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Mulay AR, Hwang J, Kim DH. Microphysiological Blood-Brain Barrier Systems for Disease Modeling and Drug Development. Adv Healthc Mater 2024; 13:e2303180. [PMID: 38430211 PMCID: PMC11338747 DOI: 10.1002/adhm.202303180] [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: 09/20/2023] [Revised: 02/22/2024] [Indexed: 03/03/2024]
Abstract
The blood-brain barrier (BBB) is a highly controlled microenvironment that regulates the interactions between cerebral blood and brain tissue. Due to its selectivity, many therapeutics targeting various neurological disorders are not able to penetrate into brain tissue. Pre-clinical studies using animals and other in vitro platforms have not shown the ability to fully replicate the human BBB leading to the failure of a majority of therapeutics in clinical trials. However, recent innovations in vitro and ex vivo modeling called organs-on-chips have shown the potential to create more accurate disease models for improved drug development. These microfluidic platforms induce physiological stressors on cultured cells and are able to generate more physiologically accurate BBBs compared to previous in vitro models. In this review, different approaches to create BBBs-on-chips are explored alongside their application in modeling various neurological disorders and potential therapeutic efficacy. Additionally, organs-on-chips use in BBB drug delivery studies is discussed, and advances in linking brain organs-on-chips onto multiorgan platforms to mimic organ crosstalk are reviewed.
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Affiliation(s)
- Atharva R. Mulay
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Baltimore, Maryland 21218
| | - Jihyun Hwang
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Baltimore, Maryland 21218
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, 21205
| | - Deok-Ho Kim
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, 21205
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21205
- Center for Microphysiological Systems, Johns Hopkins University School of Medicine, Baltimore, MD, 21205
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, 21218
- Institute for NanoBioTechnology, Johns Hopkins University, Baltimore, 21218
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2
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Yang T, Curtis S, Bai A, Young A, Derosier D, Ripley S, Bai S. CRISPR/Cas9 targeting liposomes knocked down multidrug resistance proteins in brain endothelial cells as a model to predict potential pharmacoresistance. Colloids Surf B Biointerfaces 2023; 222:113103. [PMID: 36571980 PMCID: PMC9899320 DOI: 10.1016/j.colsurfb.2022.113103] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 11/01/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022]
Abstract
This investigation aimed to use CRISPR-Cas9 gene-editing to knock down P-glycoprotein (P-gp) expression and then establish a feasible cell line to evaluate the potential pharmacoresistance of therapeutic agents mediated by efflux. A cationic liposome was prepared as a "smart bomb" by conjugating with a peptide-based targeting ligand (THRPPMWSPVWP), specifically binding to transferrin receptors at the blood-brain barrier (BBB), and then formed a nanocomplex with P-gp knockdown CRISPR/Cas9 plasmid. Higher uptakes of targeted and stable liposomes in bEND.3 cells were observed compared to non-peptide conjugated ones (p < 0.05). The P-gp transporters were successfully knocked down by the cell-nontoxic CRISPR/Cas9 targeted liposomes and P-gp associated ATP activities were higher in the transfected cells (p < 0.05). Functional studies of knocked down cells were evaluated by using prototypical P-gp substrates rhodamine 123 and doxorubicin. More accumulation of rhodamine 123 and higher cytotoxic sensitivity of doxorubicin was observed in the transfected cells as compared with those in the wild-type cells.
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Affiliation(s)
- Tianzhi Yang
- Department of Pharmaceutical Sciences, School of Pharmacy, Husson University, Bangor, ME 04401, USA
| | - Skye Curtis
- Department of Pharmaceutical Sciences, School of Pharmacy, Husson University, Bangor, ME 04401, USA
| | - Albert Bai
- Department of Pharmaceutical Sciences, School of Pharmacy, Husson University, Bangor, ME 04401, USA
| | - Abby Young
- Department of Pharmaceutical Sciences, School of Pharmacy, Husson University, Bangor, ME 04401, USA
| | - Derek Derosier
- Department of Pharmaceutical Sciences, School of Pharmacy, Husson University, Bangor, ME 04401, USA
| | - Shannon Ripley
- Department of Pharmaceutical Sciences, School of Pharmacy, Husson University, Bangor, ME 04401, USA
| | - Shuhua Bai
- Department of Pharmaceutical Sciences, School of Pharmacy, Husson University, Bangor, ME 04401, USA.
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Chen YP, Chou CM, Chang TY, Ting H, Dembélé J, Chu YT, Liu TP, Changou CA, Liu CW, Chen CT. Bridging Size and Charge Effects of Mesoporous Silica Nanoparticles for Crossing the Blood–Brain Barrier. Front Chem 2022; 10:931584. [PMID: 35880111 PMCID: PMC9307501 DOI: 10.3389/fchem.2022.931584] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 05/12/2022] [Indexed: 12/05/2022] Open
Abstract
The blood–brain barrier (BBB) is a highly selective cellular barrier that tightly controls the microenvironment of the central nervous system to restrict the passage of substances, which is a primary challenge in delivering therapeutic drugs to treat brain diseases. This study aimed to develop simple surface modifications of mesoporous silica nanoparticles (MSNs) without external stimuli or receptor protein conjugation, which exhibited a critical surface charge and size allowing them to cross the BBB. A series of MSNs with various charges and two different sizes of 50 and 200 nm were synthesized, which showed a uniform mesoporous structure with various surface zeta potentials ranging from +42.3 to −51.6 mV. Confocal microscopic results showed that 50 nm of strongly negatively charged N4-RMSN50@PEG/THPMP (∼−40 mV) could be significantly observed outside blood vessels of the brain in Tg(zfli1:EGFP) transgenic zebrafish embryos superior to the other negatively charged MSNs. However, very few positively charged MSNs were found in the brain, indicating that negatively charged MSNs could successfully penetrate the BBB. The data were confirmed by high-resolution images of 3D deconvoluted confocal microscopy and two-photon microscopy and zebrafish brain tissue sections. In addition, while increasing the size to 200 nm but maintaining the similar negative charge (∼40 mV), MSNs could not be detected in the brain of zebrafish, suggesting that transport across the BBB based on MSNs occurred in charge- and size-dependent manners. No obvious cytotoxicity was observed in the CTX-TNA2 astrocyte cell line and U87-MG glioma cell line treated with MSNs. After doxorubicin (Dox) loading, N4-RMSN50@PEG/THPMP/Dox enabled drug delivery and pH-responsive release. The toxicity assay showed that N4-RMSN50@PEG/THPMP could reduce Dox release, resulting in the increase of the survival rate in zebrafish. Flow cytometry demonstrated N4-RMSN50@PEG/THPMP had few cellular uptakes. Protein corona analysis revealed three transporter proteins, such as afamin, apolipoprotein E, and basigin, could contribute to BBB penetration, validating the possible mechanism of N4-RMSN50@PEG/THPMP crossing the BBB. With this simple approach, MSNs with critical negative charge and size could overcome the BBB-limiting characteristics of therapeutic drug molecules; furthermore, their use may also cause drug sustained-release in the brain, decreasing peripheral toxicity.
