Vitamin D plays an important role in mineral and bone homeostasis, immune responses, cardiovascular function and keratinocyte proliferation and differentiation. Vitamin D performs most of its functions by binding to vitamin D receptors (VDR), which interact with other intracellular signaling pathways to regulate bone metabolism, inflammation, immunity, cell cycle progression and apoptosis. Autophagy is a basic stress response in yeast, plants and mammals, and plays a critical role in maintaining optimal functional states at the level of cells and organs. Vitamin D/VDR plays an anti-infection role via inducing and regulating autophagy.
Animals ; Autophagy ; Humans ; Inflammation ; Mammals/metabolism* ; Receptors, Calcitriol/metabolism* ; Vitamin D/physiology* ; Vitamins

Vitamin D (VD) is essential for bone health, and VD or its analogues are widely used in clinics to ameliorate bone loss. The targets and mode of VD anti-osteoporotic actions appear to be different from those of other classes of drugs modulating bone remodeling. VD exerts its biological activities through the nuclear VD receptor (VDR)-mediated transcriptional regulation of target mRNA and non-coding RNA genes. VD-induced gene regulation involves epigenetic modifications of chromatin conformation at the target loci as well as reconfiguration of higher-order chromosomal organization through VDR-mediated recruitment of various regulatory factors. Enhancer RNAs (eRNA), a class of non-coding enhancer-derived RNAs, have recently emerged as VDR target gene candidates that act through reorganization of chromatin looping to induce enhancer-promoter interaction in activation of mRNA-encoding genes. This review outlines the molecular mechanisms of VD actions mediated by the VDR and suggests novel function of eRNAs in VDR transactivation.
Bone Remodeling ; Chromatin ; Epigenomics ; Metabolism ; Receptors, Calcitriol ; RNA ; RNA, Messenger ; RNA, Untranslated ; Transcriptional Activation ; Vitamin D ; Vitamins

BACKGROUND: Vitamin is a well-known co-factor for many metabolic processes and its roles in fertility and follicular growth have been studied. Vitamin supplementation is frequently achieved by daily ingestion in the form of a complex capsule. However, the role of single and complex vitamins in in vitro maturation of murine follicles is not fully elucidated. METHODS: In this study, we evaluated the effects of two forms of vitamins. Pure L-ascorbic acid, and multi-vitamin (vitamin C+vitamin B complex) was treated at two different concentrations (50 and 100 µg/ml), to pre-puberty murine follicles during in vitro maturation. To determine the specific stage of growth that is affected by treatment with vitamins, the vitamins were treated from day 0, 4, 9, and 13. Growth of each follicle was assessed by measuring diameters of whole expanded area and of the granulosa cells. Expression of follicular and oocyte growth-related genes and the effect of vitamin on the viability of follicles was assessed using senescence associated β-galactosidase staining. RESULTS: Treatment with vitamins promoted the in vitro growth of murine follicles and the upregulated the expression of granulosa cell- and oocyte-specific genes such as BMP15, Fsh receptor, and GDF9. The proliferation of the granulosa cells was enhanced by the treatment of vitamin. Fifty µg/ml concentration vitamin showed greater effects compared to higher concentration. The viability of in vitro grown follicles was also significantly improved in vitamin-treated follicles. The effects of single L-ascorbic acid and complex vitamin were not significantly different to those of day 4 and day 9 follicles. Vitamins promoted murine follicle development in vitro with different effects on specific growth stage. CONCLUSION: Supplementation of vitamins during in vitro maturation of murine follicles is an efficient strategy for in vitro expansion of follicular cells. These results could be customized to the sophisticated culture of follicles retrieved from aged or cancer-survived female that contain smaller number of follicles with reduced potential to develop into mature follicles.
Aging ; Ascorbic Acid ; Eating ; Female ; Fertility ; Granulosa Cells ; Humans ; In Vitro Techniques ; Metabolism ; Oocytes ; Ovarian Follicle ; Receptors, FSH ; Vitamins

PURPOSE: Bone plays a role in glucose metabolism through the release of uncarboxylated osteocalcin into the systemic circulation. The identified novel roles for osteocalcin include increasing insulin secretion and sensitivity, energy expenditure, reduction of fat mass, and mitochondrial proliferation and functional enhancement. This study aimed to determine serum osteocalcin levels in overweight children and to investigate the relationships of osteocalcin with glucose metabolism and insulin sensitivity. METHODS: After overnight fasting, serum osteocalcin levels were measured in overweight (n=50) children between 6.0 and 12.9 years of age and nonoverweight controls (n=60). Height, weight, fasting serum glucose, insulin, alkaline phosphatase, total cholesterol, and 25 hydroxy vitamin D₃ (25(OH)VitD₃) were also measured in all subjects. RESULTS: There were significant differences in serum osteocalcin levels between the overweight and control groups (64.00±20.44 vs. 89.56±28.63, P<0.001). Serum osteocalcin levels were inversely correlated with body mass index (BMI) (r=-0.283, P=0.003), weight standard deviation score (SDS) (r=-0.222, P=0.020), BMI SDS (r=-0.297, P=0.002), insulin (r=-0.313, P=0.001), and homeostasis model assessment of insulin resistance (HOMA-IR) index (r=-0.268, P=0.005). In the subsequent multiple regression analyses, BMI, HOMA-IR, and age were determined to be independent predicting factors for serum osteocalcin. CONCLUSIONS: Our findings showed associations of serum osteocalcin with glucose metabolism and insulin sensitivity in overweight children, but we could not establish a causal relationship.
Alkaline Phosphatase ; Blood Glucose ; Body Mass Index ; Child ; Cholesterol ; Energy Metabolism ; Fasting ; Glucose ; Homeostasis ; Humans ; Insulin ; Insulin Resistance ; Metabolism ; Osteocalcin ; Overweight ; Vitamins

