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1.
Nat Commun ; 11(1): 4465, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901012

RESUMO

Titanium implants have been widely used in bone tissue engineering for decades. However, orthopedic implant-associated infections increase the risk of implant failure and even lead to amputation in severe cases. Although TiO2 has photocatalytic activity to produce reactive oxygen species (ROS), the recombination of generated electrons and holes limits its antibacterial ability. Here, we describe a graphdiyne (GDY) composite TiO2 nanofiber that combats implant infections through enhanced photocatalysis and prolonged antibacterial ability. In addition, GDY-modified TiO2 nanofibers exert superior biocompatibility and osteoinductive abilities for cell adhesion and differentiation, thus contributing to the bone tissue regeneration process in drug-resistant bacteria-induced implant infection.


Assuntos
Antibacterianos/química , Grafite , Nanofibras/química , Próteses e Implantes , Infecções Relacionadas à Prótese/prevenção & controle , Titânio , Células 3T3 , Animais , Materiais Biocompatíveis/química , Regeneração Óssea , Sobrevivência Celular , Modelos Animais de Doenças , Feminino , Teste de Materiais , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Nanocompostos/química , Osteogênese , Processos Fotoquímicos , Infecções Estafilocócicas/prevenção & controle
2.
mBio ; 11(5)2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32934084

RESUMO

Bats are primary reservoirs for multiple lethal human viruses, such as Ebola, Nipah, Hendra, rabies, severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome-related coronavirus (MERS-CoV), and, most recently, SARS-CoV-2. The innate immune systems of these immensely abundant, anciently diverged mammals remain insufficiently characterized. While bat genomes contain many endogenous retroviral elements indicative of past exogenous infections, little is known about restrictions to extant retroviruses. Here, we describe a major postentry restriction in cells of the yinpterochiropteran bat Pteropus alecto Primate lentiviruses (HIV-1, SIVmac) were potently blocked at early life cycle steps, with up to 1,000-fold decreases in infectivity. The block was specific, because nonprimate lentiviruses such as equine infectious anemia virus and feline immunodeficiency virus were unimpaired, as were foamy retroviruses. Interspecies heterokaryons demonstrated a dominant block consistent with restriction of incoming viruses. Several features suggested potential TRIM5 (tripartite motif 5) or myxovirus resistance protein 2 (MX2) protein restriction, including postentry action, cyclosporine sensitivity, and reversal by capsid cyclophilin A (CypA) binding loop mutations. Viral nuclear import was significantly reduced, and this deficit was substantially rescued by cyclosporine treatment. However, saturation with HIV-1 virus-like particles did not relieve the restriction at all. P. alecto TRIM5 was inactive against HIV-1 although it blocked the gammaretrovirus N-tropic murine leukemia virus. Despite major divergence in a critical N-terminal motif required for human MX2 activity, P. alecto MX2 had anti-HIV activity. However, this did not quantitatively account for the restriction and was independent of and synergistic with an additional CypA-dependent restriction. These results reveal a novel, specific restriction to primate lentiviruses in the Pteropodidae and advance understanding of bat innate immunity.IMPORTANCE The COVID-19 pandemic suggests that bat innate immune systems are insufficiently characterized relative to the medical importance of these animals. Retroviruses, e.g., HIV-1, can be severe pathogens when they cross species barriers, and bat restrictions corresponding to retroviruses are comparatively unstudied. Here, we compared the abilities of retroviruses from three genera (Lentivirus, Gammaretrovirus, and Spumavirus) to infect cells of the large fruit-eating bat P. alecto and other mammals. We identified a major, specific postentry restriction to primate lentiviruses. HIV-1 and SIVmac are potently blocked at early life cycle steps, but nonprimate lentiviruses and foamy retroviruses are entirely unrestricted. Despite acting postentry and in a CypA-dependent manner with features reminiscent of antiretroviral factors from other mammals, this restriction was not saturable with virus-like particles and was independent of P. alecto TRIM5, TRIM21, TRIM22, TRIM34, and MX2. These results identify a novel restriction and highlight cyclophilin-capsid interactions as ancient species-specific determinants of retroviral infection.


