Ogunsakin Olalekan, Hottor Tete, Mehta Ashish, Lichtveld Maureen, McCaskill Michael
Department of Global Environmental Health Sciences, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA.
Emory University School of Medicine, Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Atlanta, GA, USA.; Atlanta VA Medical Center, Atlanta, GA, USA.
Environ Health Insights. 2016 Oct 20;10:191-199. doi: 10.4137/EHI.S40335. eCollection 2016.
Vitamin D has been previously recognized to play important roles in human immune system and function. In the pulmonary system, vitamin D regulates the function of antimicrobial peptides, especially cathelicidin/LL-37. Human cathelicidin/LL-37 is a bactericidal, bacteriostatic, and antiviral endogenous peptide with protective immune functions. Chronic exposure to excessive alcohol has the potential to reduce levels of vitamin D (inactive vitamin D [25(OH)D] and active vitamin D [1, 25(OH)D]) and leads to downregulation of cathelicidin/LL-37. Alcohol-mediated reduction of LL-37 may be partly responsible for increased incidence of more frequent and severe respiratory infections among subjects with alcohol use disorder (AUD). The objective of this study was to investigate the mechanisms by which alcohol exerts its influence on vitamin D metabolism. In addition, the aim was to establish associations between chronic alcohol exposures, levels of pulmonary vitamin D, and cathelicidin/LL-37 using broncho-alveolar lavage fluid samples of subjects with AUD and healthy controls. Findings from the experiment showed that levels of inactive vitamin D (25(OH)D), active vitamin D (1, 25(OH)D), cathelicidin/LL-37, and CYP27B1 proteins were significantly reduced ( < 0.05) when compared with the matched healthy control group. However, CYP2E1 was elevated in all the samples examined. Chronic exposure to alcohol has the potential to reduce the levels of pulmonary vitamin D and results in subsequent downregulation of the antimicrobial peptide, LL-37, in the human pulmonary system.
维生素D此前已被认为在人体免疫系统和功能中发挥重要作用。在肺部系统中，维生素D调节抗菌肽的功能，尤其是cathelicidin/LL-37。人cathelicidin/LL-37是一种具有保护性免疫功能的杀菌、抑菌和抗病毒内源性肽。长期过量饮酒有可能降低维生素D（无活性维生素D [25(OH)D] 和活性维生素D [1, 25(OH)D]）的水平，并导致cathelicidin/LL-37的下调。酒精介导的LL-37减少可能部分导致酒精使用障碍（AUD）患者中更频繁和严重的呼吸道感染发病率增加。本研究的目的是调查酒精对维生素D代谢产生影响的机制。此外，目的是利用AUD患者和健康对照者的支气管肺泡灌洗液体样本，建立慢性酒精暴露、肺部维生素D水平和cathelicidin/LL-37之间的关联。实验结果表明，与匹配的健康对照组相比，无活性维生素D（25(OH)D）、活性维生素D（1, 25(OH)D）、cathelicidin/LL-37和CYP27B1蛋白的水平显著降低（<0.05）。然而，在所有检测样本中CYP2E1均升高。长期接触酒精有可能降低肺部维生素D水平，并导致人体肺部系统中抗菌肽LL-37随后下调。
