Objective Keshan disease(KD)is a myocardial mitochondrial disease closely related to insufficient selenium(Se)and protein intake.PTEN induced putative kinase 1(PINK1)/Parkin mediated mitochondrial autophagy regulates ...Objective Keshan disease(KD)is a myocardial mitochondrial disease closely related to insufficient selenium(Se)and protein intake.PTEN induced putative kinase 1(PINK1)/Parkin mediated mitochondrial autophagy regulates various physiological and pathological processes in the body.This study aimed to elucidate the relationship between PINK1/Parkin-regulated mitochondrial autophagy and KD-related myocardial injury.Methods A low Se and low protein animal model was established.One hundred Wistar rats were randomly divided into 5 groups(control group,low Se group,low protein group,low Se+low protein group,and corn from KD area group).The JC-1 method was used to detect the mitochondrial membrane potential(MMP).ELISA was used to detect serum creatine kinase MB(CK-MB),cardiac troponin I(cTnI),and mitochondrial-glutamicoxalacetic transaminase(M-GOT)levels.RT-PCR and Western blot analysis were used to detect the expression of PINK1,Parkin,sequestome 1(P62),and microtubule-associated proteins1A/1B light chain 3B(MAP1LC3B).Results The MMP was significantly decreased and the activity of CK-MB,cTnI,and M-GOT significantly increased in each experimental group(low Se group,low protein group,low Se+low protein group and corn from KD area group)compared with the control group(P<0.05 for all).The mRNA and protein expression levels of PINK1,Parkin and MAP1LC3B were profoundly increased,and those of P62 markedly decreased in the experimental groups compared with the control group(P<0.05 for all).Conclusion Low Se and low protein levels exacerbate myocardial damage in KD by affecting the PINK1/Parkin-mediated mitochondrial autophagy pathway.展开更多
目的探讨糖原合成酶激酶3β(glycogen synthase kinase 3β,GSK3β)/线粒体分裂蛋白1(fission protein 1,Fis1)信号通路在甲基乙二醛(methylglyoxal,MG)诱导成骨细胞凋亡中的作用及机制。方法采用LiCl作为GSK3β抑制剂,将细胞随机分为4...目的探讨糖原合成酶激酶3β(glycogen synthase kinase 3β,GSK3β)/线粒体分裂蛋白1(fission protein 1,Fis1)信号通路在甲基乙二醛(methylglyoxal,MG)诱导成骨细胞凋亡中的作用及机制。方法采用LiCl作为GSK3β抑制剂,将细胞随机分为4组,即对照组、MG组、LiCl组和LiCl+MG组。采用MTT法检测细胞增殖活性,Tunel染色法分析细胞凋亡情况,Western blot法检测GSK3β、Fis1蛋白表达水平,MitoTracker Deep Red染色法分析线粒体形态。结果MTT法检测结果表明,MG抑制了成骨细胞增殖活性。Tunel染色法检测结果显示,MG诱导成骨细胞凋亡。Western blot法检测结果表明,MG处理后GSK3β蛋白磷酸化水平降低,Fis1蛋白表达水平增加。MitoTracker Deep Red染色法分析结果显示,MG处理后线粒体呈碎片化。在加入GSK3β抑制剂LiCl干预后,与MG组比较,其显著恢复了MG抑制的细胞增殖活性、减少细胞凋亡,同时GSK3β蛋白磷酸化水平升高,Fis1蛋白表达水平降低,并且恢复了线粒体形态。结论MG可能通过调控GSK3β/Fis1信号通路促进线粒体分裂增加,诱导成骨细胞凋亡。展开更多
Mitochondria undergo morphological changes during spermatogenesis in some animals.The mechanism and role of mitochondrial morphology regulation,however,remain somewhat unclear.In this study,we analyzed the molecular c...Mitochondria undergo morphological changes during spermatogenesis in some animals.The mechanism and role of mitochondrial morphology regulation,however,remain somewhat unclear.In this study,we analyzed the molecular characteristics,expression dynamics and subcellular localization of optic atrophy protein 1(OPA1),a mitochondrial fusion and cristae maintenance-related protein,to reveal the possible regulatory mechanisms underlying mitochondrial morphology in Phascolosoma esculenta spermiogenesis.The full-length cDNA of the P.esculenta opa1 gene(Pe-opa1)is 3743 bp in length and encodes 975 amino acids.The Pe-OPA1 protein is highly conservative and includes a transmembrane domain,a GTPase domain,two helical bundle domains,and a lipid-interacting stalk.Gene and protein expression was higher in the coelomic fluid(a site of spermatid development)of male P.esculenta and increased first and then decreased from March to December.Moreover,their expression during the breeding stage was significantly higher than during the non-breeding stage,suggesting that Pe-OPA1 is involved in P.esculenta reproduction.The Pe-OPA1 protein was more abundant in components consisting of many spermatids than in components without,indicating that Pe-OPA1 mainly plays a role in the spermatid in coelomic fluid.Moreover,Pe-OPA1 was mainly detected in the spermatid mitochondria.Immunofluorescence experiments showed that the Pe-OPA1 are constitutively expressed and co-localized with mitochondria during spermiogenesis,suggesting its involvement in P.esculenta spermiogenesis.These results provide evidence for Pe-OPA1's involvement in the regulation of mitochondrial morphology during spermiogenesis.展开更多
