Topic Review
Vitamin D Signaling
The vitamin D metabolite 1α,25-dihydroxyvitamin D3 is the natural, high-affinity ligand of the transcription factor vitamin D receptor (VDR). In many tissues and cell types, VDR binds in a ligand-dependent fashion to thousands of genomic loci and modulates, via local chromatin changes, the expression of hundreds of primary target genes. Thus, the epigenome and transcriptome of VDR-expressing cells is directly affected by vitamin D. Vitamin D target genes encode for proteins with a large variety of physiological functions, ranging from the control of calcium homeostasis, innate and adaptive immunity, to cellular differentiation.
  • 556
  • 12 Apr 2022
Topic Review
Vitamin D Serum Concentrations and COVID-19
Active vitamin D [1,25(OH)2D3—calcitriol] is a secosteroid hormone whose receptor is expressed on all cells of the immune system. Vitamin D has a global anti-inflammatory effect and its role in the management of a SARS-CoV-2 infection has been investigated since the beginning of the COVID-19 pandemic.
  • 265
  • 23 Nov 2022
Topic Review
Vitamin D on Skin Aging
The normal vitamin D3 status is important for a general prevention of premature aging maintaining a healthful skin aging. Vitamin D3metabolites including its classical (1,25(OH)2D3) and novel (CYP11A1-intitated) D3hydroxyderivatives exert many beneficial protective effects on the skin, which could influence the process of premature aging via many different mechanisms, leading to a delay or attenuation of both chronological skin aging and photoaging. Skin-resident cells (keratinocytes, fibroblasts, and sebocytes) are capable of locally activating vitamin D3and exhibiting a diverse biological effect such as photoprotection and immunosuppression, similar to the UVR-induced one.
  • 699
  • 29 Sep 2021
Topic Review
Vitamin D on Immune System
Vitamin D deficiency, which causes an imbalance in bone remodeling, is a global public health problem and its frequency is increasing.
  • 498
  • 06 Dec 2021
Topic Review
Vitamin D Metabolism in Celiac Disease
Celiac disease is a chronic autoimmune disorder involving the small intestine, characterized by villous atrophy, crypt hyperplasia and an increase in intraepithelial lymphocytes. Due to both calcium malabsorption and immune activation, a high prevalence of bone mass derangement is evident in this condition, regardless of the presence of overt malabsorption. In untreated patients, secondary hyperparathyroidism is responsible for the hyperconversion of 25-vitamin D into 1,25-vitamin D making mandatory the determination of serum levels of both vitamin metabolites to avoid a wrong diagnosis of vitamin D deficit. A gluten-free diet allows for a normalization of bone and mineral metabolism, reverting these abnormalities and raising some doubts on the need for vitamin supplementation in all the patients. 
  • 616
  • 19 Jan 2023
Topic Review
Vitamin D in the Context of Evolution
For at least 1.2 billion years, eukaryotes have been able to synthesize sterols and, therefore, can produce vitamin D when exposed to UV-B. Vitamin D endocrinology was established some 550 million years ago in animals, when the high-affinity nuclear receptor VDR (vitamin D receptor), transport proteins and enzymes for vitamin D metabolism evolved. This enabled vitamin D to regulate, via its target genes, physiological process, the first of which were detoxification and energy metabolism. In this way, vitamin D was enabled to modulate the energy-consuming processes of the innate immune system in its fight against microbes. In the evolving adaptive immune system, vitamin D started to act as a negative regulator of growth, which prevents overboarding reactions of T cells in the context of autoimmune diseases. When, some 400 million years ago, species left the ocean and were exposed to gravitation, vitamin D endocrinology took over the additional role as a major regulator of calcium homeostasis, being important for a stable skeleton.
  • 325
  • 29 Jul 2022
Topic Review
Vitamin D in Sleep Disorders
Vitamin D is a fat-soluble vitamin, mainly synthesized in the body through ultraviolet B (UVB) exposure on the skin or taken orally through food and/or supplements.
  • 508
  • 11 Feb 2022
Topic Review
Vitamin D in Oral Diseases Development
Vitamin D is a fat-soluble secosteroid that plays a significant role in the whole body, including the maxillofacial region. The discovery of its receptors in many cells and organs made it possible to reveal the participation of vitamin D not only in the regulation of calcium phosphate metabolism, but also in immune processes, in providing anti-inflammatory and antimicrobial effects, slowing down cell proliferation and stimulating differentiation. In this literature review, we demonstrate the association between low vitamin D levels and the development of recurrent aphthous stomatitis, the course and response to treatment of squamous cell carcinoma of the oral cavity, the severity of periodontal diseases, and the processes of osseointegration and bone remodeling during dental implantation and guided tissue regeneration. 
  • 458
  • 17 Nov 2021
Topic Review
Vitamin D in NF1
Vitamin D is a fat-soluble steroid hormone playing a pivotal role in calcium and phosphate homeostasis as well as in bone health. Several investigations indicated that vitamin D action extends far beyond bone health and calcium metabolism, showing broad effects on a variety of critical illnesses, including cancer, infections, cardiovascular and autoimmune diseases. Epidemiological studies indicated that low circulating vitamin D levels inversely correlate with cutaneous manifestations and bone abnormalities, clinical hallmarks of neurofibromatosis type 1 (NF1). NF1 is an autosomal dominant tumour predisposition syndrome causing significant pain and morbidity, for which limited treatment options are available.
  • 917
  • 29 Jan 2021
Topic Review
Vitamin D in Long COVID-19
Coronavirus disease 2019 (COVID-19) has quickly become a global pandemic. Reports from different parts of the world indicate that a significant proportion of people who have recovered from COVID-19 are suffering from various health problems collectively referred to as “long COVID-19”. Common symptoms include fatigue, shortness of breath, cough, joint pain, chest pain, muscle aches, headaches, and so on. Vitamin D is an immunomodulatory hormone with proven efficacy against various upper respiratory tract infections. Vitamin D can inhibit hyperinflammatory reactions and accelerate the healing process in the affected areas, especially in lung tissue. Moreover, vitamin D deficiency has been associated with the severity and mortality of COVID-19 cases, with a high prevalence of hypovitaminosis D found in patients with COVID-19 and acute respiratory failure. However, no evidence has been found to support a role of vitamin D supplementation in reducing symptoms of long-COVID-19. On the other hand, having a higher vitamin D level before SARS-CoV-2 infection or raising it rapidly at the first symptoms of infection can significantly reduce the risk and severity of COVID-19.
  • 2.6K
  • 29 Apr 2022
  • Page
  • of
  • 1352
Video Production Service