Background:Neutrophils are traditionally viewed as first responders but have a short onset of action in response to traumatic brain injury(TBI).However,the heterogeneity,multifunctionality,and time-dependent modulatio...Background:Neutrophils are traditionally viewed as first responders but have a short onset of action in response to traumatic brain injury(TBI).However,the heterogeneity,multifunctionality,and time-dependent modulation of brain damage and outcome mediated by neutrophils after TBI remain poorly understood.Methods:Using the combined single-cell transcriptomics,metabolomics,and proteomics analysis from TBI patients and the TBI mouse model,we investigate a novel neutrophil phenotype and its associated effects on TBI outcome by neurological deficit scoring and behavioral tests.We also characterized the underlying mechanisms both invitro and invivo through molecular simulations,signaling detections,gene expression regulation assessments[including dual-luciferase reporter and chromatin immunoprecipitation(ChIP)assays],primary cultures or co-cultures of neutrophils and oligodendrocytes,intracellular iron,and lipid hydroperoxide concentration measurements,as well as forkhead box protein O1(FOXO1)conditional knockout mice.Results:We identified that high expression of the FOXO1 protein was induced in neutrophils after TBI both in TBI patients and the TBI mouse model.Infiltration of these FOXO1high neutrophils in the brain was detected not only in the acute phase but also in the chronic phase post-TBI,aggravating acute brain inflammatory damage and promoting late TBI-induced depression.In the acute stage,FOXO1 upregulated cytoplasmic Versican(VCAN)to interact with the apoptosis regulator B-cell lymphoma-2(BCL-2)-associated X protein(BAX),suppressing the mitochondrial translocation of BAX,which mediated the antiapoptotic effect companied with enhancing interleukin-6(IL-6)production of FOXO1high neutrophils.In the chronic stage,the“FOXO1-transferrin receptor(TFRC)”mechanism contributes to FOXO1high neutrophil ferroptosis,disturbing the iron homeostasis of oligodendrocytes and inducing a reduction in myelin basic protein,which contributes to the progression of late depression after TBI.Conclusions:FOXO1high neutrophils represent a novel neutrophil phenotype that emerges in response to acute and chronic TBI,which provides insight into the heterogeneity,reprogramming activity,and versatility of neutrophils in TBI.展开更多
Objective Proprionibacterium acnes(P.acnes)-induced inflammatory responses,proliferation and differentiation of keratinocytes contribute to the progression of acne vulgaris(AV).P.acnes was found to enhance the product...Objective Proprionibacterium acnes(P.acnes)-induced inflammatory responses,proliferation and differentiation of keratinocytes contribute to the progression of acne vulgaris(AV).P.acnes was found to enhance the production of interleukin-8(IL-8)by keratinocytes.This study aimed to investigate the role of IL-8 in P.acnes-induced proliferation and