Biochemical analyses
Number:1,500,017
BLOOD, INSULIN RESISTANCE
At the baseline and end of the study, a 10 mL venous blood sample was taken from all participants after 12 h of fasting. Blood sampling was performed between 8:00 AM and 9:00 AM during the early follicular phase (days 2 to 5) of a spontaneous menstrual cycle or P-induced menstrual cycle. Blood samples were immediately centrifuged at a speed of 3500 rpm for ten minutes, and serum samples were separated from whole blood and directly frozen at -80 °C until examination time. Oxidant and antioxidant parameters, including CAT (Teb Pazhouhan Razi Co., Catalog Number: TPR-CAT-96T, Tehran, Iran. Intra and inter-assay coefficient of variation (CV) 4.1% and 9.9% respectively), TAC (Teb Pazhouhan Razi Co., Catalog Number: TPR-TAC-96T, Tehran, Iran. Intra and inter-assay CVs 5.7% and 3.7% respectively), and MDA (Teb Pazhouhan Razi Co., Catalog Number: TPR-MDA-96T, Tehran, Iran. Intra and inter-assay CVs 6.7% and 7.2% respectively), were measured using enzyme-linked immunosorbent assay (ELISA) kit and based on the manufacturer’s instructions. The serum fasting blood sugar (FBS) was measured adopting enzymatic methods and colorimetric technique and using commercial kits (Pars Azmoon, Catalog Number:1,500,017, Karaj, Iran. Intra- and inter-assay CVs were 1.63 and 2.2 respectively) with an auto-analyzer (Hitachi-917, Tokyo, Japan). Furthermore, serum insulin level (Monobind, Inc.,Catalog Number: 2,425,300, Lake Forest, CA, USA. Intra and inter-assay CVs < 5.6% both) was determined by performing chemiluminescence (IMMULITE 2000, SIEMENS), and the homeostatic model of assessment for insulin resistance (HOMA-IR) was calculated using the suggested formula [