The mitochondrial permeability transition pore is a nonspecific transmembrane channel.Inhibition of mitochondrial permeability transition pore opening has been shown to alleviate mitochondrial swelling,calcium overloa...The mitochondrial permeability transition pore is a nonspecific transmembrane channel.Inhibition of mitochondrial permeability transition pore opening has been shown to alleviate mitochondrial swelling,calcium overload,and axonal degeneration.Cyclophilin D is an important component of the mitochondrial permeability transition pore.Whether cyclophilin D participates in mitochondrial impairment and axonal injury after intracerebral hemorrhage is not clear.In this study,we established mouse models of intracerebral hemorrhage in vivo by injection of autologous blood and oxyhemoglobin into the striatum in Thy1-YFP mice,in which pyramidal neurons and axons express yellow fluorescent protein.We also simulated intracerebral hemorrhage in vitro in PC12 cells using oxyhemoglobin.We found that axonal degeneration in the early stage of intracerebral hemorrhage depended on mitochondrial swelling induced by cyclophilin D activation and mitochondrial permeability transition pore opening.We further investigated the mechanism underlying the role of cyclophilin D in mouse models and PC12 cell models of intracerebral hemorrhage.We found that both cyclosporin A inhibition and short hairpin RNA interference of cyclophilin D reduced mitochondrial permeability transition pore opening and mitochondrial injury.In addition,inhibition of cyclophilin D and mitochondrial permeability transition pore opening protected corticospinal tract integrity and alleviated motor dysfunction caused by intracerebral hemorrhage.Our findings suggest that cyclophilin D is used as a key mediator of axonal degeneration after intracerebral hemorrhage;inhibition of cyclophilin D expression can protect mitochondrial structure and function and further alleviate corticospinal tract injury and motor dysfunction after intracerebral hemorrhage.Our findings provide a therapeutic target for preventing axonal degeneration of white matter injury and subsequent functional impairment in central nervous diseases.展开更多
Cyclophilin D （referred to as HsCypD） was obtained from the freshwater pearl mussel （Hyriopsis schlegelil）. The full-length cDNA was 2 671 bp, encoding a protein consisting of 367 amino acids. HsCypD was determine...Cyclophilin D （referred to as HsCypD） was obtained from the freshwater pearl mussel （Hyriopsis schlegelil）. The full-length cDNA was 2 671 bp, encoding a protein consisting of 367 amino acids. HsCypD was determined to be a hydrophilic intracellular protein with 10 phosphorylation sites and four tetratricopeptide repeat （TPR） domains, but no signal peptide. The core sequence region YKGCIFHRIIKDFMVQGG is highly conserved in vertebrates and invertebrates. Phylogenetic tree analysis indicated that CypD from all species had a common origin, and HsCypD had the closest phylogenetic relationship with CypD from Lottia gigantea. The constitutive mRNA expression levels of HsCypD exhibited tissue-specific patterns, with the highest level detected in the intestines, followed by the gonads, and the lowest expression found in the hemocytes.展开更多
Background:Liver ischemia/reperfusion(I/R)injury is a complex and multifactorial pathophysiological process.It is well recognized that the membrane permeability transition pore(mPTP)opening of mitochondria plays a cru...Background:Liver ischemia/reperfusion(I/R)injury is a complex and multifactorial pathophysiological process.It is well recognized that the membrane permeability transition pore(mPTP)opening of mitochondria plays a crucial role in cell death after I/R injury.Cyclophilin D(CypD)is a critical positive regulator of mPTP.However,the effect of CypD on the pathogenesis of liver I/R injury and whether CypD is a potential therapeutic target are still unclear.Methods:We constructed liver-specific CypD knockout and AAV8-peptidyl prolyl isomerase F(PPIF)overexpression mice.Then,a 70%liver I/R injury model was established in mice,with 90 min of ischemia and 6 h of reperfusion.The