Hypoxic-ischemic injury is a common pathological dysfunction in clinical settings.Mitochondria are sensitive organelles that are readily damaged following ischemia and hypoxia.Dynamin-related protein 1(Drp1)regulates ...Hypoxic-ischemic injury is a common pathological dysfunction in clinical settings.Mitochondria are sensitive organelles that are readily damaged following ischemia and hypoxia.Dynamin-related protein 1(Drp1)regulates mitochondrial quality and cellular functions via its oligomeric changes and multiple modifications,which plays a role in mediating the induction of multiple organ damage during hypoxic-ischemic injury.However,there is active controversy and gaps in knowledge regarding the modification,protein interaction,and functions of Drp1,which both hinder and promote development of Drp1 as a novel therapeutic target.Here,we summarize recent findings on the oligomeric changes,modification types,and protein interactions of Drp1 in various hypoxic-ischemic diseases,as well as the Drp1-mediated regulation of mitochondrial quality and cell functions following ischemia and hypoxia.Additionally,potential clinical translation prospects for targeting Drp1 are discussed.This review provides new ideas and targets for proactive interventions on multiple organ damage induced by various hypoxic-ischemic diseases.展开更多
BACKGROUND Intestinal ischemia reperfusion(I/R)occurs in various diseases,such as trauma and intestinal transplantation.Excessive reactive oxygen species(ROS)accumulation and subsequent apoptotic cell death in intesti...BACKGROUND Intestinal ischemia reperfusion(I/R)occurs in various diseases,such as trauma and intestinal transplantation.Excessive reactive oxygen species(ROS)accumulation and subsequent apoptotic cell death in intestinal epithelia are important causes of I/R injury.PTEN-induced putative kinase 1(PINK1)and phosphorylation of dynamin-related protein 1(DRP1)are critical regulators of ROS and apoptosis.However,the correlation of PINK1 and DRP1 and their function in intestinal I/R injury have not been investigated.Thus,examining the PINK1/DRP1 pathway may help to identify a protective strategy and improve the patient prognosis.AIM To clarify the mechanism of the PINK1/DRP1 pathway in intestinal I/R injury.METHODS Male C57BL/6 mice were used to generate an intestinal I/R model via superior mesenteric artery occlusion followed by reperfusion.Chiu’s score was used to evaluate intestinal mucosa damage.The mitochondrial fission inhibitor mdivi-1 was administered by intraperitoneal injection.Caco-2 cells were incubated in vitro in hypoxia/reoxygenation conditions.Small interfering RNAs and overexpression plasmids were transfected to regulate PINK1 expression.The protein expression levels of PINK1,DRP1,p-DRP1 and cleaved caspase 3 were measured by Western blotting.Cell viability was evaluated using a Cell Counting Kit-8 assay and cell apoptosis was analyzed by TUNEL staining.Mitochondrial fission and ROS were tested by MitoTracker and MitoSOX respectively.RESULTS Intestinal I/R and Caco-2 cell hypoxia/reoxygenation decreased the expression of PINK1 and p-DRP1 Ser637.Pretreatment with mdivi-1 inhibited mitochondrial fission,ROS generation,and apoptosis and ameliorated cell injury in intestinal I/R.Upon PINK1 knockdown or overexpression in vitro,we found that p-DRP1 Ser637 expression and DRP1 recruitment to the mitochondria were associated with PINK1.Furthermore,we verified the physical combination of PINK1 and p-DRP1 Ser637.CONCLUSION PINK1 is correlated with mitochondrial fission and apoptosis by regulating DRP1 phosphorylation in intestinal I/R.These results suggest that the PINK1/DRP1 pathway is involved in intestinal I/R injury,and provide a new approach for prevention and treatment.展开更多
