohistochemical studies indicate that connexins 26 and 43, both components of gap junctions, are expressed in the cell membrane of differentiated keratinocytes. Application of octanol or carbenxolone, which block gap junctions, significantly reduces calcium wave propagation in differentiated keratinocytes. Thus, signaling via gap junctions might be involved in the induction of calcium waves in response to mechanical stress at the upper layer of the epidermis.
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Affiliation(s)
- Moe Tsutsumi
- Shiseido Research Center, 2-12-1, Fukuura, Kanazawa-ku, Yokohama, 236-8643, Japan
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Masaki H, Izutsu Y, Yahagi S, Okano Y. Reactive oxygen species in HaCaT keratinocytes after UVB irradiation are triggered by intracellular Ca(2+) levels. J Investig Dermatol Symp Proc 2009; 14:50-52. [PMID: 19675553 DOI: 10.1038/jidsymp.2009.12] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
It is recognized that reactive oxygen species (ROS) are responsible for skin damage due to UVB-radiation (UVB-R). However, the triggering substance(s) for ROS generation after UVB-R is uncertain with respect to the activation of NADPH oxidase (Nox), xanthine oxidase (XOD), and respiratory chain-chain reactions in mitochondria. As a first step in identifying the trigger(s) for UVB-induced ROS generation, we examined the relationship between Ca(2+) levels and ROS generation in HaCaT keratinocytes. UVB-R exposure of HaCaT keratinocytes resulted in an immediate elevation of ROS that recurred 7 hours later. This was accompanied by immediately elevated intracellular Ca(2+) . A Ca(2+) chelating agent, BAPTA, abolished the elevation of ROS after UVB-R completely. In addition, exogenous H(2)O(2) did not increase intracellular Ca(2+) levels. This suggests that intracellular Ca(2+) is the first trigger for UVB-induced ROS generation.Journal of Investigative Dermatology Symposium Proceedings (2009) 14, 50-52; doi:10.1038/jidsymp.2009.12.
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Affiliation(s)
- Hitoshi Masaki
- Cosmos Technical Center Co., LTD., 3-24-3 Hasune, Itabashi-Ku, Tokyo, Japan.
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Denda M. Methodology to improve epidermal barrier homeostasis: How to accelerate the barrier recovery? Int J Cosmet Sci 2009; 31:79-86. [DOI: 10.1111/j.1468-2494.2008.00487.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Nucleotide signaling and cutaneous mechanisms of pain transduction. ACTA ACUST UNITED AC 2008; 60:24-35. [PMID: 19171165 DOI: 10.1016/j.brainresrev.2008.12.013] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/29/2008] [Indexed: 11/21/2022]
Abstract
Sensory neurons that innervate the skin provide critical information about physical contact between the organism and the environment, including information about potentially-damaging stimuli that give rise to the sensation of pain. These afferents also contribute to the maintenance of tissue homeostasis, inflammation and wound healing, while sensitization of sensory afferents after injury results in painful hypersensitivity and protective behavior. In contrast to the traditional view of primary afferent terminals as the sole site of sensory transduction, recent reports have lead to the intriguing idea that cells of the skin play an active role in the transduction of sensory stimuli. The search for molecules that transduce different types of sensory stimuli (mechanical, heat, chemical) at the axon terminal has yielded a wide range of potential effectors, many of which are expressed by keratinocytes as well as neurons. Emerging evidence underscores the importance of nucleotide signaling through P2X ionotropic and P2Y metabotropic receptors in pain processing, and implicates nucleotide signaling as a critical form of communication between cells of the skin, immune cells and sensory neurons. It is of great interest to determine whether pathological changes in these mechanisms contribute to chronic pain in human disease states such as complex regional pain syndrome (CRPS). This review discusses recent advances in our understanding of communication mechanisms between cells of the skin and sensory axons in the transduction of sensory input leading to pain.
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