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Atkinson E, Dickman R. Growth factors and their peptide mimetics for treatment of traumatic brain injury. Bioorg Med Chem 2023; 90:117368. [PMID: 37331175 DOI: 10.1016/j.bmc.2023.117368] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/16/2023] [Accepted: 06/05/2023] [Indexed: 06/20/2023]
Abstract
Traumatic brain injury (TBI) is a leading cause of disability in adults, caused by a physical insult damaging the brain. Growth factor-based therapies have the potential to reduce the effects of secondary injury and improve outcomes by providing neuroprotection against glutamate excitotoxicity, oxidative damage, hypoxia, and ischemia, as well as promoting neurite outgrowth and the formation of new blood vessels. Despite promising evidence in preclinical studies, few neurotrophic factors have been tested in clinical trials for TBI. Translation to the clinic is not trivial and is limited by the short in vivo half-life of the protein, the inability to cross the blood-brain barrier and human delivery systems. Synthetic peptide mimetics have the potential to be used in place of recombinant growth factors, activating the same downstream signalling pathways, with a decrease in size and more favourable pharmacokinetic properties. In this review, we will discuss growth factors with the potential to modulate damage caused by secondary injury mechanisms following a traumatic brain injury that have been trialled in other indications including spinal cord injury, stroke and neurodegenerative diseases. Peptide mimetics of nerve growth factor (NGF), hepatocyte growth factor (HGF), glial cell line-derived growth factor (GDNF), brain-derived neurotrophic factor (BDNF), platelet-derived growth factor (PDGF) and fibroblast growth factor (FGF) will be highlighted, most of which have not yet been tested in preclinical or clinical models of TBI.
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Affiliation(s)
- Emily Atkinson
- School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK; UCL Centre for Nerve Engineering, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK.
| | - Rachael Dickman
- School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, UK.
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2
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Novel Hominid-Specific IAPP Isoforms: Potential Biomarkers of Early Alzheimer's Disease and Inhibitors of Amyloid Formation. Biomolecules 2023; 13:biom13010167. [PMID: 36671553 PMCID: PMC9856209 DOI: 10.3390/biom13010167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/23/2022] [Accepted: 01/09/2023] [Indexed: 01/15/2023] Open
Abstract
(1) Background and aims: Amyloidosis due to aggregation of amyloid-β (Aβ42) is a key pathogenic event in Alzheimer's disease (AD), whereas aggregation of mature islet amyloid polypeptide (IAPP37) in human islets leads to β-cell dysfunction. The aim of this study is to uncover potential biomarkers that might additionally point to therapy for early AD patients. (2) Methods: We used bioinformatic approach to uncover novel IAPP isoforms and developed a quantitative selective reaction monitoring (SRM) proteomic assay to measure their peptide levels in human plasma and CSF from individuals with early AD and controls, as well as postmortem cerebrum of clinical confirmed AD and controls. We used Thioflavin T amyloid reporter assay to measure the IAPP isoform fibrillation propensity and anti-amyloid potential against aggregation of Aβ42 and IAPP37. (3) Results: We uncovered hominid-specific IAPP isoforms: hIAPPβ, which encodes an elongated propeptide, and hIAPPγ, which is processed to mature IAPP25 instead of IAPP37. We found that hIAPPβ was significantly reduced in the plasma of AD patients with the accuracy of 89%. We uncovered that IAPP25 and a GDNF derived DNSP11 were nonaggregating peptides that inhibited the aggregation of IAPP37 and Aβ42. (4) Conclusions: The novel peptides derived from hIAPP isoforms have potential to serve as blood-derived biomarkers for early AD and be developed as peptide based anti-amyloid medicine.
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3
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Shamadykova DV, Panteleev DY, Kust NN, Savchenko EA, Rybalkina EY, Revishchin AV, Pavlova GV. Neuroinductive properties of mGDNF depend on the producer, E. Coli or human cells. PLoS One 2021; 16:e0258289. [PMID: 34634077 PMCID: PMC8504721 DOI: 10.1371/journal.pone.0258289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 07/11/2021] [Indexed: 12/04/2022] Open
Abstract
The glial cell line-derived neurotrophic factor (GDNF) is involved in the survival of dopaminergic neurons. Besides, GDNF can also induce axonal growth and creation of new functional synapses. GDNF potential is promising for translation to treat diseases associated with neuronal death: neurodegenerative disorders, ischemic stroke, and cerebral or spinal cord damages. Unproductive clinical trials of GDNF for Parkinson's disease treatment have induced to study this failure. A reason could be due to irrelevant producer cells that cannot perform the required post-translational modifications. The biological activity of recombinant mGDNF produced by E. coli have been compared with mGDNF produced by human cells HEK293. mGDNF variants were tested with PC12 cells, rat embryonic spinal ganglion cells, and SH-SY5Y human neuroblastoma cells in vitro as well as with a mouse model of the Parkinson's disease in vivo. Both in vitro and in vivo the best neuro-inductive ability belongs to mGDNF produced by HEK293 cells. Keywords: GDNF, neural differentiation, bacterial and mammalian expression systems, cell cultures, model of Parkinson's disease.
