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Doklady. Biochemistry and Biophysics Dec 2022In the study on cells of the Caco-2 line, the affiliation of malondialdehyde (MDA) to modulators and substrates of P-glycoprotein (Pgp) was assessed, and the biological...
In the study on cells of the Caco-2 line, the affiliation of malondialdehyde (MDA) to modulators and substrates of P-glycoprotein (Pgp) was assessed, and the biological role of Pgp in conditions of oxidative stress (OS) was studied. MDA was used at concentrations of 10, 50, 100, and 150 μM; OS was simulated by incubation with hydrogen peroxide (HO) at concentrations of 0.1-100 μM for 24 h. The relative amount of Pgp was evaluated by the Western blot hybridization, and the activity was estimated by the transport of its substrate fexofenadine (HPLC with UV detection, HPLC MS/MS). In this study, it was shown that MDA at concentrations of 10 and 50 μM and exposure duration of 24 h increases the relative amount and activity of Pgp by acting through CAR and PXR, and MDA can be transported by Pgp. The induction of Pgp under the action of MDA during the development of OS can have a protective significance, ensuring the removal of the peroxidation product from cells into the extracellular space and thereby increasing the viability of cells.
Topics: Humans; ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily B, Member 1; Caco-2 Cells; Hydrogen Peroxide; Tandem Mass Spectrometry; Malondialdehyde
PubMed: 36786982
DOI: 10.1134/S1607672922060096 -
Journal of Medicinal Chemistry Dec 2019Overexpression of ABC transporters like P-glycoprotein (P-gp) has been correlated with resistances in cancer chemotherapy. Intensive efforts to identify P-gp inhibitors...
Overexpression of ABC transporters like P-glycoprotein (P-gp) has been correlated with resistances in cancer chemotherapy. Intensive efforts to identify P-gp inhibitors for use in combination therapy have not led to clinically approved inhibitors to date. Here, we describe computational approaches combined with structure-based design to improve the characteristics of a P-gp inhibitor previously identified by us. This hit compound represents a novel class of P-gp inhibitors that specifically targets and inhibits P-gp ATP hydrolysis while not being transported by the pump. We describe here a new program for virtual chemical synthesis and computational assessment, ChemGen, to produce hit compound variants with improved binding characteristics. The chemical syntheses of several variants, efficacy in reversing multidrug resistance in cell culture, and biochemical assessment of the inhibition mechanism are described. The usefulness of the computational predictions of binding characteristics of the inhibitor variants is discussed and compared to more traditional structure-based approaches.
Topics: ATP Binding Cassette Transporter, Subfamily B, Member 1; Antineoplastic Agents; Binding Sites; Cell Line, Tumor; Cell Survival; Computer-Aided Design; Dose-Response Relationship, Drug; Drug Delivery Systems; Fluoresceins; Humans; Models, Molecular; Molecular Structure; Paclitaxel; Protein Binding; Protein Conformation; Structure-Activity Relationship
PubMed: 31702922
DOI: 10.1021/acs.jmedchem.9b00966 -
Marine Drugs Sep 2022N-methylpretrichodermamide B (NB) is a biologically active epidithiodiketopiperazine isolated from several strains of the algae-derived fungus sp. Recently, we reported...
N-methylpretrichodermamide B (NB) is a biologically active epidithiodiketopiperazine isolated from several strains of the algae-derived fungus sp. Recently, we reported the first data on its activity in human cancer cells lines in vitro. Here, we investigated the activity, selectivity, and mechanism of action of NB in human prostate cancer cell lines, including drug-resistant subtypes. NB did not reveal cross-resistance to docetaxel in the PC3-DR cell line model and was highly active in hormone-independent 22Rv1 cells. NB-induced cell death was stipulated by externalization of phosphatidylserine and activation of caspase-3. Moreover, inhibition of caspase activity by z-VAD(OMe)-fmk did not affect NB cytotoxicity, suggesting a caspase-independent cell death induced by NB. The compound has a moderate p-glycoprotein (p-gp) substrate-like affinity and can simultaneously inhibit p-gp at nanomolar concentrations. Therefore, NB resensitized p-gp-overexpressing PC3-DR cells to docetaxel. A kinome profiling of the NB-treated cells revealed, among other things, an induction of mitogen-activated protein kinases JNK1/2 and p38. Further functional analysis confirmed an activation of both kinases and indicated a prosurvival role of this biological event in the cellular response to the treatment. Overall, NB holds promising anticancer potential and further structure-activity relationship studies and structural optimization are needed in order to improve its biological properties.
