Comparison of cytoskeletal integrity, fertilization and developmental competence of oocytes vitrified before or after in vitro maturation in a porcine model

Porcine embryo production following in vitro fertilization and intracytoplasmic sperm injection from vitrified immature oocytes matured with a granulosa cell co-culture system

“…These results overcome the previously reported ones in different species such as swine [11,42] and ovine [13]. The results also demonstrate that the vitrification protocol, the Cryolock method, and the co-culture system are able to enhance not only IVM rates [5], but also IVF without affecting ED.…”

“…The establishment of oocyte cryopreservation procedures is of great importance in human assisted reproduction techniques, animal production for fertility and genetic improvement, including endangered animal species [8,11]. Successful vitrification can be determined by the meiotic stage of the oocyte.…”

Evaluation of the impact of vitrification on the actin cytoskeleton of in vitro matured ovine oocytes by means of Raman microspectroscopy

“…The debate on how vitrification procedures affect the microfilament network of the immature or mature oocytes has been reported in several studies [8,13,[17][18][19][20][21][38][39][40]. Consequences of vitrification/warming on the actin cytoskeleton depended on the CPAs used, the oocyte maturation stage and varied between species.…”

“…Several studies have shown that the exposure to cryoprotectants and the cold temperatures may lead to the disruption of microtubules and the change of the meiotic spindle morphology of mature oocytes [11][12][13][14][15][16]. Few reports focus on modifications caused by vitrification on the actin cytoskeleton [13,[17][18][19][20][21]. Actin is a major component of the cytoskeleton of the oocyte and it is present as the fibrous polymer, F-actin, in dynamic equilibrium with monomeric globular actin (G-actin).…”

“…The cytoskeleton network of the oocyte has a peculiar arrangement of microtubules, microfilaments and intermediate filaments and plays an important role during the maturation and the fertilization of the oocyte as well as in the early embryonic development [9,10]. Several studies have shown that the exposure to cryoprotectants and the cold temperatures may lead to the disruption of microtubules and the change of the meiotic spindle morphology of mature oocytes [11][12][13][14][15][16]. Few reports focus on modifications caused by vitrification on the actin cytoskeleton [13,[17][18][19][20][21].…”