Anti-apoptotic effect of insulin-like growth factor (IGF)-I and its receptor in porcine preimplantation embryos derived from in vitro fertilization and somatic cell nuclear transfer.
Insulin-like growth factor (IGF)-I is a receptor-mediated autocrine and/or paracrine growth and/or survival factor for mammalian embryo development. It is known to promote the growth and development of mouse preimplantation embryos. The present study was designed to investigate the effects of IGF-I (50 ng/ml), anti-IGF-I receptor antibody (50 ng/ml) and their combination on porcine preimplantation embryo development. Furthermore, the mechanism underlying the embryotropic effects of IGF-I was evaluated by monitoring the incidence of apoptosis and expression of apoptosis-related genes. In both in vitro fertilized (IVF) and somatic cell nuclear transfer (SCNT) embryos, culturing with IGF-I increased the rate of blastocyst formation and this embryotrophic effect was neutralized by culturing with IGF-I along with anti-IGF-I receptor (IGF-IR) antibody. Culturing IVF and SCNT embryos with IGF-I significantly increased the number of total cells in blastocysts and decreased the number of apoptotic nuclei. These effects of IGF-I were also neutralized by culturing with IGF-I along with anti-IGF-IR antibody. Expression of the anti-apoptotic Bcl-2 gene was increased, while expression of the pro-apoptotic Bax was decreased in both IVF and SCNT embryos cultured with IGF-I. In both IVF and SCNT embryos, anti-IGF-IR antibody along with IGF-I neutralized the effect of IGF-I on expression of Bcl-2 and Bax genes. In conclusion, the present study demonstrated that IGF-I through its specific receptors improved the developmental competence of IVF and SCNT embryos by decreasing the incidence of apoptosis and regulating apoptosis-related genes in porcine preimplantation embryos.
Kim
Sue
S
Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, Seoul, Korea.
Lee
So Hyun
SH
Kim
Ji Hye
JH
Jeong
Yeon Woo
YW
Hashem
M A
MA
Koo
Ok Jae
OJ
Park
Sun Mi
SM
Lee
Eu Gine
EG
Hossein
M S
MS
Kang
Sung Keun
SK
Lee
Byeong Chun
BC
Hwang
Woo Suk
WS
D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism / Q000494:pharmacology; D001755:Blastocyst / Q000187:drug effects* / Q000378:metabolism; D002452:Cell Count; D046149:Embryo Culture Techniques / Q000379:methods; D047108:Embryonic Development / Q000187:drug effects; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006822:Hybrid Cells / Q000187:drug effects* / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D017526:Receptor, IGF Type 1 / Q000276:immunology / Q000502:physiology*; D013552:Swine / Q000196:embryology*
D000906:Antibodies; D051017:Apoptosis Regulatory Proteins; D007334:Insulin-Like Growth Factor I; D017526:Receptor, IGF Type 1