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Hsu HH, Lee AH, Tai SH, Chen LY, Huang SY, Chen YY, Hung YC, Wu TS, Lee EJ. Viscolin-mediated antiapoptotic and neuroprotective effects in cortical neurons exposed to oxygen-glucose deprivation and rats subjected to transient focal cerebral ischemia. Neurol Res 2024:1-11. [PMID: 39033031 DOI: 10.1080/01616412.2024.2381381] [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: 01/04/2024] [Accepted: 07/14/2024] [Indexed: 07/23/2024]
Abstract
OBJECTIVE Previously, we have successfully purified and synthesized viscolin, an agent derived from Viscum coloratum extract, which has shown significant potential in the treatment of stroke. Our study aimed to evaluate the neuroprotective effects of viscolin. METHODS We first assessed the cytotoxicity of viscolin on primary neuronal cultures and determined its antioxidant and radical scavenging properties. Subsequently, we identified the optimal dose-response of viscolin in protecting against glutamate-induced neurotoxicity. RESULTS Our results demonstrated that viscolin at a concentration of 10 μM effectively reduced neuronal cell death up to 6 hours after glutamate-induced neurotoxicity. Additionally, we investigated the therapeutic window of opportunity and the potential of viscolin in preventing necrotic and apoptotic damage in cultured neurons exposed to oxygen glucose deprivation-induced neurotoxicity. Our findings showed that viscolin treatment significantly reduced DNA breakage, prevented the release of cytochrome c from mitochondria to cytosol, increased the expression of anti-apoptotic protein Bcl-2, decreased the expression of pro-apoptotic protein Bax, and reduced the number of TUNEL-positive cells. Additionally, our in vivo investigation demonstrated a reduction in brain infarction following middle cerebral artery occlusion. CONCLUSION Viscolin has potential utility as a therapeutic agent in the treatment of stroke.
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Affiliation(s)
- Hao-Hsiang Hsu
- Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Ai-Hua Lee
- Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Shih-Huang Tai
- Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Liang-Yi Chen
- Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Sheng-Yang Huang
- Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Yi-Yun Chen
- Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Yu-Chang Hung
- Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Tian-Shung Wu
- School of Pharmacy, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - E-Jian Lee
- Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, Tainan, Taiwan
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Tai SH, Chao LC, Huang SY, Lin HW, Lee AH, Chen YY, Lee EJ. Nicotinamide Deteriorates Post-Stroke Immunodepression Following Cerebral Ischemia-Reperfusion Injury in Mice. Biomedicines 2023; 11:2145. [PMID: 37626642 PMCID: PMC10452067 DOI: 10.3390/biomedicines11082145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 07/26/2023] [Accepted: 07/28/2023] [Indexed: 08/27/2023] Open
Abstract
(1) Background: Inducing experimental stroke leads to biphasic immune responses, where the early activation of immune functions is followed by severe immunosuppression accompanied by spleen and thymus atrophy. Nicotinamide, a water-soluble B-group vitamin, is a known neuroprotectant against brain ischemia in animal models. We examined the effect of nicotinamide on the central and peripheral immune response in experimental stroke models. (2) Methods: Nicotinamide (500 mg/kg) or saline was intravenously administered to C57BL/6 mice during reperfusion after transiently occluding the middle cerebral artery or after LPS injection. On day 3, the animals were examined for behavioral performance and were then sacrificed to assess brain infarction, blood-brain barrier (BBB) integrity, and the composition of immune cells in the brain, thymus, spleen, and blood using flow cytometry. (3) Results: Nicotinamide reduced brain infarction and microglia/macrophage activation following MCAo (p < 0.05). Similarly, in LPS-injected mice, microglia/macrophage activation was decreased upon treatment with nicotinamide (p < 0.05), suggesting a direct inhibitory effect of nicotinamide on microglia/macrophage activation. Nicotinamide decreased the infiltration of neutrophils into the brain parenchyma and ameliorated Evans blue leakage (p < 0.05), suggesting that a decreased infiltration of neutrophils could, at least partially, be the result of a more integrated BBB structure following nicotinamide treatment. Our studies also revealed that administering nicotinamide led to retarded B-cell maturation in the spleen and subsequently decreased circulating B cells in the thymus and bloodstream (p < 0.05). (4) Conclusions: Cumulatively, nicotinamide decreased brain inflammation caused by ischemia-reperfusion injury, which was mediated by a direct anti-inflammatory effect of nicotinamide and an indirect protective effect on BBB integrity. Administering nicotinamide following brain ischemia resulted in a decrease in circulating B cells. This warrants attention with respect to future clinical applications.
