In vitro P-glycoprotein activity does not completely explain in vivo efficacy of novel centrally effective oxime acetylcholinesterase reactivators

Abstract Recent studies have illustrated the burden Cryptosporidium infection places on the lives of malnourished children and immunocompromised individuals. Treatment options remain limited, and efforts to develop a new therapeutic are currently underway. However, there are unresolved questions about the ideal pharmacokinetic characteristics of new anti-Cryptosporidium therapeutics. Specifically, should drug developers optimize therapeutics and formulations to increase drug exposure in the gastrointestinal lumen, enterocytes, or systemic circulation? Furthermore, how should researchers interpret data suggesting their therapeutic is a drug efflux transporter substrate? In vivo drug transporter–mediated alterations in efficacy are well recognized in multiple disease areas, but the impact of intestinal transporters on therapeutic efficacy against enteric diseases has not been established. Using multiple in vitro models and a mouse model of Cryptosporidium infection, we characterized the effect of P-glycoprotein efflux on bumped kinase inhibitor pharmacokinetics and efficacy. Our results demonstrated P-glycoprotein decreases bumped kinase inhibitor enterocyte exposure, resulting in reduced in vivo efficacy against Cryptosporidium. Furthermore, a hollow fiber model of Cryptosporidium infection replicated the in vivo impact of P-glycoprotein on anti-Cryptosporidium efficacy. In conclusion, when optimizing drug candidates targeting the gastrointestinal epithelium or gastrointestinal epithelial infections, drug developers should consider the adverse impact of active efflux transporters on efficacy.

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Faculty Opinions recommendation of The in vitro mechanisms and in vivo efficacy of intravenous lidocaine on the neuroinflammatory response in acute and chronic pain.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.726025441.793523751 ◽

2016 ◽

Author(s):

Jan Jakobsson

Keyword(s):

Chronic Pain ◽

Intravenous Lidocaine ◽

Neuroinflammatory Response ◽

In Vivo Efficacy

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Intracellular localisation of Mycobacterium tuberculosis affects efficacy of the antibiotic pyrazinamide

Nature Communications ◽

10.1038/s41467-021-24127-3 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Pierre Santucci ◽

Daniel J. Greenwood ◽

Antony Fearns ◽

Kai Chen ◽

Haibo Jiang ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Host Cell ◽

Combination Chemotherapy ◽

In Vitro Activity ◽

In Vivo Efficacy ◽

Human Macrophages ◽

Ion Microscopy ◽

Intracellular Localisation

AbstractTo be effective, chemotherapy against tuberculosis (TB) must kill the intracellular population of the pathogen, Mycobacterium tuberculosis. However, how host cell microenvironments affect antibiotic accumulation and efficacy remains unclear. Here, we use correlative light, electron, and ion microscopy to investigate how various microenvironments within human macrophages affect the activity of pyrazinamide (PZA), a key antibiotic against TB. We show that PZA accumulates heterogeneously among individual bacteria in multiple host cell environments. Crucially, PZA accumulation and efficacy is maximal within acidified phagosomes. Bedaquiline, another antibiotic commonly used in combined TB therapy, enhances PZA accumulation via a host cell-mediated mechanism. Thus, intracellular localisation and specific microenvironments affect PZA accumulation and efficacy. Our results may explain the potent in vivo efficacy of PZA, compared to its modest in vitro activity, and its critical contribution to TB combination chemotherapy.

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P074 In vitro and in vivo efficacy of linezolid on Treponema pallidum, the syphilis agent

10.1136/sextrans-2021-sti.208 ◽

2021 ◽

Author(s):

L Giacani ◽

A Haynes ◽

M Vall Mayans ◽

M Ubals Cazorla ◽

C Nieto ◽

...

Keyword(s):

Treponema Pallidum ◽

In Vivo Efficacy

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Efficacy of a novel lantibiotic, CMB001, against MRSA

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/dkab040 ◽

2021 ◽

Author(s):

Jerzy Karczewski ◽

Christine M Brown ◽

Yukari Maezato ◽

Stephen P Krasucki ◽

Stephen J Streatfield

Keyword(s):

Antibacterial Activity ◽

Pharmacokinetic Analysis ◽

Maximum Tolerable Dose ◽

In Vivo Efficacy ◽

Clostridioides Difficile ◽

Alternative Treatment Option ◽

Significant Damage ◽

Tolerable Dose

Abstract Objectives To evaluate the efficacy of a novel lantibiotic, CMB001, against MRSA biofilms in vitro and in an in vivo experimental model of bacterial infection. Methods Antibacterial activity of CMB001 was measured in vitro after its exposure to whole blood or to platelet-poor plasma. In vitro efficacy of CMB001 against a Staphylococcus aureus biofilm was studied using scanning electron microscopy. The maximum tolerable dose in mice was determined and a preliminary pharmacokinetic analysis for CMB001 was performed in mice. In vivo efficacy was evaluated in a neutropenic mouse thigh model of infection. Results CMB001 maintained its antibacterial activity in the presence of blood or plasma for up to 24 h at 37°C. CMB001 efficiently killed S. aureus within the biofilm by causing significant damage to the bacterial cell wall. The maximum tolerable dose in mice was established to be 10 mg/kg and could be increased to 30 mg/kg in mice pretreated with antihistamines. In neutropenic mice infected with MRSA, treatment with CMB001 reduced the bacterial burden with an efficacy equivalent to that of vancomycin. Conclusions CMB001 offers potential as an alternative treatment option to combat MRSA. It will be of interest to evaluate the in vivo efficacy of CMB001 against infections caused by other pathogens, including Clostridioides difficile and Acinetobacter baumannii, and to expand its pharmacokinetic/pharmacodynamic parameters and safety profile.

