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Boada MD, Gutierrez S, Eisenach JC. Effects of systemic oxytocin administration on ultraviolet B-induced nociceptive hypersensitivity and tactile hyposensitivity in mice. Mol Pain 2024; 20:17448069241226553. [PMID: 38172079 PMCID: PMC10846038 DOI: 10.1177/17448069241226553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 11/24/2023] [Accepted: 12/07/2023] [Indexed: 01/05/2024] Open
Abstract
Ultraviolet B (UVB) radiation induces cutaneous inflammation, leading to thermal and mechanical hypersensitivity. Here, we examine the mechanical properties and profile of tactile and nociceptive peripheral afferents functionally disrupted by this injury and the role of oxytocin (OXT) as a modulator of this disruption. We recorded intracellularly from L4 afferents innervating the irradiated area (5.1 J/cm2) in 4-6 old week male mice (C57BL/6J) after administering OXT intraperitoneally, 6 mg/Kg. The distribution of recorded neurons was shifted by UVB radiation to a pattern observed after acute and chronic injuries and reduced mechanical thresholds of A and C- high threshold mechanoreceptors while reducing tactile sensitivity. UVB radiation did not change somatic membrane electrical properties or fiber conduction velocity. OXT systemic administration rapidly reversed these peripheral changes toward normal in both low and high-threshold mechanoreceptors and shifted recorded neuron distribution toward normal. OXT and V1aR receptors were present on the terminals of myelinated and unmyelinated afferents innervating the skin. We conclude that UVB radiation, similar to local tissue surgical injury, cancer metastasis, and peripheral nerve injury, alters the distribution of low and high threshold mechanoreceptors afferents and sensitizes nociceptors while desensitizing tactile units. Acute systemic OXT administration partially returns all of those effects to normal.
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Affiliation(s)
- M Danilo Boada
- Department of Anesthesiology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Silvia Gutierrez
- Department of Anesthesiology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - James C Eisenach
- Department of Anesthesiology, Wake Forest School of Medicine, Winston-Salem, NC, USA
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Molitor LE, Rockwell K, Gould A, Mitchell MA. Effects of Short-Duration Artificial Ultraviolet B Exposure on 25-Hydroxyvitamin D 3 Concentrations in Domestic Rabbits ( Oryctolagus cuniculus). Animals (Basel) 2023; 13:ani13081307. [PMID: 37106870 PMCID: PMC10135136 DOI: 10.3390/ani13081307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 04/07/2023] [Indexed: 04/29/2023] Open
Abstract
Vitamin D is an important hormone that can be acquired through diet, exposure to ultraviolet B (UVB) radiation, or a combination of these methods. In domestic rabbits (Oryctolagus cuniculus), both methods appear viable, but there is limited research evaluating the effects of UVB on this species. Previous studies found that 12 h of artificial UVB radiation significantly increased 25-hydroxyvitamin D3 (25-OHD3) concentrations over time. While these findings suggest UVB can be beneficial in rabbits, this form of radiation can also be detrimental to vertebrates. The purpose of this study was to determine if shorter-duration UVB could elicit a similar physiological response in rabbits while minimizing potential negative effects. Six rabbits were used for this pilot study. The baseline serum 25-OHD3 was measured for each rabbit and following 14 days of 6 h/day exposure to artificial UVB, a second 25-OHD3 sample was collected. There was a significant increase (p = 0.001) in serum 25-OHD3 over time (Baseline: 27.7 ± 8.1 nmol/L; Day 14: 79.8 ± 9 nmol/L). This study affirmed that 6 h of UVB produced 25-OHD3 concentrations similar to those found in rabbits exposed to 12 h of UVB. Future studies should continue to determine how the duration of UVB exposure affects 25-OHD3 concentrations.
