The MDR1 transporter mediated efflux of different xenobiotics out of the cells serves as the most important mechanisms of the multidrug resistance in cancer cells, thus inhibition of the MDR1 transporter may increase the efficiency of anticancer drugs in the therapy. Here we describe some new phenothiazine derivatives, which possess strong in vitro MDR1 inhibitory activity. The effectiveness of the compounds on the MDR1 mediated calcein-AM efflux, ATPase activity, and colchicine resistance was proven by microplate assays and flow cytometry using recombinant and control cell lines. Some of these derivatives were more active than verapamil and one of them was at least as active as cyclosporin A. According to our results the new structural elements built in these phenothiazine type compounds increased their MDR1 inhibitory activity, which may serve as a basis of the development of an effective MDR1 inhibitor drug.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbrc.2006.05.058DOI Listing

Publication Analysis

Top Keywords

mdr1 transporter
12
inhibition mdr1
8
phenothiazine derivatives
8
mdr1 inhibitory
8
inhibitory activity
8
mdr1
6
transporter phenothiazine
4
derivatives mdr1
4
transporter mediated
4
mediated efflux
4

Similar Publications

Human organotypic colon in vitro microtissue: unveiling a new window into colonic drug disposition.

Eur J Pharm Sci

January 2025

Preclinical Sciences & Translational Safety, Janssen R&D, Turnhoutseweg 30, 2340, Beerse, Belgium. Electronic address:

The purpose of this study was to evaluate EpiColon, a novel human organotypic 3D colon microtissue prototype, developed to assess colonic drug disposition, with a particular focus on permeability ranking, and compare its performance to Caco-2 monolayers. EpiColon was characterized for barrier function using transepithelial electrical resistance (TEER), morphology via histology and immunohistochemistry, and functionality through drug transport studies measuring apparent permeability (P). Cutoff thresholds for the permeability of FITC-dextran 4 kDa (FD4), FITC-dextran 10 kDa (FD10S), and [C]mannitol were established to monitor microtissue integrity.

View Article and Find Full Text PDF

Objective: This study aimed to investigate the synergistic effects of the chemotherapy drug Carfilzomib (CFZ) and Pistachio hull extract on the SK-BR3 breast cancer cell line.

Methods: In this experimental study, we evaluated the effect of Pistachio hull extract and CFZ as standalone treatments on cell viability using the MTT assay at 24- and 48-hours post-treatment. Following this, we conducted combination therapy analyses to assess the potential synergistic relationship between Pistachio hull extract and CFZ after 24- and 48-hours of treatment on both the SK-BR3 breast cancer cell line and the MCF10A normal cell line.

View Article and Find Full Text PDF

Access of drugs to the central nervous system is limited by the blood-brain barrier, and this in turn affects drug efficacy/toxicity. To date, most drug discovery optimization paradigms have relied heavily on in vitro transporter assays and preclinical species pharmacokinetic evaluation to provide a qualitative assessment of human brain penetration. Because of the lack of human brain pharmacokinetic data, mechanistic models for preclinical species, combined with in vitro and in silico data, are useful for translation to human.

View Article and Find Full Text PDF

ABCB1 is a broad-spectrum efflux pump central to cellular drug handling and multidrug resistance in humans. However, how it is able to recognize and transport a wide range of diverse substrates remains poorly understood. Here we present cryo-EM structures of lipid-embedded human ABCB1 in conformationally distinct apo-, substrate-bound, inhibitor-bound, and nucleotide-trapped states at 3.

View Article and Find Full Text PDF

Low prevalence of copy number variation in pfmdr1 and pfpm2 in Plasmodium falciparum isolates from southern Angola.

Malar J

January 2025

Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, 1349-008, Lisbon, Portugal.

Background: Malaria is the parasitic disease with the highest global morbidity and mortality. According to estimates from the World Health Organization (WHO), there were around 249 million cases in 2022, with 3.4% occurring in Angola.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!