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Ergul Erkec O, Huyut Z, Acikgoz E, Huyut MT. Effects of exogenous ghrelin treatment on oxidative stress, inflammation and histological parameters in a fat-fed streptozotocin rat model. Arch Physiol Biochem 2024:1-11. [PMID: 39324977 DOI: 10.1080/13813455.2024.2407551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 07/17/2024] [Accepted: 09/16/2024] [Indexed: 09/27/2024]
Abstract
In this study, the anti-inflammatory, antioxidative, and protective effects of ghrelin were investigated in a fat-fed streptozotocin (STZ) rat model and compared with metformin, diabetes and the healthy control groups. Histopathological evaluations were performed on H&E-stained pancreas and brain sections. Biochemical parameters were investigated by enzyme-linked immunosorbent assay. Blood glucose levels were significantly decreased with ghrelin or metformin treatments than the diabetes group. STZ administration increased brain, renal and pancreatic IL-1β, TNF-α and MDA while decreasing GPX, CAT, SOD, and NGF levels. Ghrelin increased renal GPX, CAT, NGF pancreatic GPX, SOD, CAT, NGF and brain SOD, NGF while it decreased renal, pancreatic and brain IL-1β, TNF-α and MDA levels. Ghrelin reduced neuronal loss and degeneration in the cerebral cortex and hippocampus and greatly ameliorated diabetes-related damage in pancreas. In conclusion, the data suggested that ghrelin is an effective candidate as a protectant for reducing the adverse effects of diabetes.
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Affiliation(s)
- Ozlem Ergul Erkec
- Department of Physiology, Faculty of Medicine, Van Yuzuncu Yil University, Van, Turkey
| | - Zubeyir Huyut
- Department of Biochemistry, Faculty of Medicine, Van Yuzuncu Yil University, Van, Turkey
| | - Eda Acikgoz
- Department of Histology and Embryology, Faculty of Medicine, Van Yuzuncu Yil University, Van, Turkey
| | - Mehmet Tahir Huyut
- Department of Biostatistics, Faculty of Medicine, Erzincan Binali Yıldırım University, Erzincan, Turkey
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2
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Frey CB, Park R, Robinson R, Yoder C. Nagging Pain and Foot Ulcers Can be Treated into Remission. Endocrinol Metab Clin North Am 2023; 52:119-133. [PMID: 36754488 DOI: 10.1016/j.ecl.2022.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Lower extremity ulcerations are very common in patients with diabetes. These wounds lead to amputation in a surprisingly large percentage of patients with diabetes. The mortality rate following amputation in a patient with diabetes is alarmingly high. Preventive treatment is pivotal to avoid the numerous complications associated with diabetic ulcerations. However, at the onset of ulceration, early treatment under the supervision and guidance of a specialist can result in remission. Diabetic peripheral neuropathy is also a life-altering and debilitating disease. Although some patients experience numbness, some experience pain that can be sharp, shooting, and tingling. Although treatment is challenging and often requires medication, newer modalities, such as stimulation and physical therapy, have shown promise in reversing the devastating effects of peripheral neuropathy.
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Affiliation(s)
- Craig B Frey
- University Hospitals Podiatric Medicine and Surgery, University Hospitals Advanced Limb Salvage and Reconstruction, 11100 Euclid Avenue, Cleveland, OH 44106, USA.
| | - Richard Park
- University Hospitals Podiatric Medicine and Surgery, 11100 Euclid Avenue, Cleveland, OH 44106, USA
| | - Rachel Robinson
- University Hospitals Podiatric Medicine and Surgery, 11100 Euclid Avenue, Cleveland, OH 44106, USA
| | - Courtney Yoder
- University Hospitals Podiatric Medicine and Surgery, 11100 Euclid Avenue, Cleveland, OH 44106, USA
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3
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Alkharfy KM, Ahmad A, Siddiquei MM, Ghulam M, El-Asrar AA. Thymoquinone Attenuates Retinal Expression of Mediators and Markers of Neurodegeneration in a Diabetic Animal Model. Curr Mol Pharmacol 2023; 16:188-196. [PMID: 35049444 DOI: 10.2174/1874467215666220113105300] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/07/2021] [Accepted: 10/21/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Diabetic retinopathy (DR) is a slow eye disease that affects the retina due to a long-standing uncontrolled diabetes mellitus. Hyperglycemia-induced oxidative stress can lead to neuronal damage leading to DR. OBJECTIVE The aim of the current investigation is to assess the protective effects of thymoquinone (TQ) as a potential compound for the treatment and/or prevention of neurovascular complications of diabetes, including DR. METHODS Diabetes was induced in rats by the administration of streptozotocin (55 mg/kg intraperitoneally, i.p.). Subsequently, diabetic rats were treated with either TQ (2 mg/kg i.p.) or vehicle on alternate days for three weeks. A healthy control group was also run in parallel. At the end of the treatment period, animals were euthanized, and the retinas were collected and analyzed for the expression levels of brain-derived neurotrophic factor (BDNF), tyrosine hydroxylase (TH), nerve growth factor receptor (NGFR), and caspase-3 using Western blotting techniques in the retina of diabetic rats and compared with the normal control rats. In addition, dichlorofluorescein (DCF) levels in the retina were assessed as a marker of reactive oxygen species (ROS), and blood-retinal barrier breakdown (BRB) was examined for vascular permeability. The systemic effects of TQ treatments on glycemic control, kidney and liver functions were also assessed in all groups. RESULTS Diabetic animals treated with TQ showed improvements in the liver and kidney functions compared with control diabetic rats. Normalization in the levels of neuroprotective factors, including BDNF, TH, and NGFR, was observed in the retina of diabetic rats treated with TQ. In addition, TQ ameliorated the levels of apoptosis regulatory protein caspase-3 in the retina of diabetic rats and reduced disruption of the blood-retinal barrier, possibly through a reduction in reactive oxygen species (ROS) generation. CONCLUSION These findings suggest that TQ harbors a significant potential to limit the neurodegeneration and retinal damage that can be provoked by hyperglycemia in vivo.
