Omega 6/Omega 3 Ratio Is High in Individuals with Increased Sperm DNA fragmentation

An imbalance between omega-6 and omega-3 fatty acids in sperm has been linked with lipid peroxidation and DNA damage in sperm, indicating a possible correlation to fertility potential. This cross-sectional study involved 56 infertile men (aged 25-45), and assessed the relationship between the omega-6 to omega-3 fatty acid ratio in sperm and seminal plasma with sperm DNA fragmentation. Individuals were categorized based on high or low levels of sperm DNA fragmentation according to two tests (TUNEL and SCSA assay less or greater than 10 and 30%, respectively), and their fatty acid composition, as well as sperm functional tests, were analyzed. Results showed that men with high DNA fragmentation exhibited higher percentages of total saturated, monounsaturated, and omega-6 to omega-3 fatty acid ratios in both sperm (P < 0.001) and seminal plasma (P < 0.001) compared to men with low DNA fragmentation. The percentage of sperm lipid peroxidation, and residual histone (P < 0.05) were higher, while the percentage of sperm motility (P < 0.001) was lower in the former compared to the latter group. Moreover, Pearson's correlation revealed positive associations between the omega-6 to omega-3 fatty acid ratio with sperm lipid peroxidation, DNA fragmentation, and residual histones in both sperm and seminal plasma. Overall, these observations suggest that consumption of omega-3 fatty acids may be related to male fertility potential, as it appears that individuals with a high percentage of omega-3 fatty acids have better sperm quality compared to men with a lower omega-3 fatty acid.

Evaluation of the p53 pathway in polycystic ovarian syndrome pathogenesis and apoptosis enhancement in human granulosa cells through transcriptome data analysis

The polycystic ovarian syndrome (PCOS) is closely associated with enhanced apoptosis of granulosa cells, which have a vital role in maturation of oocytes. p53 plays a critical role in the regulation of apoptosis and cell cycle arrest, metabolism and insulin resistance. The aim of this study was to investigate the impact of p53 pathway in enhancing apoptosis and abnormal function of granulosa cells. In this study, microarray analysis and RNA sequencing were downloaded from the GEO and used as datasets. Principal Component Analysis (PCA) and online SSizer tool were applied to evaluate the experiment quality control and sample sufficiency, respectively. Bioinformatics' analyses were performed on the selected datasets, and validated by qRT-PCR and western blot analyses. Three datasets out of five ones were chosen for re-analyzing based on the PCA outcomes. 21 deregulated genes were identified via filters including p < 0.05 and |log2FC|≥ 1. Functional enrichment analysis confirmed the relevance of cell cycle regulation and apoptosis as common biological hallmarks in PCOS. Results have shown differentially expressed p53 target genes involved in apoptosis (BAX, FAS, PMAIP1, and CASP8), cell cycle (Cyclins, Cyclin dependent kinases), glucose metabolism and insulin resistance (THBS1), and p53 regulation (MDM2). Subsequently, the relative mRNA expression of FAS, PMAIP1 and MDM2 genes, and protein levels of p53 and MDM2 were confirmed using granulosa cells collected from 20 PCOS women and 18 control individuals by qRT-PCR and western blot, respectively. Results of this study represent the possible role of p53 pathway in pathogenesis of PCOS particularly, through the enhancement of apoptosis in granulosa cells.

Transcriptomic screening to identify hub genes and drug signatures for PCOS based on RNA-Seq data in granulosa cells

BACKGROUND

Polycystic ovary syndrome (PCOS) is one of the most incident reproductive diseases, and remains the main cause of female infertility. Granulosa cells play a critical role in normal follicle development and steroid hormones synthesis. In spite of extensive research, no sole medication has been approved by FDA to treat PCOS. This study aimed to investigate the novel therapeutics targets in PCOS, focusing on granulosa cells transcriptome functional analysis with a drug repositioning approach.

METHODS

PCOS microarray and RNA-Seq datasets in granulosa cells were screened and reanalyzed. KEGG pathway enrichment and interaction network analyses were performed and followed by a set of drug signature screening and Poly-pharmacology survey.

RESULTS

545 deregulated genes were identified via filters including p_adj < 0.05 and |log2FC| > 1. Amongst the top 15 KEGG pathways significantly enriched, metabolism of xenobiotics by cytochrome P450, steroid hormone biosynthesis and ovarian steroidogenesis were observed. The Protein-Protein Interaction network identified 18 hub genes amongst this set. Interestingly, most candidate drug signatures have been introduced by databases are either FDA approved or entered into clinical trials, including melatonin, resveratrol and raloxifene. Investigational or experimental introduced drugs obey rules of drug-likeness with almost safe and acceptable ADMET properties. Notably, 21 top target genes of the final drug set were also included in the granulosa significant differentially expressed genes.

CONCLUSION

Results of the current study represent approved, investigational and experimental drug signatures according to the differentially expressed genes in granulosa cells with supported literature reviews. This data might be useful for researchers and clinicians to pave the way for better management of PCOS.

The Protective Effects of Alpha Lipoic Acid on Human Sperm Function During Freezing-Thawing

BACKGROUND

Sperm cryopreservation is presently used for conservation of male gametes in assisted reproduction technologies (ART). Despite the benefits of sperm banking, freeze-thawing process is injurious to sperm integrity due to induced oxidative stress by cold stress. Oxidative stress reduces sperm motility, viability and DNA integrity.

OBJECTIVE

To investigate the effect of alpha lipoic acid (ALA) on human sperm function during the freeze-thawing process.

MATERIALS AND METHODS

Thirty semen samples were collected and different concentrations (0, 0.05, 0.1, 0.2, 0.4, 0.8, and 8mM) of ALA were added to a sperm freeze medium and its effects on sperm motility, DNA damage, and lipid peroxidation of frozen-thawed spermatozoa were assessed.

RESULTS

The addition of 0.2 mM ALA to the sperm freeze medium resulted in significant improvement in percentage of sperm motility, less DNA damage and decreased lipid peroxidation during freeze-thawing process (p<0.05).

CONCLUSION

ALA improves the cryo-protective capacity of sperm freeze medium used for human semen by protecting the sperm from ROS attack induced by the freezing-thawing process. We suggest that sperm freeze medium supplemented with 0.2 mM ALA would be beneficial for the cryopreservation of male gametes in ART.

Could high DNA stainability (HDS) be a valuable indicator of sperm nuclear integrity?

