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1.
PLoS Genet ; 17(12): e1009971, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34965247

RESUMO

Rothmund-Thomson syndrome (RTS) is an autosomal recessive genetic disorder characterized by poikiloderma, small stature, skeletal anomalies, sparse brows/lashes, cataracts, and predisposition to cancer. Type 2 RTS patients with biallelic RECQL4 pathogenic variants have multiple skeletal anomalies and a significantly increased incidence of osteosarcoma. Here, we generated RTS patient-derived induced pluripotent stem cells (iPSCs) to dissect the pathological signaling leading to RTS patient-associated osteosarcoma. RTS iPSC-derived osteoblasts showed defective osteogenic differentiation and gain of in vitro tumorigenic ability. Transcriptome analysis of RTS osteoblasts validated decreased bone morphogenesis while revealing aberrantly upregulated mitochondrial respiratory complex I gene expression. RTS osteoblast metabolic assays demonstrated elevated mitochondrial respiratory complex I function, increased oxidative phosphorylation (OXPHOS), and increased ATP production. Inhibition of mitochondrial respiratory complex I activity by IACS-010759 selectively suppressed cellular respiration and cell proliferation of RTS osteoblasts. Furthermore, systems analysis of IACS-010759-induced changes in RTS osteoblasts revealed that chemical inhibition of mitochondrial respiratory complex I impaired cell proliferation, induced senescence, and decreased MAPK signaling and cell cycle associated genes, but increased H19 and ribosomal protein genes. In summary, our study suggests that mitochondrial respiratory complex I is a potential therapeutic target for RTS-associated osteosarcoma and provides future insights for clinical treatment strategies.


Assuntos
Complexo I de Transporte de Elétrons/genética , Osteossarcoma/genética , RNA Longo não Codificante/genética , RecQ Helicases/genética , Síndrome de Rothmund-Thomson/genética , Trifosfato de Adenosina/biossíntese , Proliferação de Células/efeitos dos fármacos , Respiração Celular/efeitos dos fármacos , Senescência Celular/genética , Complexo I de Transporte de Elétrons/antagonistas & inibidores , Regulação da Expressão Gênica no Desenvolvimento/genética , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Mutação/genética , Osteoblastos/efeitos dos fármacos , Osteogênese/genética , Osteossarcoma/complicações , Osteossarcoma/patologia , Oxidiazóis/farmacologia , Fosforilação Oxidativa/efeitos dos fármacos , Piperidinas/farmacologia , Síndrome de Rothmund-Thomson/complicações , Síndrome de Rothmund-Thomson/patologia
2.
PLoS Comput Biol ; 18(2): e1009841, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35148308

RESUMO

While aerobic glycolysis, or the Warburg effect, has for a long time been considered a hallmark of tumor metabolism, recent studies have revealed a far more complex picture. Tumor cells exhibit widespread metabolic heterogeneity, not only in their presentation of the Warburg effect but also in the nutrients and the metabolic pathways they are dependent on. Moreover, tumor cells can switch between different metabolic phenotypes in response to environmental cues and therapeutic interventions. A framework to analyze the observed metabolic heterogeneity and plasticity is, however, lacking. Using a mechanistic model that includes the key metabolic pathways active in tumor cells, we show that the inhibition of phosphofructokinase by excess ATP in the cytoplasm can drive a preference for aerobic glycolysis in fast-proliferating tumor cells. The differing rates of ATP utilization by tumor cells can therefore drive heterogeneity with respect to the presentation of the Warburg effect. Building upon this idea, we couple the metabolic phenotype of tumor cells to their migratory phenotype, and show that our model predictions are in agreement with previous experiments. Next, we report that the reliance of proliferating cells on different anaplerotic pathways depends on the relative availability of glucose and glutamine, and can further drive metabolic heterogeneity. Finally, using treatment of melanoma cells with a BRAF inhibitor as an example, we show that our model can be used to predict the metabolic and gene expression changes in cancer cells in response to drug treatment. By making predictions that are far more generalizable and interpretable as compared to previous tumor metabolism modeling approaches, our framework identifies key principles that govern tumor cell metabolism, and the reported heterogeneity and plasticity. These principles could be key to targeting the metabolic vulnerabilities of cancer.


Assuntos
Glicólise , Neoplasias , Trifosfato de Adenosina/metabolismo , Ciclo do Ácido Cítrico , Humanos , Neoplasias/metabolismo , Fosfofrutoquinase-1/metabolismo
3.
Small ; 18(2): e2104944, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34802184

RESUMO

The charging process of secondary batteries is always associated with a large volume expansion of the alloying anodes, which in many cases, develops high compressive residual stresses near the propagating interface. This phenomenon causes a significant reduction in the rate performance of the anodes and is detrimental to the development of fast-charging batteries. However, for the Na-Sn battery system, the residual stresses that develop near the interface are not stored, but are relieved by the generation of high-density dislocations in crystalline Sn. Direct-contact diffusion experiments show that these dislocations facilitate the preferential transport of Na and accelerate the Na diffusion into crystalline Sn at ultrafast rates via "dislocation-pipe diffusion". Advanced analyses are performed to observe the evolution of atomic-scale structures while measuring the distribution and magnitude of residual stresses near the interface. In addition, multi-scale simulations that combined classical molecular dynamics and first-principles calculations are performed to explain the structural origins of the ultrafast diffusion rates observed in the Na-Sn system. These findings not only address the knowledge gaps regarding the relationship between pipe diffusion and the diffusivity of carrier ions but also provide guidelines for the appropriate selection of anode materials for use in fast-charging batteries.

4.
Proc Natl Acad Sci U S A ; 116(9): 3909-3918, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30733294

RESUMO

Metabolic plasticity enables cancer cells to switch their metabolism phenotypes between glycolysis and oxidative phosphorylation (OXPHOS) during tumorigenesis and metastasis. However, it is still largely unknown how cancer cells orchestrate gene regulation to balance their glycolysis and OXPHOS activities. Previously, by modeling the gene regulation of cancer metabolism we have reported that cancer cells can acquire a stable hybrid metabolic state in which both glycolysis and OXPHOS can be used. Here, to comprehensively characterize cancer metabolic activity, we establish a theoretical framework by coupling gene regulation with metabolic pathways. Our modeling results demonstrate a direct association between the activities of AMPK and HIF-1, master regulators of OXPHOS and glycolysis, respectively, with the activities of three major metabolic pathways: glucose oxidation, glycolysis, and fatty acid oxidation. Our model further characterizes the hybrid metabolic state and a metabolically inactive state where cells have low activity of both glycolysis and OXPHOS. We verify the model prediction using metabolomics and transcriptomics data from paired tumor and adjacent benign tissue samples from a cohort of breast cancer patients and RNA-sequencing data from The Cancer Genome Atlas. We further validate the model prediction by in vitro studies of aggressive triple-negative breast cancer (TNBC) cells. The experimental results confirm that TNBC cells can maintain a hybrid metabolic phenotype and targeting both glycolysis and OXPHOS is necessary to eliminate their metabolic plasticity. In summary, our work serves as a platform to symmetrically study how tuning gene activity modulates metabolic pathway activity, and vice versa.


Assuntos
Proteínas Quinases Ativadas por AMP/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Redes e Vias Metabólicas/genética , Neoplasias de Mama Triplo Negativas/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Linhagem Celular Tumoral , Ácidos Graxos/metabolismo , Feminino , Glucose/metabolismo , Glicólise/genética , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Mitocôndrias/metabolismo , Modelos Teóricos , Fosforilação Oxidativa , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
5.
Nano Lett ; 21(21): 9044-9051, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34714657

RESUMO

The fabrication of battery anodes simultaneously exhibiting large capacity, fast charging capability, and high cyclic stability is challenging because these properties are mutually contrasting in nature. Here, we report a rational strategy to design anodes outperforming the current anodes by simultaneous provision of the above characteristics without utilizing nanomaterials and surface modifications. This is achieved by promoting spontaneous structural evolution of coarse Sn particles to 3D-networked nanostructures during battery cycling in an appropriate electrolyte. The anode steadily exhibits large capacity (∼480 mAhg-1) and energy retention capability (99.9%) during >1500 cycles even at an ultrafast charging rate of 12 690 mAg-1 (15C). The structural and chemical origins of the measured properties are explained using multiscale simulations combining molecular dynamics and density functional theory calculations. The developed method is simple, scalable, and expandable to other systems and provides an alternative robust route to obtain nanostructured anode materials in large quantities.

