Search results for "25-hydroxyvitamin D"
showing 10 items of 13 documents
CYP27A1, CYP24A1, and RXR-α Polymorphisms, Vitamin D, and Multiple Sclerosis: a Pilot Study.
2018
Multiple sclerosis (MS) is a neurodegenerative autoimmune disease resulting from a complex interaction of genetic and environmental factors. Hypovitaminosis D seems to contribute to MS susceptibility as both an environmental and a genetic risk factor. The aim of our study was to investigate the association of SNPs in CYP27A1, CYP24A1, and RXR- α genes, vitamin D status, and MS risk. We performed a nested case-control study on patients with multiple sclerosis and healthy controls. Serum 25(OH)D3 levels and genotyping of CYP27A1, CYP24A1, and RXR-α -SNPs were investigated both in MS patients and in healthy controls. Serum 25(OH)D3 levels were measured by a high-performance liquid chromatograp…
Identification of polymorphic variants associated with erlotinib-related skin toxicity in advanced non-small cell lung cancer patients by DMET microa…
2016
Purpose: Erlotinib is a targeted agent commonly used in advanced non-small cell lung cancer (aNSCLC). However, drug-related skin toxicity often may affect the quality of life of cancer patients and lead to treatment discontinuation. Genetic polymorphisms in drug transporters and metabolizing enzymes play a major role in the interindividual variability in terms of efficacy and toxicity of erlotinib treatment. The aim of our study was to identify genetic determinants in adsorption, distribution, metabolism, and excretion genes influencing skin rash (SR) by the novel drug-metabolizing enzyme and transporter (DMET) microarray Affymetrix platform in aNSCLC patients. Methods: In a retrospective s…
VDBP, CYP27B1, and 25-Hydroxyvitamin D Gene Polymorphism Analyses in a Group of Sicilian Multiple Sclerosis Patients
2016
Multiple sclerosis (MS) is a chronic demyelinating disease of central nervous system regarded as one of the most common causes of neurological disability in young adults. The exact etiology of MS is not yet known, although epidemiological data indicate that both genetic susceptibility and environmental exposure are involved. A poor vitamin D status has been proposed as the most attractive environmental factor. Several evidence have highlighted the importance of mutations in vitamin D-regulating genes for vitamin D status. The purpose of our study was to assess the genetic variants of VDBP and CYP27B1 in MS patients and in a control group. A total of 192 subjects, including 100 MS patients a…
Factors influencing serum 25-hydroxivitamin D levels and other bone metabolism parameters in healthy older women
2016
Objective: Older women have frequently low serum 25-hydroxivitamin D (25[OH]D) concentrations, high parathormone (PTH) levels and low bone mineral density (BMD) values. Endogenous synthesis, dietary habits, sunlight exposure and fat-mass-mediated storage may influence 25(OH)D levels and bone metabolism, but the relevance of these factors in the elderly has yet to be fully elucidated. We aimed to investigate the influence of dietary vitamin D intake and fat mass on serum 25(OH)D levels and bone metabolism in older women. Design: Cross-sectional. Setting: Community. Participants: 218 fit older women attending a biweekly mild fitness program. Measurements: Dietary habits was investigated throu…
Vitamin D and clinical symptoms in First Episode Psychosis (FEP): A prospective cohort study
2019
BACKGROUND: There is a paucity of longitudinal research investigating vitamin D in people with early psychosis.METHOD: Vitamin D levels were measured in 168 patients (64% (n = 108) male, mean age 29.3 (9.8) years) with first episode psychosis (FEP), along with measures of clinical state at baseline and at 12 months follow up. We assessed the a) cross sectional, and; b) longitudinal relationships between continuous and categorical 25-hydroxyvitamin D (25(OH)D) levels and clinical symptoms at first contact for psychosis and at 12 months.RESULTS: In FEP, 80% (n = 134) at baseline, and 76% at 12 months follow up, had suboptimal vitamin D levels (<20 ng/ml). Suboptimal levels of 25 (OH) D at …
Evidence of a significant vitamin D deficiency among 9–13-year-old Polish children: results of a multicentre study
2018
Purpose To evaluate the extent to which the population of Polish preadolescents is vitamin D deficient and to assess seasonal variations in vitamin D status. Participants and methods A total of 720 healthy children aged 9–13 years (409 girls, 311 boys) residing in 6 representative geographical locations in Poland were studied. A parental-assisted questionnaire provided data on nutritional habits, vitamin D supplements and sun exposure. Serum concentration of 25-hydroxyvitamin was determined twice, after the winter in March and after the summer in October. Results In March, vitamin D deficiency (25–50 nmol/L) was found in 64%, and severe deficiency (< 25 nmol/L) in 20.2% of children. In Octo…
Serum 25-hydroxyvitamin d and the onset of late-life depressive mood in older men and women: the Pro.V.A. study.
