Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 7.840
Filtrar
1.
Ecotoxicol Environ Saf ; 208: 111752, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396077

RESUMO

Arsenic is a toxic heavy metal vastly dispersed all over the earth crust. It manifests several major adverse health issues to millions of arsenic exposed populations. Arsenic is associated with different types of cancer, cardiovascular disorders, diabetes, hypertension and many other diseases. On the contrary, arsenic (arsenic trioxide, As2O3) is used as a chemotherapeutic agent in the treatment of acute promyelocytic leukemia. Balance between arsenic induced cellular proliferations and apoptosis finally decide the outcome of its transformation rate. Arsenic propagates signals via cellular and nuclear pathways depending upon the chemical nature, and metabolic-fates of the arsenical compounds. Arsenic toxicity is propagated via ROS induced stress to DNA-repair mechanism and mitochondrial stability in the cell. ROS induced alteration in p53 regulation and some mitogen/ oncogenic functions determine the transformation outcome influencing cyclin-cdk complexes. Growth factor regulator proteins such as c-Jun, c-fos and c-myc are influenced by chronic arsenic exposure. In this review we have delineated arsenic induced ROS regulations of epidermal growth factor receptor (EGFR), NF-ĸß, MAP kinase, matrix-metalloproteinases (MMPs). The role of these signaling molecules has been discussed in relation to cellular apoptosis, cellular proliferation and neoplastic transformation. The arsenic stimulated pathways which help in proliferation and neoplastic transformation ultimately resulted in cancer manifestation whereas apoptotic pathways inhibited carcinogenesis. Therapeutic strategies against arsenic should be designed taking into account all these factors.


Assuntos
Arsênico/fisiologia , Proliferação de Células/fisiologia , Plásticos/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Arsênico/metabolismo , Trióxido de Arsênio/metabolismo , Trióxido de Arsênio/farmacologia , Arsenicais/metabolismo , Proliferação de Células/efeitos dos fármacos , Humanos , Mitocôndrias/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias , Óxidos/toxicidade , Transdução de Sinais/efeitos dos fármacos
2.
Life Sci ; 264: 118684, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33129877

RESUMO

AIMS: Fracture site is regionally hypoxic resulting from vasculature disruption. HIF-1αplays an essential role in fracture repair. This study aims to investigate the influence of FG4592 on the femur fracture of SD rats and the proliferation, migration of BMSCs. MATERIALS AND METHODS: After the femoral fracture model was established, computed tomography imaging and histological analyses were used to quantify bone healing and the expression of CD90, HIF-1α, VEGF were observed by means of immunohistochemistry method on Day 10 and Day 20. In addition, CCK-8 assay, transwell, flow cytometric analysis, laser confocal microscopy assay, western blot and rT-PCR were performed to text the proliferation and migration of BMSCs using FG4592. KEY FINDINGS: In vivo, FG4592 facilitated the repair of bone fracture by increasing the number of BMSCs and cartilage formation. In vitro, FG4592 markedly improved the proliferation, migration of BMSCs via upregulation of intracellular Ca2+, NO and concomitant decrease of ROS. Gene silencing of HIF-1α resulted in the opposite phenomenon in BMSCs with the treatment of FG4592. SIGNIFICANCE: The transplantation of BMSCs is the most promising candidate for the treatment of fracture non-union. We illustrated that FG4592 promoted the proliferation, migration of BMSCs via the HIF/Ca2+/NO/ROS pathway and further accelerated fracture healing. These results provide a deeper understanding for the mechanism of HIF in promoting fracture healing.


Assuntos
Fraturas do Colo Femoral/metabolismo , Glicina/análogos & derivados , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isoquinolinas/uso terapêutico , Transplante de Células-Tronco Mesenquimais/métodos , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Células da Medula Óssea/metabolismo , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Células Cultivadas , Fraturas do Colo Femoral/diagnóstico por imagem , Fraturas do Colo Femoral/terapia , Consolidação da Fratura/efeitos dos fármacos , Consolidação da Fratura/fisiologia , Glicina/farmacologia , Glicina/uso terapêutico , Isoquinolinas/farmacologia , Masculino , Células-Tronco Mesenquimais/metabolismo , Ratos , Ratos Sprague-Dawley
3.
Life Sci ; 264: 118691, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33166591

