目的观察重组人促红细胞生成素(recombinant human erythropoietin,rhEPO)对缺血/再灌注损伤大鼠心肌细胞Mitofusin2(Mfn2)蛋白表达的影响及其抗心肌细胞凋亡的作用。方法选取成年SD大鼠35只,随机分为正常组(Normal),假手术组(Sham),缺...目的观察重组人促红细胞生成素(recombinant human erythropoietin,rhEPO)对缺血/再灌注损伤大鼠心肌细胞Mitofusin2(Mfn2)蛋白表达的影响及其抗心肌细胞凋亡的作用。方法选取成年SD大鼠35只,随机分为正常组(Normal),假手术组(Sham),缺血再灌注组(I/R),缺血再灌注EPO治疗组(I/R+EPO)。各组分别于再灌注3h和24h后,剪取心脏缺血/再灌注损伤区域,用脱氧核苷酸末端转移酶介导的缺口末端标记法(TUNEL)检测心肌细胞凋亡,免疫组化法检测Mfn2蛋白的表达。结果再灌注3h和24h后,与正常组和假手术组相比,I/R组Mfn2蛋白的表达和心肌细胞凋亡均显著增加;与I/R组相比,I/R+EPO组Mfn2蛋白的表达和心肌细胞凋亡均显著降低。结论EPO可以下调缺血再灌注损伤后心肌细胞Mfn2蛋白的表达,抑制心肌细胞的凋亡。展开更多
This study aimed to elucidate the molecular mechanisms by which berberine protects against cerebral ischemia/reperfusion(I/R)injury.The oxygen-glucose deprivation/reperfusion(OGD/R)PC12 model was established.Cell coun...This study aimed to elucidate the molecular mechanisms by which berberine protects against cerebral ischemia/reperfusion(I/R)injury.The oxygen-glucose deprivation/reperfusion(OGD/R)PC12 model was established.Cell counting kit-8(CCK-8)was used to detect the toxicity of berberine and the viability of PC12 cells.Hoechst 33258 staining and flow cytometry were used to observe the nuclear morphology,and changes of apoptosis and reactive oxygen species(ROS),respectively.Western blotting and immunofluorescence assay were employed to detect autophagy-related proteins[microtubule-associated protein 1A/1B-light chain 3(LC3),P62/SQSTM-1,Beclin-1]and endoplasmic reticulum(ER)stress-related markers[glucose-regulated protein 78(GRP78),C/EBP homologous protein(CHOP),Bcl-2-associated X(Bax)and cleaved caspase-3].The GFP-RFP-LC3 adenovirus was used to assay the change of autophagic flux.Our results showed that berberine could increase the viability of PC12 cells,decrease the concentrations of ROS after OGD/R treatment,and suppress OGD/R-induced ER stress and autophagy.Moreover,the results revealed the involvement of the mammalian target of rapamycin(mTOR)pathway in the induction of autophagy,and berberine could activate the phosphorylation of mTOR and thus mitigate autophagy.In conclusion,our study suggested that berberine may protect against OGD/R-induced apoptosis by regulating ER stress and autophagy,and it holds promises in the treatment of cerebral I/R injury.展开更多
Background and Aims:Hepatic ischemia/reperfusion(I/R)injury has become an inevitable issue during liver transplantation,with no effective treatments available.However,peptide drugs provide promising regimens for the t...Background and Aims:Hepatic ischemia/reperfusion(I/R)injury has become an inevitable issue during liver transplantation,with no effective treatments available.However,peptide drugs provide promising regimens for the treatment of this injury and peptidomics has gradually attracted increasing attention.This study was designed to analyze the spectrum of peptides in injured livers and explore the potential beneficial peptides involved in I/R injury.Methods:C57BL/6 mice were used to establish a liver I/R injury animal model.Changes in peptide profiles in I/R-injured livers were analyzed by mass spectrometry,and the functions of the identified peptides were predicted by bioinformatics.AML12 cells were used to simulate hepatic I/R injury in vitro.After treatment with candidate liver-derived peptides(LDPs)1–10,the cells were collected at various reperfusion times for further study.Results:Our preliminary study demonstrated that 6 h of reperfusion caused the most