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Mu C, Dave N, Hu J, Desai P, Pauletti G, Bai S, Hao J. Solubilization of flurbiprofen into aptamer-modified PEG-PLA micelles for targeted delivery to brain-derived endothelial cells in vitro. J Microencapsul 2013; 30:701-8. [PMID: 23517066 DOI: 10.3109/02652048.2013.778907] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Novel aptamer-functionalized polyethylene glycol-polylactic acid (PEG-PLA) (APP) micelles were developed with the objective to target the transferrin receptor on brain endothelial cells. Flurbiprofen, a potential drug for therapeutic management of Alzheimer's disease (AD), was loaded into the APP micelles using the co-solvent evaporation method. Results indicated that 9.03% (w/w) of flurbiprofen was entrapped in APP with good retention capacity in vitro. Targeting potential of APPs was investigated using the transferring receptor-expressing murine brain endothelial bEND5 cell line. APPs significantly enhanced surface association of micelles to bEND5 cells as quantified by fluorescence spectroscopy. Most importantly, APPs significantly enhanced intracellular flurbiprofen delivery when compared to unmodified micelles. These results suggest that APP micelles may offer an effective strategy to deliver therapeutically effective flurbiprofen concentrations into the brain for AD patients.
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Affiliation(s)
- Chaofeng Mu
- Division of Pharmaceutical Sciences, James L. Winkle College of Pharmacy, University of Cincinnati , Cincinnati, OH , USA and
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In silico biological activity of steroids from the marine sponge Axinella carteri. Med Chem Res 2013. [DOI: 10.1007/s00044-012-0119-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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53
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Abstract
INTRODUCTION Development of drug delivery systems for brain delivery is one of the most challenging research topics in pharmaceutical areas, mainly due to the presence of the blood-brain barrier (BBB), which separates the blood from the cerebral parenchyma thus limiting the brain uptake of the majority of therapeutic agents. Among the several carriers, which have been studied to overcome this problem, liposomes have gained increasing attention as promising strategies for brain-targeted drug delivery. The most advantageous features of liposomes are their ability to incorporate and deliver large amounts of drug and the possibility to decorate their surface with different ligands. AREAS COVERED The purpose of this review is to explore the different approaches studied to transport and deliver therapeutics and imaging agents to the brain by using liposomes. In the first part of the review, particular attention is paid to describe the anatomy of the BBB and different physiological transport mechanisms available for drug permeation. In the second part, the different strategies for the delivery of a drug to the brain using liposomes are reviewed for each transport mechanism. EXPERT OPINION Over the last decade, there have been significant developments concerning liposomal brain delivery systems conjugated with selected ligands with high specificity and low immunogenicity. An universally useful liposomal formulation for brain targeting does not exist but liposome design must be modulated by the appropriate choice of the specific homing device and transport mechanism.
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Affiliation(s)
- Francesco Lai
- University of Cagliari, Dipartimento di Scienze della Vita e dell'Ambiente, Via Ospedale 72, 09124 Cagliari, Italy
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Hardenacke K, Kuhn J, Lenartz D, Maarouf M, Mai JK, Bartsch C, Freund HJ, Sturm V. Stimulate or degenerate: deep brain stimulation of the nucleus basalis Meynert in Alzheimer dementia. World Neurosurg 2012; 80:S27.e35-43. [PMID: 23246738 DOI: 10.1016/j.wneu.2012.12.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Revised: 11/16/2012] [Accepted: 12/07/2012] [Indexed: 12/14/2022]
Abstract
OBJECTIVE Deep brain stimulation (DBS) is a therapeutically effective neurosurgical method originally applied in movement disorders. Over time, the application of DBS has increasingly been considered as a therapeutic option for several neuropsychiatric disorders, including Gilles de la Tourette syndrome, obsessive compulsive disorder, major depression and addiction. Latest research suggests beneficial effects of DBS in Alzheimer dementia (AD). Because of the high prevalence and the considerable burden of the disease, we endeavored to discuss and reveal the challenges of DBS in AD. METHODS Recent literature on the pathophysiology of AD, including translational data and human studies, has been studied to generate a fundamental hypothesis regarding the effects of electrical stimulation on cognition and to facilitate our ongoing pilot study regarding DBS of the nucleus basalis Meynert (NBM) in patients with AD. RESULTS It is hypothesized that DBS in the nucleus basalis Meynert could probably improve or at least stabilize memory and cognitive functioning in patients with AD by facilitating neural oscillations and by enhancing the synthesis of nerve growth factors. CONCLUSIONS Considering the large number of patients suffering from AD, there is a great need for novel and effective treatment methods. Our research provides insights into the theoretical background of DBS in AD. Providing that our hypothesis will be validated by our ongoing pilot study, DBS could be an opportunity in the treatment of AD.
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Affiliation(s)
- Katja Hardenacke
- Department of Psychiatry and Psychotherapy, University of Cologne, Cologne, Germany
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Abstract
Fruits rich in phytochemicals have been shown to improve memory by protecting or enhancing neuronal functions mediated by neurotrophic factors, such as nerve growth factor (NGF), in the hippocampus. Mori Fructus (Morus alba L., Moraceae), also called mulberry, is used as a food, dietary supplement and an anti-ageing agent in traditional Oriental medicine. It is also known to contain abundant flavonoid compounds and to exhibit various pharmacological effects. The present study was performed to evaluate the memory-enhancing effect of Mori Fructus extract (ME) in mice, with a focus on NGF regulation. ME (20, 100 and 500 mg/kg per d for 7 d, per os) dose-dependently promoted NGF release in the mouse hippocampus, leading to phosphorylation of extracellular signal-regulated kinases and cyclic AMP response element-binding protein. ME significantly increased pre- and post-synapse formation, acetylcholine synthesisation, neuronal cell differentiation, neurite outgrowth and neuronal cell proliferation in the mouse hippocampus. Furthermore, ME significantly increased latency time in the passive avoidance task (P< 0·001) and recognition time of novel objects in the object recognition test (P< 0·05), indicating improvements in learning and memory. Taken together, these data suggest that ME exhibits a memory-enhancing effect via up-regulation of NGF.
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Obianyo O, Ye K. Novel small molecule activators of the Trk family of receptor tyrosine kinases. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2012; 1834:2213-8. [PMID: 22982231 DOI: 10.1016/j.bbapap.2012.08.021] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Accepted: 08/29/2012] [Indexed: 12/18/2022]
Abstract
The Tropomyosin-related kinase (Trk) receptors are a subset of the receptor tyrosine kinase family with an important functionality in the regulation of neurotrophic signaling in the peripheral and central nervous system. As the receptors are able to mediate neuronal survival by associating with their respective neurotrophin ligands, many studies have focused on the therapeutic potential of generating small-molecule mimetic compounds that elicit agonistic effects similar to those of the natural protein ligands. To this end, various structure-based studies have led to the generation of bivalent peptide-based agonists and antibodies that selectively initiate Trk receptor signaling; however, these compounds do not possess the ideal characteristics of a potential drug. Additionally, the reliance of structure-based data to generate the compound libraries, limits the potential identification of novel chemical structures with desirable activity. Therefore, subsequent investigations utilized a cell-based apoptotic screen to facilitate the analysis of large, diverse chemical libraries of small molecules and quickly identify compounds with Trk-dependent anti-apoptotic activity. Herein, we describe the Trk agonists that have been identified by this screening methodology and summarize their in vitro and in vivo neurotrophic activity as well as their efficacy in various neurological disease models, implicating their future utility as therapeutic compounds. This article is part of a Special Issue entitled: Emerging recognition and activation mechanisms of receptor tyrosine kinases.