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Affiliation(s)
- Yi-Ping Chen
- Graduate Institute of Nanomedicine and Medical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei, Taiwan
- International PhD Program in Biomedical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei, Taiwan
| | - Chih-Ming Chou
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Department of Biochemistry and Molecular Cell Biology, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Tsu-Yuan Chang
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Department of Biochemistry and Molecular Cell Biology, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Hao Ting
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Department of Biochemistry and Molecular Cell Biology, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Julien Dembélé
- Graduate Institute of Biomedical Materials and Tissue Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei, Taiwan
| | - You-Tai Chu
- Graduate Institute of Nanomedicine and Medical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei, Taiwan
| | - Tsang-Pai Liu
- Department of Surgery, Mackay Memorial Hospital, Taipei, Taiwan
| | - Chun A. Changou
- The PhD Program for Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Chien-Wei Liu
- Department of Information Management, St. Mary’s Junior College of Medicine, Nursing and Management, Yilan, Taiwan
| | - Chien-Tsu Chen
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Department of Biochemistry and Molecular Cell Biology, College of Medicine, Taipei Medical University, Taipei, Taiwan
- *Correspondence: Chien-Tsu Chen,
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Shabani L, Abbasi M, Amini M, Amani AM, Vaez A. The brilliance of nanoscience over cancer therapy: Novel promising nanotechnology-based methods for eradicating glioblastoma. J Neurol Sci 2022; 440:120316. [DOI: 10.1016/j.jns.2022.120316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 05/28/2022] [Accepted: 05/31/2022] [Indexed: 10/18/2022]
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Abstract
The blood-brain barrier (BBB) is an interface between cerebral blood and the brain parenchyma. As a gate keeper, BBB regulates passage of nutrients and exogeneous compounds. Owing to this highly selective barrier, many drugs targeting brain diseases are not likely to pass through the BBB. Thus, a large amount of time and cost have been paid for the development of BBB targeted therapeutics. However, many drugs validated in in vitro models and animal models have failed in clinical trials primarily due to the lack of an appropriate BBB model. Human BBB has a unique cellular architecture. Different physiologies between human and animal BBB hinder the prediction of drug responses. Therefore, a more physiologically relevant alternative BBB model needs to be developed. In this review, we summarize major features of human BBB and current BBB models and describe organ-on-chip models for BBB modeling and their applications in neurological complications.
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Affiliation(s)
- Baofang Cui
- Department of Biotechnology, Yonsei University, Seoul 03722, Korea
| | - Seung-Woo Cho
- Department of Biotechnology, Yonsei University, Seoul 03722, Korea
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Nirusimhan V, Andrew Gideon D, Parashar A, Jeyachandran S, Jeyaraman J, Subbaraj G, Kulanthaivel L. Structural Modeling of Drosophila melanogaster Gut Cytochrome P450s and Docking Comparison of Fruit Fly Gut and Human Cytochrome P450s. Curr Drug Metab 2022; 23:299-316. [PMID: 35546755 DOI: 10.2174/1389200223666220511162234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 02/01/2022] [Accepted: 02/15/2022] [Indexed: 11/22/2022]
Abstract
Drosophila melanogaster is a prominent model organism in developmental biology research and in studies related to pathophysiological conditions like cancer and Alzheimer's disease. The fruit fly gut contains several cytochrome P450s (CYP450s) which have central roles in Drosophila development and in the normal physiology of the gut. Since the crystal structures of these proteins have not been deciphered yet, we modeled the structure of 29 different D. melanogaster gut CYP450s using Prime (Schrödinger). The sequences of chosen D. melanogaster gut CYP450s were compared with that of their human counterparts. The common gut (and liver) microsomal CYP450s in humans were chosen for structural comparison to find the homology and identity % of D. melanogaster CYPs with that of their human counterparts. The modeled structures were validated using PROCHECK and the best fit models were used for docking several known human pharmacological agents/drugs to the modeled D. melanogaster gut CYP450s. Based on the binding affinities (ΔG values) of the selected drug molecules with the modeled fly gut CYPs, the plausible differences in metabolism of the prominent drugs in humans and fly were projected. The gut is involved in absorption of oral drugs/pharmacological agents and hence, upregulation of intestinal CYP450 and their reactions with endobiotics and xenobiotics is envisaged. The insights gleaned from this work can validate D. melanogaster as a model organism for studying intestinal drug metabolism, particularly in the context of a) toxicology of pharmacological agents to the gut cells and b) how gut P450 metabolites/products can influence gut homeostasis. This work can help establish a platform for further in vitro investigations on how intestinal CYP450 metabolism can influence gut health. The data from this work can be used for further in silico studies and this work can serve as a platform for future in vitro investigations on intestinal CYP450-mediated metabolism of endo- and xeno-biotics in D. melanogaster.
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Affiliation(s)
- Vijay Nirusimhan
- Cancer Informatics Laboratory, Department of Bioinformatics, Alagappa University, Science Campus, Karaikudi, Tamil Nadu, India
| | - Daniel Andrew Gideon
- Department of Biotechnology and Bioinformatics, Bishop Heber College (Autonomous), Tennur, Tiruchirappalli Tamil Nadu, India
| | - Abhinav Parashar
- Department of Biotechnology, Vignan's Foundation for Science, Technology & Research, Vadlamudi, Guntur, Andhra Pradesh, India
| | - Sangavi Jeyachandran
- Cancer Informatics Laboratory, Department of Bioinformatics, Alagappa University, Science Campus, Karaikudi, Tamil Nadu, India
| | - Jeyakanthan Jeyaraman
- Structural Biology and Bio-Computing Lab, Department of Bioinformatics, Science Campus, Alagappa University, Karaikudi, Tamil Nadu, India
| | - Gowthamkumar Subbaraj
- Faculty of Allied Health Sciences, Chettinad Hospital & Research Institute, Chettinad Academy of Research and Education, Kelambakkam, Tamil Nadu, India
| | - Langeswaran Kulanthaivel
- Cancer Informatics Laboratory, Department of Bioinformatics, Alagappa University, Science Campus, Karaikudi, Tamil Nadu, India
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7
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Cui B, Cho SW. Blood-brain barrier-on-a-chip for brain disease modeling and drug testing. BMB Rep 2022; 55:213-219. [PMID: 35410642 PMCID: PMC9152581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/22/2022] [Accepted: 03/22/2022] [Indexed: 09/17/2023] Open
Abstract
The blood-brain barrier (BBB) is an interface between cerebral blood and the brain parenchyma. As a gate keeper, BBB regulates passage of nutrients and exogeneous compounds. Owing to this highly selective barrier, many drugs targeting brain diseases are not likely to pass through the BBB. Thus, a large amount of time and cost have been paid for the development of BBB targeted therapeutics. However, many drugs validated in in vitro models and animal models have failed in clinical trials primarily due to the lack of an appropriate BBB model. Human BBB has a unique cellular architecture. Different physiologies between human and animal BBB hinder the prediction of drug responses. Therefore, a more physiologically relevant alternative BBB model needs to be developed. In this review, we summarize major features of human BBB and current BBB models and describe organ-on-chip models for BBB modeling and their applications in neurological complications. [BMB Reports 2022; 55(5): 213-219].
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Affiliation(s)
- Baofang Cui
- Department of Biotechnology, Yonsei University, Seoul 03722, Korea
| | - Seung-Woo Cho
- Department of Biotechnology, Yonsei University, Seoul 03722, Korea
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8
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Development of an a priori computational approach for brain uptake of compounds in an insect model system. Bioorg Med Chem Lett 2021; 40:127930. [PMID: 33711441 DOI: 10.1016/j.bmcl.2021.127930] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 02/17/2021] [Accepted: 02/28/2021] [Indexed: 11/20/2022]
Abstract
Delivery of compounds to the brain is critical for the development of effective treatment therapies of multiple central nervous system diseases. Recently a novel insect-based brain uptake model was published utilizing a locust brain ex vivo system. The goal of our study was to develop a priori, in silico cheminformatic models to describe brain uptake in this insect model, as well as evaluate the predictive ability. The machine learning program Orange® was used to evaluate several machine learning (ML) models on a published data set of 25 known drugs, with in vitro data generated by a single laboratory group to reduce inherent inter-laboratory variability. The ML models included in this study were linear regression (LR), support vector machines (SVN), k-nearest neighbor (kNN) and neural nets (NN). The quantitative structure-property relationship models were able to correlate experimental logCtot (concentration of compound in brain) and predicted brain uptake of r2 > 0.5, with the descriptors log(P*MW-0.5) and hydrogen bond donor used in LR, SVN and KNN, while log(P*MW-0.5) and total polar surface area (TPSA) descriptors used in the NN models. Our results indicate that the locust insect model is amenable to data mining chemoinformatics and in silico model development in CNS drug discovery pipelines.
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Thapa P, Upadhyay SP, Suo WZ, Singh V, Gurung P, Lee ES, Sharma R, Sharma M. Chalcone and its analogs: Therapeutic and diagnostic applications in Alzheimer's disease. Bioorg Chem 2021; 108:104681. [PMID: 33571811 PMCID: PMC7928223 DOI: 10.1016/j.bioorg.2021.104681] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 12/15/2020] [Accepted: 01/20/2021] [Indexed: 02/08/2023]
Abstract
Chalcone [(E)-1,3-diphenyl-2-propene-1-one], a small molecule with α, β unsaturated carbonyl group is a precursor or component of many natural flavonoids and isoflavonoids. It is one of the privileged structures in medicinal chemistry. It possesses a wide range of biological activities encouraging many medicinal chemists to study this scaffold for its usefulness to oncology, infectious diseases, virology and neurodegenerative diseases including Alzheimer's disease (AD). Small molecular size, convenient and cost-effective synthesis, and flexibility for modifications to modulate lipophilicity suitable for blood brain barrier (BBB) permeability make chalcones a preferred candidate for their therapeutic and diagnostic potential in AD. This review summarizes and highlights the importance of chalcone and its analogs as single target small therapeutic agents, multi-target directed ligands (MTDLs) as well as molecular imaging agents for AD. The information summarized here will guide many medicinal chemist and researchers involved in drug discovery to consider chalcone as a potential scaffold for the development of anti-AD agents including theranostics.
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Affiliation(s)
- Pritam Thapa
- Drug Discovery Program, Midwest Veterans' Biomedical Research Foundation, KCVA Medical Center, Kansas City, MO 64128, USA.
| | - Sunil P Upadhyay
- Drug Discovery Program, Midwest Veterans' Biomedical Research Foundation, KCVA Medical Center, Kansas City, MO 64128, USA
| | - William Z Suo
- Laboratory for Alzheimer's Disease & Aging Research, Veterans Affairs Medical Center, Kansas City, MO 64128, USA
| | - Vikas Singh
- Division of Neurology, KCVA Medical Center, Kansas City, MO, USA
| | - Prajwal Gurung
- Inflammation Program, University of Iowa, Iowa City, IA 52242, USA
| | - Eung Seok Lee
- College of Pharmacy, Yeungnam University, Gyeongsan 712-749, Republic of Korea
| | - Ram Sharma
- Drug Discovery Program, Midwest Veterans' Biomedical Research Foundation, KCVA Medical Center, Kansas City, MO 64128, USA
| | - Mukut Sharma
- Drug Discovery Program, Midwest Veterans' Biomedical Research Foundation, KCVA Medical Center, Kansas City, MO 64128, USA
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Radchenko EV, Dyabina AS, Palyulin VA. Towards Deep Neural Network Models for the Prediction of the Blood-Brain Barrier Permeability for Diverse Organic Compounds. Molecules 2020; 25:molecules25245901. [PMID: 33322142 PMCID: PMC7763607 DOI: 10.3390/molecules25245901] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 12/06/2020] [Accepted: 12/10/2020] [Indexed: 11/24/2022] Open
Abstract
Permeation through the blood–brain barrier (BBB) is among the most important processes controlling the pharmacokinetic properties of drugs and other bioactive compounds. Using the fragmental (substructural) descriptors representing the occurrence number of various substructures, as well as the artificial neural network approach and the double cross-validation procedure, we have developed a predictive in silico LogBB model based on an extensive and verified dataset (529 compounds), which is applicable to diverse drugs and drug-like compounds. The model has good predictivity parameters (Q2=0.815, RMSEcv=0.318) that are similar to or better than those of the most reliable models available in the literature. Larger datasets, and perhaps more sophisticated network architectures, are required to realize the full potential of deep neural networks. The analysis of fragment contributions reveals patterns of influence consistent with the known concepts of structural characteristics that affect the BBB permeability of organic compounds. The external validation of the model confirms good agreement between the predicted and experimental LogBB values for most of the compounds. The model enables the evaluation and optimization of the BBB permeability of potential neuroactive agents and other drug compounds.
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More SK, Pawar AP. Preparation, optimization and preliminary pharmacokinetic study of curcumin encapsulated turmeric oil microemulsion in zebra fish. Eur J Pharm Sci 2020; 155:105539. [PMID: 32898637 DOI: 10.1016/j.ejps.2020.105539] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 08/05/2020] [Accepted: 09/03/2020] [Indexed: 01/17/2023]
Abstract
The present investigation aimed to develop curcumin loaded turmeric oil microemulsion for brain targeting. An effort has been made to investigate the role of functional components in developing brain targeted formulation which could enhance the bioavailability and uptake of drug in the brain upon oral administration. Preliminary studies like solubility study, emulsification study and construction of the pseudo ternary phase diagram were performed for screening components. The formulation was optimized by using extreme vertices mixture design. The optimized formulation was characterized for appearance, stability to centrifugation, dilution potential, globule size, zeta potential and drug content. Furthermore, ex-vivo permeation in chicken gut sac non everted technique and pharmacokinetic study in adult zebra fishes were carried out. The optimized formulation was found to clear, yellow-colored with the absence of phase separation and precipitation denoted the stability of formulation to centrifugation and dilution. The mean globule size, polydispersity index, zeta potential and drug content was observed as 29.13± 0.12 nm, 0.23 ± 0.01,-12.33 ± 1.37 mV and 99.10±3.91 %, respectively. Ex vivo permeation study revealed 2.41 fold enhancement in the steady-state flux when compared to curcumin solution. Furthermore, optimized formulation showed shorter Tmax (5 min) and higher AUC(0-∞) (7.93 μg/brain*min) compared to the curcumin solution which showed similar Tmax and AUC(0-∞) of 2.78 μg/brain*min after oral administration to zebra fishes revealing 3.97 fold enhancement. The results revealed enhanced ex vivo oral absorption and enhanced in vivo brain pharmacokinetics of curcumin via functional microemulsion in the zebra fish model.
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Affiliation(s)
- Suraj Kewal More
- Department of Pharmaceutics, Poona College of Pharmacy, Bharati Vidyapeeth (Deemed to be University), Paud Road, Erandwane, Pune 411038, India.
| | - Atmaram Pandurang Pawar
- Department of Pharmaceutics, Poona College of Pharmacy, Bharati Vidyapeeth (Deemed to be University), Paud Road, Erandwane, Pune 411038, India.
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Yang T, Ferrill L, Gallant L, McGillicuddy S, Fernandes T, Schields N, Bai S. Verapamil and riluzole cocktail liposomes overcome pharmacoresistance by inhibiting P-glycoprotein in brain endothelial and astrocyte cells: A potent approach to treat amyotrophic lateral sclerosis. Eur J Pharm Sci 2018; 120:30-39. [PMID: 29704642 DOI: 10.1016/j.ejps.2018.04.026] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Revised: 04/03/2018] [Accepted: 04/18/2018] [Indexed: 12/13/2022]
Abstract
Riluzole is currently one of two approved medications for the treatment of amyotrophic lateral sclerosis (ALS). However, brain disposition of riluzole, as a substrate of P-glycoprotein (P-gp), is limited by the efflux transporters at the blood-brain barrier (BBB). We propose to develop a liposomal co-delivery system that could effectively transport riluzole to brain cells by reducing efflux pumps with a P-gp inhibitor, verapamil. Riluzole and verapamil cocktail liposomes were prepared by lipid film hydration. The average particle size of cocktail liposomes was 194.3 ± 6.0 nm and their polydispersity index (PDI) was 0.272 ± 0.017. The encapsulation efficiencies of verapamil and riluzole in the cocktail liposomes were 86.0 ± 1.4% and 85.6 ± 1.1%, respectively. The drug release from cocktail liposomes after 8 h in PBS at 37 °C was 78.4 ± 6.2% of riluzole and 76.7 ± 3.8% of verapamil. The average particle size of liposomes did not show significant changes at 4 °C after three months. Verapamil cocktail liposomes inhibited P-gp levels measured by western blotting in dose and time-dependent manners in brain endothelial bEND.3 cells. Increased drug efflux transporters were detected in bEND.3 and astrocytes C8D1A cells, promoted by tumor necrosis factor (TNF-α) or hydrogen peroxide (H2O2). Restored accumulations of riluzole and fluorescent dye rhodamine 123 were observed in bEND.3 cells after treatments with cocktail liposomes. It indicated that inhibitory potential of co-delivery liposome system towards P-gp could mediate the transport of both P-gp substrates. Verapamil and riluzole co-loaded liposomes may be used to overcome pharmacoresistance of riluzole for improving ALS therapy.
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Affiliation(s)
- Tianzhi Yang
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, Husson University, 1 College Circle, Bangor, ME 04401, United States
| | - Laine Ferrill
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, Husson University, 1 College Circle, Bangor, ME 04401, United States
| | - Leanne Gallant
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, Husson University, 1 College Circle, Bangor, ME 04401, United States
| | - Sarah McGillicuddy
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, Husson University, 1 College Circle, Bangor, ME 04401, United States
| | - Tatiana Fernandes
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, Husson University, 1 College Circle, Bangor, ME 04401, United States
| | - Nicole Schields
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, Husson University, 1 College Circle, Bangor, ME 04401, United States
| | - Shuhua Bai
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, Husson University, 1 College Circle, Bangor, ME 04401, United States.
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Modarres HP, Janmaleki M, Novin M, Saliba J, El-Hajj F, RezayatiCharan M, Seyfoori A, Sadabadi H, Vandal M, Nguyen MD, Hasan A, Sanati-Nezhad A. In vitro models and systems for evaluating the dynamics of drug delivery to the healthy and diseased brain. J Control Release 2018; 273:108-130. [PMID: 29378233 DOI: 10.1016/j.jconrel.2018.01.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 01/22/2018] [Accepted: 01/23/2018] [Indexed: 12/12/2022]
Abstract
The blood-brain barrier (BBB) plays a crucial role in maintaining brain homeostasis and transport of drugs to the brain. The conventional animal and Transwell BBB models along with emerging microfluidic-based BBB-on-chip systems have provided fundamental functionalities of the BBB and facilitated the testing of drug delivery to the brain tissue. However, developing biomimetic and predictive BBB models capable of reasonably mimicking essential characteristics of the BBB functions is still a challenge. In addition, detailed analysis of the dynamics of drug delivery to the healthy or diseased brain requires not only biomimetic BBB tissue models but also new systems capable of monitoring the BBB microenvironment and dynamics of barrier function and delivery mechanisms. This review provides a comprehensive overview of recent advances in microengineering of BBB models with different functional complexity and mimicking capability of healthy and diseased states. It also discusses new technologies that can make the next generation of biomimetic human BBBs containing integrated biosensors for real-time monitoring the tissue microenvironment and barrier function and correlating it with the dynamics of drug delivery. Such integrated system addresses important brain drug delivery questions related to the treatment of brain diseases. We further discuss how the combination of in vitro BBB systems, computational models and nanotechnology supports for characterization of the dynamics of drug delivery to the brain.
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Affiliation(s)
- Hassan Pezeshgi Modarres
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada
| | - Mohsen Janmaleki
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada
| | - Mana Novin
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada
| | - John Saliba
- Biomedical Engineering, Department of Mechanical Engineering, Faculty of Engineering and Architecture, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Fatima El-Hajj
- Biomedical Engineering, Department of Mechanical Engineering, Faculty of Engineering and Architecture, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Mahdi RezayatiCharan
- Breast Cancer Research Center (BCRC), ACECR, Tehran, Iran; School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Amir Seyfoori
- Breast Cancer Research Center (BCRC), ACECR, Tehran, Iran; School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Hamid Sadabadi
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada
| | - Milène Vandal
- Departments of Clinical Neurosciences, Cell Biology and Anatomy, Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
| | - Minh Dang Nguyen
- Departments of Clinical Neurosciences, Cell Biology and Anatomy, Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
| | - Anwarul Hasan
- Biomedical Engineering, Department of Mechanical Engineering, Faculty of Engineering and Architecture, American University of Beirut, Beirut 1107 2020, Lebanon; Department of Mechanical and Industrial Engineering, College of Engineering, Qatar University, Doha, 2713, Qatar
| | - Amir Sanati-Nezhad
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada.
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14
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Kim SS, Im SH, Yang JY, Lee YR, Kim GR, Chae JS, Shin DS, Song JS, Ahn S, Lee BH, Woo JC, Ahn JH, Yun CS, Kim P, Kim HR, Lee KR, Bae MA. Zebrafish as a Screening Model for Testing the Permeability of Blood-Brain Barrier to Small Molecules. Zebrafish 2017; 14:322-330. [PMID: 28488933 DOI: 10.1089/zeb.2016.1392] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The objective of this study was to evaluate the permeability of small molecules into the brain via the blood-brain barrier in zebrafish and to investigate the possibility of using this animal model as a screening tool during the early stages of drug discovery. Fifteen compounds were used to understand the permeation into the brain in zebrafish and mice. The ratio of brain-to-plasma concentration was compared between the two animal models. The partition coefficient (Kp,brain), estimated using the concentration ratio at designated times (0.167, 0.25, 0.5, or 2 h) after oral administrations (per os, p.o), ranged from 0.099 to 5.68 in zebrafish and from 0.080 to 11.8 in mice. A correlation was observed between the Kp,brain values obtained from the zebrafish and mice, suggesting that zebrafish can be used to estimate Kp,brain to predict drug penetration in humans. Furthermore, in vivo transport experiments to understand the permeability glycoprotein (P-gp) transporter-mediated behavior of loperamide (LPM) in zebrafish were performed. The zebrafish, Kp,brain,30min of LPM was determined to be 0.099 ± 0.069 after dosing with LPM alone, which increased to 0.180 ± 0.115 after dosing with LPM and tariquidar (TRQ, an inhibitor of P-gp). In mouse, the Kp,brain,30min of LPM was determined to be 0.080 ± 0.004 after dosing with LPM alone and 0.237 ± 0.013 after dosing with LPM and TRQ. These findings indicate that the zebrafish could be used as an effective screening tool during the discovery stages of new drugs to estimate their distribution in the brain.
