Transcriptome profiling of gonad-stimulating factors in thoracic ganglia and a potential role of Indian hedgehog gene in vitellogenesis of banana shrimp Fenneropenaeus merguiensis

Shrimp reproduction is controlled by several factors. Central nervous tissues, especially thoracic ganglia and brain, are known sources of gonad stimulating factors (GSFs) in crustaceans, but the GSFs in shrimp have not yet been clarified. Hence, we aimed to characterize and study putative GSFs from thoracic ganglia of adult female Fenneropenaeus merguiensis. An analysis of thoracic ganglia transcriptome revealed 3224 putative GSFs of a total 77,681 unigenes. Only 376 putative GSFs were differentially expressed during ovarian developmental stages. Eight candidate GSFs were validated for their expression patterns in thoracic ganglia, including the Indian hedgehog gene. F. merguiensis Indian hedgehog (FmIHH) was then investigated for its role in vitellogenesis. The obtained full-length cDNA of FmIHH was similar to other crustacean IHHs rather than Sonic and Desert HHs. The FmIHH was dominantly expressed in thoracic ganglia, and its expression was significantly increased in the vitellogenic stages before being downregulated at the mature stage of ovarian development. Injection of the recombinant FmIHH (His-TF-IHH) protein stimulated vitellogenin expression in ovaries on day 3 and 7, and also increased the gonadosomatic index. In addition, crustacean hyperglycemic hormone expression and total sugar were significantly decreased in eyestalks and hemolymph, respectively, after injection of His-TF-IHH, while lactic acid was increased. Both total sugar and lactic acid were unchanged in ovaries of His-TF-IHH injected shrimp. These results suggested that FmIHH plays a crucial role in vitellogenesis and regulate sugar uptake during ovarian development.

Anethole improves the developmental competence of porcine embryos by reducing oxidative stress via the sonic hedgehog signaling pathway

BACKGROUND

Anethole (AN) is an organic antioxidant compound with a benzene ring and is expected to have a positive impact on early embryogenesis in mammals. However, no study has examined the effect of AN on porcine embryonic development. Therefore, we investigated the effect of AN on the development of porcine embryos and the underlying mechanism.

RESULTS

We cultured porcine in vitro-fertilized embryos in medium with AN (0, 0.3, 0.5, and 1 mg/mL) for 6 d. AN at 0.5 mg/mL significantly increased the blastocyst formation rate, trophectoderm cell number, and cellular survival rate compared to the control. AN-supplemented embryos exhibited significantly lower reactive oxygen species levels and higher glutathione levels than the control. Moreover, AN significantly improved the quantity of mitochondria and mitochondrial membrane potential, and increased the lipid droplet, fatty acid, and ATP levels. Interestingly, the levels of proteins and genes related to the sonic hedgehog (SHH) signaling pathway were significantly increased by AN.

CONCLUSIONS

These results revealed that AN improved the developmental competence of porcine preimplantation embryos by activating SHH signaling against oxidative stress and could be used for large-scale production of high-quality porcine embryos.

Expression profiles of circular RNA in human placental villus and decidua and prediction of drugs for recurrent spontaneous abortion

PROBLEM

We aimed to evaluate potential biomarkers and candidate drugs for recurrent spontaneous abortion (RSA) and explore functional circular RNA pathways involved in regulating RSA.

METHOD OF STUDY

Expression profiles of placental villus and decidua samples derived from females with RSA and those with healthy pregnancies who underwent induced abortion were analyzed using high-throughput RNA whole transcriptome sequencing. Abnormally expressed circular RNAs in a larger cohort of samples were validated using real-time quantitative polymerase chain reaction. Drug discovery and molecular docking were performed using online databases and the Autodock tool, respectively.

RESULTS

In total, 2103 and 2160 circular RNAs were detected in three pairs of villi and three pairs of decidual tissues, respectively. A total of 22 circular RNAs, 58 miRNAs, and 393 mRNAs with significantly different expression patterns were identified. Five circular RNAs were verified, and the expression of hsa_circ_0088485 was significantly upregulated in the RSA group (P = .041) with a high area under the curve value (.727), sensitivity (76.5%), and specificity (64.7%). GO and KEGG enrichment analyses indicated that differentially expressed genes were associated with angiogenesis and cell adhesion. Drug discovery and molecular docking were analyzed based on 93 differentially expressed mRNAs of the ceRNA network. A total of 36 chemicals were identified as putative bioactive molecules for RSA, and one representative chemical was identified for docking with six proteins.

