Investigation of the Effects of Silymarin on Ovarian Ischemia Reperfusion via Nrf-2/HO-1/NQO1, Ki-67 and Wnt Signaling Pathways

Ovarian ischemia is a pathological condition that usually occurs due to ovarian torsion, resulting in the interruption of blood supply to the ovaries and oxygen deficiency. Silymarin (SLM) is a flavonoid complex of plant origin with pharmacological properties such as antioxidant, anti-inflammatory, and antiapoptotic effects. In this study, we investigated the effects of SLM through different pathways in rats subjected to experimental ovarian ischemia/reperfusion (I/R). Female Wistar rats were divided into five groups: Control, SLM (50 mg/kg), I/R, I/R + SLM25 (25 mg/kg), and I/R + SLM50 (50 mg/kg). SLM was given orally for 7 days, followed by ischemia (2 h) and reperfusion (2 h) on day 8. Biochemical (MDA, GSH, SOD, CAT, GPx) and histological (H&E, Ki-67 IHC) analyses were performed. Also, molecular (qRT-PCR) analyses were performed to evaluate oxidative stress, inflammation, apoptosis, and Wnt signaling. I/R increased MDA and NO levels in ovarian tissue while decreasing SOD, CAT, GPx, and GSH. Antioxidant defense genes (Nrf-2, HO-1, NQO1) were suppressed, and inflammation markers (NF-ĸB, IL-1β, TNF-α) along with apoptotic markers (Bax, Caspase-3) were elevated, while Bcl-2 decreased. The Wnt signaling pathway was inhibited, particularly at Wnt-3A, LRP5, Dvl-2, and Cyclin-1, reducing Ki-67 protein levels and IHC positivity. Silymarin has shown a therapeutic effect on ovarian ischemia reperfusion injury with its antioxidant, antiapoptotic and anti-inflammatory effects and cell cycle regulatory activity.