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Marino N, Bedeschi M, Vaccari ME, Cambiaghi M, Tesei A. Glitches in the brain: the dangerous relationship between radiotherapy and brain fog. Front Cell Neurosci 2024; 18:1328361. [PMID: 38515789 PMCID: PMC10956129 DOI: 10.3389/fncel.2024.1328361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 02/22/2024] [Indexed: 03/23/2024] Open
Abstract
Up to approximately 70% of cancer survivors report persistent deficits in memory, attention, speed of information processing, multi-tasking, and mental health functioning, a series of symptoms known as "brain fog." The severity and duration of such effects can vary depending on age, cancer type, and treatment regimens. In particular, every year, hundreds of thousands of patients worldwide undergo radiotherapy (RT) for primary brain tumors and brain metastases originating from extracranial tumors. Besides its potential benefits in the control of tumor progression, recent studies indicate that RT reprograms the brain tumor microenvironment inducing increased activation of microglia and astrocytes and a consequent general condition of neuroinflammation that in case it becomes chronic could lead to a cognitive decline. Furthermore, radiation can induce endothelium reticulum (ER) stress directly or indirectly by generating reactive oxygen species (ROS) activating compensatory survival signaling pathways in the RT-surviving fraction of healthy neuronal and glial cells. In particular, the anomalous accumulation of misfolding proteins in neuronal cells exposed to radiation as a consequence of excessive activation of unfolded protein response (UPR) could pave the way to neurodegenerative disorders. Moreover, exposure of cells to ionizing radiation was also shown to affect the normal proteasome activity, slowing the degradation rate of misfolded proteins, and further exacerbating ER-stress conditions. This compromises several neuronal functions, with neuronal accumulation of ubiquitinated proteins with a consequent switch from proteasome to immunoproteasome that increases neuroinflammation, a crucial risk factor for neurodegeneration. The etiology of brain fog remains elusive and can arise not only during treatment but can also persist for an extended period after the end of RT. In this review, we will focus on the molecular pathways triggered by radiation therapy affecting cognitive functions and potentially at the origin of so-called "brain fog" symptomatology, with the aim to define novel therapeutic strategies to preserve healthy brain tissue from cognitive decline.
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Affiliation(s)
- Noemi Marino
- Bioscience Laboratory, IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) “Dino Amadori”, Meldola, Italy
| | - Martina Bedeschi
- Bioscience Laboratory, IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) “Dino Amadori”, Meldola, Italy
| | - Melania Elettra Vaccari
- Bioscience Laboratory, IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) “Dino Amadori”, Meldola, Italy
| | - Marco Cambiaghi
- Bioscience Laboratory, IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) “Dino Amadori”, Meldola, Italy
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Anna Tesei
- Bioscience Laboratory, IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) “Dino Amadori”, Meldola, Italy
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Bi W, Cheng X, Zeng Z, Zhou R, Luo R, Zhang J, Zhu L. Rifampicin ameliorates lipopolysaccharide-induced cognitive and motor impairments via inhibition of the TLR4/MyD88/NF-κB signaling pathway in mice. Neurol Res 2021; 43:358-371. [PMID: 33749522 DOI: 10.1080/01616412.2020.1866353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
OBJECTIVES Aberrant microglial responses promote neuroinflammation in neurodegenerative diseases. However, rifampicin's effect on cognitive and motor sequelae of inflammation remains unknown. Therefore, we investigated whether rifampicin exerts neuroprotection against lipopolysaccharide (LPS)-induced cognitive and motor impairments. METHODS A mouse model of LPS-induced cognitive and motor impairment was established. Adult C57BL/6 mice were injected intraperitoneally with 25 mg/kg rifampicin 30 min before intraperitoneal microinjection of LPS (750 μg/kg) daily until study end. Treatments and behavioral experiments were performed once daily for 7 days. Behavioral tests and pathological/biochemical assays were performed to evaluate LPS-induced damage to the hippocampus and substantia nigra (SN). RESULTS Rifampicin attenuated LPS-induced cognitive and motor impairments, based on performance in the behavioral tests. Rifampicin suppressed the release of pro-inflammatory mediators, including tumor necrosis factor-α, interleukin-1β, and prostaglandin E2 in the serum and nitric oxide (NO) in brain tissue, and cyclooxygenase-2 and inducible nitric oxide synthase levels. Immunofluorescence revealed that rifampicin inhibited LPS-induced microglial activation in the hippocampus and SN, thus protecting the neurons. Rifampicin inhibited the activation of the toll-like receptor 4 (TLR4)/myeloid differentiation primary response 88 (MyD88)/nuclear factor kappa B (NF-κB) signaling pathway. Rifampicin downregulated TLR4 and MyD88 protein levels and inhibited NF-κB inhibitor alpha and NF-κB inhibitor kinase beta phosphorylation, thus reducing p65 nuclear transfer by inhibiting NF-κB signaling activation in LPS-treated mice. CONCLUSION Rifampicin protects against LPS-induced neuroinflammation and attenuates cognitive and motor impairments by inhibiting the TLR4/MyD88/NF-κB signaling pathway. Our findings might aid the development of novel therapies to treat progressive neurodegenerative diseases.