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Affiliation(s)
- Obiamaka Obianyo
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
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Translating the therapeutic potential of neurotrophic factors to clinical 'proof of concept': a personal saga achieving a career-long quest. Neurobiol Dis 2012; 48:153-78. [PMID: 22525569 DOI: 10.1016/j.nbd.2012.04.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 02/29/2012] [Accepted: 04/06/2012] [Indexed: 01/19/2023] Open
Abstract
While the therapeutic potential of neurotrophic factors has been well-recognized for over two decades, attempts to translate that potential to the clinic have been disappointing, largely due to significant delivery obstacles. Similarly, gene therapy (or gene transfer) emerged as a potentially powerful, new therapeutic approach nearly two decades ago and despite its promise, also suffered serious setbacks when applied to the human clinic. As advances continue to be made in both fields, ironically, they may now be poised to complement each other to produce a translational breakthrough. The accumulated data argue that gene transfer provides the 'enabling technology' that can solve the age-old delivery problems that have plagued the translation of neurotrophic factors as treatments for chronic central nervous system diseases. A leading translational program applying gene transfer to deliver a neurotrophic factor to rejuvenate and protect degenerating human neurons is CERE-120 (AAV2-NRTN). To date, over two dozen nonclinical studies and three clinical trials have been completed. A fourth (pivotal) clinical trial has completed all dosing and is currently evaluating safety and efficacy. In total, eighty Parkinson's disease (PD) subjects have thus far been dosed with CERE-120 (some 7 years ago), representing over 250 cumulative patient-years of exposure, with no serious safety issues identified. In a completed sham-surgery, double-blinded controlled trial, though the primary endpoint (the Unified Parkinson's Disease Rating Scale (UDPRS) motor off score measured at 12 months) did not show benefit from CERE-120, several important motor and quality of life measurements did, including the same UPDRS-motor-off score, pre-specified to also be measured at a longer, 18-month post-dosing time point. Importantly, not a single measurement favored the sham control group. This study therefore, provided important, well-controlled evidence establishing 'clinical proof of concept' for gene transfer to the CNS and the first controlled evidence for clinical benefit of a neurotrophic factor in a human neurodegenerative disease. This paper reviews the development of CERE-120, starting historically with the long-standing interest in the therapeutic potential of neurotrophic factors and continuing with selective accounts of past efforts to translate their potential to the clinic, eventually leading to the application of gene transfer and its role as the 'enabling technology'. Because of growing interest in translational R&D, including its practice in industry, the paper is uniquely oriented from the author's personal, quasi-autobiographic perspective and career-long experiences conducting translational research and development, with a focus on various translational neurotrophic factor programs spanning 30+ years in Big Pharma and development-stage biotech companies. It is hoped that by sharing these perspectives, practical insight and information might be provided to others also interested in translational R&D as well as neurotrophic factors and gene therapy, offering readers the opportunity to benefit from some of our successes, while possibly avoiding some of our missteps.
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Okada H. Drug discovery by formulation design and innovative drug delivery systems (DDS). YAKUGAKU ZASSHI 2012; 131:1271-87. [PMID: 21881300 DOI: 10.1248/yakushi.131.1271] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This review describes studies on drug discovery using a rational formulation design and innovative, drug delivery systems (DDS) for biomaterials such as therapeutic peptides and nucleotides. The microcapsules of the LH-RH superagonist leuprorelin acetate prepared using the new in-water drying method and biodegradable polymers, such as PLGA and PLA, could achieve a long-term sustained release for 1-6 months thereby facilitating easily treatment of hormone-dependent diseases, prostate cancer, endometriosis, and precocious puberty. This DDS technology showed an improvement in patient QOL and highly promoted the clinical value of the agonist. Moreover, PLGA microcapsules of siRNAs against VEGF, cFLIP, Raf-1, and Int6 have also been developed to treat various cancers and arteriosclerosis obliterans. To develop therapeutic nucleotides, a particle design is created using functional peptides, such as cell penetrating peptides (CPP), nuclear localizing signals (NLS), tight junction reversible openers (AT1002), bombesin, and dynein light chain-associated sequences. siRNA use should lead to a paradigm shift in drug discovery against various diseases. Tat analog with NLS could enhance the potency of a vaginal DNA vaccine. The artificial Tat CPP of STR-CH(2)R(4)H(2)C synthesized in our laboratory could efficiently deliver siRNAs into many types of cells and enhance the therapeutic effects for treating sarcoma, atopic dermatitis, allergic rhinitis, and asthma by intratumor injection and inhalation of the nanoparticles. Tat and AT1002 analogs used to treat atopic dermatitis in mice increased cell membrane permeability to siRelA, a siRNA against a subclass of NF-κB, and exhibited striking therapeutic and preventive effects.
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Affiliation(s)
- Hiroaki Okada
- Tokyo University of Pharmacy & Life Sciences, Tokyo, Japan.
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Sarkar G, Curran GL, Mahlum E, Decklever T, Wengenack TM, Blahnik A, Hoesley B, Lowe VJ, Poduslo JF, Jenkins RB. A carrier for non-covalent delivery of functional beta-galactosidase and antibodies against amyloid plaques and IgM to the brain. PLoS One 2011; 6:e28881. [PMID: 22216132 PMCID: PMC3244419 DOI: 10.1371/journal.pone.0028881] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 11/16/2011] [Indexed: 11/18/2022] Open
Abstract
Background Therapeutic intervention of numerous brain-associated disorders currently remains unrealized due to serious limitations imposed by the blood-brain-barrier (BBB). The BBB generally allows transport of small molecules, typically <600 daltons with high octanol/water partition coefficients, but denies passage to most larger molecules. However, some receptors present on the BBB allow passage of cognate proteins to the brain. Utilizing such receptor-ligand systems, several investigators have developed methods for delivering proteins to the brain, a critical requirement of which involves covalent linking of the target protein to a carrier entity. Such covalent modifications involve extensive preparative and post-preparative chemistry that poses daunting limitations in the context of delivery to any organ. Here, we report creation of a 36-amino acid peptide transporter, which can transport a protein to the brain after routine intravenous injection of the transporter-protein mixture. No covalent linkage of the protein with the transporter is necessary. Approach A peptide transporter comprising sixteen lysine residues and 20 amino acids corresponding to the LDLR-binding domain of apolipoprotein E (ApoE) was synthesized. Transport of beta-galactosidase, IgG, IgM, and antibodies against amyloid plques to the brain upon iv injection of the protein-transporter mixture was evaluated through staining for enzyme activity or micro single photon emission tomography (micro-SPECT) or immunostaining. Effect of the transporter on the integrity of the BBB was also investigated. Principal Findings The transporter enabled delivery to the mouse brain of functional beta-galactosidase, human IgG and IgM, and two antibodies that labeled brain-associated amyloid beta plaques in a mouse model of Alzheimer's disease. Significance The results suggest the transporter is able to transport most or all proteins to the brain without the need for chemically linking the transporter to a protein. Thus, the approach offers an avenue for rapid clinical evaluation of numerous candidate drugs against neurological diseases including cancer. (299 words).