liver function was detected by the level of serum glutamic pyruvic transaminase(alanine transaminase)and glutamic oxaloacetic transaminase(aspartate aminotransferase),the liver damage score and degree of necrosis were measured by hematoxylin and eosin(H&E)staining of liver tissues.Reactive oxygen species(ROS)staining,apoptosis,and autophagy-related molecules were used to detect apoptosis and autophagy during liver I/R.Results:The liver-specific knockout of CypD alleviated necrosis and dysfunction in liver I/R injury,by reducing the excessive production of ROS,and inhibiting cell apoptosis and autophagy.On the contrary,overexpression of CypD exacerbated I/R-induced liver damage.Conclusion:We found that the downregulation of CypD expression alleviated liver I/R injury by reducing apoptosis and autophagy through caspase-3/Beclin1 crosstalk;in contrast,the upregulation of CypD expression aggravated liver I/R injury.Therefore,interfering with the expression of CypD seems to be a promising treatment for liver I/R injury.展开更多
p53＇s apoptotic program consists of transcription-dependent and transcription-independent pathways. In the latter, physical interactions between mitochondrial p53 and anti- and pro-apoptotic members of the Bcl2 famil...p53＇s apoptotic program consists of transcription-dependent and transcription-independent pathways. In the latter, physical interactions between mitochondrial p53 and anti- and pro-apoptotic members of the Bcl2 family of mitochondrial permeability regulators are central. Using isogenic cell systems with defined deficiencies, we characterize in detail how mitochondrial p53 contributes to mitochondrial permeabilization, to what extent its action depends on other key Bcl2 family members and define its release activity. We show that mitochondrial p53 is highly efficient in inducing the release of soluble and insoluble apoptogenic factors by severely disrupting outer and inner mitochondrial membrane integrity. This action is associated with wild-type p53-induced oligomerization of Bax, Bak and VDAC and the formation of a stress-induced endogenous complex between p53 and cyclophilin D, normally located at the inner membrane. Tumor-derived p53 mutants are deficient in activating the Bax/Bak lipid pore. These actions are independent of Puma and Bax. Importantly, the latter distinguishes the mitochondrial from the cytosolic p53 death pathway.展开更多
The mitochondrion serves many functions in the central nervous system （CNS） and other organs beyond the well-recognized role of adenosine triphosphate （ATP） production. This includes calcium-dependent cell signali...The mitochondrion serves many functions in the central nervous system （CNS） and other organs beyond the well-recognized role of adenosine triphosphate （ATP） production. This includes calcium-dependent cell signaling, regulation of gene expression, synthesis and release of cytotoxic reactive oxygen species, and the release of cytochrome c and other apoptotic cell death factors. Traumatic injury to the CNS results in a rapid and, in some cases, sustained loss of mitochondrial function. One consequence of compromised mitochondrial function is induction of the mitochondrial permeability transition （mPT） state due to formation of the cyclosporine A sensitive permeability transition pore （mPTP）. In this mini-review, we summarize evidence supporting the involvement of the mPTP as a mediator of mitochondrial and cellular demise following CNS traumatic injury and discuss the beneficial effects and limitations of the current ex- perimental strategies targeting the mPTP.展开更多