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Affiliation(s)
- Laure E Molitor
- Department of Veterinary Clinical Medicine, University of Illinois College of Veterinary Medicine, Urbana, IL 61802, USA
| | - Kelly Rockwell
- Department of Veterinary Clinical Medicine, University of Illinois College of Veterinary Medicine, Urbana, IL 61802, USA
| | - Amelia Gould
- Department of Veterinary Clinical Medicine, University of Illinois College of Veterinary Medicine, Urbana, IL 61802, USA
| | - Mark A Mitchell
- Department of Veterinary Clinical Medicine, University of Illinois College of Veterinary Medicine, Urbana, IL 61802, USA
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Cheng Y, Xia Q, Lu Z, Luan X, Fan L, Wang Z, Luo D. Maslinic acid attenuates UVB-induced oxidative damage in HFF-1 cells. J Cosmet Dermatol 2023. [PMID: 36943873 DOI: 10.1111/jocd.15730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 02/02/2023] [Accepted: 03/07/2023] [Indexed: 03/23/2023]
Abstract
BACKGROUND Oxidative damage is one of the major mechanisms of ultraviolet B (UVB)-induced damage to the skin. Maslinic acid (MA) is a natural compound of pentacyclic triterpene acids. It has been proved to have anti-inflammatory and antioxidant properties. OBJECTIVE This study aimed to explore the effects of MA on oxidative damage in human foreskin fibroblast cells (HFF-1) and the potential molecular mechanisms. METHODS A specific dose of UVB radiation was used to induce oxidative damage in HFF-1. Based on this, we performed measurements of cell proliferation, reactive oxygen species (ROS) levels, antioxidant enzyme activity, inflammation-related mediators, and NF-κB nuclear localization with or without the addition of MA. RESULTS MA significantly promoted cell proliferation viability at 10 and 20 μM. The addition of MA 24 h before UVB irradiation was more effective at enhancing cell proliferation and also produced lower ROS levels compared to co-cultured fibroblasts and MA for 24 h after irradiation. However, there was no statistically significant difference between groups at concentrations of 10 and 20 μM. The pretreatment group with MA had elevated superoxide dismutase and catalase activities, decreased IL-6 generation, and lowered mRNA levels of IL-6, TNF-α and MMP3 in comparison with the UVB-irradiated group without additional MA. Meanwhile, the nuclear translocation of NF-κB and the degradation of IκB were inhibited by MA pretreatment. CONCLUSION Taken together, these findings suggest that MA may alleviate UVB-induced oxidative damage in HFF-1 by inhibiting the nuclear translocation of NF-κB.
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Affiliation(s)
- Yuxin Cheng
- Department of Dermatology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China
| | - Qingyue Xia
- Department of Dermatology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China
| | - Zhiyu Lu
- Department of Dermatology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China
| | - Xingbao Luan
- Department of Dermatology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China
| | - Lipan Fan
- Department of Dermatology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China
| | - Zhaopeng Wang
- Department of Dermatology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China
| | - Dan Luo
- Department of Dermatology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China
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Estaji M, Mokhtari-Dizaji M, Movahedin M, Ghaffari Khaligh S. Non-invasive evaluation of elasticity of skin with the processing of ultrasound images during ultraviolet radiation: An animal photoaging model. Photodermatol Photoimmunol Photomed 2020; 37:131-139. [PMID: 33098351 DOI: 10.1111/phpp.12622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 10/02/2020] [Accepted: 10/19/2020] [Indexed: 11/30/2022]
Abstract
OBJECTIVE The aim of this study was to provide a non-invasive imaging method to evaluate the physical and mechanical parameters as a novelty method during skin photoaging. METHODS In order to evaluate the process of skin damage, 25 mice (C57BL6) were exposed to UVB radiation (0.03 mW/cm2 ), 5 times a week for 5 weeks. The thickness of the epidermal and dermal layers was measured weekly from the ultrasound images (40 MHz). The elastic parameters of the skin were estimated from the processing of the sequential ultrasound images with the motion detection algorithm during the injury generation process. RESULTS The thickening, Young modulus, and shear modulus of the dermal and epidermal layers during the UVB damage process significantly increased during the 5-week study period (P < .05). In addition, the percentage of changes in the thickness of the epidermal layer (0.22 ± 0.01 mm in day 0 to 0.37 ± 0.02 mm in day 35) and dermal layer (0.57 ± 0.05 mm in day 0 to 0.90 ± 0.08 mm in day 35) increased by 68% and 57%, respectively. Furthermore, Young modulus (154.41 ± 8.8 kPa) was 11 times more than that of non-irradiated skin (14.90 ± 2.2 kPa) and the shear modulus (2.33 ± 0.04 kPa) was 2.2 times more than non-irradiated skin (1.06 ± 0.04 kPa). CONCLUSION With processing the sequential ultrasound images and extracting the thickening, the elasticity of the skin layers can detect skin lesions by UVB radiation.