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Affiliation(s)
- Wei Bi
- Department of Neurology, The First Affiliated Hospital of Jinan University, Guangzhou PR China.,Clinical Neuroscience Institute, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong Province, China
| | - Xiaofeng Cheng
- Department of Neurology, The First Affiliated Hospital of Jinan University, Guangzhou PR China
| | - Zhaohao Zeng
- Department of Neurology, The First Affiliated Hospital of Jinan University, Guangzhou PR China
| | - Ruiyi Zhou
- Department of Neurology, The First Affiliated Hospital of Jinan University, Guangzhou PR China
| | - Rixin Luo
- Department of Neurology, The First Affiliated Hospital of Jinan University, Guangzhou PR China
| | - Jiawei Zhang
- Department of Pathophysiology, School of Medicine, Jinan University, Guangzhou, PR China
| | - Lihong Zhu
- Department of Pathophysiology, School of Medicine, Jinan University, Guangzhou, PR China
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3
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Ginsenoside Rd attenuates blood-brain barrier damage by suppressing proteasome-mediated signaling after transient forebrain ischemia. Neuroreport 2020; 31:466-472. [DOI: 10.1097/wnr.0000000000001426] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Liang Y, Zhou T, Chen Y, Lin D, Jing X, Peng S, Zheng D, Zeng Z, Lei M, Wu X, Huang K, Yang L, Xiao S, Liu J, Tao E. Rifampicin inhibits rotenone-induced microglial inflammation via enhancement of autophagy. Neurotoxicology 2017; 63:137-145. [PMID: 28986232 DOI: 10.1016/j.neuro.2017.09.015] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 09/30/2017] [Accepted: 09/30/2017] [Indexed: 12/16/2022]
Abstract
Mitochondrial and autophagic dysfunction, as well as neuroinflammation, are associated with the pathophysiology of Parkinson's disease (PD). Rotenone, an inhibitor of mitochondrial complex I, has been associated as an environmental neurotoxin related to PD. Our previous studies reported that rifampicin inhibited microglia activation and production of proinflammatory mediators induced by rotenone, but the precise mechanism has not been completely elucidated. BV2 cells were pretreated for 2h with rifampicin followed by 0.1μM rotenone, alone or in combination with chloroquine. Here, we demonstrate that rifampicin pretreatment alleviated rotenone induced release of IL-1β and IL-6, and its effects were suppressed when autophagy was inhibited by chloroquine. Moreover, preconditioning with 50μM rifampicin significantly increased viability of SH-SY5Y cells cocultured with rotenone-treated BV2 cells in the transwell coculture system. Chloroquine partially abolished the neuroprotective effects of rifampicin pretreatment. Rifampicin pretreatment significantly reversed rotenone-induced mitochondrial membrane potential reduction and reactive oxygen species accumulation. We suggest that the mechanism for rifampicin-mediated anti-inflammatory and antioxidant effects is the enhancement of autophagy. Indeed, the ratio of LC3-II/LC3-I in rifampicin-pretreated BV2 cells was significantly higher than that in cells without pretreatment. Fluorescence and electron microscopy analyses indicate an increase of lysosomes colocalized with mitochondria in cells pretreated with rifampicin, which confirms that the damaged mitochondria were cleared through autophagy (mitophagy). Taken together, the data provide further evidence that rifampicin exerts neuroprotection against rotenone-induced microglia inflammation, partially through the autophagy pathway. Modulation of autophagy by rifampicin is a novel therapeutic strategy for PD.