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Affiliation(s)
- Gobinda Sarkar
- Department of Experimental Pathology, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail: (GS); (RJ)
| | - Geoffry L. Curran
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Eric Mahlum
- Department of Experimental Pathology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Teresa Decklever
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Thomas M. Wengenack
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Anthony Blahnik
- Tissue and Cell Molecular Analysis Laboratory, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Bridget Hoesley
- Tissue and Cell Molecular Analysis Laboratory, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Val J. Lowe
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Joseph F. Poduslo
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Robert B. Jenkins
- Department of Experimental Pathology, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail: (GS); (RJ)
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Chu L, Wiley HS, Lauffenburger DA. Endocytic Relay as a Potential Means for Enhancing Ligand Transport through Cellular Tissue Matrices: Analysis and Possible Implications for Drug Delivery. ACTA ACUST UNITED AC 2011; 2:17-38. [PMID: 19877949 DOI: 10.1089/ten.1996.2.17] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The transport of peptide ligands, such as cytokines, through tissue is complicated by resistances due to cell multilayers and holdup in extracellular matrix. To determine whether it is possible for receptor-mediated endocytic trafficking to enhance ligand transport, we have developed a mathematical model of ligand flux through tissue containing cells possessing complementary receptors. Tissue is considered as two phases: the cell phase and the matrix phase; thus tissue is modeled as analogous to a packed bed reactor. This model allows calculation of steady-state flux of intact and degraded peptide through a one-dimensional cell/tissue matrix. Both environmental and molecular parameters were considered in this study. Results predict that three quantities should have a major influence on growth factor flux: the ratio of matrix diffusivity to intracellular "diffusivity" (D(m)/D(i)), the extracellular matrix proteolysis rate constant (k (prot)), and the fraction of internalized growth factor degraded (f(1)). For basal levels of intracellular degradation (0 < f(1) >/= 0.05) but no extracellular proteolysis, significant enhancement is possible only for D(m)/D(i) >/=1. f(1) increases, enhancement is only possible up to f(1)= 0.07 even for D(m)/D(i) < 1. For significant levels of extracellular proteolysis (k (prot) > 0), the requirements for D(m)/D(i) and f(1) to permit transport enhancement encompass a broader range with the exact values dependent on k (prot). These insights may be helpful for delivery of ligands generated from controlled-release devices or genetically modified autocrine cells, and may also provide better understanding of cytokine transport in embryonic development.
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Affiliation(s)
- L Chu
- Department of Chemical Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
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Kim KH, Kim MA, Moon E, Kim SY, Choi SZ, Son MW, Lee KR. Furostanol saponins from the rhizomes of Dioscorea japonica and their effects on NGF induction. Bioorg Med Chem Lett 2011; 21:2075-8. [PMID: 21353549 DOI: 10.1016/j.bmcl.2011.02.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Revised: 01/29/2011] [Accepted: 02/02/2011] [Indexed: 11/30/2022]
Abstract
The rhizome of Dioscorea japonica is a food and medicinal source known as 'San Yak' in Korea. Two new furostanol saponins, coreajaponins A (1) and B (2), together with 10 known compounds (3-12) were isolated from the rhizomes of D. japonica. Their structures were determined by spectroscopic methods, including 1D and 2D NMR techniques, HRMS, and chemical methods. Nerve growth factor (NGF), a crucial factor for neuronal survival and differentiation, can potentially improve neurodegenerative diseases and diabetic polyneuropathy. We evaluated the effects of isolates (1-12) on NGF induction in a C6 rat glioma cell line. Coreajaponin B (2) upregulated NGF content without significant cell toxicity, as did 6, 8, 9, and 11.
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Affiliation(s)
- Ki Hyun Kim
- Natural Products Laboratory, School of Pharmacy, Sungkyunkwan University, 300 Chonchon-dong, Jangan-ku, Suwon, Gyeonggi-do 440-746, Republic of Korea
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Magorivska IB, Bilyy RO, Havrylyuk AM, Chop'yak VV, Stoika RS, Kit YY. Anti-histone H1 IgGs from blood serum of systemic lupus erythematosus patients are capable of hydrolyzing histone H1 and myelin basic protein. J Mol Recognit 2010; 23:495-502. [PMID: 20583146 DOI: 10.1002/jmr.1033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Novel hydrolytic activity of the anti-histone H1 antibodies (Ab) toward histone H1 and myelin basic protein (MBP) was shown. Blood serum of ten patients with clinically diagnosed systemic lupus erythematosus (SLE), and nine healthy donors (control) were screened for the anti-histone H1 antibody- and anti-MBP antibody-mediated specific proteolytic activity. IgGs were isolated by chromatography on Protein G-Sepharose, and four of ten SLE patients appeared to possess IgGs that were capable of cleaving both histone H1 and MBP. Such activity was confirmed to be an intrinsic property of the IgG molecule, since it was preserved at gel filtration at alkaline and acidic pH. At the same time, proteolytic activity was absent in the sera-derived Ab of all healthy donors under control. Anti-histone IgGs were purified by the affinity chromatography on histone H1-Sepharose. Their cross-reactivity toward cationic proteins (histones, lysozyme, and MBP) and their capability of hydrolyzing histone H1 and MBP were detected. However, these IgGs were not cleaving core histones, lysozyme, or albumin. Capability of cleaving histone H1 and MBP was preserved after additional purification of anti-histone H1 IgGs by the HPLC gel filtration. The protease activity of anti-histone H1 IgG Ab was inhibited by serine protease inhibitors.
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Affiliation(s)
- Irina B Magorivska
- Institute of Cell Biology, National Academy of Sciences of Ukraine, Drahomanov Street 14/16, Lviv 79005, Ukraine
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63
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Hua Q, Qing X, Li P, Li W, Hou J, Hu J, Hong Q, Sun P, Zhu X. Brain microvascular endothelial cells mediate neuroprotective effects on ischemia/reperfusion neurons. JOURNAL OF ETHNOPHARMACOLOGY 2010; 129:306-313. [PMID: 20394814 DOI: 10.1016/j.jep.2010.03.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Revised: 03/19/2010] [Accepted: 03/21/2010] [Indexed: 05/29/2023]
Abstract
AIM OF THE STUDY The permeability of the blood-brain barrier (BBB) is a bottleneck for the development of new cerebropathy medications because the medication must be transmitted across the BBB to achieve its curative function. To explore a new approach to the treatment of brain disease, this study investigated the mediating effects of brain microvascular endothelial cells (MVECs) on injured neurons. MATERIALS AND METHODS MVECs and cortical neurons were cultured and damage by cerebral ischemia/reperfusion (I/R) was simulated. The conditioned media from four groups of MVECs - normal cells (N-CM), normal cells treated with Tong Luo Jiu Nao (TLJN) (NT-CM), simulated cerebral I/R cells (I/R-CM), and simulated cells treated with TLJN (I/RTCM) - were then collected. These conditioned media were added to neuronal cultures and the viability of the neurons was examined. RESULTS The results demonstrated that N-CM could alleviate I/R damage to neurons, and this capacity could be improved by TLJN treatment. However, I/R-CM could cause damage to normal and I/R neurons, while I/RT-CM could significantly alleviate the damage to I/R neurons. CONCLUSIONS We propose that MVECs secrete active substances that influence the survival of neurons, and so MVECs may mediate a neuroprotective effect on ischemia/reperfusion neurons.
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Affiliation(s)
- Qian Hua
- School of Preclinical Medicine, Beijing University of Chinese Medicine, Chaoyang District, Beijing, China
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64
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Moon E, Her Y, Lee JB, Park JH, Lee EH, Kim SH, Oh MS, Jang CG, Kim SY. The multi-herbal medicine Gongjin-dan enhances memory and learning tasks via NGF regulation. Neurosci Lett 2009; 466:114-9. [PMID: 19788912 DOI: 10.1016/j.neulet.2009.09.033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Revised: 09/14/2009] [Accepted: 09/15/2009] [Indexed: 11/18/2022]
Abstract
Nerve growth factor (NGF) decreases degeneration of cholinergic neurons, improves memory loss, and increases long-term potentiation and learning tasks. Therefore, NGF mimetics or NGF inducers may be important targets for the treatment of various neurodegenerative disorders. Traditionally, Gongjin-dan (GJD) has been used clinically for the treatment of central nervous system disorders. In this study, we examined the effects of GJD on NGF mimetic activity in PC12 cells and the induction of NGF secretion in primary astrocytes. Moreover, we also measured neuron survival by MAP-2 staining in an immobilization stress rat model and induction of long-term potentiation by the MEA system in rat hippocampus slices treated with dexamethasone. The behavioral syndrome by novel object test was also performed in mice. GJD increased neurite outgrowth in PC12 cells and NGF secretion in primary astrocytes. Also, it reduced neuronal cell death and increased long-term potentiation in the rat hippocampus. Moreover, the number of entries, the time spent and the distance moved in the center area of the test region by the mice was increased by oral administration of GJD in comparison with the distance moved over the total area. These data suggest that administration of GJD may improve memory and learning tasks via NGF regulation, and that it may have a potential for multiple function neuroprotection via NGF regulation.
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Affiliation(s)
- Eunjung Moon
- Graduate School of East-West Medical Science, Kyung Hee University Global Campus, #1 Seocheon-dong, Giheung-gu, Yongin, Gyeonggi-do 446-701, Republic of Korea
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Sigurdsson PÁL, Thorvaldsson T, Gizurarson S, Gunnarsson E. Olfactory Absorption of Insulin to the Brain. Drug Deliv 2008. [DOI: 10.3109/10717549709051892] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Pasechnik V, Price J. Section Review: Central & Peripheral Nervous Systems: Macromolecular drug delivery to the CNS with protein carriers. Expert Opin Investig Drugs 2008. [DOI: 10.1517/13543784.5.10.1255] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Dwibhashyam VSNM, Nagappa AN. Strategies for enhanced drug delivery to the central nervous system. Indian J Pharm Sci 2008; 70:145-53. [PMID: 20046703 PMCID: PMC2792490 DOI: 10.4103/0250-474x.41446] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2007] [Revised: 02/17/2008] [Accepted: 02/23/2008] [Indexed: 11/29/2022] Open
Abstract
Treating central nervous system diseases is very challenging because of the presence of a variety of formidable obstacles that impede drug delivery. Physiological barriers like the blood-brain barrier and blood-cerebrospinal fluid barrier as well as various efflux transporter proteins make the entry of drugs into the central nervous system very difficult. The present review provides a brief account of the blood brain barrier, the P-glycoprotein efflux and various strategies for enhancing drug delivery to the central nervous system.
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Affiliation(s)
- V. S. N. M. Dwibhashyam
- Pharmacy Practice Department, 4th Floor, Shirdi Sai Baba Cancer Hospital, Manipal-576 104, India
| | - A. N. Nagappa
- TherDose Pharma (P) Ltd., Plot No: 30-32, Survey No. 400, Prasanth Nagar, IE, Hyderabad-500 072, India
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Sathuluri RR, Yamamura S, Tamiya E. Microsystems technology and biosensing. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2008; 109:285-350. [PMID: 17999038 DOI: 10.1007/10_2007_078] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
This review addresses the recent developments in miniaturized microsystems or lab-on-a-chip devices for biosensing of different biomolecules: DNA, proteins, small molecules, and cells, especially at the single-molecule and single-cell level. In order to sense these biomolecules with sensitivity we have fabricated chip devices with respect to the biomolecule to be analyzed. The details of the fabrication are also dealt with in this review. We mainly developed microarray and microfluidic chip devices for DNA, protein, and cell analyses. In addition, we have introduced the porous anodic alumina layer chip with nanometer scale and gold nanoparticles for label-free sensing of DNA and protein interactions. We also describe the use of microarray and microfluidic chip devices for cell-based assays and single-cell analysis in drug discovery research.
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Affiliation(s)
- Ramachandra Rao Sathuluri
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi City, Ishikawa, 923-1292, Japan
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69
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Di Fausto V, Fiore M, Tirassa P, Lambiase A, Aloe L. Eye drop NGF administration promotes the recovery of chemically injured cholinergic neurons of adult mouse forebrain. Eur J Neurosci 2007; 26:2473-80. [PMID: 17970722 DOI: 10.1111/j.1460-9568.2007.05883.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We have recently shown that conjunctivally applied nerve growth factor (NGF) in rats can reach the retina, the optic nerve and the CNS. In the present study, we investigated whether NGF application as collyrium can promote the recovery of chemically injured basal forebrain cholinergic neurons. NGF was administered on the eye of adult male mice previously treated i.c.v. with ibotenic acid to impair cholinergic pathways. Mice were tested in the passive avoidance test, and after 2 weeks of NGF administration were killed and the brains used for structural, biochemical and molecular analyses. The results showed that application of NGF on the eye surface protected choline acetyl transferase levels. These findings strengthen the hypothesis that application of NGF on the eye can represent an alternative delivery route to promote the recovery of brain cells during degeneration, including neurons involved in learning and memory activities.
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Affiliation(s)
- Veronica Di Fausto
- Institute of Neurobiology and Molecular Medicine, Department of Neurobiology, National Research Council (CNR) Rome, Italy
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70
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Tan SA, Aebischer P. The problems of delivering neuroactive molecules to the CNS. CIBA FOUNDATION SYMPOSIUM 2007; 196:211-36; discussion 236-9. [PMID: 8866136 DOI: 10.1002/9780470514863.ch14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
At present, the aetiologies of many neurological and neurodegenerative diseases are unknown. However, emergence of a better understanding of these diseases, at both cellular and molecular levels, opens up the possibility of replacement therapies. The presence of the blood-brain barrier complicates the delivery of molecules to the central nervous system. Numerous attempts have been made to bypass this barrier either by delivering the drugs directly into the brain or by transplanting cells to produce the missing molecules in situ. This review explores several methods for delivering bioactive molecules into the CNS, including the use of permeabilizers, osmotic pumps, slow polymer release systems and transplantation of cells with or without the use of the encapsulation technology.
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Affiliation(s)
- S A Tan
- Gene Therapy Center, Lausanne University Medical School, CHU Vaudois, Switzerland
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71
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Abstract
Nervous system growth factors potently stimulate cell function and prevent neuronal death. These broad effects on survival and function arise from direct downstream activation of antiapoptotic pathways, inhibition of proapoptotic pathways, and stimulation of functionally important cellular mechanisms including ERK/MAP kinase and CREB. Thus, as a class, growth factors offer the potential to treat neurodegenerative disorders for the first time by preventing neuronal degeneration rather than compensating for cell loss after it has occurred. Different growth factors affect distinct and specific populations of neurons: the first nervous system growth factor identified, nerve growth factor, potentially stimulates the survival and function of basal forebrain cholinergic neurons, suggesting that nerve growth factor could be a means for reducing the cholinergic component of cell degeneration in Alzheimer disease. This review will discuss the transition of growth factors from preclinical studies to human clinical trials in Alzheimer disease. The implementation of clinical testing of growth factor therapy for neurologic disease has been constrained by the dual need to achieve adequate concentrations of these proteins in specific brain regions containing degenerating neurons, and preventing growth factor spread to nontargeted regions to avoid adverse effects. Gene therapy is one of a limited number of potential methods for achieving these requirements.
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Affiliation(s)
- Mark H Tuszynski
- Department of Neurosciences-0626, University of California-San Diego, La Jolla 92161, and Veterans Affairs Medical Center, San Diego, CA, USA.
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72
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Spencer BJ, Verma IM. Targeted delivery of proteins across the blood-brain barrier. Proc Natl Acad Sci U S A 2007; 104:7594-9. [PMID: 17463083 PMCID: PMC1857226 DOI: 10.1073/pnas.0702170104] [Citation(s) in RCA: 179] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Treatment of many neuronal degenerative disorders will require delivery of a therapeutic protein to neurons or glial cells across the whole CNS. The presence of the blood-brain barrier hampers the delivery of these proteins from the blood, thus necessitating a new method for delivery. Receptors on the blood-brain barrier bind ligands to facilitate their transport to the CNS; therefore, we hypothesized that by targeting these receptors, we may be able to deliver proteins to the CNS for therapy. Here, we report the use of the lentivirus vector system to deliver the lysosomal enzyme glucocerebrosidase and a secreted form of GFP to the neurons and astrocytes in the CNS. We fused the low-density lipoprotein receptor-binding domain of the apolipoprotein B to the targeted protein. This approach proved to be feasible for delivery of the protein and could possibly be used as a general method for delivery of therapeutic proteins to the CNS.
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Affiliation(s)
- Brian J. Spencer
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA 92037
| | - Inder M. Verma
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA 92037
- To whom correspondence should be addressed. E-mail:
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73
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Lambiase A, Pagani L, Di Fausto V, Sposato V, Coassin M, Bonini S, Aloe L. Nerve growth factor eye drop administrated on the ocular surface of rodents affects the nucleus basalis and septum: biochemical and structural evidence. Brain Res 2006; 1127:45-51. [PMID: 17113055 DOI: 10.1016/j.brainres.2006.09.102] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2006] [Revised: 09/27/2006] [Accepted: 09/29/2006] [Indexed: 11/15/2022]
Abstract
It has been shown that conjunctivally applied NGF in rats can reach the retina and optic nerve. Whether topical eye NGF application reaches the central nervous system is not known. In the present study, we have addressed this question. It was found that topical eye NGF application affects brain cells. Time-course studies revealed that repeated NGF application leads to high concentration of this neurotrophins after 6 h and normal levels after 24 h. Our results also showed that topical eye application of NGF causes an enhanced expression of NGF receptors and ChAT immunoreactivity in forebrain cholinergic neurons, suggesting that ocular NGF application could have a functional role on damaged brain cells. The present findings suggest that eye NGF application can represent an alternative route to prevent degeneration of NGF-receptive neurons involved in disorders such as Alzheimer and Parkinson.
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Affiliation(s)
- Alessandro Lambiase
- Department of Ophthalmology, University Campus Bio-Medico, G. B. Bietti Eye Foundation, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy
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75
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Williams BJ, Eriksdotter-Jonhagen M, Granholm AC. Nerve growth factor in treatment and pathogenesis of Alzheimer's disease. Prog Neurobiol 2006; 80:114-28. [PMID: 17084014 DOI: 10.1016/j.pneurobio.2006.09.001] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2006] [Accepted: 09/05/2006] [Indexed: 10/24/2022]
Abstract
The etiology of Alzheimer's disease (AD) is still unknown. In addition, this terrible neurodegenerative disease will increase exponentially over the next two decades due to longer lifespan and an aging "baby-boomer" generation. All treatments currently approved for AD have moderate efficacy in slowing the rate of cognitive decline in patients, and no efficacy in halting progression of the disease. Hence, there is an urgent need for new drug targets and delivery methods to slow or reverse the progression of AD. One molecule that has received much attention in its potential therapeutic role in AD is nerve growth factor (NGF). This review will demonstrate data from humans and animals which promote NGF as a potential therapeutic target by (1) outlining the hypothesis behind using NGF for the treatment of AD, (2) reviewing both the normal and AD altered signaling pathways and effects of NGF in the central nervous system (CNS), and (3) examining the results of NGF treatment obtained from animal models of AD and AD patients.
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Affiliation(s)
- Brice J Williams
- Department of Neurosciences and the Center on Aging, Medical University of South Carolina, 173 Ashley Ave BSB 403, Charleston, SC 29425, United States
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76
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de Vries NA, Beijnen JH, Boogerd W, van Tellingen O. Blood-brain barrier and chemotherapeutic treatment of brain tumors. Expert Rev Neurother 2006; 6:1199-209. [PMID: 16893347 DOI: 10.1586/14737175.6.8.1199] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The blood-brain barrier (BBB) is of pivotal importance to maintain homeostasis of the CNS, as it closely regulates the composition of the interstitial fluid in the brain. Unfortunately, malignancies that grow within the CNS may evade chemotherapeutic drugs using the same barrier, making this disease refractory to most chemotherapy regimens. This review will outline the impact of the BBB in brain cancer and discuss the efforts that have been made to enhance the drug exposure of brain tumors. Although this review will focus on the role of the BBB in primary brain cancer (malignant glioma), its impact on brain metastases will also be briefly discussed.
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Affiliation(s)
- Nienke A de Vries
- The Netherlands Cancer Institute, Department of Clinical Chemistry, Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.
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77
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Chen Q, Sowa DA, Cai J, Gabathuler R. Efficient One-Pot Synthesis of Doxorubicin Conjugates Through Its Amino Group to Melanotransferrin P97. SYNTHETIC COMMUN 2006. [DOI: 10.1081/scc-120021829] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Qingqi Chen
- a Biomarin Pharmaceutical Inc. , Novato, California, USA
| | - Damian A. Sowa
- a Biomarin Pharmaceutical Inc. , Novato, California, USA
| | - Jianlin Cai
- a Biomarin Pharmaceutical Inc. , Novato, California, USA
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78
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Zhu Y, Krieglstein J. β2-Adrenoceptor Agonist Clenbuterol Causes NGF Expression and Neuroprotection. CNS DRUG REVIEWS 2006. [DOI: 10.1111/j.1527-3458.1999.tb00110.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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79
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Hackel BJ, Huang D, Bubolz JC, Wang XX, Shusta EV. Production of Soluble and Active Transferrin Receptor-Targeting Single-Chain Antibody using Saccharomyces cerevisiae. Pharm Res 2006; 23:790-7. [PMID: 16550469 DOI: 10.1007/s11095-006-9778-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2005] [Accepted: 12/16/2005] [Indexed: 11/25/2022]
Abstract
PURPOSE This study describes the soluble production, purification, and functional testing of an anti-transferrin receptor single-chain antibody (OX26 scFv) using the yeast Saccharomyces cerevisiae. METHODS The yeast secretion apparatus was optimized by modulating expression temperature, the folding environment of the endoplasmic reticulum, and gene dosage. Secreted scFv was purified using immobilized metal affinity chromatography, and tested for binding and internalization into the RBE4 rat brain endothelial cell line. RESULTS Secretion of OX26 scFv was optimal when expression was induced at 20 degrees C. Co-overexpression of heavy chain binding protein and protein disulfide isomerase elevated scFv expression levels by 10.4 +/- 0.3-fold. Optimization of scFv gene dosage increased secretion by 7.1 +/- 0.2-fold, but the overall benefits of binding protein and protein disulfide isomerase overexpression were diminished. Purified OX26 scFv yields of 0.5 mg/L secreted protein were achieved, and the scFv was actively internalized into RBE4 cells with a pattern similar to that observed with intact OX26 monoclonal antibody. CONCLUSIONS The optimized S. cerevisiae expression system is amenable to production of soluble and active brain targeting OX26 scFv, and the yeast-produced scFv has potential for the targeting and delivery of small molecules, proteins, or drug carriers across the blood-brain barrier (BBB).
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Affiliation(s)
- Benjamin J Hackel
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, Wisconsin 53706, USA
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80
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Ponomarenko NA, Durova OM, Vorobiev II, Belogurov AA, Kurkova IN, Petrenko AG, Telegin GB, Suchkov SV, Kiselev SL, Lagarkova MA, Govorun VM, Serebryakova MV, Avalle B, Tornatore P, Karavanov A, Morse HC, Thomas D, Friboulet A, Gabibov AG. Autoantibodies to myelin basic protein catalyze site-specific degradation of their antigen. Proc Natl Acad Sci U S A 2006; 103:281-6. [PMID: 16387849 PMCID: PMC1324791 DOI: 10.1073/pnas.0509849103] [Citation(s) in RCA: 137] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Autoantibody-mediated tissue destruction is among the main features of organ-specific autoimmunity. This report describes "an antibody enzyme" (abzyme) contribution to the site-specific degradation of a neural antigen. We detected proteolytic activity toward myelin basic protein (MBP) in the fraction of antibodies purified from the sera of humans with multiple sclerosis (MS) and mice with induced experimental allergic encephalomyelitis. Chromatography and zymography data demonstrated that the proteolytic activity of this preparation was exclusively associated with the antibodies. No activity was found in the IgG fraction of healthy donors. The human and murine abzymes efficiently cleaved MBP but not other protein substrates tested. The sites of MBP cleavage determined by mass spectrometry were localized within immunodominant regions of MBP. The abzymes could also cleave recombinant substrates containing encephalytogenic MBP(85-101) peptide. An established MS therapeutic Copaxone appeared to be a specific abzyme inhibitor. Thus, the discovered epitope-specific antibody-mediated degradation of MBP suggests a mechanistic explanation of the slow development of neurodegeneration associated with MS.
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Affiliation(s)
- Natalia A Ponomarenko
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10, Miklukho-Maklaya Street, Moscow 117997, Russia
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81
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Nosheny RL, Mocchetti I, Bachis A. Brain-derived neurotrophic factor as a prototype neuroprotective factor against HIV-1-associated neuronal degeneration. Neurotox Res 2005; 8:187-98. [PMID: 16260395 DOI: 10.1007/bf03033829] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Patients with human immunodeficiency virus type 1 (HIV-1) infection develop a broad spectrum of motor impairments and cognitive deficits, which follow or parallel cellular loss and atrophy in their brains. The viral envelope glycoprotein 120 (gp120) has been suggested to be a causal agent of neuronal loss. Therefore, reducing gp120 neurotoxicity may prevent neuronal degeneration seen in these patients. Here, we describe in vitro and in vivo experimental evidence that gp120 toxicity can be reduced by brain-derived neurotrophic factor (BDNF), a naturally occurring peptide that has been shown to block neurotoxin and trauma-induced neuronal injury. Moreover, we review the survival promoting properties of BDNF and the issues concerning its delivery into the brain, in an attempt to explain the rationale for exploring BDNF as a prototype trophic factor for a therapy to reduce neuronal cell death in HIV-1 infected patients.
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Affiliation(s)
- R L Nosheny
- Interdisciplinary Program in Neuroscience, Georgetown University Medical Center, Washington, DC 20057, USA
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82
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Abstract
In recent years, there have been several important advancements in the development of neuropeptide therapeutics. Nevertheless, the targeting of peptide drugs to the CNS remains a formidable obstacle. Delivery of peptide drugs is limited by their poor bioavailability to the brain due to low metabolic stability, high clearance by the liver, and the presence of the blood brain barrier (BBB). Multiple strategies have been devised in an attempt to improve peptide drug delivery to the brain, with variable results. In this review, we discuss several of the strategies that have been used to improve both bioavailability and BBB transport, with an emphasis on antibody based vector delivery, useful for large peptides/small proteins, and glycosylation, useful for small peptides. Further development of these delivery methods may finally enable peptide drugs to be useful for the treatment of neurological disease states.
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Affiliation(s)
- Richard D Egleton
- Department of Medical Pharmacology, University of Arizona College of Medicine, Tucson, Arizona 85724, USA.
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83
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Gao WQ, Weil RJ, Dugich-Djordjevic M, Lu B. The therapeutic potentials of neurotrophic factors for diseases of the nervous system. Expert Opin Ther Pat 2005. [DOI: 10.1517/13543776.7.4.325] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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84
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Prokai L. Peptide delivery into the central nervous system: invasive, physiological and chemical approaches. Expert Opin Ther Pat 2005. [DOI: 10.1517/13543776.7.3.233] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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85
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Egleton RD, Davis TP. Development of neuropeptide drugs that cross the blood-brain barrier. Neurotherapeutics 2005. [DOI: 10.1007/bf03206641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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86
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Pan W, Kastin AJ. Why study transport of peptides and proteins at the neurovascular interface. ACTA ACUST UNITED AC 2004; 46:32-43. [PMID: 15297153 DOI: 10.1016/j.brainresrev.2004.04.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/26/2004] [Indexed: 01/17/2023]
Abstract
The blood-brain barrier (BBB) is an immense neurovascular interface. In neurodegenerative, ischemic, and traumatic disorders of the central nervous system (CNS), the BBB may hinder the delivery of many therapeutic peptides and proteins to the brain and spinal cord. Fortunately, the mistaken dogma that peptides and proteins do not cross the BBB has been corrected during the past two decades by the accumulating evidence that peptides and proteins in the periphery exert potent effects in the CNS. Not only can peptides and proteins serve as carriers for selective therapeutic agents, but they themselves may directly cross the BBB after delivery into the bloodstream. Their passage may be mediated by simple diffusion or specific transport, both of which can be affected by interactions in the blood compartment (outside the BBB) and within the endothelial cells (at the BBB level). Although the majority of current delivery strategies focuses on modification of the molecule to be delivered, understanding the mechanisms of transport will eventually facilitate regulation of the BBB directly. We review the different aspects of interactions and discuss recent advances in the cell biology of peptide/protein transport across the BBB. Better understanding of the nature and regulation of the transport systems at the BBB will provide a new direction to enhance the interactions of peripheral peptides and proteins with the CNS.
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Affiliation(s)
- Weihong Pan
- Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA 70808, USA.
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87
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Burdo JR, Antonetti DA, Wolpert EB, Connor JR. Mechanisms and regulation of transferrin and iron transport in a model blood-brain barrier system. Neuroscience 2004; 121:883-90. [PMID: 14580938 DOI: 10.1016/s0306-4522(03)00590-6] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
For peripheral iron to reach the brain, it must transverse the blood-brain barrier. In order for the brain to obtain iron, transferrin receptors are present in the vascular endothelial cell to facilitate movement of transferrin bound iron into the brain parenchyma. However, a number of significant voids exist in our knowledge about transport of iron into the brain. These gaps in our knowledge are significant not only because iron is an essential neurotrophic factor but also because the system for delivery of iron into the brain is being viewed as an opportunity to circumvent the blood-brain barrier for delivery of neurotoxins to tumors or trophic factors in neurodegenerative diseases. In this study, we have used fluorescein-transferrin-59Fe in a bovine retinal endothelial cell culture system to determine the mechanism of transferrin-iron transport and to test the hypothesis that the iron status of the endothelial cells would influence iron transport. Our results indicated that iron is transported across endothelial cells both bound to and not bound to transferrin. The ratio of non-transferrin-bound iron to transferrin-bound iron transported is dependent upon the iron status of the cells. Blocking acidification of endosomes led to a significant decrease in transport of non-transferrin-bound iron but not transferrin-bound iron. Blocking pinocytosis had no effect on either transferrin or iron transcytosis. These results indicate that there is both transferrin-mediated and non-transferrin-mediated transcytosis of iron and that the process is influenced by the iron status of the cells. These data have considerable implications for common neurodegenerative diseases that are associated with excess brain iron accumulation and the numerous neurological complications associated with brain iron deficiency.
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Affiliation(s)
- J R Burdo
- Department of Neuroscience, Pennsylvania State College of Medicine, Mail Code H109, 500 University Drive, Hershey, PA 17033, USA
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88
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Neuwelt EA. Mechanisms of Disease: The Blood-Brain Barrier. Neurosurgery 2004; 54:131-40; discussion 141-2. [PMID: 14683550 DOI: 10.1227/01.neu.0000097715.11966.8e] [Citation(s) in RCA: 240] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2003] [Accepted: 09/03/2003] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE The blood-brain barrier (BBB) is often perceived as a passive membrane. However, evidence has demonstrated that the BBB plays an active role in normal homeostasis and in certain disease processes. METHODS Approximately 300 peer-reviewed publications that discussed normal or abnormal BBB function were reviewed. RESULTS The role of the BBB and how it contributes to disorders of the central nervous system vary, depending on the specific disease process. CONCLUSION In health and disease and extending to old age, endothelial cells, neurons, and glia constitute a neurovascular unit that regulates the BBB. Advances toward penetrating the BBB must account for both normal and abnormal functions of the neurovascular unit.
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Affiliation(s)
- Edward A Neuwelt
- Department of Neurology, Oregon Health & Science University, Portland, Oregon 97201, USA.
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89
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Alberch J, Pérez-Navarro E, Canals JM. Neurotrophic factors in Huntington's disease. PROGRESS IN BRAIN RESEARCH 2004; 146:195-229. [PMID: 14699966 DOI: 10.1016/s0079-6123(03)46014-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Huntington's disease is a neurodegenerative disorder characterized by the selective loss of striatal neurons and, to a lesser extent, cortical neurons. The neurodegenerative process is caused by the mutation of huntingtin gene. Recent studies have established a link between mutant huntingtin, excitotoxicity and neurotrophic factors. Neurotrophic factors prevent cell death in degenerative processes but they can also enhance growth and function of neurons that are affected in Huntington's disease. The endogenous regulation of the expression of neurotrophic factors and their receptors in the striatum and its connections can be important to protect striatal cells and maintains basal ganglia connectivity. The administration of exogenous neurotrophic factors, in animal models of Huntington's disease, has been used to characterize the trophic requirements of striatal and cortical neurons. Neurotrophins, glial cell line-derived neurotrophic factor family members and ciliary neurotrophic factor have shown a potent neuroprotective effects on different neuronal populations of the striatum. Furthermore, they are also useful to maintain the integrity of the corticostriatal pathway. Thus, these neurotrophic factors may be suitable for the development of a neuroprotective therapy for neurodegenerative disorders of the basal ganglia.
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Affiliation(s)
- Jordi Alberch
- Department of Cell Biology and Pathology, Medical School, IDIBAPS, University of Barcelona, Casanova 143, E-08036 Barcelona, Spain.
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90
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Abstract
Nerve growth factor was the first identified protein with anti-apoptotic activity on neurons. This prototypic neurotrophic factor, together with the three structurally and functionally related growth factors brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT3) and neurotrophin-4/5 (NT4/5), forms the neurotrophin protein family. Target T cells for neurotrophins include many neurons affected by neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis and peripheral polyneuropathies. In addition, the neurotrophins act on neurons affected by other neurological and psychiatric pathologies including ischemia, epilepsy, depression and eating disorders. Work with cell cultures and animal models provided solid support for the hypothesis that neurotrophins prevent neuronal death. While no evidence exists that a lack of neurotrophins underlies the etiology of any neurodegenerative disease, these studies have spurred on hopes that neurotrophins might be useful symptomatic-therapeutic agents. However first clinical trials led to variable results and severe side effects were observed. For future therapeutic use of the neurotrophins it is therefore crucial to expand our knowledge about their physiological functions as well as their pharmacokinetic properties. A major challenge is to develop methods for their application in effective doses and in a precisely timed and localized fashion.
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Affiliation(s)
- Georg Dechant
- Neurobiochemistry, Max-Planck-Institute of Neurobiology, Am Klopferspitz 18a, 82152 Martinsried, Germany
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91
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Albeck D, Mesches MH, Juthberg S, Browning M, Bickford PC, Rose GM, Granholm AC. Exogenous NGF restores endogenous NGF distribution in the brain of the cognitively impaired aged rat. Brain Res 2003; 967:306-10. [PMID: 12650994 DOI: 10.1016/s0006-8993(03)02272-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Alzheimer's disease and normal aging may impair retrograde transport of nerve growth factor (NGF) from cortical areas to basal forebrain cholinergic neurons. We demonstrate a relationship between performance in a spatial reference memory task and NGF distribution in the aged rat brain. In addition, exogenous NGF restored endogenous NGF distribution in cognitively impaired aged rats. These data suggest that NGF administration restores utilization of endogenous growth factor in the brain of cognitively impaired aged rats.
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Affiliation(s)
- Dave Albeck
- Department of Psychology, University of Colorado at Denver, Campus Box 173, P.O. Box 173364, 80217-3364, USA.
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Vyas SP. CNS-delivery via conjugation to biological carriers: physiological-based approaches. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 2003; 61:189-219. [PMID: 14674613 DOI: 10.1007/978-3-0348-8049-7_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Affiliation(s)
- Suresh P Vyas
- Drug Delivery Research Laboratory, Department of Pharmaceutical Sciences, Dr. Harisingh Gour University, Sagar (M.P.) 470 003, India
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93
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Temsamani J, Scherrmann JM. Peptide vectors as drug carriers. PEPTIDE TRANSPORT AND DELIVERY INTO THE CENTRAL NERVOUS SYSTEM 2003; 61:221-38. [PMID: 14674614 DOI: 10.1007/978-3-0348-8049-7_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Jamal Temsamani
- Synt:em, Parc Scientifique Georges Besse, 30000 Nîmes, France
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94
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Banks WA, Terrell B, Farr SA, Robinson SM, Nonaka N, Morley JE. Passage of amyloid beta protein antibody across the blood-brain barrier in a mouse model of Alzheimer's disease. Peptides 2002; 23:2223-6. [PMID: 12535702 DOI: 10.1016/s0196-9781(02)00261-9] [Citation(s) in RCA: 141] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Vaccinations against amyloid beta protein (A beta P) reduce amyloid deposition and reverse learning and memory deficits in mouse models of Alzheimer's disease. This has raised the question of whether circulating antibodies, normally restricted by the blood-brain barrier (BBB), can enter the brain [Nat. Med. 7 (2001) 369-372]. Here, we show that antibody directed against A beta P does cross the BBB at a very low rate. Entry is by way of the extracellular pathways with about 0.11% of an intravenous (i.v.) dose entering the brain by 1h. Clearance of antibody from brain increasingly dominates over time, but antibody is still detectable in brain 72 h after i.v. injection. Uptake and clearance is not altered in mice overexpressing A beta P. This ability to enter and exit the brain even in the presence of increased brain ligand supports the use of antibody in the treatment of Alzheimer's and other diseases of the brain.
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Affiliation(s)
- William A Banks
- GRECC, Division of Geriatrics, Department of Internal Medicine, Veterans Affairs Medical Center-St. Louis and Saint Louis University School of Medicine, St. Louis, MO 63106, USA.
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95
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Thorne RG, Frey WH. Delivery of neurotrophic factors to the central nervous system: pharmacokinetic considerations. Clin Pharmacokinet 2002; 40:907-46. [PMID: 11735609 DOI: 10.2165/00003088-200140120-00003] [Citation(s) in RCA: 364] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Neurotrophic factors are proteins with considerable potential in the treatment of central nervous system (CNS) diseases and traumatic injuries. However, a significant challenge to their clinical use is the difficulty associated with delivering these proteins to the CNS. Neurotrophic factors are hydrophilic, typically basic, monomeric or dimeric proteins, mostly in the size range of 5 to 30 kDa. Neurotrophic factors potently support the development, growth and survival of neurons, eliciting biological effects at concentrations in the nanomolar to femtomolar range. They are not orally bioavailable and the blood-brain and blood-cerebrospinal fluid barriers severely limit their ability to enter into and act on sites in the CNS following parenteral systemic routes of administration. Most neurotrophic factors have short in vivo half-lives and poor pharmacokinetic profiles. Their access to the CNS is restricted by rapid enzymatic inactivation, multiple clearance processes, potential immunogenicity and sequestration by binding proteins and other components of the blood and peripheral tissues. The development of targeted drug delivery strategies for neurotrophic factors will probably determine their clinical effectiveness for CNS conditions. Achieving significant CNS target site concentrations while limiting systemic exposure and distribution to peripheral sites of action will lessen unwanted pleiotropic effects and toxicity. Local introduction of neurotrophic factors into the CNS intraparenchymally by direct injection/infusion or by implantation of delivery vectors such as polymer matrices or genetically modified cells yields the highest degree of targeting, but is limited by diffusion restrictions and invasiveness. Delivery of neurotrophic factors into the cerebrospinal fluid (CSF) following intracerebroventricular or intrathecal administration is less invasive and allows access to a much wider area of the CNS through CSF circulation pathways. However, diffusional and cellular barriers to penetration into surrounding CNS tissue and significant clearance of CSF into the venous and lymphatic circulation are also limiting. Unconventional delivery strategies such as intranasal administration may offer some degree of CNS targeting with minimal invasiveness. This review presents a summary of the neurotrophic factors and their indications for CNS disorders, their physicochemical characteristics and the different approaches that have been attempted or suggested for their delivery to the CNS. Future directions for further research such as the potential for CNS disease treatment utilising combinations of neurotrophic factors, displacement strategies, small molecule mimetics, chimaeric molecules and gene therapy are also discussed.
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Affiliation(s)
- R G Thorne
- Department of Pharmaceutics, University of Minnesota, Minneapolis, Minnesota, USA
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96
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Abstract
Genomics, the complete tabulation of all the genes in an organism, has made a major impact on the organisation of fully-integrated pharmaceutical companies. Drug discovery begins with bioinformatic elucidation of a human sequence encoding a potential drug target, followed by cloning and expression of the gene in a format for high throughput screening. Target validation is aided by reference to homologous genes in subhuman species as well as production of transgenic animals. In contrast, the impact of genetics on neuropsychopharmacology has been modest. It is interesting to compare the experience of genetics in the two major clinical disciplines dealing with disorders of the nervous system. Neurology has been at the forefront of human genetics with over 600 disorders mapped, of which causative mutations have been assigned to about 200 Mendelian disorders, each individually rare. Psychiatric genetics has been based on two log fewer diagnoses use of which has only yielded complex segregation patterns, a plethora of weak associations and no gene assignments. In neither case has genetics resulted in the development of a novel therapeutic agent. However, by refinements in diagnosis and genetic technology the promise for the future is great, not only for drug discovery, but also for subsequent preclinical and clinical development.
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Affiliation(s)
- O Hurko
- GlaxoSmithKline Neurology Center for Excellence in Drug Discovery New Frontiers Science Park North, H17 2-233 Harlow, Essex CM19 5AW, UK.
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97
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Rapoport SI. Advances in osmotic opening of the blood-brain barrier to enhance CNS chemotherapy. Expert Opin Investig Drugs 2001; 10:1809-18. [PMID: 11772287 DOI: 10.1517/13543784.10.10.1809] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The blood-brain barrier (BBB) to water-soluble drugs and macromolecules can be opened in vivo by infusing a hypertonic solution of arabinose or mannitol into the carotid artery for 30 sec. Opening involves widening of tight junctions between endothelial cells of the cerebrovasculature and is mediated by endothelial cell shrinkage, vascular dilatation associated with removal of water from brain, and modulation of the contractile state of the endothelial cytoskeleton and junctional proteins by increased intracellular calcium. A 10-fold increase in BBB permeability to intravascular substances, lasting about 10 min following osmotic exposure, reflects both increased diffusion and bulk fluid flow from blood into brain. Furthermore, recent evidence indicates that the duration of peak BBB opening can be extended beyond 30 min, by pre-treatment with a Na(+)/Ca(2+) channel blocker. In experimental animals, the osmotic method has been used to grant wide access to brain of water-soluble drugs, peptides, antibodies, boron compounds for neutron capture therapy, viral vectors for gene therapy and enzymes. Ongoing multi-centre clinical studies suggest that the method, when used with intra-arterially administered anticancer drugs, can prolong survival in patients with malignant brain tumours, with minimal morbidity. However, controlled clinical trials are critical to see if the osmotic procedure with intra-arterial drugs enhances survival in brain tumour patients compared with intra-arterial drug alone.
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Affiliation(s)
- S I Rapoport
- Brain Physiology and Metabolism Section, Bldg. 10, Rm. 6N 202, National Institute on Aging, National Institutes of Health, Bethesda, MD 20892, USA.
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98
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Temsamani J, Rousselle C, Rees AR, Scherrmann JM. Vector-mediated drug delivery to the brain. Expert Opin Biol Ther 2001; 1:773-82. [PMID: 11728213 DOI: 10.1517/14712598.1.5.773] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
As a consequence of the growing ageing population, many neurodegenerative diseases, cancer and infections of the brain will become more prevalent. Despite major advances in neuroscience, many potential therapeutic agents are denied access to the central nervous system (CNS) because of the existence of the blood-brain barrier (BBB). This barrier is formed by the endothelial cells of the brain capillaries and its primary characteristic is the impermeability of the capillary wall due to the presence of complex tight junctions and a low endocytic activity. The BBB behaves as a continuous lipid bilayer and prevents the passage of polar and lipid-insoluble substances. The BBB is, therefore, the major obstacle to drugs that are potentially useful for combating diseases affecting the CNS. Extensive efforts have been made to develop CNS drug delivery strategies in order to enhance delivery of therapeutic molecules across the BBB. The current challenge is to develop drug-delivery strategies that will allow the passage of therapeutic drugs through the BBB in a safe and effective manner. This review focuses specifically on the strategies developed to enhance drug delivery across the BBB with an emphasis on the vector-mediated strategy.
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Affiliation(s)
- J Temsamani
- Syntem, Parc Scientifique Georges Besse, 30000 Nîmes, France.
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99
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Sakaeda T, Tada Y, Sugawara T, Ryu T, Hirose F, Yoshikawa T, Hirano K, Kupczyk-Subotkowska L, Siahaan TJ, Audus KL, Stella VJ. Conjugation with L-Glutamate for in vivo brain drug delivery. J Drug Target 2001; 9:23-37. [PMID: 11378521 DOI: 10.3109/10611860108995630] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
In vitro studies have shown that conjugation of a model compound [p-di(hydroxyethyl)-amino-D-phenylalanine (D-MOD)] with L-Glu can improve D-MOD permeation through the bovine brain microvessel endothelial cell monolayers (Sakaeda et al., 2000). The transport of this D-MOD-L-Glu conjugate is facilitated by the L-Glu transport system. In this paper, we evaluate the in vivo brain delivery of model compounds (i.e. D-MOD, p-nitro-D-phenylalanine (p-nitro-D-Phe), 5,7-dichlorokynurenic acid (DCKA) and D-kyotorphin) and their L-Glu conjugates. DCKA was also conjugated with L-Asp and L-Gln amino acids. The analgesic activities of D-kyotorphin and its L-Glu conjugate were also evaluated. The results showed that the brain-to-plasma concentration ratio of D-MOD-L-Glu was higher than the D-MOD alone; however, the plasma concentration of both compounds were the same. The plasma concentration of p-nitro-D-Phe-L-Glu conjugate was higher than the parent p-nitro-D-Phe; however, the brain-to-plasma concentration ratio of p-nitro-D-Phe was higher than its conjugate. On the other hand, both DCKA and DCKA conjugates have a low brain-to-plasma concentration ratio due to their inability to cross the blood-brain barrier (BBB). The L-Asp and L-Glu conjugates of DCKA have elevated plasma concentrations relative to DCKA; however, the DCKA-L-Gln conjugate has the same plasma concentration as DCKA. For D-kyotorphin, both the parent and the L-Glu conjugate showed similar analgesic activity. In conclusion, conjugation of a non-permeable drug with L-Glu may improve the drug's brain delivery; however, this improvement may depend on the physicochemical and receptor binding properties of the conjugate.
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Affiliation(s)
- T Sakaeda
- Shionogi Research Laboratories, Shionogi & Co., Ltd., 5-12-4, Sagisu Fukushima-ku, Osaka, 553-0002, Japan
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