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Affiliation(s)
- Dzhirgala V. Shamadykova
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Dmitry Y. Panteleev
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
| | - Nadezhda N. Kust
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | | | | | - Alexander V. Revishchin
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
| | - Galina V. Pavlova
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
- Burdenko Neurosurgical Institute, Moscow, Russia
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia
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Roos BB, Teske JJ, Bhallamudi S, Pabelick CM, Sathish V, Prakash YS. Neurotrophin Regulation and Signaling in Airway Smooth Muscle. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1304:109-121. [PMID: 34019266 PMCID: PMC11042712 DOI: 10.1007/978-3-030-68748-9_7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Structural and functional aspects of bronchial airways are key throughout life and play critical roles in diseases such as asthma. Asthma involves functional changes such as airway irritability and hyperreactivity, as well as structural changes such as enhanced cellular proliferation of airway smooth muscle (ASM), epithelium, and fibroblasts, and altered extracellular matrix (ECM) and fibrosis, all modulated by factors such as inflammation. There is now increasing recognition that disease maintenance following initial triggers involves a prominent role for resident nonimmune airway cells that secrete growth factors with pleiotropic autocrine and paracrine effects. The family of neurotrophins may be particularly relevant in this regard. Long recognized in the nervous system, classical neurotrophins such as brain-derived neurotrophic factor (BDNF) and nonclassical ligands such as glial-derived neurotrophic factor (GDNF) are now known to be expressed and functional in non-neuronal systems including lung. However, the sources, targets, regulation, and downstream effects are still under investigation. In this chapter, we discuss current state of knowledge and future directions regarding BDNF and GDNF in airway physiology and on pathophysiological contributions in asthma.
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Affiliation(s)
- Benjamin B Roos
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - Jacob J Teske
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
| | - Sangeeta Bhallamudi
- Department of Pharmaceutical Sciences, North Dakota State University, Fargo, ND, USA
| | - Christina M Pabelick
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Venkatachalem Sathish
- Department of Pharmaceutical Sciences, North Dakota State University, Fargo, ND, USA
| | - Y S Prakash
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN, USA.
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA.
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GDNF synthesis, signaling, and retrograde transport in motor neurons. Cell Tissue Res 2020; 382:47-56. [PMID: 32897420 PMCID: PMC7529617 DOI: 10.1007/s00441-020-03287-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 08/18/2020] [Indexed: 02/06/2023]
Abstract
Glial cell line–derived neurotrophic factor (GDNF) is a 134 amino acid protein belonging in the GDNF family ligands (GFLs). GDNF was originally isolated from rat glial cell lines and identified as a neurotrophic factor with the ability to promote dopamine uptake within midbrain dopaminergic neurons. Since its discovery, the potential neuroprotective effects of GDNF have been researched extensively, and the effect of GDNF on motor neurons will be discussed herein. Similar to other members of the TGF-β superfamily, GDNF is first synthesized as a precursor protein (pro-GDNF). After a series of protein cleavage and processing, the 211 amino acid pro-GDNF is finally converted into the active and mature form of GDNF. GDNF has the ability to trigger receptor tyrosine kinase RET phosphorylation, whose downstream effects have been found to promote neuronal health and survival. The binding of GDNF to its receptors triggers several intracellular signaling pathways which play roles in promoting the development, survival, and maintenance of neuron-neuron and neuron-target tissue interactions. The synthesis and regulation of GDNF have been shown to be altered in many diseases, aging, exercise, and addiction. The neuroprotective effects of GDNF may be used to develop treatments and therapies to ameliorate neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS). In this review, we provide a detailed discussion of the general roles of GDNF and its production, delivery, secretion, and neuroprotective effects on motor neurons within the mammalian neuromuscular system.
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Small Molecules and Peptides Targeting Glial Cell Line-Derived Neurotrophic Factor Receptors for the Treatment of Neurodegeneration. Int J Mol Sci 2020; 21:ijms21186575. [PMID: 32911810 PMCID: PMC7554781 DOI: 10.3390/ijms21186575] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/31/2020] [Accepted: 09/06/2020] [Indexed: 12/14/2022] Open
Abstract
Glial cell line-derived neurotrophic factor (GDNF) family ligands (GFLs) are able to promote the survival of multiple neuronal populations in the body and, therefore, hold considerable promise for disease-modifying treatments of diseases and conditions caused by neurodegeneration. Available data reveal the potential of GFLs for the therapy of Parkinson's disease, neuropathic pain and diseases caused by retinal degeneration but, also, amyotrophic lateral sclerosis and, possibly, Alzheimer's disease. Despite promising data collected in preclinical models, clinical translation of GFLs is yet to be conducted. The main reasons for the limited success of GFLs clinical development are the poor pharmacological characteristics of GFL proteins, such as the inability of GFLs to cross tissue barriers, poor diffusion in tissues, biphasic dose-response and activation of several receptors in the organism in different cell types, along with ethical limitations on patients' selection in clinical trials. The development of small molecules selectively targeting particular GFL receptors with improved pharmacokinetic properties can overcome many of the difficulties and limitations associated with the clinical use of GFL proteins. The current review lists several strategies to target the GFL receptor complex with drug-like molecules, discusses their advantages, provides an overview of available chemical scaffolds and peptides able to activate GFL receptors and describes the effects of these molecules in cultured cells and animal models.
