75 EPIGENETIC EFFECTS OF VITRIFICATION ON PRONUCLEAR DOMESTIC CAT EMBRYOS

2015 ◽  
Vol 27 (1) ◽  
pp. 131 ◽  
Author(s):  
J. H. Galiguis ◽  
C. E. Pope ◽  
M. N. Biancardi ◽  
C. Dumas ◽  
G. Wang ◽  
...  

Vitrification remains a promising technique in the preservation of valuable genetic material; however, in the cat, success has varied. Live kittens have been produced from embryos vitrified at early cleavage stages, but phenotypic abnormalities in some kittens suggest possible epigenetic effects of the vitrification process. It has been reported that cryopreservation alters epigenetic events in somatic donor cells, which indirectly influences physical status of cloned offspring. However, extending post-warming in vitro culture of donor cells corrects these epigenetic modifications, resulting in normal embryos/clones. Accordingly, in the present study, vitrification was performed at the pronuclear stage to lengthen pretransfer culture time, and vitrified cat zygotes were assessed by analysing (1) histone acetylation/methylation, (2) global DNA methylation, (3) pluripotent gene expression, (4) in vitro development, and () in vivo viability. In vivo matured/IVF oocytes were vitrified in 15% dimethyl sulfoxide, 15% ethylene glycol, and 0.5 M sucrose at 16 h post-insemination (PI). After warming in 1.0 M sucrose at 38°C, embryos were fixed at 18 h or 40 h PI, and the nuclear intensity of either acetyl/dimethyl-H3K9 or 5-methylcytosine was determined by immunofluorescence. Results showed that at 18 h PI, mean H3K9ac intensity of vitrified embryos (11.8; n = 6) was higher than that of corresponding nonvitrified (fresh) controls (4.5; n = 6) and the fresh (3.2; n = 11) and vitrified (0.6; n = 7) 40-h groups (2-way ANOVA; P < 0.05). H3K9me2 in the fresh (36.9) and vitrified (32.5) 18-h embryos was similar but increased relative to both fresh (10.7) and vitrified (9.2) 40-h groups (P < 0.05). Mean DNA methylation (5MeC) in the fresh (31.6; n = 1) and vitrified (24.7; n = 3) 18-h groups was similar to that of the fresh 40-h group (19.8; n = 4) but higher than that of the vitrified 40-h group (15.0; n = 5; P < 0.05). To assess expression of POU5F1 and Nanog, qRT-PCR was performed on Day 8 blastocysts. Relative to controls (n = 9), mean POU5F1 and Nanog levels in vitrified blastocysts (n = 24) were 1.38- and 1.98-fold higher, respectively (one-way ANOVA; P > 0.05). In terms of in vitro development, Day 2 cleavage of vitrified zygotes (59%; n = 508) was similar to that of controls (66%; n = 340), but Day 8 blastocyst formation was reduced (9 v. 31%; t-test; P < 0.05). In vivo viability was assessed by oviducal transfer of 41 Day 1 embryos into 2 recipients. One pregnancy was established (50%), with 3 live kittens weighing 70, 79, and 131 g delivered without assistance on Day 65 of gestation. The 2 smaller kittens died within a few hours of birth, with the smallest exhibiting an umbilical hernia and organ exteriorization. The third kitten developed into a normal, healthy adult. In summary, mean H3K9me2, 5MeC, and POU5F1/Nanog expression of vitrified zygotes was similar to corresponding controls. H3K9ac increased at 18h PI as a result of vitrification, but was reduced after culture to 40 h PI. Although vitrified zygotes cleaved in vitro at rates similar to controls, blastocyst development was reduced. In vivo viability was demonstrated; however, postnatal survival of kittens produced was low.

2004 ◽  
Vol 16 (2) ◽  
pp. 202 ◽  
Author(s):  
W.F. Swanson ◽  
A.L. Manharth ◽  
J.B. Bond ◽  
H.L. Bateman ◽  
R.L. Krisher ◽  
...  

