Dataset Information

Atp13a2 Deficiency Aggravates Astrocyte-Mediated Neuroinflammation via NLRP3 Inflammasome Activation.

ABSTRACT:

Aim

Atp13a2 (Park9) gene encodes a transmembrane lysosomal P5-type ATPase (ATP13A2), and its missense or truncation mutations leads to lysosomal dysfunction and consequently results in neuronal death in the pathogenesis of Parkinson's disease (PD). Nevertheless, the roles of ATP13A2 in the biological features of astrocytes, especially in the regulation of PD-related neuroinflammation, have not been investigated.

Methods

We cultured primary neurons and astrocytes from mouse midbrain to investigate the mechanisms for astrocyte ATP13A2-regulated lysosomal function and neuroinflammation following 1-methyl-4-phenylpyridinium (MPP(+) ) treatment.

Results

We found that astrocytes expressed considerable levels of ATP13A2 and deficiency of ATP13A2 in astrocyte-induced intense inflammation, which exacerbated dopaminergic neuron damage after exposure to MPP(+) . Notably, lack of ATP13A2 increased lysosomal membrane permeabilization and cathepsin B release, which in turn exacerbated activation of nod-like receptor protein 3 (NLRP3) inflammasome to produce excess IL-1β from astrocytes. Furthermore, overexpression of ATP13A2 reversed MPP(+) -induced cathepsin B release and NLRP3 inflammasome activation in astrocytes.

Conclusions

Our results have revealed a novel role of ATP13A2 in modulating astrocyte-mediated neuroinflammation via NLRP3 inflammasome activation, thus bringing to light of a direct link between astrocyte lysosome and neuroinflammation in the pathological model of PD.

SUBMITTER: Qiao C

PROVIDER: S-EPMC6492810 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Atp13a2 Deficiency Aggravates Astrocyte-Mediated Neuroinflammation via NLRP3 Inflammasome Activation.

Qiao Chen C Yin Nuo N Gu Huan-Yu HY Zhu Jia-Lei JL Ding Jian-Hua JH Lu Ming M Hu Gang G

CNS neuroscience & therapeutics 20160205 6

<h4>Aim</h4>Atp13a2 (Park9) gene encodes a transmembrane lysosomal P5-type ATPase (ATP13A2), and its missense or truncation mutations leads to lysosomal dysfunction and consequently results in neuronal death in the pathogenesis of Parkinson's disease (PD). Nevertheless, the roles of ATP13A2 in the biological features of astrocytes, especially in the regulation of PD-related neuroinflammation, have not been investigated.<h4>Methods</h4>We cultured primary neurons and astrocytes from mouse midbrai ...[more]

PMID: 26848562

Similar Datasets

Project description:AimsAccumulating evidence has suggested that airborne fine particulate matter (PM2.5) exposure is associated with an increased risk of ischemic stroke. However, the underlying mechanisms have not been fully elucidated. In this study, we aim to investigate the role and mechanisms of NLRP3 inflammasome and pyroptosis in ischemic stroke after PM2.5 exposure.MethodsThe BV-2 and HMC-3 microglial cell lines were established and subjected to oxygen-glucose deprivation and reoxygenation (OGD/R) with or without PM2.5 exposure. We used the CCK-8 assay to explore the effects of PM2.5 on cell viability of BV-2 and HMC-3 cells. Then, the effects of PM2.5 exposure on NLRP3 inflammasome and pyroptosis following OGD/R were detected by western blotting, ELISA, and the confocal immunofluorescence staining. Afterwards, NLRP3 was knocked down to further validate the effects of PM2.5 on cell viability, NLRP3 inflammasome activation, and pyroptosis after OGD/R in HMC-3 cells. Finally, the intracellular reactive oxygen species (ROS) was measured and the ROS inhibitor N-acetyl-L-cysteine (NAC) was used to investigate whether ROS was required for PM2.5-induced NLRP3 inflammasome activation and pyroptosis under ischemic conditions.ResultsWe found that PM2.5 exposure decreased the viability of BV-2 and HMC-3 cells in a dose- and time-dependent manner under ischemic conditions. Furthermore, PM2.5 exposure aggravated NLRP3 inflammasome activation and pyroptosis after OGD/R, as indicated by an increased expression of NLRP3, ASC, pro-caspase-1, Caspase-1, GSDMD, and GSDMD-N; increased production of IL-1β and IL-18; and enhanced Caspase-1 activity and SYTOX green uptake. However, shRNA NLRP3 treatment attenuated the effects of PM2.5 on cell viability, NLRP3 inflammasome activation, and pyroptosis. Moreover, we observed that PM2.5 exposure increased the production of intracellular ROS following OGD/R, while inhibiting ROS production with NAC partially attenuated PM2.5-induced NLRP3 inflammasome activation and pyroptosis under ischemic conditions.ConclusionThese results suggested that PM2.5 exposure triggered the activation of NLRP3 inflammasome and pyroptosis under ischemic conditions, which may be mediated by increased ROS production after ischemic stroke. These findings may provide a more enhanced understanding of the interplay between PM2.5 and neuroinflammation and cell death, and reveal a novel mechanism of PM2.5-mediated toxic effects after ischemic stroke.

Project description:BackgroundToll-like receptor 4 (TLR4) participates in the initiation of neuroinflammation in various neurological diseases, including central nervous system injuries. NLR family pyrin domain containing 3 (NLRP3) inflammasome-mediated microglial pyroptosis is crucial for the inflammatory response during secondary spinal cord injury (SCI). However, the underlying mechanism by which TLR4 regulates NLRP3 inflammasome activation and microglial pyroptosis after SCI remains uncertain.MethodsWe established an in vivo mouse model of SCI using TLR4-knockout (TLR4-KO) and wild-type (WT) mice. The levels of pyroptosis, tissue damage and neurological function recovery were evaluated in the three groups (Sham, SCI, SCI-TLR4-KO). To identify differentially expressed proteins, tandem mass tag (TMT)-based proteomics was conducted using spinal cord tissue between TLR4-KO and WT mice after SCI. For our in vitro model, mouse microglial BV2 cells were exposed to lipopolysaccharides (1 µg/ml, 8 h) and adenosine triphosphate (ATP) (5 mM, 2 h) to induce pyroptosis. A series of molecular biological experiments, including Western blot (WB), real-time quantitative polymerase chain reaction (RT-qPCR), enzyme-linked immunosorbent assay (ELISA), immunofluorescence (IF), immunohistochemical (IHC), chromatin immunoprecipitation (ChIP), Dual-Luciferase Reporter assay (DLA) and co-immunoprecipitation (Co-IP), were performed to explore the specific mechanism of microglial pyroptosis in vivo and in vitro.ResultsOur results indicated that TLR4 promoted the expression of dead-box helicase 3 X-linked (DDX3X), which mediated NLRP3 inflammasome activation and microglial pyroptosis after SCI. Further analysis revealed that TLR4 upregulated the DDX3X/NLRP3 axis by activating the JAK2/STAT1 signalling pathway, and importantly, STAT1 was identified as a transcription factor promoting DDX3X expression. In addition, we found that biglycan was increased after SCI and interacted with TLR4 to jointly regulate microglial pyroptosis through the JAK2/STAT1/DDX3X/NLRP3 axis after SCI.ConclusionOur study preliminarily identified a novel mechanism by which TLR4 regulates NLRP3 inflammasome-mediated microglial pyroptosis in response to SCI-providing a novel and promising therapeutic target for SCI.

Project description:BackgroundAcute respiratory distress syndrome (ARDS) is a common cause of respiratory failure in many critically ill patients. Although inflammasome activation plays an important role in the induction of acute lung injury (ALI) and ARDS, the regulatory mechanism of this process is still unclear. When cells are stimulated by inflammation, the integrity and physiological function of mitochondria play a crucial part in pyroptosis. However, the underlying mechanisms and function of mitochondrial proteins in the process of pyroptosis are largely not yet known. Here, we identified the 18-kDa translocator protein (TSPO), a mitochondrial outer membrane protein, as an important mediator regulating nucleotide-binding domain, leucine-rich repeat, and pyrin domain-containing protein 3 (NLRP3) inflammasome activation in macrophages during ALI.MethodsTSPO gene knockout (KO) and lipopolysaccharide (LPS)-induced ALI/ARDS mouse models were employed to investigate the biological role of TSPO in the pathogenesis of ARDS. Murine macrophages were used to further characterize the effect of TSPO on the NLRP3 inflammasome pathway. Activation of NLRP3 inflammasome was preformed through LPS + adenosine triphosphate (ATP) co-stimulation, followed by detection of mitochondrial membrane potential, reactive oxygen species (ROS) production, and cell death to evaluate the potential biological function of TSPO. Comparisons between two groups were performed with a two-sided unpaired t -test.ResultsTSPO- KO mice exhibited more severe pulmonary inflammation in response to LPS-induced ALI. TSPO deficiency resulted in enhanced activation of the NLRP3 inflammasome pathway, promoting more proinflammatory cytokine production of macrophages in LPS-injured lung tissue, including interleukin (IL)-1β, IL-18, and macrophage inflammatory protein (MIP)-2. Mitochondria in TSPO -KO macrophages tended to depolarize in response to cellular stress. The increased production of mitochondrial damage-associated molecular pattern led to enhanced mitochondrial membrane depolarization and pyroptosis in TSPO -KO cells.ConclusionTSPO may be the key regulator of cellular pyroptosis, and it plays a vital protective role in ARDS occurrence and development.

Dataset Information

Atp13a2 Deficiency Aggravates Astrocyte-Mediated Neuroinflammation via NLRP3 Inflammasome Activation.

Aim

Methods

Results

Conclusions

Publications

Atp13a2 Deficiency Aggravates Astrocyte-Mediated Neuroinflammation via NLRP3 Inflammasome Activation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets