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Navaee F, Renaud P, Piacentini N, Durand M, Bayat DZ, Ledroit D, Heub S, Boder-Pasche S, Kleger A, Braschler T, Weder G. Toward a Physiologically Relevant 3D Helicoidal-Oriented Cardiac Model: Simultaneous Application of Mechanical Stimulation and Surface Topography. Bioengineering (Basel) 2023; 10:bioengineering10020266. [PMID: 36829760 PMCID: PMC9952807 DOI: 10.3390/bioengineering10020266] [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: 01/04/2023] [Revised: 02/10/2023] [Accepted: 02/15/2023] [Indexed: 02/22/2023] Open
Abstract
Myocardium consists of cardiac cells that interact with their environment through physical, biochemical, and electrical stimulations. The physiology, function, and metabolism of cardiac tissue are affected by this dynamic structure. Within the myocardium, cardiomyocytes' orientations are parallel, creating a dominant orientation. Additionally, local alignments of fibers, along with a helical organization, become evident at the macroscopic level. For the successful development of a reliable in vitro cardiac model, evaluation of cardiac cells' behavior in a dynamic microenvironment, as well as their spatial architecture, is mandatory. In this study, we hypothesize that complex interactions between long-term contraction boundary conditions and cyclic mechanical stimulation may provide a physiological mechanism to generate off-axis alignments in the preferred mechanical stretch direction. This off-axis alignment can be engineered in vitro and, most importantly, mirrors the helical arrangements observed in vivo. For this purpose, uniaxial mechanical stretching of dECM-fibrin hydrogels was performed on pre-aligned 3D cultures of cardiac cells. In view of the potential development of helical structures similar to those in native hearts, the possibility of generating oblique alignments ranging between 0° and 90° was explored. Indeed, our investigations of cell alignment in 3D, employing both mechanical stimulation and groove constraint, provide a reliable mechanism for the generation of helicoidal structures in the myocardium. By combining cyclic stretch and geometric alignment in grooves, an intermediate angle toward favored direction can be achieved experimentally: while cyclic stretch produces a perpendicular orientation, geometric alignment is associated with a parallel one. In our 2D and 3D culture conditions, nonlinear cellular addition of the strains and strain avoidance concept reliably predicted the preferred cellular alignment. The 3D dECM-fibrin model system in this study shows that cyclical stretching supports cell survival and development. Using mechanical stimulation of pre-aligned heart cells, maturation markers are augmented in neonatal cardiomyocytes, while the beating culture period is prolonged, indicating an improved model function. We propose a simplified theoretical model based on numerical simulation and nonlinear strain avoidance by cells to explain oblique alignment angles. Thus, this work lays a possible rational basis for understanding and engineering oblique cellular alignments, such as the helicoidal layout of the heart, using approaches that simultaneously enhance maturation and function.
