Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell damage.However,the underlying mechanism remains unknown.In thi...Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell damage.However,the underlying mechanism remains unknown.In this study,we elucidated the molecular mechanism for and D-A_(1) to alleviate ACR-stimulated IPEC-J2 cell damage.ACR slightly activated nuclear factor erythroid 2-related factor 2(Nrf2)signaling and its target genes,but this activation could not reduce intestine cell damage.A_(1) and D-A_(1) could alleviate ACR-induced cell damage,but the effect was abrogated in cells transiently transfected with Nrf2 small interfering RNA(siRNA).Further investigation confirmed that A_(1) and D-A_(1) interacted with Ketch-like ECH-associated protein 1(Keapl),which boosted the stabilization of Nrf2,subsequently promoted the translocation of Nrf2 into the nucleus,and further increased the expression of antioxidant proteins,thereby inhibiting glutathione(GSH)consumption,maintaining redox balance and eventually alleviating ACR-induced cell damage.Importantly,there was no difference between A_(1) and D-A_(1) treated groups,indicating that A_(1) can tolerate gastrointestinal digestion and may be a potential compound to limit the toxicity of ACR.展开更多
Soluble receptor for advanced glycation end products(sRAGE)acts as a decoy sequestering of RAGE ligands,thus preventing the activation of the ligand-RAGE axis linking human diseases.However,the molecular mechanisms un...Soluble receptor for advanced glycation end products(sRAGE)acts as a decoy sequestering of RAGE ligands,thus preventing the activation of the ligand-RAGE axis linking human diseases.However,the molecular mechanisms underlying sRAGE remain unclear.In this study,THP-1 monocytes were cultured in normal glucose(NG,5.5 mmol/L)and high glucose(HG,15 mmol/L)to investigate the effects of diabetesrelevant glucose concentrations on sRAGE and interleukin-1β(IL-1β)secretion.The modulatory effects of epigallocatechin gallate(EGCG)in response to HG challenge were also evaluated.HG enhanced intracellular reactive oxygen species(ROS)generation and RAGE expression.The secretion of sRAGE,including esRAGE and cRAGE,was reduced under HG conditions,together with the downregulation of a disintegrin and metallopeptidase 10(ADAM10)and nuclear factor erythroid 2-related factor 2(Nrf2)nuclear translocation.Mechanistically,the HG effects were counteracted by siRAGE and exacerbated by siNrf2.Chromatin immunoprecipitation results showed that Nrf2 binding to the ADAM10 promoter and HG interfered with this binding.Our data reinforce the notion that RAGE and Nrf2 might be sRAGE-regulating factors.Under HG conditions,the treatment of EGCG reduced ROS generation and RAGE activation.EGCG-stimulated cRAGE release was likely caused by the upregulation of the Nrf2-ADAM10 pathway.EGCG inhibited HG-mediated NLRP3 inflammasome activation at least partly by stimulating sRAGE,thereby reducing IL-1βrelease.展开更多
Lung oncogenesis relies on intracellular cysteine to overcome oxidative stress.Several tumor types,including non-small cell lung cancer(NSCLC),upregulate the system x-c cystine/glutamate antiporter(xCT)through overexp...Lung oncogenesis relies on intracellular cysteine to overcome oxidative stress.Several tumor types,including non-small cell lung cancer(NSCLC),upregulate the system x-c cystine/glutamate antiporter(xCT)through overexpression of the cystine transporter SLC7A11,thus sustaining intracellular cysteine levels to support glutathione synthesis.Nuclear factor erythroid 2-related factor 2(NRF2)serves as a master regulator of oxidative stress resistance by regulating SLC7A11,whereas Kelch-like ECH-associated protein(KEAP1)acts as a cytoplasmic repressor of the oxidative responsive transcription factor NRF2.Mutations in KEAP1/NRF2 and p53 induce SLC7A11 activation in NSCLC.Extracellular cystine is crucial in supplying the intracellular cysteine levels necessary to combat oxidative stress.Disruptions in cystine availability lead to iron-dependent lipid peroxidation,thus resulting in a type of cell death called ferroptosis.Pharmacologic inhibitors of xCT(either SLC7A11 or GPX4)induce ferroptosis of NSCLC cells and other tumor types.When cystine uptake is impaired,the intracellular cysteine pool can be sustained by the transsulfuration pathway,which is catalyzed by cystathionine-B-synthase(CBS)and cystathionine g-lyase(CSE).The involvement of exogenous cysteine/cystine and the transsulfuration pathway in the cysteine pool and downstream metabolites results in compromised CD8^(+)T cell function and evasion of immunotherapy,diminishing immune response and potentially reducing the effectiveness of immunotherapeutic interventions.Pyroptosis is a previously unrecognized form of regulated cell death.In NSCLCs driven by EGFR,ALK,or KRAS,selective inhibitors induce pyroptotic cell death as well as apoptosis.After targeted therapy,the mitochondrial intrinsic apoptotic pathway is activated,thus leading to the cleavage and activation of caspase-3.Consequently,gasdermin E is activated,thus leading to permeabilization of the cytoplasmic membrane and cell-lytic pyroptosis(indicated by characteristic cell membrane ballooning).Breakthroughs in KRAS G12C allele-specific inhibitors and potential mechanisms of resistance are also discussed herein.展开更多
基金supported by the project from National Natural Science Foundation of China (31671962)Fundamental Research Funds for the Central Universities (2662019PY034)。
文摘Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell damage.However,the underlying mechanism remains unknown.In this study,we elucidated the molecular mechanism for and D-A_(1) to alleviate ACR-stimulated IPEC-J2 cell damage.ACR slightly activated nuclear factor erythroid 2-related factor 2(Nrf2)signaling and its target genes,but this activation could not reduce intestine cell damage.A_(1) and D-A_(1) could alleviate ACR-induced cell damage,but the effect was abrogated in cells transiently transfected with Nrf2 small interfering RNA(siRNA).Further investigation confirmed that A_(1) and D-A_(1) interacted with Ketch-like ECH-associated protein 1(Keapl),which boosted the stabilization of Nrf2,subsequently promoted the translocation of Nrf2 into the nucleus,and further increased the expression of antioxidant proteins,thereby inhibiting glutathione(GSH)consumption,maintaining redox balance and eventually alleviating ACR-induced cell damage.Importantly,there was no difference between A_(1) and D-A_(1) treated groups,indicating that A_(1) can tolerate gastrointestinal digestion and may be a potential compound to limit the toxicity of ACR.
文摘Soluble receptor for advanced glycation end products(sRAGE)acts as a decoy sequestering of RAGE ligands,thus preventing the activation of the ligand-RAGE axis linking human diseases.However,the molecular mechanisms underlying sRAGE remain unclear.In this study,THP-1 monocytes were cultured in normal glucose(NG,5.5 mmol/L)and high glucose(HG,15 mmol/L)to investigate the effects of diabetesrelevant glucose concentrations on sRAGE and interleukin-1β(IL-1β)secretion.The modulatory effects of epigallocatechin gallate(EGCG)in response to HG challenge were also evaluated.HG enhanced intracellular reactive oxygen species(ROS)generation and RAGE expression.The secretion of sRAGE,including esRAGE and cRAGE,was reduced under HG conditions,together with the downregulation of a disintegrin and metallopeptidase 10(ADAM10)and nuclear factor erythroid 2-related factor 2(Nrf2)nuclear translocation.Mechanistically,the HG effects were counteracted by siRAGE and exacerbated by siNrf2.Chromatin immunoprecipitation results showed that Nrf2 binding to the ADAM10 promoter and HG interfered with this binding.Our data reinforce the notion that RAGE and Nrf2 might be sRAGE-regulating factors.Under HG conditions,the treatment of EGCG reduced ROS generation and RAGE activation.EGCG-stimulated cRAGE release was likely caused by the upregulation of the Nrf2-ADAM10 pathway.EGCG inhibited HG-mediated NLRP3 inflammasome activation at least partly by stimulating sRAGE,thereby reducing IL-1βrelease.
基金supported by a Spanish Association Against Cancer(AECC)grant,(grant No.PROYE18012ROSE)support from Julián Santamaría Vali?o to the IOR Foundation。
文摘Lung oncogenesis relies on intracellular cysteine to overcome oxidative stress.Several tumor types,including non-small cell lung cancer(NSCLC),upregulate the system x-c cystine/glutamate antiporter(xCT)through overexpression of the cystine transporter SLC7A11,thus sustaining intracellular cysteine levels to support glutathione synthesis.Nuclear factor erythroid 2-related factor 2(NRF2)serves as a master regulator of oxidative stress resistance by regulating SLC7A11,whereas Kelch-like ECH-associated protein(KEAP1)acts as a cytoplasmic repressor of the oxidative responsive transcription factor NRF2.Mutations in KEAP1/NRF2 and p53 induce SLC7A11 activation in NSCLC.Extracellular cystine is crucial in supplying the intracellular cysteine levels necessary to combat oxidative stress.Disruptions in cystine availability lead to iron-dependent lipid peroxidation,thus resulting in a type of cell death called ferroptosis.Pharmacologic inhibitors of xCT(either SLC7A11 or GPX4)induce ferroptosis of NSCLC cells and other tumor types.When cystine uptake is impaired,the intracellular cysteine pool can be sustained by the transsulfuration pathway,which is catalyzed by cystathionine-B-synthase(CBS)and cystathionine g-lyase(CSE).The involvement of exogenous cysteine/cystine and the transsulfuration pathway in the cysteine pool and downstream metabolites results in compromised CD8^(+)T cell function and evasion of immunotherapy,diminishing immune response and potentially reducing the effectiveness of immunotherapeutic interventions.Pyroptosis is a previously unrecognized form of regulated cell death.In NSCLCs driven by EGFR,ALK,or KRAS,selective inhibitors induce pyroptotic cell death as well as apoptosis.After targeted therapy,the mitochondrial intrinsic apoptotic pathway is activated,thus leading to the cleavage and activation of caspase-3.Consequently,gasdermin E is activated,thus leading to permeabilization of the cytoplasmic membrane and cell-lytic pyroptosis(indicated by characteristic cell membrane ballooning).Breakthroughs in KRAS G12C allele-specific inhibitors and potential mechanisms of resistance are also discussed herein.
