Herpes simplex virus (HSV)-associated erythema multiforme (HAEM) is a recurrent disease characterized by the presence and expression of HSV DNA fragments in lesional skin. Our studies examined the mechanism of viral D...Herpes simplex virus (HSV)-associated erythema multiforme (HAEM) is a recurrent disease characterized by the presence and expression of HSV DNA fragments in lesional skin. Our studies examined the mechanism of viral DNA transport to the skin of HAEM patients. CD34+cells were isolated from the blood of normal subjects and HSV and HAEM patients during acute lesions and at quiescence. They were cultured with cytokines that favor their differentiation into Langerhans cells (LC) precursors (CD1a+/CD14-) and examined for HSV replication, HSV-induced cellular alterations, viral DNA fragmentation, and clearance. CD34+cells from all study groups were non-permissive for HSV replication but infection favored their differentiation into CD1a+/CD14-LC precursors and upregulated E-cadherin expression, thereby assisting LC targeting to the skin. Only HAEM patients had CD34+cells that retained viral DNA fragments, notably polymerase DNA, for at least 7 d of in vitro culture. The percentages of circulating CD34+(and CD34+/CLA+) cells were significantly higher in HAEM patients at the time of acute lesions. A similar increase was not seen for HSV patients. The data are the first report implicating CD34+cells in HAEM pathogenesis, likely by transporting HSV DNA fragments to lesional skin.展开更多
AIM:To investigate the protective role of ghrelin against diabetic retinopathy(DR),focusing on its anti-ferroptotic mechanism in high glucose-induced retinal endothelial injury.METHODS:First,small interfering RNA(siRN...AIM:To investigate the protective role of ghrelin against diabetic retinopathy(DR),focusing on its anti-ferroptotic mechanism in high glucose-induced retinal endothelial injury.METHODS:First,small interfering RNA(siRNA)-mediated interference was conducted to knockdown nuclear factor erythroid 2-related factor 2(Nrf2).Using reverse transcription-polymerase chain reaction(RT-PCR),the expression level of Nrf2 was determined from human retinal microvascular endothelial cells(HRMECs)transfected with either si-NC or si-Nrf2.After that,cells were treated with 10 nmol/L ghrelin and then cultured in a high glucose(30 mmol/L)environment.EdU assay was utilized to assess cell proliferation,while transmission electron microscopy was employed to observe mitochondrial morphology.Flow cytometry was used to measure the level of intracellular reactive oxygen species(ROS),and biochemical assays were conducted to detect malondialdehyde(MDA),glutathione(GSH),superoxide dismutase(SOD),and ferrous iron(Fe2+).Western blotting was used to identify the presence of ferroptosis-related proteins such as glutathione peroxidase 4(GPX4),solute carrier family 7 member 11(SLC7A11),Nrf2,and haem oxygenase-1(HO-1).RESULTS:Under a high glucose environment,ghrelin could significantly promote the proliferation of HRMECs and mitochondrial status,remarkably decrease the levels of intracellular ROS and MDA,and up-regulate the level of GSH and SOD.Besides,ghrelin greatly reduced Fe2+level in the cells while increased protein levels of GPX4 and SLC7A11.Subsequently,we found that high glucose induced inactivation of Nrf2/HO-1 axis and the protein expression profile were significantly promoted by ghrelin.Moreover,silencing of Nrf2 by siRNA delivery markedly diminished the changes induced by ghrelin in high glucose-induced HRMECs,shown as reduced cell proliferation and increased mitochondrial malformation,up-regulated ROS,MDA,Fe^(2+),GPX4 and SLC7A11,as well as down-regulated GSH,SOD,Nrf2 and HO-1.CONCLUSION:Ghrelin attenuates high glucose-induced injury of retinal endothelial cells via inhibiting ferroptosis,and activation of Nrf2/HO-1 pathway may be one of the mechanisms involved in this effect of ghrelin.展开更多
The carcinogenic potential of iron in colorectal cancer(CRC) is not fully understood.Iron is able to undergo reduction and oxidation,making it important in many physiological processes.This inherent redox property of ...The carcinogenic potential of iron in colorectal cancer(CRC) is not fully understood.Iron is able to undergo reduction and oxidation,making it important in many physiological processes.This inherent redox property of iron,however,also renders it toxic when it is present in excess.Iron-mediated generation of reactive oxygen species via the Fenton reaction,if uncontrolled,may lead to cell damage as a result of lipid peroxidation and oxidative DNA and protein damage.This may promote carcinogenesis through increased genomic instability,chromosomal rearrangements as well as mutations of proto-oncogenes and tumour suppressor genes. Carcinogenesis is also affected by inflammation which is exacerbated by iron.Population studies indicate an association between high dietary iron intake and CRC risk.In this editorial,we examine the link betweeniron-induced oxidative stress and inflammation on the pathogenesis of CRC.展开更多
Ischemia reperfusion injury is a major obstacle in liver resection and liver transplantation surgery.Understanding the mechanisms of liver ischemia reperfusion injury(IRI) and developing strategies to counteract this ...Ischemia reperfusion injury is a major obstacle in liver resection and liver transplantation surgery.Understanding the mechanisms of liver ischemia reperfusion injury(IRI) and developing strategies to counteract this injury will therefore reduce acute complications in hepatic resection and transplantation,as well as expanding the potential pool of usable donor grafts.The initial liver injury is initiated by reactive oxygen species which cause direct cellular injury and also activate a cascade of molecular mediators leading to microvascular changes,increased apoptosis and acute inflammatory changes with increased hepatocyte necrosis.Some adaptive pathways are activated during reperfusion that reduce the reperfusion injury.IRI involves a complex interplay between neutrophils,natural killer T-cells cells,CD4+ T cell subtypes,cytokines,nitric oxide synthases,haem oxygenase-1,survival kinases such as the signal transducer and activator of transcription,Phosphatidylinositol 3-kinases/Akt and nuclear factor κβ pathways.Transgenic animals,particularly genetic knockout models,have become a powerful tool at elucidating mechanisms of liver ischaemia reperfusion injury and are complementary to pharmacological studies.Targeted disruption of the protein at the genetic level is more specific and maintained than pharmacological inhibitors or stimulants of the same protein.This article reviews the evidence from knockout models of liver IRI about the cellular and molecular mechanisms underlying liver IRI.展开更多
文摘Herpes simplex virus (HSV)-associated erythema multiforme (HAEM) is a recurrent disease characterized by the presence and expression of HSV DNA fragments in lesional skin. Our studies examined the mechanism of viral DNA transport to the skin of HAEM patients. CD34+cells were isolated from the blood of normal subjects and HSV and HAEM patients during acute lesions and at quiescence. They were cultured with cytokines that favor their differentiation into Langerhans cells (LC) precursors (CD1a+/CD14-) and examined for HSV replication, HSV-induced cellular alterations, viral DNA fragmentation, and clearance. CD34+cells from all study groups were non-permissive for HSV replication but infection favored their differentiation into CD1a+/CD14-LC precursors and upregulated E-cadherin expression, thereby assisting LC targeting to the skin. Only HAEM patients had CD34+cells that retained viral DNA fragments, notably polymerase DNA, for at least 7 d of in vitro culture. The percentages of circulating CD34+(and CD34+/CLA+) cells were significantly higher in HAEM patients at the time of acute lesions. A similar increase was not seen for HSV patients. The data are the first report implicating CD34+cells in HAEM pathogenesis, likely by transporting HSV DNA fragments to lesional skin.
基金Supported by the Scientific Research Development Project of North Sichuan Medical College(No.CBY24-QDA01)Science and Technology Program of Shaanxi Province(No.2024SF-YBXM-324,No.2024SFYBXM-341).