CONCLUSIONS

These findings provide novel insights into the mechanism of regulation of RSA by circular RNA and its clinical diagnosis and treatment.

Paeoniflorin improves the in vitro maturation of benzo(a)pyrene treated porcine oocytes via effects on the sonic hedgehog pathway

Benzo(a)pyrene (BaP) is a toxic substance that people are often exposed to. It has serious harmful effects on the body, and has a destructive effect on oocytes and cumulus cells. Here, we found that paeoniflorin (Pae), a traditional Chinese medicine monomer with antioxidant effects, decreased BaP-induced meiotic failure by increasing the activity of the Sonic hedgehog (SHH) signaling pathway and reducing the level of reactive oxygen species (ROS). We found that the in vitro maturation (IVM) rate was significantly increased (P < 0.05) in the 0.1 μM Pae and BaP (co-treatment) group compared with BaP group due to reduced ROS levels and increased mitochondrial membrane potential (ΔΨ) and ATP content. The mRNA expression levels of oocyte maturation and cumulus cell expansion-related genes were also significantly higher in the co-treatment group. To demonstrate the quality of oocytes, the development capacity of parthenogenetically activated (PA) and in vitro fertilization (IVF) embryos from different treatment groups oocytes were determined.The blastocyst formation rate was significantly higher in PA and IVF embryos derived from oocytes in the co-treatment group than in those derived from oocytes in the BaP group. To further confirm that the SHH signaling pathway was involved in causing these effects of Pae, we treated oocytes with Pae and BaP in the presence or absence of cyclopamine (Cy), an inhibitor of this pathway. Cy abolished the effects of Pae in BaP treated porcine oocytes. In conclusion, Pae improves the IVM capacity of BaP-treated porcine oocytes by activating the SHH signaling pathway, inhibiting ROS production, and increasing ΔΨ.

The effect of heat stress on proliferation, synthesis of steroids, and gene expression of duck granulosa cells

Granulosa cells (GCs) play an important role in the development of follicles. In this study, we investigate the impact of heat stress at 41°C and 43°C on duck GCs' proliferation and steroids secretion. And, the transcriptomic responses to heat treatment were examined using RNA-sequencing analysis. Digital gene expression profiling was used to screen and identify differentially expressed genes (fold change ≥ 2 and Q value < 0.05). Further, the differential expression genes (DEGs) were classified into GO categories and KEGG pathways. The results show that duck GCs blocked in the G1 phase were increased on exposure to heat stress. Meanwhile, the expression of proliferative genes, which were essential for the transition from G1 to S phase, was inhibited. At the same time, heat stress inhibited the estradiol synthesis of GCs by decreasing CYP11A1 and CYP19A1 gene expression. A total of 241 DEGs including 181 upregulated and 60 downregulated ones were identified. Transcriptome result shows that heat shock protein and CXC chemokines gene were significantly activated during heat stress. While collagenases (MMP1 and MMP13) and strome lysins (MMP3) were downregulated. And, the hedgehog signaling pathway may be a prosurvival adaptive response under heat stress. These results offer a basis for better understanding the molecular mechanism underlying lay-eggs-less in ducks under heat stress.

Baicalin improves the in vitro developmental capacity of pig embryos by inhibiting apoptosis, regulating mitochondrial activity and activating sonic hedgehog signaling

Baicalin, a traditional Chinese medicinal monomer whose chemical structure is known, can be used to treat female infertility. However, the effect of baicalin on embryonic development is unknown. This study investigated the effects of baicalin on in vitro development of parthenogenetically activated (PA) and in vitro fertilized (IVF) pig embryos and the underlying mechanisms involved. Treatment with 0.1 μg/ml baicalin significantly improved (P < 0.05) the in vitro developmental capacity of PA pig embryos by reducing the reactive oxygen species (ROS) levels and apoptosis and increasing the mitochondrial membrane potential (ΔΨm) and ATP level. mRNA and protein expression of sonic hedgehog (SHH) and GLI1, which are related to the SHH signaling pathway, in PA pig embryos at the 2-cell stage, were significantly higher in the baicalin-treated group than in the control group. To confirm that the SHH signaling pathway is involved in the mechanism by which baicalin improves embryonic development, we treated embryos with baicalin in the absence or presence of cyclopamine (Cy), an inhibitor of this pathway. Cy abolished the effects of baicalin on in vitro embryonic development. In conclusion, baicalin improves the in vitro developmental capacity of PA and IVF pig embryos by inhibiting ROS production and apoptosis, regulating mitochondrial activity and activating SHH signaling.

