Insects represent emerging sources of bioactive peptides and functional materials.Mantidis Oötheca(Sang-Piao-Xiao in Chinese,SPX)serves as an insect-derived medicine for treating kidney disease.This study demonst...Insects represent emerging sources of bioactive peptides and functional materials.Mantidis Oötheca(Sang-Piao-Xiao in Chinese,SPX)serves as an insect-derived medicine for treating kidney disease.This study demonstrated that supernatant(SPX)improved kidney function in adriamycin(ADR)-induced nephropathy mice model.Transcriptomic analysis revealed that SPX inhibited complement activation by targeting the MASP1-C3/C3a receptor(C3aR)pathway.Peptidomic analysis identified 304 peptides from SPX,with 49 peptides selected for evaluation using prediction tools and molecular docking with complement core protein C3.Three peptides(PMGFPFDR,FNDPK,AAQFFNR)exhibiting docking scores below-8.0 were synthesized to verify complement inhibition and anti-fibrotic activities.The synthetic peptide AAQFFNR demonstrated complement inhibitory activity,with an inhibitory complement hemolytic 50%(ICH_(50))value of 24.54μmol·L^(-1),and exhibited superior protective effects in ADR-induced HK-2 cells.Surface plasmon resonance(SPR)assay revealed direct interaction between AAQFFNR and complement C3 with K_(d)value of 16.8μmol·L^(-1).The reno-protective effect of AAQFFNR was subsequently verified in ADR-induced mice.This research provides initial evidence that complement C3-inhibiting peptides from insects demonstrate potential in preventing nephropathy through in silico and in vivo validation approaches.展开更多
Epilepsy is a brain condition characterized by the recurrence of unprovoked seizures.Recent studies have shown that complement component 3(C3)aggravate the neuronal injury in epilepsy.And our previous studies revealed...Epilepsy is a brain condition characterized by the recurrence of unprovoked seizures.Recent studies have shown that complement component 3(C3)aggravate the neuronal injury in epilepsy.And our previous studies revealed that TRPV1(transient receptor potential vanilloid type 1)is involved in epilepsy.Whether complement C3 regulation of neuronal injury is related to the activation of TRPV1 during epilepsy is not fully understood.We found that in a mouse model of status epilepticus(SE),complement C3 derived from astrocytes was increased and aggravated neuronal injury,and that TRPV 1-knockout rescued neurons from the injury induced by complement C3.Circular RNAs are abundant in the brain,and the reduction of circRad52 caused by complement C3 promoted the expression of TRPV 1 and exacerbated neuronal injury.Mechanistically,disorders of neuron-glia interaction mediated by the C3-TRPV1 signaling pathway may be important for the induction of neuronal injury.This study provides support for the hypothesis that the C3-TRFV1 pathway is involved in the prevention and treatment of neuronal injury and cognitive disorders.展开更多
Objective:Myeloma bone disease(MBD)is the most common complication of multiple myeloma(MM).Our previous study showed that the serum levels of C3/C4 in MM patients were significantly positively correlated with the seve...Objective:Myeloma bone disease(MBD)is the most common complication of multiple myeloma(MM).Our previous study showed that the serum levels of C3/C4 in MM patients were significantly positively correlated with the severity of bone disease.However,the mechanism of C3 a/C4 a in osteoclasts MM patients remains unclear.Methods:The formation and function of osteoclasts were analyzed after adding C3 a/C4 a in vitro.RNA-seq analysis was used to screen the potential pathways affecting osteoclasts,and the results were verified by Western blot,q RT-PCR,and pathway inhibitors.Results:The osteoclast area per view induced by 1μg/m L(mean±SD:50.828±12.984%)and 10μg/m L(53.663±12.685%)of C3 a was significantly increased compared to the control group(0μg/m L)(34.635±8.916%)(P<0.001 and P<0.001,respectively).The relative m RNA expressions