2.4. Blood Collection

10 mL of venous blood was collected using the S-Monovette® K3 EDTA blood collection system (Sarstedt). All samples were taken on an empty stomach after an overnight rest. Blood was centrifuged (10 min, +4°C, 1500 × g), and plasma (upper layer after centrifugation) was collected immediately. Erythrocytes (bottom layer) were rinsed three times with cold saline (0.9% NaCl) and then hemolyzed by adding 9 volumes of cold 50 mM phosphate buffer, pH 7.4 (1 : 9, v/v) [11, 15]. No hemolysis was observed in any of the collected samples. Similarly to NWS and SWS, an antioxidant (10 μL of 0.5 M butylated hydroxytoluene for 1 mL of blood) was added [11, 15]. Samples were frozen at -80°C until assayed.