liver I/R injury.Peptidomic results suggested that 10 down-regulated peptides were most likely to alleviate I/R injury by supporting mitochondrial function.Most importantly,a novel peptide,LDP2,was identified that alleviated I/R injury of AML12 cells.It increased cell viability and reduced the expression of inflammation-and apoptosis-related proteins.In addition,LDP2 inhibited the expression of proteins related to autophagy.Conclusions:Investigation of changes in the profiles of peptides in I/R-injured livers led to identification of a novel peptide,LDP2 with potential function in liver protection by inhibiting inflammation,apoptosis,and autophagy.展开更多
The effect of chronic ozone exposure to ischemia reperfusion (I/R) injury in isolated perfused rat hearts was previously demonstrated. The present study tested our hypothesis that chronic ozone exposure led to attenua...The effect of chronic ozone exposure to ischemia reperfusion (I/R) injury in isolated perfused rat hearts was previously demonstrated. The present study tested our hypothesis that chronic ozone exposure led to attenuation of polyamines in the heart, which may limit sensitivity to I/R. Sprague Dawley rats were continuously exposed for 8 hrs/day for 28 days to filtered air or 0.8 ppm ozone. Isolated hearts were previously subjected to 0.5 hour of global ischemia followed by 1 hour of reperfusion after which global polyamine content was examined between the two groups. Spermidine production was significantly increased in the experimental group compared to control group (of I/R hearts). These results suggest that ozone-induced sensitivity to chronic I/R injury activates myocardial polyamine stress response characterized by increased enzymatic activities and accumulation of spermidine. Collectively, these results suggest that I/R possibly disturbs polyamine metabolism, and increased oxidative stress and concomitant reduced myocardial cell viability.展开更多
It had been proved that administration of sevoflurane for the first two minutes of reperfusion effectively protects the heart against reperfusion injury in rats in vivo.Our aim was to investigate the duration of effec...It had been proved that administration of sevoflurane for the first two minutes of reperfusion effectively protects the heart against reperfusion injury in rats in vivo.Our aim was to investigate the duration of effective sevoflurane administration and its underlying mechanism in isolated rat hearts exposed to global ischemia/reperfusion(I/R) injury.Adult male Sprague-Dawley rats were randomly divided into six groups(n=12):a sham-operation group,an I/R group,and four sevoflurane postconditioning groups(S2,S5,S10,and S15).In the S2,S5,S10,and S15 groups,the duration times of sevoflurane administration were 2,5,10,and 15 min after the onset of reperfusion,respectively.The isolated rat hearts were mounted on the Langendorff system,and after a period of equilibrium were subjected to 40 min global ischemia and 120 min reperfusion.Left ventricular(LV) hemodynamic parameters were monitored throughout each experiment and the data at 30 min of equilibrium and 30,60,90,and 120 min of reperfusion were analyzed.Myocardial infarct size at the end of reperfusion(n=7 in each group) and the expression of myocardial phosphorylated Akt(p-Akt) after 15-min reperfusion were determined in a duplicate set of six groups of rat hearts(n=5 in each group).Compared with