فهرست مطالب banafsheh heidari

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.

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.

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).

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.

The aim of our study was to evaluate the effectiveness of Ginger in improving sperm fertility indices in poultry. Ginger extract (0.5, 1.0 and 2.0 g/L, for two weeks) was added to the drinking water of 36 adult roosters. Then, specific sperm fertility indices including percentage of motile sperm, fast progressive movements, slow progressive movements, abnormal movements, active sperm and specialized sperm motility index were measured. Hematology indices, immunity titer against Newcastle disease vaccine and testis weight were also determined. The highest number of sperms with fast progressive movements, the highest amount of active and motile sperms and the lowest amount of structural and motor abnormalities of sperm were observed in concentrations of 1 and 2 g/L. Ginger had no effect on hematology, immunity and testis weight. Adding Ginger to the diet of breeder roosters can improve sperm fertility, which leads to increased hatchability.

Medicinal plants with antioxidant properties can quantitatively and qualitatively improve the sperm fertility indicators and increase sperm fertilization in roosters by disrupting the production of free radicals and neutralizing oxidative stress. The aim of this study was to investigate the effect of different concentrations of ginger extract on the biological parameters of Golpayegani rooster sperm. In this study, the hydroalcoholic extract of ginger in concentrations of 0, 500, 1000 and 2000 mg / L was prepared and added to the drinking water of 36 adult male Golpaygani roosters for four weeks. After four weeks, the effect of different concentrations of the extract on sperm biological parameters (number, total motility, survival and normal morphology) was investigated and compared. Papanicolaou staining was used to evaluate a variety of abnormalities in different parts of the sperm. The results showed that adding ginger extract in all concentrations to drinking water significantly increased the overall motility of sperm and the percentage of sperm with normal morphology. However, a significant increase in the total number of sperm with high viability requires the addition of high doses of the extract (1000 and 2000 mg). There was no significant difference in some of the above indicators between the mean and high concentrations of the extract (P>0.05). In general, continuous consumption of ginger significantly increases the quantitative and qualitative indicators of rooster sperm and plays a role in the improvement of fertility in rooster.

Antioxidants can disrupt the production of free radicals by neutralizing oxidative stress and increase the proliferation of testicular germ cells and then improve the quality and quantity of sperm fertility indices in breeder chickens. The knotgrass extract (Polygonum avicular) has high levels of phenolic and flavonoid compounds and has high antioxidant properties. This study aimed to investigate the effect of knotgrass extract on the biological parameters of sperm in roster. In this study, hydroalcoholic extracts of knotgrass was prepared in four concentrations of zero, 500, 1000 and 2000 mg/L and added to drinking water for adult Golpayegan official breeders for one week. After one week, the effect of different doses of the extract on the biological parameters of sperm (number, mobility, survival and normal sperm morphology) was evaluated and compared. The Papanicolaou staining was also used to evaluate the sperm abnormalities. The most number of live sperm with the highest motility and normal morphology was observed in group receiving 2000 mg/L of knotgrass extract. Also, application of high dosage of extract significantly reduced the head, middle piece and tail abnormalities of sperm (P≤0.05). The highest number of live sperm with the highest motility and normal morphology was observed in the group receiving 2000 mg/L of knotgrass extract. Also, using high dose of extract significantly reduced head, medulla, and sperm motility abnormalities (P≤0.05). In overall, the use of hydroalcoholic extracts of knotgrass improved some of the biological parameters of sperm. It can be concluded that knotgrass (Polygonum avicular), due to high amount of phenolic and flavonoid antioxidant compounds, improves the sperm quality in fowls.