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Affiliation(s)
| | | | | | | | | | | | - E-Jian Lee
- Neurophysiology Laboratory, Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 70403, Taiwan
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3
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Tu X, Li X, Zhu H, Kuang X, Si X, Zou S, Hao S, Huang Y, Xiao J. Unilateral cerebral ischemia induces morphological changes in the layer V projection neurons of the contralateral hemisphere. Neurosci Res 2022; 182:41-51. [PMID: 35777459 DOI: 10.1016/j.neures.2022.06.007] [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: 01/11/2022] [Revised: 06/22/2022] [Accepted: 06/26/2022] [Indexed: 10/17/2022]
Abstract
Decreased blood flow to the brain causes stroke and damage to neuronal networks. Neuronal damage occurs not only in the infarct core but also in areas away from the infarcts. This study was aimed to assess alterations of the cortical projection neurons that were distantly connected with the infarcts. Unilateral cortical ischemia was generated by middle cerebral artery occlusion in the right somatosensory cortex. Pre-labeled thalamocortical neurons disappeared, whereas contralateral callosal projection neurons survived 48 h post-ischemia. The unilateral ischemia increased the total length, segment length and the spine volume of dendrites from layer V callosal neurons in the homotopic cortex of the contralateral hemisphere. The morphological remolding of the contralateral cortical neurons cannot be reproduced by the spinal cord hemisection that cuts axons of corticospinal projection neurons of layer V. The data suggest that the retrograde degeneration of axons may not account for the early morphological changes in the contralateral cortex. We hypothesize that the loss of innervations from the ischemic cortex may bring in adaptive changes to the connected neurons, and adult cortical neurons can adjust their morphology to meet the reduction of synaptic inputs. This study may improve our understanding of the re-organization of cortical circuits following focal cerebral ischemia and help the development of new treatments designed to minimize the disability associated with stroke.
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Affiliation(s)
- XiaoMeng Tu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, PR China; State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou, Zhejiang, PR China
| | - Xue Li
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, PR China; State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou, Zhejiang, PR China
| | - Hao Zhu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, PR China; State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou, Zhejiang, PR China
| | - Xiuli Kuang
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, PR China; State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou, Zhejiang, PR China
| | - Xiang Si
- Department of Ophthalmology, Anhui Provincial Hospital, Hefei, Anhui, PR China
| | - Shimin Zou
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, PR China; State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou, Zhejiang, PR China
| | - Shishuai Hao
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, PR China; State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou, Zhejiang, PR China
| | - Yang Huang
- Department of Orthopedics, Taizhou Municipal Hospital, Taizhou, Zhejiang, PRChina.
| | - Jian Xiao
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, PR China; State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou, Zhejiang, PR China.