目的:研究线粒体分裂抑制剂1(Mdivi-1)在实验性自身免疫性脑脊髓炎(EAE)小鼠髓鞘保护中的作用,探讨Mdivi-1抑制髓鞘变性的机制。方法:小鼠经髓磷脂少突胶质细胞糖蛋白第35~55位肽段(MOG35-55)免疫后,随机分为DMSO模型组和Mdivi-1干预组...目的:研究线粒体分裂抑制剂1(Mdivi-1)在实验性自身免疫性脑脊髓炎(EAE)小鼠髓鞘保护中的作用,探讨Mdivi-1抑制髓鞘变性的机制。方法:小鼠经髓磷脂少突胶质细胞糖蛋白第35~55位肽段(MOG35-55)免疫后,随机分为DMSO模型组和Mdivi-1干预组。于免疫后第28天处死小鼠,行Luxol fast blue染色分析髓鞘丢失情况,免疫荧光染色和TUNEL染色小鼠脊髓组织和体外细胞实验分析Mdivi-1髓鞘保护机制。结果:与DMSO模型组比较,Mdivi-1处理明显减少EAE小鼠脊髓组织白质区髓鞘丢失,减少少突胶质细胞凋亡及线粒体凋亡相关蛋白cleaved caspase-3、caspase-9、cytochrome C和Bax的表达;体外MO3.13少突胶质细胞培养实验发现,Mdivi-1可以明显阻止星形孢菌素(staurosporine)处理诱导的线粒体膜电位去极化,减轻细胞损伤,增强细胞活力。结论:Mdivi-1可能通过抑制少突胶质细胞线粒体相关凋亡信号通路发挥髓鞘保护作用。展开更多
Divisions at the periphery and midzone of mitochondria are two fission signatures that determine the fate of mitochondria and cells.Pharmacological induction of excessively asymmetric mitofissionassociated cell death(...Divisions at the periphery and midzone of mitochondria are two fission signatures that determine the fate of mitochondria and cells.Pharmacological induction of excessively asymmetric mitofissionassociated cell death(MFAD)by switching the scission position from the mitochondrial midzone to the periphery represents a promising strategy for anticancer therapy.By screening a series of paninhibitors,we identified pracinostat,a pan-histone deacetylase(HDAC)inhibitor,as a novel MFAD inducer,that exhibited a significant anticancer effect on colorectal cancer(CRC)in vivo and in vitro.Pracinostat increased the expression of cyclin-dependent kinase 5(CDK5)and induced its acetylation at residue lysine 33,accelerating the formation of complex CDK5/CDK5 regulatory subunit 1 and dynaminrelated protein 1(Drp1)-mediated mitochondrial peripheral fission.CRC cells with high level of CDK5(CDK5-high)displayed midzone mitochondrial division that was associated with oncogenic phenotype,but treatment with pracinostat led to a lethal increase in the already-elevated level of CDK5 in the CRC cells.Mechanistically,pracinostat switched the scission position from the mitochondrial midzone to the periphery by improving the binding of Drp1 from mitochondrial fission factor(MFF)to mitochondrial fission 1 protein(FIS1).Thus,our results revealed the anticancer mechanism of HDACi pracinostat in CRC via activating CDK5-Drp1 signaling to cause selective MFAD of those CDK5-high tumor cells,which implicates a new paradigm to develop potential therapeutic strategies for CRC treatment.展开更多
Mitochondrial dysfunction is a significant pathological alte ration that occurs in Parkinson's disease(PD),and the Thr61lle(T61I)mutation in coiled-coil helix coiled-coil helix domain containing 2(CHCHD2),a crucia...Mitochondrial dysfunction is a significant pathological alte ration that occurs in Parkinson's disease(PD),and the Thr61lle(T61I)mutation in coiled-coil helix coiled-coil helix domain containing 2(CHCHD2),a crucial mitochondrial protein,has been reported to cause Parkinson's disease.FIFO-ATPase participates in the synthesis of cellular adenosine triphosphate(ATP)and plays a central role in mitochondrial energy metabolism.However,the specific roles of wild-type(WT)CHCHD2 and T611-mutant CHCHD2 in regulating F1FO-ATPase activity in Parkinson's disease,as well as whether CHCHD2 or CHCHD2 T61I affects mitochondrial function through regulating F1FO-ATPase activity,remain unclea r.Therefore,in this study,we expressed WT CHCHD2 and T61l-mutant CHCHD2 in an MPP^(+)-induced SH-SY5Y cell model of PD.We found that CHCHD2 protected mitochondria from developing MPP^(+)-induced dysfunction.Under normal conditions,ove rexpression of WT CHCHD2 promoted F1FO-ATPase assembly,while T61I-mutant CHCHD2 appeared to have lost the ability to regulate F1FO-ATPase assembly.In addition,mass spectrometry and immunoprecipitation showed that there was an interaction between CHCHD2 and F1FO-ATPase.Three weeks after transfection with AAV-CHCHD2 T61I,we intraperitoneally injected 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine into mice to establish an animal model of chronic Parkinson's disease and found that exogenous expression of the mutant protein worsened the behavioral deficits and dopaminergic neurodegeneration seen in this model.These findings suggest that WT CHCHD2 can alleviate mitochondrial dysfunction in PD by maintaining F1F0-ATPase structure and function.展开更多
