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1.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(6): 678-683, 2020 Jun 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-32879125

RESUMO

OBJECTIVES: To explore the difference in odontoblast differentiation capacity between stem cells from human exfoliated deciduous teeth (SHED) and dental pulp stem cells (DPSCs), and to examine the expression level of ephrinB1 in odontoblast differentiation of these stem cells. METHODS: The stems cells were divided into a SHED group and a DPSCs group. After odontoblast differentiation induction, the above 2 groups were also randomly divided into a 3 d group and a 7 d group, respectively.The calcium deposition was detected by alkaline phosphatase (ALP) staining and alizarin red staining.The mRNA and protein expressions of ephrinB1, dentin matrix protein-1 (DMP-1) and dentin sialophosphoprotein (DSPP) were detected by real-time PCR and Western blotting. RESULTS: ALP staining and alizarin red staining showed that there was stronger mineralization capacity in the SHED group than that in the DPSCs group. The relative mRNA and protein expressions of DMP-1, DSPP, and ephrinB1 in the SHED group were higher than those in the DPSCs group except for the protein expression of DMP-1 in the SHED 3 d group (all P<0.05). CONCLUSIONS: SHED has stronger odontoblast differentiation capacity than DPSCs. In addition, ephrinB1 may be involved in the processes of odontoblast differentiation in the SHED and DPSCs.


Assuntos
Odontoblastos , Osteogênese , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Polpa Dentária , Humanos , Células-Tronco , Dente Decíduo
2.
J Endod ; 46(9S): S56-S62, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32950196

RESUMO

INTRODUCTION: The maintenance of a stem cell pool is imperative to enable healing processes in the dental pulp tissue throughout life. As such, knowing mechanisms underlying stem cell self-renewal is critical to understand pulp pathophysiology and pulp regeneration. The purpose of this study was to evaluate the impact of stem cell factor (SCF) signaling through its receptor tyrosine kinase (c-Kit) on the self-renewal of human dental pulp stem cells (hDPSCs). METHODS: The hDPSCs were stably transduced with lentiviral vectors expressing shRNA-c-Kit or vector control. The impact of the SCF/c-Kit axis on hDPSC self-renewal was evaluated by using a pulpsphere assay in low attachment conditions and by evaluating the expression of polycomb complex protein Bmi-1 (master regulator of self-renewal) by Western blot and flow cytometry. RESULTS: The c-Kit-silenced hDPSCs formed fewer pulpspheres when compared with hDPSCs transduced with control vector (P < .05). Evaluation of pulpsphere morphology revealed the presence of 3 distinct sphere types, ie, holospheres, merospheres, and paraspheres. Although c-Kit silencing decreased the number of holospheres compared with control cells (P < .05), it had no effect on the number of merospheres and paraspheres. Recombinant human stem cell factor (rhSCF) increased the number of holospheres (P < .05) and induced dose-dependent Bmi-1 expression in hDPSCs. As expected, the inductive capacity of rhSCF on Bmi-1 expression and fraction of Bmi-1-positive cells was inhibited when we silenced c-Kit in hDPSCs. CONCLUSIONS: These results unveiled the role of SCF/c-Kit signaling on the self-renewal of hDPSCs and suggested that this pathway enables long-term maintenance of stem cell pools in human dental pulps.


Assuntos
Polpa Dentária , Células-Tronco , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , Transdução de Sinais
3.
Korean J Parasitol ; 58(4): 393-402, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32871633

