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Guo JJ, Liu F, Sun X, Huang JJ, Xu M, Sun FY. Bcl-2 enhances the formation of newborn striatal long-projection neurons in adult rat brain after a transient ischemic stroke. Neurosci Bull 2012; 28:669-79. [PMID: 23225311 DOI: 10.1007/s12264-012-1288-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Accepted: 08/07/2012] [Indexed: 01/02/2023] Open
Abstract
OBJECTIVE It has been reported that B-cell lymphoma 2 (Bcl-2) enhances neurogenesis as well as supporting axonal growth after injury. In the present study, we investigated whether Bcl-2 overexpression plays a role in the formation of newborn striatonigral projection neurons in the adult rat brain after transient middle cerebral artery occlusion (MCAO). METHODS We infused human Bcl-2-expressing plasmid (pBcl-2) into the lateral ventricle immediately after 30 min of MCAO, injected 5'-bromodeoxyuridine (BrdU) intraperitoneally to label proliferative cells, and microinjected fluorogold (FG) into the substantia nigra at 11 weeks of reperfusion followed by multiple immunostaining of striatonigral projection neurons at 12 weeks. RESULTS We found that pBcl-2 treatment significantly increased the number of newborn neurons (BrdU(+)-NeuN(+)) in the striatum ipsilateral to the MCAO. We further detected newborn striatonigral projection neurons (BrdU(+)-FG(+)-NeuN(+)) in the ipsilateral striatum at 12 weeks. More interestingly, the number of newborn striatonigral projection neurons (BrdU(+)-FG(+)) was significantly increased by pBcl-2 treatment compared to that by pEGFP, a control plasmid. CONCLUSION Taken together, we found that Bcl-2 overexpression in the brain enhanced the generation of newborn striatonigral projection neurons. This provides a potential strategy for promoting the reestablishment of neural networks and brain repair after ischemic injury.
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Affiliation(s)
- Jian-Jun Guo
- Department of Neurobiology and Institute of Stem Cell Research, Institutes for Biomedical Science, Shanghai Medical College, Fudan University, Shanghai 200032, China
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202
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Choi YS, Karelina K, Alzate-Correa D, Hoyt KR, Impey S, Arthur JS, Obrietan K. Mitogen- and stress-activated kinases regulate progenitor cell proliferation and neuron development in the adult dentate gyrus. J Neurochem 2012; 123:676-88. [PMID: 23020821 PMCID: PMC3575744 DOI: 10.1111/jnc.12035] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Revised: 08/21/2012] [Accepted: 09/25/2012] [Indexed: 01/19/2023]
Abstract
The neurogenic niche within the subgranular zone (SGZ) of the dentate gyrus is a source of new neurons throughout life. Interestingly, SGZ proliferative capacity is regulated by both physiological and pathophysiological conditions. One outstanding question involves the molecular mechanisms that regulate both basal and inducible adult neurogenesis. Here, we examined the role of the MAPK-regulated kinases, mitogen- and stress-activated kinase (MSK)1 and MSK2. as regulators of dentate gyrus SGZ progenitor cell proliferation and neurogenesis. Under basal conditions, MSK1/2 null mice exhibited significantly reduced progenitor cell proliferation capacity and a corollary reduction in the number of doublecortin (DCX)-positive immature neurons. Strikingly, seizure-induced progenitor proliferation was totally blocked in MSK1/2 null mice. This blunting of cell proliferation in MSK1/2 null mice was partially reversed by forskolin infusion, indicating that the inducible proliferative capacity of the progenitor cell population was intact. Furthermore, in MSK1/2 null mice, DCX-positive immature neurons exhibited reduced neurite arborization. Together, these data reveal a critical role for MSK1/2 as regulators of both basal and activity-dependent progenitor cell proliferation and morphological maturation in the SGZ.
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Affiliation(s)
- Yun-Sik Choi
- Department of Pharmaceutical Science & Technology, Catholic University of Daegu, Gyeongbuk, Rep. of Korea
| | - Kate Karelina
- Department of Neuroscience, Ohio State University, Columbus, OH 43210
| | | | - Kari R. Hoyt
- Division of Pharmacology, Ohio State University, Columbus, OH 43210
| | - Soren Impey
- Department of Cell and Developmental Biology, Oregon Health & Sciences University, Portland, OR 97239
| | - J. Simon Arthur
- MRC Protein Phosphorylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, U.K
| | - Karl Obrietan
- Department of Neuroscience, Ohio State University, Columbus, OH 43210
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203
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Kakinohana O, Juhasova J, Juhas S, Motlik J, Platoshyn O, Galik J, Hefferan M, Yuan SH, Vidal JG, Carson CT, Van Gorp S, Goldberg D, Leerink M, Lazar P, Marsala S, Miyanohara A, Keshavarzi S, Ciacci JD, Marsala M. Survival and Differentiation of Human Embryonic Stem Cell-Derived Neural Precursors Grafted Spinally in Spinal Ischemia-Injured Rats or in Naive Immunosuppressed Minipigs: A Qualitative and Quantitative Study. Cell Transplant 2012; 21:2603-19. [DOI: 10.3727/096368912x653200] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
In previous studies, we have demonstrated that spinal grafting of human or rat fetal spinal neural precursors leads to amelioration of spasticity and improvement in ambulatory function in rats with spinal ischemic injury. In the current study, we characterize the survival and maturation of three different human embryonic stem (ES) cell line-derived neural precursors (hNPCs) once grafted into ischemia-injured lumbar spinal cord in rats or in naive immunosuppressed minipigs. Proliferating HUES-2, HUES-7, or HUES-9 colonies were induced to form embryoid bodies. During the nestin-positive stage, the rosettes were removed and CD184+/CD271-/CD44-/CD24+ population of ES-hNPCs FAC-sorted and expanded. Male Sprague–Dawley rats with spinal ischemic injury or naive immunosuppressed Gottingen–Minnesota minipigs received 10 bilateral injections of ES-NPCs into the L2–L5 gray matter. After cell grafting, animals survived for 2 weeks to 4.5 months, and the presence of grafted cells was confirmed after staining spinal cord sections with a combination of human-specific (hNUMA, HO14, hNSE, hSYN) or nonspecific (DCX, MAP2, CHAT, GFAP, APC) antibodies. In the majority of grafted animals, hNUMA-positive grafted cells were identified. At 2–4 weeks after grafting, double-labeled hNUMA/ DCX-immunoreactive neurons were seen with extensive DCX+ processes. At survival intervals of 4–8 weeks, hNSE+ neurons and expression of hSYN was identified. Some hSYN-positive terminals formed putative synapses with the host neurons. Quantitative analysis of hNUMA+ cells at 2 months after grafting showed comparable cell survival for all three cell lines. In the presence of low-level immunosuppression, no grafted cell survival was seen at 4.5 months after grafting. Spinal grafting of proliferating pluripotent HUES-7 cells led to consistent teratoma formation at 2–6 weeks after cell transplantation. These data show that ES-derived, FAC-sorted NPCs can represent an effective source of human NPCs to be used in CNS cell replacement therapies.
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Affiliation(s)
- O. Kakinohana
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego, La Jolla, CA, USA
| | - J. Juhasova
- Institute of Animal Physiology and Genetics, AS CR, Liběchov, Czech Republic
| | - S. Juhas
- Institute of Animal Physiology and Genetics, AS CR, Liběchov, Czech Republic
| | - J. Motlik
- Institute of Animal Physiology and Genetics, AS CR, Liběchov, Czech Republic
| | - O. Platoshyn
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego, La Jolla, CA, USA
| | - J. Galik
- Institute of Neurobiology, Slovak Academy of Sciences, Košice, Slovakia
- Institute of Biology and Ecology, Faculty of Science, Pavol Jozef Safarik University, Košice, Slovakia
| | - M. Hefferan
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego, La Jolla, CA, USA
| | - S. H. Yuan
- Howard Hughes Medical Institute and Department of Cellular and Molecular Medicine, School of Medicine, University of California, San Diego, La Jolla, CA, USA
- Department of Neurosciences, School of Medicine, University of California, San Diego, La Jolla, CA, USA
| | | | | | - S. Van Gorp
- Department of Anesthesiology, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands
| | - D. Goldberg
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego, La Jolla, CA, USA
| | - M. Leerink
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego, La Jolla, CA, USA
| | - P. Lazar
- University of Veterinary Medicine and Pharmacy, Department of Breeding and Diseases of Game and Fish, Košice, Slovakia
| | - S. Marsala
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego, La Jolla, CA, USA
| | - A. Miyanohara
- Vector Core Laboratory, Department of Pediatrics, University of California, San Diego, La Jolla, CA, USA
| | - S. Keshavarzi
- Division of Neurosurgery, University of California, San Diego, La Jolla, CA, USA
| | - J. D. Ciacci
- Division of Neurosurgery, University of California, San Diego, La Jolla, CA, USA
| | - M. Marsala
- Neuroregeneration Laboratory, Department of Anesthesiology, University of California, San Diego, La Jolla, CA, USA
- Institute of Neurobiology, Slovak Academy of Sciences, Košice, Slovakia
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204
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Doeppner TR, Ewert TAS, Tönges L, Herz J, Zechariah A, ElAli A, Ludwig AK, Giebel B, Nagel F, Dietz GPH, Weise J, Hermann DM, Bähr M. Transduction of neural precursor cells with TAT-heat shock protein 70 chaperone: therapeutic potential against ischemic stroke after intrastriatal and systemic transplantation. Stem Cells 2012; 30:1297-310. [PMID: 22593021 DOI: 10.1002/stem.1098] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Novel therapeutic concepts against cerebral ischemia focus on cell-based therapies in order to overcome some of the side effects of thrombolytic therapy. However, cell-based therapies are hampered because of restricted understanding regarding optimal cell transplantation routes and due to low survival rates of grafted cells. We therefore transplanted adult green fluorescence protein positive neural precursor cells (NPCs) either intravenously (systemic) or intrastriatally (intracerebrally) 6 hours after stroke in mice. To enhance survival of NPCs, cells were in vitro protein-transduced with TAT-heat shock protein 70 (Hsp70) before transplantation followed by a systematic analysis of brain injury and underlying mechanisms depending on cell delivery routes. Transduction of NPCs with TAT-Hsp70 resulted in increased intracerebral numbers of grafted NPCs after intracerebral but not after systemic transplantation. Whereas systemic delivery of either native or transduced NPCs yielded sustained neuroprotection and induced neurological recovery, only TAT-Hsp70-transduced NPCs prevented secondary neuronal degeneration after intracerebral delivery that was associated with enhanced functional outcome. Furthermore, intracerebral transplantation of TAT-Hsp70-transduced NPCs enhanced postischemic neurogenesis and induced sustained high levels of brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor, and vascular endothelial growth factor in vivo. Neuroprotection after intracerebral cell delivery correlated with the amount of surviving NPCs. On the contrary, systemic delivery of NPCs mediated acute neuroprotection via stabilization of the blood-brain-barrier, concomitant with reduced activation of matrix metalloprotease 9 and decreased formation of reactive oxygen species. Our findings imply two different mechanisms of action of intracerebrally and systemically transplanted NPCs, indicating that systemic NPC delivery might be more feasible for translational stroke concepts, lacking a need of in vitro manipulation of NPCs to induce long-term neuroprotection.
