Prdx5 regulates macrophage polarization by modulating the TLR4/NF-κB pathway to promote apoptosis in chronic prostatitis

Objective and design：Prdx5 is a member of the thiol-dependent peroxidase superfamily with peroxidase activity. Previous studies have demonstrated that Prdx5 is involved in the development of inflammatory arthritis. However, the role of Prdx5 in apoptosis within chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) remains unclear. To elucidate the role of Prdx5 in chronic prostatitis and its underlying mechanisms. Material: Constructed experimental autoimmune prostatitis and conducted macrophage cell experiments. Treatment： Fifty microliters of rat male accessory gland extract mixed with complete Freund's adjuvant was injected into the shoulder, inguinal region, and tail of the mice, followed by a booster immunization two weeks later. Ten days prior to the initial immunization of EAP mice, 100 µL of AVV-shPrdx5 was administered via tail vein injection. The EAP mice from the initial immunization were treated with 150 mg/kg of N-acetylcysteine three times per week and EAP mice injected with AVV-shPrdx5 were injected with an NF-κB activator (5 mg/kg) for two weeks from the initial immunization. Methods: We assessed the severity of EAP through inflammation scoring, pain measurement, and hematoxylin and eosin (H&E) staining. The expression of macrophages and Prdx5 in the prostate was evaluated using immunofluorescence. The levels of macrophage inflammatory cytokines, polarization, reactive oxygen species (ROS), TLR4/NF-κB pathway proteins, and prostate epithelial cell apoptosis were measured using NO assay, RT-qPCR, flow cytometry, co-culture, TUNEL assay, and Western blotting. Results: Knocking out Prdx5 can inhibit macrophage M1 polarization through the Tlr4/NF-κB pathway in a ROS-dependent manner. Additionally, the knockdown of Prdx5 in macrophages has been shown to alleviate EAP-induced prostate epithelial cell apoptosis, thereby mitigating EAP. Conclusions: Our study demonstrates that Prdx5 regulates macrophage M1 polarization in EAP through the Tlr4/NF-κB pathway in a ROS-dependent manner, thereby alleviating prostatitis. This finding provides a new target for investigating the immunological mechanisms underlying CP/CPPS.