背景:NOD样受体热蛋白结构域相关蛋白3(NOD-like receptor thermal protein domain associated protein 3,NLRP3)炎性小体与脊髓损伤后的神经炎症密切相关,小胶质细胞极化和焦亡在其中发挥关键作用,靶向调控NLRP3有利于诱导小胶质细胞...背景:NOD样受体热蛋白结构域相关蛋白3(NOD-like receptor thermal protein domain associated protein 3,NLRP3)炎性小体与脊髓损伤后的神经炎症密切相关,小胶质细胞极化和焦亡在其中发挥关键作用,靶向调控NLRP3有利于诱导小胶质细胞从M1促炎表型向M2抗炎表型极化和调节小胶质细胞焦亡,是一个有前景的治疗策略。目的:归纳NLRP3炎性小体在脊髓损伤后小胶质细胞中作用的分子机制以及治疗策略的研究进展。方法:检索PubMed、Web of Science和中国知网数据库,英文检索词为“spinal cord injury,NLRP3,microglia,polarization,pyroptosis”,中文检索词为“脊髓损伤,NLRP3,小胶质细胞,极化,焦亡,炎症”,按纳入和排除标准共纳入79篇文献进行总结。结果与结论:①目前,关于脊髓损伤复杂的发病机制尚未有统一定论,大量研究表明脊髓损伤与炎症因子和信号通路关系密切,以NLRP3炎性小体作为其发病机制和治疗突破口的相关研究也是当前的热点。②NLRP3炎性小体在脊髓损伤后的炎症反应、氧化应激和神经元恢复等起到关键作用。③小胶质细胞是脑和脊髓中的免疫细胞,是继发性脊髓损伤最重要的调节因子,脊髓损伤后小胶质细胞对内部环境作出调整,主要表现为极化及焦亡,产生大量炎症因子,阻碍脊髓损伤的神经再生和功能恢复,通过调控小胶质细胞表型变化,是治疗脊髓损伤的另一个关键因素。④NLRP3炎性小体与小胶质细胞密切相关,脊髓损伤后NLRP3炎性小体主要在小胶质细胞中表达,其会促进小胶质细胞向M1极化和促进促裂解蛋白D的产生,进一步破坏神经稳态,从而加重脊髓损伤的进展。⑤许多分子参与NLRP3炎性小体调控小胶质细胞,其中核转录因子κB及MAPK信号通路促进NLRP3炎性小体表达,其他信号通路抑制该炎性小体表达。⑥目前有大量的外源性分子及药物调控NLRP3炎性小体,临床应用前景广泛,已有相关药物处于临床试验阶段并取得良好疗效,如NLRP3特异性抑制剂MCC950,但如何精准控制靶向递送、减少对其他组织器官影响等关键问题亟需解决,随着研究的深入,未来有望在脊髓损伤治疗方式上作出新的突破。展开更多
Alzheimer's disease is characterized by deposition of amyloid-β,which forms extracellular neuritic plaques,and accumulation of hyperphosphorylated tau,which aggregates to form intraneuronal neurofibrillary tangle...Alzheimer's disease is characterized by deposition of amyloid-β,which forms extracellular neuritic plaques,and accumulation of hyperphosphorylated tau,which aggregates to form intraneuronal neurofibrillary tangles,in the brain.The NLRP3 inflammasome may play a role in the transition from amyloid-βdeposition to tau phosphorylation and aggregation.Because NLRP3 is primarily found in brain microglia,and tau is predominantly located in neurons,it has been suggested that NLRP3 expressed by microglia indirectly triggers tau phosphorylation by upregulating the expression of pro-inflammatory cytokines.Here,we found that neurons also express NLRP3 in vitro and in vivo,and that neuronal NLRP3 regulates tau phosphorylation.Using biochemical methods,we mapped the minimal NLRP3 promoter and identified FUBP3 as a transcription factor regulating NLRP3 expression in neurons.In primary neurons and the neuroblastoma cell line Neuro2A,FUBP3 is required for endogenous NLRP3 expression and tau phosphorylation only when amyloid-βis present.In the brains of aged wild-type mice and a mouse model of Alzheimer's disease,FUBP3 expression was markedly increased in cortical neurons.Transcriptome analysis suggested that FUBP3 plays a role in neuron-mediated immune responses.We also found that FUBP3 trimmed the 5′end of DNA fragments that it bound,implying that FUBP3 functions in stress-induced responses.These findings suggest that neuronal NLRP3 may be more directly involved in the amyloid-β-to–phospho-tau transition than microglial NLRP3,and that amyloid-βfundamentally alters the regulatory mechanism of NLRP3 expression in neurons.Given that FUBP3 was only expressed at low levels in young wild-type mice and was strongly upregulated in the brains of aged mice and Alzheimer's disease mice,FUBP3 could be a safe therapeutic target for preventing Alzheimer's disease progression.展开更多
