Objectives To evaluate the effect of hydrogen sulfide(H2S) postconditioning on myocardial ischemia-reperfusion (I/R) by pressure-volume loop(P-V loop). Methods The I/R model of rat in vivo was established by ligating ...Objectives To evaluate the effect of hydrogen sulfide(H2S) postconditioning on myocardial ischemia-reperfusion (I/R) by pressure-volume loop(P-V loop). Methods The I/R model of rat in vivo was established by ligating the left anterior descending coronary artery for 30min and reperfusing for 120 min.Wistar rats(n=32) were ran- domly divided into 4 groups;Sham operation,ischemia-reperfusion (I/R),Ischemic postconditioning(IPO) and H2S postconditioning.In sham operation,there was no ligation.In IPO,at the start of reperfusion,three cycles of 30s reperfusion and 30s LAD reocclusion preceded the 3h of reperfusion. In H2S postconditioning,NaHS(15μmol/kg,Sodium hydrosulfide)was administrated before coronary artery reperfusion. The heart rate(HR),I/R arrhythmia,the left ventricular end-systolic pressure(LVESP),left ventricular enddiastolic pressure(LVEDP),the slope of the end- systolic P-V relation(ESPVR) and the slope of the end-diastolic P-V relation(EDPVR) were detected.Infarct size was determined by scanning the images of the rat heart ventricular sections stained with Evans blue and TTC.Results Compared with I/R group,the I/R arrhythmia and the infarct size were decreased significantly(PPP2S postconditioning group.Conclusions Myocardial I/R injury was decreased by H2S post-conditioning, and it was sensitive and accurate to evaluate the heart function by P-V loop.展开更多
DNA2,a multifunctional enzyme with structure-specific nuclease,5'-to-3'helicase,and DNA-dependent ATPase activities,plays a pivotal role in the cellular response to DNA damage.However,its involvement in cerebr...DNA2,a multifunctional enzyme with structure-specific nuclease,5'-to-3'helicase,and DNA-dependent ATPase activities,plays a pivotal role in the cellular response to DNA damage.However,its involvement in cerebral ischemia/reperfusion(I/R)injury remains to be elucidated.This study investigated the involvement of DNA2 in cerebral I/R injury using conditional knockout(cKO)mice(Nestin-Cre)subjected to middle cerebral artery occlusion(MCAO),an established model of cerebral I/R.Results demonstrated a gradual up-regulation of DNA2 expression,peaking at 72 h post-MCAO.Notably,DNA2 cKO mice exhibited more pronounced brain injury,neurological deficits,and neuronal apoptosis within the penumbra following MCAO.Additionally,DNA2 expression was elevated in an oxygen-glucose deprivation/reoxygenation(OGD/R)cell culture model,and DNA2 knockdown(KD)exacerbated neuronal apoptosis and oxidative stress.Transcriptome analysis of ischemic penumbra tissues via RNA sequencing revealed significant down-regulation of Homer1 in DNA2 cKO mice.Furthermore,in vitro experiments demonstrated that overexpression of Homer1a ameliorated DNA2 KD-induced neuronal apoptosis.Collectively,these findings demonstrate that DNA2 deficiency exacerbates cerebral I/R injury through the down-regulation of Homer1a,highlighting a novel regulatory axis in ischemic neuroprotection.展开更多
Background Liver ischemia/reperfusion(I/R)injury is usually caused by hepatic inflow occlusion during liver surgery,and is frequently observed during war wounds and trauma.Hepatocyte ferroptosis plays a critical role ...Background Liver ischemia/reperfusion(I/R)injury is usually caused by hepatic inflow occlusion during liver surgery,and is frequently observed during war wounds and trauma.Hepatocyte ferroptosis plays a critical role in liver I/R injury,however,it remains unclear whether this process is controlled or regulated by members of the DEAD/DExH-box helicase(DDX/DHX)family.Methods The expression of DDX/DHX family members during liver I/R injury was screened using transcriptome analysis.Hepatocyte-specific Dhx58 knockout mice were constructed,and a partial liver I/R operation was performed.Single-cell RNA sequencing(scRNA-seq)in the liver post I/R suggested enhanced ferroptosis by Dhx58hep−/−.The mRNAs and proteins associated with DExH-box helicase 58(DHX58)were screened using RNA immunoprecipitation-sequencing(RIP-seq)and IP-mass spectrometry(IP-MS).Results Excessive production of reactive oxygen species(ROS)decreased the expression of the IFN-stimulated gene Dhx58 in hepatocytes and promoted hepatic ferroptosis,while treatment using IFN-αincreased DHX58 expression and prevented ferroptosis during liver I/R injury.Mechanistically,DHX58 with RNA-binding activity constitutively associates with the mRNA of glutathione peroxidase 4(GPX4),a central ferroptosis suppressor,and recruits the m6A reader YT521-B homology domain containing 2(YTHDC2)to promote the translation of Gpx4 mRNA in an m6A-dependent manner,thus enhancing GPX4 protein levels and preventing hepatic ferroptosis.Conclusions This study provides mechanistic evidence that IFN-αstimulates DHX58 to promote the translation of m6A-modified Gpx4 mRNA,suggesting the potential clinical application of IFN-αin the prevention of hepatic ferroptosis during liver I/R injury.展开更多
文摘Objectives To evaluate the effect of hydrogen sulfide(H2S) postconditioning on myocardial ischemia-reperfusion (I/R) by pressure-volume loop(P-V loop). Methods The I/R model of rat in vivo was established by ligating the left anterior descending coronary artery for 30min and reperfusing for 120 min.Wistar rats(n=32) were ran- domly divided into 4 groups;Sham operation,ischemia-reperfusion (I/R),Ischemic postconditioning(IPO) and H2S postconditioning.In sham operation,there was no ligation.In IPO,at the start of reperfusion,three cycles of 30s reperfusion and 30s LAD reocclusion preceded the 3h of reperfusion. In H2S postconditioning,NaHS(15μmol/kg,Sodium hydrosulfide)was administrated before coronary artery reperfusion. The heart rate(HR),I/R arrhythmia,the left ventricular end-systolic pressure(LVESP),left ventricular enddiastolic pressure(LVEDP),the slope of the end- systolic P-V relation(ESPVR) and the slope of the end-diastolic P-V relation(EDPVR) were detected.Infarct size was determined by scanning the images of the rat heart ventricular sections stained with Evans blue and TTC.Results Compared with I/R group,the I/R arrhythmia and the infarct size were decreased significantly(PPP2S postconditioning group.Conclusions Myocardial I/R injury was decreased by H2S post-conditioning, and it was sensitive and accurate to evaluate the heart function by P-V loop.
