Serum IL-18 and hsCRP correlate with insulin resistance without effect of calcitriol treatment on type 2 diabetes.
BACKGROUND
Chronic low-grade systemic inflammation presented in Type 2 diabetes mellitus plays a major role in disease progression as well as development of micro- and macro-vascular complications of diabetes. Therefore, reducing inflammation can be beneficial in prevention of diabetes complications.


OBJECTIVE
To investigate the association between insulin resistance and inflammatory markers, and assessing the effects of oral Calcitriol on inflammatory cytokines in type 2 diabetic patients.


METHODS
In this double-blind randomized placebo-controlled trial, 70 participants with type-2 diabetes were randomly divided to two groups. One group received two capsules of Calcitriol (0.25 μg 1,25-dihydroxy cholecalciferol per each capsule) per day. The second group received placebo tablets. At the beginning of the study, we assessed insulin resistance and its relation to inflammatory profile. Serum high sensitive C-reactive protein (hs CRP), interleukin-6 and interleukin-18 were also measured at the beginning and the end of the 12-week supplementation trial.


RESULTS
Mean calcium, phosphorus and vitamin D concentrations in the study participants were 8.98 ± 0.79 mg/dL, 3.86 ± 0.50 mg/dL and 40.91 ± 30.9 ng/mL, respectively. IL-18 and hsCRP had significant positive associations with insulin resistance markers and negative associations with insulin sensitivity markers. At the end of the 12-week supplementation trial, no significant difference was seen in serum levels of hsCRP, IL-6 and IL-18 between the two groups, while these values were adjusted for baseline values.


CONCLUSIONS
Inflammation was associated with insulin resistance in diabetic patients. No anti-inflammatory effect of Calcitriol in terms of decreasing hsCRP, IL-6 and IL-18 detected.
Department of Nutrition, School of Health and Nutrition, Shiraz University of Medical Sciences, Shiraz, Iran, e-mail: marzieh_akbarzadeh@yahoo.com.
Marzieh
M
Akbarzadeh
Mohammad Hassan
MH
Eftekhari
Mohammad Hossein
MH
Dabbaghmanesh
Jafar
J
Hasanzadeh
Marzieh
M
Bakhshayeshkaram
D000328:Adult; D000368:Aged; D002097:C-Reactive Protein / Q000032:analysis*; D002117:Calcitriol / Q000008:administration & dosage*; D002118:Calcium / Q000378:metabolism; D002120:Calcium Channel Agonists / Q000008:administration & dosage*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000188:drug therapy*; D005260:Female; D006801:Humans; D007333:Insulin Resistance / Q000276:immunology; D015850:Interleukin-6 / Q000097:blood; D016209:Interleukin-8 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome; D014807:Vitamin D / Q000378:metabolism
C508606:CXCL8 protein, human; D002120:Calcium Channel Agonists; D015850:Interleukin-6; D016209:Interleukin-8; D014807:Vitamin D; D002097:C-Reactive Protein; D002117:Calcitriol; D002118:Calcium