Effects of green tea polyphenols, insulin-like growth factor I and glucose on developmental competence of bovine oocytes

Abstract

-The present study examined the effects of green tea polyphenols (GTP), insulin-like growth factor-I (IGF-I) and glucose on oocyte in vitro maturation, subsequent embryo development and blastocyst quality in bovine. Cumulus-oocyte complexes (COC) were aspirated from the ovaries and cultured in synthetic oviduct fluid supplemented with MEM amino acids (SOFaa) media supplemented with one of the following supplements: GTP (0, 10, 15 and 20 μM), IGF-I (0, 50, 100 and 150 ng/mL) or glucose (0, 1.5, 5.6 and 20 mM) for 24 h. The results showed that oocytes cultured in media supplemented with 15 μM GTP, 100 ng/mL IGF-I and 5.6 mM glucose, in separate experiments, have higher cleavage and blastocyst rates compared with oocytes cultured in media without or with other concentration of GTP, IGF-I and glucose. Then these three substances with the concentration above were added together into SOFaa media and constituted a modified medium (Modified SOFaa). The COC were cultured in control SOFaa media and modified SOFaa media, respectively. The results showed that modified SOFaa media increased the intracellular glutathione concentration of matured oocytes, blastocyst rates and total cell numbers and cell numbers of inner cell mass per blastocyst compared with the control. Supplementing of GTP, IGF-I and glucose synchronously to maturation media can increase the intracellular GSH concentration of oocytes after in vitro maturation, and improve the embryo development and blastocyst quality in bovine.

Polyphenols in Farm Animals: Source of Reproductive Gain or Waste?

“…Substantial improvements in preserved (liquid or freezing storage) semen quality traits and sperm fertilization [ 130 , 131 , 133 , 134 ], oocyte development and competence, and embryo development [ 15 , 16 , 139 , 140 ] have been reported. The other evidence that could be observed from in vitro studies is that supplementation of polyphenolic compounds during gametes or embryo in vitro manipulation might continue to in vivo animals.…”

“…These facts explain the negative effects observed in some studies due to addition of high levels of polyphenols. For instance, bovine oocytes cultured in maturation medium supplemented with 15 μM/mL green tea polyphenols (99% catechin) derivatives, mainly EGCG, have higher intracellular glutathione (GSH) concentrations, maturation and cleavage rates, and blastocyst rates than those supplemented with 20 μM/mL [ 15 ]. In agreement with these observations, it has been stated that supplementation of a lower EGCG concentration (10 μg/mL) during in vitro fertilization significantly increased fertilization rate, while higher EGCG concentration (25 μg/mL) decreased fertilization rate [ 64 ].…”

“…However, the benefits may be more questionable in breeding animals; mainly because improper polyphenols intake may not only affect the reproductive performance of the parents but may also induce effects on the progeny, due to epigenetic changes affecting gene expression/programming and thus the future performance and health/disease status of the offspring [ 14 ]. These epigenetic effects may occur not only by parenteral exposure, but also through application of assisted reproductive techniques (ARTs) in which polyphenols, aiming its antioxidant or antibacterial effects, are included in the media of cryopreserved or cultured gametes/embryos [ 3 , 15 , 16 ].…”

Scoping review of primary studies evaluating Bovine in vitro oocyte maturation and embryo development

“…(97) IGF-1. Wang et al (98) reported that supplementation with polyphenols at 15 μM, 100 ng/mL IGF-1, and 5.6 mM glucose produced higher cleavage and blastocyst rates than did polyphenols at other concentrations. The authors concluded that these compounds could improve oocyte maturation, embryo development, and blastocyst quality in cattle.…”