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] supplementationto the In Vitro Maturation [IVM] and In Vitro Culture [IVC] media ofvitrified-warmed ovine oocytes on their developmental competence and expression ofNa +/K +/ATPase in resulting embryos

Methods: The slaughterhouse-derived immature oocytes [n=1069] were randomly distributedinto four experimental groups: groups I and II] IVM/IVF and IVC of fresh andvitrified oocytes without angiotensin supplementation [Control-Fresh and Control-Vitgroups, respectively]; group III] IVM of vitrified oocytes in the presence of Ang II followedby IVF/IVC [Vit-IVM group]; and group IV] IVM/IVF of vitrified oocytes followedby 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 +/ATPasealpha 1andbeta 1 subunits

Results: In Vit-IVM and Vit-D4 groups, the rates of expanded and total blastocysts onday 7 as well as the proportion of blastocysts on day 8 were increased. The expressionof Na +/K +/ATPasealpha 1 andbeta 1 subunits were positively influenced by the addition of AngII on day 4 [Vit-D4 group].Conclusion: The addition of Ang II to the IVM and IVC media could improve blastocystsformation in vitrified sheep oocytes. This improvement might be related to thegreater expression of Na +/K +/ATPasealpha 1 andbeta 1 subunits when Ang II was added duringIVC

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 alpha 1 and beta 1 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 alpha 1 and beta 1 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 alpha 1 and beta 1 subunits when Ang II was added during IVC

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

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

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

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

Culture of ovine IVM/IVF zygotes in isolated mouse oviduct: effect of basal medium

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

technique for facile and precise transfer of mouse embryos

Successful Embryo Transfer [ET] technique is a fateful step of all efforts to achieve live births from in vitro produced embryos in assisted reproductive techniques or in knockout, transgenic or cloned animal projects. Small reproductive tract of mice and limitation of current techniques may not well satisfy the requirements for mass production of genetically modified mice. Genetic abnormalities of embryos, receptivity and uterine contractions, expulsion of embryos, blood, mucus or bacterial contamination on the transfer pipette tip, technical problems and even animal strain may affect embryo transfer outcome. In this study, two techniques of embryo transfer in mice were compared. In conventional technique the oviduct wall was punctured with a 30-gauge needle and the loaded Pasteur pipette with embryos and medium was inserted into the hole. In new technique, embryos that were loaded in modified micropipette with minimal medium were transferred directly to the oviduct by manual piston micro-pump easily. Embryo viability was evaluated considering the percentage of live healthy newborns. Results of the two techniques were compared by t-test within the NPAR1WAY procedure of SAS software [ver. 9.2]. The average live birth rates in the novel methods was significantly higher [42.4%] than the conventional method [21.7%, p<0.05]. In conclusion, using new embryo transfer technique improved birth rate by preventing embryos expulsion from the oviduct, saving time and easy transfer of embryos with minimum volume of medium

Regulations and ethical considerations in animal experiments: international laws and islamic perspectives

Growing usage of animals in the research projects has drawn more attention to their welfare and ethics surrounding this practice. Dissemination of information about the existing ethical consideration and alternatives in animal experiments has two important functions; first, it increases the researcher's awareness of the possible methods of using animals in the experiment, and second, to ensure that potential users are aware of the established alternatives. For example, legislations enacted in many countries during the 1980s state that laboratory animal applications should be reduced, refined and replaced wherever possible according to principles of the 3Rs. Thus, scientists around the world tried to apply the 3Rs in their biomedical researches regarding welfare of the laboratory animals. However, the Qur'an, the holy book of Muslims, and also Hadiths contain the obligatory ways to keep and treat animals since their revelations. According to Islamic viewpoint, animals represent Allah's ability and wisdom, and humans must pay attention to their health and living conditions. Several Islamic manuscripts state that animals have their own position in the creation hierarchy and humans are responsible for supplying minimal facilities and their welfare. This paper has tried to review ethical consideration in animal experiments and regarding Islamic resources in this case to encourage providing comprehensive ethical regulations in animal experiments which its establishment could be beneficial for animal ethics committees or research institutes

[Effect of Environmental Risk Factors on Human Fertility]

Infertility is believed to be part of the various medical problems that has increased up to 50% since 1955 in the world and 10-15% of couples are already suffering from it. Development of industrialization and urbanization in human societies have dramatically changed the human life style and led gradually to the increase of various environmental risk factors. Humans are exposed to polluted air, containing harmful elements such as lead, drinking water which is frequently contaminated by different noxious materials like arsenic, chromium, benzene, agricultural water and soil containing pesticides and chemical fertilizers - which subsequently will produce contaminated crops - use of hormones and drugs in animal husbandries and presence of their residues such as steroidal hormones in meat and dairy products, the ever-growing use of synthetics and preservatives in food industry. Furthermore, poor dietary habits and malnutrition, consumption of diets deficient in antioxidants, zinc, selenium and copper, adverse effects of some pharmaceutical products and chemical agents such as ketoconazole and dioxin, daily exposure to harmful radiations such cosmic, ultraviolet and X rays, electromagnetic waves emitted from telecommunication transmitters and cell-phones, physical and psychological stresses in living and working environments, smoking, stationary life-style, obesity, and the increasing age of marriage all are the factors which can directly and indirectly affect human fertility. Although measuring environmental hazards and studying their effect on fertility reduction is difficult due to their multifactorial and diverse nature, the problem still remains indeterminate and more studies are required to draw a strong conclusion. The purpose of this review was to study the effects of environmental risk factors, especially emerging risk factors, on decreasing human fertility