Reproductive technologies and the porcine embryonic transcriptome

Enhancing antioxidant levels and mitochondrial function in porcine oocyte maturation and embryonic development through notoginsenoside R1 supplementation

This study examines the impact of Notoginsenoside R1 (NGR1), a compound from Panax notoginseng, on the maturation of porcine oocytes and their embryonic development, focusing on its effects on antioxidant levels and mitochondrial function. This study demonstrates that supplementing in vitro maturation (IVM) medium with NGR1 significantly enhances several biochemical parameters. These include elevated levels of glutathione (GSH), nuclear factor erythrocyte 2-related factor 2 (NRF2) and mRNA expression of catalase (CAT) and GPX. Concurrently, we observed a decrease in reactive oxygen species (ROS) levels and an increase in JC-1 immunofluorescence, mitochondrial distribution, peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α) and nuclear NRF2 mRNA levels. Additionally, there was an increase in ATP production and lipid droplets (LDs) immunofluorescence. These biochemical improvements correlate with enhanced embryonic outcomes, including a higher blastocyst rate, increased total cell count, enhanced proliferative capacity and elevated octamer-binding transcription factor 4 (Oct4) and superoxide dismutase 2 (Sod2) gene expression. Furthermore, NGR1 supplementation resulted in decreased apoptosis, reduced caspase 3 (Cas3) and BCL2-Associated X (Bax) mRNA levels and decreased glucose-regulated protein 78 kD (GRP78) immunofluorescence in porcine oocytes undergoing in vitro maturation. These findings suggest that NGR1 plays a crucial role in promoting porcine oocyte maturation and subsequent embryonic development by providing antioxidant levels and mitochondrial protection.

Supplementation with Niacin during in vitro maturation improves the quality of porcine embryos

Niacin, also known as vitamin B3, has a pivotal role in energy metabolism, cellular signaling cascades regulating gene expression, and apoptosis. However, the effect of Niacin on porcine early embryo developmental competence remains to be elucidated. The present study aimed to assess the effects of Niacin treatment during in vitro maturation (IVM) on the nuclear maturation of porcine oocytes and subsequent development of in vitro embryos. In addition, the expression profiles of selected genes related to lipid metabolism, oxidative stress, and apoptosis were assessed. The IVM medium was supplemented with different concentrations of Niacin (0, 300, 600, and 900 μM). The results showed that a high concentration of Niacin (900 μM) significantly decreased cumulus expansion compared to the other groups (p < 0.05). No significant difference was observed among the experimental groups for nuclear maturation rate. Niacin treatments (300, 600, and 900 μM) during IVM significantly (p < 0.05) enhanced glutathione levels. Treatment with 300 and 600 μM significantly (p < 0.05) lowered the reactive oxygen species levels compared to treatment with 900 μM and the control group. Niacin supplementation to the IVM media significantly improved the cleavage and blastocyst rates compared to the control group. Supplementation with 300 and 600 μM of Niacin significantly increased the total cell number of blastocysts compared to supplementation with 900 μM or the control groups. Cytoplasmic lipid droplets were significantly reduced after 600 μM treatment. Supplementation of Niacin to IVM media positively affected the relative expression of genes related to energy and oxidative status (SIRT1), pro-apoptosis (BAX), anti-apoptosis (BCL2), and lipid metabolism (ACACA and PNPLA2) in cumulus cells and oocytes. Taken together, Niacin supplementation to porcine IVM media improved the developmental competence of early embryos mainly through protection against oxidative stress and its influence on energy metabolism and apoptosis pathways.

Assessment of the Growth and Reproductive Performance of Cloned Pietrain Boars

How to maximize the use of the genetic merits of the high-ranking boars (also called superior ones) is a considerable question in the pig breeding industry, considering the money and time spent on selection. Somatic cell nuclear transfer (SCNT) is one of the potential ways to answer the question, which can be applied to produce clones with genetic resources of superior boar for the production of commercial pigs. For practical application, it is essential to investigate whether the clones and their progeny keep behaving better than the "normal boars", considering that in vitro culture and transfer manipulation would cause a series of harmful effects to the development of clones. In this study, 59,061 cloned embryos were transferred into 250 recipient sows to produce the clones of superior Pietrain boars. The growth performance of 12 clones and 36 non-clones and the semen quality of 19 clones and 28 non-clones were compared. The reproductive performance of 21 clones and 25 non-clones were also tested. Furthermore, we made a comparison in the growth performance between 466 progeny of the clones and 822 progeny of the non-clones. Our results showed that no significant difference in semen quality and reproductive performance was observed between the clones and the non-clones, although the clones grew slower and exhibited smaller body size than the non-clones. The F1 progeny of the clones showed a greater growth rate than the non-clones. Our results demonstrated through the large animal population showed that SCNT manipulation resulted in a low growth rate and small body size, but the clones could normally produce F1 progeny with excellent growth traits to bring more economic benefits. Therefore, SCNT could be effective in enlarging the merit genetics of the superior boars and increasing the economic benefits in pig reproduction and breeding.

Contributions of RNA-seq to improve in vitro embryo production (IVP)

In Vitro Embryo Production (IVP) is widely used to improve the reproductive efficiency of livestock animals, however increasing the embryo development rates and pregnancy outcomes is still a challenge for some species. Thus, the lack of biological knowledge hinders developing specie-specific IVP protocols. Therefore, the contributions of RNA-seq to generate relevant biological knowledge and improve the efficiency of IVP in livestock animals are reviewed herein.

Applications of omics and nanotechnology to improve pig embryo production in vitro

An appropriate environment to optimize porcine preimplantation embryo production in vitro is required as genetically modified pigs have become indispensable for biomedical research and agriculture. To provide suitable culture conditions, omics technologies have been applied to elucidate which metabolic substrates and pathways are involved during early developmental processes. Metabolomic profiling and transcriptional analysis comparing in vivo- and in vitro-derived embryos have demonstrated the important role of amino acids during preimplantation development. Transcriptional profiling studies have been helpful in assessing epigenetic reprogramming agents to allow for the correction of gene expression during the cloning process. Along with this, nanotechnology, which is a highly promising field, has allowed for the use of engineered nanoplatforms in reproductive biology. A growing number of studies have explored the use of nanoengineered materials for sorting, labeling, and targeting purposes; which demonstrates their potential to become one of the solutions for precise delivery of molecules into gametes and embryos. Considering the contributions of omics and the recent progress in nanoscience, in this review, we focused on their emerging applications for current in vitro pig embryo production systems to optimize the generation of genetically modified animals.

Bioinformatics analysis of hepatitis C virus genotype 2a-induced human hepatocellular carcinoma in Huh7 cells

Hepatocellular carcinoma (HCC) is a liver cancer that could be induced by hepatitis C virus genotype 2a Japanese fulminant hepatitis-1 (JFH-1) strain. The aim of this study was to investigate the molecular mechanisms of HCC. The microarray data GSE20948 includes 14 JFH-1- and 14 mock (equal volume of medium [control])-infected Huh7 samples. The data were downloaded from the Gene Expression Omnibus. After data processing, soft cluster analyses were performed to identify co-regulated genes with similar temporal expression patterns. Functional and pathway enrichment analyses, as well as functional annotation analysis, were performed. Subsequently, combined networks of protein–protein interaction network, microRNA regulatory network, and transcriptional regulatory network were constructed. Hub nodes, modules, and five clusters of co-regulated genes were also identified. In total, 173 up and 207 down co-regulated genes were separately identified in JFH-1-infected Huh7 cells compared with those of control cells. Functional enrichment analysis indicated that up co-regulated genes were related to skeletal system morphogenesis and neuron differentiation and down co-regulated genes were related to steroid/cholesterol/sterol metabolisms. Hub genes (such as IRF1, GBP1, ICAM1, Foxa1, DHCR7, HMGCS2, and MSMO1) were identified. Transcription factors IRF1 and Foxa1 were the targets of miR-130a, miR-17-5p, and miR-20a. PPARGC1A was targeted by miR-29 family, and MSMO1 was the target of miR-23 family. Hub nodes (such as IRF1, GBP1, ICAM1, Foxa1, DHCR7, HMGCS2, and MSMO1) and microRNAs might be used as candidate biomarkers of JFH-1-infected HCC.

The Equine Embryo Influences Immune-Related Gene Expression in the Oviduct

Although the equine oviduct clearly affects early embryo development and the selective transport of equine embryos through the oviduct indicates a reciprocal interaction, the influence of the embryo on gene expression in the oviduct remains to be determined in the horse. The aim of this study was to examine this by means of RNA sequencing. Four days after ovulation, epithelial cells ipsilateral and contralateral to the ovulation side from five cyclic and five pregnant mares were collected from the oviduct. RNA was extracted, samples were sequenced, and data analysis was performed to determine differentially expressed genes (DEGs) (P value ≤0.05 and absolute fold change ≥2) and to provide functional interpretation. A total of 10 743 transcripts were identified and 253 genes were found to be upregulated and 108 to be downregulated in the pregnant ipsilateral oviduct when compared to the cyclic ipsilateral oviduct. Comparison of the ipsilateral and the contralateral oviduct indicated 164 DEGs in pregnant mares and 77 DEGs in cyclic mares. Enriched functional categories were detected only in the comparison of pregnant and cyclic ipsilateral oviducts and showed that the equine embryo affects the expression of immune response-related genes in the oviduct, with marked upregulation of interferon-associated genes. This research represents the foundation for further assessment of the role of specific genes in the early embryo-maternal dialogue of the horse.

Determinant molecular markers for peri-gastrulating bovine embryo development

Peri-gastrulation defines the time frame between blastocyst formation and implantation that also corresponds in cattle to elongation, pregnancy recognition and uterine secretion. Optimally, this developmental window prepares the conceptus for implantation, placenta formation and fetal development. However, this is a highly sensitive period, as evidenced by the incidence of embryo loss or early post-implantation mortality after AI, embryo transfer or somatic cell nuclear transfer. Elongation markers have often been used within this time frame to assess developmental defects or delays, originating either from the embryo, the uterus or the dam. Comparatively, gastrulation markers have not received great attention, although elongation and gastrulation are linked by reciprocal interactions at the molecular and cellular levels. To make this clearer, this peri-gastrulating period is described herein with a focus on its main developmental landmarks, and the resilience of the landmarks in the face of biotechnologies is questioned.