title: Vitrification of mouse MII oocytes: Developmental competency using paclitaxel.
abstract: OBJECTIVE
  Oocyte cryopreservation provides an important alternative for fertility preservation for women who will be treated with cytotoxic drugs. However, it can cause spindle disorganization of microtubules, putting the zygote at risk for aneuploidy. Paclitaxel is known to stabilize the microtubules that constitute the spindle. The aim of this study was to investigate the suitable concentration of paclitaxel for adding to the vitrification media to improve the developmental potential of post-thawed mature oocytes to blastocyst formation in mice.
  
  
  METHODS
  A total of 300 MII oocytes were retrieved from superovulated mice, and were divided into three groups of control, Experimental I, and Experimental II. Oocytes in Experimental I and Experimental II were cryopreserved in the presence of 0.5μM or 1μM of paclitaxel in vitrification media, respectively. After thawing, all oocytes were incubated in G-IVF medium for 1 hour. From each group,12 oocytes were selected for viability evaluation by Hoechst/propidium iodide nuclear staining. Standard in vitro fertilization was performed on the rest of the oocytes and embryo development was followed to the blastocyst stage.
  
  
  RESULTS
  Fertilization rate was not significantly different between the three groups. However, the cleavage rate (55%) in Experimental II group was significantly lower compared to Experimental I (88%) and control groups (83%). There was a detectable difference between the three groups at the blastocyst rate (Experimental I and control groups, p = 0.004; Experimental II vs. control and Experimental I, p < 0.001). The highest rates of parthenogenesis and arrest were in Experimental II (16% and 21%, respectively) compared with control (6% and 5%, respectively) and Experimental I (5% and 3%, respectively). There was also a significant decrease in viability rate of oocytes in Experimental II compared to the other groups.
  
  
  CONCLUSIONS
  A high concentration of paclitaxel, an anticancer drug, interrupted the mouse oocyte competency when supplemented to vitrification media. Consequently, the optimal concentration of this cytoskeleton stabilizer may improve the post-thawed developmental abilities of oocytes.
authors.affiliation: Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran; Department of Genetics, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Farzaneh
authors.initials: F
authors.lastname: Fesahat
authors.affiliation: Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Azita
authors.initials: A
authors.lastname: Faramarzi
authors.affiliation: Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Arezoo
authors.initials: A
authors.lastname: Khoradmehr
authors.affiliation: Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Marjan
authors.initials: M
authors.lastname: Omidi
authors.affiliation: Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Anbari
authors.affiliation: Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Electronic address: khalili59@hotmail.com.
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Khalili
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000494:pharmacology*; D001755:Blastocyst / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects*; D016009:Chi-Square Distribution; D015925:Cryopreservation; D047108:Embryonic Development / Q000187:drug effects*; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D008297:Male; D051379:Mice; D054315:Oocyte Retrieval; D009865:Oocytes / Q000187:drug effects*; D017239:Paclitaxel / Q000008:administration & dosage / Q000494:pharmacology*; D011897:Random Allocation
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D017239:Paclitaxel
keywords: embryo development; mouse; oocyte viability; paclitaxel; vitrification