Abstract
Background:
Cyclophosphamide (CTX) is a widely used chemotherapeutic agent; however, its clinical application is often limited by significant reproductive toxicity, particularly testicular damage. Baicalin has demonstrated broad pharmacological activities, including anti-inflammatory, antioxidant, and anti-apoptotic effects.

Aim:
To investigate the protective effect of baicalin on testicular damage induced by cyclophosphamide in rats.

Methods:
Network pharmacology was used to identify the core targets of baicalin-testis damage. Animal experiments were conducted using 30 SPF-grade 7-week-old SD rats divided into a control group (Control), a cyclophosphamide group (CTX), a low-dose baicalin group (BAI-L), a medium-dose baicalin group (BAI-M), and a high-dose baicalin group (BAI-H), with six rats in each group. Molecular docking , quantitative polymerase chain reaction (qPCR), and Western blot were used to validate the core targets of network pharmacology. H&E staining was performed to observe testicular tissue damage. The levels of IL-1β, IL-10, ROS, and MDA in the testes and the levels of FSH, LH, and T in the serum were measured. Immunofluorescence was used to detect germ, supporting, and interstitial cells in the testes.

Results:
Network pharmacology identified 127 common targets between baicalin and testicular damage. Baicalin acts on Ptgs2, Gsk3b, and Pparg targets. Molecular docking and animal experiments indicated that baicalin exhibits strong binding affinity with Ptgs2, Gsk3b, and Pparg. Animal experiments showed that baicalin can improve CTX-induced pathological tissue damage, reduce inflammatory responses, and alleviate oxidative stress in rat testes. Baicalin can repair CTX-induced damage to germ cells, supporting cells, interstitial cells, and repaired reproductive hormones, with the extent of repair showing a dose-dependent relationship.

Conclusion:
This study demonstrates the beneficial effects of baicalin in alleviating CTX-induced reproductive toxicity, and baicalin can be used to reduce the side effects of CTX.

Key words: Baicalin; Cyclophosphamide; Network pharmacology; Reproductive hormones; Testicular injury.