The β-amyloid protein (Aβ) has long been considered to associate with Alzheimer’s disease (AD). In addition, groups of evidence show that the soluble intracellular Aβ plays an important role in the disease develop...The β-amyloid protein (Aβ) has long been considered to associate with Alzheimer’s disease (AD). In addition, groups of evidence show that the soluble intracellular Aβ plays an important role in the disease development. The mitochondrial dysfunction induced by Aβ accumulation is a main pathologic process in early stage of AD. Matured Aβ is imported into the mitochondria through an unclear route. Once inside the mitochondria, Aβ is able to interact with a number of targets, including amyloid-binding alcohol dehydrogenase (ABAD) and cyclophilin D (CypD), which is a component of the mitochondrial permeability transition pore. Interference with the normal functions of these proteins results in mitochondrial injury, such as energy dyshomeostasis, production of reactive oxygen species, membrane permeability alteration and so on. This review explores the Aβ generation and location in mitochondria. The mitochondrial injury induced by the interaction between Aβ and its targets are also discussed.展开更多
基金supported by the National Natural Science Foundation of China,Nos.81901267(to YY),82001263(to WXC),81901193(to HLZ)a grant from State Key Laboratory of Trauma,Burn and Combined Injury,No.SKLYQ202002(to YJC)+1 种基金a grant from Wuxi Municipal Health Commission No.2020ZHYB19(to YY)a grant from Wuxi Science and Technology Bureau,No.Y20212045(to LKY)。
文摘The mitochondrial permeability transition pore is a nonspecific transmembrane channel.Inhibition of mitochondrial permeability transition pore opening has been shown to alleviate mitochondrial swelling,calcium overload,and axonal degeneration.Cyclophilin D is an important component of the mitochondrial permeability transition pore.Whether cyclophilin D participates in mitochondrial impairment and axonal injury after intracerebral hemorrhage is not clear.In this study,we established mouse models of intracerebral hemorrhage in vivo by injection of autologous blood and oxyhemoglobin into the striatum in Thy1-YFP mice,in which pyramidal neurons and axons express yellow fluorescent protein.We also simulated intracerebral hemorrhage in vitro in PC12 cells using oxyhemoglobin.We found that axonal degeneration in the early stage of intracerebral hemorrhage depended on mitochondrial swelling induced by cyclophilin D activation and mitochondrial permeability transition pore opening.We further investigated the mechanism underlying the role of cyclophilin D in mouse models and PC12 cell models of intracerebral hemorrhage.We found that both cyclosporin A inhibition and short hairpin RNA interference of cyclophilin D reduced mitochondrial permeability transition pore opening and mitochondrial injury.In addition,inhibition of cyclophilin D and mitochondrial permeability transition pore opening protected corticospinal tract integrity and alleviated motor dysfunction caused by intracerebral hemorrhage.Our findings suggest that cyclophilin D is used as a key mediator of axonal degeneration after intracerebral hemorrhage;inhibition of cyclophilin D expression can protect mitochondrial structure and function and further alleviate corticospinal tract injury and motor dysfunction after intracerebral hemorrhage.Our findings provide a therapeutic target for preventing axonal degeneration of white matter injury and subsequent functional impairment in central nervous diseases.
基金supported by the National Natural Science Foundation of China(31660337)Special Aquatic Products Industry Technology System of Jiangxi(JXARS-10)+1 种基金Scientific and Technological Program of Jiangxi Province(KJLD12001,20152ACF60013 and 150166)Natural Science Foundation of Jiangxi Province(20122BAB204016)
文摘Cyclophilin D （referred to as HsCypD） was obtained from the freshwater pearl mussel （Hyriopsis schlegelil）. The full-length cDNA was 2 671 bp, encoding a protein consisting of 367 amino acids. HsCypD was determined to be a hydrophilic intracellular protein with 10 phosphorylation sites and four tetratricopeptide repeat （TPR） domains, but no signal peptide. The core sequence region YKGCIFHRIIKDFMVQGG is highly conserved in vertebrates and invertebrates. Phylogenetic tree analysis indicated that CypD from all species had a common origin, and HsCypD had the closest phylogenetic relationship with CypD from Lottia gigantea. The constitutive mRNA expression levels of HsCypD exhibited tissue-specific patterns, with the highest level detected in the intestines, followed by the gonads, and the lowest expression found in the hemocytes.
基金Independently cultivates innovation team program of Jinan,China,Grant/Award Number:2021GXRC048Shandong Provincial Natural Science Foundation,Grant/Award Number:ZR2020ZD14+1 种基金National Natural Science Foundation of China,Grant/Award Number:82270922National Key Research and Development Program of China,Grant/Award Number:2022YFA0806100。
文摘Background:Liver ischemia/reperfusion(I/R)injury is a complex and multifactorial pathophysiological process.It is well recognized that the membrane permeability transition pore(mPTP)opening of mitochondria plays a crucial role in cell death after I/R injury.Cyclophilin D(CypD)is a critical positive regulator of mPTP.However,the effect of CypD on the pathogenesis of liver I/R injury and whether CypD is a potential therapeutic target are still unclear.Methods:We constructed liver-specific CypD knockout and AAV8-peptidyl prolyl isomerase F(PPIF)overexpression mice.Then,a 70%liver I/R injury model was established in mice,with 90 min of ischemia and 6 h of reperfusion.The liver function was detected by the level of serum glutamic pyruvic transaminase(alanine transaminase)and glutamic oxaloacetic transaminase(aspartate aminotransferase),the liver damage score and degree of necrosis were measured by hematoxylin and eosin(H&E)staining of liver tissues.Reactive oxygen species(ROS)staining,apoptosis,and autophagy-related molecules were used to detect apoptosis and autophagy during liver I/R.Results:The liver-specific knockout of CypD alleviated necrosis and dysfunction in liver I/R injury,by reducing the excessive production of ROS,and inhibiting cell apoptosis and autophagy.On the contrary,overexpression of CypD exacerbated I/R-induced liver damage.Conclusion:We found that the downregulation of CypD expression alleviated liver I/R injury by reducing apoptosis and autophagy through caspase-3/Beclin1 crosstalk;in contrast,the upregulation of CypD expression aggravated liver I/R injury.Therefore,interfering with the expression of CypD seems to be a promising treatment for liver I/R injury.
文摘p53＇s apoptotic program consists of transcription-dependent and transcription-independent pathways. In the latter, physical interactions between mitochondrial p53 and anti- and pro-apoptotic members of the Bcl2 family of mitochondrial permeability regulators are central. Using isogenic cell systems with defined deficiencies, we characterize in detail how mitochondrial p53 contributes to mitochondrial permeabilization, to what extent its action depends on other key Bcl2 family members and define its release activity. We show that mitochondrial p53 is highly efficient in inducing the release of soluble and insoluble apoptogenic factors by severely disrupting outer and inner mitochondrial membrane integrity. This action is associated with wild-type p53-induced oligomerization of Bax, Bak and VDAC and the formation of a stress-induced endogenous complex between p53 and cyclophilin D, normally located at the inner membrane. Tumor-derived p53 mutants are deficient in activating the Bax/Bak lipid pore. These actions are independent of Puma and Bax. Importantly, the latter distinguishes the mitochondrial from the cytosolic p53 death pathway.
基金supported by a grant from the Kentucky Spinal Cord and Head Injury Research Trust
文摘The mitochondrion serves many functions in the central nervous system （CNS） and other organs beyond the well-recognized role of adenosine triphosphate （ATP） production. This includes calcium-dependent cell signaling, regulation of gene expression, synthesis and release of cytotoxic reactive oxygen species, and the release of cytochrome c and other apoptotic cell death factors. Traumatic injury to the CNS results in a rapid and, in some cases, sustained loss of mitochondrial function. One consequence of compromised mitochondrial function is induction of the mitochondrial permeability transition （mPT） state due to formation of the cyclosporine A sensitive permeability transition pore （mPTP）. In this mini-review, we summarize evidence supporting the involvement of the mPTP as a mediator of mitochondrial and cellular demise following CNS traumatic injury and discuss the beneficial effects and limitations of the current ex- perimental strategies targeting the mPTP.
文摘The β-amyloid protein (Aβ) has long been considered to associate with Alzheimer’s disease (AD). In addition, groups of evidence show that the soluble intracellular Aβ plays an important role in the disease development. The mitochondrial dysfunction induced by Aβ accumulation is a main pathologic process in early stage of AD. Matured Aβ is imported into the mitochondria through an unclear route. Once inside the mitochondria, Aβ is able to interact with a number of targets, including amyloid-binding alcohol dehydrogenase (ABAD) and cyclophilin D (CypD), which is a component of the mitochondrial permeability transition pore. Interference with the normal functions of these proteins results in mitochondrial injury, such as energy dyshomeostasis, production of reactive oxygen species, membrane permeability alteration and so on. This review explores the Aβ generation and location in mitochondria. The mitochondrial injury induced by the interaction between Aβ and its targets are also discussed.
