Metallothionein gene regulation in the preimplantation rabbit blastocyst

Development ◽  
1987 ◽  
Vol 100 (3) ◽  
pp. 463-469
Author(s):  
G.K. Andrews ◽  
Y.M. Huet ◽  
L.D. Lehman ◽  
S.K. Dey

Expression of metallothionein (MT) genes in the preimplantation rabbit blastocyst was analysed by determination of the levels of MT mRNA and relative rates of MT synthesis. MT was found to be constitutively expressed at low levels in the blastocyst. Exposure of the day-6 blastocyst to zinc ions in vitro rapidly increased the level of MT gene expression in a dose-dependent manner, with a ten-fold induction in the relative rate of synthesis at 400 microM-Zn2+. Ion-exchange chromatography of pulse-labelled blastocyst protein showed that the relative rates of synthesis of both MT-I and MT-II were markedly increased following zinc treatment, with MT-I being the predominant isometallothionein. Zinc induction of MT synthesis in the blastocyst was also detected on day 4 of gestation just after the morula-to-blastocyst transition. In contrast to the zinc effects on MT, in vitro exposure to 10 microM-Cd2+ resulted in a large induction of MT mRNA but only a modest increase in the relative rate of MT synthesis. Cadmium was found to be toxic to the day-6 blastocyst, and 10 microM-Cd2+ induced an acute stress response as indicated by a dramatic induction of heat-shock protein (HSP-70) gene expression.

2019 ◽  
Vol 26 (7) ◽  
pp. 494-501 ◽  
Author(s):  
Sameer Suresh Bhagyawant ◽  
Dakshita Tanaji Narvekar ◽  
Neha Gupta ◽  
Amita Bhadkaria ◽  
Ajay Kumar Gautam ◽  
...  

Background: Diabetes and hypertension are the major health concern and alleged to be of epidemic proportions. This has made it a numero uno subject at various levels of investigation. Glucosidase inhibitor provides the reasonable option in treatment of Diabetes Mellitus (DM) as it specifically targets post prandial hyperglycemia. The Angiotensin Converting Enzyme (ACE) plays an important role in hypertension. Therefore, inhibition of ACE in treatment of elevated blood pressure attracts special interest of the scientific community. Chickpea is a food legume and seeds contain carbohydrate binding protein- a lectin. Some of the biological properties of this lectin hitherto been elucidated. Methods: Purified by ion exchange chromatography, chickpea lectin was tested for its in vitro antioxidant, ACE-I inhibitory and anti-diabetic characteristic. Results: Lectin shows a characteristic improvement over the synthetic drugs like acarbose (oral anti-diabetic drug) and captopril (standard antihypertensive drug) when, their IC50 values are compared. Lectin significantly inhibited α-glucosidase and α-amylase in a concentration dependent manner with IC50 values of 85.41 ± 1.21 ҝg/ml and 65.05 ± 1.2 µg/ml compared to acarbose having IC50 70.20 ± 0.47 value of µg/ml and 50.52 ± 1.01 µg/ml respectively. β-Carotene bleaching assay showed antioxidant activity of lectin (72.3%) to be as active as Butylated Hydroxylanisole (BHA). In addition, lectin demonstrated inhibition against ACE-I with IC50 value of 57.43 ± 1.20 µg/ml compared to captopril. Conclusion: Lectin demonstrated its antioxidant character, ACE-I inhibition and significantly inhibitory for α-glucosidase and α-amylase seems to qualify as an anti-hyperglycemic therapeutic molecule. The biological effects of chickpea lectin display potential for reducing the parameters of medically debilitating conditions. These characteristics however needs to be established under in vivo systems too viz. animals through to humans.


Nutrients ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 123
Author(s):  
Natalia K. Kordulewska ◽  
Justyna Topa ◽  
Małgorzata Tańska ◽  
Anna Cieślińska ◽  
Ewa Fiedorowicz ◽  
...  

Lipopolysaccharydes (LPS) are responsible for the intestinal inflammatory reaction, as they may disrupt tight junctions and induce cytokines (CKs) secretion. Osthole has a wide spectrum of pharmacological effects, thus its anti-inflammatory potential in the LPS-treated Caco-2 cell line as well as in Caco-2/THP-1 and Caco-2/macrophages co-cultures was investigated. In brief, Caco-2 cells and co-cultures were incubated with LPS to induce an inflammatory reaction, after which osthole (150–450 ng/mL) was applied to reduce this effect. After 24 h, the level of secreted CKs and changes in gene expression were examined. LPS significantly increased the levels of IL-1β, -6, -8, and TNF-α, while osthole reduced this effect in a concentration-dependent manner, with the most significant decrease when a 450 ng/mL dose was applied (p < 0.0001). A similar trend was observed in changes in gene expression, with the significant osthole efficiency at a concentration of 450 ng/μL for IL1R1 and COX-2 (p < 0.01) and 300 ng/μL for NF-κB (p < 0.001). Osthole increased Caco-2 monolayer permeability, thus if it would ever be considered as a potential drug for minimizing intestinal inflammatory symptoms, its safety should be confirmed in extended in vitro and in vivo studies.


1993 ◽  
Vol 264 (5) ◽  
pp. L465-L474 ◽  
Author(s):  
M. J. Acarregui ◽  
J. M. Snyder ◽  
C. R. Mendelson

Previously, it was found that lung explants from mid-trimester human abortuses differentiate spontaneously in organ culture in serum-free defined medium in an atmosphere of 95% air-5% CO2. Dibutyryl adenosine 3',5'-cyclic monophosphate (DBcAMP) treatment of human fetal lung in culture increases the rate of morphological differentiation and enhances expression of the surfactant protein A (SP-A) gene. To begin to define the factors responsible for this accelerated in vitro differentiation, we analyzed the effects of atmospheric oxygen on the morphological and biochemical development of human fetal lung in culture and on responsiveness of the cultured tissue to DBcAMP. We found that when lung explants were maintained in an atmosphere containing 1% oxygen they failed to differentiate spontaneously and no induction of SP-A gene expression was apparent. Furthermore, at 1% oxygen, DBcAMP had no effect to stimulate morphological differentiation or SP-A gene expression. When lung tissues that had been maintained for 5 days in 1% oxygen were transferred to an environment containing 20% oxygen, there was rapid morphological development and induction of SP-A gene expression. The effects on morphological development were manifest within 24 h of transfer to the 20% oxygen environment; within 72 h, a marked stimulatory effect of DBcAMP on SP-A gene expression also was observed. Our findings further suggest that the effects of oxygen on the levels of SP-A and SP-A mRNA are concentration dependent. Interestingly, the inductive effects of DBcAMP on SP-A gene expression were apparent only at oxygen concentrations > or = 10%. Morphological differentiation of the cultured human fetal lung tissue also was influenced by oxygen in a concentration-dependent manner. These findings suggest that oxygen plays an important permissive role in the spontaneous differentiation of human fetal lung in vitro.


Author(s):  
Yu Takahashi ◽  
Yu Inoue ◽  
Keitaro Kuze ◽  
Shintaro Sato ◽  
Makoto Shimizu ◽  
...  

Abstract Intestinal organoids better represent in vivo intestinal properties than conventionally used established cell lines in vitro. However, they are maintained in three-dimensional culture conditions that may be accompanied by handling complexities. We characterized the properties of human organoid-derived two-dimensionally cultured intestinal epithelial cells (IECs) compared with those of their parental organoids. We found that the expression of several intestinal markers and functional genes were indistinguishable between monolayer IECs and organoids. We further confirmed that their specific ligands equally activate intestinal ligand-activated transcriptional regulators in a dose-dependent manner. The results suggest that culture conditions do not significantly influence the fundamental properties of monolayer IECs originating from organoids, at least from the perspective of gene expression regulation. This will enable their use as novel biological tools to investigate the physiological functions of the human intestine.


Author(s):  
Mohammad Reza Shiran ◽  
Elham Mahmoudian ◽  
Abolghasem Ajami ◽  
Seyed Mostafa Hosseini ◽  
Ayjamal Khojasteh ◽  
...  

Abstract Objectives Angiogenesis is the most important challenge in breast cancer treatment. Recently, scientists become interesting in rare natural products and intensive researches was performed to identify their pharmacological profile. Auraptene shows helpful effects such as cancer chemo-preventive, anti-inflammatory, anti-oxidant, immuno-modulatory. In this regard, we investigated the anti-angiogenesis effect of Auraptene in in-vitro and in-vivo model of breast cancer. Methods In this study, 4T, MDA-MB-231 and HUVEC cell lines were used. The proliferation study was done by MTT assay. For tube formation assay, 250 matrigel, 1 × 104 HUVEC treated with Auraptene, 20 ng/mL EGF, 20 ng/mL bFGF and 20 ng/mL VEGF were used. Gene expression of important gene related to angiogenesis in animal model of breast cancer was investigated by Real-time PCR. Protein expression of VCAM-1 and TNFR-1 gene related to angiogenesis in animal model of breast cancer was investigated by western-blot. Results Auraptene treatment led to reduction in cell viability of MDA-MB-231 in a concentration-dependent manner. Also, we observed change in the number of tubes or branches formed by cells incubated with 40 and 80 μM Auraptene. Auraptene effect the gene expression of important gene related to angiogenesis (VEGF, VEGFR2, COX2, IFNɣ). Moreover, the western blot data exhibited that Auraptene effect the protein expression of VCAM-1 and TNFR-1. Conclusions Overall, this study shows that Auraptene significantly suppressed angiogenesis via down-regulation of VEGF, VEGFR2, VCAM-1, TNFR-1, COX-2 and up-regulation of IFNγ.


Parasitology ◽  
2000 ◽  
Vol 120 (6) ◽  
pp. 547-551 ◽  
Author(s):  
O. BILLKER ◽  
A. J. MILLER ◽  
R. E. SINDEN

Malarial gametocytes circulate in the peripheral blood of the vertebrate host as developmentally arrested intra-erythrocytic cells, which only resume development into gametes when ingested into the bloodmeal of the female mosquito vector. The ensuing development encompasses sexual reproduction and mediates parasite transmission to the insect. In vitro the induction of gametogenesis requires a drop in temperature and either a pH increase from physiological blood pH (ca pH 7·4) to about pH 8·0, or the presence of a gametocyte-activating factor recently identified as xanthurenic acid (XA). However, it is unclear whether either the pH increase or XA act as natural triggers in the mosquito bloodmeal. We here use pH-sensitive microelectrodes to determine bloodmeal pH in intact mosquitoes. Measurements taken in the first 30 min after ingestion, when malarial gametogenesis is induced in vivo, revealed small pH increases from 7·40 (mouse blood) to 7·52 in Aedes aegypti and to 7·58 in Anophěles stephensi. However, bloodmeal pH was clearly suboptimal if compared to values required to induce gametogenesis in vitro. Xanthurenic acid is shown to extend the pH-range of exflagellation in vitro in a dose-dependent manner to values that we have observed in the bloodmeal, suggesting that in vivo malarial gametogenesis could be further regulated by both these factors.


2006 ◽  
Vol 74 (5) ◽  
pp. 2985-2995 ◽  
Author(s):  
JoAnn M. Tufariello ◽  
Kaixia Mi ◽  
Jiayong Xu ◽  
Yukari C. Manabe ◽  
Anup K. Kesavan ◽  
...  

ABSTRACT Approximately one-third of the human population is latently infected with Mycobacterium tuberculosis, comprising a critical reservoir for disease reactivation. Despite the importance of latency in maintaining M. tuberculosis in the human population, little is known about the mycobacterial factors that regulate persistence and reactivation. Previous in vitro studies have implicated a family of five related M. tuberculosis proteins, called resuscitation promoting factors (Rpfs), in regulating mycobacterial growth. We studied the in vivo role of M. tuberculosis rpf genes in an established mouse model of M. tuberculosis persistence and reactivation. After an aerosol infection with the M. tuberculosis Erdman wild type (Erdman) or single-deletion rpf mutants to establish chronic infections in mice, reactivation was induced by administration of the nitric oxide (NO) synthase inhibitor aminoguanidine. Of the five rpf deletion mutants tested, one (ΔRv1009) exhibited a delayed reactivation phenotype, manifested by delayed postreactivation growth kinetics and prolonged median survival times among infected animals. Immunophenotypic analysis suggested differences in pulmonary B-cell responses between Erdman- and ΔRv1009-infected mice at advanced stages of reactivation. Analysis of rpf gene expression in the lungs of Erdman-infected mice revealed that relative expression of four of the five rpf-like genes was diminished at late times following reactivation, when bacterial numbers had increased substantially, suggesting that rpf gene expression may be regulated in a growth phase-dependent manner. To our knowledge, ΔRv1009 is the first M. tuberculosis mutant to have a specific defect in reactivation without accompanying growth defects in vitro or during acute infection in vivo.


