Objective:To investigate the regulatory effect of Qiliqiangxin Capsule on mitochondrial Ca^(2+)related genes in rats with myocardial infarction(MI).Methods:The rat model of MI was established by ligation of the left a...Objective:To investigate the regulatory effect of Qiliqiangxin Capsule on mitochondrial Ca^(2+)related genes in rats with myocardial infarction(MI).Methods:The rat model of MI was established by ligation of the left anterior descending coronary artery.After operation,the rats were randomly assigned to the model group,the Qiliqiangxin group and the captopril group;a sham-operated group was also available as a control.After four weeks of treatment,the extent of infarction in rats was observed by gross cardiac structure and the morphological changes of myocardial histopathology were observed by HE staining.Detection of mitochondrial Ca^(2+)transport-related genes such as inositol-1,4,5-trisphosphate receptor 2(IP3R2),glucose regulated protein 75(GRP75),voltage-dependent anion channel 1(VDAC1),and mitofusion 2(Mfn2)and mitochondrial apoptosis-related genes such as B-cell lymphoma-2(Bcl-2)and Bcl-2 related X protein(Bax)mRNA expression changes was measured by RT-PCR in the infarct margins of the heart;Western blot was used to detect changes in Bcl-2,Bax protein expression in myocardial tissue.The rate of apoptosis in cardiac myocardial tissue was detected by TUNEL staining.Results:Compared with the sham group,the anterior left ventricular wall of the model group showed a large area of infarction,and the structure of myocardial tissue was disordered.The mRNA expression level of mitochondrial Ca^(2+)transport-related genes such as IP3R2,GRP75,VDAC1,and Mfn2 were significantly increased(P<0.05,P<0.01);The mRNA and protein expression of Bcl-2,a molecule related to mitochondrial apoptosis,were significantly decreased(P<0.01),while the mRNA and protein expression of Bax were significantly increased(P<0.01);and apoptosis rate was significantly increased(P<0.01).Compared with the model group,the infarct size of cardiac gross specimens in the Qiliqiangxin group and the captopril group was reduced and myocardial fibers were relatively well ordered;The mRNA expression of mitochondrial Ca^(2+)transport-related genes such as IP3R2,GRP75,VDAC1,and Mfn2 were significantly reduced(P<0.01);the mRNA and protein expression of Bcl-2,a molecule related to mitochondrial apoptosis,were increased(P<0.05,P<0.01),and the mRNA and protein expression of Bax were significantly decreased(P<0.05,P<0.01).and apoptosis rate was significantly decreased(P<0.01).Conclusion:Qiliqiangxin Capsule can improve the morphological structure of the heart of rats with MI,and its mechanism is related to regulation of the gene expression of mitochondrial Ca^(2+)transport complex IP3R2/GRP75/VDAC1,thereby inhibiting apoptosis.展开更多
Acetaminophen(APAP)overdose is a major cause of liver injury.Neural precursor cell expressed developmentally downregulated 4—1(NEDD4-1)is an E3 ubiquitin ligase that has been implicated in the pathogenesis of numerou...Acetaminophen(APAP)overdose is a major cause of liver injury.Neural precursor cell expressed developmentally downregulated 4—1(NEDD4-1)is an E3 ubiquitin ligase that has been implicated in the pathogenesis of numerous liver diseases;however,its role in APAP-induced liver injury(AILI)is unclear.Thus,this study aimed to investigate the role of NEDD4-1 in the pathogenesis of AILI.We found that NEDD4-1 was dramatically downregulated in response to APAP treatment in mouse livers and isolated mouse hepatocytes.Hepatocyte-specific NEDD4-1 knockout exacerbated APAP-induced mitochondrial damage and the resultant hepatocyte necrosis and liver injury,while hepatocyte-specific NEDD4-1 overexpression mitigated these pathological events both in vivo and in vitro.Additionally,hepatocyte NEDD4-1 deficiency led to marked accumulation of voltage-dependent anion channel 1(VDAC1)and increased VDAC1 oligomerization.Furthermore,VDAC1 knockdown alleviated AILI and weakened the exacerbation of AILI caused by hepatocyte NEDD4-1 deficiency.Mechanistically,NEDD4-1 was found to interact with the PPTY motif of VDAC1 through its WW domain and regulate K48-linked ubiquitination and degradation of VDAC1.Our present study indicates that NEDD4-1 is a suppressor of AILI and functions by regulating the degradation of VDAC1.展开更多