6.
Br J Cancer ; 124(12): 1902-1911, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33859341

RESUMO

Cancer cells have the plasticity to adjust their metabolic phenotypes for survival and metastasis. A developmental programme known as epithelial-to-mesenchymal transition (EMT) plays a critical role during metastasis, promoting the loss of polarity and cell-cell adhesion and the acquisition of motile, stem-cell characteristics. Cells undergoing EMT or the reverse mesenchymal-to-epithelial transition (MET) are often associated with metabolic changes, as the change in phenotype often correlates with a different balance of proliferation versus energy-intensive migration. Extensive crosstalk occurs between metabolism and EMT, but how this crosstalk leads to coordinated physiological changes is still uncertain. The elusive connection between metabolism and EMT compromises the efficacy of metabolic therapies targeting metastasis. In this review, we aim to clarify the causation between metabolism and EMT on the basis of experimental studies, and propose integrated theoretical-experimental efforts to better understand the coupled decision-making of metabolism and EMT.


Assuntos
Metabolismo Energético/fisiologia , Transição Epitelial-Mesenquimal/fisiologia , Neoplasias/patologia , Animais , Diferenciação Celular , Transição Epitelial-Mesenquimal/genética , Humanos , Metástase Neoplásica , Neoplasias/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/fisiologia
7.
Haematologica ; 106(2): 495-512, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32029507

RESUMO

Ataxia telangiectasia mutated (ATM), a critical DNA damage sensor with protein kinase activity,is frequently altered in human cancers including mantle cell lymphoma (MCL). Loss of ATM protein is linked to accumulation of nonfunctional mitochondria and defective mitophagy, in both murine thymocytes and in A-T cells. However, the mechanistic role of ATM kinase in cancer cell mitophagy is unknown. Here, we provide evidence that FCCP-induced mitophagy in MCL and other cancer cell lines is dependent on ATM but independent of its kinase function. While Granta-519 MCL cells possess single copy and kinase dead ATM and are resistant to FCCP-induced mitophagy, both Jeko-1 and Mino cells are ATM proficient and induce mitophagy. Stable knockdown of ATM in Jeko-1 and Mino cells conferred resistance to mitophagy and was associated with reduced ATP production, oxygen consumption, and increased mROS. ATM interacts with the E3 ubiquitin ligase Parkin in a kinase-independent manner. Knockdown of ATM in HeLa cells resulted in proteasomal degradation of GFP-Parkin which was rescued by the proteasome inhibitor, MG132 suggesting that ATM-Parkin interaction is important for Parkin stability. Neither loss of ATM kinase activity in primary B cell lymphomas nor inhibition of ATM kinase in MCL, A-T and HeLa cell lines mitigated FCCP or CCCP-induced mitophagy suggesting that ATM kinase activity is dispensable for mitophagy. Malignant B-cell lymphomas without detectable ATM, Parkin, Pink1, and Parkin-Ub ser65 phosphorylation were resistant to mitophagy, providing the first molecular evidence of ATM's role in mitophagy in MCL and other B-cell lymphomas.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia , Ataxia Telangiectasia , Linfoma de Célula do Manto , Adulto , Animais , Células HeLa , Humanos , Linfoma de Célula do Manto/genética , Camundongos , Mitofagia/genética , Fosforilação , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
8.
Nano Lett ; 19(6): 3692-3698, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31084032

RESUMO

Because of its effectiveness in blocking electrons, the solid electrolyte interface (SEI) suppresses decomposition reactions of the electrolyte and contributes to the stability and reversibility of batteries. Despite the critical role of SEI in determining the properties of batteries, the electrical properties of SEI layers have never been measured directly. In this paper, we present the first experimental results of the electrical resistivity of a LiF-rich SEI layer measured using a direct-contact microelectrical device mounted in an electron microscope. Measurements show that the SEI layer exhibits high electrical resistivity (2.3 × 105 Ω·m), which is comparable with those of typical insulating materials. Furthermore, a combined technique of advanced analyses and first-principles calculations show that the SEI layer is mainly composed of amorphous LiF and a minute nanocrystalline Li2CO3 compound. The electronic origin responsible for the high resistivity of the SEI layer is elucidated by calculating the band structures of various Li xF compounds and interpreting their effects on the resistivity. This study explains why SEI can prevent the degradation of electrode materials and consumption of Li ions in the electrolyte and thus can be viewed as a stepping stone for developing highly stable and reversible batteries.

9.
Biochem J ; 474(22): 3719-3732, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28972070

RESUMO

Syndecans (SDCs) are transmembrane proteoglycans that are involved in cell adhesion and cell communication. Specifically, SDC2 plays a key role in tumorigenesis, metastasis, and angiogenesis. Previously, we found that rat SDC2 is shed by matrix metalloproteinase-7 (MMP-7) in colon cancer cells. Here, we analyzed the susceptibility of rat SDC2 to various MMPs. We found that the rat SDC2 ectodomain (ECD) fused to the C-terminal Fc region, which was expressed in mammalian cells, was cleaved more efficiently by MMP-14 than MMP-7. Likewise, when anchored on the surface of HeLa cells, rat SDC2 was cleaved more efficiently by the treatment of MMP-14 than MMP-7 and was shed more readily by membrane-anchored MMP-14 than soluble MMP-14. Furthermore, MMP-14 cleaved recombinant SDC2-ECD expressed in Escherichia coli into multiple fragments. Using N-terminal amino acid sequencing and the top-down proteomics approach, we determined that the major cleavage sites were S88↓L89, T98↓M99, T100↓L101, D132↓P133, and N148↓L149 for rat SDC2-ECD and S55↓G56, S65↓P66, P75↓K76, N92↓I93 D122↓P123, and S138↓L139 for human SDC2-ECD. Finally, the rat and human SDC2-ECD lost the ability to suppress vascular endothelial growth factor-induced formation of capillary-like tubes by human umbilical vein endothelial cells following cleavage by MMP-14, but its major cleavage-site mutant of rat SDC2-ECD did not. These results suggest that MMP-14 is a novel enzyme responsible for degrading SDC2 and impairing its physiological roles including angiogenesis.


Assuntos
Células Endoteliais da Veia Umbilical Humana/fisiologia , Metaloproteinase 14 da Matriz/metabolismo , Metaloproteinase 14 da Matriz/farmacologia , Sindecana-2/biossíntese , Fator A de Crescimento do Endotélio Vascular/farmacologia , Animais , Células COS , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Células HeLa , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Insetos , Ratos
10.
Cancer Res ; 84(2): 291-304, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-37906431

RESUMO

Approximately one-third of endocrine-treated women with estrogen receptor alpha-positive (ER+) breast cancers are at risk of recurrence due to intrinsic or acquired resistance. Thus, it is vital to understand the mechanisms underlying endocrine therapy resistance in ER+ breast cancer to improve patient treatment. Mitochondrial fatty acid ß-oxidation (FAO) has been shown to be a major metabolic pathway in triple-negative breast cancer (TNBC) that can activate Src signaling. Here, we found metabolic reprogramming that increases FAO in ER+ breast cancer as a mechanism of resistance to endocrine therapy. A metabolically relevant, integrated gene signature was derived from transcriptomic, metabolomic, and lipidomic analyses in TNBC cells following inhibition of the FAO rate-limiting enzyme carnitine palmitoyl transferase 1 (CPT1), and this TNBC-derived signature was significantly associated with endocrine resistance in patients with ER+ breast cancer. Molecular, genetic, and metabolomic experiments identified activation of AMPK-FAO-oxidative phosphorylation (OXPHOS) signaling in endocrine-resistant ER+ breast cancer. CPT1 knockdown or treatment with FAO inhibitors in vitro and in vivo significantly enhanced the response of ER+ breast cancer cells to endocrine therapy. Consistent with the previous findings in TNBC, endocrine therapy-induced FAO activated the Src pathway in ER+ breast cancer. Src inhibitors suppressed the growth of endocrine-resistant tumors, and the efficacy could be further enhanced by metabolic priming with CPT1 inhibition. Collectively, this study developed and applied a TNBC-derived signature to reveal that metabolic reprogramming to FAO activates the Src pathway to drive endocrine resistance in ER+ breast cancer. SIGNIFICANCE: Increased fatty acid oxidation induced by endocrine therapy activates Src signaling to promote endocrine resistance in breast cancer, which can be overcome using clinically approved therapies targeting FAO and Src.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Linhagem Celular Tumoral , Fosforilação , Transdução de Sinais , Ácidos Graxos/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética
11.
Cancer Lett ; 587: 216724, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38373689

RESUMO

CD24 is a well-characterized breast cancer (BC) stem cell (BCSC) marker. Primary breast tumor cells having CD24-negativity together with CD44-positivity is known to maintain high metastatic potential. However, the functional role of CD24 gene in triple-negative BC (TNBC), an aggressive subtype of BC, is not well understood. While the significance of CD24 in regulating immune pathways is well recognized in previous studies, the significance of CD24 low expression in onco-signaling and metabolic rewiring is largely unknown. Using CD24 knock-down and over-expression TNBC models, our in vitro and in vivo analysis suggest that CD24 is a tumor suppressor in metastatic TNBC. Comprehensive in silico gene expression analysis of breast tumors followed by lipidomic and metabolomic analyses of CD24-modulated cells revealed that CD24 negativity induces mitochondrial oxidative phosphorylation and reprograms TNBC metabolism toward the fatty acid beta-oxidation (FAO) pathway. CD24 silencing activates PPARα-mediated regulation of FAO in TNBC cells. Further analysis using reverse-phase protein array and its validation using CD24-modulated TNBC cells and xenograft models nominated CD24-NF-κB-CPT1A signaling pathway as the central regulatory mechanism of CD24-mediated FAO activity. Overall, our study proposes a novel role of CD24 in metabolic reprogramming that can open new avenues for the treatment strategies for patients with metastatic TNBC.


Assuntos
NF-kappa B , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/patologia , PPAR alfa/genética , Linhagem Celular Tumoral , Ácidos Graxos/metabolismo , Antígeno CD24/genética , Antígeno CD24/metabolismo
12.
iScience ; 27(6): 109995, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38868185

RESUMO

The canonical mechanism behind tamoxifen's therapeutic effect on estrogen receptor α/ESR1+ breast cancers is inhibition of ESR1-dependent estrogen signaling. Although ESR1+ tumors expressing wild-type p53 were reported to be more responsive to tamoxifen (Tam) therapy, p53 has not been factored into choice of this therapy and the mechanism underlying the role of p53 in Tam response remains unclear. In a window-of-opportunity trial on patients with newly diagnosed stage I-III ESR1+/HER2/wild-type p53 breast cancer who were randomized to arms with or without Tam prior to surgery, we reveal that the ESR1-p53 interaction in tumors was inhibited by Tam. This resulted in functional reactivation of p53 leading to transcriptional reprogramming that favors tumor-suppressive signaling, as well as downregulation of oncogenic pathways. These findings illustrating the convergence of ESR1 and p53 signaling during Tam therapy enrich mechanistic understanding of the impact of p53 on the response to Tam therapy.

13.
J Proteome Res ; 12(8): 3547-60, 2013 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-23815085

RESUMO

Tissue inhibitor of metalloproteinases-1 (TIMP-1) inhibits matrix metalloproteinases (MMPs) by binding at a 1:1 stoichiometry. Here we have shown the involvement of N-glycosylation in the MMP inhibitory ability of TIMP-1. TIMP-1, purified from HEK 293 cells overexpressing TIMP-1 (293 TIMP-1), showed less binding and inhibitory abilities to MMPs than TIMP-1 purified from fibroblasts or SF9 insect cells infected with TIMP-1 baculovirus. Following deglycosylation of TIMP-1, all forms of TIMP-1 showed similar levels of MMP binding and inhibition, suggesting that glycosylation is involved in the regulation of these TIMP-1 activities. Analysis of the N-glycan structures showed that SF9 TIMP-1 has the simplest N-glycan structures, followed by fibroblast TIMP-1 and 293 TIMP-1, in order of increasing complexity in their N-glycan structures. Further analyses showed that cleavage of outer arm fucose residues from the N-glycans of 293 TIMP-1 or knockdown of both FUT4 and FUT7 (which encode for fucosyltransferases that add outer arm fucose residues to N-glycans) enhanced the MMP-binding and catalytic abilities of 293 TIMP-1, bringing them up to the levels of the other TIMP-1. These results demonstrate that the ability of TIMP-1 to inhibit MMPs is at least in part regulated by outer arm fucosylation of its N-glycans.


Assuntos
Fucose/química , Metaloproteinase 1 da Matriz/química , Polissacarídeos/química , Inibidor Tecidual de Metaloproteinase-1/química , Animais , Baculoviridae/genética , Sítios de Ligação , Sequência de Carboidratos , Fibroblastos/citologia , Fibroblastos/metabolismo , Fucose/metabolismo , Fucosiltransferases/deficiência , Fucosiltransferases/genética , Regulação da Expressão Gênica , Células HEK293 , Humanos , Antígenos CD15/genética , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Polissacarídeos/metabolismo , Ligação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Células Sf9 , Transdução de Sinais , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Spodoptera , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo
14.
Nutr Cancer ; 65(8): 1192-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24099040

RESUMO

Matrix metalloproteinases (MMPs) play an important role in tissue remodeling during normal physiological situations and pathological implications such as tumor invasion and metastasis. MMP inhibitors were screened from extracts of medicinal herbs by an enzymatic assay using the MMP-14 catalytic domain. Among samples tested, a methanol extract of the root of Dalbergia odorifera T. CHEN (Leguminosae) showed the strongest inhibitory activity. The inhibitory component was purified through fractionation methods and identified as fisetin, abundant in many fruits and vegetables. In addition to inhibition of MMP-14, fisetin inhibits MMP-1, MMP-3, MMP-7, and MMP-9, more efficiently than a naturally occurring MMP inhibitor tetracycline. Fisetin dose-dependently inhibits proliferation of fibrosarcoma HT-1080 cells and human umbilical vascular endothelial cells (HUVECs), MMP-14-mediated activation of proMMP-2 in HT-1080 cells, invasiveness of HT-1080 cells, and in vitro tube formation of HUVECs. Therefore, fisetin could be valuable as a chemopreventive agent against cancer and a lead compound for development of therapeutic MMP inhibitors.


Assuntos
Flavonoides/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Inibidores de Metaloproteinases de Matriz/farmacologia , Metaloproteinases da Matriz/metabolismo , Extratos Vegetais/farmacologia , Apolipoproteínas E/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quimioprevenção , Dalbergia/química , Relação Dose-Resposta a Droga , Precursores Enzimáticos/genética , Precursores Enzimáticos/metabolismo , Flavonóis , Gelatinases/genética , Gelatinases/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Invasividade Neoplásica , Raízes de Plantas/química
15.
Health Informatics J ; 29(1): 14604582231169297, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36995242

RESUMO

Objectives: This study aimed to evaluate the quality and readability of web pages providing information about hand osteoarthritis using several authorized methods.Methods: A web page exploration was performed using the Google internet search engine. The three search terms, "hand osteoarthritis," "finger osteoarthritis," and "hand OA," were used and the top 100 ranked websites were selected and divided into six categories. The Health on the Net Foundation (HON) grade scale, an instrument for judging the quality of written consumer health information on treatment choice (DISCERN instrument), and the Ensuring Quality Information for Patients (EQIP) score were used to evaluate the quality of each website. The Flesch-Kincaid reading ease (FRE) score, Flesch-Kincaid grade (FKG) level, Gunning-Fog index, and Simple Measure of Gobbledygook grade level were used to evaluate website readability.Results: Among 300 websites, 57 websites were selected following exclusion criteria. News portal websites, including the online version of newspapers and periodicals, showed the highest score in all three quality evaluation tools. Only four websites were regarded as high-quality websites based on the HON grade scale (n = 3) and the EQIP score (n = 1). Each type of website showed an average FKG level higher than 7th grade and obtained an average FRE score of less than 80 points, indicating an inappropriate level for a layperson to read.Conclusions: The online information about hand osteoarthritis is low quality and difficult to read for the general public. There is a need to enhance the quality and readability of web-based information related to hand osteoarthritis for patients to obtain credible information and receive proper treatment for the disease.


Assuntos
Compreensão , Informação de Saúde ao Consumidor , Humanos , Leitura , Ferramenta de Busca , Internet
16.
Orthop J Sports Med ; 11(3): 23259671221143996, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36970316

RESUMO

Background: The remnant preservation of a primary vertical graft in revision anterior cruciate ligament reconstruction (ACLR) can benefit anteroposterior stability. However, studies that address this concept are rare. Purpose: To evaluate clinical outcomes of remnant preservation of primary vertical graft in revision ACLR. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 74 patients with revision ACLR were included in this retrospective study. Remnant preservation revision ACLR was performed only in patients with primary vertical grafts. The patients were divided into 2 groups according to whether the primary remnant vertical graft was preserved (remnant group; n = 48) or absent or sacrificed (no-remnant group; n = 26). The remnant group was further divided according to the degree of remnant tissue: sufficiently preserved subgroup (graft coverage, ≥50%; n = 25) and insufficiently preserved subgroup (graft coverage, <50%; n = 23). Clinical outcomes were evaluated using the International Knee Documentation Committee (IKDC) subjective form, Lysholm score, Tegner activity scale, manual laxity tests, and side-to-side difference in anterior tibial translation on Telos stress radiographs. Results: The mean time to final follow-up was 40.7 ± 16.8 months. The remnant group showed more improved results in the postoperative Lachman test and Telos side-to-side difference than did the no-remnant group (P = .017 and .016, respectively). The post hoc test revealed that the side-to-side difference in laxity in the sufficiently preserved subgroup significantly outperformed that in the no-remnant group (P = .001), although no significant difference existed between the insufficiently preserved and no-remnant subgroups (P = .850). The postoperative IKDC subjective form, Lysholm score, and Tegner activity scale did not show significant differences between the 2 groups (P = .480, .277, and .883, respectively). Conclusion: The remnant preservation of the primary vertical graft in revision ACLR may result in better anteroposterior stability. However, subjective outcomes in the remnant group did not exceed that of the no-remnant group. The subgroup analysis revealed that only sufficiently preserved remnants demonstrated better anteroposterior stability.

17.
Nat Metab ; 5(9): 1595-1614, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37653044

RESUMO

In most eukaryotic cells, fatty acid synthesis (FAS) occurs in the cytoplasm and in mitochondria. However, the relative contribution of mitochondrial FAS (mtFAS) to the cellular lipidome is not well defined. Here we show that loss of function of Drosophila mitochondrial enoyl coenzyme A reductase (Mecr), which is the enzyme required for the last step of mtFAS, causes lethality, while neuronal loss of Mecr leads to progressive neurodegeneration. We observe a defect in Fe-S cluster biogenesis and increased iron levels in flies lacking mecr, leading to elevated ceramide levels. Reducing the levels of either iron or ceramide suppresses the neurodegenerative phenotypes, indicating an interplay between ceramide and iron metabolism. Mutations in human MECR cause pediatric-onset neurodegeneration, and we show that human-derived fibroblasts display similar elevated ceramide levels and impaired iron homeostasis. In summary, this study identifies a role of mecr/MECR in ceramide and iron metabolism, providing a mechanistic link between mtFAS and neurodegeneration.


Assuntos
Adipogenia , Mitocôndrias , Criança , Animais , Humanos , Ceramidas , Drosophila , Ferro , Ácidos Graxos
18.
Elife ; 122023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37417957

RESUMO

Flavin adenine dinucleotide (FAD) interacts with flavoproteins to mediate oxidation-reduction reactions required for cellular energy demands. Not surprisingly, mutations that alter FAD binding to flavoproteins cause rare inborn errors of metabolism (IEMs) that disrupt liver function and render fasting intolerance, hepatic steatosis, and lipodystrophy. In our study, depleting FAD pools in mice with a vitamin B2-deficient diet (B2D) caused phenotypes associated with organic acidemias and other IEMs, including reduced body weight, hypoglycemia, and fatty liver disease. Integrated discovery approaches revealed B2D tempered fasting activation of target genes for the nuclear receptor PPARα, including those required for gluconeogenesis. We also found PPARα knockdown in the liver recapitulated B2D effects on glucose excursion and fatty liver disease in mice. Finally, treatment with the PPARα agonist fenofibrate activated the integrated stress response and refilled amino acid substrates to rescue fasting glucose availability and overcome B2D phenotypes. These findings identify metabolic responses to FAD availability and nominate strategies for the management of organic acidemias and other rare IEMs.


