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Conq J, Joudiou N, Préat V, Gallez B. Exploring the Impact of Irradiation on Glioblastoma Blood-Brain-Barrier Permeability: Insights from Dynamic-Contrast-Enhanced-MRI and Histological Analysis. Biomedicines 2024; 12:1091. [PMID: 38791053 PMCID: PMC11118616 DOI: 10.3390/biomedicines12051091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Revised: 04/26/2024] [Accepted: 05/10/2024] [Indexed: 05/26/2024] Open
Abstract
(1) Background: Glioblastoma (GB) presents a formidable challenge in neuro-oncology due to its aggressive nature, limited treatment options, and poor prognosis. The blood-brain barrier (BBB) complicates treatment by hindering drug delivery to the tumor site, particularly to the infiltrative cells in the margin of the tumor, which are mainly responsible for tumor recurrence. Innovative strategies are therefore needed to enhance drug delivery in the margins of the tumor. This study explores whether irradiation can enhance BBB permeability by assessing hemodynamic changes and the distribution of contrast agents in the core and the margins of GB tumors. (2) Methods: Mice grafted with U-87MG cells were exposed to increasing irradiation doses. The distribution of contrast agents and hemodynamic parameters was evaluated using both non-invasive magnetic resonance imaging (MRI) techniques with gadolinium-DOTA as a contrast agent and invasive histological analysis with Evans blue, a fluorescent vascular leakage marker. Diffusion-MRI was also used to assess cytotoxic effects. (3) Results: The histological study revealed a complex dose-dependent effect of irradiation on BBB integrity, with increased vascular leakage at 5 Gy but reduced leakage at higher doses (10 and 15 Gy). However, there was no significant increase in the diffusion of Gd-DOTA outside the tumor area by MRI. (4) Conclusions: The increase in BBB permeability could be an interesting approach to enhance drug delivery in glioblastoma margins for low irradiation doses. In this model, DCE-MRI analysis was of limited value in assessing the BBB opening in glioblastoma after irradiation.
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Affiliation(s)
- Jérôme Conq
- Biomedical Magnetic Resonance Research Group, Louvain Drug Research Institute (LDRI), Université Catholique de Louvain (UCLouvain), 1200 Brussels, Belgium;
- Advanced Drug Delivery and Biomaterials Research Group, Louvain Drug Research Institute (LDRI), Université Catholique de Louvain (UCLouvain), 1200 Brussels, Belgium;
| | - Nicolas Joudiou
- Nuclear and Electron Spin Technologies (NEST) Platform, Louvain Drug Research Institute (LDRI), Université Catholique de Louvain (UCLouvain), 1200 Brussels, Belgium;
| | - Véronique Préat
- Advanced Drug Delivery and Biomaterials Research Group, Louvain Drug Research Institute (LDRI), Université Catholique de Louvain (UCLouvain), 1200 Brussels, Belgium;
| | - Bernard Gallez
- Biomedical Magnetic Resonance Research Group, Louvain Drug Research Institute (LDRI), Université Catholique de Louvain (UCLouvain), 1200 Brussels, Belgium;
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Conq J, Joudiou N, Ucakar B, Vanvarenberg K, Préat V, Gallez B. Assessment of Hyperosmolar Blood-Brain Barrier Opening in Glioblastoma via Histology with Evans Blue and DCE-MRI. Biomedicines 2023; 11:1957. [PMID: 37509598 PMCID: PMC10377677 DOI: 10.3390/biomedicines11071957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 07/02/2023] [Accepted: 07/07/2023] [Indexed: 07/30/2023] Open
Abstract
BACKGROUND While the blood-brain barrier (BBB) is often compromised in glioblastoma (GB), the perfusion and consequent delivery of drugs are highly heterogeneous. Moreover, the accessibility of drugs is largely impaired in the margins of the tumor and for infiltrating cells at the origin of tumor recurrence. In this work, we evaluate the value of methods to assess hemodynamic changes induced by a hyperosmolar shock in the core and the margins of a tumor in a GB model. METHODS Osmotic shock was induced with an intracarotid infusion of a hypertonic solution of mannitol in mice grafted with U87-MG cells. The distribution of fluorescent dye (Evans blue) within the brain was assessed via histology. Dynamic contrast-enhanced (DCE)-MRI with an injection of Gadolinium-DOTA as the contrast agent was also used to evaluate the effect on hemodynamic parameters and the diffusion of the contrast agent outside of the tumor area. RESULTS The histological study revealed that the fluorescent dye diffused much more largely outside of the tumor area after osmotic shock than in control tumors. However, the study of tumor hemodynamic parameters via DCE-MRI did not reveal any change in the permeability of the BBB, whatever the studied MRI parameter. CONCLUSIONS The use of hypertonic mannitol infusion seems to be a promising method to increase the delivery of compounds in the margins of GB. Nevertheless, the DCE-MRI analysis method using gadolinium-DOTA as a contrast agent seems of limited value for determining the efficacy of opening the BBB in GB after osmotic shock.
