scholarly journals A comparative study of endoderm differentiation in humans and chimpanzees

2017 ◽  
Author(s):  
Lauren E. Blake ◽  
Samantha M. Thomas ◽  
John D. Blischak ◽  
Chiaowen Joyce Hsiao ◽  
Claudia Chavarria ◽  
...  

AbstractThere is substantial interest in the evolutionary forces that shaped the regulatory framework that is established in early human development. Progress in this area has been slow because it is difficult to obtain relevant biological samples. Inducible pluripotent stem cells (iPSCs) provide the ability to establish in vitro models of early human and non-human primate developmental stages. Using matched iPSC panels from humans and chimpanzees, we comparatively characterized gene regulatory changes through a four-day timecourse differentiation of iPSCs (day 0) into primary streak (day 1), endoderm progenitors (day 2), and definitive endoderm (day 3). As might be expected, we found that differentiation stage is the major driver of variation in gene expression levels, followed by species. We identified thousands of differentially expressed genes between humans and chimpanzees in each differentiation stage. Yet, when we considered gene-specific dynamic regulatory trajectories throughout the timecourse, we found that 75‥ of genes, including nearly all known endoderm developmental markers, have similar trajectories in the two species. Interestingly, we observed a marked reduction of both intra-and inter-species variation in gene expression levels in primitive streak samples compared to the iPSCs, with a recovery of regulatory variation in endoderm progenitors. The reduction of variation in gene expression levels at a specific developmental stage, paired with overall high degree of conservation of temporal gene regulation, is consistent with the dynamics of developmental canalization. Overall, we conclude that endoderm development in iPSC-based models are highly conserved and canalized between humans and our closest evolutionary relative.

2018 ◽  
Vol 110 ◽  
pp. 79-85 ◽  
Author(s):  
R. Laguna-Barraza ◽  
M.J. Sánchez-Calabuig ◽  
A. Gutiérrez-Adán ◽  
D. Rizos ◽  
S. Pérez-Cerezales

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Sabrina Borchert ◽  
Pia-Maria Suckrau ◽  
Robert F. H. Walter ◽  
Michael Wessolly ◽  
Elena Mairinger ◽  
...  

Abstract Malignant pleural mesothelioma (MPM) is a rare, but aggressive tumor with dismal prognosis. Platinum-based chemotherapy is regularly used as part of multimodality therapy. The expression of metallothioneins (MT) has been identified as a reason for cisplatin resistance, which often leads to early therapy failure or relapse. Thus, knockdown of MT expression may improve response to cisplatin treatment. The MT gene- and protein expression of the MPM-cell lines MSTO-211H, NCI-H2052 and NCI-H2452 and the human fibroblast cell line MRC-5, as well as their sensitivity to cisplatin treatment have been evaluated. Knockdown of MT1A, 1B and 2A expression was induced by RNA interference. MT expression was measured using quantitative real-time PCR. An in vitro Assay based on enzyme activity was used to detect cell viability, necrosis and apoptosis before and after incubation with cisplatin. MT2A gene expression could be detected in all MPM cell lines, showing the highest expression in NCI-H2452 and NCI-H2052, whereas gene expression levels of MT1A and MT1B were low or absent. The immunohistochemically protein expression of MT-I/II reflect MT2A gene expression levels. Especially for MSTO-211H cell presenting low initial MT2A levels, a strong induction of MT2A expression could be observed during cisplatin treatment, indicating a cell line-specific and platin-dependent adaption mechanism. Additionally, a MT2A-dependent cellular evasion of apoptosis during cisplatin could be observed, leading to three different MT based phenotypes. MSTO-211H cells showed lower apoptosis rates at an increased expression level of MT2A after cisplatin treatment (from sixfold to fourfold). NCI-H2052 cells showed no changes in MT2A expression, while apoptosis rate is the highest (8–12-fold). NCI-H2452 cells showed neither changes in alteration rate of MT2A expression nor changes in apoptosis rates, indicating an MT2A-independent resistance mechanism. Knockdown of MT2A expression levels resulted in significantly induced apoptotic rates during cisplatin treatment with strongest induction of apoptosis in each of the MPM cell lines, but in different markedness. A therapeutic meaningful effect of MT2A knockdown and subsequent cisplatin treatment could be observed in MSTO-211H cells. The present study showed MT2A to be part of the underlying mechanism of cisplatin resistance in MPM. Especially in MSTO-211H cells we could demonstrate major effects by knockdown of MT2A expression, verifying our hypothesis of an MT driven resistance mechanism. We could prove the inhibition of MT2A as a powerful tool to boost response rates to cisplatin-based therapy in vitro. These data carry the potential to enhance the clinical outcome and management of MPM in the future.


2006 ◽  
Vol 18 (2) ◽  
pp. 134
Author(s):  
S. Kurosaka ◽  
N. A. Leu ◽  
K. J. McLaughlin

Mammalian somatic cell clones frequently exhibit abnormal gene expression that presumably results from errors in reprogramming of the transplanted genome. In the mouse, aggregation of 4-cell stage clones with each other improves reprogramming with respect to Oct-4 expression in blastocysts and an increase in term development (Boiani et al. 2003 EMBO J. 22, 5304-5312). To determine if clone-clone aggregation has a similar beneficial effect in the bovine, we aggregated 8-16 cell bovine clones with each other and profiled gene expression levels in bovine clones and clone-clone aggregates at the blastocyst stage. Clone embryos were produced from fibroblasts and cultured in vitro in SOF supplemented with fetal bovine serum at 39�C in an atmosphere of 5% CO2, 5% O2, and 90% N2. For aggregation of embryos, we first removed the zonae pepellucidae by treatment with 0.5% pronase at the 8-16 cell stage and then placed two zona-free embryos per well into deep microwells produced on the bottom of a culture dish by pressing a heated darning needle onto the surface. Seven to 10 microwells in close proximity were covered by a culture 50-�L drop of culture medium, and embryos were cultured until Day 7. Real-time RT-PCR analysis for Oct-4, DNA methyltransferase 1 (Dnmt1), Dnmt3, glucose transporter 1 (Glut1), Glut3, and Poly(A) polymerase (PolyA) was performed on reusable Dynabead Oligo (dT)25-cDNA libraries synthesized from individual blastocysts at Day 7. In vitro-fertilized embryos were used as controls. To compare the variation of gene expression in each embryo within the group, the coefficient of variation (COV; standard deviation/mean) was calculated. Although spatial distribution of Oct-4 transcript is normal in bovine blastocyst stage clones (Kurosaka et al. 2004 Reprod. Fertil. Dev. 16, 147), we detected disturbances in the level of Oct-4 expression in clones: 44.4% (8 of 18) of clones expressed Oct-4 within a range of 0.5- and 1.5-fold of the average level of expression in IVF embryos, compared to 81.8% (9 of 11) of IVF embryos. Only 22.2% (4 of 18) of clones expressed all genes examined within a range of 0.5- and 2.0-fold of the average level of IVF embryos, versus 45.5% (5 of 11) of IVF embryos. Clone-clone aggregation did not increase the proportion of clones with normal expression levels but did reduce the coefficient of variation of gene expression levels between individual clones for the genes Oct-4, Dnmt1, Dnmt3a and PolyA, but not for Glut1 and Glut3. Interestingly, bovine clone-clone aggregates (n = 25) had less variation between individual embryos compared to IVF aggregates (n = 11) for all genes except Glut1 and Glut3, although variation of single clones was larger than that of single IVF embryos. Analysis of Oct-4 and �-Actin transcripts in mouse clone blastocysts indicated a similar decrease in gene expression variation subsequent to aggregation of mouse clones. These results demonstrate that bovine pre-implantation stage clones exhibit a high degree of variation in gene expression levels and suggest that aggregation of clones is beneficial in reducing the variation in expression of some genes.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
A Kocaman ◽  
B Ayas

Abstract Study question Does kisspeptin administration affect the motility parameters in sperm samples of subfertile cases? Summary answer Kisspeptin administration significantly increased gene expression levels related with sperm motility as well as intracellular calcium concentrations. What is known already Sperm motility problems are among the most important causes of male infertility. In recent years, a peptide named kisspeptin has been discovered that may have effects on sperm motility. Kisspeptin is known to trigger calcium release in hypothalamic neurons. In addition, kisspeptin administration increased sperm progressive motility in studies conducted on normozoospermic individuals. Furthermore, it is suggested that kisspeptin protein in seminal plasma is positively associated with semen quality. However, there is no evidence that how kisspeptin can affect sperm in men with infertility problems. Study design, size, duration This basic research study was an in vitro experimental approach involving the use of semen samples from an infertil cases between September to December in 2020. 40 men were included in both control and experimental groups. Participants/materials, setting, methods All analyses were performed on semen samples from 10 normozoospermic (NZ), 10 asthenozoospermic (AZ), 10 oligoasthenozoospermic (OAZ) and 10 oligoastenoteratozoospermic (OATZ) men, aging between (21-40) years. Basal serum and seminal kisspeptin levels were analyzed by ELISA. Sperm were divided into two groups. Kisspeptin-13 administered in vitro. KISS1, KISS1R, CATSPER1, AKAP4 gene expressions analyzed by qRT-PCR using 2−ΔΔCt algorithm. Intracellular calcium concentration was determined with floresence spectroflurometer and laser scanning confocal microscope. Main results and the role of chance The serum kisspeptin level of NZ was significantly higher than other groups (p < 0.05). The semen kisspeptin level was significantly higher than OAZ and OATZ (p < 0.05), but not in NZ (p > 0.05). Also, KISS1 gene expression was higher in AZ compared to other groups (p < 0.05). Biochemical and gene expression analysis of kisspeptin were consistent with each other. There was a significant increase in the expression of CATSPER1 gene in AZ compared to other groups (p < 0.05). Also, AKAP4 gene expression was significantly higher in OATZ compared to other groups (p < 0.05). No significant difference was documented for the expression of KISS1R (p > 0.05). Intracellular calcium was significantly increased in AZ and NZ after kisspeptin administration. The intracellular calcium increase is consistent with increased CATSPER1 gene expression levels in AZ. Kisspeptin administration may have a significant effect on sperm motility parameters. Limitations, reasons for caution The biochemical and gene expression levels of KISS1 were consistent. However, gene expression was explored at the mRNA level for CATSPER1 and AKAP4. The protein expression analyses of these genes may confirm the results. Also, using kisspeptin antagonists may strength the results of intracellular calcium analysis. Wider implications of the findings Kisspeptin treatment for individuals diagnosed with asthenozoospermia may have therapeutic results. KISS1 quantitation may be a determining factor for the subfertility in routine semen analysis. Trial registration number OMU KAEK 2019/462


2016 ◽  
Vol 10_2016 ◽  
pp. 64-72
Author(s):  
Safronova N.A. Safronova ◽  
Kalinina E.A. Kalinina ◽  
Donnikov A.E. Donnikov ◽  
Burmenskaya O.V. Burmenskaya ◽  
Makarova N.P. Makarova ◽  
...  

Author(s):  
T. R. Kannaki ◽  
P. C. Verma ◽  
M. R. Reddy ◽  
M. Shanmugam

TLR repertoire of duck, profiling of their mRNA expression in a range of duckling tissues and cytokine gene expressions upon TLR agonists stimulation in in vitro assay have been investigated. All ten TLR genes orthologous to chicken TLR repertoire were found in duck. Duck TLR genes showed 77-83% similarity at amino acid level to their chicken counterparts. All ten TLRs-TLR1LA, 1LB, 2A, 2B, 3, 4, 5, 7, 15 and 21 mRNA expressions were significantly higher in bursa than other tissues studied, whereas in muscle all TLRs mRNA expressions were significantly lower except for TLR15 (P>0.01). TLR7 gene expression was significantly higher in spleen, bursa and also in lung tissues (P>0.01). The cytokine gene expression levels in duck PBMCs upon LPS and poly I:C stimulation have been quantified. IL-1g gene expression level in LPS stimulated duck PBMC culture was significantly higher at both 12 h and 24 h time intervals (P>0.05). However, there were no significant changes in IFN-ã gene expression levels in poly I:C stimulated duck PBMC culture at both the intervals. TLR gene expression in young ducklings together with cytokine response upon LPS stimulation demonstrates the innate preparedness of younger birds to encounter pathogens and their functional ability to respond to their ligands.


2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 13034-13034
Author(s):  
M. Terashima ◽  
Y. Odashima ◽  
S. Ohtani ◽  
N. Soeta ◽  
F. Ohsuka ◽  
...  

13034 Background: We have previously reported that tumors with high orotate phosphoribosil transferase (OPRT) and low dihydropyrimidine dehydrogenase (DPD) mRNA expression levels showed remarkable sensitivity to 5-fluorouracil (5-FU) by real-time RT-PCR using fresh frozen (FF) tumor samples. However, the use of fresh frozen samples has some limitations. The use of formalin fixed parafine embedded (FFPE) samples has great advantage to apply these technologies for clinical settings. In order to investigate the feasibility of real-time RT-PCR from FFPE samples to predict sensitivitiy to 5-fluorouracil (5-FU), we investigated the gene expression levels of 5-FU metabolism-relating enzymes by real-time RT-PCR from FFPE samples and compared the results from FF samples in gastric and colorectal cancer. Methods: FFPE samples and FF samples were obtained from 46 patients with gastric cancer and 29 patients with colorectal cancer. Gene expression levels of tymidylate synthase (TS), OPRT, thymidine phosphorylase (TP) and DPD were determined by quantitative real-time RT-PCR. In FFPE samples tumor tissue was obtained using laser captured microdissection (LCM). Tumor sensitivity to 5-FU was evaluated by in vitro ATP assay. Results: Gene expression levels of TS, TP, DPD determined from FFPE samples significantly correlated with those from FF samples. Although respective gene expression levels alone failed to show signifcianct correlation with the in vitro 5-FU sensitivity, statistically significant correlation was noted either from the samples of FF or FFPE in both gastric (FF: r = 0.660, FFPE: r = 0.780) and colorectal cancer (FF: r = 0.780, FFPE: r = 0.660), when OPRT/DPD mRNA ratio was applied for comparison with the results of 5-FU sensitivity. Thus, high OPRT/DPD ratio determined from FFPE samples resulted in high sensitivity to 5-FU. Conclusions: From these results, it is suggested that sensitivity to 5-FU is predictable by quantitative RT-PCR using FFPE samples. Measurement of 5-FU metabolism-relating enzyme gene expression level from FFPE samples appeared to be feasible for predicting 5-FU sensitivity and to have great advantage to apply the molecular predicting assay in clinical settings. [Table: see text]


2020 ◽  
Vol 36 (12) ◽  
pp. 1031-1038
Author(s):  
Yong Fa Zhang ◽  
Jian Ying Yang ◽  
Xiang Ping Meng ◽  
Na Nie ◽  
Mei Cui Tang ◽  
...  

To explore the protective mechanism of L-arginine against T-2 toxin-induced apoptosis in mouse Leydig cells, we investigated whether L-arginine can prevent T-2 toxin-induced apoptosis in mouse Leydig cells and explored the underlying mechanisms. Leydig cells were isolated and cultured with control, T-2 toxin (10 nM), L-arginine (0.25, 0.5, and 1.0 mM), and T-2 toxin (10 nM T-2 toxin) + L-arginine (0.25, 0.5, or 1.0 mM) for 24 h. Cells and supernatants were harvested to examine proliferation of the cells, the apoptosis rate, activity of caspase-3 and mitochondria, and the gene expression levels of Bcl-2, Bax, PARP, and caspase-3. Results showed that proliferation and mitochondrial activity of Leydig cells were inhibited by administration of T-2 toxin. Bcl-2 gene expression levels was decreased, while the gene expression levels of Bax and PARP were increased, which could trigger mitochondria-mediated apoptosis, activate downstream caspase-3, and then increased caspase-3 at both activity and gene expression levels. The expression of the Bcl-2 gene was upregulated and the expression of Bax, caspase-3, and PARP gene were downregulated when L-arginine was added to the cultured cells. The results of this study showed that L-arginine could block T-2 toxin-induced apoptosis in mouse Leydig cells by regulating specific intracellular death-related pathways.


2010 ◽  
Vol 109 (5) ◽  
pp. 1483-1491 ◽  
Author(s):  
Marijke A. A. van Vlimmeren ◽  
Anita Driessen-Mol ◽  
Marloes van den Broek ◽  
Carlijn V. C. Bouten ◽  
Frank P. T. Baaijens

In vivo functionality of cardiovascular tissue engineered constructs requires in vitro control of tissue development to obtain a well developed extracellular matrix (ECM). We hypothesize that ECM formation and maturation is stimulated by culturing at low oxygen concentrations. Gene expression levels of monolayers of human vascular-derived myofibroblasts, exposed to 7, 4, 2, 1, and 0.5% O2( n = 9 per group) for 24 h, were measured for vascular endothelial growth factor (VEGF), procollagen α1(I) and α1(III), elastin, and cross-link enzymes lysyl oxidase (LOX) and lysyl hydroxylase 2 (LH2). After 4 days of exposure to 7, 2, and 0.5% O2( n = 3 per group), protein synthesis was evaluated. All analyses were compared with control cultures at 21% O2. Human myofibroblasts turned to hypoxia-driven gene expression, indicated by VEGF expression, at oxygen concentrations of 4% and lower. Gene expression levels of procollagen α1(I) and α1(III) increased to 138 ± 26 and 143 ± 19%, respectively, for all oxygen concentrations below 4%. At 2% O2, LH2 and LOX gene expression levels were higher than control cultures (340 ± 53 and 136 ± 29%, respectively), and these levels increased even further with decreasing oxygen concentrations (611 ± 176 and 228 ± 45%, respectively, at 0.5% O2). Elastin gene expression levels remained unaffected. Collagen synthesis and LH2 protein levels increased at oxygen concentrations of 2% and lower. Oxygen concentrations below 4% induce enhanced ECM production by human myofibroblasts. Implementation of these results in cardiovascular tissue engineering approaches enables in vitro control of tissue development.


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