文摘AIM:To investigate the protective role of ghrelin against diabetic retinopathy(DR),focusing on its anti-ferroptotic mechanism in high glucose-induced retinal endothelial injury.METHODS:First,small interfering RNA(siRNA)-mediated interference was conducted to knockdown nuclear factor erythroid 2-related factor 2(Nrf2).Using reverse transcription-polymerase chain reaction(RT-PCR),the expression level of Nrf2 was determined from human retinal microvascular endothelial cells(HRMECs)transfected with either si-NC or si-Nrf2.After that,cells were treated with 10 nmol/L ghrelin and then cultured in a high glucose(30 mmol/L)environment.EdU assay was utilized to assess cell proliferation,while transmission electron microscopy was employed to observe mitochondrial morphology.Flow cytometry was used to measure the level of intracellular reactive oxygen species(ROS),and biochemical assays were conducted to detect malondialdehyde(MDA),glutathione(GSH),superoxide dismutase(SOD),and ferrous iron(Fe2+).Western blotting was used to identify the presence of ferroptosis-related proteins such as glutathione peroxidase 4(GPX4),solute carrier family 7 member 11(SLC7A11),Nrf2,and haem oxygenase-1(HO-1).RESULTS:Under a high glucose environment,ghrelin could significantly promote the proliferation of HRMECs and mitochondrial status,remarkably decrease the levels of intracellular ROS and MDA,and up-regulate the level of GSH and SOD.Besides,ghrelin greatly reduced Fe2+level in the cells while increased protein levels of GPX4 and SLC7A11.Subsequently,we found that high glucose induced inactivation of Nrf2/HO-1 axis and the protein expression profile were significantly promoted by ghrelin.Moreover,silencing of Nrf2 by siRNA delivery markedly diminished the changes induced by ghrelin in high glucose-induced HRMECs,shown as reduced cell proliferation and increased mitochondrial malformation,up-regulated ROS,MDA,Fe^(2+),GPX4 and SLC7A11,as well as down-regulated GSH,SOD,Nrf2 and HO-1.CONCLUSION:Ghrelin attenuates high glucose-induced injury of retinal endothelial cells via inhibiting ferroptosis,and activation of Nrf2/HO-1 pathway may be one of the mechanisms involved in this effect of ghrelin.
基金Supported by Grants from the Cancer Council of Western Australia and Fremantle Hospital Medical Research Foundation
文摘The carcinogenic potential of iron in colorectal cancer(CRC) is not fully understood.Iron is able to undergo reduction and oxidation,making it important in many physiological processes.This inherent redox property of iron,however,also renders it toxic when it is present in excess.Iron-mediated generation of reactive oxygen species via the Fenton reaction,if uncontrolled,may lead to cell damage as a result of lipid peroxidation and oxidative DNA and protein damage.This may promote carcinogenesis through increased genomic instability,chromosomal rearrangements as well as mutations of proto-oncogenes and tumour suppressor genes. Carcinogenesis is also affected by inflammation which is exacerbated by iron.Population studies indicate an association between high dietary iron intake and CRC risk.In this editorial,we examine the link betweeniron-induced oxidative stress and inflammation on the pathogenesis of CRC.
文摘Ischemia reperfusion injury is a major obstacle in liver resection and liver transplantation surgery.Understanding the mechanisms of liver ischemia reperfusion injury(IRI) and developing strategies to counteract this injury will therefore reduce acute complications in hepatic resection and transplantation,as well as expanding the potential pool of usable donor grafts.The initial liver injury is initiated by reactive oxygen species which cause direct cellular injury and also activate a cascade of molecular mediators leading to microvascular changes,increased apoptosis and acute inflammatory changes with increased hepatocyte necrosis.Some adaptive pathways are activated during reperfusion that reduce the reperfusion injury.IRI involves a complex interplay between neutrophils,natural killer T-cells cells,CD4+ T cell subtypes,cytokines,nitric oxide synthases,haem oxygenase-1,survival kinases such as the signal transducer and activator of transcription,Phosphatidylinositol 3-kinases/Akt and nuclear factor κβ pathways.Transgenic animals,particularly genetic knockout models,have become a powerful tool at elucidating mechanisms of liver ischaemia reperfusion injury and are complementary to pharmacological studies.Targeted disruption of the protein at the genetic level is more specific and maintained than pharmacological inhibitors or stimulants of the same protein.This article reviews the evidence from knockout models of liver IRI about the cellular and molecular mechanisms underlying liver IRI.