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Topic Review
Vitamin E in Neuro-Nutrition
Vitamin E was first discovered by the American endocrinologist and anatomist Herbert. M. Evans, together with his assistant Katherine S. Bishop. The isolated substance, later termed vitamin E, describes a group of compounds consisting of four tocopherol (TP)- and four tocotrienol (TT)-derivatives.
  • 935
  • 27 Oct 2021
Topic Review
Vitamin E and cardiovascular diseases
Cardiovascular diseases (CVD) cause about 1/3 of global deaths. Therefore, new strategies for the prevention and treatment of cardiovascular events are highly sought-after. Vitamin E is known for significant antioxidative and anti-inflammatory properties, and has been studied in the prevention of CVD, supported by findings that vitamin E deficiency is associated with increased risk of cardiovascular events. However, randomized controlled trials in humans reveal conflicting and ultimately disappointing results regarding the reduction of cardiovascular events with vitamin E supplementation. As we discuss in detail, this outcome is strongly affected by study design, cohort selection, co-morbidities, genetic variations, age, and gender. For effective chronic primary and secondary prevention by vitamin E, oxidative and inflammatory status might not have been sufficiently antagonized. In contrast, acute administration of vitamin E may be more translatable into positive clinical outcomes. In patients with myocardial infarction (MI), which is associated with severe oxidative and inflammatory reactions, decreased plasma levels of vitamin E have been found. The offsetting of this acute vitamin E deficiency via short-term treatment in MI has shown promising results, and, thus, acute medication, rather than chronic supplementation, with vitamin E might revitalize vitamin E therapy and even provide positive clinical outcomes.
  • 1.2K
  • 13 Oct 2020
Topic Review
Vitamin E
Vitamin E is a common compound used for tocopherols and tocotrienols (α, β, γ, δ); it is the component of many natural products of both plant and animal origin. 
  • 1.9K
  • 12 Jul 2021
Topic Review
Vitamin D3 Hydroxyderivatives in Human
itamin D3 (D3) is produced in the skin in two steps. Initially there is a photochemical reaction caused by the action of UVB radiation (290–315 nm) on 7-dehydrocholesterol (7DHC) in which the B ring is broken producing pre-vitamin D3. In the second reaction, vitamin D3 is formed from pre-vitamin D3 by its thermal isomerization at 37 °C over several hours. Both the UVB intensity and the level of skin pigmentation affect the rate of vitamin D3 production. Vitamin D3 is a fat-soluble prohormonal secosteroid that has endocrine, paracrine and autocrine functions. Melanin absorbs UVB limiting the production of D3, and the same effect is achieved with clothing and sunscreen. Skin, more specifically the epidermis, has the full capacity to produce and activate vitamin D3.
  • 539
  • 07 Jul 2021
Topic Review
Vitamin D3 and Ischemic Stroke
Ischemic stroke is one of the major causes of death and permanent disability worldwide. The only efficient treatment to date is anticoagulant therapy and thrombectomy, which enable restitution of blood flow to ischemic tissues. Numerous promising neuroprotectants have failed in clinical trials. Given the complex pathomechanism of stroke, a multitarget pharmacotherapy seems a more rational approach in stroke prevention and treatment than drugs acting on single molecular targets. Vitamin D3 has emerged as a potential treatment adjunct for ischemic stroke, as it interferes with the key prosurvival pathways and shows neuroprotective, anti-inflammatory, regenerative and anti-aging properties in both neuronal and vascular tissue.
  • 508
  • 28 Nov 2022
Topic Review
Vitamin D: Cost-Effectively Overcoming Infections and Chronic Diseases
The prevalence of chronic diseases increases with age, especially in those with co-morbidities. The two most common denominators are the high prevalence of vitamin D deficiency and low concentrations of angiotensin-converting enzyme receptor-2 (ACE2). Whether vitamin D deficiency initiates or aggravates chronic diseases is unclear: the likelihood is both. Hypovitaminosis D negatively affects all body systems, especially the musculoskeletal and immune systems. Many chronic conditions and infections can be minimized using the right dose of vitamin D supplements administered at the right frequency (daily or once weekly) or direct sun exposure to one-third of the skin between 10:30 AM and 1:30 PM, in summer like sunlight, for 20 to 60 minutes depending on the skin tone. It is advisable to wear sunglasses and a brimmed hat to protect one’s eyes and face. Maintaining the population serum 25(OH)D concentration above 40 ng/mL (i.e., sufficiency) ensures a better immune system, minimizing symptomatic diseases and reducing infections and chronic diseases. The best clinical outcome and longevity are expected from maintaining the serum 25-hydroxyvitamin D concentrations between 50 and 80 ng/mL.