Assuntos
Quirópteros/imunologia , Gammaretrovirus/imunologia , Imunidade Inata/imunologia , Lentivirus de Primatas/imunologia , Spumavirus/imunologia , Células 3T3 , Animais , Aotidae , Gatos , Linhagem Celular , Quirópteros/virologia , Ciclofilina A/metabolismo , Furões , Gammaretrovirus/crescimento & desenvolvimento , Células HEK293 , Humanos , Lentivirus de Primatas/crescimento & desenvolvimento , Camundongos , Interferência de RNA , RNA Interferente Pequeno/genética , Spumavirus/crescimento & desenvolvimento , Proteínas com Motivo Tripartido/metabolismo
3.
Nat Commun ; 11(1): 4111, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807776

RESUMO

Mutational inactivation of VHL is the earliest genetic event in the majority of clear cell renal cell carcinomas (ccRCC), leading to accumulation of the HIF-1α and HIF-2α transcription factors. While correlative studies of human ccRCC and functional studies using human ccRCC cell lines have implicated HIF-1α as an inhibitor and HIF-2α as a promoter of aggressive tumour behaviours, their roles in tumour onset have not been functionally addressed. Herein we show using an autochthonous ccRCC model that Hif1a is essential for tumour formation whereas Hif2a deletion has only minor effects on tumour initiation and growth. Both HIF-1α and HIF-2α are required for the clear cell phenotype. Transcriptomic and proteomic analyses reveal that HIF-1α regulates glycolysis while HIF-2α regulates genes associated with lipoprotein metabolism, ribosome biogenesis and E2F and MYC transcriptional activities. HIF-2α-deficient tumours are characterised by increased antigen presentation, interferon signalling and CD8+ T cell infiltration and activation. Single copy loss of HIF1A or high levels of HIF2A mRNA expression correlate with altered immune microenvironments in human ccRCC. These studies reveal an oncogenic role of HIF-1α in ccRCC initiation and suggest that alterations in the balance of HIF-1α and HIF-2α activities can affect different aspects of ccRCC biology and disease aggressiveness.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Células 3T3 , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Western Blotting , Linfócitos T CD8-Positivos/metabolismo , Carcinoma de Células Renais/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Proliferação de Células/fisiologia , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Imuno-Histoquímica , Inflamação/genética , Inflamação/metabolismo , Neoplasias Renais/genética , Espectrometria de Massas , Camundongos , Proteômica/métodos , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA , Microambiente Tumoral/genética , Microambiente Tumoral/fisiologia
4.
PLoS Genet ; 16(8): e1008691, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32764743

RESUMO

Primary ciliary dyskinesia (PCD) is characterized by chronic airway disease, reduced fertility, and randomization of the left/right body axis. It is caused by defects of motile cilia and sperm flagella. We screened a cohort of affected individuals that lack an obvious axonemal defect for pathogenic variants using whole exome capture, next generation sequencing, and bioinformatic analysis assuming an autosomal recessive trait. We identified one subject with an apparently homozygous nonsense variant [(c.1762C>T), p.(Arg588*)] in the uncharacterized CFAP57 gene. Interestingly, the variant results in the skipping of exon 11 (58 amino acids), which may be due to disruption of an exonic splicing enhancer. In normal human nasal epithelial cells, CFAP57 localizes throughout the ciliary axoneme. Nasal cells from the PCD patient express a shorter, mutant version of CFAP57 and the protein is not incorporated into the axoneme. The missing 58 amino acids include portions of WD repeats that may be important for loading onto the intraflagellar transport (IFT) complexes for transport or docking onto the axoneme. A reduced beat frequency and an alteration in ciliary waveform was observed. Knockdown of CFAP57 in human tracheobronchial epithelial cells (hTECs) recapitulates these findings. Phylogenetic analysis showed that CFAP57 is highly conserved in organisms that assemble motile cilia. CFAP57 is allelic with the BOP2/IDA8/FAP57 gene identified previously in Chlamydomonas reinhardtii. Two independent, insertional fap57 Chlamydomonas mutant strains show reduced swimming velocity and altered waveforms. Tandem mass tag (TMT) mass spectroscopy shows that FAP57 is missing, and the "g" inner dyneins (DHC7 and DHC3) and the "d" inner dynein (DHC2) are reduced, but the FAP57 paralog FBB7 is increased. Together, our data identify a homozygous variant in CFAP57 that causes PCD that is likely due to a defect in the inner dynein arm assembly process.


Assuntos
Axonema/metabolismo , Transtornos da Motilidade Ciliar/genética , Códon sem Sentido , Dineínas/metabolismo , Proteínas/genética , Células 3T3 , Adulto , Animais , Axonema/fisiologia , Células Cultivadas , Chlamydomonas reinhardtii , Cílios/metabolismo , Cílios/fisiologia , Transtornos da Motilidade Ciliar/patologia , Sequência Conservada , Humanos , Masculino , Camundongos , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas/química , Proteínas/metabolismo , Mucosa Respiratória/metabolismo
5.
PLoS One ; 15(8): e0237095, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756599