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Affiliation(s)
- Mohadese Estaji
- Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Manijhe Mokhtari-Dizaji
- Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mansoureh Movahedin
- Department of Anatomy, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Sahar Ghaffari Khaligh
- Department of Pathobiology, Faculty of Veterinary Medicine, Semnan University, Semnan, Iran
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Veronikis AJ, Cevik MB, Allen RH, Shirvani A, Sun A, Persons KS, Holick MF. Evaluation of a Ultraviolet B Light Emitting Diode (LED) for Producing Vitamin D 3 in Human Skin. Anticancer Res 2020; 40:719-722. [PMID: 32014913 DOI: 10.21873/anticanres.14002] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 12/30/2019] [Accepted: 01/10/2020] [Indexed: 11/10/2022]
Abstract
AIM A commercially available light emitting diode (LED) that transmitted narrow band ultraviolet B (UVB) radiation was evaluated for its efficacy and efficiency to produce vitamin D3 in human skin. MATERIALS AND METHODS Human skin samples were obtained from surgical procedures. The LED had peak emission wavelength of 295 nm. Skin samples were exposed to the UVB-LED for varying times and then were analyzed by high-pressure liquid chromatography (HPLC) to determine the vitamin D3 content. RESULTS There was a statistically significant time- and dose-dependent increase in the percent of 7-dehydrocholesterol that was converted to vitamin D3 in the skin type II samples; 1.3%±0.5, 2.3%±0.6 and 4.5%±1.67 after exposure to 0.75 (11.7 mJ/cm2), 1.5 (23.4 mJ/cm2) and 3 (46.8 mJ/cm2) minimal erythemal doses (MEDs), respectively. CONCLUSION The UVB-LED was effective and efficient in generating vitamin D3 in human skin, in vitro. The amount of vitamin D3 production increased in a dose-dependent fashion with increased UVB energy. UVB-LEDs can be developed for devices that can efficiently produce vitamin D3 in human skin.
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Affiliation(s)
- Angeline J Veronikis
- Section of Endocrinology, Diabetes, Nutrition and Weight Management, Department of Medicine, Vitamin D, Skin, and Bone Research Laboratory, Boston University School of Medicine, Boston, MA, U.S.A
| | - Muhammet B Cevik
- Section of Endocrinology, Diabetes, Nutrition and Weight Management, Department of Medicine, Vitamin D, Skin, and Bone Research Laboratory, Boston University School of Medicine, Boston, MA, U.S.A
| | - Rachel H Allen
- Section of Endocrinology, Diabetes, Nutrition and Weight Management, Department of Medicine, Vitamin D, Skin, and Bone Research Laboratory, Boston University School of Medicine, Boston, MA, U.S.A
| | - Arash Shirvani
- Section of Endocrinology, Diabetes, Nutrition and Weight Management, Department of Medicine, Vitamin D, Skin, and Bone Research Laboratory, Boston University School of Medicine, Boston, MA, U.S.A
| | - Audrey Sun
- Section of Endocrinology, Diabetes, Nutrition and Weight Management, Department of Medicine, Vitamin D, Skin, and Bone Research Laboratory, Boston University School of Medicine, Boston, MA, U.S.A
| | - Kelly S Persons
- Section of Endocrinology, Diabetes, Nutrition and Weight Management, Department of Medicine, Vitamin D, Skin, and Bone Research Laboratory, Boston University School of Medicine, Boston, MA, U.S.A
| | - Michael F Holick
- Section of Endocrinology, Diabetes, Nutrition and Weight Management, Department of Medicine, Vitamin D, Skin, and Bone Research Laboratory, Boston University School of Medicine, Boston, MA, U.S.A.