Domestic cat embryos typically are cultured in media formulated for somatic cells or embryos from rodents or livestock species. Under these conditions, blastocyst development has been inconsistent and delayed relative to embryos grown in vivo, and embryo viability following transfer has been low. Our goal is to systematically define the culture requirements of the feline embryo to improve embryo development and viability. The objective of this study was to determine the ionic (NaCl, KCl, KH2PO4, and CaCl2:MgSO4) preferences of domestic cat IVF embryos. Anestral female cats were injected (i.m.) with 150IU eCG followed 84h later by 100IUhCG. Oocytes were recovered via laparoscopic follicular aspiration approximately 24h post-hCG injection (Day 0). Semen was collected from one of two males by means of an artificial vagina and washed once in HEPES-buffered IVF medium. Mature cumulus-oocyte complexes were co-incubated with 2.5–5×105 motile sperm mL−1 in IVF medium (100mM NaCl, 4.0mM KCl, 1.0mM KH2 PO4, 2.0mM CaCl2, 1.0mM MgSO4-7H2O, 25.0mM NaHCO3, 3.0mM glucose, 0.1mM pyruvate, 6.0mM L-lactate, 1.0mM glutamine, 0.1mM taurine, 1×MEM nonessential amino acids, 50μgmL−1 gentamicin, and 4.0mgmL−1 BSA) for 19 to 22h in 6% CO2 in air (38.7°C). Cumulus cells were removed and embryos cultured (8–11 embryos/50μL drop; 6% CO2, 5% O2, 89% N2, 38.7°C) in media containing 100.0 or 120.0mM NaCl, 4.0 or 8.0mM KCl, 0.25 or 1.0mM KH2PO4, and 1.0mM:2.0mM or 2.0mM:1.0mM CaCl2:MgSO4 (2×2×2×2 factorial design). The remaining components of the culture medium were identical to the IVF medium (but w/o gentamicin). Development to the blastocyst stage by Day 6, metabolism (glycolysis and pyruvate) of each blastocyst, and final cell number (Hoechst 33342 staining) of all embryos were evaluated. Final cell number of cleaved embryos and development to the blastocyst stage were analyzed using analysis of variance in the GLIMMIX macro of SAS. A total of 236 oocytes were inseminated, yielding 128 cleaved embryos (54%), including 6 blastocysts (4.7% of cleaved embryos). Cell number was not (P&gt;0.05) affected by NaCl, KCl, or KH2PO4 concentrations, but tended (P=0.057) to be higher after culture in 2.0mM:1.0mM CaCl2:MgSO4. Treatments did not significantly affect (P&gt;0.05) development to the blastocyst stage, but numerically more blastocysts were produced in 100.0mM NaCl (4/6), 8.0mM KCl (5/6), or 1.0mM KH2PO4 (5/6). Both CaCl2:MgSO4 ratios resulted in 3 blastocysts. Blastocysts contained 61.08±5.1 (mean±SEM, n=6) cells and actively metabolized glucose (glycolysis, 3.7±0.8pmol/embryo/3h or 0.06±0.01pmol/cell/3h) and pyruvate (0.75±0.27pmol/embryo/3h or 0.013±0.005pmol/cell/3h). These results suggest that the ionic composition of culture media influences the in vitro development of cat IVF embryos. (Supported by NIH grant RR15388.)


2011 ◽  
Vol 23 (1) ◽  
pp. 142
Author(s):  
J. Galiguis ◽  
M. C. Gómez ◽  
C. E. Pope ◽  
B. L. Dresser ◽  
S. P. Leibo

