Effects of insulin-like growth factor-1 on the <i>in vitro</i> maturation of canine oocytes

Abstract

The maturation rate of canine oocytes during in vitro maturation (IVM) needs to be improved. The present study was designed to evaluate the effects of insulin-like growth factor-1 (IGF-1) on the IVM of canine oocytes. Ovaries were obtained by ovariohysterectomy and were sliced to release cumulus-oocyte complexes (COCs). In Experiment 1, the effects of different concentrations of IGF-1 on the nuclear maturation of oocytes was investigated. The COCs were cultured in a modified medium (mTCM199) with IGF-1 (0, 0.5, 5, 10, and 50 µg/ml). At the end of the 48 h culture, oocytes were fixed and stained to evaluate their nuclear stage. Supplementation with 50 µg/ml IGF-1 induced a significantly higher metaphase II (MII) rate (P < 0.05) compared to the 0 and 0.5 μg/ml IGF-1 groups. In Experiment 2, the expression levels of insulin receptor (INSR), IGF-1 receptor (IGF-1R), and IGF-2 receptor (IGF-2R) genes, localized to canine oocytes and cumulus cells, were investigated before and after IVM. The expression level of IGF-1R in cumulus cells after IVM was higher than that before IVM (P < 0.05). In Experiment 3, it was investigated whether an inhibitor of PTEN (phosphatase and tensin homolog), bpV, affects the nuclear maturation of oocytes. Regardless of bpV supplementation at a concentration of 0.2 to 200 µmol/l, there was no significant difference in the proportion of oocytes that reached the MII stage. These results indicated that IGF-1 has a favorable effect on the IVM of canine oocytes, possibly through the stimulation of the Ras/MAPK pathway via IGF-1R expressed in cumulus cells.

Nuclear competence and genetic expression of growth differentiation factor‐9 (GDF‐9) of canine oocytes in 3D culture

“…Optimal conditions for in vitro maturation (IVM) of canine oocytes are not yet established (Luvoni, Chigioni, Allievi, & Macis, ), although a wide variety of supplemented culture medium with different compounds, steroids, gonadotropins, oviductal microvesicles or bi‐phasic systems were tested (Apparicio et al., , ; Lange‐Consiglio et al., ; Sato et al., ). The highly variable results could be due either to suboptimal culture conditions and/or to the low competence of female gametes to develop into a fertilizable oocyte and into an embryo.…”

Effect of cysteine, insulin-like growth factor-1 and epidermis growth factor during in vitro oocyte maturation and in vitro culture of yak-cattle crossbred embryos

“…In cattle, 100-200 ng/ml EGF and 50-100 ng/ml IGF-I were suggested by Sakagami et al (2012), but 50 ng/ml EGF and 100 ng/ml IGF-I were suggested by Arat et al (2016). It appears that the optimal concentrations of EGF and IGF-1 were some different among different animal species (Sirisathien et al 2003;Choe et al 2010;Shabankareh and Zandi 2010;Thongkittidilok et al 2015;Zhou et al 2016;Sato et al 2018).…”

“…EGF and IGF-1 are involved in regulating cell proliferation and apoptosis (Paria and Dey 1990;Wasielak and Bogacki 2007;Chen et al 2017). Positive effects on oocyte maturation and/or embryonic development have been observed if a single or different combination of Cys, EGF and IGF-1 concentrations in IVM, IVF and IVC media is optimal in cattle (Ali et al 2003;Sirisathien et al 2003;Neira et al 2010;Nabenishi et al 2012), pig (Choe et al 2010;Lott et al 2011), sheep (Shabankareh and Zandi 2010), buffalo (Pawshe et al 1998), human (Yu et al 2012), mouse (Toori et al 2014); cat (Thongkittidilok et al 2015), goat (Conceicao et al 2016;Zhou et al 2016), canine (Sato et al 2018) and yak (Pan et al 2015;Chen et al 2017).…”

“…The desirable IVP efficiency of crossbred embryos is prerequisite for F1 producing F1, but it is considerably low at present (Zi et al 2009). Cysteine (Cys), insulin-like growth factor-1 (IGF-1) and epidermis growth factor (EGF) have been shown to promote oocyte maturation and embryo development in many mammalian species (Pawshe et al 1998;Sirisathien et al 2003;Choe et al 2010;Neira et al 2010;Shabankareh and Zandi 2010;Nabenishi et al 2012;Yu et al 2012;Toori et al 2014;Thongkittidilok et al 2015;Zhou et al 2016;Sato et al 2018), but there is little information about the yak (Pan et al 2015;Chen et al 2017). Therefore, the objective of this study was to investigate the effects of Cys, IGF-1 and EGF on yak oocyte maturation and development of yak-cattle crossbred embryos in vitro.…”

microRNA expression profile in porcine oocytes with different developmental competence derived from large or small follicles

“…Target gene prediction identified insulin‐like growth factor 1 receptor ( IGF1R ) as one of the genes commonly targeted by all DE miRNAs. The expression of IGF1R promotes the meiotic progression of oocytes from the MI to MII stage in the canine oocytes (Sato et al, ). Insulin‐like growth factor 1 (IGF‐1) activates two main signaling pathways (PI3K/Akt and Ras/MAPK) via IGF1R (Murphy & Hu, ).…”