C-kit signaling promotes human pre-implantation 3PN embryonic development and blastocyst formation

• Published in: Reproductive biology and endocrinology 2019-09, Vol.17 (1), p.75-75, Article 75
• Main Authors: Tan, Jun, Zou, Yang, Huang, Zhi-Hui, Zhang, Zhi-Qin, Wu, Li-Ping, Wu, Xing-Wu, Wan, Xiao-Ju, Xin, Cai-Lin, Wu, Qiong-Fang
• Format: Article
• Language: English
• Subjects: Adult; Animals; Blastocyst - metabolism; Blastocysts; C-kit; c-Kit protein; Care and treatment; Cell receptors; Cellular signal transduction; DNA-Binding Proteins; Embryo Culture Techniques - methods; Embryo Implantation - genetics; Embryo Transfer - methods; Embryogenesis; Embryonic development; Embryonic Development - genetics; Embryos; ETV5; Female; Female infertility; Gene Expression Regulation, Developmental; Health aspects; Human fertilization in vitro; Humans; Immunofluorescence; In vitro culture; IVF; Membrane proteins; Metabolic pathways; Methods; Mice, Inbred ICR; Oocytes; Phosphorylation; Polymerase chain reaction; Pregnancy; Pronucleus; Proto-Oncogene Proteins c-kit - genetics; Proto-Oncogene Proteins c-kit - metabolism; Quality; Signal Transduction - genetics; Transcription Factors
• ISSN: 1477-7827; 1477-7827
• DOI: 10.1186/s12958-019-0521-8

Although in vitro culture system has been optimized in the past few decades, the problem of few or no high quality embryos has been still not completely solved. Accordingly, fully understanding the regulatory mechanism of pre-implantation embryonic development would be beneficial to further optimize the in vitro embryo culture system. Recent studies have found the expression of c-kit in mouse embryo and its promotion effects on mouse embryonic development. However, it is unclear the expression, the role and the related molecular regulatory mechanism of c-kit in human pre-implantation embryo development. Therefore, the present study is to determine whether c-kit is expressed in human pre-implantation embryos, and to investigate the possible regulatory mechanism of c-kit signaling in the process of embryonic development. The present study includes human immature oocytes and three pronucleus (3PN) embryos collected from 768 women (28-32 ages) undergoing IVF, and normal 2PN embryos collected from ICR mice. Samples were distributed randomly into three different experimental groups: SCF group: G-1™ (medium for culture of embryos from the pro-nucleate stage to day 3) or G-2™ (medium for culture of embryos from day3 to blastocyst stage) + HSA (Human serum album) solution + rhSCF; SCF + imanitib (c-kit inhibitor) group: G-1™ or G-2™ + HSA solution + rhSCF + imanitib; SCF + U0126 (MEK/ERK inhibitor) group: G-1™ or G-2™ + HSA solution + rhSCF + U0126; Control group: G-1™ or G-2™ + HSA solution + PBS; The rate of good quality embryos at day 3, blastulation at day 6 and good quality blastulation at day 6 were analysis. RT-PCR, western blot and immunofluorescence staining were applied to detect the target genes and proteins in samples collected from human or mice, respectively. c-kit was expressed ubiquitously in all human immature oocytes, 3PN embryos and 3PN blastocysts. In the experiment of human 3PN embryos, compared with other groups, SCF group showed obviously higher rate of good quality at day 3, better rate of blastocyst formation at day 6 and higher rate of good quality blastocyst formation at day 6. Furthermore, we observed a higher ETV5 expression in SCF group than that in other groups. Similar results were also found in animal experiment. Interestingly, we also found a higher phosphorylation level of MEK/ERK signal molecule in mice embryos from SCF group than those from other groups. Moreover, inhibition of MEK/ERK signaling would remarkably impeded the mice