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Hosseini M, Dousset L, Mahfouf W, Serrano-Sanchez M, Redonnet-Vernhet I, Mesli S, Kasraian Z, Obre E, Bonneu M, Claverol S, Vlaski M, Ivanovic Z, Rachidi W, Douki T, Taieb A, Bouzier-Sore AK, Rossignol R, Rezvani HR. Energy Metabolism Rewiring Precedes UVB-Induced Primary Skin Tumor Formation. Cell Rep 2018; 23:3621-34. [PMID: 29925003 DOI: 10.1016/j.celrep.2018.05.060] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 04/05/2018] [Accepted: 05/17/2018] [Indexed: 12/22/2022] Open
Abstract
Although growing evidence indicates that bioenergetic metabolism plays an important role in the progression of tumorigenesis, little information is available on the contribution of reprogramming of energy metabolism in cancer initiation. By applying a quantitative proteomic approach and targeted metabolomics, we find that specific metabolic modifications precede primary skin tumor formation. Using a multistage model of ultraviolet B (UVB) radiation-induced skin cancer, we show that glycolysis, tricarboxylic acid (TCA) cycle, and fatty acid β-oxidation are decreased at a very early stage of photocarcinogenesis, while the distal part of the electron transport chain (ETC) is upregulated. Reductive glutamine metabolism and the activity of dihydroorotate dehydrogenase (DHODH) are both necessary for maintaining high ETC. Mice with decreased DHODH activity or impaired ETC failed to develop pre-malignant and malignant lesions. DHODH activity represents a major link between DNA repair efficiency and bioenergetic patterning during skin carcinogenesis.
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Piao MJ, Kang KA, Zhen AX, Kang HK, Koh YS, Kim BS, Hyun JW. Horse Oil Mitigates Oxidative Damage to Human HaCaT Keratinocytes Caused by Ultraviolet B Irradiation. Int J Mol Sci 2019; 20:ijms20061490. [PMID: 30934595 PMCID: PMC6471125 DOI: 10.3390/ijms20061490] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 03/18/2019] [Accepted: 03/22/2019] [Indexed: 12/24/2022] Open
Abstract
Horse oil products have been used in skin care for a long time in traditional medicine, but the biological effects of horse oil on the skin remain unclear. This study was conducted to evaluate the protective effect of horse oil on ultraviolet B (UVB)-induced oxidative stress in human HaCaT keratinocytes. Horse oil significantly reduced UVB-induced intracellular reactive oxygen species and intracellular oxidative damage to lipids, proteins, and DNA. Horse oil absorbed light in the UVB range of the electromagnetic spectrum and suppressed the generation of cyclobutane pyrimidine dimers, a photoproduct of UVB irradiation. Western blotting showed that horse oil increased the UVB-induced Bcl-2/Bax ratio, inhibited mitochondria-mediated apoptosis and matrix metalloproteinase expression, and altered mitogen-activated protein kinase signaling-related proteins. These effects were conferred by increased phosphorylation of extracellular signal-regulated kinase 1/2 and decreased phosphorylation of p38 and c-Jun N-terminal kinase 1/2. Additionally, horse oil reduced UVB-induced binding of activator protein 1 to the matrix metalloproteinase-1 promoter site. These results indicate that horse oil protects human HaCaT keratinocytes from UVB-induced oxidative stress by absorbing UVB radiation and removing reactive oxygen species, thereby protecting cells from structural damage and preventing cell death and aging. In conclusion, horse oil is a potential skin protectant against skin damage involving oxidative stress.
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Affiliation(s)
- Mei Jing Piao
- School of Medicine, Jeju National University, Jeju 63243, Korea.
| | - Kyoung Ah Kang
- School of Medicine, Jeju National University, Jeju 63243, Korea.
| | - Ao Xuan Zhen
- School of Medicine, Jeju National University, Jeju 63243, Korea.
| | - Hee Kyoung Kang
- School of Medicine, Jeju National University, Jeju 63243, Korea.
| | - Young Sang Koh
- School of Medicine, Jeju National University, Jeju 63243, Korea.
| | - Bong Seok Kim
- Bio Convergence Center, Jeju Technopark, Jeju 63243, Korea.
| | - Jin Won Hyun
- School of Medicine, Jeju National University, Jeju 63243, Korea.
