Royan Institute for Reproductive Biomedicine Research

Tehrān, Iran

Royan Institute for Reproductive Biomedicine Research

Tehrān, Iran
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Ebrahimi B.,Tarbiat Modares University | Valojerdi M.R.,Tarbiat Modares University | Valojerdi M.R.,Royan Institute for Reproductive Biomedicine Research | Eftekhari-Yazdi P.,Royan Institute for Reproductive Biomedicine Research | And 2 more authors.
Zygote | Year: 2012

Summary To determine the ultrastructural changes of sheep cumulus-oocyte complexes (COCs) following different methods of vitrification, good quality isolated COCs (GV stage) were randomly divided into the non-vitrified control, conventional straw, cryotop and solid surface vitrification groups. In both conventional and cryotop methods, vitrified COCs were respectively loaded by conventional straws and cryotops, and then plunged directly into liquid nitrogen (LN 2); whereas in the solid surface group, vitrified COCs were first loaded by cryotops and then cooled before plunging into 2. Post-warming survivability and ultrastructural changes of healthy COCs in the cryotop group especially in comparison with the conventional group revealed better viability rate and good preservation of the ooplasm organization. However in all vitrification groups except the cryotop group, mitochondria were clumped. Solely in the conventional straw group, the mitochondria showed different densities and were extremely distended. Moreover in the latter group, plenty of large irregular connected vesicles in the ooplasm were observed and in some parts their membrane ruptured. Also, in the conventional and solid surface vitrification groups, cumulus cells projections became retracted from the zona pellucida in some parts. In conclusion, the cryotop vitrification method as compared with other methods seems to have a good post-warming survivability and shows less deleterious effects on the ultrastructure of healthy vitrified-warmed sheep COCs. © 2011 Cambridge University Press.


Kyasari O.R.,Royan Institute for Reproductive Biomedicine Research | Kyasari O.R.,University of Tehran | Valojerdi M.R.,Royan Institute for Reproductive Biomedicine Research | Valojerdi M.R.,Tehran University of Medical Sciences | And 2 more authors.
Theriogenology | Year: 2012

The purpose of this study was to investigate the effects of somatic cells of cumulus origin (sCC) on gene expression and maturation of cumulus oocyte complexes (COCs) in vitro. Good quality (i.e., healthy-looking) isolated sheep COCs were randomly divided into two treatment groups: control (COC with no sCC) and coculture (COC with sCC). Nuclear maturation statuses of oocytes were assessed after 27 hours of in vitro culture. Moreover, the expression levels of growth differentiation factor 9 (GDF9), bone morphogenetic protein (BMP)15, BMP6, bone morphogenetic protein receptor II (BMPRII), activin like kinase 5 (ALK5) (transforming growth factor β receptor 1: TGFβR1), ALK6 (BMPR1b), activin A receptor, type IIB (ActRIIB), and ALK3 (BMPR1a), as well as hyaluronan synthase 2 (HAS2) and prostaglandin endoperoxide synthase 2 (Ptgs2) in the COCs were assessed in both treatment groups after 3 h and 27 h of culture. The results showed that the proportion of metaphase II (MII) stage oocytes was significantly higher in the coculture group compared with the controls (77.21% ± 1.17 vs. 67.49% ± 1.80; P < 0.05). The relative expressions of BMPRII, ALK6, and ActRIIB in control group and GDF9 and ActRIIB in coculture group showed significant differences during culture as assessed by real time polymerase chain reaction (P < 0.05). The mean expression levels of BMPRII, ALK5, ALK6, and ActRIIB mRNA were decreased in the coculture group compared with those in the control group after 27 h of culture (P < 0.05). In conclusion, we propose that in vitro maturation of sheep COCs alone disrupted the normal gene expression levels of both TGFβ ligands and receptors, and also reduced the maturation rate. Coculture with sCC enhanced the maturation rate of oocytes concomitantly with reduced gene expression levels of a number of TGFβ ligands and receptors. © 2012 Elsevier Inc.


Ebrahimi B.,Tehran University of Medical Sciences | Valojerdi M.R.,Tehran University of Medical Sciences | Valojerdi M.R.,Royan Institute for Reproductive Biomedicine Research | Eftekhari-Yazdi P.,Royan Institute for Reproductive Biomedicine Research | And 3 more authors.
Reproductive BioMedicine Online | Year: 2010

To determine the optimal vitrification conditions for sheep cumulus - oocyte complexes (COC), good-quality isolated COC were randomly divided into non-vitrified control, conventional straw, cryotop and solid-surface vitrification groups. In the conventional and cryotop methods, the vitrified COC were respectively loaded by conventional straw and cryotop, whereas in the solid-surface group, the vitrified COC were loaded by cryotop and then cooled before plunging in liquid nitrogen. The results indicated that the mean percentage of viability of vitrified - warmed COC was higher in both cryotop groups than that of the conventional group (83.84±2.85 and 78.56±1.72 versus 63.43±1.48%, P<0.05). In the cryotop group, although the mean percentage of oocyte maturation was similar to that in the control group (48.81±3.09 versus 51.94±3.01%), it was significantly higher than the other vitrification groups (48.81±3.09 versus 36.60±1.69 and 6.09±2.51%, respectively, P<0.05). However, the expression of maturation genes (GDF9, BMP15) was retarded after vitrification. Among the vitrification groups, the cryotop group had better expression. BMPRII was also expressed highly in the control, whereas ALK5 was similar in all groups. In conclusion, direct cryotop, when compared with other vitrification methods, seemed to be safe and could increase the viability, post-warming maturation and maturation-gene expression rates of sheep COC. © 2009, Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.