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Affiliation(s)
- Thorsten R Doeppner
- Department of Neurology, University of Duisburg-Essen Medical School, Essen, Germany; Department of Neurology, University of Goettingen Medical School, Goettingen, Germany.
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205
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Begum N, Wang B, Mori M, Vares G. Does ionizing radiation influence Alzheimer's disease risk? JOURNAL OF RADIATION RESEARCH 2012; 53:815-22. [PMID: 22872779 PMCID: PMC3483841 DOI: 10.1093/jrr/rrs036] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Alzheimer's disease (AD) is a human neurodegenerative disease, and its global prevalence is predicted to increase dramatically in the following decades. There is mounting evidence describing the effects of ionizing radiation (IR) on the brain, suggesting that exposure to IR might ultimately favor the development of AD. Therefore better understanding the possible connections between exposure to IR and AD pathogenesis is of utmost importance. In this review, recent developments in the research on the biological and cognitive effects of IR in the brain will be explored. Because AD is largely an age-related pathology, the effects of IR on ageing will be investigated.
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Affiliation(s)
- Nasrin Begum
- Center for Nuclear Medicine and Ultrasound, Rajshahi Medical College Hospital Campus, GPO Box No. 35, Rajshahi, Bangladesh
- National Institute of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba 263-8555, Japan
| | - Bing Wang
- National Institute of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba 263-8555, Japan
| | - Masahiko Mori
- National Institute of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba 263-8555, Japan
| | - Guillaume Vares
- National Institute of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba 263-8555, Japan
- Corresponding author. Tel: +81-(0)43-206-4730;
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206
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Kim SE, Ko IG, Park CY, Shin MS, Kim CJ, Jee YS. Treadmill and wheel exercise alleviate lipopolysaccharide-induced short-term memory impairment by enhancing neuronal maturation in rats. Mol Med Rep 2012; 7:31-6. [PMID: 23128607 DOI: 10.3892/mmr.2012.1160] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Accepted: 10/18/2012] [Indexed: 11/05/2022] Open
Abstract
Lipopolysaccharide (LPS) is an endotoxin derived from Gram‑negative bacteria, which induces brain inflammation. LPS‑induced brain inflammation deteriorates hippocampus‑dependent cognitive deficits. In the present study, we investigated the effects of forced treadmill exercise and voluntary wheel exercise on short‑term memory in relation to neuronal maturation in LPS‑induced brain inflammation of rats. Brain inflammation in rats was induced by an injection of LPS into the cerebral ventricle. Short‑term memory was evaluated using a step‑down avoidance task. Cell proliferation in the hippocampal dentate gyrus was determined by 5‑bromo‑2'‑deoxyuridine (BrdU), a marker of new cells, immunohistochemistry. Western blot analysis for the determination of doublecortin (DCX), a marker of immature neurons and neuronal nuclear antigen (NeuN), a marker of mature neurons, was performed. In the present study, LPS‑induced brain inflammation impaired short‑term memory by increasing DCX expression and suppressing NeuN expression. These results suggest that LPS‑induced brain inflammation disturbs neuronal maturation. The number of BrdU‑positive cells in the hippocampal dentate gyrus was increased by LPS injection. This increase in the number of BrdU‑positive cells can be ascribed to the increase in the number of of immature neurons following LPS injection. On the other hand, forced treadmill exercise and voluntary wheel exercise improved brain inflammation‑induced short‑term memory impairment by suppressing DCX expression and increasing NeuN expression, enhancing neuronal maturation. Forced treadmill exercise and voluntary wheel exercise showed similar efficacy. From these results, it can be inferred that forced treadmill exercise and voluntary wheel exercise may improve memory function deteriorated by brain inflammation.
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Affiliation(s)
- Sung-Eun Kim
- Department of Physiology, College of Medicine, Kyung Hee University, Seoul 130-701, Republic of Korea
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207
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Sun F, Wang X, Mao X, Xie L, Jin K. Ablation of neurogenesis attenuates recovery of motor function after focal cerebral ischemia in middle-aged mice. PLoS One 2012; 7:e46326. [PMID: 23110048 PMCID: PMC3482223 DOI: 10.1371/journal.pone.0046326] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Accepted: 08/29/2012] [Indexed: 11/28/2022] Open
Abstract
Depletion of neurogenesis worsens functional outcome in young-adult mice after focal cerebral ischemia, but whether a similar effect occurs in older mice is unknown. Using middle-aged (12-month-old) transgenic (DCX-TK(+)) mice that express herpes simplex virus thymidine kinase (HSV-TK) under control of the doublecortin (DCX) promoter, we conditionally depleted DCX-positive cells in the subventricular zone (SVZ) and hippocampus by treatment with ganciclovir (GCV) for 14 days. Focal cerebral ischemia was induced by permanent occlusion of the middle cerebral artery (MCAO) or occlusion of the distal segment of middle cerebral artery (dMCAO) on day 14 of vehicle or GCV treatment and mice were killed 24 hr or 12 weeks later. Increased infarct volume or brain atrophy was found in GCV- compared to vehicle-treated middle-aged DCX-TK(+) mice, both 24 hr after MCAO and 12 weeks after dMCAO. More severe motor deficits were also observed in GCV-treated, middle-aged DCX-TK(+) transgenic mice at both time points. Our results indicate that ischemia-induced newborn neurons contribute to anatomical and functional outcome after experimental stroke in middle-aged mice.
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Affiliation(s)
- Fen Sun
- Department of Pharmacology & Neuroscience, Institute for Aging and Alzheimer's Disease Research, University of North Texas, Fort Worth, Texas, United States of America
| | - Xiaomei Wang
- Buck Institute for Research on Aging, Novato, California, United States of America
| | - XiaoOu Mao
- Buck Institute for Research on Aging, Novato, California, United States of America
| | - Lin Xie
- Buck Institute for Research on Aging, Novato, California, United States of America
| | - Kunlin Jin
- Department of Pharmacology & Neuroscience, Institute for Aging and Alzheimer's Disease Research, University of North Texas, Fort Worth, Texas, United States of America
- Buck Institute for Research on Aging, Novato, California, United States of America
- * E-mail:
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208
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Han H, Wu LM, Han MX, Yang WM, Xie DJ, Fang ZH, Chu DC, Fang F. [Effects of Chinese herbal medicine Shenxiong Yujing Granule on regeneration of neural cells in rats with diabetes-associated cerebral ischemia]. ACTA ACUST UNITED AC 2012; 10:1140-8. [PMID: 23073198 DOI: 10.3736/jcim20121011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To establish a rat model of diabetes-associated cerebral ischemia due to qi and yin deficiency and blood stasis, and to investigate the effects of Radix Ginseng, Rhizoma Chuanxiong, Rhizoma Polygonati Odorati and Rhizoma Polygonati Sibirici Granule (Shenxiong Yujing Granule), which has the function of strengthening qi, nourishing yin, and activating blood, on proliferation, differentiation and survival of neural cells in rats with diabetes-associated cerebral ischemia. METHODS Rats were divided into sham-operation, diabetes plus ischemia reperfusion injury model, Shenxiong Yujing Granule and Radix Ginseng and Rhizoma Chuanxiong Granule (Shenxiong Granule) groups with 20 rats in each. The 5-bromo-2'-deoxyuridine (BrdU) incorporation assay and immunohistochemical method were used to investigate the proliferation, differentiation and survival of neural cells in dentate gyrus of rats with diabetes-associated cerebral ischemia. RESULTS The number of newly proliferating cells in subgranular zone of dentate gyrus was increased in the model group, but there was no significant difference compared with 7 day treatment with Shenxiong Yujing Granule. Shenxiong Yujing Granule significantly increased the survival rate and promoted the differentiation of newly proliferating neurons after 21-day treatment (P<0.01). In addition, the beneficial effect of Shenxiong Yujing Granule was considerably greater than that of the Shenxiong Granule (P<0.01). CONCLUSION Shenxiong Yujing Granule can increase the survival rate and promote the differentiation of newly proliferating neurons in rats with diabetes-associated cerebral ischemia of dual deficiency of qi and yin and blood stasis obstructing the collaterals. The effect is greater than that of Shenxiong Granule.
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Affiliation(s)
- Hui Han
- Department of Neurology, The First Affiliated Hospital, Anhui University of Traditional Chinese Medicine, Hefei 230031, China
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209
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Padovani L, André N, Constine LS, Muracciole X. Neurocognitive function after radiotherapy for paediatric brain tumours. Nat Rev Neurol 2012; 8:578-88. [DOI: 10.1038/nrneurol.2012.182] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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210
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Abstract
The adult brain has long been considered stable and unchanging, except for the inevitable decline that occurs with aqinq. This view is now being challenged with clear evidence that structural changes occur in the brain throughout life, including the generation of new neurons and other brain cells, and connections between and among neurons. What is as remarkable is that the changes that occur in the adult brain are influenced by the behaviors an individual engages in, as well as the environment in which an individual lives, works, and plays. Learning how behavior and environment regulate brain structure and function will lead to strategies to live more effective lives and perhaps protect from, or repair, brain damage and brain disease.
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Affiliation(s)
- Fred H Gage
- Laboratory of Genetics, The Salk Institute, La Jolla, Calif, USA
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211
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Okuyama S, Shimada N, Kaji M, Morita M, Miyoshi K, Minami S, Amakura Y, Yoshimura M, Yoshida T, Watanabe S, Nakajima M, Furukawa Y. Heptamethoxyflavone, a citrus flavonoid, enhances brain-derived neurotrophic factor production and neurogenesis in the hippocampus following cerebral global ischemia in mice. Neurosci Lett 2012; 528:190-5. [PMID: 22985518 DOI: 10.1016/j.neulet.2012.08.079] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 08/22/2012] [Accepted: 08/23/2012] [Indexed: 01/08/2023]
Abstract
In the present study using a transient global ischemia mouse model, we showed that (1) a citrus flavonoid 3,5,6,7,8,3',4'-heptamethoxyflavone (HMF) induced the phosphorylation of extracellular signal-regulated kinases 1/2 (ERK1/2) and cAMP response element-binding protein (CREB) in the hippocampus after ischemia; (2) HMF increased the expression of brain-derived neurotrophic factor (BDNF), a representative neurotrophic factor in the central nervous system, in the hippocampal dentate gyrus, and most BDNF-positive cells were also stained with anti-glial fibrillary acidic protein (one of the major intermediate filament proteins of mature astrocytes) and (3) HMF increased doublecortin positive neuronal precursor cells in the dentate gyrus subventricular zone or subgranular zone. These results suggest that HMF has the ability to induce BDNF production in astrocytes and enhance neurogenesis after brain ischemia, which may be mediated by activation of ERK1/2 and CREB.
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Affiliation(s)
- Satoshi Okuyama
- Department of Pharmaceutical Pharmacology, College of Pharmaceutical Sciences, Matsuyama University, 4-2 Bunkyo-cho, Matsuyama, Ehime 790-8578, Japan.
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212
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Moraes L, Vasconcelos-dos-Santos A, Santana FC, Godoy MA, Rosado-de-Castro PH, Jasmin, Azevedo-Pereira RL, Cintra WM, Gasparetto EL, Santiago MF, Mendez-Otero R. Neuroprotective effects and magnetic resonance imaging of mesenchymal stem cells labeled with SPION in a rat model of Huntington's disease. Stem Cell Res 2012; 9:143-55. [DOI: 10.1016/j.scr.2012.05.005] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 04/26/2012] [Accepted: 05/18/2012] [Indexed: 01/14/2023] Open
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213
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Niv F, Keiner S, Krishna K, Witte OW, Lie DC, Redecker C. Aberrant neurogenesis after stroke: a retroviral cell labeling study. Stroke 2012; 43:2468-75. [PMID: 22738919 DOI: 10.1161/strokeaha.112.660977] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND AND PURPOSE Adult neurogenesis in the dentate gyrus is a unique form of brain plasticity that is strongly stimulated after stroke. We investigate the morphological properties of new granule cells, which are born and develop after the ischemic insult, and query whether these adult-born neurons properly integrate into the pre-existing hippocampal circuitries. METHODS Two well-established models were used to induce either small cortical infarcts (photothrombosis model) or large territorial infarcts (transient middle cerebral artery occlusion model). New granule cells were labeled 4 days after the initial insult by intrahippocampal injection of a retroviral vector encoding green fluorescent protein and newborn neurons were morphologically analyzed using a semiautomatic Neurolucida system and confocal laser scanning microscopy at 6 weeks. RESULTS Approximately 5% to 10% of newborn granule cells displayed significant morphological abnormalities comprising additional basal dendrites and, after middle cerebral artery occlusion, also ectopic cell position. The extent of morphological abnormalities was higher after large territorial infarcts and seems to depend on the severity of ischemic damage. An increased portion of mushroom spines in aberrant neurons suggests stable synaptic integration. However, poststroke generated granule cells with regular appearance also demonstrate alterations in dendritic complexity and spine morphology. CONCLUSIONS The remarkable stimulation of dentate neurogenesis after stroke coincides with an increased rate of aberrantly integrated neurons, which may contribute to functional impairments and, hypothetically, favor pathogenesis of adjustment disorders, cognitive deficits, or epilepsy often seen in stroke patients.
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Affiliation(s)
- Fanny Niv
- Hans Berger Department of Neurology, Jena University Hospital, Erlanger Allee 101, 07747 Jena, Germany
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214
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Prolonged therapeutic hypothermia does not adversely impact neuroplasticity after global ischemia in rats. J Cereb Blood Flow Metab 2012; 32:1525-34. [PMID: 22434072 PMCID: PMC3421089 DOI: 10.1038/jcbfm.2012.38] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Hypothermia improves clinical outcome after cardiac arrest in adults. Animal data show that a day or more of cooling optimally reduces edema and tissue injury after cerebral ischemia, especially after longer intervention delays. Lengthy treatments, however, may inhibit repair processes (e.g., synaptogenesis). Thus, we evaluated whether unilateral brain hypothermia (∼33°C) affects neuroplasticity in the rat 2-vessel occlusion model. In the first experiment, we cooled starting 1 hour after ischemia for 2, 4, or 7 days. Another group was cooled for 2 days starting 48 hours after ischemia. One group remained normothermic throughout. All hypothermia treatments started 1 hour after ischemia equally reduced hippocampal CA1 injury in the cooled hemisphere compared with the normothermic side and the normothermic group. Cooling only on days 3 and 4 was not beneficial. Importantly, no treatment influenced neurogenesis (Ki67/Doublecortin (DCX) staining), synapse formation (synaptophysin), or brain-derived neurotropic factor (BDNF) immunohistochemistry. A second experiment confirmed that BDNF levels (ELISA) were equivalent in normothermic and 7-day cooled rats. Last, we measured zinc (Zn), which is important in plasticity, with X-ray fluorescence imaging in normothermic and 7-day cooled rats. Hypothermia did not alter the postischemic distribution of Zn within the hippocampus. In summary, cooling significantly mitigates injury without compromising neuroplasticity.
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215
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The role of eNSCs in neurodegenerative disease. Mol Neurobiol 2012; 46:555-62. [PMID: 22821143 DOI: 10.1007/s12035-012-8303-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Accepted: 07/09/2012] [Indexed: 01/19/2023]
Abstract
Recent progress in biology has shown that many if not all adult tissues contain a population of stem cells. It is believed that these cells are involved in the regeneration of the tissue or organ in which they reside as a response to the natural turnover of differentiated cells or to injury. In the adult mammalian brain, stem cells in the subventricular zone and the dentate gyrus may also play a role in the replacement of neurons. A positive beneficial response to injury does not necessarily require cell replacement. New findings suggest that some populations of endogenous neural stem cells in the central nervous system may have adopted a function different from cell replacement and are involved in the protection of neurons in diverse paradigms of disease and injury. In this article, we will focus on the immature cell populations of the central nervous system and the signal transduction pathways that regulate them which suggest new possibilities for their manipulation in injury and disease.
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216
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Cognitive effects of NSAIDs in cerebral ischemia: a hypothesis exploring mechanical action mediated pharmacotherapy. Med Hypotheses 2012; 79:393-5. [PMID: 22771072 DOI: 10.1016/j.mehy.2012.06.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Revised: 05/26/2012] [Accepted: 06/03/2012] [Indexed: 12/19/2022]
Abstract
Cerebral ischemia is associated with altered neuronal mechanics leading to dynamic reshaping of neuronal structures, giving rise to a cascade of biological pathways leading to many deleterious consequences and cognitive deficits. Memory and learning specifically are mediated by neurotransmitter release from vesicles clustered at the synapse. Mechanical tension is an important factor governing the amount of vesicular neurotransmitter release in response to an action potential. Neuroinflammation in cerebral ischemia leads to altered mechanical/physical forces on neurons which gives rise to abnormal mechanical tension along the neuron resulting in neurotransmitter imbalance leading to cognitive dysfunction. We consider the possibility that modulation of mechanical forces on neurons may be a therapeutic strategy to help prevent cognitive deficit in cerebral ischemia. Here we show how NSAIDs may act as candidate pharmacological molecules which have the ability to inhibit neuroinflammation and which can alter neuronal mechanics by their COX-2 inhibiting property.
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217
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Ma L, Cui XL, Wang Y, Li XW, Yang F, Wei D, Jiang W. Aspirin attenuates spontaneous recurrent seizures and inhibits hippocampal neuronal loss, mossy fiber sprouting and aberrant neurogenesis following pilocarpine-induced status epilepticus in rats. Brain Res 2012; 1469:103-13. [PMID: 22765917 DOI: 10.1016/j.brainres.2012.05.058] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 05/01/2012] [Accepted: 05/31/2012] [Indexed: 10/28/2022]
Abstract
Accumulating data suggest that inflammation may contribute to epileptogenesis in experimental models as well as in humans. However, whether anti-inflammatory treatments can prevent epileptogenesis still remains controversial. Here, we examined the anti-epileptogenic effect and possible mechanisms of aspirin, a non-selective Cyclooxygenase (COX) inhibitor, in a rat model of lithium-pilocarpine-induced status epilepticus (SE). Epileptic rats were treated with aspirin (20mg/kg) at 0h, 3h, or 24h after the termination of SE, followed by once daily treatment for the subsequent 20 days. We found that aspirin treatment significantly reduced the frequency and duration of spontaneous recurrent seizures during the chronic epileptic phase. Hippocampal neuronal loss five weeks after SE was also attenuated in the CA1, CA3 and hilus following aspirin administration. Furthermore, the aberrant migration of newly generated granule cells and the formation of hilar basal dendrites were prevented by aspirin. Treatment with aspirin starting at 3h or 24h after SE also suppressed the development of mossy fiber sprouting. These findings suggest the possibility of a relative broad time-window for aspirin intervention in the epileptogenic process after injury. Aspirin may serve as a potential adjunctive therapy for individuals susceptible to chronic epilepsy.
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Affiliation(s)
- Lei Ma
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, 17 Changle West Road, Xi'an 710032, China
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218
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Abstract
The importance of adult neurogenesis has only recently been accepted, resulting in a completely new field of investigation within stem cell biology. The regulation and functional significance of adult neurogenesis is currently an area of highly active research. G-protein-coupled receptors (GPCRs) have emerged as potential modulators of adult neurogenesis. GPCRs represent a class of proteins with significant clinical importance, because approximately 30% of all modern therapeutic treatments target these receptors. GPCRs bind to a large class of neurotransmitters and neuromodulators such as norepinephrine, dopamine, and serotonin. Besides their typical role in cellular communication, GPCRs are expressed on adult neural stem cells and their progenitors that relay specific signals to regulate the neurogenic process. This review summarizes the field of adult neurogenesis and its methods and specifies the roles of various GPCRs and their signal transduction pathways that are involved in the regulation of adult neural stem cells and their progenitors. Current evidence supporting adult neurogenesis as a model for self-repair in neuropathologic conditions, adult neural stem cell therapeutic strategies, and potential avenues for GPCR-based therapeutics are also discussed.
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Affiliation(s)
- Van A Doze
- Department of Molecular Cardiology, NB50, Lerner Research Institute, The Cleveland Clinic Foundation, 9500 Euclid Ave., Cleveland, OH 44195, USA
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219
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Wang X, Mao X, Xie L, Sun F, Greenberg DA, Jin K. Conditional depletion of neurogenesis inhibits long-term recovery after experimental stroke in mice. PLoS One 2012; 7:e38932. [PMID: 22723908 PMCID: PMC3378583 DOI: 10.1371/journal.pone.0038932] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Accepted: 05/14/2012] [Indexed: 11/19/2022] Open
Abstract
We reported previously that ablation of doublecortin (DCX)-immunopositive newborn neurons in mice worsens anatomical and functional outcome measured 1 day after experimental stroke, but whether this effect persists is unknown. We generated transgenic mice that express herpes simplex virus thymidine kinase under control of the DCX promoter (DCX-TK transgenic mice). DCX-expressing and recently divided cells in the rostral subventricular zone (SVZ) and hippocampus of DCX-TK transgenic mice, but not wild-type mice, were specifically depleted after ganciclovir (GCV) treatment for 14 days. Focal cerebral ischemia was induced by permanent distal middle cerebral artery occlusion (MCAO) on day 14 of vehicle or GCV treatment, and mice were killed 12 weeks after MCAO. Infarct volume was significantly increased and neurologic deficits were more severe in GCV- compared to vehicle-treated DCX-TK transgenic mice at first 8 weeks, after depletion of DCX- and bromodeoxyuridine-immunoreactive cells in the SVZ and dentate gyrus following focal ischemia. Our results indicate that endogenous neurogenesis in a critical period following experimental stroke influences the course of long-term recovery.
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Affiliation(s)
- Xiaomei Wang
- Buck Institute for Research on Aging, Novato, California, United States of America
| | - XiaoOu Mao
- Buck Institute for Research on Aging, Novato, California, United States of America
| | - Lin Xie
- Buck Institute for Research on Aging, Novato, California, United States of America
| | - Fen Sun
- Buck Institute for Research on Aging, Novato, California, United States of America
| | - David A. Greenberg
- Buck Institute for Research on Aging, Novato, California, United States of America
| | - Kunlin Jin
- Buck Institute for Research on Aging, Novato, California, United States of America
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center at Fort Worth, Fort Worth, Texas, United States of America
- Institute for Aging and Alzheimer’s Disease Research, University of North Texas Health Science Center at Fort Worth, Fort Worth, Texas, United States of America
- * E-mail:
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Rueger MA, Muesken S, Walberer M, Jantzen SU, Schnakenburg K, Backes H, Graf R, Neumaier B, Hoehn M, Fink GR, Schroeter M. Effects of minocycline on endogenous neural stem cells after experimental stroke. Neuroscience 2012; 215:174-83. [PMID: 22542871 DOI: 10.1016/j.neuroscience.2012.04.036] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 04/13/2012] [Indexed: 01/09/2023]
Abstract
Minocycline has been reported to reduce infarct size after focal cerebral ischemia, due to an attenuation of microglia activation and prevention of secondary damage from stroke-induced neuroinflammation. We here investigated the effects of minocycline on endogenous neural stem cells (NSCs) in vitro and in a rat stroke model. Primary cultures of fetal rat NSCs were exposed to minocycline to characterize its effects on cell survival and proliferation. To assess these effects in vivo, permanent cerebral ischemia was induced in adult rats, treated systemically with minocycline or placebo. Imaging 7 days after ischemia comprised (i) Magnetic Resonance Imaging (MRI), assessing the extent of infarcts, (ii) Positron Emission Tomography (PET) with [(11)C]PK11195, characterizing neuroinflammation, and (iii) PET with 3'-deoxy-3'-[(18)F]fluoro-L-thymidine ([(18)F]FLT), detecting proliferating endogenous NSCs. Immunohistochemistry was used to verify ischemic damage and characterize cellular inflammatory and repair processes in more detail. In vitro, specific concentrations of minocycline significantly increased NSC numbers without increasing their proliferation, indicating a positive effect of minocycline on NSC survival. In vivo, endogenous NSC activation in the subventricular zone (SVZ) measured by [(18)F]FLT PET correlated well with infarct volumes. Similar to in vitro findings, minocycline led to a specific increase in endogenous NSC activity in both the SVZ as well as the hippocampus. [(11)C]PK11195 PET detected neuroinflammation in the infarct core as well as in peri-infarct regions, with both its extent and location independent of the infarct size. The data did not reveal an effect of minocycline on stroke-induced neuroinflammation. We show that multimodal PET imaging can be used to characterize and quantify complex cellular processes occurring after stroke, as well as their modulation by therapeutic agents. We found minocycline, previously implied in attenuating microglial activation, to have positive effects on endogenous NSC survival. These findings hold promise for the development of novel treatments in stroke therapy.
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Affiliation(s)
- M A Rueger
- Department of Neurology, University Hospital of Cologne, Germany.
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221
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Liu DZ, Ander BP. Cell cycle inhibition without disruption of neurogenesis is a strategy for treatment of aberrant cell cycle diseases: an update. ScientificWorldJournal 2012; 2012:491737. [PMID: 22547985 PMCID: PMC3323905 DOI: 10.1100/2012/491737] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Accepted: 11/17/2011] [Indexed: 12/12/2022] Open
Abstract
Since publishing our earlier report describing a strategy for the treatment of central nervous system (CNS) diseases by inhibiting the cell cycle and without disrupting neurogenesis (Liu et al. 2010), we now update and extend this strategy to applications in the treatment of cancers as well. Here, we put forth the concept of "aberrant cell cycle diseases" to include both cancer and CNS diseases, the two unrelated disease types on the surface, by focusing on a common mechanism in each aberrant cell cycle reentry. In this paper, we also summarize the pharmacological approaches that interfere with classical cell cycle molecules and mitogenic pathways to block the cell cycle of tumor cells (in treatment of cancer) as well as to block the cell cycle of neurons (in treatment of CNS diseases). Since cell cycle inhibition can also block proliferation of neural progenitor cells (NPCs) and thus impair brain neurogenesis leading to cognitive deficits, we propose that future strategies aimed at cell cycle inhibition in treatment of aberrant cell cycle diseases (i.e., cancers or CNS diseases) should be designed with consideration of the important side effects on normal neurogenesis and cognition.
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Affiliation(s)
- Da-Zhi Liu
- Department of Neurology and the MIND Institute, University of California at Davis, Sacramento, CA 95817, USA.
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222
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Excitatory and Mitogenic Signaling in Cell Death, Blood-brain Barrier Breakdown, and BBB Repair after Intracerebral Hemorrhage. Transl Stroke Res 2012; 3:62-9. [PMID: 24323862 DOI: 10.1007/s12975-012-0147-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2012] [Revised: 02/18/2012] [Accepted: 02/22/2012] [Indexed: 02/06/2023]
Abstract
Intracerebral hemorrhage (ICH) results in the release of a large number of endogenous molecules, including glutamate, Ca(2+), ROS, thrombin, heme, iron, TNF-α, and others. These molecules participate in excitatory and mitogenic signaling transduction in which N-methyl-D-aspartate (NMDA) receptors and Src family kinases (SFKs) are implicated. Mitogenic signaling initiates the cell cycle for normal cell division of microglia and neural progenitor cells, whereas aberrant mitogenic signaling causes toxicity, killing neurons, astrocytes, and brain microvascular endothelial cells in neurological diseases including ICH. In this review, we summarize (1) how SFKs modulate NMDA receptors to kill neurons following ICH and (2) how SFKs modulate mitogenic signaling transduction to kill neurons and play a role in disrupting the blood-brain barrier (BBB) immediately following ICH and in repairing the BBB during the recovery phases weeks following ICH.
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223
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d'Avila JC, Lam TI, Bingham D, Shi J, Won SJ, Kauppinen TM, Massa S, Liu J, Swanson RA. Microglial activation induced by brain trauma is suppressed by post-injury treatment with a PARP inhibitor. J Neuroinflammation 2012; 9:31. [PMID: 22335939 PMCID: PMC3298794 DOI: 10.1186/1742-2094-9-31] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Accepted: 02/15/2012] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Traumatic brain injury (TBI) induces activation of microglia. Activated microglia can in turn increase secondary injury and impair recovery. This innate immune response requires hours to days to become fully manifest, thus providing a clinically relevant window of opportunity for therapeutic intervention. Microglial activation is regulated in part by poly(ADP-ribose) polymerase-1 (PARP-1). Inhibition of PARP-1 activity suppresses NF-kB-dependent gene transcription and thereby blocks several aspects of microglial activation. Here we evaluated the efficacy of a PARP inhibitor, INO-1001, in suppressing microglial activation after cortical impact in the rat. METHODS Rats were subjected to controlled cortical impact and subsequently treated with 10 mg/kg of INO-1001 (or vehicle alone) beginning 20 - 24 hours after the TBI. Brains were harvested at several time points for histological evaluation of inflammation and neuronal survival, using markers for microglial activation (morphology and CD11b expression), astrocyte activation (GFAP), and neuronal survival (NeuN). Rats were also evaluated at 8 weeks after TBI using measures of forelimb dexterity: the sticky tape test, cylinder test, and vermicelli test. RESULTS Peak microglial and astrocyte activation was observed 5 to 7 days after this injury. INO-1001 significantly reduced microglial activation in the peri-lesion cortex and ipsilateral hippocampus. No rebound inflammation was observed in rats that were treated with INO-1001 or vehicle for 12 days followed by 4 days without drug. The reduced inflammation was associated with increased neuronal survival in the peri-lesion cortex and improved performance on tests of forelimb dexterity conducted 8 weeks after TBI. CONCLUSIONS Treatment with a PARP inhibitor for 12 days after TBI, with the first dose given as long as 20 hours after injury, can reduce inflammation and improve histological and functional outcomes.
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Affiliation(s)
- Joana C d'Avila
- Dept. of Neurology, Veterans Affairs Medical Center, San Francisco, California 94121, USA
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224
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Malone CD, Hasan SMM, Roome RB, Xiong J, Furlong M, Opferman JT, Vanderluit JL. Mcl-1 regulates the survival of adult neural precursor cells. Mol Cell Neurosci 2012; 49:439-47. [PMID: 22357134 DOI: 10.1016/j.mcn.2012.02.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Revised: 01/19/2012] [Accepted: 02/06/2012] [Indexed: 10/28/2022] Open
Abstract
Since the discovery of neural precursor cells (NPCs) in the adult mammalian brain, there has been a lot of excitement surrounding the potential for regeneration in the adult brain. For instance, many studies have shown that a significant number of NPCs will migrate to a site of injury and differentiate into all of the neural lineages. However, one of the main challenges affecting endogenous neural regeneration is that many of the NPCs that migrate to the injury site ultimately undergo apoptosis. Therefore, we sought to determine whether myeloid cell leukemia-1 (Mcl-1), an anti-apoptotic Bcl-2 protein, would promote the survival of adult NPCs by impeding apoptosis. To do this, we first confirmed that Mcl-1 is endogenously expressed within the adult NPC population using BrdU labeling assays. Next, we conditionally deleted Mcl-1 in adult NPCs using cre/lox technology and expressed Cre from the NPC-specific promoter Nestin. In vitro, cells that had Mcl-1 conditionally deleted had a 2-fold increase in apoptosis when compared to controls. In vivo, we used electroporation to conditionally delete Mcl-1 in adult NPCs and assessed apoptosis at 72h. after electroporation. As in our in vitro results, there was a 2-fold increase in apoptosis when Mcl-1 was conditionally deleted. Finally, we found that Mcl-1 over-expression reduced the endogenous rate of adult NPC apoptosis 2-fold in vitro. Collectively, these results demonstrate that Mcl-1 is crucial for the survival of adult NPCs and may be a promising target for future neural regeneration therapies.
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Affiliation(s)
- Craig D Malone
- Division of BioMedical Sciences, Memorial University of Newfoundland, St. John's, NL, Canada, A1B 3V6
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225
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Pérez-Gómez A, Tasker RA. Enhanced neurogenesis in organotypic cultures of rat hippocampus after transient subfield-selective excitotoxic insult induced by domoic acid. Neuroscience 2012; 208:97-108. [PMID: 22366222 DOI: 10.1016/j.neuroscience.2012.02.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Revised: 01/27/2012] [Accepted: 02/01/2012] [Indexed: 01/19/2023]
Abstract
New neurons are continuously generated in the hippocampus and may play an important role in many physiological and pathological conditions. Here we present evidence of cell proliferation and neurogenesis after a selective and transient excitotoxic injury to the hippocampal cornu ammonis 1 (CA1) area induced by low concentrations of domoic acid (DOM) in rat organotypic hippocampal slice cultures (OHSC). DOM is an excitatory amino acid analog to kainic acid that acts through glutamate receptors to elicit a rapid and potent excitotoxic response. Exposure of slice cultures to varying concentrations of DOM for 24 h induced dose-dependent neuronal toxicity that was independent of activation of classic apoptotic markers. Treatment with 2 μM DOM for 24 h caused a selective yet transient neurotoxic injury in the CA1 subfield of the hippocampus that appeared recovered after 7 days of incubation in a DOM-free medium and showed significant microgliosis but no sign of astrogliosis. The DOM insult (2 μM, 24 h) resulted in a significant upregulation of cell proliferation, as assessed by 5-bromo-2-deoxyuridine (BrdU) incorporation, and a concurrent increase of the neuronal precursor cell marker doublecortin (DCX) within the subgranular zone of the dentate gyrus and area CA1. Neurogenesis occurred primarily during the first week after termination of the DOM exposure. Our study shows that exposure of OHSC to concentrations of DOM below those required to induce permanent neurotoxicity can induce proliferation and differentiation of neural progenitor cells that may contribute to recovery from mild injury and to develop abnormal circuits relevant to disease.
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Affiliation(s)
- A Pérez-Gómez
- Department of Biomedical Sciences, University of Prince Edward Island, Charlottetown, PEI, Canada
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226
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Dayan K, Keser A, Konyalioglu S, Erturk M, Aydin F, Sengul G, Dagci T. The effect of hyperbaric oxygen on neuroregeneration following acute thoracic spinal cord injury. Life Sci 2012; 90:360-4. [DOI: 10.1016/j.lfs.2011.12.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 11/19/2011] [Accepted: 12/14/2011] [Indexed: 01/27/2023]
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227
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Romero-Grimaldi C, Murillo-Carretero M, López-Toledano MA, Carrasco M, Castro C, Estrada C. ADAM-17/tumor necrosis factor-α-converting enzyme inhibits neurogenesis and promotes gliogenesis from neural stem cells. Stem Cells 2012; 29:1628-39. [PMID: 21837653 DOI: 10.1002/stem.710] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Neural precursor cells (NPCs) are activated in central nervous system injury. However, despite being multipotential, their progeny differentiates into astrocytes rather than neurons in situ. We have investigated the role of epidermal growth factor receptor (EGFR) in the generation of non-neurogenic conditions. Cultured mouse subventricular zone NPCs exposed to differentiating conditions for 4 days generated approximately 50% astrocytes and 30% neuroblasts. Inhibition of EGFR with 4-(3-chloroanilino)-6,7-dimethoxyquinazoline significantly increased the number of neuroblasts and decreased that of astrocytes. The same effects were observed upon treatment with the metalloprotease inhibitor galardin, N-[(2R)-2-(hydroxamidocarbonylmethyl)-4-methylpentanoyl]-L-tryptophan methylamide (GM 6001), which prevented endogenous transforming growth factor-α (TGF-α) release. These results suggested that metalloprotease-dependent EGFR-ligand shedding maintained EGFR activation and favored gliogenesis over neurogenesis. Using a disintegrin and metalloprotease 17 (ADAM-17) small interference RNAs transfection of NPCs, ADAM-17 was identified as the metalloprotease involved in cell differentiation in these cultures. In vivo experiments revealed a significant upregulation of ADAM-17 mRNA and de novo expression of ADAM-17 protein in areas of cortical injury in adult mice. Local NPCs, identified by nestin staining, expressed high levels of ADAM-17, as well as TGF-α and EGFR, the three molecules necessary to prevent neurogenesis and promote glial differentiation in vitro. Chronic local infusions of GM6001 resulted in a notable increase in the number of neuroblasts around the lesion. These results indicate that, in vivo, the activation of a metalloprotease, most probably ADAM-17, initiates EGFR-ligand shedding and EGFR activation in an autocrine manner, preventing the generation of new neurons from NPCs. Inhibition of ADAM-17, the limiting step in this sequence, may contribute to the generation of neurogenic niches in areas of brain damage.
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228
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Choi JH, Yoo KY, Lee CH, Park JH, Yan BC, Kwon SH, Seo JY, Cho JH, Hwang IK, Won MH. Comparison of neurogenesis in the dentate gyrus between the adult and aged gerbil following transient global cerebral ischemia. Neurochem Res 2012; 37:802-10. [PMID: 22215251 DOI: 10.1007/s11064-011-0675-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Revised: 12/04/2011] [Accepted: 12/15/2011] [Indexed: 01/02/2023]
Abstract
In the present study, we compared differences in cell proliferation, neuroblast differentiation and neuronal maturation in the hippocampal dentate gyrus (DG) between the adult and aged gerbil induced by 5 min of transient global cerebral ischemia using Ki-67 and BrdU (markers for cell proliferation), doublecortin (DCX, a marker for neuroblast differentiation) and neuronal nuclei (NeuN, a marker for mature neuron). The number of Ki-67-immunoreactive (⁺) cells in the DG of both the groups peaked 7 days after ischemia/reperfusion (I/R). However, the number in the aged DG was 40.6 ± 1.8% of that in the adult DG. Thereafter, the number decreased with time. After ischemic damage, DCX immunoreactivity and its protein level in the adult and aged DG peaked at 10 and 15 days post-ischemia, respectively. However, DCX immunoreactivity and its protein levels in the aged DG were much lower than those in the adult. DCX immunoreactivity and its protein level in the aged DG were 11.1 ± 0.6% and 34.4 ± 2.1% of the adult DG, respectively. In addition, the number of Ki-67⁺ cells and DCX immunoreactivity in both groups were similar to those in the sham at 60 days postischemia. At 30 days post-ischemia, the number of BrdU⁺ cells and BrdU⁺/NeuN⁺ cells in the adult-group were much higher (281.2 ± 23.4% and 126.4 ± 7.4%, respectively) than the aged-group (35.6 ± 6.8% and 79.5 ± 6.1%, respectively). These results suggest that the ability of neurogenesis in the ischemic aged DG is much lower than that in the ischemic adult DG.
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Affiliation(s)
- Jung Hoon Choi
- Department of Anatomy, College of Veterinary Medicine, Kangwon National University, Chuncheon 200-701, South Korea
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Bregy A, Nixon R, Lotocki G, Alonso OF, Atkins CM, Tsoulfas P, Bramlett HM, Dietrich WD. Posttraumatic hypothermia increases doublecortin expressing neurons in the dentate gyrus after traumatic brain injury in the rat. Exp Neurol 2011; 233:821-8. [PMID: 22197046 DOI: 10.1016/j.expneurol.2011.12.008] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Revised: 11/30/2011] [Accepted: 12/05/2011] [Indexed: 12/12/2022]
Abstract
Previous studies have demonstrated that moderate hypothermia reduces histopathological damage and improves behavioral outcome after experimental traumatic brain injury (TBI). Further investigations have clarified the mechanisms underlying the beneficial effects of hypothermia by showing that cooling reduces multiple cell injury cascades. The purpose of this study was to determine whether hypothermia could also enhance endogenous reparative processes following TBI such as neurogenesis and the replacement of lost neurons. Male Sprague-Dawley rats underwent moderate fluid-percussion brain injury and then were randomized into normothermia (37°C) or hypothermia (33°C) treatment. Animals received injections of 5-bromo-2'-deoxyuridine (BrdU) to detect mitotic cells after brain injury. After 3 or 7 days, animals were perfusion-fixed and processed for immunocytochemistry and confocal analysis. Sections were stained for markers selective for cell proliferation (BrdU), neuroblasts and immature neurons (doublecortin), and mature neurons (NeuN) and then analyzed using non-biased stereology to quantify neurogenesis in the dentate gyrus (DG). At 7 days after TBI, both normothermic and hypothermic TBI animals demonstrated a significant increase in the number of BrdU-immunoreactive cells in the DG as compared to sham-operated controls. At 7 days post-injury, hypothermia animals had a greater number of BrdU (ipsilateral cortex) and doublecortin (ipsilateral and contralateral cortex) immunoreactive cells in the DG as compared to normothermia animals. Because adult neurogenesis following injury may be associated with enhanced functional recovery, these data demonstrate that therapeutic hypothermia sustains the increase in neurogenesis induced by TBI and this may be one of the mechanisms by which hypothermia promotes reparative strategies in the injured nervous system.
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Affiliation(s)
- Amade Bregy
- Department of Neurological Surgery, The Neurotrauma Research Center, The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL 33136, USA
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Ko IG, Cho H, Kim SE, Kim JE, Sung YH, Kim BK, Shin MS, Cho S, Pak YK, Kim CJ. Hypothermia alleviates hypoxic ischemia-induced dopamine dysfunction and memory impairment in rats. Anim Cells Syst (Seoul) 2011. [DOI: 10.1080/19768354.2011.607514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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Ekonomou A, Ballard CG, Pathmanaban ON, Perry RH, Perry EK, Kalaria RN, Minger SL. Increased neural progenitors in vascular dementia. Neurobiol Aging 2011; 32:2152-61. [DOI: 10.1016/j.neurobiolaging.2010.01.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Revised: 12/02/2009] [Accepted: 01/14/2010] [Indexed: 10/19/2022]
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233
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Kim MS, Park HR, Chung HY, Kim HS, Yu BP, Yang HS, Lee J. Organic solvent metabolite, 1,2-diacetylbenzene, impairs neural progenitor cells and hippocampal neurogenesis. Chem Biol Interact 2011; 194:139-47. [PMID: 22020177 DOI: 10.1016/j.cbi.2011.10.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 09/20/2011] [Accepted: 10/03/2011] [Indexed: 01/16/2023]
Abstract
1,2-Diacetylbenzene (DAB) is a neurotoxic minor metabolite of 1,2-diethylbenzene or naphthalene reaction product with OH radical. DAB causes central and peripheral neuropathies that lead to motor neuronal deficits. However, the potent effects and molecular mechanisms of DAB on neural progenitor cells and hippocampus are unknown. In the current study, we report the DAB damage at lower doses (less than 50 μM) to neural progenitor cell (NPC) invitro and hippocampal neurogenesis invivo. DAB significantly suppressed NPC proliferation with increased reactive oxygen species (ROS) production in a dose-dependent manner. The suppression of NPC proliferation was effectively blunted by the action of an antioxidant, N-acetyl cysteine. Six-week-old male C57BL/6 mice were treated with 1 or 5 mg/kg DAB for 2 weeks. DAB significantly suppressed NPC proliferation in the dentate gyrus of the hippocampus, indicating impaired hippocampal neurogenesis. Increased ROS production and the formation of oxidative stress-associated dinitrophenyl adducts were detected in the hippocampal homogenates of DAB-treated mice. DAB activated Mac-1-positive immune cells which are involved in inflammatory process in the hippocampus. Taken together, these results confirm that oxidative stress by DAB might be cause of adverse effects in NPC proliferation and hippocampal neurogenesis.
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Affiliation(s)
- Min-Sun Kim
- Department of Pharmacy, College of Pharmacy and Research Institute for Drug Development, Pusan National University, Geumjeong-gu, Busan, Republic of Korea
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234
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Sun X, Zhang QW, Xu M, Guo JJ, Shen SW, Wang YQ, Sun FY. New striatal neurons form projections to substantia nigra in adult rat brain after stroke. Neurobiol Dis 2011; 45:601-9. [PMID: 22005319 DOI: 10.1016/j.nbd.2011.09.018] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 09/11/2011] [Accepted: 09/30/2011] [Indexed: 01/19/2023] Open
Abstract
Previous studies have demonstrated that newborn striatal neurons can functionally integrate with local neural networks in adult rat brain after injury. In the present study, we determined whether these newly generated striatal neurons can develop projections to the substantia nigra, a target of striatal projection neurons. We used 5'-bromodeoxyuridine (BrdU) and a retroviral vector expressing green fluorescent protein (GFP) combined with multiple immunostaining labels of newborn striatal neurons, and nigral microinjection of fluorogold (FG) to trace the striatonigral projection in adult rat brain at different weeks following a transient middle cerebral artery occlusion (MCAO). We found that FG positive (FG(+)) cells could be detected in newly generated neurons (BrdU(+)-NeuN(+) and GFP(+)-NeuN(+)) in ipsilateral striatum clearly at 12, but not 2 weeks after MCAO. The data suggest that ischemia-induced newborn striatal projection neurons could form long axons that targeted the substantia nigra (striatonigral projection pathway) and that have intact axonal transport from the nerve terminal to cell body. These new striatal neurons express glutamate NR2 and dopamine D2L receptors, which form the molecular basis for responding to the inputs from cortical glutamatergic and nigral dopaminergic projection neurons. Our data provide the first morphological evidence that newborn neurons in the striatum, a non-neurogenic region, can establish new striatonigral neural circuits, important pathways for the maintenance of motor function. These results help us to understand endogenous cellular mechanisms of brain repair, and suggest that increasing adult neurogenesis could be a practical strategy for enhancing the efficacy of rehabilitative therapy in stroke patients.
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Affiliation(s)
- Xiao Sun
- Department of Neurobiology and State Key Laboratory of Medical Neurobiology, Shanghai Medical College of Fudan University, Shanghai 200032, PR China
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235
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Doeppner TR, Bretschneider E, Doehring M, Segura I, Sentürk A, Acker-Palmer A, Hasan MR, ElAli A, Hermann DM, Bähr M. Enhancement of endogenous neurogenesis in ephrin-B3 deficient mice after transient focal cerebral ischemia. Acta Neuropathol 2011; 122:429-42. [PMID: 21779764 PMCID: PMC3291816 DOI: 10.1007/s00401-011-0856-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Revised: 07/01/2011] [Accepted: 07/02/2011] [Indexed: 01/26/2023]
Abstract
Cerebral ischemia stimulates endogenous neurogenesis. However, the functional relevance of this phenomenon remains unclear because of poor survival and low neuronal differentiation rates of newborn cells. Therefore, further studies on mechanisms regulating neurogenesis under ischemic conditions are required, among which ephrin-ligands and ephrin-receptors (Eph) are an interesting target. Although Eph/ephrin proteins like ephrin-B3 are known to negatively regulate neurogenesis under physiological conditions, their role in cerebral ischemia is largely unknown. We therefore studied neurogenesis, brain injury and functional outcome in ephrin-B3−/− (knockout) and ephrin-B3+/+ (wild-type) mice submitted to cerebral ischemia. Induction of stroke resulted in enhanced cell proliferation and neuronal differentiation around the lesion site of ephrin-B3−/− compared to ephrin-B3+/+ mice. However, prominent post-ischemic neurogenesis in ephrin-B3−/− mice was accompanied by significantly increased ischemic injury and motor coordination deficits that persisted up to 4 weeks. Ischemic injury in ephrin-B3−/− mice was associated with a caspase-3-dependent activation of the signal transducer and activator of transcription 1 (STAT1). Whereas inhibition of caspase-3 had no effect on brain injury in ephrin-B3+/+ animals, infarct size in ephrin-B3−/− mice was strongly reduced, suggesting that aggravated brain injury in these animals might involve a caspase-3-dependent activation of STAT1. In conclusion, post-ischemic neurogenesis in ephrin-B3−/− mice is strongly enhanced, but fails to contribute to functional recovery because of caspase-3-mediated aggravation of ischemic injury in these animals. Our results suggest that ephrin-B3 might be an interesting target for overcoming some of the limitations of further cell-based therapies in stroke.
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Affiliation(s)
- Thorsten R Doeppner
- Department of Neurology, University of Duisburg-Essen Medical School, Hufelandstr. 55, 45122, Essen, Germany.
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Giuliani D, Zaffe D, Ottani A, Spaccapelo L, Galantucci M, Minutoli L, Bitto A, Irrera N, Contri M, Altavilla D, Botticelli AR, Squadrito F, Guarini S. Treatment of cerebral ischemia with melanocortins acting at MC4 receptors induces marked neurogenesis and long-lasting functional recovery. Acta Neuropathol 2011; 122:443-53. [PMID: 21927944 DOI: 10.1007/s00401-011-0873-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Revised: 09/08/2011] [Accepted: 09/08/2011] [Indexed: 11/29/2022]
Abstract
Melanocortins produce neuroprotection against ischemic stroke with subsequent long-lasting functional recovery, through melanocortin MC(4) receptor activation. Here we investigated whether the long-lasting beneficial effect of melanocortins in stroke conditions is associated with a stimulation of neurogenesis. Gerbils were subjected to transient global cerebral ischemia by occluding both common carotid arteries for 10 min; then, they were prepared for 5-bromo-2'-deoxyuridine (BrdU) labeling of proliferating cells. Delayed treatment (up to 9 h after the ischemic injury) for 11 days with the melanocortin analog [Nle(4),D-Phe(7)]α-melanocyte-stimulating hormone (NDP-α-MSH) improved learning and memory throughout the 50-day observation period. Immunohistochemical examination of the hippocampus on day 50 showed, in the dentate gyrus, an elevated number of BrdU immunoreactive cells colocalized with NeuN (used as indicator of mature neurons) and Zif268 (used as indicator of functionally integrated neurons). Retrospective analysis during the early stage of neural stem/progenitor cell development (days 3 and 4 after stroke) showed, in NDP-α-MSH-treated gerbils, a high degree of daily cell proliferation and revealed that NDP-α-MSH favorably affects Wnt-3A signaling pathways and doublecortin expression. Pharmacologic blockade of MC(4) receptors prevented all effects of NDP-α-MSH. These data indicate that treatment of cerebral ischemia with MC(4) receptor agonists induces, with a broad window of therapeutic opportunity, long-lasting functional recovery associated with a large number of mature and likely functional newborn neurons in brain injured areas. Our findings reveal previously undescribed effects of melanocortins which might have major clinical implications.
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Affiliation(s)
- Daniela Giuliani
- Department of Biomedical Sciences, Section of Pharmacology, University of Modena and Reggio Emilia, Via G. Campi 287, 41125, Modena, Italy
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Otero L, Zurita M, Bonilla C, Aguayo C, Rico MA, Rodríguez A, Vaquero J. Allogeneic bone marrow stromal cell transplantation after cerebral hemorrhage achieves cell transdifferentiation and modulates endogenous neurogenesis. Cytotherapy 2011; 14:34-44. [PMID: 21942842 DOI: 10.3109/14653249.2011.608349] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND AIMS When a severe neurologic lesion occurs as a consequence of intracerebral hemorrhage (ICH), there is no effective treatment available for improving the outcome. However, cell therapy has opened new perspectives on reducing neurologic sequels subsequent to this disease. METHODS In this study, ICH was induced by stereotactic injection of 0.5 U collagenase type IV in the striatum of adult Wistar rats, and 2 h later a group of animals (n = 48) was subjected to intracerebral injection of 2 × 10(6) allogeneic bone marrow stromal cells (BMSC), while a control group (n = 48) received saline only. Eight animals from each group were killed at 48 h, 72 h, 7 days, 14 days, 21 days and 28 days. At these time-points, endogenous neurogenesis and survival of transplanted BMSC were studied. RESULTS Our findings show that after allogeneic BMSC transplantation, donor cells can survive in the brain tissue expressing neuronal and astroglial markers. Furthermore, BMSC transplantation enhances endogenous neurogenesis and inhibits apoptosis of newborn neural cells. CONCLUSIONS Although these results should be extrapolated to human disease with caution, it is obvious that cell therapy using allogeneic BMSC transplantation offers great promise for developing novel and efficacious strategies in patients suffering ICH.
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Affiliation(s)
- Laura Otero
- Neuroscience Research Unit and Service of Neurosurgery, Hospital Puerta de Hierro-Majadahonda, Madrid, Spain
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238
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Spaccapelo L, Bitto A, Galantucci M, Ottani A, Irrera N, Minutoli L, Altavilla D, Novellino E, Grieco P, Zaffe D, Squadrito F, Giuliani D, Guarini S. Melanocortin MC₄ receptor agonists counteract late inflammatory and apoptotic responses and improve neuronal functionality after cerebral ischemia. Eur J Pharmacol 2011; 670:479-86. [PMID: 21946115 DOI: 10.1016/j.ejphar.2011.09.015] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Revised: 08/29/2011] [Accepted: 09/07/2011] [Indexed: 01/30/2023]
Abstract
Indirect evidence indicates that, in cerebral ischemia, melanocortins have neuroprotective effects likely mediated by MC₄ receptors. To gain direct insight into the role of melanocortin MC₄ receptors in ischemic stroke, we investigated the effects of a highly selective MC₄ receptor agonist. Gerbils were subjected to transient global cerebral ischemia by occluding both common carotid arteries for 10 min. In saline-treated stroke animals, an impairment in learning and memory occurred that, at day 11 after stroke, was associated with hippocampus up-regulation of tumor necrosis factor-α (TNF-α), BAX, activated extracellular signal-regulated kinases (ERK1/2), c-jun N-terminal kinases (JNK1/2) and caspase-3, down-regulation of Bcl-2, and neuronal loss. Treatment for 11days with the selective melanocortin MC₄ receptor agonist RO27-3225, as well as with the well known non-selective [Nle⁴,D-Phe⁷]α-melanocyte-stimulating hormone (NDP-α-MSH) as a reference non-selective melanocortin, counteracted the inflammatory and apoptotic responses, as indicated by the changes in TNF-α, BAX, ERK1/2, JNK1/2, caspase-3 and Bcl-2 protein expression. Furthermore, melanocortin treatment reduced neuronal loss and dose-dependently improved learning and memory. These positive effects were associated with overexpression of Zif268, an immediate early gene involved in injury repair, synaptic plasticity and memory formation. Pharmacological blockade of MC₄ receptors with the selective MC₄ receptor antagonist HS024 prevented all effects of RO27-3225 and NDP-α-MSH. These data give direct evidence that stimulation of MC₄ receptors affords neuroprotection and promotes functional recovery from stroke, by counteracting prolonged and/or recurrent inflammatory and apoptotic responses, and likely by triggering brain repair pathways.
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Affiliation(s)
- Luca Spaccapelo
- Department of Biomedical Sciences, Section of Pharmacology, University of Modena and Reggio Emilia, Via G. Campi 287, 41125, Modena, Italy
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239
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Voloboueva LA, Giffard RG. Inflammation, mitochondria, and the inhibition of adult neurogenesis. J Neurosci Res 2011; 89:1989-96. [PMID: 21910136 DOI: 10.1002/jnr.22768] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 07/19/2011] [Accepted: 07/22/2011] [Indexed: 11/12/2022]
Abstract
The process of neurogenesis continues throughout life, with thousands of new neurons generated every day in the mammalian brain. Impairment of hippocampal neurogenesis has been suggested to be involved in neurodegenerative conditions, including the cognitive decline associated with aging, Alzheimer's disease, Parkinson's disease, and ionizing radiation. These neurodegenerative conditions are all characterized by proinflammatory changes and increased numbers of activated microglia. Activated microglia produce a variety of proinflammatory factors, including interleukin-6, tumor necrosis factor-α, reactive oxygen species, and nitric oxide, all of which are antineurogenic. These same factors have also been shown to suppress mitochondrial function, but the role of mitochondria in neurogenesis remains barely investigated. This brief review summarizes the findings of several studies that support a role for mitochondrial impairment as part of the mechanism of the reduction of neurogenesis associated with inflammation.
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Affiliation(s)
- Ludmila A Voloboueva
- Department of Anesthesia, Stanford University School of Medicine, Stanford, California 94305, USA
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240
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Lagace DC. Does the endogenous neurogenic response alter behavioral recovery following stroke? Behav Brain Res 2011; 227:426-32. [PMID: 21907736 DOI: 10.1016/j.bbr.2011.08.045] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2011] [Revised: 08/26/2011] [Accepted: 08/29/2011] [Indexed: 12/22/2022]
Abstract
In response to stroke, the adult brain has the remarkable ability to enhance the proliferation of new cells, which form new neurons in restricted regions. This review focuses on studies that have directly tested the hypothesis that neurogenesis contributes to post-stroke behavioral recovery. The translational potential of this area of research is critically assessed with respect to the selection of appropriate stroke models, subjects, neurogenic regions examined, behavioral tests used, and experimental timecourse. Building upon those studies that suggest an association between endogeneous neurogenesis and improved stroke recovery, we are nonetheless left with the challenge to demonstrate a causal link between neurogenesis and behavioral recovery using new technology.
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Affiliation(s)
- Diane C Lagace
- Department of Cellular and Molecular Medicine, University of Ottawa, Ontario, Canada.
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241
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Lipsanen A, Jolkkonen J. Experimental approaches to study functional recovery following cerebral ischemia. Cell Mol Life Sci 2011; 68:3007-17. [PMID: 21626271 PMCID: PMC11114796 DOI: 10.1007/s00018-011-0733-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Revised: 05/10/2011] [Accepted: 05/12/2011] [Indexed: 01/10/2023]
Abstract
Valid experimental models and behavioral tests are indispensable for the development of therapies for stroke. The translational failure with neuroprotective drugs has forced us to look for alternative approaches. Restorative therapies aiming to facilitate the recovery process by pharmacotherapy or cell-based therapy have emerged as promising options. Here we describe the most common stroke models used in cell-based therapy studies with particular emphasis on their inherent complications, which may affect behavioral outcome. Loss of body weight, stress, hyperthermia, immunodepression, and infections particularly after severe transient middle cerebral artery occlusion (filament model) are recognized as possible confounders to impair performance in certain behavioral tasks and bias the treatment effects. Inherent limitations of stroke models should be carefully considered when planning experiments to ensure translation of behavioral data to the clinic.
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Affiliation(s)
- Anu Lipsanen
- Institute of Clinical Medicine - Neurology, University of Eastern Finland, Yliopistonranta 1C, FI-70210 Kuopio, Finland
- Brain Research and Rehabilitation Center Neuron, Kortejoki, FI-71130 Kuopio, Finland
| | - Jukka Jolkkonen
- Institute of Clinical Medicine - Neurology, University of Eastern Finland, Yliopistonranta 1C, FI-70210 Kuopio, Finland
- Brain Research and Rehabilitation Center Neuron, Kortejoki, FI-71130 Kuopio, Finland
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Joseph NM, He S, Quintana E, Kim YG, Núñez G, Morrison SJ. Enteric glia are multipotent in culture but primarily form glia in the adult rodent gut. J Clin Invest 2011; 121:3398-411. [PMID: 21865643 DOI: 10.1172/jci58186] [Citation(s) in RCA: 177] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Accepted: 06/27/2011] [Indexed: 01/02/2023] Open
Abstract
It is unclear whether neurogenesis occurs in the adult mammalian enteric nervous system (ENS). Neural crest-derived cells capable of forming multilineage colonies in culture, and neurons and glia upon transplantation into chick embryos, persist throughout adult life in the mammalian ENS. In this study we sought to determine the physiological function of these cells. We discovered that these cells could be identified based on CD49b expression and that they had characteristics of enteric glia, including p75, GFAP, S100B, and SOX10 expression. To test whether new neurons or glia arise in the adult gut under physiological conditions, we marked dividing progenitors with a thymidine analog in rodents under steady-state conditions, or during aging, pregnancy, dietary changes, hyperglycemia, or exercise. We also tested gut injuries including inflammation, irradiation, benzalkonium chloride treatment, partial gut stenosis, and glial ablation. We readily observed neurogenesis in a neurogenic region of the central nervous system, but not reproducibly in the adult ENS. Lineage tracing of glial cells with GFAP-Cre and GFAP-CreERT2 also detected little or no adult ENS neurogenesis. Neurogenesis in the adult gut is therefore very limited under the conditions we studied. In contrast, ENS gliogenesis was readily observed under steady-state conditions and after injury. Adult enteric glia thus have the potential to form neurons and glia in culture but are fated to form mainly glia under physiological conditions and after the injuries we studied.
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Affiliation(s)
- Nancy M Joseph
- Center for Stem Cell Biology, Howard Hughes Medical Institute, and Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
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243
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Neural stem cells: historical perspective and future prospects. Neuron 2011; 70:614-25. [PMID: 21609820 DOI: 10.1016/j.neuron.2011.05.005] [Citation(s) in RCA: 121] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/04/2011] [Indexed: 12/21/2022]
Abstract
How a single fertilized cell generates diverse neuronal populations has been a fundamental biological problem since the 19(th) century. Classical histological methods revealed that postmitotic neurons are produced in a precise temporal and spatial order from germinal cells lining the cerebral ventricles. In the 20(th) century, DNA labeling and histo- and immunohistochemistry helped to distinguish the subtypes of dividing cells and delineate their locations in the ventricular and subventricular zones. Recently, genetic and cell biological methods have provided insights into sequential gene expression and molecular and cellular interactions that generate heterogeneous populations of NSCs leading to specific neuronal classes. This precisely regulated developmental process does not tolerate significant in vivo deviation, making replacement of adult neurons by NSCs during pathology a colossal challenge. In contrast, utilizing the trophic factors emanating from the NSC or their derivatives to slow down deterioration or prevent death of degenerating neurons may be a more feasible strategy.
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244
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Li Y, Luo J, Lau WM, Zheng G, Fu S, Wang TT, Zeng HP, So KF, Chung SK, Tong Y, Liu K, Shen J. Caveolin-1 plays a crucial role in inhibiting neuronal differentiation of neural stem/progenitor cells via VEGF signaling-dependent pathway. PLoS One 2011; 6:e22901. [PMID: 21826216 PMCID: PMC3149620 DOI: 10.1371/journal.pone.0022901] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Accepted: 07/08/2011] [Indexed: 01/17/2023] Open
Abstract
In the present study, we aim to elucidate the roles of caveolin-1(Cav-1), a 22 kDa protein in plasma membrane invaginations, in modulating neuronal differentiation of neural progenitor cells (NPCs). In the hippocampal dentate gyrus, we found that Cav-1 knockout mice revealed remarkably higher levels of vascular endothelial growth factor (VEGF) and the more abundant formation of newborn neurons than wild type mice. We then studied the potential mechanisms of Cav-1 in modulating VEGF signaling and neuronal differentiation in isolated cultured NPCs under normoxic and hypoxic conditions. Hypoxic embryonic rat NPCs were exposed to 1% O2 for 24 h and then switched to 21% O2 for 1, 3, 7 and 14 days whereas normoxic NPCs were continuously cultured with 21% O2. Compared with normoxic NPCs, hypoxic NPCs had down-regulated expression of Cav-1 and up-regulated VEGF expression and p44/42MAPK phosphorylation, and enhanced neuronal differentiation. We further studied the roles of Cav-1 in inhibiting neuronal differentiation by using Cav-1 scaffolding domain peptide and Cav-1-specific small interfering RNA. In both normoxic and hypoxic NPCs, Cav-1 peptide markedly down-regulated the expressions of VEGF and flk1, decreased the phosphorylations of p44/42MAPK, Akt and Stat3, and inhibited neuronal differentiation, whereas the knockdown of Cav-1 promoted the expression of VEGF, phosphorylations of p44/42MAPK, Akt and Stat3, and stimulated neuronal differentiation. Moreover, the enhanced phosphorylations of p44/42MAPK, Akt and Stat3, and neuronal differentiation were abolished by co-treatment of VEGF inhibitor V1. These results provide strong evidence to prove that Cav-1 can inhibit neuronal differentiation via down-regulations of VEGF, p44/42MAPK, Akt and Stat3 signaling pathways, and that VEGF signaling is a crucial target of Cav-1. The hypoxia-induced down-regulation of Cav-1 contributes to enhanced neuronal differentiation in NPCs.
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Affiliation(s)
- Yue Li
- School of Chinese Medicine, The University of Hong Kong, Hong Kong SAR, China
- Research Centre of Heart, Brain, Hormone and Healthy Aging, The University of Hong Kong, Hong Kong SAR, China
| | - Jianmin Luo
- School of Chinese Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Wui-Man Lau
- Research Centre of Heart, Brain, Hormone and Healthy Aging, The University of Hong Kong, Hong Kong SAR, China
- State Key Laboratory of Brain and Cognitive Sciences, Department of Anatomy, The University of Hong Kong, Hong Kong SAR, China
| | - Guoqing Zheng
- School of Chinese Medicine, The University of Hong Kong, Hong Kong SAR, China
- Center of Neurology and Rehabilitation, The Second Affiliated Hospital of Wenzhou Medical College, Wenzhou, China
| | - Shuping Fu
- School of Chinese Medicine, The University of Hong Kong, Hong Kong SAR, China
- Research Centre of Heart, Brain, Hormone and Healthy Aging, The University of Hong Kong, Hong Kong SAR, China
| | - Ting-Ting Wang
- Research Centre of Heart, Brain, Hormone and Healthy Aging, The University of Hong Kong, Hong Kong SAR, China
- Institute of Functional Molecule, School of Chemistry, South China University of Technology, Guangzhou, China
| | - He-Ping Zeng
- Institute of Functional Molecule, School of Chemistry, South China University of Technology, Guangzhou, China
| | - Kwok-Fai So
- Research Centre of Heart, Brain, Hormone and Healthy Aging, The University of Hong Kong, Hong Kong SAR, China
- State Key Laboratory of Brain and Cognitive Sciences, Department of Anatomy, The University of Hong Kong, Hong Kong SAR, China
| | - Sookja Kim Chung
- Research Centre of Heart, Brain, Hormone and Healthy Aging, The University of Hong Kong, Hong Kong SAR, China
- State Key Laboratory of Brain and Cognitive Sciences, Department of Anatomy, The University of Hong Kong, Hong Kong SAR, China
| | - Yao Tong
- School of Chinese Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Kejian Liu
- Center of Biomedical Research Excellence, College of Pharmacy, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - Jiangang Shen
- School of Chinese Medicine, The University of Hong Kong, Hong Kong SAR, China
- Research Centre of Heart, Brain, Hormone and Healthy Aging, The University of Hong Kong, Hong Kong SAR, China
- * E-mail:
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Therapeutic hypothermia influences cell genesis and survival in the rat hippocampus following global ischemia. J Cereb Blood Flow Metab 2011; 31:1725-35. [PMID: 21364603 PMCID: PMC3170941 DOI: 10.1038/jcbfm.2011.25] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Delayed hypothermia salvages CA1 neurons from global ischemic injury. However, the effects of this potent neuroprotectant on endogenous repair mechanisms, such as neurogenesis, have not been clearly examined. In this study, we quantified and phenotyped newly generated cells within the hippocampus following untreated and hypothermia-treated ischemia. We first show that CA1 pyramidal neurons did not spontaneously regenerate after ischemia. We then compared the level of neuroprotection when hypothermia was initiated either during or after ischemia. Treatment efficacy decreased with longer delays, but hypothermia delayed for up to 12 hours was neuroprotective. Although bromodeoxyuridine (BrdU) incorporation was elevated in ischemic groups, CA1 neurogenesis did not occur as the BrdU label did not colocalize with neuronal nuclei (NeuN) in any of the groups. Instead, the majority of BrdU-labeled cells were Iba-positive microglia, and neuroprotective hypothermia decreased the delayed generation of microglia during the third postischemic week. Conversely, hypothermia delayed for 12 hours significantly increased the survival of newly generated dentate granule cells at 4 weeks after ischemia. Thus, our findings show that CA1 neurogenesis does not contribute to hypothermic neuroprotection. Importantly, we also show that prolonged hypothermia positively interacts with postischemic repair processes, such as neurogenesis, resulting in improved functional outcome.
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246
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Wójcik-Stanaszek L, Sypecka J, Szymczak P, Ziemka-Nalecz M, Khrestchatisky M, Rivera S, Zalewska T. The potential role of metalloproteinases in neurogenesis in the gerbil hippocampus following global forebrain ischemia. PLoS One 2011; 6:e22465. [PMID: 21799862 PMCID: PMC3143139 DOI: 10.1371/journal.pone.0022465] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Accepted: 06/28/2011] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Matrix metalloproteinases (MMPs) have recently been considered to be involved in the neurogenic response of adult neural stem/progenitor cells. However, there is a lack of information showing direct association between the activation of MMPs and the development of neuronal progenitor cells involving proliferation and/or further differentiation in vulnerable (Cornus Ammoni-CA1) and resistant (dentate gyrus-DG) to ischemic injury areas of the brain hippocampus. PRINCIPAL FINDINGS We showed that dynamics of MMPs activation in the dentate gyrus correlated closely with the rate of proliferation and differentiation of progenitor cells into mature neurons. In contrast, in the damaged CA1 pyramidal cells layer, despite the fact that some proliferating cells exhibited antigen specific characteristic of newborn neuronal cells, these did not attain maturity. This coincides with the low, near control-level, activity of MMPs. The above results are supported by our in vitro study showing that MMP inhibitors interfered with both the proliferation and differentiation of the human neural stem cell line derived from umbilical cord blood (HUCB-NSCs) toward the neuronal lineage. CONCLUSION Taken together, the spatial and temporal profiles of MMPs activity suggest that these proteinases could be an important component in neurogenesis-associated processes in post-ischemic brain hippocampus.
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Affiliation(s)
- Luiza Wójcik-Stanaszek
- NeuroRepair Department, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Joanna Sypecka
- NeuroRepair Department, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Patrycja Szymczak
- NeuroRepair Department, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Malgorzata Ziemka-Nalecz
- NeuroRepair Department, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Michel Khrestchatisky
- Neurobiologie des Interactions Cellulaires et Neurophysiopathologie (NICN), UMR 6184, CNRS, Aix-Marseille University, Marseille, France
| | - Santiago Rivera
- Neurobiologie des Interactions Cellulaires et Neurophysiopathologie (NICN), UMR 6184, CNRS, Aix-Marseille University, Marseille, France
| | - Teresa Zalewska
- NeuroRepair Department, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
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Park SW, Yi JW, Kim YM, Kang JM, Kim DO, Shin MS, Kim CJ, Lee DI, Kim DH, Lee BJ. Remifentanil alleviates transient cerebral ischemia-induced memory impairment through suppression of apoptotic neuronal cell death in gerbils. Korean J Anesthesiol 2011; 61:63-8. [PMID: 21860753 PMCID: PMC3155139 DOI: 10.4097/kjae.2011.61.1.63] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Revised: 01/10/2011] [Accepted: 01/20/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND During neurosurgical procedures, patients are often exposed to hypoxic and ischemic brain damage. Cerebral ischemia leads to neuronal cell death and eventually causes neurological impairments. Remifentanil is a new ultra-short acting phenylpiperidine opioid analgesic. In this study, we evaluated remifentanil to determine if it exerts an anti-apoptotic effect in the hippocampal dentate gyrus following transient global ischemia in gerbils. METHODS Step-down avoidance task, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay, and immunohistochemical staining for caspase-3 were performed. RESULTS The numbers of TUNEL-positive cells and caspase-3-positive cells in the dentate gyrus were increased by ransient global ischemia. Latency in the step-down avoidance task was increased by transient global ischemia. Results revealed that apoptotic cell death in the dentate gyrus was increased significantly following transient global ischemia, resulting in memory impairment. However, treatment with remifentanil suppressed ischemia-induced apoptosis in the dentate gyrus, thereby alleviating the memory impairment that was induced by ischemic cerebral injury. CONCLUSIONS These results indicate that remifentanil may exert a neuroprotective effect on ischemic brain damage during surgery.
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Affiliation(s)
- Sung-Wook Park
- Department of Anesthesiology and Pain Medicine, College of Medicine, Kyung Hee University, Seoul, Korea
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Patil AA, Andrews RV. Nonresective hippocampal surgery for epilepsy. World Neurosurg 2011; 74:645-9. [PMID: 21492634 DOI: 10.1016/j.wneu.2010.06.032] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Accepted: 06/15/2010] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Clinical experience with a new surgical procedure called multiple hippocampal transections is described. In this procedure, seizure circuits within the hippocampus are disrupted by making multiple cuts parallel to the hippocampal digitations; while the vertical functional fibers are preserved. METHODS Ten patients with temporal lobe epilepsy are described. The male/female ratio is 6:4, the ages of the patients were 20-53 years, and follow-up periods were 10-34 months, with a median of 21 months. Five patients had no hippocampal sclerosis, two had minimal sclerosis, and three had significant sclerosis. Six patients had surgery on the dominant side and five had failed the Wada test. Multiple hippocampal transections were made at 4-mm intervals. The neocortex was then treated with multiple subpial transections. In addition, six patients had resections of the temporal tip. RESULTS There were no permanent neurologic complications: seven patients are seizure-free, two have rare seizures, and one has 60% decrease in seizure frequency. Eight patients had both pre- and postoperative memory testing. Among these eight patients, five had improved verbal memory, three had improved visual memory, and three had a slight drop in visual memory. CONCLUSION This is a small series with a short follow-up period. However, the results are encouraging enough to warrant further trials. In addition, this may be an effective alternative procedure for those who fail the Wada test and do not have significant temporal lobe sclerosis or who have seizures originating from the dominant side.
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Immunohistological markers for proliferative events, gliogenesis, and neurogenesis within the adult hippocampus. Cell Tissue Res 2011; 345:1-19. [PMID: 21647561 DOI: 10.1007/s00441-011-1196-4] [Citation(s) in RCA: 237] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Accepted: 05/13/2011] [Indexed: 12/29/2022]
Abstract
Biologists long believed that, once development is completed, no new neurons are produced in the forebrain. However, as is now firmly established, new neurons can be produced at least in two specific forebrain areas: the subventricular zone (SVZ) and the dentate gyrus (DG) of the hippocampal formation. Neurogenesis within the adult DG occurs constitutively throughout postnatal life, and the rate of neurogenesis within the DG can be altered under various physiological and pathophysiological conditions. The process of adult neurogenesis within the DG is a multi-step process (proliferation, differentiation, migration, targeting, and synaptic integration) that ends with the formation of a post-mitotic functionally integrated new neuron. Various markers are expressed during specific stages of adult neurogenesis. The availability of such markers allows the time-course and fate of newly born cells to be followed within the DG in a detailed and precise fashion. Several of the available markers (e.g., PCNA, Ki-67, PH3, MCM2) are markers for proliferative events, whereas others are more specific for early phases of neurogenesis and gliogenesis within the adult DG (e.g., nestin, GFAP, Sox2, Pax6). In addition, markers are available allowing events to be distinguished that are related to later steps of gliogenesis (e.g., vimentin, BLBP, S100beta) or neurogenesis (e.g., NeuroD, PSA-NCAM, DCX).
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Abstract
Neuronal nitric oxide synthase (nNOS) is mainly expressed in neurons, to some extent in astrocytes and neuronal stem cells. The alternative splicing of nNOS mRNA generates 5 isoforms of nNOS, including nNOS-α, nNOS-β, nNOS-µ, nNOS-γ and nNOS-2. Monomer of nNOS is inactive, and dimer is the active form. Dimerization requires tetrahydrobiopterin (BH4), heme and L-arginine binding. Regulation of nNOS expression relies largely on cAMP response element-binding protein (CREB) activity, and nNOS activity is regulated by heat shock protein 90 (HSP90)/HSP70, calmodulin (CaM), phosphorylation and dephosphorylation at Ser847 and Ser1412, and the protein inhibitor of nNOS (PIN). There are primarily 9 nNOS-interacting proteins, including post-synaptic density protein 95 (PSD95), clathrin assembly lymphoid leukemia (CALM), calcium/calmodulin-dependent protein kinase II alpha (CAMKIIA), Disks large homolog 4 (DLG4), DLG2, 6-phosphofructokinase, muscle type (PFK-M), carboxy-terminal PDZ ligand of nNOS (CAPON) protein, syntrophin and dynein light chain (LC). Among them, PSD95, CAPON and PFK-M are important nNOS adapter proteins in neurons. The interaction of PSD95 with nNOS controls synapse formation and is implicated in N-methyl-D-aspartic acid-induced neuronal death. nNOS-derived NO is implicated in synapse loss-mediated early cognitive/motor deficits in several neuropathological states, and negatively regulates neurogenesis under physiological and pathological conditions.
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