Although considerable progress has been made in the development of successful methods for cryopreservation of embryos, oocytes are much less cryotolerant. There appears to be an inverse relationship between cryosurvival and intracellular lipid levels. For example, cat oocytes, which appear microscopically as coffee-coloured, nearly opaque spheres due to their high lipid content, are extremely sensitive to cryopreservation. Oocyte delipidation thus represents a potential approach to improving cryosurvival. The objectives of the present study were to examine 1) the effects of calcium (Ca2+, 0 v. 10 nM), FBS (0 v. 10%), and cytochalasin B (CB, 7.5 v. 20.0 μg mL–1) during mechanical delipidation by high-speed centrifugation on in vitro development of IVM cat oocytes, and 2) the influence of centrifugation, degree of lipid polarization (partial v. full), and co-culture with cat fetal fibroblasts (CFF) on in vitro development of vitrified IVM cat oocytes. In Experiment 1, oocytes were randomly allocated to each centrifugation medium and centrifuged at 12 000 × g for 20 min. Oocytes were then fertilized with epididymal sperm (motile sperm mL–1) and cultured until Day 8 (Pope et al. 2006 Theriogenology 66, 59–71). In Experiment 2, oocytes were centrifuged with the optimal centrifugation medium obtained in experiment 1, allocated to each treatment and vitrified in a solution of 15% DMSO, 15% ethylene glycol, and 18% sucrose (2008 Reprod. Fertil. Dev. 20, 188). Liquified oocytes were fertilized and cultured until Day 8. In both experiments, cleavage and degeneration rates were determined on Day 2 and blastocyst development on Day 8. Data were analysed by 2-way ANOVA and chi-square tests. In Experiment 1, of 939 oocytes that were centrifuged and fertilized, 40% of those treated in 0 nM Ca2+ cleaved and 22% developed into blastocysts, v. 33 and 6%, respectively, in 10 nM Ca2+ (P < 0.05). The respective cleavage and degeneration frequencies for oocytes treated in 10% FBS were 43 and 19% v. 19 and 3% in 0% FBS (P < 0.05). Cleavage and blastocyst development after treatment with 7.5 and 20.0 μg mL–1 CB were 36 and 15% v. 42 and 22%, respectively. In Experiment 2, 493 oocytes were vitrified/liquified and fertilized. The degeneration, cleavage, and blastocyst rates of non-centrifuged oocytes were 49, 21, and 0% v. 31 (P < 0.05), 38 (P < 0.05), and 7%, respectively, of centrifuged oocytes. Of centrifuged oocytes with partially extruded lipids, 34% degenerated, 34% cleaved, and 4% developed into blastocysts v. 29, 42, and 10%, respectively, of oocytes with fully extruded lipids. Degeneration, cleavage and blastocyst rates of co-cultured v. control oocytes were 18, 36, and 10%, v. 26 (P < 0.05), 34, and 3%, respectively. In summary, cryotolerance of domestic cat oocytes to vitrification was 1) affected by their lipid content, and 2) improved by mechanical reduction of intracellular lipids. When oocytes were fully delipidated in Ca2+-free medium containing 10% FBS and 20.0 μg mL–1 CB before vitrification and co-cultured after IVF with CFF, blastocyst development was similar to that of control, non-vitrified oocytes.


2013 ◽  
Vol 25 (1) ◽  
pp. 169 ◽  
Author(s):  
J. T. Kang ◽  
J. Y. Choi ◽  
S. J. Park ◽  
S. J. Kim ◽  
J. H. Moon ◽  
...  

Despite great advances in the field of cloning techniques, the efficiency of production of cloning animals is very low. Maybe the poor outcome of somatic cell nuclear transfer (SCNT) is thought to be a consequence of incomplete reprogramming of the donor cell or cloned embryos. The objective of this study was to investigate the effects of treatment with S-adenosylhomocysteine (SAH), the reversible nontoxic inhibitor of DNA methyltransferases (DNMT), on porcine female fibroblast donor cells and in vitro development of cloned embryos. We hypothesized that SAH targeting DNA methylation could alter chromatin configuration and turn it more amenable to reprogramming. Thus, the female fibroblast donor cells were cultured in media containing respective concentrations of SAH [0 (control), 0.1, 0.5, and 1 mM) for 2 passages. One-way ANOVA was used to determine significant differences in the data and a Tukey test was done to determine statistical differences among groups. Compared with nontreated controls, the cells treated with SAH, especially 1 mM, revealed significantly (P < 0.05) reduced global DNA methylation, proved by commercial kit and immunocytochemistry analysis, and elevation of transcript levels for X chromosome-linked genes (XIST and HPRT), estimated by real-time PCR analysis compared with the control group. It was suggested that treatment with SAH in female cells could make cells into more valuable donor cells for cloning. In another trial, cloned embryos using normal donor cells were cultured in media containing 1 mM SAH for 0 (control), 12, and 24 h after activation on different time interval of DNMT inhibition, transferred to PZM5 media, and subsequently cultured for 7 days. Treatment with SAH for 12 h resulted in 13.0 ± 1.9% blastocyst production, which was significantly greater than cloned embryos treated with SAH for 24 h (11.2 ± 2.1%) and control cloned embryos (9.1 ± 1.2%). It was suggested that the appropriate DNMT inhibition might have an important role in in vitro development of porcine SCNT, and improving effects on developmental competency of cloned embryos. We concluded that SAH induced global DNA demethylation that partially reactivated the X chromosome and that a hypomethylated genome may facilitate the nuclear reprogramming process. This study was supported by IPET (no. 311011-05-1-SB010), MKE (no. 10033839-2012-21), Institute for Veterinary Science, the BK21 program, and TS Corporation.


2007 ◽  
Vol 19 (1) ◽  
pp. 141
Author(s):  
S. Imsoonthornruksa ◽  
C. Lorthongpanich ◽  
K. Srirattana ◽  
N. Sripunya ◽  
C. Laowtammathron ◽  
...  