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Affiliation(s)
- Fatemeh Navaee
- Microsystems Laboratory-LMIS4, EPFL, 1015 Lausanne, Switzerland
- Department of Pathology and Immunology, Faculty of Medicine, CMU, 1206 Geneva, Switzerland
- Institute of Molecular Oncology and Stem Cell Biology, Ulm University Hospital, 89081 Ulm, Germany
| | - Philippe Renaud
- Microsystems Laboratory-LMIS4, EPFL, 1015 Lausanne, Switzerland
| | | | - Mathilde Durand
- Swiss Center for Electronics and Microtechnology (CSEM), 2002 Neuchatel, Switzerland
| | - Dara Zaman Bayat
- Swiss Center for Electronics and Microtechnology (CSEM), 2002 Neuchatel, Switzerland
| | - Diane Ledroit
- Swiss Center for Electronics and Microtechnology (CSEM), 2002 Neuchatel, Switzerland
| | - Sarah Heub
- Swiss Center for Electronics and Microtechnology (CSEM), 2002 Neuchatel, Switzerland
| | | | - Alexander Kleger
- Institute of Molecular Oncology and Stem Cell Biology, Ulm University Hospital, 89081 Ulm, Germany
- Interdisciplinary Pancreatology, Department of Internal Medicine 1, Ulm University Hospital, 89081 Ulm, Germany
- Organoid Core Facility, Medical Faculty, Ulm University Hospital, 89081 Ulm, Germany
| | - Thomas Braschler
- Department of Pathology and Immunology, Faculty of Medicine, CMU, 1206 Geneva, Switzerland
- Correspondence:
| | - Gilles Weder
- Swiss Center for Electronics and Microtechnology (CSEM), 2002 Neuchatel, Switzerland
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Pius-Sadowska E, Machaliński B. Pleiotropic activity of nerve growth factor in regulating cardiac functions and counteracting pathogenesis. ESC Heart Fail 2021; 8:974-987. [PMID: 33465292 PMCID: PMC8006610 DOI: 10.1002/ehf2.13138] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 11/05/2020] [Accepted: 11/11/2020] [Indexed: 12/30/2022] Open
Abstract
Cardiac innervation density generally reflects the levels of nerve growth factor (NGF) produced by the heart—changes in NGF expression within the heart and vasculature contribute to neuronal remodelling (e.g. sympathetic hyperinnervation or denervation). Its synthesis and release are altered under different pathological conditions. Although NGF is well known for its survival effects on neurons, it is clear that these effects are more wide ranging. Recent studies reported both in vitro and in vivo evidence for beneficial actions of NGF on cardiomyocytes in normal and pathological hearts, including prosurvival and antiapoptotic effects. NGF also plays an important role in the crosstalk between the nervous and cardiovascular systems. It was the first neurotrophin to be implicated in postnatal angiogenesis and vasculogenesis by autocrine and paracrine mechanisms. In connection with these unique cardiovascular properties of NGF, we have provided comprehensive insight into its function and potential effect of NGF underlying heart sustainable/failure conditions. This review aims to summarize the recent data on the effects of NGF on various cardiovascular neuronal and non‐neuronal functions. Understanding these mechanisms with respect to the diversity of NGF functions may be crucial for developing novel therapeutic strategies, including NGF action mechanism‐guided therapies.
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Affiliation(s)
- Ewa Pius-Sadowska
- Department of General Pathology, Pomeranian Medical University, Powstańców Wlkp. 72, Szczecin, 70111, Poland
| | - Bogusław Machaliński
- Department of General Pathology, Pomeranian Medical University, Powstańców Wlkp. 72, Szczecin, 70111, Poland
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Oh B, Swaminathan V, Malkovskiy A, Santhanam S, McConnell K, George PM. Single-Cell Encapsulation via Click-Chemistry Alters Production of Paracrine Factors from Neural Progenitor Cells. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:1902573. [PMID: 32328414 PMCID: PMC7175248 DOI: 10.1002/advs.201902573] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 01/27/2020] [Indexed: 05/05/2023]
Abstract
Extracellular matrix (ECM) properties affect multiple cellular processes such as cell survival, proliferation, and protein synthesis. Thus, a polymeric-cell delivery system with the ability to manipulate the extracellular environment can act as a fundamental regulator of cell function. Given the promise of stem cell therapeutics, a method to uniformly enhance stem cell function, in particular trophic factor release, can prove transformative in improving efficacy and increasing feasibility by reducing the total number of cells required. Herein, a click-chemistry powered 3D, single-cell encapsulation method aimed at synthesizing a polymeric coating with the optimal thickness around neural progenitor cells is introduced. Polymer encapsulation of neural stem cells significantly increases the release of neurotrophic factors such as VEGF and CNTF. Cell encapsulation with a soft extracellular polymer upregulates the ADCY8-cAMP pathway, suggesting a mechanism for the increase in paracrine factors. Hence, the described single-cell encapsulation technique can emerge as a translatable, nonviral cell modulation method and has the potential to improve stem cells' therapeutic effect.