RESUMO

Toxoplasma gondii is an intracellular parasite that causes severe disease when the infection occurs during pregnancy. Adenosine is a purine nucleoside involved in numerous physiological processes; however, the role of adenosine receptors in T. gondii-induced trophoblast cell function has not been investigated until now. The goal of the present study was to evaluate the intracellular signaling pathways regulated by adenosine receptors using a HTR-8/SVneo trophoblast cell model of T. gondii infection. HTR8/SVneo human extravillous trophoblast cells were infected with or without T. gondii and then evaluated for cell morphology, intracellular proliferation of the parasite, adenosine receptor expression, TNF-α production and mitogen-activated protein (MAP) kinase signaling pathways triggered by adenosine A3 receptor (A3AR). HTR8/SVneo cells infected with T. gondii exhibited an altered cytoskeletal changes, an increased infection rate and reduced viability in an infection time-dependent manner. T. gondii significantly promoted increased TNF-α production, A3AR protein levels and p38, ERK1/2 and JNK phosphorylation compared to those observed in uninfected control cells. Moreover, the inhibition of A3AR by A3AR siRNA transfection apparently suppressed the T. gondii infection-mediated upregulation of TNF-α, A3AR production and MAPK activation. In addition, T. gondii-promoted TNF-α secretion was dramatically attenuated by pretreatment with PD098059 or SP600125. These results indicate that A3AR-mediated activation of ERK1/2 and JNK positively regulates TNF-α secretion in T. gondii-infected HTR8/SVneo cells.


Assuntos
MAP Quinase Quinase 4/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Receptor A3 de Adenosina/fisiologia , Toxoplasmose/metabolismo , Trofoblastos/metabolismo , Trofoblastos/parasitologia , Fator de Necrose Tumoral alfa/metabolismo , Células Cultivadas , Humanos
5.
BMC Dermatol ; 20(1): 6, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32867747

RESUMO

BACKGROUND: Specific species of ceramides (Cer), major constituents of lipids in the stratum corneum (SC), are decreased and are correlated with SC barrier and water-holding functions in the skin of patients with atopic dermatitis (AD) or psoriasis (Pso). However, possible correlations between Cer subclass ratios and skin properties in barrier-disrupted skin and in healthy skin remain unclear. The objective of this study was to identify a new marker to evaluate skin properties and epidermal differentiation in SC not only in barrier-disrupted skin but also in healthy skin. METHODS: The Cer subclass ratios in the SC of healthy control subjects and in patients with AD or Pso were evaluated. Correlations with candidate markers and facial skin features of healthy Japanese females (20-74 years old, n = 210) were investigated. Variations of markers during epidermal differentiation were studied in human epidermis and in cultured keratinocytes. RESULTS: The ratios of Cer [NP]/[NS], Cer [NH]/[NS], Cer [NP]/[AS], Cer [NH]/[NS], Cer [NDS]/[AS], Cer [AH]/[AS] and Cer [EOP]/[AS] showed significant differences between non-lesional skin of AD patients and normal skin of healthy control subjects, as well as Pso patients and their healthy control subjects. The Cer [NP]/[NS] ratio was correlated with SC functional parameters (transepidermal water loss and capacitance) and with skin appearance (texture, scaling and color) even in the cheek skin of healthy female subjects. The Cer [NP]/[NS] ratio in the SC was approximately 18-times higher than in living keratinocytes, and it increased as they differentiated. CONCLUSIONS: The Cer [NP]/[NS] ratio in the SC is a potential marker for skin properties and epidermal differentiation in barrier-disrupted skin as well as in healthy skin.


Assuntos
Ceramidas/análise , Dermatite Atópica/patologia , Epiderme/química , Psoríase/patologia , Adulto , Idoso , Biomarcadores/análise , Estudos de Casos e Controles , Diferenciação Celular , Células Cultivadas , Dermatite Atópica/diagnóstico , Epiderme/patologia , Feminino , Humanos , Queratinócitos/química , Queratinócitos/citologia , Lipídeos/análise , Pessoa de Meia-Idade , Psoríase/diagnóstico , Adulto Jovem
6.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(5): 640-646, 2020 May 30.
Artigo em Chinês | MEDLINE | ID: mdl-32897197