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Affiliation(s)
- Seong Soon Kim
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea
| | - So Hee Im
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea.,2 Life Science Institute , Daewoong Pharmaceutical, Yongin, Korea
| | - Jung Yoon Yang
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea
| | - Yu-Ri Lee
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea
| | - Geum Ran Kim
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea
| | - Jin Sil Chae
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea
| | - Dae-Seop Shin
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea
| | - Jin Sook Song
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea.,3 Department of Medicinal Chemistry and Pharmacology, University of Science and Technology , Daejeon, Korea
| | - Sunjoo Ahn
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea.,3 Department of Medicinal Chemistry and Pharmacology, University of Science and Technology , Daejeon, Korea
| | - Byung Hoi Lee
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea
| | - Jae Chun Woo
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea
| | - Jin Hee Ahn
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea
| | - Chang Soo Yun
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea
| | - Phiho Kim
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea
| | - Hyoung Rae Kim
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea
| | - Kyeong-Ryoon Lee
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea.,2 Life Science Institute , Daewoong Pharmaceutical, Yongin, Korea
| | - Myung Ae Bae
- 1 Bio & Drug Discovery Division, Korea Research Institute of Chemical Technology , Daejeon, Korea.,3 Department of Medicinal Chemistry and Pharmacology, University of Science and Technology , Daejeon, Korea
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15
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Li Y, Miao X, Chen T, Yi X, Wang R, Zhao H, Lee SMY, Wang X, Zheng Y. Zebrafish as a visual and dynamic model to study the transport of nanosized drug delivery systems across the biological barriers. Colloids Surf B Biointerfaces 2017; 156:227-235. [PMID: 28544957 DOI: 10.1016/j.colsurfb.2017.05.022] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 04/29/2017] [Accepted: 05/08/2017] [Indexed: 10/19/2022]
Abstract
With the wide application of nanotechnology to drug delivery systems, a simple, dynamic and visual in vivo model for high-throughput screening of novel formulations with fluorescence markers across biological barriers is desperately needed. In vitro cell culture models have been widely used, although they are far from a complimentary in vivo system. Mammalian animal models are common predictive models to study transport, but they are costly and time consuming. Zebrafish (Danio rerio), a small vertebrate model, have the potential to be developed as an "intermediate" model for quick evaluations. Based on our previously established coumarin 6 nanocrystals (C6-NCs), which have two different sizes, the present study investigates the transportation of C6-NCs across four biological barriers, including the chorion, blood brain barrier (BBB), blood retinal barrier (BRB) and gastrointestinal (GI) barrier, using zebrafish embryos and larvae as in vivo models. The biodistribution and elimination of C6 from different organs were quantified in adult zebrafish. The results showed that compared to 200nm C6-NCs, 70nm C6-NCs showed better permeability across these biological barriers. A FRET study suggested that intact C6-NCs together with the free dissolved form of C6 were absorbed into the larval zebrafish. More C6 was accumulated in different organs after incubation with small sized NCs via lipid raft-mediated endocytosis in adult zebrafish, which is consistent with the findings from in vitro cell monolayers and the zebrafish larvae model. C6-NCs could be gradually eliminated in each organ over time. This study demonstrated the successful application of zebrafish as a simple and dynamic model to simultaneously assess the transport of nanosized drug delivery systems across several biological barriers and biodistribution in different organs, especially in the brain, which could be used for central nervous system (CNS) drug and delivery system screening.
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Affiliation(s)
- Ye Li
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
| | - Xiaoqing Miao
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
| | - Tongkai Chen
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
| | - Xiang Yi
- Division of Molecular Pharmaceutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27516, United States
| | - Ruibing Wang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
| | - Haitao Zhao
- Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Simon Ming-Yuen Lee
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
| | - Xueqing Wang
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Ying Zheng
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China.
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16
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Silva-Santisteban A, Steinke N, Johnston AJ, Ruiz GN, Carlos Pardo L, McLain SE. On the structure of prilocaine in aqueous and amphiphilic solutions. Phys Chem Chem Phys 2017; 19:12665-12673. [DOI: 10.1039/c7cp01723e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The solvation of prilocaine has been investigated in pure water and in amphiphilic solutions using a combination of neutron diffraction and simulations.
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Affiliation(s)
- Alvaro Silva-Santisteban
- Department of Biochemistry
- University of Oxford
- Oxford OX1 3QU
- UK
- Departament de Física i Enginyeria Nuclear & Barcelona Research Center in Multiscale Science and Engineering
| | - Nicola Steinke
- Department of Biochemistry
- University of Oxford
- Oxford OX1 3QU
- UK
| | | | - Guadalupe N. Ruiz
- Departament de Física i Enginyeria Nuclear & Barcelona Research Center in Multiscale Science and Engineering
- Universitat Politècnica de Catalunya
- 08019 Barcelona
- Spain
| | - Luis Carlos Pardo
- Departament de Física i Enginyeria Nuclear & Barcelona Research Center in Multiscale Science and Engineering
- Universitat Politècnica de Catalunya
- 08019 Barcelona
- Spain
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17
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Yang T, Fogarty B, LaForge B, Aziz S, Pham T, Lai L, Bai S. Delivery of Small Interfering RNA to Inhibit Vascular Endothelial Growth Factor in Zebrafish Using Natural Brain Endothelia Cell-Secreted Exosome Nanovesicles for the Treatment of Brain Cancer. AAPS JOURNAL 2016; 19:475-486. [PMID: 27882487 DOI: 10.1208/s12248-016-0015-y] [Citation(s) in RCA: 137] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 11/07/2016] [Indexed: 01/08/2023]
Abstract
Although small interfering RNA (siRNA) holds great therapeutic promise, its delivery to the disease site remains a paramount obstacle. In this study, we tested whether brain endothelial cell-derived exosomes could deliver siRNA across the blood-brain barrier (BBB) in zebrafish. Natural exosomes were isolated from brain endothelial bEND.3 cell culture media and vascular endothelial growth factor (VEGF) siRNA was loaded in exosomes with the assistance of a transfection reagent. While fluorescence-activated cell flow cytometry and immunocytochemistry staining studies indicated that wild-type exosomes significantly increased the uptake of fluorescence-labeled siRNA in the autologous brain endothelial cells, decreased fluorescence intensity was observed in the cells treated with the tetraspanin CD63 antibody-blocked exosome-delivered formulation (p < 0.05). In the transport study, exosomes also enhanced the permeability of rhodamine 123 in a co-cultured monolayer of brain endothelial bEND.3 cell and astrocyte. Inhibition at the expression of VEGF RNA and protein levels was observed in glioblastoma-astrocytoma U-87 MG cells treated with exosome-delivered siRNAs. Imaging results showed that exosome delivered more siRNAs across the BBB in Tg(fli1:GFP) zebrafish. In a xenotransplanted brain tumor model, exosome-delivered VEGF siRNAs decreased the fluorescence intensity of labeled cancer cells in the brain of zebrafish. Brain endothelial cell-derived exosomes could be potentially used as a natural carrier for the brain delivery of exogenous siRNA.
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Affiliation(s)
- Tianzhi Yang
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, Husson University, Bangor, Maine, 04401, USA
| | - Brittany Fogarty
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, Husson University, Bangor, Maine, 04401, USA
| | - Bret LaForge
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, Husson University, Bangor, Maine, 04401, USA
| | - Salma Aziz
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, Husson University, Bangor, Maine, 04401, USA
| | - Thuy Pham
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, Husson University, Bangor, Maine, 04401, USA
| | - Leanne Lai
- Department of Sociobehavioral and Administrative Pharmacy, College of Pharmacy, Nova Southeastern University, Ft. Lauderdale, Florida, 33328, USA
| | - Shuhua Bai
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, Husson University, Bangor, Maine, 04401, USA.
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18
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Qosa H, Mohamed LA, Al Rihani SB, Batarseh YS, Duong QV, Keller JN, Kaddoumi A. High-Throughput Screening for Identification of Blood-Brain Barrier Integrity Enhancers: A Drug Repurposing Opportunity to Rectify Vascular Amyloid Toxicity. J Alzheimers Dis 2016; 53:1499-516. [PMID: 27392852 PMCID: PMC4992409 DOI: 10.3233/jad-151179] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The blood-brain barrier (BBB) is a dynamic interface that maintains brain homeostasis and protects it from free entry of chemicals, toxins, and drugs. The barrier function of the BBB is maintained mainly by capillary endothelial cells that physically separate brain from blood. Several neurological diseases, such as Alzheimer's disease (AD), are known to disrupt BBB integrity. In this study, a high-throughput screening (HTS) was developed to identify drugs that rectify/protect BBB integrity from vascular amyloid toxicity associated with AD progression. Assessing Lucifer Yellow permeation across in-vitro BBB model composed from mouse brain endothelial cells (bEnd3) grown on 96-well plate inserts was used to screen 1280 compounds of Sigma LOPAC®1280 library for modulators of bEnd3 monolayer integrity. HTS identified 62 compounds as disruptors, and 50 compounds as enhancers of the endothelial barrier integrity. From these 50 enhancers, 7 FDA approved drugs were identified with EC50 values ranging from 0.76-4.56 μM. Of these 7 drugs, 5 were able to protect bEnd3-based BBB model integrity against amyloid toxicity. Furthermore, to test the translational potential to humans, the 7 drugs were tested for their ability to rectify the disruptive effect of Aβ in the human endothelial cell line hCMEC/D3. Only 3 (etodolac, granisetron, and beclomethasone) out of the 5 effective drugs in the bEnd3-based BBB model demonstrated a promising effect to protect the hCMEC/D3-based BBB model integrity. These drugs are compelling candidates for repurposing as therapeutic agents that could rectify dysfunctional BBB associated with AD.
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Affiliation(s)
- Hisham Qosa
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, USA
| | - Loqman A. Mohamed
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, USA
| | - Sweilem B. Al Rihani
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, USA
| | - Yazan S. Batarseh
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, USA
| | - Quoc-Viet Duong
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, USA
| | - Jeffrey N. Keller
- Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, LA, USA
| | - Amal Kaddoumi
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, USA
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19
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Kalashnikova I, Albekairi N, Ali S, Al Enazy S, Rytting E. Cell Culture Models for Drug Transport Studies. Drug Deliv 2016. [DOI: 10.1002/9781118833322.ch7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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20
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Johnston AJ, Busch S, Pardo LC, Callear SK, Biggin PC, McLain SE. On the atomic structure of cocaine in solution. Phys Chem Chem Phys 2016; 18:991-9. [DOI: 10.1039/c5cp06090g] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A combination of neutron diffraction and computation has been used to investigate the atomic scale structure of cocaine in aqueous solutions.
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Affiliation(s)
| | - Sebastian Busch
- German Engineering Materials Science Centre (GEMS) at Heinz Maier-Leibnitz Zentrum (MLZ)
- Helmholtz-Zentrum Geesthacht GmbH
- 85747 Garching bei München
- Germany
| | - Luis Carlos Pardo
- Departament de Física i Enginyeria Nuclear
- Escola Tècnica Superior d'Enginyeria Industrial de Barcelona (ETSEIB)
- Universitat Politècnica de Catalunya
- 08028 Barcelona
- Spain
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21
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Abstract
The blood-brain barrier (BBB) is a microvascular unit which selectively regulates the permeability of drugs to the brain. With the rise in CNS drug targets and diseases, there is a need to be able to accurately predict a priori which compounds in a company database should be pursued for favorable properties. In this review, we will explore the different computational tools available today, as well as underpin these to the experimental methods used to determine BBB permeability. These include in vitro models and the in vivo models that yield the dataset we use to generate predictive models. Understanding of how these models were experimentally derived determines our accurate and predicted use for determining a balance between activity and BBB distribution.
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22
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Huntley MA, Bien-Ly N, Daneman R, Watts RJ. Dissecting gene expression at the blood-brain barrier. Front Neurosci 2014; 8:355. [PMID: 25414634 PMCID: PMC4222230 DOI: 10.3389/fnins.2014.00355] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 10/15/2014] [Indexed: 12/21/2022] Open
Abstract
The availability of genome-wide expression data for the blood-brain barrier is an invaluable resource that has recently enabled the discovery of several genes and pathways involved in the development and maintenance of the blood-brain barrier, particularly in rodent models. The broad distribution of published data sets represents a viable starting point for the molecular dissection of the blood-brain barrier and will further direct the discovery of novel mechanisms of blood-brain barrier formation and function. Technical advances in purifying brain endothelial cells, the key cell that forms the critical barrier, have allowed for greater specificity in gene expression comparisons with other central nervous system cell types, and more systematic characterizations of the molecular composition of the blood-brain barrier. Nevertheless, our understanding of how the blood-brain barrier changes during aging and disease is underrepresented. Blood-brain barrier data sets from a wider range of experimental paradigms and species, including invertebrates and primates, would be invaluable for investigating the function and evolution of the blood-brain barrier. Newer technologies in gene expression profiling, such as RNA-sequencing, now allow for finer resolution of transcriptomic changes, including isoform specificity and RNA-editing. As our field continues to utilize more advanced expression profiling in its ongoing efforts to elucidate the blood-brain barrier, including in disease and drug delivery, we will continue to see rapid advances in our understanding of the molecular mediators of barrier biology. We predict that the recently published data sets, combined with forthcoming genomic and proteomic blood-brain barrier data sets, will continue to fuel the molecular genetic revolution of blood-brain barrier biology.