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Gash DM, Gerhardt GA, Bradley LH, Wagner R, Slevin JT. GDNF clinical trials for Parkinson's disease: a critical human dimension. Cell Tissue Res 2020; 382:65-70. [PMID: 32830288 DOI: 10.1007/s00441-020-03269-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 07/29/2020] [Indexed: 01/02/2023]
Affiliation(s)
- Don Marshall Gash
- Department of Neuroscience, Chandler Medical Center, University of Kentucky, Lexington, KY, USA. .,College of Medicine, Lewis Honors College, University of Kentucky, Lexington, KY, USA.
| | - Greg A Gerhardt
- Department of Neuroscience, Chandler Medical Center, University of Kentucky, Lexington, KY, USA.,Department of Neurology, Chandler Medical Center, University of Kentucky, Lexington, KY, USA
| | - Luke H Bradley
- Department of Neuroscience, Chandler Medical Center, University of Kentucky, Lexington, KY, USA
| | - Renee Wagner
- Department of Neurology, Chandler Medical Center, University of Kentucky, Lexington, KY, USA
| | - John T Slevin
- Department of Neurology, Chandler Medical Center, University of Kentucky, Lexington, KY, USA
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Spatial and temporal immunoreactivity in the rat brain using an affinity purified polyclonal antibody to DNSP-11. J Chem Neuroanat 2019; 100:101664. [PMID: 31394198 DOI: 10.1016/j.jchemneu.2019.101664] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 07/30/2019] [Accepted: 08/03/2019] [Indexed: 01/21/2023]
Abstract
DNSP-11 antibody signal was investigated in perfusion fixated Fischer 344 rat brains by immunohistochemistry with a custom, affinity purified polyclonal antibody. The DNSP-11-antibody signal was differentially localized from the mature GDNF protein both spatially and temporally. In the mesencephalon of post-natal day 10 animals, when GDNF is maximally expressed, DNSP-11 and GDNF antibody immunoreactivities co-localize extensively but not exclusively. In adult 3-month-old animals, GDNF expression is markedly reduced while the DNSP-11 signal remains intense. DNSP-11-antibody signal was present in the 3-month-old rat brain with signal in the substantia nigra, ventral tegmental area, dentate gyrus of the hippocampus, with the strongest signal observed in the locus ceruleus where GDNF is not expressed. While amino acid sequence homologues such as NPY and Tfg do exist, binding patterns reported in the literature of do not recapitulate the immunoreactive patterns observed for the DNSP-11-antibody signal.
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Penttinen AM, Parkkinen I, Voutilainen MH, Koskela M, Bäck S, Their A, Richie CT, Domanskyi A, Harvey BK, Tuominen RK, Nevalaita L, Saarma M, Airavaara M. Pre-α-pro-GDNF and Pre-β-pro-GDNF Isoforms Are Neuroprotective in the 6-hydroxydopamine Rat Model of Parkinson's Disease. Front Neurol 2018; 9:457. [PMID: 29973907 PMCID: PMC6019446 DOI: 10.3389/fneur.2018.00457] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 05/29/2018] [Indexed: 11/13/2022] Open
Abstract
Glial cell line-derived neurotrophic factor (GDNF) is one of the most studied neurotrophic factors. GDNF has two splice isoforms, full-length pre-α-pro-GDNF (α-GDNF) and pre-β-pro-GDNF (β-GDNF), which has a 26 amino acid deletion in the pro-region. Thus far, studies have focused solely on the α-GDNF isoform, and nothing is known about the in vivo effects of the shorter β-GDNF variant. Here we compare for the first time the effects of overexpressed α-GDNF and β-GDNF in non-lesioned rat striatum and the partial 6-hydroxydopamine lesion model of Parkinson's disease. GDNF isoforms were overexpressed with their native pre-pro-sequences in the striatum using an adeno-associated virus (AAV) vector, and the effects on motor performance and dopaminergic phenotype of the nigrostriatal pathway were assessed. In the non-lesioned striatum, both isoforms increased the density of dopamine transporter-positive fibers at 3 weeks after viral vector delivery. Although both isoforms increased the activity of the animals in cylinder assay, only α-GDNF enhanced the use of contralateral paw. Four weeks later, the striatal tyrosine hydroxylase (TH)-immunoreactivity was decreased in both α-GDNF and β-GDNF treated animals. In the neuroprotection assay, both GDNF splice isoforms increased the number of TH-immunoreactive cells in the substantia nigra but did not promote behavioral recovery based on amphetamine-induced rotation or cylinder assays. Thus, the shorter GDNF isoform, β-GDNF, and the full-length α-isoform have comparable neuroprotective efficacy on dopamine neurons of the nigrostriatal circuitry.
