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Su Y, Zeng L, Deng R, Ye B, Tang S, Xiong Z, Sun T, Ding Q, Su W, Jing X, Gao Q, Wang X, Qiu Z, Chen K, Quan D, Guo X. Endogenous Electric Field-Coupled PD@BP Biomimetic Periosteum Promotes Bone Regeneration through Sensory Nerve via Fanconi Anemia Signaling Pathway. Adv Healthc Mater 2023; 12:e2203027. [PMID: 36652677 DOI: 10.1002/adhm.202203027] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 01/15/2023] [Indexed: 01/20/2023]
Abstract
To treat bone defects, repairing the nerve-rich periosteum is critical for repairing the local electric field. In this study, an endogenous electric field is coupled with 2D black phosphorus electroactive periosteum to explore its role in promoting bone regeneration through nerves. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are used to characterize the electrically active biomimetic periosteum. Here, the in vitro effects exerted by the electrically active periosteum on the transformation of Schwann cells into the repair phenotype, axon initial segment (AIS) and dense core vesicle (DCV) of sensory neurons, and bone marrow mesenchymal stem cells are assessed using SEM, immunofluorescence, RNA-sequencing, and calcium ion probes. The electrically active periosteum stimulates Schwann cells into a neuroprotective phenotype via the Fanconi anemia pathway, enhances the AIS effect of sensory neurons, regulates DCV transport, and releases neurotransmitters, promoting the osteogenic transformation of bone marrow mesenchymal stem cells. Microcomputed tomography and other in vivo techniques are used to study the effects of the electrically active periosteum on bone regeneration. The results show that the electrically active periosteum promotes nerve-induced osteogenic repair, providing a potential clinical strategy for bone regeneration.
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Affiliation(s)
- Yanlin Su
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, China
| | - Lian Zeng
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, China
| | - Rongli Deng
- PCFM Lab, School of Chemistry and School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, Guangdong, 510000, China
| | - Bing Ye
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, China
| | - Shuo Tang
- Department of Orthopedics, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, 510127, China
| | - Zekang Xiong
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, China
| | - Tingfang Sun
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, China
| | - Qiuyue Ding
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, China
| | - Weijie Su
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, China
| | - Xirui Jing
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, China
| | - Qing Gao
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, China
| | - Xiumei Wang
- School of Materials Science and Engineering, Tsinghua University, Beijing, 100000, China
| | - Zhiye Qiu
- Allgens Medical Technology Co., Ltd., Beijing, 100000, China
| | - Kaifang Chen
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, China
| | - Daping Quan
- PCFM Lab, School of Chemistry and School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, Guangdong, 510000, China
| | - Xiaodong Guo
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, China
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Baculis BC, Kesavan H, Weiss AC, Kim EH, Tracy GC, Ouyang W, Tsai NP, Chung HJ. Homeostatic regulation of extracellular signal-regulated kinase 1/2 activity and axonal K v7.3 expression by prolonged blockade of hippocampal neuronal activity. Front Cell Neurosci 2022; 16:838419. [PMID: 35966206 PMCID: PMC9366003 DOI: 10.3389/fncel.2022.838419] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 07/04/2022] [Indexed: 11/17/2022] Open
Abstract
Homeostatic plasticity encompasses the mechanisms by which neurons stabilize their synaptic strength and excitability in response to prolonged and destabilizing changes in their network activity. Prolonged activity blockade leads to homeostatic scaling of action potential (AP) firing rate in hippocampal neurons in part by decreased activity of N-Methyl-D-Aspartate receptors and subsequent transcriptional down-regulation of potassium channel genes including KCNQ3 which encodes Kv7.3. Neuronal Kv7 channels are mostly heterotetramers of Kv7.2 and Kv7.3 subunits and are highly enriched at the axon initial segment (AIS) where their current potently inhibits repetitive and burst firing of APs. However, whether a decrease in Kv7.3 expression occurs at the AIS during homeostatic scaling of intrinsic excitability and what signaling pathway reduces KCNQ3 transcript upon prolonged activity blockade remain unknown. Here, we report that prolonged activity blockade in cultured hippocampal neurons reduces the activity of extracellular signal-regulated kinase 1/2 (ERK1/2) followed by a decrease in the activation of brain-derived neurotrophic factor (BDNF) receptor, Tropomyosin receptor kinase B (TrkB). Furthermore, both prolonged activity blockade and prolonged pharmacological inhibition of ERK1/2 decrease KCNQ3 and BDNF transcripts as well as the density of Kv7.3 and ankyrin-G at the AIS. Collectively, our findings suggest that a reduction in the ERK1/2 activity and subsequent transcriptional down-regulation may serve as a potential signaling pathway that links prolonged activity blockade to homeostatic control of BDNF-TrkB signaling and Kv7.3 density at the AIS during homeostatic scaling of AP firing rate.
