Peer Review #2 of "The antioxidative properties of S-allyl cysteine not only influence somatic cells but also improve early embryo cleavage in pigs (v0.1)" [peer_review]

L You
2016 unpublished
In vitro cultivation systems for oocytes and embryos are characterised by increased levels of reactive oxygen species (ROS), which can be balanced by the addition of suitable antioxidants. S-allyl cysteine (SAC) is a sulfur compound naturally occurring in garlic (Allium sativum), which is responsible for its high antioxidant properties. In this study we demonstrated the capacity of SAC (0.1, 0.5 and 1.0 mM) to reduce levels of ROS in maturing oocytes significantly after 24 (reduced by 90.33%,
more » ... educed by 90.33%, 82.87% and 91.62% respectively) and 48 hour (reduced by 86.35%, 94.42% and 99.05% respectively) cultivation, without leading to a disturbance of the standard course of meiotic maturation. Oocytes matured in the presence of SAC furthermore maintained reduced levels of ROS even 22 hours after parthenogenic activation (reduced by 66.33%, 61.64% and 57.80% respectively). In these oocytes we also demonstrated a growth of early embryo cleavage rate (increased by 33.34%, 35.00% and 35.00% respectively). SAC may be a valuable supplement to cultivation media. PeerJ reviewing PDF | Abstract 27 In vitro cultivation systems for oocytes and embryos are characterised by increased levels of 28 reactive oxygen species (ROS), which can be balanced by the addition of suitable antioxidants. 29 S-allyl cysteine (SAC) is a sulfur compound naturally occurring in garlic (Allium sativum), 30 which is responsible for its high antioxidant properties. In this study we demonstrated the 31 capacity of SAC (0.1, 0.5 and 1.0 mM) to reduce levels of ROS in maturing oocytes significantly 32 after 24 (reduced by 90.33%, 82.87% and 91.62% respectively) and 48 hour (reduced by 86.35%, 33 94.42% and 99.05% respectively) cultivation, without leading to a disturbance of the standard 34 course of meiotic maturation. Oocytes matured in the presence of SAC furthermore maintained 35 reduced levels of ROS even 22 hours after parthenogenic activation (reduced by 66.33%, 61.64% 36 and 57.80% respectively). In these oocytes we also demonstrated a growth of early embryo 37 cleavage rate (increased by 33.34%, 35.00% and 35.00% respectively). SAC may be a valuable 38 supplement to cultivation media. 39 40 Introduction 41 During meiotic maturation in in vitro conditions, oocytes acquire developmental competence, 42 which is decisive with regard to the capacity of the fertilised oocyte to develop into a viable 43 embryo (Wassarman, 1988). Oxidative stress negatively influences meiotic maturation by 44 influencing the properties of its cytoskeleton. It damages the microfilaments of the maturing 45 oocyte (Jiao et al., 2013), disturbs the dynamics of the microtubular network and the attachment 46 of chromosomes to microtubules (Choi et al., 2007). Oxidative stress negatively influences PeerJ reviewing PDF |
doi:10.7287/peerj.2280v0.1/reviews/2 fatcat:qh4ug7jo5bcmrlyauxdtgupdci