Usage of Some Natural or Synthetic Compounds as Antioxidant and their Effects on Cryopreservation and Penetration of Ram Spermatozoa

Abstract

T he chilling of semen has some adverse effects on sperm properties. Modifying dilators with traditional and untraditional refrigerants can influence sperm properties (Mohamed et al., 2020). Preservation of semen alters sperm structure and biochemical properties and impedes fertilization (Mohamed et al., 2019).The addition of antioxidants to semen diluents could be extended storage time, improve motility, decrease cellu-lar damage, protected acrosomal membrane and raise the viability and fertilization ability of spermatozoa. Among substances with recognized antioxidants effectiveness were natural or synthetic to be added to extenders. In this context, vitamin E (synthetic non-enzymatic antioxidant) is one of the most principal lipid-soluble defensive antioxidants and has a major role as an antioxidant. Hence, Ahmadi Hamedani et al. (2016) indicated that supplementation 2mM of vitamin E as an antioxidant is suggested to improve cryopreservation techniques in ram sperm. Moreover, Motemani et al. (2017) demonstrated that concentrations research Article Abstract | The current investigation was performed for determining the impact of natural (rosemary and ginseng aqueous extracts) and synthetic (L-carnitine and vitamin E) antioxidants on ram sperm characteristics during three sessions (preservation, equilibration, and frozen-thawing) using six mature Ossimi rams. Semen collection was performed twice a week for three weeks by an artificial vagina. In different sessions, ejaculates were pooled split into five aliquots. The natural (rosemary and ginseng aqueous extracts) and synthetic (L-carnitine and vitamin E) antioxidants were supplemented 20 mg/ml of each to the first four portions G1, G2, G3, and G4, respectively. However, the fifth part (G5) served as control without any antioxidant type. The results showed that sperm characteristics, sperm recovery rate and reduced glutathione (GSH) were higher (P < 0.05), but the concentration of lipid peroxidation (LPX) and enzymatic activities (ALT, AST, ALP, and LDH) were lower (P < 0.05) in G1, G2, G3 and G4 than G5 extenders post-equilibration and thawing conditions. Furthermore, the penetration ability into ewe cervical mucus was significantly (P < 0.05) better in the extended ram semen with natural antioxidant (G1 & G2) than with synthetic antioxidant (G3 & G4). The findings of this study indicated that extenders supplemented with rosemary or ginseng extract (as a natural antioxidant) could be alleviated sperm characteristics, penetration value and reduced oxidative stress marker corresponding to L-carnitine and vitamin E (as a synthetic antioxidant) during after the cooling and freezethawing processes of ram spermatozoa.

Recent approaches in the use of antioxidants and proteomic modifications in ram semen preservation

“…Bezerra et al (2022) discovered that a 12.5 μg/mL concentration of rosemary extract increased sperm motility, improved membrane integrity at 25 μg/mL, and enhanced acrosome integrity at 6.25 μg/mL after thawing. Moreover, Diab et al (2021) demonstrated that the use of 20 mg of rosemary extract in the ram semen extender at 37 and 5°C improved motility, live sperm count, and reduced abnormality rates. This improvement in semen quality might be associated with the ability of herbs to enhance the antioxidant defence system and reduce the synthesis of OS in sperm.…”