Association of self-reported symptoms with serum levels of vitamin D and multivariate cytokine profile in healthy women.

BACKGROUND: Although a large number of studies have investigated possible relationships among serum levels of vitamin D or cytokines with disease progress and prognosis, similar studies on self-reported symptoms are still controversial. The overall objective of this study was to look into the association between serum levels of vitamin D or cytokines with self-reported symptoms related to musculoskeletal pain, sleep disorders, and premenstrual syndrome (PMS) in healthy adult women. SUBJECTS AND METHODS: Venous blood samples were collected from 117 healthy adult women, and serum levels of vitamin D, pro-inflammatory cytokines (IL-1ß, IL-6, IL-8, IL-17, IFN-γ, and TNF-α) and anti-inflammatory cytokines (IL-4, IL-10, and IL-13) were measured. Groups were tested for differences in single parameters, pro-:anti-inflammatory cytokine ratios, and differences in multivariate patterns. RESULTS: There were no significant associations between serum levels of vitamin D and any of the self-reported symptoms studied. However, serum levels of certain pro-inflammatory cytokines were significantly higher in subjects with musculoskeletal pain (IL-8, P=0.008), sleep disorders (IFN-γ, P=0.02), and PMS (IL-8 and TNF-α, P=0.009 and 0.002, respectively) compared to subjects who reported no symptoms. The pro-:anti-inflammatory cytokine ratios showed pro-inflammatory cytokine dominance in subjects with self-reported symptoms, particularly in the groups with deficient levels of vitamin D. However, the multivariate cytokine-pattern analysis was significantly different between PMS groups only. CONCLUSION: These data point to a possible role of pro-inflammatory cytokines as a contributing factor in self-reported symptoms related to musculoskeletal pain, sleep disorders, and PMS.

Association between levels of vitamin D and inflammatory markers in healthy women.

BACKGROUND: No one can deny that the biological importance of vitamin D is much beyond its classical role in bone metabolism. Several recent publications have highlighted its potential role in the functioning of the immune system. The overall objective of this study was to look into possible correlations between levels of vitamin D and inflammatory markers in sera of healthy adult women. These markers included proinflammatory cytokines (interleukin [IL]-1ß, IL-6, IL-8, IL-17, interferon [IFN]-γ, and tumor necrosis factor [TNF]-α), anti-inflammatory cytokines (IL-4, IL-10, and IL-13), as well as C-reactive protein (CRP) as a general indicator of inflammation. METHODS: Venous blood samples were collected from 118 healthy adult women and serum levels of vitamin D, CRP, proinflammatory cytokines (IL-1ß, IL-6, IL-8, IL-17, IFN-γ, and TNF-α), and anti-inflammatory cytokines (IL-4, IL-10, and IL-13) were measured. RESULTS: There were no significant direct correlations between serum levels of vitamin D and any of the inflammatory markers measured. However, subjects with deficient levels of vitamin D and high CRP produced significantly higher levels of the proinflammatory cytokines (TNF-α and IL-8) as compared to subjects with low CRP levels with nondeficient and deficient levels of vitamin D. Further, the anti-inflammatory/proinflammatory ratios suggest a role of vitamin D in maintaining an anti-inflammatory environment at low levels of CRP, an association that is weaker at high CRP levels in subjects with subclinical inflammatory situations. CONCLUSION: These data point to a possible role of vitamin D as a contributing factor in balancing cytokines toward an anti-inflammatory role in inflammatory situations.