scholarly journals Clinical Implications and Translation of an Off-Target Pharmacology Profiling Hit: Adenosine Uptake Inhibition In Vitro

2019 ◽  
Vol 12 (10) ◽  
pp. 1296-1304
Author(s):  
Hamid R. Amouzadeh ◽  
Isaiah Dimery ◽  
Jonathan Werner ◽  
Gataree Ngarmchamnanrith ◽  
Michael J Engwall ◽  
...  
Keyword(s):  
Clinical Implications ◽  
Uptake Inhibition ◽  
Adenosine Uptake

The EYTEX™ System and the Neutral Red Uptake Inhibition Assay in Cultured Hep G2 Cells as Alternative Methods for In Vivo Eye Irritation Following the EEC Protocol

1990 ◽  
Vol 17 (4) ◽  
pp. 325-333
Author(s):  
Paul J. Dierickx ◽  
Virginia C. Gordon
Keyword(s):  
Neutral Red ◽  
Alternative Methods ◽  
Inhibition Assay ◽  
Hep G2 ◽  
Hep G2 Cells ◽  
Eye Irritation ◽  
Uptake Inhibition ◽  
In Vitro Methods ◽  
Neutral Red Uptake

The neutral red uptake inhibition assay and the EYTEX™ system were investigated as alternative methods for the assessment of eye irritation, determined according to the EEC protocol. The 17 test chemicals used were mainly organic solvents. The xenobiotics were applied to Hep G2 cells for 24 hours at different concentrations. Neutral red uptake inhibition was then measured. The results are expressed as the NI50 value, which is the concentration of test compound required to induce a 50% reduction in neutral red uptake. The same chemicals were also tested as coded samples by the EYTEX™ test according to the manufacturer's directions. A nearly identical quantitative correlation was found for both in vitro methods with corneal opacity scores: r = 0.84 for EYTEX™ scores and r = 0.83 for log NI50, expressed in μg/ml. Whilst these correlations are certainly not perfect, it is clear that both in vitro methods can be used as valuable prescreening methods.

Drug Susceptibility of the Mycobacterium Genus: In Vitro Tests and Clinical Implications

2006 ◽  
Vol 1 (3) ◽  
pp. 277-289 ◽  
Author(s):  
J. Rodriguez ◽  
E. Garcia-Pachon ◽  
M. Ruiz ◽  
G. Royo
Keyword(s):  
Drug Susceptibility ◽  
In Vitro Tests ◽  
Clinical Implications

scholarly journals Stem cell signature in glioblastoma: therapeutic development for a moving target

2015 ◽  
Vol 122 (2) ◽  
pp. 324-330 ◽  
Author(s):  
Ichiro Nakano
Keyword(s):  
High Grade Glioma ◽  
Core Gene ◽  
Metabolic Reprogramming ◽  
Molecular Signature ◽  
Transcriptional Analysis ◽  
Clinical Implications ◽  
Pathways Analysis ◽  
Therapeutic Development

Tumor heterogeneity of adult high-grade glioma (HGG) is recognized in 3 major subtypes based on core gene signatures. However, the molecular signatures and clinical implications of glioma stem cells (GSCs) in individual HGG subtypes remain poorly characterized. Recently genome-wide transcriptional analysis identified two mutually exclusive GSC subtypes with distinct dysregulated signaling and metabolic pathways. Analysis of genetic profiles and phenotypic assays distinguished proneural (PN) from mesenchymal (MES) GSCs and revealed a striking correlation with the corresponding PN or MES HGGs. Similar to HGGs with a MES signature, MES GSCs display more aggressive phenotypes both in vitro and in vivo. Furthermore, MES GSCs are markedly resistant to radiation as compared with PN GSCs, consistent with the relative radiation resistance of MES GBM compared with other subtypes. A systems biology approach has identified a set of transcription factors as the master regulators for the MES signature. Metabolic reprogramming in MES GSCs has also been noticed with the prominent activation of the glycolytic pathway, comprising aldehyde dehydrogenase (ALDH) family genes. This review summarizes recent progress in the characterization of the molecular signature in distinct HGG and GSC subtypes and plasticity between different GSC subtypes as well as between GSCs and non-GSCs in HGG tumors. Clinical implications of the translational GSC research are also discussed.

scholarly journals Effect of the proinflammatory cytokine TNF-α on intestinal riboflavin uptake: inhibition mediated via transcriptional mechanism(s)

2018 ◽  
Vol 315 (5) ◽  
pp. C653-C663 ◽  
Author(s):  
Kasin Yadunandam Anandam ◽  
Omar A. Alwan ◽  
Veedamali S. Subramanian ◽  
Padmanabhan Srinivasan ◽  
Rubina Kapadia ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Significant Inhibition ◽  
Mrna Levels ◽  
In Vivo Models ◽  
Uptake Inhibition ◽  
Tnf Α ◽  
Vitro Model ◽  
Factor Α

