Polyvinyl alcohol addition to freezing extender can improve the post-thaw quality, longevity and in vitro fertility of ram epididymal spermatozoa

Recovering and cryopreserving epididymal spermatozoa are suitable methods for preserving the genetic potential of livestock and endangered species. Regarding encouraging reports on the use of polyvinyl alcohol (PVA) in cryopreserving various cell types, we conducted this study to examine the impact of PVA on the post-thaw quality, longevity, and in vitro fertility of ram epididymal sperm. In the first experiment, ram epididymal spermatozoa were frozen in extenders containing 6 % glycerol and 0, 0.5, 1, 2, 5, 10, or 15 mg/ml of PVA. Polyvinyl alcohol at concentrations of 0.5, 1, and 2 mg/ml improved the motility and functional membrane integrity (FMI) of the sperm compared with the control group (P < 0.05). In the second experiment, we investigated whether PVA could partially substitute glycerol in the freezing extender. PVA was added at 0, 0.5, 1, and 2 mg/ml to the extenders containing 1 % or 2 % glycerol. After thawing, the sperm motility parameters of the group containing 1 mg/ml PVA and 2 % glycerol were significantly higher than those of the un-supplemented groups (P < 0.05). In the third experiment, the effect of PVA on the post-thaw sperm longevity were examined. Sperm were frozen in 3 extenders: one containing 6 % glycerol and 1 mg/ml PVA (Gly6P1), another containing 2 % glycerol and 1 mg/ml PVA (Gly2P1), and a control extender with 6 % glycerol. After thawing, the quality of the sperm was evaluated. Sperm were then diluted in human tubal fluid (HTF) and incubated at 37 °C for 3 h. Afterwards, the quality of the sperm was evaluated once more. The presence of PVA in the freezing extender improved motility parameters and FMI. Additionally, PVA-containing groups had lower proportions of capacitated and acrosome reacted sperm compared with the control group (P < 0.05). The Gly6P1 group performed better than the other two groups (P < 0.05). In the fourth experiment, sperm from the Gly6P1 and Control groups were used in the IVF process immediately after thawing (T0) and after a 3-h incubation at 37 °C in HTF (T3). Cleavage, blastocyst and hatching rates in both groups were similar at T0, but they were lower in the Control group at T3 (P < 0.05). In conclusion, PVA as an additive to the freezing extender significantly improves post-thaw motility, viability, acrosome integrity, longevity, and fertile lifespan of ram epididymal spermatozoa.

Effect of Intra-ovarian Injection of Mesenchymal Stem Cells or its Conditioned Media on Repeated OPU-IVEP Outcomes in Jersey Heifers and Its Relationship with Follicular Fluid Inflammatory Markers

Background

Repeated Ovum Pick Up (OPU) could have a detrimental effect on ovarian function, reducing In Vitro Embryo Production (IVEP). The present study examined the therapeutic effect of adipose-derived Mesenchymal Stem Cells (MSCs) or its Conditioned Medium (ConM) on ovarian trauma following repeated OPU. Resolvin E1 (RvE1) and Interleukin-12 (IL-12) were investigated as biomarkers.

Methods

Jersey heifers (n=8) experienced 11 OPU sessions including 5 pre-treatment and 6 treatment sessions. Heifers received intra-ovarian administration of MSCs or ConM (right ovary) and Dulbecco's Modified Phosphate Buffer Saline (DMPBS; left ovary) after OPU in sessions 5 and 8 and 2 weeks after session 11. The concentrations of RvE1 and IL-12 in follicular fluid was evaluated on sessions 1, 5, 6, 9, and 4 weeks after session 11. Following each OPU session, the IVEP parameters were recorded.

Results

Intra-ovarian administration of MSCs, ConM, and DMPBS did not affect IVEP parameters (p>0.05). The concentration of IL-12 in follicular fluid increased at the last session of pre-treatment (Session 5; p<0.05) and remained elevated throughout the treatment period. There was no correlation between IL-12 and IVEP parameters (p>0.05). However, RvE1 remained relatively high during the pre-treatment and decreased toward the end of treatment period (p<0.05). This in turn was associated with decline in some IVEP parameters (p<0.05).

Conclusion

Intra-ovarian administration of MSCs or ConM during repeated OPU did not enhance IVEP outcomes in Bos taurus heifers. The positive association between RvE1 and some of IVEP parameters could nominate RvE1 as a promising biomarker to predict IVEP parameters following repeated OPU.

Sperm and oocyte as carriers for bovine viral diarrhoea virus biotypes during in vitro fertilization

Bovine viral diarrhoea virus (BVDV) is an important viral agent causing the reproductive failure in cattle. The objectives of the study were to assess the role of male and female gametes, as carriers of cytopathic (CP) and non-cytopathic (NCP) BVDV to embryonic cells during in vitro fertilization. In this respect, sperm and oocytes were separately exposed to concentrations of 104.5 or 105.5 TCID50 /mL CP and NCP BVDV, for 2 h before fertilization. After washing, the intact gametes with the infected gametes were inseminated. Seven days post-fertilization, the virus-exposed embryos were examined for presence of the viral genome by RT-PCR. One-way anova with post-hoc Tukey's HSD test and an independent samples t-test were used to compare within and between groups, respectively. The results presented a significant decrease in the blastocyst rates for CP-infected groups than NCP-infected groups (p ≤ .01). Compared to the controls and the infected oocyte groups, the cleavage rates of the infected sperm groups (NCP and CP BVDV) were significantly reduced both in low (104.5 TCID50 /mL) and high (105.5 TCID50 /mL) titres of the virus (p ≤ .01). The proportion of embryos which was developed to blastocyst stages was significantly lower for CP and NCP-infected groups than the control groups (p ≤ .001). According to the molecular results, all samples of the retarded/degenerated embryos (at least one blastocyst within each one) in CP and NCP groups, one sample (at least one blastocyst in that) within a CP-infected group, and six samples (at least one blastocyst in each one of those) of NCP-infected groups contained the viral nucleic acid. Likewise, the results of viral enrichment showed all reactions in which RT-PCR were positive induced CPEs in MDBK monolayers. In conclusion, it is clear that CP and NCP BVDV were able to traverse zona pellucida during fertilization, and they had also negative effects on embryo development.

Higher Improvement of Cardiac Function Following Myocardial Infarction using Menstrual Blood Stromal/Stem Cells (MenSCs) Suspended in Conditioned Medium versus Conditioned Medium Alone in Rat Model

Background

To evaluate the efficiency of Menstrual blood Stromal/Stem Cells (MenSCs) administration in Myocardial Infarction (MI), the effects of MenSCs and their derived conditioned Medium (CM) on cardiac function in MI rat model was assessed.

Methods

Animals were divided into four groups including sham group, MI group, MenSCs derived CM group (CM group), and MenSCs suspended in CM (MenSCs+CM) group. The injection of different groups was carried out 30 min after ligation of left anterior descending coronary artery into the infarct border zone.

Results

The results showed a significant reduction in scar size after injection of MenSCs+CM compared to MI group. Ejection fraction and fractional shortening of MenSCs+CM group were higher than CM and MI group at day 28. Administration of MenSCs+CM led to much more survival of cardiomyocytes, and prevention of meta-plastic development. Moreover, human mitochondrial transfer from MenSCs to cardiomyocytes was seen in group treated by MenSCs+CM. Indeed, MenSCs+CM treatment evoked nuclear factor-κB (NF-κB) down-regulation more than other treatments.

Conclusion

MenSCs+CM treatment could significantly ameliorate cardiac function by different mechanisms including inhibition of cartilaginous metaplasia, inhibition of NF-κB and mitochondrial transfer.

Bioactive Materials Derived from Menstrual Blood Stem Cells Enhance the Quality of In Vitro Bovine Embryos

Backgrounds: The aim of this study was to determine whether the addition of bioactive materials derived from Menstrual Blood Stem Cells (MenSCs) to the oocyte maturation medium may improve the quality of bovine embryos in vitro.   Methods: MenSCs were collected from 6 healthy women (between 26 and 36 years old) and after 3 days of culture, their bioactive materials were frozen. The bovine Cumulus-Oocyte-Complexes (COCs) were aspirated from ovarian slaughterhouse and the oocytes with more than three layers of cumulus cells were cultured in vitro in media supplemented with (treatment) and without (control) 10% MenSCs’ bioactive materials. After IVM/IVF, the presumptive zygotes were cultured for 8 days.   Results: The blastocyst rate on day 8 in treatment group was higher than control (40.2±1.9 vs. 23±4.2.3, p=0.001). The ratio of Trophectoderm (TE) and Inner Cell Mass (ICM) (ICM/TE) cells was also greater in treatment group compared to control (30.3±2 vs. 14.9±1; p=0.001). The re-expansion of vitrified blastocysts, 24 hours after warming, in treatment group was higher than control (93.3±2.5 vs. 66.2±8.8; p=0.01). The expression of some genes related to pluripotency and implantation (OCT4, CDX2, and IFNT) were increased in treatment group compared to control (p<0/05).   Conclusion: In conclusion, the addition of MenSCs’ bioactive materials during in vitro maturation of bovine oocytes could improve the quantity and quality of bovine IVP embryos. Also, the expression of some genes associated with pluripotency and implantation in the blastocyst would be increased.

Bioactive Materials Derived from Menstrual Blood Stem Cells Enhance the Quality of In Vitro Bovine Embryos

Backgrounds

The aim of this study was to determine whether the addition of bioactive materials derived from Menstrual Blood Stem Cells (MenSCs) to the oocyte maturation medium may improve the quality of bovine embryos in vitro.

Methods

MenSCs were collected from 6 healthy women (between 26 and 36 years old) and after 3 days of culture, their bioactive materials were frozen. The bovine Cumulus-Oocyte-Complexes (COCs) were aspirated from ovarian slaughterhouse and the oocytes with more than three layers of cumulus cells were cultured in vitro in media supplemented with (treatment) and without (control) 10% MenSCs' bioactive materials. After IVM/IVF, the presumptive zygotes were cultured for 8 days.

Results

The blastocyst rate on day 8 in treatment group was higher than control (40.2±1.9 vs. 23±4.2.3, p=0.001). The ratio of Trophectoderm (TE) and Inner Cell Mass (ICM) (ICM/TE) cells was also greater in treatment group compared to control (30.3±2 vs. 14.9±1; p=0.001). The re-expansion of vitrified blastocysts, 24 hours after warming, in treatment group was higher than control (93.3±2.5 vs. 66.2±8.8; p=0.01). The expression of some genes related to pluripotency and implantation (OCT4, CDX2, and IFNT) were increased in treatment group compared to control (p<0/05).

Conclusion

In conclusion, the addition of MenSCs' bioactive materials during in vitro maturation of bovine oocytes could improve the quantity and quality of bovine IVP embryos. Also, the expression of some genes associated with pluripotency and implantation in the blastocyst would be increased.

Human amniotic membrane stem cells' conditioned medium has better support for in-vitro production of bovine embryos than FBS

Apart from oocyte quality, the media used has a significant effect on the production and quality of blastocysts produced in vitro. This study was designed to evaluate the replacement of serum with human amniotic membrane stem cells' conditioned medium (hAMSCs-CM) during bovine embryo culture on the quantity and quality of produced blastocysts. The in-vitro-produced embryos on the third day of IVC were randomly divided into the following culture groups: SOFaa + 5% FBS (Control), SOFaa + 5% hAMSCs-CM (5% CM), SOFaa + 2.5% hAMSCs-CM + 2.5% FBS (2.5% CM) and SOFaa + hAMSC co-culture (co-culture). The blastocyst and hatching rates, blastocyst cells number (the number of trophectoderm, inner cell mass and total cells), and the expression of some developmentally important genes (OCT4, PLAC8 and COX2 genes) in the treated groups, especially in the 5% CM, compared to the control had improved (p < .05). No significant difference was observed between groups for viability and hatching rate in vitrified-warmed blastocysts. Due to the positive effect of hAMSCs' conditioned medium (hAMSCs-CM) on blastocyst production, as well as its ease of preparation and the need to avoid the transmission of microbial contamination to the culture medium, hAMSCs-CM can be used as a suitable alternative to FBS during 3 to 8 days of bovine embryo culture.

The effect of chemical treatment of the sheep embryo zona pellucida on the ability of blastocysts to hatch after vitrification and warming

BACKGROUND

The embryo release from the zona pellucida is of prerequisites of successful implantation.

OBJECTIVES

Regarding the negative impact of embryo cryopreservation on the blastocysts hatchability, the aim of the present study was to investigate the effects of treating embryonic zona pellucida with pronase or acidic Tyrode's solution (ATS) before morula formation on the viability, freezability, and hatchability of vitrified-warmed resulted blastocysts.

METHODS

In the first experiment, the zona pellucida of 3- and 4-day-old embryos were treated with the above compounds for 30 or 45 s. Then, the competency of the treated embryos to reach to blastocyst stage and the hatchability of resulting blastocysts were investigated. In the second experiment, the cryo-survivability and hatching rate of blastocysts resulting from 3-day-old embryos treated with pronase and ATS for 30 s were tested.

RESULTS

In the first experiment and in contrast to the 45 s exposure, 30-s exposure of embryos to pronase or ATS did not have negative effect on the viability and development of embryos to blastocyst stage. In the second experiment, the freezability of blastocysts derived from 3-day-old embryos treated with pronase and ATS for 30 s was not different from that of the control group. However, the hatching rate of the pronase group was significantly higher than that of the control group.

CONCLUSION

The results of the present study showed that reducing the thickness of zona pellucida of sheep embryos with pronase had no negative effect on the developmental competency and freezability of the treated embryos and improved the hatchability of vitrified-warmed blastocysts.

The effect of CRISPR constructs microinjection on the expression of developmental genes in Rag1 knocked-out mice embryo

Despite all the advances in the production of transgenic mice, the production efficiency of these animal models is still low. Given that the expression of developmental genes has a critical role in growth and development of embryo, we determined the expression pattern of pluripotency, trophectoderm and imprinting genes in the Rag1 (recombination-activating gene 1) knocked-out blastocysts resulting from microinjection of CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9) constructs into the zygote cytoplasm of C57bl6 mice. Following microinjection, the embryos were cultured and the gene expression of developed blastocysts and natural blastocysts (Sham and control groups) were evaluated using real-time PCR. The agarose gel to confirm the deletion in the Rag1 gene in Rag1 knocked-out blastocyst. Our results showed that the expression of trophectoderm genes (-TEAD-4 and Cdx2), pluripotency genes (Nanog and Oct-4) and imprinting gene (H19) in the Rag1 knocked-out group was significantly lower compared with the embryos obtained from Natural fertilization. According to these findings, manipulation, embryo culture and microinjection of CRISPR constructs into the zygote cytoplasm of mice led to reduced expression of imprinting, pluripotency and trophectoderm genes. Therefore, the Rag1 knocked-out embryos produced by the CRISPR/Cas9 system are of low quality, which reduces the chances of live birth in these animals and may cause various abnormalities in fetuses.

H19/Igf2 Expression and Methylation of Histone 3 in Mice Chimeric Blastocysts

Background

Currently, the efficient production of chimeric mice and their survival are still challenging. Recent researches have indicated that preimplantation embryo culture media and manipulation lead to abnormal methylation of histone in the H19/Igf2 promotor region and consequently alter their gene expression pattern. This investigation was designed to evaluate the relationship between the methylation state of histone H3 and H19/Igf2 expression in mice chimeric blastocysts.

Methods

Mouse 129/Sv embryonic stem cells (mESCs) expressing the green fluorescent protein (mESCs-GFP) were injected into the perivitelline space of 2.5 days post-coitis (dpc) embryos (C57BL/6) using a micromanipulator. H3K4 and H3K9 methylation, and H19 and Igf2 expression was measured by immunocytochemistry and q-PCR, respectively, in blastocysts.