Tahaei L.S.,Royan Institute for Reproductive Biomedicine Research | Eimani H.,Royan Institute for Reproductive Biomedicine Research | Eimani H.,University of Tehran | Yazdi P.E.,Royan Institute for Reproductive Biomedicine Research | And 2 more authors.
Journal of Assisted Reproduction and Genetics | Year: 2011

Purpose: Evaluation of the all-trans retinoic acid (t-RA) effects on in vitro maturation (IVM) and in vitro fertilization (IVF) of immature mouse oocytes in the presence and absence of granulosa cell monolayer. Methods: Denuded oocytes isolated from mice ovaries and matured in IVM medium alone (Control I), IVM medium in the presence of granulosa cells (Control II), IVM medium with t-RA (Experimental I) and IVM medium simultaneously with t-RA and granulosa cells (Experimental II). After 24 h, matured oocytes were fertilized in T6 medium and their development was followed until the blastocyst stage. Metaphase II oocytes ploidy were evaluated by chromosome counting. Results: The t-RA group compared to the control groups showed no obvious abnormalities. Additionally maturation and embryo development rates significantly increased in the t-RA treated granulosa cell co-culture system. Conclusions: In conclusion, association of t-RA with granulosa cell co-culture during in vitro maturation increases meiosis resumption, formation of metaphase II oocytes, as well as 2-cell and blastocyst stage embryos. © 2011 Springer Science+Business Media, LLC.


PubMed | Royan Institute for Reproductive Biomedicine Research
Type: Journal Article | Journal: Theriogenology | Year: 2011

The purpose of this study was to investigate the effects of somatic cells of cumulus origin (sCC) on gene expression and maturation of cumulus oocyte complexes (COCs) in vitro. Good quality (i.e., healthy-looking) isolated sheep COCs were randomly divided into two treatment groups: control (COC with no sCC) and coculture (COC with sCC). Nuclear maturation statuses of oocytes were assessed after 27 hours of in vitro culture. Moreover, the expression levels of growth differentiation factor 9 (GDF9), bone morphogenetic protein (BMP)15, BMP6, bone morphogenetic protein receptor II (BMPRII), activin like kinase 5 (ALK5) (transforming growth factor receptor 1: TGFR1), ALK6 (BMPR1b), activin A receptor, type IIB (ActRIIB), and ALK3 (BMPR1a), as well as hyaluronan synthase 2 (HAS2) and prostaglandin endoperoxide synthase 2 (Ptgs2) in the COCs were assessed in both treatment groups after 3 h and 27 h of culture. The results showed that the proportion of metaphase II (MII) stage oocytes was significantly higher in the coculture group compared with the controls (77.21%1.17 vs. 67.49%1.80; P<0.05). The relative expressions of BMPRII, ALK6, and ActRIIB in control group and GDF9 and ActRIIB in coculture group showed significant differences during culture as assessed by real time polymerase chain reaction (P<0.05). The mean expression levels of BMPRII, ALK5, ALK6, and ActRIIB mRNA were decreased in the coculture group compared with those in the control group after 27 h of culture (P<0.05). In conclusion, we propose that in vitro maturation of sheep COCs alone disrupted the normal gene expression levels of both TGF ligands and receptors, and also reduced the maturation rate. Coculture with sCC enhanced the maturation rate of oocytes concomitantly with reduced gene expression levels of a number of TGF ligands and receptors.


PubMed | Royan Institute for Reproductive Biomedicine Research
Type: Journal Article | Journal: Journal of assisted reproduction and genetics | Year: 2011

Evaluation of the all-trans retinoic acid (t-RA) effects on in vitro maturation (IVM) and in vitro fertilization (IVF) of immature mouse oocytes in the presence and absence of granulosa cell monolayer.Denuded oocytes isolated from mice ovaries and matured in IVM medium alone (Control I), IVM medium in the presence of granulosa cells (Control II), IVM medium with t-RA (Experimental I) and IVM medium simultaneously with t-RA and granulosa cells (Experimental II). After 24h, matured oocytes were fertilized in T6 medium and their development was followed until the blastocyst stage. Metaphase II oocytes ploidy were evaluated by chromosome counting.The t-RA group compared to the control groups showed no obvious abnormalities. Additionally maturation and embryo development rates significantly increased in the t-RA treated granulosa cell co-culture system.In conclusion, association of t-RA with granulosa cell co-culture during in vitro maturation increases meiosis resumption, formation of metaphase II oocytes, as well as 2-cell and blastocyst stage embryos.

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