Analysis of Microsomal Reductase Activity in Ovarian Tissue After Cryopreservation by Enhanced Chemiluminescence

Abstract

The aim of the study was to investigate the activity of NADH-dependent cytochrome b5 reductase (CYB5R) and NADPH-dependent cytochrome P450 reductase (CYPOR) in ovarian tissues after cryopreservation by lucigenin-enhanced chemiluminescence with NADH and NADPH stimulation, respectively. The results indicate that both mitochondrial and microsomal reductase activities are preserved in cryopreserved ovarian tissues. After cryopreservation, the level of production of superoxide anion radical by mitochondria drops by 3–10 times, while the presence or absence of chemotherapy has no effect, and this parameter is also not affected by the severity of the disease. Compared to the control group (patients with benign tumors), the activity of CYB5R and CYPOR of ovarian tissue in a malignant cancer process decreases 1.5–10 times depending on the disease severity, and the presence of chemotherapy dramatically affects these parameters — the activity of microsomal reductases decreases by 50–100 times in chemotherapy compared to the control group. Thus, microsomal reductase activity is a more informative parameter for assessing the functionality of cryopreserved ovarian tissue than superoxide-producing capacity of mitochondria, because, firstly, it depends on the stage of disease and prior chemotherapy, and secondly, the analytical signal of NADH/NADPH stimulated chemiluminescence is characterized by approximately 30 times higher intensity than mitochondrial chemiluminescence, which leads to higher analytical sensitivity of the technique.