Effects of high concentrations of hyaluronan in culture medium on development and survival rates of fresh and frozen-thawed bovine embryos produced in vitro

Abstract

Hyaluronic acid (HA) is the main glycosaminoglycan present in follicular, oviductal and uterine fluids. The main functions of HA include dynamic processes that are mediated through interaction with extracellular matrix components, regulation of gene expression, cell proliferation and cell differentiation. HA increases the viscosity of solutions and also has several physiological functions, including regulation of water distribution and waterbinding capacity. The addition of 6 mg HA ml-1 to synthetic oviduct fluid (SOF; SOF-HA) culture medium on day 5 (IVF = day 0) significantly (P < 0.001) increased the viscosity of the medium in comparison with SOF culture medium containing BSA (SOF-BSA). On day 8, rate of blastocyst development in SOF-HA culture medium was significantly (P < 0.05) higher than in SOF-BSA culture medium (38.2 versus 29.3%). The number of trophectoderm cells and the total number of cells of expanded blastocysts cultured in the presence of HA were significantly (P < 0.01) higher in comparison with expanded blastocysts cultured in the presence of BSA (88.9 ± 7.3 versus 67.6 ± 3.0 and 130.1 ± 10.9 versus 104.8 ± 2.5, respectively). After freezing and thawing, the percentage of day 8 embryos that re-expanded and hatched when cultured with SOF-HA was greater than that of embryos cultured with SOF-BSA (11.3 and 10.5% versus 75.5 and 36.8%, respectively). After thawing, the ATP contents of in vivo-derived, SOF-HA and SOF-BSA expanded blastocysts were similar. The embryos cultured with HA showed less ultrastructural deviation and de-differentiation after freezing and thawing than the embryos cultured with BSA. This study demonstrates that HA improves the developmental capacity of bovine embryos under in vitro conditions and is warranted as a supplement for in vitro production of bovine embryos, particularly if they are to be cryopreserved.

In vitro bovine embryo production in a synthetic medium: Embryo development, cryosurvival, and establishment of pregnancy

“…It is involved in several processes mediated through interaction with matrix components, cell proliferation, and cell differentiation [35]. Hyaluronan and its receptors are thought to be involved in the regulation of GFs [36].…”

An auto-controlled prospective comparison of two embryos culture media (G III series versus ISM) for IVF and ICSI treatments

“…Subsequently, it has been demonstrated that hyaluronan has an important role in embryo culture media. Hyaluronan can substitute for albumin in culture media but what is perhaps more significant for human IVF applications is that the addition of hyaluronan to a culture medium containing albumin significantly increased development but also improved the cryosurvival of embryos [22,23]. In addition, recent randomized controlled trials in clinical IVF confirmed that elevating the levels of hyaluronan increased pregnancy and implantation rates, which was particularly evident in selected patient groups [24][25][26].…”

Derivation, growth and applications of human embryonic stem cells

“…1) which is probably due to the presence of hyaluronic acid (HA) in the second step and different growth factors such as LIF, insulin-like growth factor-II (IGF-II), and transforming growth factor b (TGFb) in BRL-medium (Stojkovic et al 1995). HA plays a very important role in early embryogenesis (Stojkovic et al 2003) and, when added to culture medium, HA increases the cell number of mouse (Gardner et al 1999, Figueiredo et al 2002 and bovine blastocysts (Stojkovic et al 2002). Added to serum-free medium, LIF increases the blastocyst rate, hatching rate and cell number of mammalian preimplantation embryos (Fry 1992, Dunglison et al 1996 but whether greater numbers of ICM cells in day 8 blastocysts allow more-efficient derivation of hES cells is difficult to say.…”