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Martín-Loro F, Cano-Cano F, Ortega MJ, Cuevas B, Gómez-Jaramillo L, González-Montelongo MDC, Freisenhausen JC, Lara-Barea A, Campos-Caro A, Zubía E, Aguilar-Diosdado M, Arroba AI. Arylphthalide Delays Diabetic Retinopathy via Immunomodulating the Early Inflammatory Response in an Animal Model of Type 1 Diabetes Mellitus. Int J Mol Sci 2024; 25:8440. [PMID: 39126007 PMCID: PMC11313200 DOI: 10.3390/ijms25158440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2024] [Revised: 07/30/2024] [Accepted: 07/30/2024] [Indexed: 08/12/2024] Open
Abstract
Diabetic retinopathy (DR) is one of the most prevalent secondary complications associated with diabetes. Specifically, Type 1 Diabetes Mellitus (T1D) has an immune component that may determine the evolution of DR by compromising the immune response of the retina, which is mediated by microglia. In the early stages of DR, the permeabilization of the blood-retinal barrier allows immune cells from the peripheral system to interact with the retinal immune system. The use of new bioactive molecules, such as 3-(2,4-dihydroxyphenyl)phthalide (M9), with powerful anti-inflammatory activity, might represent an advance in the treatment of diseases like DR by targeting the immune systems responsible for its onset and progression. Our research aimed to investigate the molecular mechanisms involved in the interaction of specific cells of the innate immune system during the progression of DR and the reduction in inflammatory processes contributing to the pathology. In vitro studies were conducted exposing Bv.2 microglial and Raw264.7 macrophage cells to proinflammatory stimuli for 24 h, in the presence or absence of M9. Ex vivo and in vivo approaches were performed in BB rats, an animal model for T1D. Retinal explants from BB rats were cultured with M9. Retinas from BB rats treated for 15 days with M9 via intraperitoneal injection were analyzed to determine survival, cellular signaling, and inflammatory markers using qPCR, Western blot, or immunofluorescence approaches. Retinal structure images were acquired via Spectral-Domain-Optical Coherence Tomography (SD-OCT). Our results show that the treatment with M9 significantly reduces inflammatory processes in in vitro, ex vivo, and in vivo models of DR. M9 works by inhibiting the proinflammatory responses during DR progression mainly affecting immune cell responses. It also induces an anti-inflammatory response, primarily mediated by microglial cells, leading to the synthesis of Arginase-1 and Hemeoxygenase-1(HO-1). Ultimately, in vivo administration of M9 preserves the retinal integrity from the degeneration associated with DR progression. Our findings demonstrate a specific interaction between both retinal and systemic immune cells in the progression of DR, with a differential response to treatment, mainly driven by microglia in the anti-inflammatory action. In vivo treatment with M9 induces a switch in immune cell phenotypes and functions that contributes to delaying the DR progression, positioning microglial cells as a new and specific therapeutic target in DR.
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Affiliation(s)
- Francisco Martín-Loro
- Diabetes Mellitus Laboratory, Instituto de Investigación e Innovación en Ciencias Biomédicas de la Provincia de Cádiz (INiBICA), Hospital Universitario Puerta del Mar, 11009 Cádiz, Spain; (F.M.-L.); (F.C.-C.); (B.C.); (L.G.-J.); (M.d.C.G.-M.); (M.A.-D.)
| | - Fátima Cano-Cano
- Diabetes Mellitus Laboratory, Instituto de Investigación e Innovación en Ciencias Biomédicas de la Provincia de Cádiz (INiBICA), Hospital Universitario Puerta del Mar, 11009 Cádiz, Spain; (F.M.-L.); (F.C.-C.); (B.C.); (L.G.-J.); (M.d.C.G.-M.); (M.A.-D.)
| | - María J. Ortega
- Departamento de Química Orgánica, Facultad de Ciencias del Mar y Ambientales, Universidad de Cádiz, 11510 Puerto Real, Spain; (M.J.O.); (E.Z.)
| | - Belén Cuevas
- Diabetes Mellitus Laboratory, Instituto de Investigación e Innovación en Ciencias Biomédicas de la Provincia de Cádiz (INiBICA), Hospital Universitario Puerta del Mar, 11009 Cádiz, Spain; (F.M.-L.); (F.C.-C.); (B.C.); (L.G.-J.); (M.d.C.G.-M.); (M.A.-D.)
- Departamento de Química Orgánica, Facultad de Ciencias del Mar y Ambientales, Universidad de Cádiz, 11510 Puerto Real, Spain; (M.J.O.); (E.Z.)
| | - Laura Gómez-Jaramillo
- Diabetes Mellitus Laboratory, Instituto de Investigación e Innovación en Ciencias Biomédicas de la Provincia de Cádiz (INiBICA), Hospital Universitario Puerta del Mar, 11009 Cádiz, Spain; (F.M.-L.); (F.C.-C.); (B.C.); (L.G.-J.); (M.d.C.G.-M.); (M.A.-D.)
| | - María del Carmen González-Montelongo
- Diabetes Mellitus Laboratory, Instituto de Investigación e Innovación en Ciencias Biomédicas de la Provincia de Cádiz (INiBICA), Hospital Universitario Puerta del Mar, 11009 Cádiz, Spain; (F.M.-L.); (F.C.-C.); (B.C.); (L.G.-J.); (M.d.C.G.-M.); (M.A.-D.)
| | - Jan Cedric Freisenhausen
- Dermatology and Venereology Division, Department of Medicine, Karolinska Institute, SE-171 77 Solna, Sweden;
- Center for Molecular Medicine, Karolinska University Hospital, SE-171 76 Solna, Sweden
| | - Almudena Lara-Barea
- Department of Endocrinology and Metabolism, University Hospital Puerta del Mar, 11009 Cádiz, Spain;
| | - Antonio Campos-Caro
- Área Genética, Departamento Biomedicina Biotecnología y Salud Pública, Universidad de Cádiz, 11510 Puerto Real, Spain;
| | - Eva Zubía
- Departamento de Química Orgánica, Facultad de Ciencias del Mar y Ambientales, Universidad de Cádiz, 11510 Puerto Real, Spain; (M.J.O.); (E.Z.)
| | - Manuel Aguilar-Diosdado
- Diabetes Mellitus Laboratory, Instituto de Investigación e Innovación en Ciencias Biomédicas de la Provincia de Cádiz (INiBICA), Hospital Universitario Puerta del Mar, 11009 Cádiz, Spain; (F.M.-L.); (F.C.-C.); (B.C.); (L.G.-J.); (M.d.C.G.-M.); (M.A.-D.)
- Department of Endocrinology and Metabolism, University Hospital Puerta del Mar, 11009 Cádiz, Spain;
| | - Ana I. Arroba
- Diabetes Mellitus Laboratory, Instituto de Investigación e Innovación en Ciencias Biomédicas de la Provincia de Cádiz (INiBICA), Hospital Universitario Puerta del Mar, 11009 Cádiz, Spain; (F.M.-L.); (F.C.-C.); (B.C.); (L.G.-J.); (M.d.C.G.-M.); (M.A.-D.)
- Department of Endocrinology and Metabolism, University Hospital Puerta del Mar, 11009 Cádiz, Spain;
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Wang K, Yang L, Li Q, Yang X, Chen Z, Zhou Y, Jia Y, Gong Z. Long-Term Alcohol Exposure Aggravates Ischemic Stroke-Induced Damage by Promoting Pericyte NLRP3 Inflammasome Activation via Pre-Activating the TLR4/NF-κB Pathway in Rats. J Inflamm Res 2024; 17:4791-4810. [PMID: 39051052 PMCID: PMC11268848 DOI: 10.2147/jir.s465780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Accepted: 06/25/2024] [Indexed: 07/27/2024] Open
Abstract
Background Ischemic stroke (IS) is one of the leading causes of death and disability in the world, and alcohol consumption has been gaining attention as an independent risk factor for IS. Blood-brain barrier (BBB) dysfunction and neuroinflammation are the core of cerebral ischemia/reperfusion (I/R) injury, and pericytes play a crucial role in the structure and function. This study is to explore the effects of long-term alcohol consumption on IS and the potential mechanisms of pericytes. Methods Rat models of long-term alcohol intake followed by transient middle cerebral artery occlusion stroke (EtOH+tMCAO) and cell models of oxygen-glucose deprivation/reoxygenation (OGD/R) with alcohol pre-treatment were constructed. Results Worsened infarct volume, neurological scores, and BBB disruption were observed in the EtOH+tMCAO group compared with the tMCAO group, and immunofluorescence staining showed increased pericytes NLPR3 inflammasome activation at the ischemic penumbra. In vitro, pericyte mortality and LDH release elevated pre-treated by alcohol after OGD/R, and amplified expression of NLRP3 inflammasome was detected by Western blotting and qPCR. Alcohol pre-treatment activated the TLR4/NF-κB pathway, and transfecting pericytes with TLR4-small interfering RNA (siRNA) to block TLR4 signaling markedly restrained NLRP3 inflammasome over-activation. Injecting TAK-242 in rats alleviated neurological impairment caused by alcohol. Conclusion Long-term alcohol pre-treatment aggravated ischemic stroke-induced brain damage by activating NLRP3 inflammasome via TLR4/NF-κB signaling pathway in the pericytes.
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Affiliation(s)
- Kaixin Wang
- Department of Neurology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, People’s Republic of China
| | - Lingfei Yang
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, People’s Republic of China
| | - Qingsheng Li
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, People’s Republic of China
| | - Xuan Yang
- Department of Neurology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, People’s Republic of China
| | - Ziyi Chen
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, People’s Republic of China
| | - Yongyan Zhou
- Department of Electrocardiogram, Zhoukou Center Hospital, Zhoukou, People’s Republic of China
| | - Yanjie Jia
- Department of Neurology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, People’s Republic of China
| | - Zhe Gong
- Department of Neurology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, People’s Republic of China
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Albalawi FE, Alsharif I, Moawadh MS, Alkhoshaiban A, Falah Alshehri F, Albalawi AE, Althobaiti NA, Alharbi ZM, Almohaimeed HM. Immunomodulatory effects of Kaempferol on microglial and Macrophage cells during the progression of diabetic retinopathy. Int Immunopharmacol 2024; 133:112021. [PMID: 38626549 DOI: 10.1016/j.intimp.2024.112021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2024] [Revised: 04/01/2024] [Accepted: 04/03/2024] [Indexed: 04/18/2024]
Abstract
BACKGROUND Diabetic retinopathy (DR) stands as a prevalent secondary complication of diabetes, notably Type 1 Diabetes Mellitus (T1D), characterized by immune system involvement potentially impacting the retinal immune response mediated by microglia. Early stages of DR witness blood-retinal barrier permeabilization, facilitating peripheral immune cell interaction with the retinal immune system. Kaempferol (Kae), known for its potent anti-inflammatory activity, presents a promising avenue in DR treatment by targeting the immune mechanisms underlying its onset and progression. Our investigation delves into the molecular intricacies of innate immune cell interaction during DR progression and the attenuation of inflammatory processes pivotal to its pathology. METHODS Employing in vitro studies, we exposed HAPI microglial and J774.A1 macrophage cells to pro-inflammatory stimuli in the presence or absence of Kae. Ex vivo and in vivo experiments utilized BB rats, a T1D animal model. Retinal explants from BB rats were cultured with Kae, while intraperitoneal Kae injections were administered to BB rats for 15 days. Quantitative PCR, Western blotting, immunofluorescence, and Spectral Domain - Optical Coherence Tomography (SD-OCT) facilitated survival assessment, cellular signaling analysis, and inflammatory marker determination. RESULTS Results demonstrate Kae significantly mitigates inflammatory processes across in vitro, ex vivo, and in vivo DR models, primarily targeting immune cell responses. Kae administration notably inhibits proinflammatory responses during DR progression while promoting an anti-inflammatory milieu, chiefly through microglia-mediated synthesis of Arginase-1 and Hemeoxygenase-1(HO-1). In vivo, Kae administration effectively preserves retinal integrity amid DR progression. CONCLUSIONS Our findings elucidate the interplay between retinal and systemic immune cells in DR progression, underscoring a differential treatment response predominantly orchestrated by microglia's anti-inflammatory action. Kae treatment induces a phenotypic and functional shift in immune cells, delaying DR progression, thereby spotlighting microglial cells as a promising therapeutic target in DR management.
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Affiliation(s)
- Fahad Eid Albalawi
- Regional laboratory, blood bank and poisons centre, Sakaka 72346, Saudi Arabia; Medical College, Fahad Bin Sultan University, Tabuk 47721, Saudi Arabia.
| | - Ifat Alsharif
- Department of Biology, Jamoum University College, Umm Al-Qura University, 21955, Makkah, Saudi Arabia
| | - Mamdoh S Moawadh
- Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, University of Tabuk, Tabuk 71491, Saudi Arabia
| | | | - Faez Falah Alshehri
- Department of Medical Laboratories, College of Applied Medical Sciences, Ad Dawadimi-17464, Shaqra University, Saudi Arabia
| | - Aishah E Albalawi
- Faculty of science, Department of Biology, University of Tabuk, Tabuk 47913, Saudi Arabia
| | - Norah A Althobaiti
- Biology Department, College of Science and Humanities, Al Quwaiiyah, Shaqra University, Al Quwaiiyah 19257, Saudi Arabia
| | - Zeyad M Alharbi
- Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, University of Tabuk, Tabuk 71491, Saudi Arabia
| | - Hailah M Almohaimeed
- Department of Basic Science, College of Medicine, Princess Nourah bint Abdulrahman University, P.O.Box 84428, Riyadh 11671, Saudi Arabia
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Stuart CM, Varatharaj A, Zou Y, Darekar A, Domjan J, Gandini Wheeler-Kingshott CAM, Perry VH, Galea I. Systemic inflammation associates with and precedes cord atrophy in progressive multiple sclerosis. Brain Commun 2024; 6:fcae143. [PMID: 38712323 PMCID: PMC11073756 DOI: 10.1093/braincomms/fcae143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 02/05/2024] [Accepted: 04/17/2024] [Indexed: 05/08/2024] Open
Abstract
In preclinical models of multiple sclerosis, systemic inflammation has an impact on the compartmentalized inflammatory process within the central nervous system and results in axonal loss. It remains to be shown whether this is the case in humans, specifically whether systemic inflammation contributes to spinal cord or brain atrophy in multiple sclerosis. Hence, an observational longitudinal study was conducted to delineate the relationship between systemic inflammation and atrophy using magnetic resonance imaging: the SIMS (Systemic Inflammation in Multiple Sclerosis) study. Systemic inflammation and progression were assessed in people with progressive multiple sclerosis (n = 50) over two and a half years. Eligibility criteria included: (i) primary or secondary progressive multiple sclerosis; (ii) age ≤ 70; and (iii) Expanded Disability Status Scale ≤ 6.5. First morning urine was collected weekly to quantify systemic inflammation by measuring the urinary neopterin-to-creatinine ratio using a validated ultra-performance liquid chromatography mass spectrometry technique. The urinary neopterin-to-creatinine ratio temporal profile was characterized by short-term responses overlaid on a background level of inflammation, so these two distinct processes were considered as separate variables: background inflammation and inflammatory response. Participants underwent MRI at the start and end of the study, to measure cervical spinal cord and brain atrophy. Brain and cervical cord atrophy occurred on the study, but the most striking change was seen in the cervical spinal cord, in keeping with the corticospinal tract involvement that is typical of progressive disease. Systemic inflammation predicted cervical cord atrophy. An association with brain atrophy was not observed in this cohort. A time lag between systemic inflammation and cord atrophy was evident, suggesting but not proving causation. The association of the inflammatory response with cord atrophy depended on the level of background inflammation, in keeping with experimental data in preclinical models where the effects of a systemic inflammatory challenge on tissue injury depended on prior exposure to inflammation. A higher inflammatory response was associated with accelerated cord atrophy in the presence of background systemic inflammation below the median for the study population. Higher background inflammation, while associated with cervical cord atrophy itself, subdued the association of the inflammatory response with cord atrophy. Findings were robust to sensitivity analyses adjusting for potential confounders and excluding cases with new lesion formation. In conclusion, systemic inflammation associates with, and precedes, multiple sclerosis progression. Further work is needed to prove causation since targeting systemic inflammation may offer novel treatment strategies for slowing neurodegeneration in multiple sclerosis.
