Myeloperoxidase duoset elisa

Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) and xanthine oxidase (XO) activities were determined in plasma, as previously described [33 (link)] by the reaction of NTB with superoxide produced by hypoxanthine or NADPH with XO and NOX, respectively. NOX and XO activities were calculated by measuring spectrophotometrically the kinetic appearance of the complex formed by superoxide and NTB at 560 nm for 10 min.
Myeloperoxidase concentration was evaluated in plasma samples using a commercial ELISA kit (Myeloperoxidase DuoSet ELISA, R&D Systems, Minneapolis, MN, USA). The optical density was determined at 450 nm. The intra-assay CV was 2.9%.

Plasma myeloperoxidase (MPO) concentrations were measured using a commercial ELISA kit (Myeloperoxidase DuoSet ELISA, R&D Systems, Minneapolis, MN, USA). Triglycerides were measured in hepatic samples using a commercial kit (Cayman Chemical, Ann Arbor, MI, USA). Plasma lipopolysaccharide (LPS) activity was evaluated in HEK-Blue-mTLR4 cells (Invivogen, San Diego, CA, USA). Briefly, 180 µL of cell suspension (1.4 × 10⁴ cells per mL of HEK-Blue Detection medium) (Invivogen, San Diego, CA, USA) was added to 20 µL of each diluted (1:1000) plasma sample. LPS (Invivogen, San Diego, CA, USA) was used as positive control and standard range. Plates were incubated at 37 °C in 5% CO₂ for 24 h, and alkaline phosphatase activity was measured at 620 nm.

Advanced oxidation protein products (AOPP) were determined in plasma, liver, gastrocnemius and epididymal adipose tissue samples, as described by [27 (link)]. Oxidized Low-Density Lipoproteins (oxLDL) were measured in plasma using an ELISA kit (Elabscience^®, Houston, TX, USA) according to the manufacturers’ recommendations. SuperOxide Dismutase (SOD), Glutathione Peroxidase (GPx) and catalase activities were determined in plasma, liver, muscle and epididymal adipose tissue, as described by Groussard et al. [27 (link)].
Plasma myeloperoxidase (MPO) concentration was measured using a commercial ELISA kit (Myeloperoxidase DuoSet ELISA, R&D Systems, Minneapolis, MN, USA).
Plasma lipopolysaccharide binding protein (LBP) was quantified with the LBP ELISA Kit for various species (Hycult Biotech, Frontstraat, Uden, The Netherlands), following the manufacturer’s instructions.