Background Alzheimer’s disease(AD)exhibits mitochondrial dysfunctions associated with dysregulated metabolism,brain inflammation,synaptic loss,and neuronal cell death.As a key protein serving as the mitochondrial gat...Background Alzheimer’s disease(AD)exhibits mitochondrial dysfunctions associated with dysregulated metabolism,brain inflammation,synaptic loss,and neuronal cell death.As a key protein serving as the mitochondrial gatekeeper,the voltage-dependent anion channel-1(VDAC1)that controls metabolism and Ca2+homeostasis is positioned at a convergence point for various cell survival and death signals.Here,we targeted VDAC1 with VBIT-4,a newly developed inhibitor of VDAC1 that prevents its pro-apoptotic activity,and mitochondria dysfunction.Methods To address the multiple pathways involved in AD,neuronal cultures and a 5×FAD mouse model of AD were treated with VBIT-4.We addressed multiple topics related to the disease and its molecular mechanisms using immunoblotting,immunofluorescence,q-RT-PCR,3-D structural analysis and several behavioral tests.Results In neuronal cultures,amyloid-beta(Aβ)-induced VDAC1 and p53 overexpression and apoptotic cell death were prevented by VBIT-4.Using an AD-like 5×FAD mouse model,we showed that VDAC1 was overexpressed in neurons surrounding Aβplaques,but not in astrocytes and microglia,and this was associated with neuronal cell death.VBIT-4 prevented the associated pathophysiological changes including neuronal cell death,neuroinflammation,and neuro-metabolic dysfunctions.VBIT-4 also switched astrocytes and microglia from being pro-inflammatory/neurotoxic to neuroprotective phenotype.Moreover,VBIT-4 prevented cognitive decline in the 5×FAD mice as evaluated using several behavioral assessments of cognitive function.Interestingly,VBIT-4 protected against AD pathology,with no significant change in phosphorylated Tau and only a slight decrease in Aβ-plaque load.Conclusions The study suggests that mitochondrial dysfunction with its gatekeeper VDAC1 is a promising target for AD therapeutic intervention,and VBIT-4 is a promising drug candidate for AD treatment.展开更多
基金This study was supported by Beijing University of Traditional Chinese Medicine Dongzhimen Hospital 2022 Science and Technology Innovation Special Project(DZMKJCX-2022-008)。
文摘Objective:To investigate the regulatory effect of Qiliqiangxin Capsule on mitochondrial Ca^(2+)related genes in rats with myocardial infarction(MI).Methods:The rat model of MI was established by ligation of the left anterior descending coronary artery.After operation,the rats were randomly assigned to the model group,the Qiliqiangxin group and the captopril group;a sham-operated group was also available as a control.After four weeks of treatment,the extent of infarction in rats was observed by gross cardiac structure and the morphological changes of myocardial histopathology were observed by HE staining.Detection of mitochondrial Ca^(2+)transport-related genes such as inositol-1,4,5-trisphosphate receptor 2(IP3R2),glucose regulated protein 75(GRP75),voltage-dependent anion channel 1(VDAC1),and mitofusion 2(Mfn2)and mitochondrial apoptosis-related genes such as B-cell lymphoma-2(Bcl-2)and Bcl-2 related X protein(Bax)mRNA expression changes was measured by RT-PCR in the infarct margins of the heart;Western blot was used to detect changes in Bcl-2,Bax protein expression in myocardial tissue.The rate of apoptosis in cardiac myocardial tissue was detected by TUNEL staining.Results:Compared with the sham group,the anterior left ventricular wall of the model group showed a large area of infarction,and the structure of myocardial tissue was disordered.The mRNA expression level of mitochondrial Ca^(2+)transport-related genes such as IP3R2,GRP75,VDAC1,and Mfn2 were significantly increased(P<0.05,P<0.01);The mRNA and protein expression of Bcl-2,a molecule related to mitochondrial apoptosis,were significantly decreased(P<0.01),while the mRNA and protein expression of Bax were significantly increased(P<0.01);and apoptosis rate was significantly increased(P<0.01).Compared with the model group,the infarct size of cardiac gross specimens in the Qiliqiangxin group and the captopril group was reduced and myocardial fibers were relatively well ordered;The mRNA expression of mitochondrial Ca^(2+)transport-related genes such as IP3R2,GRP75,VDAC1,and Mfn2 were significantly reduced(P<0.01);the mRNA and protein expression of Bcl-2,a molecule related to mitochondrial apoptosis,were increased(P<0.05,P<0.01),and the mRNA and protein expression of Bax were significantly decreased(P<0.05,P<0.01).and apoptosis rate was significantly decreased(P<0.01).Conclusion:Qiliqiangxin Capsule can improve the morphological structure of the heart of rats with MI,and its mechanism is related to regulation of the gene expression of mitochondrial Ca^(2+)transport complex IP3R2/GRP75/VDAC1,thereby inhibiting apoptosis.
