1
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Voogd EJHF, Frega M, Hofmeijer J. Neuronal Responses to Ischemia: Scoping Review of Insights from Human-Derived In Vitro Models. Cell Mol Neurobiol 2023; 43:3137-3160. [PMID: 37380886 PMCID: PMC10477161 DOI: 10.1007/s10571-023-01368-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 05/27/2023] [Indexed: 06/30/2023]
Abstract
Translation of neuroprotective treatment effects from experimental animal models to patients with cerebral ischemia has been challenging. Since pathophysiological processes may vary across species, an experimental model to clarify human-specific neuronal pathomechanisms may help. We conducted a scoping review of the literature on human neuronal in vitro models that have been used to study neuronal responses to ischemia or hypoxia, the parts of the pathophysiological cascade that have been investigated in those models, and evidence on effects of interventions. We included 147 studies on four different human neuronal models. The majority of the studies (132/147) was conducted in SH-SY5Y cells, which is a cancerous cell line derived from a single neuroblastoma patient. Of these, 119/132 used undifferentiated SH-SY5Y cells, that lack many neuronal characteristics. Two studies used healthy human induced pluripotent stem cell derived neuronal networks. Most studies used microscopic measures and established hypoxia induced cell death, oxidative stress, or inflammation. Only one study investigated the effect of hypoxia on neuronal network functionality using micro-electrode arrays. Treatment targets included oxidative stress, inflammation, cell death, and neuronal network stimulation. We discuss (dis)advantages of the various model systems and propose future perspectives for research into human neuronal responses to ischemia or hypoxia.
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Affiliation(s)
- Eva J H F Voogd
- Clinical Neurophysiology, University of Twente, Enschede, The Netherlands.
| | - Monica Frega
- Clinical Neurophysiology, University of Twente, Enschede, The Netherlands
| | - Jeannette Hofmeijer
- Clinical Neurophysiology, University of Twente, Enschede, The Netherlands
- Department of Neurology, Rijnstate Hospital, Arnhem, The Netherlands
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2
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Chen B, Jin W. A comprehensive review of stroke-related signaling pathways and treatment in western medicine and traditional Chinese medicine. Front Neurosci 2023; 17:1200061. [PMID: 37351420 PMCID: PMC10282194 DOI: 10.3389/fnins.2023.1200061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 05/19/2023] [Indexed: 06/24/2023] Open
Abstract
This review provides insight into the complex network of signaling pathways and mechanisms involved in stroke pathophysiology. It summarizes the historical progress of stroke-related signaling pathways, identifying potential interactions between them and emphasizing that stroke is a complex network disease. Of particular interest are the Hippo signaling pathway and ferroptosis signaling pathway, which remain understudied areas of research, and are therefore a focus of the review. The involvement of multiple signaling pathways, including Sonic Hedgehog (SHH), nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE), hypoxia-inducible factor-1α (HIF-1α), PI3K/AKT, JAK/STAT, and AMPK in pathophysiological mechanisms such as oxidative stress and apoptosis, highlights the complexity of stroke. The review also delves into the details of traditional Chinese medicine (TCM) therapies such as Rehmanniae and Astragalus, providing an analysis of the recent status of western medicine in the treatment of stroke and the advantages and disadvantages of TCM and western medicine in stroke treatment. The review proposes that since stroke is a network disease, TCM has the potential and advantages of a multi-target and multi-pathway mechanism of action in the treatment of stroke. Therefore, it is suggested that future research should explore more treasures of TCM and develop new therapies from the perspective of stroke as a network disease.
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Affiliation(s)
- Binhao Chen
- The First School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Weifeng Jin
- College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou, China
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Fu YY, Cen JK, Song HL, Song SY, Zhang ZJ, Lu HJ. Ginsenoside Rh2 Ameliorates Neuropathic Pain by inhibition of the miRNA21-TLR8-MAPK axis. Mol Pain 2022; 18:17448069221126078. [PMID: 36039405 PMCID: PMC9478689 DOI: 10.1177/17448069221126078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Ginsenoside Rh2 is one of the major bioactive ginsenosides in Panax
ginseng. Although Rh2 is known to enhance immune cells activity for
treatment of cancer, its anti-inflammatory and neuroprotective effects have yet
to be determined. In this study, we investigated the effects of Rh2 on spared
nerve injury (SNI)-induced neuropathic pain and elucidated the potential
mechanisms. We found that various doses of Rh2 intrathecal injection
dose-dependently attenuated SNI-induced mechanical allodynia and thermal
hyperalgesia. Rh2 also inhibited microglia and astrocyte activation in the
spinal cord of a murine SNI model. Rh2 treatment inhibited SNI-induced increase
of proinflammatory cytokines, including tumor necrosis factor-α, interleukin
(IL)-1 and IL-6. Expression of miRNA-21, an endogenous ligand of Toll like
receptor (TLR)8 was also decreased. Rh2 treatment blocked the mitogen-activated
protein kinase (MAPK) signaling pathway by inhibiting of phosphorylated
extracellular signal-regulated kinase expression. Finally, intrathecal injection
of TLR8 agonist VTX-2337 reversed the analgesic effect of Rh2. These results
indicated that Rh2 relieved SNI-induced neuropathic pain via inhibiting the
miRNA-21-TLR8-MAPK signaling pathway, thus providing a potential application of
Rh2 in pain therapy.
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Affiliation(s)
- Yuan-Yuan Fu
- Institute of Pain Medicine and
Special Environmental Medicine, Nantong University, Jiangsu, China
- Department of Human Anatomy, School
of Medicine, Nantong University, Jiangsu, China
| | - Jian-Ke Cen
- Institute of Pain Medicine and
Special Environmental Medicine, Nantong University, Jiangsu, China
| | - Hao-Lin Song
- Department of Human Anatomy, School
of Medicine, Nantong University, Jiangsu, China
| | - Si-Yuan Song
- Institute of Pain Medicine and
Special Environmental Medicine, Nantong University, Jiangsu, China
| | - Zhi-Jun Zhang
- Department of Human Anatomy, School
of Medicine, Nantong University, Jiangsu, China
- Zhi-jun Zhang, Department of Human Anatomy,
School of Medicine, Nantong University, Jiangsu 226019, China,
| | - Huan-Jun Lu
- Institute of Pain Medicine and
Special Environmental Medicine, Nantong University, Jiangsu, China
- Huan-Jun Lu, Institute of Pain Medicine and
Special Environmental Medicine, Nantong University, Jiangsu 226019, China,
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4
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Bai F, Hu N, Yang R, Qu LY, Ma S, Huang J, Wang JH, Yang BF, Li CL. Tongmai granules improve rat hippocampal injury by regulating TLR4/MyD88/AP-1 signaling pathway. JOURNAL OF ETHNOPHARMACOLOGY 2022; 285:114874. [PMID: 34838942 DOI: 10.1016/j.jep.2021.114874] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/19/2021] [Accepted: 11/24/2021] [Indexed: 06/13/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Tongmai granules (TMG) is composed of Salvia miltiorrhiza Bge., Radix puerariae Lobata., and Ligusticum chuanxiong hort. TMG is mainly used for ischemic cardiovascular, cerebrovascular diseases, atherosclerosis, coronary heart disease, cerebral infarction and cerebral ischemia. TMG is a kind of traditional compound granule, which has a protective effect on brain injury. However, the potential protective mechanism of the TMG has not been elucidated. AIM OF THE STUDY TMG has a good effect on brain injury, but its brain protective mechanism is still unclear. The purpose of this study was to confirm the neuroprotective mechanism of TMG, reveal its target genes and identify the active components of TMG. MATERIALS AND METHODS High-performance liquid chromatography (HPLC) was used to identify the fingerprint of TMG. UPLC-Q-TOF-MSE was used to analyze the base peak intensity (BPI) chromatograms of TMG. TMG was pre-administered for one week, brain injury and edema were induced by injection of glutamate (Glu) into the lateral ventricles of rats. HE staining was used to investigate the pathological damage caused by Glu in the hippocampus of rats, and the RNA-seq was used to analyze the changes of different genes before and after TMG treatment. Finally, changes of related proteins were analyzed by qRT-PCR, Western blot, and other molecular biological methods. Dosage of TMG were set to 0.6 g/kg, 1.2 g/kg and 2.4 g/kg. RESULTS We found that TMG contained many active components, including salvianolic acid, puerarin, ferulic acid, etc. TMG could improve cerebral edema and brain injury induced by Glu. After TMG treatment, differential gene analysis showed that differential genes were significantly enriched in toll-like receptor signaling pathway. qRT-PCR validation results were consistent with RNA-Seq analysis results. Combined with Western blot analysis, we found that TMG ultimately regulated the expression of inflammatory cytokines by affecting the TLR4/MyD88/AP-1 pathway. CONCLUSIONS In this study, we combined TMG with RNA-seq analysis to demonstrate that TMG may play a neuroprotective role by regulating Toll-like receptor signaling pathway and down-regulating the expression of inflammatory cytokine. TMG may become a kind of traditional Chinese medicine with neuroprotective potential.
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Affiliation(s)
- Fei Bai
- Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Nan Hu
- Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Ran Yang
- Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Li-Yuan Qu
- School of Pharmacy, Harbin Medical University, Harbin, Heilongjiang, 150081, China
| | - Shuang Ma
- School of Pharmacy, Harbin Medical University, Harbin, Heilongjiang, 150081, China
| | - Jian Huang
- School of Pharmacy, Harbin Medical University, Harbin, Heilongjiang, 150081, China
| | - Jin-Hui Wang
- School of Pharmacy, Harbin Medical University, Harbin, Heilongjiang, 150081, China
| | - Bao-Feng Yang
- Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang, 110016, China; School of Pharmacy, Harbin Medical University, Harbin, Heilongjiang, 150081, China
| | - Chun-Li Li
- Department of Pharmacology, Shenyang Pharmaceutical University, Shenyang, 110016, China.
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Di Chiara T, Del Cuore A, Daidone M, Scaglione S, Norrito RL, Puleo MG, Scaglione R, Pinto A, Tuttolomondo A. Pathogenetic Mechanisms of Hypertension-Brain-Induced Complications: Focus on Molecular Mediators. Int J Mol Sci 2022; 23:ijms23052445. [PMID: 35269587 PMCID: PMC8910319 DOI: 10.3390/ijms23052445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2021] [Revised: 02/03/2022] [Accepted: 02/10/2022] [Indexed: 02/06/2023] Open
Abstract
There is growing evidence that hypertension is the most important vascular risk factor for the development and progression of cardiovascular and cerebrovascular diseases. The brain is an early target of hypertension-induced organ damage and may manifest as stroke, subclinical cerebrovascular abnormalities and cognitive decline. The pathophysiological mechanisms of these harmful effects remain to be completely clarified. Hypertension is well known to alter the structure and function of cerebral blood vessels not only through its haemodynamics effects but also for its relationships with endothelial dysfunction, oxidative stress and inflammation. In the last several years, new possible mechanisms have been suggested to recognize the molecular basis of these pathological events. Accordingly, this review summarizes the factors involved in hypertension-induced brain complications, such as haemodynamic factors, endothelial dysfunction and oxidative stress, inflammation and intervention of innate immune system, with particular regard to the role of Toll-like receptors that have to be considered dominant components of the innate immune system. The complete definition of their prognostic role in the development and progression of hypertensive brain damage will be of great help in the identification of new markers of vascular damage and the implementation of innovative targeted therapeutic strategies.
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6
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The Influence of Mitochondrial-DNA-Driven Inflammation Pathways on Macrophage Polarization: A New Perspective for Targeted Immunometabolic Therapy in Cerebral Ischemia-Reperfusion Injury. Int J Mol Sci 2021; 23:ijms23010135. [PMID: 35008558 PMCID: PMC8745401 DOI: 10.3390/ijms23010135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 12/14/2021] [Accepted: 12/19/2021] [Indexed: 12/18/2022] Open
Abstract
Cerebral ischemia-reperfusion injury is related to inflammation driven by free mitochondrial DNA. At the same time, the pro-inflammatory activation of macrophages, that is, polarization in the M1 direction, aggravates the cycle of inflammatory damage. They promote each other and eventually transform macrophages/microglia into neurotoxic macrophages by improving macrophage glycolysis, transforming arginine metabolism, and controlling fatty acid synthesis. Therefore, we propose targeting the mtDNA-driven inflammatory response while controlling the metabolic state of macrophages in brain tissue to reduce the possibility of cerebral ischemia-reperfusion injury.