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Affiliation(s)
- Anna-Maija Penttinen
- HiLIFE Unit, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Ilmari Parkkinen
- HiLIFE Unit, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Merja H Voutilainen
- HiLIFE Unit, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Maryna Koskela
- HiLIFE Unit, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Susanne Bäck
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Anna Their
- HiLIFE Unit, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Christopher T Richie
- National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, United States
| | - Andrii Domanskyi
- HiLIFE Unit, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Brandon K Harvey
- National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, United States
| | - Raimo K Tuominen
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Liina Nevalaita
- HiLIFE Unit, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Mart Saarma
- HiLIFE Unit, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Mikko Airavaara
- HiLIFE Unit, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
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Popova NK, Ilchibaeva TV, Naumenko VS. Neurotrophic factors (BDNF and GDNF) and the serotonergic system of the brain. BIOCHEMISTRY (MOSCOW) 2017; 82:308-317. [DOI: 10.1134/s0006297917030099] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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11
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Stenslik MJ, Potts LF, Sonne JWH, Cass WA, Turchan-Cholewo J, Pomerleau F, Huettl P, Ai Y, Gash DM, Gerhardt GA, Bradley LH. Methodology and effects of repeated intranasal delivery of DNSP-11 in a rat model of Parkinson's disease. J Neurosci Methods 2015; 251:120-9. [PMID: 25999268 DOI: 10.1016/j.jneumeth.2015.05.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 05/11/2015] [Accepted: 05/11/2015] [Indexed: 01/21/2023]
Abstract
BACKGROUND To circumvent the challenges associated with delivering large compounds directly to the brain for the treatment of Parkinson's disease (PD), non-invasive procedures utilizing smaller molecules with protective and/or restorative actions on dopaminergic neurons are needed. NEW METHOD We developed a methodology for evaluating the effects of a synthetic neuroactive peptide, DNSP-11, on the nigrostriatal system using repeated intranasal delivery in both normal and a unilateral 6-hydroxydopamine (6-OHDA) lesion rat model of PD. RESULTS Normal rats repeatedly administered varying doses of DNSP-11 intranasally for 3 weeks exhibited a significant increase in dopamine (DA) turnover in both the striatum and substantia nigra (SN) at 300μg, suggestive of a stimulative effect of the dopaminergic system. Additionally, a protective effect was observed following repeated intranasal administration in 6-OHDA lesioned rats, as suggested by: a significant decrease in d-amphetamine-induced rotation at 2 weeks; a decrease in DA turnover in the lesioned striatum; and an increased sparing of tyrosine hydroxylase (TH) positive (+) neurons in a specific sub-region of the lesioned substantia nigra pars compacta (SNpc). Finally, tracer studies showed (125)I-DNSP-11 distributed diffusely throughout the brain, including the striatum and SN, as quickly as 30min after a single intranasal dose. COMPARISON WITH EXISTING METHODS The results of bilateral intranasal administration of DNSP-11 are compared to our unilateral single infusion studies to the brain in rats. CONCLUSIONS These studies support that DNSP-11 can be delivered intranasally and maintain its neuroactive properties in both normal rats and in a unilateral 6-OHDA rat model of PD.
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Affiliation(s)
- Mallory J Stenslik
- Department of Anatomy & Neurobiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Lisa F Potts
- Department of Anatomy & Neurobiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - James W H Sonne
- Department of Anatomy & Neurobiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Wayne A Cass
- Department of Anatomy & Neurobiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Jadwiga Turchan-Cholewo
- Department of Anatomy & Neurobiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Francois Pomerleau
- Department of Anatomy & Neurobiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Peter Huettl
- Department of Anatomy & Neurobiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Yi Ai
- Department of Anatomy & Neurobiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Don M Gash
- Department of Anatomy & Neurobiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Greg A Gerhardt
- Department of Anatomy & Neurobiology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Luke H Bradley
- Department of Anatomy & Neurobiology, University of Kentucky College of Medicine, Lexington, KY, USA; Department of Molecular & Cellular Biochemistry and Center of Structural Biology, University of Kentucky College of Medicine, Lexington, KY, USA.
