Read by QxMD icon Read

Vitamin D keratinocytes

Jörg Reichrath, Roman Saternus, Thomas Vogt
During evolution, the ability of many organisms to synthesize vitamin D photochemically represented, and still represents, a major driving factor for the development of life on earth. In humans because not more than 10-20% of the requirement of vitamin D can be satisfied by the diet (under most living conditions in the US and Europe), the remaining 80-90% need to be photochemically synthesized in the skin through the action of solar or artificial ultraviolet-B (UV-B) radiation. The skin is a key organ of the human body's vitamin D endocrine system (VDES), representing both the site of vitamin D synthesis and a target tissue for biologically active vitamin D metabolites...
January 5, 2017: Photochemical & Photobiological Sciences
Zygmunt Zdrojewicz, Małgorzata Kowalik, Adam Jagodziński
Only 1-2% of people is red-headed but in the Russian Udmurt Republic or United Kingdom they can be met more often. A specific variant of MC1R gene (R allele) is responsible for the red hair. The gene encodes a receptor for melanocortins. These substances stimulate melanocytes to product melanin- a dye of the skin which is transported to keratinocytes. It protects a cellular nucleus from ultraviolet radiation. Melanin has two types: eumelanin which is dark brown or even black and red/orange pheomelanin. The second one is mostly observed in red-headed which is caused by R allele...
December 22, 2016: Polski Merkuriusz Lekarski: Organ Polskiego Towarzystwa Lekarskiego
Vaibhav Saini, Hengguang Zhao, Elizabeth T Petit, Francesca Gori, Marie B Demay
Vitamin D receptor (VDR) mutations in humans and mice cause alopecia. VDR-null mice (VDR(-/-)) exhibit lack of postmorphogenic hair cycles as a result of impaired keratinocyte stem cell (KSC) function. To identify the molecular basis for abnormal KSC function, RNA sequencing of wild-type (WT) and VDR(-/-) KSCs was performed. These studies demonstrated that >80% of differentially expressed genes are up-regulated in VDR(-/-) KSCs; thus, the VDR is a transcriptional suppressor in WT KSCs. Peroxisome proliferator-activated receptor γ (PPARγ), PPARγ coactivator 1β (PGC1β), and lipoprotein lipase (LPL) were among the up-regulated genes identified...
December 8, 2016: FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology
Hengguang Zhao, Sandra Rieger, Koichiro Abe, Martin Hewison, Thomas S Lisse
Mice and human patients with impaired vitamin D receptor (VDR) signaling have normal developmental hair growth but display aberrant post-morphogenic hair cycle progression associated with alopecia. In addition, VDR(-/-) mice exhibit impaired cutaneous wound healing. We undertook experiments to determine whether the stress-inducible regulator of energy homeostasis, DNA damage-inducible transcript 4 (Ddit4), is involved in these processes. By analyzing hair cycle activation in vivo, we show that VDR(-/-) mice at day 14 exhibit increased Ddit4 expression within follicular stress compartments...
November 26, 2016: International Journal of Molecular Sciences
B Bolerazska, M Rabajdova, I Spakova, M Marekova
The link between sunlight and skin cancer is a frequently discussed topic. However, ultraviolet radiation also induces the production of Vitamin D in the body. Keratinocytes and their ability to synthesize the active form of Vitamin D, which is consumed at the place of its origin in the skin, have a unique place in this discussion. We observe a remarkable sunshine-related paradox when we monitor the relationship between the dose of solar radiation and one type of skin cancer - malignant melanoma. Recent knowledge of the non-calcemic effects of Vitamin D, which include growth regulation, DNA repair, differentiation, apoptosis, membrane transport, metabolism, cell adhesion and oxidative stress, could help to further clarify this relationship...
November 24, 2016: Neoplasma
Sylvester Jusu, John F Presley, Richard Kremer
Human retinoid X receptor alpha (hRXRα) plays a critical role in DNA binding and transcriptional activity through heterodimeric association with several members of the nuclear receptor superfamily including the human vitamin D receptor (hVDR). We previously showed that hRXRα phosphorylation at serine 260 through the Ras-Raf-Mitogen activated protein kinase extra-cellular signal regulated kinases 1 and 2 (MAP kinase ERK1/2) activation is responsible for resistance to the growth inhibitory effects of 1α, 25dihydroxyvitamin D3 (1α,25(OH)2D3), the biologically active metabolite of vitamin D3 To further investigate the mechanism of this resistance we studied intranuclear dynamics of hVDR and hRXRα tagged constructs in living cells together with endogenous and tagged protein in fixed cells...
November 16, 2016: Journal of Biological Chemistry
Lazaros Belbasis, Irene Stefanaki, Alexander J Stratigos, Evangelos Evangelou
BACKGROUND: Skin cancers have a complex disease mechanism, involving both genetic and non-genetic risk factors. Numerous meta-analyses have been published claiming statistically significant associations between non-genetic risk factors and skin cancers without applying a thorough methodological assessment. OBJECTIVE: The present study maps the literature on the non-genetic risk factors of skin cancers, assesses the presence of statistical biases and identifies the associations with robust evidence...
