scholarly journals In Vivo Nonlinear Light Scattering Probe of Drug-Induced Activation of Bacterial Mechanosensitive Channels

2017 ◽  
Vol 112 (3) ◽  
pp. 580a
Author(s):  
Mohammad Sharifian Gh ◽  
Charles D. Cox ◽  
Michael J. Wilhelm ◽  
Hai-Lung Dai
Keyword(s):  
Light Scattering ◽  
Mechanosensitive Channels ◽  
Drug Induced ◽  
Nonlinear Light Scattering

scholarly journals Enhancement of hepatic 4-hydroxylation of 25-hydroxyvitamin D3through CYP3A4 induction in vitro and in vivo: Implications for drug-induced osteomalacia

2013 ◽  
Vol 28 (5) ◽  
pp. 1101-1116 ◽  
Author(s):  
Zhican Wang ◽  
Yvonne S Lin ◽  
Leslie J Dickmann ◽  
Emma-Jane Poulton ◽  
David L Eaton ◽  
...  
Keyword(s):  
Drug Induced ◽  
Cyp3a4 Induction

scholarly journals Regulator of G protein signaling 17 represents a novel target for treating cisplatin induced hearing loss

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Asmita Dhukhwa ◽  
Raheem F. H. Al Aameri ◽  
Sandeep Sheth ◽  
Debashree Mukherjea ◽  
Leonard Rybak ◽  
...  
Keyword(s):  
Hearing Loss ◽  
G Protein ◽  
Protein Interactions ◽  
Cannabinoid Receptor ◽  
Significant Proportion ◽  
G Protein Signaling ◽  
Protein Signaling ◽  
Drug Induced ◽  
Male Wistar Rats

AbstractRegulators of G protein signaling (RGS) accelerate the GTPase activity of G proteins to enable rapid termination of the signals triggered by G protein-coupled receptors (GPCRs). Activation of several GPCRs, including cannabinoid receptor 2 (CB2R) and adenosine A1 receptor (A1AR), protects against noise and drug-induced ototoxicity. One such drug, cisplatin, an anticancer agent used to treat various solid tumors, produces permanent hearing loss in experimental animals and in a high percentage of cancer patients who undergo treatments. In this study we show that cisplatin induces the expression of the RGS17 gene and increases the levels of RGS17 protein which contributes to a significant proportion of the hearing loss. Knockdown of RGS17 suppressed cisplatin-induced hearing loss in male Wistar rats, while overexpression of RGS17 alone produced hearing loss in vivo. Furthermore, RGS17 and CB2R negatively regulate the expression of each other. These data suggest that RGS17 mediates cisplatin ototoxicity by uncoupling cytoprotective GPCRs from their normal G protein interactions, thereby mitigating the otoprotective contributions of endogenous ligands of these receptors. Thus, RGS17 represents a novel mediator of cisplatin ototoxicity and a potential therapeutic target for treating hearing loss.

Imidazolidinyl urea activates mast cells via MRGPRX2 to induce non-histaminergic allergy

2021 ◽  
Author(s):  
Jiapan Gao ◽  
Delu Che ◽  
Xueshan Du ◽  
Yi Zheng ◽  
Huiling Jing ◽  
...  
Keyword(s):  
Contact Dermatitis ◽  
Mast Cells ◽  
Pharmaceutical Products ◽  
Drug Induced ◽  
Inflammatory Infiltration ◽  
Local Inflammatory Response ◽  
Allergic Contact ◽  
G Protein Coupled

Abstract Imidazolidinyl urea (IU) is used as an antimicrobial preservative in cosmetic and pharmaceutical products. IU induces allergic contact dermatitis, however, the mechanism has not yet been elucidated. Mas-related G protein-coupled receptor-X2 (MRGPRX2) triggers drug-induced pseudo-allergic reactions. The aims of this study were to determine whether IU activated mast cells through MRGPRX2 to further trigger contact dermatitis. Wild-type (WT) and KitW-sh/HNihrJaeBsmJNju (MUT) mice were treated with IU to observe its effects on local inflammation and mast cells degranulation in vivo. Laboratory of allergic disease 2 cells were used to detect calcium mobilization and release of inflammatory mediators in vitro. WT mice showed a severe local inflammatory response and contact dermatitis, whereas only slight inflammatory infiltration was observed in MUT mice. Thus, MRGPRX2 mediated the IU-induced activation of mast cells. However, histamine, a typical allergen, was not involved in this process. Tryptase expressed by mast cells was the major non-histaminergic inflammatory mediator of contact dermatitis. IU induced anaphylactic reaction via MRGPRX2 and further triggering non-histaminergic contact dermatitis, which explained why antihistamines are clinically ineffective against some chronic dermatitis.