Topics: Humans; Male; Antineoplastic Agents; Apoptosis; ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily B, Member 1; Caspase 3; Cell Line, Tumor; Docetaxel; Drug Resistance, Neoplasm; Hormones; Phosphatidylserines; Prostatic Neoplasms
PubMed: 36286421
DOI: 10.3390/md20100597 -
Scientific Reports Sep 2020Malpighian tubules, analogous to vertebrate nephrons, play a key role in insect osmoregulation and detoxification. Tubules can become infected with a protozoan,...
Malpighian tubules, analogous to vertebrate nephrons, play a key role in insect osmoregulation and detoxification. Tubules can become infected with a protozoan, Malpighamoeba, which damages their epithelial cells, potentially compromising their function. Here we used a modified Ramsay assay to quantify the impact of Malpighamoeba infection on fluid secretion and P-glycoprotein-dependent detoxification by desert locust Malpighian tubules. Infected tubules have a greater surface area and a higher fluid secretion rate than uninfected tubules. Infection also impairs P-glycoprotein-dependent detoxification by reducing the net rhodamine extrusion per surface area. However, due to the increased surface area and fluid secretion rate, infected tubules have similar total net extrusion per tubule to uninfected tubules. Increased fluid secretion rate of infected tubules likely exposes locusts to greater water stress and increased energy costs. Coupled with reduced efficiency of P-glycoprotein detoxification per surface area, Malpighamoeba infection is likely to reduce insect survival in natural environments.
Topics: ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily B, Member 1; Amebiasis; Amoebida; Animals; Biological Transport; Bodily Secretions; Epithelial Cells; Grasshoppers; Infections; Malpighian Tubules; Water-Electrolyte Balance
PubMed: 32994425
DOI: 10.1038/s41598-020-72598-z -
Drug Metabolism and Pharmacokinetics Apr 2020Effect of long-term treatment with cigarette smoke extract (CSE) on the function and expression of P-glycoprotein (P-gp) in lung alveolar epithelial cells was examined...
Effect of long-term treatment with cigarette smoke extract (CSE) on the function and expression of P-glycoprotein (P-gp) in lung alveolar epithelial cells was examined using A549/P-gp cell line expressing P-gp. CSE treatment suppressed P-gp activity in a concentration- and treatment time-dependent manner. The suppression of P-gp activity by CSE was irreversible for at least 96 h after removal of CSE. In addition, CSE treatment suppressed the expression of P-gp mRNA and protein. In order to understand the mechanisms underlying P-gp suppression by CSE, the role of reactive oxygen species (ROS) was examined. CSE treatment increased intracellular ROS level, and suppressed catalase activity. α-Tocopherol suppressed ROS production by CSE, and ameliorated the suppression of P-gp activity by CSE, suggesting that ROS is involved in CSE-induced suppression of P-gp. The role of intracellular signaling pathways such as the nuclear factor κB and mitogen-activated protein kinase pathways was also examined. Among these pathways, the involvement of extracellular signal-regulated kinase (ERK) pathway was suggested. Taken together, long-term CSE treatment may suppress P-gp via modulation of ROS level and ERK pathway in alveolar epithelial cells.
Topics: A549 Cells; ATP Binding Cassette Transporter, Subfamily B, Member 1; Epithelial Cells; Humans; Lung Neoplasms; Mitogen-Activated Protein Kinases; Plant Extracts; Reactive Oxygen Species; Signal Transduction; Smoke
PubMed: 32037157
DOI: 10.1016/j.dmpk.2019.12.001 -
Medicinal Research Reviews Jan 2021Multidrug resistance (MDR) remains one of the major impediments for efficacious cancer chemotherapy. Increased efflux of multiple chemotherapeutic drugs by transmembrane... (Review)
Review
Multidrug resistance (MDR) remains one of the major impediments for efficacious cancer chemotherapy. Increased efflux of multiple chemotherapeutic drugs by transmembrane ATP-binding cassette (ABC) transporter superfamily is considered one of the primary causes for cancer MDR, in which the role of P-glycoprotein (P-gp/ABCB1) has been most well-established. The clinical co-administration of P-gp drug efflux inhibitors, in combination with anticancer drugs which are P-gp transport substrates, was considered to be a treatment modality to surmount MDR in anticancer therapy by blocking P-gp-mediated multidrug efflux. Extensive attempts have been carried out to screen for sets of nontoxic, selective, and efficacious P-gp efflux inhibitors. In this review, we highlight the recent achievements in drug design, characterization, structure-activity relationship (SAR) studies, and mechanisms of action of the newly synthetic, potent small molecules P-gp inhibitors in the past 5 years. The development of P-gp inhibitors will increase our knowledge of the mechanisms and functions of P-gp-mediated drug efflux which will benefit drug discovery and clinical cancer therapeutics where P-gp transporter overexpression has been implicated in MDR.
