Carbon monoxide refines ovarian structure changes and attenuates oxidative stress via modulating of heme oxygenase system in a rat model of polycystic ovary syndrome: An experimental study

Background: Carbon monoxide (CO), influences ovarian function, pregnancy, and placental health. Heme oxygenase (HO)-1 and its products, including CO, exhibit protective and anti-inflammatory properties. Objective: This study investigate the protective effects of CO released by the carbon dioxide-releasing molecule (CORM)-2 against oxidative stress, functional and structural changes of the ovaries, and HO-1 expressions in female rats suffering from polycystic ovary syndrome (PCOS). Materials and Methods: In this experimental study, 24 Rattus norvegicus var. Albinus female rats (180-200 gr, 8 wk) were randomly divided into 4 groups (n = 6/each): control, CORM-2 (10 mg/kg), PCOS (induced by 4 mg/kg, intramuscular injection and a single dose of estradiol valerate), PCOS + CORM-2. Ovary histological changes were evaluated by crystal violet staining. Malondialdehyde (MDA) level and superoxide dismutase (SOD) activity of ovarian tissue were assessed using enzyme-linked immunosorbent assay. HO-1 expression was evaluated using Western blot. Results: Corpus luteal formation significantly decreased in the PCOS group and was significantly restored with CORM-2 administration compared to the control group (p 0.05). The expression of ovarian HO-1 protein was reduced in the PCOS group compared to controls (p 0.01), and administration of CORM in PCOS rats significantly increased its expression (p 0.0001). In addition, CORM administration markedly reduced ovarian MDA levels and restored SOD activity (p 0.0001). Conclusion: CORM-2 administration to PCOS rats created protective effects by reducing oxidative stress (reducing MDA level and restoring SOD activity) and increasing ovarian HO-1 protein.