Noise-induced hearing loss is the primary non-genetic factor contributing to auditory dysfunction.However,there are currently no effective pharmacological interventions for patients with noise-induced hearing loss.Her...Noise-induced hearing loss is the primary non-genetic factor contributing to auditory dysfunction.However,there are currently no effective pharmacological interventions for patients with noise-induced hearing loss.Here,we present evidence suggesting that the lysine-specific demethylase 1 inhibitor–tranylcypromine is an otoprotective agent that could be used to treat noise-induced hearing loss,and elucidate its underlying regulatory mechanisms.We established a mouse model of permanent threshold shift hearing loss by exposing the mice to white broadband noise at a sound pressure level of 120 d B for 4 hours.We found that tranylcypromine treatment led to the upregulation of Sestrin2(SESN2)and activation of the autophagy markers light chain 3B and lysosome-associated membrane glycoprotein 1 in the cochleae of mice treated with tranylcypromine.The noise exposure group treated with tranylcypromine showed significantly lower average auditory brainstem response hearing thresholds at click,4,8,and 16 k Hz frequencies compared with the noise exposure group treated with saline.These findings indicate that tranylcypromine treatment resulted in increased SESN2,light chain 3B,and lysosome-associated membrane glycoprotein 1 expression after noise exposure,leading to a reduction in levels of 4-hydroxynonenal and cleaved caspase-3,thereby reducing noise-induced hair cell loss.Additionally,immunoblot analysis demonstrated that treatment with tranylcypromine upregulated SESN2 expression via the autophagy pathway.Tranylcypromine treatment also reduced the production of NOD-like receptor family pyrin domaincontaining 3(NLRP3)production.In conclusion,our results showed that tranylcypromine treatment ameliorated cochlear inflammation by promoting the expression of SESN2,which induced autophagy,thereby restricting NLRP3-related inflammasome signaling,alleviating cochlear hair cell loss,and protecting hearing function.These findings suggest that inhibiting lysine-specific demethylase 1 is a potential therapeutic strategy for preventing hair cell loss and noise-induced hearing loss.展开更多
Our previous studies have reported that activation of the NLRP3(NOD-,LRR-and pyrin domain-containing protein 3)-inflammasome complex in ethanol-treated astrocytes and chronic alcohol-fed mice could be associated with ...Our previous studies have reported that activation of the NLRP3(NOD-,LRR-and pyrin domain-containing protein 3)-inflammasome complex in ethanol-treated astrocytes and chronic alcohol-fed mice could be associated with neuroinflammation and brain damage.Mesenchymal stem cell-derived extracellular vesicles(MSC-EVs)have been shown to restore the neuroinflammatory response,along with myelin and synaptic structural alterations in the prefrontal cortex,and alleviate cognitive and memory dysfunctions induced by binge-like ethanol treatment in adolescent mice.Considering the therapeutic role of the molecules contained in mesenchymal stem cell-derived extracellular vesicles,the present study analyzed whether the administration of mesenchymal stem cell-derived extracellular vesicles isolated from adipose tissue,which inhibited the activation of the NLRP3 inflammasome,was capable of reducing hippocampal neuroinflammation in adolescent mice treated with binge drinking.We demonstrated that the administration of mesenchymal stem cell-derived extracellular vesicles ameliorated the activation of the hippocampal NLRP3 inflammasome complex and other NLRs inflammasomes(e.g.,pyrin domain-containing 1,caspase recruitment domain-containing 4,and absent in melanoma 2,as well as the alterations in inflammatory genes(interleukin-1β,interleukin-18,inducible nitric oxide synthase,nuclear factor-kappa B,monocyte chemoattractant protein-1,and C–X3–C motif chemokine ligand 1)and miRNAs(miR-21a-5p,miR-146a-5p,and miR-141-5p)induced by binge-like ethanol treatment in adolescent mice.Bioinformatic analysis further revealed the involvement of miR-21a-5p and miR-146a-5p with inflammatory target genes and NOD-like receptor signaling pathways.Taken together,these findings provide novel evidence of the therapeutic potential of MSC-derived EVs to ameliorate the hippocampal neuroinflammatory response associated with NLRP3 inflammasome activation induced by binge drinking in adolescence.展开更多