Results

Histone H3 trimethylation in H3K4 and H3K9 in chimeric blastocysts was significantly less and greater, respectively (p< 0.05), than in controls. H19 expression was significantly less (p< 0.05), while Igf2 expression was less, but not significantly so, in chimeric than in control blastocysts.

Conclusion

Our results showed, that the alteration ofH3K4me3 and H3K9me3 methylation, change H19/Igf2 expression in chimeric blastocysts.

A systematic review of the behaviours associated with depression in people with severe-profound intellectual disability

The assessment of depression in people with severe to profound intellectual disability (severe-profound ID) is challenging, primarily due to inability to report internal states such as mood, feelings of worthlessness and suicidal ideation. This group also commonly presents with challenging behaviours (e.g. aggression and self-injury) with debate about whether these behaviours should be considered 'depressive equivalents' or are sensitive for, but not specific to, depression in severe-profound ID. We conducted a systematic review exploring behaviours associated with depression and low mood in individuals with severe-profound ID. The review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (2009) guidelines. Three electronic databases were searched (Embase, PsycINFO and Ovid MEDLINE), and 13 studies were included and rated for quality. Few studies were rated as having high methodological quality. Behaviours captured by standard diagnostic schemes for depression (e.g. Diagnostic and Statistical Manual of Mental Disorders and International Classification of Diseases) showed a relationship with depression in severe-profound ID, including the two core symptoms (depressed affect and anhedonia), as well as irritability, sleep disturbance, psychomotor agitation, reduced appetite and fatigue. Challenging behaviours such as aggression, self-injury, temper tantrums, screaming and disruptive behaviour were associated with depression. Challenging behaviours show a robust relationship with depression. Whilst these behaviours may suggest an underlying depression, study limitations warrant caution in labelling them as 'depressive equivalents'. These limitations include not controlling for potential confounds (autism, other affective disorders and pain) and bias associated with comparing depressed/non-depressed groups on the same behavioural criteria used to initially diagnose and separate these groups. Future studies that use depressive measures designed for ID populations, which control for confounds and which explore low mood irrespective of psychiatric diagnosis, are warranted to better delineate the behaviours associated with depression in this population (PROSPERO 2018: CRD42018103244).

Histone Modifications of H3K4me3, H3K9me3 and Lineage Gene Expressions in Chimeric Mouse Embryo

OBJECTIVE

Chimeric animal exhibits less viability and more fetal and placental abnormalities than normal animal. This study was aimed to determine the impact of mouse embryonic stem cells (mESCs) injection into the mouse embryos on H3K9me3 and H3K4me3 and cell lineage gene expressions in chimeric blastocysts.

MATERIALS AND METHODS

In our experiment, at the first step, incorporation of the GFP positive mESCs (GFP-mESCs) 129/Sv into the inner cell mass (ICM) of pre-compacted and compacted morula stage embryos was compared. At the second and third steps, H3K4me3 and H3K9me3 status as well as the expression of Oct4, Nanog, Tead4, and Cdx2 genes were determined in the following groups: i. In vitro blastocyst derived from In vivo morula subjected to mESCs injection (blast/chimeric), ii. In vivo derived blastocyst (blast/In vivo), iii. In vitro blastocyst derived from culture of morula In vivo (blast/morula), and iv. In vitro blastocyst derived from morula In vivo subjected to sham injection (blast/sham).

RESULTS

Subzonal injection of GFP-mESCs at the pre-compacted embryos produced more chimeric blastocysts than compacted embryos (P<0.05). The number of trophectoderm (TE), ICM, ICM/TE and total cells in chimeric blastocysts were less than the corresponding numbers in blastocysts derived from other groups (P<0.05). In ICM and TE of chimeric blastocysts, the levels of H3K4me3 and H3K9me3 were respectively decreased and increased compared to the blastocysts of the other groups (P<0.05). Expressions of Oct4, Nanog and Tead4 were decreased in chimeric blastocysts compared to the blastocysts of the other groups (P<0.05), while this was not observed for Cdx2.

CONCLUSION

In the present study, embryo compaction significantly reduced the rate of incorporation of injected mESCs into the ICM. Moreover, in chimeric blastocysts, the levels of H3K9me3 and H3K4me3 were altered. In addition, the expressions of pluripotency and cell fate genes were decreased compared to blastocysts of the other groups.

Effects of cryopreservation on stallion sperm protamine messenger RNAs

Protamines substitute DNA-binding histones during late spermatogenesis in sperm nucleus. Stallion sperm contains all three variants of these arginine-rich and positively charged nuclear proteins (P1, P2 and P3). Two variants of protamine-2, that is P2 and P3, constitute approximately 15% of the entire protamine content. Also, the ratio of protamine-1 to protamine-2 varies among different mammalian species, and abnormal protamine ratios and protamine content are correlated with male infertility. In this study, changes in protamine mRNA abundance for all three protamines were investigated in stallion sperm during cryopreservation. Twelve ejaculates were collected from six sexually mature stallions. Sperm samples were divided into two parts for total mRNA extraction: one as fresh and the other as cryopreserved sample. Levels of three protamine transcripts were determined by real-time reverse transcriptase polymerase chain reaction. Results of relative expression showed that cryopreservation can significantly alter protamine transcripts: protamine 2 was downregulated, while protamine 3 was upregulated in cryopreserved samples relative to the control. Changes in protamine 1 were not significant after cryopreservation. This study is the first to evaluate changes in mRNA abundance of protamine genes in stallion sperm following cryopreservation. Such evaluations are important in finding transcriptomic markers for success in fertilization and assisted reproductive techniques.

The Anti-apoptotic Mechanism of Metformin Against Apoptosis Induced by Ionizing Radiation in Human Peripheral Blood Mononuclear Cells

BACKGROUND

In a previous article, we showed that metformin (MET) can reduce ionizing radiation (IR) induced apoptosis in human peripheral blood mononuclear cells. However, the anti-apoptotic mechanism of MET against IR remains unclear. The present study attempts to investigate the mechanism of action of MET in limiting X-ray induced apoptosis in human peripheral blood mononuclear cells.

MATERIAL AND METHODS

Mononuclear cells were treated with MET for 2 hours and irradiated with 6 MV X-rays. The gene expression levels of BAX, CASP3 and BCL2 were determined 24 hours post irradiation using real time quantitative polymerase chain reaction (qPCR) technique. Furthermore, the protein levels of BAX, CASP3 and BCL2 were analyzed by Western blotting assay.

RESULTS

Radiation exposure increased the expressions of BAX and CASP3 genes, and decreased the expression of BCL2 gene in mononuclear cells. Conversely, an increase in BCL2 gene expression along with a decrease in BAX and CASP3 genes expression was observed in MET plus irradiated mononuclear cells. It was found that radiation increased BAX/BCL2 ratio, while MET pretreatment reduced these ratios. Also, treatment with MET without irradiation did not change the expressions of BAX, CASP3 and BCL2 genes. On the other hand, downregulated expression of BCL2 protein and upregulated expressions of BAX and CASP3 proteins were found in 2 Gy irradiated mononuclear cells, while pretreatment with MET significantly reversed this tendency.

CONCLUSION

These results suggest that MET can protect mononuclear cells against apoptosis induced by IR through induction of cellular anti-apoptotic signaling.Key words: ionizing radiation - metformin - apoptosis - genes - proteins - blood cells.

Antioxidants and glycine can improve the developmental competence of vitrified/warmed ovine immature oocytes

Despite the numerous potential applications of oocyte cryopreservation, the poor success rate has limited its practical applications. In livestock, particularly in ovine, the oocytes have low developmental competence following vitrification/warming process. Considering the occurrence of osmotic and oxidative stresses during the vitrification/warming process, the application of antioxidants and osmolytes may improve the developmental competence of vitrified/warmed oocytes. In the present study, we aimed to evaluate the effects of the addition of ascorbic acid (AA) and N-acetyl cysteine (NAC) as antioxidants and glycine as an organic osmolyte either to the vitrification/warming solutions (VWS) or to the IVM medium on the developmental competence of vitrified/warmed ovine germinal vesicle stage oocytes. The survival rate in the vitrified groups was significantly lower than fresh ones. In vitrified/warmed oocytes, there was no significant difference in survival rate between supplemented and non-supplemented groups. The addition of AA and/or NAC to the VWS or IVM medium and adding glycine to the IVM medium reduced the proportion of apoptotic oocytes and fragmented embryos, which was reflected as an increase in the proportions of metaphase II stage oocytes and blastocyst production. The best result was achieved by supplementing the IVM medium with NAC. In our study condition, antioxidants and glycine could improve the developmental competence of vitrified/warmed ovine immature oocytes, especially when added during IVM.