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Affiliation(s)
- Charlotte M Stuart
- Clinical Neurosciences, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
| | - Aravinthan Varatharaj
- Clinical Neurosciences, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
- Wessex Neurological Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | - Yukai Zou
- Clinical Neurosciences, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
- Department of Medical Physics, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | - Angela Darekar
- Department of Medical Physics, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | - Janine Domjan
- Wessex Neurological Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | - Claudia A M Gandini Wheeler-Kingshott
- Department of Neuroinflammation, Faculty of Brain Sciences, NMR Research Unit, Queen Square Multiple Sclerosis Centre, UCL Queen Square Institute of Neurology, University College London, London WC1B 5EH, UK
| | - V Hugh Perry
- School of Biological Sciences, University of Southampton, Southampton SO16 6YD, UK
| | - Ian Galea
- Clinical Neurosciences, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
- Wessex Neurological Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
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Li W, Tang T, Yao S, Zhong S, Fan Q, Zou T. Low-dose Lipopolysaccharide Alleviates Spinal Cord Injury-induced Neuronal Inflammation by Inhibiting microRNA-429-mediated Suppression of PI3K/AKT/Nrf2 Signaling. Mol Neurobiol 2024; 61:294-307. [PMID: 37605094 DOI: 10.1007/s12035-023-03483-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 07/05/2023] [Indexed: 08/23/2023]
Abstract
This study investigated the impact of low-dose lipopolysaccharide (LPS) on spinal cord injury (SCI) and the potential molecular mechanism. Rats were randomly assigned to four groups: Sham, SCI, SCI + LPS, and SCI + LPS + agomir. Allen's weight-drop method was used to establish an in vivo SCI model. The Basso Bcattie Bresnahan rating scale was employed to monitor locomotor function. An in vitro SCI model was constructed by subjecting PC12 cells to oxygen and glucose deprivation/ reoxygenation (OGD/R). Enzyme-linked immunosorbent assay (ELISA) was applied for the determination interleukin (IL)-1β and IL-6. The dual luciferase reporter assay was used to validate the targeting of microRNA (miR)-429 with PI3K. Immunohistochemical staining was used to assess the expression of PI3K, phosphorylated AKT and Nrf2 proteins. The Nrf2-downstream anti-oxidative stress proteins, OH-1 and NQO1, were detected by western blot assay. MiR-429 expression was detected by fluorescence in situ hybridization and real-time quantitative reverse transcription PCR. In vitro, low-dose LPS decreased miR-429 expression, activated PI3K/AKT/Nrf2, inhibited oxidative stress and inflammation, and attenuated SCI. MiR-429 was found to target and negatively regulate PI3K. Inhibition of miR-429 suppressed low-dose LPS-mediated oxidative stress and inflammation via activation of the PI3K/AKT/Nrf2 pathway. In vivo, miR-429 was detectable in neurons. Inhibition of miR-429 blocked low-dose LPS-mediated oxidative stress and inflammation via activation of the PI3K/AKT/Nrf2 pathway. Overall, low-dose LPS was found to alleviate SCI-induced neuronal oxidative stress and inflammatory response by down-regulating miR-429 to activate the PI3K/AKT/Nrf2 pathway.
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Affiliation(s)
- Weichao Li
- Department of Orthopedic Surgery, The First People's Hospital of Yunnan province, Affiliated Hospital of Kunming University of Science and Technology, Kunming, 650032, China
- Faculty of Medical Science, Kunming University of Science and Technology, Kunming, 650500, China
- Yunnan Key Laboratory of Digital Orthopaedics, Kunming, 650032, China
| | - Tao Tang
- Faculty of Medical Science, Kunming University of Science and Technology, Kunming, 650500, China
| | - Shaoping Yao
- Department of Orthopedic Surgery, The First People's Hospital of Yunnan province, Affiliated Hospital of Kunming University of Science and Technology, Kunming, 650032, China
- Yunnan Key Laboratory of Digital Orthopaedics, Kunming, 650032, China
| | - Shixiao Zhong
- Faculty of Medical Science, Kunming University of Science and Technology, Kunming, 650500, China
| | - Qianbo Fan
- Faculty of Medical Science, Kunming University of Science and Technology, Kunming, 650500, China
| | - Tiannan Zou
- Department of Orthopedic Surgery, The First People's Hospital of Yunnan province, Affiliated Hospital of Kunming University of Science and Technology, Kunming, 650032, China.
- Yunnan Key Laboratory of Digital Orthopaedics, Kunming, 650032, China.
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Le YP, Saito K, Parajuli B, Sakai K, Kubota Y, Miyakawa M, Shinozaki Y, Shigetomi E, Koizumi S. Severity of Peripheral Infection Differentially Affects Brain Functions in Mice via Microglia-Dependent and -Independent Mechanisms. Int J Mol Sci 2023; 24:17597. [PMID: 38139424 PMCID: PMC10743593 DOI: 10.3390/ijms242417597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/14/2023] [Accepted: 12/14/2023] [Indexed: 12/24/2023] Open
Abstract
Peripheral infection induces inflammation in peripheral tissues and the brain, impacting brain function. Glial cells are key players in this process. However, the effects of peripheral infection on glial activation and brain function remain unknown. Here, we showed that varying degrees of peripheral infection had different effects on the regulation of brain functions by microglia-dependent and -independent mechanisms. Acute mild infection (one-day LPS challenge: 1LPS) exacerbated middle cerebral artery occlusion (MCAO) injury, and severe infection (four-day LPS challenge: 4LPS) for one week suppressed it. MCAO injury was assessed by triphenyltetrazolium chloride staining. We observed early activation of microglia in the 1LPS and 4LPS groups. Depleting microglia with a colony-stimulating factor-1 receptor (CSF1R) antagonist had no effect on 1LPS-induced brain injury exacerbation but abolished 4LPS-induced protection, indicating microglial independence and dependence, respectively. Microglia-independent exacerbation caused by 1LPS involved peripheral immune cells including macrophages. RNA sequencing analysis of 4LPS-treated microglia revealed increased factors related to anti-inflammatory and neuronal tissue repair, suggesting their association with the protective effect. In conclusion, varying degrees of peripheral inflammation had contradictory effects (exacerbation vs. protection) on MCAO, which may be attributed to microglial dependence. Our findings highlight the significant impact of peripheral infection on brain function, particularly in relation to glial cells.
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Affiliation(s)
- Yen-Phung Le
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Kozo Saito
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Bijay Parajuli
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Kent Sakai
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Yuto Kubota
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Miho Miyakawa
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Youichi Shinozaki
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Eiji Shigetomi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Schuichi Koizumi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
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Hu J, Huang K, Bao F, Zhong S, Fan Q, Li W. Low-dose lipopolysaccharide inhibits spinal cord injury-induced neuronal apoptosis by regulating autophagy through the lncRNA MALAT1/Nrf2 axis. PeerJ 2023; 11:e15919. [PMID: 37663283 PMCID: PMC10470450 DOI: 10.7717/peerj.15919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 07/27/2023] [Indexed: 09/05/2023] Open
Abstract
Background Spinal cord injury (SCI) is a neurological disease associated with a high disability rate. Low-dose lipopolysaccharide (LPS) has been reported to activate cross-immune tolerance and alleviate the effects of various traumatic stimuli. The present study aimed to explore the effect of LPS on SCI and the potential molecular mechanism. Methods Male Sprague-Dawley (SD) rats were used to established an in vivo SCI model and were intraperitoneally injected with lentivirus particles encoding a MALAT1 small interfering RNA (siRNA) on day 10 prior to SCI and with 0.2 mg/kg LPS 72 h prior to SCI. Basso, Beattie, and Bresnahan (BBB) scoring; HE staining; and TUNEL assay were used to assess neurological function and pathophysiological changes. Western blot and immunohistochemistry (IHC) were used to detect cell autophagy and Nrf2 nuclear translocation. PC12 cells were exposed to oxygen-glucose deprivation/reoxygenation (OGD/R) to establish an in vitro SCI model. In vitro SCI model cells were pretreated with LPS and transfected with siMALAT1 or MALAT1 overexpression plasmid aimed at knocking down MALAT1 or overexpressing MALAT1. The cell counting kit-8 (CCK-8) assay was used to measure the toxicity of LPS towards PC12 cells. Flow cytometry and immunofluorescence analysis were performed to investigate cell apoptosis and Nrf2 nuclear translocation. Results SCI rats preconditioned with low-dose LPS had higher BBB scores, reduced SCI injury, increased MALAT1 expression and activated autophagy and Nrf2 nuclear translocation in the in vivo SCI model. In the in vitro SCI model, low-dose LPS treatment suppressed the apoptotic ratio of PC12 cells, increased MALAT1 expression, activated autophagy, and promoted Nrf2 nuclear translocation. Silencing MALAT1 exacerbated OGD/R injury in vitro and weakened the protective effect of low-dose LPS. Overexpression of MALAT1 inhibits OGD/R-induced apoptosis by inducing autophagy and promoting Nrf2 nuclear translocation. This was also been confirmed in animal experiments, silencing MALAT1 blocked the promotion of Nrf2 by low-dose LPS and the alleviated of SCI apoptosis. Conclusions Low-dose LPS exhibited a protective role on SCI by activating autophagy and suppressing nerve cell apoptosis via the lncRNA MALAT1/Nrf2 axis.
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Affiliation(s)
- Jianhua Hu
- Orthopedic Surgery, The First People’s Hospital of Yunnan Province, Affiliated Hospital of Kunming University of Science and Technology, Kunming, China
- Faculty of Medical Science, Kunming University of Science and Technology, Kunming, China
| | - Kun Huang
- Orthopedic Surgery, The First People’s Hospital of Yunnan Province, Affiliated Hospital of Kunming University of Science and Technology, Kunming, China
| | - Feilong Bao
- Faculty of Medical Science, Kunming University of Science and Technology, Kunming, China
- Yunnan Key Laboratory of Digital Orthopaedics, Kunming, China
| | - Shixiao Zhong
- Faculty of Medical Science, Kunming University of Science and Technology, Kunming, China
- Yunnan Key Laboratory of Digital Orthopaedics, Kunming, China
| | - Qianbo Fan
- Faculty of Medical Science, Kunming University of Science and Technology, Kunming, China
- Yunnan Key Laboratory of Digital Orthopaedics, Kunming, China
| | - Weichao Li
- Orthopedic Surgery, The First People’s Hospital of Yunnan Province, Affiliated Hospital of Kunming University of Science and Technology, Kunming, China
- Faculty of Medical Science, Kunming University of Science and Technology, Kunming, China
- Yunnan Key Laboratory of Digital Orthopaedics, Kunming, China
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8
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Gao X, Yang H, Xiao W, Su J, Zhang Y, Wang H, Ni W, Gu Y. Modified exosomal SIRPα variants alleviate white matter injury after intracerebral hemorrhage via microglia/macrophages. Biomater Res 2022; 26:67. [DOI: 10.1186/s40824-022-00311-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 10/27/2022] [Indexed: 11/28/2022] Open
Abstract
Abstract
Background
Despite limited efficiency, modulation of microglia/macrophages has shown to attenuate neuroinflammation after intracerebral hemorrhage (ICH). In this context, we evaluated the efficacy of modified exosomal signal regulatory protein α (SIRPα) variants (SIRPα-v Exos) in microglia/macrophages and neuroinflammation-associated white matter injury after ICH.
Methods
SIRPα-v Exos were engineered to block CD47-SIRPα interactions. After obtaining SIRPα-v Exos from lentivirus-infected mesenchymal stem cells, C57BL/6 mice suffering from ICH underwent consecutive intravenous injections of SIRPα-v Exos (6 mg/kg) for 14 days. Afterwards, the volume of hematoma and neurological dysfunctions were assessed in mice continuously until 35 days after ICH. In addition, demyelination, electrophysiology and neuroinflammation were evaluated. Furthermore, the mechanisms of microglial regulation by SIRPα-v Exos were investigated in vitro under coculture conditions.
Results
The results demonstrated that the clearance of hematoma in mice suffering from ICH was accelerated after SIRPα-v Exo treatment. SIRPα-v Exos improved long-term neurological dysfunction by ameliorating white matter injury. In addition, SIRPα-v Exos recruited regulatory T cells (Tregs) to promote M2 polarization of microglia/macrophages in the peri-hematoma tissue. In vitro experiments further showed that SIRPα-v Exos regulated primary microglia in a direct and indirect manner in synergy with Tregs.
Conclusion
Our studies revealed that SIRPα-v Exos could accelerate the clearance of hematoma and ameliorate secondary white matter injury after ICH through regulation of microglia/macrophages. SIRPα-v Exos may become a promising treatment for ICH in clinical practice.
Graphical Abstract
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9
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Hashemizadeh S, Hosseindoost S, Omidi A, Aminianfar H, Ebrahimi-Barough S, Ai J, Arjmand B, Hadjighassem M. Novel therapeutic approach to slow down the inflammatory cascade in acute/subacute spinal cord injury: Early immune therapy with lipopolysaccharide enhanced neuroprotective effect of combinational therapy of granulocyte colony-stimulating factor and bone-marrow mesenchymal stem cell in spinal cord injury. Front Cell Neurosci 2022; 16:993019. [PMID: 36505513 PMCID: PMC9727083 DOI: 10.3389/fncel.2022.993019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 10/31/2022] [Indexed: 11/24/2022] Open
Abstract
Bone-marrow mesenchymal stem cells (BM-MSCs) have not yet proven any significant therapeutic efficacy in spinal cord injury (SCI) clinical trials, due to the hostile microenvironment of the injured spinal cord at the acute phase. This study aims to modulate the inflammatory milieu by lipopolysaccharide (LPS) and granulocyte colony-stimulating factor (G-CSF) to improve the BM-MSCs therapy. For this purpose, we determined the optimum injection time and sub-toxic dosage of LPS following a T10 contusion injury. Medium-dose LPS administration may result in a local anti-inflammatory beneficial role. This regulatory role is associated with an increase in NF-200-positive cells, significant tissue sparing, and improvement in functional recovery compared to the SCI control group. The second aim was to examine the potential ability of LPS and LPS + G-CSF combination therapy to modulate the lesion site before BM-MSC (1 × 105 cells) intra-spinal injection. Our results demonstrated combination therapy increased potency to enhance the anti-inflammatory response (IL-10 and Arg-1) and decrease inflammatory markers (TNF-α and CD86) and caspase-3 compared to BM-MSC monotherapy. Histological analysis revealed that combination groups displayed better structural remodeling than BM-MSC monotherapy. In addition, Basso-Beattie-Bresnahan (BBB) scores show an increase in motor recovery in all treatment groups. Moreover, drug therapy shows faster recovery than BM-MSC monotherapy. Our results suggest that a sub-toxic dose of LPS provides neuroprotection to SCI and can promote the beneficial effect of BM-MSC in SCI. These findings suggest that a combination of LPS or LPS + G-CSF prior BM-MSC transplantation is a promising approach for optimizing BM-MSC-based strategies to treat SCI. However, because of the lack of some methodological limitations to examine the survival rate and ultimate fate of transplanted BM-MSCs followed by LPS administration in this study, further research needs to be done in this area. The presence of only one-time point for evaluating the inflammatory response (1 week) after SCI can be considered as one of the limitations of this study. We believed that the inclusion of additional time points would provide more information about the effect of our combination therapy on the microglia/macrophage polarization dynamic at the injured spinal cord.