2014
Depression is a debilitating chronic condition, and its diagnosis and treatment in elderly people are often challenging. Because depressive mood seems to follow a seasonal pattern, peaking in summer and winter (1), it has recently been suggested that, through its action on the hypothalamus (which is involved in mood regulation), vitamin D might account for the link between seasonal changes in photoperiod and seasonal mood swings (2). Acting as a neurosteroid hormone, vitamin D may regulate human and animal neurotransmission, neuroprotection, and neuroimmunomodulation (3), and nuclear vitamin D receptors have been located in the human cortex and hippocampus (4). Although an association betwe…
Regio- and stereoselective regulation of monooxygenase activities by isoenzyme-selective phosphorylation of cytochrome P450.
1989
The phosphorylation of the two major phenobarbital-inducible cytochrome P450 isoenzymes IIB1 and IIB2 was increased in hepatocytes by the action of the membrane permeating cAMP derivatives N6-dibutyryl-cAMP and 8-thiomethyl-cAMP. Under these conditions the dealkylation of 7-pentoxyresorufin, a selective substrate of cytochrome P450IIB1 and P450IIB2 was markedly reduced. 16 beta-Hydroxylation of testosterone which is catalyzed specifically only by cytochrome P450IIB1 and IIB2 was strongly reduced; for 16 alpha-hydroxylation which is also catalyzed by cytochrome P450IIB1 and IIB2 but additionally by 3 further cytochrome P450 isoenzymes, this reduction was less pronounced; for the oxidation of…
Severe hypovitaminosis D correlates with increased inflammatory markers in HIV infected patients
2013
Abstract Background Even though it has been suggested that antiretroviral therapy has an impact on severe hypovitaminosis D (SHD) in HIV infected patients, it could be speculated that the different levels of residual inflammation on HAART (Highly Active Anti Retroviral Therapy) could contribute to SHD and aggravate bone catabolism in these patients. Methods A cross-sectional study was carried out in an unselected cohort of 263 HIV infected outpatients consulting during Spring 2010. Clinical examinations were performed and medical history, food habits, sun exposure and addictions were collected. Fasting blood samples were taken for immunological, virological, inflammation, endocrine and bone…
Vitamin D Deficiency in Cushing’s Disease: Before and After Its Supplementation
2022
Background: The primary objective of the study was to assess serum 25-hydroxyvitamin D [25(OH)D] values in patients with Cushing’s disease (CD), compared to controls. The secondary objective was to assess the response to a load of 150,000 U of cholecalciferol. Methods: In 50 patients with active CD and 48 controls, we evaluated the anthropometric and biochemical parameters, including insulin sensitivity estimation by the homeostatic model of insulin resistance, Matsuda Index and oral disposition index at baseline and in patients with CD also after 6 weeks of cholecalciferol supplementation. Results: At baseline, patients with CD showed a higher frequency of hypovitaminosis deficiency (p = 0…