1
|
Mensah GAK, Schaefer KG, Roberts AG, King GM, Bartlett MG. Probing the Mechanisms Underlying the Transport of the Vinca Alkaloids by P-glycoprotein. J Pharm Sci 2024; 113:1960-1974. [PMID: 38527618 DOI: 10.1016/j.xphs.2024.03.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 03/18/2024] [Accepted: 03/18/2024] [Indexed: 03/27/2024]
Abstract
The efficacy of many cancer drugs is hindered by P-glycoprotein (Pgp), a cellular pump that removes drugs from cells. To improve chemotherapy, drugs capable of evading Pgp must be developed. Despite similarities in structure, vinca alkaloids (VAs) show disparate Pgp-mediated efflux ratios. ATPase activity and binding affinity studies show at least two binding sites for the VAs: high- and low-affinity sites that stimulate and inhibit the ATPase activity rate, respectively. The affinity for ATP from the ATPase kinetics curve for vinblastine (VBL) at the high-affinity site was 2- and 9-fold higher than vinorelbine (VRL) and vincristine (VCR), respectively. Conversely, VBL had the highest Km (ATP) for the low-affinity site. The dissociation constants (KDs) determined by protein fluorescence quenching were in the order VBL < VRL< VCR. The order of the KDs was reversed at higher substrate concentrations. Acrylamide quenching of protein fluorescence indicate that the VAs, either at 10 µM or 150 µM, predominantly maintain Pgp in an open-outward conformation. When 3.2 mM AMPPNP was present, 10 µM of either VBL, VRL, or VCR cause Pgp to shift to an open-outward conformation, while 150 µM of the VAs shifted the conformation of Pgp to an intermediate orientation, between opened inward and open-outward. However, the conformational shift induced by saturating AMPPNP and VCR condition was less than either VBL or VRL in the presence of AMPPNP. At 150 µM, atomic force microscopy (AFM) revealed that the VAs shift Pgp population to a predominantly open-inward conformation. Additionally, STDD NMR studies revealed comparable groups in VBL, VRL, and VCR are in contact with the protein during binding. Our results, when coupled with VAs-microtubule structure-activity relationship studies, could lay the foundation for developing next-generation VAs that are effective as anti-tumor agents. A model that illustrates the intricate process of Pgp-mediated transport of the VAs is presented.
Collapse
Affiliation(s)
- Gershon A K Mensah
- Department of Pharmaceutical and Biomedical Science, University of Georgia, Athens, GA 30602, USA
| | - Katherine G Schaefer
- Department of Physics and Astronomy, University of Missouri, Columbia, MO 65211, USA
| | - Arthur G Roberts
- Department of Pharmaceutical and Biomedical Science, University of Georgia, Athens, GA 30602, USA.
| | - Gavin M King
- Department of Physics and Astronomy, University of Missouri, Columbia, MO 65211, USA; Joint with Biochemistry, University of Missouri, Columbia, MO 65211, USA.
| | - Michael G Bartlett
- Department of Pharmaceutical and Biomedical Science, University of Georgia, Athens, GA 30602, USA.
| |
Collapse
|
2
|
Nguyen PH, Cui S, Kozarich AM, Rautio A, Roberts AG, Xiong MP. Utilizing surface plasmon resonance as a novel method for monitoring in-vitro P-glycoprotein efflux. FRONTIERS IN BIOPHYSICS 2024; 2:1367511. [PMID: 38645731 PMCID: PMC11027885 DOI: 10.3389/frbis.2024.1367511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
P-glycoprotein (Pgp) is known for its dichotomous roles as both a safeguarding efflux transporter against xenobiotics and as a catalyst for multidrug resistance. Given the susceptibility of numerous therapeutic compounds to Pgp-mediated resistance, compliance with Food and Drug Administration (FDA) guidelines mandates an in-depth in vitro transport assay during drug development. This study introduces an innovative transport assay that aligns with these regulatory imperatives but also addresses limitations in the currently established techniques. Using Pgp-reconstituted liposomes and employing surface plasmon resonance (SPR), this study developed a distinct method of measuring the relative transport rates of Pgp substrates in a controlled microenvironment. The Pgp substrates selected for this study-quinidine, methadone, and desipramine-resulted in transport ratios that corroborate with trends previously observed. To assess the kinetics of Pgp-mediated transport, the results were analyzed by fitting the data to both currently proposed Pgp substrate translocation models-the vacuum cleaner and flippase models. While the resulting kinetic analysis in this study lends support predominantly to the vacuum cleaner model, this study most notably developed a novel method of assessing Pgp-mediated transport rates and real-time kinetics using surface plasmon resonance.