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Fuqua JL, Littrell OM, Lundblad M, Turchan-Cholewo J, Abdelmoti LG, Galperin E, Bradley LH, Cass WA, Gash DM, Gerhardt GA. Dynamic changes in dopamine neuron function after DNSP-11 treatment: effects in vivo and increased ERK 1/2 phosphorylation in vitro. Peptides 2014; 54:1-8. [PMID: 24406899 PMCID: PMC3989369 DOI: 10.1016/j.peptides.2013.12.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 12/09/2013] [Accepted: 12/10/2013] [Indexed: 12/14/2022]
Abstract
Glial cell-line derived neurotrophic factor (GDNF) has demonstrated robust effects on dopamine (DA) neuron function and survival. A post-translational processing model of the human GDNF proprotein theorizes the formation of smaller, amidated peptide(s) from the proregion that exhibit neurobiological function, including an 11-amino-acid peptide named dopamine neuron stimulating peptide-11 (DNSP-11). A single treatment of DNSP-11 was delivered to the substantia nigra in the rat to investigate effects on DA-neuron function. Four weeks after treatment, potassium (K+) and D-amphetamine evoked DA release were studied in the striatum using microdialysis. There were no significant changes in DA-release after DNSP-11 treatment determined by microdialysis. Dopamine release was further examined in discrete regions of the striatum using high-speed chronoamperometry at 1-, 2-, and 4-weeks after DNSP-11 treatment. Two weeks after DNSP-11 treatment, potassium-evoked DA release was increased in specific subregions of the striatum. However, spontaneous locomotor activity was unchanged by DNSP-11 treatment. In addition, we show that a single treatment of DNSP-11 in the MN9D dopaminergic neuronal cell line results in phosphorylation of ERK1/2, which suggests a novel cellular mechanism responsible for increases in DA function.
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Affiliation(s)
- Joshua L Fuqua
- Department of Anatomy and Neurobiology, Parkinson's Disease Translational Center of Excellence, University of Kentucky Medical Center, MN 206 Medical Sciences Building, 800 Rose St., Lexington, KY 40536, USA
| | - Ofelia M Littrell
- Department of Anatomy and Neurobiology, Parkinson's Disease Translational Center of Excellence, University of Kentucky Medical Center, MN 206 Medical Sciences Building, 800 Rose St., Lexington, KY 40536, USA
| | - Martin Lundblad
- Experimental Medical Science, Neurobiology, Lund University, BMCA11, 221, 84 Lund, Sweden
| | - Jadwiga Turchan-Cholewo
- Department of Anatomy and Neurobiology, Parkinson's Disease Translational Center of Excellence, University of Kentucky Medical Center, MN 206 Medical Sciences Building, 800 Rose St., Lexington, KY 40536, USA
| | - Lina G Abdelmoti
- Department of Molecular & Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY, USA; Center of Structural Biology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Emilia Galperin
- Department of Molecular & Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY, USA; Center of Structural Biology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Luke H Bradley
- Department of Anatomy and Neurobiology, Parkinson's Disease Translational Center of Excellence, University of Kentucky Medical Center, MN 206 Medical Sciences Building, 800 Rose St., Lexington, KY 40536, USA; Department of Molecular & Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY, USA; Center of Structural Biology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Wayne A Cass
- Department of Anatomy and Neurobiology, Parkinson's Disease Translational Center of Excellence, University of Kentucky Medical Center, MN 206 Medical Sciences Building, 800 Rose St., Lexington, KY 40536, USA
| | - Don M Gash
- Department of Anatomy and Neurobiology, Parkinson's Disease Translational Center of Excellence, University of Kentucky Medical Center, MN 206 Medical Sciences Building, 800 Rose St., Lexington, KY 40536, USA
| | - Greg A Gerhardt
- Department of Anatomy and Neurobiology, Parkinson's Disease Translational Center of Excellence, University of Kentucky Medical Center, MN 206 Medical Sciences Building, 800 Rose St., Lexington, KY 40536, USA.
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The proform of glia cell line-derived neurotrophic factor: a potentially biologically active protein. Mol Neurobiol 2013; 49:234-50. [PMID: 23934644 DOI: 10.1007/s12035-013-8515-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 07/10/2013] [Indexed: 12/24/2022]
Abstract
Growing evidences have revealed that the proforms of several neurotrophins including nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT3), by binding to p75 neurotrophin receptor and sortilin, could induce neuronal apoptosis and are implicated in the pathogenesis of various neurodegenerative diseases. The glial cell line-derived neurotrophic factor (GDNF), one of the most potent useful neurotrophic factors for the treatment of Parkinson's disease (PD), is firstly synthesized as the proform (proGDNF) like other neurotrophin NGF, BDNF, and NT3. However, little is known about proGDNF expression and secretion under physiological as well as pathological states in vivo or in vitro. In this study, we investigated the expression profile and dynamic changes of proGDNF in brains of aging and PD animal models, with the interesting finding that proGDNF was a predominant form of GDNF with molecular weight of about 36 kDa by reducing and nonreducing immunoblots in adult brains and was unregulated in the aging, lipopolysaccharide (LPS), and 1-methyl-4-phenyl- 1,2,3,6-tetrahydropyridine (MPTP) insult. We further provided direct evidence that accompanied activation of primary astrocytes as well as C6 cell line induced by LPS stimulation, proGDNF was increasingly synthesized and released as the uncleaved form in cell culture. Taken together, our results strongly suggest that proGDNF may be a biologically active protein and has specific effects on the cells close to its secreting site, and a potentially important role of proGDNF signaling in the brains, in the glia-neuronal interaction or in the pathogenesis of PD, should merit further investigation.