RESUMO

OBJECTIVE: To investigate the functional role of circSFMBT2 in vascular smooth muscle cell (VSMC) proliferation and migration and the underlying molecular mechanism. METHODS: The circSFMBT2 levels in neointimal tissue and platelet derived growth factor-BB (PDGF-BB)-treated VSMCs were detected by qRT-PCR. The role of circSFMBT2 in VSMC proliferation, migration and cell cycle distribution was assessed by MTT assay, transwell assay, wound healing assay and flow cytometry. The protein expression of contractile markers was evaluated by western blot. In vitro luciferase reporter assay, RNA pull-down assay, ChIP and coimmunoprecipitation (CoIP) were performed to explore the effects of circSFMBT2 on the downstream signaling pathway. RESULTS: We found that circSFMBT2 was markedly increased in neointimal tissue relative to normal tissue and PDGF-BB-treated VSMCs relative to control VSMCs. The knockdown of circSFMBT2 by siRNA significantly inhibited the proliferation and migration of VSMCs. Interestingly, circSFMBT2 knockdown enhanced the expression of contractile marker proteins including SM22α, SM myosin heavy chain (SMMHC) and calponin. Further data demonstrated that circSFMBT2 interacted with miR-331-3p as a competing endogenous RNA and up-regulated the expression of histone deacetylase 5 (HDAC5), thereby regulating the level of angiogenic factor with G patch and FHA domains (Aggf1). CONCLUSION: These results revealed that circSFMBT2 plays a vital role in VSMC proliferation and migration through the miR-331/HDAC5/Aggf1 axis, and suggest a novel target for treating proliferative vascular diseases.


Assuntos
Proliferação de Células/fisiologia , Histona Desacetilases/metabolismo , MicroRNAs/metabolismo , Músculo Liso Vascular/metabolismo , RNA Circular/metabolismo , Proteínas Repressoras/metabolismo , Humanos , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo
4.
Gene ; 766: 145153, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32950633

RESUMO

AIM: Acute lung injury (ALI) is the mild form of acute respiratory distress syndrome (ARDS) which is a common lung disease with a high incidence and mortality rate. Recent studies manifested that some circular RNAs were associated with ALI. In this study, we aimed to uncover the effect of circular RNA circ_0054633 on ALI initiation and progression and proposed a new mechanism related to ALI. METHODS: The lipopolysaccharides (LPS)-induced acute lung injury model were build both in vivo of rat and in vitro of primary murine pulmonary microvascular endothelial cells (MPVECs). Hematoxylin and eosin (H&E) was employed to observe the tissue morphology and estimate the degree of lung damage. We used real-time quantitative polymerase chain reaction (RT-qPCR) to measure the expression level of circ_0054633. The expression levels of inflammatory cytokines IL-17A and tumor necrosis factor-α (TNF-α) were detected by ELISA. The effects of circ_0054633 on MPVECs proliferation and apoptosis were detected with the help of CCK-8 and apoptosis assay, separately. The expression level of NF-κB p65 protein was measured by Western blot. RESULTS: circ_0054633, IL-17A, TNF-α and NF-κB p65 were all overexpressed in LPS-treated rat and MPVECs, and LPS enhanced the proliferation and apoptosis of MPVECs. While circ_0054633 silencing reversed the above promotion effects of LPS on IL-17A, TNF-α expression and MPVECs proliferation and apoptosis. CONCLUSIONS: Quietness of circ_0054633 alleviated LPS-induced ALI via NF-κB signaling pathway, implicating circ_0054633 may be a potential biomarker for diagnose and therapy of ALI.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Proliferação de Células/fisiologia , Células Endoteliais/metabolismo , Inflamação/metabolismo , NF-kappa B/metabolismo , RNA Circular/metabolismo , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Inflamação/induzido quimicamente , Interleucina-17/metabolismo , Lipopolissacarídeos/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
5.
Toxicology ; 447: 152631, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33188856

RESUMO

Cadmium (Cd) is recognized as a highly toxic heavy metal for humans in part because it is a multi-organ carcinogen. To clarify the mechanism of Cd carcinogenicity, we have established an experimental system using rat liver TRL1215 cells exposed to 2.5 µM Cd for 10 weeks and then cultured in Cd-free medium for an additional 4 weeks (total 14 weeks). Recently, we demonstrated, by using this experimental system, that 1) Cd stimulates cell invasion by suppression of apolipoprotein E (ApoE) expression, and 2) Cd induces DNA hypermethylation of the regulatory region of the ApoE gene. However, the underlying mechanism(s) as well as other potential genetic participants in the Cd-stimulated invasion are undefined. In the present work, we found that concurrent with enhanced invasion, Cd induced oxidative stress, coupled with the production of oxidative stress-sensitive metallothionein 2A (MT2A), which lead to down-modulation of ten-eleven translocation methylcytosine dioxygenase 1 (TET1: DNA demethylation) in addition to ApoE, without impacting DNA methyltransferases (DNMTs: DNA methylation) levels. Furthermore, the expression of tissue inhibitor of metalloproteinase 2 and 3 (TIMP2 and TIMP3) that are positively regulated by TET1, were decreased by Cd. The genes (ApoE/TET1/TIMP2/TIMP3) suppressed by Cd were further suppressed by hydroquinone (HQ; a reactive oxygen species [ROS] producer), whereas N-acetyl-l-cysteine (NAC; a ROS scavenger) prevented the suppression of their expression by HQ. In addition, NAC reversed their expression suppressed by Cd. Cd-stimulated cell invasion was clearly dampened by NAC in a concentration-dependent manner. Overall these findings suggest that 1) altered TET1 expression and activity together with ApoE are likely involved in the enhanced invasiveness due to Cd exposure, and 2) Cd down-regulation of TET1 likely evokes a reduction in ApoE expression (possible by DNA hypermethylation), and 3) anti-oxidants are effective in abrogation of the enhanced invasiveness that occurs concurrently with Cd-induced malignant transformation.


