1
|
Pietrzak BA, Wnuk A, Przepiórska K, Łach A, Kajta M. Posttreatment with Ospemifene Attenuates Hypoxia- and Ischemia-Induced Apoptosis in Primary Neuronal Cells via Selective Modulation of Estrogen Receptors. Neurotox Res 2023; 41:362-379. [PMID: 37129835 PMCID: PMC10354152 DOI: 10.1007/s12640-023-00644-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/17/2023] [Accepted: 04/02/2023] [Indexed: 05/03/2023]
Abstract
Stroke and perinatal asphyxia have detrimental effects on neuronal cells, causing millions of deaths worldwide each year. Since currently available therapies are insufficient, there is an urgent need for novel neuroprotective strategies to address the effects of cerebrovascular accidents. One such recent approach is based on the neuroprotective properties of estrogen receptors (ERs). However, activation of ERs by estrogens may contribute to the development of endometriosis or hormone-dependent cancers. Therefore, in this study, we utilized ospemifene, a novel selective estrogen receptor modulator (SERM) already used in dyspareunia treatment. Here, we demonstrated that posttreatment with ospemifene in primary neocortical cell cultures subjected to 18 h of hypoxia and/or ischemia followed by 6 h of reoxygenation has robust neuroprotective potential. Ospemifene partially reverses hypoxia- and ischemia-induced changes in LDH release, the degree of neurodegeneration, and metabolic activity. The mechanism of the neuroprotective actions of ospemifene involves the inhibition of apoptosis since the compound decreases caspase-3 overactivity during hypoxia and enhances mitochondrial membrane potential during ischemia. Moreover, in both models, ospemifene decreased the levels of the proapoptotic proteins BAX, FAS, FASL, and GSK3β while increasing the level of the antiapoptotic protein BCL2. Silencing of specific ERs showed that the neuroprotective actions of ospemifene are mediated mainly via ESR1 (during hypoxia and ischemia) and GPER1 (during hypoxia), which is supported by ospemifene-evoked increases in ESR1 protein levels in hypoxic and ischemic neurons. The results identify ospemifene as a promising neuroprotectant, which in the future may be used to treat injuries due to brain hypoxia/ischemia.
Collapse
Affiliation(s)
- Bernadeta A Pietrzak
- Laboratory of Neuropharmacology and Epigenetics, Department of Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna Street 12, Krakow, 31-343, Poland
| | - Agnieszka Wnuk
- Laboratory of Neuropharmacology and Epigenetics, Department of Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna Street 12, Krakow, 31-343, Poland
| | - Karolina Przepiórska
- Laboratory of Neuropharmacology and Epigenetics, Department of Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna Street 12, Krakow, 31-343, Poland
| | - Andrzej Łach
- Laboratory of Neuropharmacology and Epigenetics, Department of Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna Street 12, Krakow, 31-343, Poland
| | - Małgorzata Kajta
- Laboratory of Neuropharmacology and Epigenetics, Department of Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna Street 12, Krakow, 31-343, Poland.
| |
Collapse
|
2
|
Gu Q, Sarkar S, Raymick B, Kanungo J. Combining tissue clearing and Fluoro-Jade C labeling for neurotoxicity assessments. Exp Biol Med (Maywood) 2023; 248:605-611. [PMID: 37208909 PMCID: PMC10350804 DOI: 10.1177/15353702231165009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 03/02/2023] [Indexed: 05/21/2023] Open
Abstract
Tissue clearing refers to laboratory methods that make tissue transparent by chemical means. This approach allows the labeling, visualization, and analysis of specific targets without cutting the tissue into sections, thereby maintaining three-dimensional architecture. More than two dozen tissue-clearing methods have been developed by different research teams to date. While tissue clearing has been successfully applied in several studies concerning basic science or diseases, little is known about the utilization of tissue clearing for neurotoxicity evaluation. In this study, several tissue-clearing methods were combined with Fluoro-Jade C (FJ-C), a standard marker of neurodegeneration. The results suggest that some but not all tissue-clearing media are compatible with the FJ-C fluorophore. By utilizing a neurotoxicity animal model, the results further suggest that FJ-C labeling can be combined with tissue clearing for neurotoxicity assessments. This approach has the potential to be expanded further by combining multicolor labeling of molecular targets involved in the development and/or mechanisms of neurotoxicity and neurodegeneration.