Investigating the role of BCAR4 in ovarian physiology and female fertility by genome editing in rabbit

Breast Cancer Anti-estrogen Resistance 4 (BCAR4) was previously characterised in bovine species as a gene preferentially expressed in oocytes, whose inhibition is detrimental to in vitro embryo development. But its role in oogenesis, folliculogenesis and globally fertility in vivo remains unknown. Because the gene is not conserved in mice, rabbits were chosen for investigation of BCAR4 expression and function in vivo. BCAR4 displayed preferential expression in the ovary compared to somatic organs, and within the ovarian follicle in the oocyte compared to somatic cells. The transcript was detected in follicles as early as the preantral stage. Abundance decreased throughout embryo development until the blastocyst stage. A lineage of genome-edited rabbits was produced; BCAR4 expression was abolished in follicles from homozygous animals. Females of wild-type, heterozygous and homozygous genotypes were examined for ovarian physiology and reproductive parameters. Follicle growth and the number of ovulations in response to hormonal stimulation were not significantly different between genotypes. Following insemination, homozygous females displayed a significantly lower delivery rate than their heterozygous counterparts (22 ± 7% vs 71 ± 11% (mean ± SEM)), while prolificacy was 1.8 ± 0.7 vs 6.0 ± 1.4 kittens per insemination. In conclusion, BCAR4 is not essential for follicular growth and ovulation but it contributes to optimal fertility in rabbits.

In vitro oocyte maturation in a medium containing reduced sodium chloride improves the developmental competence of pig oocytes after parthenogenesis and somatic cell nuclear transfer

The present study investigated the effects of IVM in hypotonic medium containing reduced (61.6mM) NaCl compared with isotonic medium containing 108.0mM NaCl (designated L and N respectively) on oocyte maturation and embryonic development in pigs. IVM culture was divided into four periods at 11-h intervals. Oocytes cultured in N for 33h and then in L for 11h of IVM (N-N-N-L) showed significantly improved (P<0.05) nuclear maturation of oocytes (75.4-79.0% vs 60.2-85.8%) and blastocyst formation (61.5-66.1% vs 45.2-67.5%) after parthenogenesis (PA) compared with other treatments (L-L-L-L, L-L-L-N, L-L-N-L, N-N-L-L, N-N-L-N, L-L-N-L, L-N-N-L and N-L-N-L). Oocytes matured in L-L-L-L and N-N-N-L had an increased (P<0.05) perivitelline space (11.0-12.5 vs 5.5µm) and intraoocyte reduced glutathione (GSH) content (1.39-1.41 vs 1.00 pixels per oocyte) relative to oocytes matured in N-N-N-N. Somatic cell nuclear transfer (SCNT) embryos derived from the N-N-N-L treatment had significantly (P<0.05) higher blastocyst formation (53.5%) than embryos derived from Medium-199 (37.4%) and N-N-N-N (41.8%) treatments. Overall, the results demonstrate that maturation of pig oocytes in hypotonic medium with reduced NaCl during the last 11h of IVM increases the developmental competence of oocytes after PA and SCNT by improving the cytoplasmic microenvironment, including an increased GSH content in IVM oocytes.

Sonic hedgehog signaling mediates resveratrol to improve maturation of pig oocytes in vitro and subsequent preimplantation embryo development

The beneficial effects of resveratrol on in vitro maturation (IVM) have been explained mainly by indirect antioxidant effects and limited information is available on the underlying mechanism by which resveratrol acts directly on porcine cumulus oocyte complexes (COCs). Recently, several studies reported that sonic hedgehog (SHH) signaling mediates resveratrol to exert its biological activities. Furthermore, SHH is an important signaling molecule for follicle development, oocyte maturation, and embryo development. Therefore, to elucidate the relationship between resveratrol and SHH signaling, we designed three groups: (i) control; (ii) resveratrol; and (iii) resveratrol with cyclopamine (SHH signaling inhibitor). We evaluated the effects of these agents on cumulus expansion, oocyte maturation, embryo development after parthenogenetic activation, expression levels of mRNAs in cumulus cells, oocytes and blastocysts, and protein expression in COCs. Resveratrol significantly increased the proportion of COCs exhibiting complete cumulus expansion (degree 4), oocyte nuclear maturation, cleavage and blastocyst formation rates and total cell numbers, which were blocked in the presence of cyclopamine. At the same time, a significant increase in the expression levels of mRNAs related to cumulus expansion, oocyte maturation and SHH signaling-related mRNAs and proteins from the resveratrol treatment group was also inhibited by simultaneous addition of cyclopamine. In conclusion, our results indicate that SHH signaling mediates resveratrol to improve porcine cumulus expansion, oocyte maturation, and subsequent embryo development.