Assuntos
Cádmio/toxicidade , Dioxigenases/antagonistas & inibidores , Dioxigenases/biossíntese , Fígado/efeitos dos fármacos , Fígado/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Células Cultivadas , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/fisiologia , Relação Dose-Resposta a Droga , Fígado/patologia , Invasividade Neoplásica/patologia , Estresse Oxidativo/fisiologia , Ratos , Ratos Endogâmicos F344
6.
Toxicol Appl Pharmacol ; 410: 115336, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33212065

RESUMO

Non-small cell lung cancer (NSCLC) is one of the leading causes of cancer-related death worldwide. The abnormal activation of glycolytic metabolism and PTEN/AKT signaling in NSCLC cells are highly correlated with their proliferation abilities and viability. Ligustilide is one of the major bioactive components of multiple Chinese traditional medicine including Angelica sinensis and Ligusticum. Ligustilide exposure inhibits the proliferation and viability of multiple cancer cell lines in vitro. However, the impact of ligustilide to the progression of NSCLC and its detailed pharmacological mechanisms remain unclear. In this research, CCK-8 and colony formation assay were performed to demonstrate ligustilide treatment inhibited the viability and proliferation ability of NSCLC cells in vitro. Caspase-3/-7 activity assay and nucleosome ELISA assay were utilized to show ligustilide promoted the apoptosis of NSCLC cells. Metabolic analysis and qRT-PCR assay were used to demonstrated that ligustilide dampened aerobic glycolysis of NSCLC cells. Nude mice were exposed to 5 mg/kg ligustilide and ligustilide inhibited orthotopic NSCLC growth in vivo. qRT-PCR and Western blot analysis were performed to substantiate the regulatory function of ligustilide to PTEN/AKT signaling in NSCLC cells. Overall, this study revealed that ligustilide regulated the proliferation, apoptosis and aerobic glycolysis of NSCLC cells through PTEN/AKT signaling pathway.


Assuntos
4-Butirolactona/análogos & derivados , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proliferação de Células/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Neoplasias Pulmonares/metabolismo , 4-Butirolactona/farmacologia , 4-Butirolactona/uso terapêutico , Células A549 , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Proliferação de Células/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Glicólise/fisiologia , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Distribuição Aleatória
7.
Life Sci ; 265: 118861, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33301811

RESUMO

AIMS: LncRNAs are involved in many biological processes, and hypoxia contributed to the alterations of lncRNAs. Hypoxic preconditioned olfactory mucosa mesenchymal stem cells (OM-MSCs) exerted stronger anti-apoptotic ability in models of disease, but the molecules that controlled different biological characteristics of human OM-MSCs between hypoxic and normoxic conditions were unclear. The present study was aimed to explore the molecules that controlled different biological characteristics of human OM-MSCs between hypoxic and normoxic conditions. MAIN METHODS: LncRNAs and mRNAs expression profiles of human OM-MSCs between hypoxic (3%) and normoxic conditions were analyzed by Next-Generation Sequencing (NGS) analysis, bioinformatics analysis on these data were further performed. Moreover, loss-of function assay was conducted to investigate the impact of hypoxic condition on the proliferation and apoptosis of OM-MSCs. KEY FINDINGS: Through the comparative analysis and bioinformatics analysis, a total of 1741 lncRNAs and 1603 mRNAs were significant differentially expressed in the hypoxia group compared with normoxia group. Enrichment analysis revealed that differentially expressed genes of human OM-MSCs mainly participated in cell cycle regulation, secretin of cytokines and so on. Meanwhile, hypoxic condition significantly promoted proliferation and inhibited apoptosis of human OM-MSCs, following loss-of-function assays confirmed that lncRNA DARS-AS1 were involved in this regulatory process by hypoxic condition. Further prediction of targeted genes and the construction of lncRNA-miRNA-mRNA interaction network enriched the significance regarding the mechanism of DARS-AS1. SIGNIFICANCE: Altogether, these findings provided a new perspective for understanding the molecules expression patterns in hypoxia that contributed to corresponding phenotype alterations of OM-MSCs.


Assuntos
Proliferação de Células/fisiologia , Células-Tronco Mesenquimais/citologia , Mucosa Olfatória/citologia , RNA Longo não Codificante/genética , RNA Mensageiro/genética , Apoptose/fisiologia , Hipóxia Celular/fisiologia , Células Cultivadas , Regulação da Expressão Gênica , Humanos , MicroRNAs/genética
8.
Cancer Invest ; 39(1): 98-113, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33251876

RESUMO

Glioblastomas are the primary malignant tumors of brain tissues with poor prognosis and highly invasive phenotypes. Till now Ki-67 LI has emerged as a well-studied proliferation marker that aids in tumor grading, but labeling index alone cannot predict overall survival in gliomas. P21 activated kinase 1 (PAK1) - a serine/threonine kinase has been shown to function as downstream nodule for various oncogenic signaling pathways that promote neoplastic changes. This study is designed to evaluate the expression of PAK1 across various grades and its correlation with Ki-67 LI and overall survival rates among a total number of 140 clinical brain tumors of glioma patients. We also studied the activation status of phospho PAK1 in glioma tissues and established the role of PAK1 in proliferation of glioblatoma cell lines under γ-irradiation.This study provides molecular evidence signifying the role of PAK1 and its activation status in the progression of Gliomas to more aggressive phenotypes.


Assuntos
Neoplasias Encefálicas/enzimologia , Glioma/enzimologia , Quinases Ativadas por p21/metabolismo , Adulto , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Feminino , Glioma/genética , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Nat Commun ; 11(1): 6391, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33319779

RESUMO

Skin color patterns are ubiquitous in nature, impact social behavior, predator avoidance, and protection from ultraviolet irradiation. A leading model system for vertebrate skin patterning is the zebrafish; its alternating blue stripes and yellow interstripes depend on light-reflecting cells called iridophores. It was suggested that the zebrafish's color pattern arises from a single type of iridophore migrating differentially to stripes and interstripes. However, here we find that iridophores do not migrate between stripes and interstripes but instead differentiate and proliferate in-place, based on their micro-environment. RNA-sequencing analysis further reveals that stripe and interstripe iridophores have different transcriptomic states, while cryogenic-scanning-electron-microscopy and micro-X-ray diffraction identify different crystal-arrays architectures, indicating that stripe and interstripe iridophores are different cell types. Based on these results, we present an alternative model of skin patterning in zebrafish in which distinct iridophore crystallotypes containing specialized, physiologically responsive, organelles arise in stripe and interstripe by in-situ differentiation.


Assuntos
Diferenciação Celular/fisiologia , Cromatóforos/fisiologia , Cromatóforos/ultraestrutura , Pigmentação da Pele/fisiologia , Pele/ultraestrutura , Peixe-Zebra/metabolismo , Animais , Diferenciação Celular/genética , Proliferação de Células/fisiologia , Fator de Transcrição Associado à Microftalmia , Mutagênese , Pele/metabolismo , Pigmentação da Pele/genética , Transcriptoma , Difração de Raios X , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
10.
PLoS One ; 15(11): e0242337, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33180876

RESUMO

Visceral leishmaniasis (VL) is characterized by expansion of myeloid cells in the liver and spleen, which leads to a severe splenomegaly associated with higher risk of mortality. This increased cellularity is thought to be a consequence of recruitment of cells to the viscera. We studied whether the local proliferation of splenic myeloid cells contributes to increased splenic cellularity. We found that a monocyte-like population of adherent splenic cells from Leishmania donovani-infected hamsters had enhanced replicative capacity ex vivo and in vivo (BrdU incorporation, p<0.0001). In vitro assays demonstrated that proliferation was more pronounced in the proinflammatory M1 environment and that intracellular infection prevented proliferation. Secondary analysis of the published splenic transcriptome in the hamster model of progressive VL revealed a gene expression signature that included division of tumoral cells (Z = 2.0), cell cycle progression (Z = 2.3), hematopoiesis (Z = 2.8), proliferation of stem cells (Z = 2.5) and overexpression of proto-oncogenes. Regulators of myeloid cell proliferation were predicted in-silico (CSF2, TLR4, IFNG, IL-6, IL-4, RTK signaling, and STAT3). The in-silico prediction was confirmed with chemical inhibitors of PI3K/AKT, MAPK and STAT3 which decreased splenic myeloid cell division ex vivo. Hamsters infected with L. donovani treated with a STAT3 inhibitor had reduced in situ splenic myeloid proliferation (p = 0.03) and parasite burden. We conclude that monocyte-like myeloid cells have increased STAT3-dependent proliferation in the spleen of hamsters with visceral leishmaniasis and that inhibition of STAT3 reduces myeloid cell proliferation and parasite burden.


Assuntos
Leishmaniose Visceral/imunologia , Células Mieloides/metabolismo , Baço/metabolismo , Animais , Proliferação de Células/fisiologia , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Leishmania donovani/metabolismo , Leishmania donovani/patogenicidade , Leishmaniose Visceral/fisiopatologia , Fígado/imunologia , Fígado/metabolismo , Macrófagos/metabolismo , Mesocricetus , Células Mieloides/fisiologia , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Baço/imunologia , Transcriptoma
11.
Am J Pathol ; 190(12): 2464-2477, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33222991

RESUMO

Heat shock proteins (HSPs) are emerging as valuable potential molecular targets in breast cancer therapy owing to their diverse functions in cancer cells. This study investigated the potential role of heat shock protein 27 (HSP27, also known as HSPB1) in breast cancer through heat shock protein B8 (HSPB8). The correlation between HSP27 and HSPB8 was identified by using co-immunoprecipitation, immunoprecipitation, and SUMOylation assays. Through gain- and loss-of-function approaches in MCF-7 cells, the effect of HSP27 on HSPB8 expression, SUMOylation level, and protein stability of HSPB8, as well as on cell proliferation, migration, and stemness, was elucidated. A mouse xenograft model of breast cancer cells was established to verify the function of HSP27 in vivo. Results indicate that HSP27 and HSPB8 were highly expressed in breast cancer tissues and MCF-7 cells. HSP27 was also found to induce the SUMOylation of HSPB8 at the 106 locus and subsequently increased its protein stability, which resulted in accelerated proliferation, migration, and stemness of breast cancer cells in vitro along with increased tumor metastasis of breast cancer in vivo. However, these results could be reversed by the knockdown of HSPB8. Overall, HSP27 induces SUMOylation of HSPB8 to promote HSPB8 expression, thereby endorsing proliferation and metastasis of breast cancer cells. This study may provide insight for the development of new targets for breast cancer.


Assuntos
Neoplasias da Mama/patologia , Progressão da Doença , Proteínas de Choque Térmico HSP27/metabolismo , Metástase Neoplásica/patologia , Animais , Neoplasias da Mama/metabolismo , Proliferação de Células/fisiologia , Feminino , Proteínas de Choque Térmico/genética , Humanos , Camundongos , Proteínas Serina-Treonina Quinases/metabolismo , Sumoilação/fisiologia
12.
Arch Biochem Biophys ; 696: 108664, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33157102

RESUMO

BACKGROUND: Gastric cancer (GC) has a high rate of metastasis which thereason leading to death. Carnitine palmitoyl transferase 1a (CPT1A) has been reported to play a critical obstacle to various types of cancer progression, which is an attractive focus in anti-cancer therapy. However, the underlying molecular mechanisms of CPT1A involved in GC have not been clarified clear. METHODS: To determine the expression of CPT1A in human GC tissues and cells and illustrate whether it is correlated with the clinical pathologic characteristics and prognosis in GC patients. Its roles and potential mechanisms in regulating tumor growth and invasion were evaluated by CPT1A knockdown/overexpression of GC cells in vitro. RESULTS: Marked upregulation of CPT1A protein expression was observed in GC cells and tissues, which was associated with grade, pathological stage, lymph node metastasis and poor prognosis in patients with GC. CPT1A overexpression also promoted the proliferation, invasion, EMT process of GC cells. In addition, CPT1A upregulation activated GC cell fatty acid oxidation (FAO) via increasing NADP+/NADPH ratio, whereas inhibiting of FAO abolished the effects of CPT1A on GC cell proliferation and migration. CONCLUSION: Our results examine that CPT1A-mediated FAO activation increases GC cell proliferation and migration, supporting that CPT1A is a useful prognostic biomarker and an attractive focus for GC.