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Affiliation(s)
- Jérôme Conq
- UCLouvain, Louvain Drug Research Institute (LDRI), Biomedical Magnetic Resonance Research Group, 1200 Brussels, Belgium
- UCLouvain, Louvain Drug Research Institute (LDRI), Advanced Drug Delivery and Biomaterials Research Group, 1200 Brussels, Belgium
| | - Nicolas Joudiou
- UCLouvain, Louvain Drug Research Institute (LDRI), Nuclear and Electron Spin Technologies (NEST) Platform, 1200 Brussels, Belgium
| | - Bernard Ucakar
- UCLouvain, Louvain Drug Research Institute (LDRI), Advanced Drug Delivery and Biomaterials Research Group, 1200 Brussels, Belgium
| | - Kevin Vanvarenberg
- UCLouvain, Louvain Drug Research Institute (LDRI), Advanced Drug Delivery and Biomaterials Research Group, 1200 Brussels, Belgium
| | - Véronique Préat
- UCLouvain, Louvain Drug Research Institute (LDRI), Advanced Drug Delivery and Biomaterials Research Group, 1200 Brussels, Belgium
| | - Bernard Gallez
- UCLouvain, Louvain Drug Research Institute (LDRI), Biomedical Magnetic Resonance Research Group, 1200 Brussels, Belgium
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Iorio-Morin C, Gahide G, Morin C, Vanderweyen D, Roy MA, St-Pierre I, Massicotte-Tisluck K, Fortin D. Management of Primary Central Nervous System Lymphoma Using Intra-Arterial Chemotherapy With Osmotic Blood-Brain Barrier Disruption: Retrospective Analysis of the Sherbrooke Cohort. Front Oncol 2021; 10:543648. [PMID: 33552946 PMCID: PMC7855856 DOI: 10.3389/fonc.2020.543648] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 11/25/2020] [Indexed: 12/16/2022] Open
Abstract
Background Primary central nervous system lymphomas (PCNSL) are rare and aggressive CNS tumors. Current management involves high-dose methotrexate (HD-MTX) typically administered intravenously (IV), despite the existence of the blood-brain barrier (BBB), which significantly decreases its bioavailability. Cerebral intra-arterial chemotherapy (CIAC) coupled with osmotic BBB disruption (OBBBD) can theoretically circumvent this issue. Methods We performed a retrospective analysis of patients with newly diagnosed PCNSL treated with HD-MTX-based CIAC+OBBBD at our center between November 1999 and May 2018. OBBBD was achieved using a 25% mannitol intra-arterial infusion. Patients were followed clinically and radiologically every month until death or remission. Demographics, clinical and outcome data were collected from the medical record. All imaging studies were reviewed for evidence of complication and outcome assessment. Kaplan-Meier analyses were used to compute remission, progression-free survival (PFS) as well as overall survival times. Subgroup analyses were performed using the log rank test. Results Forty-four patients were included in the cohort. Median follow-up was 38 months. Complete response was achieved in 34 patients (79%) at a median of 7.3 months. Actuarial median survival and PFS were 45 months and 24 months, respectively. Age, ECOG and lesion location did not impact outcome. Complications included thrombocytopenia (39%), neutropenia (20%), anemia (5%), seizures (11%), stroke (2%), and others (20%). Conclusion CIAC using HD-MTX-based protocols with OBBBD is a safe and well-tolerated procedure for the management of PCNSL. Our data suggests better PFS and survival outcomes compared to IV protocols with less hematologic toxicity and good tolerability, especially in the elderly.
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Affiliation(s)
- Christian Iorio-Morin
- Division of Neurosurgery, Department of Surgery, Université de Sherbrooke, Centre de recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada
| | - Gérald Gahide
- Department of Diagnostic Radiology, Université de Sherbrooke, Centre de recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada
| | - Christophe Morin
- Division of Neurosurgery, Department of Surgery, Université de Sherbrooke, Centre de recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada
| | - Davy Vanderweyen
- Division of Neurosurgery, Department of Surgery, Université de Sherbrooke, Centre de recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada
| | - Marie-André Roy
- Division of Neurosurgery, Department of Surgery, Université de Sherbrooke, Centre de recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada
| | - Isabelle St-Pierre
- Division of Neurosurgery, Department of Surgery, Université de Sherbrooke, Centre de recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada
| | - Karine Massicotte-Tisluck
- Department of Diagnostic Radiology, Université de Sherbrooke, Centre de recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada
| | - David Fortin
- Division of Neurosurgery, Department of Surgery, Université de Sherbrooke, Centre de recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, Canada
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Liotta EM, Karvellas CJ, Kim M, Batra A, Naidech A, Prabhakaran S, Sorond FA, Kimberly WT, Maas MB. Serum osmolality, cerebrospinal fluid specific gravity and overt hepatic encephalopathy severity in patients with liver failure. Liver Int 2020; 40:1977-1986. [PMID: 32020734 PMCID: PMC7398828 DOI: 10.1111/liv.14400] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 01/09/2020] [Accepted: 01/24/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIMS Hepatic encephalopathy (HE) is a leading contributor to morbidity in liver disease. While hyperammonaemia plays a key role, the mechanisms of cerebral toxicity are unclear. We hypothesized that serum hyperosmolality contributes to HE during acute (ALF) and acute-on-chronic liver failure (ACLF) through mechanisms that affect the water and solute composition of the cerebral environment. METHODS We performed a retrospective analysis of serum osmolality, cerebral spinal fluid (CSF) solute density (specific gravity, determined from computed tomography attenuation) and clinical HE severity (Glasgow Coma Score [GCS]) at the time of intensive care admission in a prospectively identified cohort of liver failure patients with overt HE. RESULTS Seventy-three patients (39 ALF and 34 ACLF) were included, of whom 28 (38%) were comatose. Serum osmolality (303.9 ± 15.4 mOsm/kg) was elevated despite normal serum sodium (136.6 ± 6.3 mEq/L). Increased osmolality was independently associated with more severe encephalopathy (ordinal adjusted OR 0.26 [95% CI 0.22, 0.31] for higher GCS per standard deviation increase in osmolality) and lower CSF-specific gravity (linear adjusted β = -0.039 [95% CI -0.069, -0.009] Hounsfield unit per 1 mOsm/kg). CONCLUSIONS In the context of related research, these data suggest that hyperosmolality increases brain exposure to metabolic toxins by blood-brain barrier alteration and may be a unique therapeutic target.