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14
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McCullough MJ, Gyorkos AM, Spitsbergen JM. Short-term exercise increases GDNF protein levels in the spinal cord of young and old rats. Neuroscience 2013; 240:258-68. [PMID: 23500094 DOI: 10.1016/j.neuroscience.2013.02.063] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 02/12/2013] [Accepted: 02/27/2013] [Indexed: 12/29/2022]
Abstract
Neurotrophic factors may play a role in exercise-induced neuroprotective effects, however it is not known if exercise mediates changes in glial cell line-derived neurotrophic factor (GDNF) protein levels in the spinal cord. The aim of the current study was to determine if 2 weeks of exercise alters GDNF protein content in the lumbar spinal cord of young and old rats. GDNF protein was quantified via an enzyme-linked immunosorbent assay and Western blot. Immunohistochemical analysis localized GDNF in choline acetyltransferase (ChAT)-positive motor neurons and cell body areas were measured. Involuntary running in the young animals appeared to elicit the greatest increase in GDNF protein content (sixfold increase), followed by swimming (threefold increase) and voluntary running (twofold increase); however there was no significant difference between the modalities of exercise. Low-intensity running of the old animals significantly increased GDNF protein content in the spinal cord. Both young and old exercised animals showed a doubling in ChAT-positive motor neuron cell body areas. These results suggest that GDNF protein content in the spinal cord is modulated by exercise.
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Affiliation(s)
- M J McCullough
- Department of Biological Sciences, Western Michigan University, 1903 W. Michigan Avenue, Kalamazoo, MI 49008-5410, USA.
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Littrell OM, Fuqua JL, Richardson AD, Turchan-Cholewo J, Hascup ER, Huettl P, Pomerleau F, Bradley LH, Gash DM, Gerhardt GA. A synthetic five amino acid propeptide increases dopamine neuron differentiation and neurochemical function. Neuropeptides 2013; 47:43-9. [PMID: 22981157 PMCID: PMC3558608 DOI: 10.1016/j.npep.2012.08.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Revised: 07/31/2012] [Accepted: 08/07/2012] [Indexed: 10/27/2022]
Abstract
A major consequence of Parkinson's disease (PD) involves the loss of dopaminergic neurons in the substantia nigra (SN) and a subsequent loss of dopamine (DA) in the striatum. We have shown that glial cell line-derived neurotrophic factor (GDNF) shows robust restorative and protective effects for DA neurons in rats, non-human primates and possibly in humans. Despite GDNF's therapeutic potential, its clinical value has been questioned due to its limited diffusion to target areas from its large size and chemical structure. Several comparatively smaller peptides are thought to be generated from the prosequence. A five amino-acid peptide, dopamine neuron stimulating peptide-5 (DNSP-5), has been proposed to demonstrate biological activity relevant to neurodegenerative disease. We tested the in vitro effects of DNSP-5 in primary dopaminergic neurons dissected from the ventral mesencephalon of E14 Sprague Dawley rat fetuses. Cells were treated with several doses (0.03, 0.1, 1.0, 10.0 ng/mL) of GDNF, DNSP-5, or an equivalent volume of citrate buffer (vehicle). Morphological features of tyrosine hydroxylase positive neurons were quantified for each dose. DNSP-5 significantly increased (p < 0.001) all differentiation parameters compared to citrate vehicle (at one or more dose). For in vivo studies, a unilateral DNSP-5 treatment (30 μg) was administered directly to the SN. Microdialysis in the ipsilateral striatum was performed 28 days after treatment to determine extracellular levels of DA and its primary metabolites (3,4-dihydroxyphenylacetic acid and homovanillic acid). A single treatment significantly increased (~66%) extracellular DA levels compared to vehicle, while DA metabolites were unchanged. Finally, the protective effects of DNSP-5 against staurosporine-induced cytotoxicity were investigated in a neuronal cell line showing substantial protection by DNSP-5. Altogether, these studies strongly indicate biological activity of DNSP-5 and suggest that DNSP-5 has neurotrophic-like properties that may be relevant to the treatment of neurodegenerative diseases like PD.
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Affiliation(s)
- OM Littrell
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, 800 Rose Street, Lexington, KY, 40536
| | - JL Fuqua
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, 800 Rose Street, Lexington, KY, 40536
| | - AD Richardson
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, 800 Rose Street, Lexington, KY, 40536
| | - J. Turchan-Cholewo
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, 800 Rose Street, Lexington, KY, 40536
| | - ER Hascup
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, 800 Rose Street, Lexington, KY, 40536
| | - P Huettl
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, 800 Rose Street, Lexington, KY, 40536
| | - F Pomerleau
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, 800 Rose Street, Lexington, KY, 40536
| | - LH Bradley
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, 800 Rose Street, Lexington, KY, 40536
- Department of Molecular & Cellular Biochemistry and the Center of Structural Biology, University of Kentucky College of Medicine, 800 Rose Street, Lexington, KY, 40536
| | - DM Gash
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, 800 Rose Street, Lexington, KY, 40536
| | - GA Gerhardt
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, 800 Rose Street, Lexington, KY, 40536
- Corresponding author contact: Dr. Greg A. Gerhardt, 306 Davis Mills Bldg., 800 Rose Street, Lexington, KY 40536-0098, (), Phone: 1+ 859.323.4531, Fax: 1+ 859.257.5310
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Piccinini E, Kalkkinen N, Saarma M, Runeberg-Roos P. Glial cell line-derived neurotrophic factor: characterization of mammalian posttranslational modifications. Ann Med 2013; 45:66-73. [PMID: 23305235 DOI: 10.3109/07853890.2012.663927] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
INTRODUCTION Although glial cell line-derived neurotrophic factor (GDNF) has a strong clinical potential, little is known of how the posttranslational modifications of GDNF affect its biological activity and therapeutic potential. In mammalian cells GDNF is synthesized as a preproprotein. During secretion GDNF dimerizes, folds with -S-S- bonds, is modified by N-linked glycosylation, and undergoes proteolytic processing. After production in E. coli, unglycosylated GDNF is renaturated in vitro. Nevertheless, GDNF from E. coli was used in Parkinson's disease-related clinical trials. MATERIAL AND METHODS Constructs encoding variants of human GDNF were generated and expressed in mammalian cells. The proteins were analysed by SDS-PAGE, Western blotting, RET-phosphorylation assays, and N-terminal sequencing. The stability of mammalian GDNF was compared to commercial GDNF produced in E. coli. RESULTS Posttranslational processing of mammalian GDNF depends on the expression conditions. Two forms of GDNF with different N-termini are formed. GDNF without a prosequence is secreted and biologically active. GDNF is modified by N-linked glycosylation at one (Asn(49)) out of two consensus sites. N-linked glycosylation aids proteolytic processing of GDNF. Both glycosylated and unglycosylated GDNF from mammalian cells are more stable than GDNF from E. coli. DISCUSSION Posttranslational modifications of GDNF influence its stability, which may be critical for its clinical use.
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Affiliation(s)
- Elisa Piccinini
- Institute of Biotechnology, University of Helsinki, PB 56 Viikinkaari 9, SF-00014, University of Helsinki, Finland
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Airavaara M, Pletnikova O, Doyle ME, Zhang YE, Troncoso JC, Liu QR. Identification of novel GDNF isoforms and cis-antisense GDNFOS gene and their regulation in human middle temporal gyrus of Alzheimer disease. J Biol Chem 2011; 286:45093-102. [PMID: 22081608 DOI: 10.1074/jbc.m111.310250] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Primate-specific genes and isoforms could provide insight into human brain diseases. Our bioinformatic analysis revealed that there are possibly five isoforms of human GDNF gene with different pre- and pro-regions by inter- and intra-exon splicing. By using TaqMan primer probe sets, designed between exons, we verified the expression of all isoforms. Furthermore, a novel GDNFOS gene was found to be transcribed from the opposite strand of GDNF gene. GDNFOS gene has four exons that are spliced into different isoforms. GDNFOS1 and GDNFOS2 are long noncoding RNAs, and GDNFOS3 encodes a protein of 105 amino acids. To study human GDNF and GDNFOS regulation in neurodegenerative diseases, the protein and mRNA levels were measured by Western blot and RT-quantitative PCR, respectively, in postmortem middle temporal gyrus (MTG) of Alzheimer disease (AD) and Huntington disease (HD) patients in comparison with those of normal controls. In the MTG of AD patients, the mature GDNF peptide was down-regulated; however, the transcript of GDNF isoform from human exon 2 was up-regulated, whereas that of the conserved isoform from exon 1 remained unchanged in comparison with those of normal controls. In contrast, the mature GDNF peptide and the isoform mRNA levels were not changed in the MTG of HD. The findings of novel GDNF and GDNFOS isoforms and differences in tissue expression patterns dysregulated in AD brains may further reveal the role of endogenous GDNF in human brain diseases.