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8
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Hu Y, Ma Y, Wu S, Chen T, He Y, Sun J, Jiao R, Jiang X, Huang Y, Deng L, Bai W. Protective Effect of Cyanidin-3-O-Glucoside against Ultraviolet B Radiation-Induced Cell Damage in Human HaCaT Keratinocytes. Front Pharmacol 2016; 7:301. [PMID: 27656146 PMCID: PMC5013811 DOI: 10.3389/fphar.2016.00301] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 08/25/2016] [Indexed: 11/13/2022] Open
Abstract
Ultraviolet radiation is the major environmental harmful factor that has emotional impact on human skin. The aim of the present study was to determine the mechanism of protection of cyanidin-3-O-glucoside against ultraviolet B (UVB)-induced damage to human HaCaT keratinocytes. Our results show that cyanidin-3-O-glucoside decreased the levels of intracellular reactive oxygen species generated by UVB treatment. Cyanidin-3-O-glucoside also decreased the UVB-augmented levels of the DNA damage indicators phospho-p53 and phospho-ATM/ATR. In addition, cyanidin-3-O-glucoside protected keratinocytes from UVB-induced injury by overturning the disruption of mitochondrial membrane potential and reversing apoptosis. The expression of anti-apoptotic protein B-cell lymphoma 2 (Bcl-2) was attenuated in UVB-exposed cells but restored in UVB/cyanidin-3-O-glucoside-treated cells. Furthermore, expression of the proapoptotic proteins Bcl-2-associated X (Bax) and the key apoptosis executer cleaved caspase-3 were increased in UVB-irradiated cells and decreased in UVB/cyanidin-3-O-glucoside-treated cells. For these reasons, the results demonstrate that cyanidin-3-O-glucoside protects human keratinocytes against UVB-induced oxidative stress and apoptosis. Our study provides a theoretical basis for the use of cyanidin-3-O-glucoside in the fight against light damage.
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Affiliation(s)
- Yunfeng Hu
- Department of Dermatology, The First Affiliated Hospital of Jinan University, Jinan University Guangzhou, China
| | - Yuetang Ma
- Department of Dermatology, The First Affiliated Hospital of Jinan University, Jinan University Guangzhou, China
| | - Shi Wu
- Department of Dermatology, The First Affiliated Hospital of Jinan University, Jinan University Guangzhou, China
| | - Tianfeng Chen
- Department of Food Science and Engineering, Jinan University Guangzhou, China
| | - Yong He
- Department of Dermatology, The First Affiliated Hospital of Jinan University, Jinan University Guangzhou, China
| | - Jianxia Sun
- Faculty of Chemical Engineering and Light Industry, Guangdong University of Technology Guangzhou, China
| | - Rui Jiao
- Department of Food Science and Engineering, Jinan University Guangzhou, China
| | - Xinwei Jiang
- Department of Food Science and Engineering, Jinan University Guangzhou, China
| | - Yadong Huang
- Department of Food Science and Engineering, Jinan University Guangzhou, China
| | - Liehua Deng
- Department of Dermatology, The First Affiliated Hospital of Jinan University, Jinan University Guangzhou, China
| | - Weibin Bai
- Department of Food Science and Engineering, Jinan University Guangzhou, China
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9
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Holick MF. Biological Effects of Sunlight, Ultraviolet Radiation, Visible Light, Infrared Radiation and Vitamin D for Health. Anticancer Res 2016; 36:1345-1356. [PMID: 26977036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Humans evolved in sunlight and had depended on sunlight for its life giving properties that was appreciated by our early ancestors. However, for more than 40 years the lay press and various medical and dermatology associations have denounced sun exposure because of its association with increased risk for skin cancer. The goal of this review is to put into perspective the many health benefits that have been associated with exposure to sunlight, ultraviolet A (UVA) ultraviolet B (UVB), visible and infrared radiation.
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Affiliation(s)
- Michael F Holick
- Section of Endocrinology, Diabetes and Nutrition, Department of Medicine, Boston University Medical Center, Boston, MA, U.S.A.