Collapse
Affiliation(s)
- Qiang Gu
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA
| | - Sumit Sarkar
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA
| | - Bryan Raymick
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA
| | - Jyotshna Kanungo
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA
| |
Collapse
|
3
|
Ma Z, Liu K, Zhang RF, Xie ZX, Liu W, Deng Y, Li X, Xu B. Manganese-induced α-synuclein overexpression promotes the accumulation of dysfunctional synaptic vesicles and hippocampal synaptotoxicity by suppressing Rab26-dependent autophagy in presynaptic neurons. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159753. [PMID: 36341850 DOI: 10.1016/j.scitotenv.2022.159753] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 10/02/2022] [Accepted: 10/23/2022] [Indexed: 06/16/2023]
Abstract
Manganese (Mn) overexposure induces learning and memory impairments in mice by disrupting the functions of synapses and synaptic vesicles (SVs) in the hippocampus, which is associated with α-synuclein (α-Syn) overexpression. Rab26-dependent autophagy is a key signaling step required for impaired SV clearance; however, it is unclear whether Mn-induced α-Syn overexpression is linked to dysregulated Rab26-dependent autophagy in presynaptic neurons. In this study, we developed manganism models in male C57BL/6 mice and hippocampal primary neurons to observe the associations between Mn-induced α-Syn overexpression and impaired SV accumulation. The results of the in vivo experiments showed that 100 and 200 μmol/kg Mn exposure significantly impaired memory and synaptic plasticity in the mice, which was related to the accumulation of impaired SVs in the hippocampus. Consistent with the in vivo outcomes, the level of in vitro injured SVs in the 50 and 100 μmol/L Mn-exposed neuron group were higher than that in the control group. Moreover, 100 μmol/L Mn suppressed the initiation of Rab26-dependent autophagy at the synapse. Then, we transfected neurons with LV-α-Syn short hairpin RNA (shRNA) and exposed the neurons to Mn for an additional 24 h. Surprisingly, the area of colocalization between Rab26 and Atg16L1 and the expression level of LC3II-positive SVs were both higher in Mn-exposed LV-α-Syn shRNA-transfected neurons than those in Mn-treated normal or Mn-treated LV-scrambled shRNA-transfected neurons. Thus, Mn-induced α-Syn overexpression was responsible for the dysregulation of Rab26-dependent autophagy, thereby promoting the accumulation of injured SVs, and causing synaptotoxicity and cognitive and memory deficits in mice.
Collapse
Affiliation(s)
- Zhuo Ma
- Department of Environmental Health, School of Public Health, China Medical University, People's Republic of China
| | - Kuan Liu
- Department of Environmental Health, School of Public Health, China Medical University, People's Republic of China
| | - Rui-Feng Zhang
- Department of Environmental Health, School of Public Health, China Medical University, People's Republic of China
| | - Zi-Xin Xie
- Department of Environmental Health, School of Public Health, China Medical University, People's Republic of China
| | - Wei Liu
- Department of Environmental Health, School of Public Health, China Medical University, People's Republic of China
| | - Yu Deng
- Department of Environmental Health, School of Public Health, China Medical University, People's Republic of China
| | - Xin Li
- Department of Occupational Health, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, 110122 Shenyang, Liaoning Province, People's Republic of China.
| | - Bin Xu
- Department of Environmental Health, School of Public Health, China Medical University, People's Republic of China.
