Sperm Cryopreservation: Principles and Biology

Abstract

Cryopreservation is a widely used method to preserve sperm prior to any cytotoxic therapy or testicular surgical intervention to be used later for assisted conception. Despite of multiple modifications in cryopreservation protocols, the yield of post-thaw good quality sperm has not been improved much. There is little data regarding factors affecting cryopreservation techniques and outcomes. Present review focuses on the basic biology of cryopreservation, its current protocols and effects on sperm proteomic and epigenomic modifications.

Effect of Carbohydrate Type and Phenotype on the Quality of Post-Thawing Frozen Semen of KUB Chicken

“…Freezing can cause changes in sperm morphology. These changes are caused by changes in the ultrastructural of sperm due to drastic temperature changes, osmotic pressure, and the formation of crystal ice in sperm (Sharma & Sharma 2020).…”

Effect of Genistein Supplementation in Tris-Aminomethane Base Extender on Characteristics of Pre-Freezing and Post-Thawed Sperm Ongole Grade Bull

“…The processing frozen semen is a series of processes that involve physical, physiological and biochemical activities of sperm (Sharma and Sharma, 2020). Physically, there is a change in the structure and volume of the spermatozoa cells when they enter the liquid phase into the frozen phase, resulting in shrinkage or swelling according to the diluent medium and the freezing process, the linear length curve decreased by 33% after dilution-cooling and 22% after cooling freezing (Agca et al, 2002;Hussain et al, 2011).…”

“…Physically, there is a change in the structure and volume of the spermatozoa cells when they enter the liquid phase into the frozen phase, resulting in shrinkage or swelling according to the diluent medium and the freezing process, the linear length curve decreased by 33% after dilution-cooling and 22% after cooling freezing (Agca et al, 2002;Hussain et al, 2011). During the freezing process, spermatozoa undergo tremendous biochemical changes where the metabolic system tries to be inhibited or stopped through a very low temperature drop, so that spermatozoa cells are no longer able to carry out biochemical reactions (Agca et al, 2002;(Sharma and Sharma, 2020). As a result of the freezing process, there were many changes in the quality of spermatozoa which were generally observed in decreased motility, viability, membrane integrity, acrosome capacitation and status, and fertility.…”

Strategies for Bacterial Eradication from Human and Animal Semen Samples: Current Options and Future Alternatives

“…Early attempts for sperm vitality conservation may be traced back to 1776, when Spallanzani froze spermatozoa using snow and subsequently demonstrated their motility after rewarming [ 1 ]. Since then, remarkable progress in the evolution of techniques and media for short- or long-term semen storage has allowed sperm preservation to overcome numerous space and time limitations, and thus to become an integral part of assisted reproduction technologies (ARTs) in animals and humans [ 1 , 2 ].…”

“…Sperm preservation, at low temperatures and when properly performed, enables the long-term storage of male gametes in a state of metabolic arrest that prevents cellular senescence while maintaining their viability and fertilizing potential, therefore this allows them to be used when and where they are needed [ 2 ]. While the role of sperm storage at low temperatures as a critical pillar of reproductive technologies is undoubtable, the rationale behind its use for the management of male fertility may differ between animal and human ARTs [ 3 , 4 , 5 , 6 , 7 ].…”