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10
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Skobowiat C, Slominski AT. Ultraviolet B stimulates proopiomelanocortin signalling in the arcuate nucleus of the hypothalamus in mice. Exp Dermatol 2016; 25:120-3. [PMID: 26513428 PMCID: PMC4724293 DOI: 10.1111/exd.12890] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2015] [Indexed: 12/17/2022]
Abstract
We previously found that ultraviolet B (UVB) could stimulate the paraventricular nucleus (PVN) with activation the systemic hypothalamic-pituitary- adrenal (HPA) axis. To investigate whether UVB can also stimulate other hypothalamic nuclei, we tested its effect on the proopiomelanocortin (POMC) related signalling system in the arcuate nucleus (ARC) of female C57BL/6 and FVB albino mice. The shaved back skin of the mice was irradiated with either 100 or 400 mJ/cm2 of UVB. After 1, 3, 6 and 12 h, blood and hypothalamus were collected and processed for gene and protein expression, and measurement of α-MSH and β-endorphin (β-END) levels. An in situ immunohistochemical examination was performed for melanocortin receptor 4 (MC4R) and POMC-derived α-MSH. The expression of Pomc and MC4R mRNAs was stimulated, whereas that of AgRP was inhibited after exposure to UVB. It was accompanied by an increased number of both α-MSH- and MC4R-immunoreactive neurons in the ARC, and by increased levels of α-MSH and β-END (both found in the hypothalamus and plasma). This surprising discovery of UVB stimulating the POMC system in the ARC, accompanied by the increased plasma levels of α-MSH and β-END, paves the way for exciting areas of research on the communication between the skin and the brain, as well as is suggesting a new role for UVB in regulation of body metabolism.
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Affiliation(s)
- Cezary Skobowiat
- Departments of Pharmacodynamics and Molecular Pharmacology, The Ludwik Rydygier Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Andrzej T. Slominski
- Departments of Dermatology and Pathology, Laboratory Service of the VA Medical Center, University of Alabama Birmingham, Birmingham, AL, USA
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Abstract
Interest in Vitamin D has risen considerably recently with many athletes now advised to take daily vitamin D supplements. The reason for this interest is partly not only attributed to the resurgence of the Vitamin D-deficient disease rickets but also due to the discovery of a Vitamin D receptor in many tissues suggesting a more global role for Vitamin D than previously considered. Unlike the other vitamins that are obtained through the diet, Vitamin D is unique since endogenous synthesis following ultraviolet B (UVB) exposure is the predominant route of entry into systemic circulation. Moreover, Vitamin D could be better classed as a seco-steroid, given that its structure is similar to that of a steroid, and its production is derived from a cholesterol precursor (7-dehydrocholesteol) in the skin. The classification of Vitamin D status is currently subject to considerable debate with many authors opposing governing body recommendations. Regardless of the suggested optimal concentration, there is now growing evidence to suggest that many athletes are in fact Vitamin D deficient, especially in the winter months largely as a consequence of inadequate sun exposure, combined with poor dietary practices, although the consequences of such deficiencies are still unclear in athletic populations. Impaired muscle function and reduced regenerative capacity, impaired immune function, poor bone health and even impaired cardiovascular function have all been associated with low Vitamin D in athletes, however, to date, the majority of studies on Vitamin D have described associations and much more research is now needed examining causation.
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Affiliation(s)
- Daniel J Owens
- a Research Institute for Sport and Exercise Sciences , Liverpool John Moores University , Liverpool , UK
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12
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Abstract
It is becoming increasingly clear that vitamin D has a broad range of actions in the human body. Besides its well-known effects on calcium/phosphate homeostasis, vitamin D influences muscle function, cardiovascular homeostasis, nervous function, and the immune response. Vitamin D deficiency/insufficiency has been associated with muscle weakness and a high incidence of various chronic diseases such as cardiovascular disease, cancer, multiple sclerosis, and type 1 and 2 diabetes. Most importantly, low vitamin D status has been found to be an independent predictor of all-cause mortality. Several recent randomized controlled trials support the assumption that vitamin D can improve muscle strength, glucose homeostasis, and cardiovascular risk markers. In addition, vitamin D may reduce cancer incidence and elevated blood pressure. Since the prevalence of vitamin D deficiency/insufficiency is high throughout the world, there is a need to improve vitamin D status in the general adult population. However, the currently recommended daily vitamin D intake of 5-15 µg is too low to achieve an adequate vitamin D status in individuals with only modest skin synthesis. Thus, there is a need to recommend a vitamin D intake that is effective for achieving adequate circulating 25-hydroxyvitamin D concentrations (>75 nmol/L).
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Affiliation(s)
- Armin Zittermann
- Clinic for Thoracic and Cardiovascular Surgery, Heart and Diabetes Center North Rhine-Westphalia, Ruhr University Bochum, Georgstrasse 11, 32545 Bad Oeynhausen, Germany.
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