title: Insulinlike growth factor I improves yak (Bos grunniens) spermatozoa motility and the oocyte cleavage rate by modulating the expression of Bax and Bcl-2.
abstract: The aim of our present study was to examine the effects of insulinlike growth factor 1 (IGF-1) on yak sperm motility during in vitro capacitation and the relationship between the effects of IGF-1 on yak sperm motility and apoptosis was evaluated. Frozen-thawed yak spermatozoa were incubated at 38 °C for 1 hour in Tyrode's bicarbonate-buffered medium for sperm culture (Sp-TALP) with different concentrations (0, 50, 100, and 200 ng/mL) of IGF-1. In every treatment, the sperm motility was measured by a computer-assisted sperm analyzer system. The fertilizing ability of spermatozoa was evaluated on the basis of oocyte cleavage rate after insemination. The expression of Bax and Bcl-2 was examined by real-time polymerase chain reaction and Western blot for the messenger RNA and protein levels. It is interesting to note that IGF-1 improved yak spermatozoa motility and the cleavage rate of oocytes; these improvements were highest in the 100 ng/mL IGF-1 group, followed by the 200 ng/mL and 50 ng/mL groups, with the lowest improvements in motility and cleavage rates in groups without IGF-1. The expression level of Bax was downregulated by IGF-1, whereas Bcl-2 was upregulated. Both messenger RNA and Bax proteins were lowest in groups with 100 ng/mL IGF-1, where the Bcl-2 was the highest. Bax expression in the groups with IGF-1 was lower than that in the group without IGF-1, and Bcl-2 expression was higher in groups with IGF-1 than that in the group without IGF-1. In conclusion, this research reports that improvements in yak spermatozoa motility and the oocyte cleavage rate after the addition of IGF-I may be a result of the reduction of spermatozoa apoptosis rates by modulating the expression of Bax and Bcl-2.
authors.affiliation: Gansu Province Livestock Embryo Engineering Research Center, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China.
authors.forename: Yangyang
authors.initials: Y
authors.lastname: Pan
authors.affiliation: Gansu Province Livestock Embryo Engineering Research Center, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Cui
authors.affiliation: Faculty of Veterinary Sciences, Sindh Agriculture University, Tando Jam, Pakistan.
authors.forename: Abdul Rasheed
authors.initials: AR
authors.lastname: Baloch
authors.affiliation: Gansu Province Livestock Embryo Engineering Research Center, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China.
authors.forename: Jiangfeng
authors.initials: J
authors.lastname: Fan
authors.affiliation: Gansu Province Livestock Embryo Engineering Research Center, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China.
authors.forename: Junfeng
authors.initials: J
authors.lastname: He
authors.affiliation: Gansu Province Livestock Embryo Engineering Research Center, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China.
authors.forename: Guyue
authors.initials: G
authors.lastname: Li
authors.affiliation: Gansu Province Livestock Embryo Engineering Research Center, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China.
authors.forename: Hongfei
authors.initials: H
authors.lastname: Zheng
authors.affiliation: Gansu Province Livestock Embryo Engineering Research Center, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China.
authors.forename: Yifu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Gansu Province Livestock Embryo Engineering Research Center, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Lv
authors.affiliation: Gansu Province Livestock Embryo Engineering Research Center, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China. Electronic address: sjyu@163.com.
authors.forename: Sijiu
authors.initials: S
authors.lastname: Yu
mesh_terms: D000818:Animals; D002417:Cattle / Q000502:physiology*; D005786:Gene Expression Regulation / Q000187:drug effects; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D009865:Oocytes / Q000187:drug effects*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D013075:Sperm Capacitation / Q000187:drug effects; D013081:Sperm Motility / Q000187:drug effects*; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism*
chemical_list: D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D051028:bcl-2-Associated X Protein; D007334:Insulin-Like Growth Factor I
keywords: Bax; Bcl-2; Insulinlike growth factor 1; Motility; Spermatozoon; Yak