Domestic cat can serve as a valuable model for assisted reproductive techniques studies of endangered felid species. Therefore, this study was conducted to examine the effect of different manipulation medium on in vitro development of reconstructed domestic cat oocytes. The oocytes were recovered by slicing the ovaries of the cats that had been superstimulated with 200 IU eCG (Intervet, Boxmeer, The Netherlands). The procedures for SCNT were described previously (Lorthongpanich et al. 2004 Reprod. Fertil. Dev. 16, 149 abst). The manipulation medium for SCNT procedures was evaluated between HEPES-buffered TCM-199 (Sigma-Aldrich Corp., St Louis, MO, USA) + 10% FBS (199H) and Emcare embryo holding solution (ICPbio, Ltd., Auckland, New Zealand) (Emcare) during the denuding, enucleation, injection, activation, and holding steps. Parthenogenetic activation (PA) embryos were used as a control for both media. There was no significant difference in fusion rate when either 199H (63%) or Emcare (76%) was used. The cleavage, 8-cell, and morulae development rates of SCNT and PA were not significantly different when using either 199H or Emcare (Table 1). However, the blastocyst formation rates of SCNT and PA in Emcare (44% and 29%, respectively) were significantly greater than those of 199H (14% and 18%, respectively; P &lt; 0.05). These results indicated that the manipulation medium is important for SCNT blastocyst development. Table 1.In vitro development of cloned domestic cat and parthenogenetic activation of embryos from different manipulation media


2021 ◽  
Vol 22 (16) ◽  
pp. 8367
Author(s):  
Hien Lau ◽  
Shiri Li ◽  
Nicole Corrales ◽  
Samuel Rodriguez ◽  
Mohammadreza Mohammadi ◽  
...  

Pre-weaned porcine islets (PPIs) represent an unlimited source for islet transplantation but are functionally immature. We previously showed that necrostatin-1 (Nec-1) immediately after islet isolation enhanced the in vitro development of PPIs. Here, we examined the impact of Nec-1 on the in vivo function of PPIs after transplantation in diabetic mice. PPIs were isolated from pancreata of 8–15-day-old, pre-weaned pigs and cultured in media alone, or supplemented with Nec-1 (100 µM) on day 0 or on day 3 of culture (n = 5 for each group). On day 7, islet recovery, viability, oxygen consumption rate, insulin content, cellular composition, insulin secretion capacity, and transplant outcomes were evaluated. While islet viability and oxygen consumption rate remained high throughout 7-day tissue culture, Nec-1 supplementation on day 3 significantly improved islet recovery, insulin content, endocrine composition, GLUT2 expression, differentiation potential, proliferation capacity of endocrine cells, and insulin secretion. Adding Nec-1 on day 3 of tissue culture enhanced the islet recovery, proportion of delta cells, beta-cell differentiation and proliferation, and stimulation index. In vivo, this leads to shorter times to normoglycemia, better glycemic control, and higher circulating insulin. Our findings identify the novel time-dependent effects of Nec-1 supplementation on porcine islet quantity and quality prior to transplantation.


2000 ◽  
Vol 164 (6) ◽  
pp. 3047-3055 ◽  
Author(s):  
Dragana Jankovic ◽  
Marika C. Kullberg ◽  
Nancy Noben-Trauth ◽  
Patricia Caspar ◽  
William E. Paul ◽  
...  

2004 ◽  
Vol 16 (2) ◽  
pp. 154
Author(s):  
H.S. Park ◽  
M.Y. Lee ◽  
S.P. Hong ◽  
J.I. Jin ◽  
J.K. Park ◽  
...  