Background

The Sperm Chromatin Structure Assay (SCSA®), in addition to identifying the DNA Fragmentation Index (DFI) also identifies High DNA satiability (HDS), supposed to reflect the nuclear compaction of spermatozoa. However, data on what exactly this parameter reveals, its relevance and usefulness are contradictory. In order to shed light on this situation, spermatozoa of a cohort (N = 397) of infertile men were subjected to the SCSA®, TUNEL (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling) and CMA3 (Chromomycin A3) tests. In a smaller subcohort (N = 100), aniline blue (AB) and toluidine blue (TB) staining were performed in addition. The objective of this study was thus to answer the question of whether HDS is a relevant and reliable parameter to be taken into account?

Results

HDS does not appear to be a reliable indicator of nuclear immaturity because it shows a weak correlation with the CMA3, AB and TB stains. The low correlation of HDS with sperm DNA fragmentation (TUNEL and SCSA®) and DNA condensation (CMA3, AB and TB) tests suggests that these two parameters could be decoupled. Unlike DFI and TUNEL, HDS has not been shown to correlate with classic clinical situations of male infertility (asthenozoospermia, teratozoospermia or astheno-teratozoospermia).

Conclusion

HDS correlates poorly with most tests that focus specifically on the level of maturity of the sperm nucleus. To our knowledge, this study is the first to compare SCSA®, TUNEL, AB, TB and CMA3 assays on identical samples. It shows the potency, consistency and limitations of each test and the care that must be taken in their interpretation.

siRNA inhibition and not chemical inhibition of Suv39h1/2 enhances pre-implantation embryonic development of bovine somatic cell nuclear transfer embryos

The efficiency of somatic cell nuclear transfer (SCNT) is low due to the strong resistance of somatic donor cells to epigenetic reprogramming. Many epigenetic drugs targeting DNA methylation and histone acetylation have been used in attempts to improve the in vitro and in vivo development of SCNT embryos. H3K9me3 has been shown to be an important reprogramming barrier for generating induced pluripotent stem cells (iPSCs) and SCNT embryos in mice and humans. In this study, we examined the effects of selective siRNA and chemical inhibition of H3K9me3 in somatic donor cells on the in vitro development of bovine SCNT embryos. Chaetocin, an inhibitor of SUV39H1/H2, was supplemented during the culture of donor cells. In addition, the siRNA knockdown of SUV39H1/H2 was performed in the donor cells. The effects of chaetocin and siSUV39H1/H2 on H3K9me3 and H3K9ac were quantified using flow cytometry. Furthermore, we assessed chaetocin treatment and SUV39H1/H2 knockdown on the blastocyst formation rate. Both chaetocin and siSUV39H1/H2 significantly reduced and elevated the relative intensity level of H3K9me3 and H3K9ac in treated fibroblast cells, respectively. siSUV39H1/H2 transfection, but not chaetocin treatment, improved the in vitro development of SCNT embryos. Moreover, siSUV39H1/H2 altered the expression profile of the selected genes in the derived blastocysts, similar to those derived from in vitro fertilization (IVF). In conclusion, our results demonstrated H3K9me3 as an epigenetic barrier in the reprogramming process mediated by SCNT in bovine species, a finding which supports the role of H3K9me3 as a reprogramming barrier in mammalian species. Our findings provide a promising approach for improving the efficiency of mammalian cloning for agricultural and biomedical purposes.

Mesoporous bioactive glasses for the combined application of osteosarcoma treatment and bone regeneration

In this study, mesoporous bioactive glass (MBG) sub-micro particles were prepared through sol-gel synthesis and possessed a uniform and spherical structure with particle size of 302 ± 43 nm, a pore size of 4 nm and a high surface area of 354 m² g^-1. Alendronate (AL) is often used for the treatment of bone associated diseases, in particular osteosarcoma. However, due to the low bioavailability and high toxicity at increased doses, local and sustained release would be an ideal approach to AL delivery. Here, MBGs and aminated MBGs (AMBG) were applied as carriers for AL loading. High encapsulation efficiency of 75% and 85% and loading efficiency of 60% and 63%, for MBG and AMBG, respectively, was achieved. The release profile of AL from AMBG showed a better sustained and controlled release mechanism compared to MBG. In vitro results demonstrated the non-cytotoxic nature of both MBG and AMBG following exposure to MG63 osteoblast like cell line. AL release from MBG and AMBG, even at lower concentration, provoked decreased MG63 proliferation. The osteogenic potential of MBG and AMBG following exposure to dental pulp stem cells was evaluated using alizarin red assay.

Cathepsin B inhibitor improves developmental competency and cryo-tolerance of in vitro ovine embryos

Background

Cathepsin B is a lysosomal cysteine protease involved in apoptosis and oocytes which have lower developmental competence show higher expression of Cathepsin B. Furthermore, expression of Cathepsin B show a decreasing trend from oocyte toward blastocyst stage.

Results

Present study assessed the effect of cathepsin B inhibitor, E-64, on developmental competency and cryo-survival of pre-implantation ovine IVF derived embryos. Cathepsin B inhibitor was added during day 3 to 8 of development. One μM E-64 was defined as the optimal concentration required for improving blastocyst rate. This concentration also reduced DNA fragmentation and BAX as apoptotic markers while increasing total cell number per blastocyst and improving anti-apoptotic marker, the BCL2. We further showed that addition of 1.0 μM of E-64 during day 3 to 8 of development improved re-expansion and hatching rates of blastocysts post vitrification. E-64 also reduced rate of DNA fragmentation and BAX expression and increased total cell number per blastocyst and BCL2 expression post vitrification. However, addition of E-64 post vitrification reduced the hatching rate.

Conclusion

Therefore, it can be concluded that inhibition of cathepsin B in IVC, not only improves quality and quantity of blastocysts but also improves the cryo-survival of in vitro derived blastocysts.

Association between total globozoospermia and sperm chromatin defects

Globozoospermia is a severe sperm morphological anomaly leading to primary infertility and low fertilisation following intracytoplasmic sperm injection (ICSI). This phenotype is observed in less than 0.1% of infertile men and is determined by small, round-headed spermatozoa with absence of an acrosomal cap, acrosome protease and also cytoskeletal proteins. Failure of oocyte activation is considered as the main cause of fertilisation failure in these individuals post-ICSI. Therefore, artificial oocyte activation (AOA) along with ICSI is commonly implemented. However, based on previous report, fertilisation rate remains low despite implementation of ICSI-AOA. Therefore, other mechanisms like sperm chromatin packaging and DNA fragmentation may account for low fertilisation and development post-ICSI-AOA. Therefore, this study aims to assess and compare the degree of sperm protamine deficiency and DNA fragmentation in large population of infertile men with total globozoospermia (30 globozoospermic men presenting with 100% round-headed spermatozoa) with 22 fertile individuals using chromomycin A3 and TUNEL assay respectively. Results clearly show that mean of sperm concentration and percentage of sperm motility were significantly lower, while percentage of sperm abnormal morphology, protamine-deficient and DNA-fragmented spermatozoa were significantly higher in infertile men with globozoospermia compared to fertile men. Therefore, increased sperm DNA damage in globozoospermia is likely related to defective DNA compaction and antioxidant therapy before ICSI-AOA could be recommended as an appropriate option before ICSI-AOA.