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Affiliation(s)
- Eric M. Liotta
- Northwestern University, Feinberg School of Medicine, Division of Stroke and Neurocritical Care
| | | | - Minjee Kim
- Northwestern University, Feinberg School of Medicine, Division of Stroke and Neurocritical Care
| | - Ayush Batra
- Northwestern University, Feinberg School of Medicine, Division of Stroke and Neurocritical Care
| | - Andrew Naidech
- Northwestern University, Feinberg School of Medicine, Division of Stroke and Neurocritical Care
| | | | - Farzaneh A. Sorond
- Northwestern University, Feinberg School of Medicine, Division of Stroke and Neurocritical Care
| | | | - Matthew B. Maas
- Northwestern University, Feinberg School of Medicine, Division of Stroke and Neurocritical Care
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Liotta EM, Kimberly WT. Cerebral edema and liver disease: Classic perspectives and contemporary hypotheses on mechanism. Neurosci Lett 2020; 721:134818. [PMID: 32035166 DOI: 10.1016/j.neulet.2020.134818] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 02/01/2020] [Accepted: 02/03/2020] [Indexed: 02/07/2023]
Abstract
Liver disease is a growing public health concern. Hepatic encephalopathy, the syndrome of brain dysfunction secondary to liver disease, is a frequent complication of both acute and chronic liver disease and cerebral edema (CE) is a key feature. While altered ammonia metabolism is a key contributor to hepatic encephalopathy and CE in liver disease, there is a growing appreciation that additional mechanisms contribute to CE. In this review we will begin by presenting three classic perspectives that form a foundation for a discussion of CE in liver disease: 1) CE is unique to acute liver failure, 2) CE in liver disease is only cytotoxic, and 3) CE in liver disease is primarily an osmotically mediated consequence of ammonia and glutamine metabolism. We will present each classic perspective along with more recent observations that call in to question that classic perspective. After highlighting these areas of debate, we will explore the leading contemporary mechanisms hypothesized to contribute to CE during liver disease.
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Affiliation(s)
- Eric M Liotta
- Northwestern University-Feinberg School of Medicine, Department of Neurology, United States; Northwestern University-Feinberg School of Medicine, Department of Surgery, Division of Organ Transplantation, United States; Northwestern University Transplant Outcomes Research Collaboration, United States.
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Helms HCC, Kristensen M, Saaby L, Fricker G, Brodin B. Drug Delivery Strategies to Overcome the Blood-Brain Barrier (BBB). Handb Exp Pharmacol 2020; 273:151-183. [PMID: 33367937 DOI: 10.1007/164_2020_403] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The brain capillary endothelium serves both as an exchange site for gases and solutes between blood and brain and as a protective fence against neurotoxic compounds from the blood. While this "blood-brain barrier" (BBB) function protects the fragile environment in the brain, it also poses a tremendous challenge for the delivery of drug compounds to the brain parenchyma. Paracellular brain uptake of drug compounds is limited by the physical tightness of the endothelium, which is tightly sealed with junction complexes. Transcellular uptake of lipophilic drug compounds is limited by the activity of active efflux pumps in the luminal membrane. As a result, the majority of registered CNS drug compounds are small lipophilic compounds which are not efflux transporter substrates. Small molecule CNS drug development therefore focuses on identifying compounds with CNS target affinity and modifies these in order to optimize lipophilicity and decrease efflux pump interactions. Since efflux pump activity is limiting drug uptake, it has been investigated whether coadministration of drug compounds with efflux pump inhibitors could increase drug uptake. While the concept works to some extent, a lot of challenges have been encountered in terms of obtaining efficient inhibition while avoiding adverse effects.Some CNS drug compounds enter the brain via nutrient transport proteins, an example is the levodopa, a prodrug of Dopamine, which crosses the BBB via the large neutral amino acid transporter LAT1. While carrier-mediated transport of drug compounds may seem attractive, the development of drugs targeting transporters is very challenging, since the compounds should have a good fit to the binding site, while still maintaining their CNS target affinity.Receptor-mediated transport of drug compounds, especially biotherapeutics, conjugated to a receptor-binding ligand has shown some promise, although the amounts transported are rather low. This also holds true for drug-conjugation to cell-penetrating peptides. Due to the low uptake of biotherapeutics, barrier-breaching approaches such as mannitol injections and focused ultrasound have been employed with some success to patient groups with no other treatment options.
