Response of Immature and Mature Mouse Oocyte Spindle Structure to Oxidative Stress

Abstract

ObjectiveThe present study was undertaken to evaluate the effect of oxidative stress (OS) on the spindle structure of immature and mature oocytes induced by exogenous exposure to hydrogen peroxide during in vitro culture.DesignProspective, animal studyMaterials and methodsTable 1Percentage of mature and immature oocytes showing alterations in the MT following H2O2 exposureTable 2Analysis of CH between mature and immature groups following H2O2 exposureTable 2Analysis of CH between mature and immature groups following H2O2 exposureResultsResults of the alterations in MT are in Table 1 and CH analyses in Table 2. Compared with control, statistically significant differences were seen in both abnormal and missing microtubules category from both mature and immature oocytes following H2O2 exposure (P <0.05). An inverse trend was seen in the proportion of abnormal and missing microtubules in the mature and immature oocytes (P <0.05) following H2O2 exposure. Statistically significant differences were observed in both slightly abnormal and abnormal CH from mature and immature oocytes compared with control (P <0.05). However there were no differences in slightly abnormal and abnormal CH seen in both mature and immature oocytes.ConclusionMicrotubules in immature oocytes are more sensitive to OS compared to mature oocyte. Alterations in CH are comparable between mature and immature oocytes. Mature oocytes show more resistance to oxidative stress than immature oocytes. It is critical to have minimal exposure to OS conditions as the immature oocytes retrieved from the patient are subjected to subsequent in vitro maturation, in vitro fertilization, or oocyte freezing. ObjectiveThe present study was undertaken to evaluate the effect of oxidative stress (OS) on the spindle structure of immature and mature oocytes induced by exogenous exposure to hydrogen peroxide during in vitro culture. The present study was undertaken to evaluate the effect of oxidative stress (OS) on the spindle structure of immature and mature oocytes induced by exogenous exposure to hydrogen peroxide during in vitro culture. DesignProspective, animal study Prospective, animal study Materials and methodsTable 1Percentage of mature and immature oocytes showing alterations in the MT following H2O2 exposureTable 2Analysis of CH between mature and immature groups following H2O2 exposure ResultsResults of the alterations in MT are in Table 1 and CH analyses in Table 2. Compared with control, statistically significant differences were seen in both abnormal and missing microtubules category from both mature and immature oocytes following H2O2 exposure (P <0.05). An inverse trend was seen in the proportion of abnormal and missing microtubules in the mature and immature oocytes (P <0.05) following H2O2 exposure. Statistically significant differences were observed in both slightly abnormal and abnormal CH from mature and immature oocytes compared with control (P <0.05). However there were no differences in slightly abnormal and abnormal CH seen in both mature and immature oocytes. Results of the alterations in MT are in Table 1 and CH analyses in Table 2. Compared with control, statistically significant differences were seen in both abnormal and missing microtubules category from both mature and immature oocytes following H2O2 exposure (P <0.05). An inverse trend was seen in the proportion of abnormal and missing microtubules in the mature and immature oocytes (P <0.05) following H2O2 exposure. Statistically significant differences were observed in both slightly abnormal and abnormal CH from mature and immature oocytes compared with control (P <0.05). However there were no differences in slightly abnormal and abnormal CH seen in both mature and immature oocytes. ConclusionMicrotubules in immature oocytes are more sensitive to OS compared to mature oocyte. Alterations in CH are comparable between mature and immature oocytes. Mature oocytes show more resistance to oxidative stress than immature oocytes. It is critical to have minimal exposure to OS conditions as the immature oocytes retrieved from the patient are subjected to subsequent in vitro maturation, in vitro fertilization, or oocyte freezing. Microtubules in immature oocytes are more sensitive to OS compared to mature oocyte. Alterations in CH are comparable between mature and immature oocytes. Mature oocytes show more resistance to oxidative stress than immature oocytes. It is critical to have minimal exposure to OS conditions as the immature oocytes retrieved from the patient are subjected to subsequent in vitro maturation, in vitro fertilization, or oocyte freezing.