| |
Collapse
|
4
|
Gan Q, Wong A, Zhang Z, Na H, Tian H, Tao Q, Rajab IM, Potempa LA, Qiu WQ. Monomeric C‐reactive protein induces the cellular pathology of Alzheimer's disease. ALZHEIMER'S & DEMENTIA: TRANSLATIONAL RESEARCH & CLINICAL INTERVENTIONS 2022; 8:e12319. [PMID: 35846159 PMCID: PMC9270638 DOI: 10.1002/trc2.12319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 05/17/2022] [Accepted: 06/01/2022] [Indexed: 11/19/2022]
Abstract
Introduction Human study shows that elevated C‐reactive protein (CRP) in blood impacts apolipoprotein E (APOE) ε4, but not APOE ε3 or APOE ε2, genotype to increase the risk of Alzheimer's disease (AD). However, whether CRP is directly involved in cellular AD pathogenesis and in which type of neuronal cells of APOE ε4 carriers are unknown. Methods We aimed to use different primary neuronal cells and investigate if CRP induces cellular AD pathology depending on APOE genotypes. Here the different primary neuronal cells from the different APOE genotype knock‐in mice cortex were isolated and used. Results Monomeric CRP (mCRP) increased amyloid beta production and, in parallel, induced tau phosphorylation in addition to their related proteins in the primary neurons in a pattern of APOE ε4 > APOE ε3 > APOE ε2 in a dose‐ and time‐dependent manner. Consistently, mCRP induced the staining of other neurodegenerative biomarkers, including Fluoro‐Jade B stain (FjB), TUNEL and Cleaved Caspase‐3, in primary neurons in a similar pattern of APOE ε4 > APOE ε3 > APOE ε2. In contrast, pentameric CRP (pCRP) had a tendency to induce cellular AD pathology but did not reach statistical significance. On the other hand, it is intriguing that regardless of APOE genotype, mCRP did not influence the expressions of Iba‐1 and CD68 in primary microglia or the expression of glial fibrillary acidic protein in primary astrocytes, and additionally mCRP did not affect the secretions of interleukin (IL)‐1α, IL‐1β, and tumor necrosis factor α from these cells. Discussion This is the first report to demonstrate that mCRP directly induces cellular AD pathogenesis in neurons in an APOE genotype‐dependent pattern, suggesting that mCRP plays a role as a mediator involved in the APOE ε4‐related pathway for AD during chronic inflammation. Highlights Pentameric C‐reactive protein (pCRP) can be dissociated irreversibly to form free subunits or monomeric CRP (mCRP) during and after the acute phase. mCRP increased amyloid beta production in the primary neurons in a pattern of apolipoprotein E (APOE) ε4 > APOE ε3 > APOE ε2 in a dose‐dependent manner. mCRP induced the expression of phosphorylated tau in the primary neurons in a pattern of APOE ε4 > APOE ε3 > APOE ε2 in a dose‐ and time‐dependent manner. mCRP plays an important mediator role in the APOE ε4‐related pathway of Alzheimer's disease risk.