differentiation of keratinocytes and the underlying mechanism.Methods The P.acnes-stimulated HaCaT cell(a human keratinocyte cell line)model was established.Western blotting and immunofluorescence were performed to detect the expression of the IL-8 receptors C-X-C motif chemokine receptor 1(CXCR1)and C-X-C motif chemokine receptor 2(CXCR2)on HaCaT cells.Cell counting kit-8(CCK-8)assay,5-ethynyl-20-deoxyuridine(EdU)assay and Western blotting were performed to examine the effects of IL-8/CXCR2 axis on the proliferation and differentiation of HaCaT cells treated with P.acnes,the IL-8 neutralizing antibody,the CXCR2 antagonist(SB225002),or the CXCR1/CXCR2 antagonist(G31P).Western blotting,nuclear and cytoplasmic separation,CCK-8 assay,and EdU assay were employed to determine the downstream pathway of CXCR2 after P.acnes-stimulated HaCaT cells were treated with the CXCR2 antagonist,the protein kinase B(AKT)antagonist(AZD5363),or the constitutively active forkhead box O1(FOXO1)mutant.Finally,autophagy markers were measured in HaCaT cells following the transfection of the FOXO1 mutant or treatment with the autophagy inhibitor 3-methyladenine(3-MA).Results The expression levels of CXCR1 and CXCR2 were significantly increased on the membrane of HaCaT cells following P.acnes stimulation.The IL-8/CXCR2 axis predominantly promoted the proliferation and differentiation of P.acnes-induced HaCaT cells by activating AKT/FOXO1/autophagy signaling.In brief,IL-8 bound to its receptor CXCR2 on the membrane of keratinocytes to activate the AKT/FOXO1 axis.Subsequently,phosphorylated FOXO1 facilitated autophagy to promote the proliferation and differentiation of P.acnes-induced keratinocytes.Conclusion This study demonstrated the novel autocrine effect of IL-8 on the proliferation and differentiation of P.acnes-induced keratinocytes,suggesting a potential therapeutic target for AV.展开更多
高原低氧环境会引起肌力下降和运动能力退化,而抗阻训练是刺激骨骼肌生长的重要手段,叉头转录因子1(fork head box protein O 1,FoxO1)在调控骨骼肌蛋白质分解通路中承担重要角色。为探究Akt-FoxO1通路是否参与抗阻训练抑制低氧诱导的...高原低氧环境会引起肌力下降和运动能力退化,而抗阻训练是刺激骨骼肌生长的重要手段,叉头转录因子1(fork head box protein O 1,FoxO1)在调控骨骼肌蛋白质分解通路中承担重要角色。为探究Akt-FoxO1通路是否参与抗阻训练抑制低氧诱导的骨骼肌萎缩,本研究构建低氧诱导骨骼肌萎缩的大鼠模型,并模拟海拔4 000 m低氧环境下(12.4%O_2)进行抗阻训练,对比观察大鼠比目鱼肌和趾长伸肌湿重和横截面积,以及蛋白激酶B(protein kinase B,Akt)、叉头转录因子1、泛素蛋白连接酶1(muscle ring finger 1,MuRF1)的表达差异等。结果表明,低氧暴露导致大鼠趾长伸肌湿重显著下降,苏木精-伊红染色组织切片分析肌纤维横截面积、低氧环境下比目鱼肌横截面积明显下降,而低氧抗阻训练后趾长伸肌横截面积明显高于安静组。实时荧光定量PCR和蛋白质免疫印迹结果显示,低氧暴露后FoxO1和MuRF1基因表达明显上调,低氧下抗阻训练后发现,Akt基因表达明显上调而FoxO1、MuRF则明显下调。免疫荧光观察磷酸化FoxO1在细胞核内外表达情况,发现抗阻训练后FoxO1(S256)于细胞核外表达增强。上述结果表明,抗阻训练可以达到抑制低氧诱导骨骼肌萎缩的效果,Akt促进FoxO1磷酸化从而减缓骨骼肌蛋白质分解过程是抗阻训练能够抑制骨骼肌萎缩的分子机制之一。展开更多
基金This work was supported by the National Natural Science Foundation of China(82071779 and 81901626)the Science Fund for Creative Research Groups of Chongqing Municipal Education Commission of China,the grants from the Talent Foundation of Army Medical University(to Shuang-Shuang Dai)+1 种基金the Scientific Research Grant(ALJ22J003)the Chongqing Natural Science Foundation of China(CSTB2022NSCQ-MSX0177).
文摘Background:Neutrophils are traditionally viewed as first responders but have a short onset of action in response to traumatic brain injury(TBI).However,the heterogeneity,multifunctionality,and time-dependent modulation of brain damage and outcome mediated by neutrophils after TBI remain poorly understood.Methods:Using the combined single-cell transcriptomics,metabolomics,and proteomics analysis from TBI patients and the TBI mouse model,we investigate a novel neutrophil phenotype and its associated effects on TBI outcome by neurological deficit scoring and behavioral tests.We also characterized the underlying mechanisms both invitro and invivo through molecular simulations,signaling detections,gene expression regulation assessments[including dual-luciferase reporter and chromatin immunoprecipitation(ChIP)assays],primary cultures or co-cultures of neutrophils and oligodendrocytes,intracellular iron,and lipid hydroperoxide concentration measurements,as well as forkhead box protein O1(FOXO1)conditional knockout mice.Results:We identified that high expression of the FOXO1 protein was induced in neutrophils after TBI both in TBI patients and the TBI mouse model.Infiltration of these FOXO1high neutrophils in the brain was detected not only in the acute phase but also in the chronic phase post-TBI,aggravating acute brain inflammatory damage and promoting late TBI-induced depression.In the acute stage,FOXO1 upregulated cytoplasmic Versican(VCAN)to interact with the apoptosis regulator B-cell lymphoma-2(BCL-2)-associated X protein(BAX),suppressing the mitochondrial translocation of BAX,which mediated the antiapoptotic effect companied with enhancing interleukin-6(IL-6)production of FOXO1high neutrophils.In the chronic stage,the“FOXO1-transferrin receptor(TFRC)”mechanism contributes to FOXO1high neutrophil ferroptosis,disturbing the iron homeostasis of oligodendrocytes and inducing a reduction in myelin basic protein,which contributes to the progression of late depression after TBI.Conclusions:FOXO1high neutrophils represent a novel neutrophil phenotype that emerges in response to acute and chronic TBI,which provides insight into the heterogeneity,reprogramming activity,and versatility of neutrophils in TBI.
基金supported by the National Natural Science Foundation of China(No.82103756).
文摘Objective Proprionibacterium acnes(P.acnes)-induced inflammatory responses,proliferation and differentiation of keratinocytes contribute to the progression of acne vulgaris(AV).P.acnes was found to enhance the production of interleukin-8(IL-8)by keratinocytes.This study aimed to investigate the role of IL-8 in P.acnes-induced proliferation and differentiation of keratinocytes and the underlying mechanism.Methods The P.acnes-stimulated HaCaT cell(a human keratinocyte cell line)model was established.Western blotting and immunofluorescence were performed to detect the expression of the IL-8 receptors C-X-C motif chemokine receptor 1(CXCR1)and C-X-C motif chemokine receptor 2(CXCR2)on HaCaT cells.Cell counting kit-8(CCK-8)assay,5-ethynyl-20-deoxyuridine(EdU)assay and Western blotting were performed to examine the effects of IL-8/CXCR2 axis on the proliferation and differentiation of HaCaT cells treated with P.acnes,the IL-8 neutralizing antibody,the CXCR2 antagonist(SB225002),or the CXCR1/CXCR2 antagonist(G31P).Western blotting,nuclear and cytoplasmic separation,CCK-8 assay,and EdU assay were employed to determine the downstream pathway of CXCR2 after P.acnes-stimulated HaCaT cells were treated with the CXCR2 antagonist,the protein kinase B(AKT)antagonist(AZD5363),or the constitutively active forkhead box O1(FOXO1)mutant.Finally,autophagy markers were measured in HaCaT cells following the transfection of the FOXO1 mutant or treatment with the autophagy inhibitor 3-methyladenine(3-MA).Results The expression levels of CXCR1 and CXCR2 were significantly increased on the membrane of HaCaT cells following P.acnes stimulation.The IL-8/CXCR2 axis predominantly promoted the proliferation and differentiation of P.acnes-induced HaCaT cells by activating AKT/FOXO1/autophagy signaling.In brief,IL-8 bound to its receptor CXCR2 on the membrane of keratinocytes to activate the AKT/FOXO1 axis.Subsequently,phosphorylated FOXO1 facilitated autophagy to promote the proliferation and differentiation of P.acnes-induced keratinocytes.Conclusion This study demonstrated the novel autocrine effect of IL-8 on the proliferation and differentiation of P.acnes-induced keratinocytes,suggesting a potential therapeutic target for AV.
基金supported by the National High-Tech R&D Program of China(“863”Program)(2009AA22704)the National Natural Science Foundation of China(30873089,81173129)+3 种基金the Program for Changjiang Scholars and Innovative Research Team in University(IRT0946)the Open Foundation of Innovative Platform in University of Hunan Province of China(10K078)the Science and Technology Plan Key Grant of Hunan Province of China(2009TP40682)the Fundamental Research Funds for the Central Universities(201023100001)
文摘目的:在细胞水平研究烟酰胺单核苷酸(nicotinamide mononucleotide,NMN)对胰岛素分泌的调节作用及其对与胰岛素分泌相关的重要转录因子胰十二指肠同源盒基因(pancreatic and duodenalhomeobox-1,PDX-1)和分叉头框家族转录因子1(forkhead box-containing protein O-1,FoxO1)基因表达的影响。方法:采用大鼠胰岛素ELISA试剂盒检测RIN-m5f细胞胰岛素分泌水平。用Real-time PCR检测RIN-m5f细胞PDX-1和FoxO1的mRNA表达水平。用Western印迹检测RIN-m5f细胞PDX-1蛋白表达水平。结果:用瑞格列奈10 nmol/L+NMN 100μmol/L处理RIN-m5f细胞48 h,与空白对照及DMSO对照组相比,胰岛素分泌量均显著增高(P<0.05);与NMN 50μmol/L组比较,胰岛素分泌量的增高也有统计学意义(P<0.05)。10,50和100μmol/L的NMN作用RIN-m5f细胞36 h,PDX-1的mRNA表达量均上调(依次为P<0.05,P<0.01,P<0.001)。100μmol/L剂量组与10μmol/L和50μmol/L剂量组比较差异也有统计学意义(P<0.001)。50,100和200μmol/L的NMN作用RIN-m5f细胞36或48 h,PDX-1的蛋白表达量与对照组比较差异无统计学意义(P>0.05)。结论:NMN可以调控RIN-m5f细胞中胰岛素的分泌及PDX-1的mRNA表达水平。
文摘高原低氧环境会引起肌力下降和运动能力退化,而抗阻训练是刺激骨骼肌生长的重要手段,叉头转录因子1(fork head box protein O 1,FoxO1)在调控骨骼肌蛋白质分解通路中承担重要角色。为探究Akt-FoxO1通路是否参与抗阻训练抑制低氧诱导的骨骼肌萎缩,本研究构建低氧诱导骨骼肌萎缩的大鼠模型,并模拟海拔4 000 m低氧环境下(12.4%O_2)进行抗阻训练,对比观察大鼠比目鱼肌和趾长伸肌湿重和横截面积,以及蛋白激酶B(protein kinase B,Akt)、叉头转录因子1、泛素蛋白连接酶1(muscle ring finger 1,MuRF1)的表达差异等。结果表明,低氧暴露导致大鼠趾长伸肌湿重显著下降,苏木精-伊红染色组织切片分析肌纤维横截面积、低氧环境下比目鱼肌横截面积明显下降,而低氧抗阻训练后趾长伸肌横截面积明显高于安静组。实时荧光定量PCR和蛋白质免疫印迹结果显示,低氧暴露后FoxO1和MuRF1基因表达明显上调,低氧下抗阻训练后发现,Akt基因表达明显上调而FoxO1、MuRF则明显下调。免疫荧光观察磷酸化FoxO1在细胞核内外表达情况,发现抗阻训练后FoxO1(S256)于细胞核外表达增强。上述结果表明,抗阻训练可以达到抑制低氧诱导骨骼肌萎缩的效果,Akt促进FoxO1磷酸化从而减缓骨骼肌蛋白质分解过程是抗阻训练能够抑制骨骼肌萎缩的分子机制之一。
