Muscle atrophy can be induced by high doses or prolonged use of glucocorticoids.Kaempferol(Kae)is a naturally occurring flavonoid with a variety of biological activities and the effect of Kae on dexamethasone(Dex)indu...Muscle atrophy can be induced by high doses or prolonged use of glucocorticoids.Kaempferol(Kae)is a naturally occurring flavonoid with a variety of biological activities and the effect of Kae on dexamethasone(Dex)induced muscle atrophy in animals has not been elucidated.To explore this issue,the present experiments used a computationally assisted drug design scheme combining network pharmacology,molecular docking and in vivo experiments to investigate the mechanism of Kae against muscle atrophy.Network pharmacological analyses revealed 275 potential targets for Kae and 12294 potential targets for muscle atrophy,with a total of 228 crosstargets for Kae and muscle atrophy.GO and KEGG analyses were performed based on the protein-protein interaction(PPI)network of muscle atrophy and Kae component targets.The GO results showed that the biological processes were mainly related to the metabolic process of reactive oxygen species,and the response to oxidative stress;the cellular components were mainly focused on membrane microdomains,and membrane regions;the molecular functions mainly worked on phosphatase binding;and the KEGG pathway enrichment analyses identified the pathways of interaction between Kae and muscle atrophy.Finally,as verified by in vivo experiments,Kae may reduce the onset of muscle atrophy by activating the PI3K/AKT/m TOR/signalling pathway,inhibiting Foxo1/Foxo3 activity,and inhibiting downstream production of the ubiquitination 3 ligases Atrogin1 and Mu RF1;Kae also promotes the expression of NRF2/HO-1/KEAP1 signalling pathway,enhances muscle antioxidant capacity,inhibits the release of COX-2 and TNF-αinflammatory factors,and reduces the damage caused by oxidative stress and inflammatory factors to muscles.Therefore,there may be a synergistic effect of PI3K/AKT/m TOR and NRF2/HO-1/KEAP1 in Kae working together to prevent muscle atrophy.The binding energy and stability of Kae to potential targets were examined by molecular docking and molecular dynamics simulations,implying that Kae could be used for the prevention and treatment of muscle atrophy in patients.展开更多
Ultraviolet A(UVA)radiation accelerates skin photoaging through oxidative stress and extracellular matrix(ECM)degradation.Salmon leather-derived collagen peptides(SLCP),rich in glycine-proline(Gly-Pro)motifs,emerge as...Ultraviolet A(UVA)radiation accelerates skin photoaging through oxidative stress and extracellular matrix(ECM)degradation.Salmon leather-derived collagen peptides(SLCP),rich in glycine-proline(Gly-Pro)motifs,emerge as sustainable marine-derived bioactive agents with uncharacterized photoprotective mechanisms.The study aimed to investigate the protective effects of SLCP against UVA-induced photoaging in human skin fibroblasts(HSF)and elucidate the underlying molecular mechanisms,particularly those involving the Nrf2/Keap1 pathway.SLCP demonstrated no cytotoxicity across tested concentrations(50-200μg/mL).In UVA-exposed HSF,SLCP significantly attenuated ROS generation(by 39.84-55.09%)and MDA accumulation(to 0.66-0.81 nmol/mg protein),while restoring SOD and CAT activities to near-basal levels.Additionally,SLCP downregulated MMP-9 and MMP-12 expression by 39.72-73.02%,attenuated ECM degradation,and restored elastin content to 3.71-13.21%of control levels.Mechanistically,SLCP inhibited Nrf2/Keap1 pathway activation,thereby downregulating HO-1,GCLC,and GCLM expression in a dose-dependent manner.Notably,SLCP exerted minimal influence on collagen synthesis-related genes(COL1A1,COL3A1).Collectively,these results indicate that SLCP mitigate UVA-induced photoaging through a dual mechanism that fortifies antioxidant defenses and safeguards extracellular-matrix integrity through precise modulation of the Nrf2/Keap1 pathway.This positions SLCP as naturally derived,mechanism-specific anti-aging agents and provides a compelling scientific basis for valorizing salmon processing by-products.展开更多
Background:Myocardial infarction(MI)remains a major global public health challenge.Although advances in reperfusion therapy have reduced acute mortality,post-infarction cardiac remodeling continues to pose a substanti...Background:Myocardial infarction(MI)remains a major global public health challenge.Although advances in reperfusion therapy have reduced acute mortality,post-infarction cardiac remodeling continues to pose a substantial threat to long-term cardiovascular health.Oxidative stress and the ensuing inflammatory response are key drivers of this pathological process,leading to cardiomyocyte death,myocardial fibrosis,and functional impairment.Among the regulatory pathways involved,the kelch-like ECH-associated protein 1(Keap1)/nuclear factor erythroid 2-related factor 2(Nrf2)axis has emerged as a critical therapeutic target for mitigating post-MI cardiac injury.Methods:A murine MI model was established by permanent ligation of the