the I/R group,the S5,S10,and S15 groups had significantly improved left ventricular end-diastolic pressure(LVEDP),left ventricular developed pressure(LVDP),and the maximal rate of rise or fall of the LV pressure(±dP/dtmax),and decreased myocardial infarct size(P<0.05),but not the S2 group.After 15 min of reperfusion,the expression of p-Akt was markedly up-regulated in the S5,S10,and S15 groups compared with that in the I/R group(P<0.05),but not in the S2 group.Sevoflurane postconditioning for 5 min was sufficient to activate Akt and exert maximal cardioprotection against I/R injury in isolated rat hearts.展开更多
文摘目的观察重组人促红细胞生成素(recombinant human erythropoietin,rhEPO)对缺血/再灌注损伤大鼠心肌细胞Mitofusin2(Mfn2)蛋白表达的影响及其抗心肌细胞凋亡的作用。方法选取成年SD大鼠35只,随机分为正常组(Normal),假手术组(Sham),缺血再灌注组(I/R),缺血再灌注EPO治疗组(I/R+EPO)。各组分别于再灌注3h和24h后,剪取心脏缺血/再灌注损伤区域,用脱氧核苷酸末端转移酶介导的缺口末端标记法(TUNEL)检测心肌细胞凋亡,免疫组化法检测Mfn2蛋白的表达。结果再灌注3h和24h后,与正常组和假手术组相比,I/R组Mfn2蛋白的表达和心肌细胞凋亡均显著增加;与I/R组相比,I/R+EPO组Mfn2蛋白的表达和心肌细胞凋亡均显著降低。结论EPO可以下调缺血再灌注损伤后心肌细胞Mfn2蛋白的表达,抑制心肌细胞的凋亡。
基金This work was supported by grants from the National Natural Science Foundation of China(No.81360199)Science and Technology Department of Guizhou Province(Guizhou Specific Grant[2019]4008)+2 种基金Science and Technology Plan Project of Guizhou Province(Basic Science and Technology Cooperation[2020]1Z060)Science and Technology Fund Project of Guizhou Health and Health Commission(No.gzwjkj2019-1-039)Science and Technology Fund Project of Southwest Guizhou Autonomous Prefecture(2019-1-10).
文摘This study aimed to elucidate the molecular mechanisms by which berberine protects against cerebral ischemia/reperfusion(I/R)injury.The oxygen-glucose deprivation/reperfusion(OGD/R)PC12 model was established.Cell counting kit-8(CCK-8)was used to detect the toxicity of berberine and the viability of PC12 cells.Hoechst 33258 staining and flow cytometry were used to observe the nuclear morphology,and changes of apoptosis and reactive oxygen species(ROS),respectively.Western blotting and immunofluorescence assay were employed to detect autophagy-related proteins[microtubule-associated protein 1A/1B-light chain 3(LC3),P62/SQSTM-1,Beclin-1]and endoplasmic reticulum(ER)stress-related markers[glucose-regulated protein 78(GRP78),C/EBP homologous protein(CHOP),Bcl-2-associated X(Bax)and cleaved caspase-3].The GFP-RFP-LC3 adenovirus was used to assay the change of autophagic flux.Our results showed that berberine could increase the viability of PC12 cells,decrease the concentrations of ROS after OGD/R treatment,and suppress OGD/R-induced ER stress and autophagy.Moreover,the results revealed the involvement of the mammalian target of rapamycin(mTOR)pathway in the induction of autophagy,and berberine could activate the phosphorylation of mTOR and thus mitigate autophagy.In conclusion,our study suggested that berberine may protect against OGD/R-induced apoptosis by regulating ER stress and autophagy,and it holds promises in the treatment of cerebral I/R injury.
基金supported by National Natural Science Foundation of China (82070634,82002495)Shanghai Natural Science Foundation (20ZR1451700)+3 种基金SJTU CrossDisciplinary Research Fund in Medicine and Engineering (YG2022QN117)Shanghai Key Medical Specialty Fund (ZK2019A15)Research Fund of Key Laboratory for Translational Research and Innovative Therapeutics of Gastrointestinal Oncology (ZDSYS-2021-04)National Key Research and Development Program (2021YFC2701903).