RESUMO

Regular exercise is an effective strategy that is used to prevent and treat obesity as well as type 2 diabetes. Exercise-induced myokine secretion is considered a mechanism that coordinates communication between muscles and other organs. In order to examine the possibility of novel communications from muscle to adipose tissue mediated by myokines, we treated 3T3-L1 adipocytes with C2C12 myotube electrical pulse stimulation-conditioned media (EPS-CM), using a C2C12 myotube contraction system stimulated by an electrical pulse. Continuous treatment with myotube EPS-CM promoted adipogenesis of 3T3-L1 pre-adipocytes via the upregulation of the peroxisome proliferator-activated receptor-gamma (PPARγ) 2 and PPARγ-regulated gene expression. Furthermore, our results revealed that myotube EPS-CM induces lipolysis and secretion of adiponectin in mature adipocytes. EPS-CM obtained from a C2C12 myoblast culture did not induce such changes in these genes, suggesting that contraction-induced myokine(s) secretion occurs particularly in differentiated myotubes. Thus, contraction-induced secretion of myokine(s) promotes adipogenesis and lipid metabolism in 3T3-L1 adipocytes. These findings suggest the possibility that skeletal muscle communicates to adipose tissues during exercise, probably by the intermediary of unidentified myokines.


Assuntos
Adipócitos/citologia , Diferenciação Celular , Lipólise , Fibras Musculares Esqueléticas/metabolismo , Células 3T3 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adipogenia , Adiponectina/metabolismo , Animais , Comunicação Celular , Meios de Cultivo Condicionados/farmacologia , Camundongos , PPAR gama/metabolismo
6.
Int J Nanomedicine ; 15: 4275-4288, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606677

RESUMO

Purpose: Selenium nanoparticles (Se NPs) are promising antibacterial agents to tackle the growing problem of antimicrobial resistance. The aim of this study was to fabricate Se NPs with a net positive charge to enhance their antibacterial efficacy. Methods: Se NPs were coated with a positively charged protein - recombinant spider silk protein eADF4(κ16) - to give them a net positive surface charge. Their cytotoxicity and antibacterial activity were investigated, with negatively charged polyvinyl alcohol coated Se NPs as a control. Besides, these eADF4(κ16)-coated Se NPs were immobilized on the spider silk films, and the antibacterial activity of these films was investigated. Results: Compared to the negatively charged polyvinyl alcohol coated Se NPs, the positively charged eADF4(κ16)-coated Se NPs demonstrated a much higher bactericidal efficacy against the Gram-negative bacteria E. coli, with a minimum bactericidal concentration (MBC) approximately 50 times lower than that of negatively charged Se NPs. Cytotoxicity testing showed that the eADF4(κ16)-coated Se NPs are safe to both Balb/3T3 mouse embryo fibroblasts and HaCaT human skin keratinocytes up to 31 µg/mL, which is much higher than the MBC of these particles against E. coli (8 ± 1 µg/mL). In addition, antibacterial coatings were created by immobilising the eADF4(κ16)-coated Se NPs on positively charged spider silk films and these were shown to retain good bactericidal efficacy and overcome the issue of low particle stability in culture broth. It was found that these Se NPs needed to be released from the film surface in order to exert their antibacterial effects and this release can be regulated by the surface charge of the film, such as the change of the spider silk protein used. Conclusion: Overall, eADF4(κ16)-coated Se NPs are promising new antibacterial agents against life-threatening bacteria.


Assuntos
Antibacterianos/farmacologia , Nanopartículas/química , Proteínas Recombinantes/farmacologia , Selênio/farmacologia , Seda/farmacologia , Células 3T3 , Animais , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Contagem de Colônia Microbiana , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Nanopartículas/ultraestrutura , Tamanho da Partícula
7.
Nat Commun ; 11(1): 3651, 2020 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32686676

RESUMO

Lesion-based targeting strategies underlie cancer precision medicine. However, biological principles - such as cellular senescence - remain difficult to implement in molecularly informed treatment decisions. Functional analyses in syngeneic mouse models and cross-species validation in patient datasets might uncover clinically relevant genetics of biological response programs. Here, we show that chemotherapy-exposed primary Eµ-myc transgenic lymphomas - with and without defined genetic lesions - recapitulate molecular signatures of patients with diffuse large B-cell lymphoma (DLBCL). Importantly, we interrogate the murine lymphoma capacity to senesce and its epigenetic control via the histone H3 lysine 9 (H3K9)-methyltransferase Suv(ar)39h1 and H3K9me3-active demethylases by loss- and gain-of-function genetics, and an unbiased clinical trial-like approach. A mouse-derived senescence-indicating gene signature, termed "SUVARness", as well as high-level H3K9me3 lymphoma expression, predict favorable DLBCL patient outcome. Our data support the use of functional genetics in transgenic mouse models to incorporate basic biology knowledge into cancer precision medicine in the clinic.


