The roles of reactive oxygen species and antioxidants in cryopreservation

Abstract

Cryopreservation has facilitated advancement of biological research by allowing the storage of cells over prolonged periods of time. While cryopreservation at extremely low temperatures would render cells metabolically inactive, cells suffer insults during the freezing and thawing process. Among such insults, the generation of supra-physiological levels of reactive oxygen species (ROS) could impair cellular functions and survival. Antioxidants are potential additives that were reported to partially or completely reverse freeze-thaw stress-associated impairments. This review aims to discuss the potential sources of cryopreservation-induced ROS and the effectiveness of antioxidant administration when used individually or in combination.

The Importance of Oxidative Stress in Determining the Functionality of Mammalian Spermatozoa: A Two-Edged Sword

“…In addition to the use of antioxidant enzymes to curtail oxidative stress during cryopreservation a large number of small molecular mass free radical scavengers have also been deployed for this purpose; entry of the terms "cryopreservation" and "antioxidants" into PubMed yields over 3000 references and the area has recently been thoroughly reviewed [84]. The antioxidants assessed included ascorbic acid, α-tocopherol, reduced glutathione, zinc oxide nanoparticles, zinc sulphate, resveratrol, quercetin, melatonin, L-carnitine, coenzyme Q, hypotaurine/taurine and butylated hydroxytoluene.…”

Antioxidants in Fish Sperm and the Potential Role of Melatonin

“…Moreover, in artificial reproductive techniques, like cryopreservation, oxidative stress has been considered the main reason for spermatozoa malfunctions [ 14 ]. Although ROS production is not a specific threat of the reproductive cells [ 15 ], according to Cabrita, et al [ 1 ], fish spermatozoa membrane is a perfect target for ROS, which may also cause lipid and protein peroxidation, damage on midpiece and axoneme, DNA fragmentation and mitochondrial impairment ( Figure 1 ) [ 16 , 17 ]. All this damage can consequently lead to a decrease in sperm motility and fertilization capacity [ 5 , 14 ].…”

“…It is considered a potent antioxidant because it acts on both aliphatic and aqueous cell environments with the capacity to detoxify ROS and RNS and regulates other antioxidant enzymes [ 13 ]. Moreover, MEL can up-regulate anti-apoptotic genes ( bcl2l1 ( bcl-xL family) and bcl-2 ) and down-regulate pro-apoptotic genes ( bax ) ( Figure 1 ) [ 15 ], which is crucial to prevent cellular apoptosis. This indolamine was first thought to be produced only by the pineal organ, but nowadays, it is known that MEL is also produced by many organs and tissues, being mitochondria one of the main producing organelles, reaching concentrations even higher than in bloodstream [ 173 , 174 ].…”

Recent progress in bovine in vitro‐derived embryo cryotolerance: Impact of in vitro culture systems, advances in cryopreservation and future considerations

“…The success of an OPU‐IVP program depends greatly on the quantity and quality of retrieved cumulus oocyte complexes (COCs) (Merton et al, 2003), as well as donor age, breed, physiological status (open, pregnant, days post‐partum), nutrition, body condition score, expertise of OPU personnel, ultrasound screen definition, aspiration pump regulation/stability, OPU session interval and hormonal (pre)‐treatment, among many others (Merton et al, 2003). Oocyte origin, follicle microenvironment (status and size) along with many other factors such as donor nutrition, calf raising history, environment, stress level and health, among many other factors, could have a great impact on the oocyte and embryo competence (Borges & Vireque, 2019; Len, Koh, & Tan, 2019; Lonergan, Monaghan, Rizos, Boland, & Gordon, 1994). These factors can alter oocyte morphology, lipid composition and transcriptome and, therefore, affect blastocyst yield.…”

“…Many factors can affect embryo competence and cryosurvival (donor status, follicular microenvironment, oocyte quality, IVP media and production conditions, among others), and attention to details is required in order to increase productivity and consistent embryo yields. High lipid content and accumulation of lipid droplets and the high levels of reactive oxygen species (ROS) produced during the culture period are the most damaging factors that undermine IVP efficiency in terms of embryo development yield and cryotolerance (Abe et al, 2002; Bradley & Swann, 2019; Len et al, 2019). Therefore, managing the proper lipid content represents a major challenge since metabolic function needs and cell energy source demands must be balanced with embryo cryotolerance integrity (Dunning, Russell, & Robker, 2014).…”