Collapse
Affiliation(s)
- Phuong H. Nguyen
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA, United States
| | - Shuolin Cui
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA, United States
| | - Amanda M. Kozarich
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA, United States
| | - Alex Rautio
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA, United States
| | - Arthur G. Roberts
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA, United States
| | - May P. Xiong
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA, United States
| |
Collapse
|
3
|
Weaver DR, Schaefer KG, King GM. Atomic force microscope kymograph analysis: A case study of two membrane proteins. Methods 2024; 223:83-94. [PMID: 38286332 DOI: 10.1016/j.ymeth.2024.01.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 01/09/2024] [Accepted: 01/10/2024] [Indexed: 01/31/2024] Open
Abstract
Kymograph analysis is employed across the biological atomic force microscopy (AFM) community to boost temporal resolution. The method is well suited for revealing protein dynamics at the single molecule level in near-native conditions. Yet, kymograph analysis comes with limitations that depend on several factors including protein geometry and instrumental drift. This work focuses on conformational dynamics of difficult-to-study sparse distributions of membrane proteins. We compare and contrast AFM kymograph analysis for two proteins, one of which (SecDF) exhibits conformational dynamics primarily in the vertical direction (normal to the membrane surface) and the other (Pgp) exhibits a combination of lateral dynamics and vertical motion. Common experimental issues are analyzed including translational and rotational drift. Conformational transition detection is evaluated via kymograph simulations followed by state detection algorithms. We find that kymograph analysis is largely robust to lateral drift. Displacement of the AFM line scan trajectory away from the protein center of mass by a few nanometers, roughly half of the molecule diameter, does not significantly affect transition detection nor generate undue dwell time errors. On the other hand, for proteins like Pgp that exhibit significant azimuthal maximum height dependence, rotational drift can potentially produce artifactual transitions. Measuring the height of a membrane protein protrusion is generally superior to measurement of width, confirming intuition based on vertical resolution superiority. In low signal-to-noise scenarios, common state detection algorithms struggle with transition detection as opposed to infinite hidden Markov models. AFM kymography represents a valuable addition to the membrane biophysics toolkit; continued hardware and software improvements are poised to expand the method's impact in the field.
Collapse
Affiliation(s)
- Dylan R Weaver
- Department of Physics and Astronomy, University of Missouri-Columbia, Columbia MO 65211 USA
| | - Katherine G Schaefer
- Department of Physics and Astronomy, University of Missouri-Columbia, Columbia MO 65211 USA
| | - Gavin M King
- Department of Physics and Astronomy, University of Missouri-Columbia, Columbia MO 65211 USA; Joint with Department of Biochemistry, University of Missouri-Columbia, Columbia MO 65211 USA.
| |
Collapse
|
4
|
Piska K, Koczurkiewicz-Adamczyk P, Jamrozik M, Bucki A, Kołaczkowski M, Pękala E. Comparative study on ABCB1-dependent efflux of anthracyclines and their metabolites: consequences for cancer resistance. Xenobiotica 2023; 53:507-514. [PMID: 37753851 DOI: 10.1080/00498254.2023.2264391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 09/25/2023] [Indexed: 09/28/2023]
Abstract
1. ABCB1 (P-glycoprotein, MDR1) is one of the most important transporter involved in cancer multi-drug resistance. It also plays a significant role in cancer resistance against anthracyclines, an anticancer group of drugs, including doxorubicin and daunorubicin. Several intracellular enzymes metabolise anthracyclines to carbonyl-reduced, hydroxy metabolites, which have impaired cytotoxic properties. However, metabolite efflux by ABCB1 transporter is not well characterised, while it may be the mechanism responsible for the metabolites' lack of activity.2. In this study recombinant ABCB1 ATPase transporter assay; anthracyclines accumulation assay in resistant cells overexpressing ABCB1; and molecular modelling were used to investigate anthracyclines: doxorubicin and daunorubicin and their carbonyl-reduced metabolites (doxorubicinol, daunorubicinol) susceptibility for ABCB1-dependent efflux.3. Based on the kinetics parameters of ATPase activity of ABCB1, it was found that daunorubicinol exerted an exceptionally high potential for being effluxed by the ABCB1 transporter. ABCB1 significantly affected the accumulation pattern of studied chemicals in resistant cancer cells. Doxorubicin and daunorubicinol accumulation were influenced by the activity of ABCB1 modulator - valspodar.4. Results indicate that ABCB1 activity affects not only anthracyclines but also their metabolites. Therefore crosstalk between the process of anthracyclines metabolism and metabolite efflux may be the mechanism of impairing anticancer properties of anthracyclines metabolites.
Collapse
Affiliation(s)
- Kamil Piska
- Department of Pharmaceutical Biochemistry, Faculty of Pharmacy, Jagiellonian University Medical College, Kraków, Poland
| | | | - Marek Jamrozik
- Department of Medicinal Chemistry, Faculty of Pharmacy, Jagiellonian University Medical College, Kraków, Poland
| | - Adam Bucki
- Department of Medicinal Chemistry, Faculty of Pharmacy, Jagiellonian University Medical College, Kraków, Poland
| | - Marcin Kołaczkowski
- Department of Medicinal Chemistry, Faculty of Pharmacy, Jagiellonian University Medical College, Kraków, Poland
| | - Elżbieta Pękala
- Department of Pharmaceutical Biochemistry, Faculty of Pharmacy, Jagiellonian University Medical College, Kraków, Poland
| |
Collapse
|
5
|
Mensah GAK, Schaefer KG, Bartlett MG, Roberts AG, King GM. Drug-Induced Conformational Dynamics of P-Glycoprotein Underlies the Transport of Camptothecin Analogs. Int J Mol Sci 2023; 24:16058. [PMID: 38003248 PMCID: PMC10671697 DOI: 10.3390/ijms242216058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 10/24/2023] [Accepted: 10/28/2023] [Indexed: 11/26/2023] Open
Abstract
P-glycoprotein (Pgp) plays a pivotal role in drug bioavailability and multi-drug resistance development. Understanding the protein's activity and designing effective drugs require insight into the mechanisms underlying Pgp-mediated transport of xenobiotics. In this study, we investigated the drug-induced conformational changes in Pgp and adopted a conformationally-gated model to elucidate the Pgp-mediated transport of camptothecin analogs (CPTs). While Pgp displays a wide range of conformations, we simplified it into three model states: 'open-inward', 'open-outward', and 'intermediate'. Utilizing acrylamide quenching of Pgp fluorescence as a tool to examine the protein's tertiary structure, we observed that topotecan (TPT), SN-38, and irinotecan (IRT) induced distinct conformational shifts in the protein. TPT caused a substantial shift akin to AMPPNP, suggesting ATP-independent 'open-outward' conformation. IRT and SN-38 had relatively moderate effects on the conformation of Pgp. Experimental atomic force microscopy (AFM) imaging supports these findings. Further, the rate of ATPase hydrolysis was correlated with ligand-induced Pgp conformational changes. We hypothesize that the separation between the nucleotide-binding domains (NBDs) creates a conformational barrier for substrate transport. Substrates that reduce the conformational barrier, like TPT, are better transported. The affinity for ATP extracted from Pgp-mediated ATP hydrolysis kinetics curves for TPT was about 2-fold and 3-fold higher than SN-38 and IRT, respectively. On the contrary, the dissociation constants (KD) determined by fluorescence quenching for these drugs were not significantly different. Saturation transfer double difference (STDD) NMR of TPT and IRT with Pgp revealed that similar functional groups of the CPTs are accountable for Pgp-CPTs interactions. Efforts aimed at modifying these functional groups, guided by available structure-activity relationship data for CPTs and DNA-Topoisomerase-I complexes, could pave the way for the development of more potent next-generation CPTs.
Collapse
Affiliation(s)
- Gershon A. K. Mensah
- Department of Pharmaceutical and Biomedical Science, University of Georgia, Athens, GA 30602, USA; (G.A.K.M.)
| | - Katherine G. Schaefer
- Department of Physics and Astronomy, University of Missouri, Columbia, MO 65211, USA;
| | - Michael G. Bartlett
- Department of Pharmaceutical and Biomedical Science, University of Georgia, Athens, GA 30602, USA; (G.A.K.M.)
| | - Arthur G. Roberts
- Department of Pharmaceutical and Biomedical Science, University of Georgia, Athens, GA 30602, USA; (G.A.K.M.)
| | - Gavin M. King
- Department of Physics and Astronomy, University of Missouri, Columbia, MO 65211, USA;
- Joint with Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA
| |
Collapse
|
6
|
Walsh OD, Choi L, Sigdel KP. Effect of CM15 on Supported Lipid Bilayer Probed by Atomic Force Microscopy. MEMBRANES 2023; 13:864. [PMID: 37999350 PMCID: PMC10672887 DOI: 10.3390/membranes13110864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 10/26/2023] [Accepted: 10/26/2023] [Indexed: 11/25/2023]
Abstract
Antimicrobial peptides are key components of the immune system. These peptides affect the membrane in various ways; some form nano-sized pores, while others only produce minor defects. Since these peptides are increasingly important in developing antimicrobial drugs, understanding the mechanism of their interactions with lipid bilayers is critical. Here, using atomic force microscopy (AFM), we investigated the effect of a synthetic hybrid peptide, CM15, on the membrane surface comprising E. coli polar lipid extract. Direct imaging of supported lipid bilayers exposed to various concentrations of the peptide revealed significant membrane remodeling. We found that CM15 interacts with supported lipid bilayers and forms membrane-spanning defects very quickly. It is found that CM15 is capable of remodeling both leaflets of the bilayer. For lower CM15 concentrations, punctate void-like defects were observed, some of which re-sealed themselves as a function of time. However, for CM15 concentrations higher than 5 µM, the defects on the bilayers became so widespread that they disrupted the membrane integrity completely. This work enhances the understanding of CM15 interactions with the bacterial lipid bilayer.
Collapse
Affiliation(s)
| | | | - Krishna P. Sigdel
- Department of Physics and Astronomy, California State Polytechnic University, Pomona, CA 91768, USA
| |
Collapse
|
7
|
Schaefer KG, Roberts AG, King GM. Advantages and potential limitations of applying AFM kymograph analysis to pharmaceutically relevant membrane proteins in lipid bilayers. Sci Rep 2023; 13:11427. [PMID: 37454132 PMCID: PMC10349840 DOI: 10.1038/s41598-023-37910-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 06/29/2023] [Indexed: 07/18/2023] Open
Abstract
Membrane proteins play critical roles in disease and in the disposition of many pharmaceuticals. A prime example is P-glycoprotein (Pgp) which moves a diverse range of drugs across membranes and out of the cell before a therapeutic payload can be delivered. Conventional structural biology methods have provided a valuable framework for comprehending the complex conformational changes underlying Pgp function, which also includes ATPase activity, but the lack of real-time information hinders understanding. Atomic force microscopy (AFM) is a single-molecule technique that is well-suited for studying active membrane proteins in bilayers and is poised to advance the field beyond static snapshots. After verifying Pgp activity in surface-support bilayers, we used kymograph analysis in conjunction with AFM imaging and simulations to study structural transitions at the 100 ms timescale. Though kymographs are frequently employed to boost temporal resolution, the limitations of the method have not been well characterized, especially for sparse non-crystalline distributions of pharmaceutically relevant membrane proteins like Pgp. Common experimental challenges are analyzed, including protein orientation, instrument noise, and drift. Surprisingly, a lateral drift of 75% of the protein dimension leads to only a 12% probability of erroneous state transition detection; average dwell time error achieves a maximum value of 6%. Rotational drift of proteins like Pgp, with azimuthally-dependent maximum heights, can lead to artifactual transitions. Torsional constraints can alleviate this potential pitfall. Confidence in detected transitions can be increased by adding conformation-altering ligands such as non-hydrolysable analogs. Overall, the data indicate that AFM kymographs are a viable method to access conformational dynamics for Pgp, but generalizations of the method should be made with caution.
Collapse
Affiliation(s)
- Katherine G Schaefer
- Department of Physics and Astronomy, University of Missouri, Columbia, MO, 65211, USA
| | - Arthur G Roberts
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA, 30602, USA.
| | - Gavin M King
- Department of Physics and Astronomy, University of Missouri, Columbia, MO, 65211, USA.
- Joint With Department of Biochemistry, University of Missouri, Columbia, MO, 65211, USA.
| |
Collapse
|
8
|
Sun H, Wang J. Novel perspective for protein-drug interaction analysis: atomic force microscope. Analyst 2023; 148:454-474. [PMID: 36398684 DOI: 10.1039/d2an01591a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Proteins are major drug targets, and drug-target interaction identification and analysis are important factors for drug discovery. Atomic force microscopy (AFM) is a powerful tool making it possible to image proteins with nanometric resolution and probe intermolecular forces under physiological conditions. We review recent studies conducted in the field of target protein drug discovery using AFM-based analysis technology, including drug-driven changes in nanomechanical properties of protein morphology and interactions. Underlying mechanisms (including thermodynamic and kinetic parameters) of the drug-target interaction and drug-modulating protein-protein interaction (PPI) on the surfaces of models or living cells are discussed. Furthermore, challenges and the outlook for the field are likewise discussed. Overall, this insight into the mechanical properties of protein-drug interactions provides an unprecedented information framework for rational drug discovery in the pharmaceutical field.