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Affiliation(s)
- Shiva Hashemizadeh
- Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Saereh Hosseindoost
- Pain Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Ameneh Omidi
- Department of Anatomical Sciences, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | | | - Somayeh Ebrahimi-Barough
- Department of Tissue Engineering and Applied Cell Sciences, Faculty of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Jafar Ai
- Department of Tissue Engineering and Applied Cell Sciences, Faculty of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Babak Arjmand
- Cell Therapy and Regenerative Medicine Research Center, Endocrinology and Metabolism Molecular-Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran,Metabolomics and Genomics Research Center, Endocrinology and Metabolism Molecular-Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Mahmoudreza Hadjighassem
- Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran,Department of Neuroscience and Addiction Studies, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran,*Correspondence: Mahmoudreza Hadjighassem,
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10
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Slater PG, Domínguez-Romero ME, Villarreal M, Eisner V, Larraín J. Mitochondrial function in spinal cord injury and regeneration. Cell Mol Life Sci 2022; 79:239. [PMID: 35416520 PMCID: PMC11072423 DOI: 10.1007/s00018-022-04261-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 03/16/2022] [Accepted: 03/17/2022] [Indexed: 12/21/2022]
Abstract
Many people around the world suffer from some form of paralysis caused by spinal cord injury (SCI), which has an impact on quality and life expectancy. The spinal cord is part of the central nervous system (CNS), which in mammals is unable to regenerate, and to date, there is a lack of full functional recovery therapies for SCI. These injuries start with a rapid and mechanical insult, followed by a secondary phase leading progressively to greater damage. This secondary phase can be potentially modifiable through targeted therapies. The growing literature, derived from mammalian and regenerative model studies, supports a leading role for mitochondria in every cellular response after SCI: mitochondrial dysfunction is the common event of different triggers leading to cell death, cellular metabolism regulates the immune response, mitochondrial number and localization correlate with axon regenerative capacity, while mitochondrial abundance and substrate utilization regulate neural stem progenitor cells self-renewal and differentiation. Herein, we present a comprehensive review of the cellular responses during the secondary phase of SCI, the mitochondrial contribution to each of them, as well as evidence of mitochondrial involvement in spinal cord regeneration, suggesting that a more in-depth study of mitochondrial function and regulation is needed to identify potential targets for SCI therapeutic intervention.
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Affiliation(s)
- Paula G Slater
- Center for Aging and Regeneration, Departamento de Biología Celular Y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, 8331150, Santiago, Chile.
| | - Miguel E Domínguez-Romero
- Center for Aging and Regeneration, Departamento de Biología Celular Y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, 8331150, Santiago, Chile
| | - Maximiliano Villarreal
- Center for Aging and Regeneration, Departamento de Biología Celular Y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, 8331150, Santiago, Chile
| | - Verónica Eisner
- Center for Aging and Regeneration, Departamento de Biología Celular Y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, 8331150, Santiago, Chile
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, 8331150, Santiago, Chile
| | - Juan Larraín
- Center for Aging and Regeneration, Departamento de Biología Celular Y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, 8331150, Santiago, Chile
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11
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Gao T, Huang F, Wang W, Xie Y, Wang B. Interleukin-10 genetically modified clinical-grade mesenchymal stromal cells markedly reinforced functional recovery after spinal cord injury via directing alternative activation of macrophages. Cell Mol Biol Lett 2022; 27:27. [PMID: 35300585 PMCID: PMC8931978 DOI: 10.1186/s11658-022-00325-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 02/22/2022] [Indexed: 12/19/2022] Open
Abstract
Background After spinal cord injury (SCI), dysregulated or nonresolving inflammatory processes can severely disturb neuronal homeostasis and drive neurodegeneration. Although mesenchymal stromal cell (MSC)-based therapies have showed certain therapeutic efficacy, no MSC therapy has reached its full clinical goal. In this study, we examine interleukin-10 (IL10) genetically modified clinical-grade MSCs (IL10-MSCs) and evaluate their clinical safety, effectiveness, and therapeutic mechanism in a completely transected SCI mouse model. Methods We established stable IL10-overexpressing human umbilical-cord-derived MSCs through electric transduction and screened out clinical-grade IL10-MSCs according to the criteria of cell-based therapeutic products, which were applied to mice with completely transected SCI by repeated tail intravenous injections. Then we comprehensively investigated the motor function, histological structure, and nerve regeneration in SCI mice, and further explored the potential therapeutic mechanism after IL10-MSC treatment. Results IL10-MSC treatment markedly reinforced locomotor improvement, accompanied with decreased lesion volume, regeneration of axons, and preservation of neurons, compared with naïve unmodified MSCs. Further, IL10-MSC transplantation increased the ratio of microglia to infiltrated alternatively activated macrophages (M2), and reduced the ratio of classically activated macrophages (M1) at the injured spinal cord, meanwhile increasing the percentage of Treg and Th2 cells, and reducing the percentage of Th1 cells in the peripheral circulatory system. In addition, IL10-MSC administration could prevent apoptosis and promote neuron differentiation of neural stem cells (NSCs) under inflammatory conditions in vitro. Conclusions IL10-MSCs exhibited a reliable safety profile and demonstrated promising therapeutic efficacy in SCI compared with naïve MSCs, providing solid support for future clinical application of genetically engineered MSCs. Supplementary Information The online version contains supplementary material available at 10.1186/s11658-022-00325-9.
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Affiliation(s)
- Tianyun Gao
- Center for Clinic Stem Cell Research, the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, Jiangsu, China
| | - Feifei Huang
- Center for Clinic Stem Cell Research, the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, Jiangsu, China
| | - Wenqing Wang
- Center for Clinic Stem Cell Research, the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, Jiangsu, China
| | - Yuanyuan Xie
- Center for Clinic Stem Cell Research, the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, Jiangsu, China
| | - Bin Wang
- Center for Clinic Stem Cell Research, the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, Jiangsu, China.
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12
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Nemeth DP, Liu X, McKim DB, DiSabato DJ, Oliver B, Herd A, Katta A, Negray CE, Floyd J, McGovern S, Pruden PS, Zhutang F, Smirnova M, Godbout JP, Sheridan J, Quan N. Dynamic Interleukin-1 Receptor Type 1 Signaling Mediates Microglia-Vasculature Interactions Following Repeated Systemic LPS. J Inflamm Res 2022; 15:1575-1590. [PMID: 35282272 PMCID: PMC8906862 DOI: 10.2147/jir.s350114] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 02/16/2022] [Indexed: 01/18/2023] Open
Abstract
Introduction Lipopolysaccharide (LPS) preconditioning involves repeated, systemic, and sub-threshold doses of LPS, which induces a neuroprotective state within the CNS, thus preventing neuronal death and functional losses. Recently, proinflammatory cytokine, Interleukin-1 (IL-1), and its primary signaling partner, interleukin-1 receptor type 1 (IL-1R1), have been associated with neuroprotection in the CNS. However, it is still unknown how IL-1/IL-1R1 signaling impacts the processes associated with neuroprotection. Methods Using our IL-1R1 restore genetic mouse model, mouse lines were generated to restrict IL-1R1 expression either to endothelia (Tie2-Cre-Il1r1r/r) or microglia (Cx3Cr1-Cre-Il1r1 r/r), in addition to either global ablation (Il1r1 r/r) or global restoration of IL-1R1 (Il1r1 GR/GR). The LPS preconditioning paradigm consisted of four daily i.p. injections of LPS at 1 mg/kg (4d LPS). 24 hrs following the final i.p. LPS injection, tissue was collected for qPCR analysis, immunohistochemistry, or FAC sorting. Results Following 4d LPS, we found multiple phenotypes that are dependent on IL-1R1 signaling such as microglia morphology alterations, increased microglial M2-like gene expression, and clustering of microglia onto the brain vasculature. We determined that 4d LPS induces microglial morphological changes, clustering at the vasculature, and gene expression changes are dependent on endothelial IL-1R1, but not microglial IL-1R1. A novel observation was the induction of microglial IL-1R1 (mIL-1R1) following 4d LPS. The induced mIL-1R1 permits a unique response to central IL-1β: the mIL-1R1 dependent induction of IL-1R1 antagonist (IL-1RA) and IL-1β gene expression. Analysis of RNA sequencing datasets revealed that mIL-1R1 is also induced in neurodegenerative diseases. Discussion Here, we have identified cell type-specific IL-1R1 mediated mechanisms, which may contribute to the neuroprotection observed in LPS preconditioning. These findings identify key cellular and molecular contributors in LPS-induced neuroprotection.
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Affiliation(s)
- Daniel P Nemeth
- College of Dentistry, The Ohio State University, Columbus, OH, USA,Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA,Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, FL, USA,Correspondence: Daniel P Nemeth; Ning Quan, 5353 Parkside Drive, Jupiter, FL, 33458, USA, Email ;
| | - Xiaoyu Liu
- Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, FL, USA
| | - Daniel B McKim
- Department of Animal Sciences, University of Illinois Urbana-Champaign, Champaign, IL, USA
| | - Damon J DiSabato
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA,Department of Neuroscience, The Ohio State University, Columbus, OH, USA
| | - Braedan Oliver
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA
| | - Anu Herd
- Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, FL, USA
| | - Asish Katta
- College of Dentistry, The Ohio State University, Columbus, OH, USA
| | - Christina E Negray
- College of Dentistry, The Ohio State University, Columbus, OH, USA,Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA
| | - James Floyd
- Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, FL, USA
| | - Samantha McGovern
- Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, FL, USA
| | - Paige S Pruden
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA
| | - Feiyang Zhutang
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA
| | - Maria Smirnova
- Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, FL, USA
| | - Jonathan P Godbout
- Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA,Department of Neuroscience, The Ohio State University, Columbus, OH, USA
| | - John Sheridan
- College of Dentistry, The Ohio State University, Columbus, OH, USA,Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA
| | - Ning Quan
- Stiles-Nicholson Brain Institute, Florida Atlantic University, Jupiter, FL, USA
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13
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Mizobuchi H, Soma GI. Low-dose lipopolysaccharide as an immune regulator for homeostasis maintenance in the central nervous system through transformation to neuroprotective microglia. Neural Regen Res 2021; 16:1928-1934. [PMID: 33642362 PMCID: PMC8343302 DOI: 10.4103/1673-5374.308067] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 10/26/2020] [Accepted: 12/16/2020] [Indexed: 12/25/2022] Open
Abstract
Microglia, which are tissue-resident macrophages in the brain, play a central role in the brain innate immunity and contribute to the maintenance of brain homeostasis. Lipopolysaccharide is a component of the outer membrane of gram-negative bacteria, and activates immune cells including microglia via Toll-like receptor 4 signaling. Lipopolysaccharide is generally known as an endotoxin, as administration of high-dose lipopolysaccharide induces potent systemic inflammation. Also, it has long been recognized that lipopolysaccharide exacerbates neuroinflammation. In contrast, our study revealed that oral administration of lipopolysaccharide ameliorates Alzheimer's disease pathology and suggested that neuroprotective microglia are involved in this phenomenon. Additionally, other recent studies have accumulated evidence demonstrating that controlled immune training with low-dose lipopolysaccharide prevents neuronal damage by transforming the microglia into a neuroprotective phenotype. Therefore, lipopolysaccharide may not a mere inflammatory inducer, but an immunomodulator that can lead to neuroprotective effects in the brain. In this review, we summarized current studies regarding neuroprotective microglia transformed by immune training with lipopolysaccharide. We state that microglia transformed by lipopolysaccharide preconditioning cannot simply be characterized by their general suppression of proinflammatory mediators and general promotion of anti-inflammatory mediators, but instead must be described by their complex profile comprising various molecules related to inflammatory regulation, phagocytosis, neuroprotection, anti-apoptosis, and antioxidation. In addition, microglial transformation seems to depend on the dose of lipopolysaccharide used during immune training. Immune training of neuroprotective microglia using low-dose lipopolysaccharide, especially through oral lipopolysaccharide administration, may represent an innovative prevention or treatment for neurological diseases; however more vigorous studies are still required to properly modulate these treatments.
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Affiliation(s)
- Haruka Mizobuchi
- Control of Innate Immunity, Technology Research Association, Kagawa, Japan
| | - Gen-Ichiro Soma
- Control of Innate Immunity, Technology Research Association, Kagawa, Japan
- Macrophi Inc., Kagawa, Japan
- Research Institute for Healthy Living, Niigata University of Pharmacy and Applied Life Sciences, Niigata, Japan
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14
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Mizobuchi H, Yamamoto K, Yamashita M, Inagawa H, Kohchi C, Soma GI. Prevention of streptozotocin‑induced Neuro‑2a cell death by C8‑B4 microglia transformed with repetitive low‑dose lipopolysaccharide. Mol Med Rep 2021; 24:687. [PMID: 34328201 DOI: 10.3892/mmr.2021.12328] [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: 02/02/2021] [Accepted: 06/29/2021] [Indexed: 11/05/2022] Open
Abstract
Diabetes‑associated neuronal dysfunction (DAND) is one of the serious complications of diabetes, but there is currently no remedy for it. Streptozotocin [2‑deoxy‑2‑(3‑methy1‑3‑nitrosoureido) D‑glucopyranose; STZ] is one of the most well‑established diabetes inducers and has been used in vivo and in vitro DAND models. The aim of the present study was to demonstrate that C8‑B4 microglia transformed by the stimulus of repetitive low‑dose lipopolysaccharide (LPSx3‑microglia) prevent STZ‑induced Neuro‑2a neuronal cell death in vitro. The ELISA results showed that neurotrophin‑4/5 (NT‑4/5) secretion was promoted in LPSx3‑microglia and the cell viability assay with trypan blue staining revealed that the culture supernatant of LPSx3‑microglia prevented STZ‑induced neuronal cell death. In addition, reverse transcription‑quantitative PCR showed that neurons treated with the culture supernatant of LPSx3‑microglia promoted the gene expression of B‑cell lymphoma‑extra large and glucose‑dependent insulinotropic polypeptide receptor. Furthermore, the inhibition of tyrosine kinase receptor B, a receptor of NT‑4/5, suppressed the neuroprotective effect of LPSx3‑microglia. Taken together, the present study demonstrated that LPSx3‑microglia prevent STZ‑induced neuronal death and that NT‑4/5 may be involved in the neuroprotective mechanism of LPSx3‑microglia.