Aminoglycosides are a widely used class of antibacterials renowned for their effectiveness and broad antimicrobial spectrum.However,their use leads to irreversible hearing damage by causing apoptosis of hair cells as ...Aminoglycosides are a widely used class of antibacterials renowned for their effectiveness and broad antimicrobial spectrum.However,their use leads to irreversible hearing damage by causing apoptosis of hair cells as their direct target.In addition,the hearing damage caused by aminoglycosides involves damage of spiral ganglion neurons upon exposure.To investigate the mechanisms underlying spiral ganglion neuron degeneration induced by aminoglycosides,we used a C57BL/6J mouse model treated with kanamycin.We found that the mice exhibited auditory deficits following the acute loss of outer hair cells.Spiral ganglion neurons displayed hallmarks of pyroptosis and exhibited progressive degeneration over time.Transcriptomic profiling of these neurons showed significant upregulation of genes associated with inflammation and immune response,particularly those related to the NLRP3 inflammasome.Activation of the canonical pyroptotic pathway in spiral ganglion neurons was observed,accompanied by infiltration of macrophages and the release of proinflammatory cytokines.Pharmacological intervention targeting NLRP3 using Mcc950 and genetic intervention using NLRP3 knockout ameliorated spiral ganglion neuron degeneration in the injury model.These findings suggest that NLRP3 inflammasome-mediated pyroptosis plays a role in aminoglycoside-induced spiral ganglion neuron degeneration.Inhibition of this pathway may offer a potential therapeutic strategy for treating sensorineural hearing loss by reducing spiral ganglion neuron degeneration.展开更多
Neurotoxic astrocytes are a promising therapeutic target for the attenuation of cerebral ischemia/reperfusion injury.Low-density lipoprotein receptor,a classic cholesterol regulatory receptor,has been found to inhibit...Neurotoxic astrocytes are a promising therapeutic target for the attenuation of cerebral ischemia/reperfusion injury.Low-density lipoprotein receptor,a classic cholesterol regulatory receptor,has been found to inhibit NLR family pyrin domain containing protein 3(NLRP3)inflammasome activation in neurons following ischemic stroke and to suppress the activation of microglia and astrocytes in individuals with Alzheimer’s disease.However,little is known about the effects of low-density lipoprotein receptor on astrocytic activation in ischemic stroke.To address this issue in the present study,we examined the mechanisms by which low-density lipoprotein receptor regulates astrocytic polarization in ischemic stroke models.First,we examined low-density lipoprotein receptor expression in astrocytes via immunofluorescence staining and western blotting analysis.We observed significant downregulation of low-density lipoprotein receptor following middle cerebral artery occlusion reperfusion and oxygen-glucose deprivation/reoxygenation.Second,we induced the astrocyte-specific overexpression of low-density lipoprotein receptor using astrocyte-specific adeno-associated virus.Low-density lipoprotein receptor overexpression in astrocytes improved neurological outcomes