RESUMO

OBJECTIVE: To clarify the molecular signaling mechanism underlying the inhibitory effect of metformin on transforming growth factor-ß1 (TGF-ß1)-stimulated collagen I production in rat biliary fibroblasts. METHODS: Primary biliary fibroblasts were isolated under aseptic condition from 50 Sprague-Dawley rats (half male and half female), and microscopic observation identified no obvious difference in the morphology or viability of the cells from rats with different sexes or body weight. The cells were treated with TGF-ß1 (10 ng/mL), Smad3 siRNA+TGF-ß1, CTGF siRNA+TGF-ß1, metformin (10 mmol/L)+ TGF-ß1, or Compound C (10 µmol/L)+metformin+TGF-ß1. The expressions of CTGF and collagen I in the treated cells were determined using ELISA kit or Western blotting; the phorsphorylated and total Smad3 and AMPK expressions were detected using immunoblotting. RESULTS: TGF-ß1 time- and dose-dependently induced collagen I production in rat biliary fibroblasts. The activated AMPK by metformin dose-dependently inhibited TGF-ß1-induced collagen I production. Pre-incubation of cells with the AMPK inhibitor Compound C restored the inhibitory effect of AMPK on TGF-ß1-induced collagen I secretion (P < 0.01). Activation of AMPK by metformin significantly reduced TGF-ß1-induced collagen I production by suppressing Smad3-driven CTGF expression (P < 0.01), and the application of Compound C reversed such changes in the fibroblasts (P < 0.01). CONCLUSIONS: Metformin inhibits TGF-ß1-stimulated collagen I production by activating AMPK and inhibiting Smad3- driven CTGF expression in rat biliary fibroblasts.


Assuntos
Fibroblastos , Animais , Células Cultivadas , Colágeno , Feminino , Masculino , Metformina , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Proteína Smad3 , Fator de Crescimento Transformador beta1
7.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(4): 499-505, 2020 Apr 30.
Artigo em Chinês | MEDLINE | ID: mdl-32895132

RESUMO

OBJECTIVE: To explore the effects of olmesartan on age-associated migration and invasion capacities and microRNA (miRAN) axis in human aortic vascular smooth muscle cells (HA-VSMCs). METHODS: Cultured HA-VSMCs were divided into control group, bleomycin-mediated senescence (BLM) group and bleomycin + olmesartan treatment group. Wound-healing assay and Boyden chambers invasion assay were used to assess the changes in migration and invasion of the cells, gelatin zymography was used to analyze matrix metalloproteinase-2 (MMP-2) activation in the cells. The differentially expressed miRNAs were identified by miRNA microarray assay and validated by quantitative real-time PCR. MiR-3133 inhibitor was used to examine the effects of molecular manipulation of olmesartan on age-associated migration and invasion and MMP-2 activation in the cells. RESULTS: Compared with those of the control group, the percentage of the repopulated cells and the number of cells crossing the basement membrane increased significantly in BLM group [(78.43±12.76)% vs (42.47±7.22)%, P < 0.05; 33.33±5.51 vs 13.00±4.36, P < 0.05]. A significant increase of MMP-2 activation was found in BLM group as compared with the control group (1.66 ± 0.27 vs 0.87 ± 0.13, P < 0.05). Olmesartan significantly inhibited BLM-induced enhancement of cell migration and invasion and MMP-2 secretion in the cells. MiR-3133 was significantly downregulated in BLM group and upregulated in olmesartan group. Transfection with miR-3133 inhibitor significantly reversed the effects of olmesartan on age-associated migration and invasion of the cells [(85.87±7.39)% vs (49.77±3.05)%; 34.67±2.31 vs 20.00±4.58, P < 0.05] and MMP-2 activation in the cells (1.76±0.19 vs 0.94±0.10, P < 0.05). CONCLUSIONS: Olmesartan inhibits the migration and invasion of ageassociated HA-VSMCs probably by upregulating of the miR-3133 axis.


