Nanoliposome‐Mediated Delivery of Lipophilic Antioxidants as a Strategy to Improve the Preservation Capacity of Pig Semen at 17°C

ABSTRACT

While lipophilic antioxidants such as flavonols may improve the preservation capacity of sperm at 17°C, their low stability and bioavailability can reduce their biological effectiveness. Encapsulation strategies have been proposed to improve the delivery and cellular availability of hydrophobic antioxidants. Herein, we investigated whether delivering one of these flavonols (kaempferol) in nanoliposomes can improve the preservation capacity of pig semen at 17°C. Twelve semen samples were supplemented with kaempferol‐loaded nanoliposomes (KNL) or free kaempferol (5 μM), and stored at 17°C for 48 h. Sperm motility was assessed using a computer‐assisted sperm analysis system, and functional parameters were evaluated by flow cytometry. After 48 h, sperm stored with KNL showed lower intracellular reactive oxygen species and superoxide levels than those stored with free kaempferol. In addition, the integrity of the plasma membrane and acrosome was better maintained in samples containing KNL. Conversely, mitochondrial membrane potential and most kinematic parameters in sperm stored with KNL did not differ from those supplemented with free kaempferol, yet curvilinear velocity was higher in the former than in the latter. These findings indicate that nanoliposomal delivery enhances the biological effectiveness of 5 μM kaempferol, improving its antioxidant and protective effects on pig sperm. Further research is warranted to improve sperm preservation capacity by delivering lipophilic antioxidants via nanoliposomes.