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Affiliation(s)
- Khalid M Alkharfy
- Department of Clinical Pharmacy, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Ajaz Ahmad
- Department of Clinical Pharmacy, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Mohammad Mairaj Siddiquei
- Department of Ophthalmology, College of Medicine, King Abdul Aziz Hospital, King Saud University, Riyadh 11451, Saudi Arabia
| | - Mohammad Ghulam
- Department of Ophthalmology, College of Medicine, King Abdul Aziz Hospital, King Saud University, Riyadh 11451, Saudi Arabia
| | - Ahmed Abu El-Asrar
- Department of Ophthalmology, College of Medicine, King Abdul Aziz Hospital, King Saud University, Riyadh 11451, Saudi Arabia
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Genetic and Epigenomic Modifiers of Diabetic Neuropathy. Int J Mol Sci 2021; 22:ijms22094887. [PMID: 34063061 PMCID: PMC8124699 DOI: 10.3390/ijms22094887] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 04/29/2021] [Accepted: 05/03/2021] [Indexed: 12/18/2022] Open
Abstract
Diabetic neuropathy (DN), the most common chronic and progressive complication of diabetes mellitus (DM), strongly affects patients’ quality of life. DN could be present as peripheral, autonomous or, clinically also relevant, uremic neuropathy. The etiopathogenesis of DN is multifactorial, and genetic components play a role both in its occurrence and clinical course. A number of gene polymorphisms in candidate genes have been assessed as susceptibility factors for DN, and most of them are linked to mechanisms such as reactive oxygen species production, neurovascular impairments and modified protein glycosylation, as well as immunomodulation and inflammation. Different epigenomic mechanisms such as DNA methylation, histone modifications and non-coding RNA action have been studied in DN, which also underline the importance of “metabolic memory” in DN appearance and progression. In this review, we summarize most of the relevant data in the field of genetics and epigenomics of DN, hoping they will become significant for diagnosis, therapy and prevention of DN.
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Lee KA, Park TS, Jin HY. Non-glucose risk factors in the pathogenesis of diabetic peripheral neuropathy. Endocrine 2020; 70:465-478. [PMID: 32895875 DOI: 10.1007/s12020-020-02473-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 08/23/2020] [Indexed: 11/29/2022]
Abstract
In this review, we consider the diverse risk factors in diabetes patients beyond hyperglycemia that are being recognized as contributors to diabetic peripheral neuropathy (DPN). Interest in such alternative mechanisms has been encouraged by the recognition that neuropathy occurs in subjects with metabolic syndrome and pre-diabetes and by the reporting of several large clinical studies that failed to show reduced prevalence of neuropathy after intensive glucose control in patients with type 2 diabetes. Animal models of obesity, dyslipidemia, hypertension, and other disorders common to both pre-diabetes and diabetes have been used to highlight a number of plausible pathogenic mechanisms that may either damage the nerve independent of hyperglycemia or augment the toxic potential of hyperglycemia. While pathogenic mechanisms stemming from hyperglycemia are likely to be significant contributors to DPN, future therapeutic strategies will require a more nuanced approach that considers a range of concurrent insults derived from the complex pathophysiology of diabetes beyond direct hyperglycemia.
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Affiliation(s)
- Kyung Ae Lee
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Research Institute of Clinical Medicine of Jeonbuk National University-Jeonbuk National University Hospital, Jeonbuk National University, Medical School, Jeonju, South Korea
| | - Tae Sun Park
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Research Institute of Clinical Medicine of Jeonbuk National University-Jeonbuk National University Hospital, Jeonbuk National University, Medical School, Jeonju, South Korea
| | - Heung Yong Jin
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Research Institute of Clinical Medicine of Jeonbuk National University-Jeonbuk National University Hospital, Jeonbuk National University, Medical School, Jeonju, South Korea.