in middle cerebral artery occlusion mice and reversed neurotoxic astrocytes to create a neuroprotective phenotype.Finally,we found that the overexpression of low-density lipoprotein receptor inhibited NLRP3 inflammasome activation in oxygen-glucose deprivation/reoxygenation injured astrocytes and that the addition of nigericin,an NLRP3 agonist,restored the neurotoxic astrocyte phenotype.These findings suggest that low-density lipoprotein receptor could inhibit the NLRP3-meidiated neurotoxic polarization of astrocytes and that increasing low-density lipoprotein receptor in astrocytes might represent a novel strategy for treating cerebral ischemic stroke.展开更多
文摘背景:NOD样受体热蛋白结构域相关蛋白3(NOD-like receptor thermal protein domain associated protein 3,NLRP3)炎性小体与脊髓损伤后的神经炎症密切相关,小胶质细胞极化和焦亡在其中发挥关键作用,靶向调控NLRP3有利于诱导小胶质细胞从M1促炎表型向M2抗炎表型极化和调节小胶质细胞焦亡,是一个有前景的治疗策略。目的:归纳NLRP3炎性小体在脊髓损伤后小胶质细胞中作用的分子机制以及治疗策略的研究进展。方法:检索PubMed、Web of Science和中国知网数据库,英文检索词为“spinal cord injury,NLRP3,microglia,polarization,pyroptosis”,中文检索词为“脊髓损伤,NLRP3,小胶质细胞,极化,焦亡,炎症”,按纳入和排除标准共纳入79篇文献进行总结。结果与结论:①目前,关于脊髓损伤复杂的发病机制尚未有统一定论,大量研究表明脊髓损伤与炎症因子和信号通路关系密切,以NLRP3炎性小体作为其发病机制和治疗突破口的相关研究也是当前的热点。②NLRP3炎性小体在脊髓损伤后的炎症反应、氧化应激和神经元恢复等起到关键作用。③小胶质细胞是脑和脊髓中的免疫细胞,是继发性脊髓损伤最重要的调节因子,脊髓损伤后小胶质细胞对内部环境作出调整,主要表现为极化及焦亡,产生大量炎症因子,阻碍脊髓损伤的神经再生和功能恢复,通过调控小胶质细胞表型变化,是治疗脊髓损伤的另一个关键因素。④NLRP3炎性小体与小胶质细胞密切相关,脊髓损伤后NLRP3炎性小体主要在小胶质细胞中表达,其会促进小胶质细胞向M1极化和促进促裂解蛋白D的产生,进一步破坏神经稳态,从而加重脊髓损伤的进展。⑤许多分子参与NLRP3炎性小体调控小胶质细胞,其中核转录因子κB及MAPK信号通路促进NLRP3炎性小体表达,其他信号通路抑制该炎性小体表达。⑥目前有大量的外源性分子及药物调控NLRP3炎性小体,临床应用前景广泛,已有相关药物处于临床试验阶段并取得良好疗效,如NLRP3特异性抑制剂MCC950,但如何精准控制靶向递送、减少对其他组织器官影响等关键问题亟需解决,随着研究的深入,未来有望在脊髓损伤治疗方式上作出新的突破。
基金supported by a grant from Key Laboratory of Alzheimer's Disease of Zhejiang Province,Institute of Aging,Wenzhou Medical University,No.ZJAD-2021002(to ZW)。
文摘Alzheimer's disease is characterized by deposition of amyloid-β,which forms extracellular neuritic plaques,and accumulation of hyperphosphorylated tau,which aggregates to form intraneuronal neurofibrillary tangles,in the brain.The NLRP3 inflammasome may play a role in the transition from amyloid-βdeposition to tau phosphorylation and aggregation.Because NLRP3 is primarily found in brain microglia,and tau is predominantly located in neurons,it has been suggested that NLRP3 expressed by microglia indirectly triggers tau phosphorylation by upregulating the expression of pro-inflammatory cytokines.Here,we found that neurons also express NLRP3 in vitro and in vivo,and that neuronal NLRP3 regulates tau phosphorylation.Using biochemical methods,we mapped the minimal NLRP3 promoter and identified FUBP3 as a transcription factor regulating NLRP3 expression in neurons.In primary neurons and the neuroblastoma cell line Neuro2A,FUBP3 is required for endogenous NLRP3 expression and tau phosphorylation only when amyloid-βis present.In the brains of aged wild-type mice and a mouse model of Alzheimer's disease,FUBP3 expression was markedly increased in cortical neurons.Transcriptome analysis suggested that FUBP3 plays a role in neuron-mediated immune responses.We also found that FUBP3 trimmed the 5′end of DNA fragments that it bound,implying that FUBP3 functions in stress-induced responses.These findings suggest that neuronal NLRP3 may be more directly involved in the amyloid-β-to–phospho-tau transition than microglial NLRP3,and that amyloid-βfundamentally alters the regulatory mechanism of NLRP3 expression in neurons.Given that FUBP3 was only expressed at low levels in young wild-type mice and was strongly upregulated in the brains of aged mice and Alzheimer's disease mice,FUBP3 could be a safe therapeutic target for preventing Alzheimer's disease progression.