Collapse
Affiliation(s)
- Qini Gan
- Department of Pharmacology and Experimental Therapeutics Boston University School of Medicine Boston Massachusetts USA
| | - Alfred Wong
- Department of Pharmacology and Experimental Therapeutics Boston University School of Medicine Boston Massachusetts USA
| | - Zhengrong Zhang
- Department of Pharmacology and Experimental Therapeutics Boston University School of Medicine Boston Massachusetts USA
| | - Hana Na
- Department of Pharmacology and Experimental Therapeutics Boston University School of Medicine Boston Massachusetts USA
| | - Hua Tian
- Department of Pharmacology and Experimental Therapeutics Boston University School of Medicine Boston Massachusetts USA
- Department of Pharmacology Xiaman Medical College Xiaman People's Republic of China
| | - Qiushan Tao
- Department of Pharmacology and Experimental Therapeutics Boston University School of Medicine Boston Massachusetts USA
| | - Ibraheem M. Rajab
- Roosevelt University College of Science Health and Pharmacy Schaumburg Illinois USA
| | - Lawrence A. Potempa
- Roosevelt University College of Science Health and Pharmacy Schaumburg Illinois USA
| | - Wei Qiao Qiu
- Department of Pharmacology and Experimental Therapeutics Boston University School of Medicine Boston Massachusetts USA
- Alzheimer's Disease Center Boston University School of Medicine Boston Massachusetts USA
- Department of Psychiatry Boston University School of Medicine Boston Massachusetts USA
| |
Collapse
|
5
|
Post-Treatment with Amorfrutin B Evokes PPARγ-Mediated Neuroprotection against Hypoxia and Ischemia. Biomedicines 2021; 9:biomedicines9080854. [PMID: 34440058 PMCID: PMC8389580 DOI: 10.3390/biomedicines9080854] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/14/2021] [Accepted: 07/19/2021] [Indexed: 12/14/2022] Open
Abstract
In this study, we demonstrate for the first time that amorfrutin B, a selective modulator of peroxisome proliferator-activated receptor gamma—PPARγ, can protect brain neurons from hypoxia- and ischemia-induced degeneration when applied at 6 h post-treatment in primary cultures. The neuroprotective effect of amorfrutin B suggests that it promotes mitochondrial integrity and is capable of inhibiting reactive oxygen species—ROS activity and ROS-mediated DNA damage. PPARγ antagonist and Pparg mRNA silencing abolished the neuroprotective effect of amorfrutin B, which points to agonistic action of the compound on the respective receptor. Interestingly, amorfrutin B stimulated the methylation of the Pparg gene, both during hypoxia and ischemia. Amorfrutin B also increased the protein level of PPARγ during hypoxia but decreased the mRNA and protein levels of PPARγ during ischemia. Under ischemic conditions, amorfrutin B-evoked hypermethylation of the Pparg gene is in line with the decrease in the mRNA and protein expression of PPARγ. However, under hypoxic conditions, amorfrutin B-dependent hypermethylation of the Pparg gene does not explain the amorfrutin B-dependent increase in receptor protein expression, which suggests other regulatory mechanisms. Other epigenetic parameters, such as HAT and/or sirtuins activities, were affected by amorfrutin B under hypoxic and ischemic conditions. These properties position the compound among the most promising anti-stroke and wide-window therapeutics.
Collapse
|
6
|
Ikenari T, Kurata H, Satoh T, Hata Y, Mori T. Evaluation of Fluoro-Jade C Staining: Specificity and Application to Damaged Immature Neuronal Cells in the Normal and Injured Mouse Brain. Neuroscience 2020; 425:146-156. [DOI: 10.1016/j.neuroscience.2019.11.029] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 09/30/2019] [Accepted: 11/18/2019] [Indexed: 12/22/2022]
|
7
|
Gutiérrez IL, González-Prieto M, García-Bueno B, Caso JR, Leza JC, Madrigal JLM. Alternative Method to Detect Neuronal Degeneration and Amyloid β Accumulation in Free-Floating Brain Sections With Fluoro-Jade. ASN Neuro 2019; 10:1759091418784357. [PMID: 29950099 PMCID: PMC6043921 DOI: 10.1177/1759091418784357] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Fluoro-Jade is a fluorescein-derived fluorochrome which specifically binds to damaged neurons. Due to this characteristic, it is commonly used for the histochemical detection and quantification of neurodegeneration in mounted brain sections. Here, we describe an alternative and simpler histochemistry protocol based on the use of free-floating brain sections. For this purpose, we have used brain slices from wild-type and 5xFAD mice as well as from mice that received an intracerebral injection of oligomeric amyloid beta peptides. We observed that our histochemistry staining procedure allows for a well-defined labeling of degenerating neurons providing a better signal-to-noise ratio staining than the commonly used one. In addition, our modified protocol demonstrates the ability of Fluoro-Jade C to also fluorescently label amyloid beta plaques.
Collapse
Affiliation(s)
- Irene L. Gutiérrez
- Department of Pharmacology, School of Medicine, Universidad Complutense de Madrid (UCM), Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Investigación Neuroquímica (IUINQ-UCM) and Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12), Madrid, Spain
| | - Marta González-Prieto
- Department of Pharmacology, School of Medicine, Universidad Complutense de Madrid (UCM), Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Investigación Neuroquímica (IUINQ-UCM) and Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12), Madrid, Spain
| | - Borja García-Bueno
- Department of Pharmacology, School of Medicine, Universidad Complutense de Madrid (UCM), Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Investigación Neuroquímica (IUINQ-UCM) and Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12), Madrid, Spain
| | - Javier R. Caso
- Department of Pharmacology, School of Medicine, Universidad Complutense de Madrid (UCM), Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Investigación Neuroquímica (IUINQ-UCM) and Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12), Madrid, Spain
| | - Juan C. Leza
- Department of Pharmacology, School of Medicine, Universidad Complutense de Madrid (UCM), Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Investigación Neuroquímica (IUINQ-UCM) and Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12), Madrid, Spain
| | - José L. M. Madrigal
- Department of Pharmacology, School of Medicine, Universidad Complutense de Madrid (UCM), Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Investigación Neuroquímica (IUINQ-UCM) and Instituto de Investigación Sanitaria Hospital 12 de Octubre (Imas12), Madrid, Spain
- José L. M. Madrigal, Dpto. Farmacología, Fac. Medicina, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040 Madrid, Spain.
| |
Collapse
|
8
|
Gu Q, Cuevas E, Ali SF, Paule MG, Krauthamer V, Jones Y, Zhang Y. An Alternative In Vitro Method for Examining Nanoparticle-Induced Cytotoxicity. Int J Toxicol 2019; 38:385-394. [PMID: 31234669 DOI: 10.1177/1091581819859267] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Conventional in vitro assays are often used as initial screens to identify potential toxic effects of nanoparticles (NPs). However, many NPs have shown interference with conventional in vitro assays, resulting in either false-positive or -negative outcomes. Here, we report an alternative method for the in vitro assessment of NP-induced cytotoxicity utilizing Fluoro-Jade C (FJ-C). To provide proof of concept and initial validation data, Ag-NPs and Au-NPs were tested in 3 different cell cultures including rat brain microvessel endothelial cells, mouse neural stem cells, and the human SH-SY5Y cell line. Conventional 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) and lactate dehydrogenase (LDH) assays were run in parallel with the new method and served as references. The results demonstrate for the first time that FJ-C labeling can be a useful tool for assessing NP-induced cytotoxicity in vitro. Using these approaches, it was also demonstrated that removal of Ag-NPs-while keeping the Ag-ions that were released from the Ag-NPs in culture media-abolished the measured cytotoxicity, indicating that Ag-NPs rather than Ag-ions in solution contributed to the observed cytotoxic effects. Further, co-treatment of Ag-NPs with N-acetyl cysteine (NAC) prevented the observed cytotoxicity, suggesting a protective role of NAC in Ag-NP-induced cytotoxicity. Thus, this alternative in vitro assay is well suited for identify potential cytotoxicity associated with exposure to NPs.
