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Ma Y, Qiao Y, Gao X. Potential role of hippocampal neurogenesis in spinal cord injury induced post-trauma depression. Neural Regen Res 2024; 19:2144-2156. [PMID: 38488549 PMCID: PMC11034606 DOI: 10.4103/1673-5374.392855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 11/02/2023] [Accepted: 11/29/2023] [Indexed: 04/24/2024] Open
Abstract
It has been reported both in clinic and rodent models that beyond spinal cord injury directly induced symptoms, such as paralysis, neuropathic pain, bladder/bowel dysfunction, and loss of sexual function, there are a variety of secondary complications, including memory loss, cognitive decline, depression, and Alzheimer's disease. The large-scale longitudinal population-based studies indicate that post-trauma depression is highly prevalent in spinal cord injury patients. Yet, few basic studies have been conducted to address the potential molecular mechanisms. One of possible factors underlying the depression is the reduction of adult hippocampal neurogenesis which may come from less physical activity, social isolation, chronic pain, and elevated neuroinflammation after spinal cord injury. However, there is no clear consensus yet. In this review, we will first summarize the alteration of hippocampal neurogenesis post-spinal cord injury. Then, we will discuss possible mechanisms underlie this important spinal cord injury consequence. Finally, we will outline the potential therapeutic options aimed at enhancing hippocampal neurogenesis to ameliorate depression.
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Affiliation(s)
- Ying Ma
- Spinal Cord and Brain Injury Research Group, Stark Neuroscience Research Institute, Indianapolis, IN, USA
- Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
- Department of Neurology, Shengjing Hospital of China Medical University, Shenyang, Liaoning Province, China
| | - Yue Qiao
- Department of Neurology, Shengjing Hospital of China Medical University, Shenyang, Liaoning Province, China
| | - Xiang Gao
- Spinal Cord and Brain Injury Research Group, Stark Neuroscience Research Institute, Indianapolis, IN, USA
- Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
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2
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Malik SC, Lin JD, Ziegler-Waldkirch S, Tholen S, Deshpande SS, Schwabenland M, Schilling O, Vlachos A, Meyer-Luehmann M, Schachtrup C. Tpr Misregulation in Hippocampal Neural Stem Cells in Mouse Models of Alzheimer's Disease. Cells 2023; 12:2757. [PMID: 38067185 PMCID: PMC10706632 DOI: 10.3390/cells12232757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 11/19/2023] [Accepted: 11/29/2023] [Indexed: 12/18/2023] Open
Abstract
Nuclear pore complexes (NPCs) are highly dynamic macromolecular protein structures that facilitate molecular exchange across the nuclear envelope. Aberrant NPC functioning has been implicated in neurodegeneration. The translocated promoter region (Tpr) is a critical scaffolding nucleoporin (Nup) of the nuclear basket, facing the interior of the NPC. However, the role of Tpr in adult neural stem/precursor cells (NSPCs) in Alzheimer's disease (AD) is unknown. Using super-resolution (SR) and electron microscopy, we defined the different subcellular localizations of Tpr and phospho-Tpr (P-Tpr) in NSPCs in vitro and in vivo. Elevated Tpr expression and reduced P-Tpr nuclear localization accompany NSPC differentiation along the neurogenic lineage. In 5xFAD mice, an animal model of AD, increased Tpr expression in DCX+ hippocampal neuroblasts precedes increased neurogenesis at an early stage, before the onset of amyloid-β plaque formation. Whereas nuclear basket Tpr interacts with chromatin modifiers and NSPC-related transcription factors, P-Tpr interacts and co-localizes with cyclin-dependent kinase 1 (Cdk1) at the nuclear chromatin of NSPCs. In hippocampal NSPCs in a mouse model of AD, aberrant Tpr expression was correlated with altered NPC morphology and counts, and Tpr was aberrantly expressed in postmortem human brain samples from patients with AD. Thus, we propose that altered levels and subcellular localization of Tpr in CNS disease affect Tpr functionality, which in turn regulates the architecture and number of NSPC NPCs, possibly leading to aberrant neurogenesis.
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Affiliation(s)
- Subash C. Malik
- Institute of Anatomy and Cell Biology, University of Freiburg, 79104 Freiburg, Germany; (S.C.M.); (J.-D.L.); (S.S.D.)
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Jia-Di Lin
- Institute of Anatomy and Cell Biology, University of Freiburg, 79104 Freiburg, Germany; (S.C.M.); (J.-D.L.); (S.S.D.)
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Stephanie Ziegler-Waldkirch
- Department of Neurology, Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany; (S.Z.-W.); (M.M.-L.)
| | - Stefan Tholen
- Institute of Surgical Pathology, Medical Center, University of Freiburg, 79106 Freiburg, Germany; (S.T.); (O.S.)
| | - Sachin S. Deshpande
- Institute of Anatomy and Cell Biology, University of Freiburg, 79104 Freiburg, Germany; (S.C.M.); (J.-D.L.); (S.S.D.)
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Marius Schwabenland
- Institute of Neuropathology, University of Freiburg, 79106 Freiburg, Germany
| | - Oliver Schilling
- Institute of Surgical Pathology, Medical Center, University of Freiburg, 79106 Freiburg, Germany; (S.T.); (O.S.)
| | - Andreas Vlachos
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany;
- Center BrainLinks-BrainTools, University of Freiburg, 79110 Freiburg, Germany
- Center for Basics in Neuromodulation (NeuroModul Basics), Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Melanie Meyer-Luehmann
- Department of Neurology, Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany; (S.Z.-W.); (M.M.-L.)