of genes,OSCAR/TRAP/RANKL/cathepsin K,induced by 1μg/m L(median:5.041,3.726,1.638,and 4.752,respectively)and 10μg/m L(median:5.140,3.702,2.250,and 5.172,respectively)of C3 a was significantly increased compared to the control group(median:3.137,2.004,0.573,and 2.257,respectively)(1μg/m L P=0.001,P=0.003,P<0.001,and P=0.008,respectively;10μg/m L:P<0.001,P=0.019,P<0.001,and P=0.002,respectively).The absorption areas of the osteoclast resorption pits per view induced by 1μg/m L(mean±SD:51.464±11.983%)and 10μg/m L(50.219±12.067%)of C3 a was also significantly increased(33.845±8.331%)(P<0.001 and P<0.001,respectively)compared to the control.There was no difference between the C4 a and control groups.RNA-seq analysis showed that C3 a promoted the proliferation of osteoclasts using the phosphoinositide 3-kinase(PI3 K)signaling pathway.The relative expressions of PIK3 CA/phosphoinositide dependent kinase-1(PDK1)/serum and glucocorticoid inducible protein kinases(SGK3)genes and PI3 K/PDK1/p-SGK3 protein in the C3 a group were significantly higher than in the control group.The activation role of C3 a in osteoclasts of MM patients was reduced by the SGK inhibitor(EMD638683).Conclusions:C3 a activated osteoclasts by regulating the PI3 K/PDK1/SGK3 pathways in MM patients,which was reduced using a SGK inhibitor.Overall,our results identified potential therapeutic targets and strategies for MBD patients。展开更多
AIM:To evaluate serum complement C4a and its relation to liver fibrosis in children with chronic hepatitis C virus(HCV)infection.METHODS:The study included 30 children with chronic HCV infection before receiving antiv...AIM:To evaluate serum complement C4a and its relation to liver fibrosis in children with chronic hepatitis C virus(HCV)infection.METHODS:The study included 30 children with chronic HCV infection before receiving antiviral therapy.Chronic HCV infection was defined by positive anti-HCV,a positive polymerase chain reaction for HCV-RNA for more than 6 mo with absence of any associated liver disease.A second group of 30 age-and sex-matched healthy children served as controls.Serum C4a levels were measured by enzyme-linked immunosorbent assay.Liver fibrosis stage and inflammatory grade were assessed using Ishak scoring system.Serum C4a levels were compared according to different clinical,laboratory and histopathological parameters.Statistical significance for quantitative data was tested by MannWhitney U non-parametric tests.For qualitative data,significance between groups was tested by 2test.Correlation was tested by Spearman’s test.Results were considered significant if P value≤0.05.RESULTS:The age of the patients ranged from 3.5to 18 years and that of controls ranged from 4 to 17years.C4a mean levels were merely lower in patients(153.67±18.69 mg/L)than that in the controls(157.25±11.40 mg/L)with no statistical significance(P=0.378).It did not differ significantly in patients with elevated vs those with normal transaminases(152.25±16.62 vs 155.36±21.33;P=0.868)or with different HCV viremia(P=0.561).Furthermore,there was no statistical significant difference in serum levels between those with no/mild fibrosis and those with moderate fibrosis(154.65±20.59 vs 152.97±17.72;P=0.786)or minimal and mild activity(155.1±21.93 vs 152.99±17.43;P=0.809).Though statistically not significant,C4a was highest in fibrosis score 0(F0),decreasing in F1 and F2 to be the lowest in F3.When comparing significant fibrosis(Ishak score≥3)vs other stages,C4a was significantly lower in F3 compared to other fibrosis scores(143.55±2.33 mg/L vs 155.26±19.64 mg/L;P=0.047)and at a cutoff value of less than 144.01 mg/L,C4a could discriminate F3 with 76.9%sensitivity and75%specificity from other stages of fibrosis.CONCLUSION:Serum complement C4a did not correlate with any of transaminases,HCV viremia or with the histopathological scores.Although C4a decreased with higher stages of fibrosis,this change was not significant enough to predict individual stages of fibrosis.Yet,it could predict significant fibrosis with acceptable clinical performance.展开更多
