title: Vitamin D, serum 25(OH)D, LL-37 and polymorphisms in a Canadian First Nation population with endemic tuberculosis.
abstract: BACKGROUND
  Canadian First Nation populations have experienced endemic and epidemic tuberculosis (TB) for decades. Vitamin D-mediated induction of the host defence peptide LL-37 is known to enhance control of pathogens such as Mycobacterium tuberculosis.
  
  
  OBJECTIVE
  Evaluate associations between serum levels of 25-hydroxy vitamin D (25(OH)D) and LL-37, in adult Dene First Nation participants (N = 34) and assess correlations with single nucleotide polymorphisms (SNPs) in the vitamin D receptor (VDR) and vitamin D binding protein (VDBP).
  
  
  METHODS
  Venous blood was collected from all participants at baseline (winter and summer) and in conjunction with taking vitamin D supplements (1,000 IU/day) (winter and summer). Samples were analysed using ELISA for concentrations of vitamin D and LL-37, and SNPs in the VDR and VDBP regions were genotyped.
  
  
  RESULTS
  Circulating levels of 25(OH)D were not altered by vitamin D supplementation, but LL-37 levels were significantly decreased. VDBP and VDR SNPs did not correlate with serum concentrations of 25(OH)D, but LL-37 levels significantly decreased in individuals with VDBP D432E T/G and T/T, and with VDR SNP Bsm1 T/T genotypes.
  
  
  CONCLUSIONS
  Our findings suggest that vitamin D supplementation may not be beneficial as an intervention to boost innate immune resistance to M. tuberculosis in the Dene population.
authors: Department of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada.|Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada.|Department of Community Health Sciences, University of Manitoba, Winnipeg, MB, Canada; llarcombe@hsc.mb.ca.
authors: Linda
authors: L
authors: Larcombe
authors: Department of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada.|Manitoba Centre for Proteomics and Systems Biology, University of Manitoba, Winnipeg, MB, Canada.
authors: Neeloffer
authors: N
authors: Mookherjee
authors: Department of Human Nutritional Sciences, University of Manitoba, Winnipeg, MB, Canada.
authors: Joyce
authors: J
authors: Slater
authors: Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada.
authors: Caroline
authors: C
authors: Slivinski
authors: Northlands Denesuline First Nation, Lac Brochet, MB, Canada.
authors: Joe
authors: J
authors: Dantouze
authors: Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada.
authors: Matthew
authors: M
authors: Singer
authors: Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada.
authors: Chris
authors: C
authors: Whaley
authors: Northlands Denesuline First Nation, Lac Brochet, MB, Canada.
authors: Lizette
authors: L
authors: Denechezhe
authors: Department of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada.
authors: Sara
authors: S
authors: Matyas
authors: Department of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada.
authors: Kate
authors: K
authors: Decter
authors: Department of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada.
authors: Emily
authors: E
authors: Turner-Brannen
authors: Department of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada.|Department of Community Health Sciences, University of Manitoba, Winnipeg, MB, Canada.
authors: Clare
authors: C
authors: Ramsey
authors: Department of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada.|Manitoba Centre for Proteomics and Systems Biology, University of Manitoba, Winnipeg, MB, Canada.
authors: Peter
authors: P
authors: Nickerson
authors: Department of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada.|Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada.|Department of Community Health Sciences, University of Manitoba, Winnipeg, MB, Canada.
authors: Pamela
authors: P
authors: Orr
mesh_terms: D000328:Adult; D023181:Antimicrobial Cationic Peptides / Q000235:genetics*; D002170:Canada / Q000453:epidemiology; D015331:Cohort Studies; D019353:Endemic Diseases; D005260:Female; D005819:Genetic Markers; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D044382:Population Groups; D011446:Prospective Studies; D018167:Receptors, Calcitriol / Q000235:genetics*; D018570:Risk Assessment; D014376:Tuberculosis / Q000097:blood / Q000188:drug therapy / Q000453:epidemiology* / Q000235:genetics; D014807:Vitamin D / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood; D014809:Vitamin D-Binding Protein / Q000235:genetics*; D054804:Cathelicidins
chemical_list: D023181:Antimicrobial Cationic Peptides; D005819:Genetic Markers; D018167:Receptors, Calcitriol; D014809:Vitamin D-Binding Protein; D014807:Vitamin D; C104450:25-hydroxyvitamin D; D054804:Cathelicidins
keywords: cathelicidin (LL-37); genetics; indigenous; tuberculosis; vitamin D