Assuntos
MicroRNAs/genética , Músculo Liso Vascular , Movimento Celular , Proliferação de Células , Células Cultivadas , Humanos , Imidazóis , Metaloproteinase 2 da Matriz , Miócitos de Músculo Liso , Tetrazóis
8.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(8): 1119-1126, 2020 Aug 30.
Artigo em Chinês | MEDLINE | ID: mdl-32895177

RESUMO

OBJECTIVE: To explore the effect of Danggui Niantong decoction (DGNTD) on cell apoptosis and TNF receptor super family 6 (Fas)/caspase-8 pathway in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS). METHODS: FLS isolated from the synovial tissue of RA patients were cultured and identified using immunofluorescence staining. The cells were treated with 10% blank serum (blank control group), 10% sera containing low, moderate or high doses of DGNTD, or 20 µmol/mL KR-33493 (a Fas inhibitor) combined with 10% serum containing high-dose DGNTD. MTT assay was used to detect the proliferation of the cells after the treatments. Apoptosis of the cells was detected at 48 h in each group using Hoechst 33342 staining and flow cytometry with annexin V-FITC/PI staining. The mRNA and protein expressions of Fas, FADD, caspase-8 and caspase-3 in the cells at 48 h were detected using qPCR and Western blotting. RESULTS: Immunofluorescence staining identified the cultured cells as FLS. Treatment with DGNTD-containing sera significantly inhibited the proliferation of FLS, and the inhibitory effects were enhanced as the dose and intervention time increased (P < 0.05). Hoechst 33342 staining and flow cytometry showed that the sera containing different doses of DGNTD significantly promoted apoptosis of FLS (P < 0.05). The expression levels of Fas, FADD, caspase-8, and caspase-3 at both mRNA and protein levels were significantly increased in the cells after treatment with different doses of DGNTD-containing sera (P < 0.05). The application of KR-33493 obviously reversed the effects of DGNTD on the FLS (P < 0.05). CONCLUSIONS: DGNTD can induce apoptosis of the FLS by activating Fas/caspase-8 signaling pathway.


Assuntos
Artrite Reumatoide , Sinoviócitos , Apoptose , Caspase 8 , Proliferação de Células , Células Cultivadas , Fibroblastos , Membrana Sinovial
9.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(8): 1134-1140, 2020 Aug 30.
Artigo em Chinês | MEDLINE | ID: mdl-32895184

RESUMO

OBJECTIVE: To explore whether thrombopoietin (TPO) can rescue megakaryopoiesis by protecting bone marrowderived endothelial progenitor cells (BM-EPCs) in patients receiving chemotherapy for hematological malignancies. METHODS: Bone marrow samples were collected from 23 patients with hematological malignancies 30 days after chemotherapy and from 10 healthy volunteers. BM-EPCs isolated from the samples were identified by staining for CD34, CD309 and CD133, and their proliferation in response to treatment with TPO was assessed using CCK8 assay. DiL-Ac-LDL uptake and FITC-UEA-I binding assay were performed to evaluate the amount of BM-EPCs from the subjects. Tube-formation and migration experiments were used for functional assessment of the BM-EPCs. The BM-EPCs with or without TPO treatment were co-cultured with human megakaryocytes, and the proliferation of the megakaryocytes was detected with flow cytometry. RESULTS: Flow cytometry indicated that the TPO-treated cells had high expressions of CD34, CD133, and CD309. CCK8 assay demonstrated that TPO treatment enhanced the proliferation of the BM-EPCs, and the optimal concentration of TPO was 100 µg/L. Double immunofluorescence assay indicated that the number of BM-EPC was significantly higher in TPO-treated group than in the control group. The TPO-treated BM-EPCs exhibited stronger tube-formation and migration abilities (P < 0.05) and more significantly enhanced the proliferation of co-cultured human megakaryocytes than the control cells (P < 0.05). CONCLUSIONS: TPO can directly stimulate megakaryopoiesis and reduce hemorrhage via protecting the function of BM-EPCs in patients following chemotherapy for hematological malignancies.