scholarly journals Comprehensive characterization and quantification of adeno associated vectors by size exclusion chromatography and multi angle light scattering

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nicole L. McIntosh ◽  
Geoffrey Y. Berguig ◽  
Omair A. Karim ◽  
Christa L. Cortesio ◽  
Rolando De Angelis ◽  
...  
Keyword(s):  
Light Scattering ◽  
Size Exclusion Chromatography ◽  
Molar Mass ◽  
Size Exclusion ◽  
Minimal Sample ◽  
Accuracy And Precision ◽  
Vector Genome ◽  
Exclusion Chromatography ◽  
Novel Applications

AbstractAdeno associated virus (AAV) capsids are a leading modality for in vivo gene delivery. Complete and precise characterization of capsid particles, including capsid and vector genome concentration, is necessary to safely and efficaciously dose patients. Size exclusion chromatography (SEC) coupled to multiangle light scattering (MALS) offers a straightforward approach to comprehensively characterize AAV capsids. The current study demonstrates that this method provides detailed AAV characterization information, including but not limited to aggregation profile, size-distribution, capsid content, capsid molar mass, encapsidated DNA molar mass, and total capsid and vector genome titer. Currently, multiple techniques are required to generate this information, with varying accuracy and precision. In the current study, a new series of equations for SEC-MALS are used in tandem with intrinsic properties of the capsids and encapsidated DNA to quantify multiple physical AAV attributes in one 20-min run with minimal sample manipulation, high accuracy, and high precision. These novel applications designate this well-established method as a powerful tool for product development and process analytics in future gene therapy programs.

scholarly journals In Vivo and In Vitro Toxicodynamic Analyses of New Quinolone-and Nonsteroidal Anti-Inflammatory Drug-Induced Effects on the Central Nervous System

1999 ◽  
Vol 43 (5) ◽  
pp. 1091-1097 ◽  
Author(s):  
Hideki Kita ◽  
Hirotami Matsuo ◽  
Hitomi Takanaga ◽  
Junichi Kawakami ◽  
Koujirou Yamamoto ◽  
...  
Keyword(s):  
Brain Tissue ◽  
Threshold Concentration ◽  
Current Response ◽  
Drug Induced ◽  
Inhibition Ratio ◽  
New Quinolones ◽  
The Central Nervous System ◽  
Anti Inflammatory

ABSTRACT We investigated the correlation between an in vivo isobologram based on the concentrations of new quinolones (NQs) in brain tissue and the administration of nonsteroidal anti-inflammatory drugs (NSAIDs) for the occurrence of convulsions in mice and an in vitro isobologram based on the concentrations of both drugs for changes in the γ-aminobutyric acid (GABA)-induced current response in Xenopus oocytes injected with mRNA from mouse brains in the presence of NQs and/or NSAIDs. After the administration of enoxacin (ENX) in the presence or absence of felbinac (FLB), ketoprofen (KTP), or flurbiprofen (FRP), a synergistic effect was observed in the isobologram based on the threshold concentration in brain tissue between mice with convulsions and those without convulsions. The three NSAIDs did not affect the pharmacokinetic behavior of ENX in the brain. However, the ENX-induced inhibition of the GABA response in the GABAA receptor expressed in Xenopus oocytes was enhanced in the presence of the three NSAIDs. The inhibition ratio profiles of the GABA responses for both drugs were analyzed with a newly developed toxicodynamic model. The inhibitory profiles for ENX in the presence of NSAIDs followed the order KTP (1.2 μM) > FRP (0.3 μM) > FLB (0.2 μM). These were 50- to 280-fold smaller than those observed in the absence of NSAIDs. The inhibition ratio (0.01 to 0.02) of the GABAA receptor in the presence of both drugs was well-fitted to the isobologram based on threshold concentrations of both drugs in brain tissue between mice with convulsions and those without convulsions, despite the presence of NSAIDs. In mice with convulsions, the inhibitory profiles of the threshold concentrations of both drugs in brain tissue of mice with convulsions and those without convulsions can be predicted quantitatively by using in vitro GABA response data and toxicodynamic model.

A Useful Diagnostic Method for Drug-induced Pneumonitis

1994 ◽  
Vol 22 (03n04) ◽  
pp. 329-336 ◽  
Author(s):  
Akira Kawasaki ◽  
Yutaka Mizushima ◽  
Hitoshi Kunitani ◽  
Masanobu Kitagawa ◽  
Masashi Kobayashi
Keyword(s):  
Bronchoalveolar Lavage Fluid ◽  
Challenge Test ◽  
Lavage Fluid ◽  
Peripheral Blood Lymphocytes ◽  
Lymphocyte Stimulation Test ◽  
Drug Induced ◽  
Chief Complaints ◽  
History Of ◽  
Chest X Ray

A 51 year-old male was admitted to our hospital with chief complaints of fever, dry cough and dyspnea. Chest X -ray films and his history of taking Chinese medicine for liver dysfunction were suggestive of drug-induced pneumonitis. Lymphocyte stimulation test (LST) to causative Chinese medical drugs of Sho-saiko-to and Dai-saiko-to was negative with peripheral blood lymphocytes (PBL), but was positive with Iymphocytes from bronchoalveolar lavage fluid (BALF). In vivo challenge test for Sho-saiko-to was positive. The LST with BALF-lymphocytes proved to be very useful in making a diagnosis of drug-induced pneumonitis.

Drug-induced liver injury classification model based on in vitro human transcriptomics and in vivo rat clinical chemistry data

2014 ◽  
Vol 2 (4) ◽  
pp. 63-70 ◽  
Author(s):  
Danyel Jennen ◽  
Jan Polman ◽  
Mark Bessem ◽  
Maarten Coonen ◽  
Joost van Delft ◽  
...  
Keyword(s):  
Liver Injury ◽  
Clinical Chemistry ◽  
Classification Model ◽  
Drug Induced ◽  
Drug Induced Liver Injury ◽  
Chemistry Data ◽  
Model Based ◽  
Injury Classification

scholarly journals Drug-Induced Conformational Changes in Multidrug Efflux Transporter AcrB from Haemophilus influenzae

2007 ◽  
Vol 189 (15) ◽  
pp. 5550-5558 ◽  
Author(s):  
Vishakha Dastidar ◽  
Weimin Mao ◽  
Olga Lomovskaya ◽  
Helen I. Zgurskaya
Keyword(s):  
Multidrug Resistance ◽  
Haemophilus Influenzae ◽  
Conformational Changes ◽  
Efflux Transporter ◽  
Multidrug Efflux ◽  
Drug Induced ◽  
Gram Negative ◽  
Membrane Fusion Protein ◽  
Outer Membrane Channel

ABSTRACT In gram-negative bacteria, transporters belonging to the resistance-nodulation-cell division (RND) superfamily of proteins are responsible for intrinsic multidrug resistance. Haemophilus influenzae, a gram-negative pathogen causing respiratory diseases in humans and animals, constitutively produces the multidrug efflux transporter AcrB (AcrBHI). Similar to other RND transporters AcrBHI associates with AcrAHI, the periplasmic membrane fusion protein, and the outer membrane channel TolCHI. Here, we report that AcrABHI confers multidrug resistance when expressed in Escherichia coli and requires for its activity the E. coli TolC (TolCEC) protein. To investigate the intracellular dynamics of AcrABHI, single cysteine mutations were constructed in AcrBHI in positions previously identified as important for substrate recognition. The accessibility of these strategically positioned cysteines to the hydrophilic thiol-reactive fluorophore fluorescein-5-maleimide (FM) was studied in vivo in the presence of various substrates of AcrABHI and in the presence or absence of AcrAHI and TolCEC. We report that the reactivity of specific cysteines with FM is affected by the presence of some but not all substrates. Our results suggest that substrates induce conformational changes in AcrBHI.

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