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Affiliation(s)
- Haruka Mizobuchi
- Control of Innate Immunity, Collaborative Innovation Partnership, Takamatsu‑shi, Kagawa 761‑0301, Japan
| | - Kazushi Yamamoto
- Control of Innate Immunity, Collaborative Innovation Partnership, Takamatsu‑shi, Kagawa 761‑0301, Japan
| | - Masashi Yamashita
- Control of Innate Immunity, Collaborative Innovation Partnership, Takamatsu‑shi, Kagawa 761‑0301, Japan
| | - Hiroyuki Inagawa
- Control of Innate Immunity, Collaborative Innovation Partnership, Takamatsu‑shi, Kagawa 761‑0301, Japan
| | - Chie Kohchi
- Control of Innate Immunity, Collaborative Innovation Partnership, Takamatsu‑shi, Kagawa 761‑0301, Japan
| | - Gen-Ichiro Soma
- Control of Innate Immunity, Collaborative Innovation Partnership, Takamatsu‑shi, Kagawa 761‑0301, Japan
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15
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Sangaran PG, Ibrahim ZA, Chik Z, Mohamed Z, Ahmadiani A. Lipopolysaccharide Pre-conditioning Attenuates Pro-inflammatory Responses and Promotes Cytoprotective Effect in Differentiated PC12 Cell Lines via Pre-activation of Toll-Like Receptor-4 Signaling Pathway Leading to the Inhibition of Caspase-3/Nuclear Factor-κappa B Pathway. Front Cell Neurosci 2021; 14:598453. [PMID: 33551748 PMCID: PMC7862565 DOI: 10.3389/fncel.2020.598453] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 12/15/2020] [Indexed: 12/11/2022] Open
Abstract
Lipopolysacharide (LPS) pre-conditioning (PC), has been shown to exert protective effects against cytotoxic effects. Therefore, we hypothesized, the tolerance produced by LPS PC will be resulted by the alterations and modifications in gene and protein expression. With reference to the results of MTT assays, AO/PI staining, and Annexin V-FITC analyses of LPS concentration (0.7815-50 μg/mL) and time-dependent (12-72 h) experiments, the pre-exposure to 3 μg/mL LPS for 12 h protected the differentiated PC12 cells against 0.75 mg/mL LPS apoptotic concentration. LPS-treated cells secreted more inflammatory cytokines like IL-1α, IL-1β, IL-2, IL-3, IL-4, IL-6, IL-17, IFN-γ, and TNF-α than LPS-PC cells. The production of inflammatory mediators ROS and NO was also higher in the LPS-induced cells compared to LPS-PC cells. Conversely, anti-inflammatory cytokines (like IL-10, IL-13, CNTF, and IL-1Ra) were upregulated in the LPS-PC cells but not in the LPS-induced cells. Meanwhile, the LPS initiated caspase-8 which in turn activates effector caspase 3/7. When the activities of caspases in the LPS-induced cells were inhibited using z-VADfmk and z-DEVDfmk, the expressions of c-MYC and Hsp70 were increased, but p53 was reduced. The potential molecules associated with protective and destructive effect was measured by RT2 Profiler PCR array to elucidate the signaling pathways and suggested inhibition NF-κB/caspase-3 signaling pathway regulates the cytoprotective genes and proto-oncogenes. In conclusion, this study provides a basis for future research to better understand the molecular mechanism underlying LPS pre-conditioning /TLR4 pre-activation and its functional role in offering cytoprotective response in neuronal environment.
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Affiliation(s)
- Pushpa Gandi Sangaran
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Zaridatul Aini Ibrahim
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Zamri Chik
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Zahurin Mohamed
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Abolhassan Ahmadiani
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, Evin, Tehran, Iran
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Sangaran PG, Ibrahim ZA, Chik Z, Mohamed Z, Ahmadiani A. LPS Preconditioning Attenuates Apoptosis Mechanism by Inhibiting NF-κB and Caspase-3 Activity: TLR4 Pre-activation in the Signaling Pathway of LPS-Induced Neuroprotection. Mol Neurobiol 2021; 58:2407-2422. [PMID: 33421016 DOI: 10.1007/s12035-020-02227-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Accepted: 11/24/2020] [Indexed: 12/11/2022]
Abstract
Neuroinflammation, an inflammatory response within the nervous system, has been shown to be implicated in the progression of various neurodegenerative diseases. Recent in vivo studies showed that lipopolysaccharide (LPS) preconditioning provides neuroprotection by activating Toll-like receptor 4 (TLR4), one of the members for pattern recognition receptor (PRR) family that play critical role in host response to tissue injury, infection, and inflammation. Pre-exposure to low dose of LPS could confer a protective state against cellular apoptosis following subsequent stimulation with LPS at higher concentration, suggesting a role for TLR4 pre-activation in the signaling pathway of LPS-induced neuroprotection. However, the precise molecular mechanism associated with this protective effect is not well understood. In this article, we provide an overall review of the current state of our knowledge about LPS preconditioning in attenuating apoptosis mechanism and conferring neuroprotection via TLR4 signaling pathway.
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Affiliation(s)
- Pushpa Gandi Sangaran
- Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Zaridatul Aini Ibrahim
- Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Zamri Chik
- Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Zahurin Mohamed
- Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Abolhassan Ahmadiani
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, Evin, PO Box 19839-63113, Tehran, Iran.
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Gu Y, Ye T, Tan P, Tong L, Ji J, Gu Y, Shen Z, Shen X, Lu X, Huang C. Tolerance-inducing effect and properties of innate immune stimulation on chronic stress-induced behavioral abnormalities in mice. Brain Behav Immun 2021; 91:451-471. [PMID: 33157258 DOI: 10.1016/j.bbi.2020.11.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 10/29/2020] [Accepted: 11/01/2020] [Indexed: 02/08/2023] Open
Abstract
Over-activation of the innate immune system constitutes a risk factor for the development of nervous system disorders but may reduce the severity of these disorders by inducing tolerance effect. Here, we studied the tolerance-inducing effect and properties of innate immune stimulation on chronic social defeat stress (CSDS)-induced behavioral abnormalities in mice. A single injection of the innate immune enhancer lipopolysaccharide (LPS) one day before stress exposure prevented CSDS-induced impairment in social interaction and increased immobility time in the tail suspension test and forced swimming test. This effect was observed at varying doses (100, 500, and 1000 μg/kg) and peaked at 100 μg/kg. A single LPS injection (100 μg/kg) either one or five but not ten days before stress exposure prevented CSDS-induced behavioral abnormalities. A second LPS injection ten days after the first LPS injection, or a 2 × or 4 × LPS injections ten days before stress exposure also induced tolerance against stress-induced behavioral abnormalities. Our results furthermore showed that a single LPS injection one day before stress exposure skewed the neuroinflammatory response in the hippocampus and prefrontal cortex of CSDS-exposed mice toward an anti-inflammatory phenotype. Inhibiting the central innate immune response by pretreatment with minocycline or PLX3397 abrogated the tolerance-inducing effect of LPS preconditioning on CSDS-induced behavioral abnormalities and neuroinflammatory responses in the brain. These results provide evidence for a prophylactic effect of innate immune stimulation on stress-induced behavioral abnormalities via changes in microglial activation, which may help develop novel strategies for the prevention of stress-induced psychological disorders.
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Affiliation(s)
- Yue Gu
- Department of Pharmacology, School of Pharmacy, Nantong University, #19 Qixiu Road, Nantong 226001, Jiangsu, China
| | - Ting Ye
- Department of Pharmacology, School of Pharmacy, Nantong University, #19 Qixiu Road, Nantong 226001, Jiangsu, China
| | - Pingping Tan
- Department of Pharmacology, School of Pharmacy, Nantong University, #19 Qixiu Road, Nantong 226001, Jiangsu, China
| | - Lijuan Tong
- Department of Pharmacology, School of Pharmacy, Nantong University, #19 Qixiu Road, Nantong 226001, Jiangsu, China
| | - Jianlin Ji
- Department of Pharmacology, School of Pharmacy, Nantong University, #19 Qixiu Road, Nantong 226001, Jiangsu, China
| | - Yiming Gu
- Department of Pharmacology, School of Pharmacy, Nantong University, #19 Qixiu Road, Nantong 226001, Jiangsu, China
| | - Zhongxia Shen
- Department of Psychosomatic and Psychiatric Diseases, Huzhou Third Municipal Hospital Huzhou, the Affiliated Hospital of Huzhou University, #2088 Tiaoxi East Road, Huzhou 313000, Zhejiang, China
| | - Xinhua Shen
- Department of Psychosomatic and Psychiatric Diseases, Huzhou Third Municipal Hospital Huzhou, the Affiliated Hospital of Huzhou University, #2088 Tiaoxi East Road, Huzhou 313000, Zhejiang, China
| | - Xu Lu
- Department of Pharmacology, School of Pharmacy, Nantong University, #19 Qixiu Road, Nantong 226001, Jiangsu, China.
| | - Chao Huang
- Department of Pharmacology, School of Pharmacy, Nantong University, #19 Qixiu Road, Nantong 226001, Jiangsu, China.
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Serial Systemic Injections of Endotoxin (LPS) Elicit Neuroprotective Spinal Cord Microglia through IL-1-Dependent Cross Talk with Endothelial Cells. J Neurosci 2020; 40:9103-9120. [PMID: 33051350 DOI: 10.1523/jneurosci.0131-20.2020] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 09/13/2020] [Accepted: 09/17/2020] [Indexed: 12/12/2022] Open
Abstract
Microglia are dynamic immunosurveillance cells in the CNS. Whether microglia are protective or pathologic is context dependent; the outcome varies as a function of time relative to the stimulus, activation state of neighboring cells in the microenvironment or within progression of a particular disease. Although brain microglia can be "primed" using bacterial lipopolysaccharide (LPS)/endotoxin, it is unknown whether LPS delivered systemically can also induce neuroprotective microglia in the spinal cord. Here, we show that serial systemic injections of LPS (1 mg/kg, i.p., daily) for 4 consecutive days (LPSx4) consistently elicit a reactive spinal cord microglia response marked by dramatic morphologic changes, increased production of IL-1, and enhanced proliferation without triggering leukocyte recruitment or overt neuropathology. Following LPSx4, reactive microglia frequently contact spinal cord endothelial cells. Targeted ablation or selective expression of IL-1 and IL-1 receptor (IL-1R) in either microglia or endothelia reveal that IL-1-dependent signaling between these cells mediates microglia activation. Using a mouse model of ischemic spinal cord injury in male and female mice, we show that preoperative LPSx4 provides complete protection from ischemia-induced neuron loss and hindlimb paralysis. Neuroprotection is partly reversed by either pharmacological elimination of microglia or selective removal of IL-1R in microglia or endothelia. These data indicate that spinal cord microglia are amenable to therapeutic reprogramming via systemic manipulation and that this potential can be harnessed to protect the spinal cord from injury.SIGNIFICANCE STATEMENT Data in this report indicate that a neuroprotective spinal cord microglia response can be triggered by daily systemic injections of LPS over a period of 4 d (LPSx4). The LPSx4 regimen induces morphologic transformation and enhances proliferation of spinal cord microglia without causing neuropathology. Using advanced transgenic mouse technology, we show that IL-1-dependent microglia-endothelia cross talk is necessary for eliciting this spinal cord microglia phenotype and also for conferring optimal protection to spinal motor neurons from ischemic spinal cord injury (ISCI). Collectively, these novel data show that it is possible to consistently elicit spinal cord microglia via systemic delivery of inflammogens to achieve a therapeutically effective neuroprotective response against ISCI.
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Effect of Topical Administration of Somatostatin on Retinal Inflammation and Neurodegeneration in an Experimental Model of Diabetes. J Clin Med 2020; 9:jcm9082579. [PMID: 32784955 PMCID: PMC7463891 DOI: 10.3390/jcm9082579] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/25/2020] [Accepted: 08/04/2020] [Indexed: 12/11/2022] Open
Abstract
Somatostatin (SST) is a neuroprotective peptide but little is known regarding the potential role of its anti-inflammatory effects on retinal neuroprotection. In a previous study, we provided the first evidence that topical (eye drops) administration of SST prevents retinal neurodegeneration in streptozotocin (STZ)-induced diabetic rats. However, STZ by itself could cause neurotoxicity, thus acting as a confounding factor. The aims of the present study were: (1) to test the effect of topical administration of SST in the db/db mouse model, a spontaneous model of type 2 diabetes, thus avoiding the confounding effect of STZ on neurodegeneration; (2) to further explore the anti-inflammatory mechanisms of SST in glial cells. This task was performed by using mouse retinal explants and cell cultures. In summary, we confirm that SST topically administered was able to prevent retinal neurodysfunction and neurodegeneration in db/db mice. Furthermore, we found that SST prevented the activation of the classical M1 response of Bv.2 microglial cells upon Lipopolysaccharide (LPS) stimulation as a potent pro-inflammatory trigger. The anti-inflammatory effect of SST in Bv.2 cells was also observed in response to hypoxia. In conclusion, we provide evidence that the neuroprotective effect of SST in diabetic retinas can be largely attributed to anti-inflammatory mechanisms.
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Su XQ, Wang XY, Gong FT, Feng M, Bai JJ, Zhang RR, Dang XQ. Oral treatment with glycyrrhizin inhibits NLRP3 inflammasome activation and promotes microglial M2 polarization after traumatic spinal cord injury. Brain Res Bull 2020; 158:1-8. [DOI: 10.1016/j.brainresbull.2020.02.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Revised: 01/19/2020] [Accepted: 02/20/2020] [Indexed: 12/11/2022]
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21
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Shao G, Zhou C, Ma K, Zhao W, Xiong Q, Yang L, Huang Z, Yang Z. MiRNA-494 enhances M1 macrophage polarization via Nrdp1 in ICH mice model. JOURNAL OF INFLAMMATION-LONDON 2020; 17:17. [PMID: 32351331 PMCID: PMC7183644 DOI: 10.1186/s12950-020-00247-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 04/08/2020] [Indexed: 12/19/2022]
Abstract
Background Ubiquitination-mediated M1/M2 macrophage polarization plays important roles in the pathogenesis of immune disease. However, the regulatory mechanism of ubiquitination during M1/M2 macrophage polarization following intracerebral hemorrhage (ICH) has not been well studied. Methods In the experiment, macrophages were administered with erythrocyte lysates, and then miR-494-, Nrdp1-, and M1/M2-related markers were analyzed. Brain inflammatory response, brain edema, and neurological functions of ICH mice were also assessed. Results We found that miR-494 levels increased while Nrdp1 levels decreased in macrophages after ICH. We also demonstrated that miR-494 inhibited Nrdp1 expression by directly binding its 3′-untranslated region. MiR-494 attenuated C/EBP-β activation and downstream proinflammatory factor production. Upregulation of Nrdp1 in macrophages significantly promoted M2 macrophage polarization via ubiquitinating and activating C/EBP-β. Moreover, the results indicated that miR-494 could enhance M1 macrophage polarization, promote brain edema, and impair neurological functions in ICH mice. Conclusions Taken together, our results demonstrated that Nrdp1 contributed to M1/M2 macrophage polarization and neuroinflammation via ubiquitination and activation of C/EBP-β in ICH. miR-494 may provide a promising therapeutic clue for ICH.