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6
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Gonçalves NP, Yan Y, Ulrichsen M, Venø MT, Poulsen ET, Enghild JJ, Kjems J, Vægter CB. Modulation of Small RNA Signatures in Schwann-Cell-Derived Extracellular Vesicles by the p75 Neurotrophin Receptor and Sortilin. Biomedicines 2020; 8:E450. [PMID: 33114403 PMCID: PMC7694014 DOI: 10.3390/biomedicines8110450] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/20/2020] [Accepted: 10/22/2020] [Indexed: 12/12/2022] Open
Abstract
Schwann cells (SCs) are the main glial cells of the peripheral nervous system (PNS) and are known to be involved in various pathophysiological processes, such as diabetic neuropathy and nerve regeneration, through neurotrophin signaling. Such glial trophic support to axons, as well as neuronal survival/death signaling, has previously been linked to the p75 neurotrophin receptor (p75NTR) and its co-receptor Sortilin. Recently, SC-derived extracellular vesicles (EVs) were shown to be important for axon growth and nerve regeneration, but cargo of these glial cell-derived EVs has not yet been well-characterized. In this study, we aimed to characterize signatures of small RNAs in EVs derived from wild-type (WT) SCs and define differentially expressed small RNAs in EVs derived from SCs with genetic deletions of p75NTR (Ngfr-/-) or Sortilin (Sort1-/-). Using RNA sequencing, we identified a total of 366 miRNAs in EVs derived from WT SCs of which the most highly expressed are linked to the regulation of axonogenesis, axon guidance and axon extension, suggesting an involvement of SC EVs in axonal homeostasis. Signaling of SC EVs to non-neuronal cells was also suggested by the presence of several miRNAs important for regulation of the endothelial cell apoptotic process. Ablated p75NTR or sortilin expression in SCs translated into a set of differentially regulated tRNAs and miRNAs, with impact in autophagy and several cellular signaling pathways such as the phosphatidylinositol signaling system. With this work, we identified the global expression profile of small RNAs present in SC-derived EVs and provided evidence for a regulatory function of these vesicles on the homeostasis of other cell types of the PNS. Differentially identified miRNAs can pave the way to a better understanding of p75NTR and sortilin roles regarding PNS homeostasis and disease.
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Affiliation(s)
- Nádia P. Gonçalves
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic-EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark; (M.U.); (C.B.V.)
| | - Yan Yan
- Interdisciplinary Nanoscience Centre (iNANO), Aarhus University, 8000 Aarhus, Denmark; (Y.Y.); (M.T.V.); (J.K.)
- Omiics ApS, 8000 Aarhus, Denmark
| | - Maj Ulrichsen
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic-EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark; (M.U.); (C.B.V.)
| | - Morten T. Venø
- Interdisciplinary Nanoscience Centre (iNANO), Aarhus University, 8000 Aarhus, Denmark; (Y.Y.); (M.T.V.); (J.K.)
- Omiics ApS, 8000 Aarhus, Denmark
| | - Ebbe T. Poulsen
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark; (E.T.P.); (J.J.E.)
| | - Jan J. Enghild
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark; (E.T.P.); (J.J.E.)
| | - Jørgen Kjems
- Interdisciplinary Nanoscience Centre (iNANO), Aarhus University, 8000 Aarhus, Denmark; (Y.Y.); (M.T.V.); (J.K.)
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark; (E.T.P.); (J.J.E.)
| | - Christian B. Vægter
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic-EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark; (M.U.); (C.B.V.)
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Kalwat MA, Huang Z, Binns DD, McGlynn K, Cobb MH. α 2-Adrenergic Disruption of β Cell BDNF-TrkB Receptor Tyrosine Kinase Signaling. Front Cell Dev Biol 2020; 8:576396. [PMID: 33178692 PMCID: PMC7593622 DOI: 10.3389/fcell.2020.576396] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 09/14/2020] [Indexed: 12/11/2022] Open
Abstract
Adrenergic signaling is a well-known input into pancreatic islet function. Specifically, the insulin-secreting islet β cell expresses the Gi/o-linked α2-adrenergic receptor, which upon activation suppresses insulin secretion. The use of the adrenergic agonist epinephrine at micromolar doses may have supraphysiological effects. We found that pretreating β cells with micromolar concentrations of epinephrine differentially inhibited activation of receptor tyrosine kinases. We chose TrkB as an example because of its relative sensitivity to the effects of epinephrine and due to its potential regulatory role in the β cell. Our characterization of brain-derived neurotrophic factor (BDNF)-TrkB signaling in MIN6 β cells showed that TrkB is activated by BDNF as expected, leading to canonical TrkB autophosphorylation and subsequent downstream signaling, as well as chronic effects on β cell growth. Micromolar, but not nanomolar, concentrations of epinephrine blocked BDNF-induced TrkB autophosphorylation and downstream mitogen-activated protein kinase pathway activation, suggesting an inhibitory phenomenon at the receptor level. We determined epinephrine-mediated inhibition of TrkB activation to be Gi/o-dependent using pertussis toxin, arguing against an off-target effect of high-dose epinephrine. Published data suggested that inhibition of potassium channels or phosphoinositide-3-kinase signaling may abrogate the negative effects of epinephrine; however, these did not rescue TrkB signaling in our experiments. Taken together, these results show that (1) TrkB kinase signaling occurs in β cells and (2) use of epinephrine in studies of insulin secretion requires careful consideration of concentration-dependent effects. BDNF-TrkB signaling in β cells may underlie pro-survival or growth signaling and warrants further study.
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Affiliation(s)
- Michael A. Kalwat
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, United States
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8
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Kiyanpour F, Abedi M, Gheisari Y. A systematic integrative approach reveals novel microRNAs in diabetic nephropathy. JOURNAL OF RESEARCH IN MEDICAL SCIENCES 2020; 25:1. [PMID: 32055241 PMCID: PMC7003547 DOI: 10.4103/jrms.jrms_289_19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Revised: 06/19/2019] [Accepted: 09/08/2019] [Indexed: 12/22/2022]
Abstract
Background: Despite huge efforts, the underlying molecular mechanisms of diabetic nephropathy (DN) are yet elusive, and holistic views have rarely been generated. Considering the complexity of DN pathogenesis, the integration of datasets from different molecular types to construct a multilayer map of DN can provide a comprehensive insight toward the disease mechanisms and also can generate new knowledge. Here, we have re-analyzed two mRNA microarray datasets related to glomerular and tubulointerstitial compartments of human diabetic kidneys. Materials and Methods: The quality of the datasets was confirmed by unsupervised hierarchical clustering and principal component analysis. For each dataset, differentially expressed (DE) genes were identified, and transcription factors (TFs) regulating these genes and kinases phosphorylating the TFs were enriched. Furthermore, microRNAs (miRNAs) targeting the DE genes, TFs, and kinases were detected. Based on the harvested genes for glomeruli and tubulointerstitium, key signaling pathways and biological processes involved in diseases pathogenesis were recognized. In addition, the interaction of different elements in each kidney compartment was depicted in multilayer networks, and topology analysis was performed to identify key nodes. Central miRNAs whose target genes were most likely to be related to DN were selected, and their expressions were quantitatively measured in a streptozotocin-induced DN mouse model. Results: Among the examined miRNAs, miR-208a-3p and miR-496a-3p are, for the first time, found to be significantly overexpressed in the cortex of diabetic kidneys compared to controls. Conclusion: We predict that miR-208 is involved in oxygen metabolism and regulation of cellular energy balance. Furthermore, miR-496 potentially regulates protein metabolism and ion transport. However, their exact functions remain to be investigated in future studies. Taken together, starting from transcriptomics data, we have generated multilayer interaction networks and introduced novel players in DN.
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Affiliation(s)
- Farnoush Kiyanpour
- Department of Genetics and Molecular Biology, Isfahan University of Medical Sciences, Isfahan, Iran.,Student Research Committee, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Maryam Abedi
- Department of Genetics and Molecular Biology, Isfahan University of Medical Sciences, Isfahan, Iran.,Regenerative Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Yousof Gheisari
- Department of Genetics and Molecular Biology, Isfahan University of Medical Sciences, Isfahan, Iran.,Regenerative Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
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Ziegler D, Strom A, Bönhof GJ, Kannenberg JM, Heier M, Rathmann W, Peters A, Meisinger C, Roden M, Thorand B, Herder C. Deficits in systemic biomarkers of neuroinflammation and growth factors promoting nerve regeneration in patients with type 2 diabetes and polyneuropathy. BMJ Open Diabetes Res Care 2019; 7:e000752. [PMID: 31803481 PMCID: PMC6887496 DOI: 10.1136/bmjdrc-2019-000752] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 11/04/2019] [Accepted: 11/06/2019] [Indexed: 12/14/2022] Open
Abstract
INTRODUCTION The determinants and mechanisms contributing to diabetic sensorimotor polyneuropathy (DSPN) remain unclear. Since neuroinflammation and altered nerve regeneration have been implicated in the pathogenesis of both DSPN and neuropathic pain, we hypothesized that the corresponding biomarkers could be associated with DSPN in general and could have the potential to discriminate between the painful and painless DSPN entities. METHODS In a cross-sectional study using multimarker proximity extension assay technology we assessed 71 serum biomarkers including cytokines, chemokines, growth factors, receptors, and others in patients with type 2 diabetes with DSPN (DSPN+) (n=304) or without DSPN (DSPN-) (n=158) and persons with normal glucose tolerance (NGT) without polyneuropathy (n=354). RESULTS After adjustment for multiple testing and sex, age, body mass index, HbA1c, and smoking, the serum levels of 17 biomarkers (four cytokines, five chemokines, four growth factors, two receptors, two miscellaneous) were lower in DSPN+ than in DSPN- and NGT. In DSPN+, six of these biomarkers were associated with peripheral nerve function. The concentrations of 15 other biomarkers differed between NGT and both DSPN+ and DSPN-, but not between DSPN+ and DSPN-. No differences in biomarker levels were found between patients with painful (n=164) and painless DSPN (n=140). CONCLUSIONS Deficits in systemic cytokines, chemokines, and growth factors promoting nerve regeneration in patients with type 2 diabetes are linked to polyneuropathy in general but not specifically to the painful or painless entity. TRIAL REGISTRATION NUMBER NCT02243475.