left anterior descending coronary artery.Mice received oral Tongxinbi formula(TXB)at low,medium,or high doses(9/18/36 g/kg)once daily for 28 days.Cardiac function was assessed by echocardiography;myocardial fibrosis by Masson’s trichrome;and endothelial integrity by CD31 immunofluorescence.Plasma markers of endothelial function and inflammation were quantified.In vitro,oxidative stress was induced by H2O2 in vascular endothelial cells and cardiomyocytes,followed by treatment with TXB drug-containing serum.Western blot and RT-qPCR were used to measure components of the Keap1/Nrf2 pathway;ELISA quantified oxidative stress and inflammatory indices.Conditioned-medium experiments evaluated endothelial cell–mediated paracrine protection of cardiomyocytes.Results:TXB significantly improved cardiac function and reduced myocardial fibrosis after MI,in association with preservation of microvascular structure and systemic attenuation of oxidative stress and inflammation.In vitro,TXB activated the endothelial Keap1/Nrf2 pathway,enhanced cellular antioxidant defenses,increased VEGF secretion,and,via endothelial cell-mediated paracrine signaling,alleviated cardiomyocyte injury under oxidative stress.Conclusion:TXB exerts anti-fibrotic and cardioprotective effects by activating Nrf2 signaling and engaging endothelial-mediated paracrine mechanisms,collectively mitigating oxidative stress and inflammation in the post-MI setting.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:Dry eye disease(DED)predominantly results from elevated tear film os-molarity,which can not only cause ocular inconvenience but may lead to visual impair-ments,severely compromising patient well-being and e...Background:Dry eye disease(DED)predominantly results from elevated tear film os-molarity,which can not only cause ocular inconvenience but may lead to visual impair-ments,severely compromising patient well-being and exerting substantial economic burdens as well.Astaxanthin(AST),a member of the xanthophylls and recognized for its robust abilities to combat inflammation and oxidation,is a common dietary sup-plement.Nonetheless,the precise molecular pathways through which AST influences DED are still poorly understood.Methods:Therapeutic targets for AST were identified using data from the GeneCards,PharmMapper,and Swiss Target Prediction databases,and STITCH datasets.Similarly,targets for dry eye disease(DED)were delineated leveraging resources such as the Therapeutic Target Database(TTD),DisGeNET,GeneCards,and OMIM databases,and DrugBank datasets.Interactions among shared targets were charted and dis-played using CytoScape 3.9.0.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were conducted to elucidate the functions of pivotal tar-gets within the protein-protein interaction network.Molecular interactions between AST and key targets were confirmed through molecular docking using AutoDock and PyMOL.Molecular dynamics simulations were performed using GROMACS 2022.3.Viability of human corneal epithelial cells(hCEC)was assessed across varying concen-trations of AST.A mouse model of experimental DED was developed using 0.1%ben-zalkonium chloride(BAC),and the animals were administered 100 mg/kg/day of AST orally for 7 days.The efficacy of the treatments was assessed through a series of di-agnostic tests to evaluate the condition of the ocular surface after the interventions.The levels of inflammation and oxidative stress were quantitatively assessed using methods such as reverse transcription-polymerase chain reaction(RT-PCR),Western blot,and immunofluorescence staining.Results:Network pharmacology suggests that AST may alleviate DED by influenc-ing oxidation-reduction signaling pathways and reducing oxidative stress provoked by BAC.In vivo experiments demonstrated an improved overall condition in AST-administered mice in contrast to the control group.Immunofluorescence staining analyses indicated a decrease in Keap1 protein in the corneal tissues of AST-treated mice and a significant increase in Nrf2 and HO-1 protein.In vitro studies demon-strated that AST significantly enhanced cell viability and suppressed reactive oxy-gen species expression under hyperosmotic(HS)conditions,thereby protecting the human corneal epithelium.Conclusion:AST is capable of shielding mice from BAC-induced DED,decelerating the progression of DED,and mitigating oxidative stress damage under HS conditions in hCEC cells.The protective impact of AST on DED may operate through stimulating the Keap1-Nrf2/HO-1 signaling pathway.Our research findings indicate that AST may be a promising treatment for DED,offering new insights into DED treatment.展开更多
基金funded by Yunnan Youth Top-notch Talent Support Program(YNWR-QNBJ2018-173)Agricultural Joint project of Yunnan Provincial S&T Programs(202301BD070001-195)+2 种基金S&T project of Yunnan provincial finance(K212020001-01)supported by Yunnan Province Education Department’s Engineering Research Center of Eco-friendly Products from Yunnan Characteristic Edible FungiYunnan Province Yongsheng County Farmer Academician Technology service station.
