Pyruvate is a key intermediate at the branchpoint of anaerobic and aerobic energy metabolism. Its transport into the mitochondrial matrix is necessary prior to its decarboxylation into acetyl-CoA, which feeds the redu...Pyruvate is a key intermediate at the branchpoint of anaerobic and aerobic energy metabolism. Its transport into the mitochondrial matrix is necessary prior to its decarboxylation into acetyl-CoA, which feeds the reducing equivalent-generating tricarboxylic acid (TCA) cycle. Although the existence of specific carrier transport of cytosolic pyruvate into the mitochondria has been inferred from a myriad of studies, the identities of the mitochondrial pyruvate carrier (MPC) were only confirmed very recently. Identification of the MPC facilitated several other recent advances. These include the finding of MPC’s inhibition by the insulin-sensitizing drug family thiazolidinediones, how cells respond flexibly to a reduction in MPC functionality, as well as insights into how changes in MPC levels affect oncogenic potential of cancer cells. These new findings, discussed here in this brief review, have important implications in therapeutic approaches towards metabolic disorders and cancer.展开更多
Objective:This study aimed to evaluate the effects of mitochondrial pyruvate carrier(MPC)blockade on the sensitivity of detection and radiotherapy of prostate cancer(PCa).Methods:We investigated glycolysis reprogrammi...Objective:This study aimed to evaluate the effects of mitochondrial pyruvate carrier(MPC)blockade on the sensitivity of detection and radiotherapy of prostate cancer(PCa).Methods:We investigated glycolysis reprogramming and MPC changes in patients with PCa by using metabolic profiling,RNASeq,and tissue microarrays.Transient blockade of pyruvate influx into mitochondria was observed in cellular studies to detect its different effects on prostate carcinoma cells and benign prostate cells.Xenograft mouse models were injected with an MPC inhibitor to evaluate the sensitivity of 18F-fluorodeoxyglucose positron emission tomography with computed tomography and radiotherapy of PCa.Furthermore,the molecular mechanism of this different effect of transient blockage towards benign prostate cells and prostate cancer cells was studied in vitro.Results:MPC was elevated in PCa tissue compared with benign prostate tissue,but decreased during cancer progression.The transient blockade increased PCa cell proliferation while decreasing benign prostate cell proliferation,thus increasing the sensitivity of PCa cells to 18F-PET/CT(SUVavg,P=0.016;SUVmax,P=0.03)and radiotherapy(P<0.01).This differential effect of MPC on PCa and benign prostate cells was dependent on regulation by a VDAC1-MPC-mitochondrial homeostasis-glycolysis pathway.Conclusions:Blockade of pyruvate influx into mitochondria increased glycolysis levels in PCa but not in non-carcinoma prostate tissue.This transient blockage sensitized PCa to both detection and radiotherapy,thus indicating that glycolytic potential is a novel mechanism underlying PCa progression.The change in the mitochondrial pyruvate influx caused by transient MPC blockade provides a critical target for PCa diagnosis and treatment.展开更多
Abscisic acid （ABA） regulates ion channel activity and stomatal movements in response to drought and other stresses. Here, we show that the Arabidopsis thaliana gene NRGA1 is a putative mitochondrial pyruvate carrie...Abscisic acid （ABA） regulates ion channel activity and stomatal movements in response to drought and other stresses. Here, we show that the Arabidopsis thaliana gene NRGA1 is a putative mitochondrial pyruvate carrier which negatively regulates ABA-induced guard cell signaling. NRGA1 transcript was abundant in the A. thaliana leaf and par- ticularly in the guard cells, and its product was directed to the mitochondria. The heterologous co-expression of NRGA1 and AtMPC1 in yeast complemented a loss-of-function mitochondrial pyruvate carrier （MPC） mutant. The nrgal loss-of- function mutant was very sensitive to the presence of ABA in the context of stomatal movements, and exhibited a height- ened tolerance to drought stress. Disruption of NRGA1 gene resulted in increased ABA inhibition of inward K＋ currents and ABA activation of slow anion currents in guard cells. The nrgal/NRGA1 functional complementation lines restored the mutant＇s phenotypes. Furthermore, transgenic lines of constitutively overexpressing NRGA1 showed opposite stomatal responses, reduced drought tolerance, and ABA sensitivity of guard cell inward K＋ channel inhibition and anion channel activation. Our findings highlight a putative role for the mitochondrial pyruvate carrier in guard cell ABA signaling in response to drought.展开更多
目的探究抑制线粒体丙酮酸载体(mitochondrial pyruvate carrier,MPC)是否通过激活腺苷酸激活蛋白激酶(AMP-activated protein kinase,AMPK)-乙酰辅酶A羧化酶(acetyl CoA carboxylase,ACC)通路,改善棕榈酸(palmitic acid,PA)所致HepG2...目的探究抑制线粒体丙酮酸载体(mitochondrial pyruvate carrier,MPC)是否通过激活腺苷酸激活蛋白激酶(AMP-activated protein kinase,AMPK)-乙酰辅酶A羧化酶(acetyl CoA carboxylase,ACC)通路,改善棕榈酸(palmitic acid,PA)所致HepG2细胞脂肪变性情况。方法利用PA处理HepG2细胞作为高脂负荷模型组,实验分为正常对照组、模型组和MPC抑制组。油红O染色分析细胞的油脂蓄积情况。RT-PCR检测AMPK、ACC、CPT1A、SREBP1 mRNA表达水平。全自动蛋白分析仪检测AMPK、p-AMPK、ACC、p-ACC、SREBP1蛋白表达水平。结果PA可以诱导HepG2细胞胞质内聚集大量环状脂滴,降低p-AMPK、p-ACC蛋白表达水平,提高SREBP1基因以及蛋白表达水平。MPC抑制剂UK5099可以减少PA所致HepG2细胞胞质内脂滴数量,提高p-AMPK、p-ACC蛋白表达水平,降低SREBP1基因以及蛋白表达水平。结论体外抑制MPC可以明显改善PA所致HepG2细胞脂肪变性。激活AMPK-ACC信号通路,可能是MPC抑制剂防治非酒精性脂肪性肝病(non-alcoholic fatty liver disease,NAFLD)肝细胞脂肪变性的重要作用机制之一。展开更多