Assuntos
Senescência Celular , Histona Metiltransferases , Linfoma Difuso de Grandes Células B , Células 3T3 , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Epigênese Genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Histona Metiltransferases/genética , Histona Metiltransferases/metabolismo , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Camundongos , Camundongos Transgênicos , Prognóstico
8.
Nat Commun ; 11(1): 2118, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32355211

RESUMO

ScRNA-seq has the ability to reveal accurate and precise cell types and states. Existing scRNA-seq platforms utilize bead-based technologies uniquely barcoding individual cells, facing practical challenges for precious samples with limited cell number. Here, we present a scRNA-seq platform, named Paired-seq, with high cells/beads utilization efficiency, cell-free RNAs removal capability, high gene detection ability and low cost. We utilize the differential flow resistance principle to achieve single cell/barcoded bead pairing with high cell utilization efficiency (95%). The integration of valves and pumps enables the complete removal of cell-free RNAs, efficient cell lysis and mRNA capture, achieving highest mRNA detection accuracy (R = 0.955) and comparable sensitivity. Lower reaction volume and higher mRNA capture and barcoding efficiency significantly reduce the cost of reagents and sequencing. The single-cell expression profile of mES and drug treated cells reveal cell heterogeneity, demonstrating the enormous potential of Paired-seq for cell biology, developmental biology and precision medicine.


Assuntos
RNA Mensageiro/química , Análise de Sequência de RNA , Análise de Célula Única/métodos , Células-Tronco/citologia , Células 3T3 , Animais , Antineoplásicos/farmacologia , Diferenciação Celular , Sistema Livre de Células , Células-Tronco Embrionárias/metabolismo , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Células K562 , Camundongos , Medicina de Precisão , Reprodutibilidade dos Testes
9.
Life Sci ; 255: 117827, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32450170

RESUMO

AIMS: Data suggest pharmacological treatment of depression with selective serotonin reuptake inhibitors (SSRI) may impair bone health. Our group has previously modeled compromised craniofacial healing after treatment with sertraline, a commonly prescribed SSRI, and hypothesized potential culprits: alterations in bone cells, collagen, and/or inflammation. Here we interrogate bone lineage cell alterations due to sertraline treatment as a potential cause of the noted compromised bone healing. MAIN METHODS: Murine pre-osteoblast, pre-osteoclast, osteoblast, and osteoclast cells were treated with clinically relevant concentrations of the SSRI. Studies focused on serotonin pathway targets, cell viability, apoptosis, differentiation, and the osteoblast/osteoclast feedback loop. KEY FINDINGS: All cells studied express neurotransmitters (e.g. serotonin transporter, SLC6A4, SSRI target) and G-protein-coupled receptors associated with the serotonin pathway. Osteoclasts presented the greatest native expression of Slc6a4 with all cell types exhibiting decreases in Slc6a4 expression after SSRI treatment. Pre-osteoclasts exhibited alteration to their differentiation pathway after treatment. Pre-osteoblasts and osteoclasts showed reduced apoptosis after treatment but showed no significant differences in functional assays. RANKL: OPG mRNA and protein ratios were decreased in the osteoblast lineage. Osteoclast lineage cells treated with sertraline demonstrated diminished TRAP positive cells when pre-exposed to sertraline prior to RANKL-induced differentiation. SIGNIFICANCE: These data suggest osteoclasts are a likely target of bone homeostasis disruption due to sertraline treatment, most potently through the osteoblast/clast feedback loop.


Assuntos
Osso e Ossos/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Inibidores de Captação de Serotonina/toxicidade , Células 3T3 , Animais , Apoptose/efeitos dos fármacos , Osso e Ossos/citologia , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Osteoblastos/citologia , Osteoclastos/citologia , Ligante RANK/metabolismo , Células RAW 264.7 , RNA Mensageiro/metabolismo
10.
Nat Commun ; 11(1): 2677, 2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32472050

RESUMO

Protein expression evolves under greater evolutionary constraint than mRNA levels, and translation efficiency represents a primary determinant of protein levels during stimuli adaptation. This raises the question as to the translatome remodelers that titrate protein output from mRNA populations. Here, we uncover a network of RNA-binding proteins (RBPs) that enhances the translation efficiency of glycolytic proteins in cells responding to oxygen deprivation. A system-wide proteomic survey of translational engagement identifies a family of oxygen-regulated RBPs that functions as a switch of glycolytic intensity. Tandem mass tag-pulse SILAC (TMT-pSILAC) and RNA sequencing reveals that each RBP controls a unique but overlapping portfolio of hypoxic responsive proteins. These RBPs collaborate with the hypoxic protein synthesis apparatus, operating as a translation efficiency checkpoint that integrates upstream mRNA signals to activate anaerobic metabolism. This system allows anoxia-resistant animals and mammalian cells to initiate anaerobic glycolysis and survive hypoxia. We suggest that an oxygen-sensitive RBP cluster controls anaerobic metabolism to confer hypoxia tolerance.