Assuntos
Carnitina O-Palmitoiltransferase/antagonistas & inibidores , Proliferação de Células/fisiologia , Ácidos Graxos/metabolismo , Neoplasias Gástricas/metabolismo , Carnitina O-Palmitoiltransferase/genética , Carnitina O-Palmitoiltransferase/metabolismo , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Ácidos Graxos/química , Regulação Neoplásica da Expressão Gênica/fisiologia , Técnicas de Silenciamento de Genes , Humanos , Oxirredução , Prognóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologia , Regulação para Cima
13.
Development ; 147(22)2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-33191273

RESUMO

Cell divisions and cell-fate decisions require stringent regulation for proper tissue development and homeostasis. The mammalian epidermis is a highly organized tissue structure that is sustained by epidermal stem cells (ESCs) that balance self-renewal and cell-fate decisions to establish a protective barrier, while replacing dying cells during homeostasis and in response to injury. Extensive work over past decades has provided insights into the regulatory mechanisms that control ESC specification, self-renewal and maintenance during different stages of the lifetime of an organism. In this Review, we discuss recent findings that have furthered our understanding of key regulatory features that allow ESCs to establish a functional barrier during development and to maintain tissue homeostasis in adults.


Assuntos
Células Epidérmicas/metabolismo , Epiderme/embriologia , Epiderme/crescimento & desenvolvimento , Homeostase/genética , Células-Tronco/metabolismo , Animais , Diferenciação Celular/fisiologia , Linhagem da Célula/fisiologia , Proliferação de Células/fisiologia , Autorrenovação Celular/fisiologia , Humanos , Transcrição Genética , Cicatrização/fisiologia
14.
Proc Natl Acad Sci U S A ; 117(46): 28828-28837, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33139571

RESUMO

Stem cells undergo differentiation in complex and dynamic environments wherein instructive signals fluctuate on various timescales. Thus, cells must be equipped to properly respond to the timing of signals, for example, to distinguish sustained signaling from transient noise. However, how stem cells respond to dynamic variations in differentiation cues is not well characterized. Here, we use optogenetic activation of ß-catenin signaling to probe the dynamic responses of differentiating adult neural stem cells (NSCs). We discover that, while elevated, sustained ß-catenin activation sequentially promotes proliferation and differentiation, transient ß-catenin induces apoptosis. Genetic perturbations revealed that the neurogenic/apoptotic fate switch was mediated through cell-cycle regulation by Growth Arrest and DNA Damage 45 gamma (Gadd45γ). Our results thus reveal a role for ß-catenin dynamics in NSC fate decisions and may suggest a role for signal timing to minimize cell-fate errors, analogous to kinetic proofreading of stem-cell differentiation.


Assuntos
Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , beta Catenina/metabolismo , Fator 3 Ativador da Transcrição/metabolismo , Animais , Apoptose/fisiologia , Encéfalo/citologia , Encéfalo/metabolismo , Pontos de Checagem do Ciclo Celular , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Células HEK293 , Hipocampo/citologia , Hipocampo/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neurogênese/fisiologia , Neurônios/citologia , Neurônios/metabolismo , Cultura Primária de Células , Ratos , Transdução de Sinais , Via de Sinalização Wnt
15.
Sci Rep ; 10(1): 20225, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33214606

RESUMO

Hepatocyte nuclear factor 1 homeobox alpha (HNF1α) is a transcription factor involved in endodermal organogenesis and pancreatic precursor cell differentiation and development. Earlier studies have reported a role for HNF1α in pancreatic ductal adenocarcinoma (PDAC) but it is controversial. The mechanism by which it impacts PDAC is yet to be explored in depth. In this study, using the online databases we observed that HNF1α is upregulated in PDAC, which was also confirmed by our immunohistochemical analysis of PDAC tissue microarray. Silencing HNF1α reduced the proliferative, migratory, invasive and colony forming capabilities of pancreatic cancer cells. Key markers involved in these processes (pPI3K, pAKT, pERK, Bcl2, Zeb, Snail, Slug) were significantly changed in response to alterations in HNF1α expression. On the other hand, overexpression of HNF1α did not induce any significant change in the aggressiveness of pancreatic cancer cells. Our results demonstrate that reduced expression of HNF1α leads to inhibition of pancreatic cancer growth and progression, which indicates that it could be a potential oncogene and target for PDAC.


Assuntos
Carcinoma Ductal Pancreático/metabolismo , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Regulação Neoplásica da Expressão Gênica , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Metástase Neoplásica/patologia , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Bases de Dados Factuais , Progressão da Doença , Humanos , Neoplasias Pancreáticas/patologia
16.
Sci Rep ; 10(1): 20189, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33214645

RESUMO

Sex differences are considered predictive factors in the development of several neurological diseases, which are also known to coincide with impaired phosphoinositide 3-kinase (PI3K)-AKT pathway activity, an essential signaling cascade involved in the control of several cellular functions such as autophagy and apoptosis. Here, under physiological conditions, we show important sex differences in the underlying balancing mechanisms that lead to similar AKT activity levels and autophagy and apoptosis processes in the two sexes. We demonstrate inverse sex-based expression of PTEN and Klotho, two important proteins that are known to negatively regulate the AKT pathway, and inverse sex-dependent levels of mTOR and FoxO3a activity. Taken together, our findings indicate that inverse sex-based regulation may be one of the underlying balancing mechanisms that differ between the sexes and a possible cause of sex-based autophagic and apoptotic responses to triggering situations that can lead to a sex-based predisposition to some neurological diseases.