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Affiliation(s)
- Brian C. Baculis
- Neuroscience Program, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
| | - Harish Kesavan
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
| | - Amanda C. Weiss
- Neuroscience Program, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
| | - Edward H. Kim
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
| | - Gregory C. Tracy
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
| | - Wenhao Ouyang
- Neuroscience Program, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
| | - Nien-Pei Tsai
- Neuroscience Program, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
| | - Hee Jung Chung
- Neuroscience Program, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
- Institute of Genomic Biology, University of Illinois at Urbana-Champaign, Champaign, IL, United States
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Wollet M, Kim JH. Brain-Derived Neurotrophic Factor Is Involved in Activity-Dependent Tonotopic Refinement of MNTB Neurons. Front Neural Circuits 2022; 16:784396. [PMID: 35185479 PMCID: PMC8850952 DOI: 10.3389/fncir.2022.784396] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 01/07/2022] [Indexed: 01/21/2023] Open
Abstract
In the mammalian brain, auditory brainstem nuclei are arranged topographically according to acoustic frequency responsiveness. During postnatal development, the axon initial segment (AIS) of principal neurons undergoes structural refinement depending on location along the tonotopic axis within the medial nucleus of the trapezoid body (MNTB). However, the molecular mechanisms underlying the structural refinement of the AIS along the tonotopic axis in the auditory brainstem have not been explored. We tested the hypothesis that brain-derived neurotrophic factor (BDNF) is a molecular mediator of the structural development of the MNTB in an activity-dependent manner. Using BDNF heterozygous mutant (BDNF+/- ) mice, we examined the impact of global BDNF reduction on structural and functional development of MNTB neurons by assessing AIS structure and associated intrinsic neuronal properties. BDNF reduction inhibits the structural and functional differentiation of principal neurons along the tonotopic axis in the MNTB. Augmented sound input during the critical period of development has been shown to enhance the structural refinement of the AIS of MNTB neurons. However, in BDNF +/- mice, MNTB neurons did not show this activity-dependent structural modification of the AIS following repeated sound stimulation. In addition, BDNF+/- mice lacked a defined isofrequency band of neuronal activity following exposure to 16 kHz sound, suggesting degradation of tonotopy. Taken together, structural development and functional refinement of auditory brainstem neurons require physiological levels of BDNF to establish proper tonotopic gradients.
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Affiliation(s)
| | - Jun Hee Kim
- Department of Cellular and Integrative Physiology, UT Health San Antonio, San Antonio, TX, United States
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The Type 2 Diabetes Factor Methylglyoxal Mediates Axon Initial Segment Shortening and Alters Neuronal Function at the Cellular and Network Levels. eNeuro 2021; 8:ENEURO.0201-21.2021. [PMID: 34531281 PMCID: PMC8496204 DOI: 10.1523/eneuro.0201-21.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 08/23/2021] [Accepted: 09/07/2021] [Indexed: 02/02/2023] Open
Abstract
Recent evidence suggests that alteration of axon initial segment (AIS) geometry (i.e., length or location along the axon) contributes to CNS dysfunction in neurological diseases. For example, AIS length is shorter in the prefrontal cortex of type 2 diabetic mice with cognitive impairment. To determine the key type 2 diabetes-related factor that produces AIS shortening we modified levels of insulin, glucose, or the reactive glucose metabolite methylglyoxal in cultures of dissociated cortices from male and female mice and quantified AIS geometry using immunofluorescent imaging of the AIS proteins AnkyrinG and βIV spectrin. Neither insulin nor glucose modification altered AIS length. Exposure to 100 but not 1 or 10 μm methylglyoxal for 24 h resulted in accumulation of the methylglyoxal-derived advanced glycation end-product hydroimidazolone and produced reversible AIS shortening without cell death. Methylglyoxal-evoked AIS shortening occurred in both excitatory and putative inhibitory neuron populations and in the presence of tetrodotoxin (TTX). In single-cell recordings resting membrane potential was depolarized at 0.5-3 h and returned to normal at 24 h. In multielectrode array (MEA) recordings methylglyoxal produced an immediate ∼300% increase in spiking and bursting rates that returned to normal within 2 min, followed by a ∼20% reduction of network activity at 0.5-3 h and restoration of activity to baseline levels at 24 h. AIS length was unchanged at 0.5-3 h despite the presence of depolarization and network activity reduction. Nevertheless, these results suggest that methylglyoxal could be a key mediator of AIS shortening and disruptor of neuronal function during type 2 diabetes.
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Adipose tissue-derived neurotrophic factor 3 regulates sympathetic innervation and thermogenesis in adipose tissue. Nat Commun 2021; 12:5362. [PMID: 34508100 PMCID: PMC8433218 DOI: 10.1038/s41467-021-25766-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 08/31/2021] [Indexed: 02/04/2023] Open
Abstract
Activation of brown fat thermogenesis increases energy expenditure and alleviates obesity. Sympathetic nervous system (SNS) is important in brown/beige adipocyte thermogenesis. Here we discover a fat-derived "adipokine" neurotrophic factor neurotrophin 3 (NT-3) and its receptor Tropomyosin receptor kinase C (TRKC) as key regulators of SNS growth and innervation in adipose tissue. NT-3 is highly expressed in brown/beige adipocytes, and potently stimulates sympathetic neuron neurite growth. NT-3/TRKC regulates a plethora of pathways in neuronal axonal growth and elongation. Adipose tissue sympathetic innervation is significantly increased in mice with adipocyte-specific NT-3 overexpression, but profoundly reduced in mice with TRKC haploinsufficiency (TRKC +/-). Increasing NT-3 via pharmacological or genetic approach promotes beige adipocyte development, enhances cold-induced thermogenesis and protects against diet-induced obesity (DIO); whereas TRKC + /- or SNS TRKC deficient mice are cold intolerant and prone to DIO. Thus, NT-3 is a fat-derived neurotrophic factor that regulates SNS innervation, energy metabolism and obesity.
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Plasmalogens regulate the AKT-ULK1 signaling pathway to control the position of the axon initial segment. Prog Neurobiol 2021; 205:102123. [PMID: 34302896 DOI: 10.1016/j.pneurobio.2021.102123] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 06/11/2021] [Accepted: 07/14/2021] [Indexed: 01/04/2023]
Abstract
The axon initial segment (AIS) is a specialized region in neurons that encompasses two essential functions, the generation of action potentials and the regulation of the axodendritic polarity. The mechanism controlling the position of the axon initial segment to allow plasticity and regulation of neuron excitability is unclear. Here we demonstrate that plasmalogens, the most abundant ether-phospholipid, are essential for the homeostatic positioning of the AIS. Plasmalogen deficiency is a hallmark of Rhizomelic Chondrodysplasia Punctata (RCDP) and Zellweger spectrum disorders, but Alzheimer's and Parkinson's disease, are also characterized by plasmalogen defects. Neurons lacking plasmalogens displaced the AIS to more distal positions and were characterized by reduced excitability. Treatment with a short-chain alkyl glycerol was able to rescue AIS positioning. Plasmalogen deficiency impaired AKT activation, and we show that inhibition of AKT phosphorylation at Ser473 and Thr308 is sufficient to induce a distal relocation of the AIS. Pathway analysis revealed that downstream of AKT, overtly active ULK1 mediates AIS repositioning. Rescuing the impaired AKT signaling pathway was able to normalize AIS position independently of the biochemical defect. These results unveil a previously unknown mechanism that couples the phospholipid composition of the neuronal membrane to the positional assembly of the AIS.
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Wei X, Wang L, Hua J, Jin XH, Ji F, Peng K, Zhou B, Yang J, Meng XW. Inhibiting BDNF/TrkB.T1 receptor improves resiniferatoxin-induced postherpetic neuralgia through decreasing ASIC3 signaling in dorsal root ganglia. J Neuroinflammation 2021; 18:96. [PMID: 33874962 PMCID: PMC8054387 DOI: 10.1186/s12974-021-02148-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 04/03/2021] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Postherpetic neuralgia (PHN) is a devastating complication after varicella-zoster virus infection. Brain-derived neurotrophic factor (BDNF) has been shown to participate in the pathogenesis of PHN. A truncated isoform of the tropomyosin receptor kinase B (TrkB) receptor TrkB.T1, as a high-affinity receptor of BDNF, is upregulated in multiple nervous system injuries, and such upregulation is associated with pain. Acid-sensitive ion channel 3 (ASIC3) is involved in chronic neuropathic pain, but its relation with BDNF/TrkB.T1 in the peripheral nervous system (PNS) during PHN is unclear. This study aimed to investigate whether BDNF/TrkB.T1 contributes to PHN through regulating ASIC3 signaling in dorsal root ganglia (DRGs). METHODS Resiniferatoxin (RTX) was used to induce rat PHN models. Mechanical allodynia was assessed by measuring the paw withdrawal thresholds (PWTs). Thermal hyperalgesia was determined by detecting the paw withdrawal latencies (PWLs). We evaluated the effects of TrkB.T1-ASIC3 signaling inhibition on the behavior, neuronal excitability, and inflammatory response during RTX-induced PHN. ASIC3 short hairpin RNA (shRNA) transfection was used to investigate the effect of exogenous BDNF on inflammatory response in cultured PC-12 cells. RESULTS RTX injection induced mechanical allodynia and upregulated the protein expression of BDNF, TrkB.T1, ASIC3, TRAF6, nNOS, and c-Fos, as well as increased neuronal excitability in DRGs. Inhibition of ASIC3 reversed the abovementioned effects of RTX, except for BDNF and TrkB.T1 protein expression. In addition, inhibition of TrkB.T1 blocked RTX-induced mechanical allodynia, activation of ASIC3 signaling, and hyperexcitability of neurons. RTX-induced BDNF upregulation was found in both neurons and satellite glia cells in DRGs. Furthermore, exogenous BDNF activated ASIC3 signaling, increased NO level, and enhanced IL-6, IL-1β, and TNF-α levels in PC-12 cells, which was blocked by shRNA-ASIC3 transfection. CONCLUSION These findings demonstrate that inhibiting BDNF/TrkB.T1 reduced inflammation, decreased neuronal hyperexcitability, and improved mechanical allodynia through regulating the ASIC3 signaling pathway in DRGs, which may provide a novel therapeutic target for patients with PHN.
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Affiliation(s)
- Xiang Wei
- Department of Anesthesiology and Pain Management, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, Jiangsu, China
| | - Lina Wang
- Department of Anesthesiology and Pain Management, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, Jiangsu, China
| | - Jie Hua
- Department of Anesthesiology and Pain Management, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, Jiangsu, China
| | - Xiao-Hong Jin
- Department of Anesthesiology and Pain Management, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, Jiangsu, China
| | - Fuhai Ji
- Department of Anesthesiology and Pain Management, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, Jiangsu, China
| | - Ke Peng
- Department of Anesthesiology and Pain Management, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, Jiangsu, China
| | - Bin Zhou
- Jiangsu Key Laboratory of Clinical Immunology, Soochow University, Suzhou, Jiangsu, China.,Jiangsu Key Laboratory of Gastrointestinal tumor Immunology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Jianping Yang
- Department of Anesthesiology and Pain Management, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, Jiangsu, China.
| | - Xiao-Wen Meng
- Department of Anesthesiology and Pain Management, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, Jiangsu, China.
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Wu Q, Chen J, Yue J, Ying X, Zhou Y, Chen X, Tu W, Lou X, Yang G, Zhou K, Jiang S. Electroacupuncture improves neuronal plasticity through the A2AR/cAMP/PKA signaling pathway in SNL rats. Neurochem Int 2021; 145:104983. [PMID: 33577869 DOI: 10.1016/j.neuint.2021.104983] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 01/05/2021] [Accepted: 02/02/2021] [Indexed: 12/11/2022]
Abstract
Improvements in neuronal plasticity are considered to be conducive to recovery from neuropathic pain. Electroacupuncture (EA) is regarded as an effective rehabilitation method for neuropathic pain. However, the effects and potential mechanism associated with EA-induced repair of hyperesthesia are not fully understood. Evidence has suggested that the adenosine A2A receptor (A2AR) and the cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) pathway play an important role in improving neuropathic pain. Here, we examined the function of EA in promoting neuronal plasticity in spinal nerve ligation (SNL) rats. The A2AR antagonist SCH58261, A2AR agonist 2-p-(2-carboxyethyl)phenethylamino-50-N-ethylcarboxamido adenosine HCl (CGS21680) and A2AR siRNA were used to confirm the relationship between A2AR and the cAMP/PKA pathway as well as the effects of A2AR on EA-induced improvements in neurobehavioral state and neuronal plasticity. Mechanical withdrawal threshold (MWT), thermal withdrawal latency (TWL), HE staining, Western blotting, RT-PCR, immunofluorescence, enzyme-linked immunosorbent assay, Nissl staining, silver staining, Golgi-Cox staining and transmission electron microscopy were used to evaluate the changes in neurobehavioral performance, protein expression, neuronal structure and dendrites/synapses. The results showed that EA and CGS21680 improved the behavioral performance, neuronal structure and dendritic/synaptic morphology of SNL rats, consistent with higher expression levels of A2AR, cAMP and PKA. In contrast to the positive effects of EA, SCH58261 inhibited dendritic growth and promoted dendritic spine/synaptic remodeling. In addition, the EA-induced improvement in neuronal plasticity was inhibited by SCH58261 and A2AR siRNA, consistent with lower expression levels of A2AR, cAMP and PKA, and worse behavioral performance. These results indicate that EA suppresses SNL-induced neuropathic pain by improving neuronal plasticity via upregulating the A2AR/cAMP/PKA signaling pathway.
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Affiliation(s)
- Qiaoyun Wu
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jie Chen
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jingjing Yue
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xinwang Ying
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Ye Zhou
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiaolong Chen
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Wenzhan Tu
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xinfa Lou
- Integrative & Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Guanhu Yang
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China.
| | - Kecheng Zhou
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China.
| | - Songhe Jiang
- Department of Physical Medicine and Rehabilitation, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China; Integrative & Optimized Medicine Research Center, China-USA Institute for Acupuncture and Rehabilitation, Wenzhou Medical University, Wenzhou, Zhejiang, China.
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Takahashi M, Sanchez JT. Effects of Neurotrophin-3 on Intrinsic Neuronal Properties at a Central Auditory Structure. Neurosci Insights 2020; 15:2633105520980442. [PMID: 33354669 PMCID: PMC7734498 DOI: 10.1177/2633105520980442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 11/23/2020] [Indexed: 11/15/2022] Open
Abstract
Neurotrophins, a class of growth factor proteins that control neuronal proliferation, morphology, and apoptosis, are found ubiquitously throughout the nervous system. One particular neurotrophin (NT-3) and its cognate tyrosine receptor kinase (TrkC) have recently received attention as a possible therapeutic target for synaptopathic sensorineural hearing loss. Additionally, research shows that NT-3-TrkC signaling plays a role in establishing the sensory organization of frequency topology (ie, tonotopic order) in the cochlea of the peripheral inner ear. However, the neurotrophic effects of NT-3 on central auditory properties are unclear. In this study we examined whether NT-3-TrkC signaling affects the intrinsic electrophysiological properties at a first-order central auditory structure in chicken, known as nucleus magnocellularis (NM). Here, the expression pattern of specific neurotrophins is well known and tightly regulated. By using whole-cell patch-clamp electrophysiology, we show that NT-3 application to brainstem slices does not affect intrinsic properties of high-frequency neuronal regions but had robust effects for low-frequency neurons, altering voltage-dependent potassium functions, action potential repolarization kinetics, and passive membrane properties. We suggest that NT-3 may contribute to the precise establishment and organization of tonotopy in the central auditory pathway by playing a specialized role in regulating the development of intrinsic neuronal properties of low-frequency NM neurons.
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Affiliation(s)
- Momoko Takahashi
- Roxelyn and Richard Pepper Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL, USA
| | - Jason Tait Sanchez
- Roxelyn and Richard Pepper Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL, USA
- Department of Neurobiology, Northwestern University, Evanston, IL, USA
- The Hugh Knowles Hearing Research Center, Northwestern University, Evanston, IL, USA
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Lee JW. Protonic conductor: better understanding neural resting and action potential. J Neurophysiol 2020; 124:1029-1044. [PMID: 32816602 DOI: 10.1152/jn.00281.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
With the employment of the transmembrane electrostatic proton localization theory with a new membrane potential equation, neural resting and action potential is now much better understood as the voltage contributed by the localized protons/cations at a neural liquid- membrane interface. Accordingly, the neural resting/action potential is essentially a protonic/cationic membrane capacitor behavior. It is now understood with a newly formulated action potential equation: when action potential is <0 (negative number), the localized protons/cations charge density at the liquid-membrane interface along the periplasmic side is >0 (positive number); when the action potential is >0, the concentration of the localized protons and localized nonproton cations is <0, indicating a "depolarization" state. The nonlinear curve of the localized protons/cations charge density in the real-time domain of an action potential spike appears as an inverse mirror image to the action potential. The newly formulated action potential equation provides biophysical insights for neuron electrophysiology, which may represent a complementary development to the classic Goldman-Hodgkin-Katz equation. With the use of the action potential equation, the biological significance of axon myelination is now also elucidated as to provide protonic insulation and prevent any ions both inside and outside of the neuron from interfering with the action potential signal, so that the action potential can quickly propagate along the axon with minimal (e.g., 40 times less) energy requirement.NEW & NOTEWORTHY The newly formulated action potential equation provides biophysical insights for neuron electrophysiology, which may represent a complementary development to the classic Goldman-Hodgkin-Katz equation. The nonlinear curve of the localized protons/cations charge density in the real-time domain of an action potential spike appears as an inverse mirror image to the action potential. The biological significance of axon myelination is now elucidated as to provide protonic insulation and prevent any ions from interfering with action potential signal.
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Affiliation(s)
- James Weifu Lee
- Department of Chemistry & Biochemistry, Old Dominion University, Norfolk, Virginia
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11
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Fan F, Tang Y, Dai H, Cao Y, Sun P, Chen Y, Chen A, Lin C. Blockade of BDNF signalling attenuates chronic visceral hypersensitivity in an IBS-like rat model. Eur J Pain 2020; 24:839-850. [PMID: 31976585 PMCID: PMC7154558 DOI: 10.1002/ejp.1534] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Revised: 01/13/2020] [Accepted: 01/14/2020] [Indexed: 12/14/2022]
Abstract
Background Irritable bowel syndrome (IBS) is a common functional disease characterized by chronic abdominal pain and changes in bowel movements. Effective therapy for visceral hypersensitivity in IBS patients remains challenging. This study investigated the roles of brain‐derived neurotrophic factor (BDNF) and tyrosine kinase receptor B (TrkB) and the effect of ANA‐12 (a selective antagonist of TrkB) on chronic visceral hypersensitivity in an IBS‐like rat model. Methods An IBS‐like rat model was established through neonatal maternal separation (NMS), and visceral hypersensitivity was assessed by electromyographic (EMG) responses of the abdominal external oblique muscles to colorectal distention (CRD). Different doses of ANA‐12 were injected intrathecally to investigate the effect of that drug on visceral hypersensitivity, and the open field test was performed to determine whether ANA‐12 had side effects on movement. Thoracolumbar spinal BDNF, TrkB receptor and Protein kinase Mζ (PKMζ) expression were measured to investigate their roles in chronic visceral hypersensitivity. Whole‐cell recordings were made from thoracolumbar superficial dorsal horn (SDH) neurons of lamina II. Results The expression of BDNF and TrkB was enhanced in the thoracolumbar spinal cord of the NMS animals. ANA‐12 attenuated visceral hypersensitivity without side effects on motricity in NMS rats. PKMζ expression significantly decreased after the administration of ANA‐12. The frequency of spontaneous excitatory postsynaptic currents (sEPSCs) increased in the thoracolumbar SDH neurons of lamina II in NMS rats. The amplitude and frequency of sEPSCs were reduced after perfusion with ANA‐12 in NMS rats. Conclusions Neonatal maternal separation caused visceral hypersensitivity and increased synaptic activity by activating BDNF‐TrkB‐PKMζ signalling in the thoracolumbar spinal cord of adult rats. PKMζ was able to potentiate AMPA receptor (AMPAR)‐mediated sEPSCs in NMS rats. ANA‐12 attenuated visceral hypersensitivity and synaptic activity by blocking BDNF/TrkB signalling in NMS rats. Significance ANA‐12 attenuates visceral hypersensitivity via BDNF‐TrkB‐PKMζ signalling and reduces synaptic activity through AMPARs in NMS rats. This knowledge suggests that ANA‐12 could represent an interesting novel therapeutic medicine for chronic visceral hypersensitivity.
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Affiliation(s)
- Fei Fan
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China.,Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative Diseases, Fujian Medical University, Fuzhou, China
| | - Ying Tang
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China
| | - Hengfen Dai
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China.,Affiliated Fuzhou First Hospital of Fujian Medical University, Fuzhou, China
| | - Yang Cao
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China
| | - Pei Sun
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China
| | - Yu Chen
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China
| | - Aiqin Chen
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China
| | - Chun Lin
- School of basic Medical Sciences, Laboratory of Pain Research, Fujian Medical University, Fuzhou, China
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12
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Zhu MY, Zhang DL, Zhou C, Chai Z. Mild Acidosis Protects Neurons during Oxygen-Glucose Deprivation by Reducing Loss of Mitochondrial Respiration. ACS Chem Neurosci 2019; 10:2489-2497. [PMID: 30835994 DOI: 10.1021/acschemneuro.8b00737] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Brain ischemia is often accompanied by brain acidosis and this acidosis can affect ischemic neuronal injury. Ischemic neuronal injury is initiated by a decrease in ATP production which mainly relies on mitochondrial oxidative phosphorylation. Ischemia often causes mitochondrial dysfunction, and acidosis has been found to affect mitochondrial function, suggesting that acidosis accompanying ischemia may influence neurons by targeting mitochondrial metabolism. However, the effects of acidosis on mitochondrial energy metabolism during ischemia lacks thorough investigation. Here, we found that mild acidosis significantly reduced neuronal death possibly by slowing the process of ATP deprivation during oxygen-glucose deprivation (OGD), an in vitro ischemic model. The maintaining of neuronal ATP depended on protecting mitochondrial ATP production. Further investigation of mitochondrial function revealed that mild acidosis alleviated OGD-induced collapse of mitochondrial membrane potentials as well as damage to respiratory function, at least in part by reducing impacts on complex I and II activities. Inhibition of complex I activity aggravated neuronal death, which suggests that the contribution of mild acidosis to maintaining complex I activity promoted neuronal survival during OGD. Our findings reveal maintaining mitochondrial respiration as a new possible protective mechanism of mild acidosis during ischemia, on neurons.
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Affiliation(s)
- Ming-Yue Zhu
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
| | - Dong-Liang Zhang
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
| | - Chen Zhou
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
| | - Zhen Chai
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
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13
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Aydin-Abidin S, Abidin İ. 7,8-Dihydroxyflavone potentiates ongoing epileptiform activity in mice brain slices. Neurosci Lett 2019; 703:25-31. [PMID: 30880161 DOI: 10.1016/j.neulet.2019.03.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 02/22/2019] [Accepted: 03/09/2019] [Indexed: 12/14/2022]
Abstract
In the central nervous system, Tropomyosin-receptor-kinase B (TrkB) signaling is involved in neuronal survival, differentiation as well as in regulation of synaptic transmission and excitability. As its powerful potential to modulate neuronal functions, TrkB pathway is an attractive target for novel drugs and treatment of common neurological disorders. 7,8-Dihydroxyflavone (DHF), a TrkB receptor agonist, has similar properties with neurotrophin Brain Derived Neurotropic Factor (BDNF). DHF is reported to have a number of beneficial effects in neuroprotection, against depression and improving learning and memory. However, the outcome of acute application of DHF on the excitability of neuronal circuits is not clear. Especially the effects of DHF on synchronized epileptiform activity are not known. In this study, we investigated whether DHF induces epileptiform activity in brain slices and DHF has any effect on already initiated epileptiform discharges. We used acute horizontal hippocampal-entorhinal cortex slices obtained from 30 to 35 days of mice. Extracellular field potential recordings were obtained from entorhinal cortex (EC) and hippocampus CA1 region. DHF did not initiate any epileptiform activity or abnormal discharges. However, DHF increased the frequency of 4 aminopyridine (4AP) induced ictal and interictal events in both EC and CA1. The duration of induced ictal charges were also prolonged upon DHF application. In a number of slices, both EC and CA1, DHF led to ictogenesis. These results suggest that the acute activation of TrkB by DHF has a powerful potential on synchronized neuronal discharges which should be considered in future therapeutical approaches.
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Affiliation(s)
- Selcen Aydin-Abidin
- Department of Biophysics, Faculty of Medicine, Karadeniz Technical University, Trabzon, Turkey.
| | - İsmail Abidin
- Department of Biophysics, Faculty of Medicine, Karadeniz Technical University, Trabzon, Turkey
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14
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Neuronal excitability and spontaneous synaptic transmission in the entorhinal cortex of BDNF heterozygous mice. Neurosci Lett 2018; 690:69-75. [PMID: 30316983 DOI: 10.1016/j.neulet.2018.10.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 09/21/2018] [Accepted: 10/10/2018] [Indexed: 02/04/2023]
Abstract
Brain Derived Neurotropic Factor (BDNF) is a neutrophic factor that is required for the normal neuronal development and function. BDNF is involved in regulation of synapses as well as neuronal excitability. Entorhinal Cortex (EC) is a key brain area involved in many physiological and pathological processes. In this study we investigated the effects of chronically reduced BDNF levels on layer 3 pyramidal neurons of EC. We aimed to assess the effects of reduced levels of BDNF on firing properties, spontaneous synaptic currents and excitation/inhibition balance from acute brain slices. Patch clamp recordings were obtained from pyramidal neurons of Entorhinal Cortex Layer 3. Findings of BDNF heterozygous (BDNF (+/-)) mice compared to their wild-type littermates at the age of 23-28 days. Action potential threshold was shifted (p = 0,002) to depolarized potentials and spike frequency was smaller in response to somatic current injection steps in BDNF (+/-) mice. Spontaneous synaptic currents were also affected. sEPSC amplitude (p = 0,009), sIPSC frequency (p = 0,001) and sIPSC amplitudes (p = 0,023) were reduced in BDNF (+/-). Decay times of sIPSCs were longer in BDNF (+/-) (p = 0,014). Calculated balance of excitatory/inhibitory balance was shifted in the favor of excitation in BDNF (+/-) mice (p = 0,01). These findings suggest that reductions in concentrations of BDNF results in altered status of excitability and excitation/inhibition imbalance. However, these differences observed in BDNF (+/-) seem to have opposing effects on neuronal activity.
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15
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Yermakov LM, Drouet DE, Griggs RB, Elased KM, Susuki K. Type 2 Diabetes Leads to Axon Initial Segment Shortening in db/db Mice. Front Cell Neurosci 2018; 12:146. [PMID: 29937715 PMCID: PMC6002488 DOI: 10.3389/fncel.2018.00146] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 05/14/2018] [Indexed: 01/09/2023] Open
Abstract
Cognitive and mood impairments are common central nervous system complications of type 2 diabetes, although the neuronal mechanism(s) remains elusive. Previous studies focused mainly on neuronal inputs such as altered synaptic plasticity. Axon initial segment (AIS) is a specialized functional domain within neurons that regulates neuronal outputs. Structural changes of AIS have been implicated as a key pathophysiological event in various psychiatric and neurological disorders. Here we evaluated the structural integrity of the AIS in brains of db/db mice, an established animal model of type 2 diabetes associated with cognitive and mood impairments. We assessed the AIS before (5 weeks of age) and after (10 weeks) the development of type 2 diabetes, and after daily exercise treatment of diabetic condition. We found that the development of type 2 diabetes is associated with significant AIS shortening in both medial prefrontal cortex and hippocampus, as evident by immunostaining of the AIS structural protein βIV spectrin. AIS shortening occurs in the absence of altered neuronal and AIS protein levels. We found no change in nodes of Ranvier, another neuronal functional domain sharing a molecular organization similar to the AIS. This is the first study to identify AIS alteration in type 2 diabetes condition. Since AIS shortening is known to lower neuronal excitability, our results may provide a new avenue for understanding and treating cognitive and mood impairments in type 2 diabetes.
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Affiliation(s)
- Leonid M Yermakov
- Department of Neuroscience, Cell Biology, and Physiology, Boonshoft School of Medicine, Wright State University, Dayton, OH, United States
| | - Domenica E Drouet
- Department of Neuroscience, Cell Biology, and Physiology, Boonshoft School of Medicine, Wright State University, Dayton, OH, United States
| | - Ryan B Griggs
- Department of Neuroscience, Cell Biology, and Physiology, Boonshoft School of Medicine, Wright State University, Dayton, OH, United States
| | - Khalid M Elased
- Department of Pharmacology and Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, OH, United States
| | - Keiichiro Susuki
- Department of Neuroscience, Cell Biology, and Physiology, Boonshoft School of Medicine, Wright State University, Dayton, OH, United States
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16
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The Axon Initial Segment: An Updated Viewpoint. J Neurosci 2018; 38:2135-2145. [PMID: 29378864 DOI: 10.1523/jneurosci.1922-17.2018] [Citation(s) in RCA: 164] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Revised: 01/20/2018] [Accepted: 01/25/2018] [Indexed: 12/20/2022] Open
Abstract
At the base of axons sits a unique compartment called the axon initial segment (AIS). The AIS generates and shapes the action potential before it is propagated along the axon. Neuronal excitability thus depends crucially on the AIS composition and position, and these adapt to developmental and physiological conditions. The AIS also demarcates the boundary between the somatodendritic and axonal compartments. Recent studies have brought insights into the molecular architecture of the AIS and how it regulates protein trafficking. This Viewpoints article summarizes current knowledge about the AIS and highlights future challenges in understanding this key actor of neuronal physiology.
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17
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Höfflin F, Jack A, Riedel C, Mack-Bucher J, Roos J, Corcelli C, Schultz C, Wahle P, Engelhardt M. Heterogeneity of the Axon Initial Segment in Interneurons and Pyramidal Cells of Rodent Visual Cortex. Front Cell Neurosci 2017; 11:332. [PMID: 29170630 PMCID: PMC5684645 DOI: 10.3389/fncel.2017.00332] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 10/09/2017] [Indexed: 11/13/2022] Open
Abstract
The microdomain that orchestrates action potential initiation in neurons is the axon initial segment (AIS). It has long been considered to be a rather homogeneous domain at the very proximal axon hillock with relatively stable length, particularly in cortical pyramidal cells. However, studies in other brain regions paint a different picture. In hippocampal CA1, up to 50% of axons emerge from basal dendrites. Further, in about 30% of thick-tufted layer V pyramidal neurons in rat somatosensory cortex, axons have a dendritic origin. Consequently, the AIS is separated from the soma. Recent in vitro and in vivo studies have shown that cellular excitability is a function of AIS length/position and somatodendritic morphology, undermining a potentially significant impact of AIS heterogeneity for neuronal function. We therefore investigated neocortical axon morphology and AIS composition, hypothesizing that the initial observation of seemingly homogeneous AIS is inadequate and needs to take into account neuronal cell types. Here, we biolistically transfected cortical neurons in organotypic cultures to visualize the entire neuron and classify cell types in combination with immunolabeling against AIS markers. Using confocal microscopy and morphometric analysis, we investigated axon origin, AIS position, length, diameter as well as distance to the soma. We find a substantial AIS heterogeneity in visual cortical neurons, classified into three groups: (I) axons with somatic origin with proximal AIS at the axon hillock; (II) axons with somatic origin with distal AIS, with a discernible gap between the AIS and the soma; and (III) axons with dendritic origin (axon-carrying dendrite cell, AcD cell) and an AIS either starting directly at the axon origin or more distal to that point. Pyramidal cells have significantly longer AIS than interneurons. Interneurons with vertical columnar axonal projections have significantly more distal AIS locations than all other cells with their prevailing phenotype as an AcD cell. In contrast, neurons with perisomatic terminations display most often an axon originating from the soma. Our data contribute to the emerging understanding that AIS morphology is highly variable, and potentially a function of the cell type.
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Affiliation(s)
- Felix Höfflin
- Institute of Neuroanatomy, Medical Faculty Mannheim, Center for Biomedicine and Medical Technology Mannheim (CBTM), Heidelberg University, Heidelberg, Germany
| | - Alexander Jack
- Developmental Neurobiology, Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
| | - Christian Riedel
- Developmental Neurobiology, Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
| | - Julia Mack-Bucher
- Live Cell Imaging Core Mannheim (LIMA), Medical Faculty Mannheim, Center for Biomedicine and Medical Technology Mannheim (CBTM), Heidelberg University, Heidelberg, Germany
| | - Johannes Roos
- Institute of Neuroanatomy, Medical Faculty Mannheim, Center for Biomedicine and Medical Technology Mannheim (CBTM), Heidelberg University, Heidelberg, Germany
| | - Corinna Corcelli
- Institute of Neuroanatomy, Medical Faculty Mannheim, Center for Biomedicine and Medical Technology Mannheim (CBTM), Heidelberg University, Heidelberg, Germany
| | - Christian Schultz
- Institute of Neuroanatomy, Medical Faculty Mannheim, Center for Biomedicine and Medical Technology Mannheim (CBTM), Heidelberg University, Heidelberg, Germany
| | - Petra Wahle
- Developmental Neurobiology, Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
| | - Maren Engelhardt
- Institute of Neuroanatomy, Medical Faculty Mannheim, Center for Biomedicine and Medical Technology Mannheim (CBTM), Heidelberg University, Heidelberg, Germany
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18
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Ros O, Nicol X. Linking activity-dependent control of axon initial segment structure to the cytoskeleton (Commentary on Evans et al. (2017)). Eur J Neurosci 2017; 46:1749-1750. [PMID: 28612392 DOI: 10.1111/ejn.13619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Oriol Ros
- Sorbonne Universités, UPMC University Paris 06, UMR_S 968, Institut de la Vision, Paris, France.,CNRS, UMR_7210, Paris, France.,INSERM, UMR_S 968, Paris, France
| | - Xavier Nicol
- Sorbonne Universités, UPMC University Paris 06, UMR_S 968, Institut de la Vision, Paris, France.,CNRS, UMR_7210, Paris, France.,INSERM, UMR_S 968, Paris, France
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