Markers of inflammation and oxidative stress
Serum IL-6 concentrations were measured using Luminex immunoassay. Monocyte chemoattractant protein 1 levels were measured using a commercial kit (Linco Research, St. Charles, MO) according to the manufacturer instructions. Soluble CD40 ligand concentrations were measured in plasma using an ELISA kit (Quantikin, R&D Systems, Minneapolis, MN). We measured these inflammatory markers in our previous study [5]. F2-isoprostanes, which is a stable and reliable marker of lipid peroxidation, were measured in plasma using ion gas-chromatophragy mass spectroscopy (GC/MS), as previously described