6 GENE EXPRESSION ANALYSIS OF IN VIVO- AND IN VITRO-MATURED PORCINE METAPHASE II OOCYTES

2014 ◽  
Vol 26 (1) ◽  
pp. 117 ◽  
Author(s):  
L. Cox ◽  
G. Saunders ◽  
J. Stevens ◽  
S. C. Isom

In vitro-matured (IVM) oocytes lack the same developmental competence as oocytes that are matured in vivo (IVV), yet no compelling explanation for this discrepancy has been provided at the molecular level. The aim of this study was to quantify and compare mRNA levels in IVM and IVV oocytes for genes from a wide variety of functional gene categories, including RNA degradation, pluripotency, epigenome modification, oocyte-specific, and apoptosis. Quantitative real-time PCR (qPCR) was used to evaluate the relative gene expression levels of 70 genes in each of 33 individual IVM oocytes from 4 different collection days and 29 individual IVV oocytes from 4 different donor animals. The qPCR data were analysed using ANOVA and significance was assigned at P < 0.05. After a multiple testing correction was applied, relative transcript abundances for 32 of the 70 genes tested were found to be significantly different (q < 0.05) between the IVM and IVV oocytes. Of these significantly different genes, 23 were higher in the IVM oocytes and only 9 were higher in the IVV oocytes. The 32 significantly differentially expressed genes were then evaluated in relation to their corresponding functional gene categories. Of particular interest, transcripts for 7/14 RNA degradation-related genes (CNOT3, DCP1A, DDX6, LSM1, PABPN1, PABPN1L, PARN) and 3/9 oocyte specific genes (BMP15, YBX2, H1FOO) were significantly more abundant in the IVM oocytes. In contrast, transcripts for 4/8 epigenetic related transcripts (ASH2l, DNMT1, EHMT2, EZH2), 2/2 apoptosis related genes (BCL2, XIAP), and 1/4 pluripotency factors (LIN28) were significantly more abundant in the IVV oocytes. Gene set enrichment analysis confirmed that, within the context of this experimental design, RNA degradation and chromatin remodelling pathways are significantly perturbed in IVM oocytes. We conclude that in vitro maturation has profound effects on transcript populations of metaphase-II oocytes, with most transcripts being higher in IVM oocytes. We expect that this data will lead to a better understanding of how we can improve the quality of oocytes that are matured in vitro as well as provide information to help to identify markers that could be indicative of oocyte quality.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kornphimol Kulthong ◽  
Guido J. E. J. Hooiveld ◽  
Loes Duivenvoorde ◽  
Ignacio Miro Estruch ◽  
Victor Marin ◽  
...  

AbstractGut-on-chip devices enable exposure of cells to a continuous flow of culture medium, inducing shear stresses and could thus better recapitulate the in vivo human intestinal environment in an in vitro epithelial model compared to static culture methods. We aimed to study if dynamic culture conditions affect the gene expression of Caco-2 cells cultured statically or dynamically in a gut-on-chip device and how these gene expression patterns compared to that of intestinal segments in vivo. For this we applied whole genome transcriptomics. Dynamic culture conditions led to a total of 5927 differentially expressed genes (3280 upregulated and 2647 downregulated genes) compared to static culture conditions. Gene set enrichment analysis revealed upregulated pathways associated with the immune system, signal transduction and cell growth and death, and downregulated pathways associated with drug metabolism, compound digestion and absorption under dynamic culture conditions. Comparison of the in vitro gene expression data with transcriptome profiles of human in vivo duodenum, jejunum, ileum and colon tissue samples showed similarities in gene expression profiles with intestinal segments. It is concluded that both the static and the dynamic gut-on-chip model are suitable to study human intestinal epithelial responses as an alternative for animal models.


2005 ◽  
Vol 17 (8) ◽  
pp. 751 ◽  
Author(s):  
Mona E. Pedersen ◽  
Øzen Banu Øzdas ◽  
Wenche Farstad ◽  
Aage Tverdal ◽  
Ingrid Olsaker

In this study the synthetic oviduct fluid (SOF) system with bovine oviduct epithelial cell (BOEC) co-culture is compared with an SOF system with common protein supplements. One thousand six hundred bovine embryos were cultured in SOF media supplemented with BOEC, fetal calf serum (FCS) and bovine serum albumin (BSA). Eight different culture groups were assigned according to the different supplementation factors. Developmental competence and the expression levels of five genes, namely glucose transporter-1 (Glut-1), heat shock protein 70 (HSP), connexin43 (Cx43), β-actin (ACTB) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), analysed as mRNA by using reverse transcription–polymerase chain reaction, were measured on bovine embryos cultured for 9 days. Gene expression of these in vitro-produced embryos was compared with the gene expression of in vivo-produced embryos. There was no significant difference found in embryo developmental competence between the Day 9 embryos in BOEC co-culture, FCS and BSA supplements in SOF media. However, differences in gene expression were observed. With respect to gene expression in in vivo and in vitro embryos, BOEC co-culture affected the same genes as did supplementation with FCS and BSA. HSP was the only gene that differed significantly between in vitro and in vivo embryos. When the different in vitro groups were compared, a significant difference between the BOEC co-culture and the FCS supplementation groups due to Glut-1 expression was observed.


2017 ◽  
Vol 29 (9) ◽  
pp. 1667 ◽  
Author(s):  
M. Arias-Álvarez ◽  
R. M. García-García ◽  
J. López-Tello ◽  
P. G. Rebollar ◽  
A. Gutiérrez-Adán ◽  
...  

In vivo-matured cumulus–oocyte complexes are valuable models in which to assess potential biomarkers of rabbit oocyte quality that contribute to enhanced IVM systems. In the present study we compared some gene markers of oocytes and cumulus cells (CCs) from immature, in vivo-matured and IVM oocytes. Moreover, apoptosis in CCs, nuclear maturation, mitochondrial reallocation and the developmental potential of oocytes after IVF were assessed. In relation to cumulus expansion, gene expression of gap junction protein, alpha 1, 43 kDa (Gja1) and prostaglandin-endoperoxide synthase 2 (Ptgs2) was significantly lower in CCs after in vivo maturation than IVM. In addition, there were differences in gene expression after in vivo maturation versus IVM in both oocytes and CCs for genes related to cell cycle regulation and apoptosis (V-Akt murine thymoma viral oncogene homologue 1 (Akt1), tumour protein 53 (Tp53), caspase 3, apoptosis-related cysteine protease (Casp3)), oxidative response (superoxide dismutase 2, mitochondrial (Sod2)) and metabolism (glucose-6-phosphate dehydrogenase (G6pd), glyceraldehyde-3-phosphate dehydrogenase (Gapdh)). In vivo-matured CCs had a lower apoptosis rate than IVM and immature CCs. Meiotic progression, mitochondrial migration to the periphery and developmental competence were higher for in vivo-matured than IVM oocytes. In conclusion, differences in oocyte developmental capacity after IVM or in vivo maturation are accompanied by significant changes in transcript abundance in oocytes and their surrounding CCs, meiotic rate, mitochondrial distribution and apoptotic index. Some of the genes investigated, such as Gja1, could be potential biomarkers for oocyte developmental competence in the rabbit model, helping improve in vitro culture systems in these species.


2008 ◽  
Vol 20 (1) ◽  
pp. 82
Author(s):  
M. Paczkowski ◽  
C. Bidwell ◽  
D. Spurlock ◽  
J. Waddell ◽  
R. L. Krisher

The in vitro culture environment significantly impacts nuclear maturation, fertilization, embryonic development, and epigenetic competence; however, our knowledge of the effects of in vitro maturation on oocyte developmental competence, and specifically cytoplasmic maturation, is limited. The objective of this experiment was to identify alterations in the transcriptome of oocytes matured in vitro compared to those matured in vivo that correlate to developmental competence. Immature oocytes were collected from Day 26 and 7-8-week-old B6D2F1 mice 48 h post-pregnant mare serum gonadotropin (PMSG) administration and matured for 16 h in Gmat supplemented with 0.5 mm citric acid, 0.5 mm cysteamine, 100 ng mL–1 epidermal growth factor (EGF), 0.05% insulin-transferrin-selenium (ITS; v/v), 0.01% recombumin (v/v) and 2 mg mL–1 fetuin. In vivo-matured oocytes from females of the same ages were collected from the oviducts 62 h post-PMSG and 14 h post-hCG and mating to vasectomized males. In vivo- and in vitro-matured oocytes were identified visually by the presence of the first polar body. Mature oocytes were pooled into three groups of 150 oocytes per treatment and lysed; poly A+ RNA was extracted. Samples were processed through two cycles of linear amplification and hybridized to the GeneChip� Mouse Genome 430 2.0 Array (Affymetrix, Inc., Santa Clara, CA, USA), with three arrays per treatment. Microarray data were sorted and filtered to include genes that were classified as having two present calls per treatment. The data were then normalized to the chip median and analyzed using a one-way analysis of variance; the level of significance was calculated at P < 0.01. In total, 2.17% (482/22170) and 1.61% (358/22170) of genes were differentially expressed between in vitro- and in vivo-matured oocytes in Day 26 and 7–8-week-old mice, respectively. However, 72.82% (351/482) and 67.87% (243/358) of differentially expressed genes had increased abundance in the in vitro- and in vivo-matured oocytes, respectively. Transcripts involved in gene expression, cellular growth and proliferation, and cellular development were increased in in vivo-matured oocytes from both age groups compared to those matured in vitro. Cell death was one of the higher ranking functional groups increased in the 7–8-week-old in vitro-matured oocytes compared to the 7–8-week-old in vivo-matured oocytes. Specific genes altered by in vitro maturation conditions in Day 26 oocytes were DNA methyltransferase 1 (>7-fold increase in vivo), caspase 8 (>4-fold increase in vivo), and eukaryotic translation initiation factor 1B (>4-fold increase in vivo). DNA methyltransferase 1 and ubiquitin-conjugating enzyme E2T were significantly increased in in vivo-matured 7–8-week-old oocytes (>3-fold and >5-fold, respectively). These results indicate that gene expression is altered in oocytes matured in vitro compared to those matured in vivo. Based on the functional annotations of genes differentially expressed, dysregulation of gene expression in the oocyte resulting in altered DNA methylation and an up-regulation in cell death pathways are potential developmental mechanisms influenced by in vitro culture conditions that correlate to reduced embryonic developmental potential.


2018 ◽  
Author(s):  
Nikita Mukhitov ◽  
Michael G. Roper

AbstractIn vivo levels of insulin are oscillatory with a period of ~5-10 minutes, implying that the numerous islets of Langerhans within the pancreas are synchronized. While the synchronizing factors are still under investigation, one result of this behavior is expected to be coordinated intracellular [Ca2+] ([Ca2+]i) oscillations throughout the islet population. The role that coordinated [Ca2+]i oscillations have on controlling gene expression within pancreatic islets was examined by comparing gene expression levels in islets that were synchronized using a low amplitude glucose wave and an unsynchronized population. The [Ca2+]i oscillations in the synchronized population were homogeneous and had a significantly lower drift in their oscillation period as compared to unsynchronized islets. This reduced drift in the synchronized population was verified by comparing the drift of in vivo and in vitro profiles from published reports. Microarray profiling indicated a number of Ca2+-dependent genes were differentially regulated between the two islet populations. Gene set enrichment analysis revealed that the synchronized population had reduced expression of gene sets related to protein translation, protein turnover, energy expenditure, and insulin synthesis, while those that were related to maintenance of cell morphology were increased. It is speculated that these gene expression patterns in the synchronized islets results in a more efficient utilization of intra-cellular resources and response to environmental changes.


2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Françoise I. Bussière ◽  
Valérie Michel ◽  
Julien Fernandes ◽  
Lionel Costa ◽  
Vania Camilo ◽  
...  