基金supported by the National Key Research and Development Program of China,No.2022YFC2402701(to WC)Key International(Regional)Joint Research Program of the National Natural Science Foundation of China,No.81820108009(to SY)+5 种基金the National Natural Science Foundation of China,Nos.81970890(to WC)and 82371148(to WG)Fujian Provincial Healthcare Young and Middle-aged Backbone Talent Training Project,No.2023GGA035(to XC)Spring City Planthe High-level Talent Promotion and Training Project of Kunming,No.2022SCP001(to SY)the Natural Science Foundation of Hainan Province of China,No.824MS052(to XS)the Sixth Medical Center of Chinese PLA General Hospital Innovation Cultivation,No.CXPY202116(to LX)。
文摘Noise-induced hearing loss is the primary non-genetic factor contributing to auditory dysfunction.However,there are currently no effective pharmacological interventions for patients with noise-induced hearing loss.Here,we present evidence suggesting that the lysine-specific demethylase 1 inhibitor–tranylcypromine is an otoprotective agent that could be used to treat noise-induced hearing loss,and elucidate its underlying regulatory mechanisms.We established a mouse model of permanent threshold shift hearing loss by exposing the mice to white broadband noise at a sound pressure level of 120 d B for 4 hours.We found that tranylcypromine treatment led to the upregulation of Sestrin2(SESN2)and activation of the autophagy markers light chain 3B and lysosome-associated membrane glycoprotein 1 in the cochleae of mice treated with tranylcypromine.The noise exposure group treated with tranylcypromine showed significantly lower average auditory brainstem response hearing thresholds at click,4,8,and 16 k Hz frequencies compared with the noise exposure group treated with saline.These findings indicate that tranylcypromine treatment resulted in increased SESN2,light chain 3B,and lysosome-associated membrane glycoprotein 1 expression after noise exposure,leading to a reduction in levels of 4-hydroxynonenal and cleaved caspase-3,thereby reducing noise-induced hair cell loss.Additionally,immunoblot analysis demonstrated that treatment with tranylcypromine upregulated SESN2 expression via the autophagy pathway.Tranylcypromine treatment also reduced the production of NOD-like receptor family pyrin domaincontaining 3(NLRP3)production.In conclusion,our results showed that tranylcypromine treatment ameliorated cochlear inflammation by promoting the expression of SESN2,which induced autophagy,thereby restricting NLRP3-related inflammasome signaling,alleviating cochlear hair cell loss,and protecting hearing function.These findings suggest that inhibiting lysine-specific demethylase 1 is a potential therapeutic strategy for preventing hair cell loss and noise-induced hearing loss.
基金supported by grants from the Spanish Ministry of Health-PNSD(2019-I039 and 2023-I024)(to MP)FEDER/Ministerio de Ciencia e Innovación-Agencia Estatal de Investigación PID2021-1243590B-I100(to VMM)+2 种基金GVA(CIAICO/2021/203)(to MP)the Primary Addiction Care Research Network(RD21/0009/0005)(to MP)a predoctoral fellowship from the Generalitat Valenciana(ACIF/2021/338)(to CPC).
文摘Our previous studies have reported that activation of the NLRP3(NOD-,LRR-and pyrin domain-containing protein 3)-inflammasome complex in ethanol-treated astrocytes and chronic alcohol-fed mice could be associated with neuroinflammation and brain damage.Mesenchymal stem cell-derived extracellular vesicles(MSC-EVs)have been shown to restore the neuroinflammatory response,along with myelin and synaptic structural alterations in the prefrontal cortex,and alleviate cognitive and memory dysfunctions induced by binge-like ethanol treatment in adolescent mice.Considering the therapeutic role of the molecules contained in mesenchymal stem cell-derived extracellular vesicles,the present study analyzed whether the administration of mesenchymal stem cell-derived extracellular vesicles isolated from adipose tissue,which inhibited the activation of the NLRP3 inflammasome,was capable of reducing hippocampal neuroinflammation in adolescent mice treated with binge drinking.We demonstrated that the administration of mesenchymal stem cell-derived extracellular vesicles ameliorated the activation of the hippocampal NLRP3 inflammasome complex and other NLRs inflammasomes(e.g.,pyrin domain-containing 1,caspase recruitment domain-containing 4,and absent in melanoma 2,as well as the alterations in inflammatory genes(interleukin-1β,interleukin-18,inducible nitric oxide synthase,nuclear factor-kappa B,monocyte chemoattractant protein-1,and C–X3–C motif chemokine ligand 1)and miRNAs(miR-21a-5p,miR-146a-5p,and miR-141-5p)induced by binge-like ethanol treatment in adolescent mice.Bioinformatic analysis further revealed the involvement of miR-21a-5p and miR-146a-5p with inflammatory target genes and NOD-like receptor signaling pathways.Taken together,these findings provide novel evidence of the therapeutic potential of MSC-derived EVs to ameliorate the hippocampal neuroinflammatory response associated with NLRP3 inflammasome activation induced by binge drinking in adolescence.
