Birth of normal calves after intracytoplasmic sperm injection of bovine oocytes: a methodological approach

Horiuchi, Toshitaka; Emuta, Chie; Yamauchi, Yasuhiro; Oikawa, Toshinori; Numabe, Takashi; Yanagimachi, Ryuzo

doi:10.1016/s0093-691x(01)00701-4

Cited by 83 publications

(79 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This blastocyst yield is comparable to or even higher than those in many reports where bovine oocytes harvested from freshly collected ovaries were used for ICSI [8,10,11,[13][14][15][16]. Simultaneously with the ICSI experiments in the present study, high blastocyst yield (40 ± 3%, 90/223) was obtained after routine 225 IVF protocol, suggesting that oocytes harvested from stored ovaries carry sufficient in vitro developmental potential after IVF and ICSI if they were subjected to appropriate activation regimen.…”

Section: Discussionsupporting

confidence: 63%

“…The ICSI was performed with a piezo-driven micromanipulator (PMAS-CT150; PrimeTech, Ibaraki, Japan), according to the method described previously [11]. Briefly, single spermatozoon was immobilized by applying several piezo pulses to the midpiece before being aspirated tail first into a blunt-ended injection pipette with an outer diameter of 7-9 µm.…”

Section: Intracytoplasmic Sperm Injection (Icsi) 115mentioning

confidence: 99%

“…The ICSI procedure has resulted in birth of live offspring in many species [5]. Since the first attempt of bovine ICSI [6], the developmental potential of the ICSI 45 oocytes into blastocysts in vitro or live calves in vivo still low, unstable and far from satisfactory regardless of the numerous efforts [7][8][9][10][11][12][13][14][15][16]. Beside the technical difficulties caused by darkness of the ooplasm, large size of the sperm heads, and elasticity and toughness of the oolemma, the inability of the mechanical stimulation and/or the injected spermatozoon itself to induce proper oocyte activation after ICSI [17] may be responsible for this low blastocyst yields.…”

Section: Introduction 40mentioning

confidence: 99%

“…This hypothesis is supported by the low blastocyst yields after ICSI without any exogenous activation stimuli [8,10,11,[13][14][15][16]. To improve 55 the blastocyst yields after bovine ICSI, additional exogenous activation stimuli that induce intracellular calcium spike such as direct current [19], calcium ionophore [20], ionomycin [8,13,14,16,17] or ethanol [9][10][11]15,16] have been applied. However, the monotonic calcium increase triggered by these stimuli [21,22] was insufficient to completely inactivate the MPF due to re-accumulation of the cyclin B [23] and brought the oocytes to arrest again at the M-III stage 60 [17,23,24].…”

Section: Introduction 40mentioning

confidence: 99%

See 3 more Smart Citations

A combined treatment of ionomycin with ethanol improves blastocyst development of bovine oocytes harvested from stored ovaries and microinjected with spermatozoa

et al. 2009

View full text Add to dashboard Cite

Regardless of the presence of sperm-borne oocyte-activating factors, activation of bovine oocytes with exogenous activation stimuli is required for further development after intracytoplasmic sperm injection (ICSI). The present study was designed to develop a new activation regimen for improving the blastocyst yield after ICSI of bovine oocytes harvested from ovaries stored at 10-12 oC for 24 h. Following ICSI, oocytes were treated with 5 μM ionomycin for 5 min, 7% ethanol for 5 or 10 min, ionomycin followed by ethanol (5 or 10 min), ionomycin followed by 10 µg/mL Cycloheximide for 5 h, or ionomycin followed by 1.9 mM 6-dimethylaminopurine for 3 h. Across the activation regimens, the cleavage rates of ICSI oocytes (45-77%) were higher than those of parthenogenetically activated oocytes (11-21%; P<0.05). Activating the ICSI oocytes with ionomycin plus ethanol improved the blastocyst yield (29-30%) comparing to the non-treated oocytes (12%; P<0.05) but the other regimens did not (9-18%; P>0.05). The higher blastocyst yields were due to increasing the proportion of ICSI oocytes that passed through the early postfertilization events until cleavage. None of the regimens have any adverse effect on the quality of the blastocysts regarding the total cell number or the proportion of the inner cell mass cells. Thus, a new activation regimen composed from two triggers for single calcium increase has been proven effective to improve the blastocyst yield after bovine ICSI using oocytes harvested from stored ovaries.Dear Dr. John P. Kastelic, Thank you very much for prompt reply and accepting our manuscript for publication in Theriogenology. We have replied for each comment from Co-editor and the reviewer-2 in pointby-point basis.Sincerely yours, Shinichi Hochi (Corresponding author)Hany Abdalla (First author)Co-editor 1-P value has been added to the Abstract (Lines 27,29).2-The number of the references in Introduction section has been reduced. Reviewer #21-Regarding omitting the two groups (5 min ethanol group and ionomycin followed by 5 min ethanol group); We do not think that the presence of these two groups causes any difficulty to recognize the superiority of ionomycin and ethanol combination. Since activation of 7% ethanol for 5 min 4 hr after ICSI is a commonly applied method for bovine ICSI, presence of such group must be important to declare the superiority of the new combination (ionomycin and ethanol) over the methods of ethanol alone under the same experimental circumstance regarding oocyte quality, injection skill, culture condition, and so on. For the ionomycin followed by 5 min ethanol, the efficiency of this method to improve the cleavage and the blastocyst yield was similar to that of ionomycin followed by 10 min ethanol, making it possible to choose the method in which oocytes are exposed to minimum exogenous stimuli. Tables 1 and 2. 2-The time of 2 nd polar body detection has been added in footnote of 15Running head: Bovine oocyte activation after ICSI * Manuscript 2 AbstractRegardless of the pres...

show abstract

Section: Discussionsupporting

confidence: 63%

Section: Intracytoplasmic Sperm Injection (Icsi) 115mentioning

confidence: 99%

Section: Introduction 40mentioning

confidence: 99%

Section: Introduction 40mentioning

confidence: 99%

See 2 more Smart Citations

A combined treatment of ionomycin with ethanol improves blastocyst development of bovine oocytes harvested from stored ovaries and microinjected with spermatozoa

et al. 2009

View full text Add to dashboard Cite

show abstract

“…To overcome this problem, bovine ICSI oocytes have been treated to induce intracellular calcium spike with a direct current pulse(s) (Hwang et al 2000), calcium ionophore (Keskintepe & Brackett 2000), ionomycin (Rho et al 1998; Galli et al 2003; Oikawa et al 2005; Abdalla et al 2009) or ethanol (Horiuchi et al 2002; Oikawa et al 2005; Abdalla et al 2009). Because these stimuli do not induce long‐lasting oscillations, they have been combined with other chemicals, such as cycloheximide (Galli et al 2003) or 6‐dimethylaminopurine (Rho et al 1998; Oikawa et al 2005) that interfere with either the re‐synthesis or the activation of the metaphase‐promoting factor (MPF), respectively.…”

Section: Chemical Treatment In Bovine Icsimentioning

confidence: 99%

Microtubule assembly crucial to bovine embryonic development in assisted reproductive technologies

Hochi

2016

Animal Science Journal

View full text Add to dashboard Cite

Centrosome integrity and microtubule network are crucial to the events around fertilization, including pronuclear development, migration and fusion, and the first mitotic division. The present review highlights the importance of bull spermatozoal centrosomes to function as a microtubule‐organizing center for successful fertilization and the subsequent embryonic development. Spermatozoal centrosomes need to be blended with ooplasmic pericentriolar materials accurately to nucleate and organize the sperm aster. Dysfunction of the spermatozoal centrosomes is associated with fertilization failure, which has been overcome with supplemental stimuli for oocyte activation following intracytoplasmic sperm injection in humans. Even though the spermatozoal centrosomes are functionally intact, abnormal sperm aster formation was frequently observed in vitrified‐warmed bovine oocytes, with delayed pronuclear development and migration. Treatment of the post‐warm oocytes with Rho‐associated coiled‐coil kinase inhibitor or α‐tocopherol inhibited the incidence of the abnormal aster formation, resulting in higher blastocyst yields following in vitro fertilization and culture. Thus, understanding of centrosomal function made it possible to improve the performance of advanced reproductive technologies.

show abstract

Interactions of sperm perinuclear theca with the oocyte: Implications for oocyte activation, anti‐polyspermy defense, and assisted reproduction

Šutovský

Manandhar

et al. 2003

Microscopy Res & Technique

144

104

View full text Add to dashboard Cite

Perinuclear theca (PT) is the cytoskeletal coat of mammalian sperm nucleus that is removed from the sperm head at fertilization. PT harbors the sperm borne, oocyte-activating factor (SOAF), a yet-to-be-characterized substance responsible for triggering the signaling cascade of oocyte activation, thought to be dependent on intra-oocyte calcium release. The present article reviews the current knowledge on the biogenesis and molecular composition of sperm PT. Possible functions of sperm PT during natural and assisted fertilization, and in the initiation of embryonic development are discussed. Furthermore, evidence is provided that SOAF is transferred from the sperm PT to oocyte cytoplasm through the internalization and rapid solubilization of the post-acrosomal PT. It is shown that during natural fertilization the sperm PT dissolves in the oocyte cytoplasm concomitantly with sperm nuclear decondensation and the initiation of pronuclear development. SOAF activity is preserved in the differentially extracted sperm heads only if the integrity of PT is maintained. After intracytoplasmic sperm injection (ICSI), activation occurs only in those oocytes in which the injected spermatozoon displays complete or partial dissolution of PT. In the latter case, the residual PT of the sub-acrosomal and/or post-acrosomal sperm region may persist on the apical surface of the sperm nucleus/male pronucleus and may cause a delay or arrest of zygotic development. We propose that the sperm PT harbors SOAF in the post-acrosomal sheath, as this is the first part of the sperm cytosol to enter the oocyte cytoplasm and its disassembly appears sufficient to initiate the early events of oocyte activation. Dissolution of the sub-acrosomal part of the PT, on the other hand, appears necessary to insure complete DNA decondensation in the internalized sperm nucleus and initiate DNA synthesis of both pronuclei. The release of the SOAF from the sperm head into oocyte cytoplasm at fertilization ultimately leads to the activation of oocyte mechanism including the completion of the meiotic cell cycle, pronuclear development and anti-polyspermy defense.

show abstract

Birth of normal calves after intracytoplasmic sperm injection of bovine oocytes: a methodological approach

Cited by 83 publications

References 39 publications

A combined treatment of ionomycin with ethanol improves blastocyst development of bovine oocytes harvested from stored ovaries and microinjected with spermatozoa

A combined treatment of ionomycin with ethanol improves blastocyst development of bovine oocytes harvested from stored ovaries and microinjected with spermatozoa

Microtubule assembly crucial to bovine embryonic development in assisted reproductive technologies

Interactions of sperm perinuclear theca with the oocyte: Implications for oocyte activation, anti‐polyspermy defense, and assisted reproduction

Contact Info

Product

Resources

About