title: Vitamin D deficiency is associated with an oxidized plasma cysteine redox potential in critically Ill children.
abstract: Critically ill populations incur high levels of oxidative stress and commonly present with vitamin D deficiency. This study aimed to investigate the relationship between vitamin D status and plasma markers of glutathione (GSH) and cysteine (Cys) redox and immunity in critically ill children. This was a cross-sectional study of n=50 PICU patients. Subjects were categorized according to their plasma 25-hydroxyvitamin D [25(OH)D] concentrations: (<20, 20-30, and ≥30ng/dL). Plasma GSH, glutathione disulfide (GSSG), Cys, and cystine (CySS) were measured with high-performance liquid chromatography, and their associated redox potentials determined (EhGSSG and EhCySS, respectively). Plasma LL-37, an indicator of innate immune function, was assayed with ELISA. Data were analyzed using general linear regression before and after adjustment for age, sex, and race. Results showed that EhCySS was more reduced in subjects with plasma 25(OH)D concentrations ≥30ng/mL compared to those with 25(OH)D concentrations <20ng/mL (P=0.009). Plasma GSH, GSSG, and total GSH decreased with increasing 25(OH)D category (P=0.06, 0.03, and 0.01, respectively), and plasma glutamine levels were lowest in subjects with plasma 25(OH)D concentrations ≥30ng/mL (P=0.004). Plasma LL-37 concentrations did not significantly differ by vitamin D status (P=0.08). In conclusion, vitamin D sufficiency was associated with more reduced plasma EhCySS, indicative of lower oxidative stress in critically ill children. Plasma GSH, GSSG, and glutamine, however, were lower in the vitamin D sufficient group. The role of vitamin D in maintaining redox status during pediatric critical illness requires further study.
authors.affiliation: Emory University School of Medicine, Department of Medicine, Division of Endocrinology, Metabolism & Lipids, Atlanta, GA, United States; Emory + Children's Pediatric Research Center, Atlanta, GA, United States. Electronic address: jessica.alvarez@emory.edu.
authors.forename: Jessica A
authors.initials: JA
authors.lastname: Alvarez
authors.affiliation: Emory University School of Medicine, Department of Pediatrics, Division of Pediatric Critical Care Medicine, Atlanta, GA, United States; Children's Healthcare of Atlanta at Egleston, Atlanta, GA, United States.
authors.forename: Jocelyn R
authors.initials: JR
authors.lastname: Grunwell
authors.affiliation: Emory + Children's Pediatric Research Center, Atlanta, GA, United States; Emory University School of Medicine, Department of Pediatrics, Division of Infectious Disease; Emory + Children's Pediatric Research Center, Atlanta, GA, United States, United States.
authors.forename: Scott E
authors.initials: SE
authors.lastname: Gillespie
authors.affiliation: Emory University School of Medicine, Department of Medicine, Division of Endocrinology, Metabolism & Lipids, Atlanta, GA, United States; Emory + Children's Pediatric Research Center, Atlanta, GA, United States; Atlanta Veterans Affairs Medical Center, Section of Endocrinology, Atlanta, GA, United States.
authors.forename: Vin
authors.initials: V
authors.lastname: Tangpricha
authors.affiliation: Emory + Children's Pediatric Research Center, Atlanta, GA, United States; Emory University School of Medicine, Department of Pediatrics, Division of Pediatric Critical Care Medicine, Atlanta, GA, United States; Children's Healthcare of Atlanta at Egleston, Atlanta, GA, United States.
authors.forename: Kiran B
authors.initials: KB
authors.lastname: Hebbar
mesh_terms: D000293:Adolescent; D001741:Black or African American; D023181:Antimicrobial Cationic Peptides / Q000097:blood / Q000276:immunology; D002648:Child; D016638:Critical Illness; D003430:Cross-Sectional Studies; D003545:Cysteine / Q000097:blood*; D005260:Female; D005978:Glutathione / Q000097:blood*; D006801:Humans; D007113:Immunity, Innate; D008297:Male; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D012772:Shock, Septic / Q000097:blood* / Q000150:complications / Q000208:ethnology / Q000276:immunology; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood* / Q000150:complications / Q000208:ethnology / Q000276:immunology; D044465:White People; D054804:Cathelicidins
chemical_list: D023181:Antimicrobial Cationic Peptides; D014807:Vitamin D; C104450:25-hydroxyvitamin D; D005978:Glutathione; D003545:Cysteine; D054804:Cathelicidins
keywords: Calcidiol; Cathelicidin; Critical care; LL-37; Oxidative stress; Pediatrics