Recent techniques in somatic cell nuclear transfer (SCNT) have been widely used for animal research. In addition, SCNT techniques may allow for the rescue of endangered species. Despite efforts for wildlife preservation, however, some threatened or endangered wild animal species will likely become extinct. As a preliminary experiment of a series in wildlife research, we tried to identify an improved method for the production of more transferable NT embryos in goats. Mature donor animals of Korean native goats (20–25kg) were synchronized with a CIDR (type G; InterAg, New Zealand) vaginal implant for 10 days followed by a total of 8 twice daily injections of 70mg of FSH (Folltropine, London, Ontario, Canada) and 400IU of hCG (Chorulon, Intervet, Moxmeer, The Netherlands). Oocytes were then collected surgically by retograde oviduct flush or direct aspiration from ovarian follicles in vivo at 29–34h after hCG. Oocytes collected from follicles were matured in TCM-199 containing 10% FBS and hormones. Prepared ear skin cells from the goat were cultured in TCM-199 containing 10% FBS at 39°C, 5% CO2 in air, and confluent monolayers were obtained. Oocytes were enucleated and donor cells from serum starvation (0.5%) culture were fused through a single electric pulse (DC 2.36kvcm−1, 17μs), and then activated by a single electric pulse (AC 5vmm−1, 5s+DC 1.56kvcm−1, 30μs) or chemical treatment (5μgmL−1 ionomycin 5min−1, 1.9mM 6-DMAP/4h). Reconstructed oocytes were cultured in M16 medium with 10% goat serum (GS) for 6–7 days. Data were analyzed by chi-square test. In in vitro development, significantly (P&lt;0.05) more oocytes were cleaved (24/30, 80.0%) and developed (7/24, 29.2%) to morula or blastocyst stage, respectively, in NT oocytes activated by Iono + DMAP compared to electric stimulated oocytes (2/21, 40.0%; 0/2, 0%). There was a significant difference in in vitro development of NT embryos by the method of oocyte collection. Cleavage rate was higher (P&lt;0.05) in NT embryos from in vivo oocytes (23/28, 82.1%) than in in vitro matured oocytes (19/35, 54.3%), and further development to morula or blastocyst was also significantly (P&lt;0.05%) higher in NT embryos from in vivo oocytes (7/23, 30.4%) than in NT embryos from in vitro matured oocytes (0/19, 0%). When we compared NT embryos to parthenotes, developmental rate was not significantly different between NT embryos and parthenotes. These results strongly suggest that the in vivo oocytes will have superior developmental potential to oocytes matured in vitro. Table 1 Effect of different oocyte source on in vitro development following caprine SCNT


2017 ◽  
Vol 41 (3) ◽  
pp. 1255-1266 ◽  
Author(s):  
Jun-Xue Jin ◽  
Sanghoon Lee ◽  
Anukul Taweechaipaisankul ◽  
Geon A. Kim ◽  
Byeong Chun Lee

Background/Aims: Hypoacetylation caused by aberrant epigenetic nuclear reprogramming results in low efficiency of mammalian somatic cell nuclear transfer (SCNT). Many epigenetic remodeling drugs have been used in attempts to improve in vitro development of porcine SCNT embryos. In this study, we examined the effects of LAQ824, a structurally novel histone acetylase inhibitor, on the nuclear reprogramming and in vitro development of porcine SCNT embryos. Methods: LAQ824 treatment was supplemented during the culture of SCNT embryos. The reprogramming levels were measured by immunofluorescence and quantified by image J software. Relative expression levels of 18 genes were analyzed by quantitative real-time PCR. Results: 100 nM LAQ824 treatment of post-activation SCNT embryos for 24 h significantly improved the subsequent blastocyst formation rate. The LAQ824 treatment enhanced histone 3 lysine 9 (H3K9) levels, histone 4 lysine 12 (H4K12) levels, and reduced global DNA methylation levels as well as anti-5-methylcytosine (5-mC) at the pseudo-pronuclear and 2-cell stages. Furthermore, LAQ824 treatment positively regulated the mRNA expression of genes for histone acetylation (HAT1, HDAC1, 2, 3, and 6), DNA methylation (DNMT1, 3a and 3b), development (Pou5f1, Nanog, Sox2, and GLUT1) and apoptosis (Bax, Bcl2, Caspase 3 and Bak) in blastocysts. Conclusion: Optimum exposure (100 nM for 24 h) to LAQ824 post-activation improved the in vitro development of porcine SCNT embryos by enhancing levels of H3K9 and H4K12, reducing 5-mC, and regulating gene expression.


Author(s):  
Sara Mantero ◽  
Federica Boschetti

Bioreactors are powerful tools for in vitro development of engineered substitutes through controlled biological, physical, and mechanical culture conditions: bioreactor technology allows a closer in vitro replication of native tissues. One of bioreactors applications is the design of in vitro 3D tissue models as a bridge between 2D and in vivo models, allowing the application of 3R (replacement, reduction, refinement) principle. To this aim, bioreactors can be used to culture cells seeded on engineered scaffolds under in vivo-like conditions. Another key use of bioreactors is for perfusion decellularization of tissues and organs to be used as scaffolds. This contribution describes a dynamic stretching. bioreactor, imposing a mechanical stretching to the cultured constructs, allowing the development of skeletal muscle engineered constructs, and a decellularization bioreactor, designed for decellularization of blood vessels.


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