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Affiliation(s)
| | - Mie Kristensen
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lasse Saaby
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Bioneer-Farma, Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Gert Fricker
- Institute of Pharmacy and Molecular Biotechnology, Ruprecht-Karls-University, Heidelberg, Germany
| | - Birger Brodin
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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Fortin D. Drug Delivery Technology to the CNS in the Treatment of Brain Tumors: The Sherbrooke Experience. Pharmaceutics 2019; 11:pharmaceutics11050248. [PMID: 31137918 PMCID: PMC6571772 DOI: 10.3390/pharmaceutics11050248] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 05/21/2019] [Accepted: 05/22/2019] [Indexed: 12/22/2022] Open
Abstract
Drug delivery to the central nervous system (CNS) remains a challenge in neuro-oncology. Despite decades of research in this field, no consensus has emerged as to the best approach to tackle this physiological limitation. Moreover, the relevance of doing so is still sometimes questioned in the community. In this paper, we present our experience with CNS delivery strategies that have been developed in the laboratory and have made their way to the clinic in a continuum of translational research. Using the intra-arterial (IA) route as an avenue to deliver chemotherapeutics in the treatment of brain tumors, complemented by an osmotic breach of the blood-brain barrier (BBB) in specific situations, we have developed over the years a comprehensive research effort on this specialized topic. Looking at pre-clinical work supporting the rationale for this approach, and presenting results discussing the safety of the strategy, as well as results obtained in the treatment of malignant gliomas and primary CNS lymphomas, this paper intends to comprehensively summarize our work in this field.
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Affiliation(s)
- David Fortin
- Division of Neurosurgery and Neuro-Oncology, Department of surgery, Faculty of Medicine and Health Science, University of Sherbrooke, Sherbrooke, Québec, J1H-5N4, Canada.
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Tosi U, Marnell CS, Chang R, Cho WC, Ting R, Maachani UB, Souweidane MM. Advances in Molecular Imaging of Locally Delivered Targeted Therapeutics for Central Nervous System Tumors. Int J Mol Sci 2017; 18:ijms18020351. [PMID: 28208698 PMCID: PMC5343886 DOI: 10.3390/ijms18020351] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 12/19/2016] [Accepted: 01/26/2017] [Indexed: 12/24/2022] Open
Abstract
Thanks to the recent advances in the development of chemotherapeutics, the morbidity and mortality of many cancers has decreased significantly. However, compared to oncology in general, the field of neuro-oncology has lagged behind. While new molecularly targeted chemotherapeutics have emerged, the impermeability of the blood–brain barrier (BBB) renders systemic delivery of these clinical agents suboptimal. To circumvent the BBB, novel routes of administration are being applied in the clinic, ranging from intra-arterial infusion and direct infusion into the target tissue (convection enhanced delivery (CED)) to the use of focused ultrasound to temporarily disrupt the BBB. However, the current system depends on a “wait-and-see” approach, whereby drug delivery is deemed successful only when a specific clinical outcome is observed. The shortcomings of this approach are evident, as a failed delivery that needs immediate refinement cannot be observed and corrected. In response to this problem, new theranostic agents, compounds with both imaging and therapeutic potential, are being developed, paving the way for improved and monitored delivery to central nervous system (CNS) malignancies. In this review, we focus on the advances and the challenges to improve early cancer detection, selection of targeted therapy, and evaluation of therapeutic efficacy, brought forth by the development of these new agents.
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Affiliation(s)
- Umberto Tosi
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA.
| | - Christopher S Marnell
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA.
| | - Raymond Chang
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA.
| | - William C Cho
- Department of Clinical Oncology, Queen Elizabeth Hospital, Kowloon, Hong Kong, China.
| | - Richard Ting
- Department of Radiology, Molecular Imaging Innovations Institute, Weill Cornell Medicine, New York, NY 10065, USA.
| | - Uday B Maachani
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA.
| | - Mark M Souweidane
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA.
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Mangraviti A, Gullotti D, Tyler B, Brem H. Nanobiotechnology-based delivery strategies: New frontiers in brain tumor targeted therapies. J Control Release 2016; 240:443-453. [DOI: 10.1016/j.jconrel.2016.03.031] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 02/05/2016] [Accepted: 03/18/2016] [Indexed: 02/06/2023]
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Azad TD, Pan J, Connolly ID, Remington A, Wilson CM, Grant GA. Therapeutic strategies to improve drug delivery across the blood-brain barrier. Neurosurg Focus 2015; 38:E9. [PMID: 25727231 DOI: 10.3171/2014.12.focus14758] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Resection of brain tumors is followed by chemotherapy and radiation to ablate remaining malignant cell populations. Targeting these populations stands to reduce tumor recurrence and offer the promise of more complete therapy. Thus, improving access to the tumor, while leaving normal brain tissue unscathed, is a critical pursuit. A central challenge in this endeavor lies in the limited delivery of therapeutics to the tumor itself. The blood-brain barrier (BBB) is responsible for much of this difficulty but also provides an essential separation from systemic circulation. Due to the BBB's physical and chemical constraints, many current therapies, from cytotoxic drugs to antibody-based proteins, cannot gain access to the tumor. This review describes the characteristics of the BBB and associated changes wrought by the presence of a tumor. Current strategies for enhancing the delivery of therapies across the BBB to the tumor will be discussed, with a distinction made between strategies that seek to disrupt the BBB and those that aim to circumvent it.