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Affiliation(s)
- Byeongtaek Oh
- Department of Neurology and Neurological SciencesSchool of MedicineStanford UniversityStanfordCA94305USA
| | - Vishal Swaminathan
- Department of Neurology and Neurological SciencesSchool of MedicineStanford UniversityStanfordCA94305USA
| | - Andrey Malkovskiy
- Biomaterials and Advanced Drug Delivery LaboratorySchool of MedicineStanford UniversityStanfordCA94305USA
| | - Sruthi Santhanam
- Department of Neurology and Neurological SciencesSchool of MedicineStanford UniversityStanfordCA94305USA
| | - Kelly McConnell
- Department of Neurology and Neurological SciencesSchool of MedicineStanford UniversityStanfordCA94305USA
| | - Paul M. George
- Department of Neurology and Neurological SciencesSchool of MedicineStanford UniversityStanfordCA94305USA
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NGF-TrkA signaling in sensory nerves is required for skeletal adaptation to mechanical loads in mice. Proc Natl Acad Sci U S A 2017; 114:E3632-E3641. [PMID: 28416686 DOI: 10.1073/pnas.1701054114] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Sensory nerves emanating from the dorsal root extensively innervate the surfaces of mammalian bone, a privileged location for the regulation of biomechanical signaling. Here, we show that NGF-TrkA signaling in skeletal sensory nerves is an early response to mechanical loading of bone and is required to achieve maximal load-induced bone formation. First, the elimination of TrkA signaling in mice harboring mutant TrkAF592A alleles was found to greatly attenuate load-induced bone formation induced by axial forelimb compression. Next, both in vivo mechanical loading and in vitro mechanical stretch were shown to induce the profound up-regulation of NGF in osteoblasts within 1 h of loading. Furthermore, inhibition of TrkA signaling following axial forelimb compression was observed to reduce measures of Wnt/β-catenin activity in osteocytes in the loaded bone. Finally, the administration of exogenous NGF to wild-type mice was found to significantly increase load-induced bone formation and Wnt/β-catenin activity in osteocytes. In summary, these findings demonstrate that communication between osteoblasts and sensory nerves through NGF-TrkA signaling is essential for load-induced bone formation in mice.
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Zhang L, Han X, Cheng X, Tan XF, Zhao HY, Zhang XH. Denervated hippocampus provides a favorable microenvironment for neuronal differentiation of endogenous neural stem cells. Neural Regen Res 2016; 11:597-603. [PMID: 27212920 PMCID: PMC4870916 DOI: 10.4103/1673-5374.180744] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Fimbria-fornix transection induces both exogenous and endogenous neural stem cells to differentiate into neurons in the hippocampus. This indicates that the denervated hippocampus provides an environment for neuronal differentiation of neural stem cells. However, the pathways and mechanisms in this process are still unclear. Seven days after fimbria fornix transection, our reverse transcription polymerase chain reaction, western blot assay, and enzyme linked immunosorbent assay results show a significant increase in ciliary neurotrophic factor mRNA and protein expression in the denervated hippocampus. Moreover, neural stem cells derived from hippocampi of fetal (embryonic day 17) Sprague-Dawley rats were treated with ciliary neurotrophic factor for 7 days, with an increased number of microtubule associated protein-2-positive cells and decreased number of glial fibrillary acidic protein-positive cells detected. Our results show that ciliary neurotrophic factor expression is up-regulated in the denervated hippocampus, which may promote neuronal differentiation of neural stem cells in the denervated hippocampus.