- Center for Basics in Neuromodulation (NeuroModul Basics), Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Christian Schachtrup
- Institute of Anatomy and Cell Biology, University of Freiburg, 79104 Freiburg, Germany; (S.C.M.); (J.-D.L.); (S.S.D.)
- Center for Basics in Neuromodulation (NeuroModul Basics), Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
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Harper J, Wilson S, Bair JL, Hunt RH, Thomas KM, Malone SM, Iacono WG. Testing the consequences of alcohol, cannabis, and nicotine use on hippocampal volume: a quasi-experimental cotwin control analysis of young adult twins. Psychol Med 2023; 53:2671-2681. [PMID: 37310301 PMCID: PMC10123841 DOI: 10.1017/s0033291721004682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 10/22/2021] [Accepted: 10/26/2021] [Indexed: 11/06/2022]
Abstract
BACKGROUND Alcohol, cannabis, and nicotine use are highly comorbid and alarmingly prevalent in young adults. The hippocampus may be particularly sensitive to substance exposure. This remains largely untested in humans and familial risk may confound exposure effects. We extend prior work on alcohol and hippocampal volume in women by testing common and unique substance use effects and the potential moderating role of sex on hippocampal volume during emerging adulthood. A quasi-experimental cotwin control (CTC) design was used to separate familial risk from exposure consequences. METHODS In a population-based sample of 435 24-year-old same-sex twins (58% women), dimensional measures (e.g. frequency, amount) of alcohol, cannabis, and nicotine use across emerging adulthood were assessed. Hippocampal volume was assessed using MRI. RESULTS Greater substance use was significantly associated with lower hippocampal volume for women but not men. The same pattern was observed for alcohol, cannabis, and nicotine. CTC analyses provided evidence that hippocampal effects likely reflected familial risk and the consequence of substance use in general and alcohol and nicotine in particular; cannabis effects were in the expected direction but not significant. Within-pair mediation analyses suggested that the effect of alcohol use on the hippocampus may reflect, in part, comorbid nicotine use. CONCLUSIONS The observed hippocampal volume deviations in women likely reflected substance-related premorbid familial risk and the consequences of smoking and, to a lesser degree, drinking. Findings contribute to a growing body of work suggesting heightened risk among women toward experiencing deleterious effects of substance exposure on the still-developing young adult hippocampus.
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Affiliation(s)
- Jeremy Harper
- Department of Psychiatry & Behavioral Sciences, University of Minnesota, Twin Cities, USA
| | - Sylia Wilson
- Institute of Child Development, University of Minnesota, Twin Cities, USA
| | - Jessica L. Bair
- Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, USA
| | - Ruskin H. Hunt
- Institute of Child Development, University of Minnesota, Twin Cities, USA
| | - Kathleen M. Thomas
- Institute of Child Development, University of Minnesota, Twin Cities, USA
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Qiao X, Lu L, Zhou K, Tan L, Liu X, Ni J, Hou Y, Liang J, Dou H. The correlation between proteoglycan 2 and neuropsychiatric systemic lupus erythematosus. Clin Immunol 2022; 239:109042. [PMID: 35568106 DOI: 10.1016/j.clim.2022.109042] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 05/09/2022] [Accepted: 05/09/2022] [Indexed: 02/06/2023]
Abstract
The proposed pathogenesis of neuropsychiatric systemic lupus erythematosus (NPSLE) mainly includes ischemia and neuroinflammation mechanisms. Protein encoded by Proteoglycan 2 (PRG2) mRNA is involved in the immune process related to eosinophils, also being found in the placenta and peripheral blood of pregnant women. We evaluated the correlation between PRG2 and NPSLE for the first time and found that PRG2 protein is overexpressed in the serum of patients with NPSLE and correlated with the SLE disease activity index (SLEDAI) subset scores of psychosis. Moreover, we investigated the correlation between hippocampal PRG2 level and hippocampally dependent learning and memory ability in MRL/lpr mice, and discovered that the number of PRG2+GFAP+ astrocytes in the cortex and hypothalamus and the number of PRG2+IBA-1+ microglia in the hippocampus and cortex significantly increased in the MRL/lpr mice. These data provided a reference for the follow-up exploration of the role of PRG2 in SLE or other diseases.
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Affiliation(s)
- Xiaoyue Qiao
- The State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing 210093, China
| | - Li Lu
- The State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing 210093, China
| | - Kangxing Zhou
- Department of Rheumatology and Immunology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing 210008, China
| | - Liping Tan
- The State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing 210093, China
| | - Xuan Liu
- The State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing 210093, China
| | - Jiali Ni
- The State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing 210093, China
| | - Yayi Hou
- The State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing 210093, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing 210093, China.
| | - Jun Liang
- Department of Rheumatology and Immunology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing 210008, China.
| | - Huan Dou
- The State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing 210093, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing 210093, China.