OBJECTIVE To elucidate the molecular mechanism and the anti-breast cancer effect of polyphyllinⅠ,which is a natural compound extracted from Rhizoma of Paris polyphyllin.METHODS Human breast cancer cells were treated ...OBJECTIVE To elucidate the molecular mechanism and the anti-breast cancer effect of polyphyllinⅠ,which is a natural compound extracted from Rhizoma of Paris polyphyllin.METHODS Human breast cancer cells were treated with polyphyllinⅠ,after which DRP1-dependent mitochondrial fission and apoptosis,mitophagy and PINK1/PARK2 pathway were evaluated.A genetic approach was employed to determine how knockdown of PINK1 with sh RNA regulates polyphyllinⅠ-induced mitophagy and apoptosis.The inhibitory effect of polyphyllinⅠon tumor growth in a breast cancer cell xenograft mouse model was also examined.RESULTS PolyphyllinⅠenhanced the stabilization of full-length PINK1at the mitochondrial surface,leading to PARK2 recruitment to mitochondria,and culminating in mitophagy.PolyphyllinⅠalso induced dephosphorylation of DRP1 at Ser637 and mitochondrial translocation of DRP1,leading to mitochondrial fission and apoptosis.Knockdown of PINK1 evidently suppressed mitophagy stimulated by polyphyllinⅠ,and markedly enhanced DRP1-dependent mitochondrial fission and apoptosis induced by polyphyl inⅠ.Furthermore,suppression of DRP1 by mdivi-1 or sh RNA inhibits PINK1 knockdown-mediated mitochondrial fragmentation and apoptosis in response to polyphyllinⅠtreatment,suggesting that depletion of PINK1 lead to mitochondrial fragmentation due to excessive fission.Our in vivo study also showed that knockdown of PINK1potentiated polyphyllinⅠ-mediated inhibition of tumor growth in a breast cancer cell xenograft mouse model.CONCLUSION Our study provides a mechanism to support the role of PINK1 in the regulation of polyphyl inⅠ-induced mitophagy and apoptosis,and suggest polyphylinⅠas a potential drug for treatment of breast cancer.展开更多
Objective: To explore the mechanisms of microRNA-150, cyclin B1 and mitochondrial-associated protein 2 in regulating the apoptosis and inhibiting the invasion and migration of Huh-7 cells. Methods: Huh-7 cells were di...Objective: To explore the mechanisms of microRNA-150, cyclin B1 and mitochondrial-associated protein 2 in regulating the apoptosis and inhibiting the invasion and migration of Huh-7 cells. Methods: Huh-7 cells were divided into the control group, the negative control group (NC group) and the miR-150 overexpression group (mimic group). The miR-150 overexpressing cell line was constructed by plasmid transfection. The cell viability and apoptosis were detected by cell counting kit-8 and flow cytometry. The cell migration and invasion capacity were measured by cell wound scratch assay and Transwell. The levels of miRNA and mRNA were detected by real-time quantitative polymerase chain reaction and the relative expression levels of proteins were detected by Western blot. Results: MiR-150 significantly inhibited the cell viability of Huh-7 and promoted its apoptosis (P<0.01). After 24 h of cultivation, the mobility of the control group and the NC group were (83.54±4.66)%and (85.57±4.74)%, respectively. The mobility of the mimic group was (49.63±3.78)%, which was significantly lower than that of the control group and the NC group (P<0.01). After 24 h of cultivation, the invasive rate of the control group and the NC group were (100.56±2.87)%and (101.63±3.74)%, respectively, and the invasive rate of mimic group was (51.63±5.32)%, which was significantly lower than that of the control group and the NC group (P<0.01). The expression levels of cyclin B1 protein and mRNA in the mimic group were significantly lower than those in the control group and the NC group (P<0.01), and the level of mitochondrial-associated protein 2 in the mimic group was significantly higher than that in the control group and the NC group (P<0.01). Conclusions: MiR-150 may inhibit the proliferation, migration, invasion and apoptosis of hepatoma carcinoma cell by regulating cyclin B1 or up-regulating mitochondrial-associated protein 2 levels.展开更多
基金supported by the Natural Science Foundation of Heilongjiang Province(No.LH2021H009).
