Association of serum vitamin D status with gestational diabetes mellitus and other laboratory parameters in early pregnant women.

BACKGROUND: The association between serum 25-hydroxy vitamin D (25(OH)D) status and gestational diabetes mellitus (GDM) gained attention in recent years, however the conclusion is still controversial due to many interfering factors, such as region of living, environment, lifestyle, and food supplements. Other metabolites (laboratory parameters) are also important in reflecting gestational states. This study aimed to investigate the association of serum 25(OH)D status in early pregnancy with GDM and other laboratory parameters in pregnant women. METHODS: A total of 1516 pregnant women whose blood glucose were normal before pregnancy in the city of Foshan in Guangdong, China were enrolled in this study. GDM was diagnosed between 24 to 28 weeks of pregnancy following the guidelines from the American Diabetes Association. Maternal serum 25(OH)D and other laboratory parameters-including hematology, coagulation, chemistry, and bone density-were measured utilizing various analytical methods in clinical laboratory at gestational weeks 11 to 14. RESULTS: The average 25(OH)D concentration was 59.1 ± 12.6 nmol/L. None of the study subjects had 25(OH)D < 25 nmol/L; 434 (28.6%) women had 25(OH)D deficiency (< 50 nmol/L), 882 women (58.2%) had 25(OH)D insufficiency (50-74 mmol/L) and 200 women (13.2%) had 25(OH)D sufficiency (≥ 75 nmol/L). There were 264 (17.4%) women diagnosed with GDM. There was not, however, an association between serum 25(OH)D in early pregnancy and GDM. Interestingly, women with more parity and high serum alkaline phosphatase levels had higher serum 25(OH)D levels. There was a possible positive association between serum 25(OH)D and pre-albumin, and a possible negative association between serum 25(OH)D, creatinine, and thrombin time. This study did not find an association between serum 25(OH)D and bone density. CONCLUSIONS: There were no associations between maternal serum 25(OH)D concentration in early pregnancy and the risk of GDM or bone density. There were, however, correlations between serum 25(OH)D and parity, seasoning at sampling, serum alkaline phosphatase, creatinine, pre-albumin, and coagulation factor thrombin time, which need further study to explain their pathophysiology and clinical significance.

[Vitamin D deficiency and carbohydrate metabolism in obese children and adolescents].

Obesity in childhood and adolescence is an important clinical and social problem in all countries, due to its extremely adverse long-term health effects. Vitamin D deficiency is extremely widespread in the world. Obesity and metabolic syndrome are often associated with vitamin D deficit. The role of vitamin D deficiency in obesity and metabolic syndrome in childhood is not well understood. Aims - to study the relationship of vitamin D deficiency and carbohydrate metabolism parameters in school children with obesity. Material and methods. The cross-sectional study included 71 patients of the Arkhangelsk Children's Clinical Hospital named after P.G. Vyhletsova (32 boys, 39 girls, aged 10 to 15 years, all children live in Arkhangelsk) with abdominal obesity. An anthropometric study was conducted: height (cm), body weight (kg), waist circumference (cm), body mass index (BMI). Serum 25(ОН)D level, fasting glycemia, insulin level and HOMA-IR index were assessed. Results. It has been revealed that 98,6% of children have vitamin D deficiency of varying severity. 25(OH)D level in severely obese children (BMI>3SDS) was significantly lower than in other obese children (BMI<3SDS): 12.8 [7.3-14.9] vs 13.5 [8.9-18.2] ng/ml, (p=0.039). In children with hyperglycemia and insulin resistance, 25(OH)D levels were significantly lower compared with those who had normal glycemic parameters and HOMA-IR index. Conclusions. The high prevalence of vitamin D deficiency in children and adolescents with overweight and obesity, progressing with increasing obesity severity, has been demonstrated. The association of glucose metabolism disorders with vitamin D deficiency has been shown.

Non-classical effects of vitamin D: Non-bone effects of vitamin D.

Our understanding of vitamin D has improved considerably in recent years. The role of vitamin D in preventing osteoporotic fractures is now well-established. However, an important controversy has emerged in the last decade concerning the effects of the active form of vitamin D (1,25-dihydroxy-vitamin D) on tissues other than bone (non-classical effects). The demonstration that the vitamin D receptor (VDR) is ubiquitously, expressed combined with increasing observational data supporting a relationship between the level of 25-hydroxy-vitamin D in the serum and chronic metabolic disorders, cardiovascular disease and neoplasms, have led to its redefinition as a steroid hormone and the proposal of its use in preventing and/or treating those diseases. This article is an update on the different non-bone or non-classical effects of "vitamin-hormone D", and its potential preventive or therapeutic role in certain diseases, however, this review is not exhaustive. The different modalities of substitution or supplementation proposed in France by the Groupe de Recherche et d'Information sur les Ostéoporoses (GRIO) are also summarised.

Vitamin D as a follicular marker of human oocyte quality and a serum marker of in vitro fertilization outcome.

PURPOSE: This study investigated the relationship between the vitamin D [25(OH)D] level in individual follicles and oocyte developmental competence. METHODS: A prospective cohort study in a private infertility center. Infertile women (N = 198) scheduled for intracytoplasmic sperm injection (ICSI) and a single embryo transfer (SET) provided serum samples and 322 follicular fluid (FF) specimens, each from a single follicle on the day of oocyte retrieval. RESULTS: FFs corresponding to successfully fertilized oocytes (following ICSI) contained significantly lower 25(OH)D level compared with those that were not fertilized (28.4 vs. 34.0 ng/ml, P = 0.001). Top quality embryos on the third day after fertilization, when compared to other available embryos, developed from oocytes collected from follicles containing significantly lower 25(OH)D levels (24.56 vs. 29.59 ng/ml, P = 0.007). Positive hCG, clinical pregnancy, and live birth rates were achieved from embryos derived from oocytes that grew in FF with significantly lower 25(OH)D levels than in follicles not associated with subsequent pregnancy. The concentration of 25(OH)D in FF in women with negative hCG was 32.23 ± 20.21 ng/ml, positive hCG 23.62 ± 6.09 ng/ml, clinical pregnancy 23.13 ± 6.09 ng/ml, and live birth 23.45 ± 6.11 ng/ml (P < 0.001). Women with serum 25(OH)D < 20 ng/ml had not only a higher fertilization rate (71 vs. 61.6%, P = 0.026) and a higher clinical pregnancy rate (48.2 vs. 25%, P = 0.001), but also higher miscarriage rate (14.5 vs. 3.8%, P = 0.013) compared with those with levels ≥ 20 ng/ml. CONCLUSION: This study reveals that the level of 25(OH)D in FF correlates negatively with the oocytes' ability to undergo fertilization and subsequent preimplantation embryo development. Oocytes matured in FF with low 25(OH)D concentration are more likely to produce top quality embryos and are associated with higher pregnancy and delivery rates. On the other hand, low serum vitamin D concentration is associated with higher miscarriage rates.

Association of Serum Vitamin D with Insulin Resistance and Beta Cell Function in Korean Health Checkup Examinees / 農村醫學 地域保健

OBJECTIVES: This study was conducted to examine the association of serum Vitamin D with insulin resistance and β-cell function in Korean health checkup examinees. METHODS: This study subjects were 374 healthy adults (199 males, 175 females) over the age of 20, who visited a general hospital medical center located in Haenam-gun, Jeollanam-do. To find the association of Vitamin D with HOMA-IR and HOMA-β, the used statistical analysis were ANOVA and ANCOVA. RESULTS: Of the study subjects, the level of serum Vitamin D defined by deficient group, insufficient group and sufficient group was 38.5%, 48.1% and 13.4%, respectively. According to the level of serum Vitamin D, the mean values of HOMA-IR were 1.92±1.08 in sufficient group, 1.99±1.04 in the insufficient group and 2.91±1.05 in deficient group and there were statistically significant different(p<0.001). The mean values of HOMA-β were 84.69±1.07 in sufficient group, 78.41±1.04 in the insufficient group and 80.48±1.04 in deficient group, and there were not significant. As a result of ANCOVA, adjusted mean of HOMA-IR were statistically significant different (p<0.001), but those of HOMA-β were not statistically significant according to the level of serum Vitamin D. CONCLUSIONS: The insufficient level of serum Vitamin D was relatively high in healthy adults who live in rural area, and it was found that HOMA-IR significantly increased when Vitamin D was deficient. To prevent insulin resistance or diabetes, it is necessary to provide sufficient information related to sufficient production of Vitamin D such as Vitamin D supplement, sun exposure, food intake and etc.

Efeitos contrastantes da vitamina D sobre a resposta imune inata e adquirida e seu impacto na recuperação da tuberculose / Contrasting effects of Vitamin D on innate and acquired immune responses and its impact on tuberculosis recover

A vitamina D é um hormônio essencial para o organismo, podendo ser obtida da dieta ou, principalmente, gerada pela pele após exposição à luz solar ultravioleta B. Na sua forma ativa (1,25(oH)2D) ela controla a absorção de cálcio e fósforo do intestino para a corrente sanguínea e participa de diversos processos celulares e fisiológicos. A ligação da 1,25(oH)2D ao receptor da vitamina D (VDr) presente em diversas células, como as células do sistema imunológico, induz a transcrição de genes que podem, por exemplo, modular a resposta imune inata e adquirida. A deficiência de vitamina D ou do VDR é associada a problemas de saúde como desordens esqueléticas, hipertensão, doenças cardiovasculares, diabetes mellitus, dislipidemias, doenças autoimunes e doenças infecciosas. Neste sentido, a suplementação com vitamina D tem sido proposta como uma possível medida preventiva, podendo ser aplicada em muitas patologias, em especial na tuberculose. Principal causa de morte por um único agente infeccioso, a tuberculose é responsável por cerca de 1,3 milhões de óbitos por ano no mundo. Publicações recentes apontam efeitos diversos da vitamina D na resposta imune inata e adquirida. A 1,25(oH)2D3 na presença do interferon (IFN)-γ é capaz de aumentar a atividade bactericida do macrófago contra o M. tuberculosis, aumentando a produção de peptídios antimicrobianos e estimulando a autofagia, favorecendo assim a lise de bacilos localizados em fagossomos. Por outro lado, a vitamina D em linfócitos T mostra efeito tolerogênico que favorece o controle de respostas inflamatórias excessivas. Neste trabalho de revisão são apresentados estudos recentes envolvendo efeitos da vitamina D na resposta imune inata e adquirida. Além disso, considerações sobre deficiência de vitamina D e maior risco de contrair tuberculose, e efeitos contrastantes da suplementação com vitamina D na prevenção e tratamento da TB, são discutidos.

Vitamin D is an essential hormone for the body, and can be obtained from diet or, mainly, generated by the skin after exposure to ultraviolet B sunlight. In its active form (1.25(oH)2D) it controls the absorption of calcium and phosphorus from the intestine into the bloodstream and participates in several cellular and physiological processes. Binding of 1,25(oH)2D to the Vitamin D receptor (VDr) present in several cells, such as cells of the immune system, induces transcription of genes that can, for example, modulate the innate and adaptive immune response. Deficiency of Vitamin D or VDr is associated with health problems such as skeletal disorders, hypertension, cardiovascular disease, diabetes mellitus, dyslipidemias, autoimmune diseases and infectious diseases. In this sense, Vitamin D supplementation has been proposed as a possible preventive measure and can be applied in several pathologies, especially in tuberculosis. main cause of death by a single infectious agent, tuberculosis accounts for about 1.3 million deaths per year worldwide. recent publications point to contrasting functions of Vitamin D in the innate and acquired immune response. 1.25(oH)2D3 in the presence of interferon (IFN)-γ is capable of increasing the bactericidal activity of the macrophage against M. tuberculosis, increasing the production of antimicrobial peptides and stimulating autophagy, thus favoring the lysis of bacilli located in phagosomes. on the other hand, Vitamin D in T lymphocytes shows a tolerogenic effect that favors the control of excessive inflammatory responses. In this review, recent studies involving Vitamin D effects on the innate and acquired immune responses are presented. In addition, considerations about Vitamin D deficiency and increased risk of contracting tuberculosis, and contrasting effects of Vitamin D supplementation on the prevention and treatment of TB, are discussed.

Vitamin D Deficiency in Adult Sickle Cell Patients.

INTRODUCTION: Vitamin D levels in adult black Americans with sickle cell disease (SCD) are comparatively lower than those found in the general population of black Americans. The objectives of this study were to examine the prevalence of Vitamin D deficiency (VDD) in adults with various subtypes of sickle cell disease and identify risk factors for vitamin D deficiency. METHODS: In a retrospective study serum Vitamin D25(OH)D and/or VitaminD1,25(OH)2D levels were obtained in 120 subjects with sickle cell disease. Baseline studies also included LFTs, total protein, albumin, total bilirubin, and creatinine levels. In a portion of subjects that were treated with oral ergocalciferol vitamin D levels and chemistries were obtained within 6 months of treatment. Data was statistically analyzed with Welch two sample t-tests and individual simple linear regressions (including logarithmic values) for each variable. RESULTS: Vitamin D25(OH)D levels were found to be significantly lower in a group of subjects with Hgb SS disease, than in a group with other subtypes of sickle cell disease. In both groups combined, significant (p = 0.05) and clinically suggestive negative correlations with Vitamin D25(OH)D were seen for total bilirubin and total protein, respectively. When total bilirubin and total protein levels were compared between the Hgb SS and HgbS/other groups, t-test revealed these levels were significantly higher in the Hgb SS group levels at p < 0.001 and p = 0.005, respectively. IMPLICATIONS: Low total Vitamin D25(OH)D levels in adults with sickle cell disease may be a reflection of chronic inflammation and overall disease severity.

The vitamin D metabolites 25(OH)D and 1,25(OH)2D are not related to either glucose metabolism or insulin action in obese women.

AIM: Vitamin D deficiency has been proposed to be involved in obesity-induced metabolic disease. However, data on the relationship between 25-hydroxycholecalciferol (25(OH)D) and insulin resistance have been inconsistent, and few studies have investigated the active vitamin D metabolite, 1,25-dihydroxycholecalciferol (1,25(OH)2D). This study aimed to determine the relationship between circulating levels of both 25(OH)D and 1,25(OH)2D and direct measures of glucose metabolism and insulin action in obese women. METHODS: Serum levels of 25(OH)D and 1,25(OH)2D, and glucose metabolism and tissue-specific insulin action, as assessed in the basal state and during a two-step euglycaemic-hyperinsulinaemic clamp study with [6,6-2H2]glucose infusion, were measured in 37 morbidly obese women (age: 43±10 years; body mass index: 44±6kg/m2). RESULTS: Sixteen subjects had circulating 25(OH)D levels<50nmol/L, consistent with vitamin D deficiency, and 21 had normal 25(OH)D levels. There were no differences in either baseline characteristics or parameters of glucose metabolism and insulin action between the groups. Serum 25(OH)D, but not 1,25(OH)2D, was negatively correlated with both body mass index (r=-0.42, P=0.01) and total body fat (r=-0.46, P<0.01). Neither 25(OH)D nor 1,25(OH)2D levels were related to any measured metabolic parameters, including fasting glucose, fasting insulin, basal endogenous glucose production, and hepatic, adipose-tissue and skeletal muscle insulin sensitivity. CONCLUSION: Obesity was associated with lower levels of circulating 25(OH)D, but not with the hormonally active metabolite 1,25(OH)2D. Neither 25(OH)D nor 1,25(OH)2D were related to glucose metabolism and tissue-specific insulin sensitivity in obese women, suggesting that vitamin D does not play a major role in obesity-related insulin resistance.

Epstein-Barr virus antibodies and vitamin D in prospective multiple sclerosis biobank samples.

BACKGROUND: The antibody reactivity against Epstein-Barr nuclear antigen-1 (EBNA-1), and 25-hydroxyvitamin D (25(OH)D) status have been associated with multiple sclerosis (MS) risk. Interaction between these two factors has been proposed. OBJECTIVES: The objective of this paper is to examine the association between antibody reactivity against EBNA-1 and five EBNA-1 domains, and the risk of MS, and to examine if these antibodies and 25(OH)D status interact regarding MS risk in prospectively collected blood samples. METHODS: Antibody reactivity and 25(OH)D levels were measured using ELISAs in n = 192 MS cases and n = 384 matched controls. The risk of MS was analysed using matched logistic regression. Interaction on the additive scale was assessed. RESULTS: The risk of MS increased across tertiles of antibody reactivity against EBNA-1, domain EBNA-1(402-502), and domain EBNA-1(385-420); p trends < 0.001. In young individuals (below median age at sampling, < 26.4 years), these associations were stronger, and 25(OH)D levels correlated inversely to antibody reactivity against EBNA-1 and the EBNA-1 domains. No statistical interaction was found. CONCLUSIONS: We confirm that increased antibody reactivity against EBNA-1 is a risk factor of MS. 25(OH)D status might influence the immune response towards Epstein-Barr virus in young subjects, and thereby modulate MS risk.

Influence of drugs on vitamin D and calcium metabolism.

In the past, interactions between drugs and vitamin D have received only little or no attention in the health care practices. However, since more and more drugs are used for the treatment of patients, this topic is increasingly relevant. Several drugs can interfere with the vitamin D and bone metabolism. Drugs that activate the pregnane X receptor can disrupt vitamin D metabolism and vitamin D function. Beside this, the medication oriented supplementation of vitamin D can ameliorate the pharmacologic action of some drugs, such as bisphosphonates, cytostatics and statins.

The association of Vitamin D and Parathyroid Hormone with Bone Mineral Density in Korean Postmenopausal Women

BACKGROUND: Osteoporosis results from bone loss due to menopause [estrogen(E) deficiency] and aging. Initial skeletal effect of menopause is accelerated bone resorption with an increase in seurm calcium(Ca) and compensatory but inadequate bone formation. Secretion of parathyroid hormone(PTH) is suppressed at this time. Postmenopausal osteoporosis results in fractures predominantly of trabecular bone, i.e., vertebra. With aging, secondary hyperparathyroidism by low serum Ca and vitamin D deficiency superim poses. Senile osteoporosis produces hip fractures, area of cortical bone. The aim of this study was to- examine the association of vitamin D[25(OH)D] and intact(i) PTH with bone mineral density(BMD) after controlling for suggested confounding factors, and the possibility of low serum vitamin D and high serum iPTH concentration could impact bone loss in Korean postmenopausal women. METHODS: Data from 188 postmenopausal Korean women aged 42 to 69 were analyzed through BMD, serum 25(OH)D, iPTH, Ca, phosphorus(P), alkaline phosphatase(ALP) and clinical characteristics. Factors affecting BMD was determined by Pearson correlation and the relationship between lumbar and femoral neck BMD and vitamin D[25(OH)D] and iPTH was assessed by multiple regression analysis after adjus- ting for suggested confounding factors. RESULTS: Lumbar and femoral neck BMD, serum Ca, P were decresaed and serum iPTH was increased with aging. In Pearson`s correlation, significant contributing factors to lumbar BMD was age, height, weight, menarche, year since menopause(YSM) and ALP. And significant contributing factors to femoral neck BMD was age, height, weight, menarche, YSM and iPTH. No relationship could be demonstrated between serum vitamin D[25(OH)D] and lumbar and femoral neck BMD. How ever, after controlling for potential confounding factors, a correlation was found between vitamin D[25(OH)D] and both of lumbar (p=0.013) and femoral neck BMD(p=0.077). iPTH was inversely related to femoral neck BMD(p=0.004) only in multiple linear regression. CONCLUSION: Serum vitamin D[25(OH)D] was influencing both of vertebral and femoral neck BMD, which suggests a significant role of vitamin D deficiency in the pathogenesis of postmenopausal osteo- porosis. In age related remodeling and loss of bone, increased serum iPTH might have additive role in cortical bone of femur. These findings suggest that vitamin D is very important for optimal bone health and a deleterious effect of increased iPTH on cortical bone loss. Adequate calcium and vitamin D status have to be maintained to prevent osteoporosis in postmenopausal Korean women.