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5
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Role of Excitatory Amino Acid Carrier 1 ( EAAC1) in Neuronal Death and Neurogenesis After Ischemic Stroke. Int J Mol Sci 2020; 21:ijms21165676. [PMID: 32784778 PMCID: PMC7460875 DOI: 10.3390/ijms21165676] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 08/03/2020] [Accepted: 08/05/2020] [Indexed: 12/24/2022] Open
Abstract
Although there have been substantial advances in knowledge regarding the mechanisms of neuron death after stroke, effective therapeutic measures for stroke are still insufficient. Excitatory amino acid carrier 1 (EAAC1) is a type of neuronal glutamate transporter and considered to have an additional action involving the neuronal uptake of cysteine, which acts as a crucial substrate for glutathione synthesis. Previously, our lab demonstrated that genetic deletion of EAAC1 leads to decreased neuronal glutathione synthesis, increased oxidative stress, and subsequent cognitive impairment. Therefore, we hypothesized that reduced neuronal transport of cysteine due to deletion of the EAAC1 gene might exacerbate neuronal injury and impair adult neurogenesis in the hippocampus after transient cerebral ischemia. EAAC1 gene deletion profoundly increased ischemia-induced neuronal death by decreasing the antioxidant capacity. In addition, genetic deletion of EAAC1 also decreased the overall neurogenesis processes, such as cell proliferation, differentiation, and survival, after cerebral ischemia. These studies strongly support our hypothesis that EAAC1 is crucial for the survival of newly generated neurons, as well as mature neurons, in both physiological and pathological conditions. Here, we present a comprehensive review of the role of EAAC1 in neuronal death and neurogenesis induced by ischemic stroke, focusing on its potential cellular and molecular mechanisms.
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6
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Cognitive impairments in adult mice with RIP140 overexpression in neural stem cells. Behav Brain Res 2020; 393:112777. [PMID: 32579978 DOI: 10.1016/j.bbr.2020.112777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 05/27/2020] [Accepted: 06/16/2020] [Indexed: 12/31/2022]
Abstract
Receptor-interacting protein 140 (RIP140) is a transcription co-regulator of several transcription factors and a signal transduction regulator. RIP140 was recently implicated in the regulation of cognitive functions. The gene that encodes RIP140 is located on chromosome 21. An increase in RIP140 expression was observed in the fetal cerebral cortex and hippocampus in Down syndrome patients who exhibited strong cognitive disabilities. We hypothesized that RIP140 overexpression affects cognitive function in adult neural development. The present study used a Cre-dependent adeno-associated virus to selectively overexpress RIP140 in neural stem cells using nestin-Cre mice. RIP140 overexpression efficiency was evaluated at the subgranular zone (SGZ) of the dorsal dentate gyrus (dDG) and the subventricular zone (SVZ) of the lateral ventricles (LVs). Mice with RIP140 overexpression in the SGZ exhibited deficits in cognitive function and spatial learning and memory, measured in the Morris water maze, object-place recognition test, and novel object recognition test. However, overexpression of RIP140 in SVZ only impaired performance in the Morris water maze and novel object recognition test but not in the object-place recognition test. Altogether, these results indicated defects in cognitive functions that were associated with RIP140 overexpression in neural stem cells and revealed a behavioral phenotype that may be used as a framework for further investigating the neuropathogenesis of Down syndrome.
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7
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Murray KD, Liu XB, King AN, Luu JD, Cheng HJ. Age-Related Changes in Synaptic Plasticity Associated with Mossy Fiber Terminal Integration during Adult Neurogenesis. eNeuro 2020; 7:ENEURO.0030-20.2020. [PMID: 32332082 PMCID: PMC7240290 DOI: 10.1523/eneuro.0030-20.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 03/27/2020] [Accepted: 04/12/2020] [Indexed: 12/17/2022] Open
Abstract
Mouse hippocampus retains the capacity for neurogenesis throughout lifetime, but such plasticity decreases with age. Adult hippocampal neurogenesis (AHN) involves the birth, maturation, and synaptic integration of newborn granule cells (GCs) into preexisting hippocampal circuitry. While functional integration onto adult-born GCs has been extensively studied, maturation of efferent projections onto CA3 pyramidal cells is less understood, particularly in aged brain. Here, using combined light and reconstructive electron microscopy (EM), we describe the maturation of mossy fiber bouton (MFB) connectivity with CA3 pyramidal cells in young adult and aged mouse brain. We found mature synaptic contacts of newborn GCs were formed in both young and aged brains. However, the dynamics of their spatiotemporal development and the cellular process by which these cells functionally integrated over time were different. In young brain newborn GCs either formed independent nascent MFB synaptic contacts or replaced preexisting MFBs, but these contacts were pruned over time to a mature state. In aged brain only replacement of preexisting MFBs was observed and new contacts were without evidence of pruning. These data illustrate that functional synaptic integration of AHN occurs in young adult and aged brain, but with distinct dynamics. They suggest elimination of preexisting connectivity is required for the integration of adult-born GCs in aged brain.
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Affiliation(s)
- Karl D Murray
- Center for Neuroscience
- Department of Psychiatry and Behavioral Neuroscience
| | | | | | | | - Hwai-Jong Cheng
- Center for Neuroscience
- Department of Neurobiology, Physiology and behavior
- Department of Pathology and Laboratory Medicine, University of California, Davis, Davis, CA 95618
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8
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Keshavarzi M, Khoshnoud MJ, Ghaffarian Bahraman A, Mohammadi-Bardbori A. An Endogenous Ligand of Aryl Hydrocarbon Receptor 6-Formylindolo[3,2-b]Carbazole (FICZ) Is a Signaling Molecule in Neurogenesis of Adult Hippocampal Neurons. J Mol Neurosci 2020; 70:806-817. [DOI: 10.1007/s12031-020-01506-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 02/05/2020] [Indexed: 01/08/2023]
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9
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Zhao Z, Li B, Wu Y, Chen X, Guo Y, Shen Y, Huang H. Ketamine affects the integration of developmentally generated granule neurons in the adult stage. BMC Neurosci 2019; 20:60. [PMID: 31852437 PMCID: PMC6921590 DOI: 10.1186/s12868-019-0542-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 12/07/2019] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Ketamine has been reported to cause neonatal neurotoxicity in a variety of developing animal models. Various studies have been conducted to study the mechanism of neurotoxicity for general anesthetic use during the neonatal period. Previous experiments have suggested that developmentally generated granule neurons in the hippocampus dentate gyrus (DG) supported hippocampus-dependent memory. Therefore, this study aimed to investigate whether ketamine affects the functional integration of developmentally generated granule neurons in the DG. For this purpose,the postnatal day 7 (PND-7) Sprague-Dawley (SD) rats were divided into the control group and the ketamine group (rats who received 4 injections of 40 mg/kg ketamine at 1 h intervals). To label dividing cells, BrdU was administered for three consecutive days after the ketamine exposure; NeuN+/BrdU+cells were observed by using immunofluorescence. To evaluate the developmentally generated granule neurons that support hippocampus-dependent memory, spatial reference memory was tested by using Morris Water Maze at 3 months old, after which the immunofluorescence was used to detect c-Fos expression in the NeuN+/BrdU+ cells. The expression of caspase-3 was measured by western blot to detect the apoptosis in the hippocampal DG. RESULTS The present results showed that the neonatal ketamine exposure did not influence the survival rate of developmentally generated granule neurons at 2 and 3 months old, but ketamine interfered with the integration of these neurons into the hippocampal DG neural circuits and caused a deficit in hippocampal-dependent spatial reference memory tasks. CONCLUSIONS In summary, these findings may promote more studies to investigate the neurotoxicity of ketamine in the developing brain.
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Affiliation(s)
- Zhanqiang Zhao
- Department of Anesthesiology, Jiangning Hospital of Traditional Chinese Medicine, Nanjing, China
| | - Bing Li
- Department of Anesthesiology, Jiangning Hospital of Traditional Chinese Medicine, Nanjing, China
| | - Yuqing Wu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou, China
| | - Xujun Chen
- Department of Anesthesiology, Jiangning Hospital of Traditional Chinese Medicine, Nanjing, China
| | - Yan Guo
- Department of Anesthesiology, Jiangning Hospital of Traditional Chinese Medicine, Nanjing, China
| | - Yang Shen
- Department of Anesthesiology, Jiangning Hospital of Traditional Chinese Medicine, Nanjing, China
| | - He Huang
- Department of Anesthesiology, First Affiliated Hospital With Nanjing Medical University, Guangzhou Road 300, Nanjing, 210029, Jiangsu, People's Republic of China.
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10
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Algaidi SA, Eldomiaty MA, Elbastwisy YM, Almasry SM, Desouky MK, Elnaggar AM. Effect of voluntary running on expression of myokines in brains of rats with depression. Int J Immunopathol Pharmacol 2019; 33:2058738419833533. [PMID: 30834799 PMCID: PMC6407323 DOI: 10.1177/2058738419833533] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
This study aimed to demonstrate the histopathology and immunoexpression of exercise-derived myokines in dentate gyrus (DG), medial prefrontal cortex (mPFC) and cerebellum of depressed Wistar rats during depression and after practising voluntary running. Depression was developed by forced swimming for 2 weeks. Voluntary running was performed by voluntary running for 3 weeks. Brain sections were processed and immunostained to detect brain-derived neurotrophic factor (BDNF), macrophage migration inhibitory factor (MIF), vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6). ImageJ software was used to measure the optical density (OD). BDNF was expressed in neurons in DG, mPFC and granular and Purkinje cells in cerebellum. MIF was expressed in neurons of sub-granular zone in DG, mPFC and Purkinje cells. VEGF was expressed in many neurons in DG, mPFC and Purkinje cells. IL-6 was expressed in some neurons in DG, in neuropil of mPFC and in Purkinje cells. In depression, the OD of studied myokines significantly decreased in all examined areas. After voluntary running, the OD of myokines significantly increased in all areas. This study defines the immunohistochemical expression of myokines in brain areas in depression and after voluntary running and reveals the involvement of the mPFC and cerebellum in the pathophysiology of depression.