基金supported by the National Natural Science Foundation of China(Beijing,ChinaGrant Nos.32022084 and 32172927)。
文摘Acetaminophen(APAP)overdose is a major cause of liver injury.Neural precursor cell expressed developmentally downregulated 4—1(NEDD4-1)is an E3 ubiquitin ligase that has been implicated in the pathogenesis of numerous liver diseases;however,its role in APAP-induced liver injury(AILI)is unclear.Thus,this study aimed to investigate the role of NEDD4-1 in the pathogenesis of AILI.We found that NEDD4-1 was dramatically downregulated in response to APAP treatment in mouse livers and isolated mouse hepatocytes.Hepatocyte-specific NEDD4-1 knockout exacerbated APAP-induced mitochondrial damage and the resultant hepatocyte necrosis and liver injury,while hepatocyte-specific NEDD4-1 overexpression mitigated these pathological events both in vivo and in vitro.Additionally,hepatocyte NEDD4-1 deficiency led to marked accumulation of voltage-dependent anion channel 1(VDAC1)and increased VDAC1 oligomerization.Furthermore,VDAC1 knockdown alleviated AILI and weakened the exacerbation of AILI caused by hepatocyte NEDD4-1 deficiency.Mechanistically,NEDD4-1 was found to interact with the PPTY motif of VDAC1 through its WW domain and regulate K48-linked ubiquitination and degradation of VDAC1.Our present study indicates that NEDD4-1 is a suppressor of AILI and functions by regulating the degradation of VDAC1.
基金The Israel Science Foundation,Grant No.974/19,and by a grant from the National Institute for Biotechnology in the Negev(NIBN)to VSB.
文摘Background Alzheimer’s disease(AD)exhibits mitochondrial dysfunctions associated with dysregulated metabolism,brain inflammation,synaptic loss,and neuronal cell death.As a key protein serving as the mitochondrial gatekeeper,the voltage-dependent anion channel-1(VDAC1)that controls metabolism and Ca2+homeostasis is positioned at a convergence point for various cell survival and death signals.Here,we targeted VDAC1 with VBIT-4,a newly developed inhibitor of VDAC1 that prevents its pro-apoptotic activity,and mitochondria dysfunction.Methods To address the multiple pathways involved in AD,neuronal cultures and a 5×FAD mouse model of AD were treated with VBIT-4.We addressed multiple topics related to the disease and its molecular mechanisms using immunoblotting,immunofluorescence,q-RT-PCR,3-D structural analysis and several behavioral tests.Results In neuronal cultures,amyloid-beta(Aβ)-induced VDAC1 and p53 overexpression and apoptotic cell death were prevented by VBIT-4.Using an AD-like 5×FAD mouse model,we showed that VDAC1 was overexpressed in neurons surrounding Aβplaques,but not in astrocytes and microglia,and this was associated with neuronal cell death.VBIT-4 prevented the associated pathophysiological changes including neuronal cell death,neuroinflammation,and neuro-metabolic dysfunctions.VBIT-4 also switched astrocytes and microglia from being pro-inflammatory/neurotoxic to neuroprotective phenotype.Moreover,VBIT-4 prevented cognitive decline in the 5×FAD mice as evaluated using several behavioral assessments of cognitive function.Interestingly,VBIT-4 protected against AD pathology,with no significant change in phosphorylated Tau and only a slight decrease in Aβ-plaque load.Conclusions The study suggests that mitochondrial dysfunction with its gatekeeper VDAC1 is a promising target for AD therapeutic intervention,and VBIT-4 is a promising drug candidate for AD treatment.