文摘Objective Keshan disease(KD)is a myocardial mitochondrial disease closely related to insufficient selenium(Se)and protein intake.PTEN induced putative kinase 1(PINK1)/Parkin mediated mitochondrial autophagy regulates various physiological and pathological processes in the body.This study aimed to elucidate the relationship between PINK1/Parkin-regulated mitochondrial autophagy and KD-related myocardial injury.Methods A low Se and low protein animal model was established.One hundred Wistar rats were randomly divided into 5 groups(control group,low Se group,low protein group,low Se+low protein group,and corn from KD area group).The JC-1 method was used to detect the mitochondrial membrane potential(MMP).ELISA was used to detect serum creatine kinase MB(CK-MB),cardiac troponin I(cTnI),and mitochondrial-glutamicoxalacetic transaminase(M-GOT)levels.RT-PCR and Western blot analysis were used to detect the expression of PINK1,Parkin,sequestome 1(P62),and microtubule-associated proteins1A/1B light chain 3B(MAP1LC3B).Results The MMP was significantly decreased and the activity of CK-MB,cTnI,and M-GOT significantly increased in each experimental group(low Se group,low protein group,low Se+low protein group and corn from KD area group)compared with the control group(P<0.05 for all).The mRNA and protein expression levels of PINK1,Parkin and MAP1LC3B were profoundly increased,and those of P62 markedly decreased in the experimental groups compared with the control group(P<0.05 for all).Conclusion Low Se and low protein levels exacerbate myocardial damage in KD by affecting the PINK1/Parkin-mediated mitochondrial autophagy pathway.
文摘目的探讨糖原合成酶激酶3β(glycogen synthase kinase 3β,GSK3β)/线粒体分裂蛋白1(fission protein 1,Fis1)信号通路在甲基乙二醛(methylglyoxal,MG)诱导成骨细胞凋亡中的作用及机制。方法采用LiCl作为GSK3β抑制剂,将细胞随机分为4组,即对照组、MG组、LiCl组和LiCl+MG组。采用MTT法检测细胞增殖活性,Tunel染色法分析细胞凋亡情况,Western blot法检测GSK3β、Fis1蛋白表达水平,MitoTracker Deep Red染色法分析线粒体形态。结果MTT法检测结果表明,MG抑制了成骨细胞增殖活性。Tunel染色法检测结果显示,MG诱导成骨细胞凋亡。Western blot法检测结果表明,MG处理后GSK3β蛋白磷酸化水平降低,Fis1蛋白表达水平增加。MitoTracker Deep Red染色法分析结果显示,MG处理后线粒体呈碎片化。在加入GSK3β抑制剂LiCl干预后,与MG组比较,其显著恢复了MG抑制的细胞增殖活性、减少细胞凋亡,同时GSK3β蛋白磷酸化水平升高,Fis1蛋白表达水平降低,并且恢复了线粒体形态。结论MG可能通过调控GSK3β/Fis1信号通路促进线粒体分裂增加,诱导成骨细胞凋亡。
基金the Ningbo Science and Technology Plan Projects(Nos.2019B10016,2016C10004)the Major Science and Technology Projects in Zhejiang Province(No.2011C12013)+1 种基金the Natural Science Foundation of Zhejiang Province(No.LY18C190007)the Collaborative Innovation Center for Zhejiang Marine High-efficiency and Healthy Aquaculture,the K.C.Wong Magna Fund in Ningbo University。
文摘Mitochondria undergo morphological changes during spermatogenesis in some animals.The mechanism and role of mitochondrial morphology regulation,however,remain somewhat unclear.In this study,we analyzed the molecular characteristics,expression dynamics and subcellular localization of optic atrophy protein 1(OPA1),a mitochondrial fusion and cristae maintenance-related protein,to reveal the possible regulatory mechanisms underlying mitochondrial morphology in Phascolosoma esculenta spermiogenesis.The full-length cDNA of the P.esculenta opa1 gene(Pe-opa1)is 3743 bp in length and encodes 975 amino acids.The Pe-OPA1 protein is highly conservative and includes a transmembrane domain,a GTPase domain,two helical bundle domains,and a lipid-interacting stalk.Gene and protein expression was higher in the coelomic fluid(a site of spermatid development)of male P.esculenta and increased first and then decreased from March to December.Moreover,their expression during the breeding stage was significantly higher than during the non-breeding stage,suggesting that Pe-OPA1 is involved in P.esculenta reproduction.The Pe-OPA1 protein was more abundant in components consisting of many spermatids than in components without,indicating that Pe-OPA1 mainly plays a role in the spermatid in coelomic fluid.Moreover,Pe-OPA1 was mainly detected in the spermatid mitochondria.Immunofluorescence experiments showed that the Pe-OPA1 are constitutively expressed and co-localized with mitochondria during spermiogenesis,suggesting its involvement in P.esculenta spermiogenesis.These results provide evidence for Pe-OPA1's involvement in the regulation of mitochondrial morphology during spermiogenesis.