Assuntos
Glucose , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Glucose/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Flavina-Adenina Dinucleotídeo/metabolismo , Ácidos Graxos/metabolismo , Fígado/metabolismo , Jejum/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Oxirredução , Flavoproteínas/metabolismo
19.
Biochem Biophys Res Commun ; 417(4): 1260-4, 2012 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-22227189

RESUMO

The cell surface heparan sulfate proteoglycan syndecan-2 regulates the activation of matrix metalloproteinase-7 (MMP-7) as a docking receptor. Here, we demonstrate the role of MMP-7 on syndecan-2 shedding in colon cancer cells. Western blot analysis showed that shed syndecan-2 was found in the culture media from various colon cancer cells. Overexpression of MMP-7 enhanced syndecan-2 shedding, whereas the opposite was true when MMP-7 levels were knocked-down using small inhibitory RNAs. Consistently, HT29 cells treated with MMP-7, but neither MMP-2 nor MMP-9, showed increased shed syndecan-2 in a time- and concentration-dependent manner. Furthermore, MALDI-TOF MS analysis and N-terminal amino acid sequencing revealed that MMP-7 cleaved both recombinant syndecan-2 and an endogenously glycosylated syndecan-2 ectodomain in the N-terminus at Leu(149) residue in vitro. Taken together, the data suggest that MMP-7 directly mediates shedding of syndecan-2 from colon cancer cells.


Assuntos
Neoplasias do Colo/metabolismo , Metaloproteinase 7 da Matriz/metabolismo , Sindecana-2/metabolismo , Humanos , Metaloproteinase 7 da Matriz/genética , Estrutura Terciária de Proteína , Fatores de Transcrição , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases
20.
Uisahak ; 21(3): 477-512, 2012 Dec.
Artigo em Coreano | MEDLINE | ID: mdl-23388490

RESUMO

Hong Seok-hoo, who took charge of Jejungwon, was successful in translating Jiro Tsuboi's book titled "New Edition of Physiology Textbook (1897)" in Japanese and publishing it with a title of "New Edition of Physiology Textbook" in 1906. Jiro Tsuboi, the original author of that book, was a doctor having majored in Hygienics in Germany and was also known to have done pioneering work in Hygienics and Occupational and Environmental Medicine in Japan. At that time, he wrote that book for the purpose of teaching his students at Ordinary Middle School and Normal School. Therefore, it was not intended as a Physiology textbook for medical students, but an introductory book explaining Physiology with a wide range of subjects including hygienic matters in a broader sense. Hong Seok-hoo made an almost complete translation of the "New Edition of Physiology Textbook." While editing the book, however, he changed some of the most Japanese-style contents to meet the Korean conditions then, and made up for some insufficient contents with reference to the original author's other books. Although it was not included in an original version of that book, he also compiled a physiology dictionary in order to help Korean readers acquire medical terms in a more systematic way. Just like other textbooks of Jejungwon, the "New Edition of Physiology Textbook" was also put into Korean only. Hong Seok-hoo accepted Japanese-style medical terms, but also changed some of them or coined new words, considering the Korean circumstances then. He seemed to do so in an effort to introduce Western medicine in a more independent way while overcoming his limitations of translation. In particular, this book criticized that a long-term use of cosmetics might cause a serious lead poisoning from a Christian viewpoint, saying that a God-created human body should be kept intact as it is. In addition, in the course of reediting premodern books, the term "Lord" was changed into "God," which is considered a kind of fusion between traditional values and missionary medicine. While translating books, Jejungwon could put such fusion into practice because it was a hospital established under the banner of the propagation of Christianity. Besides the "New Edition of Physiology Textbook," at least five physiology textbooks were also translated into Korean in the last years of Daehan Empire for the purpose of teaching students modern subjects like Physiology, Health and Hygienics in educational institutions including Boseong School, Hwimun School and Soongsil School. On the other hand, the "New Edition of Physiology Textbook" was first translated at the end of Daehan Empire in order to foster more professional doctors in medical schools compared to those schools. In this respect, by translating the "New Edition of Physiology Textbook," Jejungwon can be considered as playing a pioneering role in translating Physiology textbooks in the late Daehan Empire.

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