Efficient Production of Biallelic RAG1 Knockout Mouse Embryonic Stem Cell Using CRISPR/Cas9

Background

Recombination Activating Genes (RAG) mutated embryonic stem cells are (ES) cells which are unable to perform V (D) J recombination. These cells can be used for generation of immunodeficient mouse. Creating biallelic mutations by CRISPR/Cas9 genome editing has emerged as a powerful technique to generate site-specific mutations in different sequences.

Objectives

The main purposes of this study were to achieve complete knock-out of RAG1 gene by investigating the nature of mutations in mutant mESC and to generate RAG1 knock-out mESCs containing homozygous indels with the aim of creating desired and specific RAG-1 -/- mutant mouse in a shorter period of time.

Materials and Methods

Here, we first utilized CRISPR/Cas9 system to target RAG1/RAG2 genes in NIH3T3 cells to test the activity and efficiency of our CRISPR system. Then we used the system for targeting RAG1 gene in mouse embryonic stem cell (mESCs) to generate knock-out embryonic stem cells. This method combined with highly active single guide RNA (sgRNA) is an efficient way to produce new RAG1-knockout mESCs in the selected regions of early coding DNA sequence, approximately between nucleotide c. 512-c. 513 and nucleotide c. 725-c. 726 of RAG1 coding sequence that had not been targeted previously.

Results

CRISPR gene editing resulted in a multitude of engineered homozygous and compound heterozygous mutations, including both in-frame and out-of-frame indels in 92% of mES cell clones. Most of the mutations generated by CRISPR/Cas9 system were out-of-frame, resulting in a complete gene knockout. In addition, 59% of the mutant ES cell clones carried out-of-frame homozygous indel mutations. The RAG1-knockout mESC clones retained normal morphology and pluripotent gene expression.

Conclusions

Our study demonstrated that CRISPR/Cas9 system can efficiently create biallelic indels containing both homozygous and compound heterozygous RAG1 mutations in about 92% of the mutant mESC clones. The 59% of mutant ES cell clones carried out-of-frame homozygous indel mutations.

Sericin Ameliorates the Capacitation State and Chromatin Integrity of Frozen-Thawed Stallion Spermatozoa by Reducing Oxidative Stress

BACKGROUND

In the process of sperm cryopreservation, apart from cryoinjury, the production of Reactive Oxygen Species (ROS) can adversely affect the integrity of chromatin and cellular membranes. Addition of natural antioxidants to freezing medium is an approach to reduce the destructive effects of ROS on sperm.

METHODS

In this study, during 60 min of cooling process, the ejaculates of five stallions were diluted in the following media: INRA 82 medium as Control (C), INRA 82 medium supplemented with 0.25% Sericin (S), INRA 82 medium supplemented with 1.5 mM Glutathione (G), and INRA 82 medium supplemented with 0.25% Sericin+1.5 mM Glutathione (S+G).

RESULTS

In the frozen/thawed sericin supplemented group, while the integrity of DNA and the activity of catalase and Glutathione Peroxidase (GPx) were increased, the lipid peroxidation and midpieceab normality decreased, compared with other groups (p<0.05). The proportions of sperms with abnormal head in group S and the sperm with distal droplet in G and S+G groups decreased, compared with group C (p<0.05). In CTC assay, the percentage of capacitated spermatozoa in treatment groups was lower than control (p<0.01).

CONCLUSION

In conclusion, the presence of sericin in freezing medium of stallion semen could improve sperm DNA integrity and its resistance to ROS and lipid peroxidation.

In Vitro Pre-validation of Gene Editing by CRISPR/Cas9 Ribonucleoprotein

BACKGROUND

The CRISPR/Cas9 genome editing system is a powerful and simple gene editing method. The format of the CRISPR components is one of the important factors in targeting efficiency. Compared to plasmid or mRNA (IVTs) format, using the CRISPR/Cas9 system as Cas9-crRNA-tracrRNA RNP format is more efficient and rapid, especially in minimizing some of the pitfalls of CRISPR-mediated gene editing. In addition to efficient in vivo applications of the CRISPR RNP format in a variety of cell types and organisms, another advantage of this approach is usability for in vitro applications in which the crRNAs in the tracrRNA-crRNA structure guides the Mg2+-dependent RNAdirected DNA endonuclease to introduce double-strand breaks at specific sites in DNA.

METHODS

Here, Cas9-crRNA-tracrRNA RNP system was used to test the designed crRNAs for in vitro DNA cleavage by Cas9 protein in RAG1, RAG2 and IL2RG genes.

RESULTS

The results of cleavage reveal theCas9-crRNA-tracrRNA RNP system is a rapid and efficient way to pre-validate the efficiency of CRISPR cleavage with crRNAs designed for RAG1, RAG2 and IL2RG genes.

CONCLUSION

one step in vitro cleavage of DNA by CRISPR/Cas9 ribonucleoprotein complex can be used to pre-validate the functionality and relative efficiency of CRISPR system for targeting genes.

CRISPR/Cas9 System for Efficient Genome Editing and Targeting in the Mouse NIH/3T3 Cells

BACKGROUND

The Clustered, Regularly Interspaced, Short Palindromic Repeats (CRIS-PR) and CRISPR-associated protein (Cas) system has been used as a powerful tool for genome engineering. In this study, the application of this system is reported for targeting Rag genes to produce mutant mouse NIH/3T3 cell line. The Rag1 and Rag2 genes are essential for generation of mature B and T lymphocytes. Disruption of Rag genes causes disease like Severe Combined Immunodeficiency syndrome (SCID). Here, the efficiency and specificity of CRISPR system were tested with highly active sgRNAs to generate novel mutations in the NIH/3T3 mouse cell line.

METHODS

Four single guide RNAs were designed to target sequences in the coding region of the Rag1 and Rag2 genes. Four sgRNA-CAS9 plasmids were tested to target Rag1 and Rag2.

RESULTS

Based on T7 endonuclease assay and sequencing analysis, the expression of sgRNAs targeting two sites in Rag1 resulted in deletion of the intervening DNA fragment. The expression of sgRNAs with Cas9 targeting two sites in Rag2 gene resulted in indel mutations at both sites. In this report, fragment deletion in Rag1 gene was detected in about 50% of transfected cells.

CONCLUSION

Therefore, CRISPR/Cas9 system can be highly efficient and specific when gRNAs are designed rationally and provides a powerful approach for genetic engineering of cells and model animals.

Mouse preantral follicle growth in 3D co-culture system using human menstrual blood mesenchymal stem cell

Follicle culture provides a condition which can help investigators to evaluate various aspects of ovarian follicle growth and development and impact of different components and supplementations as well as presumably application of follicle culture approach in fertility preservation procedures. Mesenchymal Stem Cells (MSCs), particularly those isolated from menstrual blood has the potential to be used as a tool for improvement of fertility. In the current study, a 3D co-culture system with mice preantral follicles and human Menstrual Blood Mesenchymal Stem Cells (MenSCs) using either collagen or alginate beads was designed to investigate whether this system allows better preantral follicles growth and development. Results showed that MenSCs increase the indices of follicular growth including survival rate, diameter, and antrum formation as well as the rate of in vitro maturation (IVM) in both collagen and alginates beads. Although statistically not significant, alginate was found to be superior in terms of supporting survival rate and antrum formation. Hormone assay demonstrated that the amount of secreted 17 β-estradiol and progesterone in both 3D systems increased dramatically after 12 days, with the highest levels in system employing MenSCs. Data also demonstrated that relative expression of studied genes increased for Bmp15 and Gdf9 and decreased for Mater when follicles were cultured in the presence of MenSCs. Collectively, results of the present study showed that MenSCs could improve indices of follicular growth and maturation in vitro. Further studies are needed before a clinical application of MenSCs-induced IVM is considered.

The effect of amniotic membrane stem cells as donor nucleus on gene expression in reconstructed bovine oocytes

Nuclear reprogramming of a differentiated cell in somatic cell nuclear transfer (SCNT) is a major concern in cloning procedures. Indeed, the nucleus of the donor cell often fails to express the genes which are a prerequisite for normal early embryo development. This study was aimed to evaluate the developmental competence and the expression pattern of some reprogramming related genes in bovine cloned embryos reconstructed with amniotic membrane stem cells (AMSCs) in comparison with those reconstructed with mesenchymal stem cells (MSCs) and adult fibroblasts (AF) as well as with in vitro fertilized (IVF) oocytes. In vitro matured abattoir-derived oocytes were considered as recipients and a hand-made cloning technique was employed for oocyte enucleation and nuclear transfer (NT) procedures. The expression pattern of genes involved in self-renewal and pluripotency (POU5F1, SOX2, NANOG), imprinting (IGF2, IGF2R), DNA methylation (DNMT1, DNMT3A), histone deacetylation (HDAC2), and apoptosis (BAX, BCL2) were evaluated in NT and IVF derived embryos. Despite the insignificant difference in cleavage rate between reconstructed and IVF oocytes, the blastocyst rate in the IVF group was higher than that of other groups. Among reconstructed oocytes, a higher blastocysts rate was observed in MSC-NT and AMSCs-NT derived embryos that were significantly higher than AF-NT derived ones. There were more similarities in the expression pattern of pluripotency and epigenetic modification genes between MSC-NT and IVF derived blastocysts compared with other groups. In conclusion, considering developmental competence, AMSCs, as alternative donors in SCNT procedure, like MSCs, were prone to have more advantage compared with AF.

Reconstruction of mammalian oocytes by germinal vesicle transfer: A systematic review

Nuclear transfer procedures have been recently applied for clinical and research targets as a novel assisted reproductive technique and were used for increasing the oocyte activity during its growth and maturation. In this review, we summarized the nuclear transfer technique for germinal vesicle stage oocytes to reconstruct the maturation of them. Our study covered publications between 1966 and August 2017. In result utilized germinal vesicle transfer techniques, fusion, and fertilization survival rate on five different mammalian species are discussed, regarding their potential clinical application. It seems that with a study on this method, there is real hope for effective treatments of old oocytes or oocytes containing mitochondrial problems in the near future.

Evidence of Oocyte Polarity in Bovine; Implications for Intracytoplasmic Sperm Injection and Somatic Cell Nuclear Transfer

Objective

We recently demonstrated spatial regionalization of maternal transcripts and proteins within unfertilized ovine oocyte. Here, we investigated the likelihood of oocyte polarity for the first time in bovine.

Materials and Methods

In this experimental study, in vitro matured bovine oocytes were used for manual bisection [into oocyte halve that were near-to (HNS) and far-from (FS) spindle] or trisection [into MII-spindle (S), the spindle-side half (NS), and the distal half unassociated with the spindle (FS)]. Prepared pools of oocyte substructures were used for comparative quantitative real-time polymerase chain reaction (RT-qPCR). To map the possible preferential sperm entry point (SEP), the spatial relationship between SEP and MII-spindle was measured 5 hours post-fertilization.

Results

The proportional amount of maternal mRNA in S oocyte fragment was estimated to be 6 to 11-fold higher than NS and FS counterparts. The relative abundances of Nanog, Oct4, Fgf4 and Tead4 were significantly higher in HNS oocyte fragment compared t0 FS. The relative abundances of Ctnb, Carm1, Rex1, Sox2 and Cdx2 were comparable between HNS and NS oocyte fragments. FS oocyte fragment possessed significantly higher transcripts of Gata4 compared to HNS. The distribution of certain transcripts related to pluripotency and lineage commitment were different depending upon the region of the oocyte; either enriched at S (Tead4, Nanog, Ctnb and Sox2), NS (Oct4), or FS (Gata6). The SEP in almost (90%) fertilized oocytes was located in MII-hemisphere.

Conclusion

The observation of spatial restriction of mRNAs and SEP within MII-oocyte may indicate that the principal forces of oocyte polarity are evolutionary conserved. This may in turn highlight the need for refinements in the methodology of intracytoplasmic sperm injection (where a sperm is injected far from the MII-spindle) and somatic cell nuclear transfer (where a major amount of regulative mRNAs that are associated with MIIspindle is removed during enucleation).

The melatonin immunomodulatory actions in radiotherapy

Radiotherapy has a key role in cancer treatment in more than half of patients with cancer. The management of severe side effects of this treatment modality is a limiting factor to appropriate treatment. Immune system responses play a pivotal role in many of the early and late side effects of radiation. Moreover, immune cells have a significant role in tumor response to radiotherapy, such as angiogenesis and tumor growth. Melatonin as a potent antioxidant has shown appropriate immune regulatory properties that may ameliorate toxicity induced by radiation in various organs. These effects are mediated through various modulatory effects of melatonin in different levels of tissue reaction to ionizing radiation. The effects on the DNA repair system, antioxidant enzymes, immune cells, cytokines secretion, transcription factors, and protein kinases are most important. Moreover, anti-cancer properties of melatonin may increase the therapeutic ratio of radiotherapy. Clinical applications of this agent for the management of malignancies such as breast cancer have shown promising results. It seems anti-proliferative, anti-angiogenesis, and stimulation or suppression of some immune cell responses are the main anti-tumor effects of melatonin that may help to improve response of the tumor to radiotherapy. In this review, the effects of melatonin on the modulation of immune responses in both normal and tumor tissues will be discussed.

Expression Levels of Two DNA Repair-related Genes under 8 Gy Ionizing Radiation and 100 Mg/Kg Melatonin Delivery In Rat Peripheral Blood

BACKGROUND

After radiation therapy (RT), some health hazards including DNA damages may occur where melatonin can play a protective role due to free radical generation. On the other hand, serious accidental overexposures may occur during RT due to nuclear accidents which necessitate the need for study on exposure to high-dose radiations during treatments.

OBJECTIVE

The aim of this study was to study the expression level of two genes in non-homologous end joining (NHEJ) pathways named Xrcc4 and Xrcc6 (Ku70) in order to examine the effect of melatonin on repair of DNA double-strand breaks (BSBs) caused by 8Gy ionizing radiation.

METHODS

One hundred eight male Wistar rats were irradiated with a whole body gamma radiation dose of 8Gy with or without melatonin pretreatments. They were divided into six different groups of control, 100 mg/kg melatonin alone, 8Gy irradiation alone, vehicle alone, vehicle plus 8Gy irradiation and 100 mg/kg melatonin plus 8Gy irradiation. Peripheral blood samples were collected at 8, 24 and 48 h after irradiation. Ku70 and Xrcc4 gene expression were evaluated by real-time quantitative polymerase chain reaction (qPCR) technique and analyzed by one-way ANOVA test.

RESULTS

Expression of Ku70 and Xrcc4 genes normalized against Hprt gene showed significant difference in melatonin plus irradiation group at 8h compared to the control group (p<0.05). At 24h post irradiation, gene expression changes were significantly upregulated in irradiation-alone group as well as melatonin plus irradiation group (p<0.05). No significant change was found in any groups compared to control group at 48 h time point.

CONCLUSION

We concluded that, by increasing expression level of Ku70 and Xrcc4 genes, 100 mg/kg melatonin administration 8 and 24 h before 8 Gyionizing radiation can significantly affect the repair of DNA DSBs in NHEJ pathway.

Association of interleukin-16 polymorphisms with disease progression and susceptibility in endometriosis

Interleukin-16 (IL-16) is a multifunctional pro-inflammatory cytokine that was previously found in association with complex disorders, and it is now cleared that this cytokine plays a critical role in regulation of cellular functions such as homoeostasis. Due to the complexity of endometriosis and its resemblance to cancer, we designed present case-control study to determine the effects of genetic polymorphisms of the human IL-16 gene on Iranian women's susceptibility to endometriosis. A total of 126 patients with endometriosis (stages I-IV) and 144 healthy women as control group were recruited to the study. We genotyped four single nucleotide polymorphisms of IL-16 gene (rs11556218 T>G, rs4778889 T>C, rs4072111 C>T and rs1131445 C>T). Genotyping was performed using PCR and restriction fragment length polymorphism. Our results showed that genotype distribution in two exonic polymorphisms including rs11556218 and rs4072111 was significantly different between Endometriosis patients and healthy individuals (P < 0.05). We have also found an association between rs4072111 and rs1131445 with progression to the severe stages (III-IV) of endometriosis (P < 0.05). Finally, we may conclude that IL-16 gene polymorphisms are highly associated with increased risk of endometriosis and could be considered as a susceptibility factor for endometriosis.

Experimental strategies towards increasing intracellular mitochondrial activity in oocytes: A systematic review

PURPOSE

The mitochondrial complement is critical in sustaining the earliest stages of life. To improve the Assisted Reproductive Technology (ART), current methods of interest were evaluated for increasing the activity and copy number of mitochondria in the oocyte cell.

METHODS

This covered the researches from 1966 to September 2015.

RESULTS

The results provided ten methods that can be studied individually or simultaneously.

CONCLUSION

Though the use of these techniques generated great concern about heteroplasmy observation in humans, it seems that with study on these suggested methods there is real hope for effective treatments of old oocyte or oocytes containing mitochondrial problems in the near future.

Expressional and Bioinformatic Analysis of Bovine Filia/Ecat1/Khdc3l Gene: A Comparison with Ovine Species

Maternal effect genes have highly impressive effects on pre-implantation development. Filia/Ecat1/Khdc3l is a maternal effect gene found in mouse oocytes and embryos, loss of which causes a 50% decrease in fertility. In the present study, we investigated Filia mRNA expression in bovine oviduct, 30- to 40-day fetus, liver, heart, lung, and oocytes (as a positive control), by RT-PCR and detected it only in oocytes. A 443 bp fragment was amplified only in oocytes and was sequenced as a part of bovine predicted Filia mRNA. We analyzed bovine and ovine Filia N-terminal peptide sequence in PHYRE2, and a KH domain was predicted. Protein alignment using ClustalW indicated a highly identical N-terminal extention between the 2 species. Immunohistochemical analysis using anti-bovine Filia antibody showed the expression of Filia protein in the zone surrounding the nuclear membrane, and in the subcortex of ovine oocytes of primary and antral follicles. However, in the bovine, Filia has been found through the oocyte cytoplasm of antral follicles, and here it is further confirmed in the primary follicles. Our data suggests a difference in Filia expression pattern between cow and sheep, although the sequence is highly conserved.

The Principal Forces of Oocyte Polarity Are Evolutionary Conserved but May Not Affect the Contribution of the First Two Blastomeres to the Blastocyst Development in Mammals

Oocyte polarity and embryonic patterning are well-established features of development in lower species. Whether a similar form of pre-patterning exists in mammals is currently under hot debate in mice. This study investigated this issue for the first time in ovine as a large mammal model. Microsurgical trisection of unfertilized MII-oocytes revealed that cortical cytoplasm around spindle (S) contained significant amounts of total maternal mRNAs and proteins compared to matched cytoplast hemispheres that were located either near (NS) or far (FS) -to-spindle. RT-qPCR provided striking examples of maternal mRNA localized to subcellular substructures S (NPM2, GMNN, H19, PCAF, DNMT3A, DNMT1, and STELLA), NS (SOX2, NANOG, POU5F1, and TET1), and FS (GCN) of MII oocyte. Immunoblotting revealed that specific maternal proteins DNMT3A and NANOG were asymmetrically enriched in MII-spindle-half of the oocytes. Topological analysis of sperm entry point (SEP) revealed that sperm preferentially entered via the MII-spindle-half of the oocytes. Even though, the topological position of first cleavage plane with regard to SEP was quite stochastic. Spatial comparison of lipid content revealed symmetrical distribution of lipids between 2-cell blastomeres. Lineage tracing using Dil, a fluorescent dye, revealed that while the progeny of leading blastomere of 2-cell embryos contributed to more cells in the developed blastocysts compared to lagging counterpart, the contributions of leading and lagging blastomeres to the embryonic-abembryonic parts of the developed blastocysts were almost unbiased. And finally, separated sister blastomeres of 2-cell embryos had an overall similar probability to arrest at any stage before the blastocyst (2-cell, 4-cell, 8-cell, and morula) or to achieve the blastocyst stage. It was concluded that the localization of maternal mRNAs and proteins at the spindle are evolutionarily conserved between mammals unfertilized ovine oocyte could be considered polar with respect to the spatial regionalization of maternal transcripts and proteins. Even though, the principal forces of this definitive oocyte polarity may not persist during embryonic cleavages.

Development of sheep primordial follicles encapsulated in alginate or in ovarian tissue in fresh and vitrified samples

In vitro follicle growth is a promising strategy for female fertility preservation. This study was conducted to compare the development of ovine follicles either isolated or in the context of ovarian cortical pieces after short term (8 days) three-dimensional culture in fresh and vitrified samples. Four different experiments were conducted; I) culture of ovarian cortical pieces encapsulated in 0.5% and 1% alginate and without alginate encapsulation (CP-0.5%, CP-1% and CP, respectively), II) culture of isolated primordial and primary follicles encapsulated in 1% and 2% alginate (IF-1% and IF-2%, respectively), III) culture of fresh and vitrified-warmed cortical pieces (F-CP and Vit-CP, respectively), and IV) culture of fresh and vitrified-warmed encapsulated isolated follicles (F-IF and Vit-IF, respectively). The number of secondary follicles after culture was negatively influenced by encapsulation of ovarian cortical pieces (6.3 ± 3.3 and 10.6 ± 0.9 vs 21.5 ± 2.3 in CP-0.5% and CP-1% vs CP, respectively). The diameter of follicles in IF-2% was higher than IF-1% (54.06 ± 2 vs 41.9 ± 1.5) and no significant difference in follicular viability was observed between the two groups. The proportions of different follicular types and their viability after culture in vitrified-warmed cortical pieces were comparable with fresh ones. The viability of vitrified-warmed isolated follicles was lower than fresh counterparts. The growth rate of fresh follicles was higher than vitrified-warmed follicles after culture (47.9 ± 1 vs 44.6 ± 1). In conclusion, while encapsulation of ovarian cortical pieces decreased the follicles' development, it could better support the growth of isolated follicles. Moreover, the viability and growth rate of isolated-encapsulated follicles was decreased by vitrification.

The Effect of Angiotensin on the Quality of In Vitro Produced (IVP) Sheep Embryos and Expression of Na(+)/K(+)/ATPase

BACKGROUND

The presence of rennin-angiotensin components in mammalian ovaries and their involvement in ovarian physiology have been established. In the present study, effects of angiotensin II (Ang II) on sodium-potassium adenosine triphosphatase (Na(+)/K(+)/ATPase) expression and development of sheep embryos was evaluated.

METHODS

The abattoir-derived Cumulus Oocyte Complexes (COC) were randomly allocated into three experimental groups; group I) in vitro Maturation (IVM) of oocytes in the presence of Ang II followed by in vitro fertilization (IVF)/in vitro Culture (IVC) (IVM group), group II) IVM/IVF of oocytes followed by IVC wherein the embryos were exposed to Ang II on day 4 of IVC (D4 group), and group III) IVM/IVF and IVC of oocytes without any angiotensin (Control). The blastocyst and hatching rates were recorded on days 6 to 8. Day 8 embryos were immunostained with primary and secondary antibodies against Na(+)/K(+)/ATPase α1 and β1 subunits.

RESULTS

Addition of Ang II during IVM and IVC significantly increased the hatching rate of blastocysts on day 8 compared to the control. The trophectoderm and total blastocyst cells' numbers were significantly increased by addition of Ang II to the IVM and IVC media, though the expression of Na(+)/K(+)/ATPase α1 and β1 subunits were positively influenced by the addition of Ang II on day 4 (D4 group).

CONCLUSION

In conclusion, it seems Ang II through positive effects on embryos, expressed as the greater hatching rate and blastocyst cell number, could increase the sheep embryo developmental rate. These improvements might be partly related to the greater expression of Na(+)/K(+)/ATPase α1 and β1 subunits when Ang II was added during IVC.

The Effect of Media Supplementation with Angiotensin on Developmental Competence of Ovine Embryos Derived from Vitrified-warmed Oocytes

BACKGROUND

This study was aimed to assess the effects of angiotensin II (Ang II) supplementation to the In Vitro Maturation (IVM) and In Vitro Culture (IVC) media of vitrified-warmed ovine oocytes on their developmental competence and expression of Na(+)/K(+)/ATPase in resulting embryos.

METHODS

The slaughterhouse-derived immature oocytes (n=1069) were randomly distributed into four experimental groups: groups I and II) IVM/IVF and IVC of fresh and vitrified oocytes without angiotensin supplementation (Control-Fresh and Control-Vit groups, respectively); group III) IVM of vitrified oocytes in the presence of Ang II followed by IVF/IVC (Vit-IVM group); and group IV) IVM/IVF of vitrified oocytes followed by IVC wherein the embryos were exposed to Ang II on day 4 of IVC (Vit-D4 group). The embryos were immunostained with primary antibodies against Na(+)/K(+)/ATPase α1 and β1 subunits.

RESULTS

In Vit-IVM and Vit-D4 groups, the rates of expanded and total blastocysts on day 7 as well as the proportion of blastocysts on day 8 were increased. The expression of Na(+)/K(+)/ATPase α1 and β1 subunits were positively influenced by the addition of Ang II on day 4 (Vit-D4 group).

CONCLUSION

The addition of Ang II to the IVM and IVC media could improve blastocysts formation in vitrified sheep oocytes. This improvement might be related to the greater expression of Na(+)/K(+)/ATPase α1 and β1 subunits when Ang II was added during IVC.

Expression of bovine Ecat1 gene in immature and in vitro matured oocytes as well as during early embryonic development

Ecat1 is a maternal effect gene that is exclusively expressed in oocytes and embryonic stem cells, and has an important role in pre-implantation development. This study was designed to investigate the expression of bovine Ecat1 gene in immature and in vitro matured oocytes as well as during early embryonic development, and also Ecat1 protein localization. Samples were obtained from slaughtered animals. RNA extractions were carried out from ovary, immature and in vitro matured oocytes and also different stages of embryonic development (2-, 4-, 8- to 16-cell stages and blastocysts). RT-PCR analysis revealed the expression of Ecat1 in ovary, oocytes and embryos. Analysis in FGENESH online tool predicted three exons and one transcription start site (TSS) in Ecat1 gene, and the 3' RACE-PCR result showed that just one splice variant was amplified. By quantitative real-time PCR technique, we showed that Ecat1 transcript increased at 8- to 16-cell-stage embryos and decreased in blastocyst stage (p < 0.05). Immunofluorescence analysis showed cytoplasmic localization of Ecat1 protein in bovine oocytes. Results demonstrated bovine Ecat1 expression at protein level and also indicated that Ecat1 has a significant higher embryonic expression at 8- to 16-cell stage. This embryonic expression is probably required for further developmental stages.

Enrichment of undifferentiated type a spermatogonia from goat testis using discontinuous percoll density gradient and differential plating

BACKGROUND

The well documented source for adult multipotent stem cells is Spermatogonial Stem Cells (SSCs). They are the foundation of spermatogenesis in the testis throughout adult life by balancing self-renewal and differentiation. The aim of this study was to assess the effect of percoll density gradient and differential plating on enrichment of undifferentiated type A spermatogonia in dissociated cellular suspension of goat testes. Additionally, we evaluated the separated fractions of the gradients in percoll and samples in differential plating at different times for cell number, viability and purification rate of goat SSCs in culture.

METHODS

Testicular cells were successfully isolated from one month old goat testis using two-step enzymatic digestion and followed by two purification protocols, differential plating with different times of culture (3, 4, 5, and 6 hr) and discontinuous percoll density with different gradients (20, 28, 30, and 32%). The difference of percentage of undifferentiated SSCs (PGP9.5 positive) in each method was compared using ANOVA and comparison between the highest percentage of corresponding value between two methods was carried out by t-test using Sigma Stat (ver. 3.5).

RESULTS

The highest PGP9.5 (94.6±0.4) and the lowest c-Kit positive (25.1±0.7) in Percoll method was significantly (p ≤ 0.001) achieved in 32% percoll gradient. While the corresponding rates in differential plating method for the highest PGP9.5 positive cells (81.3±1.1) and lowest c-Kit (17.1±1.4) was achieved after 5 hr culturing (p < 0.001). The enrichment of undifferentiated type A spermatogonia using Percoll was more efficient than differential plating method (p < 0.001).

CONCLUSION

Percoll density gradient and differential plating were efficient and fast methods for enrichment of type A spermatogonial stem cells from goat testes.

Male Pronuclear Formation using Dog Sperm Derived from Ectopic Testicular Xenografts, Testis, and Epididymis

BACKGROUND

Testis tissue xenografting and the resultant sperm in a xenograft may provide a unique approach to rescue the genetic material of males that die prematurely and is a model for the study of human spermatogenesis and can represent an alternative approach for fertility preservation in cancer patients. This study was aimed to evaluate the xenogenic dog sperm in formation of male pronucleus following injection into the sheep oocytes.

METHODS

The in vitro matured slaughterhouse derived sheep oocytes were subjected to Intracytoplasmic Sperm Injection (ICSI) with epididymal, testicular, and xenogenic dog sperm. The ICSI was performed after scoring of the sperm midpiece using an IX71-Olympus inverted microscope with Nomarsky optics. Within 1 hr after injection, the injected oocytes in activated group were exposed to 5 µM ionomycin for 5 min. The data were analyzed by Chi-square and ANOVA using SigmaStat, version 3.5, and p<0.05 was considered significant.

RESULTS

The formation of female pronucleus after ICSI of xenogenic sperm was higher than epididymal and testicular sperm in non-activated oocytes. The corresponding rate in activated oocytes was higher or comparable with testicular and epididymal sperm. The rate of male pronucleus formation after ICSI of xenogenic sperm was comparable with injection of two other sperm sources. Oocyte activation had an inductive role in female and male pronuclear formation.

CONCLUSION

Dog xenogenic sperm was capable to induce oocyte activation and proportion of male pronucleous formation was comparable to the testicular and epididymal sperm.

Comparison of proliferative and multilineage differentiation potential of sheep mesenchymal stem cells derived from bone marrow, liver, and adipose tissue

BACKGROUND

Despite major progress in our general knowledge related to the application of adult stem cells, finding alternative sources for bone marrow Mesenchymal Stem Cells (MSCs) has remained to be challenged. In this study successful isolation, multilineage differentiation, and proliferation potentials of sheep MSCs derived from bone marrow, adipose tissue, and liver were widely investigated.

METHODS

The primary cell cultures were prepared form tissue samples obtained from sheep 30-35 day fetus. Passage-3 cells were plated either at varying cell densities or different serum concentrations for a week. The Population Doubling Time (PDT), growth curves, and Colony Forming Unit (CFU) of MSCs was determined. The stemness and trilineage differentiation potential of MSCs were analyzed by using molecullar and cytochemical staining approaches. The data was analyzed through one way ANOVA using SigmaStat (ver. 2).

RESULTS

The highest PDT and lowest CFU were observed in adipose tissue group compared with other groups (p<0.001). Comparing different serum concentrations (5, 10, 15, and 20%), irrespective of cell sources, the highest proliferation rate was achieved in the presence of 20% serum (p<0.001). Additionally, there was an inverse relation between cell seeding density at culture initiation and proliferation rate, except for L-MSC at 300 cell seeding density.

