Title:Interplay of Immunity and Vitamin D: Interactions and Implications with Current IBD Therapy
VOLUME: 24 ISSUE: 9
Author(s):Joe Abdo, Vikrant Rai and Devendra K. Agrawal*
Affiliation:Department of Clinical and Translational Science, Creighton University School of Medicine, Omaha, NE 68178, Department of Clinical and Translational Science, Creighton University School of Medicine, Omaha, NE 68178, Department of Clinical & Translational Science, The Peekie Nash Carpenter Endowed Chair in Medicine, Clinical & Translational Research, CRISS II Room 510, 2500 California Plaza, Omaha, NE, 68178
Keywords:Vitamin D, inflammatory bowel disease, biologics, anti-inflammatory therapy, immune suppressors,
microbial invasion, human defensins, intestinal health, Crohn’s disease, ulcerative colitis.
Abstract:Crohn's disease (CD) and ulcerative colitis (UC) are classified under inflammatory
bowel disease (IBD) which has been linked to a multifaceted etiology involving both environmental
and genetic factors that intersect with the vitamin D pathway. Dysfunctions in innate
immune defense mechanisms in the epithelial compartment of the intestine play a crucial
role in the pathogenesis of IBD. Symptoms of IBD are caused by excessive immune responses
to luminal bacteria, and vitamin D has been shown to play a role in intestinal defense by aiding
in the suppression of microbial invasion into the epithelium. Vitamin D, as an immunomodulator,
can modify the innate immune response of the body. Vitamin D attenuates the transcription
of pro-inflammatory cytokines that are upregulated in the event of epithelial stress
common in patients with IBD. Vitamin D deficiency was identified in 82% of IBD patients
compared to the 31% national average and has been linked to defective epithelial processes at
both genomic and proteomic levels. Mucosal damage and an impaired immune response are at
the center of IBD, and vitamin D aids in sustaining the structural integrity of epithelial cells
while enhancing innate immune responses in the mucosa. Here we provide a systematic
review of the pathophysiological effects of cytokines in IBD in the presence of vitamin D
deficiency. Also, analysis of the immunomodulatory effect of vitamin D in regulating
immunopathogenic factors like chemokines, growth factors, and human defensins will
enhance knowledge of the underlying molecular mechanisms of the therapeutic role of vitamin
D in IBD and thus aid in the development of better patient management strategies.
