Curcumin offers antioxidant protection to cryopreserved bovine semen

Abstract

Evidence shows that oxidative stress associated with sperm cryopreservation may lead to a significant decrease of the structural integrity and functional activity of male gametes. Curcumin (CUR) has become a substance of scientific interest for its free radical-quenching abilities, which could enhance the post-thaw quality of male gametes. This study assessed the effects of CUR on the post-thaw vitality and selected oxidative stress markers of bovine spermatozoa. Thirty ejaculates collected from 10 breeding bulls were divided into two aliquots and cryopreserved in the absence (control) or presence of CUR (50 μmol/l). Immediately before use, the control or experimental straws were thawed at 37°C for 20 s. CUR administration led to a significantly higher preservation of spermatozoa motion (P < 0.001) as well as membrane (P < 0.05) and acrosomal (P < 0.01) integrity in comparison with the control. Moreover, spermatozoa exposed to CUR exhibited a significantly higher mitochondrial activity (P < 0.001). Significantly decreased amounts of reactive oxygen species (P < 0.01) and superoxide (P < 0.001) were detected following CUR supplementation. Finally, a significant decrease of oxidative damage to proteins (P < 0.01), lipids (P < 0.001), and DNA (P < 0.05) was recorded in samples to which CUR was administered in comparison to the control. In this study, CUR proved to act as an efficient antioxidant molecule offering protection to male gametes against oxidative damage during cryopreservation.