Topics: ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily B, Member 1; Antineoplastic Agents; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Humans; Neoplasms
PubMed: 33047304
DOI: 10.1002/med.21739 -
Clinical Pharmacology and Therapeutics Jan 2021There is an increasing interest in transporter induction (i.e., decreased systemic drug exposure due to increased efflux-limited absorption or transporter-mediated... (Review)
Review
There is an increasing interest in transporter induction (i.e., decreased systemic drug exposure due to increased efflux-limited absorption or transporter-mediated clearance) as a mechanism of drug-drug interactions (DDIs), although evidence of clinical relevance is still evolving. Intestinal P-glycoprotein (P-gp) and hepatic organic anion transporting polypeptides 1B (OATP1B) can be important determinants of drug absorption and disposition, as well as targets for DDIs. Current data indicate that intestinal P-gp protein levels can be induced up to threefold to fourfold in humans primarily with pregnane X receptor (PXR) activators, and that this induction can decrease the systemic exposure of drugs with P-gp efflux-limited absorption (e.g., ≤ 67% decrease in the exposure of total dabigatran following rifampin multiple oral dosing). Evaluation of the clinical relevance of P-gp induction as a DDI mechanism must consider the induction potential of the perpetrator drug for P-gp and attenuation of exposure of the victim drug in the context of its therapeutic window. Practical drug development recommendations are provided herein. Reports are contradictory on OATP1B induction by PXR activators in human hepatocytes and liver biopsies. Some clinical investigations demonstrated that rifampin pretreatment decreased exposure of OATP1B substrates, while other studies found no differences, and the potential involvement of other mechanisms in these observed DDIs cannot be definitively ruled out. Thus, further studies are needed to understand hepatic OATP1B induction and potential involvement of other mechanisms contributing to reduced exposure of OATP1B substrates. This review critically summarizes the state-of-the-art on intestinal P-gp and hepatic OATP1B induction, and highlights implications for drug development.
Topics: ATP Binding Cassette Transporter, Subfamily B, Member 1; Biological Transport; Drug Development; Hepatocytes; Humans; Intestines; Liver; Liver-Specific Organic Anion Transporter 1; Membrane Transport Proteins
PubMed: 32460379
DOI: 10.1002/cpt.1916 -
Journal of Natural Products Mar 2022Photoaffinity labeling approaches have historically been used in pharmacology to identify molecular targets. This methodology has played a pivotal role in identifying... (Review)
Review
Photoaffinity labeling approaches have historically been used in pharmacology to identify molecular targets. This methodology has played a pivotal role in identifying drug-binding domains and searching for novel compounds that may interact at these domains. In this review we focus on studies of microtubule stabilizing agents of natural product origin, specifically taxol (paclitaxel). Taxol and other microtubule interacting agents bind to both P-glycoprotein (ABCB1), a drug efflux pump that reduces intracellular drug accumulation, and the tubulin/microtubule system. Both binding relationships modulate drug efficacy and are of immense interest to basic and translational scientists, primarily because of their association with drug resistance for this class of molecules. We present this body of work and acknowledge its value as fundamental to understanding the mechanisms of taxol and elucidation of the taxol pharmacophore. Furthermore, we highlight the ability to multiplex photoaffinity approaches with other technologies to further enhance our understanding of pharmacologic interactions at an atomic level. Thus, photoaffinity approaches offer a relatively inexpensive and robust technique that will continue to play an important role in drug discovery for the foreseeable future.
Topics: ATP Binding Cassette Transporter, Subfamily B, Member 1; Excipients; Microtubules; Paclitaxel; Tubulin
PubMed: 35240035
DOI: 10.1021/acs.jnatprod.2c00106 -
Benzophenone Sulfonamide Derivatives as Interacting Partners and Inhibitors of Human P-glycoprotein.Anti-cancer Agents in Medicinal... 2020Human P-glycoprotein (P-gp) is a transmembrane protein that belongs to the ATPBinding Cassette (ABC) transporters family. Physiologically, it exports toxins out of the...
BACKGROUND
Human P-glycoprotein (P-gp) is a transmembrane protein that belongs to the ATPBinding Cassette (ABC) transporters family. Physiologically, it exports toxins out of the cell, however, its overexpression leads to the phenomena of Multidrug-Resistance (MDR) by exporting a diverse range of compounds, which are structurally and chemically different from each other, thus creating a hurdle in the treatment of various diseases including cancer. The current study was designed to screen benzophenone sulfonamide derivatives as a class of inhibitors and potential anticancer agents for P-gp.
METHODS
A total number of 15 compounds were evaluated. These compounds were screened in daunorubicin efflux inhibition assays using CCRF-CEM Vcr1000 cell line that overexpressed human P-gp. Cytotoxicity assay was also performed for active compounds 11, 14, and 13. These scaffolds were then docked in the homology model of human P-gp using mouse P-gp as a template (PDB ID: 4MIM) and the recently published Cryo Electron Microscopy (CEM) structure of human mouse chimeric P-gp to find their interactions with specified residues in the binding pocket. Analysis was performed using Labview VI and Graph pad prism version 5.0.
RESULTS
Results revealed the potency of all these compounds in low nanomolar range whereas, compound 14 was found to be most active with IC50 value of 18.35nM±4.90 followed by 11 and 13 having IC50 values of 30.66nM±5.49 and 46.12nM±3.06, respectively. Moreover, IC50 values calculated for 14, 11 and 13 in cytotoxicity assay were found to be 22.97μM±0.026, 583.1μM±0.027 and 117.8μM±0.062, respectively. Docking results showed the interaction of these scaffolds in transmembrane helices (TM) where Tyr307, Tyr310, Tyr953, Met986 and Gln946 were found to be the major interaction partners, thus they might play a significant role in the transport of these scaffolds.
CONCLUSION
Benzophenone sulfonamide derivatives showed IC50 values in low nanomolar range comparable to the standard inhibitor Verapamil, therefore they can be good inhibitors of P-gp and can serve as anticancer agents. Also, they have shown interactions in the transmembrane region sharing the same binding region of verapamil and zosuquidar.
Topics: ATP Binding Cassette Transporter, Subfamily B, Member 1; Antineoplastic Agents; Benzophenones; Cell Line, Tumor; Cell Proliferation; Cell Survival; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Humans; Molecular Docking Simulation; Molecular Structure; Structure-Activity Relationship; Sulfonamides
PubMed: 32416700
DOI: 10.2174/1871520620666200516144403 -
Molecules (Basel, Switzerland) Nov 2023P-glycoprotein (P-gp) is a crucial membrane transporter situated on the cell's apical surface, being responsible for eliminating xenobiotics and endobiotics. P-gp... (Review)
Review
P-glycoprotein (P-gp) is a crucial membrane transporter situated on the cell's apical surface, being responsible for eliminating xenobiotics and endobiotics. P-gp modulators are compounds that can directly or indirectly affect this protein, leading to changes in its expression and function. These modulators can act as inhibitors, inducers, or activators, potentially causing drug-drug interactions (DDIs). This comprehensive review explores diverse models and techniques used to assess drug-induced P-gp modulation. We cover several approaches, including , , , and methods, with their respective strengths and limitations. Additionally, we explore the therapeutic implications of DDIs involving P-gp, with a special focus on the renal and intestinal elimination of P-gp substrates. This involves enhancing the removal of toxic substances from proximal tubular epithelial cells into the urine or increasing the transport of compounds from enterocytes into the intestinal lumen, thereby facilitating their excretion in the feces. A better understanding of these interactions, and of the distinct techniques applied for their study, will be of utmost importance for optimizing drug therapy, consequently minimizing drug-induced adverse and toxic effects.
Topics: ATP Binding Cassette Transporter, Subfamily B, Member 1; Membrane Transport Proteins; ATP Binding Cassette Transporter, Subfamily B; Kidney; Drug Interactions
PubMed: 38005253
DOI: 10.3390/molecules28227532