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Affiliation(s)
- Lei Zhang
- Department of Human Anatomy, Institute of Neurobiology, Jiangsu Key Laboratory of Neuroregeneration, Medical School, Nantong University, Nantong, Jiangsu Province, China
| | - Xiao Han
- Department of Human Anatomy, Institute of Neurobiology, Jiangsu Key Laboratory of Neuroregeneration, Medical School, Nantong University, Nantong, Jiangsu Province, China
| | - Xiang Cheng
- Department of Human Anatomy, Institute of Neurobiology, Jiangsu Key Laboratory of Neuroregeneration, Medical School, Nantong University, Nantong, Jiangsu Province, China
| | - Xue-Feng Tan
- Department of Human Anatomy, Institute of Neurobiology, Jiangsu Key Laboratory of Neuroregeneration, Medical School, Nantong University, Nantong, Jiangsu Province, China
| | - He-Yan Zhao
- Department of Human Anatomy, Institute of Neurobiology, Jiangsu Key Laboratory of Neuroregeneration, Medical School, Nantong University, Nantong, Jiangsu Province, China
| | - Xin-Hua Zhang
- Department of Human Anatomy, Institute of Neurobiology, Jiangsu Key Laboratory of Neuroregeneration, Medical School, Nantong University, Nantong, Jiangsu Province, China
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Schievink WI, Nuño M, Rozen TD, Maya MM, Mamelak AN, Carmichael J, Bonert VS. Hyperprolactinemia due to spontaneous intracranial hypotension. J Neurosurg 2015; 122:1020-5. [DOI: 10.3171/2014.9.jns132687] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT
Spontaneous intracranial hypotension is an increasingly recognized cause of headaches. Pituitary enlargement and brain sagging are common findings on MRI in patients with this disorder. The authors therefore investigated pituitary function in patients with spontaneous intracranial hypotension.
METHODS
Pituitary hormones were measured in a group of 42 consecutive patients with spontaneous intracranial hypotension. For patients with hyperprolactinemia, prolactin levels also were measured following treatment. Magnetic resonance imaging was performed prior to and following treatment.
RESULTS
The study group consisted of 27 women and 15 men with a mean age at onset of symptoms of 52.2 ± 10.7 years (mean ± SD; range 17–72 years). Hyperprolactinemia was detected in 10 patients (24%), ranging from 16 ng/ml to 96.6 ng/ml in men (normal range 3–14.7 ng/ml) and from 31.3 ng/ml to 102.5 ng/ml in women (normal range 3.8–23.2 ng/ml). In a multivariate analysis, only brain sagging on MRI was associated with hyperprolactinemia. Brain sagging was present in 60% of patients with hyperprolactinemia and in 19% of patients with normal prolactin levels (p = 0.02). Following successful treatment of the spontaneous intracranial hypotension, hyperprolactinemia resolved, along with normalization of brain MRI findings in all 10 patients.
CONCLUSIONS
Spontaneous intracranial hypotension is a previously undescribed cause of hyperprolactinemia. Brain sagging causing distortion of the pituitary stalk (stalk effect) may be responsible for the hyperprolactinemia.
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Affiliation(s)
| | | | - Todd D. Rozen
- 2Department of Neurology, Geisinger Wyoming Valley Medical Center, Wilkes-Barre, Pennsylvania
| | | | | | - John Carmichael
- 4Pituitary Center, Cedars-Sinai Medical Center, Los Angeles, California; and
| | - Vivien S. Bonert
- 4Pituitary Center, Cedars-Sinai Medical Center, Los Angeles, California; and
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Fink DM, Connor AL, Kelley PM, Steele MM, Hollingsworth MA, Tempero RM. Nerve growth factor regulates neurolymphatic remodeling during corneal inflammation and resolution. PLoS One 2014; 9:e112737. [PMID: 25383879 PMCID: PMC4226611 DOI: 10.1371/journal.pone.0112737] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 10/14/2014] [Indexed: 11/19/2022] Open
Abstract
The cellular and physiologic mechanisms that regulate the resolution of inflammation remain poorly defined despite their widespread importance in improving inflammatory disease outcomes. We studied the resolution of two cardinal signs of inflammation–pain and swelling–by investigating molecular mechanisms that regulate neural and lymphatic vessel remodeling during the resolution of corneal inflammation. A mouse model of corneal inflammation and wound recovery was developed to study this process in vivo. Administration of nerve growth factor (NGF) increased pain sensation and inhibited neural remodeling and lymphatic vessel regression processes during wound recovery. A complementary in vivo approach, the corneal micropocket assay, revealed that NGF-laden pellets stimulated lymphangiogenesis and increased protein levels of VEGF-C. Adult human dermal lymphatic endothelial cells did not express canonical NGF receptors TrkA and p75NTR or activate downstream MAPK- or Akt-pathway effectors in the presence of NGF, although NGF treatment increased their migratory and tubulogenesis capacities in vitro. Blockade of the VEGF-R2/R3 signaling pathway ablated NGF-mediated lymphangiogenesis in vivo. These findings suggest a hierarchical relationship with NGF functioning upstream of the VEGF family members, particularly VEGF-C, to stimulate lymphangiogenesis. Taken together, these studies show that NGF stimulates lymphangiogenesis and that NGF may act as a pathogenic factor that negatively regulates the normal neural and lymphatic vascular remodeling events that accompany wound recovery.
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Affiliation(s)
- Darci M. Fink
- University of Nebraska Medical Center, Eppley Institute for Research in Cancer and Allied Diseases, 985950 Nebraska Medical Center, Omaha, Nebraska 68198-5950, United States of America
| | - Alicia L. Connor
- Boys Town National Research Hospital, Department of Genetics, 555 North 30 Street, Omaha, Nebraska 68131, United States of America
| | - Philip M. Kelley
- Boys Town National Research Hospital, Department of Genetics, 555 North 30 Street, Omaha, Nebraska 68131, United States of America
| | - Maria M. Steele
- University of Nebraska Medical Center, Eppley Institute for Research in Cancer and Allied Diseases, 985950 Nebraska Medical Center, Omaha, Nebraska 68198-5950, United States of America
| | - Michael A. Hollingsworth
- University of Nebraska Medical Center, Eppley Institute for Research in Cancer and Allied Diseases, 985950 Nebraska Medical Center, Omaha, Nebraska 68198-5950, United States of America
| | - Richard M. Tempero
- Boys Town National Research Hospital, Department of Genetics, 555 North 30 Street, Omaha, Nebraska 68131, United States of America
- Boys Town National Research Hospital, Department of Otolaryngology, 555 North 30 Street, Omaha, Nebraska 68131, United States of America
- * E-mail:
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8
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Yuan Q, Li JJ, An CH, Sun L. Biological characteristics of rat dorsal root ganglion cell and human vascular endothelial cell in mono- and co-culture. Mol Biol Rep 2014; 41:6949-56. [PMID: 25028268 DOI: 10.1007/s11033-014-3581-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 07/01/2014] [Indexed: 11/29/2022]
Abstract
This study aimed to evaluate the biological activity of rat dorsal root ganglion cell (DRGC) and human vascular endothelial cell (HMVEC) in mono- and co-culture. Expression levels of vascular endothelial growth factor (VEGF) and nerve growth factor (NGF) mRNA were measured by quantitative real-time RT-PCR (qRT-PCR). Western blot analysis was used to identify VEGF and NGF protein expressions. Cell injury was assessed by measuring cell viability with methylthiazol tetrazolium (MTT) assay. The results showed that VEGF and NGF mRNA levels in the HMVEC+DRGC group were significantly higher than those in the DRGC and HMVEC groups (all p < 0.05). There were also greater increases in both VEGF and NGF protein expressions in the HMVEC+DRGC group than those in the DRGC and HMVEC groups (all p < 0.05). The results of MTT analysis revealed significant differences in cell viability among the HMVEC+DRGC group and the DRGC and HMVEC groups (all p < 0.05). In summary, our findings provide evidence that DRGC and HMVEC in co-culture may exhibit greater biological activity than DRGC in mono-culture.
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Affiliation(s)
- Quan Yuan
- Department of Orthopedics, Shengjing Hospital, China Medical University, San Hao Street No. 36, Heping District, Shenyang, 110004, People's Republic of China,
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Liu H, Tang L. Mechano-regulation of alternative splicing. Curr Genomics 2013; 14:49-55. [PMID: 23997650 PMCID: PMC3580779 DOI: 10.2174/138920213804999156] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Revised: 11/22/2012] [Accepted: 12/23/2012] [Indexed: 01/29/2023] Open
Abstract
Alternative splicing contributes to the complexity of proteome by producing multiple mRNAs from a single gene. Affymetrix exon arrays and experiments in vivo or in vitro demonstrated that alternative splicing was regulated by mechanical stress. Expression of mechano-growth factor (MGF) which is the splicing isoform of insulin-like growth factor 1(IGF-1) and vascular endothelial growth factor (VEGF) splicing variants such as VEGF121, VEGF165, VEGF206, VEGF189, VEGF165 and VEGF145 are regulated by mechanical stress. However, the mechanism of this process is not yet clear. Increasing evidences showed that the possible mechanism is related to Ca2+ signal pathway and phosphorylation signal pathway. This review proposes possible mechanisms of mechanical splicing regulation. This will contribute to the biomechanical study of alternative splicing.
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Affiliation(s)
- Huan Liu
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044, China
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Carmeliet P, Ruiz de Almodovar C, Carmen RDA. VEGF ligands and receptors: implications in neurodevelopment and neurodegeneration. Cell Mol Life Sci 2013; 70:1763-78. [PMID: 23475071 PMCID: PMC11113464 DOI: 10.1007/s00018-013-1283-7] [Citation(s) in RCA: 124] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 01/28/2013] [Accepted: 01/28/2013] [Indexed: 12/15/2022]
Abstract
Intensive research in the last decade shows that the prototypic angiogenic factor vascular endothelial growth factor (VEGF) can have direct effects in neurons and modulate processes such as neuronal migration, axon outgrowth, axon guidance and neuronal survival. Depending on the neuronal cell type and the process, VEGF seems to exert these effects by signaling via different receptors. It is also becoming clear that other VEGF ligands such as VEGF-B, -C and -D can act in various neuronal cell types as well. Moreover, apart from playing a role in physiological conditions, VEGF and VEGF-B have been related to different neurological disorders. We give an update on how VEGF controls different processes during neurodevelopment as well as on its role in several neurodegenerative disorders. We also discuss recent findings demonstrating that other VEGF ligands influence processes such as neurogenesis and dendrite arborization and participate in neurodegeneration.
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Affiliation(s)
- Peter Carmeliet
- Laboratory of Angiogenesis and Neurovascular Link, Vesalius Research Center, K.U.Leuven, 3000, Leuven, Belgium.
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11
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Abstract
Many secreted polypeptide regulators of angiogenesis are devoid of signal peptides. These proteins are released through nonclassical pathways independent of endoplasmic reticulum and Golgi. In most cases, the nonclassical protein export is induced by stress. It usually serves to stimulate repair or inflammation in damaged tissues. We review the secreted signal peptide-less regulators of angiogenesis and discuss the mechanisms and biological significance of their unconventional export.
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Affiliation(s)
- Igor Prudovsky
- Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074, USA
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12
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Malykhina AP, Lei Q, Erickson CS, Epstein ML, Saban MR, Davis CA, Saban R. VEGF induces sensory and motor peripheral plasticity, alters bladder function, and promotes visceral sensitivity. BMC PHYSIOLOGY 2012; 12:15. [PMID: 23249422 PMCID: PMC3543727 DOI: 10.1186/1472-6793-12-15] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 12/11/2012] [Indexed: 12/30/2022]
Abstract
BACKGROUND This work tests the hypothesis that bladder instillation with vascular endothelial growth factor (VEGF) modulates sensory and motor nerve plasticity, and, consequently, bladder function and visceral sensitivity.In addition to C57BL/6J, ChAT-cre mice were used for visualization of bladder cholinergic nerves. The direct effect of VEGF on the density of sensory nerves expressing the transient receptor potential vanilloid subfamily 1 (TRPV1) and cholinergic nerves (ChAT) was studied one week after one or two intravesical instillations of the growth factor.To study the effects of VEGF on bladder function, mice were intravesically instilled with VEGF and urodynamic evaluation was assessed. VEGF-induced alteration in bladder dorsal root ganglion (DRG) neurons was performed on retrogradly labeled urinary bladder afferents by patch-clamp recording of voltage gated Na+ currents. Determination of VEGF-induced changes in sensitivity to abdominal mechanostimulation was performed by application of von Frey filaments. RESULTS In addition to an overwhelming increase in TRPV1 immunoreactivity, VEGF instillation resulted in an increase in ChAT-directed expression of a fluorescent protein in several layers of the urinary bladder. Intravesical VEGF caused a profound change in the function of the urinary bladder: acute VEGF (1 week post VEGF treatment) reduced micturition pressure and longer treatment (2 weeks post-VEGF instillation) caused a substantial reduction in inter-micturition interval. In addition, intravesical VEGF resulted in an up-regulation of voltage gated Na(+) channels (VGSC) in bladder DRG neurons and enhanced abdominal sensitivity to mechanical stimulation. CONCLUSIONS For the first time, evidence is presented indicating that VEGF instillation into the mouse bladder promotes a significant increase in peripheral nerve density together with alterations in bladder function and visceral sensitivity. The VEGF pathway is being proposed as a key modulator of neural plasticity in the pelvis and enhanced VEGF content may be associated with visceral hyperalgesia, abdominal discomfort, and/or pelvic pain.
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Affiliation(s)
- Anna P Malykhina
- Department of Surgery, Division of Urology, University of Pennsylvania School of Medicine, Glenolden, 19036-2307, USA
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Gulati P, Muthuraman A, Jaggi AS, Singh N. Neuroprotective effect of gadolinium: a stretch-activated calcium channel blocker in mouse model of ischemia-reperfusion injury. Naunyn Schmiedebergs Arch Pharmacol 2012; 386:255-64. [PMID: 23229582 DOI: 10.1007/s00210-012-0819-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 11/27/2012] [Indexed: 12/17/2022]
Abstract
The present study was designed to investigate the potential of gadolinium, a stretch-activated calcium channel blocker in ischemic reperfusion (I/R)-induced brain injury in mice. Bilateral carotid artery occlusion of 12 min followed by reperfusion for 24 h was given to induce cerebral injury in male Swiss mice. Cerebral infarct size was measured using triphenyltetrazolium chloride staining. Memory was assessed using Morris water maze test and motor incoordination was evaluated using rota-rod, lateral push, and inclined beam walking tests. In addition, total calcium, thiobarbituric acid reactive substance (TBARS), reduced glutathione (GSH), and acetylcholinesterase (AChE) activity were also estimated in brain tissue. I/R injury produced a significant increase in cerebral infarct size. A significant loss of memory along with impairment of motor performance was also noted. Furthermore, I/R injury also produced a significant increase in levels of TBARS, total calcium, AChE activity, and a decrease in GSH levels. Pretreatment of gadolinium significantly attenuated I/R-induced infarct size, behavioral and biochemical changes. On the basis of the present findings, we can suggest that opening of stretch-activated calcium channel may play a critical role in ischemic reperfusion-induced brain injury and that gadolinium has neuroprotective potential in I/R-induced injury.
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Affiliation(s)
- Puja Gulati
- Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala, 147002, Punjab, India
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