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Affiliation(s)
- Sami A Algaidi
- 1 Department of Anatomy, Faculty of Medicine, Taibah University, Almadinah Almunawarah, Saudi Arabia
| | - Magda A Eldomiaty
- 1 Department of Anatomy, Faculty of Medicine, Taibah University, Almadinah Almunawarah, Saudi Arabia.,2 Department of Anatomy, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Yasser M Elbastwisy
- 1 Department of Anatomy, Faculty of Medicine, Taibah University, Almadinah Almunawarah, Saudi Arabia.,3 Department of Anatomy, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Shaima M Almasry
- 1 Department of Anatomy, Faculty of Medicine, Taibah University, Almadinah Almunawarah, Saudi Arabia.,3 Department of Anatomy, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Maha K Desouky
- 1 Department of Anatomy, Faculty of Medicine, Taibah University, Almadinah Almunawarah, Saudi Arabia.,4 Department of Anatomy, Faculty of Medicine, Minia University, Minia, Egypt
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11
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Pircs K, Petri R, Jakobsson J. Crosstalk between MicroRNAs and Autophagy in Adult Neurogenesis: Implications for Neurodegenerative Disorders. Brain Plast 2018; 3:195-203. [PMID: 30151343 PMCID: PMC6091039 DOI: 10.3233/bpl-180066] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Adult neurogenesis in the mammalian brain, including in humans, occurs throughout life in distinct brain regions. Alterations in adult neurogenesis is a common phenomenon in several different neurodegenerative disorders, which is likely to contribute to the pathophysiology of these disorders. This review summarizes novel concepts related to the interplay between autophagy and microRNAs in control of adult neurogenesis, with a specific focus on its relevance to neurodegenerative diseases.
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Affiliation(s)
- Karolina Pircs
- Department of Experimental Medical Science, Laboratory of Molecular Neurogenetics, Wallenberg Neuroscience Center and Lund Stem Cell Center, Lund University, Lund, Sweden
| | - Rebecca Petri
- Department of Experimental Medical Science, Laboratory of Molecular Neurogenetics, Wallenberg Neuroscience Center and Lund Stem Cell Center, Lund University, Lund, Sweden
| | - Johan Jakobsson
- Department of Experimental Medical Science, Laboratory of Molecular Neurogenetics, Wallenberg Neuroscience Center and Lund Stem Cell Center, Lund University, Lund, Sweden
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12
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Gao C, Wang Q, Chung SK, Shen J. Crosstalk of metabolic factors and neurogenic signaling in adult neurogenesis: Implication of metabolic regulation for mental and neurological diseases. Neurochem Int 2017; 106:24-36. [DOI: 10.1016/j.neuint.2017.02.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 01/10/2017] [Accepted: 02/03/2017] [Indexed: 12/31/2022]
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Selenomethionine promoted hippocampal neurogenesis via the PI3K-Akt-GSK3β-Wnt pathway in a mouse model of Alzheimer's disease. Biochem Biophys Res Commun 2017; 485:6-15. [DOI: 10.1016/j.bbrc.2017.01.069] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 01/15/2017] [Indexed: 11/23/2022]
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14
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Eldomiaty MA, Almasry SM, Desouky MK, Algaidi SA. Voluntary running improves depressive behaviours and the structure of the hippocampus in rats: A possible impact of myokines. Brain Res 2016; 1657:29-42. [PMID: 27919728 DOI: 10.1016/j.brainres.2016.12.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 11/30/2016] [Accepted: 12/01/2016] [Indexed: 12/23/2022]
Abstract
This study investigated the impact of voluntary exercise on depressive behaviours, serum and hippocampal levels of myokines, and histopathological features of hippocampal formation in rats. Depressed rats were allowed to voluntarily run on a wheel for 3weeks. Locomotor activity was assessed by a forced swimming test and the myokine levels in sera and hippocampal homogenates were measured using Enzyme-linked Immunosorbent Assay. Brain sections were analysed for hippocampal structure and neuronal counts. Voluntary running produced significant increase in the distance moved by rats and significant decrease in immobility duration. After voluntary running, there were significant increases in serum and hippocampal brain-derived neurotrophic factor (BDNF) and macrophage migration inhibitory factor (MIF), significant increase in hippocampal vascular endothelial growth factor (VEGF), and significant decrease in serum interleukin-6 (IL-6). Significant correlation was detected between the serum levels of BDNF and MIF (r=0.276) as well as IL-6 (r=-0.340). In addition, significant correlation was observed between hippocampal BDNF levels and MIF (r=0.500) and VEGF levels (r=0.279). After voluntary running, there was significant decrease in number degenerated neurons in hippocampal areas and significant increase in number of healthy neurons in the upper limb of the dentate gyrus, but not in its lower limb, compared to depression group. This study showed the relation of myokines to the development and/or relief of depression, as well as the correlation between serum and hippocampal myokine levels. Attention should be paid to studying the biological effects of myokines on different hippocampal areas that could respond differently to treatments.
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Affiliation(s)
- Magda A Eldomiaty
- Department of Anatomy, Faculty of Medicine, Taibah University, Saudi Arabia; Department of Anatomy, Faculty of Medicine, Tanta University, Egypt.