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Affiliation(s)
- Dan Ziegler
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Alexander Strom
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Gidon J Bönhof
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Julia M Kannenberg
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Margit Heier
- Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Wolfgang Rathmann
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
- Institute for Biometrics and Epidemiology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Annette Peters
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
- Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Christina Meisinger
- Independent Research Group Clinical Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- Chair of Epidemiology, Ludwig-Maximilians-Universität München am UNIKA-T Augsburg, Augsburg, Germany
| | - Michael Roden
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Barbara Thorand
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
- Institute of Epidemiology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Christian Herder
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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Aarão TLDS, de Sousa JR, Falcão ASC, Falcão LFM, Quaresma JAS. Nerve Growth Factor and Pathogenesis of Leprosy: Review and Update. Front Immunol 2018; 9:939. [PMID: 29867937 PMCID: PMC5949531 DOI: 10.3389/fimmu.2018.00939] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 04/16/2018] [Indexed: 12/11/2022] Open
Abstract
Neurotrophins are a family of proteins that regulate different aspects of biological development and neural function and are of great importance in neuroplasticity. This group of proteins has multiple functions in neuronal cells, as well as in other cellular populations. Nerve growth factor (NGF) is a neurotrophin that is endogenously produced during development and maturation by multiple cell types, including neurons, Schwann cells, oligodendrocytes, lymphocytes, mast cells, macrophages, keratinocytes, and fibroblasts. These cells produce proNGF, which is transformed by proteolytic cleavage into the biologically active NGF in the endoplasmic reticulum. The present review describes the role of NGF in the pathogenesis of leprosy and its correlations with different clinical forms of the disease and with the phenomena of regeneration and neural injury observed during infection. We discuss the involvement of NGF in the induction of neural damage and the pathophysiology of pain associated with peripheral neuropathy in leprosy. We also discuss the roles of immune factors in the evolution of this pathological process. Finally, we highlight avenues of investigation for future research to broaden our understanding of the role of NGF in the pathogenesis of leprosy. Our analysis of the literature indicates that NGF plays an important role in the evolution and outcome of Mycobacterium leprae infection. The findings described here highlight an important area of investigation, as leprosy is one of the main causes of infection in the peripheral nervous system.
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Affiliation(s)
| | | | | | | | - Juarez Antônio Simões Quaresma
- Center of Health and Biological Sciences, State University of Para, Belem, Brazil.,Tropical Medicine Center, Federal University of Para, Belem, Brazil.,Evandro Chagas Institute, Ministry of Health, Ananindeua, Brazil
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11
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Saudek F, Cahová M, Havrdová T, Zacharovová K, Daňková H, Voska L, Lánská V, Üçeyler N, Sommer C. Preserved Expression of Skin Neurotrophic Factors in Advanced Diabetic Neuropathy Does Not Lead to Neural Regeneration despite Pancreas and Kidney Transplantation. J Diabetes Res 2018; 2018:2309108. [PMID: 30648113 PMCID: PMC6311823 DOI: 10.1155/2018/2309108] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 09/27/2018] [Indexed: 01/11/2023] Open
Abstract
Diabetic peripheral neuropathy (DPN) is a common complication of diabetes with potential severe consequences. Its pathogenesis involves hyperglycemia-linked mechanisms, which may include changes in the expression of neurotrophic growth factors. We analyzed the expression of 29 factors potentially related to nerve degeneration and regeneration in skin biopsies from 13 type 1 diabetic pancreas and kidney recipients with severe DPN including severe depletion of intraepidermal nerve fibers (IENF) in lower limb skin biopsies (group Tx1 1st examination). The investigation was repeated after a median 28-month period of normoglycemia achieved by pancreas transplantation (group Tx1 2nd examination). The same tests were performed in 13 stable normoglycemic pancreas and kidney recipients 6-12 years posttransplantation (group Tx2), in 12 matched healthy controls (group HC), and in 12 type 1 diabetic subjects without severe DPN (group DM). Compared to DM and HC groups, we found a significantly higher (p < 0.05-0.001) expression of NGF (nerve growth factor), NGFR (NGF receptor), NTRK1 (neurotrophic receptor tyrosine kinase 1), GDNF (glial cell-derived neurotrophic factor), GFRA1 (GDNF family receptor alpha 1), and GFAP (glial fibrillary acidic protein) in both transplant groups (Tx1 and Tx2). Enhanced expression of these factors was not normalized following the median 28-month period of normoglycemia (Tx1 2nd examination) and negatively correlated with IENF density and with electrophysiological indices of DPN (vibration perception threshold, electromyography, and autonomic tests). In contrast to our expectation, the expression of most of 29 selected factors related to neural regeneration was comparable in subjects with severe peripheral nerve fiber depletion and healthy controls and the expression of six factors was significantly upregulated. These findings may be important for better understanding the pathophysiology of nerve regeneration and for the development of intervention strategies.
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Affiliation(s)
- František Saudek
- Diabetes Center, Institute for Clinical and Experimental Medicine, 14021 Prague, Czech Republic
| | - Monika Cahová
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, 14021 Prague, Czech Republic
| | - Terezie Havrdová
- Diabetes Center, Institute for Clinical and Experimental Medicine, 14021 Prague, Czech Republic
| | - Klára Zacharovová
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, 14021 Prague, Czech Republic
| | - Helena Daňková
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, 14021 Prague, Czech Republic
| | - Luděk Voska
- Clinical and Transplant Pathology Department, Institute for Clinical and Experimental Medicine, 14021 Prague, Czech Republic
| | - Věra Lánská
- Department of Statistics, Institute for Clinical and Experimental Medicine, 14021 Prague, Czech Republic
| | - Nurcan Üçeyler
- University Hospital of Würzburg, Department of Neurology, 97080 Würzburg, Germany
| | - Claudia Sommer
- University Hospital of Würzburg, Department of Neurology, 97080 Würzburg, Germany
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Hsieh YL, Kan HW, Chiang H, Lee YC, Hsieh ST. Distinct TrkA and Ret modulated negative and positive neuropathic behaviors in a mouse model of resiniferatoxin-induced small fiber neuropathy. Exp Neurol 2017; 300:87-99. [PMID: 29106982 DOI: 10.1016/j.expneurol.2017.10.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 10/21/2017] [Accepted: 10/25/2017] [Indexed: 12/18/2022]
Abstract
Neurotrophic factors and their corresponding receptors play key roles in the maintenance of different phenotypic dorsal root ganglion (DRG) neurons, the axons of which degenerate in small fiber neuropathy, leading to various neuropathic manifestations. Mechanisms underlying positive and negative symptoms of small fiber neuropathy have not been systematically explored. This study investigated the molecular basis of these seemingly paradoxical neuropathic behaviors according to the profiles of TrkA and Ret with immunohistochemical and pharmacological interventions in a mouse model of resiniferatoxin (RTX)-induced small fiber neuropathy. Mice with RTX neuropathy exhibited thermal hypoalgesia and mechanical allodynia, reduced skin innervation, and altered DRG expression profiles with decreased TrkA(+) neurons and increased Ret(+) neurons. RTX neuropathy induced the expression of activating transcription factor 3 (ATF3), and ATF3(+) neurons were colocalized with Ret but not with TrkA (P<0.001). As a neuroprotectant, 4-Methylcatechol (4MC) promoted skin reinnervation partially with correlated reversal of the neuropathic behaviors and altered neurochemical expression. Gambogic amide, a selective TrkA agonist, normalized thermal hypoalgesia, and GW441756, a TrkA kinase inhibitor, induced thermal hypoalgesia, which was already reversed by 4MC. Mechanical allodynia was reversed by a Ret kinase inhibitor, AST487, which induced thermal hyperalgesia in naïve mice. The activation of Ret signaling by XIB4035 induced mechanical allodynia and thermal hypoalgesia in RTX neuropathy mice in which the neuropathic behaviors were previously normalized by 4MC. Distinct neurotrophic factor receptors, TrkA and Ret, accounted for negative and positive neuropathic behaviors in RTX-induced small fiber neuropathy, respectively: TrkA for thermal hypoalgesia and Ret for mechanical allodynia and thermal hypoalgesia.
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Affiliation(s)
- Yu-Lin Hsieh
- Department of Anatomy, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan.
| | - Hung-Wei Kan
- Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
| | - Hao Chiang
- Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan; Department of Otology and Laryngology, Harvard Medical School, Boston, MA 02115, USA; Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, Boston, MA 02114, USA
| | - Yi-Chen Lee
- Department of Anatomy, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan
| | - Sung-Tsang Hsieh
- Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan; Department of Neurology, National Taiwan University Hospital, Taipei 10002, Taiwan; Graduate Institute of Brain and Mind Science, College of Medicine, National Taiwan University, Taipei 10051, Taiwan.
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LOW SERUM BRAIN-DERIVED NEUROTROPHIC FACTOR BUT NOT BRAIN-DERIVED NEUROTROPHIC FACTOR GENE VAL66MET POLYMORPHISM IS ASSOCIATED WITH DIABETIC RETINOPATHY IN CHINESE TYPE 2 DIABETIC PATIENTS. Retina 2017; 37:350-358. [PMID: 27355244 DOI: 10.1097/iae.0000000000001132] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND/PURPOSE The aim of our research was to investigate the potential role of brain-derived neurotrophic factor (BDNF) in diabetic retinopathy (DR). Measurement of serum circulating levels of BDNF and analysis of polymorphism of BDNF gene (Val66Met) were applied and compared with diabetic patients without DR. METHODS From February 2014 and March 2015, all eligible patients with Type 2 diabetic mellitus at our hospital were consecutively recruited (N = 404). Their serum BDNF levels were detected by enzyme-linked immunosorbent assay. BDNF val66met polymorphism genotyping was conducted according to the laboratory's standard protocol. At baseline, demographic and clinical data were taken. The relationship of BDNF with DR was investigated with the use of logistic regression models. Receiver operating characteristic curves were used to test the overall accuracy of BDNF and other markers. RESULTS Diabetic patients with DR and vision-threatening DR had significantly lower BDNF levels on admission (P < 0.0001 both). The BDNF genotyping results showed that there was no difference between the diabetic patients with DR and those without DR. Multivariate logistic regression analysis adjusted for common risk factors showed that serum BDNF levels were independent risk factors for DR (odds ratio = 0.86; 95% confidence interval [CI]: 0.80-0.92; P < 0.0001) and vision-threatening DR (odds ratio = 0.79; 95% CI: 0.75-0.85; P < 0.0001). Brain-derived neurotrophic factor improved the area under the receiver operating characteristic curve of the diabetes duration for DR from 0.69 (95% CI: 0.60-0.76) to 0.85 (95% CI: 0.79-0.90; P < 0.01) and for vision-threatening DR from 0.77 (95% CI: 0.67-0.87) to 0.86 (95% CI: 0.80-0.92; P < 0.01). CONCLUSION The present study demonstrated that, rather than Val66Met polymorphism, decreased serum levels of BDNF were associated with DR and vision-threatening DR in Chinese Type 2 diabetic patients, suggesting a possible role of BDNF in the pathogenesis of DR complications.
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Physical Training and Activity in People With Diabetic Peripheral Neuropathy: Paradigm Shift. Phys Ther 2017; 97:31-43. [PMID: 27445060 PMCID: PMC6256941 DOI: 10.2522/ptj.20160124] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Accepted: 07/11/2016] [Indexed: 12/31/2022]
Abstract
Diabetic peripheral neuropathy (DPN) occurs in more than 50% of people with diabetes and is an important risk factor for skin breakdown, amputation, and reduced physical mobility (ie, walking and stair climbing). Although many beneficial effects of exercise for people with diabetes have been well established, few studies have examined whether exercise provides comparable benefits to people with DPN. Until recently, DPN was considered to be a contraindication for walking or any weight-bearing exercise because of concerns about injuring a person's insensitive feet. These guidelines were recently adjusted, however, after research demonstrated that weight-bearing activities do not increase the risk of foot ulcers in people who have DPN but do not have severe foot deformity. Emerging research has revealed positive adaptations in response to overload stress in these people, including evidence for peripheral neuroplasticity in animal models and early clinical trials. This perspective article reviews the evidence for peripheral neuroplasticity in animal models and early clinical trials, as well as adaptations of the integumentary system and the musculoskeletal system in response to overload stress. These positive adaptations are proposed to promote improved function in people with DPN and to foster the paradigm shift to including weight-bearing exercise for people with DPN. This perspective article also provides specific assessment and treatment recommendations for this important, high-risk group.
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Abstract
PURPOSE OF REVIEW Poor management of chronic pain remains a significant cause of misery with huge socioeconomic costs. Accumulating research in potassium (K+) channel physiology has uncovered several promising leads for the development of novel analgesics. RECENT FINDINGS We now recognize that certain K+ channel subunits are directly gated to pain-relevant stimuli (Kv1.1, K2P) whereas others are specifically modulated by inflammatory processes (Kv7, BKCA, K2P). Genetic analyses illustrate that K+ channel gene variation can predict pain sensitivity (KCNS1, GIRKs), risk for persistent pain (KCNS1, GIRKs, TRESK) and analgesic effectiveness (GIRK2). Importantly, preclinical studies confirm that K+ channel dysfunction can be a pain trigger in traumatic neuropathies (Kv9.1/Kv2.1, Kv7, Kv1.2) and migraine (TRESK). Finally, emerging data suggest that even pain in diabetes, bone cancer and autoimmune neuropathies may have K+ channel dysfunction constituents. SUMMARY There is a long-sought need for superior pharmacotherapy of pain syndromes. Although universal enhancement of K+ channel function in the periphery can decrease nociceptive excitability irrespective of the underlying cause, a more refined targeting of subunits with dominant nociceptive roles could yield highly efficacious treatments with fewer side-effects. The ongoing characterization of molecular interactions linking K+ channel dysfunction to pain is instrumental for identifying candidates with the most therapeutic potential.
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Li B, Lang N, Cheng ZF. Serum Levels of Brain-Derived Neurotrophic Factor Are Associated with Diabetes Risk, Complications, and Obesity: a Cohort Study from Chinese Patients with Type 2 Diabetes. Mol Neurobiol 2015; 53:5492-9. [PMID: 26454822 DOI: 10.1007/s12035-015-9461-2] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 09/25/2015] [Indexed: 12/21/2022]
Abstract
Brain-derived neurotrophic factor (BDNF) is associated with systemic inflammatory conditions, such as diabetes. The aim of this study was to assess the serum BDNF levels in Chinese patients with type 2 diabetes (T2DM). From the outpatient clinic at the endocrinology department of our hospital, all patients with long-standing T2DM were recruited for this study between August 2014 and December 2014. Serum levels of BDNF were assayed with solid-phase sandwich ELISA, and the demographical and clinical data were evaluated on admission. Median serum BDNF levels were significantly lower in patients with T2DM compared to control subjects (15.9 ng/mL (interquartile range (IQR), 12.6-19.8) VS. 24.6 ng/mL (IQR, 17.2-27.8); P < 0.0001). Serum BDNF levels were inversely correlated with fasting glucose (r = -0.394, P < 0.0001) and duration of illness (r = -0.272, P < 0.0001) in T2DM patients. Based on the receiver operating characteristic (ROC) curve, the optimal cutoff value of serum BDNF levels as an indicator for diagnosis of T2DM was projected to be 23.0 ng/mL, which yielded a sensitivity of 89.0 % and a specificity of 60.9 %, with the area under the curve at 0.794 (95 % confidence interval (CI), 0.747-0.841; P < 0.001). In multivariate logistic regression analysis, after adjusting for other significant factors, BDNF can be seen as an indicator of independent diabetes complications with an odds ratio (OR) of 0.84 (95 % CI, 0.75-0.89; P < 0.001) and obesity with an OR of 0.88 (95 % CI, 0.80-0.92; P < 0.001). Our study suggested that low levels of BDNF accompany impaired glucose metabolism. Importantly, we found that decreased BDNF were correlated with obesity and diabetes complications.
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Affiliation(s)
- Bo Li
- Department of Endocrinology and Metabolic Disease, The Fourth Affiliated Hospital of Harbin Medical University, No. 37, Yiyuan Street, Harbin, 150001, People's Republic of China
| | - Ning Lang
- Department of Endocrinology and Metabolic Disease, The Fourth Affiliated Hospital of Harbin Medical University, No. 37, Yiyuan Street, Harbin, 150001, People's Republic of China
| | - Zhi-Feng Cheng
- Department of Endocrinology and Metabolic Disease, The Fourth Affiliated Hospital of Harbin Medical University, No. 37, Yiyuan Street, Harbin, 150001, People's Republic of China.
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Hoyng SA, de Winter F, Tannemaat MR, Blits B, Malessy MJA, Verhaagen J. Gene therapy and peripheral nerve repair: a perspective. Front Mol Neurosci 2015; 8:32. [PMID: 26236188 PMCID: PMC4502351 DOI: 10.3389/fnmol.2015.00032] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 07/01/2015] [Indexed: 12/19/2022] Open
Abstract
Clinical phase I/II studies have demonstrated the safety of gene therapy for a variety of central nervous system disorders, including Canavan's, Parkinson's (PD) and Alzheimer's disease (AD), retinal diseases and pain. The majority of gene therapy studies in the CNS have used adeno-associated viral vectors (AAV) and the first AAV-based therapeutic, a vector encoding lipoprotein lipase, is now marketed in Europe under the name Glybera. These remarkable advances may become relevant to translational research on gene therapy to promote peripheral nervous system (PNS) repair. This short review first summarizes the results of gene therapy in animal models for peripheral nerve repair. Secondly, we identify key areas of future research in the domain of PNS-gene therapy. Finally, a perspective is provided on the path to clinical translation of PNS-gene therapy for traumatic nerve injuries. In the latter section we discuss the route and mode of delivery of the vector to human patients, the efficacy and safety of the vector, and the choice of the patient population for a first possible proof-of-concept clinical study.
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Affiliation(s)
- Stefan A Hoyng
- Department of Neuroregeneration, Netherlands Institute for Neuroscience Amsterdam, Netherlands ; Department of Neurosurgery, Leiden University Medical Center Leiden, Netherlands
| | - Fred de Winter
- Department of Neuroregeneration, Netherlands Institute for Neuroscience Amsterdam, Netherlands ; Department of Neurosurgery, Leiden University Medical Center Leiden, Netherlands
| | - Martijn R Tannemaat
- Department of Neuroregeneration, Netherlands Institute for Neuroscience Amsterdam, Netherlands ; Department of Neurology, Leiden University Medical Center Leiden, Netherlands
| | | | - Martijn J A Malessy
- Department of Neuroregeneration, Netherlands Institute for Neuroscience Amsterdam, Netherlands ; Department of Neurosurgery, Leiden University Medical Center Leiden, Netherlands
| | - Joost Verhaagen
- Department of Neuroregeneration, Netherlands Institute for Neuroscience Amsterdam, Netherlands ; Center for Neurogenomics and Cognition Research, Neuroscience Campus Amsterdam Amsterdam, Netherlands
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Abstract
Neurotrophins (NTs) belong to a family of trophic factors that regulate the survival, growth and programmed cell death of neurons. In mammals, there are four structurally and functionally related NT proteins, viz. nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin 3 and neurotrophin 4. Most research on NTs to date has focussed on the effects of NGF and BDNF signalling via their respective cognate high affinity neurotrophic tyrosine kinase viz TrkA and TrkB receptors. Apart from the key physiologic roles of NGF and BDNF in peripheral and central nervous system function, NGF and BDNF signalling via TrkA and TrkB receptors respectively have been implicated in mechanisms underpinning neuropathic pain. Additionally, NGF and BDNF signalling via the low-affinity pan neurotrophin receptor at 75 kDa (p75NTR) may also contribute to the pathobiology of neuropathic pain. In this review, we critically assess the role of neurotrophins signalling via their cognate high affinity receptors as well as the low affinity p75NTR in the pathophysiology of peripheral neuropathic and central neuropathic pain. We also identify knowledge gaps to guide future research aimed at generating novel insight on how to optimally modulate NT signalling for discovery of novel therapeutics to improve neuropathic pain relief.
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