Determination of efflux activity in Enterococci by Hoechst accumulation assay and the role of zinc oxide nanoparticles in inhibition of this activity

Sobhanipoor, Mohammad Hossein; Ahmadrajabi, Roya; Hosseini-Nave, Hossein; Saffari, Fereshteh

doi:10.1186/s12866-022-02595-x

Cited by 4 publications

(1 citation statement)

References 26 publications

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“…This is a significant challenge in cancer therapy and it is imperative to conduct a detailed study of its functionality. To assess the functionality of efflux pumps in a cell or tissue sample, researchers can expose the cells to Hoechst dye with or without efflux pump inhibitors [114]. If the cells have active efflux pumps, they will pump out the dye, resulting in reduced intracellular Hoechst staining, and weaker fluorescence.…”

Section: Efflux Transporters In Chemoresistant Bc Cellsmentioning

confidence: 99%

Breast Cancer Chemoresistance: Insights into the Regulatory Role of lncRNA

Ahmadpour,

Orre,

Bertevello

et al. 2023

IJMS

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Long noncoding RNAs (lncRNAs) are a subclass of noncoding RNAs composed of more than 200 nucleotides without the ability to encode functional proteins. Given their involvement in critical cellular processes such as gene expression regulation, transcription, and translation, lncRNAs play a significant role in organism homeostasis. Breast cancer (BC) is the second most common cancer worldwide and evidence has shown a relationship between aberrant lncRNA expression and BC development. One of the main obstacles in BC control is multidrug chemoresistance, which is associated with the deregulation of multiple mechanisms such as efflux transporter activity, mitochondrial metabolism reprogramming, and epigenetic regulation as well as apoptosis and autophagy. Studies have shown the involvement of a large number of lncRNAs in the regulation of such pathways. However, the underlying mechanism is not clearly elucidated. In this review, we present the principal mechanisms associated with BC chemoresistance that can be directly or indirectly regulated by lncRNA, highlighting the importance of lncRNA in controlling BC chemoresistance. Understanding these mechanisms in deep detail may interest the clinical outcome of BC patients and could be used as therapeutic targets to overcome BC therapy resistance.

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Section: Efflux Transporters In Chemoresistant Bc Cellsmentioning

confidence: 99%

Breast Cancer Chemoresistance: Insights into the Regulatory Role of lncRNA

Ahmadpour,

Orre,

Bertevello

et al. 2023

IJMS

View full text Add to dashboard Cite

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Highly Effective Biocides against Pseudomonas aeruginosa Reveal New Mechanistic Insights Across Gram-Negative Bacteria

Sanchez,

Vargas-Cuebas,

Michaud

et al. 2024

ACS Infect. Dis.

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Pseudomonas aeruginosa is a major nosocomial pathogen that persists in healthcare settings despite rigorous disinfection protocols due to intrinsic mechanisms conferring resistance. We sought to systematically assess cationic biocide efficacy against this pathogen using a panel of multidrug-resistant P. aeruginosa clinical isolates. Our studies revealed widespread resistance to commercial cationic disinfectants that are the current standard of care, raising concerns about their efficacy. To address this shortcoming, we highlight a new class of quaternary phosphonium compounds that are highly effective against all members of the panel. To understand the difference in efficacy, mechanism of action studies were carried out, which identified a discrete inner-membrane selective target. Resistance selection studies implicated the SmvRA efflux system (a transcriptionally regulated, inner membrane-associated efflux system) as a major determinant of resistance. This system is also implicated in resistance to two commercial bolaamphiphile antiseptics, octenidine and chlorhexidine, which was further validated herein. In sum, this work highlights, for the first time, a discrete inner-membrane specific mechanism for the bolaamphiphile class of disinfectants that contrasts with the prevailing model of indiscriminate membrane interactions of commercial amphiphiles paving the way for future innovations in disinfectant research.

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Coassembly of Cell-Penetrating Peptide Octaarginine with Acetazolamide: Emergent Interactions with E. coli

Choubey,

Chatterjee,

Pandey

et al. 2024

ACS Omega

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The investigation of established pharmaceutical agents for recalibrating usage strongly supplements new drug development. In this work, we have prepared coassembled complexes of acetazolamide (AZM) with the cationic peptide octaarginine (R8) in an attempt to enhance its potency and scope of use. R8 and AZM in different weight ratios coassemble into remarkable nano-and microstructures such as ribbons, sheets, and stick-like structures. A combination of FTIR, XRD, SEM, and DSC has been used to characterize the R8:AZM coassemblies. The sulfonamide SO 2 and NH 2 groups of AZM are associated with the guanidinium amine, free amine, and terminal carbonyl groups of R8 resulting in distinctive topologies. Treatment of Escherichia coli with the complexes results in a distinctive pattern of membrane disruption and pore formation. The R8:AZM coassemblies inhibit carbonic anhydrase and E. coli growth with greater efficiency compared to bare AZM. The 1:5 w/w complex leads to pronounced outer and inner membrane rupture and significantly restricts glucose uptake by E. coli. The ability of R8 and AZM to coassemble into a distinctive set of structures based solely on differences in their relative proportions and their engagement with E. coli as more than the sum of their parts are novel facets of R8 and AZM behavior and underscore a straightforward and elegant approach for enhancing the scope of use of small molecule drugs.

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Determination of efflux activity in Enterococci by Hoechst accumulation assay and the role of zinc oxide nanoparticles in inhibition of this activity

Cited by 4 publications

References 26 publications

Breast Cancer Chemoresistance: Insights into the Regulatory Role of lncRNA

Breast Cancer Chemoresistance: Insights into the Regulatory Role of lncRNA

Highly Effective Biocides against Pseudomonas aeruginosa Reveal New Mechanistic Insights Across Gram-Negative Bacteria

Coassembly of Cell-Penetrating Peptide Octaarginine with Acetazolamide: Emergent Interactions with E. coli

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