Effects of 6-Gingerol Supplementation in Cryopreservation on Human Sperm Parameters, DNA Fragmentation, and Apoptosis Incidence.

Sperm cryopreservation is a valuable method for fertility preservation in men who suffer from oligozoospermia and cancer. The increase of oxidative stress during this process negatively affects the sperm viability, membrane fluidity, and function. Supplementation of antioxidants to the cryopreservation medium can reduce these negative effects. This study investigated the effects of 6-Gingerol as a natural antioxidant during human sperm cryopreservation on different sperm parameters, DNA fragmentation, and apoptosis. In this experimental study, semen samples were obtained from 42 normozoospermic men referred to the Royan Institute. The samples were randomly divided into Fresh, Control (cryopreservation), and Gingerol (cryopreservation with 6-Gingerol) groups. Sperm evaluations were conducted before and after cryopreservation. Sperm parameters, DNA fragmentation index (DFI), caspase-3 activity, reactive oxygen species (ROS) levels, malondialdehyde (MDA) concentration, and total antioxidant capacity (TAC) levels were assessed. Use of 6-gingerol in the cryopreservation medium resulted in the recovery of a significantly higher viable sperm post-cryopreservation compared to the control group (64.1 ± 1.3 % vs 56.4 ± 1.3 %; P = 0.000). The ROS levels were significantly lower (P = 0.000), and percent sperm with intact membrane potential was significantly higher (P = 0.000) in the gingerol group (26.1 ± 0.1 RLU/s, 63.5 ± 1.4 %) compared to the control group (32.1 ± 0.7 RLU/s, 53.3 ± 1.5 %). Active caspase-3 (P = 0.007) and DFI (P = 0.008) were non-significantly lower in the gingerol group (47.3 ± 3.6 %, 37.9 ± 1.3 %, respectively) compared to the control group (60.5 ± 3.6 %, 42.1 ± 0.1 %, respectively). Supplementing sperm cryopreservation medium with 6-Gingerol could improve sperm quality and function, and positively affect the degree of apoptosis incidence during sperm freezing.