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Affiliation(s)
- Tej D Azad
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, California
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Foley CP, Rubin DG, Santillan A, Sondhi D, Dyke JP, Crystal RG, Gobin YP, Ballon DJ. Intra-arterial delivery of AAV vectors to the mouse brain after mannitol mediated blood brain barrier disruption. J Control Release 2014; 196:71-78. [PMID: 25270115 DOI: 10.1016/j.jconrel.2014.09.018] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Revised: 09/13/2014] [Accepted: 09/20/2014] [Indexed: 11/17/2022]
Abstract
The delivery of therapeutics to neural tissue is greatly hindered by the blood brain barrier (BBB). Direct local delivery via diffusive release from degradable implants or direct intra-cerebral injection can bypass the BBB and obtain high concentrations of the therapeutic in the targeted tissue, however the total volume of tissue that can be treated using these techniques is limited. One treatment modality that can potentially access large volumes of neural tissue in a single treatment is intra-arterial (IA) injection after osmotic blood brain barrier disruption. In this technique, the therapeutic of interest is injected directly into the arteries that feed the target tissue after the blood brain barrier has been disrupted by exposure to a hyperosmolar mannitol solution, permitting the transluminal transport of the therapy. In this work we used contrast enhanced magnetic resonance imaging (MRI) studies of IA injections in mice to establish parameters that allow for extensive and reproducible BBB disruption. We found that the volume but not the flow rate of the mannitol injection has a significant effect on the degree of disruption. To determine whether the degree of disruption that we observed with this method was sufficient for delivery of nanoscale therapeutics, we performed IA injections of an adeno-associated viral vector containing the CLN2 gene (AAVrh.10CLN2), which is mutated in the lysosomal storage disorder Late Infantile Neuronal Ceroid Lipofuscinosis (LINCL). We demonstrated that IA injection of AAVrh.10CLN2 after BBB disruption can achieve widespread transgene production in the mouse brain after a single administration. Further, we showed that there exists a minimum threshold of BBB disruption necessary to permit the AAV.rh10 vector to pass into the brain parenchyma from the vascular system. These results suggest that IA administration may be used to obtain widespread delivery of nanoscale therapeutics throughout the murine brain after a single administration.
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Affiliation(s)
- Conor P Foley
- Department of Radiology, Weill Cornell Medical College, 516 E 72nd Street, New York, NY 10021, USA
| | - David G Rubin
- Department of Neurosurgery, Weill Cornell Medical College, 525 East 68 Street, New York, NY 10065, USA
| | - Alejandro Santillan
- Department of Neurosurgery, Weill Cornell Medical College, 525 East 68 Street, New York, NY 10065, USA
| | - Dolan Sondhi
- Department of Genetic Medicine, Weill Cornell Medical College, 1305 York Avenue, New York, NY 10021, USA
| | - Jonathan P Dyke
- Department of Radiology, Weill Cornell Medical College, 516 E 72nd Street, New York, NY 10021, USA
| | - Ronald G Crystal
- Department of Genetic Medicine, Weill Cornell Medical College, 1305 York Avenue, New York, NY 10021, USA
| | - Y Pierre Gobin
- Department of Neurosurgery, Weill Cornell Medical College, 525 East 68 Street, New York, NY 10065, USA
| | - Douglas J Ballon
- Department of Radiology, Weill Cornell Medical College, 516 E 72nd Street, New York, NY 10021, USA
- Department of Genetic Medicine, Weill Cornell Medical College, 1305 York Avenue, New York, NY 10021, USA
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A novel gadolinium-based trimetasphere metallofullerene for application as a magnetic resonance imaging contrast agent. Invest Radiol 2014; 48:745-54. [PMID: 23748228 DOI: 10.1097/rli.0b013e318294de5d] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Macromolecular contrast agents for magnetic resonance imaging (MRI) are useful blood-pool agents because of their long systemic half-life and have found applications in monitoring tumor vasculature and angiogenesis. Macromolecular contrast agents have been able to overcome some of the disadvantages of the conventional small-molecule contrast agent Magnevist (gadolinium-diethylenetriaminepentaacetic acid), such as rapid extravasation and quick renal clearance, which limits the viable MRI time. There is an urgent need for new MRI contrast agents that increase the sensitivity of detection with a higher relaxivity, longer blood half-life, and reduced toxicity from free Gd3+ ions. Here, we report on the characterization of a novel water-soluble, derivatized, gadolinium-enclosed metallofullerene nanoparticle (Hydrochalarone-1) in development as an MRI contrast agent. MATERIALS AND METHODS The physicochemical properties of Hydrochalarone-1 were characterized by dynamic light scattering (hydrodynamic diameter), atomic force microscopy (particle height), ζ potential analysis (surface charge), and inductively coupled plasma-mass spectrometry (gadolinium concentration). The blood compatibility of Hydrochalarone-1 was also assessed in vitro through analysis of hemolysis, platelet aggregation, and complement activation of human blood. In vitro relaxivities, in vivo pharmacokinetics, and a pilot in vivo acute toxicity study were also performed. RESULTS An extensive in vitro and in vivo characterization of Hydrochalarone-1 is described here. The hydrodynamic size of Hydrochalarone-1 was 5 to 7 nm depending on the dispersing media, and it was negatively charged at physiological pH. Hydrochalarone-1 showed compatibility with blood cells in vitro, and no significant hemolysis, platelet aggregation, or complement activation was observed in vitro. In addition, Hydrochalarone-1 had significantly higher r1 and r2 in vitro relaxivities in human plasma in comparison with Magnevist and was not toxic at the doses administered in an in vivo pilot acute-dose toxicity study in mice.In vivo MRI pharmacokinetic analysis after a single intravenous injection of Hydrochalarone-1 (0.2 mmol Gd/kg) showed that the volume of distribution at steady state was approximately 100 mL/kg, suggesting prolonged systemic circulation. Hydrochalarone-1 also had a long blood half-life (88 minutes) and increased relaxivity, suggesting application as a promising blood-pool MRI contrast agent. CONCLUSIONS The evidence suggests that Hydrochalarone-1, with its long systemic half-life, may have significant utility as a blood-pool MRI contrast agent.