| | - Shaima M Almasry
- Department of Anatomy, Faculty of Medicine, Taibah University, Saudi Arabia; Department of Anatomy, Faculty of Medicine, Mansura University, Egypt
| | - Maha K Desouky
- Department of Anatomy, Faculty of Medicine, Taibah University, Saudi Arabia; Department of Anatomy, Faculty of Medicine, Menia University, Egypt
| | - Sami A Algaidi
- Department of Anatomy, Faculty of Medicine, Taibah University, Saudi Arabia
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Zhang X, Song Y, Bao T, Yu M, Xu M, Guo Y, Wang Y, Zhang C, Zhao B. Antidepressant-like effects of acupuncture involved the ERK signaling pathway in rats. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2016; 16:380. [PMID: 27680977 PMCID: PMC5041500 DOI: 10.1186/s12906-016-1356-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2016] [Accepted: 09/13/2016] [Indexed: 12/14/2022]
Abstract
Background The extracellular signal-regulated kinase (ERK) signaling pathway is considered to be associated with the pathogenesis and treatment of depression. Acupuncture has been demonstrated to ameliorate depression-related behavior and promote neurogenesis. In this study, we explored the role of the ERK signaling pathway in the antidepressant-like effects of acupuncture in rats exposed to chronic unpredictable mild stress (CUMS). Methods Eighty male Sprague–Dawley rats were randomly divided into eight groups: control group, model group, model + Acupuncture group (Acu group), model + fluoxetine group (FLX group), model + DMSO group (DMSO group), model + PD98059 group (PD group), model + Acupuncture + PD98059 group (Acu + PD group) and model + fluoxetine + PD98059 group (FLX + PD group). Except for the control group, all rats were subjected to 3 weeks of CUMS protocols to induce depression. Acupuncture was carried out for 10 min at acupoints of Baihui (GV-20) and Yintang (GV-29) each day during the experimental procedure. The ERK signaling pathway was inhibited using PD98059 through intracerebroventricular injection. The depression-like behaviors were evaluated using the sucrose intake and open-field tests. The protein levels of ERK1/2, phosphor (p)-ERK1/2, cAMP response element-binding protein (CREB), p-CREB and brain-derived neurotrophic factor (BDNF) in the hippocampus were examined using western blot. Results Acupuncture ameliorated the depression-like behaviors and dysfunction of the ERK signaling pathway in the hippocampus of CUMS rats. PD98059 pretreatment inhibited the improvements brought about by acupuncture on the ERK signaling pathway. Conclusions Taken together, our results indicated that acupuncture had a significant antidepressant-like effect on CUMS-induced depression model rats, and the ERK signaling pathway was implicated in this effect.
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Kandola A, Hendrikse J, Lucassen PJ, Yücel M. Aerobic Exercise as a Tool to Improve Hippocampal Plasticity and Function in Humans: Practical Implications for Mental Health Treatment. Front Hum Neurosci 2016; 10:373. [PMID: 27524962 PMCID: PMC4965462 DOI: 10.3389/fnhum.2016.00373] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 07/11/2016] [Indexed: 12/24/2022] Open
Abstract
Aerobic exercise (AE) has been widely praised for its potential benefits to cognition and overall brain and mental health. In particular, AE has a potent impact on promoting the function of the hippocampus and stimulating neuroplasticity. As the evidence-base rapidly builds, and given most of the supporting work can be readily translated from animal models to humans, the potential for AE to be applied as a therapeutic or adjunctive intervention for a range of human conditions appears ever more promising. Notably, many psychiatric and neurological disorders have been associated with hippocampal dysfunction, which may underlie the expression of certain symptoms common to these disorders, including (aspects of) cognitive dysfunction. Augmenting existing treatment approaches using AE based interventions may promote hippocampal function and alleviate cognitive deficits in various psychiatric disorders that currently remain untreated. Incorporating non-pharmacological interventions into clinical treatment may also have a number of other benefits to patient well being, such as limiting the risk of adverse side effects. This review incorporates both animal and human literature to comprehensively detail how AE is associated with cognitive enhancements and stimulates a cascade of neuroplastic mechanisms that support improvements in hippocampal functioning. Using the examples of schizophrenia and major depressive disorder, the utility and implementation of an AE intervention to the clinical domain will be proposed, aimed to reduce cognitive deficits in these, and related disorders.
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Affiliation(s)
- Aaron Kandola
- Brain and Mental Health Lab, School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, MelbourneVIC, Australia; Amsterdam Brain and Cognition, University of AmsterdamAmsterdam, Netherlands
| | - Joshua Hendrikse
- Brain and Mental Health Lab, School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Melbourne VIC, Australia
| | - Paul J Lucassen
- Centre for Neuroscience, Swammerdam Institute of Life Sciences, University of Amsterdam Amsterdam, Netherlands
| | - Murat Yücel
- Brain and Mental Health Lab, School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Melbourne VIC, Australia
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Huang H, Liu CM, Sun J, Hao T, Xu CM, Wang D, Wu YQ. Ketamine Affects the Neurogenesis of the Hippocampal Dentate Gyrus in 7-Day-Old Rats. Neurotox Res 2016; 30:185-98. [PMID: 26966008 DOI: 10.1007/s12640-016-9615-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 02/22/2016] [Accepted: 03/01/2016] [Indexed: 01/20/2023]
Abstract
Ketamine has been reported to cause neonatal neurotoxicity via a neuronal apoptosis mechanism; however, no in vivo research has reported whether ketamine could affect postnatal neurogenesis in the hippocampal dentate gyrus (DG). A growing number of experiments suggest that postnatal hippocampal neurogenesis is the foundation of maintaining normal hippocampus function into adulthood. Therefore, this study investigated the effect of ketamine on hippocampal neurogenesis. Male Sprague-Dawley rats were divided into two groups: the control group (equal volume of normal saline), and the ketamine-anesthesia group (40 mg/kg ketamine in four injections at 1 h intervals). The S-phase marker 5-bromodeoxyuridine (BrdU) was administered after ketamine exposure to postnatal day 7 (PND-7) rats, and the neurogenesis in the hippocampal DG was assessed using single- or double-immunofluorescence staining. The expression of GFAP in the hippocampal DG was measured by western blot analysis. Spatial reference memory was tested by Morris water maze at 2 months after PND-7 rats exposed to ketamine treatment. The present results showed that neonatal ketamine exposure significantly inhibited neural stem cell (NSC) proliferation, decreased astrocytic differentiation, and markedly enhanced neuronal differentiation. The disruptive effect of ketamine on the proliferation and differentiation of NSCs lasted at least 1 week and disappeared by 2 weeks after ketamine exposure. Moreover, the migration of newborn neurons in the granule cell layer and the growth of astrocytes in the hippocampal DG were inhibited by ketamine on PND-37 and PND-44. Finally, ketamine caused a deficit in hippocampal-dependent spatial reference memory tasks at 2 months old. Our results suggested that ketamine may interfere with hippocampal neurogenesis and long-term neurocognitive function in PND-7 rats. These findings may provide a new perspective to explain the adult neurocognitive dysfunction induced by neonatal ketamine exposure.