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4
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Tai SH, Huang SY, Chao LC, Lin YW, Huang CC, Wu TS, Shan YS, Lee AH, Lee EJ. Lithium upregulates growth-associated protein-43 (GAP-43) and postsynaptic density-95 (PSD-95) in cultured neurons exposed to oxygen-glucose deprivation and improves electrophysiological outcomes in rats subjected to transient focal cerebral ischemia following a long-term recovery period. Neurol Res 2022; 44:870-878. [PMID: 35348035 DOI: 10.1080/01616412.2022.2056817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVES Lithium has numerous neuroplastic and neuroprotective effects in patients with stroke. Here, we evaluated whether delayed and short-term lithium treatment reduces brain infarction volume and improves electrophysiological and neurobehavioral outcomes following long-term recovery after cerebral ischemia and the possible contributions of lithium-mediated mechanisms of neuroplasticity. METHODS Male Sprague Dawley rats were subjected to right middle cerebral artery occlusion for 90 min, followed by 28 days of recovery. Lithium chloride (1 mEq/kg) or vehicle was administered via intraperitoneal infusion once per day at 24 h after reperfusion onset. Neurobehavioral outcomes and somatosensory evoked potentials (SSEPs) were examined before and 28 days after ischemia-reperfusion. Brain infarction was assessed using Nissl staining. Primary cortical neuron cultures were exposed to oxygen-glucose deprivation (OGD) and treated with 2 or 20 μM lithium for 24 or 48 h; subsequent brain-derived neurotrophic factor (BDNF), growth-associated protein-43 (GAP-43), postsynaptic density-95 (PSD-95), and synaptosomal-associated protein-25 (SNAP-25) levels were analyzed using western blotting. RESULTS Compared to controls, lithium significantly reduced infarction volume in the ischemic brain and improved electrophysiological and neurobehavioral outcomes at 28 days post-insult. In cultured cortical neurons, BDNF, GAP-43, and PSD-95 expression were enhanced by 24- and 48-h treatment with lithium after OGD. CONCLUSION Lithium upregulates BDNF, GAP-43, and PSD-95, which partly accounts for its improvement of neuroplasticity and provision of long-term neuroprotection in the ischemic brain.Abbreviations: BDNF: brain-derived neurotrophic factor; ECM: extracellular matrix; EDTA: ethylenediaminetetraacetic acid; GAP-43: growth-associated protein-43; GSK-3β: glycogen synthase kinase-3β; HBSS: Hank's balanced salt solution; LCBF: local cortical blood perfusion; LDF: laser-Doppler flowmetry; MCAO: middle cerebral artery occlusion; MMP: matrix metalloproteinase; NMDA: N-methyl-D-aspartate; NMDAR: N-methyl-D-aspartate receptor; OCT: optimal cutting temperature compound; OGD: oxygen-glucose deprivation; PSD-95: postsynaptic density-95; SDS: sodium dodecyl sulfate; SNAP-25: synaptosomal-associated protein-25; SSEP: somatosensory evoked potential.
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Affiliation(s)
- Shih-Huang Tai
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Neurophysiology Laboratory, Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Sheng-Yang Huang
- Neurophysiology Laboratory, Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Liang-Chun Chao
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Neurophysiology Laboratory, Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yu-Wen Lin
- Neurophysiology Laboratory, Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chien-Chih Huang
- Neurophysiology Laboratory, Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Tian-Shung Wu
- School of Pharmacy, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yan-Shen Shan
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Ai-Hua Lee
- Neurophysiology Laboratory, Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - E-Jian Lee
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Neurophysiology Laboratory, Neurosurgical Service, Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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Du H, Xu Y, Zhu L. Role of Semaphorins in Ischemic Stroke. Front Mol Neurosci 2022; 15:848506. [PMID: 35350431 PMCID: PMC8957939 DOI: 10.3389/fnmol.2022.848506] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 02/17/2022] [Indexed: 12/12/2022] Open
Abstract
Ischemic stroke is one of the major causes of neurological morbidity and mortality in the world. Although the management of ischemic stroke has been improved significantly, it still imposes a huge burden on the health and property. The integrity of the neurovascular unit (NVU) is closely related with the prognosis of ischemic stroke. Growing evidence has shown that semaphorins, a family of axon guidance cues, play a pivotal role in multiple pathophysiological processes in NVU after ischemia, such as regulating the immune system, angiogenesis, and neuroprotection. Modulating the NVU function via semaphorin signaling has a potential to develop a novel therapeutic strategy for ischemic stroke. We, therefore, review recent progresses on the role of semphorin family members in neurons, glial cells and vasculature after ischemic stroke.