Assuntos
Medula Óssea , Neoplasias Hematológicas , Células da Medula Óssea , Células Cultivadas , Humanos , Megacariócitos , Trombopoetina
10.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 34(9): 1170-1176, 2020 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-32929912

RESUMO

Objective: To investigate the effects of three-dimensional (3D) printed Ti6Al4V-4Cu alloy on inflammation and osteogenic gene expression in mouse bone marrow mesenchymal stem cells (BMSCs) and mouse mononuclear macrophage line RAW264.7. Methods: Ti6Al4V and Ti6Al4V-4Cu alloys were prepared by selective laser melting, and the extracts of the two materials were prepared according to the biological evaluation standard of medical devices. The effects of two kinds of extracts on the proliferation of mouse BMSCs and mouse RAW264.7 cells were detected by cell counting kit 8 method. After co-cultured with mouse BMSCs for 3 days, the expression of osteogenesis- related genes [collagen type Ⅰ (Col-Ⅰ), alkaline phosphatase (ALP), Runx family transcription factor 2 (Runx-2), osteoprotegerin (OPG), and osteopontin (OPN)] were detected by real-time fluorescence quantitative PCR. After co-cultured with mouse RAW264.7 cells for 1 day, the expressions of inflammation-related genes [interleukin 4 (IL-4) and nitric oxide synthase 2 (iNOS)] were detected by real-time fluorescence quantitative PCR, and the supernatants of the two groups were collected to detect the secretion of vascular endothelial growth factor a (VEGF-a) and bone morphogenetic protein 2 (BMP-2) by ELISA. The osteogenic conditioned medium were prepared with the supernatants of the two groups and co-cultured with BMSCs for 3 days. The expressions of osteogenesis-related genes (Col-Ⅰ, ALP, Runx-2, OPG, and OPN) were detected by real-time fluorescence quantitative PCR. Results: Compared with Ti6Al4V alloy extract, Ti6Al4V-4Cu alloy extract had no obvious effect on the proliferation of BMSCs and RAW264.7 cells, but it could promote the expression of OPG mRNA in BMSCs, reduce the expression of iNOS mRNA in RAW264.7 cells, and promote the expression of IL-4 mRNA. It could also promote the secretions of VEGF-a and BMP-2 in RAW264.7 cells. Ti6Al4V-4Cu osteogenic conditioned medium could promote the expressions of Col-Ⅰ, ALP, Runx-2, OPG, and OPN mRNAs in BMSCs. The differences were all significant ( P<0.05). Conclusion: 3D printed Ti6Al4V-4Cu alloy can promote RAW264.7 cells to secret VEGF-a and BMP-2 by releasing copper ions, thus promoting osteogenesis through bone immune regulation, which lays a theoretical foundation for the application of metal prosthesis.


Assuntos
Ligas , Osteogênese , Animais , Células da Medula Óssea , Proteína Morfogenética Óssea 2/metabolismo , Diferenciação Celular , Células Cultivadas , Regulação da Expressão Gênica , Camundongos , Titânio , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
Nat Commun ; 11(1): 4367, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32868763

RESUMO

Invariant natural killer T (iNKT), mucosal-associated invariant T (MAIT), and γδ T cells are innate T cells that acquire memory phenotype in the thymus and share similar biological characteristics. However, how their effector differentiation is developmentally regulated is still unclear. Here, we identify analogous effector subsets of these three innate T cell types in the thymus that share transcriptional profiles. Using single-cell RNA sequencing, we show that iNKT, MAIT and γδ T cells mature via shared, branched differentiation rather than linear maturation or TCR-mediated instruction. Simultaneous TCR clonotyping analysis reveals that thymic maturation of all three types is accompanied by clonal selection and expansion. Analyses of mice deficient of TBET, GATA3 or RORγt and additional in vivo experiments corroborate the predicted differentiation paths, while human innate T cells from liver samples display similar features. Collectively, our data indicate that innate T cells share effector differentiation processes in the thymus.


Assuntos
Diferenciação Celular , Imunidade Inata , Linfócitos T/metabolismo , Timo/imunologia , Animais , Células Cultivadas , Seleção Clonal Mediada por Antígeno , Humanos , Fígado/citologia , Fígado/imunologia , Ativação Linfocitária , Camundongos , Células T Invariáveis Associadas à Mucosa/metabolismo , Células T Matadoras Naturais/metabolismo , Análise de Sequência de RNA , Análise de Célula Única , Células Th17/metabolismo , Timo/citologia
12.
Dis Model Mech ; 13(9)2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887790

RESUMO

The spread of the novel virus SARS coronavirus 2 (SARS-CoV-2) was explosive, with cases first identified in December 2019, and >22 million people infected and >775,000 deaths as of August 2020. SARS-CoV-2 can cause severe respiratory disease in humans leading to coronavirus disease 2019 (COVID-19). The development of effective clinical interventions, such as antivirals and vaccines that can limit or even prevent the burden and spread of SARS-CoV-2, is a global health priority. Testing of leading antivirals, monoclonal antibody therapies and vaccines against SARS-CoV-2 will require robust animal and cell models of viral pathogenesis. In this Special Article, we discuss the cell-based and animal models of SARS-CoV-2 infection and pathogenesis that have been described as of August 2020. We also outline the outstanding questions for which researchers can leverage animal and cell-based models to improve our understanding of SARS-CoV-2 pathogenesis and protective immunity. Taken together, the refinement of models of SARS-CoV-2 infection will be critical to guide the development of therapeutics and vaccines against SARS-CoV-2 to end the COVID-19 pandemic.


Assuntos
Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Animais , Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Células Cultivadas , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/prevenção & controle , Modelos Animais de Doenças , Interações entre Hospedeiro e Microrganismos , Humanos , Pandemias , Pneumonia Viral/tratamento farmacológico , Especificidade da Espécie , Técnicas de Cultura de Tecidos , Vacinas Virais/uso terapêutico
13.
J Exp Med ; 217(12)2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-32886755

RESUMO

COVID-19 includes lung infection ranging from mild pneumonia to life-threatening acute respiratory distress syndrome (ARDS). Dysregulated host immune response in the lung is a key feature in ARDS pathophysiology. However, cellular actors involved in COVID-19-driven ARDS are poorly understood. Here, in blood and airways of severe COVID-19 patients, we serially analyzed unconventional T cells, a heterogeneous class of T lymphocytes (MAIT, γδT, and iNKT cells) with potent antimicrobial and regulatory functions. Circulating unconventional T cells of COVID-19 patients presented with a profound and persistent phenotypic alteration. In the airways, highly activated unconventional T cells were detected, suggesting a potential contribution in the regulation of local inflammation. Finally, expression of the CD69 activation marker on blood iNKT and MAIT cells of COVID-19 patients on admission was predictive of clinical course and disease severity. Thus, COVID-19 patients present with an altered unconventional T cell biology, and further investigations will be required to precisely assess their functions during SARS-CoV-2-driven ARDS.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/imunologia , Células T Invariáveis Associadas à Mucosa/metabolismo , Células T Matadoras Naturais/metabolismo , Fenótipo , Pneumonia Viral/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Síndrome do Desconforto Respiratório do Adulto/imunologia , Idoso , Antígenos CD/sangue , Antígenos de Diferenciação de Linfócitos T/sangue , Células Cultivadas , Infecções por Coronavirus/virologia , Citocinas/metabolismo , Feminino , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Lectinas Tipo C/sangue , Masculino , Pessoa de Meia-Idade , Células T Invariáveis Associadas à Mucosa/imunologia , Células T Matadoras Naturais/imunologia , Pandemias , Pneumonia Viral/virologia , Prognóstico , Estudos Prospectivos , Síndrome do Desconforto Respiratório do Adulto/virologia , Índice de Gravidade de Doença
14.
Nat Commun ; 11(1): 4471, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901010

RESUMO

A human cell contains hundreds to thousands of mitochondrial DNA (mtDNA) packaged into nucleoids. Currently, the segregation and allocation of nucleoids are thought to be passively determined by mitochondrial fusion and division. Here we provide evidence, using live-cell super-resolution imaging, that nucleoids can be actively transported via KIF5B-driven mitochondrial dynamic tubulation (MDT) activities that predominantly occur at the ER-mitochondria contact sites (EMCS). We further demonstrate that a mitochondrial inner membrane protein complex MICOS links nucleoids to Miro1, a KIF5B receptor on mitochondria, at the EMCS. We show that such active transportation is a mechanism essential for the proper distribution of nucleoids in the peripheral zone of the cell. Together, our work identifies an active transportation mechanism of nucleoids, with EMCS serving as a key platform for the interplay of nucleoids, MICOS, Miro1, and KIF5B to coordinate nucleoids segregation and transportation.


Assuntos
DNA Mitocondrial/metabolismo , Retículo Endoplasmático/metabolismo , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/fisiologia , Animais , Transporte Biológico Ativo , Células COS , Células Cultivadas , Chlorocebus aethiops , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células HEK293 , Humanos , Cinesina/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Camundongos , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Modelos Biológicos , Ratos , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transfecção , Proteínas rho de Ligação ao GTP/metabolismo
15.
Nat Commun ; 11(1): 4278, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32855388

RESUMO

Activation and migration of endogenous mesenchymal stromal cells (MSCs) are critical for bone regeneration. Here, we report a combinational peptide screening strategy for rapid discovery of ligands that not only bind strongly to osteogenic progenitor cells (OPCs) but also stimulate osteogenic cell Akt signaling in those OPCs. Two lead compounds are discovered, YLL3 and YLL8, both of which increase osteoprogenitor osteogenic differentiation in vitro. When given to normal or osteopenic mice, the compounds increase mineral apposition rate, bone formation, bone mass, and bone strength, as well as expedite fracture repair through stimulated endogenous osteogenesis. When covalently conjugated to alendronate, YLLs acquire an additional function resulting in a "tri-functional" compound that: (i) binds to OPCs, (ii) targets bone, and (iii) induces "pro-survival" signal. These bone-targeted, osteogenic peptides are well suited for current tissue-specific therapeutic paradigms to augment the endogenous osteogenic cells for bone regeneration and the treatment of bone loss.


Assuntos
Anabolizantes/farmacologia , Fraturas Ósseas/tratamento farmacológico , Osteogênese/efeitos dos fármacos , Peptídeos/farmacologia , Células-Tronco/efeitos dos fármacos , Anabolizantes/química , Animais , Calcificação Fisiológica/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Fraturas Ósseas/patologia , Humanos , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Orquiectomia , Osteogênese/fisiologia , Ovariectomia , Peptídeos/química , Peptídeos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Técnicas de Síntese em Fase Sólida , Células-Tronco/citologia
16.
Braz J Med Biol Res ; 53(9): e9750, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756815

RESUMO

Our study attempted to compare the efficacies of bone morphogenetic protein (BMP) 2, 6, and 9 in inducing osteogenic differentiation of preodontoblasts (PDBs). We immortalized PDBs by introducing a reversible SV40 T antigen-based immortalization system. Cell proliferation capability was examined by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. The effects of BMP2, 6, and 9 on the osteogenic differentiation of immortalized preodontoblasts (iPDBs) were measured by alkaline phosphatase (ALP) activity assays and alizarin red S staining. The expression of osteogenic markers was evaluated by semiquantitative real-time polymerase chain reaction analysis. To assess ectopic bone formation, rat-derived iPDBs were transfected in culture with adenoviral vectors designated Ad-BMP2, 6, and 9 and subcutaneously or intramuscularly injected into mice. Several BMPs retained endogenous expression in PDBs and regulated the mRNA expression of mineralized tissue-associated proteins. ALP activity and mineralized nodule formation were significantly increased in the Ad-BMP9-transfected group relative to the control group. In addition, the most significant hard tissue formation was in this group. The results indicated that BMP signaling was involved in the osteogenic differentiation of iPDBs. BMP9 could be an efficacious accelerant of the osteogenic differentiation of iPDBs.