Assuntos
Anaerobiose/fisiologia , Hipóxia Celular/fisiologia , Glicólise/fisiologia , Proteínas de Ligação a RNA/metabolismo , Células 3T3 , Células A549 , Animais , Caenorhabditis elegans/metabolismo , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Células HCT116 , Humanos , Camundongos , Oxigênio/metabolismo , Células PC-3 , Biossíntese de Proteínas/fisiologia , Processamento de Proteína Pós-Traducional/genética , Proteômica , RNA Mensageiro/genética
11.
Nucleic Acids Res ; 48(W1): W218-W229, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32427338

RESUMO

Ribosome profiling (Ribo-seq) is a powerful technology for globally monitoring RNA translation; ranging from codon occupancy profiling, identification of actively translated open reading frames (ORFs), to the quantification of translational efficiency under various physiological or experimental conditions. However, analyzing and decoding translation information from Ribo-seq data is not trivial. Although there are many existing tools to analyze Ribo-seq data, most of these tools are designed for specific or limited functionalities and an easy-to-use integrated tool to analyze Ribo-seq data is lacking. Fortunately, the small size (26-34 nt) of ribosome protected fragments (RPFs) in Ribo-seq and the relatively small amount of sequencing data greatly facilitates the development of such a web platform, which is easy to manipulate for users with or without bioinformatic expertise. Thus, we developed RiboToolkit (http://rnabioinfor.tch.harvard.edu/RiboToolkit), a convenient, freely available, web-based service to centralize Ribo-seq data analyses, including data cleaning and quality evaluation, expression analysis based on RPFs, codon occupancy, translation efficiency analysis, differential translation analysis, functional annotation, translation metagene analysis, and identification of actively translated ORFs. Besides, easy-to-use web interfaces were developed to facilitate data analysis and intuitively visualize results. Thus, RiboToolkit will greatly facilitate the study of mRNA translation based on ribosome profiling.


Assuntos
Códon , Biossíntese de Proteínas , Ribossomos , Software , Células 3T3 , Animais , Estresse do Retículo Endoplasmático/genética , Camundongos , Anotação de Sequência Molecular , Fases de Leitura Aberta , RNA Mensageiro/metabolismo , Análise de Sequência de RNA
12.
Nat Protoc ; 15(5): 1612-1627, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32238950

RESUMO

'Adult' or 'somatic' stem cells harbor an intrinsic ability to regenerate tissues. Heterogeneity of such stem cells along the gastrointestinal tract yields the known segmental specificity of this organ and may contribute to the pathology of certain enteric conditions. Here we detail technology for the generation of 'libraries' of clonogenic cells from 1-mm-diamter endoscopic biopsy samples from the human gastrointestinal tract. Each of the 150-300 independent clones in a typical stem cell library can be clonally expanded to billions of cells in a few weeks while maintaining genomic stability and the ability to undergo multipotent differentiation to the specific epithelia from which the sample originated. The key to this methodology is the intrinsic immortality of normal intestinal stem cells (ISCs) and culture systems that maintain them as highly immature, ground-state ISCs marked by a single-cell clonogenicity of 70% and a corresponding 250-fold proliferative advantage over spheroid technologies. Clonal approaches such as this enhance the resolution of molecular genetics, make genome editing easier, and may be useful in regenerative medicine, unravelling heterogeneity in disease, and facilitating drug discovery.


Assuntos
Células-Tronco Adultas/fisiologia , Técnicas de Cultura de Células , Mucosa Intestinal/citologia , Células 3T3 , Animais , Biópsia , Endoscopia Gastrointestinal , Humanos , Camundongos
13.
Prostate ; 80(9): 698-714, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32348616

RESUMO

BACKGROUND: Osteoblastic bone metastasis represents the most common complication in men with prostate cancer (PCa). During progression and bone metastasis, PCa cells acquire properties similar to bone cells in a phenomenon called osteomimicry, which promotes their ability to metastasize, proliferate, and survive in the bone microenvironment. The mechanism of osteomimicry resulting in osteoblastic bone metastasis is unclear. METHODS: We developed and characterized a novel canine prostatic cancer cell line (LuMa) that will be useful to investigate the relationship between osteoblastic bone metastasis and osteomimicry in PCa. The LuMa cell line was established from a primary prostate carcinoma of a 13-year old mixed breed castrated male dog. Cell proliferation and gene expression of LuMa were measured and compared to three other canine prostatic cancer cell lines (Probasco, Ace-1, and Leo) in vitro. The effect of LuMa cells on calvaria and murine preosteoblastic (MC3T3-E1) cells was measured by quantitative reverse-transcription polymerase chain reaction and alkaline phosphatase assay. LuMa cells were transduced with luciferase for monitoring in vivo tumor growth and metastasis using different inoculation routes (subcutaneous, intratibial [IT], and intracardiac [IC]). Xenograft tumors and metastases were evaluated using radiography and histopathology. RESULTS: After left ventricular injection, LuMa cells metastasized to bone, brain, and adrenal glands. IT injections induced tumors with intramedullary new bone formation. LuMa cells had the highest messenger RNA levels of osteomimicry genes (RUNX2, RANKL, and Osteopontin [OPN]), CD44, E-cadherin, and MYOF compared to Ace-1, Probasco, and Leo cells. LuMa cells induced growth in calvaria defects and modulated gene expression in MC3T3-E1 cells. CONCLUSIONS: LuMa is a novel canine PCa cell line with osteomimicry and stemness properties. LuMa cells induced osteoblastic bone formation in vitro and in vivo. LuMa PCa cells will serve as an excellent model for studying the mechanisms of osteomimicry and osteoblastic bone and brain metastasis in prostate cancer.