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Affiliation(s)
- Huaping Du
- Department of Neurology, Suzhou Ninth Hospital Affiliated to Soochow University, Suzhou, China
| | - Yuan Xu
- Department of Neurology, Suzhou Ninth Hospital Affiliated to Soochow University, Suzhou, China
| | - Li Zhu
- Department of Neurology, Suzhou Ninth Hospital Affiliated to Soochow University, Suzhou, China
- Suzhou Key Laboratory of Thrombosis and Vascular Biology, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Collaborative Innovation Center of Hematology of Jiangsu Province, National Clinical Research Center for Hematologic Diseases, Cyrus Tang Medical Institute, Soochow University, Suzhou, China
- *Correspondence: Li Zhu,
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Li W, Zhang L, Xu Q, Yang W, Zhao J, Ren Y, Yu Z, Ma L. Taxifolin Alleviates DSS-Induced Ulcerative Colitis by Acting on Gut Microbiome to Produce Butyric Acid. Nutrients 2022; 14:nu14051069. [PMID: 35268045 PMCID: PMC8912346 DOI: 10.3390/nu14051069] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 02/25/2022] [Accepted: 02/28/2022] [Indexed: 01/27/2023] Open
Abstract
Taxifolin is a bioflavonoid which has been used to treat Inflammatory Bowel Disease. However, taxifolin on DSS-induced colitis and gut health is still unclear. Here, we studied the effect of taxifolin on DSS-induced intestinal mucositis in mice. We measured the degree of intestinal mucosal injury and inflammatory response in DSS treated mice with or without taxifolin administration and studied the changes of fecal metabolites and intestinal microflora using 16S rRNA. The mechanism was further explored by fecal microbiota transplantation. The results showed that the weight loss and diarrhea score of the mice treated with taxifolin decreased in DSS-induced mice and longer colon length was displayed after taxifolin supplementation. Meanwhile, the expression of GPR41 and GPR43 in the colon was significantly increased by taxifolin treatment. Moreover, the expression of TNF-α, IL-1β, and IL-6 in colon tissue was inhibited by taxifolin treatment. The fecal metabolism pattern changed significantly after DSS treatment, which was reversed by taxifolin treatment. Importantly, taxifolin significantly increased the levels of butyric acid and isobutyric acid in the feces of DSS-treated mice. In terms of gut flora, taxifolin reversed the changes of Akkermansia, and further decreased uncultured_bacterium_f_Muribaculaceae. Fecal transplantation from taxifolin-treated mice showed a lower diarrhea score, reduced inflammatory response in the colon, and reduced intestinal mucosal damage, which may be related to the increased level of butyric acid in fecal metabolites. In conclusion, this study provides evidence that taxifolin can ameliorate DSS-induced colitis by altering gut microbiota to increase the production of SCFAs.
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Affiliation(s)
| | | | | | | | | | | | | | - Libao Ma
- Correspondence: ; Tel.: +86-13317192322
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7
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Tai SH, Chao LC, Huang TY, Chang CC, Huang SY, Wu TS, Lee EJ. Short-term lithium treatment protects the brain against ischemia-reperfusion injury by enhancing the neuroplasticity of cortical neurons. Neurol Res 2021; 44:128-138. [PMID: 34396932 DOI: 10.1080/01616412.2021.1965427] [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] [Indexed: 10/20/2022]
Abstract
OBJECTIVES Lithium exerts a broad neuroprotective effect on the brain. This study examined whether lithium exerts therapeutic effects on stroke by restoring neural connections at the ischemic core of cortices post brain insult. METHODS We treated rats with lithium or vehicle (saline) every 24 h for the first 72 h, starting at the beginning of reperfusion after inducing middle cerebral artery occlusion (MCAO) in rats. Somatosensory evoked potential (SSEP) recording and behavioral testing were employed to evaluate the beneficial effects of lithium treatment. To examine the effects of lithium-induced neuroplasticity, we evaluated the dendritic morphology in cortex pyramidal cells and the primary neuronal cell culture that underwent brain insults and oxygen and glucose deprivation (OGD), respectively. RESULTS The results demonstrated that rats subjected to MCAO had prolonged N1 latency and a decreased N1/P1 amplitude at the ipsilateral cortex. Four doses of lithium reduced the brain infarction volume and enhanced the SSEP amplitude. The results of neurobehavioral tests demonstrated that lithium treatment improved sensory function, as demonstrated by improved 28-point clinical scale scores. In vitro study results showed that lithium treatment increased the dendritic lengths and branches of cultured neurons and reversed the suppressive effects of OGD. The in vivo study results indicated that lithium treatment increased cortical spine density in various layers and resulted in the development of the dendritic structure in the contralateral hemisphere. CONCLUSION Our study confirmed that neuroplasticity in cortical neurons is crucial for lithium-induced brain function 50 recovery after brain ischemia.
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Affiliation(s)
- Shih-Huang Tai
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Neurophysiology Laboratory and Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Liang-Chun Chao
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Neurophysiology Laboratory and Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Tung-Yi Huang
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Che-Chao Chang
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Sheng-Yang Huang
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Tian-Shung Wu
- School of Pharmacy, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - E-Jian Lee
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Neurophysiology Laboratory and Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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8
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Adaptive Immune Cells Link Microbial Metabolites to Stroke Recovery. J Neurosci 2020; 40:5344-5346. [PMID: 32641452 DOI: 10.1523/jneurosci.0634-20.2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 05/15/2020] [Accepted: 06/04/2020] [Indexed: 11/21/2022] Open
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Narayanan SN, Bairy LK, Srinivasamurthy SK. Determining factors for optimal neuronal and glial Golgi-Cox staining. Histochem Cell Biol 2020; 154:431-448. [PMID: 32533234 DOI: 10.1007/s00418-020-01891-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/30/2020] [Indexed: 11/29/2022]
Abstract
Golgi staining allows for the analysis of neuronal arborisations and connections and is considered a powerful tool in basic and clinical neuroscience. The fundamental rules for improving neuronal staining using the Golgi-Cox method are not fully understood; both intrinsic and extrinsic factors may control the staining process. Therefore, various conditions were tested to improve the Golgi-Cox protocol for vibratome-cut rat brain sections. Optimal staining of cortical neurons was achieved after 72 h of impregnation. Well-stained neurons in both cortical and subcortical structures were observed after 96 h of impregnation. The dendritic arborisation pattern of cortical neurons derived from the 72-h impregnation group was comparable to those of the 96 and 168-h impregnation groups. The entire brain was stained well when the pH of the Golgi-Cox solution was 6.5 and that of the sodium carbonate solution was 11.2. Lack of brain perfusion or perfusion with 0.9% NaCl did not influence optimal neuronal staining. Perfusion with 37% formaldehyde, followed by impregnation, only resulted in glial staining, but perfusion with 4% formaldehyde facilitated both glial and neuronal staining. Whole brains required longer impregnation times for better staining. Although every factor had a role in determining optimal neuronal staining, impregnation time and the pH of staining solutions were key factors among them. This modified Golgi-Cox protocol provides a simple and economical procedure to stain both neurons and glia separately.
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Affiliation(s)
- Sareesh Naduvil Narayanan
- Department of Physiology, RAK College of Medical Sciences, RAK Medical and Health Sciences University, PO Box 11172, Ras Al Khaimah, United Arab Emirates.
| | - Laxminarayana Kurady Bairy
- Department of Pharmacology, RAK College of Medical Sciences, RAK Medical and Health Sciences University, PO Box 11172, Ras Al Khaimah, United Arab Emirates
| | - Suresh Kumar Srinivasamurthy
- Department of Pharmacology, RAK College of Medical Sciences, RAK Medical and Health Sciences University, PO Box 11172, Ras Al Khaimah, United Arab Emirates
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Hu J, Li C, Hua Y, Liu P, Gao B, Wang Y, Bai Y. Constraint-induced movement therapy improves functional recovery after ischemic stroke and its impacts on synaptic plasticity in sensorimotor cortex and hippocampus. Brain Res Bull 2020; 160:8-23. [PMID: 32298779 DOI: 10.1016/j.brainresbull.2020.04.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 03/12/2020] [Accepted: 04/06/2020] [Indexed: 01/28/2023]
Abstract
Constraint-induced movement therapy (CIMT) has proven to be an effective way to restore functional deficits following stroke in human and animal studies, but its underlying neural plasticity mechanism remains unknown. Accumulating evidence indicates that rehabilitation after stroke is closely associated with synaptic plasticity. We therefore investigated the impact of CIMT on synaptic plasticity in ipsilateral and contralateral brain of rats following stroke. Rats were subjected to 90 minutes of transient middle cerebral artery occlusion (MCAO). CIMT was performed from 7 days after stroke and lasted for two weeks. Modified Neurology Severity Score (mNSS) and the ladder rung walking task tests were conducted at 7,14 and 21 days after stroke. Golgi-Cox staining was used to observe the plasticity changes of dendrites and dendritic spines. The expression of glutamate receptors (GluR1, GluR2 and NR1) were examined by western blot. Our data suggest that the dendrites and dendritic spines are damaged to varying degrees in bilateral sensorimotor cortex and hippocampus after acute stroke. CIMT treatment enhances the plasticity of dendrites and dendritic spines in the ipsilateral and contralateral sensorimotor cortex, increases the expression of synaptic GluR2 in ipsilateral sensorimotor cortex, which may be mechanisms for CIMT to improve functional recovery after ischemic stroke.
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Affiliation(s)
- Jian Hu
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Ce Li
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Yan Hua
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Peile Liu
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Beiyao Gao
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Yuyuan Wang
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Yulong Bai
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China.
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11
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Sadler R, Cramer JV, Heindl S, Kostidis S, Betz D, Zuurbier KR, Northoff BH, Heijink M, Goldberg MP, Plautz EJ, Roth S, Malik R, Dichgans M, Holdt LM, Benakis C, Giera M, Stowe AM, Liesz A. Short-Chain Fatty Acids Improve Poststroke Recovery via Immunological Mechanisms. J Neurosci 2020; 40:1162-1173. [PMID: 31889008 PMCID: PMC6989004 DOI: 10.1523/jneurosci.1359-19.2019] [Citation(s) in RCA: 195] [Impact Index Per Article: 48.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 11/25/2019] [Accepted: 12/03/2019] [Indexed: 01/05/2023] Open
Abstract
Recovery after stroke is a multicellular process encompassing neurons, resident immune cells, and brain-invading cells. Stroke alters the gut microbiome, which in turn has considerable impact on stroke outcome. However, the mechanisms underlying gut-brain interaction and implications for long-term recovery are largely elusive. Here, we tested the hypothesis that short-chain fatty acids (SCFAs), key bioactive microbial metabolites, are the missing link along the gut-brain axis and might be able to modulate recovery after experimental stroke. SCFA supplementation in the drinking water of male mice significantly improved recovery of affected limb motor function. Using in vivo wide-field calcium imaging, we observed that SCFAs induced altered contralesional cortex connectivity. This was associated with SCFA-dependent changes in spine and synapse densities. RNA sequencing of the forebrain cortex indicated a potential involvement of microglial cells in contributing to the structural and functional remodeling. Further analyses confirmed a substantial impact of SCFAs on microglial activation, which depended on the recruitment of T cells to the infarcted brain. Our findings identified that microbiota-derived SCFAs modulate poststroke recovery via effects on systemic and brain resident immune cells.SIGNIFICANCE STATEMENT Previous studies have shown a bidirectional communication along the gut-brain axis after stroke. Stroke alters the gut microbiota composition, and in turn, microbiota dysbiosis has a substantial impact on stroke outcome by modulating the immune response. However, until now, the mediators derived from the gut microbiome affecting the gut-immune-brain axis and the molecular mechanisms involved in this process were unknown. Here, we demonstrate that short-chain fatty acids, fermentation products of the gut microbiome, are potent and proregenerative modulators of poststroke neuronal plasticity at various structural levels. We identified that this effect was mediated via circulating lymphocytes on microglial activation. These results identify short-chain fatty acids as a missing link along the gut-brain axis and as a potential therapeutic to improve recovery after stroke.
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Affiliation(s)
- Rebecca Sadler
- Institute for Stroke and Dementia Research, University Hospital, Ludwig-Maximilians-University LMU, 81377, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), 81377, Munich, Germany
| | - Julia V Cramer
- Institute for Stroke and Dementia Research, University Hospital, Ludwig-Maximilians-University LMU, 81377, Munich, Germany
| | - Steffanie Heindl
- Institute for Stroke and Dementia Research, University Hospital, Ludwig-Maximilians-University LMU, 81377, Munich, Germany
| | - Sarantos Kostidis
- Leiden University Medical Center, Center for Proteomics & Metabolomics, 2300 RC Leiden, The Netherlands
| | - Dene Betz
- Department of Neurology and Neurotherapeutics, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Kielen R Zuurbier
- Department of Neurology and Neurotherapeutics, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Bernd H Northoff
- Institute of Laboratory Medicine, University Hospital, Ludwig-Maximilians-University LMU, 81377, Munich, Germany, and
| | - Marieke Heijink
- Leiden University Medical Center, Center for Proteomics & Metabolomics, 2300 RC Leiden, The Netherlands
| | - Mark P Goldberg
- Department of Neurology and Neurotherapeutics, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Erik J Plautz
- Department of Neurology and Neurotherapeutics, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Stefan Roth
- Institute for Stroke and Dementia Research, University Hospital, Ludwig-Maximilians-University LMU, 81377, Munich, Germany
| | - Rainer Malik
- Institute for Stroke and Dementia Research, University Hospital, Ludwig-Maximilians-University LMU, 81377, Munich, Germany
| | - Martin Dichgans
- Institute for Stroke and Dementia Research, University Hospital, Ludwig-Maximilians-University LMU, 81377, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), 81377, Munich, Germany
| | - Lesca M Holdt
- Institute of Laboratory Medicine, University Hospital, Ludwig-Maximilians-University LMU, 81377, Munich, Germany, and
| | - Corinne Benakis
- Institute for Stroke and Dementia Research, University Hospital, Ludwig-Maximilians-University LMU, 81377, Munich, Germany
| | - Martin Giera
- Leiden University Medical Center, Center for Proteomics & Metabolomics, 2300 RC Leiden, The Netherlands
| | - Ann M Stowe
- Department of Neurology and Neurotherapeutics, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, Texas 75390
- Department of Neurology, University of Kentucky, Lexington, Kentucky 40508
| | - Arthur Liesz
- Institute for Stroke and Dementia Research, University Hospital, Ludwig-Maximilians-University LMU, 81377, Munich, Germany,
- Munich Cluster for Systems Neurology (SyNergy), 81377, Munich, Germany
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12
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Talhada D, Feiteiro J, Costa AR, Talhada T, Cairrão E, Wieloch T, Englund E, Santos CR, Gonçalves I, Ruscher K. Triiodothyronine modulates neuronal plasticity mechanisms to enhance functional outcome after stroke. Acta Neuropathol Commun 2019; 7:216. [PMID: 31864415 PMCID: PMC6925884 DOI: 10.1186/s40478-019-0866-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 12/08/2019] [Indexed: 02/07/2023] Open
Abstract
The development of new therapeutic approaches for stroke patients requires a detailed understanding of the mechanisms that enhance recovery of lost neurological functions. The efficacy to enhance homeostatic mechanisms during the first weeks after stroke will influence functional outcome. Thyroid hormones (TH) are essential regulators of neuronal plasticity, however, their role in recovery related mechanisms of neuronal plasticity after stroke remains unknown. This study addresses important findings of 3,5,3′-triiodo-L-thyronine (T3) in the regulation of homeostatic mechanisms that adjust excitability – inhibition ratio in the post-ischemic brain. This is valid during the first 2 weeks after experimental stroke induced by photothrombosis (PT) and in cultured neurons subjected to an in vitro model of acute cerebral ischemia. In the human post-stroke brain, we assessed the expression pattern of TH receptors (TR) protein levels, important for mediating T3 actions. Our results show that T3 modulates several plasticity mechanisms that may operate on different temporal and spatial scales as compensatory mechanisms to assure appropriate synaptic neurotransmission. We have shown in vivo that long-term administration of T3 after PT significantly (1) enhances lost sensorimotor function; (2) increases levels of synaptotagmin 1&2 and levels of the post-synaptic GluR2 subunit in AMPA receptors in the peri-infarct area; (3) increases dendritic spine density in the peri-infarct and contralateral region and (4) decreases tonic GABAergic signaling in the peri-infarct area by a reduced number of parvalbumin+ / c-fos+ neurons and glutamic acid decarboxylase 65/67 levels. In addition, we have shown that T3 modulates in vitro neuron membrane properties with the balance of inward glutamate ligand-gated channels currents and decreases synaptotagmin levels in conditions of deprived oxygen and glucose. Interestingly, we found increased levels of TRβ1 in the infarct core of post-mortem human stroke patients, which mediate T3 actions. Summarizing, our data identify T3 as a potential key therapeutic agent to enhance recovery of lost neurological functions after ischemic stroke.
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13
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Davidson JO, Wassink G, Draghi V, Dhillon SK, Bennet L, Gunn AJ. Limited benefit of slow rewarming after cerebral hypothermia for global cerebral ischemia in near-term fetal sheep. J Cereb Blood Flow Metab 2019; 39:2246-2257. [PMID: 30092709 PMCID: PMC6827112 DOI: 10.1177/0271678x18791631] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The optimal rate of rewarming after therapeutic hypothermia for neonatal hypoxic-ischemic encephalopathy is unknown, although it is widely suggested that slow rewarming is beneficial. Some preclinical studies suggest better outcomes with slower rewarming, but did not control for the duration of hypothermia. In this study, near-term fetal sheep (0.85 gestation) received 30 min cerebral ischemia followed by normothermia, 48 h hypothermia with rapid rewarming over 1 h, 48-h hypothermia with slow rewarming over 24 h, or 72-h hypothermia with rapid rewarming. Slow rewarming after 48 h of hypothermia improved recovery of EEG power compared with rapid rewarming (p < 0.05), but was not different from rapid rewarming after 72 h of hypothermia. At seven days recovery, neuronal survival was partially improved by both fast and slow rewarming after 48-h hypothermia, but less than 72-h hypothermia in the cortex and CA4 (p < 0.05). In conclusion, although electrographic recovery was partially improved by slow rewarming over 24 h following cerebral hypothermia for 48 h, optimal neuroprotection was seen with hypothermia for 72 h with rapid rewarming, suggesting that the overall duration of cooling was the critical determinant of outcomes after therapeutic hypothermia.
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Affiliation(s)
- Joanne O Davidson
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Guido Wassink
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Vittoria Draghi
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | | | - Laura Bennet
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Alistair J Gunn
- Department of Physiology, The University of Auckland, Auckland, New Zealand
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