A lupus patient with a clinically quiescent disease stage will be described who had severely depressed C4 levels while levels of C3 en CH50 were normal. Additional testing revealed a homozygous C4Aisotype deficiency a...A lupus patient with a clinically quiescent disease stage will be described who had severely depressed C4 levels while levels of C3 en CH50 were normal. Additional testing revealed a homozygous C4Aisotype deficiency as the cause of the very low C4 levels. It should be emphasized that in SLE, a (very) low C4 level does not always means (subclinical) disease activity.展开更多
Objective Xuebijing Injection(XBJI)is mainly used for treating sepsis in China,and even COVID-19 recently.This study aimed to clarify the molecular mechanism(s)and identify the potential“common culprit(s)”for XBJI-c...Objective Xuebijing Injection(XBJI)is mainly used for treating sepsis in China,and even COVID-19 recently.This study aimed to clarify the molecular mechanism(s)and identify the potential“common culprit(s)”for XBJI-caused immediate hypersensitivity reaction(IHR)which is the main type of its adverse reactions.Methods Antiserum against XBJI was prepared by intraperitoneal immunization in combination with aluminum adjuvant for five weeks.Antagonistic experiments were performed by using several antagonists against different mediators in Evans Blue leakage model.Propranolol-pretreated mice were used to determine the capacity of XBJI to trigger systemic IHR.Serum total IgE(tIgE)and mouse mast cell protease 1(MCPT-1)levels,complement activation,and the levels of supernatant inflammatory mediators were determined by ELISAs.Lipopolysaccharide(LPS)-activated RAW264.7 macrophages were used for evaluating the anti-inflammatory activity of XBJI,while human mast cells(LAD2)were used for assessing the effect of XBJI on mast cell degranulation.Results Continuous treatment(i.p.)with XBJI along with aluminum adjuvant did not elevate the levels of serum tIgE and MCPT-1.In vitro,XBJI could not directly cause the degranulation of LAD2 cells.It induced a robust Evans Blue leakage after the first injection in mouse paw.Mechanism study demonstrated that antagonists for histamine H1/H2 receptors and complement C3a receptor counteracted XBJI-induced IHR.XBJI also directly activated complement C3 in human serum.Through screening five herbs of XBJI and the constituents,only safflower yellow(SY)in Carthami Flos was able to induce IHR.The discolored-XBJI not only did not induce IHR locally and systemically,but also could suppressing the production of proinflammatory mediators in LPS-activated RAW264.7 macrophages.Conclusion XBJI failed to induce immune IHR,but potently triggered non-immune IHR through direct activating complement C3 to provoke histamine release.SY in Carthami Flos was the underlying“common culprit”responsible for XBJI-caused IHR.The anti-inflammatory action of XBJI can be retained after decolorization.Our study provides a scientific basis for not only preventing and treating XBJI-caused IHR clinically,but also improving its production process.展开更多
Activation of spinal cord neural stem cells(NSCs)and subsequent neurogenesis holds a promising alternative for spinal cord injury(SCI)repair.Our previous study demonstrated that complement C3a,derived from reactive as...Activation of spinal cord neural stem cells(NSCs)and subsequent neurogenesis holds a promising alternative for spinal cord injury(SCI)repair.Our previous study demonstrated that complement C3a,derived from reactive astrocytes,inhibits NSC proliferation by suppressing protein aggregate clearance through the deubiquitinating enzyme ubiquitin carboxy-terminal hydrolase L1(UCHL1)-proteasome system post-SCI.However,the potential molecular mechanism by which C3a modulates NSC activation via this pathway remains unclear.Here,we revealed that C3a/C3a receptor(C3aR)signaling activated NF-κB p65,which in turn inhibited Nrf2 activity and UCHL1 expression,resulting in diminished proteasome activity and the accumulation of protein aggregates,and ultimately impaired NSC activation.Both knockdown of NF-κB p65 and Nrf2 upregulation restored UCHL1 expression and proteasome activity in vitro,promoting NSC activation by enhancing protein aggregate clearance.Mechanistically,we found that NF-κB p65 regulated Nrf2 activity through a dual mechanism:(1)promoting Keap1-dependent ubiquitination and proteasome degradation of Nrf2;(2)inhibiting protein kinase C-mediated Nrf2 phosphorylation and nuclear translocation.Using the dual-luciferase reporter assay and chromatin immunoprecipitation(ChIP)analysis,we further identified UCHL1 as a direct transcriptional target of Nrf2.Importantly,in vivo experiments using SCI mice confirmed that either C3aR blockade,NF-κB p65 knockdown,or Nrf2 overexpression could rescue SCI-induced UCHL1 downregulation.Together,this study uncovers the C3a-NF-κB p65-Nrf2-UCHL1-proteasome axis as a critical regulator of NSC activation after SCI.This may provide novel molecular targets and intervention strategies for SCI repair.展开更多
[Objective] This study aimed to clone C4B gene in Siji goose and detect its expression level in different tissues. [Method] cDNA sequence of C4B gene was cloned with RACE-PCR method. Amino acid sequences in multiple s...[Objective] This study aimed to clone C4B gene in Siji goose and detect its expression level in different tissues. [Method] cDNA sequence of C4B gene was cloned with RACE-PCR method. Amino acid sequences in multiple species were aligned in GenBank, and a phylogenetic tree was constructed for homology analysis. [Result] C4B gene in Siji goose shared relatively high homology with chicken and quail; Siji goose C4B gene was expressed highly in liver and lung of adult geese and expressed lowly in epididymis, seminiferous duct, brain, kidney, testis, heart, oviduct and smal intestine. [Conclusion] In the present study, mRNA expression lev-el of C4B gene in different tissues and organs of Siji goose was determined by flu-orescence quantitative PCR, which provided basis for rapid diagnosis of specific an-imal diseases.展开更多
基金supported by the National Natural Science Foundation of China(No.82104353)China Postdoctoral Science Foundation funded project(No.2022M711680).
文摘Insects represent emerging sources of bioactive peptides and functional materials.Mantidis Oötheca(Sang-Piao-Xiao in Chinese,SPX)serves as an insect-derived medicine for treating kidney disease.This study demonstrated that supernatant(SPX)improved kidney function in adriamycin(ADR)-induced nephropathy mice model.Transcriptomic analysis revealed that SPX inhibited complement activation by targeting the MASP1-C3/C3a receptor(C3aR)pathway.Peptidomic analysis identified 304 peptides from SPX,with 49 peptides selected for evaluation using prediction tools and molecular docking with complement core protein C3.Three peptides(PMGFPFDR,FNDPK,AAQFFNR)exhibiting docking scores below-8.0 were synthesized to verify complement inhibition and anti-fibrotic activities.The synthetic peptide AAQFFNR demonstrated complement inhibitory activity,with an inhibitory complement hemolytic 50%(ICH_(50))value of 24.54μmol·L^(-1),and exhibited superior protective effects in ADR-induced HK-2 cells.Surface plasmon resonance(SPR)assay revealed direct interaction between AAQFFNR and complement C3 with K_(d)value of 16.8μmol·L^(-1).The reno-protective effect of AAQFFNR was subsequently verified in ADR-induced mice.This research provides initial evidence that complement C3-inhibiting peptides from insects demonstrate potential in preventing nephropathy through in silico and in vivo validation approaches.
基金by the National Natural Science Foundation of China(81571481 and 82060588)the Natural Science Foundation of Hubei Province,China(2017CFA017)+1 种基金the Wuhan Science and Technology Project(2019020701011444)the Medical Science Advancement Program of Wuhan University(TFJC2018001 and TFLC2018001).
文摘Epilepsy is a brain condition characterized by the recurrence of unprovoked seizures.Recent studies have shown that complement component 3(C3)aggravate the neuronal injury in epilepsy.And our previous studies revealed that TRPV1(transient receptor potential vanilloid type 1)is involved in epilepsy.Whether complement C3 regulation of neuronal injury is related to the activation of TRPV1 during epilepsy is not fully understood.We found that in a mouse model of status epilepticus(SE),complement C3 derived from astrocytes was increased and aggravated neuronal injury,and that TRPV 1-knockout rescued neurons from the injury induced by complement C3.Circular RNAs are abundant in the brain,and the reduction of circRad52 caused by complement C3 promoted the expression of TRPV 1 and exacerbated neuronal injury.Mechanistically,disorders of neuron-glia interaction mediated by the C3-TRPV1 signaling pathway may be important for the induction of neuronal injury.This study provides support for the hypothesis that the C3-TRFV1 pathway is involved in the prevention and treatment of neuronal injury and cognitive disorders.
基金supported by the National Natural Science Foundation of China(Grant Nos.81770110,81900131,and 82000219)the Anticancer Major Special Project of Tianjin(Grant No.12ZCDZSY18000)+4 种基金the Tianjin Municipal Natural Science Foundation(Grant Nos.18JCYBJC27200 and 18JCQNJC80400)the Tianjin Education Commission Research Project(Grant Nos.2018KJ043 and 2018KJ045)the Tianjin Health and Family Planning Commission(Grant No.15KG150)the Youth Incubation Fund of Tianjin Medical University General Hospital(Grant No.ZYYFY2019020)the Tianjin Science and Technology Planning Project(Grant No.20YFZCSY00060)。
文摘Objective:Myeloma bone disease(MBD)is the most common complication of multiple myeloma(MM).Our previous study showed that the serum levels of C3/C4 in MM patients were significantly positively correlated with the severity of bone disease.However,the mechanism of C3 a/C4 a in osteoclasts MM patients remains unclear.Methods:The formation and function of osteoclasts were analyzed after adding C3 a/C4 a in vitro.RNA-seq analysis was used to screen the potential pathways affecting osteoclasts,and the results were verified by Western blot,q RT-PCR,and pathway inhibitors.Results:The osteoclast area per view induced by 1μg/m L(mean±SD:50.828±12.984%)and 10μg/m L(53.663±12.685%)of C3 a was significantly increased compared to the control group(0μg/m L)(34.635±8.916%)(P<0.001 and P<0.001,respectively).The relative m RNA expressions of genes,OSCAR/TRAP/RANKL/cathepsin K,induced by 1μg/m L(median:5.041,3.726,1.638,and 4.752,respectively)and 10μg/m L(median:5.140,3.702,2.250,and 5.172,respectively)of C3 a was significantly increased compared to the control group(median:3.137,2.004,0.573,and 2.257,respectively)(1μg/m L P=0.001,P=0.003,P<0.001,and P=0.008,respectively;10μg/m L:P<0.001,P=0.019,P<0.001,and P=0.002,respectively).The absorption areas of the osteoclast resorption pits per view induced by 1μg/m L(mean±SD:51.464±11.983%)and 10μg/m L(50.219±12.067%)of C3 a was also significantly increased(33.845±8.331%)(P<0.001 and P<0.001,respectively)compared to the control.There was no difference between the C4 a and control groups.RNA-seq analysis showed that C3 a promoted the proliferation of osteoclasts using the phosphoinositide 3-kinase(PI3 K)signaling pathway.The relative expressions of PIK3 CA/phosphoinositide dependent kinase-1(PDK1)/serum and glucocorticoid inducible protein kinases(SGK3)genes and PI3 K/PDK1/p-SGK3 protein in the C3 a group were significantly higher than in the control group.The activation role of C3 a in osteoclasts of MM patients was reduced by the SGK inhibitor(EMD638683).Conclusions:C3 a activated osteoclasts by regulating the PI3 K/PDK1/SGK3 pathways in MM patients,which was reduced using a SGK inhibitor.Overall,our results identified potential therapeutic targets and strategies for MBD patients。
基金Supported by National Liver Institute,Menofiya University,Egypt
文摘AIM:To evaluate serum complement C4a and its relation to liver fibrosis in children with chronic hepatitis C virus(HCV)infection.METHODS:The study included 30 children with chronic HCV infection before receiving antiviral therapy.Chronic HCV infection was defined by positive anti-HCV,a positive polymerase chain reaction for HCV-RNA for more than 6 mo with absence of any associated liver disease.A second group of 30 age-and sex-matched healthy children served as controls.Serum C4a levels were measured by enzyme-linked immunosorbent assay.Liver fibrosis stage and inflammatory grade were assessed using Ishak scoring system.Serum C4a levels were compared according to different clinical,laboratory and histopathological parameters.Statistical significance for quantitative data was tested by MannWhitney U non-parametric tests.For qualitative data,significance between groups was tested by 2test.Correlation was tested by Spearman’s test.Results were considered significant if P value≤0.05.RESULTS:The age of the patients ranged from 3.5to 18 years and that of controls ranged from 4 to 17years.C4a mean levels were merely lower in patients(153.67±18.69 mg/L)than that in the controls(157.25±11.40 mg/L)with no statistical significance(P=0.378).It did not differ significantly in patients with elevated vs those with normal transaminases(152.25±16.62 vs 155.36±21.33;P=0.868)or with different HCV viremia(P=0.561).Furthermore,there was no statistical significant difference in serum levels between those with no/mild fibrosis and those with moderate fibrosis(154.65±20.59 vs 152.97±17.72;P=0.786)or minimal and mild activity(155.1±21.93 vs 152.99±17.43;P=0.809).Though statistically not significant,C4a was highest in fibrosis score 0(F0),decreasing in F1 and F2 to be the lowest in F3.When comparing significant fibrosis(Ishak score≥3)vs other stages,C4a was significantly lower in F3 compared to other fibrosis scores(143.55±2.33 mg/L vs 155.26±19.64 mg/L;P=0.047)and at a cutoff value of less than 144.01 mg/L,C4a could discriminate F3 with 76.9%sensitivity and75%specificity from other stages of fibrosis.CONCLUSION:Serum complement C4a did not correlate with any of transaminases,HCV viremia or with the histopathological scores.Although C4a decreased with higher stages of fibrosis,this change was not significant enough to predict individual stages of fibrosis.Yet,it could predict significant fibrosis with acceptable clinical performance.
文摘A lupus patient with a clinically quiescent disease stage will be described who had severely depressed C4 levels while levels of C3 en CH50 were normal. Additional testing revealed a homozygous C4Aisotype deficiency as the cause of the very low C4 levels. It should be emphasized that in SLE, a (very) low C4 level does not always means (subclinical) disease activity.
基金supported by CAMS Innovation Fund for Medical Sciences(CIFMS)(No.2021-I2M-1-028 and No.2021-I2M-1-031)National Natural Science Foundation of China(No.82074091)Beijing Natural Science Foundation(No.M21014).
文摘Objective Xuebijing Injection(XBJI)is mainly used for treating sepsis in China,and even COVID-19 recently.This study aimed to clarify the molecular mechanism(s)and identify the potential“common culprit(s)”for XBJI-caused immediate hypersensitivity reaction(IHR)which is the main type of its adverse reactions.Methods Antiserum against XBJI was prepared by intraperitoneal immunization in combination with aluminum adjuvant for five weeks.Antagonistic experiments were performed by using several antagonists against different mediators in Evans Blue leakage model.Propranolol-pretreated mice were used to determine the capacity of XBJI to trigger systemic IHR.Serum total IgE(tIgE)and mouse mast cell protease 1(MCPT-1)levels,complement activation,and the levels of supernatant inflammatory mediators were determined by ELISAs.Lipopolysaccharide(LPS)-activated RAW264.7 macrophages were used for evaluating the anti-inflammatory activity of XBJI,while human mast cells(LAD2)were used for assessing the effect of XBJI on mast cell degranulation.Results Continuous treatment(i.p.)with XBJI along with aluminum adjuvant did not elevate the levels of serum tIgE and MCPT-1.In vitro,XBJI could not directly cause the degranulation of LAD2 cells.It induced a robust Evans Blue leakage after the first injection in mouse paw.Mechanism study demonstrated that antagonists for histamine H1/H2 receptors and complement C3a receptor counteracted XBJI-induced IHR.XBJI also directly activated complement C3 in human serum.Through screening five herbs of XBJI and the constituents,only safflower yellow(SY)in Carthami Flos was able to induce IHR.The discolored-XBJI not only did not induce IHR locally and systemically,but also could suppressing the production of proinflammatory mediators in LPS-activated RAW264.7 macrophages.Conclusion XBJI failed to induce immune IHR,but potently triggered non-immune IHR through direct activating complement C3 to provoke histamine release.SY in Carthami Flos was the underlying“common culprit”responsible for XBJI-caused IHR.The anti-inflammatory action of XBJI can be retained after decolorization.Our study provides a scientific basis for not only preventing and treating XBJI-caused IHR clinically,but also improving its production process.
基金supported by the National Natural Science Foundation of China(82071362 and 82270669)Key Project of the Regional Joint Fund of Guangdong Province(2023B1515120077)+3 种基金Basic Research Program of Shenzhen Science and Technology Innovation Commission(JCYJ20210324123001003 and JCYJ20220530144801003)Shenzhen Key Laboratory of Bone Tissue Repair and Translational Research(ZDSYS20230626091402006)the Innovation and Entrepreneurship Training Program for College Students,Sun Yat-sen University(20242150)the Leading Innovation and Entrepreneurship Team Program of Zhejiang Province,China(2023R01005).
文摘Activation of spinal cord neural stem cells(NSCs)and subsequent neurogenesis holds a promising alternative for spinal cord injury(SCI)repair.Our previous study demonstrated that complement C3a,derived from reactive astrocytes,inhibits NSC proliferation by suppressing protein aggregate clearance through the deubiquitinating enzyme ubiquitin carboxy-terminal hydrolase L1(UCHL1)-proteasome system post-SCI.However,the potential molecular mechanism by which C3a modulates NSC activation via this pathway remains unclear.Here,we revealed that C3a/C3a receptor(C3aR)signaling activated NF-κB p65,which in turn inhibited Nrf2 activity and UCHL1 expression,resulting in diminished proteasome activity and the accumulation of protein aggregates,and ultimately impaired NSC activation.Both knockdown of NF-κB p65 and Nrf2 upregulation restored UCHL1 expression and proteasome activity in vitro,promoting NSC activation by enhancing protein aggregate clearance.Mechanistically,we found that NF-κB p65 regulated Nrf2 activity through a dual mechanism:(1)promoting Keap1-dependent ubiquitination and proteasome degradation of Nrf2;(2)inhibiting protein kinase C-mediated Nrf2 phosphorylation and nuclear translocation.Using the dual-luciferase reporter assay and chromatin immunoprecipitation(ChIP)analysis,we further identified UCHL1 as a direct transcriptional target of Nrf2.Importantly,in vivo experiments using SCI mice confirmed that either C3aR blockade,NF-κB p65 knockdown,or Nrf2 overexpression could rescue SCI-induced UCHL1 downregulation.Together,this study uncovers the C3a-NF-κB p65-Nrf2-UCHL1-proteasome axis as a critical regulator of NSC activation after SCI.This may provide novel molecular targets and intervention strategies for SCI repair.
基金Supported by Agricultural Independent Innovation Fund of Jiangsu Province[CX(09)638]~~
文摘[Objective] This study aimed to clone C4B gene in Siji goose and detect its expression level in different tissues. [Method] cDNA sequence of C4B gene was cloned with RACE-PCR method. Amino acid sequences in multiple species were aligned in GenBank, and a phylogenetic tree was constructed for homology analysis. [Result] C4B gene in Siji goose shared relatively high homology with chicken and quail; Siji goose C4B gene was expressed highly in liver and lung of adult geese and expressed lowly in epididymis, seminiferous duct, brain, kidney, testis, heart, oviduct and smal intestine. [Conclusion] In the present study, mRNA expression lev-el of C4B gene in different tissues and organs of Siji goose was determined by flu-orescence quantitative PCR, which provided basis for rapid diagnosis of specific an-imal diseases.
