Developmental competence of mature yak vitrified–warmed oocytes is enhanced by IGF-I via modulation of CIRP during in vitro maturation
Authors: Kun Yang
Yangyang Pan
Gengquan Xu
Honghong He
Junfeng He
Abdul Rasheed Baloch
Sijiu Yu
Yan Cui
Jiangfeng Fan
Guyue Li
Journal: Cryobiology (2015)
Discipline: BIOLOGY & BIOCHEMISTRY
Keywords: CIRP; Developmental competence; IGF-1; Mature oocytes; Vitrification
Affiliations: Gansu Province Livestock Embryo Engineering Research Center, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China., University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Research Institute of Fish Culture and Hydrobiology, Zátiší 728/II, 389 25 Vodňany, Czech Republic., Gansu Province Livestock Embryo Engineering Research Center, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China. Electronic address: .

Abstract:  The objective of this study was to investigate whether developmental competence of mature vitrified-warmed yak (Bos grunniens) oocytes can be enhanced by supplemented insulin-like growth factor I (IGF-1) during in vitro maturation (IVM), and its relationship with the expression of cold-inducible RNA-binding protein (CIRP). In experiment 1, immature yak oocytes were divided into four groups, and IVM supplemented with 0, 50, 100 and 200 ng/mL IGF-1 was evaluated; the mRNA and protein expression levels of CIRP in mature oocytes in the four groups were evaluated using quantitative real-time PCR and western blotting analyses. In experiment 2, the mature yak oocytes in the four groups were cryopreserved using the Cryotop (CT) method, followed by chemical activation and in vitro culture for two days and eight days to determine cleavage, blastocyst rates, and total cell number in the blastocysts. Mature yak oocytes without vitrification served as a control group. The outcomes were as following: (1) the expression of CIRP in the matured oocytes was up-regulated in the IGF-1 groups and was highest expression was observed in the 100 ng/mL IGF-1 treatment group. (2) In the vitrified-warmed groups, the rates of cleavage and blastocyst were also highest in the 100 ng/mL IGF-1 treatment group (81.04 ± 1.06%% and 32.16 ± 1.01%), which were close to the rates observed in groups without vitrification (83.25 ± 0.85% and 32.54 ± 0.34%). The rates of cleavage and blastocyst in the other vitrified-warmed groups were 70.92 ± 1.32% and 27.33 ± 1.31% (0 ng/mL); 72.73 ± 0.74% and 29.41 ± 0.84% (50 ng/mL); 72.43 ± 0.61% and 27.61 ± 0.59% (200 ng/mL), respectively. There was no significant difference in the total cell number per blastocysts between the vitrified-warmed groups and group without vitrification. Thus, we conclude that the enhancement in developmental competence of mature yak vitrified-warmed oocytes after the addition of IGF-1 during IVM might result from the regulation of CIRP expression in mature yak oocytes prior to vitrification. 

Retracted: No

PubPeer comments:
 Figure 1. * Red boxes: panels B (vitrified-warmed oocytes treated with 100 ng mL IGF-1) and C (mature oocytes without vitrification) appear to show an area of overlap. ![file] , 
 Dear Elisabeth M Bik, Thank you very much for pointing out the error of Fig 1 in our published work. We have checked our original data and found we used wrong figure by mistake. In this paper, fig.1 is only used to show the morphology of the mature oocytes in different groups. Although this mistake has no influence to our results and conclusion, a revised Fig.1 and the original Fig.1c are provided here, which reflects our rigorous attitude to the article. This modification does not affect the interpretation or conclusions of this work. We regret this error. We apologize to our readers for any confusion this unintentional error might have caused. We have contacted the editorial department of the journal and submitted the right picture and ask for a corrigendum. We will more carefully process our data in our future work. Thank you again for helping us find and correct the mistake. Sincerely yours, Yangyang Pan ![file] ![file] , 
 February 2020 Corrigendum: https: www.sciencedirect.com science article pii S001122402030016X  We made a mistake in Fig 1. Specifically, panels B (vitrified-warmed oocytes treated with 100 ng mL IGF-1) and C (mature oocytes without vitrification) appear to show an area of overlap, owning to supplying the wrong panel C by mistake. In this paper, Fig. 1 was listed as the reference method, and only used to show the morphology that we referenced to select mature oocytes in different groups. Although this mistake has no influence to our results and conclusion, we added a new Fig. 1 to the attachment to replace the previous version for reflects our rigorous attitude to the article, and we would like to apologies for any inconvenience caused. I thank the authors and journal staff for correcting this error. ,