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Affiliation(s)
- Yanran Liang
- Department of Neurology, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China
| | - Tianen Zhou
- Department of Emergency, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China
| | - Ying Chen
- Department of Neurology, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China
| | - Danyu Lin
- Department of Neurology, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China
| | - Xiuna Jing
- Department of Neurology, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China
| | - Sudan Peng
- Department of Neurology, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China
| | - Dezhi Zheng
- Department of Neurology, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China
| | - Zhifen Zeng
- Department of Neurology, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China
| | - Ming Lei
- Department of Neurology, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China
| | - Xia Wu
- Department of Neurology, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China
| | - Kaixun Huang
- Department of Neurology, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China
| | - Lianhong Yang
- Department of Neurology, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China
| | - Songhua Xiao
- Department of Neurology, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China
| | - Jun Liu
- Department of Neurology, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China
| | - Enxiang Tao
- Department of Neurology, The Sun Yat-sen Memorial Hospital of Sun Yat-sen University, 107 Yanjiang West Road, Guangzhou 510080, China.
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Figueiredo-Pereira ME, Rockwell P, Schmidt-Glenewinkel T, Serrano P. Neuroinflammation and J2 prostaglandins: linking impairment of the ubiquitin-proteasome pathway and mitochondria to neurodegeneration. Front Mol Neurosci 2015; 7:104. [PMID: 25628533 PMCID: PMC4292445 DOI: 10.3389/fnmol.2014.00104] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 12/17/2014] [Indexed: 12/13/2022] Open
Abstract
The immune response of the CNS is a defense mechanism activated upon injury to initiate repair mechanisms while chronic over-activation of the CNS immune system (termed neuroinflammation) may exacerbate injury. The latter is implicated in a variety of neurological and neurodegenerative disorders such as Alzheimer and Parkinson diseases, amyotrophic lateral sclerosis, multiple sclerosis, traumatic brain injury, HIV dementia, and prion diseases. Cyclooxygenases (COX-1 and COX-2), which are key enzymes in the conversion of arachidonic acid into bioactive prostanoids, play a central role in the inflammatory cascade. J2 prostaglandins are endogenous toxic products of cyclooxygenases, and because their levels are significantly increased upon brain injury, they are actively involved in neuronal dysfunction induced by pro-inflammatory stimuli. In this review, we highlight the mechanisms by which J2 prostaglandins (1) exert their actions, (2) potentially contribute to the transition from acute to chronic inflammation and to the spreading of neuropathology, (3) disturb the ubiquitin-proteasome pathway and mitochondrial function, and (4) contribute to neurodegenerative disorders such as Alzheimer and Parkinson diseases, and amyotrophic lateral sclerosis, as well as stroke, traumatic brain injury (TBI), and demyelination in Krabbe disease. We conclude by discussing the therapeutic potential of targeting the J2 prostaglandin pathway to prevent/delay neurodegeneration associated with neuroinflammation. In this context, we suggest a shift from the traditional view that cyclooxygenases are the most appropriate targets to treat neuroinflammation, to the notion that J2 prostaglandin pathways and other neurotoxic prostaglandins downstream from cyclooxygenases, would offer significant benefits as more effective therapeutic targets to treat chronic neurodegenerative diseases, while minimizing adverse side effects.
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Affiliation(s)
- Maria E Figueiredo-Pereira
- Department of Biological Sciences, Hunter College, The Graduate School and University Center, City University of New York New York, NY, USA
| | - Patricia Rockwell
- Department of Biological Sciences, Hunter College, The Graduate School and University Center, City University of New York New York, NY, USA
| | - Thomas Schmidt-Glenewinkel
- Department of Biological Sciences, Hunter College, The Graduate School and University Center, City University of New York New York, NY, USA
| | - Peter Serrano
- Department of Psychology, Hunter College, The Graduate School and University Center, City University of New York New York, NY, USA
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Zhu L, Bi W, Lu D, Zhang C, Shu X, Wang H, Qi R, Shi Q, Lu D. Regulation of ubiquitin-specific processing protease 8 suppresses neuroinflammation. Mol Cell Neurosci 2015; 64:74-83. [PMID: 24861766 DOI: 10.1016/j.mcn.2014.05.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 03/14/2014] [Accepted: 05/21/2014] [Indexed: 02/05/2023] Open
Abstract
In our previous study, we reported that luteolin might exert neuroprotective functions by inhibiting the production of proinflammatory mediators, thereby suppressing microglial activation. In this study, we used two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS) to study the effect of ubiquitin-specific processing protease 8 (USP8) in luteolin-treated microglia. Western blot analysis verified that USP8 expression is upregulated by luteolin. Researchers have found that USP8 markedly enhanced the stability of neuregulin receptor degradation protein-1 (Nrdp1), which in turn inhibited the production of proinflammatory cytokines in toll-like receptor-triggered macrophages. We next hypothesized that luteolin inhibits microglial inflammation by regulating USP8 gene expression. After transfecting BV2-immortalized murine microglial cells with USP8, a significant reduction in the degradation of Nrdp1 was observed. USP8 overexpression also reduced the production of lipopolysaccharide (LPS)-induced proinflammatory mediators such as inducible nitric oxide synthase (iNOS), nitric oxide (NO), cyclooxygenase-2 (COX-2), and prostaglandin E2 (PGE2). We also found that USP8 siRNA blocked luteolin inhibition of pro-inflammatory gene expression such as iNOS, NO, COX-2, and PGE2. Taken together, our findings suggested that luteolin inhibits microglial inflammation by enhancing USP8 protein production. We concluded that in addition to anti-inflammatory luteolin, USP8 might represent a novel mechanism for the treatment of neuroinflammation and neurodegeneration.
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Affiliation(s)
- Lihong Zhu
- Department of Pathophysiology, Institute of Brain Research, School of Medicine, JiNan University, Guangzhou 510632, PR China
| | - Wei Bi
- Department of Neurology, First Affiliated Hospital of JiNan University, Guangzhou 510630, PR China
| | - Dan Lu
- Department of Pathophysiology, Institute of Brain Research, School of Medicine, JiNan University, Guangzhou 510632, PR China
| | - Chanjuan Zhang
- Department of Pathophysiology, Institute of Brain Research, School of Medicine, JiNan University, Guangzhou 510632, PR China
| | - Xiaoming Shu
- Department of Pathophysiology, Institute of Brain Research, School of Medicine, JiNan University, Guangzhou 510632, PR China
| | - Huadong Wang
- Department of Pathophysiology, Institute of Brain Research, School of Medicine, JiNan University, Guangzhou 510632, PR China
| | - Renbing Qi
- Department of Pathophysiology, Institute of Brain Research, School of Medicine, JiNan University, Guangzhou 510632, PR China
| | - Qiaoyun Shi
- Center for Inherited Cardiovascular Disease, Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, CA 94304, USA
| | - Daxiang Lu
- Department of Pathophysiology, Institute of Brain Research, School of Medicine, JiNan University, Guangzhou 510632, PR China.
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7
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BI WEI, ZHU LIHONG, JING XIUNA, ZENG ZHIFEN, LIANG YANRAN, XU ANDING, LIU JUN, XIAO SONGHUA, YANG LIANHONG, SHI QIAOYUN, GUO LI, TAO ENXIANG. Rifampicin improves neuronal apoptosis in LPS-stimulated co‑cultured BV2 cells through inhibition of the TLR-4 pathway. Mol Med Rep 2014; 10:1793-9. [PMID: 25119251 PMCID: PMC4148376 DOI: 10.3892/mmr.2014.2480] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 07/01/2014] [Indexed: 11/06/2022] Open
Abstract
Agents inhibiting microglial activation are attracting attention as candidate drugs for neuroprotection in neurodegenerative diseases. Recently, researchers have focused on the immunosuppression induced by rifampicin. Our previous study showed that rifampicin inhibits the production of lipopolysaccharide (LPS)-induced pro-inflammatory mediators and improves neuron survival in inflammation; however, the mechanism through which rifampicin inhibits microglial inflammation and its neuroprotective effects are not completely understood. In this study, we examined the effects of rifampicin on morphological changes induced by LPS in murine microglial BV2 cells. Then we investigated, in BV2 microglia, the effects of rifampicin on two signaling pathway componentss stimulated by LPS, the Toll‑like receptor-4 (TLR-4) and the nuclear factor-κB (NF-κB). In addition, we co-cultured BV2 microglia and neurons to observe the indirect neuroprotective effects of rifampicin. Rifampicin inhibited LPS-stimulated expression of the TLR-4 gene. When neurons were co-cultured with LPS-stimulated BV2 microglia, pre-treatment with rifampicin increased neuronal viability and reduced the number of apoptotic cells. Taken together, these findings suggest that rifampicin, with its anti-inflammatory properties, may be a promising agent for the treatment of neurodegenerative diseases.