Assuntos
Neoplasias Ósseas/secundário , Linhagem Celular Tumoral/patologia , Osteoblastos/patologia , Neoplasias da Próstata/patologia , Células 3T3 , Animais , Neoplasias Ósseas/genética , Diferenciação Celular/fisiologia , Processos de Crescimento Celular/fisiologia , Cães , Xenoenxertos , Masculino , Camundongos , Camundongos Nus , Metástase Neoplásica , Células-Tronco Neoplásicas/patologia , Neoplasias da Próstata/genética , Células Tumorais Cultivadas
14.
Nat Commun ; 11(1): 1994, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32332736

RESUMO

Gas1 and Boc/Cdon act as co-receptors in the vertebrate Hedgehog signalling pathway, but the nature of their interaction with the primary Ptch1/2 receptors remains unclear. Here we demonstrate, using primordial germ cell migration in mouse as a developmental model, that specific hetero-complexes of Ptch2/Gas1 and Ptch1/Boc mediate the process of Smo de-repression with different kinetics, through distinct modes of Hedgehog ligand reception. Moreover, Ptch2-mediated Hedgehog signalling induces the phosphorylation of Creb and Src proteins in parallel to Gli induction, identifying a previously unknown Ptch2-specific signal pathway. We propose that although Ptch1 and Ptch2 functionally overlap in the sequestration of Smo, the spatiotemporal expression of Boc and Gas1 may determine the outcome of Hedgehog signalling through compartmentalisation and modulation of Smo-downstream signalling. Our study identifies the existence of a divergent Hedgehog signal pathway mediated by Ptch2 and provides a mechanism for differential interpretation of Hedgehog signalling in the germ cell niche.


Assuntos
Quimiotaxia/genética , Regulação da Expressão Gênica no Desenvolvimento , Células Germinativas/fisiologia , Proteínas Hedgehog/metabolismo , Receptor Patched-1/metabolismo , Receptor Patched-2/metabolismo , Células 3T3 , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Embrião de Mamíferos , Feminino , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Técnicas de Inativação de Genes , Imunoglobulina G/metabolismo , Microscopia Intravital , Masculino , Camundongos , Camundongos Transgênicos , Técnicas de Cultura de Órgãos , Receptor Patched-1/genética , Receptores de Superfície Celular/metabolismo , Transdução de Sinais/genética , Receptor Smoothened/metabolismo , Imagem com Lapso de Tempo , Quinases da Família src/metabolismo
15.
Metabolism ; 108: 154250, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32335074

RESUMO

BACKGROUND: Chronic steroid treatment causes an increase in visceral adiposity and osteoporosis. It is believed that steroids may alter a balance between differentiation of mesenchymal stem cells (MSCs) into either adipocytes or osteoblasts; however, the detailed molecular mechanisms are unclear. We previously identified Dexras1 as a critical factor that potentiates adipogenesis in response to glucocorticoids. Thus, in this study, we investigated the role of Dexras1 in maintaining the balance between chronic steroid treatment-associated adipogenesis and osteoporosis. MATERIAL AND METHODS: We treated wild type (WT) and Dexras1 knockout (KO) mice with dexamethasone for five weeks followed by 60% HFD for additional two weeks with dexamethasone. The changes of glucocorticoid-induced body weight gain and osteoporosis were analyzed. Bone marrow derived stromal cells (BMSCs) and mouse embryonic fibroblasts (MEFs) extracted from WT and Dexras1 KO mice, as well as MC3T3-E1 pre-osteoblasts and osteoclasts differentiated from RAW264.7 were analyzed to further define the role of Dexras1 in osteoblasts and osteoclasts. RESULTS: Dual-energy X-ray absorptiometry and micro-computed tomography analyses in murine femurs revealed that Dexras1 deficiency was associated with increased osteogenesis, concurrent with reduced adipogenesis. Furthermore, Dexras1 deficiency promoted osteogenesis of BMSCs and MEFs in vitro, suggesting that Dexras1 deficiency prevents steroid-induced osteoporosis. We also observed that Dexras1 downregulated SMAD signaling pathways, which reduced the osteogenic differentiation capacity of pre-osteoblast MC3T3-E1 cells into mature osteoblasts. CONCLUSION: We propose that Dexras1 is critical for maintaining the equilibrium between adipogenesis and osteogenesis upon steroid treatment.


Assuntos
Adipogenia/fisiologia , Osteogênese/fisiologia , Proteínas ras/metabolismo , Células 3T3 , Adipócitos/metabolismo , Animais , Diferenciação Celular/fisiologia , Linhagem Celular , Fêmur/metabolismo , Glucocorticoides/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteoporose/metabolismo , Células RAW 264.7 , Transdução de Sinais/fisiologia
16.
Sheng Li Xue Bao ; 72(2): 175-180, 2020 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-32328611

RESUMO

The present study was aimed to clarify the signaling molecular mechanism by which fibroblast growth factor 21 (FGF21) regulates leptin gene expression in adipocytes. Differentiated 3T3-F442A adipocytes were used as study object. The mRNA expression level of leptin was detected by fluorescence quantitative RT-PCR. The phosphorylation levels of proteins of signal transduction pathways were detected by Western blot. The results showed that FGF21 significantly down-regulated the mRNA expression level of leptin in adipocytes, and FGF21 receptor inhibitor BGJ-398 could completely block this effect. FGF21 up-regulated the phosphorylation levels of ERK1/2 and AMPK in adipocytes. Either ERK1/2 inhibitor SCH772984 or AMPK inhibitor Compound C could partially block the inhibitory effect of FGF21, and the combined application of these two inhibitors completely blocked the effect of FGF21. Neither PI3K inhibitor LY294002 nor Akt inhibitor AZD5363 affected the inhibitory effect of FGF21 on leptin gene expression. These results suggest that FGF21 may inhibit leptin gene expression by activating ERK1/2 and AMPK signaling pathways in adipocytes.


Assuntos
Adipócitos/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Leptina/metabolismo , Células 3T3 , Adenilato Quinase , Animais , Regulação para Baixo , Sistema de Sinalização das MAP Quinases , Camundongos , Fosforilação , Transdução de Sinais
17.
J Oleo Sci ; 69(5): 487-493, 2020 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-32281564

RESUMO

Obesity, a lifestyle disease resulting from excessive caloric intake and insufficient physical activity, results in a state of chronic inflammation. A food ingredient that suppresses chronic inflammation could help prevent associated diseases. Sweet basil (Ocimum basilicum L.) is a herb from the Lamiaceae family with some reported anti-inflammatory effects. Via this in vitro study, we aimed to investigate whether sweet basil exerts anti-inflammatory effects in obese patients. Fresh sweet basil leaves were freeze-dried and powered. After that, this was extracted with 80% methanol. After 3T3-L1 adipocytes were cultured with sweet basil extracts at final concentrations of either 5 or 25 µg/mL for 24h, RAW264.7 macrophages were seeded onto this adipocytes and co-cultured for 12h. We determined the effects of sweet basil extracts on inflammatory cytokine expression by real-time PCR or western blotting. Sweet basil extracts reduced the expression of inflammatory cytokine mRNA induced by co-culture, including that of IL-6 (Il6), IL-1ß (Il1b), TNF-α (Tnf), and CCL2 (Ccl2). In addition, sweet basil extracts suppressed the mRNA expression of NF-κB (Nfκb1), a transcription factor of inflammatory cytokines. In an investigation of costimulatory CD137 (Tnfrsf9)/CD137L inflammatory signaling, a member of the TNF super-family, sweet basil extracts inhibited Tnfrsf9 expression induced by the co-culture. Therefore, the results of this study indicated that sweet basil extracts have an anti-inflammatory effect against adipocyte-induced inflammation, possibly through suppression of Tnfrsf9 expression.


Assuntos
Adipócitos/metabolismo , Anti-Inflamatórios , Técnicas de Cocultura , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Ocimum/química , Extratos Vegetais/farmacologia , Células 3T3 , Animais , Citocinas/genética , Expressão Gênica/efeitos dos fármacos , Camundongos , NF-kappa B/genética , NF-kappa B/metabolismo , Células RAW 264.7 , RNA Mensageiro/metabolismo , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
18.
PLoS Negl Trop Dis ; 14(3): e0008068, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32163414