文摘Muscle atrophy can be induced by high doses or prolonged use of glucocorticoids.Kaempferol(Kae)is a naturally occurring flavonoid with a variety of biological activities and the effect of Kae on dexamethasone(Dex)induced muscle atrophy in animals has not been elucidated.To explore this issue,the present experiments used a computationally assisted drug design scheme combining network pharmacology,molecular docking and in vivo experiments to investigate the mechanism of Kae against muscle atrophy.Network pharmacological analyses revealed 275 potential targets for Kae and 12294 potential targets for muscle atrophy,with a total of 228 crosstargets for Kae and muscle atrophy.GO and KEGG analyses were performed based on the protein-protein interaction(PPI)network of muscle atrophy and Kae component targets.The GO results showed that the biological processes were mainly related to the metabolic process of reactive oxygen species,and the response to oxidative stress;the cellular components were mainly focused on membrane microdomains,and membrane regions;the molecular functions mainly worked on phosphatase binding;and the KEGG pathway enrichment analyses identified the pathways of interaction between Kae and muscle atrophy.Finally,as verified by in vivo experiments,Kae may reduce the onset of muscle atrophy by activating the PI3K/AKT/m TOR/signalling pathway,inhibiting Foxo1/Foxo3 activity,and inhibiting downstream production of the ubiquitination 3 ligases Atrogin1 and Mu RF1;Kae also promotes the expression of NRF2/HO-1/KEAP1 signalling pathway,enhances muscle antioxidant capacity,inhibits the release of COX-2 and TNF-αinflammatory factors,and reduces the damage caused by oxidative stress and inflammatory factors to muscles.Therefore,there may be a synergistic effect of PI3K/AKT/m TOR and NRF2/HO-1/KEAP1 in Kae working together to prevent muscle atrophy.The binding energy and stability of Kae to potential targets were examined by molecular docking and molecular dynamics simulations,implying that Kae could be used for the prevention and treatment of muscle atrophy in patients.
基金supported by the Dalian High-level Innovative Talent Team Project(2023RG005)Xingliao Talent Program(XLYC2403202)the Open Project of Engineering Research Center of Dairy Quality and Safety Control Technology,Ministry of Education(RK202302).
文摘Ultraviolet A(UVA)radiation accelerates skin photoaging through oxidative stress and extracellular matrix(ECM)degradation.Salmon leather-derived collagen peptides(SLCP),rich in glycine-proline(Gly-Pro)motifs,emerge as sustainable marine-derived bioactive agents with uncharacterized photoprotective mechanisms.The study aimed to investigate the protective effects of SLCP against UVA-induced photoaging in human skin fibroblasts(HSF)and elucidate the underlying molecular mechanisms,particularly those involving the Nrf2/Keap1 pathway.SLCP demonstrated no cytotoxicity across tested concentrations(50-200μg/mL).In UVA-exposed HSF,SLCP significantly attenuated ROS generation(by 39.84-55.09%)and MDA accumulation(to 0.66-0.81 nmol/mg protein),while restoring SOD and CAT activities to near-basal levels.Additionally,SLCP downregulated MMP-9 and MMP-12 expression by 39.72-73.02%,attenuated ECM degradation,and restored elastin content to 3.71-13.21%of control levels.Mechanistically,SLCP inhibited Nrf2/Keap1 pathway activation,thereby downregulating HO-1,GCLC,and GCLM expression in a dose-dependent manner.Notably,SLCP exerted minimal influence on collagen synthesis-related genes(COL1A1,COL3A1).Collectively,these results indicate that SLCP mitigate UVA-induced photoaging through a dual mechanism that fortifies antioxidant defenses and safeguards extracellular-matrix integrity through precise modulation of the Nrf2/Keap1 pathway.This positions SLCP as naturally derived,mechanism-specific anti-aging agents and provides a compelling scientific basis for valorizing salmon processing by-products.
基金the Major Special Project of Jiangsu Administration of Traditional Chinese Medicine(Project No.ZT202116)the Key R&D Project of Jiangsu Province(Project No.BE2020727)+2 种基金the Yangzhou Science and Technology Program(Project No.YZ2021062,YZ2024143 and YZ2024194)the Third Batch of Academic Mentorship Program for Senior TCM Experts in Jiangsu Province(Project No.2019028)the 2023 Jiangsu Pharmaceutical Association–Aosaikang Hospital Pharmacy Research Project(Project No.A202333).
