Division of Pediatric Allergy and Immunology, National Jewish Health, Denver, CO, USA.
J Allergy Clin Immunol. 2012 May;129(5):1243-51. doi: 10.1016/j.jaci.2012.01.044. Epub 2012 Feb 11.
The effects of serum vitamin D status on atopy, steroid requirement, and functional responsiveness to corticosteroids in children versus adults with asthma have not been studied systematically.
We sought to explore the age-specific effects of vitamin D in asthmatic patients.
Serum vitamin D levels were examined in a prospective study of adults and children (102 healthy control subjects and 103 asthmatic patients). PBMCs were cultured for 3 hours with or without 100 nmol/L dexamethasone, and the expression of corticosteroid-regulated genes was detected by using real-time PCR. Serum IgE levels were measured, and information about asthmatic patients' steroid requirements was collected.
Deficient serum vitamin D levels (<20 ng/mL) were found in 47.6% of asthmatic patients and 56.8% of healthy control subjects, with means ± SDs of 20.7 ± 9.8 and 19.2 ± 7.7 ng/mL, respectively. In multivariate regression models a significant positive correlation between serum vitamin D levels and the expression of vitamin D-regulated targets, cytochrome P450, family 24, subfamily a (cyp24a) expression by PBMCs (P = .0084, pediatric asthma group only) and serum LL-37 levels (P = .0006 in the pediatric group but P = .0067 in the adult asthma group), was found. An inverse association between vitamin D and serum IgE levels was observed in the pediatric (P = .006) asthma group. Serum vitamin D level (P = .05), as well as PBMC cyp24a expression (P = .0312), demonstrated a significant inverse relationship with daily inhaled corticosteroid dose in the pediatric asthma group only. Cyp24a expression in PBMCs correlated positively with in vitro suppression of TNF-α by dexamethasone (P = .05) and IL-13 (P = .0094) in PBMCs in the pediatric asthma group only.
This study demonstrated significant associations between serum vitamin D status and steroid requirement and in vitro responsiveness to corticosteroids in the pediatric but not the adult asthma group. Vitamin D was also related to IgE levels in children but not in adults.
血清维生素 D 状态对儿童和成人哮喘患者的特应性、类固醇需求和对皮质类固醇的功能反应的影响尚未被系统研究。
我们旨在探讨维生素 D 在哮喘患者中的年龄特异性作用。
对成人和儿童（102 名健康对照者和 103 例哮喘患者）进行前瞻性研究，检测血清维生素 D 水平。用或不用 100nmol/L 地塞米松培养 PBMC3 小时，并通过实时 PCR 检测糖皮质激素调节基因的表达。测量血清 IgE 水平，并收集哮喘患者类固醇需求的信息。
47.6%的哮喘患者和 56.8%的健康对照者存在血清维生素 D 水平不足（<20ng/mL），其均值±SD 分别为 20.7±9.8ng/mL 和 19.2±7.7ng/mL。在多元回归模型中，血清维生素 D 水平与 PBMC 中环氧化酶 P450 家族 24 亚家族 A（cyp24a）表达（P=0.0084，仅儿科哮喘组）和血清 LL-37 水平（P=0.0006，仅儿科组，但 P=0.0067，成人哮喘组）呈显著正相关。在儿科哮喘组中，观察到维生素 D 与血清 IgE 水平之间呈负相关（P=0.006）。仅在儿科哮喘组中，血清维生素 D 水平（P=0.05）和 PBMC cyp24a 表达（P=0.0312）与每日吸入皮质类固醇剂量呈显著负相关。仅在儿科哮喘组中，PBMC 中环氧化酶 P450 家族 24 亚家族 A（cyp24a）表达与地塞米松体外抑制 TNF-α（P=0.05）和白细胞介素 13（P=0.0094）呈正相关。
本研究表明，血清维生素 D 状态与儿童而非成人哮喘患者的类固醇需求和对皮质类固醇的体外反应性之间存在显著关联。维生素 D 还与儿童的 IgE 水平有关，但与成人无关。