基金This work was supported by the National Natural Science Foundation of China(82272252,82270378)the Senior Medical Talents Program of Chongqing for Young and Middle-agedthe Kuanren Talents Program of the Second Affiliated Hospital of Chongqing Medical University.
文摘Hypoxic-ischemic injury is a common pathological dysfunction in clinical settings.Mitochondria are sensitive organelles that are readily damaged following ischemia and hypoxia.Dynamin-related protein 1(Drp1)regulates mitochondrial quality and cellular functions via its oligomeric changes and multiple modifications,which plays a role in mediating the induction of multiple organ damage during hypoxic-ischemic injury.However,there is active controversy and gaps in knowledge regarding the modification,protein interaction,and functions of Drp1,which both hinder and promote development of Drp1 as a novel therapeutic target.Here,we summarize recent findings on the oligomeric changes,modification types,and protein interactions of Drp1 in various hypoxic-ischemic diseases,as well as the Drp1-mediated regulation of mitochondrial quality and cell functions following ischemia and hypoxia.Additionally,potential clinical translation prospects for targeting Drp1 are discussed.This review provides new ideas and targets for proactive interventions on multiple organ damage induced by various hypoxic-ischemic diseases.
基金the National Natural Science Foundation of China,No.81679154,No.81871547.
文摘BACKGROUND Intestinal ischemia reperfusion(I/R)occurs in various diseases,such as trauma and intestinal transplantation.Excessive reactive oxygen species(ROS)accumulation and subsequent apoptotic cell death in intestinal epithelia are important causes of I/R injury.PTEN-induced putative kinase 1(PINK1)and phosphorylation of dynamin-related protein 1(DRP1)are critical regulators of ROS and apoptosis.However,the correlation of PINK1 and DRP1 and their function in intestinal I/R injury have not been investigated.Thus,examining the PINK1/DRP1 pathway may help to identify a protective strategy and improve the patient prognosis.AIM To clarify the mechanism of the PINK1/DRP1 pathway in intestinal I/R injury.METHODS Male C57BL/6 mice were used to generate an intestinal I/R model via superior mesenteric artery occlusion followed by reperfusion.Chiu’s score was used to evaluate intestinal mucosa damage.The mitochondrial fission inhibitor mdivi-1 was administered by intraperitoneal injection.Caco-2 cells were incubated in vitro in hypoxia/reoxygenation conditions.Small interfering RNAs and overexpression plasmids were transfected to regulate PINK1 expression.The protein expression levels of PINK1,DRP1,p-DRP1 and cleaved caspase 3 were measured by Western blotting.Cell viability was evaluated using a Cell Counting Kit-8 assay and cell apoptosis was analyzed by TUNEL staining.Mitochondrial fission and ROS were tested by MitoTracker and MitoSOX respectively.RESULTS Intestinal I/R and Caco-2 cell hypoxia/reoxygenation decreased the expression of PINK1 and p-DRP1 Ser637.Pretreatment with mdivi-1 inhibited mitochondrial fission,ROS generation,and apoptosis and ameliorated cell injury in intestinal I/R.Upon PINK1 knockdown or overexpression in vitro,we found that p-DRP1 Ser637 expression and DRP1 recruitment to the mitochondria were associated with PINK1.Furthermore,we verified the physical combination of PINK1 and p-DRP1 Ser637.CONCLUSION PINK1 is correlated with mitochondrial fission and apoptosis by regulating DRP1 phosphorylation in intestinal I/R.These results suggest that the PINK1/DRP1 pathway is involved in intestinal I/R injury,and provide a new approach for prevention and treatment.