Assuntos
Autofagia/fisiologia , Glucuronidase/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Transdução de Sinais/fisiologia , Animais , Apoptose/fisiologia , Proliferação de Células/fisiologia , Feminino , Glucuronidase/genética , Masculino , Camundongos , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores Sexuais
17.
Sci Rep ; 10(1): 17030, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046741

RESUMO

Succinylation is a novel post-translational modification identified on many proteins and is involved in multiple biological processes. Succinylation levels are dynamically regulated, balanced by succinylation and desuccinylation processes, and are closely connected to metabolic state in vivo. Sirtuins have been shown to possess NAD+-dependent desuccinylation activity in vitro and in vivo, among which the desuccinylation activity of SIRT5 is most extensively studied. Our understanding of the response of succinylation levels to different metabolic conditions, is hampered by the lack of a fast NAD+-dependent desuccinylation assay in a physiological context. In the present study, we therefore optimized and validated a fluorescence-based assay for measuring NAD+-dependent desuccinylation activity in cell lysates. Our results demonstrated that shorter and stricter reaction time was critical to approach the initial rate of NAD+-dependent desuccinylation activity in crude cell lysate systems, as compared to the desuccinylation reaction of purified His-SIRT5. Analysis of desuccinylation activity in SIRT5 knockout HEK293T cells confirmed the relevance of SIRT5 in cellular desuccinylation activity, as well as the presence of other NAD+-dependent desuccinylase activities. In addition, we were able to analyse desuccinylation and deacetylation activity in multiple cell lines using this assay. We showed a remarkably higher desuccinylase activity, but not deacetylase activity, in proliferative cultured muscle and adipose cells in comparison with their differentiated counterparts. Our results reveal an alteration in NAD+-dependent desuccinylation activity under different metabolic states.


Assuntos
Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Processamento de Proteína Pós-Traducional/fisiologia , Ácido Succínico/metabolismo , Células 3T3-L1 , Animais , Células HEK293 , Humanos , Camundongos , Sirtuínas/genética , Sirtuínas/metabolismo
18.
Sci Rep ; 10(1): 16368, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33004912

RESUMO

Hippocampal neurogenesis plays an important role in learning and memory function throughout life. Declines in this process have been observed in both aging and Alzheimer's disease (AD). Type 2 Diabetes mellitus (T2DM) is a disorder characterized by insulin resistance and impaired glucose metabolism. T2DM often results in cognitive decline in adults, and significantly increases the risk of AD development. The pathways underlying T2DM-induced cognitive deficits are not known. Some studies suggest that alterations in hippocampal neurogenesis may contribute to cognitive deterioration, however, the fate of neurogenesis in these studies is highly controversial. To address this problem, we utilized two models of T2DM: (1) obesity-independent MKR transgenic mice expressing a mutated form of the human insulin-like growth factor 1 receptor (IGF-1R) in skeletal muscle, and (2) Obesity-dependent db/db mice harboring a mutation in the leptin receptor. Our results show that both models of T2DM display compromised hippocampal neurogenesis. We show that the number of new neurons in the hippocampus of these mice is reduced. Clone formation capacity of neural progenitor cells isolated from the db/db mice is deficient. Expression of insulin receptor and epidermal growth factor receptor was reduced in hippocampal neurospheres isolated from db/db mice. Results from this study warrant further investigation into the mechanisms underlying decreased neurogenesis in T2DM and its link to the cognitive decline observed in this disorder.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Hipocampo/fisiopatologia , Neurogênese/fisiologia , Neurônios/fisiologia , Obesidade/fisiopatologia , Animais , Proliferação de Células/fisiologia , Disfunção Cognitiva/genética , Disfunção Cognitiva/fisiopatologia , Diabetes Mellitus Tipo 2/genética , Camundongos , Camundongos Transgênicos , Células-Tronco Neurais/fisiologia , Obesidade/genética , Receptor IGF Tipo 1/genética , Receptores para Leptina/genética
19.
Am J Physiol Cell Physiol ; 319(6): C1059-C1069, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33026833

RESUMO

CXC chemokine receptor 3 (CXCR3) A and its IFN-inducible ligands CXCL9 and CXCL10 regulate vascular remodeling and fibroblast motility. IL-13 is a profibrotic cytokine implicated in the pathogenesis of inflammatory and fibroproliferative conditions. Previous work from our laboratory has shown that CXCR3A is negatively regulated by IL-13 and is necessary for the basal regulation of the IL-13 receptor subunit IL-13Rα2. This study investigates the regulation of fibroblast phenotype, function, and downstream IL-13 signaling by CXCR3A in vitro. CXCR3A was overexpressed via transient transfection. CXCR3A-/- lung fibroblasts were isolated for functional analysis. Additionally, the contribution of CXCR3A to tissue remodeling following acute lung injury was assessed in vivo with wild-type (WT) and CXCR3-/- mice challenged with IL-13. CXCR3 and IL-13Rα2 displayed a reciprocal relationship after stimulation with either IL-13 or CXCR3 ligands. CXCR3A reduced expression of fibroblast activation makers, soluble collagen production, and proliferation. CXCR3A enhanced the basal expression of pERK1/2 while inducing IL-13-mediated downregulation of NF-κB-p65. CXCR3A-/- pulmonary fibroblasts were increasingly proliferative and displayed reduced contractility and α-smooth muscle actin expression. IL-13 challenge regulated expression of the CXCR3 ligands and soluble IL-13Rα2 levels in lungs and bronchoalveolar lavage fluid (BALF) of WT mice; this response was absent in CXCR3-/- mice. Alveolar macrophage accumulation and expression of genes involved in lung remodeling was increased in CXCR3-/- mice. We conclude that CXCR3A is a central antifibrotic factor in pulmonary fibroblasts, limiting fibroblast activation and reducing extracellular matrix (ECM) production. Therefore, targeting of CXCR3A may be a novel approach to regulating fibroblast activity in lung fibrosis and remodeling.


Assuntos
Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Subunidade alfa2 de Receptor de Interleucina-13/metabolismo , Fibrose Pulmonar/patologia , Receptores CXCR3/metabolismo , Células 3T3 , Animais , Linhagem Celular , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Feminino , Interleucina-13/genética , Interleucina-13/metabolismo , Subunidade alfa2 de Receptor de Interleucina-13/genética , Pulmão/citologia , Pulmão/metabolismo , Macrófagos Alveolares/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fator de Transcrição RelA/metabolismo
20.
Am J Physiol Cell Physiol ; 319(6): C1045-C1058, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33052069

RESUMO

Lymphangiogenesis, or formation of new lymphatic vessels, is a tightly regulated process that is controlled by growth factor signaling and biomechanical cues. Lymphatic endothelial cells (LECs) undergo remodeling, migration, and proliferation to invade the surrounding extracellular matrix (ECM) during both physiological and pathological lymphangiogenesis. This study optimized conditions for an in vitro three-dimensional (3-D) collagen-based model that induced LEC invasion and recapitulated physiological formation of lymphatic capillaries with lumens. Invasion of LECs was enhanced in the presence of sphingosine 1-phosphate (S1P). Effects of various known lymphangiogenic factors, vascular endothelial growth factor (VEGF)-A, basic fibroblast growth factor (bFGF), interleukin (IL)-8, and hepatocyte growth factor (HGF), were tested on LEC sprout formation synergistically with VEGF-C. Several of these growth factors significantly enhanced LEC invasion, and synergistic effects of some of these further enhanced the sprouting density and lumen volume. To determine the contribution of specific ECM components, we analyzed the expression of different integrin subunits. Basal expressions of the integrin α5- and integrin ß1-subunits were high in LECs. The addition of fibronectin, which mediates cellular responses through these integrins, enhanced LEC sprouting density and sprout length dose-dependently. siRNA-mediated knockdown of the integrin ß1-subunit suppressed LEC invasion and also inhibited VEGF receptor (VEGFR)3 and ERK activation. Furthermore, exposing LECs to the inflammatory mediator lipopolysaccharide (LPS) inhibited sprouting. This optimized model for LEC invasion includes S1P, VEGF-C, and fibronectin within a 3-D collagen matrix, along with VEGF-C, VEGF-A, bFGF, and HGF in the culture medium, and provides a useful tool to investigate the functional effect of various lymphangiogenic factors and inhibitors.


Assuntos
Células Endoteliais/metabolismo , Matriz Extracelular/metabolismo , Integrina beta1/metabolismo , Linfangiogênese/fisiologia , Vasos Linfáticos/citologia , Linhagem Celular , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fibronectinas/metabolismo , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Integrina beta1/genética , Interleucina-8/metabolismo , Lipopolissacarídeos , Lisofosfolipídeos/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator C de Crescimento do Endotélio Vascular/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA