scholarly journals Effects of 5-Fluorodeoxyuridine and Related Halogenated Pyrimidines on the Sand-Dollar Embryo

1960 ◽  
Vol 7 (1) ◽  
pp. 61-71 ◽  
Author(s):  
David A. Karnofsky ◽  
Ross S. Basch
Keyword(s):  
Embryonic Development ◽  
Random Pattern ◽  
Protective Agent ◽  
Sand Dollar ◽  
Blastula Stage ◽  
Bacterial Dna ◽  
Fluorinated Pyrimidines ◽  
Minimal Lethal Concentration ◽  
Embryonic Death

The embryo of the sand-dollar (Echinarachnius parma) was exposed to various concentrations of fluorinated pyrimidines immediately after fertilization. FUDR (5-fluorodeoxyuridine) was most active, and a concentration of 2 to 4 mγ/10 cc. (0.8 to 1.6 x 10-6 m.eq./liter) blocked development at the early blastula stage. Larger doses interrupted development at the same stage. This effect was prevented by thymidine (TDR) and thymine (T); and these pyrimidines protected against many times the minimal lethal concentration of FUDR. TDR was active as a protective agent if added just before early blastula formation. The other fluorinated pyrimidines, 5-fluorouracil (FU), 5-fluorouridine (FUR), 5-fluorocytidine (FCR), 5-fluorodeoxycytidine (FCDR), and 5-fluoroorotic acid (FO), were also studied. These drugs produced effects on embryonic development similar to those seen with FUDR. The effective concentrations, however, varied greatly. T and TDR provided protection against these drugs, but in most cases they were not so effective as against FUDR. 5-Bromodeoxyurdine (BrUDR), beginning at the early blastula stage, caused a random pattern of embryonic death up to the pluteus stage. This drug has been shown to be incorporated into bacterial DNA. BrUDR protected embryos against the early lethal effects of FUDR presumably acting as a thymidine substitute, but the embryos died subsequently in a pattern similar to that seen with BrUDR alone. FUDR and BrUDR appear to inhibit the formation and alter the structure of DNA, respectively, distinctive effects whch may provide a means for studying the role of DNA in embryonic development.

scholarly journals Inhibition of Aurora Kinase B activity disrupts development and differentiation of salivary glands

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Abeer K. Shaalan ◽  
Tathyane H. N. Teshima ◽  
Abigail S. Tucker ◽  
Gordon B. Proctor
Keyword(s):  
Cell Cycle ◽  
Embryonic Development ◽  
Salivary Glands ◽  
Aurora Kinase ◽  
Serine Threonine Kinase ◽  
Aurora Kinase B ◽  
Development And Differentiation ◽  
Differentiation Marker ◽  
Key Events

AbstractLittle is known about the key molecules that regulate cell division during organogenesis. Here we determine the role of the cell cycle promoter aurora kinase B (AURKB) during development, using embryonic salivary glands (E-SGs) as a model. AURKB is a serine/threonine kinase that regulates key events in mitosis, which makes it an attractive target for tailored anticancer therapy. Many reports have elaborated on the role of AURKB in neoplasia and cancer; however, no previous study has shown its role during organ development. Our previous experiments have highlighted the essential requirement for AURKB during adult exocrine regeneration. To investigate if AURKB is similarly required for progression during embryonic development, we pharmacologically inhibited AURKB in developing submandibular glands (SMGs) at embryonic day (E)13.5 and E16.5, using the highly potent and selective drug Barasertib. Inhibition of AURKB interfered with the expansion of the embryonic buds. Interestingly, this effect on SMG development was also seen when the mature explants (E16.5) were incubated for 24 h with another cell cycle inhibitor Aphidicolin. Barasertib prompted apoptosis, DNA damage and senescence, the markers of which (cleaved caspase 3, γH2AX, SA-βgal and p21, respectively), were predominantly seen in the developing buds. In addition to a reduction in cell cycling and proliferation of the epithelial cells in response to AURKB inhibition, Barasertib treatment led to an excessive generation of reactive oxygen species (ROS) that resulted in downregulation of the acinar differentiation marker Mist1. Importantly, inhibition of ROS was able to rescue this loss of identity, with Mist1 expression maintained despite loss of AURKB. Together, these data identify AURKB as a key molecule in supporting embryonic development and differentiation, while inhibiting senescence-inducing signals during organogenesis.

scholarly journals The role of ascorbic acid combined exposure on Imidacloprid-induced oxidative stress and genotoxicity in Nile tilapia

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Islam M. El-Garawani ◽  
Elsayed A. Khallaf ◽  
Alaa A. Alne-na-ei ◽  
Rehab G. Elgendy ◽  
Gaber A. M. Mersal ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Ascorbic Acid ◽  
Nile Tilapia ◽  
Protective Agent ◽  
Strand Breaks ◽  
Gill Cells ◽  
Significant Amelioration ◽  
Neonicotinoid Insecticide ◽  
Dna Strand

AbstractImidacloprid (Imid), a systemic neonicotinoid insecticide, is broadly used worldwide. It is reported to contaminate aquatic systems. This study was proposed to evaluate oxidative stress and genotoxicity of Imid on Nile tilapia (Oreochromis niloticus) and the protective effect of ascorbic acid (Asc). O. niloticus juveniles (30.4 ± 9.3 g, 11.9 ± 1.3 cm) were divided into six groups (n = 10/replicate). For 21 days, two groups were exposed to sub-lethal concentrations of Imid (8.75 ppm, 1/20 of 72 h-LC50 and 17.5 ppm, 1/10 of 72 h-LC50); other two groups were exposed to Asc (50 ppm) in combination with Imid (8.75 and 17.5 ppm); one group was exposed to Asc (50 ppm) in addition to a group of unexposed fish which served as controls. Oxidative stress was assessed in the liver where the level of enzymatic activities including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in addition to mRNA transcripts and, Lipid peroxidation (LPO) were evaluated. Moreover, mitotic index (MI) and comet assay were performed, in addition, the erythrocytic micronucleus (MN), and nuclear abnormalities (NA) were observed to assess genotoxicity in fish. Imid exposure induced significant (p ˂ 0.05) changes in the antioxidant profile of the juveniles' liver by increasing the activities and gene expression of SOD, CAT and GPX as well as elevating the levels of LPO. DNA strand breaks in gill cells, erythrocytes and hepatocytes along with erythrocytic MN and NA were also significantly elevated in Imid-exposed groups. MI showed a significant (p ˂ 0.05) decrease associated with Imid exposure. Asc administration induced a significant amelioration towards the Imid toxicity (8.75 and 17.5 ppm). A significant protective potency against the genotoxic effects of Imid was evidenced in Asc co-treated groups. Collectively, results highlight the importance of Asc as a protective agent against Imid-induced oxidative stress and genotoxicity in O. niloticus juveniles.

Temperature-dependence of the DnaA–DNA interaction and its effect on the autoregulation of dnaA expression

2012 ◽  
Vol 449 (2) ◽  
pp. 333-341 ◽  
Author(s):  
Chiara Saggioro ◽  
Anne Olliver ◽  
Bianca Sclavi
Keyword(s):  
Temperature Dependence ◽  
Binding Sites ◽  
Dna Interaction ◽  
Bacterial Dna ◽  
Dnaa Protein ◽  
High Affinity ◽  
Key Factor

The DnaA protein is a key factor for the regulation of the timing and synchrony of initiation of bacterial DNA replication. The transcription of the dnaA gene in Escherichia coli is regulated by two promoters, dnaAP1 and dnaAP2. The region between these two promoters contains several DnaA-binding sites that have been shown to play an important role in the negative auto-regulation of dnaA expression. The results obtained in the present study using an in vitro and in vivo quantitative analysis of the effect of mutations to the high-affinity DnaA sites reveal an additional effect of positive autoregulation. We investigated the role of transcription autoregulation in the change of dnaA expression as a function of temperature. While negative auto-regulation is lost at dnaAP1, the effects of both positive and negative autoregulation are maintained at the dnaAP2 promoter upon lowering the growth temperature. These observations can be explained by the results obtained in vitro showing a difference in the temperature-dependence of DnaA–ATP binding to its high- and low-affinity sites, resulting in a decrease in DnaA–ATP oligomerization at lower temperatures. The results of the present study underline the importance of the role for autoregulation of gene expression in the cellular adaptation to different growth temperatures.

scholarly journals Ascorbic acid improves parthenogenetic embryo development through TET proteins in mice

2019 ◽  
Vol 39 (1) ◽  
Author(s):  
Wei Gao ◽  
Xianfeng Yu ◽  
Jindong Hao ◽  
Ling Wang ◽  
Minghui Qi ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Vitamin C ◽  
Embryonic Development ◽  
Real Time Pcr ◽  
Quantitative Real Time Pcr ◽  
Qrt Pcr ◽  
Tet Proteins ◽  
Parthenogenetic Embryo ◽  
Blastocyst Rate

Abstract The TET (Ten-Eleven Translocation) proteins catalyze the oxidation of 5mC (5-methylcytosine) to 5hmC (5-hydroxymethylcytosine) and play crucial roles in embryonic development. Ascorbic acid (Vc, Vitamin C) stimulates the expression of TET proteins, whereas DMOG (dimethyloxallyl glycine) inhibits TET expression. To investigate the role of TET1, TET2, and TET3 in PA (parthenogenetic) embryonic development, Vc and DMOG treatments were administered during early embryonic development. The results showed that Vc treatment increased the blastocyst rate (20.73 ± 0.46 compared with 26.57 ± 0.53%). By contrast, DMOG reduced the blastocyst rate (20.73 ± 0.46 compared with 11.18 ± 0.13%) in PA embryos. qRT-PCR (quantitative real-time PCR) and IF (immunofluorescence) staining results revealed that TET1, TET2, and TET3 expressions were significantly lower in PA embryos compared with normal fertilized (Con) embryos. Our results revealed that Vc stimulated the expression of TET proteins in PA embryos. However, treatment with DMOG significantly inhibited the expression of TET proteins. In addition, 5hmC was increased following treatment with Vc and suppressed by DMOG in PA embryos. Taken together, these results indicate that the expression of TET proteins plays crucial roles mediated by 5hmC in PA embryonic development.

scholarly journals Review: The endless nutritional and pharmaceutical benefits of the Himalayan gold, Cordyceps; Current knowledge and prospective potentials

2020 ◽  
Vol 18 (2) ◽  
Author(s):  
Waill Elkhateeb ◽  
Ghoson Daba
Keyword(s):  
Current Knowledge ◽  
Health Benefits ◽  
Chemical Compounds ◽  
Food Supplement ◽  
In Vivo Studies ◽  
Protective Agent ◽  
Global Marketplace

Abstract. Elkhateeb WA, Daba GM. 2020. Review: The endless nutritional and pharmaceutical benefits of the Himalayan gold, Cordyceps; Current knowledge and prospective potentials. Biofarmasi J Nat Prod Biochem 18: 70-77. As a traditional medicine, Cordyceps has long been used in Asian nations for maintaining vivacity and boosting immunity. Numerous publications on various bioactivities of Cordyceps have been investigated in both in-vitro as well as in vivo studies. Nevertheless, the role of Cordyceps is still arguable whether it acts as food supplement for health benefits or a real healing drug that can be prescribed in medicine. The Cordyceps industry has developed greatly and offers thousands of products, commonly available in a global marketplace. In this review, focus will be on introducing the ecology of Cordyceps and their classification. Moreover, elucidation of the richness of extracts originated from this mushroom in nutritional components was presented, with description of the chemical compounds of Cordyceps and its well-known compounds such as cordycepin, and cordycepic acid. Furthermore, highlights on natural growth and artificial cultivation of famous Cordyceps species were presented. The health benefits and reported bioactivities of Cordyceps species as promising antimicrobial, anticancer, hypocholesterolemic, antioxidant, antiviral, anti-inflammatory, organ protective agent, and enhancer for organ function were presented.

scholarly journals Lipids: Role in Embryonic Development (Review)

2019 ◽  
pp. 1-9
Author(s):  
Marisol León ◽  
A. C. B. Rodrigues ◽  
A. O. M. Turquetti ◽  
A. D. Cereta ◽  
L. F. Melo ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Bone Cells ◽  
Bone Mineralization ◽  
Membrane Integrity ◽  
Cell Membrane Integrity ◽  
Muscle Formation ◽  
Neural Apoptosis ◽  
Neural Survival ◽  
Transport Molecules

Aims: We propose to briefly review the specific role of lipids in embryonic structures development. Results: Lipids are organic substances insoluble in water, divided into several classes, such as fatty acids, glycolipids, phospholipids, ceramides, sphingolipids, and stereo-lipids. They participate in processes of cellular metabolism and embryonic development which are associated with signalling, proliferation and cell migration. They act in developmental processes such as calcification and bone mineralization, pulmonary maturity, cellular differentiation, and neural survival, epithelial cells polarization and muscle formation, in which phospholipids as a major group, work more regularly. Lipids during embryonic development work directly as transport molecules or cell markers. In addition to an imbalance in its enzymatic and protein precursors (such as choline kinase), lipids can increase or decrease lipid concentration in cells, prevent its biotransformation, or affect its synergy with other molecules, leading to failures in the formation of organs such as the heart, brain, and bones. This aims to further the understanding of these processes and highlight its feasibility for future clinical applications. Conclusion: Lipids maintain cell membrane integrity in blastocysts, transport calcium to nerve and bone cells, facilitate neural apoptosis, and promote pulmonary maturation. These results aid in the understanding and prediction of alterations in lipidic metabolic syndromes in several pathological disorders during organ development.

scholarly journals Discovery of pluripotency-associated microRNAs in rabbit preimplantation embryos and embryonic stem-like cells

Reproduction ◽  
2013 ◽  
Vol 145 (4) ◽  
pp. 421-437 ◽  
Author(s):  
Pouneh Maraghechi ◽  
László Hiripi ◽  
Gábor Tóth ◽  
Babett Bontovics ◽  
Zsuzsanna Bősze ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Cell Biology ◽  
Embryonic Stem ◽  
Blastocyst Stage ◽  
Expression Level ◽  
Preimplantation Embryos ◽  
Regulatory Function ◽  
Low Level ◽  
Non Coding Rnas

MicroRNAs (miRNAs) are small non-coding RNAs that regulate multiple biological processes. Increasing experimental evidence implies an important regulatory role of miRNAs during embryonic development and in embryonic stem (ES) cell biology. In the current study, we have described and analyzed the expression profile of pluripotency-associated miRNAs in rabbit embryos and ES-like cells. The rabbit specific ocu-miR-302 and ocu-miR-290 clusters, and three homologs of the human C19MC cluster (ocu-miR-512, ocu-miR-520e, and ocu-miR-498) were identified in rabbit preimplantation embryos and ES-like cells. The ocu-miR-302 cluster was highly similar to its human homolog, while ocu-miR-290 revealed a low level of evolutionary conservation with its mouse homologous cluster. The expression of the ocu-miR-302 cluster began at the 3.5 days post-coitum early blastocyst stage and they stayed highly expressed in rabbit ES-like cells. In contrast, a high expression level of the ocu-miR-290 cluster was detected during preimplantation embryonic development, but a low level of expression was found in rabbit ES-like cells. Differential expression of the ocu-miR-302 cluster and ocu-miR-512 miRNA was detected in rabbit trophoblast and embryoblast. We also found that Lefty has two potential target sites in its 3′UTR for ocu-miR-302a and its expression level increased upon ocu-miR-302a inhibition. We suggest that the expression of the ocu-miR-302 cluster is characteristic of the rabbit ES-like cell, while the ocu-miR-290 cluster may play a crucial role during early embryonic development. This study presents the first identification, to our knowledge, of pluripotency-associated miRNAs in rabbit preimplantation embryos and ES-like cells, which can open up new avenues to investigate the regulatory function of ocu-miRNAs in embryonic development and stem cell biology.