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Blanchette M, Tremblay L, Lepage M, Fortin D. Impact of drug size on brain tumor and brain parenchyma delivery after a blood-brain barrier disruption. J Cereb Blood Flow Metab 2014; 34:820-6. [PMID: 24517973 PMCID: PMC4013755 DOI: 10.1038/jcbfm.2014.14] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 01/02/2014] [Indexed: 11/09/2022]
Abstract
Drug delivery to the brain is influenced by the blood-brain barrier (BBB) and blood-tumor barrier (BTB) to an extent that is still debated in neuro-oncology. In this paper, we studied the delivery across the BTB and the BBB of compounds with different molecular sizes in normal and glioma-bearing rats. Studies were performed at baseline as well as after an osmotic BBB disruption (BBBD) using dynamic contrast-enhanced magnetic resonance imaging and two T₁ contrast agents (CAs), Magnevist (743 Da) and Gadomer (17,000 Da). More specifically, we determined the time window for the BBB permeability, the distribution and we calculated the brain exposure to the CAs. A different pattern of accumulation and distribution at baseline as well as after a BBBD procedure was observed for both agents, which is consistent with their different molecular size and weight. Baseline tumor exposure was threefold higher for Magnevist compared with Gadomer, whereas postBBBD tumor exposure was twofold higher for Magnevist. Our study clearly showed that the time window and the extent of delivery across the intact, as well as permeabilized BTB and BBB are influenced by drug size.
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Affiliation(s)
- Marie Blanchette
- Département de médecine nucléaire et radiobiologie, Centre d'imagerie moléculaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Luc Tremblay
- Département de médecine nucléaire et radiobiologie, Centre d'imagerie moléculaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Martin Lepage
- Département de médecine nucléaire et radiobiologie, Centre d'imagerie moléculaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - David Fortin
- Département de chirurgie, service de neurochirurgie et de neuro-oncologie, Université de Sherbrooke, Sherbrooke, Quebec, Canada
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Jiang S, Xia R, Jiang Y, Wang L, Gao F. Vascular endothelial growth factors enhance the permeability of the mouse blood-brain barrier. PLoS One 2014; 9:e86407. [PMID: 24551038 PMCID: PMC3925082 DOI: 10.1371/journal.pone.0086407] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 12/11/2013] [Indexed: 02/05/2023] Open
Abstract
The blood-brain barrier (BBB) impedes entry of many drugs into the brain, limiting clinical efficacy. A safe and efficient method for reversibly increasing BBB permeability would greatly facilitate central nervous system (CNS) drug delivery and expand the range of possible therapeutics to include water soluble compounds, proteins, nucleotides, and other large molecules. We examined the effect of vascular endothelial growth factor (VEGF) on BBB permeability in Kunming (KM) mice. Human VEGF165 was administered to treatment groups at two concentrations (1.6 or 3.0 µg/mouse), while controls received equal-volume saline. Changes in BBB permeability were measured by parenchymal accumulation of the contrast agent Gd-DTPA as assessed by 7 T magnetic resonance imaging (MRI). Mice were then injected with Evans blue, sacrificed 0.5 h later, and perfused transcardially. Brains were removed, fixed, and sectioned for histological study. Both VEGF groups exhibited a significantly greater signal intensity from the cerebral cortex and basal ganglia than controls (P<0.001). Evans blue fluorescence intensity was higher in the parenchyma and lower in the cerebrovasculature of VEGF-treated animals compared to controls. No significant brain edema was observed by diffusion weighted MRI (DWI) or histological staining. Exogenous application of VEGF can increase the permeability of the BBB without causing brain edema. Pretreatment with VEGF may be a feasible method to facilitate drug delivery into the CNS.
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Affiliation(s)
- Shize Jiang
- Molecular Imaging Laboratory, Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China, People’s Republic of
| | - Rui Xia
- Molecular Imaging Laboratory, Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China, People’s Republic of
| | - Yong Jiang
- Department of Pathology, West China Hospital, Sichuan University, Chengdu, Sichuan, China, People’s Republic of
| | - Lei Wang
- Molecular Imaging Laboratory, Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China, People’s Republic of
| | - Fabao Gao
- Molecular Imaging Laboratory, Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China, People’s Republic of
- * E-mail:
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Abstract
Cerebral palsy is a chronic childhood disorder that can have diverse etiologies. Injury to the developing brain that occurs either in utero or soon after birth can result in the motor, sensory, and cognitive deficits seen in cerebral palsy. Although the etiologies for cerebral palsy are variable, neuroinflammation plays a key role in the pathophysiology of the brain injury irrespective of the etiology. Currently, there is no effective cure for cerebral palsy. Nanomedicine offers a new frontier in the development of therapies for prevention and treatment of brain injury resulting in cerebral palsy. Nanomaterials such as dendrimers provide opportunities for the targeted delivery of multiple drugs that can mitigate several pathways involved in injury and can be delivered specifically to the cells that are responsible for neuroinflammation and injury. These materials also offer the opportunity to deliver agents that would promote repair and regeneration in the brain, resulting not only in attenuation of injury, but also enabling normal growth. In this review, the current advances in nanotechnology for treatment of brain injury are discussed with specific relevance to cerebral palsy. Future directions that would facilitate clinical translation in neonates and children are also addressed.
