Low vitamin D levels correlate with the proinflammatory state in type 1 diabetic subjects with and without microvascular complications

Am J Clin Pathol. 2011 Mar;135(3):429-33. doi: 10.1309/AJCPJGZQX42BIAXL.

Abstract

Epidemiologic studies link vitamin D deficiency to onset of type 1 diabetes mellitus (T1DM). T1DM exhibits increased inflammation, which is pronounced with microvascular complications (T1DM-MV). However, there are a paucity of data on vitamin D in T1DM-MV in relation to biomarkers of inflammation, and this formed the aim of the study. Healthy control subjects (n = 36), patients with T1DM (n = 24), and patients with T1DM-MV (n =26) were recruited. Serum vitamin D levels, monocyte toll-like receptor (TLR) 2 and TLR4 expression and nuclear factor-κB (NFκB) activity were assessed. Patients with T1DM and T1DM-MV were significantly vitamin D deficient compared with control subjects (P < .01). There was a significant negative correlation between vitamin D levels and high-sensitivity C-reactive protein, NFκB activity, and TLR4 expression (P < .05). Preincubation with vitamin D significantly decreased lipopolysaccharide-activated TLR4 expression and cytokine levels in monocytes (P < .05). Low vitamin D levels may contribute to increased inflammation in T1DM. Future studies will elucidate the immunomodulatory effects of vitamin D in decreasing vascular risk in this population.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • C-Reactive Protein / metabolism
  • Diabetes Mellitus, Type 1 / complications
  • Diabetes Mellitus, Type 1 / metabolism*
  • Diabetes Mellitus, Type 1 / pathology
  • Diabetic Angiopathies / complications
  • Diabetic Angiopathies / metabolism*
  • Diabetic Angiopathies / pathology
  • Female
  • Humans
  • Inflammation / complications
  • Inflammation / metabolism*
  • Inflammation / pathology
  • Male
  • Microvessels / pathology
  • Monocytes / metabolism
  • Monocytes / pathology
  • Protein-Serine-Threonine Kinases / metabolism
  • Toll-Like Receptor 2 / metabolism
  • Toll-Like Receptor 4 / metabolism
  • Vitamin D Deficiency / complications
  • Vitamin D Deficiency / metabolism*
  • Vitamin D Deficiency / pathology

Substances

  • TLR2 protein, human
  • TLR4 protein, human
  • Toll-Like Receptor 2
  • Toll-Like Receptor 4
  • C-Reactive Protein
  • Protein-Serine-Threonine Kinases
  • NF-kappa B kinase