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Affiliation(s)
- Melanie A Huntley
- Department of Bioinformatics and Computational Biology, Genentech Inc. South San Francisco, CA, USA
| | - Nga Bien-Ly
- Department of Neuroscience, Genentech Inc. South San Francisco, CA, USA
| | - Richard Daneman
- Department of Pharmacology, University of California, San Diego La Jolla, CA, USA
| | - Ryan J Watts
- Department of Neuroscience, Genentech Inc. South San Francisco, CA, USA
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23
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Tajes M, Ramos-Fernández E, Weng-Jiang X, Bosch-Morató M, Guivernau B, Eraso-Pichot A, Salvador B, Fernàndez-Busquets X, Roquer J, Muñoz FJ. The blood-brain barrier: structure, function and therapeutic approaches to cross it. Mol Membr Biol 2014; 31:152-67. [PMID: 25046533 DOI: 10.3109/09687688.2014.937468] [Citation(s) in RCA: 172] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The blood-brain barrier (BBB) is constituted by a specialized vascular endothelium that interacts directly with astrocytes, neurons and pericytes. It protects the brain from the molecules of the systemic circulation but it has to be overcome for the proper treatment of brain cancer, psychiatric disorders or neurodegenerative diseases, which are dramatically increasing as the population ages. In the present work we have revised the current knowledge on the cellular structure of the BBB and the different procedures utilized currently and those proposed to cross it. Chemical modifications of the drugs, such as increasing their lipophilicity, turn them more prone to be internalized in the brain. Other mechanisms are the use of molecular tools to bind the drugs such as small immunoglobulins, liposomes or nanoparticles that will act as Trojan Horses favoring the drug delivery in brain. This fusion of the classical pharmacology with nanotechnology has opened a wide field to many different approaches with promising results to hypothesize that BBB will not be a major problem for the new generation of neuroactive drugs. The present review provides an overview of all state-of-the-art of the BBB structure and function, as well as of the classic strategies and these appeared in recent years to deliver drugs into the brain for the treatment of Central Nervous System (CNS) diseases.
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Affiliation(s)
- Marta Tajes
- Laboratory of Molecular Physiology and Channelopathies, Department of Experimental and Health Sciences, Universitat Pompeu Fabra (UPF) , Barcelona, Spain
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24
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Mikitsh JL, Chacko AM. Pathways for small molecule delivery to the central nervous system across the blood-brain barrier. PERSPECTIVES IN MEDICINAL CHEMISTRY 2014; 6:11-24. [PMID: 24963272 PMCID: PMC4064947 DOI: 10.4137/pmc.s13384] [Citation(s) in RCA: 123] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 04/29/2014] [Accepted: 04/29/2014] [Indexed: 01/04/2023]
Abstract
The treatment of central nervous system (CNS) disease has long been difficult due to the ineffectiveness of drug delivery across the blood-brain barrier (BBB). This review summarizes important concepts of the BBB in normal versus pathophysiology and how this physical, enzymatic, and efflux barrier provides necessary protection to the CNS during drug delivery, and consequently treatment challenging. Small molecules account for the vast majority of available CNS drugs primarily due to their ability to penetrate the phospholipid membrane of the BBB by passive or carrier-mediated mechanisms. Physiochemical and biological factors relevant for designing small molecules with optimal capabilities for BBB permeability are discussed, as well as the most promising classes of transporters suitable for small-molecule drug delivery. Clinically translatable imaging methodologies for detecting and quantifying drug uptake and targeting in the brain are discussed as a means of further understanding and refining delivery parameters for both drugs and imaging probes in preclinical and clinical domains. This information can be used as a guide to design drugs with preserved drug action and better delivery profiles for improved treatment outcomes over existing therapeutic approaches.
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Affiliation(s)
- John L Mikitsh
- Department of Radiology, Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ann-Marie Chacko
- Department of Radiology, Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Center for Targeted Therapeutics and Translational Nanomedicine, Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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25
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Andersson O, Badisco L, Hansen AH, Hansen SH, Hellman K, Nielsen PA, Olsen LR, Verdonck R, Abbott NJ, Vanden Broeck J, Andersson G. Characterization of a novel brain barrier ex vivo insect-based P-glycoprotein screening model. Pharmacol Res Perspect 2014; 2:e00050. [PMID: 25505597 PMCID: PMC4186439 DOI: 10.1002/prp2.50] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 04/02/2014] [Accepted: 04/03/2014] [Indexed: 01/16/2023] Open
Abstract
In earlier studies insects were proposed as suitable models for vertebrate blood–brain barrier (BBB) permeability prediction and useful in early drug discovery. Here we provide transcriptome and functional data demonstrating the presence of a P-glycoprotein (Pgp) efflux transporter in the brain barrier of the desert locust (Schistocerca gregaria). In an in vivo study on the locust, we found an increased uptake of the two well-known Pgp substrates, rhodamine 123 and loperamide after co-administration with the Pgp inhibitors cyclosporine A or verapamil. Furthermore, ex vivo studies on isolated locust brains demonstrated differences in permeation of high and low permeability compounds. The vertebrate Pgp inhibitor verapamil did not affect the uptake of passively diffusing compounds but significantly increased the brain uptake of Pgp substrates in the ex vivo model. In addition, studies at 2°C and 30°C showed differences in brain uptake between Pgp-effluxed and passively diffusing compounds. The transcriptome data show a high degree of sequence identity of the locust Pgp transporter protein sequences to the human Pgp sequence (37%), as well as the presence of conserved domains. As in vertebrates, the locust brain–barrier function is morphologically confined to one specific cell layer and by using a whole-brain ex vivo drug exposure technique our locust model may retain the major cues that maintain and modulate the physiological function of the brain barrier. We show that the locust model has the potential to act as a robust and convenient model for assessing BBB permeability in early drug discovery.
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Affiliation(s)
- Olga Andersson
- EntomoPharm, R&D Medicon Village, S-223 81, Lund, Sweden
| | - Liesbeth Badisco
- Department of Animal Physiology and Neurobiology, Katholieke Universiteit Leuven Leuven, Belgium
| | | | - Steen Honoré Hansen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen DK-2100, Copenhagen, Denmark
| | - Karin Hellman
- EntomoPharm, R&D Medicon Village, S-223 81, Lund, Sweden
| | | | - Line Rørbæk Olsen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen DK-2100, Copenhagen, Denmark
| | - Rik Verdonck
- Department of Animal Physiology and Neurobiology, Katholieke Universiteit Leuven Leuven, Belgium
| | - N Joan Abbott
- BBB Group, Institute of Pharmaceutical Science, King's College London Franklin Wilkins Building, London, SE1 9NH, United Kingdom
| | - Jozef Vanden Broeck
- Department of Animal Physiology and Neurobiology, Katholieke Universiteit Leuven Leuven, Belgium
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Olsen LR, Gabel-Jensen C, Nielsen PA, Hansen SH, Badolo L. Identification of a Functional Homolog of the Mammalian CYP3A4 in Locusts. Drug Metab Dispos 2014; 42:1153-62. [DOI: 10.1124/dmd.114.057430] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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Obermeier B, Daneman R, Ransohoff RM. Development, maintenance and disruption of the blood-brain barrier. Nat Med 2013; 19:1584-96. [PMID: 24309662 DOI: 10.1038/nm.3407] [Citation(s) in RCA: 1593] [Impact Index Per Article: 144.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 10/22/2013] [Indexed: 01/01/2023]
Abstract
The interface between the blood circulation and the neural tissue features unique characteristics that are encompassed by the term 'blood-brain barrier' (BBB). The main functions of this barrier, namely maintenance of brain homeostasis, regulation of influx and efflux transport, and protection from harm, are determined by its specialized multicellular structure. Every constituent cell type makes an indispensable contribution to the BBB's integrity. But if one member of the BBB fails, and as a result the barrier breaks down, there can be dramatic consequences and neuroinflammation and neurodegeneration can occur. In this Review, we highlight recently gained mechanistic insights into the development and maintenance of the BBB. We then discuss how BBB disruption can cause or contribute to neurological disease. Finally, we examine how this knowledge can be used to explore new possibilities for BBB repair.