Delayed blastocyst formation or an extra day culture increases apoptosis in pig blastocysts

In the present study, the timing was examined of blastocyst collection/formation or of how the duration of post-blastulation culture affected the quality and developmental competence of in vitro-produced pig parthenogenetic embryos. The earliest apoptotic signals were observed at the morula stage while the earliest cytoplasmic fragmentation was observed before the 4- to 8-cell stage of embryo development. Nuclear condensation was detected in morulae and blastocysts, but not all condensed nuclei were positive for the apoptotic signal (TUNEL staining). The mean blastocyst diameter increased with delayed blastocyst collection or extended post-blastulation culture, but decreased with delayed blastocyst formation. Delayed blastocyst collection/formation or an additional day of post-blastulation culture increased the frequencies of apoptosis, condensed nuclei, and low quality blastocysts (those showing a nuclear destruction that negated counting of the nuclei); increased the expression of the pro-apoptotic BAX gene; and reduced the ratio of ICM (inner cell mass) cells to TE (trophectoderm) cells. In addition, delayed blastocyst formation decreased POU5F1 gene expression. These results suggest that a delay in blastocyst collection/formation or an additional day of culture could increase the incidence of apoptosis, decrease the ICM:TE cell ratio, and influence the gene expression and diameter of blastocysts derived from in vitro-produced pig embryos. These findings provide a useful reference for improving the quality of in vitro-produced embryos.

Effect of purmorphamine on the mRNA expression of Sonic Hedgehog signaling downstream molecules in ovine embryo

Abstract. Sonic Hedgehog (SHH) is a signaling pathway mediated through a receptor system which seems to have effects on oocyte maturation and embryonic development. Purmorphamine is an SHH agonist that performs a crucial role in the regulation of the activity of SHH receptors and downstream transcription factors. The aim of this study was to analyze the effect of purmorphamine on the mRNA expression of SHH signaling downstream molecules (Patched1, Glioma-Associated Oncogene1, Smoothened, Histone Deacetylase1, Histone Deacetylase2 and Histone Deacetylase3) in ovine two-cell embryo. Ovaries were obtained from a slaughterhouse, and cumulus–oocyte complexes were aspirated and cultured in maturation media containing 0, 250 or 500 ng mL−1 purmorphamine. Then, oocytes were fertilized and cultured in a CR1 culture medium and after 24 h, two-cell embryos were collected for RNA extraction. Gene expression was evaluated by real-time polymerase chain reaction (PCR). Results indicated that in 250 ng mL−1 purmorphamine, Smo, Ptch1 and Hdac3 expression reduced, Hdac1 expression increased, and Gli1 and Hdac2 expression levels did not change. In 500 ng mL−1 purmorphamine, Gli1 and Smo transcripts increased, while Ptch1, Hdac2 and Hdac3 transcripts decreased. Regarding to the presence of SHH signaling molecules in two-cell embryos and their response to purmorphamine, it can be suggested that SHH signaling is probably active before embryonic genome activation in ovine embryos.

Production of viable cloned miniature pigs by aggregation of handmade cloned embryos at the 4-cell stage

The aim of the present study was to improve the quality of handmade cloned porcine embryos by multiple embryo aggregations. Embryos derived from aggregation of three cloned embryos (3×) had a better blastocyst rate than cloned control (1×) embryos (73.6% vs 35.1%, respectively; P<0.05), but did not differ from those produced by aggregation of two cloned embryos (2×; 63.0%). Total cell numbers differed among treatments (P<0.05), with the greatest cell numbers (126) in the 3× group and the lowest (55) in the control group. The ratio of inner cell mass:total cell number was comparable in the 2× and 3× groups (25.1% vs 26.1%, respectively) and was significantly better than that in the control group (15.3%). The proportion of apoptotic cells in 2× and 3× groups was lower than that in the control group (2.7% and 2.2% vs 4.7%, respectively; P<0.05). Expression of Oct4 and Cdx2 was higher, whereas that of Bax was lower (P<0.05), in the 3× compared with non-aggregate group. Seven piglets were born to two surrogate mothers after embryo transfer of 3× aggregated blastocysts. In conclusion, aggregated embryos had greater total cell numbers and better pluripotency gene expression, with reduced expression of the pro-apoptosis gene Bax. Collectively, these improvement may be associated with the development of cloned embryos to term.

Vascular endothelial growth factor A improves quality of matured porcine oocytes and developing parthenotes

Vascular endothelial growth factor is a multipotent angiogenic factor implicated in cell survival and proliferation. The objective was to determine effects of exogenous recombinant human VEGFA (or VEGFA165) in culture media on porcine oocyte maturation and parthenote development. Adding 5 ng/mL VEGFA to the culture medium improved the maturation rate of denuded oocytes (P < 0.05), although 5, 50, or 500 ng/mL did not significantly affect nuclear maturation of oocytes. Parthenotes from oocytes cultured either in in vitro maturation or in vitro culture medium supplemented with 5 or 50 ng/mL VEGFA had an improved blastocyst rate and increased total numbers of cells (P < 0.05). Moreover, those treated with 5 ng/mL of VEGFA had a higher hatched blastocyst rate (average of 121 cells per blastocyst). All VEGFA-treated oocytes had reduced apoptotic indices (P < 0.05), except for those with a higher dose (500 ng/mL) of VEGFA which had more apoptotic cells (P < 0.05). Adding 5 ng/mL VEGFA to oocytes during the last 22 h of in vitro maturation improved (P < 0.05) blastocyst rates and total numbers of cells, with reduced apoptosis indices similar to that of long-term (44 h) culture. Furthermore, Axitinib (VEGFR inhibitor) reversed the effects of VEGFA on parthenote development (P < 0.05). Follicular fluids from medium (2-6 mm) to large (>6 mm) follicles contained 5.3 and 7.0 ng/mL vascular endothelial growth factor protein, respectively, higher (P < 0.05) than concentrations in small (<2 mm) follicles (0.4 ng/mL). Also, VEGFA and its receptor (VEGFR-2) were detected (immunohistochemistry) in growing follicles and developing blastocysts. In addition, VEGFA inhibited caspase-3 activation in matured oocytes (P < 0.05). In conclusion, this is apparently the first report that VEGFA has proliferative and cytoprotective roles in maturing porcine oocytes and parthenotes. Furthermore, an optimal VEGFA concentration promoted porcine oocyte maturation and subsequent development.

Cyclopamine did not affect mouse oocyte maturation in vitro but decreased early embryonic development

Hedgehog (Hh) pathway has been studied in various animal body life procedures and is suggested to be important for the development of multiple organs. The genes involved in the Hh signaling pathway were expressed in the ovary of mice, pigs and cattle. However, the function of Hh signaling pathway on oocyte maturation and early embryonic development is still controversial. We detected the effect of sonic hedgehog (Shh) and cyclopamine on the in vitro maturation of mouse oocytes and embryo development. The results showed that the presence of Shh or cyclopamine resulted in similar oocyte maturation to control groups. Shh did not improve early embryonic development. However, the supplement of cyclopamine depressed early embryo development. The mRNA of shh, ptch1, smo and gli1 were less detected in the denuded oocytes. The expression levels of ptch1 ascended from the uncleaved zygote to blastocyst stage. Smo or gli1 were expressed on a higher level at the two-cell or four-cell stage in early embryonic development separately. Therefore, Shh did not affect mouse oocyte maturation and early embryo development, but cyclopamine led to inhibited development of mouse early embryo. The effects of Hh signaling on the oocyte maturation and early embryo development might be species-specific.

Early development of the porcine embryo: the importance of cell signalling in development of pluripotent cell lines

Understanding the cell signalling events that govern cell renewal in porcine pluripotent cells may help improve culture conditions and allow for establishment of bona fide porcine embryonic stem cells (pESC) and stable porcine induced pluripotent stem cells (piPSC). This review investigates cell signalling in the porcine preimplantation embryo containing either the inner cell mass or epiblast, with particular emphasis on fibroblast growth factor, SMAD, WNT and Janus tyrosine kinases/signal transducers and activators of transcription signalling. It is clear that key differences exist in the cell signalling events that govern pluripotency in this species compared with similar embryonic stages in mouse and human. The fact that bona fide pESC have still not been produced and that piPSC cannot survive in culture following the silencing or downregulation of the reprogramming transgenes suggest that culture conditions are not optimal. Unravelling the factor/s that regulate pluripotency in porcine embryos will pave the way for future establishment of stable pluripotent stem cell lines.

Ascorbic acid improves the developmental competence of porcine oocytes after parthenogenetic activation and somatic cell nuclear transplantation

In this study, a dose-response assessment was performed to understand the relation between supplementation of media with L-ascorbic acid or vitamin C and porcine oocyte maturation and the in vitro development of parthenotes (PA) and handmade cloned (HMC) embryos. Various concentrations (0, 25, 50 and 100 µg/ml) of vitamin C supplemented in in vitro maturation (IVM) and culture (IVC) media were tested. None of these vitamin C additions affected nuclear maturation of oocytes, yet supplementation at 50 µg/ml led to significantly increased intracellular glutathione (GSH) levels and reduced reactive oxygen species (ROS). When cultured in IVM- and/or IVC-supplemented media, the group supplemented with 50 µg/ml of vitamin C showed improved cleavage rates, blastocyst rates and total cell numbers per blastocyst (P<0.05) compared with other groups (control, 25 µg/ml and 100 µg/ml). In contrast, supplementation with 50 µg/ml vitamin C decreased (P<0.05) the apoptosis index as compared with the groups supplemented with 100 µg/ml. In addition, even with a lower blastocyst rate to start with (37.6 vs. 50.3%, P<0.05), supplementation of HMC embryos with vitamin C ameliorated their blastocyst quality to the extent of PA embryos as indicated by their total cell numbers (61.2 vs. 59.1). Taken together, an optimized concentration of vitamin C supplementation in the medium not only improves blastocyst rates and total cell numbers but also reduces apoptotic indices, whereas overdosages compromise various aspects of the development of parthenotes and cloned porcine embryos.

Developmental expression of lineage specific genes in porcine embryos of different origins

PURPOSE

This study compared the expression of genes involved in pluripotency, segregation of inner cell mass (ICM) and trophectoderm (TE), and primitive endoderm (PE) formation in porcine embryos produced by in vitro fertilization (IVF), parthenogenetic activation (PA), and nuclear transfer (NT) using either fetal fibroblasts (FF-NT) or mesenchymal stem cells (MSC-NT).

METHODS

Blastocyst formation and total cell number were analyzed. The expression patterns of transcripts, including SRY-related HMG-box gene 2 (SOX2), reduced expression gene 1 (REX1/ZFP42), LIN28, caudal type homeobox 2 (CDX2), TEA domain family member 4 (TEAD4), integrin beta 1 (ITGB1) and GATA6 were assessed at the 4-8 cell and blastocyst stage embryos by real-time PCR.

RESULTS

Developmental rates to blastocyst stage and total cell number were higher in IVF and PA embryos than in NT embryos. But MSC-NT embryos had increased blastocyst formation and higher total cell number compared to FF-NT embryos. The relative expressions of transcripts were higher in blastocysts than in 4-8 cell stage embryos. The mRNA expression levels of SOX2 and REX1 were largely similar in embryos of different origins. However, the genes such as LIN28, CDX2, TEAD4, ITGB1 and GATA6 showed the differential expression pattern in PA and NT embryos compared to IVF embryos. Importantly, the transcript levels in MSC-NT embryos were relatively less variable to IVF than those in FF-NT embryos.

CONCLUSION

MSCs seem to be better donors for porcine NT as they improved the developmental competency, and influenced the expression pattern of genes quite similar with IVF embryos than that of FFs.

Advances on in vitro production and cryopreservation of porcine embryos

There have been intensive attempts to establish reliable in vitro production (IVP) and cryopreservation methods of embryos in pigs. Although a great deal of progress has been made, current IVP systems and cryopreservation still suffer from insufficient cytoplasmic abilities of in vitro matured oocytes, polyspermic fertilization, poor quality of in vitro produced embryos and low efficiency of embryo cryopreservation. Compared to other mammalian species, pig oocytes and embryos are characterized by large amounts of lipid content stored mainly in the form of lipid droplets in the cytoplasm. This fact has a negative influence on biotechnological applications on porcine oocytes and embryos. In this review, we will discuss recent studies about methods and techniques for modifying porcine embryo IVP system and embryo cryopreservation that produces high quality of pig blastocysts using in vitro maturation, in vitro fertilization, in vitro culture, microsurgical manipulation, addition of protein, the use of cytoskeleton stabilizing agents and various physical methods. The presented methods and techniques make it possible to modify the characteristics of oocytes and embryos and thus may become major tools in mammalian gamete and embryo agricultural or biotechnological applications in the future.