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7
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Lei TY, Ye YZ, Zhu XQ, Smerin D, Gu LJ, Xiong XX, Zhang HF, Jian ZH. The immune response of T cells and therapeutic targets related to regulating the levels of T helper cells after ischaemic stroke. J Neuroinflammation 2021; 18:25. [PMID: 33461586 PMCID: PMC7814595 DOI: 10.1186/s12974-020-02057-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 12/09/2020] [Indexed: 12/21/2022] Open
Abstract
Through considerable effort in research and clinical studies, the immune system has been identified as a participant in the onset and progression of brain injury after ischaemic stroke. Due to the involvement of all types of immune cells, the roles of the immune system in stroke pathology and associated effects are complicated. Past research concentrated on the functions of monocytes and neutrophils in the pathogenesis of ischaemic stroke and tried to demonstrate the mechanisms of tissue injury and protection involving these immune cells. Within the past several years, an increasing number of studies have elucidated the vital functions of T cells in the innate and adaptive immune responses in both the acute and chronic phases of ischaemic stroke. Recently, the phenotypes of T cells with proinflammatory or anti-inflammatory function have been demonstrated in detail. T cells with distinctive phenotypes can also influence cerebral inflammation through various pathways, such as regulating the immune response, interacting with brain-resident immune cells and modulating neurogenesis and angiogenesis during different phases following stroke. In view of the limited treatment options available following stroke other than tissue plasminogen activator therapy, understanding the function of immune responses, especially T cell responses, in the post-stroke recovery period can provide a new therapeutic direction. Here, we discuss the different functions and temporal evolution of T cells with different phenotypes during the acute and chronic phases of ischaemic stroke. We suggest that modulating the balance between the proinflammatory and anti-inflammatory functions of T cells with distinct phenotypes may become a potential therapeutic approach that reduces the mortality and improves the functional outcomes and prognosis of patients suffering from ischaemic stroke.
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Affiliation(s)
- Tian-Yu Lei
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan, 430060, Hubei Province, People's Republic of China
| | - Ying-Ze Ye
- Central Laboratory, Renmin Hospital of Wuhan University, Wuhan, 430060, Hubei Province, People's Republic of China
| | - Xi-Qun Zhu
- Department of Head and Neck and Neurosurgery, Hubei Cancer Hospital, Wuhan, 430079, Hubei Province, People's Republic of China
| | - Daniel Smerin
- University of Central Florida College of Medicine, Orlando, FL, 32827, USA
| | - Li-Juan Gu
- Central Laboratory, Renmin Hospital of Wuhan University, Wuhan, 430060, Hubei Province, People's Republic of China
| | - Xiao-Xing Xiong
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan, 430060, Hubei Province, People's Republic of China.,Central Laboratory, Renmin Hospital of Wuhan University, Wuhan, 430060, Hubei Province, People's Republic of China
| | - Hong-Fei Zhang
- Department of Anesthesiology, Zhujiang Hospital of Southern Medical University, Guangzhou, Guangdong, People's Republic of China.
| | - Zhi-Hong Jian
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan, 430060, Hubei Province, People's Republic of China.
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8
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TLR8 in the Trigeminal Ganglion Contributes to the Maintenance of Trigeminal Neuropathic Pain in Mice. Neurosci Bull 2020; 37:550-562. [PMID: 33355900 PMCID: PMC8055805 DOI: 10.1007/s12264-020-00621-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 07/20/2020] [Indexed: 12/22/2022] Open
Abstract
Trigeminal neuropathic pain (TNP) is a significant health problem but the involved mechanism has not been completely elucidated. Toll-like receptors (TLRs) have recently been demonstrated to be expressed in the dorsal root ganglion and involved in chronic pain. Here, we show that TLR8 was persistently increased in the trigeminal ganglion (TG) neurons in model of TNP induced by partial infraorbital nerve ligation (pIONL). In addition, deletion or knockdown of Tlr8 in the TG attenuated pIONL-induced mechanical allodynia, reduced the activation of ERK and p38-MAPK, and decreased the expression of pro-inflammatory cytokines in the TG. Furthermore, intra-TG injection of the TLR8 agonist VTX-2337 induced pain hypersensitivity. VTX-2337 also increased the intracellular Ca2+ concentration, induced the activation of ERK and p38, and increased the expression of pro-inflammatory cytokines in the TG. These data indicate that TLR8 contributes to the maintenance of TNP through increasing MAPK-mediated neuroinflammation. Targeting TLR8 signaling may be effective for the treatment of TNP.
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9
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Li Z, Cui Y, Feng J, Guo Y. Identifying the pattern of immune related cells and genes in the peripheral blood of ischemic stroke. J Transl Med 2020; 18:296. [PMID: 32746852 PMCID: PMC7398186 DOI: 10.1186/s12967-020-02463-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 07/28/2020] [Indexed: 12/31/2022] Open
Abstract
Background Ischemic stroke (IS) is the second leading cause of death worldwide which is a serious hazard to human health. Evidence suggests that the immune system plays a key role in the pathophysiology of IS. However, the precisely immune related mechanisms were still not been systematically understood. Methods In this study, we aim to identify the immune related modules and genes that might play vital role in the occurrence and development of IS by using the weighted gene co-expression network analysis (WGCNA). Meanwhile, we applied a kind of deconvolution algorithm to reveal the proportions of 22 subsets of immune cells in the blood samples. Results There were total 128 IS patients and 67 healthy control samples in the three Gene Expression Omnibus (GEO) datasets. Under the screening criteria, 1082 DEGs (894 up-regulated and 188 down-regulated) were chosen for further analysis. A total of 11 clinically significant modules were identified, from which immune-related hub modules and hub genes were further explored. Finally, 16 genes were selected as real hub genes for further validation analysis. Furthermore, these CIBERSORT results suggest that detailed analysis of the immune subtype distribution pattern has the potential to enhance clinical prediction and to identify candidates for immunotherapy. More specifically, we identified that neutrophil emerge as a promising target for IS therapies. Conclusions In the present study, we investigated the immune related gene expression modules, in which the SLAMF1, IL7R and NCF4 may be novel therapeutic targets to promote functional and histological recovery after ischemic stroke. Furthermore, these hub genes and neutrophils may become important biological targets in the drug screening and drug designing.
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Affiliation(s)
- Zijian Li
- Department of Neurology, Shengjing Hospital of China Medical University, No. 36 Sanhao Street, Heping District, Shenyang, 110004, Liaoning, People's Republic of China
| | - Yueran Cui
- Department of Neurology, Shengjing Hospital of China Medical University, No. 36 Sanhao Street, Heping District, Shenyang, 110004, Liaoning, People's Republic of China
| | - Juan Feng
- Department of Neurology, Shengjing Hospital of China Medical University, No. 36 Sanhao Street, Heping District, Shenyang, 110004, Liaoning, People's Republic of China
| | - Yanxia Guo
- Department of Neurology, Shengjing Hospital of China Medical University, No. 36 Sanhao Street, Heping District, Shenyang, 110004, Liaoning, People's Republic of China.
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10
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Exosomes: Potential Therapies for Disease via Regulating TLRs. Mediators Inflamm 2020; 2020:2319616. [PMID: 32565722 PMCID: PMC7273472 DOI: 10.1155/2020/2319616] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 04/11/2020] [Accepted: 05/02/2020] [Indexed: 12/22/2022] Open
Abstract
Exosomes are small membrane vesicles that retain various substances such as proteins, nucleic acids, and small RNAs. Exosomes play crucial roles in many physiological and pathological processes, including innate immunity. Innate immunity is an important process that protects the organism through activating pattern recognition receptors (PRRs), which then can induce inflammatory factors to resist pathogen invasion. Toll-like receptor (TLR) is one member of PRRs and is important in pathogen clearance and nervous disease development. Although exosomes and TLRs are two independent materials, abundant evidences imply exosomes can regulate innate immunity through integrating with TLRs. Herein, we review the most recent data regarding exosome regulation of TLR pathways. Specifically, exosome-containing materials can regulate TLR pathways through the interaction with TLRs. This is a new strategy regulating immunity to resist pathogens and therapy diseases, which provide a potential method to cure diseases.
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Li M, Liu J, Bi Y, Chen J, Zhao L. Potential Medications or Compounds Acting on Toll-like Receptors in Cerebral Ischemia. Curr Neuropharmacol 2018; 16:160-175. [PMID: 28571545 PMCID: PMC5883378 DOI: 10.2174/1570159x15666170601125139] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 05/24/2017] [Accepted: 05/31/2017] [Indexed: 01/22/2023] Open
Abstract
Background: Toll-like receptors play an integral role in the process of inflammatory response after ischemic in-jury. The therapeutic potential acting on TLRs is worth of evaluations. The aim of this review was to introduce readers some potential medications or compounds which could alleviate the ischemic damage via TLRs. Methods: Research articles online on TLRs were reviewed. Categorizations were listed according to the follows, methods acting on TLRs directly, modulations of MyD88 or TRIF signaling pathway, and the ischemic tolerance induced by the pre-conditioning or postconditioning with TLR ligands or minor cerebral ischemia via acting on TLRs. Results: There are only a few studies concerning on direct effects. Anti-TLR4 or anti-TLR2 therapies may serve as promis-ing strategies in acute events. Approaches targeting on inhibiting NF-κB signaling pathway and enhancing interferon regu-latory factor dependent signaling have attracted great interests. Not only drugs but compounds extracted from traditional Chinese medicine have been used to identify their neuroprotective effects against cerebral ischemia. In addition, many re-searchers have reported the positive therapeutic effects of preconditioning with agonists of TLR2, 3, 4, 7 and 9. Several trails have also explored the potential of postconditioning, which provide a new idea in ischemic treatments. Considering all the evidence above, many drugs and new compounds may have great potential to reduce ischemic insults. Conclusion: This review will focus on promising therapies which exerting neuroprotective effects against ischemic injury by acting on TLRs.
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Affiliation(s)
- Man Li
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Jing Liu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.,Department of Neurology, Puai Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430033, China
| | - Ying Bi
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Jixiang Chen
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Lei Zhao
- Department of Infectious Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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12
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Li XB, Ding MX, Ding CL, Li LL, Feng J, Yu XJ. Toll‑Like receptor 4 promotes the phosphorylation of CRMP2 via the activation of Rho‑kinase in MCAO rats. Mol Med Rep 2018; 18:342-348. [PMID: 29749502 PMCID: PMC6059689 DOI: 10.3892/mmr.2018.8968] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 04/20/2018] [Indexed: 02/05/2023] Open
Abstract
The mechanism associated with Toll‑like receptor 4 (TLR4) in neurological injury remains unclear. The aim of the present study was to investigate the pathology of TLR4 in middle cerebral artery occlusion (MCAO)/reperfusion rat models via the regulation of collapsin response mediator protein 2 (CRMP2) phosphorylation. The modified neurological severity score (mNSS) was applied to assess neurological recovery. Immunofluorescence and western blotting were used to detect the protein expressions of TLR4, Rho‑associated protein kinase 2 (ROCK‑II) and CRMP2 following the intracerebroventricular administration of TLR4‑specific agonist, lipopolysaccharide (LPS) and TLR4‑neutralizing antibody, the ROCK‑II specific inhibitor Y‑27632 or LPS+Y‑27632 30 min prior to MCAO. The expression levels of TLR4 and the phosphorylation of CRMP2 significantly increased in response to LPS‑mediated induction and/or MCAO; however, they were reversed by treatment with LPS+TLR4‑neutralizing antibody. Y‑27632 decreased the expression of ROCK‑II and phosphorylated (p)‑CRMP2, and suppressed the increased ROCK‑II and p‑CRMP2 induced by LPS; however, no effect on the levels of TLR4 expression was observed. The neurological function as measured by mNSS score was reduced in the LPS group when compared with the MCAO group, whereas the LPS+Y‑27632 group reversed the reduced neurological function at 7 and 14 days post‑MCAO. The results of the present study suggested that TLR4 may promote the phosphorylation of CRMP2 via the activation of ROCK‑II in MCAO rats, which further characterizes the pathological mechanism of TLR4 in stroke, and that modulation of TLR4 could be a potential target to limit secondary post‑stroke brain damage.
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Affiliation(s)
- Xue-Bo Li
- Department of Forensic Medicine, Shantou University Medical College, Shantou, Guangdong 515041, P.R. China
- Key Laboratory of Evidence Identification in Universities of Shandong, Shandong University of Political Science and Law, Jinan, Shandong 250014, P.R. China
| | - Ming-Xia Ding
- Department of Obstetrics and Gynecology, The Second Hospital of Shandong University, Jinan, Shandong 250014, P.R. China
| | - Chun-Li Ding
- Key Laboratory of Evidence Identification in Universities of Shandong, Shandong University of Political Science and Law, Jinan, Shandong 250014, P.R. China
| | - Liang-Liang Li
- Key Laboratory of Evidence Identification in Universities of Shandong, Shandong University of Political Science and Law, Jinan, Shandong 250014, P.R. China
| | - Jinzhou Feng
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China
| | - Xiao-Jun Yu
- Department of Forensic Medicine, Shantou University Medical College, Shantou, Guangdong 515041, P.R. China
- Correspondence to: Dr Xiao-Jun Yu, Department of Forensic Medicine, Shantou University Medical College, 22 Xinling Road, Shantou, Guangdong 515041, P.R. China, E-mail:
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13
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Notch signaling and neuronal death in stroke. Prog Neurobiol 2018; 165-167:103-116. [PMID: 29574014 DOI: 10.1016/j.pneurobio.2018.03.002] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 02/08/2018] [Accepted: 03/20/2018] [Indexed: 12/18/2022]
Abstract
Ischemic stroke is a leading cause of morbidity and death, with the outcome largely determined by the amount of hypoxia-related neuronal death in the affected brain regions. Cerebral ischemia and hypoxia activate the Notch1 signaling pathway and four prominent interacting pathways (NF-κB, p53, HIF-1α and Pin1) that converge on a conserved DNA-associated nuclear multi-protein complex, which controls the expression of genes that can determine the fate of neurons. When neurons experience a moderate level of ischemic insult, the nuclear multi-protein complex up-regulates adaptive stress response genes encoding proteins that promote neuronal survival, but when ischemia is more severe the nuclear multi-protein complex induces genes encoding proteins that trigger and execute a neuronal death program. We propose that the nuclear multi-protein transcriptional complex is a molecular mediator of neuronal hormesis and a target for therapeutic intervention in stroke.
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Anttila JE, Whitaker KW, Wires ES, Harvey BK, Airavaara M. Role of microglia in ischemic focal stroke and recovery: focus on Toll-like receptors. Prog Neuropsychopharmacol Biol Psychiatry 2017; 79:3-14. [PMID: 27389423 PMCID: PMC5214845 DOI: 10.1016/j.pnpbp.2016.07.003] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 06/20/2016] [Accepted: 07/02/2016] [Indexed: 12/21/2022]
Abstract
Stroke is the leading cause of disability in adults. Drug treatments that target stroke-induced pathological mechanisms and promote recovery are desperately needed. In the brain, an ischemic event triggers major inflammatory responses that are mediated by the resident microglial cells. In this review, we focus on the microglia activation after ischemic brain injury as a target of immunomodulatory therapeutics. We divide the microglia-mediated events following ischemic stroke into three categories: acute, subacute, and long-term events. This division encompasses the spatial and temporal dynamics of microglia as they participate in the pathophysiological changes that contribute to the symptoms and sequela of a stroke. The importance of Toll-like receptor (TLR) signaling in the outcomes of these pathophysiological changes is highlighted. Increasing evidence shows that microglia have a complex role in stroke pathophysiology, and they mediate both detrimental and beneficial effects on stroke outcome. So far, most of the pharmacological studies in experimental models of stroke have focused on neuroprotective strategies which are impractical for clinical applications. Post-ischemic inflammation is long lasting and thus, could provide a therapeutic target for novel delayed drug treatment. However, more studies are needed to elucidate the role of microglia in the recovery process from an ischemic stroke and to evaluate the therapeutic potential of modulating post-ischemic inflammation to promote functional recovery.
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Affiliation(s)
- Jenni E Anttila
- Institute of Biotechnology, P.O. Box 56, 00014, University of Helsinki, Finland
| | - Keith W Whitaker
- Intramural Research Program, National Institute on Drug Abuse, NIH, Baltimore, MD, USA; Human Research and Engineering Directorate, US Army Research Laboratory, Aberdeen, Proving Ground, MD 21005, USA
| | - Emily S Wires
- Intramural Research Program, National Institute on Drug Abuse, NIH, Baltimore, MD, USA
| | - Brandon K Harvey
- Intramural Research Program, National Institute on Drug Abuse, NIH, Baltimore, MD, USA
| | - Mikko Airavaara
- Institute of Biotechnology, P.O. Box 56, 00014, University of Helsinki, Finland.
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Thom V, Arumugam TV, Magnus T, Gelderblom M. Therapeutic Potential of Intravenous Immunoglobulin in Acute Brain Injury. Front Immunol 2017; 8:875. [PMID: 28824617 PMCID: PMC5534474 DOI: 10.3389/fimmu.2017.00875] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 07/10/2017] [Indexed: 12/31/2022] Open
Abstract
Acute ischemic and traumatic injury of the central nervous system (CNS) is known to induce a cascade of inflammatory events that lead to secondary tissue damage. In particular, the sterile inflammatory response in stroke has been intensively investigated in the last decade, and numerous experimental studies demonstrated the neuroprotective potential of a targeted modulation of the immune system. Among the investigated immunomodulatory agents, intravenous immunoglobulin (IVIg) stand out due to their beneficial therapeutic potential in experimental stroke as well as several other experimental models of acute brain injuries, which are characterized by a rapidly evolving sterile inflammatory response, e.g., trauma, subarachnoid hemorrhage. IVIg are therapeutic preparations of polyclonal immunoglobulin G, extracted from the plasma of thousands of donors. In clinical practice, IVIg are the treatment of choice for diverse autoimmune diseases and various mechanisms of action have been proposed. Only recently, several experimental studies implicated a therapeutic potential of IVIg even in models of acute CNS injury, and suggested that the immune system as well as neuronal cells can directly be targeted by IVIg. This review gives further insight into the role of secondary inflammation in acute brain injury with an emphasis on stroke and investigates the therapeutic potential of IVIg.
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Affiliation(s)
- Vivien Thom
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Thiruma V Arumugam
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Tim Magnus
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Mathias Gelderblom
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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Ng GJ, Quek AM, Cheung C, Arumugam TV, Seet RC. Stroke biomarkers in clinical practice: A critical appraisal. Neurochem Int 2017; 107:11-22. [DOI: 10.1016/j.neuint.2017.01.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 01/05/2017] [Accepted: 01/08/2017] [Indexed: 02/04/2023]
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Wang KC, Tang SC, Lee JE, Li YI, Huang YS, Yang WS, Jeng JS, Arumugam TV, Tu YK. Cerebrospinal fluid high mobility group box 1 is associated with neuronal death in subarachnoid hemorrhage. J Cereb Blood Flow Metab 2017; 37:435-443. [PMID: 26823474 PMCID: PMC5381442 DOI: 10.1177/0271678x16629484] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We aim to determine the cerebrospinal fluid levels of high mobility group box 1 in subarachnoid hemorrhage patients and to investigate the involvement of the receptor for advanced glycation end products and high mobility group box 1 in the pathogenesis of post-subarachnoid hemorrhage neuronal death. The study included 40 patients (mean age, 59 ± 19 years) with Fisher's grade ≥ III aneurysmal subarachnoid hemorrhage. Cerebrospinal fluid was collected on the seventh day post-hemorrhage. Receptor for advanced glycation end products expression was examined in rat brain tissue following subarachnoid hemorrhage and in cultured neurons exposed to post-subarachnoid hemorrhage cerebrospinal fluid. Therapeutic effects of the recombinant soluble form of RAGE on subarachnoid hemorrhage models were also investigated. The results indicated that a higher level of cerebrospinal fluid high mobility group box 1 was independently associated with unfavorable outcome at three months post-subarachnoid hemorrhage (OR = 1.061, 95% CI: 1.005-1.121). Expression of RAGE increased in post-subarachnoid hemorrhage rat brain cells and in cultured neuron with stimulation of post-subarachnoid hemorrhage cerebrospinal fluid. Administration of recombinant soluble form of RAGE significantly reduced the number of positive TUNEL staining cells in subarachnoid hemorrhage rat and improved cell viability in post-subarachnoid hemorrhage cerebrospinal fluid-treated cultured neurons. Thus, the level of cerebrospinal fluid high mobility group box 1 can be a prognostic indicator for patients with Fisher's grade ≥ III aneurysmal subarachnoid hemorrhage and that treatment with soluble form of RAGE is a novel approach for subarachnoid hemorrhage.
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Affiliation(s)
- Kuo-Chuan Wang
- 1 Division of Neurosurgery, Department of Surgery, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
| | - Sung-Chun Tang
- 2 Department of Neurology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
| | - Jing-Er Lee
- 3 Department of Neurology, Taipei Medical University-Wan Fang Hospital, Taipei, Taiwan
| | - Yu-I Li
- 4 Department and Graduate Institute of Forensic Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Yi-Shuian Huang
- 5 Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Wei-Shiung Yang
- 6 Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.,7 Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University Taipei, Taiwan
| | - Jiann-Shing Jeng
- 2 Department of Neurology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
| | - Thiruma V Arumugam
- 8 Department of Physiology, Yong Loo Lin School Medicine, National University of Singapore, Singapore
| | - Yong-Kwang Tu
- 1 Division of Neurosurgery, Department of Surgery, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
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Gu L, Zhou J, Tan J, Yang J, Shen T, Jiang H, Tang Q. Association of TLR8 gene rs3764880 polymorphisms with susceptibility and lipid metabolism- and inflammation response-related quantitative traits of ischemic stroke in southern Chinese Han male population. J Neurol Sci 2016; 370:94-99. [DOI: 10.1016/j.jns.2016.08.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 07/21/2016] [Accepted: 08/09/2016] [Indexed: 10/21/2022]
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Goulopoulou S, McCarthy CG, Webb RC. Toll-like Receptors in the Vascular System: Sensing the Dangers Within. Pharmacol Rev 2016; 68:142-67. [PMID: 26721702 DOI: 10.1124/pr.114.010090] [Citation(s) in RCA: 170] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Toll-like receptors (TLRs) are components of the innate immune system that respond to exogenous infectious ligands (pathogen-associated molecular patterns, PAMPs) and endogenous molecules that are released during host tissue injury/death (damage-associated molecular patterns, DAMPs). Interaction of TLRs with their ligands leads to activation of downstream signaling pathways that induce an immune response by producing inflammatory cytokines, type I interferons (IFN), and other inflammatory mediators. TLR activation affects vascular function and remodeling, and these molecular events prime antigen-specific adaptive immune responses. Despite the presence of TLRs in vascular cells, the exact mechanisms whereby TLR signaling affects the function of vascular tissues are largely unknown. Cardiovascular diseases are considered chronic inflammatory conditions, and accumulating data show that TLRs and the innate immune system play a determinant role in the initiation and development of cardiovascular diseases. This evidence unfolds a possibility that targeting TLRs and the innate immune system may be a novel therapeutic goal for these conditions. TLR inhibitors and agonists are already in clinical trials for inflammatory conditions such as asthma, cancer, and autoimmune diseases, but their study in the context of cardiovascular diseases is in its infancy. In this article, we review the current knowledge of TLR signaling in the cardiovascular system with an emphasis on atherosclerosis, hypertension, and cerebrovascular injury. Furthermore, we address the therapeutic potential of TLR as pharmacological targets in cardiovascular disease and consider intriguing research questions for future study.
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Affiliation(s)
- Styliani Goulopoulou
- Institute for Cardiovascular and Metabolic Diseases, Department of Obstetrics and Gynecology, University of North Texas Health Science Center, Fort Worth, Texas; and Department of Physiology, Augusta University, Augusta, Georgia
| | - Cameron G McCarthy
- Institute for Cardiovascular and Metabolic Diseases, Department of Obstetrics and Gynecology, University of North Texas Health Science Center, Fort Worth, Texas; and Department of Physiology, Augusta University, Augusta, Georgia
| | - R Clinton Webb
- Institute for Cardiovascular and Metabolic Diseases, Department of Obstetrics and Gynecology, University of North Texas Health Science Center, Fort Worth, Texas; and Department of Physiology, Augusta University, Augusta, Georgia
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Gu L, Zhou J, Tan J, Su L, Wei Q, Jiang H, Liang B, Tang Q. TLR7 rs2897827 Polymorphism Affects TLR7 Gene mRNA Expression and Serum Apolipoprotein A1 Level of Ischemic Stroke Patients in a Chinese Han Population. J Mol Neurosci 2016; 59:397-403. [PMID: 27427388 DOI: 10.1007/s12031-016-0773-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 05/25/2016] [Indexed: 01/27/2023]
Abstract
Stroke is a multi-factorial disorder that has become the leading cause of death and disability worldwide. Previous studies reported that TLR7 mRNA expression is associated with poor outcome of ischemic stroke (IS). This study aimed to assess whether TLR7 mRNA expression affects IS occurrence, as well as the association of TLR7 rs2897827 with susceptibility to IS and TLR7 mRNA expression and serum apolipoprotein and lipid levels in a Chinese Han population. A total of 816 stroke patients and 816 healthy controls were included in this study. mRNA expression was determined by quantitative real-time PCR. The Sequenom MassARRAY iPLEX platform was used to genotype the TLR7 rs2897827 polymorphism. TLR7 mRNA expression of the IS cases was statistically significantly higher than that of the controls in the male or female group (male, P = 0.014; female, P = 0.025). In the male IS cases, TLR7 mRNA expression of the T allele carriers was statistically significantly higher than that of the C allele carriers (P = 0.018). However, a significant difference was not observed in the female cases (P = 0.545). In either the male or female group, the distribution of genotype or allele had no statistical significance (P > 0.050). The ApoA1 level of the T carriers was statistically significantly higher than the C carriers in males (t = -2.383, P = 0.020); however, the ApoB and lipid levels were not associated with rs2897827 (P > 0.050). In female patients, no significant difference was observed between different genotypic/allelic carriers in serum apolipoprotein and lipid levels (all P > 0.050). The expression of the TLR7 gene may affect IS occurrence. TLR7 gene rs2897827 may influence TLR7 mRNA expression and the plasma ApoA1 level in male IS patients.
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Affiliation(s)
- Lian Gu
- First Affiliated Hospital, Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Jinying Zhou
- First Affiliated Hospital, Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Jinjing Tan
- First Affiliated Hospital, Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Li Su
- School of Public Health, Guangxi Medical University, Nanning, Guangxi, China
| | - Qiugui Wei
- First Affiliated Hospital, Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Haiyun Jiang
- First Affiliated Hospital, Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Baoyun Liang
- First Affiliated Hospital, Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Qianli Tang
- You Jiang Medical University for Nationalities, 98 Chengxiang Road, Baise, Guangxi, 533000, China.
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Wang PF, Xiong XY, Chen J, Wang YC, Duan W, Yang QW. Function and mechanism of toll-like receptors in cerebral ischemic tolerance: from preconditioning to treatment. J Neuroinflammation 2015; 12:80. [PMID: 25928750 PMCID: PMC4422156 DOI: 10.1186/s12974-015-0301-0] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 04/13/2015] [Indexed: 01/13/2023] Open
Abstract
Increasing evidence suggests that toll-like receptors (TLRs) play an important role in cerebral ischemia-reperfusion injury. The endogenous ligands released from ischemic neurons activate the TLR signaling pathway, resulting in the production of a large number of inflammatory cytokines, thereby causing secondary inflammation damage following cerebral ischemia. However, the preconditioning for minor cerebral ischemia or the preconditioning with TLR ligands can reduce cerebral ischemic injury by regulating the TLR signaling pathway following ischemia in brain tissue (mainly, the inhibition of the TLR4/NF-κB signaling pathway and the enhancement of the interferon regulatory factor-dependent signaling), resulting in TLR ischemic tolerance. Additionally, recent studies found that postconditioning with TLR ligands after cerebral ischemia can also reduce ischemic damage through the regulation of the TLR signaling pathway, showing a significant therapeutic effect against cerebral ischemia. These studies suggest that the ischemic tolerance mediated by TLRs can serve as an important target for the prevention and treatment of cerebral ischemia. On the basis of describing the function and mechanism of TLRs in mediating cerebral ischemic damage, this review focuses on the mechanisms of cerebral ischemic tolerance induced by the preconditioning and postconditioning of TLRs and discusses the clinical application of TLRs for ischemic tolerance.
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Affiliation(s)
- Peng-Fei Wang
- Department of Neurology, Xinqiao Hospital & the Second Affiliated Hospital, the Third Military Medical University, No. 183, Xinqiao Main Street, Shapingba District, Chongqing, 400037, China. .,Department of Neurology, Weihai municipal Hospital, Weihai, 264200, China.
| | - Xiao-Yi Xiong
- Department of Neurology, Xinqiao Hospital & the Second Affiliated Hospital, the Third Military Medical University, No. 183, Xinqiao Main Street, Shapingba District, Chongqing, 400037, China.
| | - Jing Chen
- Department of Neurology, Xinqiao Hospital & the Second Affiliated Hospital, the Third Military Medical University, No. 183, Xinqiao Main Street, Shapingba District, Chongqing, 400037, China.
| | - Yan-Chun Wang
- Department of Neurology, Xinqiao Hospital & the Second Affiliated Hospital, the Third Military Medical University, No. 183, Xinqiao Main Street, Shapingba District, Chongqing, 400037, China.
| | - Wei Duan
- Department of Neurology, Xinqiao Hospital & the Second Affiliated Hospital, the Third Military Medical University, No. 183, Xinqiao Main Street, Shapingba District, Chongqing, 400037, China.
| | - Qing-Wu Yang
- Department of Neurology, Xinqiao Hospital & the Second Affiliated Hospital, the Third Military Medical University, No. 183, Xinqiao Main Street, Shapingba District, Chongqing, 400037, China.
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Intravenous immunoglobulin (IVIg) dampens neuronal toll-like receptor-mediated responses in ischemia. J Neuroinflammation 2015; 12:73. [PMID: 25886362 PMCID: PMC4409750 DOI: 10.1186/s12974-015-0294-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 04/02/2015] [Indexed: 11/14/2022] Open
Abstract
Background Ischemic stroke causes a high rate of deaths and permanent neurological damage in survivors. Ischemic stroke triggers the release of damage-associated molecular patterns (DAMPs) such as high-mobility group box 1 (HMGB1), which activate toll-like receptors (TLRs) and receptor for advanced glycation endproducts (RAGE) in the affected area, leading to an exaggerated inflammatory response and cell death. Both TLRs and RAGE are transmembrane pattern recognition receptors (PRRs) that have been shown to contribute to ischemic stroke-induced brain injury. Intravenous immunoglobulin (IVIg) preparations obtained by fractionating human blood plasma are increasingly being used as an effective therapeutic agent in the treatment of several inflammatory diseases. Its use as a potential therapeutic agent for treatment of stroke has been proposed, but little is known about the direct neuroprotective mechanisms of IVIg. We therefore investigate whether IVIg exerts its beneficial effects on the outcome of neuronal injury by modulating HMGB1-induced TLR and RAGE expressions and activations. Methods Primary cortical neurons were subjected to glucose deprivation or oxygen and glucose deprivation conditions and treated with IVIg and recombinant HMGB1. C57/BL6J mice were subjected to middle cerebral artery occlusion, followed by reperfusion, and IVIg was administered intravenously 3 h after the start of reperfusion. Expression of TLRs, RAGE and downstream signalling proteins in neurons and brain tissues were evaluated by immunoblot. Results Treatment of cultured neurons with IVIg reduced simulated ischemia-induced TLR2, TLR4, TLR8 and RAGE expressions, pro-apoptotic caspase-3 cleavage and phosphorylation of the cell death-associated kinases such as c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (MAPK) as well as the p65 subunit of nuclear factor kappa B (NF-κB). These results were recapitulated in an in vivo model of stroke. IVIg treatment also upregulated the anti-apoptotic protein B-cell lymphoma 2 (Bcl-2) in cortical neurons under ischemic conditions. Finally, IVIg protected neurons against HMGB1-induced neuronal cell death by modulating TLR and RAGE expressions and signalling pathways. Conclusions Taken together, these results provide a rationale for the potential use of IVIg to target inappropriately activated components of the innate immune system following ischemic stroke.
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Role of toll-like receptors in multiple myeloma and recent advances. Exp Hematol 2014; 43:158-67. [PMID: 25462020 DOI: 10.1016/j.exphem.2014.11.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 11/02/2014] [Accepted: 11/10/2014] [Indexed: 12/22/2022]
Abstract
Multiple myeloma (MM) is a hematologic malignancy characterized as an abnormal proliferation and invasion of plasma cells into the bone marrow. Toll-like receptors (ТLRs) connect the innate and adaptive immune responses and represent a significant and potentially linking element between inflammation and cancer. When TLRs bind to their ligands, they trigger two major signaling pathways such that both share overlapping downstream signals: one is a myeloid differentiation primary response 88 (MyD88)-dependent production and activation of nuclear factor-κB, whereas the other is a MyD88-independent production of type-I interferon. Whereas the MyD88 pathway results in proinflammatory cytokine production, the other pathway stimulates cell proliferation. Dysregulations of these pathways may eventually lead to abnormal cell proliferation and MM. Despite recent biomedical advances, MM continues to be an incurable disease. There are an increasing number of TLR-based therapeutic approaches currently being tested in a number of preclinical and clinical studies. We here attempt to outline in detail the currently available information on TLRs in various types of cancer.
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Tang SC, Yeh SJ, Tsai LK, Hu CJ, Lien LM, Peng GS, Yang WS, Chiou HY, Jeng JS. Association between plasma levels of hyaluronic acid and functional outcome in acute stroke patients. J Neuroinflammation 2014; 11:101. [PMID: 24912490 PMCID: PMC4066288 DOI: 10.1186/1742-2094-11-101] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2014] [Accepted: 05/28/2014] [Indexed: 12/12/2022] Open
Abstract
Background Activation of hyaluronic acid (HA) and associated enzyme synthesis has been demonstrated in experimental stroke animal models. Our study aimed to investigate the plasma levels of HA in acute stroke patients and the associations between HA levels and functional outcome. Methods This was a multicenter case–control study. Acute stroke patients and age- and sex-matched non-stroke controls were recruited. Plasma levels of HA in acute stroke patients were determined at <48 hours and at 48 to 72 hours after stroke onset by standard ELISA. Favorable functional outcome was defined as modified Rankin scale ≤2 at 3 months after stroke. Results The study included 206 acute stroke patients, including 43 who had intracerebral hemorrhage and 163 who had ischemic stroke, and 159 controls. The plasma levels of HA in the acute stroke patients were significantly higher than those in the controls (219.7 ± 203.4 ng/ml for <48 hours and 343.1 ± 710.3 ng/ml for 48 to 72 hours versus 170.4 ± 127.9 ng/ml in the controls; both P < 0.05). For intracerebral hemorrhage patients, HA ≤500 ng/ml (<48 hours) was an independent favorable outcome predictor (P = 0.016). For ischemic stroke patients, an inverted U-shaped association between plasma HA (48 to 72 hours) and outcome was noted, indicating that ischemic stroke patients with too high or too low plasma HA levels tended to have an unfavorable outcome. Conclusion HA plasma level was elevated in patients with acute stroke, and can predict 3-month functional outcome, particularly for patients with intracerebral hemorrhage.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Jiann-Shing Jeng
- Stroke Center and Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan.
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The Yin and Yang of innate immunity in stroke. BIOMED RESEARCH INTERNATIONAL 2014; 2014:807978. [PMID: 24877133 PMCID: PMC4021995 DOI: 10.1155/2014/807978] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 04/15/2014] [Indexed: 11/18/2022]
Abstract
Immune system plays an elementary role in the pathophysiological progress of ischemic stroke. It consists of innate and adaptive immune system. Activated within minutes after ischemic onset, innate immunity is responsible for the elimination of necrotic cells and tissue repair, while it is critically involved in the initiation and amplification of poststroke inflammation that amplifies ischemic damage to the brain tissue. Innate immune response requires days to be fully developed, providing a considerable time window for therapeutic intervention, suggesting prospect of novel immunomodulatory therapies against poststroke inflammation-induced brain injury. However, obstacles still exist and a comprehensive understanding of ischemic stroke and innate immune reaction is essential. In this review, we highlighted the current experimental and clinical data depicting the innate immune response following ischemic stroke, mainly focusing on the recognition of damage-associated molecular patterns, activation and recruitment of innate immune cells, and involvement of various cytokines. In addition, clinical trials targeting innate immunity were also documented regardless of the outcome, stressing the requirements for further investigation.
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Minter MR, Zhang M, Ates RC, Taylor JM, Crack PJ. Type-1 interferons contribute to oxygen glucose deprivation induced neuro-inflammation in BE(2)M17 human neuroblastoma cells. J Neuroinflammation 2014; 11:43. [PMID: 24602263 PMCID: PMC3995960 DOI: 10.1186/1742-2094-11-43] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Accepted: 02/21/2014] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Hypoxic-ischaemic injuries such as stroke and traumatic brain injury exhibit features of a distinct neuro-inflammatory response in the hours and days post-injury. Microglial activation, elevated pro-inflammatory cytokines and macrophage infiltration contribute to core tissue damage and contribute to secondary injury within a region termed the penumbra. Type-1 interferons (IFNs) are a super-family of pleiotropic cytokines that regulate pro-inflammatory gene transcription via the classical Jak/Stat pathway; however their role in hypoxia-ischaemia and central nervous system neuro-inflammation remains unknown. Using an in vitro approach, this study investigated the role of type-1 IFN signalling in an inflammatory setting induced by oxygen glucose deprivation (OGD). METHODS Human BE(2)M17 neuroblastoma cells or cells expressing a type-1 interferon-α receptor 1 (IFNAR1) shRNA or negative control shRNA knockdown construct were subjected to 4.5 h OGD and a time-course reperfusion period (0 to 24 h). Q-PCR was used to evaluate IFNα, IFNβ, IL-1β, IL-6 and TNF-α cytokine expression levels. Phosphorylation of signal transducers and activators of transcription (STAT)-1, STAT-3 and cleavage of caspase-3 was detected by western blot analysis. Post-OGD cellular viability was measured using a MTT assay. RESULTS Elevated IFNα and IFNβ expression was detected during reperfusion post-OGD in parental M17 cells. This correlated with enhanced phosphorylation of STAT-1, a downstream type-1 IFN signalling mediator. Significantly, ablation of type-1 IFN signalling, through IFNAR1 knockdown, reduced IFNα, IFNβ, IL-6 and TNF-α expression in response to OGD. In addition, MTT assay confirmed the IFNAR1 knockdown cells were protected against OGD compared to negative control cells with reduced pro-apoptotic cleaved caspase-3 levels. CONCLUSIONS This study confirms a role for type-1 IFN signalling in the neuro-inflammatory response following OGD in vitro and suggests its modulation through therapeutic blockade of IFNAR1 may be beneficial in reducing hypoxia-induced neuro-inflammation.
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Affiliation(s)
| | | | | | | | - Peter John Crack
- Department of Pharmacology, University of Melbourne, 8th floor, Medical building, Grattan St, Parkville 3010, VIC, Australia.
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A heavy toll on the outcome of ischemic brain stroke. Exp Neurol 2014; 254:166-7. [PMID: 24512751 DOI: 10.1016/j.expneurol.2014.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 01/20/2014] [Accepted: 02/02/2014] [Indexed: 11/24/2022]
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