BACKGROUND: The objective of the current study is to determine the role of serum parathyroid hormone (PTH) on hip fracture development by retrospectively analyzing the relationship between vitamin D and PTH levels and hip fracture prevalence. METHODS: Among 288 patients over 50 years of age, 113 patients with hip fracture and 111 controls without fracture were analyzed after excluding patients with conditions affecting bone metabolism. Bone mineral density and serum biochemical markers were measured, while demographic data were obtained. Patients were divided into 4 groups according to serum 25-hydroxy-vitamin D (25-[OH]D) and PTH levels: LowD+LowP (low 25[OH]D and PTH); LowD+HighP, (low 25[OH]D and high PTH); HighD+LowP (high 25[OH]D and low PTH); and HighD+HighP, patients with (high 25[OH]D and PTH). Measured values and percentages of patients with hip fracture in each group were then determined and compared. RESULTS: The number of patients included in the LowD+LowP, LowD+HighP, HighD+LowP, and HighD+HighP groups was 116, 17, 87, and 4, while the percentages of patients with hip fracture in the same groups were 60.3%, 88.2%, 27.6%, and 100%, respectively. The percentage of hip fracture was significantly lower in the LowD+LowP than the LowD+HighP group (P=0.049). CONCLUSIONS: Patients with low serum 25(OH)D and PTH levels showed lower hip fracture prevalence, indicating the potential protective role of low PTH levels on bone health in patients with vitamin D deficiency. Therefore, clinicians should pay more attention to the possibility of fractures in patients with vitamin D deficiency who present with high PTH levels.
Biomarkers ; Bone Density ; Hip Fractures ; Hip ; Humans ; Hypoparathyroidism ; Metabolism ; Parathyroid Hormone ; Prevalence ; Retrospective Studies ; Vitamin D Deficiency ; Vitamin D ; Vitamins

OBJECTIVES: Vitamin D is regarded as one of the major nutrients that significantly influence bone metabolism. This study aims to look at the effect of supplementary vitamin D on bone mineral density (BMD) in female osteoporosis patients. METHODS: The retrospective hospital record review was performed on 282 patients who were diagnosed with osteoporosis and treated with selective estrogen receptor modulators (SERMs) between January 2015 and December 2016. Of these patients, 151 were treated with SERMs only while 131 were treated using both SERMs and vitamin D supplements. The BMD and any occurrence of osteoporotic fracture episode were investigated after one year. The result of two groups was compared to find the significance of vitamin D. RESULTS: Overall, improvement in BMD score was observed in 76% of the patients. The BMD of the SERMs only group improved by 3% in spine and 1% in the hip while that of the SERMs with vitamin D group improved by 6% and 1% respectively. Statistical significance was noticed in the spine only. One distal radius fracture and one single level vertebral fracture occurred in patients of SERMs group while two distal radius fractures occurred in SERMs with vitamin D group. There was no occurrence of around hip fracture in both groups. CONCLUSION: The result of the current study suggests that additional vitamin D may have some additive effect on improving BMD of the spine. Further study with the larger study population and the extended study period is recommended.
Bone Density ; Female ; Hip ; Hospital Records ; Humans ; Metabolism ; Osteoporosis ; Osteoporotic Fractures ; Radius Fractures ; Retrospective Studies ; Selective Estrogen Receptor Modulators ; Spine ; Vitamin D ; Vitamins

BACKGROUND/OBJECTIVES: Recent studies showed vitamin D deficiency is linked to chronic diseases in addition to skeletal metabolism which could threaten the elderly. We analyzed health conditions and socio-demographic factors associated with vitamin D deficiency in community dwelling people aged 65 years and older. SUBJECTS/METHOD: Data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2010 to 2012 were obtained. A total of 2,687 subjects aged 65 years and older were participated. The cutoff value of the Vitamin D deficiency was considered as serum 25-hydroxyvitamin D [25(OH)D] ≤ 20 ng/mL (50 nmol/L). RESULTS: The overall prevalence rate of vitamin D deficiency in the elderly was 62.1%. The factors such as female, obesity, metabolic syndrome, current smoker, and skipping breakfast were positively associated with vitamin D deficiency, but high intensity of physical activity and more than 9 hours of sleep duration were negatively associated with vitamin D deficiency (all P < 0.05). CONCLUSIONS: It is important that health professions know that the factors proved in this study are connected to vitamin D deficiency thus provide information and intervention strategies of vitamin D deficiency to old aged people.
Aged* ; Aging ; Breakfast ; Chronic Disease ; Female ; Health Occupations ; Humans ; Independent Living* ; Korea* ; Metabolism ; Motor Activity ; Nutrition Surveys ; Obesity ; Prevalence ; Risk Factors ; Vitamin D Deficiency* ; Vitamin D* ; Vitamins*