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Affiliation(s)
- WEI BI
- Department of Neurology, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - LIHONG ZHU
- Department of Pathophysiology, Institute of Brain Research, School of Medicine, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - XIUNA JING
- Department of Neurology, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510120, P.R. China
| | - ZHIFEN ZENG
- Department of Neurology, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510120, P.R. China
| | - YANRAN LIANG
- Department of Neurology, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510120, P.R. China
| | - ANDING XU
- Department of Neurology, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - JUN LIU
- Department of Neurology, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510120, P.R. China
| | - SONGHUA XIAO
- Department of Neurology, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510120, P.R. China
| | - LIANHONG YANG
- Department of Neurology, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510120, P.R. China
| | - QIAOYUN SHI
- Center for Inherited Cardiovascular Disease, Division of Cardiovascular Medicine, Stanford University, School of Medicine, Stanford, CA 94304, USA
| | - LI GUO
- Department of Neurology, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - ENXIANG TAO
- Department of Neurology, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510120, P.R. China
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Jansen AHP, Reits EAJ, Hol EM. The ubiquitin proteasome system in glia and its role in neurodegenerative diseases. Front Mol Neurosci 2014; 7:73. [PMID: 25152710 PMCID: PMC4126450 DOI: 10.3389/fnmol.2014.00073] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 07/10/2014] [Indexed: 12/12/2022] Open
Abstract
The ubiquitin proteasome system (UPS) is crucial for intracellular protein homeostasis and for degradation of aberrant and damaged proteins. The accumulation of ubiquitinated proteins is a hallmark of many neurodegenerative diseases, including amyotrophic lateral sclerosis, Alzheimer’s, Parkinson’s, and Huntington’s disease, leading to the hypothesis that proteasomal impairment is contributing to these diseases. So far, most research related to the UPS in neurodegenerative diseases has been focused on neurons, while glial cells have been largely disregarded in this respect. However, glial cells are essential for proper neuronal function and adopt a reactive phenotype in neurodegenerative diseases, thereby contributing to an inflammatory response. This process is called reactive gliosis, which in turn affects UPS function in glial cells. In many neurodegenerative diseases, mostly neurons show accumulation and aggregation of ubiquitinated proteins, suggesting that glial cells may be better equipped to maintain proper protein homeostasis. During an inflammatory reaction, the immunoproteasome is induced in glia, which may contribute to a more efficient degradation of disease-related proteins. Here we review the role of the UPS in glial cells in various neurodegenerative diseases, and we discuss how studying glial cell function might provide essential information in unraveling mechanisms of neurodegenerative diseases.
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Affiliation(s)
- Anne H P Jansen
- Department of Cell Biology and Histology, Academic Medical Center Amsterdam, Netherlands
| | - Eric A J Reits
- Department of Cell Biology and Histology, Academic Medical Center Amsterdam, Netherlands
| | - Elly M Hol
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht Utrecht, Netherlands ; Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences Amsterdam, Netherlands ; Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam Netherlands
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Zhu L, Bi W, Lu D, Zhang C, Shu X, Lu D. Luteolin inhibits SH-SY5Y cell apoptosis through suppression of the nuclear transcription factor-κB, mitogen-activated protein kinase and protein kinase B pathways in lipopolysaccharide-stimulated cocultured BV2 cells. Exp Ther Med 2014; 7:1065-1070. [PMID: 24940388 PMCID: PMC3991549 DOI: 10.3892/etm.2014.1564] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 01/06/2014] [Indexed: 01/19/2023] Open
Abstract
Microglial activation is one of the causative factors for neuroinflammation, which is associated with the pathophysiology of neurodegenerative diseases. Our previous study showed that the flavonoid luteolin inhibited several pro-inflammatory enzymes and pro-inflammatory cytokines that are induced by activated microglia; however, its effect on signaling pathways is currently unknown. The present study examined the effects of luteolin on signaling pathways stimulated by lipopolysaccharide (LPS), including Toll-like receptor-4 (TLR-4), nuclear transcription factor-κB (NF-κB), mitogen-activated protein kinase (MAPK) family and protein kinase B (Akt) pathways in murine microglial BV2 cells. In addition, BV2 microglia and SH-SY5Y neuroblastoma cells were cocultured to observe the indirect neuroprotective effects of luteolin. Luteolin inhibited the LPS-stimulated expression of TLR-4. In addition, luteolin blocked LPS-induced NF-κB, p38, JNK and Akt activation, but had no effect on ERK. When SH-SY5Y cells were cocultured with LPS-stimulated BV2 microglia, pretreatment with luteolin increased neuronal viability and reduced the number of apoptotic cells. These data suggest that luteolin has a beneficial effect on neuroinflammatory events in neurodegenerative diseases via suppression of the NF-κB, MAPK and Akt pathways in activated microglial cells.
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Affiliation(s)
- Lihong Zhu
- Department of Pathophysiology, Institute of Brain Research, School of Medicine, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Wei Bi
- Department of Neurology, First Affiliated Hospital of Jinan University, Guangzhou, Guangdong 510630, P.R. China
| | - Dan Lu
- Department of Pathophysiology, Institute of Brain Research, School of Medicine, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Chanjuan Zhang
- Department of Pathophysiology, Institute of Brain Research, School of Medicine, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Xiaoming Shu
- Department of Pathophysiology, Institute of Brain Research, School of Medicine, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Daxiang Lu
- Department of Pathophysiology, Institute of Brain Research, School of Medicine, Jinan University, Guangzhou, Guangdong 510632, P.R. China
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Bi W, Zhu L, Zeng Z, Jing X, Liang Y, Guo L, Shi Q, Xu A, Tao E. Investigations into the role of 26S proteasome non-ATPase regulatory subunit 13 in neuroinflammation. Neuroimmunomodulation 2014; 21:331-7. [PMID: 24642793 DOI: 10.1159/000357811] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 12/08/2013] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE To investigate 26S proteasome non-ATPase regulatory subunit 13 (PSMD13) gene silencing as a potential treatment for neuroinflammatory disorders via regulation of microglial activation and production of inflammatory mediators. METHODS RNA interference was used to knockdown PSMD13 gene expression, followed by inhibitors of κB (IκBα) protein degradation and nuclear factor κB (NF-κB) activity measurement in lipopolysaccharide (LPS)-stimulated BV2 microglia. Nitrite (Griess) assay, reporter gene assay, enzyme-linked immunosorbent assay and Western blot were used to investigate the role of PSMD13 in microglial activation and inflammation. RESULTS PSMD13 gene knockdown significantly reduced IκBα degradation and NF-κB activation in LPS-stimulated murine BV2 microglia. It also decreased the production of LPS-induced proinflammatory mediators, such as inducible nitric oxide synthase, nitric oxide, cyclooxygenase-2 and prostaglandin E2. CONCLUSIONS PSMD13 gene silencing suppressed the production of proinflammatory mediators by modulating ubiquitin-proteasome system-mediated neuroinflammation via the downregulation of IκBα degradation and NF-κB activation in LPS-stimulated BV2 microglia. PSMD13 gene knockdown may have therapeutic implications for the treatment of neuroinflammatory disorders.
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Affiliation(s)
- Wei Bi
- Department of Neurology, First Affiliated Hospital of Jinan University, Guangzhou, PR China
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11
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Niranjan R. Molecular Basis of Etiological Implications in Alzheimer’s Disease: Focus on Neuroinflammation. Mol Neurobiol 2013; 48:412-28. [DOI: 10.1007/s12035-013-8428-4] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Accepted: 02/06/2013] [Indexed: 12/31/2022]
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