基金supported by the National Natural Science Foundation of China (32070979)Shenzhen Science and Technology Program (JCYJ20220530161604009,JCYJ20240813150734043)+3 种基金Key Research and Development Program of Shaanxi (2024SF,YBXM,050)Fundamental Research Funds for the Central Universities (31020190QD004,3102019YX01001)Double First-Class Project of China Pharmaceutical University (CPUQNJC22_02)Global Pharmaceutical Development Alliance Plan of China Pharmaceutical University (1302090024-05)。
文摘DNA2,a multifunctional enzyme with structure-specific nuclease,5'-to-3'helicase,and DNA-dependent ATPase activities,plays a pivotal role in the cellular response to DNA damage.However,its involvement in cerebral ischemia/reperfusion(I/R)injury remains to be elucidated.This study investigated the involvement of DNA2 in cerebral I/R injury using conditional knockout(cKO)mice(Nestin-Cre)subjected to middle cerebral artery occlusion(MCAO),an established model of cerebral I/R.Results demonstrated a gradual up-regulation of DNA2 expression,peaking at 72 h post-MCAO.Notably,DNA2 cKO mice exhibited more pronounced brain injury,neurological deficits,and neuronal apoptosis within the penumbra following MCAO.Additionally,DNA2 expression was elevated in an oxygen-glucose deprivation/reoxygenation(OGD/R)cell culture model,and DNA2 knockdown(KD)exacerbated neuronal apoptosis and oxidative stress.Transcriptome analysis of ischemic penumbra tissues via RNA sequencing revealed significant down-regulation of Homer1 in DNA2 cKO mice.Furthermore,in vitro experiments demonstrated that overexpression of Homer1a ameliorated DNA2 KD-induced neuronal apoptosis.Collectively,these findings demonstrate that DNA2 deficiency exacerbates cerebral I/R injury through the down-regulation of Homer1a,highlighting a novel regulatory axis in ischemic neuroprotection.
基金National Key Research and Development Program of China(2023YFC2505900)National Natural Science Foundation of China(92269204,82171755,92369106,82171749,82171811,82073184)+1 种基金Military Outstanding Youth Program(2020QN06119,01-SWK JYCJJ07,23SWAQ53)Program of Leading Talents in Shanghai,and Shanghai Shuguang Program(20SG39)。
文摘Background Liver ischemia/reperfusion(I/R)injury is usually caused by hepatic inflow occlusion during liver surgery,and is frequently observed during war wounds and trauma.Hepatocyte ferroptosis plays a critical role in liver I/R injury,however,it remains unclear whether this process is controlled or regulated by members of the DEAD/DExH-box helicase(DDX/DHX)family.Methods The expression of DDX/DHX family members during liver I/R injury was screened using transcriptome analysis.Hepatocyte-specific Dhx58 knockout mice were constructed,and a partial liver I/R operation was performed.Single-cell RNA sequencing(scRNA-seq)in the liver post I/R suggested enhanced ferroptosis by Dhx58hep−/−.The mRNAs and proteins associated with DExH-box helicase 58(DHX58)were screened using RNA immunoprecipitation-sequencing(RIP-seq)and IP-mass spectrometry(IP-MS).Results Excessive production of reactive oxygen species(ROS)decreased the expression of the IFN-stimulated gene Dhx58 in hepatocytes and promoted hepatic ferroptosis,while treatment using IFN-αincreased DHX58 expression and prevented ferroptosis during liver I/R injury.Mechanistically,DHX58 with RNA-binding activity constitutively associates with the mRNA of glutathione peroxidase 4(GPX4),a central ferroptosis suppressor,and recruits the m6A reader YT521-B homology domain containing 2(YTHDC2)to promote the translation of Gpx4 mRNA in an m6A-dependent manner,thus enhancing GPX4 protein levels and preventing hepatic ferroptosis.Conclusions This study provides mechanistic evidence that IFN-αstimulates DHX58 to promote the translation of m6A-modified Gpx4 mRNA,suggesting the potential clinical application of IFN-αin the prevention of hepatic ferroptosis during liver I/R injury.