Riboflavin (RF), is essential for normal cellular metabolism/function. Intestinal RF absorption occurs via a specific carrier-mediated process that involves the apical transporter RFVT-3 ( SLC52A3) and the basolateral RFVT-1 (SLC52A1). Previously, we characterized different cellular/molecular aspects of the intestinal RF uptake process, but nothing is known about the effect of proinflammatory cytokines on the uptake event. We addressed this issue using in vitro, ex vivo, and in vivo models. First, we determined the level of mRNA expression of the human (h)RFVT-3 and hRFVT-1 in intestinal tissue of patients with inflammatory bowel disease (IBD) and observed a markedly lower level compared with controls. In the in vitro model, exposing Caco-2 cells to tumor necrosis factor-α (TNF-α) led to a significant inhibition in RF uptake, an effect that was abrogated upon knocking down TNF receptor 1 (TNFR1). The inhibition in RF uptake was associated with a significant reduction in the expression of hRFVT-3 and -1 protein and mRNA levels, as well as in the activity of the SLC52A3 and SLC52A1 promoters. The latter effects appear to involve Sp1 and NF-κB sites in these promoters. Similarly, exposure of mouse small intestinal enteroids and wild-type mice to TNF-α led to a significant inhibition in physiological and molecular parameters of intestinal RF uptake. Collectively, these findings demonstrate that exposure of intestinal epithelial cells to TNF-α leads to inhibition in RF uptake and that this effect is mediated, at least in part, via transcriptional mechanism(s). These findings may explain the significantly low RF levels observed in patients with IBD.

scholarly journals Binding of Dipyridamole of Human Platelets and to α-Acid Glycoprotein and its Significance for the Inhibition of Adenosine Uptake

1977 ◽  
Author(s):  
K. Subbarao ◽  
B. Rucinski ◽  
A. Summers ◽  
S. Niewiarowski
Keyword(s):  
Binding Sites ◽  
Ex Vivo ◽  
Human Platelets ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Acid Glycoprotein ◽  
High Affinity ◽  
Adenosine Uptake ◽  
Adenosine Transport

The interactions of dipyridamole with α1-acid glycoprotein of plasma and with human platelets are related to inhibition of adenosine uptake by platelets. One mole of dipyridamole binds to one mole of α1-acid glycoprotein with a dissociation constant (Kd) of 1.3 μM. It was found that platelets contain both high and low affinity binding sites for the drug. The binding of dipyridamole to the high affinity sites follows a Michaelis Menten binding pattern with a Kd of 0.04 μM. Approximately 2x104 dipyridamole molecules are bound at the high affinity sites of each platelet. The lower affinity sites bind the drug with a Kd of 4 μM. In the presence of α1acid glycoprotein the binding of dipyridamole to platelets is inhibited. Correspondingly, the dipyridamole inhibition of adenosine uptake by platelets is reduced 1000-fold by α1acid glycoprotein. Binding of dipyridamole to human platelets is essential for its inhibition of adenosine uptake by platelets. Dipyridamole reduced the [14C]-ATP to [14C]-ADP ratio in the platelets. Purified α1acid glycoprotein reversed these effects of dipyridamole on adenosine metabolism of platelets in a concentration dependent manner. A correlationwas observed between the level of circulating dipyridamole in plasma and the inhibition of [14C]-adenosine uptake by platelets of PRP samples of 12 human volunteers given different amounts of dipyridamole. The in vitro and ex vivo effects of dipyridamole on the [14C]-adenosine uptake by platelets were found to be identical. Our data suggest the presence of dipyridamole binding sites in platelets that regulate adenosine transport across the cell surface.

In Vitro Study of Peritoneal Fibrosis

2007 ◽  
Vol 27 (2_suppl) ◽  
pp. 72-75
Author(s):  
Kuan-Yu Hung ◽  
Kuan-Dun Wu ◽  
Tun-Jun Tsai
Keyword(s):  
Therapeutic Potential ◽  
In Vitro Study ◽  
In Vitro Models ◽  
Drop Out ◽  
Clinical Implications ◽  
Peritoneal Fibrosis ◽  
Asian Studies ◽  
Peritoneal Tissue ◽  
Matrix Accumulation

Peritoneal fibrosis (PF) is an important issue in peritoneal dialysis (PD) because it remains one of the leading causes of patient drop-out from PD. In this review, we focus on in vitro approaches to the pathogenesis and therapeutic potential of PF and on associated clinical implications. Representative Asian studies, initiated since mid-1990s, that have investigated matrix accumulation in peritoneal tissue possibly leading to PF in the PD population will be highlighted as examples to learn how to apply this research tool. As compared with data from well-designed clinical trials, observations from in vitro models may be far from becoming solid evidence; however, they do cast new light on options for investigations into therapeutic pharmaceuticals.

Sign in / Sign up

Export Citation Format

Share Document