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
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
Objectives The discovery of novel molecular targets to enhance the osteogenesis of human bone marrow-derived mesenchymal stem cells(H-BMSCs)represents a promising strategy for preventing and treating osteoporosis.Thus...Objectives The discovery of novel molecular targets to enhance the osteogenesis of human bone marrow-derived mesenchymal stem cells(H-BMSCs)represents a promising strategy for preventing and treating osteoporosis.Thus,the primary objective of this study is to elucidate the mechanisms by which long non-coding RNA FOXD2-AS1(lncRNA FOXD2-AS1)regulates early osteogenic differentiation in H-BMSCs,thereby identifying potential therapeutic targets.Methods Lentivirus-mediated vectors were constructed to either overexpress or silence FOXD2-AS1 in H-BMSCs.The effects of FOXD2-AS1 on osteogenesis were subsequently assessed by analyzing osteogenic marker expression and alkaline phosphatase(ALP)staining.To clarify the role of the Janus kinase 2/signal transducer and activator of transcription 3(JAK2/STAT3)pathway in this process,AG490 inhibitor(a JAK2/STAT3 pathway inhibitor)and knockdown of STAT3 were used to investigate the mechanisms of FOXD2-AS1.Results FOXD2-AS1 overexpression increased ALP activity and osteogenic marker expression,while its knockdown had the opposite effects.From a mechanistic perspective,FOXD2-AS1 overexpression promoted JAK2 and STAT3 phosphorylation,whereas its suppression attenuated their activation.Also,the osteogenic increase induced by FOXD2-AS1 overexpression was reversed by AG490 treatment or STAT3 silencing,indicating that the pathway plays a role in this process.Conclusion FOXD2-AS1 was identified as a novel genetic switch driving osteogenic commitment via JAK2/STAT3 activation,revealing a new regulatory mechanism and a potential therapeutic target for osteoporosis.展开更多
BACKGROUND IL-22 plays a pivotal role in the processes of inflammation and tissue healing.,but its role in cholangiocarcinoma(CCA)remains unclear.our study explored the IL-22/IL-22R1 pathway and its impact on CCA prog...BACKGROUND IL-22 plays a pivotal role in the processes of inflammation and tissue healing.,but its role in cholangiocarcinoma(CCA)remains unclear.our study explored the IL-22/IL-22R1 pathway and its impact on CCA progression through the ERK1/2 signaling cascade.AIM To determine the mechanism of the IL-22/IL-22R1 pathway in CCA and provide new directions for its clinical treatment.METHODS IL-22R1 expression was assessed in human and rat CCA tissues utilizing immunohistochemical techniques,Western blot analysis,and quantitative reverse transcription PCR.The impact of IL-22 on CCA cells was assessed in vitro via tests for proliferation,migration,invasion,and apoptosis assays.The rat models of thioacetamide-induced CCA and subcutaneous xenografts in nude mice were used to assess the in vivo effects.ERK1/2 inhibitors were applied to elucidate the mechanistic role of the pathway.RESULTS IL-22R1 was overexpressed in CCA cell lines and tissues.IL-22 treatment increased the phosphorylation of ERK1/2,promoting tumor cell proliferation,migration,invasion,and resistance to apoptosis.ERK1/2 inhibition considerably reversed these effects both in vitro and in vivo.CONCLUSION The IL-22/IL-22R1 axis promotes CCA progression by activating ERK1/2 signaling.Targeting this pathway with ERK1/2 inhibitors offers potential therapeutic strategies for CCA.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 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 the Natural Science Foundation of Hubei Province of China(Grant No.2023AFB671)the National Natural Science Foundation of China(Grant Nos.82360177 and 82560182)+1 种基金the Key Project of Jiangxi Provincial Natural Science Foundation(Grant No.20224ACB206011)“Xuncheng Talents”Project in Jiujiang City,Jiangxi Province(Grant No.JJXC2023071).
文摘Objectives The discovery of novel molecular targets to enhance the osteogenesis of human bone marrow-derived mesenchymal stem cells(H-BMSCs)represents a promising strategy for preventing and treating osteoporosis.Thus,the primary objective of this study is to elucidate the mechanisms by which long non-coding RNA FOXD2-AS1(lncRNA FOXD2-AS1)regulates early osteogenic differentiation in H-BMSCs,thereby identifying potential therapeutic targets.Methods Lentivirus-mediated vectors were constructed to either overexpress or silence FOXD2-AS1 in H-BMSCs.The effects of FOXD2-AS1 on osteogenesis were subsequently assessed by analyzing osteogenic marker expression and alkaline phosphatase(ALP)staining.To clarify the role of the Janus kinase 2/signal transducer and activator of transcription 3(JAK2/STAT3)pathway in this process,AG490 inhibitor(a JAK2/STAT3 pathway inhibitor)and knockdown of STAT3 were used to investigate the mechanisms of FOXD2-AS1.Results FOXD2-AS1 overexpression increased ALP activity and osteogenic marker expression,while its knockdown had the opposite effects.From a mechanistic perspective,FOXD2-AS1 overexpression promoted JAK2 and STAT3 phosphorylation,whereas its suppression attenuated their activation.Also,the osteogenic increase induced by FOXD2-AS1 overexpression was reversed by AG490 treatment or STAT3 silencing,indicating that the pathway plays a role in this process.Conclusion FOXD2-AS1 was identified as a novel genetic switch driving osteogenic commitment via JAK2/STAT3 activation,revealing a new regulatory mechanism and a potential therapeutic target for osteoporosis.
基金National Natural Science Foundation of China,No.82372194.
文摘BACKGROUND IL-22 plays a pivotal role in the processes of inflammation and tissue healing.,but its role in cholangiocarcinoma(CCA)remains unclear.our study explored the IL-22/IL-22R1 pathway and its impact on CCA progression through the ERK1/2 signaling cascade.AIM To determine the mechanism of the IL-22/IL-22R1 pathway in CCA and provide new directions for its clinical treatment.METHODS IL-22R1 expression was assessed in human and rat CCA tissues utilizing immunohistochemical techniques,Western blot analysis,and quantitative reverse transcription PCR.The impact of IL-22 on CCA cells was assessed in vitro via tests for proliferation,migration,invasion,and apoptosis assays.The rat models of thioacetamide-induced CCA and subcutaneous xenografts in nude mice were used to assess the in vivo effects.ERK1/2 inhibitors were applied to elucidate the mechanistic role of the pathway.RESULTS IL-22R1 was overexpressed in CCA cell lines and tissues.IL-22 treatment increased the phosphorylation of ERK1/2,promoting tumor cell proliferation,migration,invasion,and resistance to apoptosis.ERK1/2 inhibition considerably reversed these effects both in vitro and in vivo.CONCLUSION The IL-22/IL-22R1 axis promotes CCA progression by activating ERK1/2 signaling.Targeting this pathway with ERK1/2 inhibitors offers potential therapeutic strategies for CCA.