RESUMO

Trypanosoma cruzi parasites utilise de novo pyrimidine biosynthesis to produce DNA and survive within mammalian host cells. This pathway can be hijacked to assess the replication of intracellular parasites with the exogenous addition of a DNA specific probe. To identify suitable probe compounds for this application, a collection of pyrimidine nucleoside analogues was assessed for incorporation into T. cruzi intracellular amastigote DNA using image-based technology and script-based analysis. Associated mammalian cell toxicity of these compounds was also determined against both the parasite host cells (3T3 cells) and HEK293 cells. Incorporation of 5-ethynyl-2'-deoxyuridine (EdU) into parasite DNA was the most effective of the probes tested, with minimal growth inhibition observed following either two or four hours EdU exposure. EdU was subsequently utilised as a DNA probe, followed by visualisation with click chemistry to a fluorescent azide, to assess the impact of drugs and compounds with previously demonstrated activity against T. cruzi parasites, on parasite replication. The inhibitory profiles of these molecules highlight the benefit of this approach for identifying surviving parasites post-treatment in vitro and classifying compounds as either fast or slow-acting. F-ara-EdU resulted in <50% activity observed against T. cruzi amastigotes following 48 hours incubation, at 73 µM. Collectively, this supports the further development of pyrimidine nucleosides as chemical probes to investigate replication of the parasite T. cruzi.


Assuntos
Antiprotozoários/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Testes de Sensibilidade Parasitária/métodos , Nucleosídeos de Pirimidina/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/crescimento & desenvolvimento , Células 3T3 , Animais , Antiprotozoários/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células HEK293 , Humanos , Camundongos , Nucleosídeos de Pirimidina/toxicidade
19.
Acta Diabetol ; 57(7): 883-890, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32124076

RESUMO

AIMS/HYPOTHESIS: Impaired wound healing significantly impacts morbidity and mortality in diabetic patients, necessitating the development of novel treatments to improve the wound healing process. We here investigated the topical use of acellular embryonic stem cell extracts (EXTs) in wound healing in diabetic db/db mice. METHODS: Wounds were induced in diabetic db/db mice, which were subsequently treated with EXTs, with 3T3 fibroblast cell line protein extracts (3T3XTs) or with saline as a control. Pathology and mechanistic assays were then performed. RESULTS: The in vivo topical administration of EXTs facilitates wound closure, contraction and re-epithelialization. Moreover, EXTs reduced the number of wound-infiltrating CD45+ inflammatory cells and increased the rate of repair and of angiogenesis as compared to controls. Interestingly, the EXT effect was partly enhanced by the use of a collagen-based biocompatible scaffold. In vivo, topical administration of EXTs increased the percentage of regulatory T cells in the wounded tissue, while in vitro EXT treatment reduced T cell-mediated IFN-γ production. Proteomic screening revealed 82 proteins differentially segregating in EXTs as compared to 3T3 extracts, with APEX1 identified as a key player for the observed immunomodulatory effect of EXTs. CONCLUSIONS: EXTs are endowed with immunoregulatory and anti-inflammatory properties; their use improves wound healing in diabetic preclinical models.


Assuntos
Extratos Celulares/farmacologia , Extratos Celulares/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/fisiopatologia , Células-Tronco Embrionárias/química , Cicatrização/efeitos dos fármacos , Células 3T3 , Animais , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/patologia , Células-Tronco Embrionárias/metabolismo , Imunidade Inata/efeitos dos fármacos , Masculino , Camundongos , Camundongos Transgênicos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/fisiopatologia , Proteoma/análise , Proteoma/metabolismo , Proteômica , Cicatrização/fisiologia
20.
Genes Dev ; 34(7-8): 495-510, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32139423

RESUMO

Obesity-induced diabetes affects >400 million people worldwide. Uncontrolled lipolysis (free fatty acid release from adipocytes) can contribute to diabetes and obesity. To identify future therapeutic avenues targeting this pathway, we performed a high-throughput screen and identified the extracellular-regulated kinase 3 (ERK3) as a hit. We demonstrated that ß-adrenergic stimulation stabilizes ERK3, leading to the formation of a complex with the cofactor MAP kinase-activated protein kinase 5 (MK5), thereby driving lipolysis. Mechanistically, we identified a downstream target of the ERK3/MK5 pathway, the transcription factor FOXO1, which promotes the expression of the major lipolytic enzyme ATGL. Finally, we provide evidence that targeted deletion of ERK3 in mouse adipocytes inhibits lipolysis, but elevates energy dissipation, promoting lean phenotype and ameliorating diabetes. Thus, ERK3/MK5 represents a previously unrecognized signaling axis in adipose tissue and an attractive target for future therapies aiming to combat obesity-induced diabetes.


Assuntos
Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/fisiopatologia , Metabolismo Energético/genética , Lipólise/genética , Proteína Quinase 6 Ativada por Mitógeno/genética , Proteína Quinase 6 Ativada por Mitógeno/metabolismo , Obesidade/complicações , Células 3T3 , Tecido Adiposo/enzimologia , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos , Proteína Forkhead Box O1/metabolismo , Deleção de Genes , Células HEK293 , Humanos , Hipoglicemiantes/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lipase/genética , Lipase/metabolismo , Camundongos , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/genética
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