文摘Background and Aims:Hepatic ischemia/reperfusion(I/R)injury has become an inevitable issue during liver transplantation,with no effective treatments available.However,peptide drugs provide promising regimens for the treatment of this injury and peptidomics has gradually attracted increasing attention.This study was designed to analyze the spectrum of peptides in injured livers and explore the potential beneficial peptides involved in I/R injury.Methods:C57BL/6 mice were used to establish a liver I/R injury animal model.Changes in peptide profiles in I/R-injured livers were analyzed by mass spectrometry,and the functions of the identified peptides were predicted by bioinformatics.AML12 cells were used to simulate hepatic I/R injury in vitro.After treatment with candidate liver-derived peptides(LDPs)1–10,the cells were collected at various reperfusion times for further study.Results:Our preliminary study demonstrated that 6 h of reperfusion caused the most liver I/R injury.Peptidomic results suggested that 10 down-regulated peptides were most likely to alleviate I/R injury by supporting mitochondrial function.Most importantly,a novel peptide,LDP2,was identified that alleviated I/R injury of AML12 cells.It increased cell viability and reduced the expression of inflammation-and apoptosis-related proteins.In addition,LDP2 inhibited the expression of proteins related to autophagy.Conclusions:Investigation of changes in the profiles of peptides in I/R-injured livers led to identification of a novel peptide,LDP2 with potential function in liver protection by inhibiting inflammation,apoptosis,and autophagy.
文摘The effect of chronic ozone exposure to ischemia reperfusion (I/R) injury in isolated perfused rat hearts was previously demonstrated. The present study tested our hypothesis that chronic ozone exposure led to attenuation of polyamines in the heart, which may limit sensitivity to I/R. Sprague Dawley rats were continuously exposed for 8 hrs/day for 28 days to filtered air or 0.8 ppm ozone. Isolated hearts were previously subjected to 0.5 hour of global ischemia followed by 1 hour of reperfusion after which global polyamine content was examined between the two groups. Spermidine production was significantly increased in the experimental group compared to control group (of I/R hearts). These results suggest that ozone-induced sensitivity to chronic I/R injury activates myocardial polyamine stress response characterized by increased enzymatic activities and accumulation of spermidine. Collectively, these results suggest that I/R possibly disturbs polyamine metabolism, and increased oxidative stress and concomitant reduced myocardial cell viability.
基金Project supported by the National Natural Science Foundation of China (Nos. 81170118 and 81201496)the Zhejiang Provincial Natural Science Foundation of China (No. R2090259)+1 种基金the Medicine Administration Bureau of Zhejiang Province (No. 2011ZZ009)the Department of Science and Technology of Zhejiang Province (Nos. 2009C13G2010218 and 2012C33088),China
文摘It had been proved that administration of sevoflurane for the first two minutes of reperfusion effectively protects the heart against reperfusion injury in rats in vivo.Our aim was to investigate the duration of effective sevoflurane administration and its underlying mechanism in isolated rat hearts exposed to global ischemia/reperfusion(I/R) injury.Adult male Sprague-Dawley rats were randomly divided into six groups(n=12):a sham-operation group,an I/R group,and four sevoflurane postconditioning groups(S2,S5,S10,and S15).In the S2,S5,S10,and S15 groups,the duration times of sevoflurane administration were 2,5,10,and 15 min after the onset of reperfusion,respectively.The isolated rat hearts were mounted on the Langendorff system,and after a period of equilibrium were subjected to 40 min global ischemia and 120 min reperfusion.Left ventricular(LV) hemodynamic parameters were monitored throughout each experiment and the data at 30 min of equilibrium and 30,60,90,and 120 min of reperfusion were analyzed.Myocardial infarct size at the end of reperfusion(n=7 in each group) and the expression of myocardial phosphorylated Akt(p-Akt) after 15-min reperfusion were determined in a duplicate set of six groups of rat hearts(n=5 in each group).Compared with the I/R group,the S5,S10,and S15 groups had significantly improved left ventricular end-diastolic pressure(LVEDP),left ventricular developed pressure(LVDP),and the maximal rate of rise or fall of the LV pressure(±dP/dtmax),and decreased myocardial infarct size(P<0.05),but not the S2 group.After 15 min of reperfusion,the expression of p-Akt was markedly up-regulated in the S5,S10,and S15 groups compared with that in the I/R group(P<0.05),but not in the S2 group.Sevoflurane postconditioning for 5 min was sufficient to activate Akt and exert maximal cardioprotection against I/R injury in isolated rat hearts.