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Affiliation(s)
- Birgit Obermeier
- Neuroinflammation Research Center, Department of Neuroscience, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
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Palmer AM, Alavijeh MS. Overview of experimental models of the blood-brain barrier in CNS drug discovery. ACTA ACUST UNITED AC 2013; 62:7.15.1-7.15.30. [PMID: 24510719 DOI: 10.1002/0471141755.ph0715s62] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The blood-brain barrier (BBB) is a physical and metabolic entity that isolates the brain from the systemic circulation. The barrier consists of tight junctions between endothelial cells that contain egress transporters and catabolic enzymes. To cross the BBB, a drug must possess the appropriate physicochemical properties to achieve a sufficient time-concentration profile in brain interstitial fluid (ISF). In this overview, we review techniques to measure BBB permeation, which is evidenced by the free concentration of compound in brain ISF over time. We consider a number of measurement techniques, including in vivo microdialysis and brain receptor occupancy following perfusion. Consideration is also given to the endothelial and nonendothelial cell systems used to assess both the BBB permeation of a test compound and its interactions with egress transporters, and computer models employed for predicting passive permeation and the probability of interactions with BBB transporters.
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Design of brain imaging agents for positron emission tomography: do large bioconjugates provide an opportunity for in vivo brain imaging? Future Med Chem 2013; 5:1621-34. [PMID: 24047268 DOI: 10.4155/fmc.13.128] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The development of brain imaging agents for positron emission tomography and other in vivo imaging modalities mostly relies on small compounds of low MW as a result of the restricted transport of larger molecules, such as peptides and proteins, across the blood–brain barrier. Besides passive transport, only a few active carrier mechanisms, such as glucose transporters and amino acid transporters, have so far been exploited to mediate the accumulation of imaging probes in the brain. An important question for the future is whether some of the abundant active carrier systems located at the blood–brain barrier can be used to shuttle potential, but non-crossing, imaging agents into the brain. What are the biological and chemical constrictions toward such bioconjugates and is it worthwhile to persue such a delivery strategy?
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Nanotechnology-Based Drug Delivery Systems for Targeting, Imaging and Diagnosis of Neurodegenerative Diseases. Pharm Res 2013; 30:2499-511. [DOI: 10.1007/s11095-013-1156-7] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2012] [Accepted: 07/22/2013] [Indexed: 12/26/2022]
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Andersson O, Hansen SH, Hellman K, Olsen LR, Andersson G, Badolo L, Svenstrup N, Nielsen PA. The grasshopper: a novel model for assessing vertebrate brain uptake. J Pharmacol Exp Ther 2013; 346:211-8. [PMID: 23671124 DOI: 10.1124/jpet.113.205476] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The aim of the present study was to develop a blood-brain barrier (BBB) permeability model that is applicable in the drug discovery phase. The BBB ensures proper neural function, but it restricts many drugs from entering the brain, and this complicates the development of new drugs against central nervous system diseases. Many in vitro models have been developed to predict BBB permeability, but the permeability characteristics of the human BBB are notoriously complex and hard to predict. Consequently, one single suitable BBB permeability screening model, which is generally applicable in the early drug discovery phase, does not yet exist. A new refined ex vivo insect-based BBB screening model that uses an intact, viable whole brain under controlled in vitro-like exposure conditions is presented. This model uses intact brains from desert locusts, which are placed in a well containing the compound solubilized in an insect buffer. After a limited time, the brain is removed and the compound concentration in the brain is measured by conventional liquid chromatography-mass spectrometry. The data presented here include 25 known drugs, and the data show that the ex vivo insect model can be used to measure the brain uptake over the hemolymph-brain barrier of drugs and that the brain uptake shows linear correlation with in situ perfusion data obtained in vertebrates. Moreover, this study shows that the insect ex vivo model is able to identify P-glycoprotein (Pgp) substrates, and the model allows differentiation between low-permeability compounds and compounds that are Pgp substrates.
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Kell DB. Finding novel pharmaceuticals in the systems biology era using multiple effective drug targets, phenotypic screening and knowledge of transporters: where drug discovery went wrong and how to fix it. FEBS J 2013; 280:5957-80. [PMID: 23552054 DOI: 10.1111/febs.12268] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2013] [Revised: 03/20/2013] [Accepted: 03/26/2013] [Indexed: 12/16/2022]
Abstract
Despite the sequencing of the human genome, the rate of innovative and successful drug discovery in the pharmaceutical industry has continued to decrease. Leaving aside regulatory matters, the fundamental and interlinked intellectual issues proposed to be largely responsible for this are: (a) the move from 'function-first' to 'target-first' methods of screening and drug discovery; (b) the belief that successful drugs should and do interact solely with single, individual targets, despite natural evolution's selection for biochemical networks that are robust to individual parameter changes; (c) an over-reliance on the rule-of-5 to constrain biophysical and chemical properties of drug libraries; (d) the general abandoning of natural products that do not obey the rule-of-5; (e) an incorrect belief that drugs diffuse passively into (and presumably out of) cells across the bilayers portions of membranes, according to their lipophilicity; (f) a widespread failure to recognize the overwhelmingly important role of proteinaceous transporters, as well as their expression profiles, in determining drug distribution in and between different tissues and individual patients; and (g) the general failure to use engineering principles to model biology in parallel with performing 'wet' experiments, such that 'what if?' experiments can be performed in silico to assess the likely success of any strategy. These facts/ideas are illustrated with a reasonably extensive literature review. Success in turning round drug discovery consequently requires: (a) decent systems biology models of human biochemical networks; (b) the use of these (iteratively with experiments) to model how drugs need to interact with multiple targets to have substantive effects on the phenotype; (c) the adoption of polypharmacology and/or cocktails of drugs as a desirable goal in itself; (d) the incorporation of drug transporters into systems biology models, en route to full and multiscale systems biology models that incorporate drug absorption, distribution, metabolism and excretion; (e) a return to 'function-first' or phenotypic screening; and (f) novel methods for inferring modes of action by measuring the properties on system variables at all levels of the 'omes. Such a strategy offers the opportunity of achieving a state where we can hope to predict biological processes and the effect of pharmaceutical agents upon them. Consequently, this should both lower attrition rates and raise the rates of discovery of effective drugs substantially.
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Affiliation(s)
- Douglas B Kell
- School of Chemistry, The University of Manchester, UK; Manchester Institute of Biotechnology, The University of Manchester, UK
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Hammarlund-Udenaes M. In Vivo Approaches to Assessing the Blood–Brain Barrier. TOPICS IN MEDICINAL CHEMISTRY 2013. [DOI: 10.1007/7355_2013_27] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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The promiscuous binding of pharmaceutical drugs and their transporter-mediated uptake into cells: what we (need to) know and how we can do so. Drug Discov Today 2012. [PMID: 23207804 DOI: 10.1016/j.drudis.2012.11.008] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A recent paper in this journal sought to counter evidence for the role of transport proteins in effecting drug uptake into cells, and questions that transporters can recognize drug molecules in addition to their endogenous substrates. However, there is abundant evidence that both drugs and proteins are highly promiscuous. Most proteins bind to many drugs and most drugs bind to multiple proteins (on average more than six), including transporters (mutations in these can determine resistance); most drugs are known to recognise at least one transporter. In this response, we alert readers to the relevant evidence that exists or is required. This needs to be acquired in cells that contain the relevant proteins, and we highlight an experimental system for simultaneous genome-wide assessment of carrier-mediated uptake in a eukaryotic cell (yeast).
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