Effect of thymoquinone on Prdx6 expression in testicular torsion

Testicular torsion is an emergency condition resulting from the twisting of the spermatic cord around itself, which leads to impaired blood flow and subsequent ischemia of the testis. It is most commonly seen during childhood and adolescence. Testicular torsion affects approximately 4.5 out of every 100,000 males under the age of 25 annually. Ischemia and reperfusion (I/R) resulting from testicular torsion-detorsion (T/D) can lead to testicular damage, infertility, and organ dysfunction. It typically presents with scrotal pain radiating to the lower abdomen, and may be accompanied by symptoms such as nausea and vomiting. Although the exact cause of testicular torsion is often unknown, trauma accounts for approximately 20% of cases. Ischemia resulting from testicular torsion increases the levels of reactive oxygen species (ROS). Elevated ROS production can lead to DNA damage, endothelial destruction, and apoptosis of testicular germ cells. To prevent testicular dysfunction, various antioxidants are being investigated. Peroxiredoxins (PRDXs) are antioxidant enzymes that prevent ROS-induced cellular damage. One of the bioactive components of black seed (Nigella sativa), thymoquinone (TQ), possesses significant anti-inflammatory and antioxidant activities. Studies have shown that thymoquinone can suppress oxidative stress. The aim of our study is to investigate whether thymoquinone, which has antioxidant properties, provides a protective effect against testicular ischemia-reperfusion injury through the regulation of Prdx6 expression. For this purpose, 30 male rats were divided into the following groups: control (DMSO), sham (operation only), torsion/detorsion, thymoquinone, and thymoquinone + torsion/detorsion. Thymoquinone was administered intraperitoneally at a dose of 10 mg/kg daily for 7 days in the thymoquinone and thymoquinone + torsion/detorsion groups, followed by the creation of a torsion/detorsion model. After the model was established, Gomori trichrome staining and immunohistochemical techniques were applied to the testicular tissue. In the Torsion/Detorsion group, significant histopathological damage was observed in the testicular tissue, whereas thymoquinone treatment reduced this damage and preserved tubular integrity. Prdx6 and GLP-1 expression increased in the Torsion/Detorsion group, while it decreased in the thymoquinone-treated group. These findings indicate that thymoquinone provides antioxidant protection in testicular tissue by regulating the expression of Prdx6 and GLP1. Keywords: Testis, Torsion, Thymoquinone, Prdx6, Ischemia/Reperfusion