Association between circulating ascorbic acid, α-tocopherol, 25-hydroxyvitamin D, and plasma cytokine concentrations in young adults: a cross-sectional study

Abstract

BackgroundInflammation and oxidative stress are associated with the development of numerous chronic diseases. Circulating ascorbic acid, α-tocopherol, and 25-hydroxyvitamin D (25(OH)D) may help reduce concentrations of pro-inflammatory cytokines through their antioxidant and anti-inflammatory properties. These micronutrients may act synergistically, and they may have different anti-inflammatory effects, but previous studies have assessed the link between each of these micronutrients and inflammation in isolation without controlling for the other micronutrients. Our objective was to examine the association between circulating concentrations of ascorbic acid, α-tocopherol, and 25(OH) D and a panel of pro-inflammatory cytokines in an ethnically diverse population of young adults.MethodsParticipants (n = 1,007) from the Toronto Nutrigenomics and Health study provided fasting blood samples for biomarker measurements and were subsequently categorized into tertiles for each micronutrient based on their circulating concentrations. We conducted Pearson’s correlation analyses across all micronutrients and cytokines. The associations between individual micronutrients and cytokines were examined using analysis of covariance with age, sex, waist circumference, ethnicity, physical activity, season of blood collection, total cholesterol, hormonal contraceptive use among women, and the other two micronutrients as covariates.ResultsWe observed weak micronutrient-cytokine correlations, moderate correlations between certain cytokines, and strong correlations between specific cytokines, particularly interleukin 1- receptor antagonist (IL-1RA), interferon-γ (IFN-γ), and platelet-derived growth factor BB (PDGF-bb). After full covariate adjustment, circulating α-tocopherol was inversely associated with IFN-γ and regulated upon activation normal T-cell expressed and secreted (RANTES). We observed an unexpected positive association between ascorbic acid and IFN-γ. 25(OH)D was not associated with altered concentrations of any inflammatory biomarkers.ConclusionsThese findings suggest that α-tocopherol, but not ascorbic acid or 25(OH)D, is inversely associated with inflammation in healthy young adults.

Antioxidant and hepatoprotective activity of milk thistle (Silybum marianum L. Gaertn.) seed oil

“…Previous studies have recognized the antioxidant and anti-inflamatory properties of ascorbic acid, α-tocopherol [59] and sterols [60]. In our case, the histological and electron microscopy examination revealed that pretreatment with SMSO suppressed the acute hepatic damage and was consistent with the improvement of plasmatic and tissue biological parameters for hepatotoxicity.…”

Relationship between insulin resistance and plasma vitamin D in adults

“…As we indicated earlier, vitamin D deficiency may be linked to low-grade innate immunity-related chronic inflammatory responses6,20,21 known to be associated a range of chronic conditions (including insulin resistance) that predispose individuals to the development of T2DM at a later stage 6,21. As stated above, polymorphisms in CYP27B1 , vitamin D binding protein, and vitamin D receptors – that respectively mediate vitamin D synthesis, transport, and action – disrupt glucose homeostasis and the hormonal action of vitamin D 22–26.…”

A genetic variant in the cytochrome P450 family 2 subfamily R member 1 determines response to vitamin D supplementation

“…Emerging evidence has reported a relationship between vitamin D supplementation and serum levels of proinflammatory and inflammatory markers such as cytokines and CRP. Some studies have reported a positive association with circulation levels of 25(OH)D and others showed an inverse association while some declared no relationship [44][45][46][47].…”