CONCLUSION

All three sources of fetal sheep MSCs had the identical trilineage differentiation potential. The proliferative capacity of liver and bone marrow derived MSCs were similar at different cell seeding densities except for the higher fold increase in B-MSCs at 2700 cells/cm (2) density. Moreover, the adipose tissue derived MSCs had the lowest proliferative indices.

Culture of Ovine IVM/IVF Zygotes in Isolated Mouse Oviduct: Effect of Basal Medium

BACKGROUND

The basal medium that supports Isolated Mouse Oviduct (IMO) is important for supporting embryo development and quality.

METHODS

The culture of ovine IVM/IVF zygotes was done in IMO using SOFaaciBSA and SOFaaBSA as basal medium of IMO and in SOFaaBSA alone as control. For preparation of IMO mature inbred strain C57BL/6 female mice were synchronized and mated with vasectomized males. The females with vaginal plug were sacrificed and the zygotes were transferred in to the isolated oviduct at 20 hpi. The oviducts were cultured with SOFaaciBSA and SOFaaBSA for 6 days. Another group of zygotes were cultured in SOFaaBSA alone as control.

RESULTS

Culture of zygotes in the IMO with SOFaaciBSA and SOFaaBSA, did not significantly affect the development and quality of embryos (p > 0.05). The hatching rate, total and trophectoderm cells number in IMO groups' blastocysts were significantly higher than SOFaaBSA alone. The morphological appearance of IMO blastocysts was superior to SOFaaBSA alone. When the quality of oocytes was poor, IMO could better support ovine embryo development either with SOFaaBSA or SOFaaciBSA than SOFaaBSA alone and there was a significant difference in blastocyst formation at day 6 with SOFaaBSA alone.

CONCLUSION

The culture of ovine IVM/IVF zygotes in IMO using two highly efficient ruminant embryo culture media not only could support development of ovine embryos similar to the level in non IMO culture system (SOFaaBSA alone) but also could improve the quality of resulting embryos. Additionally, IMO could better support the development of ovine embryos derived from poor quality oocytes compared to the SOFaaBSA alone.

The In vitro Fertilization of Ovine Oocytes in the Presence of Oviductal Cells and its Effect on the Expression of Zygote Arrest 1 (Zar1) and Subsequent Embryonic Development

BACKGROUND

The cells of mammalian female reproductive tract have been widely used for in vitro fertilization (IVF). This study was designed to study the effects of oviductal epithelial cells (OECs) and their conditioned medium during IVF on subsequent embryonic development and the relative abundance of zygote arrest 1 (Zar1) transcript in ovine zygotes.

METHODS

The in vitro matured ovine oocytes were randomly fertilized in the following culture conditions: I) SOFaaBSA+20% sheep serum (control), II) SOFaa BSA+20% sheep serum (50 µl) in the presence of OECs, III) SOFaaBSA+20% sheep serum (100 µl) in the presence of OECs, and IV) OECs conditioned medium (CM). Sigma Stat (Version 2.0) software and one-way ANOVA were considered for statistical analysis. A p<0.05 was considered statistically significant.

RESULTS

The cleavage, blastocyst, and hatched blastocyst rates in OECs and CM groups were significantly lower than the control group (p<0.01). In co-cultured groups, the application of two different volumes of IVF medium showed no difference in embryonic developmental indices. The Zar1 gene expression in zygotes produced in the presence of OECs was significantly higher than those produced in the control and CM groups (p<0.05).

CONCLUSION

Neither the presence of oviductal epithelial cells nor their conditioned medium could improve the developmental potential of ovine embryos during IVF. Moreover, no relationship was observed between the relative abundance of Zar1 transcript in zygotes produced in different conditions and the corresponding subsequent embryonic development.

Isolation, identification, and culture of goat spermatogonial stem cells using c-kit and PGP9.5 markers

INTRODUCTION

Presently the techniques for making transgenic animals are cumbersome, required costly instruments and trained man-power. The ability of spermatogonial stem cells (SSCs) to integrate foreign genes has provided the opportunity for developing alternate methods for generation of transgenic animals. One of the big challenges in this field is development of the methods to identify and purify donor SSCs by antibody mediated cell sorting.

PURPOSE

The present study was aimed to identify goat subpopulations of SSCs using polyclonal antibodies against PGP9.5 and c-kit molecular markers as well as the growth characteristics of SSCs during short term culture.

METHODS

One month old goats' testicular samples were subjected for immunohistochemical and immunocytochemical evaluations. The enzymatically isolated SSCs were cultured in DMEM plus FCS supplemented with (treatment) or without (control) growth factors (GDNF, LIF, FGF, and EGF) for 2 weeks. At the end of culture the morphological characteristics of SSCs colonies and immunocytochemical staining were evaluated.

RESULTS

The number and size of colonies in treatment groups were significantly (P < 0.01) higher than corresponding values in controls. The presence of PGP 9.5 and c-kit antigens was confirmed in immunocytochemical evaluation. In immunocytochemical evaluation, the proportion of c-kit and PGP9.5 positive cells were significantly (P < 0.001) higher in control and treatment groups, respectively.

CONCLUSIONS

The presence of PGP9.5 and c-kit antigens was confirmed in goat SSCs. Moreover, culture medium supplementation with growth factors could effectively retain the undifferentiation status of SSCs, reflected as a higher population of PGP9.5 positive cells, after short term culture.

The Effect of Macromolecule Source and Type of Media During in vitro Maturation of Sheep Oocytes on Subsequent Embryo Development

BACKGROUND

Oocyte maturation and subsequent in vitro production (IVP) of embryos are affected by diverse groups of chemicals in maturation medium which are needed for successful mammalian oocyte maturation during which the dramatic cytoplasmic and nuclear reprogramming events take place. This study was designed to evaluate the effects of protein source (fetal bovine serum, FBS, and bovine serum albumin, BSA) as well as two different maturation media during in vitro maturation of ovine oocytes on subsequent embryo development.

METHODS

Cumulus oocyte complexes were recovered from ovaries obtained from slaughter house and cultured for 24 hr in either TCM-199 or SOFaa maturation medium supplemented with 10% (v/v) FBS or 0.8% (w/v) BSA. Data were analyzed by one-way ANOVA using Sigma Stat (Ver. 2). A p-value smaller than 0.05 was considered statistically significant.

RESULTS

The proportions of cleavage and total blastocyst (evaluated on days 3 and 6, respectively) were significantly higher in FBS than BSA supplemented groups, though no differences were observed between the two used different maturation media. The cryotolerance of blastocysts was negatively influenced by the presence of FBS rather than BSA during IVM. The quality of produced embryos, however, was affected neither by the source of macromolecules nor the maturation medium in terms of hatching rate, total blastocyst cells and inner cell mass/total cell ratio.

CONCLUSION

The rate of oocyte development was improved by the presence of FBS, though the cryosurvival of resulting blastocysts was negatively influenced by the presence of the serum during in vitro production of sheep oocytes.

Isolation, culture and identification of epidermal stem cells from newborn mouse skin

In healthy individuals, skin integrity is maintained by epidermal stem cells which self-renew and generate daughter cells that undergo terminal differentiation. Epidermal stem cells represent a promising source of stem cells, and their culture has great potential in scientific research and clinical application. However, no single method has been universally adopted for identifying and isolating epidermal stem cells. Here, we reported the isolation and characterization of putative epidermal stem cells from newborn mouse skin. The keratinocytes were separated enzymatically. Putative epidermal stem cells were selected by rapid adherence on a composite matrix made of type I collagen and fibronectin. Unattached cells were discarded after 10 min, and the attached cells were cultured in a defined culture medium. The isolated cells showed the typical epidermal stem cell morphology. Immunofluorescence indicated that the cells were strongly stained for β1 integrin family of extracellular matrix receptors. In conclusion, mouse putative epidermal stem cells were successfully isolated from newborn mouse epidermis on the basis of high rapid adhesion to extracellular matrix proteins and cultured in vitro.