Collapse
Affiliation(s)
- Heng Sun
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, 400044, China.
| | - Jianhua Wang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, 400044, China.
| |
Collapse
|
9
|
Nanoparticles-Based Strategies to Improve the Delivery of Therapeutic Small Interfering RNA in Precision Oncology. Pharmaceutics 2022; 14:pharmaceutics14081586. [PMID: 36015212 PMCID: PMC9415718 DOI: 10.3390/pharmaceutics14081586] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 07/14/2022] [Accepted: 07/23/2022] [Indexed: 02/07/2023] Open
Abstract
Small interfering RNA (siRNA) can selectively suppress the expression of disease-causing genes, holding great promise in the treatment of human diseases, including malignant cancers. In recent years, with the development of chemical modification and delivery technology, several siRNA-based therapeutic drugs have been approved for the treatment of non-cancerous liver diseases. Nevertheless, the clinical development of siRNA-based cancer therapeutics remains a major translational challenge. The main obstacles of siRNA therapeutics in oncology include both extracellular and intracellular barriers, such as instability under physiological conditions, insufficient tumor targeting and permeability (particularly for extrahepatic tumors), off-target effects, poor cellular uptake, and inefficient endosomal escape. The development of clinically suitable and effective siRNA delivery systems is expected to overcome these challenges. Herein, we mainly discuss recent strategies to improve the delivery and efficacy of therapeutic siRNA in cancer, including the application of non-viral nanoparticle-based carriers, the selection of target genes for therapeutic silencing, and the combination with other therapeutic modalities. In addition, we also provide an outlook on the ongoing challenges and possible future developments of siRNA-based cancer therapeutics during clinical translation.
Collapse
|
10
|
Clouser AF, Atkins WM. Long Range Communication between the Drug-Binding Sites and Nucleotide Binding Domains of the Efflux Transporter ABCB1. Biochemistry 2022; 61:730-740. [PMID: 35384651 PMCID: PMC9022228 DOI: 10.1021/acs.biochem.2c00056] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The ABC efflux pump
P-glycoprotein (P-gp) transports a wide variety
of drugs and is inhibited by others. Some drugs stimulate ATP hydrolysis
at the nucleotide binding domains (NBDs) and are transported, others
uncouple ATP hydrolysis and transport, and others inhibit ATP hydrolysis.
The molecular basis for the different behavior of these drugs is not
well understood despite the availability of several structural models
of P-gp complexes with ligands bound. Hypothetically, ligands differentially
alter the conformational dynamics of peptide segments that mediate
the coupling between the drug binding sites and the NBDs. Here, we
explore by hydrogen-deuterium exchange mass spectrometry the dynamic
consequences of a classic substrate and inhibitor, vinblastine and
zosuquidar, binding to mouse P-gp (mdr1a) in lipid nanodiscs. The
dynamics of P-gp in nucleotide-free, pre-hydrolysis, and post-hydrolysis
states in the presence of each drug reveal distinct mechanisms of
ATPase stimulation and implications for transport. For both drugs,
there are common regions affected in a similar manner, suggesting
that particular networks are the key to stimulating ATP hydrolysis.
However, drug binding effects diverge in the post-hydrolysis state,
particularly in the intracellular helices (ICHs 3 and 4) and neighboring
transmembrane helices. The local dynamics and conformational equilibria
in this region are critical for the coupling of drug binding and ATP
hydrolysis and are differentially modulated in the catalytic cycle.
