Impact of losartan-supplemented extender on enhancing rooster sperm quality post-freezing and thawing

The cryopreservation of rooster sperm plays a pivotal role in artificial insemination programs. However, the process of sperm freezing and thawing often leads to damage, affecting the functional and biological properties of sperm cells. Losartan, a potent antioxidant and an angiotensin II type 1 receptor blocker, has been shown to modulate mitochondrial activity and exhibit antioxidant properties. This study was conducted using semen collected from 10 Cobb 500 roosters, and the pooled samples were allocated into five treatment groups corresponding to 0 (control), 15, 30, 45, and 60 µM Losartan. The control group consisted of semen extenders devoid of Losartan. Sperm samples were collected and diluted with the extender containing Losartan, followed by cryopreservation in liquid nitrogen. After thawing, sperm motility, plasma membrane integrity, mitochondrial activity, lipid peroxidation (LPO), and levels of antioxidant markers such as GPx, SOD, TAC, along with apoptosis-related changes, were assessed. Statistical analysis was performed using SAS software, with Tukey's test employed for multiple comparisons (P < 0.05 was considered significant). The results indicated that supplementation with 30 and 45 µM Losartan significantly improved total and progressive motility, mitochondrial activity, membrane integrity, and antioxidant levels, compared to other groups (P < 0.001). Furthermore, these concentrations of Losartan reduced LPO and apoptosis compared to control (P < 0.001). However, no significant effect was observed on sperm morphology (P > 0.05). This study suggests that Losartan has potential as a mitochondrial-targeted antioxidant in cryopreservation media, enhancing sperm quality and mitigating oxidative damage during freezing and thawing processes.