December 2016: Journal of Dermatological Science
Susana Cubillos, Johannes Norgauer
Psoriasis is an inflammatory skin disease with or without joint involvement. In this disease, the thickened epidermis and impaired barrier are associated with altered calcium gradients. Calcium and vitamin D are known to play important roles in keratinocyte differentiation and bone metabolism. Intracellular calcium is regulated by calcium-sensing receptor (CASR), calcium release-activated calcium modulator (ORAI) and stromal interaction molecule (STIM). Other proteins modulated by vitamin D play important roles in calcium regulation e...
October 2016: International Journal of Molecular Medicine
Justyna M Wierzbicka, Michał A Żmijewski, Anna Piotrowska, Boguslaw Nedoszytko, Magdalena Lange, Robert C Tuckey, Andrzej T Slominski
Ultraviolet radiation B stimulates both the production of vitamin D3 in the skin and the activation of the skin analog of the hypothalamic-pituitary-adrenal axis (HPA) as well as the central HPA. Since the role of vitamin D3 in the regulation of the HPA is largely unknown, we investigated the impact of 1,25(OH)2D3 and its noncalcemic analogs, 20(OH)D3 and 21(OH)pD, on the expression of the local HPA in human epidermal keratinocytes. The noncalcemic analogs showed similar efficacy to 1,25(OH)2D3 in stimulating the expression of neuropeptides, CRF, urocortins and POMC, and their receptors, CRFR1, CRFR2, MC1R, MC2R, MC3R and MC4R...
December 5, 2016: Molecular and Cellular Endocrinology
Daniel D Bikle, Yan Jiang, Thai Nguyen, Yuko Oda, Chia-Ling Tu
1,25 dihydroxyvitamin D (1,25(OH)2D), the active metabolite of vitamin D, and calcium regulate epidermal differentiation. 1,25(OH)2D exerts its effects through the vitamin D receptor (VDR), a transcription factor in the nuclear hormone receptor family, whereas calcium acts through the calcium sensing receptor (Casr), a membrane bound member of the G protein coupled receptor family. We have developed mouse models in which the Vdr and Casr have been deleted in the epidermis ((epid) Vdr (-∕-) and (epid) Casr (-∕-))...
2016: Frontiers in Physiology
Jörg Reichrath, Christos C Zouboulis, Thomas Vogt, Michael F Holick
Vitamin D represents one of the major driving factors for the development of life on earth and for human evolution. While up to 10-20 % of the human organism's requirements in vitamin D can be obtained by the diet (under most living conditions in the USA and Europe), approximately 90 % of all needed vitamin D has to be photosynthesized in the skin through the action of the sun (ultraviolet-B (UV-B)). The skin represents a key organ of the human body's vitamin D endocrine system (VDES), being both the site of vitamin D synthesis and a target tissue for biologically active vitamin D metabolites...
September 2016: Reviews in Endocrine & Metabolic Disorders
Daniel Svensson, Daniel Nebel, Ulrikke Voss, Eva Ekblad, Bengt-Olof Nilsson
The biologically active form of vitamin D, 1α,25-dihydroxyvitamin D3 (1,25D3), has been reported to positively regulate the human cathelicidin anti-microbial peptide (CAMP) gene coding for LL-37, but the mechanisms are not completely understood. We have determined the expression of CAMP, vitamin D receptor (VDR), and the retinoid X receptor (RXR) isoforms in human skin and gingival tissue biopsies and investigated the signaling pathways involved in 1,25D3-induced upregulation of CAMP. Human skin and gingival biopsies exhibited few VDR-immunoreactive cells within the stratum basale, whereas rat colon enterocytes (positive control) possessed abundant VDR immunoreactivity...
June 30, 2016: Cell and Tissue Research
Jee-Bum Lee, Soo Hyeon Bae, Ki Rang Moon, Eui Young Na, Sook Jung Yun, Seung-Chul Lee
Cathelicidin (LL-37), Toll-like receptor 2 (TLR-2) and kallikreins (KLKs) are key inflammatory mediators in rosacea. Laser or light-based devices have been successfully used for rosacea. We investigated the effects of light-emitting diodes (LEDs) on LL-37, KLKs, TLR-2 and protease activity in cultured normal human epidermal keratinocytes (NHEKs) and rosacea-like mouse skin (RLMS). LL-37, KLK5, KLK7 and vitamin D receptor were induced by 1α, 25-dihydroxyvitamin D3 (VD3 ) and TLR-2 by Ad-CMV transfection in cultured NHEKs...
