| Abstract
Objective
To assess the effects of dietary vitamin D3on proinflammatory (interleukin-17A [IL-17A] and
IL-6) and anti-inflammatory (IL-10) cytokines.
Methods
Our study was conducted on 75 participants who were divided into 3 groups: multiple sclerosis
participants (MSPs, n = 25),first-degree relative participants (FDRPs, n = 25), and healthy
participants (HPs, n = 25). All groups received 50,000 IU vitamin D3/wk for 8 weeks. Serum
25-(OH) vitamin D3
levels and messenger RNA (mRNA) expression levels of ILs were determined using electrochemiluminescence assay and real-time PCR, respectively.
Results
Vitamin D3affected the levels of IL-17A, IL-10, and IL-6 among the 3 groups (p< 0.001 for all).
Levels of IL-17A (MSPs: fold change [FC] = 5.9,p= 0.014; FDRPs: FC = 5.2,p= 0.006; HPs:
FC = 4.2,p= 0.012) and IL-6 (MSPs: FC = 5.6,p= 0.003; FDRPs: FC = 5.5,p= 0.002; HPs:
FC = 5.1,p< 0.001) were downregulated after vitamin D3treatment. In addition, levels of IL-10
(MSPs: FC = 6.2,p= 0.005; FDRPs: FC = 4.6,p< 0.001; HPs: FC = 5.2,p< 0.001) were
upregulated after 8 weeks.
Conclusions
Although supplementation with vitamin D3reduced the mRNA expression levels of IL-17A and
IL-6, it increased the mRNA expression level of IL-10 in all groups. However, these effects were
more considerable in the MSP group than in the other groups. Of interest, in a deficiency state
of serum vitamin D3, IL-17A expression had a positive feedback effect on the expression of IL-6.
Conversely, in the sufficient state, IL-10 expression had a negative feedback effect on the
expression of IL-17A and IL-6. |