Role of the HOXA cluster in HSC emergence and blood cancer

2021 ◽  
Author(s):  
Mays Abuhantash ◽  
Emma M. Collins ◽  
Alexander Thompson
Keyword(s):  
Embryonic Development ◽  
Hox Genes ◽  
Hoxa Cluster ◽  
Hematopoietic Stem ◽  
Blood Cancer ◽  
Non Coding Rna ◽  
Blood Formation ◽  
Peripheral Cells ◽  
Normal Embryonic Development

Hematopoiesis, the process of blood formation, is controlled by a complex developmental program that involves intrinsic and extrinsic regulators. Blood formation is critical to normal embryonic development and during embryogenesis distinct waves of hematopoiesis have been defined that represent the emergence of hematopoietic stem or progenitor cells. The Class I family of homeobox (HOX) genes are also critical for normal embryonic development, whereby mutations are associated with malformations and deformity. Recently, members of the HOXA cluster (comprising 11 genes and non-coding RNA elements) have been associated with the emergence and maintenance of long-term repopulating HSCs. Previous studies identified a gradient of HOXA expression from high in HSCs to low in circulating peripheral cells, indicating their importance in maintaining blood cell numbers and differentiation state. Indeed, dysregulation of HOXA genes either directly or by genetic lesions of upstream regulators correlates with a malignant phenotype. This review discusses the role of the HOXA cluster in both HSC emergence and blood cancer formation highlighting the need for further research to identify specific roles of these master regulators in normal and malignant hematopoiesis.

Abstract 052: Epicardial-derived Adrenomedullin Drives Cardiac Hyperplasia During Embryogenesis

2013 ◽  
Vol 113 (suppl_1) ◽  
Author(s):  
Sarah E Wetzel-Strong ◽  
Manyu Li ◽  
Toshio Nishikimi ◽  
Kathleen M Caron
Keyword(s):  
Embryonic Development ◽  
Heart Development ◽  
Cardiac Development ◽  
Lymphatic Vessels ◽  
Heart Weight ◽  
Cardiovascular Development ◽  
Proliferating Cells ◽  
Over Expression ◽  
Knockout Animals

The multi-functional peptide adrenomedullin ( Adm = gene, AM = protein) plays important roles in embryonic development and disease. Previous studies demonstrated that Adm knockout mice die at embryonic day 13.5 with small, disorganized hearts and hypoplastic lymphatic vessels, highlighting the importance of this peptide in normal cardiovascular development. Since Adm knockout animals are embryonic lethal, our goal was to generate and characterize a novel model of Adm over-expression to study the role of Adm during development and disease processes. Through gene targeting techniques, we generated a novel mouse model of Adm over-expression, abbreviated as Adm hi/hi . When we assessed gene expression of Adm from 10 different tissues, we found Adm hi/hi mice express 3- to 15-fold more Adm than wildtype littermates. Additionally, peptide levels of AM in lung and kidney, as well as circulating plasma levels of AM were elevated 3-fold over wildtype mice, indicating a functional increase in AM. Our initial analysis revealed that adult Adm hi/hi mice have larger heart weight to body weight ratios than wildtype littermates (4.93±0.23 vs. 5.96±0.29, n = 11-12). We found that compared to wildtype, Adm hi/hi embryos have more proliferating cells during heart development (14.46±1.11 vs. 31.97±2.84, n=4), indicating that hyperplasia drives Adm hi/hi heart enlargement. By crossing the Adm hi/hi line to different tissue-specific Cre lines, we were able to excise the stabilizing bovine growth hormone 3’UTR, thereby returning Adm expression levels back to wildtype in cells with active Cre recombinase. Using this approach, we identified the epicardium as a major source of AM during cardiac development. In conclusion, we found that AM derived primarily from the epicardium drives cardiac hyperplasia during embryonic development resulting in persistent, enlarged hearts of adult Adm hi/hi mice. Since our Adm hi/hi mice recapitulate the 3-fold plasma elevation of AM observed during human disease, this mouse line will be a useful tool for studying the role of elevated AM during disease.

Sign in / Sign up

Export Citation Format

Share Document