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
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
BACKGROUND Complement-mediated thrombotic microangiopathy(TMA)is a rare endothelial injury syndrome caused by dysregulated activation of the alternative complement pathway,often linked to genetic abnormalities in comp...BACKGROUND Complement-mediated thrombotic microangiopathy(TMA)is a rare endothelial injury syndrome caused by dysregulated activation of the alternative complement pathway,often linked to genetic abnormalities in complement factor H(CFH),complement factor I,or complement factor H-related(CFHR)proteins.Both renal transplantation and pregnancy are independent triggers for recurrence.This case highlights a genetically high-risk patient who achieved a successful term pregnancy after renal transplantation without complement inhibition,emphasizing individualized risk stratification,close surveillance,and multidisciplinary management for favourable maternal and graft outcomes.CASE SUMMARY A 32-year-old woman with end-stage renal disease secondary to genetically confirmed complement-mediated TMA—homozygous CFH exon 17 deletion and CFHR3-CFHR1 duplication—was maintained on dialysis for 2.5 years before undergoing a successful live-donor kidney transplant from her mother.Post-transplant immunosuppression included tacrolimus,mycophenolate mofetil,and prednisolone,later modified to azathioprine during pregnancy planning.One-year post-transplant,she conceived spontaneously.Pregnancy was complicated by transient gestational hypertension,controlled with nifedipine,labetalol,and amlodipine.Proteinuria remained<150 mg/day;white blood cell counts 5.8-7.2×109/L without cytopenia.Serum creatinine ranged 0.9-1.1 mg/dL,and tacrolimus trough levels 5-7 ng/mL.At 36 weeks,she delivered a healthy 3 kg infant by elective caesarean section.Postpartum follow-up at three months confirmed stable maternal and graft function.CONCLUSION High-risk complement-mediated TMA patients can achieve successful pregnancy post-transplant through individualized care without mandatory complement blockade.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.
文摘BACKGROUND Complement-mediated thrombotic microangiopathy(TMA)is a rare endothelial injury syndrome caused by dysregulated activation of the alternative complement pathway,often linked to genetic abnormalities in complement factor H(CFH),complement factor I,or complement factor H-related(CFHR)proteins.Both renal transplantation and pregnancy are independent triggers for recurrence.This case highlights a genetically high-risk patient who achieved a successful term pregnancy after renal transplantation without complement inhibition,emphasizing individualized risk stratification,close surveillance,and multidisciplinary management for favourable maternal and graft outcomes.CASE SUMMARY A 32-year-old woman with end-stage renal disease secondary to genetically confirmed complement-mediated TMA—homozygous CFH exon 17 deletion and CFHR3-CFHR1 duplication—was maintained on dialysis for 2.5 years before undergoing a successful live-donor kidney transplant from her mother.Post-transplant immunosuppression included tacrolimus,mycophenolate mofetil,and prednisolone,later modified to azathioprine during pregnancy planning.One-year post-transplant,she conceived spontaneously.Pregnancy was complicated by transient gestational hypertension,controlled with nifedipine,labetalol,and amlodipine.Proteinuria remained<150 mg/day;white blood cell counts 5.8-7.2×109/L without cytopenia.Serum creatinine ranged 0.9-1.1 mg/dL,and tacrolimus trough levels 5-7 ng/mL.At 36 weeks,she delivered a healthy 3 kg infant by elective caesarean section.Postpartum follow-up at three months confirmed stable maternal and graft function.CONCLUSION High-risk complement-mediated TMA patients can achieve successful pregnancy post-transplant through individualized care without mandatory complement blockade.