基金supported by the National Natural Science Foundation of China,Nos.81800919(to YX),82171140(to PW)the International Cooperation and Exchange of the National Natural Science Foundation of China,Nos.82020108008(to HS),81720108010(to SY).
文摘Aminoglycosides are a widely used class of antibacterials renowned for their effectiveness and broad antimicrobial spectrum.However,their use leads to irreversible hearing damage by causing apoptosis of hair cells as their direct target.In addition,the hearing damage caused by aminoglycosides involves damage of spiral ganglion neurons upon exposure.To investigate the mechanisms underlying spiral ganglion neuron degeneration induced by aminoglycosides,we used a C57BL/6J mouse model treated with kanamycin.We found that the mice exhibited auditory deficits following the acute loss of outer hair cells.Spiral ganglion neurons displayed hallmarks of pyroptosis and exhibited progressive degeneration over time.Transcriptomic profiling of these neurons showed significant upregulation of genes associated with inflammation and immune response,particularly those related to the NLRP3 inflammasome.Activation of the canonical pyroptotic pathway in spiral ganglion neurons was observed,accompanied by infiltration of macrophages and the release of proinflammatory cytokines.Pharmacological intervention targeting NLRP3 using Mcc950 and genetic intervention using NLRP3 knockout ameliorated spiral ganglion neuron degeneration in the injury model.These findings suggest that NLRP3 inflammasome-mediated pyroptosis plays a role in aminoglycoside-induced spiral ganglion neuron degeneration.Inhibition of this pathway may offer a potential therapeutic strategy for treating sensorineural hearing loss by reducing spiral ganglion neuron degeneration.
基金supported by the National Natural Science Foundation of China,No.82201460(to YH)Nanjing Medical University Science and Technology Development Fund,No.NMUB20210202(to YH).
文摘Neurotoxic astrocytes are a promising therapeutic target for the attenuation of cerebral ischemia/reperfusion injury.Low-density lipoprotein receptor,a classic cholesterol regulatory receptor,has been found to inhibit NLR family pyrin domain containing protein 3(NLRP3)inflammasome activation in neurons following ischemic stroke and to suppress the activation of microglia and astrocytes in individuals with Alzheimer’s disease.However,little is known about the effects of low-density lipoprotein receptor on astrocytic activation in ischemic stroke.To address this issue in the present study,we examined the mechanisms by which low-density lipoprotein receptor regulates astrocytic polarization in ischemic stroke models.First,we examined low-density lipoprotein receptor expression in astrocytes via immunofluorescence staining and western blotting analysis.We observed significant downregulation of low-density lipoprotein receptor following middle cerebral artery occlusion reperfusion and oxygen-glucose deprivation/reoxygenation.Second,we induced the astrocyte-specific overexpression of low-density lipoprotein receptor using astrocyte-specific adeno-associated virus.Low-density lipoprotein receptor overexpression in astrocytes improved neurological outcomes in middle cerebral artery occlusion mice and reversed neurotoxic astrocytes to create a neuroprotective phenotype.Finally,we found that the overexpression of low-density lipoprotein receptor inhibited NLRP3 inflammasome activation in oxygen-glucose deprivation/reoxygenation injured astrocytes and that the addition of nigericin,an NLRP3 agonist,restored the neurotoxic astrocyte phenotype.These findings suggest that low-density lipoprotein receptor could inhibit the NLRP3-meidiated neurotoxic polarization of astrocytes and that increasing low-density lipoprotein receptor in astrocytes might represent a novel strategy for treating cerebral ischemic stroke.
