Molecular and physiochemical evaluation of buck semen cryopreserved with antioxidants

Abstract

The current study evaluated the physiochemical quality and gene expression profile of post‐thawed buck semen after supplementation with antioxidants [melatonin (M), L‐carnitine (LC), cysteine (Cys), LC + M, M + Cys, LC + Cys, LC + Cys + M] in comparison with the non‐treated control group. Physical and biochemical characteristics of semen were evaluated following freezing and thawing. Transcript abundance of six selected candidate genes was profile using quantitative real‐time PCR. The data demonstrated significant enhancement of post‐freezing total motility, progressive motility, percentage of live sperm, CASA parameters, plasma membrane and acrosome integrity in all groups supplemented with Cys, LC, M + Cys and LC + Cys compared with the control group. The biochemical analysis of semen indicated that semen groups supplemented with LC and LC + Cys recorded increased levels of GPX and SOD that were coupled with up‐regulation of antioxidant genes (SOD1, GPX1 and NRF2) and mitochondrial transcripts (CPT2 and ATP5F1A). Moreover, H2O2 level and DNA fragmentation percentage were reduced compared with other groups. In conclusion, supplementation of Cys alone or in combination with LC positively improved the post‐thaw physiochemical properties of rabbit semen through activation of bioenergetics‐related mitochondrial genes and cellular antioxidant defence mechanism.

Redox Homeostasis and Nrf2-Regulated Mechanisms Are Relevant to Male Infertility

“…By considering the supporting role of Nrf2 to spermatogenesis and sperm quality, Sadeghiani et al [99] reported that pentoxifylline supplementation during freezing protocol and long-term storage protected mouse spermatogonial stem cell activating the antioxidant defense through the Nrf2/ARE signaling pathway. In addition, the transcription of NRF2, together with that referred to SOD1 and GPx1, was up-regulated in post-thawed buck semen after supplementation with antioxidants [100].…”