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Affiliation(s)
- Bindu Balakrishnan
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University; Baltimore, MD, USA
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16
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Charest G, Sanche L, Fortin D, Mathieu D, Paquette B. Optimization of the route of platinum drugs administration to optimize the concomitant treatment with radiotherapy for glioblastoma implanted in the Fischer rat brain. J Neurooncol 2013; 115:365-73. [PMID: 24026531 DOI: 10.1007/s11060-013-1238-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Accepted: 09/06/2013] [Indexed: 10/26/2022]
Abstract
Treatment of glioblastoma with platinum compounds modestly improves progression-free survival and may cause toxic effects which prevent use at higher dose that would otherwise improve the antineoplastic effect. To reduce toxicity, we propose to encapsulate the platinum drug in a liposome. We have also tested three methods of drug administration (intra-venous, intra-arterial and intra-arterial combined with blood brain barrier disruption) to determine which one optimizes the tumor cell uptake, limits the toxicity and delivers the best concomitance effect with radiotherapy. Cisplatin, oxaliplatin, their respective liposomal formulations, Lipoplatin™ and Lipoxal™, and carboplatin were assessed in F98 glioma, orthotopically implanted in Fischer rats. We found that the modest accumulation of drugs in tumor cells after intra-venous injection was significantly improved when the intra-arterial route was used and further increased after the transient opening of the blood brain barrier with mannitol. The liposomal formulations have largely reduced the toxicity and have allowed a better exploitation of the anti-cancer activity of platinum agent. Although the liposomes Lipoplatin™ and Lipoxal™ have shown a similar ability to that of carboplatin, to accumulate in brain tumors, the highest additive effect with radiotherapy was obtained with carboplatin. We conclude that the intra-arterial infusion of carboplatin or Lipoxal™ in concomitance with radiation therapy leads to the best tumor control as measured by an increase of mean survival time in Fischer rats implanted with the F98 glioma with a benefit in survival time of 13.4 and 6.5 days respectively compared to intra-venous.
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Affiliation(s)
- Gabriel Charest
- Center for Research in Radiotherapy, Department of Nuclear Medicine and Radiobiology, Faculty of Medicine and Heath Science, Université de Sherbrooke, Sherbrooke, QC, J1H 5N4, Canada,
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17
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Chacko AM, Li C, Pryma DA, Brem S, Coukos G, Muzykantov V. Targeted delivery of antibody-based therapeutic and imaging agents to CNS tumors: crossing the blood-brain barrier divide. Expert Opin Drug Deliv 2013; 10:907-26. [PMID: 23751126 PMCID: PMC4089357 DOI: 10.1517/17425247.2013.808184] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
INTRODUCTION Brain tumors are inherently difficult to treat in large part due to the cellular blood-brain barriers (BBBs) that limit the delivery of therapeutics to the tumor tissue from the systemic circulation. Virtually no large molecules, including antibody-based proteins, can penetrate the BBB. With antibodies fast becoming attractive ligands for highly specific molecular targeting to tumor antigens, a variety of methods are being investigated to enhance the access of these agents to intracranial tumors for imaging or therapeutic applications. AREAS COVERED This review describes the characteristics of the BBB and the vasculature in brain tumors, described as the blood-brain tumor barrier (BBTB). Antibodies targeted to molecular markers of central nervous system (CNS) tumors will be highlighted, and current strategies for enhancing the delivery of antibodies across these cellular barriers into the brain parenchyma to the tumor will be discussed. Noninvasive imaging approaches to assess BBB/BBTB permeability and/or antibody targeting will be presented as a means of guiding the optimal delivery of targeted agents to brain tumors. EXPERT OPINION Preclinical and clinical studies highlight the potential of several approaches in increasing brain tumor delivery across the BBB divide. However, each carries its own risks and challenges. There is tremendous potential in using neuroimaging strategies to assist in understanding and defining the challenges to translating and optimizing molecularly targeted antibody delivery to CNS tumors to improve clinical outcomes.
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Affiliation(s)
- Ann-Marie Chacko
- University of Pennsylvania, Perelman School of Medicine, Nuclear Medicine & Clinical Molecular Imaging, Department of Radiology, 231 S. 34 Street, Room 288, Philadelphia, PA 19104, USA
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18
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Blanchette M, Michaud K, Fortin D. A new method of quantitatively assessing the opening of the blood–brain barrier in murine animal models. J Neurosci Methods 2012; 207:125-9. [DOI: 10.1016/j.jneumeth.2012.03.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2007] [Revised: 03/21/2012] [Accepted: 03/22/2012] [Indexed: 11/30/2022]
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Vlachos F, Tung YS, Konofagou E. Permeability dependence study of the focused ultrasound-induced blood-brain barrier opening at distinct pressures and microbubble diameters using DCE-MRI. Magn Reson Med 2011; 66:821-30. [PMID: 21465543 DOI: 10.1002/mrm.22848] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Revised: 12/21/2010] [Accepted: 01/03/2011] [Indexed: 12/22/2022]
Abstract
Blood-brain barrier opening using focused ultrasound and microbubbles has been experimentally established as a noninvasive and localized brain drug delivery technique. In this study, the permeability of the opening is assessed in the murine hippocampus after the application of focused ultrasound at three different acoustic pressures and microbubble sizes. Using dynamic contrast-enhanced MRI, the transfer rates were estimated, yielding permeability maps and quantitative K(trans) values for a predefined region of interest. The volume of blood-brain barrier opening according to the K(trans) maps was proportional to both the pressure and the microbubble diameter. A K(trans) plateau of ∼0.05 min(-1) was reached at higher pressures (0.45 and 0.60 MPa) for the larger sized bubbles (4-5 and 6-8 μm), which was on the same order as the K(trans) of the epicranial muscle (no barrier). Smaller bubbles (1-2 μm) yielded significantly lower permeability values. A small percentage (7.5%) of mice showed signs of damage under histological examination, but no correlation with permeability was established. The assessment of the blood-brain barrier permeability properties and their dependence on both the pressure and the microbubble diameter suggests that K(trans) maps may constitute an in vivo tool for the quantification of the efficacy of the focused ultrasound-induced blood-brain barrier opening.
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Affiliation(s)
- Fotios Vlachos
- Department of Biomedical Engineering, Columbia University, New York 10027, USA
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Abstract
Standard chemotherapy administered systemically has a limited efficacy in the treatment of brain tumors. One of the major obstacles in the treatment of brain neoplasias is the impediment to delivery across the intact blood-brain barrier (BBB). Many innovative approaches have been developed to circumvent this obstacle. One such strategy is BBB disruption (BBBD), which successfully increases the delivery of antineoplastic agents to the central nervous system (CNS). This chapter describes the application of the BBBD technique in rats. Different methods to evaluate and measure BBB permeability following hyperosmolar mannitol infusion including Evans blue staining, albumin immunohistochemistry, and dynamic magnetic resonance imaging are also described.
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Stam R. Electromagnetic fields and the blood–brain barrier. ACTA ACUST UNITED AC 2010; 65:80-97. [DOI: 10.1016/j.brainresrev.2010.06.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Revised: 06/09/2010] [Accepted: 06/09/2010] [Indexed: 10/19/2022]
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Bellavance MA, Poirier MB, Fortin D. Uptake and intracellular release kinetics of liposome formulations in glioma cells. Int J Pharm 2010; 395:251-9. [DOI: 10.1016/j.ijpharm.2010.05.017] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2010] [Revised: 05/07/2010] [Accepted: 05/12/2010] [Indexed: 01/07/2023]
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23
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Côté J, Savard M, Bovenzi V, Dubuc C, Tremblay L, Tsanaclis AM, Fortin D, Lepage M, Gobeil F. Selective tumor blood-brain barrier opening with the kinin B2 receptor agonist [Phe(8)psi(CH(2)NH)Arg(9)]-BK in a F98 glioma rat model: an MRI study. Neuropeptides 2010; 44:177-85. [PMID: 20080302 DOI: 10.1016/j.npep.2009.12.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Revised: 12/10/2009] [Accepted: 12/14/2009] [Indexed: 11/17/2022]
Abstract
Treatment of malignant glioma with chemotherapy is limited mostly because of delivery impediment related to the blood-brain barrier (BBB). One approach for transporting drugs across the BBB involves the activation of bradykinin-B2 receptors (BK-B2R). Our objective was to pharmacologically characterize the BBB permeability induced by the synthetic biostable BK-B2R analogue [Phe(8)psi(CH(2)NH)Arg(9)]-BK (R523) in F98 glioma-implanted Fischer rats. On day 10 post-inoculation, we detected the presence of B2R in the tumor cells and the peritumoral microvasculature (RT-PCR and immunohistochemistry). We assessed BBB permeability before and after the intracarotid (i.c.) infusion of R523 (0.1ml/min for 5min; 2.5, 10, and 50nmol/kg/min) using non-invasive dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with the different sized-contrast agents Gd-DTPA (0.5kDa) and Gadomer (17kDa) (0.25mmol/kg via the caudal vein). T(1)-weighted images were analyzed for the presence or absence of contrast enhancement within and surrounding the tumor area and mathematically processed to yield a contrast agent distribution volume (CADV), which was used as an indicator of vascular permeability. Our results showed that the agonist R523 increased, in a dose-dependent manner, the CADV indexes of Gd-DTPA and Gadomer, with a maximum 2-fold increase in brain uptake of both CA. The increase in CADV induced by R523 (10nmol/kg/min) was prevented by the B2R antagonist HOE140 (20nmol/kg/min, i.c.) and the nitric oxide synthase inhibitor L-NA (5mg/kg, i.v.) but not by the B1R antagonist R892 (20nmol/kg/min, i.c.) or the cyclooxygenase inhibitor Meclofenamate (5mg/kg, i.v.). The BBB permeabilizing effect of R523 (10nmol/kg/min) lasted for <1h and was accompanied by a dose-related fall in arterial blood pressure. We concluded that R523 allows the extravasation of hydrophilic macromolecular agents (17kDa) into tumor tissues by inducing selective tumor BBB permeability via B2R- and NO-dependent mechanisms.
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Affiliation(s)
- Jérôme Côté
- Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke, Sherbrooke, QC, Canada J1H 5N4
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