Coenzyme Q₁₀ supplementation during in vitro maturation of bovine oocytes (Bos taurus) helps to preserve oocyte integrity after vitrification

Abstract

Contents Oocyte vitrification causes less cell stress than slow cooling, but cytoskeletal and spindle alterations may occur affecting the oocyte competence. In vitro maturation (IVM) supplementation with different antioxidant molecules has been performed to attenuate this harmful stress. Coenzyme Q10 (CoQ10) supplementation has previously shown to have positive effects in bovine and mouse in vitro embryo development. The aim of this study was to evaluate the effects of CoQ10 during bovine oocyte IVM and vitrification. Cumulus–oocyte complexes (COCs) (n = 311) were cultured under standard maturation conditions with 0 μM (control), 25 μM and 50 μM CoQ10 supplementation. After 22 hr, a cohort of 170 oocytes both from the control and from CoQ10‐supplemented groups were vitrified, warmed and returned to incubation until 24 hr of maturation, while the rest of the oocytes (n = 141) remained fresh. Then, oocyte survival was assessed morphologically by stereomicroscopy. Oocytes from all groups were then fixed and stained for assessing cortical granules (CG) migration and nuclear stage. High rates of oocyte MII progression and appropriate CG migration as a continuous layer beneath the plasma membrane were obtained both in control and in CoQ10 groups. Results showed that although vitrification has great impact in survival of IVM bovine oocytes, 50 μM CoQ10 supplementation significantly improved oocyte survival (p = .045) and reduced the premature CG exocytosis, helping to preserve the CG migration pattern (31.3% control vs. 54.5% in 50 μM CoQ10; p = .039), attenuating the negative effects of vitrification.

Supplementation with exogenous coenzyme Q10 to media for in vitro maturation and embryo culture fails to promote the developmental competence of porcine embryos

“…Such data suggest that CoQ10 positively supports oocyte developmental competence only under moderate damage (fall) but has no effect when the damage before culture is insignificant (winter) or extreme (summer). Lastly, some studies reported positive effects of CoQ10 during IVM on survival post‐warming following vitrification (Ruiz‐Conca et al., ). In addition, supplementation of CoQ10 during the recovery culture (post‐warming medium) has led to higher blastocyst yields among vitrified‐warmed pig oocytes, obeying to increased survival rates and the presence of regulating mRNA expression (Hwang et al., ).…”

“…The effects of exogenous CoQ10 under moderate‐heat stress not only improved mitochondrial distribution, membrane polarization and differential expression of genes involved in the mitochondrial electron transport chain, but also improved oocyte developmental competence (Gendelman & Roth, ). Exogenous CoQ10 in the maturation medium also improved oocyte survival and reduced the premature exocytosis of the cortical granules following vitrification and warming of immature oocytes (Ruiz‐Conca, Vendrell, Sabés‐Alsina, Mogas, & Lopez‐Bejar, ). Unfortunately, corresponding data on the effects of exogenous CoQ10 in pigs are more limited.…”

Resveratrol enhanced mitochondrial recovery from cryopreservation‐induced damages in oocytes and embryos

“… 27 , 28 Therefore, the effect of antioxidants on oocytes and embryo following vitrification has been extensively studied; supplementation of culture medium of vitrified‐warmed oocytes or embryos with melatonin, glutathione ethyl‐ester, N‐acetyl cysteine, α‐tocopherol, or coenzyme Q reduced ROS levels and improved oocyte viability as well as embryo development in equine, cows, and mice. 6 , 29 , 30 , 31 , 32 In addition, supplementation of vitrified‐warming solution with acetyl‐L‐carnitine, N‐acetyl‐cysteine, and lipoic acid improved the cell number of the blastocysts and fetal development in mice. 33 Furthermore, addition of vitamin E to the culture medium of vitrified‐warming ovarian tissue improved oocyte and subsequent blastocyst stage development.…”

Cryopreservation of farm animal gametes and embryos: recent updates and progress

“…Other chemicals, such as conjugated linoleic acid [75] , L-carnitine [76] , glutathione [77] and a cAMP agonist [78] have also improved outcomes. Cholesterol, coenzyme Q10, BAPTA-AM (Ca 2+ chelator) and ruthenium red have also improved the freezability of in vitro matured bovine oocytes [79][80][81] . Liquid helium vitrification of immature bovine oocytes had better outcomes for reducing injury to the cytoskeleton structure and improving the viability compared with liquid nitrogen vitrification [82] .…”