ABSTRACT

Bronchial Asthma is outlined as a chronic irritation of the airways in children. Vitamin D is a real immune system regulator which has a potential part in allergy. Asymmetric Dimethyl Arginine (ADMA) is an endogenic Nitric Oxide Synthase (NOS) inhibitor. This study is to determine if there is a role of vitamin D deficiency, ADMA in the pathogenesis of asthma in children, And whether the decreased arginine bioavailability and NOS suppression by ADMA contribute to respiratory tract blockage or not. We measured serum vitamin D, ADMA, nitric oxide and plasma L-arginine in 30 asthmatic and 10 healthy children. Serum 25-hydroxy vitamin D, plasma L-Arginine and serum Nitric Oxide were decreased significantly in asthmatic patients compared to healthy children. On the other hand, ADMA serum levels were increased significantly in asthmatic patients. In asthmatic children, there were positive correlations between serum vitamin D concentration and forced expiratory volume in the first, second FEV1 (%predicted). Furthermore, there were negative correlations between serum ADMA concentration and FEV1 (%predicted). In conclusion, marked reduction of vitamin D and elevated ADMA serum levels in asthmatic children has contributed to NOS-related pathophysiology, therefore ADMA and vitamin D could be considered reliable in managing oxidative stress in asthma.

摘要

支气管哮喘被概述为儿童气道的慢性刺激。维生素 D 是一种真正的免疫系统调节剂，可能会导致过敏。不对称二甲基精氨酸 (ADMA) 是一种内源性一氧化氮合酶 (NOS) 抑制剂。本研究旨在确定维生素 D 缺乏、ADMA 在儿童哮喘发病机制中是否存在作用，以及 ADMA 引起的精氨酸生物利用度降低和 NOS 抑制是否有助于呼吸道阻塞。我们测量了 30 名哮喘儿童和 10 名健康儿童的血清维生素 D、ADMA、一氧化氮和血浆 L-精氨酸。与健康儿童相比，哮喘患者的血清 25-羟基维生素 D、血浆 L-精氨酸和血清一氧化氮显着降低。另一方面，哮喘患者的 ADMA 血清水平显着升高。在哮喘儿童中，血清维生素 D 浓度与第一次、第二次 FEV1（预测百分比）的用力呼气量呈正相关。此外，血清 ADMA 浓度与 FEV1（预测百分比）之间存在负相关。总之，哮喘儿童维生素 D 的显着减少和 ADMA 血清水平升高促成了 NOS 相关的病理生理学，因此 ADMA 和维生素 D 可被认为是控制哮喘氧化应激的可靠方法。