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Affiliation(s)
- Mikko Airavaara
- Neural Protection and Regeneration Section, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Department of Health and Social Services, Baltimore, Maryland21224, USA
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Kelps KA, Turchan-Cholewo J, Hascup ER, Taylor TL, Gash DM, Gerhardt GA, Bradley LH. Evaluation of the physical and in vitro protective activity of three synthetic peptides derived from the pro- and mature GDNF sequence. Neuropeptides 2011; 45:213-8. [PMID: 21507484 PMCID: PMC3091812 DOI: 10.1016/j.npep.2011.03.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2011] [Revised: 03/21/2011] [Accepted: 03/22/2011] [Indexed: 12/12/2022]
Abstract
Recently, a small 11-amino acid amidated peptide, dopamine neuron stimulating peptide-11 (DNSP-11), was shown to exert neurotrophic-like actions on primary dopaminergic neurons and in parkinsonian rat models. This suggests smaller neurotrophic-like molecules may be deliverable and modifiable for therapeutic use. Here we evaluate the molecular and cellular protection properties of DNSP-11 and two other amidated-peptides, a 5-mer (DNSP-5) and a 17-mer (DNSP-17), hypothesized to be endoproteolytically processed from the pro- and mature glial cell line-derived neurotrophic factor (GDNF) protein sequence, respectively. Far-UV circular dichroism spectra show that the three DNSPs are soluble and act independently in vitro. Reverse phase HPLC and mass spectrometry analysis show that the three peptides are stable for one month at a variety of storage and experimental conditions. To gain insight into their biodistribution properties in the brain, we used affinity chromatography to show that DNSP-17 binds heparin equally as tight as GDNF, whereas DNSP-5 and DNSP-11 do not bind heparin, which should facilitate their delivery in vivo. Finally, we present data showing that DNSP-11 provides dose-dependent protection of HEK-293 cells from staurosporine and 3-nitropropionate (3-NP) cytotoxicity, thereby supporting its broad mitochondrial-protective properties.
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Affiliation(s)
- Kristen A. Kelps
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, Lexington, KY, U.S.A
| | - Jadwiga Turchan-Cholewo
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, Lexington, KY, U.S.A
| | - Erin R. Hascup
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, Lexington, KY, U.S.A
| | - Tiffany L. Taylor
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, Lexington, KY, U.S.A
| | - Don M. Gash
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, Lexington, KY, U.S.A
| | - Greg A. Gerhardt
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, Lexington, KY, U.S.A
| | - Luke H. Bradley
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson’s Disease Research Center of Excellence, University of Kentucky College of Medicine, Lexington, KY, U.S.A
- Department of Molecular & Cellular Biochemistry and the Center of Structural Biology, University of Kentucky College of Medicine, Lexington, KY, U.S.A
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Bradley LH, Fuqua J, Richardson A, Turchan-Cholewo J, Ai Y, Kelps KA, Glass JD, He X, Zhang Z, Grondin R, Littrell OM, Huettl P, Pomerleau F, Gash DM, Gerhardt GA. Dopamine neuron stimulating actions of a GDNF propeptide. PLoS One 2010; 5:e9752. [PMID: 20305789 PMCID: PMC2841203 DOI: 10.1371/journal.pone.0009752] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2009] [Accepted: 02/20/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Neurotrophic factors, such as glial cell line-derived neurotrophic factor (GDNF), have shown great promise for protection and restoration of damaged or dying dopamine neurons in animal models and in some Parkinson's disease (PD) clinical trials. However, the delivery of neurotrophic factors to the brain is difficult due to their large size and poor bio-distribution. In addition, developing more efficacious trophic factors is hampered by the difficulty of synthesis and structural modification. Small molecules with neurotrophic actions that are easy to synthesize and modify to improve bioavailability are needed. METHODS AND FINDINGS Here we present the neurobiological actions of dopamine neuron stimulating peptide-11 (DNSP-11), an 11-mer peptide from the proGDNF domain. In vitro, DNSP-11 supports the survival of fetal mesencephalic neurons, increasing both the number of surviving cells and neuritic outgrowth. In MN9D cells, DNSP-11 protects against dopaminergic neurotoxin 6-hydroxydopamine (6-OHDA)-induced cell death, significantly decreasing TUNEL-positive cells and levels of caspase-3 activity. In vivo, a single injection of DNSP-11 into the normal adult rat substantia nigra is taken up rapidly into neurons and increases resting levels of dopamine and its metabolites for up to 28 days. Of particular note, DNSP-11 significantly improves apomorphine-induced rotational behavior, and increases dopamine and dopamine metabolite tissue levels in the substantia nigra in a rat model of PD. Unlike GDNF, DNSP-11 was found to block staurosporine- and gramicidin-induced cytotoxicity in nutrient-deprived dopaminergic B65 cells, and its neuroprotective effects included preventing the release of cytochrome c from mitochondria. CONCLUSIONS Collectively, these data support that DNSP-11 exhibits potent neurotrophic actions analogous to GDNF, making it a viable candidate for a PD therapeutic. However, it likely signals through pathways that do not directly involve the GFRalpha1 receptor.
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Affiliation(s)
- Luke H Bradley
- Department of Anatomy & Neurobiology and the Morris K. Udall Parkinson's Disease Research Center of Excellence, University of Kentucky College of Medicine, Lexington, Kentucky, United States of America.
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Oh-hashi K, Ito M, Tanaka T, Hirata Y, Kiuchi K. Biosynthesis, processing, and secretion of glial cell line-derived neurotrophic factor in astroglial cells. Mol Cell Biochem 2008; 323:1-7. [DOI: 10.1007/s11010-008-9958-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Accepted: 10/28/2008] [Indexed: 12/01/2022]
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