目的研究线粒体转录因子A(TFAM)对宫颈癌HeLa细胞及骨肉瘤U2OS细胞的线粒体功能、自噬、增殖、侵袭、迁移的影响。方法HeLa、U2OS细胞转染TFAM小干扰片段(si-TFAM)下调TFAM表达,Mito-Tracker Red CMXRos染色结合激光共聚焦显微镜检测线...目的研究线粒体转录因子A(TFAM)对宫颈癌HeLa细胞及骨肉瘤U2OS细胞的线粒体功能、自噬、增殖、侵袭、迁移的影响。方法HeLa、U2OS细胞转染TFAM小干扰片段(si-TFAM)下调TFAM表达,Mito-Tracker Red CMXRos染色结合激光共聚焦显微镜检测线粒体膜电位(MMP)、MitoSOX^(TM)Red标记法检测线粒体活性氧(mtROS)水平、实时定量PCR检测线粒体DNA(mtDNA)的表达,免疫荧光细胞化学染色检测自噬体数量的变化。Western blot法检测TFAM、微管相关蛋白1轻链3A/B(LC3A/B)、自噬相关基因2A(ATG2A)、ATG2B、ATG9A、锌指转录因子Snail、基质金属蛋白酶2(MMP2)和MMP9的表达。CCK-8法、平板集落形成实验检测细胞增殖,Transwell^(TM)实验、划痕愈合实验检测细胞侵袭、迁移的变化。结果下调TFAM表达导致HeLa及U2OS细胞MMP减少,mtDNA拷贝数减少,mtROS产生量增加。LC3A/B蛋白含量较对照组明显下降,胞质内自噬体数量明显减少,自噬早期阶段蛋白ATG2B、ATG9A表达量明显减少。HeLa及U2OS细胞Snail、MMP2和MMP9蛋白表达均减少。干扰TFAM表达,抑制HeLa及U2OS细胞的增殖、侵袭、迁移能力。结论下调TFAM表达抑制线粒体功能,延缓自噬进程,降低宫颈癌细胞及骨肉瘤细胞的增殖、侵袭、迁移能力。展开更多
Activated G-protein-coupled receptor 39(GPR39)has been shown to attenuate inflammation by interacting with sirtuin 1(SIRT1)and peroxisome proliferator-activated receptor-γcoactivator 1α(PGC-1α).However,whether GPR3...Activated G-protein-coupled receptor 39(GPR39)has been shown to attenuate inflammation by interacting with sirtuin 1(SIRT1)and peroxisome proliferator-activated receptor-γcoactivator 1α(PGC-1α).However,whether GPR39 attenuates neuropathic pain remains unclear.In this study,we established a Sprague-Dawley rat model of spared nerve injury-induced neuropathic pain and found that GPR39 expression was significantly decreased in neurons and microglia in the spinal dorsal horn compared with sham-operated rats.Intrathecal injection of TC-G 1008,a specific agonist of GPR39,significantly alleviated mechanical allodynia in the rats with spared nerve injury,improved spinal cord mitochondrial biogenesis,and alleviated neuroinflammation.These changes were abolished by GPR39 small interfering RNA(siRNA),Ex-527(SIRT1 inhibitor),and PGC-1αsiRNA.Taken together,these findings show that GPR39 activation ameliorates mechanical allodynia by activating the SIRT1/PGC-1αpathway in rats with spared nerve injury.展开更多
Background:Mitochondria are key regulators in cell proliferation and apoptosis.Alterations in mitochondrial function are closely associated with inflammation and tumorigenesis.This study aimed to investigate whether m...Background:Mitochondria are key regulators in cell proliferation and apoptosis.Alterations in mitochondrial function are closely associated with inflammation and tumorigenesis.This study aimed to investigate whether mitochondrial transcription factor A(TFAM),a key regulator of mitochondrial DNA transcription and replication,is involved in the initiation and progression of colitis-associated cancer(CAC).Methods:TFAM expression was examined in tissue samples of inflammatory bowel diseases(IBD)and CAC by immunohistochemistry.Intestinal epithelial cell(IEC)-specific TFAM-knockout mice(TFAM^(△IEC))and colorectal cancer(CRC)cells with TFAM knockdown or overexpression were used to evaluate the role of TFAMin colitis and the initiation and progression ofCAC.The underlying mechanisms of TFAMwere also explored by analyzingmitochondrial respiration function and biogenesis.Results:The expression of TFAM was downregulated in active IBD and negatively associated with the disease activity.The downregulation of TFAM in IECs was induced by interleukin-6 in a signal transducer and activator of transcription 3(STAT3)/miR-23b-dependent manner.In addition,TFAM knockout impaired IECturnover to promote dextran sulfate sodium(DSS)-induced colitis inmice.Of note,TFAMknockout increased the susceptibility of mice to azoxymethane/DSSinduced CAC and TFAM overexpression protected mice from intestinal inflammation and colitis-associated tumorigenesis.By contrast,TFAM expression was upregulated in CAC tissues and contributed to cell growth.Furthermore,it was demonstrated that β-catenin induced the upregulation of TFAM through c-Myc in CRC cells.Mechanistically,TFAMpromoted the proliferation of both IECs and CRC cells by increasing mitochondrial biogenesis and activity.Conclusions:TFAM plays a dual role in the initiation and progression of CAC,providing a novel understanding of CAC pathogenesis.展开更多
文摘目的研究线粒体转录因子A(TFAM)对宫颈癌HeLa细胞及骨肉瘤U2OS细胞的线粒体功能、自噬、增殖、侵袭、迁移的影响。方法HeLa、U2OS细胞转染TFAM小干扰片段(si-TFAM)下调TFAM表达,Mito-Tracker Red CMXRos染色结合激光共聚焦显微镜检测线粒体膜电位(MMP)、MitoSOX^(TM)Red标记法检测线粒体活性氧(mtROS)水平、实时定量PCR检测线粒体DNA(mtDNA)的表达,免疫荧光细胞化学染色检测自噬体数量的变化。Western blot法检测TFAM、微管相关蛋白1轻链3A/B(LC3A/B)、自噬相关基因2A(ATG2A)、ATG2B、ATG9A、锌指转录因子Snail、基质金属蛋白酶2(MMP2)和MMP9的表达。CCK-8法、平板集落形成实验检测细胞增殖,Transwell^(TM)实验、划痕愈合实验检测细胞侵袭、迁移的变化。结果下调TFAM表达导致HeLa及U2OS细胞MMP减少,mtDNA拷贝数减少,mtROS产生量增加。LC3A/B蛋白含量较对照组明显下降,胞质内自噬体数量明显减少,自噬早期阶段蛋白ATG2B、ATG9A表达量明显减少。HeLa及U2OS细胞Snail、MMP2和MMP9蛋白表达均减少。干扰TFAM表达,抑制HeLa及U2OS细胞的增殖、侵袭、迁移能力。结论下调TFAM表达抑制线粒体功能,延缓自噬进程,降低宫颈癌细胞及骨肉瘤细胞的增殖、侵袭、迁移能力。
基金supported by the National Notural Science Foundation of China,Nos.82071556 and 82271291 (both to WM)
文摘Activated G-protein-coupled receptor 39(GPR39)has been shown to attenuate inflammation by interacting with sirtuin 1(SIRT1)and peroxisome proliferator-activated receptor-γcoactivator 1α(PGC-1α).However,whether GPR39 attenuates neuropathic pain remains unclear.In this study,we established a Sprague-Dawley rat model of spared nerve injury-induced neuropathic pain and found that GPR39 expression was significantly decreased in neurons and microglia in the spinal dorsal horn compared with sham-operated rats.Intrathecal injection of TC-G 1008,a specific agonist of GPR39,significantly alleviated mechanical allodynia in the rats with spared nerve injury,improved spinal cord mitochondrial biogenesis,and alleviated neuroinflammation.These changes were abolished by GPR39 small interfering RNA(siRNA),Ex-527(SIRT1 inhibitor),and PGC-1αsiRNA.Taken together,these findings show that GPR39 activation ameliorates mechanical allodynia by activating the SIRT1/PGC-1αpathway in rats with spared nerve injury.
基金National Natural Science Foundation of China,Grant/Award Numbers:82072722,81830070,81772935,81672340StateKey Laboratory ofCancer Biology Project,Grant/Award Number:CBSKL2019ZZ26。
文摘Background:Mitochondria are key regulators in cell proliferation and apoptosis.Alterations in mitochondrial function are closely associated with inflammation and tumorigenesis.This study aimed to investigate whether mitochondrial transcription factor A(TFAM),a key regulator of mitochondrial DNA transcription and replication,is involved in the initiation and progression of colitis-associated cancer(CAC).Methods:TFAM expression was examined in tissue samples of inflammatory bowel diseases(IBD)and CAC by immunohistochemistry.Intestinal epithelial cell(IEC)-specific TFAM-knockout mice(TFAM^(△IEC))and colorectal cancer(CRC)cells with TFAM knockdown or overexpression were used to evaluate the role of TFAMin colitis and the initiation and progression ofCAC.The underlying mechanisms of TFAMwere also explored by analyzingmitochondrial respiration function and biogenesis.Results:The expression of TFAM was downregulated in active IBD and negatively associated with the disease activity.The downregulation of TFAM in IECs was induced by interleukin-6 in a signal transducer and activator of transcription 3(STAT3)/miR-23b-dependent manner.In addition,TFAM knockout impaired IECturnover to promote dextran sulfate sodium(DSS)-induced colitis inmice.Of note,TFAMknockout increased the susceptibility of mice to azoxymethane/DSSinduced CAC and TFAM overexpression protected mice from intestinal inflammation and colitis-associated tumorigenesis.By contrast,TFAM expression was upregulated in CAC tissues and contributed to cell growth.Furthermore,it was demonstrated that β-catenin induced the upregulation of TFAM through c-Myc in CRC cells.Mechanistically,TFAMpromoted the proliferation of both IECs and CRC cells by increasing mitochondrial biogenesis and activity.Conclusions:TFAM plays a dual role in the initiation and progression of CAC,providing a novel understanding of CAC pathogenesis.