Helicobacter pylori infection causes chronic gastritis and is the major risk factor of gastric cancer. H. pylori induces a chronic inflammation-producing reactive oxygen species (ROS) which is a source of chromosome instabilities and contributes to the development of malignancy. H. pylori also promotes DNA hypermethylation, known to dysregulate essential genes that maintain genetic stability. The maintenance of telomere length by telomerase is essential for chromosome integrity. Telomerase reverse transcriptase (TERT) is the catalytic component of telomerase activity and an important target during host-pathogen interaction. We aimed to investigate the consequences of H. pylori on the regulation of TERT gene expression and telomerase activity. In vitro, hTERT mRNA levels and telomerase activity were analysed in H. pylori-infected human gastric epithelial cells. In addition, C57BL/6 and INS-GAS mice were used to investigate the influence of H. pylori-induced inflammation on TERT levels. Our data demonstrated that, in vitro, H. pylori inhibits TERT gene expression and decreases the telomerase activity. The exposure of cells to lycopene, an antioxidant compound, restores TERT levels in infected cells, indicating that ROS are implicated in this downregulation. In vivo, fewer TERT-positive cells are observed in gastric tissues of infected mice compared to uninfected, more predominantly in the vicinity of large aggregates of lymphocytes, suggesting an inflammation-mediated regulation. Furthermore, H. pylori appears to downregulate TERT gene expression through DNA hypermethylation as shown by the restoration of TERT transcript levels in cells treated with 5′-azacytidine, an inhibitor of DNA methylation. This was confirmed in infected mice, by PCR-methylation assay of the TERT gene promoter. Our data unraveled a novel way for H. pylori to promote genome instabilities through the inhibition of TERT levels and telomerase activity. This mechanism could play an important role in the early steps of gastric carcinogenesis.


1998 ◽  
Vol 20 (2) ◽  
pp. 261-270 ◽  
Author(s):  
T Engstrom ◽  
P Bratholm ◽  
H Vilhardt ◽  
NJ Christensen

The nona-peptide oxytocin (OT) induces contraction of the myometrium by interaction with specific plasma membrane associated OT receptors (OTR), whereas stimulation of beta2-adrenoceptors (beta2AR) causes relaxation. Homologous desensitization of the myometrium to both hormones has been described. However, a possible interaction between the two systems has not been investigated. In the present study, long-term in vivo treatment of non-pregnant estrogen-primed rats with isoproterenol decreased maximal relaxation of isolated uterine strips challenged with isoproterenol. Increased EC50 values of similarly treated animals suggest that the coupling between receptor occupancy and contractile response was impaired. Since beta2AR mRNA levels were left unchanged, we conclude that the homologous desensitization to beta2 stimulation is not due to changes in beta2AR gene expression. OT infusion did not alter beta2AR mRNA levels or isoproterenol-induced relaxation of isolated uterine strips. Treatment with OT had no effect on the amount of myometrial OTR mRNA. We have previously found that OT down-regulates OTR in the non-pregnant rat myometrium, but this therefore does not appear to take place at the level of mRNA production. Isoproterenol treatment resulted in a three-fold increase in OTR mRNA. This was accompanied by a 91% rise in OTR binding and an augmented contractile response of isolated uterine strips to OT, suggesting that the increased production of mRNA reflects formation of active receptors. Neither OTR affinity nor EC50 of in vitro strips was affected by isoproterenol treatment. We conclude that stimulation of beta2AR causes heterologous up-regulation of OTR in the non-pregnant estrogen-primed rat myometrium.


2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi47-vi47
Author(s):  
Alvaro Alvarado ◽  
Riki Kawaguchi ◽  
Giovanni Coppola ◽  
Steven Goldman ◽  
Harley Kornblum

Abstract Despite efforts to gain a deeper understanding of its molecular architecture, glioblastoma (GBM) remains uniformly fatal. While genome-based molecular subtyping has revealed that GBMs may be parsed into several distinct molecular categories, this insight has yielded little progress towards extending patient survival. In particular, the great phenotypic heterogeneity of GBM – both inter and intratumorally – has hindered therapeutic efforts. To this end, we interrogated tumor samples using a pathway-based approach to resolve tumoral heterogeneity. Gene set enrichment analysis (GSEA) was applied to gene expression data and used to provide an overview of each sample that was then compared to others, generating sample clusters based on overall patterns of enrichment. The Cancer Genome Atlas (TCGA) samples were clustered using canonical and oncogenic signatures and in both cases the clustering was distinct from the molecular subtypes previously reported. Using principal component analysis (PCA) and other bioinformatics tools, we extracted gene sets to further characterize the pathways contributing to each of these clusters. We generated gene lists of the top common elements and Ingenuity pathway analysis exposed molecular targets that control critical pathways of each identified cluster. Similar analyses were completed in a gene expression database of patient-derived gliomasphere lines and molecular targets were also obtained. We found E2F1 to be a strong target based on gene lists from both databases. A cluster of gliomasphere lines have high enrichment scores for the gene list predicted to depend on E2F1. In vitro genetic perturbation showed decrease stem cell frequency and lower expression of cell cycle progression genes in cell lines from this cluster exclusively. Other cluster-specific targets are being validated and in vivo studies will follow momentarily. Our studies relate intertumoral heterogeneity to critical cellular pathways dysregulated in GBM, with the ultimate goal of establishing a pipeline for patient- and tumor-specific precision medicine.


2012 ◽  
Vol 24 (1) ◽  
pp. 181
Author(s):  
T. Somfai ◽  
K. Imai ◽  
M. Kaneda ◽  
S. Akagi ◽  
S. Haraguchi ◽  
...  

A previous study revealed that follicle superstimulation significantly improved the developmental competence of immature bovine oocytes collected by ovum pickup (OPU; Imai et al. 2008 Reprod. Fertil. Dev. 20, 182). The aim of the present study was to investigate the effect of follicle superstimulation on the expression of developmentally important genes in bovine oocytes collected by OPU. Follicular oocytes were collected by OPU without (OPU group) or after follicle superstimulation by FSH (FSH/OPU group) by using a 7.5-MHz linear transducer with needle connected to an ultrasound scanner according to Imai et al. (2008). In the FSH/OPU group, after dominant follicle removal from Holstein dry cows by OPU, a CIDR was inserted on Day 5 (dominant follicle removal = Day 0). Cows then received 30 mg of FSH twice a day from Days 7 to 10 in decreasing doses (6, 6, 4, 4, 3, 3, 2, 2 mg) by IM injection. Cloprostenol (PGF; Clopromate C; Sumitomo Pharmaceuticals Co., Tokyo, Japan; 0.75 mg) was administered in the morning of Day 9 (third day of superstimulation). Oocyte collection by OPU was performed 48 h after PGF administration (Day 11) by the aspiration of follicles larger than 5 mm in diameter. In the OPU group, 3-to-6-mm follicles were aspirated without any previous hormone treatment. In vitro oocyte maturation (IVM) was performed according to Imai et al. (2006 J. Reprod. Dev. 52(Suppl), 19–29). Gene expression was assessed before (0 h IVM) and after IVM (22 h IVM) by RT quantitative PCR. The following genes were investigated: GAPDH, G6PDH, ACTB, H2A, CCNB1, MnSOD, OCT4, SOX2, CX43, HSP70, GLUT8, PAP, GDF9, COX1, ATP1A1, CDH1, CTNNB1, AQP3, DYNLL1, DYNC 1/1 and PMSB1. In brief, mRNA was extracted from 20 oocytes per sample using Qiagen RNeasy Micro kit (Qiagen, Valencia, CA, USA). Gene expression was analysed by a Roche Light Cycler 480 device. The relative expression of each gene was normalized to ACTB. Three replications were performed. Data were analysed by ANOVA. At 0 h IVM, PAP and DYNC 1/1 were found to be down-regulated (P < 0.05) in the FSH/OPU group compared with the OPU group, whereas the rest of the studied genes showed similar expression in the FSH/OPU and OPU groups. At 22 h IVM, PAP and DYNC 1/1 remained down-regulated in FSH/OPU oocytes. However, at this time the expression of GDF9 appeared significantly higher (P < 0.05) in FSH/OPU oocytes than in OPU oocytes. The expression of GDF9 was found to decrease during IVM in both groups; however, this decrease was less drastic in FSH/OPU oocytes. The results suggest that follicle superstimulation caused reduced expression of mRNA levels of PAP and DYNC 1/1 irrespective of maturation status and it also moderated the reduction of mRNA levels of GDF9 during IVM.


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