  • 952
  • 04 Sep 2023
Topic Review
Vitamin D, Sun Exposure and Skin Cancer
The current vitamin D deficiency epidemic is accompanied by an increase in endemic skin cancer. Ultraviolet (UV) exposure (neither artificial nor natural) is not the ideal source to synthesize vitamin D. There is conflicting epidemiological evidence regarding vitamin D, non-melanoma skin cancer (NMSC), and cutaneous melanoma (CMM), confounded by the effect of sun exposure and other factors. 
  • 424
  • 29 Mar 2022
Topic Review
Vitamin D, Oxidative-Stress and Aging
Recent advances in vitamin D research indicate that this vitamin, a secosteroid hormone, has beneficial effects on several body systems other than the musculoskeletal system. Both 25 dihydroxy vitamin D [25(OH)2D] and its active hormonal form, 1,25-dihydroxyvitamin D [1,25(OH)2D] are essential for human physiological functions, including damping down inflammation and the excessive intracellular oxidative stresses. Vitamin D is one of the key controllers of systemic inflammation, oxidative stress and mitochondrial respiratory function, and thus, the aging process in humans. In turn, molecular and cellular actions form 1,25(OH)2D slow down oxidative stress, cell and tissue damage, and the aging process. On the other hand, hypovitaminosis D impairs mitochondrial functions, and enhances oxidative stress and systemic inflammation. The interaction of 1,25(OH)2D with its intracellular receptors modulates vitamin D–dependent gene transcription and activation of vitamin D-responsive elements, which triggers multiple second messenger systems. Thus, it is not surprising that hypovitaminosis D increases the incidence and severity of several age-related common diseases, such as metabolic disorders that are linked to oxidative stress. These include obesity, insulin resistance, type 2 diabetes, hypertension, pregnancy complications, memory disorders, osteoporosis, autoimmune diseases, certain cancers, and systemic inflammatory diseases. Vitamin D adequacy leads to less oxidative stress and improves mitochondrial and endocrine functions, reducing the risks of disorders, such as autoimmunity, infections, metabolic derangements, and impairment of DNA repair; all of this aids a healthy, graceful aging process. Vitamin D is also a potent anti-oxidant that facilitates balanced mitochondrial activities, preventing oxidative stress-related protein oxidation, lipid peroxidation, and DNA damage. New understandings of vitamin D-related advances in metabolomics, transcriptomics, epigenetics, in relation to its ability to control oxidative stress in conjunction with micronutrients, vitamins, and antioxidants, following normalization of serum 25(OH)D and tissue 1,25(OH)2D concentrations, likely to promise cost-effective better clinical outcomes in humans. 
  • 1.9K
  • 29 Oct 2020
Topic Review
Vitamin D, microbiome, and IBD
Inflammatory bowel disease (IBD) is a chronic inflammation of the gastrointestinal tract (GIT), including Crohn’s disease (CD) and ulcerative colitis (UC), which differ in the location and lesion extensions. Both diseases are associated with microbiota dysbiosis, with a reduced population of butyrate-producing species, abnormal inflammatory response, and micronutrient deficiency (e.g., vitamin D hypovitaminosis). Vitamin D (VitD) is involved in immune cell differentiation, gut microbiota modulation, gene transcription, and barrier integrity. Vitamin D receptor (VDR) regulates the biological actions of the active VitD (1α,25-dihydroxyvitamin D3), and is involved in the genetic, environmental, immune, and microbial aspects of IBD. VitD deficiency is correlated with disease activity and its administration targeting a concentration of 30 ng/mL may have the potential to reduce disease activity. Moreover, VDR regulates functions of T cells and Paneth cells and modulates release of antimicrobial peptides in gut microbiota-host interactions. Meanwhile, beneficial microbial metabolites, e.g., butyrate, upregulate the VDR signaling.
  • 797
  • 31 Jan 2021
Topic Review
Vitamin D—Practical Considerations and Clinical Guidance
Empirical evidence establishes the connection between exposure and clinical outcomes. Clinical studies show that chronic diseases and infections can be prevented by proactively correcting vitamin D deficiency in individuals who are vitamin D deficient, and in the community. In RCTs, with proper daily or once-a-week vitamin D supplementation in the intervention group, the serum 25(OH)D concentration must be meaningfully increased to the above pre-planned level to ensure the validity of the clinical study. Clinical outcomes correlate well with the serum 25(OH)D concentrations but not necessarily with the administered doses. It is a common error by researchers and healthcare workers to assume that the amount taken automatically produces the stipulated serum levels.
  • 581
  • 01 Nov 2023
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