Addition of Recombinant Human Growth Hormone to In Vitro Maturation Medium of Bovine Oocytes

Abstract

The aim of this study was to increase the bovine embryonic development rate, adding recombinant human growth hormone (rhGH) to maturation medium of bovine oocytes. Oocytes were matured for 24 h in TCM 199 Earle's salts and five treatments were developed: T1, 0.01 IU/ml of recombinant human follicle stimulating hormone (rhFSH); T2, 0.01 IU/ml of rhFSH + 100 ng/ml of rhGH; T3, 0.01 IU/ml of rhFSH + 1000 ng/ml of rhGH; T4, 100 ng/ml of rhGH; and T5, 1000 ng/ml of rhGH at 39 degrees C and 5% of CO(2) in air and saturated humidity. In vitro fertilization from cumulus-oocyte complexes was conducted in TALP-Fert medium (18-22 h) and spermatozoa were selected by Percoll gradient. Zygotes were incubated in SOFaaci medium in 5% of CO(2) in air, 5% of O(2) at 39 degrees C and saturated humidity for 11 days. There was no statistical difference in cleavage rate and embryo production on day 7 and day 9 among treatments. However, the hatching rate increased significantly in the T4 and T5 treatments (11.0 and 12.8%, respectively), compared with the T1 treatment (4.6%) (p < 0.05). Therefore, the rhGH addition to the oocyte maturation medium showed beneficial effects on the hatching rate of in vitro-produced bovine embryos.

Growth Hormone and Reproduction: A Review of Endocrine and Autocrine/Paracrine Interactions

“…These studies were also able to use the GH-treated follicles in IVF protocols, resulting in the production of at least morulae [ 217 ] and in some cases live embryos [ 216 ]. Indeed, Izadyar et al [ 222 ] and Mtango et al [ 223 ] observed that the addition of GH to the IVM maturation medium enhanced the eventual number of cleaved embryos and blastocysts, while other studies observed similar numbers but increased quality [ 224 – 226 ]. Curiously, Shirazi et al [ 227 ] observed that GH and FSH coincubation during IVM actually decreased the blastocyst rate, whereas each hormone alone promoted blastocyst production.…”

“…The blastocyst must escape, or “hatch,” from this matrix before it can implant into the maternal endometrium [ 313 ]. GH improves the hatching rate in bovine [ 226 ] and murine [ 314 ] blastocyst populations. Increased production of matrix metalloproteinases (MMP) may potentially be involved, since these proteins play a role in implantation and are produced in response to GH (at least in liver) [ 315 ].…”

Preimplantation embryo metabolism and culture systems: experience from domestic animals and clinical implications

“…Moreira et al [144]; Bevers and Izadyar [145]; Kölle et al [146,147]; Pozzobon et al [148]; Kuzmina et al [149]; Velazquez et al [150,151]; Makarevich et al [152] IGF-I, IGF-II, FGF2, transforming growth factor beta1 (TGF β1 ), leukemia inhibitory factor (LIF) and CSF2, singly and in combination.…”

Multiple Effects of Growth Hormone in the Body: Is it Really the Hormone for Growth?

“…130 This is because the early blastocyst needs to escape from the zona pellucida that surrounds it, a protective matrix composed of glycoproteins and carbohydrates, before it can implant into the endometrium. GH improves the rate of this escaping in bovine, 134 and murine, 135 blastocyst populations. Therefore, GH facilitates implantation, perhaps by increasing the production of matrix metalloproteinases and also by selectively stimulating trophoblast cell proliferation, since these cells participate in blastocyst cavity formation and invasion of the maternal endometrium.…”