Collapse
Affiliation(s)
- Amanda F Clouser
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington 98195-7610, United States
| | - William M Atkins
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington 98195-7610, United States
| |
Collapse
|
11
|
Schaefer KG, Pittman AE, Barrera FN, King GM. Atomic force microscopy for quantitative understanding of peptide-induced lipid bilayer remodeling. Methods 2022; 197:20-29. [PMID: 33164792 DOI: 10.1016/j.ymeth.2020.10.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 10/17/2020] [Accepted: 10/20/2020] [Indexed: 12/15/2022] Open
Abstract
A number of peptides are known to bind lipid bilayer membranes and cause these natural barriers to leak in an uncontrolled manner. Though membrane permeabilizing peptides play critical roles in cellular activity and may have promising future applications in the therapeutic arena, significant questions remain about their mechanisms of action. The atomic force microscope (AFM) is a single molecule imaging tool capable of addressing lipid bilayers in near-native fluid conditions. The apparatus complements traditional assays by providing local topographic maps of bilayer remodeling induced by membrane permeabilizing peptides. The information garnered from the AFM includes direct visualization and statistical analyses of distinct bilayer remodeling modes such as highly localized pore-like voids in the bilayer and dispersed thinned membrane regions. Colocalization of distinct remodeling modes can be studied. Here we examine recent work in the field and outline methods used to achieve precise AFM image data. Experimental challenges and common pitfalls are discussed as well as techniques for unbiased analysis including the Hessian blob detection algorithm, bootstrapping, and the Bayesian information criterion. When coupled with robust statistical analyses, high precision AFM data is poised to advance understanding of an important family of peptides that cause poration of membrane bilayers.
Collapse
Affiliation(s)
- K G Schaefer
- Department of Physics and Astronomy, University of Missouri-Columbia, Columbia, MO 65211, USA
| | - A E Pittman
- Department of Physics and Astronomy, University of Missouri-Columbia, Columbia, MO 65211, USA
| | - F N Barrera
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
| | - G M King
- Department of Physics and Astronomy, University of Missouri-Columbia, Columbia, MO 65211, USA; Department of Biochemistry, University of Missouri-Columbia, Columbia, MO 65211, USA.
| |
Collapse
|
12
|
Cao Y, Shi Y, Cai Y, Hong Z, Chai Y. The Effects of Traditional Chinese Medicine on P-Glycoprotein–Mediated Multidrug Resistance and Approaches for Studying the Herb–P-Glycoprotein Interactions. Drug Metab Dispos 2020; 48:972-979. [DOI: 10.1124/dmd.120.000050] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 07/20/2020] [Indexed: 12/14/2022] Open
|
13
|
İstİflİ ES, ŞihoĞlu Tepe A, SarikÜrkcÜ C, Tepe B. Interaction of certain monoterpenoid hydrocarbons with the receptor binding domain of 2019 novel coronavirus (2019-nCoV), transmembrane serine protease 2 (TMPRSS2), cathepsin B, and cathepsin L (CatB/L) and their pharmacokinetic properties. Turk J Biol 2020; 44:242-264. [PMID: 32595360 PMCID: PMC7314502 DOI: 10.3906/biy-2005-46] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
As of June 2020, the coronavirus disease 19 (COVID-19) caused by the 2019 new type coronavirus (2019-nCoV) infected more than 7,000,000 people worldwide and caused the death of more than 400,000 people. The aim of this study was to investigate the molecular interactions between monoterpenoids and spike protein of 2019-nCoV together with the cellular proteases [transmembrane serine protease 2 (TMPRSS2), cathepsin B (CatB), and cathepsin L (CatL)]. As a result of the relative binding capacity index (RBCI) analysis, carvone was found to be the most effective molecule against all targets when binding energy and predicted (theoretical) IC50 data were evaluated together. It was found to exhibit drug-likeness property according to the Lipinski's rule-of-five. Carvone has also been determined to be able to cross the blood-brain barrier (BBB) effectively, not a substrate for P-glycoprotein (P-gp), not to inhibit any of the cytochrome P molecules, and to have no toxic effects even on liver cells. In addition, the LD50 dose of carvone in rats was 1.707 mol/kg. Due to its interaction profile with target proteins and excellent pharmacokinetic properties, it has been concluded that carvone can be considered as an alternative agent in drug development studies against 2019-nCoV.
Collapse
Affiliation(s)
- Erman Salih İstİflİ
- Department of Biology, Faculty of Science and Literature, Çukurova University, Adana Turkey
| | - Arzuhan ŞihoĞlu Tepe
- Department of Biology, Faculty of Science and Literature, Gaziantep University, Gaziantep Turkey
| | - Cengiz SarikÜrkcÜ
- Department of Analytical Chemistry, Faculty of Pharmacy, Afyonkarahisar Health Sciences University, Afyonkarahisar Turkey
| | - Bektaş Tepe
- Department of Molecular Biology and Genetics, Faculty of Science and Literature, Kilis 7 Aralık University, Kilis Turkey
| |
Collapse
|