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Affiliation(s)
- Gaohai Shao
- 1Department of orthopedics, Yongchuan Hospital, Chongqing Medical University, Chongqing, 402160 China
| | - Changlong Zhou
- 2Department of Neurology and Chongqing key laboratory of cerebravascular disease, Yongchuan Hospital, Chongqing Medical University, Chongqing, 402160 China
| | - Kunlong Ma
- 1Department of orthopedics, Yongchuan Hospital, Chongqing Medical University, Chongqing, 402160 China
| | - Wang Zhao
- 2Department of Neurology and Chongqing key laboratory of cerebravascular disease, Yongchuan Hospital, Chongqing Medical University, Chongqing, 402160 China
| | - Qijiang Xiong
- 2Department of Neurology and Chongqing key laboratory of cerebravascular disease, Yongchuan Hospital, Chongqing Medical University, Chongqing, 402160 China
| | - Ling Yang
- 2Department of Neurology and Chongqing key laboratory of cerebravascular disease, Yongchuan Hospital, Chongqing Medical University, Chongqing, 402160 China
| | - Zhongyan Huang
- 2Department of Neurology and Chongqing key laboratory of cerebravascular disease, Yongchuan Hospital, Chongqing Medical University, Chongqing, 402160 China
| | - Zhao Yang
- 2Department of Neurology and Chongqing key laboratory of cerebravascular disease, Yongchuan Hospital, Chongqing Medical University, Chongqing, 402160 China
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Increased Neuroprotective Microglia and Photoreceptor Survival in the Retina from a Peptide Inhibitor of Myeloid Differentiation Factor 88 (MyD88). J Mol Neurosci 2020; 70:968-980. [PMID: 32072483 DOI: 10.1007/s12031-020-01503-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 02/05/2020] [Indexed: 01/14/2023]
Abstract
Myeloid differentiation factor 88 (MyD88) is an adaptor protein for the Toll-like receptor (TLR) and interleukin 1 receptor (IL-1R) families of innate immunity receptors that mediate inflammatory responses to cellular injury. TLR/IL1R/MyD88 signaling is known to contribute to retinal degeneration, although how MyD88 regulates neuronal survival, and the effect of MyD88 on the inflammatory environment in the retina, is mostly unknown. In this study, we tested the hypothesis that blocking MyD88-mediated signaling early in retinal degeneration promotes transition of microglia towards a neuroprotective anti-inflammatory phenotype, resulting in enhanced photoreceptor survival. We also tested whether systemic delivery of a pharmacologic MyD88 inhibitor has therapeutic potential. The rd10 mouse model of retinal degeneration was injected intraperitoneally with increasing doses of a MyD88 blocking peptide or control peptide early in degeneration, and inflammatory responses and photoreceptor survival were measured at specific time points using flow cytometry, cytokine profiling, and electroretinograms. Our results demonstrated that rd10 mice injected with a low dose of MyD88 inhibitor peptide showed increased rod photoreceptor function and reduced apoptosis compared with control peptide and uninjected mice. MyD88 inhibition also resulted in fewer microglia/macrophage cells in the photoreceptor layer whereas total peripheral and retinal macrophage were not changed. Furthermore, increased number of cells expressing the Arg1 marker of neuroprotective microglia in the photoreceptor layer and higher MCP-1 and anti-inflammatory cytokine IL-27 were associated with photoreceptor survival. Therefore, these data suggest that the MyD88 inhibitor modified the retina environment to become less inflammatory, leading to improved photoreceptor function and survival.
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23
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Eslami M, Alizadeh L, Morteza-Zadeh P, Sayyah M. The effect of Lipopolysaccharide (LPS) pretreatment on hippocampal apoptosis in traumatic rats. Neurol Res 2020; 42:91-98. [PMID: 31914902 DOI: 10.1080/01616412.2019.1709139] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Objectives: Traumatic brain injury (TBI) is a serious medical problem that affects the quality of life. Apoptosis is a form of programmed cell death that happens after trauma. Effector caspases are responsible for initiating apoptosis.Methods: In the present study, we examined the effect of LPS preconditioning (0.1 and 0.5 mg/kg, ip; 5 days prior controlled cortical injury) on apoptosis, 4 and 12 hours after trauma. We investigated possible mechanisms on the expression of caspase3 and caspase7 in hippocampal CA1 and CA3 areas by using immunohistochemistry and Western blotting techniques and also TUNEL-positive cells.Results: Higher expression of caspase3 and caspase7 were accompanied by a higher number of dead neurons in traumatic rats 4 and 12 hours after trauma(P < 0.05). LPS preconditioning decreased caspase3 and caspase7over-expression and the number of dead neurons in the hippocampus(P < 0.05).Discussion: Our data indicate that LPS preconditioning inhibits neural damage and apoptosis induced by trauma in the hippocampus.
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Affiliation(s)
- Mansoureh Eslami
- Department of Basic Sciences, School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Leila Alizadeh
- Shefa Neuroscience Research Center, Khatam Alanbia Hospital, Tehran, Iran
| | | | - Mohammad Sayyah
- Department of Physiology and Pharmacology, Pasteur Institute of Iran, Tehran, Iran
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24
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Akhmetzyanova E, Kletenkov K, Mukhamedshina Y, Rizvanov A. Different Approaches to Modulation of Microglia Phenotypes After Spinal Cord Injury. Front Syst Neurosci 2019; 13:37. [PMID: 31507384 PMCID: PMC6718713 DOI: 10.3389/fnsys.2019.00037] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Accepted: 07/29/2019] [Indexed: 01/04/2023] Open
Abstract
Microglial cells, which are highly plastic, immediately respond to any change in the microenvironment by becoming activated and shifting the phenotype toward neurotoxicity or neuroprotection. The polarization of microglia/macrophages after spinal cord injury (SCI) seems to be a dynamic process and can change depending on the microenvironment, stage, course, and severity of the posttraumatic process. Effective methods to modulate microglia toward a neuroprotective phenotype in order to stimulate neuroregeneration are actively sought for. In this context, available approaches that can selectively impact the polarization of microglia/macrophages regulate synthesis of trophic factors and cytokines/chemokines in them, and their phagocytic function and effects on the course and outcome of SCI are discussed in this review.
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Affiliation(s)
- Elvira Akhmetzyanova
- OpenLab Gene and Cell Technologies, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
| | - Konstantin Kletenkov
- OpenLab Gene and Cell Technologies, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
| | - Yana Mukhamedshina
- OpenLab Gene and Cell Technologies, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia.,Department of Histology, Cytology and Embryology, Kazan State Medical University, Kazan, Russia
| | - Albert Rizvanov
- OpenLab Gene and Cell Technologies, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
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25
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Hermann JK, Capadona JR. Understanding the Role of Innate Immunity in the Response to Intracortical Microelectrodes. Crit Rev Biomed Eng 2019; 46:341-367. [PMID: 30806249 DOI: 10.1615/critrevbiomedeng.2018027166] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Intracortical microelectrodes exhibit enormous potential for researching the nervous system, steering assistive devices and functional electrode stimulation systems for severely paralyzed individuals, and augmenting the brain with computing power. Unfortunately, intracortical microelectrodes often fail to consistently record signals over clinically useful periods. Biological mechanisms, such as the foreign body response to intracortical microelectrodes and self-perpetuating neuroinflammatory cascades, contribute to the inconsistencies and decline in recording performance. Unfortunately, few studies have directly correlated microelectrode performance with the neuroinflammatory response to the implanted devices. However, of those select studies that have, the role of the innate immune system remains among the most likely links capable of corroborating the results of different studies, across laboratories. Therefore, the overall goal of this review is to highlight the role of innate immunity signaling in the foreign body response to intracortical microelectrodes and hypothesize as to appropriate strategies that may become the most relevant in enabling brain-dwelling electrodes of any geometry, or location, for a range of clinical applications.
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Affiliation(s)
- John K Hermann
- Department of Biomedical Engineering, Case Western Reserve University, 2071 Martin Luther King Jr. Drive, Wickenden Bldg, Cleveland, OH 44106; Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland VA Medical Center, 10701 East Blvd. Mail Stop 151 AW/APT, Cleveland, OH 44106-1702
| | - Jeffrey R Capadona
- Department of Biomedical Engineering, Case Western Reserve University, 2071 Martin Luther King Jr. Drive, Wickenden Bldg, Cleveland, OH 44106; Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland VA Medical Center, 10701 East Blvd. Mail Stop 151 AW/APT, Cleveland, OH 44106-1702
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Observational study of long-term persistent elevation of neurodegeneration markers after cardiac surgery. Sci Rep 2019; 9:7177. [PMID: 31073130 PMCID: PMC6509119 DOI: 10.1038/s41598-019-42351-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 03/11/2019] [Indexed: 12/17/2022] Open
Abstract
Surgery and anesthesia induce inflammatory changes in the central nervous system, which ultimately lead to neuronal damage concomitant with an increase in the level of neurodegeneration markers. Despite some experimental data showing prolonged activation of the immune system post-surgery, no study has determined the extent of long-term elevation of neurodegeneration markers. The purpose of this study was to investigate the serum levels of tau protein, ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1), neurofilament light (NF-L), and glial fibrillary acidic protein (GFAP) after elective cardiac surgery with the implementation of cardiopulmonary bypass (CPB). The serum levels of these markers from 30 patients were compared longitudinally to the baseline (pre-surgery or t0), at 24 hours (t+24), at 7 days (t+7d), and at 3 months (t+3m). The secondary outcome was the production of macrophage-colony stimulating factor (M-CSF) and tumor necrosis factor-α (TNF-α) in vitro by isolated monocytes in response to lipopolysaccharide (LPS) as the measure of immune system activation. The tertiary outcome was the serum level of C-reactive protein (CRP), serum amyloid P (SAP), and α-2-macroglobulin (A2M). Serum levels of tau protein increased 24 hours after surgery (p = 0.0015) and remained elevated at 7 days (p = 0.0017) and three months (p = 0.036). Serum levels of UCH-L1 peaked at 24 hours (p = 0.00055) and normalized at 3 months. In vitro secretion of M-CSF by LPS-stimulated peripheral monocytes, but not TNFα, correlated highly (r = 0.58; p = 0.04) with persistent elevation of serum tau levels at 3 months. The serum CRP and SAP increases correlated with tau post-CPB levels significantly at 3 months. We demonstrated that elevation of serum tau levels at 24 hours, 7 days, and 3 months after heart surgery is concomitant with some traits of inflammation after CPB. The elevation of tau several weeks into recovery is significantly longer than expected.
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Parenchymal and non-parenchymal immune cells in the brain: A critical role in regulating CNS functions. Int J Dev Neurosci 2019; 77:26-38. [PMID: 31026497 DOI: 10.1016/j.ijdevneu.2019.04.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 03/18/2019] [Accepted: 04/19/2019] [Indexed: 12/12/2022] Open
Abstract
The presence of immune cells in the central nervous system has long been the subject of research to find out their role. For a long time it was believed that the CNS was a privileged area from an immunological point of view, due to the presence of the blood-brain barrier (BBB), as circulating immune cells were unable to penetrate the brain parenchyma, at least until the integrity of the BBB was preserved. For this reason the study of the CNS immune system has focused on the functions of microglia, the immunocompetent resident element of the brain parenchyma that retain the ability to divide and self-renew during lifespan without any significant contribution from circulating blood cells. More recently, the presence of lymphatic vessels in the dural sinuses has been demonstrated with accompanying lymphocytes, monocytes and other immune cells. Moreover, meningeal macrophages, that is macrophages along the blood vessels and in the choroid plexus (CP), are also present. These non-parenchymal immune cells, together with microglia, can affect multiple CNS functions. Here, we discuss the functional role of parenchymal and non-parenchymal immune cells and their contribution to the regulation of neurogenesis.
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28
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Chen L, Gao B, Zhang Y, Lu H, Li X, Pan L, Yin L, Zhi X. PAR2 promotes M1 macrophage polarization and inflammation via FOXO1 pathway. J Cell Biochem 2018; 120:9799-9809. [PMID: 30552714 DOI: 10.1002/jcb.28260] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 10/24/2018] [Indexed: 12/17/2022]
Abstract
Macrophages polarization plays essential but different roles in most diseases such as atherosclerosis, adipose tissue inflammation, and insulin resistance. Our previous study revealed that protease-activated receptor 2 (PAR2), a G-protein coupled receptor influenced macrophage function, but little is known regarding the regulation of macrophage polarization process and its potential mechanisms. In the present study, bone marrow-derived macrophages (BMDM) isolated from C57/BL6 mice and cultured with L929-conditional medium and murine macrophage cell line RAW264.7 were used to study the function of PAR2 activation in vitro. BMDM was stimulated by the small molecular PAR2 agonist, 2-furoyl-LIGRLO-amide trifluoroacetate salt, followed by transcription factor microarray to screen the significantly activated signaling pathways under PAR2 activation. Western blot analysis, quantitative real-time polymerase chain reaction (qRT-PCR) was used to evaluate the expression of targeted genes and transcription factors. Immunofluorescence was used to observe the subcellular distribution of transcription factors. Our results demonstrated that M1-like polarization was presented by PAR2 agonist treatment with significant upregulation of interleukin-1β, interleukin-6, monocyte chemotactic protein-1, and tumor necrosis factor-α in BMDM and RAW264.7. Microarray identified forkhead box protein O1 (FOXO1) was significantly increased under PAR2 agonist stimulation, which was confirmed by qPCR and Western blot analysis. Immunofluorescence demonstrated that increased FOXO1 accumulated in the nucleus, which is necessary to promote transcription for targeted genes. We further knocked down FOXO1 expression using small interfering RNA, which alleviated PAR2-induced proinflammatory gene expression. The PAR2/FOXO1 pathway mediated stimulation of proinflammatory genes was further confirmed by tryptase, an endogenous ligand of PAR2. In conclusion, this study demonstrated that PAR2 activation-induced M1 polarization and inflammation through the FOXO1-dependent pathway.
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Affiliation(s)
- Liang Chen
- Department of Physiology & Pathophysiology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China.,State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Beiyao Gao
- Department of Rehabilitation, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yadong Zhang
- Laboratory of Medical Molecular Biology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Hanyu Lu
- Department of Physiology & Pathophysiology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China
| | - Xiaobo Li
- Department of Physiology & Pathophysiology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China
| | - Luanfeng Pan
- Laboratory of Medical Molecular Biology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Lianhua Yin
- Department of Physiology & Pathophysiology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China
| | - Xiuling Zhi
- Department of Physiology & Pathophysiology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China
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Hersh J, Yang SH. Glia-immune interactions post-ischemic stroke and potential therapies. Exp Biol Med (Maywood) 2018; 243:1302-1312. [PMID: 30537868 DOI: 10.1177/1535370218818172] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
IMPACT STATEMENT This article reviews glial cell interactions with the immune system post-ischemic stroke. Research has shown that glial cells in the brain play a role in altering phenotypes of other glial cells and have downstream immune cell targets ultimately regulating a neuroinflammatory response. These interactions may play a deleterious as well as beneficial role in stroke recovery. Furthermore, they may provide a novel way to approach potential therapies, since current stroke drug therapy is limited to only one Food and Drug Administration-approved drug complicated by a narrow therapeutic window. Until this point, most research has emphasized neuroimmune interactions, but little focus has been on bidirectional communication of glial-immune interactions in the ischemic brain. By expanding our understanding of these interactions through a compilation of glial cell effects, we may be able to pinpoint major modulating factors in brain homeostasis to maintain or discover ways to suppress irreversible ischemic damage and improve brain repair.
