PTK2B inhibitor PF-431396 inhibits inflammatory response and apoptosis of ovarian granulosa cells by targeting AKT1 phosphorylation in premature ovarian insufficiency.

Premature ovarian insufficiency (POI) is a female reproductive disorder characterized by impaired ovarian function. Protein tyrosine kinase 2 beta (PTK2B), a non-receptor tyrosine kinase, has been implicated in folliculogenesis, but its role in POI remains unknown. In this study, a rat POI model was established by intraperitoneal injection of cyclophosphamide (Cy) for 14 days. Electroacupuncture (EA) has been elicited to effectively improve ovarian function in POI. Here, mRNA sequencing (mRNA-seq) analysis found that PTK2B expression in ovarian tissues was upregulated by Cy treatment but downregulated by EA. To investigate PTK2B's role, primary rat ovarian granulosa cells (GCs) were co-treated with Cy (250 μM) and a PTK2B inhibitor PF-431396 (10 μM) for 48 h. PF-431396 inhibited Cy-induced inflammatory response and apoptosis in GCs. Further, PTK2B binds to AKT1 in GCs. PF-431396 facilitated AKT1 phosphorylation, and the inhibitory effects of PF-431396 on GC inflammatory response and apoptosis were reversed by an AKT1 inhibitor LY294002. In vivo, rats were given PF-431396 (10 mg/kg/d) by gavage for 7 days following Cy induction for 14 days. Treatment with PF-431396 increased ovarian weight, serum E2, and AMH levels, while decreased FSH and LH levels. Additionally, it could improve Cy-induced ovarian tissue injury, inhibit inflammation and apoptosis, and elevate p-AKT1 level in ovarian tissues. Together, our results unveil that PF-431396, a PTK2B inhibitor, ameliorates ovarian dysfunction in POI through promoting AKT1 phosphorylation, suggesting that PTK2B may be a therapeutic target for POI.