ABSTRACT
Omega-3 (n-3) treatment may lower cardiovascular risk, yet its effects on the circulating lipidome and relation to cardiovascular risk biomarkers are unclear. We hypothesized that n-3 treatment is associated with favorable changes in downstream fatty acids (FAs), oxylipins, bioactive lipids, clinical lipid and inflammatory biomarkers. We examined these VITAL200, a nested substudy of 200 subjects balanced on demographics and treatment and randomly selected from the Vitamin D and Omega-3 Trial (VITAL). VITAL is a randomized double-blind trial of 840 mg/d eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) vs. placebo among 25,871 individuals. Small polar bioactive lipid features, oxylipins and FAs from plasma and red blood cells were measured using three independent assaying techniques at baseline and one year. The Women's Health Study (WHS) was used for replication with dietary n-3 intake. Randomized n-3 treatment led to changes in 143 FAs, oxylipins and bioactive lipids (False Discovery Rate (FDR) < 0.05 in VITAL200, validated (p-values < 0.05)) in WHS with increases in 95 including EPA, DHA, n-3 docosapentaenoic acid (DPA-n3), and decreases in 48 including DPA-n6, dihomo gamma linolenic (DGLA), adrenic and arachidonic acids. N-3 related changes in the bioactive lipidome were heterogeneously associated with changes in clinical lipid and inflammatory biomarkers. N-3 treatment significantly modulates the bioactive lipidome, which may contribute to its clinical benefits.
ABSTRACT
OBJECTIVE: To study the contribution of interferon-alpha (IFNalpha) and IFNgamma to the IFN gene expression signature that has been observed in microarray screens of peripheral blood mononuclear cells (PBMCs) from patients with systemic lupus erythematosus (SLE). METHODS: Quantitative real-time polymerase chain reaction analysis of healthy control PBMCs was used to determine the relative induction of a panel of IFN-inducible genes (IFIGs) by IFNalpha and IFNgamma. PBMCs from 77 SLE patients were compared with those from 22 disease controls and 28 healthy donors for expression of IFIGs. RESULTS: Expression of IFNalpha-inducible genes was significantly higher in SLE PBMCs than in those from disease controls or healthy donors. The level of expression of all IFIGs in PBMCs from SLE patients with IFNalpha pathway activation correlated highly with the inherent responsiveness of those genes to IFNalpha, suggesting coordinate activation of that cytokine pathway. Expression of genes preferentially induced by IFNgamma was not significantly increased in SLE PBMCs compared with control PBMCs. IFNalpha-regulated gene-inducing activity was detected in some SLE plasma samples. CONCLUSION: The coordinate activation of IFNalpha-induced genes is a characteristic of PBMCs from many SLE patients, supporting the hypothesis that IFNalpha is the predominant stimulus for IFIG expression in lupus.