1999 ◽  
Vol 19 (3) ◽  
pp. 2044-2050 ◽  
Author(s):  
Seok Hee Park ◽  
Sang Seok Koh ◽  
Jae Hwan Chun ◽  
Hye Jin Hwang ◽  
Hyen Sam Kang

ABSTRACT Expression of genes encoding starch-degrading enzymes is regulated by glucose repression in the yeast Saccharomyces cerevisiae. We have identified a transcriptional repressor, Nrg1, in a genetic screen designed to reveal negative factors involved in the expression of STA1, which encodes a glucoamylase. TheNRG1 gene encodes a 25-kDa C2H2zinc finger protein which specifically binds to two regions in the upstream activation sequence of the STA1 gene, as judged by gel retardation and DNase I footprinting analyses. Disruption of theNRG1 gene causes a fivefold increase in the level of theSTA1 transcript in the presence of glucose. The expression of NRG1 itself is inhibited in the absence of glucose. DNA-bound LexA-Nrg1 represses transcription of a target gene 10.7-fold in a glucose-dependent manner, and this repression is abolished in bothssn6 and tup1 mutants. Two-hybrid and glutathione S-transferase pull-down experiments show an interaction of Nrg1 with Ssn6 both in vivo and in vitro. These findings indicate that Nrg1 acts as a DNA-binding repressor and mediates glucose repression of the STA1 gene expression by recruiting the Ssn6-Tup1 complex.


Archaea ◽  
2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Jennifer Gebetsberger ◽  
Marek Zywicki ◽  
Andrea Künzi ◽  
Norbert Polacek

Nonprotein coding RNA (ncRNA) molecules have been recognized recently as major contributors to regulatory networks in controlling gene expression in a highly efficient manner. These RNAs either originate from their individual transcription units or are processing products from longer precursor RNAs. For example, tRNA-derived fragments (tRFs) have been identified in all domains of life and represent a growing, yet functionally poorly understood, class of ncRNA candidates. Here we present evidence that tRFs from the halophilic archaeonHaloferax volcaniidirectly bind to ribosomes. In the presented genomic screen of the ribosome-associated RNome, a 26-residue-long fragment originating from the 5′ part of valine tRNA was by far the most abundant tRF. The Val-tRF is processed in a stress-dependent manner and was found to primarily target the small ribosomal subunitin vitroandin vivo. As a consequence of ribosome binding, Val-tRF reduces protein synthesis by interfering with peptidyl transferase activity. Therefore this tRF functions as ribosome-bound small ncRNA capable of regulating gene expression inH. volcaniiunder environmental stress conditions probably by fine tuning the rate of protein production.


2021 ◽  
Author(s):  
Léa Malo ◽  
Valentin Do Sacramento ◽  
Christian Gachet ◽  
François Lanza ◽  
Henri de la Salle ◽  
...  

Human CD34+ progenitors can be differentiated in vitro into proplatelet-producing megakaryocytes (MKs) within 17 days. During this time, four cell populations emerge, phenotypically defined as CD34+CD41+ on day 7 (D7) and CD34+CD41+CD9- on D10 and D14 - qualified as productive because they can differentiate into proplatelet-forming cells during the D14-D17 period - and CD34-CD41+ or CD34+CD41+CD9+ on day 10 - qualified as unproductive because they are unable to form proplatelets later. Coculture with mesenchymal stem cells, or the presence of the AHR antagonist SR1, boosts the productive pathway in two ways: firstly, it increases the yield of D10 and D14 CD34+CD41+CD9- cells and secondly, it greatly increases their ability to generate proplatelets; in contrast, SR1 has no noticeable effect on the unproductive cell types. A transcriptome analysis was performed to decipher the genetic basis of these properties. This work represents the first extensive description of the genetic perturbations which accompany the differentiation of CD34+ progenitors into mature MKs at a subpopulation level. It highlights a wide variety of biological changes modulated in a time-dependent manner and allows anyone, according to his/her interests, to focus on specific biological processes accompanying MK differentiation. For example, the modulation of the expression of genes associated with cell proliferation, lipid and cholesterol synthesis, extracellular matrix components, intercellular interacting receptors and MK and platelet functions reflected the chronological development of the productive cells and pointed to unsuspected pathways. Surprisingly, SR1 only affected the gene expression profile of D10 CD34+CD41+CD9- cells; thus, as compared to these cells and those present on D14, the poorly productive D10 CD34+CD41+CD9- cells obtained in the absence of SR1 and the two unproductive populations present on D10 displayed an intermediate gene expression pattern. In other words, the ability to generate proplatelets between D10 and D14 appeared to be linked to the capacity of SR1 to delay MK differentiation, meanwhile avoiding intermediate and inappropriate genetic perturbations. Paradoxically, the D14 CD34+CD41+CD9- cells obtained under SR1- or SR1+ conditions were virtually identical, raising the question as to whether their strong differences in terms of proplatelet production, in the absence of SR1 and between D14 and D17, are mediated by miRNAs or by memory post-translational regulatory mechanisms.


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