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Overcoming multidrug-resistance in vitro and in vivo using the novel P-glycoprotein inhibitor 1416

Bioscience Reports ◽

10.1042/bsr20120020 ◽

2012 ◽

Vol 32 (6) ◽

pp. 559-566 ◽

Cited By ~ 19

Author(s):

Yan Xu ◽

Feng Zhi ◽

Guangming Xu ◽

Xiaolei Tang ◽

Sheng Lu ◽

...

Keyword(s):

Multidrug Resistance ◽

Cancer Chemotherapy ◽

Antitumour Activity ◽

Multidrug Resistant ◽

The Novel ◽

Mice Model ◽

P Glycoprotein ◽

Channel Currents

MDR (multidrug-resistance) represents a major obstacle to successful cancer chemotherapy and is usually accomplished by overexpression of P-gp (P-glycoprotein). Much effort has been devoted to developing P-gp inhibitors to modulate MDR. However, none of the inhibitors on the market have been successful. 1416 [1-(2,6-dimethylphenoxy)-2-(3,4-dimethoxyphenylethylamino)propane hydrochloride (phenoprolamine hydrochloride)] is a new VER (verapamil) analogue with a higher IC50 for blocking calcium channel currents than VER. In the present paper, we examined the inhibition effect of 1416 on P-gp both in vitro and in vivo. 1416 significantly enhanced cytotoxicity of VBL (vinblastine) in P-gp-overexpressed human multidrug-resistant K562/ADM (adriamycin) and KBV cells, but had no such effect on the parent K562 and KB cells. The MDR-modulating function of 1416 was further confirmed by increasing intracellular Rh123 (rhodanmine123) content in MDR cells. Human K562/ADM xenograft-nude mice model verified that 1416 potentiates the antitumour activity of VBL in vivo. RT-PCR (reverse transcriptase-PCR) and FACS analysis demonstrated that the expression of MDR1/P-gp was not affected by 1416 treatment. All these observations suggest that 1416 could be a promising agent for overcoming MDR in cancer chemotherapy.

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In Vitro and in Vivo Evaluation of Phenylbutenoid Dimers as Inhibitors of P-Glycoprotein

Journal of Natural Products ◽

10.1021/np4004917 ◽

2013 ◽

Vol 76 (12) ◽

pp. 2277-2281 ◽

Cited By ~ 5

Author(s):

Song Wha Chae ◽

Ah-Reum Han ◽

Jung Hyun Park ◽

Jeong Yeon Rhie ◽

Hee-Jong Lim ◽

...

Keyword(s):

In Vivo Evaluation ◽

P Glycoprotein

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Upregulations of Clcn3 and P-Gp Provoked by Lens Osmotic Expansion in Rat Galactosemic Cataract

Journal of Diabetes Research ◽

10.1155/2017/3472735 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8

Author(s):

Lixia Ji ◽

Lixia Cheng ◽

Zhihong Yang

Keyword(s):

Osmotic Stress ◽

Early Stage ◽

Lens Epithelial Cells ◽

Anterior Capsule ◽

Glycoprotein P ◽

Protein Levels ◽

P Glycoprotein ◽

Sugar Cataract

Objective.Lens osmotic expansion, provoked by overactivated aldose reductase (AR), is the most essential event of sugar cataract. Chloride channel 3 (Clcn3) is a volume-sensitive channel, mainly participating in the regulation of cell fundamental volume, and P-glycoprotein (P-gp) acts as its modulator. We aim to study whether P-gp and Clcn3 are involved in lens osmotic expansion of galactosemic cataract.Methods and Results.In vitro, lens epithelial cells (LECs) were primarily cultured in gradient galactose medium (10–60 mM), more and more vacuoles appeared in LEC cytoplasm, and mRNA and protein levels of AR, P-gp, and Clcn3 were synchronously upregulated along with the increase of galactose concentration. In vivo, we focused on the early stage of rat galactosemic cataract, amount of vacuoles arose from equatorial area and scattered to the whole anterior capsule of lenses from the 3rd day to the 9th day, and mRNA and protein levels of P-gp and Clcn3 reached the peak around the 9th or 12th day.Conclusion. Galactosemia caused the osmotic stress in lenses; it also markedly leads to the upregulations of AR, P-gp, and Clcn3 in LECs, together resulting in obvious osmotic expansion in vitro and in vivo.

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