Collapse
Affiliation(s)
- Qiang Gu
- Division of Neurotoxicology, National Center for Toxicological Research (NCTR), U.S. Food and Drug Administration (FDA), Jefferson, AR, USA
| | - Elvis Cuevas
- Division of Neurotoxicology, National Center for Toxicological Research (NCTR), U.S. Food and Drug Administration (FDA), Jefferson, AR, USA
| | - Syed F Ali
- Division of Neurotoxicology, National Center for Toxicological Research (NCTR), U.S. Food and Drug Administration (FDA), Jefferson, AR, USA
| | - Merle G Paule
- Division of Neurotoxicology, National Center for Toxicological Research (NCTR), U.S. Food and Drug Administration (FDA), Jefferson, AR, USA
| | - Victor Krauthamer
- Division of Biomedical Physics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, FDA, Jefferson, AR, USA
| | - Yvonne Jones
- Nanotechnology Core Facility, Office of Scientific Coordination, NCTR, FDA, Jefferson, AR, USA
| | - Yongbin Zhang
- Nanotechnology Core Facility, Office of Scientific Coordination, NCTR, FDA, Jefferson, AR, USA
| |
Collapse
|
9
|
Alder J, Fujioka W, Giarratana A, Wissocki J, Thakkar K, Vuong P, Patel B, Chakraborty T, Elsabeh R, Parikh A, Girn HS, Crockett D, Thakker-Varia S. Genetic and pharmacological intervention of the p75NTR pathway alters morphological and behavioural recovery following traumatic brain injury in mice. Brain Inj 2015; 30:48-65. [PMID: 26579945 DOI: 10.3109/02699052.2015.1088963] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
PRIMARY OBJECTIVE Neurotrophin levels are elevated after TBI, yet there is minimal regeneration. It was hypothesized that the pro-neurotrophin/p75NTR pathway is induced more than the mature neurotrophin/Trk pathway and that interfering with p75 signalling improves recovery following TBI. RESEARCH DESIGN Lateral Fluid Percussion (LFP) injury was performed on wildtype and p75 mutant mice. In addition, TrkB agonist 7,8 Dihydroxyflavone or p75 antagonist TAT-Pep5 were tested. Western blot and immunohistochemistry revealed biochemical and cellular changes. Morris Water Maze and Rotarod tests demonstrated cognitive and vestibulomotor function. MAIN OUTCOMES AND RESULTS p75 was up-regulated and TrkB was down-regulated 1 day post-LFP. p75 mutant mice as well as mice treated with the p75 antagonist or the TrkB agonist exhibited reduced neuronal death and degeneration and less astrocytosis. The cells undergoing apoptosis appear to be neurons rather than glia. There was improved motor function and spatial learning in p75 mutant mice and mice treated with the p75 antagonist. CONCLUSIONS Many of the pathological and behavioural consequences of TBI might be due to activation of the pro-neurotrophin/p75 toxic pathway overriding the protective mechanisms of the mature neurotrophin/Trk pathway. Targeting p75 can be a novel strategy to counteract the damaging effects of TBI.
Collapse
MESH Headings
- Animals
- Apoptosis/physiology
- Astrocytes/metabolism
- Astrocytes/pathology
- Brain Injuries, Traumatic/drug therapy
- Brain Injuries, Traumatic/genetics
- Brain Injuries, Traumatic/metabolism
- Brain-Derived Neurotrophic Factor/metabolism
- Cognition/physiology
- Flavones/pharmacology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Mutant Strains
- Nerve Growth Factors/metabolism
- Receptor, trkB/agonists
- Receptor, trkB/genetics
- Receptor, trkB/metabolism
- Receptors, Nerve Growth Factor/antagonists & inhibitors
- Receptors, Nerve Growth Factor/genetics
- Receptors, Nerve Growth Factor/metabolism
- Sensory Receptor Cells/metabolism
- Sensory Receptor Cells/pathology
Collapse
Affiliation(s)
- Janet Alder
- a Rutgers Robert Wood Johnson Medical School , Piscataway , NJ , USA
| | - Wendy Fujioka
- a Rutgers Robert Wood Johnson Medical School , Piscataway , NJ , USA
| | - Anna Giarratana
- a Rutgers Robert Wood Johnson Medical School , Piscataway , NJ , USA
| | - Jenna Wissocki
- a Rutgers Robert Wood Johnson Medical School , Piscataway , NJ , USA
| | - Keya Thakkar
- a Rutgers Robert Wood Johnson Medical School , Piscataway , NJ , USA
| | - Phung Vuong
- a Rutgers Robert Wood Johnson Medical School , Piscataway , NJ , USA
| | - Bijal Patel
- a Rutgers Robert Wood Johnson Medical School , Piscataway , NJ , USA
| | | | - Rami Elsabeh
- a Rutgers Robert Wood Johnson Medical School , Piscataway , NJ , USA
| | - Ankit Parikh
- a Rutgers Robert Wood Johnson Medical School , Piscataway , NJ , USA
| | - Hartaj S Girn
- a Rutgers Robert Wood Johnson Medical School , Piscataway , NJ , USA
| | - David Crockett
- a Rutgers Robert Wood Johnson Medical School , Piscataway , NJ , USA
| | | |
Collapse
|
10
|
Thakker-Varia S, Behnke J, Doobin D, Dalal V, Thakkar K, Khadim F, Wilson E, Palmieri A, Antila H, Rantamaki T, Alder J. VGF (TLQP-62)-induced neurogenesis targets early phase neural progenitor cells in the adult hippocampus and requires glutamate and BDNF signaling. Stem Cell Res 2014; 12:762-77. [PMID: 24747217 PMCID: PMC4991619 DOI: 10.1016/j.scr.2014.03.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 02/24/2014] [Accepted: 03/18/2014] [Indexed: 01/19/2023] Open
Abstract
The neuropeptide VGF (non-acronymic), which has antidepressant-like effects, enhances adult hippocampal neurogenesis as well as synaptic activity and plasticity in the hippocampus, however the interaction between these processes and the mechanism underlying this regulation remain unclear. In this study, we demonstrate that VGF-derived peptide TLQP-62 specifically enhances the generation of early progenitor cells in nestin-GFP mice. Specifically, TLQP-62 significantly increases the number of Type 2a neural progenitor cells (NPCs) while reducing the number of more differentiated Type 3 cells. The effect of TLQP-62 on proliferation rather than differentiation was confirmed using NPCs in vitro; TLQP-62 but not scrambled peptide PEHN-62 increases proliferation in a cell line as well as in primary progenitors from adult hippocampus. Moreover, TLQP-62 but not scrambled peptide increases Cyclin D mRNA expression. The proliferation of NPCs induced by TLQP-62 requires synaptic activity, in particular through NMDA and metabotropic glutamate receptors. The activation of glutamate receptors by TLQP-62 activation induces phosphorylation of CaMKII through NMDA receptors and protein kinase D through metabotropic glutamate receptor 5 (mGluR5). Furthermore, pharmacological antagonists to CaMKII and PKD inhibit TLQP-62-induced proliferation of NPCs indicating that these signaling molecules downstream of glutamate receptors are essential for the actions of TLQP-62 on neurogenesis. We also show that TLQP-62 gradually activates Brain-Derived Neurotrophic Factor (BDNF)-receptor TrkB in vitro and that Trk signaling is required for TLQP-62-induced proliferation of NPCs. Understanding the precise molecular mechanism of how TLQP-62 influences neurogenesis may reveal mechanisms by which VGF-derived peptides act as antidepressant-like agents.
Collapse
Affiliation(s)
- Smita Thakker-Varia
- Department of Neuroscience and Cell Biology, Rutgers University - Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
| | - Joseph Behnke
- Department of Neuroscience and Cell Biology, Rutgers University - Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
| | - David Doobin
- Department of Neuroscience and Cell Biology, Rutgers University - Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
| | - Vidhi Dalal
- Department of Neuroscience and Cell Biology, Rutgers University - Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
| | - Keya Thakkar
- Department of Neuroscience and Cell Biology, Rutgers University - Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
| | - Farah Khadim
- Department of Neuroscience and Cell Biology, Rutgers University - Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
| | - Elizabeth Wilson
- Department of Neuroscience and Cell Biology, Rutgers University - Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
| | - Alicia Palmieri
- Department of Neuroscience and Cell Biology, Rutgers University - Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
| | - Hanna Antila
- Neuroscience Center, University of Helsinki, P.O. Box 56, Viikinkaari 4, 00014 Helsinki, Finland.
| | - Tomi Rantamaki
- Neuroscience Center, University of Helsinki, P.O. Box 56, Viikinkaari 4, 00014 Helsinki, Finland.
| | - Janet Alder
- Department of Neuroscience and Cell Biology, Rutgers University - Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
| |
Collapse
|