June 17, 2016: Experimental Dermatology
Ester Ziv, Ruth Koren, Muayad A Zahalka, Amiram Ravid
Several inflammatory mediators increase calcitriol production by epidermal keratinocytes. In turn calcitriol attenuates the keratinocyte inflammatory response. Since the effect of the in-situ generated calcitriol depends also on the sensitivity to the hormone we studied the effect of inflammatory cytokines on the response of HaCaT human keratinocytes to calcitriol by examining the expression and transcriptional activity of VDR. Treatment with TNF, but not with IL-1β or interferon γ, increased VDR protein level, while decreasing the level of its heterodimerization partner RXRα...
January 2016: Dermato-endocrinology
Marwa M T Fawzi, Sara Bahaa Mahmoud, Shereen Fathi Ahmed, Olfat Gamil Shaker
BACKGROUND: Alopecia areata (AA) is a frequent autoimmune disease, the pathogenesis of which is still unknown. Androgenetic alopecia (AGA) is a noncicatricial type of patterned hair loss. Expression of vitamin D receptors (VDRs) on keratinocytes is essential for maintenance of normal hair cycle, especially anagen initiation. OBJECTIVE: To assess VDRs in the skin and blood of AA and AGA patients, in order to evaluate their possible role in these hair diseases. METHODS: This study recruited 20 patients with AA, 20 patients with AGA, and 20 healthy controls...
May 6, 2016: Journal of Cosmetic Dermatology
Lena A VON Schuckmann, Matthew H Law, Grant W Montgomery, Adele C Green, Jolieke C VAN DER Pols
BACKGROUND: The vitamin D endocrine system is implicated in skin carcinogenesis and polymorphisms in genes associated with the vitamin D receptor (VDR) gene may alter the risk of keratinocyte cancers (basal cell carcinoma (BCC) and squamous cell carcinoma (SCC)). MATERIALS AND METHODS: In a nested case-control study of 1,124 adults, we investigated associations between polymorphisms in VDR-related pathways and incident keratinocyte cancers during 11 years of follow-up using adjusted multivariate regression analysis...
May 2016: Anticancer Research
Anna Piotrowska, Justyna Wierzbicka, Tomasz Ślebioda, Michał Woźniak, Robert C Tuckey, Andrzej T Slominski, Michał A Żmijewski
Although the skin production of vitamin D is initiated by ultraviolet radiation type B (UVB), the role vitamin D plays in antioxidative or pro-oxidative responses remains to be elucidated. We have used immortalized human HaCaT keratinocytes as a model of proliferating epidermal cells to test the influence of vitamin D on cellular response to H2O2 or the anti-cancer drug, cisplatin. Incubation of keratinocytes with 1,25(OH)2D3 or its low calcemic analogues, 20(OH)D3, 21(OH)pD or calcipotriol, sensitized cells to ROS resulting in more potent inhibition of keratinocyte proliferation by H2O2 in the presence of vitamin D compounds...
June 2016: Steroids
Leila J Mady, Dare V Ajibade, Connie Hsaio, Arnaud Teichert, Chak Fong, Yongmei Wang, Sylvia Christakos, Daniel D Bikle
The role for 1,25-dihydroxyvitamin D3 and/or calcium in hair follicle cycling is not clear despite their impact on keratinocyte differentiation. We found that calbindin-D9k null (knockout) pups generated from calbindin-D9k knockout females fed a vitamin D-deficient, low-calcium (0.47%) diet develop transient alopecia. The pups appear phenotypically normal until 13 days of age, after which the hair progressively sheds in a caudocephalic direction, resulting in truncal alopecia totalis by 20-23 days, with spontaneous recovery by 28 days...
July 2016: Journal of Investigative Dermatology
Carlo Mattozzi, Giovanni Paolino, Antonio Giovanni Richetta, Stefano Calvieri
Psoriasis is a common, inflammatory, chronic, relapsing skin disease. Despite several hypotheses having been postulated to explain the pathogenesis of this disorder, nowadays it is considered as a T-cell-mediated disease; in this context an important role is played by vitamin D. The role of this micronutrient is important for many reasons: it is able to modulate the immune system; it is implicated in keratinocyte turnover; and it is involved in the integrity of the cutaneous barrier. In psoriasis, this molecule plays an important role due to its ability in the modulation of innate and adaptive immunity and by its antiproliferative and pro-differentiative effects on keratinocytes...
May 2016: Journal of Dermatology
Venil N Sumantran, Pratik Mishra, Rakesh Bera, Natarajan Sudhakar
Cytochrome P450 drug metabolizing enzymes are implicated in personalized medicine for two main reasons. First, inter-individual variability in CYP3A4 expression is a confounding factor during cancer treatment. Second, inhibition or induction of CYP3A4 can trigger adverse drug-drug interactions. However, inflammation can downregulate CYP3A4 and other drug metabolizing enzymes and lead to altered metabolism of drugs and essential vitamins and lipids. Little is known about effects of inflammation on expression of CYP450 genes controlling drug metabolism in the skin...
2016: Pharmaceutics
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"