title: Distribution pattern of cytoplasmic organelles, spindle integrity, oxidative stress, octamer-binding transcription factor 4 (Oct4) expression and developmental potential of oocytes following multiple superovulation.
abstract: The aim of the present study was to determine the effects of repeated superovulation on oocyte quality and embryo developmental potential. Female Swiss albino mice were injected with 5IU pregnant mare's serum gonadotropin followed 48h by 10IU human chorionic gonadotropin. Mice were superovulated up to four times with a gap of 7 days between each superovulation cycle. Ovarian weight increased significantly with an increasing number of superovulation cycles. Although the first stimulation cycle resulted in a threefold increase in the number of oocytes, the number of oocytes decreased gradually after subsequent stimulations. Increased cytoplasmic fragmentation, abnormal mitochondrial distribution, aggregation of Golgi apparatus, spindle damage, increased intracellular oxidative stress and a decrease in expression of octamer-binding transcription factor 4 (Oct4) expression were observed in these oocytes. Further, embryos derived from mice subjected to multiple stimulation cycles exhibited a low blastocyst rate, decreased hatching rate and increased apoptosis in blastocysts. In conclusion, the present study demonstrates that repeated superovulation adversely affects mouse oocyte quality by altering the distribution of cytoplasmic organelles, increasing oxidative stress and decreasing Oct4 expression, resulting in poor developmental potential of the embryos.
authors.affiliation: Division of Clinical Embryology, Department of Obstetrics and Gynecology, Kasturba Medical College, Manipal University, Manipal, 576104, India.
authors.forename: Guruprasad
authors.initials: G
authors.lastname: Kalthur
authors.affiliation: Division of Clinical Embryology, Department of Obstetrics and Gynecology, Kasturba Medical College, Manipal University, Manipal, 576104, India.
authors.forename: Sujith Raj
authors.initials: SR
authors.lastname: Salian
authors.affiliation: Division of Clinical Embryology, Department of Obstetrics and Gynecology, Kasturba Medical College, Manipal University, Manipal, 576104, India.
authors.forename: Ramya
authors.initials: R
authors.lastname: Nair
authors.affiliation: Division of Clinical Embryology, Department of Obstetrics and Gynecology, Kasturba Medical College, Manipal University, Manipal, 576104, India.
authors.forename: Jemey
authors.initials: J
authors.lastname: Mathew
authors.affiliation: Division of Clinical Embryology, Department of Obstetrics and Gynecology, Kasturba Medical College, Manipal University, Manipal, 576104, India.
authors.forename: Satish Kumar
authors.initials: SK
authors.lastname: Adiga
authors.affiliation: Department of Anatomy, Kasturba Medical College, Manipal University, Manipal, 576104, India.
authors.forename: Sneha Guruprasad
authors.initials: SG
authors.lastname: Kalthur
authors.affiliation: Genome Stability Laboratory, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore.
authors.forename: Dimphy
authors.initials: D
authors.lastname: Zeegers
authors.affiliation: Genome Stability Laboratory, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore.
authors.forename: M Prakash
authors.initials: MP
authors.lastname: Hande
mesh_terms: D000818:Animals; D001755:Blastocyst; D005260:Female; D006064:Gonadotropins, Equine / Q000008:administration & dosage*; D006736:Horses; D006801:Humans; D051379:Mice; D050814:Octamer Transcription Factor-3 / Q000378:metabolism*; D009865:Oocytes / Q000166:cytology*; D015388:Organelles; D018384:Oxidative Stress; D011247:Pregnancy; D008941:Spindle Apparatus; D013480:Superovulation
chemical_list: D006064:Gonadotropins, Equine; D050814:Octamer Transcription Factor-3; C494174:Pou5f1 protein, mouse