文摘Pyruvate is a key intermediate at the branchpoint of anaerobic and aerobic energy metabolism. Its transport into the mitochondrial matrix is necessary prior to its decarboxylation into acetyl-CoA, which feeds the reducing equivalent-generating tricarboxylic acid (TCA) cycle. Although the existence of specific carrier transport of cytosolic pyruvate into the mitochondria has been inferred from a myriad of studies, the identities of the mitochondrial pyruvate carrier (MPC) were only confirmed very recently. Identification of the MPC facilitated several other recent advances. These include the finding of MPC’s inhibition by the insulin-sensitizing drug family thiazolidinediones, how cells respond flexibly to a reduction in MPC functionality, as well as insights into how changes in MPC levels affect oncogenic potential of cancer cells. These new findings, discussed here in this brief review, have important implications in therapeutic approaches towards metabolic disorders and cancer.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant No.81902616 to F.W.)Science and Technology Support Project in the field of biomedicine of Shanghai Science and Technology Action Plan(Grant No.19441909200,F.W.)+6 种基金Clinical Research Project of Shanghai Municipal Commission of Health and Family Planning(Grant No.20184Y0130,F.W.)Precision Medicine Program of Second Military Medical University(Grant No.2017JZ35,F.W.)Youth Startup Program of the Second Military Medical University(Grant No.2016QN12,F.W.)Jiangsu Provincial Medical Youth Talent(Grant No.QNRC2016739,X.W.)Shanghai Sailing Program(Grant No.21YF1423300,H.X.)Natural Science Foundation of Shanghai(Grant No.21ZR1437800,H.X.)Cross-disciplinary Research Fund of Shanghai Ninth People’s Hospital,Shanghai Jiaotong University School of Medicine(Grant No.YG2021QN75,H.X.).
文摘Objective:This study aimed to evaluate the effects of mitochondrial pyruvate carrier(MPC)blockade on the sensitivity of detection and radiotherapy of prostate cancer(PCa).Methods:We investigated glycolysis reprogramming and MPC changes in patients with PCa by using metabolic profiling,RNASeq,and tissue microarrays.Transient blockade of pyruvate influx into mitochondria was observed in cellular studies to detect its different effects on prostate carcinoma cells and benign prostate cells.Xenograft mouse models were injected with an MPC inhibitor to evaluate the sensitivity of 18F-fluorodeoxyglucose positron emission tomography with computed tomography and radiotherapy of PCa.Furthermore,the molecular mechanism of this different effect of transient blockage towards benign prostate cells and prostate cancer cells was studied in vitro.Results:MPC was elevated in PCa tissue compared with benign prostate tissue,but decreased during cancer progression.The transient blockade increased PCa cell proliferation while decreasing benign prostate cell proliferation,thus increasing the sensitivity of PCa cells to 18F-PET/CT(SUVavg,P=0.016;SUVmax,P=0.03)and radiotherapy(P<0.01).This differential effect of MPC on PCa and benign prostate cells was dependent on regulation by a VDAC1-MPC-mitochondrial homeostasis-glycolysis pathway.Conclusions:Blockade of pyruvate influx into mitochondria increased glycolysis levels in PCa but not in non-carcinoma prostate tissue.This transient blockage sensitized PCa to both detection and radiotherapy,thus indicating that glycolytic potential is a novel mechanism underlying PCa progression.The change in the mitochondrial pyruvate influx caused by transient MPC blockade provides a critical target for PCa diagnosis and treatment.
文摘Abscisic acid （ABA） regulates ion channel activity and stomatal movements in response to drought and other stresses. Here, we show that the Arabidopsis thaliana gene NRGA1 is a putative mitochondrial pyruvate carrier which negatively regulates ABA-induced guard cell signaling. NRGA1 transcript was abundant in the A. thaliana leaf and par- ticularly in the guard cells, and its product was directed to the mitochondria. The heterologous co-expression of NRGA1 and AtMPC1 in yeast complemented a loss-of-function mitochondrial pyruvate carrier （MPC） mutant. The nrgal loss-of- function mutant was very sensitive to the presence of ABA in the context of stomatal movements, and exhibited a height- ened tolerance to drought stress. Disruption of NRGA1 gene resulted in increased ABA inhibition of inward K＋ currents and ABA activation of slow anion currents in guard cells. The nrgal/NRGA1 functional complementation lines restored the mutant＇s phenotypes. Furthermore, transgenic lines of constitutively overexpressing NRGA1 showed opposite stomatal responses, reduced drought tolerance, and ABA sensitivity of guard cell inward K＋ channel inhibition and anion channel activation. Our findings highlight a putative role for the mitochondrial pyruvate carrier in guard cell ABA signaling in response to drought.