PURPOSE: Vitamin D plays an important role in calcium homeostasis and bone metabolism. It is associated with various diseases such as cardiovascular, immune, allergic and infectious disease. The aim of this study was to investigate the difference in clinical manifestations according to the concentration of vitamin D in mild bronchiolitis. METHODS: We performed a retrospective review of medical records of patients with mild bronchiolitis from November 2016 to April 2017 in Daegu Fatima Hospital. Mild bronchiolitis was classified by the modified Tal's score method. Patients were divided into 2 groups according to a 25-hydroxyvitamin D level of 20 ng/mL. We analyzed the clinical characteristics and laboratory data from the 2 groups. RESULTS: Of the 64 patients, 19 were included in the deficiency group and 45 in the normal group. Vitamin D levels were 11.7±4.9 ng/mL in the deficiency group and 28.8±5.0 ng/mL in the normal group. There were no differences in clinical features between both groups. However, the vitamin D deficiency group had significantly longer hospitalization than the normal group (6.78±2.74 days vs. 5.3±1.7 days, P=0.045). In the deficiency group, the incidence of previous respiratory diseases was significantly higher (P=0.001). No significant difference in blood and respiratory virus tests was observed. CONCLUSION: Low vitamin D levels in mild bronchiolitis were associated with longer hospitalization and prior respiratory disease. Vitamin D may affect the course of mild bronchiolitis.
Bronchiolitis* ; Calcium ; Communicable Diseases ; Daegu ; Homeostasis ; Hospitalization ; Humans ; Incidence ; Medical Records ; Metabolism ; Methods ; Retrospective Studies ; Vitamin D Deficiency ; Vitamin D* ; Vitamins*

OBJECTIVE: Autism spectrum disorder (ASD) is a complex neurodevelopmental syndrome with an increasingly prevalent etiology, yet not fully understood. It has been thought that vitamin D, complex B vitamin levels and homocysteine are associated with environmental factors and are important in ASD. The aim of this study was to examine serum vitamin D, vitamin D receptor (VDR), homocysteine, vitamin B6, vitamin B12 and folate levels in ASD. METHODS: In this study, serum vitamin D and VDR, homocysteine, vitamins B6, B12 and folate levels were determined in 60 patients with ASD (aged 3 to 12 years) and in 45 age-gender matched healthy controls. In addition, calcium, phosphorus and alkaline phosphatase, which are associated with vitamin D metabolism, were measured from serum in both groups. ASD severity was evaluted by the Childhood Autism Rating Scale (CARS). RESULTS: Serum vitamin D and VDR were substantially reduced in patients with ASD in comparision to control group. However, homocysteine level was significantly higher and vitamin B6, vitamin B12 and folate were also reduced in patients with ASD. Total CARS score showed a positive association with homocysteine and a negative correlation with vitamins D, B6, B12, folate and VDR. CONCLUSION: This comprehensive study, which examines many parameters has shown that low serum levels of vitamins D, B6, B12, folate and VDR as well as high homocysteine are important in the etiopathogenesis of ASD. However, further studies are required to define the precise mechanism(s) of these parameters and their contributions to the etiology and treatment of ASD.
Alkaline Phosphatase ; Autism Spectrum Disorder* ; Autistic Disorder* ; Calcium ; Child* ; Folic Acid ; Homocysteine ; Humans ; Metabolism ; Phosphorus ; Receptors, Calcitriol* ; Vitamin B 12 ; Vitamin B 6 ; Vitamin D* ; Vitamins*

Bile acids are major constituents of bile and known to help absorb dietary fat and fat-soluble vitamins in the gastrointestinal tract. In the past few decades, many studies have shown that bile acids not only play a role in fat digestion but also function as broad range of signal transduction hormones by binding to various receptors present in cell membranes or nuclei. Bile acid receptors are distributed in a wide range of organs and tissues in the human body. They perform multitudes of physiological functions with complex mechanisms. When bile acids bind to their receptors, they regulate fat and glucose metabolism in a tissue-specific way. In addition, bile acids are shown to inhibit inflammation and fibrosis in the liver. Considering the roles of bile acids as metabolic regulators, bile acids and their receptors can be very attractive targets in treating metabolic disorders. In the future, if roles of bile acids and their receptors are further clarified, they will be the novel target of drugs in the treatment of various metabolic diseases.
Bile Acids and Salts* ; Bile* ; Cell Membrane ; Dietary Fats ; Digestion ; Fibrosis ; Gastrointestinal Tract ; Glucose ; Human Body ; Inflammation ; Liver ; Metabolic Diseases ; Metabolism ; Signal Transduction ; Vitamins