Electroporation can be a highly efficient method for introducing the foreign genetic materials into the targeted cells for transient and/or permanent genetic modification. Considering the application of this technique as a very efficient method for drug, oligonucleotide, antibody and plasmid delivery for clinical applications and production of transgenic animals, the present study aimed to optimize the transfection efficiency of sheep testicular cells including spermatogonial stem cells (SSCs) via electroporation.
This study is an experimental research conducted in Biotechnology Research Center (Avicenna Research Institute, Tehran, Iran) from September 2013 to March 2014. Following isolation and propagation of one-month lamb testicular cells (SSCs and somatic testicular cells including; Sertoli, Leydig, and myoid cells), the effect of different electroporation parameters including total voltages (280, 320, and 350 V), burst durations (10, 8, and 5 milliseconds), burst modes (single or double) and addition of dimethyl sulfoxide (DMSO) were evaluated on transfection efficiency, viability rate and mean fluorescent intensity (MFI) of sheep testicular cells.
The most transfection efficiency was obtained in 320 V/8 milliseconds/single burst group in transduction medium with and without DMSO. There was a significantly inverse correlation between transfection efficiency with application of both following parameters: addition of DMSO and double burst. After transfection, the highest and lowest viability rates of testicular cells were demonstrated in 320 V/8 milliseconds with transduction medium without DMSO and 350 V/5 milliseconds in medium containing DMSO. Addition of DMSO to transduction medium in all groups significantly decreased the viability rate. The comparison of gene expression indicated that Sertoli and SSCs had the most fluorescence intensity in 320 V/double burst/DMSO positive. However, myoid and Leydig cells showed the maximum expression in 320 V/single burst and/or 350 V/double burst/ DMSO positive.
We optimized the electroporation method for transfection of sheep testicular cells and recommended the application of 320 V/8 milliseconds/single pulse/DMSO negative for transduction of plasmid vector into these cells. Among testicular cells, the most external gene expression was demonstrated in SSC population.

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 Naﲯ뼁㏚ in resulting embryos.
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 Naﲯ뼁㏚ α1 and β1 subunits.
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 Naﲯ뼁㏚ α1 and β1 subunits were positively influenced by the addition of Ang II on day 4 (Vit-D4 group).
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 Naﲯ뼁㏚ α1 and β1 subunits when Ang II was added during IVC.

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. 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. 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). 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.

Poly vinyl alcohol/Chitosan nanofibrous mat were prepared by electrospinning method with suitable pore sizes as potential matrices for soft tissue engineering. The designed scaffolds by electrospinning method evaluated by differentanalyses such morphological, mechanical, and cellular analysis.Microscopic results showed diameters of poly vinyl alcohol/Chitosan nanofibers were approximately 150 nm. Mechanical investigations illustratedstress - strain curve of poly vinyl alcohol /chitosan mat indicate good flexibility with average strain and good percentage of yield stress. The cellular resultsrevealthat addition of chitosan to poly vinyl alcohol enhances viability and proliferationof fibroblast cells, which increases the biocompatibility of the scaffold. In fact, addition of a smallpercentage of chitosan to the poly vinyl alcoholproved to be a promising approach for designof a scaffold.

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

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. 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). 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. 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/cm2 density. Moreover, the adipose tissue derived MSCs had the lowest proliferative indices.

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. 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. 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. 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.

The term “Cloning” has originated from “Klon”, a Greek word with the meaning of a small twig that can multiply by itself and turn to a generative tree. Cloning is an asexual reproduction in which a copy or multiple copies of an organism are generated by transferring the nucleus (DNA) of a somatic cell into an enucleated metaphase-II oocyte. Despite the benefits and potentially broad applications of this technology, its low efficiency, especially in the production of viable offspring, has implicated its application with serious challenges. In this article, we will review papers related to its emerging principles, with an emphasis on epigenetic modifications, which appear to govern the efficiency of cloning. The literature review was carried out by searching through knowledge-based data bases such as ScienceDirect, PubMed and Scopus on the internet. No time limit was considered for literature review of the relevant articles up to the time of submission. Considering the large varieties of factors affecting cloning, improvements in cloning efficiency are dependent on the increment of theoretical knowledge and technical expertise of its procedures. This can be achieved by improving oocyte and cytoplasmic maturation, optimizing synchronization between the nucleus of the donor cell and cytoplasm of MII stage oocyte, minimizing the physical insults to the cytoskeleton of oocyte during enucleation and nuclear transfer, improving the cellular fusion and culture conditions of reconstructed oocytes and in particular and more importantly by employing effective methods to qualitatively alter the epigenetic status of the incoming nucleus to an embryonic or totipotent state, leading to the improvement of donor cell reprogramming. Considering the importance of inherited maternal transcripts and proteins in cytoplasm of fully matured oocytes in supporting the embryos up to the embryonic genomic activation (EGA) and the capability of MII stage cytoplasm in de-differentiating mammalian somatic cells and coincident of EGA with depletion of maternally originated transcripts, reprogramming of the somatic cell nuclei must be completed by the time that the embryonic genome is activated. Since the patterns of epigenetic modification are dynamic and not static during development, the optimum procedure to properly induce nuclear reprogramming should follow the pattern of epigenetic modifications in normal embryo development. Besides the all progresses in reproductive cloning using highly efficient methods, any deviation from the normal pattern of mRNA expression due to epigenetic changes induced by chemical interventions in early preimplantation embryo may persist throughout fetal development. The effects of these aberrations may manifest later in development. Nonetheless, understanding the kinetics of normal molecular events related to epigenetic modifications and identification of the specific factors present in the ooplasm, which are necessary for epigenetic reprogramming, will provide a better understanding of the underlying mechanisms and would improve cloning efficiency and other related technologies.

Improvements on embryo micromanipulation techniques led to the use of embryo biopsy in commercial embryo transfer programs for genetic analysis of preimplantation bovine embryos. The aim of this study was to evaluate the quality of bovine blastocyst derived from embryos biopsied at different precompacted morulae stages by assessment of cryosurvivability of the resulting blastocysts. The in vitro produced bovine embryos were subjected to biopsy at days 2, 3, and 4 post-insemination with different cell numbers (4 to 16-cells). Embryo cell biopsy was carried out in a 100 l drop of H-SOF following pronase drilling by aspiration of one blastomere. The biopsied embryos were then cultured in SOFaaBSA co-cultured with oviduct cells-monolayer until blastocyst formation. The blastocysts were cryopreserved at room tempera-ture after exposure of equilibration (glycerol 1.4 M for 5 min and then glycerol 1.4 M and ethylene glycol 3.6 M for 5 min) and vitrification solutions (3.4 M glycerol and 4.6 M ethylene glycol). The blastocysts were loaded into the center of 0.25 ml straws separated by air bubbles from 2 columns of sucrose 0.5 M and plunged immediately into liquid nitrogen. There was no significant difference in cryosurvivability of vitrified-warmed blastocysts derived form biopsied embryos at different pre-compacted morula stages. The quality of biopsy derived blastocysts was identical to that of non-biopsy derived ones in terms of post vitrifcation survival and hatching rates. In conclusion there was no preference between different times of embryo biopsy at precompacted morula stages in term of cryosurvivability of biopsy derived bovine blastocysts.

Embryo biopsy has potential applications in molecular research processes in domestic animals, besides its application in sex determination in embryo transfer programs. The objective of the present study was to assess the in vitro development of bovine embryos biopsied on different days of precompacted morula stage. Slaughterhouse-derived oocytes were matured in vitro, fertilized (Day-0) by frozen-thawed, Percol-separated spermatozoa and cultured on oviductal cell monolayer. The embryos were subjected to cell biopsy on Days 2, 3, and 4 postinsemination at 4-16-cell stages. The data were analyzed using ANOVA and Chi-squared tests (SigmaStat, version 2). A p-value < 0.05 was considered significant. Biopsies carried out at 16-cell stage (Day-4) resulted in 94% of embryos developing to the blastocyst stage, which was significantly higher (p < 0.05) than the ones biopsied at 8-cell stage on Day-4 (64%), and those undergoing the procedure on Day-3 (49% and 46% at 4-cell and 8-cell stages, respectively) and Day-2 (39% and 33% at 4-cell and 8-cell stages, respectively). No significant differences were observed between biopsied and non-biopsied embryos on a given day. The total cell number in biopsy-derived blastocysts ranged between 103 and 135. The difference in the number of total cells, dead cells and cell allocation to trophectoderm and inner cell mass between non-biopsied and biopsy-derived blastocysts was insignificant. Biopsy of bovine embryos at 4-16-cell stages had no adverse effects on in vitro developmental potentials and the 16-cell stage embryos, biopsied on Day-4 was the best stage for blastomere removal.