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Affiliation(s)
- Jessica Hersh
- Department of Neuroscience and Pharmacology, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
| | - Shao-Hua Yang
- Department of Neuroscience and Pharmacology, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
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30
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Calabrese EJ, Giordano JJ, Kozumbo WJ, Leak RK, Bhatia TN. Hormesis mediates dose-sensitive shifts in macrophage activation patterns. Pharmacol Res 2018; 137:236-249. [DOI: 10.1016/j.phrs.2018.10.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 10/09/2018] [Accepted: 10/09/2018] [Indexed: 02/07/2023]
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31
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Farrag M, Leipzig ND. Subcutaneous Maturation of Neural Stem Cell-Loaded Hydrogels Forms Region-Specific Neuroepithelium. Cells 2018; 7:cells7100173. [PMID: 30336590 PMCID: PMC6210402 DOI: 10.3390/cells7100173] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 10/09/2018] [Accepted: 10/11/2018] [Indexed: 01/14/2023] Open
Abstract
A combinatorial approach integrating stem cells and capable of exploiting available cues is likely needed to regenerate lost neural tissues and ultimately restore neurologic functions. This study investigates the effects of the subcutaneous maturation of adult-derived neural stem cell (aNSCs) seeded into biomaterial constructs on aNSC differentiation and ultimate regional neuronal identity as a first step toward a future spinal cord injury treatment. To achieve this, we encapsulated rat aNSCs in chitosan-based hydrogels functionalized with immobilized azide-tagged interferon-γ inside a chitosan conduit. Then, we implanted these constructs in the subcutaneous tissues in the backs of rats in the cervical, thoracic, and lumbar regions for 4, 6, and 8 weeks. After harvesting the scaffolds, we analyzed cell differentiation qualitatively using immunohistochemical analysis and quantitatively using RT-qPCR. Results revealed that the hydrogels supported aNSC survival and differentiation up to 4 weeks in the subcutaneous environment as marked by the expression of several neurogenesis markers. Most interesting, the aNSCs expressed region-specific Hox genes corresponding to their region of implantation. This study lays the groundwork for further translational work to recapitulate the potentially undiscovered patterning cues in the subcutaneous tissue and provide support for the conceptual premise that our bioengineering approach can form caudalized region-specific neuroepithelium.
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Affiliation(s)
- Mahmoud Farrag
- Integrated Bioscience Program, The University of Akron, Akron, OH 44325, USA.
| | - Nic D Leipzig
- Integrated Bioscience Program, The University of Akron, Akron, OH 44325, USA.
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325, USA.
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AC-YVAD-CMK Inhibits Pyroptosis and Improves Functional Outcome after Intracerebral Hemorrhage. BIOMED RESEARCH INTERNATIONAL 2018; 2018:3706047. [PMID: 30410928 PMCID: PMC6206581 DOI: 10.1155/2018/3706047] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 08/25/2018] [Accepted: 09/17/2018] [Indexed: 01/06/2023]
Abstract
Intracerebral hemorrhage (ICH) refers to bleeding in the brain and is associated with the release of large amount of inflammasomes, and the activation of different cell death pathways. These cell death pathways lead to removal of inactivated and damaged cells and also result in neuronal cell damage. Pyroptosis is a newly discovered cell death pathway that has gained attention in recent years. This pathway mainly depends on activation of caspase-1-mediated cascades to cause cell death. We tested a well-known selective inhibitor of caspase-1, AC-YVAD-CMK, which has previously been found to have neuroprotective effects in ICH mice model, to ascertain its effects on the activation of inflammasomes mediated pyroptosis. Our results showed that AC-YVAD-CMK could reduce caspase-1 activation and inhibit IL-1β production and maturation, but has no effect on NLRP3 expression, an upstream inflammatory complex. AC-YVAD-CMK administration also resulted in reduction in M1-type microglia polarization around the hematoma, while increasing the number of M2-type cells. Furthermore, AC-YVAD-CMK treated mice showed some recovery of neurological function after hemorrhage especially at the hyperacute and subacute stage resulting in some degree of limb movement. In conclusion, we are of the view that AC-YVAD-CMK could inhibit pyroptosis, decrease the secretion or activation of inflammatory factors, and affect the polarization of microglia resulting in improvement of neurological function after ICH.
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33
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Zhang L, Zhang J, You Z. Switching of the Microglial Activation Phenotype Is a Possible Treatment for Depression Disorder. Front Cell Neurosci 2018; 12:306. [PMID: 30459555 PMCID: PMC6232769 DOI: 10.3389/fncel.2018.00306] [Citation(s) in RCA: 188] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 08/22/2018] [Indexed: 12/16/2022] Open
Abstract
Major depressive disorder (MDD) is a common emotional cognitive disorder that seriously affects people’s physical and mental health and their quality of life. Due to its clinical and etiological heterogeneity, the molecular mechanisms underpinning MDD are complex and they are not fully understood. In addition, the effects of traditional drug therapy are not ideal. However, postmortem and animal studies have shown that overactivated microglia can inhibit neurogenesis in the hippocampus and induce depressive-like behaviors. Nonetheless, the molecular mechanisms by which microglia regulate nerve regeneration and determine depressive-like behaviors remain unclear. As the immune cells of the central nervous system (CNS), microglia could influence neurogenesis through the M1 and M2 subtypes, and these may promote depressive-like behaviors. Microglia may be divided into four main states or phenotypes. Under stress, microglial cells are induced into the M1 type, releasing inflammatory factors and causing neuroinflammatory responses. After the inflammation fades away, microglia shift into the alternative activated M2 phenotypes that play a role in neuroprotection. These activated M2 subtypes consist of M2a, M2b and M2c and their functions are different in the CNS. In this article, we mainly introduce the relationship between microglia and MDD. Importantly, this article elucidates a plausible mechanism by which microglia regulate inflammation and neurogenesis in ameliorating MDD. This could provide a reliable basis for the treatment of MDD in the future.
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Affiliation(s)
- Lijuan Zhang
- Center for Informational Biology, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Jinqiang Zhang
- Center for Informational Biology, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Zili You
- Center for Informational Biology, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
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34
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Liu JT, Wu SX, Zhang H, Kuang F. Inhibition of MyD88 Signaling Skews Microglia/Macrophage Polarization and Attenuates Neuronal Apoptosis in the Hippocampus After Status Epilepticus in Mice. Neurotherapeutics 2018; 15:1093-1111. [PMID: 30112701 PMCID: PMC6277303 DOI: 10.1007/s13311-018-0653-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Inflammation is implicated in epileptogenesis. Activated microglia and macrophages (MG/MΦ) are found in the brains of patients with epilepsy-related diseases and animal models of epilepsy. It is not yet known how the MG/MΦ activation phenotype affects pathological changes in the brain after a single seizure. In this study, we had 2 main purposes: first, to characterize post-status epilepticus (SE) inflammation by tracking MG/MΦ polarization, and, second, to explore the role of an innate immune receptor adaptor protein, namely, myeloid differentiation primary response gene 88 (MyD88), in the induction of SE in a mouse model. A lithium-pilocarpine model of seizure conditions was generated in C57BL/6 mice. The intensity and distribution of MG/MΦ polarization were tracked by fluorescent immunohistochemistry and Western blotting for the polarization markers inducible nitrogen oxygenized synthase, arginase-1, CD163, and mannose receptor. We observed steadily increasing M1 MG/MΦ along with MyD88 signal upregulation after SE in the hippocampi of mice, whereas the M2 marker arginase-1 was localized mainly in astrocytes rather than in MG/MΦ. Inhibition or gene knockout of MyD88 reduced M1 MG/MΦ and gliosis although increasing M2 MG/MΦ in the hippocampi of SE mice. MyD88 inhibition also augmented glutamate transporter 1 expression and reduced N-methyl-D-aspartate receptor NR1 subunit expression in the hippocampus to protect pyramidal neurons from apoptosis. These data suggest that MG/MΦ polarization after SE impacts the pathological outcome of the hippocampus via MyD88 signaling and point to MyD88 as a potential neuroprotective target for epilepsy therapy.
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Affiliation(s)
- Jin-Tao Liu
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, No. 569 Xinsi Road, Xi'an, 710038, China
- Institute of Neurosciences, Department of Neurobiology and Collaborative Innovation Center for Brain Science, The Fourth Military Medical University, No. 169, Changle West Road, Xi'an, 710032, China
- Department of Orthopedics, The 413th Hospital of the Chinese People's Liberation Army, Zhoushan, 316000, China
| | - Sheng-Xi Wu
- Institute of Neurosciences, Department of Neurobiology and Collaborative Innovation Center for Brain Science, The Fourth Military Medical University, No. 169, Changle West Road, Xi'an, 710032, China
| | - Hua Zhang
- Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, No. 569 Xinsi Road, Xi'an, 710038, China.
| | - Fang Kuang
- Institute of Neurosciences, Department of Neurobiology and Collaborative Innovation Center for Brain Science, The Fourth Military Medical University, No. 169, Changle West Road, Xi'an, 710032, China.
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35
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Calabrese V, Santoro A, Trovato Salinaro A, Modafferi S, Scuto M, Albouchi F, Monti D, Giordano J, Zappia M, Franceschi C, Calabrese EJ. Hormetic approaches to the treatment of Parkinson's disease: Perspectives and possibilities. J Neurosci Res 2018; 96:1641-1662. [PMID: 30098077 DOI: 10.1002/jnr.24244] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2017] [Revised: 03/21/2018] [Accepted: 03/21/2018] [Indexed: 01/17/2023]
Abstract
Age-related changes in the brain reflect a dynamic interaction of genetic, epigenetic, phenotypic, and environmental factors that can be temporally restricted or more longitudinally present throughout the lifespan. Fundamental to these mechanisms is the capacity for physiological adaptation through modulation of diverse molecular and biochemical signaling occurring from the intracellular to the network-systemic level throughout the brain. A number of agents that affect the onset and progression of Parkinson's disease (PD)-like effects in experimental models exhibit temporal features, and mechanisms of hormetic dose responses. These findings have particular significance since the hormetic dose response describes the amplitude and range of potential therapeutic effects, thereby affecting the design and conduct of studies of interventions against PD (and other neurodegenerative diseases), and may also be important to a broader consideration of hormetic processes in resilient adaptive responses that might afford protection against the onset and/or progression of PD and related disorders.
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Affiliation(s)
- Vittorio Calabrese
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, Catania.,IBREGENS, Nutraceuticals and Functional Food Biotechnologies Research Associated, University of Catania, Italy
| | - Aurelia Santoro
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, Italy
| | - Angela Trovato Salinaro
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, Catania
| | - Sergio Modafferi
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, Catania
| | - Maria Scuto
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, Catania
| | - Ferdaous Albouchi
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, Catania
| | - Daniela Monti
- Department of Experimental, Clinical and Biomedical Sciences "Mario Serio", University of Florence, Florence, Italy
| | - James Giordano
- Departments of Neurology and Biochemistry, and Neuroethics Studies Program, Georgetown University Medical Center, Washington, District of Columbia, USA
| | - Mario Zappia
- Department of Medical Sciences, Surgical and Advanced Technologies G.F. Ingrassia, Section of Neurosciences, University of Catania, Italy
| | | | - Edward J Calabrese
- Environmental Health Sciences Division, School of Public Health, University of Massachusetts, Amherst, Massachusetts, USA
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36
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Noristani HN, They L, Perrin FE. C57BL/6 and Swiss Webster Mice Display Differences in Mobility, Gliosis, Microcavity Formation and Lesion Volume After Severe Spinal Cord Injury. Front Cell Neurosci 2018; 12:173. [PMID: 29977191 PMCID: PMC6021489 DOI: 10.3389/fncel.2018.00173] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 06/01/2018] [Indexed: 12/20/2022] Open
Abstract
Spinal cord injuries (SCI) are neuropathologies causing enormous physical and emotional anguish as well as irreversibly disabilities with great socio/economic burdens to our society. The availability of multiple mouse strains is important for studying the underlying pathophysiological response after SCI. Although strain differences have been shown to directly affect spontaneous functional recovery following incomplete SCI, its influence after complete lesion of the spinal cord is unclear. To study the influence of mouse strain on recovery after severe SCI, we first carried out behavioral analyses up to 6 weeks following complete transection of the spinal cord in mice with two different genetic backgrounds namely, C57BL/6 and Swiss Webster. Using immunohistochemistry, we then analyzed glial cell reactivity not only at different time-points after injury but also at different distances from the lesion epicenter. Behavioral assessments using CatWalk™ and open field analyses revealed increased mobility (measured using average speed) and differential forelimb gross sensory response in Swiss Webster compared to C57BL/6 mice after complete transection of the spinal cord. Comprehensive histological assessment revealed elevated microglia/macrophage reactivity and a moderate increase in astrogliosis in Swiss Webster that was associated with reduced microcavity formation and reduced lesion volume after spinal cord transection compared to C57BL/6 mice. Our results thus suggest that increased mobility correlates with enhanced gliosis and better tissue protection after complete transection of the spinal cord.
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Affiliation(s)
- Harun Najib Noristani
- INSERM U1198, University of Montpellier, EPHE, Montpellier, France.,INSERM U1051, Montpellier, France
| | | | - Florence Evelyne Perrin
- INSERM U1198, University of Montpellier, EPHE, Montpellier, France.,INSERM U1051, Montpellier, France
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37
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Guo J, Wang H, Li L, Yuan Y, Shi X, Hou S. Treatment with IL-19 improves locomotor functional recovery after contusion trauma to the spinal cord. Br J Pharmacol 2018; 175:2611-2621. [PMID: 29500933 DOI: 10.1111/bph.14193] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 02/07/2018] [Accepted: 02/08/2018] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND AND PURPOSE IL-19 skews the immune response towards a Th2 type and appears to stimulate angiogenesis. In the current study, we tested if IL-19 treatment could reduce secondary injury and improve functional recovery after contusion spinal cord injury (SCI). EXPERIMENTAL APPROACH Firstly, mice were given a moderate-severe thoracic SCI at the T9-10 level and expression of IL-19 and its receptor was measured in the injured spinal cord. Then SCI mice were treated with mouse recombinant IL-19 and its blocking antibody to investigate the therapeutic effect of IL-19. KEY RESULTS Protein expression of IL-19 and its receptor IL-20R1 and IL-20R2 was up-regulated in the injured spinal cord of mice. IL-19 treatment promoted the recovery of locomotor function dose-dependently and reduced loss of motor neurons and microglial and glial activation following SCI. Treatment of SCI mice with IL-19 attenuated macrophage accumulation, reduced protein levels of TNF-α and CCL2 and promoted Th2 response and M2 macrophage activation in the injured region. Treatment of SCI mice with IL-19 promoted angiogenesis through up-regulating VEGF in the injured region. Treatment of SCI mice with IL-19 up-regulated HO-1 expression and decreased oxidative stress in the injured region. The beneficial effect of IL-19 was abolished by coadministration of the blocking antibody. Additionally, IL-19 deficiency in mice delayed the recovery of locomotor function following SCI. CONCLUSIONS AND IMPLICATIONS IL-19 treatment reduced secondary injuries and improved locomotor functional recovery after contusion SCI, through diverse mechanisms including immune cell polarization, angiogenesis and anti-oxidative responses.
