Hepatitis C ; metabolism ; Humans ; Vitamin D ; metabolism

Child ; Humans ; Hypersensitivity ; Vitamin D ; metabolism ; Vitamin D Deficiency ; Vitamins ; metabolism

Vitamin D plays a major role in bone metabolism, and its deficiency has an impact on fracture risk and healing. Low vitamin D levels are a cause of poor bone mineralization and have been associated with a significantly higher risk of physeal injury in children. This paper presents a case of a 13-year-old boy with a vitamin D deficiency, who sustained multiple sequential epiphyseal injuries at various areas. This report suggests that vitamin D deficiency is not only a significant cause of the clinical disease itself, but also an important factor affecting the successful recovery of injuries.
Adolescent ; Calcification, Physiologic ; Child ; Humans ; Male ; Metabolism ; Vitamin D Deficiency* ; Vitamin D* ; Vitamins*

BACKGROUND: Vitamin D deficiency remains common in all age groups and affects skeletal and non-skeletal health. Fibroblast growth factor 23 is a bone-derived hormone that regulates phosphate and 1,25-dihydroxyvitamin D homeostasis as a counter regulatory factor. 1,25-Dihydroxyvitamin D stimulates fibroblast growth factor 23 synthesis in bone, while fibroblast growth factor 23 suppresses 1,25-dihydroxyvitamin D production in the kidney. The aim of this study was to evaluate the effects of vitamin D₃ intramuscular injection therapy on serum fibroblast growth factor 23 concentrations, and several other parameters associated with bone metabolism such as sclerostin, dickkopf-1, and parathyroid hormone. METHODS: A total of 34 subjects with vitamin D deficiency (defined by serum 25-hydroxyvitamin D levels below 20 ng/mL) were randomly assigned to either the vitamin D injection group (200,000 units) or placebo treatment group. Serum calcium, phosphate, urine calcium/creatinine, serum 25-hydroxyvitamin D, fibroblast growth factor 23, sclerostin, parathyroid hormone, and dickkopf-1 levels were serially measured after treatment. RESULTS: Comparing the vitamin D injection group with the placebo group, no significant changes were observed in serum fibroblast growth factor 23, parathyroid hormone, or dickkopf-1 levels. Serum sclerostin concentrations transiently increased at week 4 in the vitamin D group. However, these elevated levels declined later and there were no statistically significant differences as compared with baseline levels. CONCLUSION: Serum fibroblast factor 23, sclerostin, parathyroid hormone, and dickkopf-1 levels were not affected significantly by single intramuscular injection of vitamin D₃.
Calcium ; Cholecalciferol ; Fibroblast Growth Factors* ; Fibroblasts* ; Homeostasis ; Humans ; Injections, Intramuscular ; Kidney ; Metabolism ; Parathyroid Hormone ; Vitamin D Deficiency* ; Vitamin D* ; Vitamins*

PURPOSE: This study was performed to investigate the relationship between serum vitamin D and parathyroid hormone (PTH) levels as well as to describe the prevalence and the risk factors of vitamin D deficiency (VDD) in Korean children. METHODS: Participants were 1,212 children aged 4 to 15 years, who visited Bundang CHA Medical Center (located at 37degreesN) between March 2012 and February 2013. Overweight was defined as body mass index> or =85th percentile. Participants were divided into 4 age groups and 2 seasonal groups. VDD was defined by serum 25-hydroxyvitamin D (25OHD) <20 ng/mL. RESULTS: The level of 25OHD was significantly lower in overweight group than in normal weight group (17.1+/-5.1 ng/mL vs. 19.1+/-6.1 ng/mL, P<0.001). Winter-spring season (odds ratio [OR], 4.46; 95% confidence interval [CI], 3.45-5.77), older age group (OR, 1.60; 95% CI, 1.36-1.88), and overweight (OR, 2.21; 95% CI, 1.62-3.01) were independently related with VDD. The PTH levels were significantly higher in VDD group compared to vitamin D insufficiency and sufficiency group (P<0.001). In normal weight children, 25OHD (beta=-0.007, P<0.001) and ionized calcium (beta=-0.594, P=0.007) were independently related with PTH, however, these associations were not significant in overweight children. CONCLUSION: VDD is very common in Korean children and its prevalence increases in winter-spring season, in overweight children and in older age groups. Further investigation on the vitamin D and PTH metabolism according to adiposity is required.
Adiposity ; Body Mass Index ; Calcium ; Child* ; Humans ; Metabolism ; Overweight ; Parathyroid Hormone* ; Prevalence* ; Risk Factors* ; Seasons ; Vitamin D ; Vitamin D Deficiency*

Recent cross-sectional and prospective studies suggest an association between vitamin D deficiency and type 2 diabetes mellitus risk. Vitamin D metabolism may play a role in diabetes mellitus pathogenesis independently of known risk factors. The decrease in vitamin D levels may occur through several mechanisms such as a decrease in the calcium concentration, an increase in parathyroid hormones, or a direct effect of vitamin D on worsening insulin resistance and secretion, thus augmenting the risk of developing type 2 diabetes. However, doubt remains as to whether low vitamin D levels are causal or merely a marker of worse disease or worse health status. Interventional studies have provided conflicting and inconclusive results due to the different populations studies, dose and time frame of vitamin D supplementation. Further studies are required.
Calcium ; Diabetes Mellitus ; Diabetes Mellitus, Type 2 ; Insulin Resistance ; Metabolism ; Obesity ; Risk Factors ; Vitamin D Deficiency ; Vitamin D* ; 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

Cardiovascular Diseases ; physiopathology ; Humans ; Inflammatory Bowel Diseases ; metabolism ; Kidney Diseases ; metabolism ; Neoplasms ; Vitamin D ; pharmacology ; physiology

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

OBJECTIVE: To assess the effect of vitamin K2 in addition to risedronate on postmenopausal osteoporosis METHOD: We enrolled 21 postmenopausal osteoporosis women (age: 65.2+/-7.8 years). Ten subjects received risedronate (35 mg, weekly) and vitamin K2 (45 mg, daily) and eleven subjects only received risedronate. They all received calcium citrate 2,130 mg and vitamin D 600 IU daily. The duration of treatment was 7.7+/-1.4 months. Bone mineral density (BMD) of lumbar spine and both femurs, serum osteocalcin and urine deoxypyridinoline were examined at baseline and after treatment. RESULTS: After treatment, BMD, serum osteocalcin and urine deoxypyridinoline were improved in each group but there was no statistical difference between the groups. CONCLUSION: There was no evidence of the benefit of vitamin K2 in addition to risedronate in bone metabolism on postmenopausal osteoporosis.
Bone Density ; Calcium Citrate ; Female ; Femur ; Humans ; Metabolism ; Osteocalcin ; Osteoporosis, Postmenopausal* ; Risedronate Sodium ; Spine ; Vitamin D ; Vitamin K 2* ; Vitamins*