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Affiliation(s)
- He Huang
- Department of Anesthesiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Cun-Ming Liu
- Department of Anesthesiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Jie Sun
- Department of Anesthesiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Ting Hao
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, China
| | - Chun-Mei Xu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, China
| | - Dan Wang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, China
| | - Yu-Qing Wu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou, China.
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18
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Yao ZH, Kang X, Yang L, Niu Y, Lu Y, Nie L. PBA regulates neurogenesis and cognition dysfunction after repeated electroconvulsive shock in a rat model. Psychiatry Res 2015; 230:331-40. [PMID: 26381183 DOI: 10.1016/j.psychres.2015.09.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 09/01/2015] [Accepted: 09/07/2015] [Indexed: 12/23/2022]
Abstract
Electroconvulsive therapy (ECT) was widely used to treat the refractory depression. But ECT led to the cognitive deficits plaguing the depression patients. The underlying mechanisms of the cognitive deficits remain elusive. Repeated electroconvulsive shock (rECS) was used to simulate ECT and explore the mechanisms of ECT during the animal studies. Previous studies showed rECS could lead to neurogenesis and cognitive impairment. But it was well known that neurogenesis could improve the cognition. So these suggested that the mechanism of the cognitive deficit after rECS was very complex. In present study, we explored the probable mechanisms of the cognitive deficit after rECS from neurogenesis aspect. We found the cognitive deficit was reversible and neurogenesis could bring a long-term beneficial effect on cognition. Astrogliosis and NR1 down-regulation probably participated in the reversible cognitive deficits after rECS. Phenylbutyric acid (PBA), generally as an agent to investigate the roles of histone acetylation, could prevent the reversible cognitive dysfunction, but PBA could diminish the long-term effect of enhanced cognition by rECS. These suggested that ECT could possibly bring the long-term beneficial cognitive effect by regulating neurogenesis.
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Affiliation(s)
- Zhao-Hui Yao
- Department of Geriatrics, Renmin Hospital of Wuhan University, #238 Jiefang Road, Wuhan 430060, China; Department of Pathophysiology, Key Laboratory of Neurological Diseases of Education Committee of China, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Xiang Kang
- Department of Pathophysiology, Key Laboratory of Neurological Diseases of Education Committee of China, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Liu Yang
- Department of Pathophysiology, Key Laboratory of Neurological Diseases of Education Committee of China, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yi Niu
- Department of Pathophysiology, Key Laboratory of Neurological Diseases of Education Committee of China, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ye Lu
- Department of Pathophysiology, Key Laboratory of Neurological Diseases of Education Committee of China, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Li Nie
- Department of Geriatrics, Renmin Hospital of Wuhan University, #238 Jiefang Road, Wuhan 430060, China
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Peretto P, Bonfanti L. Adult neurogenesis 20 years later: physiological function vs. brain repair. Front Neurosci 2015; 9:71. [PMID: 25798084 PMCID: PMC4351634 DOI: 10.3389/fnins.2015.00071] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 02/18/2015] [Indexed: 12/18/2022] Open
Affiliation(s)
- Paolo Peretto
- Neuroscience Institute Cavalieri Ottolenghi Orbassano, Italy ; Life Sciences and Systems Biology, University of Turin Torino, Italy
| | - Luca Bonfanti
- Neuroscience Institute Cavalieri Ottolenghi Orbassano, Italy ; Department of Veterinary Sciences, University of Turin Torino, Italy
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20
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Lazic SE, Fuss J, Gass P. Quantifying the behavioural relevance of hippocampal neurogenesis. PLoS One 2014; 9:e113855. [PMID: 25426717 PMCID: PMC4245232 DOI: 10.1371/journal.pone.0113855] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Accepted: 10/31/2014] [Indexed: 12/26/2022] Open
Abstract
Few studies that examine the neurogenesis-behaviour relationship formally establish covariation between neurogenesis and behaviour or rule out competing explanations. The behavioural relevance of neurogenesis might therefore be overestimated if other mechanisms account for some, or even all, of the experimental effects. A systematic review of the literature was conducted and the data reanalysed using causal mediation analysis, which can estimate the behavioural contribution of new hippocampal neurons separately from other mechanisms that might be operating. Results from eleven eligible individual studies were then combined in a meta-analysis to increase precision (representing data from 215 animals) and showed that neurogenesis made a negligible contribution to behaviour (standarised effect = 0.15; 95% CI = -0.04 to 0.34; p = 0.128); other mechanisms accounted for the majority of experimental effects (standardised effect = 1.06; 95% CI = 0.74 to 1.38; p = 1.7×10-11).
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Affiliation(s)
- Stanley E. Lazic
- In Silico Lead Discovery, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Johannes Fuss
- Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, University of Heidelberg, Medical Faculty Mannheim, Mannheim, Germany
| | - Peter Gass
- Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, University of Heidelberg, Medical Faculty Mannheim, Mannheim, Germany
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Lindsey BW, Di Donato S, Kaslin J, Tropepe V. Sensory-specific modulation of adult neurogenesis in sensory structures is associated with the type of stem cell present in the neurogenic niche of the zebrafish brain. Eur J Neurosci 2014; 40:3591-607. [PMID: 25231569 DOI: 10.1111/ejn.12729] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 08/08/2014] [Accepted: 08/20/2014] [Indexed: 01/15/2023]
Abstract
Teleost fishes retain populations of adult stem/progenitor cells within multiple primary sensory processing structures of the mature brain. Though it has commonly been thought that their ability to give rise to adult-born neurons is mainly associated with continuous growth throughout life, whether a relationship exists between the processing function of these structures and the addition of new neurons remains unexplored. We investigated the ultrastructural organisation and modality-specific neurogenic plasticity of niches located in chemosensory (olfactory bulb, vagal lobe) and visual processing (periventricular grey zone, torus longitudinalis) structures of the adult zebrafish (Danio rerio) brain. Transmission electron microscopy showed that the cytoarchitecture of sensory niches includes many of the same cellular morphologies described in forebrain niches. We demonstrate that cells with a radial-glial phenotype are present in chemosensory niches, while the niche of the caudal tectum contains putative neuroepithelial-like cells instead. This was supported by immunohistochemical evidence showing an absence of glial markers, including glial fibrillary acidic protein, glutamine synthetase, and S100β in the tectum. By exposing animals to sensory assays we further illustrate that stem/progenitor cells and their neuronal progeny within sensory structures respond to modality-specific stimulation at distinct stages in the process of adult neurogenesis - chemosensory niches at the level of neuronal survival and visual niches in the size of the stem/progenitor population. Our data suggest that the adult brain has the capacity for sensory-specific modulation of adult neurogenesis and that this property may be associated with the type of stem cell present in the niche.
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Affiliation(s)
- Benjamin W Lindsey
- Australian Regenerative Medicine Institute, Monash University Clayton Campus, Clayton, Vic., Australia
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22
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Fuchs C, Trazzi S, Torricella R, Viggiano R, De Franceschi M, Amendola E, Gross C, Calzà L, Bartesaghi R, Ciani E. Loss of CDKL5 impairs survival and dendritic growth of newborn neurons by altering AKT/GSK-3β signaling. Neurobiol Dis 2014; 70:53-68. [PMID: 24952363 PMCID: PMC4146476 DOI: 10.1016/j.nbd.2014.06.006] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 05/22/2014] [Accepted: 06/09/2014] [Indexed: 12/24/2022] Open
Abstract
Mutations in the X-linked cyclin-dependent kinase-like 5 (CDKL5) gene have been identified in a neurodevelopmental disorder characterized by early-onset intractable seizures, severe developmental delay, intellectual disability, and Rett's syndrome-like features. Since the physiological functions of CDKL5 still need to be elucidated, in the current study we took advantage of a new Cdkl5 knockout (KO) mouse model in order to shed light on the role of this gene in brain development. We mainly focused on the hippocampal dentate gyrus, a region that largely develops postnatally and plays a key role in learning and memory. Looking at the process of neurogenesis, we found a higher proliferation rate of neural precursors in Cdkl5 KO mice in comparison with wild type mice. However, there was an increase in apoptotic cell death of postmitotic granule neuron precursors, with a reduction in total number of granule cells. Looking at dendritic development, we found that in Cdkl5 KO mice the newly-generated granule cells exhibited a severe dendritic hypotrophy. In parallel, these neurodevelopmental defects were associated with impairment of hippocampus-dependent memory. Looking at the mechanisms whereby CDKL5 exerts its functions, we identified a central role of the AKT/GSK-3β signaling pathway. Overall our findings highlight a critical role of CDKL5 in the fundamental processes of brain development, namely neuronal precursor proliferation, survival and maturation. This evidence lays the basis for a better understanding of the neurological phenotype in patients carrying mutations in the CDKL5 gene. Loss of Cdkl5 decreases survival of postmitotic granule cells. Loss of Cdkl5 results in dendritic hypotrophy of newborn granule cells. Loss of Cdkl5 impairs hippocampus-dependent behavior. Loss of Cdkl5 alters the AKT/GSK-3β pathway.
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Affiliation(s)
- Claudia Fuchs
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Stefania Trazzi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Roberta Torricella
- Health Sciences and Technologies-Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, Italy
| | - Rocchina Viggiano
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | | | - Elena Amendola
- Mouse Biology Unit, European Molecular Biology Laboratory (EMBL), Monterotondo, Italy
| | - Cornelius Gross
- Mouse Biology Unit, European Molecular Biology Laboratory (EMBL), Monterotondo, Italy
| | - Laura Calzà
- Health Sciences and Technologies-Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, Italy
| | - Renata Bartesaghi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy
| | - Elisabetta Ciani
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy.
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