文摘Background:Myocardial infarction(MI)remains a major global public health challenge.Although advances in reperfusion therapy have reduced acute mortality,post-infarction cardiac remodeling continues to pose a substantial threat to long-term cardiovascular health.Oxidative stress and the ensuing inflammatory response are key drivers of this pathological process,leading to cardiomyocyte death,myocardial fibrosis,and functional impairment.Among the regulatory pathways involved,the kelch-like ECH-associated protein 1(Keap1)/nuclear factor erythroid 2-related factor 2(Nrf2)axis has emerged as a critical therapeutic target for mitigating post-MI cardiac injury.Methods:A murine MI model was established by permanent ligation of the left anterior descending coronary artery.Mice received oral Tongxinbi formula(TXB)at low,medium,or high doses(9/18/36 g/kg)once daily for 28 days.Cardiac function was assessed by echocardiography;myocardial fibrosis by Masson’s trichrome;and endothelial integrity by CD31 immunofluorescence.Plasma markers of endothelial function and inflammation were quantified.In vitro,oxidative stress was induced by H2O2 in vascular endothelial cells and cardiomyocytes,followed by treatment with TXB drug-containing serum.Western blot and RT-qPCR were used to measure components of the Keap1/Nrf2 pathway;ELISA quantified oxidative stress and inflammatory indices.Conditioned-medium experiments evaluated endothelial cell–mediated paracrine protection of cardiomyocytes.Results:TXB significantly improved cardiac function and reduced myocardial fibrosis after MI,in association with preservation of microvascular structure and systemic attenuation of oxidative stress and inflammation.In vitro,TXB activated the endothelial Keap1/Nrf2 pathway,enhanced cellular antioxidant defenses,increased VEGF secretion,and,via endothelial cell-mediated paracrine signaling,alleviated cardiomyocyte injury under oxidative stress.Conclusion:TXB exerts anti-fibrotic and cardioprotective effects by activating Nrf2 signaling and engaging endothelial-mediated paracrine mechanisms,collectively mitigating oxidative stress and inflammation in the post-MI setting.
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 grants from the Beijing Municipal Public Welfare Development and Reform Pilot Project for Medical Research Institutes(PWD&RPP-MRI,JYY2023-6)the R&D Program of Beijing Municipal Education Commission(KZ20231002543).
文摘Background:Dry eye disease(DED)predominantly results from elevated tear film os-molarity,which can not only cause ocular inconvenience but may lead to visual impair-ments,severely compromising patient well-being and exerting substantial economic burdens as well.Astaxanthin(AST),a member of the xanthophylls and recognized for its robust abilities to combat inflammation and oxidation,is a common dietary sup-plement.Nonetheless,the precise molecular pathways through which AST influences DED are still poorly understood.Methods:Therapeutic targets for AST were identified using data from the GeneCards,PharmMapper,and Swiss Target Prediction databases,and STITCH datasets.Similarly,targets for dry eye disease(DED)were delineated leveraging resources such as the Therapeutic Target Database(TTD),DisGeNET,GeneCards,and OMIM databases,and DrugBank datasets.Interactions among shared targets were charted and dis-played using CytoScape 3.9.0.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were conducted to elucidate the functions of pivotal tar-gets within the protein-protein interaction network.Molecular interactions between AST and key targets were confirmed through molecular docking using AutoDock and PyMOL.Molecular dynamics simulations were performed using GROMACS 2022.3.Viability of human corneal epithelial cells(hCEC)was assessed across varying concen-trations of AST.A mouse model of experimental DED was developed using 0.1%ben-zalkonium chloride(BAC),and the animals were administered 100 mg/kg/day of AST orally for 7 days.The efficacy of the treatments was assessed through a series of di-agnostic tests to evaluate the condition of the ocular surface after the interventions.The levels of inflammation and oxidative stress were quantitatively assessed using methods such as reverse transcription-polymerase chain reaction(RT-PCR),Western blot,and immunofluorescence staining.Results:Network pharmacology suggests that AST may alleviate DED by influenc-ing oxidation-reduction signaling pathways and reducing oxidative stress provoked by BAC.In vivo experiments demonstrated an improved overall condition in AST-administered mice in contrast to the control group.Immunofluorescence staining analyses indicated a decrease in Keap1 protein in the corneal tissues of AST-treated mice and a significant increase in Nrf2 and HO-1 protein.In vitro studies demon-strated that AST significantly enhanced cell viability and suppressed reactive oxy-gen species expression under hyperosmotic(HS)conditions,thereby protecting the human corneal epithelium.Conclusion:AST is capable of shielding mice from BAC-induced DED,decelerating the progression of DED,and mitigating oxidative stress damage under HS conditions in hCEC cells.The protective impact of AST on DED may operate through stimulating the Keap1-Nrf2/HO-1 signaling pathway.Our research findings indicate that AST may be a promising treatment for DED,offering new insights into DED treatment.