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Affiliation(s)
- Jidong Guo
- Institute of Orthopaedics, First Affiliated Hospital of CPLA General Hospital, Beijing, China
| | - Huadong Wang
- Institute of Orthopaedics, First Affiliated Hospital of CPLA General Hospital, Beijing, China
| | - Li Li
- Institute of Orthopaedics, First Affiliated Hospital of CPLA General Hospital, Beijing, China
| | - Yanli Yuan
- Institute of Orthopaedics, First Affiliated Hospital of CPLA General Hospital, Beijing, China
| | - Xiuxiu Shi
- Institute of Orthopaedics, First Affiliated Hospital of CPLA General Hospital, Beijing, China
| | - Shuxun Hou
- Institute of Orthopaedics, First Affiliated Hospital of CPLA General Hospital, Beijing, China
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38
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Jo MJ, Kumar H, Joshi HP, Choi H, Ko WK, Kim JM, Hwang SSS, Park SY, Sohn S, Bello AB, Kim KT, Lee SH, Zeng X, Han I. Oral Administration of α-Asarone Promotes Functional Recovery in Rats With Spinal Cord Injury. Front Pharmacol 2018; 9:445. [PMID: 29867457 PMCID: PMC5949368 DOI: 10.3389/fphar.2018.00445] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 04/17/2018] [Indexed: 11/13/2022] Open
Abstract
α-asarone, a bioactive compound found in Acorus plant species, has been shown to exhibit neuroprotective, anti-oxidative, anti-inflammatory, and cognitive-enhancing effects. However, the effects of α-asarone on spinal cord injury (SCI) have not yet been elucidated. The present study investigated the effects of α-asarone on the mRNA of pro-inflammatory cytokines, macrophage polarization toward an anti-inflammatory M2 phenotype, and angiogenesis in rats with compressive SCI. α-Asarone was orally administered (10 mg/kg) once per day for 14 days following moderate static compression SCI. Compared to controls, α-asarone treatment significantly improved locomotor score, prevented neuroinflammation, and facilitated angiogenesis in the spinal cord at 14 days after SCI. Furthermore, α-asarone significantly reduced the TNF-α, IL-1β, IL-6, monocyte chemoattractant protein 1 (MCP-1), macrophage inflammatory protein 2 (MIP-2), and inducible nitric oxide synthase (iNOS) levels but increased the IL-4, IL-10, and arginase 1 levels at 24 h after SCI. At 7 and 14 days after SCI, immunohistochemistry showed reduced reactive gliosis and neuroinflammation and an increased expression of M2 macrophage markers and angiogenesis. The results suggest that the inhibition of pro-inflammatory cytokines, macrophage polarization toward an anti-inflammatory M2 phenotype, and angiogenesis by α-asarone may be some of the mechanisms underlying the α-asarone-mediated neuroprotective effects on an injured spinal cord.
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Affiliation(s)
- Min-Jae Jo
- Department of Neurosurgery, CHA Bundang Medical Center, CHA University, Seongnam-si, South Korea
| | - Hemant Kumar
- Department of Neurosurgery, CHA Bundang Medical Center, CHA University, Seongnam-si, South Korea
| | - Hari P. Joshi
- Department of Neurosurgery, CHA Bundang Medical Center, CHA University, Seongnam-si, South Korea
| | - Hyemin Choi
- Department of Neurosurgery, CHA Bundang Medical Center, CHA University, Seongnam-si, South Korea
| | - Wan-Kyu Ko
- Department of Neurosurgery, CHA Bundang Medical Center, CHA University, Seongnam-si, South Korea
| | - J. M. Kim
- Department of Neurosurgery, CHA Bundang Medical Center, CHA University, Seongnam-si, South Korea
| | - Sean S. S. Hwang
- Department of Neurosurgery, CHA Bundang Medical Center, CHA University, Seongnam-si, South Korea
| | - Song Y. Park
- Department of Neurosurgery, CHA Bundang Medical Center, CHA University, Seongnam-si, South Korea
| | - Seil Sohn
- Department of Neurosurgery, CHA Bundang Medical Center, CHA University, Seongnam-si, South Korea
| | - Alvin B. Bello
- Department of Biomedical Science, CHA University, Seongnam-si, South Korea
| | - Kyoung-Tae Kim
- Department of Neurosurgery, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, South Korea
| | - Soo-Hong Lee
- Department of Biomedical Science, CHA University, Seongnam-si, South Korea
| | - Xiang Zeng
- Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Inbo Han
- Department of Neurosurgery, CHA Bundang Medical Center, CHA University, Seongnam-si, South Korea
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Bao LH, Zhang YN, Zhang JN, Gu L, Yang HM, Huang YY, Xia N, Zhang H. Urate inhibits microglia activation to protect neurons in an LPS-induced model of Parkinson's disease. J Neuroinflammation 2018; 15:131. [PMID: 29720230 PMCID: PMC5932803 DOI: 10.1186/s12974-018-1175-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 04/23/2018] [Indexed: 01/30/2023] Open
Abstract
Background Multiple risk factors contribute to the progression of Parkinson’s disease, including oxidative stress and neuroinflammation. Epidemiological studies have revealed a link between higher urate level and a lower risk of developing PD. However, the mechanistic basis for this association remains unclear. Urate protects dopaminergic neurons from cell death induced by oxidative stress. Here, we investigated a novel role of urate in microglia activation in a lipopolysaccharide (LPS)-induced PD model. Methods We utilized Griess, ELISA, real-time PCR, Western blot, immunohistochemistry, and immunofluorescence to detect the neuroinflammation. For Griess, ELISA, Western blot, and immunofluorescence assay, cells were seeded in 6-well plates pre-coated with poly-l-lysine (PLL) and incubated for 24 h with the indicated drugs. For real-time PCR assay, cells were seeded in 6-well plates pre-coated with PLL and incubated for 6 h with the indicated drugs. For animal experiments, rats were injected with urate or its vehicle twice daily for five consecutive days before and after stereotaxic surgery. Rats were killed and brain tissues were harvested after 4 weeks of LPS injection. Results In cultured BV2 cells and rat primary microglia, urate suppressed proinflammatory cytokine production and inducible cyclooxygenase 2 and nitric oxide synthase expression to protect dopaminergic neurons from the toxic effects of activated microglia. The neuroprotective effects of urate may also be associated with the stimulation of anti-inflammatory factors interleukin 10 and transforming growth factor β1. Intracellular urate level was increased in a dose-dependent manner upon co-treatment with urate and LPS as compared with LPS alone, an effect that was abrogated by pretreatment with probenecid (PBN), an inhibitor of both glucose transporter 9 and urate transporter 1 (URAT1). PBN also abolished the anti-inflammatory effect of urate. Consistent with these in vitro observations, the number of tyrosine hydroxylase-positive neurons was decreased and the loss of motor coordination was reversed by urate administration in an LPS-induced rat model of PD. Additionally, increased plasma urate level abolished the reduction of URAT1 expression, the increase in the expression of interleukin-1β, and the number of ionized calcium-binding adaptor molecule 1-positive microglia along with changes in their morphology. Conclusions Urate protects neurons against cytotoxicity induced by microglia activation via modulating urate transporter-mediated intracellular urate level. Electronic supplementary material The online version of this article (10.1186/s12974-018-1175-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Li-Hui Bao
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing, 100069, China
| | - Ya-Nan Zhang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing, 100069, China
| | - Jian-Nan Zhang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing, 100069, China
| | - Li Gu
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing, 100069, China
| | - Hui-Min Yang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing, 100069, China
| | - Yi-Ying Huang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing, 100069, China
| | - Ning Xia
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing, 100069, China
| | - Hong Zhang
- Department of Neurobiology, School of Basic Medical Sciences, Beijing Institute for Brain Disorders and Key Laboratory for Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing, 100069, China.
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Lee TM, Lin SZ, Chang NC. Nicorandil regulates the macrophage skewing and ameliorates myofibroblasts by inhibition of RhoA/Rho-kinase signalling in infarcted rats. J Cell Mol Med 2017; 22:1056-1069. [PMID: 29119680 PMCID: PMC5783972 DOI: 10.1111/jcmm.13130] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 01/17/2017] [Indexed: 01/06/2023] Open
Abstract
We have demonstrated that ATP-sensitive potassium (KATP ) channel agonists attenuated fibrosis; however, the mechanism remained unclear. Since RhoA has been identified as a mediator of cardiac fibrosis, we sought to determine whether the anti-fibrotic effects of KATP channel agonists were mediated via regulating macrophage phenotype and fibroblast differentiation by a RhoA/RhoA-kinase-dependent pathway. Wistar male rats after induction of myocardial infarction were randomized to either vehicle, nicorandil, an antagonist of KATP channel glibenclamide, an antagonist of ROCK fasudil, or a combination of nicorandil and glibenclamide or fasudil and glibenclamide starting 24 hrs after infarction. There were similar infarct sizes among the infarcted groups. At day 3 after infarction, post-infarction was associated with increased RhoA/ROCK activation, which can be inhibited by administering nicorandil. Nicorandil significantly increased myocardial IL-10 levels and the percentage of regulatory M2 macrophages assessed by immunohistochemical staining, Western blot, and RT-PCR compared with vehicle. An IL-10 receptor antibody increased myofibroblast infiltration compared with nicorandil alone. At day 28 after infarction, nicorandil was associated with attenuated cardiac fibrosis. These effects of nicorandil were functionally translated in improved echocardiographically derived cardiac performance. Fasudil showed similarly increased expression of M2 macrophages as nicorandil. The beneficial effects of nicorandil on fibroblast differentiation were blocked by adding glibenclamide. However, glibenclamide cannot abolish the attenuated fibrosis of fasudil, implying that RhoA/RhoA-kinase is a downstream effector of KATP channel activation. Nicorandil polarized macrophages into M2 phenotype by inhibiting RhoA/RhoA-kinase pathway, which leads to attenuated myofibroblast-induced cardiac fibrosis after myocardial infarction.
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Affiliation(s)
- Tsung-Ming Lee
- Cardiology Section, Department of Medicine, An-Nan Hospital, China Medical University, Tainan, Taiwan.,Department of Medicine, China Medical University, Taichung, Taiwan.,Cardiovascular Research Laboratory, China Medical University Hospital, Taichung, Taiwan.,Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Shinn-Zong Lin
- Department of Neurosurgery, Tzu Chi University Hospital, Hualien, Taiwan.,Bioinnovation Center, Tzu Chi foundation, Hualien, Taiwan
| | - Nen-Chung Chang
- Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Division of Cardiology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan
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41
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Liu X, Huang S, Liu C, Liu X, Shen Y, Cui Z. PPP1CC is associated with astrocyte and microglia proliferation after traumatic spinal cord injury in rats. Pathol Res Pract 2017; 213:1355-1364. [DOI: 10.1016/j.prp.2017.09.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 09/15/2017] [Accepted: 09/16/2017] [Indexed: 10/18/2022]
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Kim JH, Kim JY, Mun CH, Suh M, Lee JE. Agmatine Modulates the Phenotype of Macrophage Acute Phase after Spinal Cord Injury in Rats. Exp Neurobiol 2017; 26:278-286. [PMID: 29093636 PMCID: PMC5661060 DOI: 10.5607/en.2017.26.5.278] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 08/29/2017] [Accepted: 09/24/2017] [Indexed: 12/26/2022] Open
Abstract
Agmatine is a decarboxylated arginine by arginine decarboxylase. Agmatine is known to be a neuroprotective agent. It has been reported that agmatine works as a NMDA receptor blocker or a competitive nitric oxide synthase inhibitor in CNS injuries. In spinal cord injury, agmatine showed reduction of neuropathic pain, improvement of locomotor function, and neuroprotection. Macrophage is a key cellular component in neuroinflammation, a major cause of impairment after spinal cord injury. Macrophage has subtypes, M1 and M2 macrophages. M1 macrophage induces a pro-inflammatory response, but M2 inspires an anti-inflammatory response. In this study, it was clarified whether the neuroprotective effect of agmatine is related with the modulation of macrophage subdivision after spinal cord injury. Spinal cord injury was induced in rats with contusion using MASCIS. Animals received agmatine (100 mg/kg, IP) daily for 6 days beginning the day after spinal cord injury. The proportion of M1 and M2 macrophages are confirmed with immunohistochemistry and FACS. CD206+ & ED1+ cells were counted as M2 macrophages. The systemic treatment of agmatine increased M2 macrophages caudal side to epicenter 1 week after spinal cord injury in immunohistochemistry. M2 macrophage related markers, Arginase-1 and CD206 mRNA, were increased in the agmatine treatment group and M2 macrophage expressing and stimulated cytokine, IL-10 mRNA, also was significantly overexpressed by agmatine injection. Among BMPs, BMP2/4/7, agmatine significantly increased only the expression of BMP2 known to reduce M1 macrophage under inflammatory status. These results suggest that agmatine reduces impairment after spinal cord injury through modulating the macrophage phenotype.
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Affiliation(s)
- Jae Hwan Kim
- Center for Neuroscience Imaging Research, Institute for Basic Science (IBS), Sungkyunkwan University (SKKU), Suwon 16419, Korea.,Department of Biomedical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Korea.,Department of Anatomy, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Jae Young Kim
- Department of Anatomy, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Chin Hee Mun
- Division of Rheumatology, Department of Internal Medicine, Institute for Immunology and Immunological Disease, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Minah Suh
- Center for Neuroscience Imaging Research, Institute for Basic Science (IBS), Sungkyunkwan University (SKKU), Suwon 16419, Korea.,Department of Biomedical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Korea
| | - Jong Eun Lee
- Department of Anatomy, Yonsei University College of Medicine, Seoul 03722, Korea.,BK21 PLUS Project for Medical Science and Brain Research Institute, Yonsei University College of Medicine, Seoul 03722, Korea
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Toledano Furman NE, Prabhakara KS, Bedi S, Cox CS, Olson SD. OMIP-041: Optimized multicolor immunofluorescence panel rat microglial staining protocol. Cytometry A 2017; 93:182-185. [DOI: 10.1002/cyto.a.23267] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 09/14/2017] [Accepted: 09/26/2017] [Indexed: 12/31/2022]
Affiliation(s)
- Naama E. Toledano Furman
- Department of Pediatric Surgery; McGovern Medical School, The University of Texas Health Science Center; Houston Texas
| | - Karthik S. Prabhakara
- Department of Pediatric Surgery; McGovern Medical School, The University of Texas Health Science Center; Houston Texas
| | - Supinder Bedi
- Department of Pediatric Surgery; McGovern Medical School, The University of Texas Health Science Center; Houston Texas
| | - Charles S. Cox
- Department of Pediatric Surgery; McGovern Medical School, The University of Texas Health Science Center; Houston Texas
| | - Scott D. Olson
- Department of Pediatric Surgery; McGovern Medical School, The University of Texas Health Science Center; Houston Texas
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Liu M, Deng M, Ma Y. Differently polarized macrophages affect the viability and growth of NSPCs by regulating the expression of PACAP. Neuropeptides 2017; 65:114-119. [PMID: 28751044 DOI: 10.1016/j.npep.2017.07.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Revised: 04/29/2017] [Accepted: 07/05/2017] [Indexed: 01/07/2023]
Abstract
UNLABELLED Objective To explore the influence of differently polarized macrophages, M1 or M2, to viability and growth of NSPCs and its possible mechanism, especially the role of pituitary adenylate cyclase-activating polypeptide (PACAP) in it. METHOD Spinal cord-derived NSPCs were co-cultured with M1 or M2 through a transwell system. Growth of NSPCs in both groups was observed through an inverted microscope within 3days. NSPCs viability of each group, represented as intracellular ATP levels, was measured using the Cellular ATP Kit HTS following co-culture for 24h. PACAP levels in the co-cultured NSPCs was alleviated with immunofluorescence and Western blot analysis. RESULTS Morphologically NSPCs demonstrated a long spindle shape with short sprout on 3rd day when cultured together with M2. NSPCs cultured with M1 showed a small circle or oval shape with no obvious sprout. Expression of PACAP was observed in NSPCs co-cultured with M2 through immunofluorescence. In contrast, NSPCs did not demonstrate PACAP staining in the presence of M1 or cultured alone. PACAP in the NSPCs co-cultured with M2 was upregulated significantly compared with that co-cultured with M1 according to Western blot method. The relative ATP level of NSPCs co-cultured with M1 was markedly decreased while that with M2 was elevated significantly. That trend could be relieved by exogenous PACAP or PACAP 6-38. Viability change of NSPCs by M1/M2 correlated with apoptosis. CONCLUSION Differently polarized macrophages could affect the growth and viability of NSPCs by regulating the expression of PACAP.
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Affiliation(s)
- Min Liu
- Department of Immunology, School of Medicine, Wuhan University, Wuhan 430071, China
| | - Ming Deng
- Department of Orthopaedics, Renmin Hospital, Wuhan University, Wuhan City 430060, China
| | - Yonggang Ma
- Department of Orthopaedics, Renmin Hospital, Wuhan University, Wuhan City 430060, China.
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Lan X, Han X, Li Q, Yang QW, Wang J. Modulators of microglial activation and polarization after intracerebral haemorrhage. Nat Rev Neurol 2017; 13:420-433. [PMID: 28524175 PMCID: PMC5575938 DOI: 10.1038/nrneurol.2017.69] [Citation(s) in RCA: 548] [Impact Index Per Article: 78.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Intracerebral haemorrhage (ICH) is the most lethal subtype of stroke but currently lacks effective treatment. Microglia are among the first non-neuronal cells on the scene during the innate immune response to ICH. Microglia respond to acute brain injury by becoming activated and developing classic M1-like (proinflammatory) or alternative M2-like (anti-inflammatory) phenotypes. This polarization implies as yet unrecognized actions of microglia in ICH pathology and recovery, perhaps involving microglial production of proinflammatory or anti-inflammatory cytokines and chemokines. Furthermore, alternatively activated M2-like microglia might promote phagocytosis of red blood cells and tissue debris, a major contribution to haematoma clearance. Interactions between microglia and other cells modulate microglial activation and function, and are also important in ICH pathology. This Review summarizes key studies on modulators of microglial activation and polarization after ICH, including M1-like and M2-like microglial phenotype markers, transcription factors and key signalling pathways. Microglial phagocytosis, haematoma resolution, and the potential crosstalk between microglia and T lymphocytes, neurons, astrocytes, and oligodendrocytes in the ICH brain are described. Finally, the clinical and translational implications of microglial polarization in ICH are presented, including the evidence that therapeutic approaches aimed at modulating microglial function might mitigate ICH injury and improve brain repair.
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Affiliation(s)
- Xi Lan
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 720 Rutland Avenue, Ross Building 370B, Baltimore, Maryland 21205, USA
| | - Xiaoning Han
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 720 Rutland Avenue, Ross Building 370B, Baltimore, Maryland 21205, USA
| | - Qian Li
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 720 Rutland Avenue, Ross Building 370B, Baltimore, Maryland 21205, USA
| | - Qing-Wu Yang
- Department of Neurology, Xinqiao Hospital, Third Military Medical University, 183 Xinqiao Main Street, Shapingba District, Chongqing 400037, China
| | - Jian Wang
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 720 Rutland Avenue, Ross Building 370B, Baltimore, Maryland 21205, USA
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Zhang Y, Li H. Reprogramming Interferon Regulatory Factor Signaling in Cardiometabolic Diseases. Physiology (Bethesda) 2017; 32:210-223. [PMID: 28404737 DOI: 10.1152/physiol.00038.2016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 02/06/2017] [Accepted: 02/09/2017] [Indexed: 01/12/2023] Open
Abstract
Interferon regulatory factors (IRFs) are evolutionarily conserved proteins expressed not only in immune cells but also in other tissues and organs outside the immune system. In this review, we discuss mechanisms responsible for IRF-mediated innate immune responses and the function and mechanism of IRFs in cardiometabolic diseases. We focus on the role of IRFs in innate immunity and cardiometabolic homeostasis, and highlight reprogrammed IRF signaling.
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Affiliation(s)
- Yaxing Zhang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, People's Republic of China
- Institute of Model Animal, Wuhan University, Wuhan, People's Republic of China; and
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan, People's Republic of China
| | - Hongliang Li
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, People's Republic of China
- Institute of Model Animal, Wuhan University, Wuhan, People's Republic of China; and
- Medical Research Institute, School of Medicine, Wuhan University, Wuhan, People's Republic of China
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Combined effect of BCG vaccination and enriched environment promote neurogenesis and spatial cognition via a shift in meningeal macrophage M2 polarization. J Neuroinflammation 2017; 14:32. [PMID: 28183352 PMCID: PMC5301319 DOI: 10.1186/s12974-017-0808-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 02/01/2017] [Indexed: 02/08/2023] Open
Abstract
Background The spatial learning abilities of developing mice benefit from extrinsic cues, such as an enriched environment, with concomitant enhancement in cognitive functions. Interestingly, such enhancements can be further increased through intrinsic Bacillus Calmette-Guérin (BCG) vaccination. Results Here, we first report that combined neonatal BCG vaccination and exposure to an enriched environment (Enr) induced combined neurobeneficial effects, including hippocampal long-term potentiation, and increased neurogenesis and spatial learning and memory, in mice exposed to the Enr and vaccinated with BCG relative to those in the Enr that did not receive BCG vaccination. Neonatal BCG vaccination markedly induced anti-inflammatory meningeal macrophage polarization both in regular and Enr breeding mice. The meninges are composed of the pia mater, dura mater, and choroid plexus. Alternatively, this anti-inflammatory activity of the meninges occurred simultaneously with increased expression of the neurotrophic factors BDNF/IGF-1 and the M2 microglial phenotype in the hippocampus. Our results reveal a critical role for BCG vaccination in the regulation of neurogenesis and spatial cognition through meningeal macrophage M2 polarization and neurotrophic factor expression; these effects were completely or partially prevented by minocycline or anti-IL-10 antibody treatment, respectively. Conclusions Together, we first claim that immunological factor and environmental factor induce a combined effect on neurogenesis and cognition via a common pathway-meningeal macrophage M2 polarization. We also present a novel functional association between peripheral T lymphocytes and meningeal macrophages after evoking adaptive immune responses in the periphery whereby T lymphocytes are recruited to the meninges in response to systemic IFN-γ signaling. This leads to meningeal macrophage M2 polarization, subsequent to microglial M2 activation and neurotrophic factor expression, and eventually promotes a positive behavior. Electronic supplementary material The online version of this article (doi:10.1186/s12974-017-0808-7) contains supplementary material, which is available to authorized users.
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Turner RC, Naser ZJ, Lucke-Wold BP, Logsdon AF, Vangilder RL, Matsumoto RR, Huber JD, Rosen CL. Single low-dose lipopolysaccharide preconditioning: neuroprotective against axonal injury and modulates glial cells. NEUROIMMUNOLOGY AND NEUROINFLAMMATION 2017; 4:6-15. [PMID: 28164149 PMCID: PMC5289820 DOI: 10.20517/2347-8659.2016.40] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Aim Over 7 million traumatic brain injuries (TBI) are reported each year in the United States. However, treatments and neuroprotection following TBI are limited because secondary injury cascades are poorly understood. Lipopolysaccharide (LPS) administration before controlled cortical impact can contribute to neuroprotection. However, the underlying mechanisms and whether LPS preconditioning confers neuroprotection against closed-head injuries remains unclear. Methods The authors hypothesized that preconditioning with a low dose of LPS (0.2 mg/kg) would regulate glial reactivity and protect against diffuse axonal injury induced by weight drop. LPS was administered 7 days prior to TBI. LPS administration reduced locomotion, which recovered completely by time of injury. Results LPS preconditioning significantly reduced the post-injury gliosis response near the corpus callosum, possibly by downregulating the oncostatin M receptor. These novel findings demonstrate a protective role of LPS preconditioning against diffuse axonal injury. LPS preconditioning successfully prevented neurodegeneration near the corpus callosum, as measured by fluorojade B. Conclusion Further work is required to elucidate whether LPS preconditioning confers long-term protection against behavioral deficits and to elucidate the biochemical mechanisms responsible for LPS-induced neuroprotective effects.
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Affiliation(s)
- Ryan C Turner
- Department of Neurosurgery, West Virginia University, School of Medicine, Morgantown, WV 26506, USA; Center for Neuroscience, West Virginia University, School of Medicine, Morgantown, WV 26506, USA
| | - Zachary J Naser
- Department of Neurosurgery, West Virginia University, School of Medicine, Morgantown, WV 26506, USA; Center for Neuroscience, West Virginia University, School of Medicine, Morgantown, WV 26506, USA
| | - Brandon P Lucke-Wold
- Department of Neurosurgery, West Virginia University, School of Medicine, Morgantown, WV 26506, USA; Center for Neuroscience, West Virginia University, School of Medicine, Morgantown, WV 26506, USA
| | - Aric F Logsdon
- Center for Neuroscience, West Virginia University, School of Medicine, Morgantown, WV 26506, USA; Department of Basic Pharmaceutical Sciences, West Virginia University, School of Pharmacy, Morgantown, WV 26506, USA
| | - Reyna L Vangilder
- Center for Neuroscience, West Virginia University, School of Medicine, Morgantown, WV 26506, USA; Center for Health Restoration, West Virginia University, School of Nursing, Morgantown, WV 26506, USA
| | - Rae R Matsumoto
- Center for Neuroscience, West Virginia University, School of Medicine, Morgantown, WV 26506, USA; Department of Basic Pharmaceutical Sciences, West Virginia University, School of Pharmacy, Morgantown, WV 26506, USA
| | - Jason D Huber
- Center for Neuroscience, West Virginia University, School of Medicine, Morgantown, WV 26506, USA; Department of Basic Pharmaceutical Sciences, West Virginia University, School of Pharmacy, Morgantown, WV 26506, USA
| | - Charles L Rosen
- Department of Neurosurgery, West Virginia University, School of Medicine, Morgantown, WV 26506, USA; Center for Neuroscience, West Virginia University, School of Medicine, Morgantown, WV 26506, USA
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Endesfelder S, Weichelt U, Strauß E, Schlör A, Sifringer M, Scheuer T, Bührer C, Schmitz T. Neuroprotection by Caffeine in Hyperoxia-Induced Neonatal Brain Injury. Int J Mol Sci 2017; 18:E187. [PMID: 28106777 PMCID: PMC5297819 DOI: 10.3390/ijms18010187] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 01/04/2017] [Accepted: 01/12/2017] [Indexed: 12/11/2022] Open
Abstract
Sequelae of prematurity triggered by oxidative stress and free radical-mediated tissue damage have coined the term "oxygen radical disease of prematurity". Caffeine, a potent free radical scavenger and adenosine receptor antagonist, reduces rates of brain damage in preterm infants. In the present study, we investigated the effects of caffeine on oxidative stress markers, anti-oxidative response, inflammation, redox-sensitive transcription factors, apoptosis, and extracellular matrix following the induction of hyperoxia in neonatal rats. The brain of a rat pups at postnatal Day 6 (P6) corresponds to that of a human fetal brain at 28-32 weeks gestation and the neonatal rat is an ideal model in which to investigate effects of oxidative stress and neuroprotection of caffeine on the developing brain. Six-day-old Wistar rats were pre-treated with caffeine and exposed to 80% oxygen for 24 and 48 h. Caffeine reduced oxidative stress marker (heme oxygenase-1, lipid peroxidation, hydrogen peroxide, and glutamate-cysteine ligase catalytic subunit (GCLC)), promoted anti-oxidative response (superoxide dismutase, peroxiredoxin 1, and sulfiredoxin 1), down-regulated pro-inflammatory cytokines, modulated redox-sensitive transcription factor expression (Nrf2/Keap1, and NFκB), reduced pro-apoptotic effectors (poly (ADP-ribose) polymerase-1 (PARP-1), apoptosis inducing factor (AIF), and caspase-3), and diminished extracellular matrix degeneration (matrix metalloproteinases (MMP) 2, and inhibitor of metalloproteinase (TIMP) 1/2). Our study affirms that caffeine is a pleiotropic neuroprotective drug in the developing brain due to its anti-oxidant, anti-inflammatory, and anti-apoptotic properties.
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Affiliation(s)
- Stefanie Endesfelder
- Department of Neonatology, Charité, Universitätsmedizin Berlin, 13353 Berlin, Germany.
| | - Ulrike Weichelt
- Department of Physiology, Charité, Universitätsmedizin Berlin, 10117 Berlin, Germany.
| | - Evelyn Strauß
- Department of Neonatology, Charité, Universitätsmedizin Berlin, 13353 Berlin, Germany.
| | - Anja Schlör
- Department of Biochemistry and Biology, University of Potsdam, 14476 Potsdam, Germany.
| | - Marco Sifringer
- Department of Anesthesiology and Intensive Care Medicine, Charité, Universitätsmedizin Berlin, 13353 Berlin, Germany.
| | - Till Scheuer
- Department of Neonatology, Charité, Universitätsmedizin Berlin, 13353 Berlin, Germany.
| | - Christoph Bührer
- Department of Neonatology, Charité, Universitätsmedizin Berlin, 13353 Berlin, Germany.
| | - Thomas Schmitz
- Department of Neonatology, Charité, Universitätsmedizin Berlin, 13353 Berlin, Germany.
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Pourgonabadi S, Müller HD, Mendes JR, Gruber R. Saliva initiates the formation of pro-inflammatory macrophages in vitro. Arch Oral Biol 2016; 73:295-301. [PMID: 27825074 DOI: 10.1016/j.archoralbio.2016.10.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 07/26/2016] [Accepted: 10/14/2016] [Indexed: 01/12/2023]
Abstract
OBJECTIVES Saliva can support oral wound healing, a process that requires a temporary inflammatory reaction. We have reported previously that saliva provokes a strong inflammatory response in oral fibroblasts. Bone marrow cells also give rise to macrophages, a heterogeneous subset of cell population involved in wound healing. Lipopolysaccharide (LPS) and interleukin 4 (IL-4) induce activation of pro-(M1), and anti-(M2) inflammatory macrophages, respectively. Yet, the impact of saliva on programming bone marrow cells into either M1 or M2 macrophages remains unclear . DESIGN Herein, we examined whether sterile saliva affects the in vitro process of macrophage polarization based on murine bone marrow cultures and RAW264.7 mouse macrophages. RESULTS We report that sterile saliva, similar to lipopolysaccharides, provoked a robust activation of the M1 phenotype which is characterized by a strong increase of the respective genes IL-12 and IL-6, based on a real-time gene expression analysis, and for IL-6 with immunoassay. Arginase-1 and Ym1, both genes characteristic for the M2 phenotype, were not considerably modulated by saliva. Inhibition of TLR4 signaling with TAK-242, blocking NFκB signaling with Bay 11-7085, but also autoclaving saliva greatly reduced the development of the M1 phenotype. CONCLUSION These data suggest that saliva activates the TLR4 dependent polarization into pro-inflammatory M1 macrophages in vitro.
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Affiliation(s)
- Solmaz Pourgonabadi
- Department of Oral Biology, Dental School, Medical University of Vienna, Austria
| | - Heinz-Dieter Müller
- Department of Oral Biology, Dental School, Medical University of Vienna, Austria; Department of Preventive, Restorative and Pediatric Dentistry, School of Dental Medicine, University of Bern, Switzerland
| | - João Rui Mendes
- Department of Oral Biology, Dental School, Medical University of Vienna, Austria
| | - Reinhard Gruber
- Department of Oral Biology, Dental School, Medical University of Vienna, Austria; Department of Preventive, Restorative and Pediatric Dentistry, School of Dental Medicine, University of Bern, Switzerland; Austrian Cluster for Tissue Regeneration, Austria.
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