文摘目的:研究线粒体分裂抑制剂1(Mdivi-1)在实验性自身免疫性脑脊髓炎(EAE)小鼠髓鞘保护中的作用,探讨Mdivi-1抑制髓鞘变性的机制。方法:小鼠经髓磷脂少突胶质细胞糖蛋白第35~55位肽段(MOG35-55)免疫后,随机分为DMSO模型组和Mdivi-1干预组。于免疫后第28天处死小鼠,行Luxol fast blue染色分析髓鞘丢失情况,免疫荧光染色和TUNEL染色小鼠脊髓组织和体外细胞实验分析Mdivi-1髓鞘保护机制。结果:与DMSO模型组比较,Mdivi-1处理明显减少EAE小鼠脊髓组织白质区髓鞘丢失,减少少突胶质细胞凋亡及线粒体凋亡相关蛋白cleaved caspase-3、caspase-9、cytochrome C和Bax的表达;体外MO3.13少突胶质细胞培养实验发现,Mdivi-1可以明显阻止星形孢菌素(staurosporine)处理诱导的线粒体膜电位去极化,减轻细胞损伤,增强细胞活力。结论:Mdivi-1可能通过抑制少突胶质细胞线粒体相关凋亡信号通路发挥髓鞘保护作用。
基金supported by the National Natural Science Foundation of China(Grant Nos.:82103208,and 82002948)the Guangdong Basic and Applied Basic Research Foundation(Grant Nos.:2022A1515220212,and 2023A1515030115)+1 种基金National Key R&D Program of China(Grant No.:2020YFE0202200)Jinan University National College Students'Innovation and Entrepreneurship Training Program(Program No.:202110559085).
文摘Divisions at the periphery and midzone of mitochondria are two fission signatures that determine the fate of mitochondria and cells.Pharmacological induction of excessively asymmetric mitofissionassociated cell death(MFAD)by switching the scission position from the mitochondrial midzone to the periphery represents a promising strategy for anticancer therapy.By screening a series of paninhibitors,we identified pracinostat,a pan-histone deacetylase(HDAC)inhibitor,as a novel MFAD inducer,that exhibited a significant anticancer effect on colorectal cancer(CRC)in vivo and in vitro.Pracinostat increased the expression of cyclin-dependent kinase 5(CDK5)and induced its acetylation at residue lysine 33,accelerating the formation of complex CDK5/CDK5 regulatory subunit 1 and dynaminrelated protein 1(Drp1)-mediated mitochondrial peripheral fission.CRC cells with high level of CDK5(CDK5-high)displayed midzone mitochondrial division that was associated with oncogenic phenotype,but treatment with pracinostat led to a lethal increase in the already-elevated level of CDK5 in the CRC cells.Mechanistically,pracinostat switched the scission position from the mitochondrial midzone to the periphery by improving the binding of Drp1 from mitochondrial fission factor(MFF)to mitochondrial fission 1 protein(FIS1).Thus,our results revealed the anticancer mechanism of HDACi pracinostat in CRC via activating CDK5-Drp1 signaling to cause selective MFAD of those CDK5-high tumor cells,which implicates a new paradigm to develop potential therapeutic strategies for CRC treatment.
基金supported by the National Natural Science Foundation of China(Youth Program),No.81901282(to XC)the National Natural Science Foundation of China,Nos.81401416(to PX),81870992(to PX),81870856(to XC and MZ)+3 种基金Guangdong Basic and Applied Basic Research Foundation the Science Foundation,No.2019A1515011189(to XC)Central Government Guiding Local Science and Technology Development Projects,No.ZYYD2022C17(to PX)Key Project of Guangzhou Health Commission,No.2019-ZD-09(to PX)Science and Technology Planning Project of Guangzhou,Nos.202102020029(to XC),202102010010(to PX)。
文摘Mitochondrial dysfunction is a significant pathological alte ration that occurs in Parkinson's disease(PD),and the Thr61lle(T61I)mutation in coiled-coil helix coiled-coil helix domain containing 2(CHCHD2),a crucial mitochondrial protein,has been reported to cause Parkinson's disease.FIFO-ATPase participates in the synthesis of cellular adenosine triphosphate(ATP)and plays a central role in mitochondrial energy metabolism.However,the specific roles of wild-type(WT)CHCHD2 and T611-mutant CHCHD2 in regulating F1FO-ATPase activity in Parkinson's disease,as well as whether CHCHD2 or CHCHD2 T61I affects mitochondrial function through regulating F1FO-ATPase activity,remain unclea r.Therefore,in this study,we expressed WT CHCHD2 and T61l-mutant CHCHD2 in an MPP^(+)-induced SH-SY5Y cell model of PD.We found that CHCHD2 protected mitochondria from developing MPP^(+)-induced dysfunction.Under normal conditions,ove rexpression of WT CHCHD2 promoted F1FO-ATPase assembly,while T61I-mutant CHCHD2 appeared to have lost the ability to regulate F1FO-ATPase assembly.In addition,mass spectrometry and immunoprecipitation showed that there was an interaction between CHCHD2 and F1FO-ATPase.Three weeks after transfection with AAV-CHCHD2 T61I,we intraperitoneally injected 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine into mice to establish an animal model of chronic Parkinson's disease and found that exogenous expression of the mutant protein worsened the behavioral deficits and dopaminergic neurodegeneration seen in this model.These findings suggest that WT CHCHD2 can alleviate mitochondrial dysfunction in PD by maintaining F1F0-ATPase structure and function.
基金The project supported by National Natural Science Foundation of China(81402970,81402202,81402013,81202869)
文摘OBJECTIVE To elucidate the molecular mechanism and the anti-breast cancer effect of polyphyllinⅠ,which is a natural compound extracted from Rhizoma of Paris polyphyllin.METHODS Human breast cancer cells were treated with polyphyllinⅠ,after which DRP1-dependent mitochondrial fission and apoptosis,mitophagy and PINK1/PARK2 pathway were evaluated.A genetic approach was employed to determine how knockdown of PINK1 with sh RNA regulates polyphyllinⅠ-induced mitophagy and apoptosis.The inhibitory effect of polyphyllinⅠon tumor growth in a breast cancer cell xenograft mouse model was also examined.RESULTS PolyphyllinⅠenhanced the stabilization of full-length PINK1at the mitochondrial surface,leading to PARK2 recruitment to mitochondria,and culminating in mitophagy.PolyphyllinⅠalso induced dephosphorylation of DRP1 at Ser637 and mitochondrial translocation of DRP1,leading to mitochondrial fission and apoptosis.Knockdown of PINK1 evidently suppressed mitophagy stimulated by polyphyllinⅠ,and markedly enhanced DRP1-dependent mitochondrial fission and apoptosis induced by polyphyl inⅠ.Furthermore,suppression of DRP1 by mdivi-1 or sh RNA inhibits PINK1 knockdown-mediated mitochondrial fragmentation and apoptosis in response to polyphyllinⅠtreatment,suggesting that depletion of PINK1 lead to mitochondrial fragmentation due to excessive fission.Our in vivo study also showed that knockdown of PINK1potentiated polyphyllinⅠ-mediated inhibition of tumor growth in a breast cancer cell xenograft mouse model.CONCLUSION Our study provides a mechanism to support the role of PINK1 in the regulation of polyphyl inⅠ-induced mitophagy and apoptosis,and suggest polyphylinⅠas a potential drug for treatment of breast cancer.
文摘Objective: To explore the mechanisms of microRNA-150, cyclin B1 and mitochondrial-associated protein 2 in regulating the apoptosis and inhibiting the invasion and migration of Huh-7 cells. Methods: Huh-7 cells were divided into the control group, the negative control group (NC group) and the miR-150 overexpression group (mimic group). The miR-150 overexpressing cell line was constructed by plasmid transfection. The cell viability and apoptosis were detected by cell counting kit-8 and flow cytometry. The cell migration and invasion capacity were measured by cell wound scratch assay and Transwell. The levels of miRNA and mRNA were detected by real-time quantitative polymerase chain reaction and the relative expression levels of proteins were detected by Western blot. Results: MiR-150 significantly inhibited the cell viability of Huh-7 and promoted its apoptosis (P<0.01). After 24 h of cultivation, the mobility of the control group and the NC group were (83.54±4.66)%and (85.57±4.74)%, respectively. The mobility of the mimic group was (49.63±3.78)%, which was significantly lower than that of the control group and the NC group (P<0.01). After 24 h of cultivation, the invasive rate of the control group and the NC group were (100.56±2.87)%and (101.63±3.74)%, respectively, and the invasive rate of mimic group was (51.63±5.32)%, which was significantly lower than that of the control group and the NC group (P<0.01). The expression levels of cyclin B1 protein and mRNA in the mimic group were significantly lower than those in the control group and the NC group (P<0.01), and the level of mitochondrial-associated protein 2 in the mimic group was significantly higher than that in the control group and the NC group (P<0.01). Conclusions: MiR-150 may inhibit the proliferation, migration, invasion and apoptosis of hepatoma carcinoma cell by regulating cyclin B1 or up-regulating mitochondrial-associated protein 2 levels.