Effects of Tempol and Quercetin on Human Sperm Function after Cryopreservation

　　BACKGROUND: Quercetin is a flavonoid with high reactive oxygen species (ROS) scavenging and ion chelating activity. It also enhances the activity of antioxidant enzymes and reduces enzymatic activity such as NADPH oxidase and NADH-dependent oxido-reductase. Tempol, as a superoxide dismutase mimetic agent, converts superoxide to less toxic hydrogen peroxide (H₂O₂), but cannot reduce highly toxic hydroxyl radicals in Fenton or Haber-Weiss reactions mediated with free iron or cupper.

OBJECTIVE

The study was to compare the effect of Quercetin and Tempol in an optimized commercial cryo-protective media on ROS induced cryoinjury for the first time.

MATERIALS AND METHODS

Following administration of these compounds during freezing process, sperm motility, viability, ROS production and DNA integrity were assessed before and after freezing/thawing process.

RESULTS

Data showed that 10 µM Quercetin and 5 µM Tempol significantly improved sperm motility and viability, but they together had no additive effect. Supplementation with Quercetin alone or combination of Quercetin with Tempol decrease the ROS concentration, but the reduction was not significant for Tempol alone compared to control group. Quercetin and Tempol significantly decrease DNA fragmentation.

CONCLUSION

The supplementation of Quercetin or Tempol, but not their combination improves the quality of cryopreserved human semen.

Association of vitamin D status with semen quality and reproductive hormones in Iranian subfertile men

Although vitamin D deficiency is one of the most common health problems throughout the world, including Iran, conflicting information exists on the potential association between serum vitamin D levels and semen quality. This study intended to evaluate the association between serum vitamin D [25(OH) D3] with semen quality and hormones in Iranian subfertile men. We also compared mean vitamin D and hormone levels in normospermic men with oligoasthenoteratozoospermia (OAT) men. This cross-sectional study was conducted on 278 men who were referred to Royan Infertility Clinic (Tehran, Iran) from March to September 2014. The participants were categorized into two groups; of 186 normospermic and 92 OAT patients according to World Health Organization 2010 criteria. Each participant provided informed consent prior to launching research. Participants completed two general questionnaires of nutritional status. Blood and semen samples were obtained for assessment, and all data were adjusted for age, body mass index (BMI), and season. Vitamin D levels were classified according to Institute of Medicine guidelines. Vitamin D deficiency, insufficiency, and normal levels were observed in 8.6%, 43.6%, 47.8% of participants, respectively. No association was found between daily dietary intake of vitamin D and calcium with sperm parameters. Serum vitamin D was inversely correlated with PTH (p < 0.045). In normospermic men, serum vitamin D levels categorized were not correlated with semen parameters and reproductive hormones (FSH, LH, testosterone(T), and FT), whereas sperm motility showed a positive correlation with vitamin D categorized in OAT men (rs = 0.131, p = 0.028). In conclusion, there was a high incidence of deficiency and insufficiency 25(OH) D Levels (<20ng/ml) observed in Iranian men (52.2%). Moreover, our findings showed a correlation between vitamin D levels and sperm motility in OAT men, which requires further studies.

Comparative dynamics of 5-methylcytosine reprogramming and TET family expression during preimplantation mammalian development in mouse and sheep

Despite previous assumption that paternal active DNA demethylation is an evolutionary conserved phenomenon in mammals, emerging studies in other species, particularly sheep, do not support this issue. Recently, ten eleven translocation (TET) enzymes have been suggested as intermediates in genome-wide DNA demethylation through the iterative conversion of five methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC)/5-formylcytosine/5-carboxylcytosine (5caC) derivatives. This study investigated whether TET enzymes and 5mC derivatives are also involved in dynamic reprogramming of early sheep embryos derived by fertilization. Mouse zygotes and developing embryos were considered as control. Obtained results reported substantial differences in dynamics of parent-of-origin-specific patterns of 5mC reprogramming and generation/dilution of 5mC derivatives (5hmC and 5caC) between mouse and sheep early zygotes. Sheep zygotes reported a gradual and insignificant decrease pattern of parental pronucleus 5mC, which was notably replication independent, coincided with gradual generation of 5hmC and 5caC. Although the expression profiles of TET family of enzymes (Tet1, Tet2, and Tet3), with the main exception being Tet2 at later developmental stages, were similar between mouse and sheep developing embryos. In addition, although the expression level of Tet3 was higher than Tet1 and Tet2 in MII oocytes and zygotes in both mouse and sheep, the expression of Tet3 in mouse was higher than sheep in both MII oocytes and zygotes. The contrasting dynamics of 5mC reprogramming between these two species may be associated with the particular evolutionary differences that exist between developmental program of rodents and ruminants, particularly during peri-implantation stages.

Systematic selection of small molecules to promote differentiation of embryonic stem cells and experimental validation for generating cardiomyocytes

Small molecules are being increasingly used for inducing the targeted differentiation of stem cells to different cell types. However, until now no systematic method for selecting suitable small molecules for this purpose has been presented. In this work, we propose an integrated and general bioinformatics- and cheminformatics-based approach for selecting small molecules which direct cellular differentiation in the desired way. The approach was successfully experimentally validated for differentiating stem cells into cardiomyocytes. All predicted compounds enhanced expression of cardiac progenitor (Gata4, Nkx2-5 and Mef2c) and mature cardiac markers (Actc1, myh6) significantly during and post-cardiac progenitor formation. The best-performing compound, Famotidine, increased the percentage of Myh6-positive cells from 33 to 56%, and enhanced the expression of Nkx2.5 and Tnnt2 cardiac progenitor and cardiac markers in protein level. The approach employed in the study is applicable to all other stem cell differentiation settings where gene expression data are available.

Pioglitazone significantly prevented decreased rate of neural differentiation of mouse embryonic stem cells which was reduced by Pex11β knock-down

Peroxisomes constitute special cellular organelles which display a variety of metabolic functions including fatty acid oxidation and free radical elimination. Abundance of these flexible organelles varies in response to different environmental stimuli. It has been demonstrated that PEX11β, a peroxisomal membrane elongation factor, is involved in the regulation of size, shape and number of peroxisomes. To investigate the role of PEX11β in neural differentiation of mouse embryonic stem cells (mESCs), we generated a stably transduced mESCs line that derives the expression of a short hairpin RNA against Pex11β gene following doxycycline (Dox) induction. Knock-down of Pex11β, during neural differentiation, significantly reduced the expression of neural progenitor cells and mature neuronal markers (p<0.05) indicating that decreased expression of PEX11β suppresses neuronal maturation. Additionally, mRNA levels of other peroxisome-related genes such as PMP70, Pex11α, Catalase, Pex19 and Pex5 were also significantly reduced by Pex11β knock-down (p<0.05). Interestingly, pretreatment of transduced mESCs with peroxisome proliferator-activated receptor γ agonist (pioglitazone (Pio)) ameliorated the inhibitory effects of Pex11β knock down on neural differentiation. Pio also significantly (p<0.05) increased the expression of neural progenitor and mature neuronal markers besides the expression of peroxisomal genes in transduced mESC. Results elucidated the importance of Pex11β expression in neural differentiation of mESCs, thereby highlighting the essential role of peroxisomes in mammalian neural differentiation. The observation that Pio recovered peroxisomal function and improved neural differentiation of Pex11β knocked-down mESCs, proposes a potential new pharmacological implication of Pio for neurogenesis in patients with peroxisomal defects.

Chemically assisted somatic cell nuclear transfer without micromanipulator in the goat: effects of demecolcine, cytochalasin-B, and MG-132 on the efficiency of a manual method of oocyte enucleation using a pulled Pasteur pipette

The present study aimed to facilitate widespread application of a previously described manual method of somatic cell nuclear transfer (SCNT) by investigating the effects of demecolcine (a microtubule-depolymerizing chemical), cytochalasin-B (a microfilament-depolymerizing chemical: 2.5μg/ml for 15min) and MG-132 (a proteasome inhibitor chemical) on the (i) incidence of cytoplasmic protrusion of MII chromosomes, (ii) improvement of manual oocyte enucleation, and (iii) in vitro and in vivo developmental competence of SCNT embryos in the goat. Following in vitro maturation, around 65% of goat oocytes contained a characteristic cytoplasmic protrusion of MII-chromosomes. Treatment with demecolcine (0.4μg/ml for 30min) significantly increased this rate to 92.2±4.5%. Treatment with MG-132 (2μM for 30min) could not improve this rate when used alone (61.4±11.5%), but when combined with demecolcine (86.4±8.1%). Treatment with cytochalasin-B completely suppressed this rate whenever used, either alone (7.7±5.1%) or in combination with demecolcine (3.9±1.3%). In a direct comparison, there was no significant difference in quantity and quality of embryos propagated by the manual vs. micromanipulation-based methods of SCNT (cleavage: 85.3±4.5 vs. 89.5±8.9%, blastocyst: 19.5±4.3 vs. 24.3±4.4%, grade 1 and 2 blastocyst: 33.8±7.1 vs. 29.5±6.3%, total cell count: 125±11.1 vs. 122±10.5, respectively). Furthermore, development to live kids at term was not significant between the two SCNT methods. From both technical and economical points of view, the overall in vitro and in vivo efficiency of this manual method of SCNT proved it a simple, fast and efficient alternative for large scale production of cloned goats.

A physiological, rather than a superovulated, post-implantation environment can attenuate the compromising effect of assisted reproductive techniques on gene expression in developing mice embryos

Assisted reproductive techniques (ARTs) may perturb the pre-/peri-conception microenvironments, which subsequently threaten the health of offspring. This study aimed to investigate the effects of superovulation, vitrification, in vitro culture, and embryo transfer on the expression of epigenetic modulators, imprinted genes, and pluripotency markers in expanded blastocysts and Day-9.5 (D9.5) concepti. Results revealed that 53.4% (8/15) and 86.7% (13/15) of genes in the fetus and placenta, respectively, have similar patterns of transcription in all D9.5 concepti, despite the perturbed mRNA expression observed at the blastocyst stage for each embryo-production technique. These observations indicate a counterbalancing of the abnormal expression pattern analyzed at the blastocyst stage during post-implantation development, particularly when the uterus of a naturally synchronized foster mother is employed. Superovulation resulted in the most abnormal expression patterns compared to other treatment groups, although these same blastocysts were able to develop in a synchronized uterus. Thus, superovulation creates a hormonal environment that negatively affected gene expression and impairs fetal growth more adversely during post-implantation development than other ART protocols, such as in vitro culture, vitrification, or embryo transfer-although each did contribute negatively to the implantation and development process. Together, these results may have implications for treating infertility in humans.

A Novel Method of Somatic Cell Nuclear Transfer with Minimum Equipment

Somatic cell nuclear transfer (SCNT) is an exceptional experimental biology technique with an arguably great contribution to our current understanding of developmental plasticity. Many students and young researchers are interested in taking advantage of SCNT virtues in their experiments but the cost of micromanipulation microscopes, intensive training programs, and also the sophisticated process of SCNT may dissuade them from entering this amazing field of science. Here, we describe the details of a streamlined manual method of SCNT that can be performed using very basic equipment found in every embryology laboratory: the Pasteur pipette and stereomicroscope. The overall method introduced is very simple and a person with no previous experience in cloning can learn and adopt the basic routines of this technique independently.

Glial cell line-derived neurotrophic factor in combination with insulin-like growth factor 1 and basic fibroblast growth factor promote in vitro culture of goat spermatogonial stem cells

Growth factors are increasingly considered as important regulators of spermatogonial stem cells (SSCs). This study investigated the effects of various growth factors (GDNF, IGF1, bFGF, EGF and GFRalpha-1) on purification and colonization of undifferentiated goat SSCs under in vitro and in vivo conditions. Irrespective of the culture condition used, the first signs of developing colonies were observed from day 4 of culture onwards. The number of colonies developed in GDNF + IGF1 + bFGF culture condition was significantly higher than the other groups (p < 0.05). In contrast, the size of colonies developed in GDNF + EGF + LIF culture condition was significantly higher than the other groups (p < 0.05). Immunocytochemical stationing for specific biomarkers of somatic cells (vimentin, alpha-inhibin and α-SMA) and spermatogonial cells (PLZF, THY 1, VASA, alpha-1 integrin, bet-1 integrin and DBA) revealed that both cell types existed in developing colonies, irrespective of the culture condition used. Even though, the relative abundance of VASA, FGFR3, OCT4, PLZF, BCL6B and THY1 transcription factors in GDNF + IGF1 + bFGF treatment group was significantly higher than the other groups (p < 0.05). Additionally, goat SSCs developed in the latter culture condition could colonize within the seminiferous tubules of the germ-cell depleted recipient mice following xenotransplantation. Obtained results demonstrated that combination of GDNF with IGF1 and bFGF promote in vitro culture of goat SSCs while precludes uncontrolled proliferation of somatic cells.

Optimization protocol for storage of goldfish (Carassius auratus) embryos in chilled state

A series of five experiments were conducted to explore suitable conditions for storing of goldfish embryos in a chilled state. The factors studied were embryo stage, storage temperature, physiological saline solutions and goldfish artificial coelomic fluid (GFACF) medium, antibiotics (penicillin and streptomycin), antioxidants (vitamin E, vitamin C), buffer (Hepes, Tris) and BSA (bovine serum albumin). First, goldfish embryos at eight developmental stages were incubated in aerated and dechlorinated tap water at 0 °C for 24 h. Result shows that early developmental stages were most sensitive to chilling. Heartbeat-stage goldfish embryos were chilled at 0, 4 or 8 °C for up to 72 h in water, and chilled storage was possible only for up to 18, 24 and 48 h at 0, 4 and 8 °C, respectively, without a decrease in viability. Chilling of goldfish embryos at 8 °C in GFACF medium and Dettlaff's solution instead of water and other physiological saline solutions prolonged their viability (p < 0.01). Nevertheless, viability of chilled embryos in GFACF medium was slightly, but non-significantly, higher than in Dettlaff's solution. Supplementation of the GFACF medium with antibiotics, Hepes or BSA increased the viability of chilled embryos, but the tested vitamin E analogue Trolox, vitamin C or Tris concentration had no effect on embryo viability. The outcome of this series of experiments shows that heartbeat-stage goldfish embryos could be chilled for 60 h in GFACF supplemented with 25 mm Hepes, 100 U/ml penicillin, 10 μg/l streptomycin and 1 g/l BSA in such a way that embryonic development does not proceed, and viability is not lost.

Specific activation requirements of zona-free sheep oocytes before and after somatic cell nuclear transfer

In this study, the effect of the steps involved in zona-free somatic cell nuclear transfer (SCNT) on oocyte transcripts was investigated in sheep. To establish the reliable combined electrical-chemical activation for zona-free oocytes, oocytes were first exposed to an electrical pulse and then treated with 18 chemical activation regimens designed through modifying duration and concentration of ionomycin and 6-dimethyl aminopurine (6-DMAP), which is routinely used for SCNT. Electrofusion-mediated nuclear transfer significantly reduced transcript abundances of CCNB1, POU5F1, NPM2, GMMN, and CX43 compared to intact oocytes. Maximum parthenogenetic blastocyst development was obtained when oocytes were submitted to electric pulse and then to (1) 5 μM ionomycin for 5 or 2.5 min, both followed by 2 h of incubation with 6-DMAP (41.7±1.1, and 42.4±1.4%, respectively), (2) 5 μM ionomycin for 1 min+6-DMAP for 4 h (43.1±1.4%), and (3) 2.5 μM ionomycin for 1 min+6-DMAP for 2 h (42.4±1.4%), with significant differences compared to all the other groups. Statistical assessment of interactions between duration and concentration of ionomycin and duration of 6-DMAP exposure revealed that (1) concentration of ionomycin may be a more important factor than its duration, (2) both a long exposure period and a low concentration of ionomycin had marked decreasing effects on parthenogenetic development of zona-free oocytes, and (3) high duration of exposure to 6-DMAP can reduce parthenogenetic development. Despite an activation preference of parthenogenetic oocytes, a significantly higher rate of cloned blastocyst development was observed when reconstructed oocytes were activated with 5 μM ionomycin for 5 min rather than 2.5 μM ionomycin for 1 min (8.8±2.5 vs. 1.25±2.2%). These results suggested that SCNT steps have determining effects on oocyte transcripts and activation preferences of the reconstituted oocytes compared to intact counterparts. In this sense, reconstituted oocytes may need a higher concentration of ionomycin for a longer period than intact oocytes.

Cryosurvival of in vitro produced embryos as affected by health status effect of oocyte donor cow

In vitro embryo production and embryo vitrification of genetically superior cows that culled inevitably due to health problems can accelerate genetic progress. This study was carried out to investigate whether maternal age and health status effects of high genetic merit cows affect cryosurvival and developmental competence of IVP embryos. In this sense, the effects of ageing and four common culling causes of dairy cows [repeat breeding (RPB), udder problems (UPM), chronic endometritis (CRE), and lameness (LAM)] on in vitro embryo development, and in vivo developmental competence after embryo vitrification were evaluated. The mean number of oocytes obtained per cow did not vary significantly between donors indifferent groups. Cleavage rates in RPB (86.0+/-4.2%), SEN (81.3+/-2.5%) and CRE (77.6+/-6.3%) cows which were comparable to control (95.9+/-1.5%) but were significantly higher than the related rate of UPM donors (50.6+/-2.6%). Importantly, there was no significant difference between the blastocyst rates of different groups. Mean overall survival rate was not different between the groups and was not affected by the blastocyst production rate. There was no significant difference between pregnancy rates of different groups. The results of the present study indicated that in cattle, neither ageing, nor these four diseases affect ovarian potential in terms of the yield and quality of in vitro embryo development.

Zeta potential vs apoptotic marker: which is more suitable for ICSI sperm selection?

PURPOSE

Selection of appropriate sperm is considered as a decision making point in the ICSI procedure. Canonically, sperm selection is based on morphology and motility. Recent advances in this field, have shown that, this procedure can be assisted by further selection based on membrane surface charge (Zeta potential) and surface apoptotic marker (phosphatidylserine externalization) using magnetic activated cell sorter (MACS). Based on the literature, both these procedures improve quality of selected sperm population. Therefore, this study aims to compare the efficiency of these two procedures.

METHODS

Semen samples were collected from 36 fertile and infertile (teratozoospermic and /or asthenozoospermic) individuals. Sperm DNA fragmentation, protamine deficiency and morphology were assessed by TUNEL, CMA3 and papanicolaou staining in unprocessed, MACS and Zeta processed samples.

RESULTS

Although both MACS and Zeta were able to separate a higher percentage of sperm with normal morphology, and lower DNA fragmentation and protamine deficiency compared to unprocessed, MACS procedure could significantly isolate, a greater percentage of sperm with normal acrosome and protamine content compared to Zeta procedure.

CONCLUSION

Both MACS and Zeta procedures improve the quality of the selected spermatozoa for ICSI. However, MACS procedure is more efficient in individuals with severe male factor infertility to select sperm with normal acrosome and protamine content but concern regarding transfer of MACS beads into the oocyte remains to be resolved.

Cloned sheep blastocysts derived from oocytes enucleated manually using a pulled pasteur pipette

The potential applications of a simplified method of somatic cell nuclear transfer (SCNT) that is improved in both efficiency and throughput is considerable. Technically, a major step of SCNT is to produce large pools of enucleated oocytes (cytoplasts) efficiently, a process that requires considerable micromanipulation skill and expensive equipment. Here, we have developed an efficient and high-throughput method of manual oocyte enucleation using a simple device, a pulled Pasteur pipette, that can be connected to standard zona-free method of embryo reconstitution. Common Pasteur pipettes were pulled on a flame to produce finely drawn pipettes with inner diameters approximately less than half the oocyte diameter (∼50-60 μm), and slightly larger than cytoplasmic protrusion (∼20-30 μm) that was induced after demecolcine treatment of MII-stage oocytes. Oocyte manipulation was performed under a stereomicroscope by either bisecting the oocyte into two approximately equal demioocytes (blind manual enucleation), or by positioning the oocytes so that the cytoplasmic extrusion that contains the MII chromosome mass is removed with the minimum amount of cytoplasm (oriented manual enucleation). The survival rate of the manually enucleated oocytes was 81.4-91.5%, comparable to standard zona-free method of oocyte enucleation (>95%). A total of 80-120 oocytes could be enucleated in 10 min, which was considerably higher than standard zona-free enucleation method. In vitro development rates of cloned embryos derived from manually enucleated cytoplasts with varying cytoplasmic volumes (50%, 95%, and 100%) was comparable, and embryonic developmental rates of the two latter groups were at least as good as standard zona-free method. The manual method of oocyte enucleation described here can be learned and mastered for simple, fast, and cheap production of cloned embryos with comparable efficiency to other available methods.

Sperm ubiquitination and DNA fragmentation in men with occupational exposure and varicocele

Assessment of sperm ubiquitination and DNA fragmentation as sperm functional markers are proposed to complement routine semen analysis. This study focuses on the evaluation of these markers in infertile men with varicocele or exposed to occupational background. The results were compared with normozoospermic men. Semen parameters in both groups were lower than those in the control group. Ubiquitination median, as a marker for functionality of the ubiquitin-proteasome system, was also lower in both groups. The ubiquitination median showed a significant positive correlation with motility in both groups, while it showed only a negative correlation with sperm morphology in the varicocele group. DNA fragmentation showed a significant correlation with semen parameters, in total varicocele and also total exposure groups. In conclusion, significant difference of sperm ubiquitination between normal and study groups further validates that sperm ubiquitination as a potential molecular marker for sperm evaluation in addition to routine semen analysis in clinical laboratories.

Nuclear transfer technique affects mRNA abundance, developmental competence and cell fate of the reconstituted sheep oocytes

The effect of technical steps of somatic cell nuclear transfer (SCNT) on different aspects of cloned embryo development was investigated in sheep.In vitro-matured oocytes were enucleated in the presence or absence of zona and reconstituted by three different SCNT techniques: conventional zona-intact (ZI-NT), standard zona-free (ZF-NT) and intracytoplasmic nuclear injection (ICI-NT). Stepwise alterations in nuclear remodeling events and in mRNA abundances, throughput and efficiency of cloned embryo development and cell allocation of the resulted blastocysts were assessed. Early signs of nuclear remodeling were observed as soon as 2 h post-reconstitution (hpr) for fusion-based methods of nuclear transfer (ZI-NT and ZF-NT) but were not observable until 4 hpr with the ICI-NT method. The relative mRNA abundances ofHSP90AA1(HSP90),NPM2andATPasegenes were not affected by i) presence or absence of zona, ii) oocyte enucleation method and iii) nuclear transfer method. After reconstitution, however, the relative mRNA contents ofPOU5F1(OCT4) with the ZI-NT and ZF-NT methods and ofPAPOLA(PAP) with ZF-NT were significantly lower than those for the ICI-NT method. Zona removal doubled the throughput of cloned blastocyst development for the ZF-NT technique compared with ZI-NT and ICI-NT. Cleavage rate was not affected by the SCNT protocol, whereas blastocyst yield rate in ICI-NT technique (17.0±1.0%) was significantly (P<0.05; ANOVA) higher than in ZF-NT (7.1±1.5%) but not in the ZI-NT group (11.2±3.3%). Despite the similarities in total cell number, SCNT protocol changed the distribution of cells in the blastocysts, as ZF-NT-cloned blastocysts had significantly smaller inner cell mass than ZI-NT. These results indicate that technical aspects of cloning may result in the variety of cloning phenotypes.

Kit ligand and glial-derived neurotrophic factor as alternative supplements for activation and development of ovine preantral follicles in vitro

In vitro growth of preantral follicles has the potential to produce considerable numbers of competent oocytes for use in medicine, agriculture, and even wildlife conservation. The critical regulatory role of growth factors and hormones in the development of preantral follicles has been established. This study investigated the effect of glial-derived neurotropic factor (GDNF) and kit ligand (KL) on the in vitro development of ovine preantral follicles. Results indicated that both GDNF and KL significantly improved activation of primordial follicles, similar to co-addition of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF), which are commonly used for in vitro follicular development. Importantly, GDNF had a more profound effect on follicle health, development, and differentiation compared with KL alone. Furthermore, the combination of GDNF and KL in the presence of EGF and bFGF had a positive, synergic effect on health, development, and differentiation of preantral follicles, as determined by histological and hormonal assessments. The results of this study may provide a foundation for further studies that will unravel the molecular mechanisms of follicular development to further improve the current status of in vitro preantral follicle culture.

Relationship between fertilization rate and early apoptosis in sperm population of infertile individuals

Integrity of the sperm membrane, of which phosphatidyl serine (PS) plays a central role, is essential for fertilization. The externalisation of PS (EPS) occurs during capacitation and the acrosome reaction. EPS, from the inner to the outer membrane, is considered as a sign of early apoptosis. Therefore, EPS may have a dual function in sperm. This study has evaluated the relationship between EPS and fertilization, embryo quality and pregnancy outcomes in couples who were candidates for ICSI. Semen samples were collected from 43 ICSI candidates and assessed according to World Health Organization guidelines for semen parameters. EPS was assessed by Annexin V and propidium iodide (PI) staining. Protamine deficiency was assessed by chromomycin A3 (CMA3) staining. A significant positive correlation was observed between the percentages of fertilization and annexin-positive PI-negative (An(+)PI(-)) sperm. There was a significant negative correlation between the percentages of protamine-deficient sperm with the percentage of fertilization. In addition, the percentage of An(+)PI(-) sperm in individuals with fertilization rates higher and lower than 50% significantly differed. The percentage of annexin-positive PI-positive (An(+)PI(+)) sperm in semen of the partners of pregnant women significantly differed from the partners of nonpregnant women. In conclusion, if An(+)PI(-) is a sign of capacitation and An(+)PI(+) is a sign of apoptosis, the results suggest that semen samples with a higher ability to undergo capacitation have a higher chance to result in successful fertilization post-ICSI. The presence of a high percentage of apoptotic sperm in the insemination sample before capacitation may reduce the chances of pregnancy.

Vitrification of in vitro produced bovine embryos: effect of embryonic block and developmental kinetics

In order to investigate whether the kinetics and stage of embryo development affect cryosurvival of in vitro produced bovine embryos, cleaved embryos were categorized in six groups based on their developmental kinetics regarding the stage of embryonic block in bovine (8-16 cell stage): I and II--early (day 2) and late (day 3) 5-8 cell, III and IV--early (day 3) and late (day 4) 8-16 cell, and V and VI--early (day 4) and late (day 5) morula. The cryosurvival and developmental competence of these embryos were compared with each other and also with the corresponding control groups. The potential of 5-8 cell stage embryos to survive vitrification and further develop towards blastocyst stage was significantly lower than vitrified and un-vitrified 8-16 cell and morula stage embryos. These results suggest that, the survival rate and potential of embryos to develop towards blastocyst stage might be affected by the kinetic of the embryo development. Moreover, the results of this study indicated that the optimal stages of early embryo vitrification are post-embryonic block.

Is there an association between HOST grades and sperm quality?

BACKGROUND

Intracytoplasmic sperm injection (ICSI) is the primary treatment for male infertility. However for this procedure, with the exception of visual morphological selection, there is no standardization for sperm selection. Recently, the hypo-osmotic swelling test (HOST) has been proposed to potentially select sperm with intact membranes. The aim of this study is to evaluate the ability of this technique to select functional sperm in terms of apoptosis and morphology, as well as nuclear integrity.

METHODS

A total of 20 semen samples were randomly collected from men who attended the Andrology Unit of the Isfahan Fertility and Infertility Center. Semen samples were washed and exposed to hypotonic conditions, before being fixed and simultaneously assessed for membrane integrity as well as abnormal morphology, DNA fragmentation and protamine deficiency by using Papanicolaou, TUNEL and CMA3 staining techniques, respectively. The remaining semen samples were washed with calcium buffer and stained by Annexin V, then exposed to hypotonic conditions before being assessed for early apoptosis along with membrane integrity.

RESULTS

HOST grade 'd', followed by grade 'c', showed the highest percentages of healthy sperm, whereas sperm of HOST grade 'g' in which anomalies in terms of apoptosis, abnormal head morphology or nuclear immaturity or membrane damage, were most frequently observed in the samples assessed.

CONCLUSIONS

Integration of HOST into the sperm selection procedure may provide a valuable tool for selection of functional sperm required for ICSI. According to this study, insemination of HOST grade 'g' sperm should be avoided during ICSI.

Functional expression of potassium channels in cardiomyocytes derived from embryonic stem cells

Royan B(1) stem cell can be differentiated to specialized cell types including cardiomyocytes. This developmental change is accompanied with expression of various K(+) channel types. The aim of this study was to detect functional expression of K(+) currents from stem cell stage and one week and two weeks after differentiation into cardiomyocyte. Mouse stem cell derived cardiomyocytes (ES-cardiomyocytes) were isolated to single cell suspension for K(+) current recording using whole cell patch-clamp technique. The predominant depolarizing current in ES-cardiomyocytes was a tetraethylammonium (TEA) (10 mM) sensitive current which was partially blocked by nifedipine (1 μM) and attenuated by increasing concentration of EGTA (10 mM) in the pipette solution. Pharmacology and electrophysiological properties of this oscillatory sustained current very well matched with characteristics of Ca(2+) activated K(+) current. In addition there was another kind of sustained outward K(+) current which was resistance to TEA but was inhibited by 3,4-diaminopyridine. The characteristic features of this current indicate that this current was due to activation of delayed rectifier K(+) channels. RT-PCR study also confirmed expression of these two types of K(+) channels in ES-cardiomyocytes. Therefore, present study shows functional expression of two types of K(+) ionic current in ES-cardiomyocytes.

High total acrosin activity in varicocele individuals

Varicocele is a common cause of male infertility and reports indicate that varicocelectomy has a beneficial effect on male fertility. The aims of this study were to evaluate and compare the total acrosin activity along with DNA integrity in semen samples obtained from 70 varicocele individuals with male factors infertility presenting grades II and III varicocele before and after the surgery and 30 fertile individuals without any clinical presentation of varicocele. Total acrosin activity, protamine deficiency, DNA fragmentation, and semen parameters including sperm concentration, motility and sperm morphology were assessed by spectrophotometery, CMA3 staining, terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay and WHO criteria, respectively. Total acrosin activity (P = 0.03), percentage CMA3 positivity (P = 0.00) and TUNEL-positive spermatozoa (P = 0.04) were higher in the varicocele individuals before the surgery compared with the fertile individuals; yet, all the aforementioned criteria decreased significantly after surgery (P < 0.05). The results of this study reveal that DNA fragmentation and protamine deficiency, as negative parameters in fertility, improve post-surgery; however, total acrosin activity as a positive parameter in fertility is higher in the varicocele individuals compared with fertile and decreases to a value close to the fertile control post-surgery. High levels of total acrosin activity in varicocele individuals need more research in future.

Zaditen (Ketotifen), as mast cell blocker, improves sperm quality, chromatin integrity and pregnancy rate after varicocelectomy

Surgery is considered the most common choice for the treatment of male infertility with clinical varicocele. Increased numbers of mast cells (MCs) have been associated with different types of infertility, including varicocele. Despite there being different reports on improved fertility following administration of MC blockers, there is no report on the effect of a MC blocker on varicocele or after varicocelectomy. Therefore, the aim of this study was to evaluate the effect of Zaditen on semen quality, protamine content, DNA damage and fertility post-surgery. The study included 103 infertile men who were referred to Isfahan Fertility and Infertility Center for varicocelectomy. Varicocele individuals were randomly divided into control (52) and treatment groups (51). Semen parameters, WBC/mL, protamine content (chromomycin A3 staining) and DNA integrity (sperm chromatin dispersion test) were assessed before and 3 months after surgery. Comparison of the aforesaid parameters between the two groups revealed significant improvement in the treatment group compared with the control group, with the exception of DNA integrity. In addition, the cumulative pregnancy significantly improved by 9 months post-surgery in the treatment group (41.17%) compared with the control group (21.15%). The results of this study, for the first time, reveal that MC blockers such as Zaditen improve semen parameters, chromatin integrity and pregnancy rates when administered as adjunct therapy post-varicocelectomy.

Quantitative expression of phospholipase C zeta, as an index to assess fertilization potential of a semen sample

BACKGROUND

Failed fertilization post-ICSI has been mainly attributed to the sperm's inability to induce oocyte activation. Phospholipase C zeta (PLCζ) is considered to be one of the factors for the induction of oocyte activation. The aim of this study was to quantitatively assess the expression of PLCζ in globozoospermic men or those with previously low or failed fertilization in comparison with fertile men or those with high fertilization potential. In addition, the relationship between expression of PLCζ and that of other sperm markers was evaluated.

METHODS

Real-time PCR was carried out to evaluate relative expression of PLCζ mRNA. Chromatin maturity and acrosin activity were assessed by CMA3 staining and a colorimetric method.

RESULTS

The expression of PLCζ was significantly lower in globozoospermic men (P< 0.01, n= 8) or individuals with previously low or failed fertilization (P< 0.01, n= 36) in comparison to fertile men (n= 24). In addition, a significant difference was observed between globozoospermic (P< 0.01) and individuals with previously low or failed fertilization (P= 0.003) in comparison to high fertilization individuals (n= 17). Expression of PLCζ was not correlated with either chromatin maturity or acrosin activity. However, a significant correlation was observed between the percentage of fertilization and relative expression of PLCζ (r= 0.4, P< 0.01).

CONCLUSION

In this study, for the first time, we have shown that assessment of relative expression of PLCζ may provide a useful marker for the ability of sperm to induce oocyte activation after ICSI.

In vitro comparison of egg yolk-based and soybean lecithin-based extenders for cryopreservation of ram semen

Substitution of egg yolk with soybean lecithin may reduce hygienic risks in extenders. Though a few studies have been performed on the effect of soybean lecithin in bull, to date evaluation of ram semen in vitro fertility after cryopreservation with use of soybean lecithin has not been studied. This study assessed the effect of 1% or 2% (wt/vol) soybean lecithin (L1 or L2) or 15% or 20% (vol/vol) egg yolk (E15 or E20) supplemented with 5% or 7% glycerol (G5 or G7) in a Tris-based medium for cryopreservation of ram (Oviss arries) semen. Although no significant difference was observed in pattern of capacitation, the best results in terms of sperm motility, viability postthaw, and cleavage rates were observed with L1G7 (51.9+/-4.8%, 48.1+/-3.5%, and 79.6+/-3.9%, respectively) and E20G7 (51.8+/-2.9%, 46.7+/-4.0%, and 72.9+/-6.4%, respectively). Our results also showed that 1% lecithin and 20% egg yolk was superior to 2% lecithin and 15% egg yolk. In terms of cleavage rate, 7% glycerol was superior to 5% glycerol. No significant difference was obtained between groups in terms of blastocysts rate per cleaved embryo. Therefore, we concluded that the optimal concentration of lecithin and egg yolk is 1% and 20%, respectively, along with 7% glycerol. In addition, our results suggest that lecithin can be used as a substitute for egg yolk.

Optimized combined electrical–chemical parthenogenetic activation for in vitro matured bovine oocytes

Sperm-mediated oocyte activation is a complex procedure, both in steps and duration, not yet been completely mimicked during in vitro studies, e.g., parthenogenesis or somatic cell nuclear transfer. Furthermore, parthenogenetic studies have been recognized as a suitable model for studying activation efficiency for nuclear transfer cloning. This study, therefore, was conducted to develop an optimized artificial activation method, based on bovine cloning. In vitro matured bovine oocytes were initially exposed to electrical pulse, used for cell fusion during cloning, and then treated with 15 temporal sequential combinations of 3 chemical activators [calcium ionophore (CI), strontium (SR) and ethanol (ET)], followed by exposure to a protein kinase inhibitor or used for in vitro fertilization as control group. Treated and naturally fertilized oocytes were further cultured for up to 8 days. Embryo development was scored daily and blastocyst cell counting was carried out using differential staining at day 8 of culture. Among 15 temporal sequential combinations of three chemical activators, the best cleavage rates were associated with double (SR-CI, 84.4%), triple (CI-SR-ET, 79.4%) and single (CI, 73.7%) compounds, respectively, which were not significantly different with each other and with in vitro fertilized (IVF) (85.5%). The highest blastocyst rates were gained with ET-SR (24.5%), SR-CI-ET (20.4%) and CI (24.5%) accordingly which were not significantly different with each other but significantly lower than IVF (47%). Embryo cell counting further confirmed reasonably better quality of blastocysts produced using double, triple and single compounds. Although most of the sequential artificial activation compounds induced high cleavage rate, close to IVF, but this did not assure comparable further embryo development to the blastocyst stage. Nevertheless, the results suggest exposure of in vitro matured bovine oocytes to electrical pulse, followed by exposure to CI-6-dimethylaminopurine (6-DMAP) or ET-SR-6-DMAP could be regarded as the optimal artificial activation protocol for in vitro development of parthenogenic bovine oocytes or as a step for activation protocol in cloning procedure.

Evaluation of sperm selection procedure based on hyaluronic acid binding ability on ICSI outcome

PURPOSE

To compare the efficiency of routine sperm selection method with HA-selection procedure for fertilization rate, embryo development, implantation and pregnancy rates as well as evaluating the relationship between HA-binding ability with sperm protamine deficiency and DNA fragmentation.

METHODS

Semen samples were obtained from the 50 couples undergoing ICSI. The percentage of fertilization rate, cleavage and quality of embryos compared between two procedures (routine sperm selection and HA-binding selection). The semen samples were assessed for DNA fragmentation and protamine deficiency by sperm chromatin dispersion (SCD) test and Chromomycin A3 (CMA3) staining, respectively.

RESULTS

A significant inverse correlation was observed between percentage of HA binding with protamine deficiency, DNA fragmentation and abnormal sperm morphology (P < 0.05). Furthermore, in current study, oocytes inseminated by HA sperm selection procedure had significantly higher fertilization rate (P < 0.05). While the pregnancy and implantation rates were insignificantly increased.

CONCLUSION

The results suggest that normal sperm have higher chance to bind HA and therefore, HA sperm selection procedure may select sperm with normal protamine content and low DNA fragmentation, but to confirm the effect of HA sperm selection on the ICSI outcome requires further studies.