Assuntos
Diferenciação Celular , Animais , Proteína Morfogenética Óssea 2 , Proteína Morfogenética Óssea 6 , Proliferação de Células , Células Cultivadas , Regulação da Expressão Gênica , Fator 2 de Diferenciação de Crescimento , Camundongos , Odontoblastos , Osteogênese , Ratos , Transdução de Sinais
17.
Braz J Med Biol Res ; 53(9): e9880, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756816

RESUMO

Rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS) are inflammatory diseases with different bone remodeling patterns. Fibroblast-like synoviocytes (FLS) are cells involved in the transition from an acute and reparable phase to a chronic and persistent stage in these diseases. The distinction of joint phenotypes involves inflammatory cytokines such as tumor necrosis factor alpha (TNF-α), interleukin (IL)-17, and IL-22 directly or through key signaling pathways such as Wnt. To evaluate the role of FLS as the source of Wnt antagonists (sFRP3/FRZB and Dkk1) in the synovia, levels of TNF- α, IL-17, IL-22, Dkk1, and sFRP3 were measured by ELISA directly in the synovial fluid of patients with RA, PsA, or AS. Dkk1 and sFRP3 were also measured in the FLS culture supernatants after different inflammatory stimulus. sFRP3 and Dkk1 are constitutively expressed by FLS. IL-22 and sFRP3 were positively correlated (r=0.76; P<0.01) in synovial fluid. The stimulation of FLS with IL-22, but not TNF-alpha and IL-17, increased the production of sFRP3. No stimulus altered the basal expression of Dkk1. These results showed, for the first time, the ability of IL-22 to increase the expression of sFRP3/FRZB by human FLS in both in vitro and ex vivo models. This finding linked IL-22 to local inhibition of Wnt signaling and possibly to blockade of osteogenesis. Furthermore, FLS presented as a source of this inhibitor in synovial fluid, assigning to this cell a bone injury mechanism.


Assuntos
Interleucinas/metabolismo , Sinoviócitos , Adulto , Células Cultivadas , Feminino , Fibroblastos , Humanos , Masculino , Pessoa de Meia-Idade , Membrana Sinovial , Fator de Necrose Tumoral alfa
18.
Cardiovasc Ther ; 2020: 9397109, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32821285

RESUMO

Chronic systemic inflammation contributes to cardiovascular disease (CVD) and correlates with the abundance of acute phase response (APR) proteins in the liver and plasma. Bromodomain and extraterminal (BET) proteins are epigenetic readers that regulate inflammatory gene transcription. We show that BET inhibition by the small molecule apabetalone reduces APR gene and protein expression in human hepatocytes, mouse models, and plasma from CVD patients. Steady-state expression of serum amyloid P, plasminogen activator inhibitor 1, and ceruloplasmin, APR proteins linked to CVD risk, is reduced by apabetalone in cultured hepatocytes and in humanized mouse liver. In cytokine-stimulated hepatocytes, apabetalone reduces the expression of C-reactive protein (CRP), alpha-2-macroglobulin, and serum amyloid P. The latter two are also reduced by apabetalone in the liver of endotoxemic mice. BET knockdown in vitro also counters cytokine-mediated induction of the CRP gene. Mechanistically, apabetalone reduces the cytokine-driven increase in BRD4 BET occupancy at the CRP promoter, confirming that transcription of CRP is BET-dependent. In patients with stable coronary disease, plasma APR proteins CRP, IL-1 receptor antagonist, and fibrinogen γ decrease after apabetalone treatment versus placebo, resulting in a predicted downregulation of the APR pathway and cytokine targets. We conclude that CRP and components of the APR pathway are regulated by BET proteins and that apabetalone counters chronic cytokine signaling in patients.


Assuntos
Anti-Inflamatórios/farmacologia , Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Citocinas/metabolismo , Endotoxemia/tratamento farmacológico , Epigênese Genética/efeitos dos fármacos , Proteínas Nucleares/metabolismo , Quinazolinonas/farmacologia , Fatores de Transcrição/metabolismo , Animais , Sítios de Ligação , Proteína C-Reativa/genética , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Células Cultivadas , Ceruloplasmina/genética , Ceruloplasmina/metabolismo , Citocinas/genética , Modelos Animais de Doenças , Endotoxemia/genética , Endotoxemia/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Proteínas Nucleares/genética , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Regiões Promotoras Genéticas , Componente Amiloide P Sérico/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , alfa-Macroglobulinas/genética , alfa-Macroglobulinas/metabolismo
19.
Int J Oral Sci ; 12(1): 22, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737282

RESUMO

A splicing mutation in VPS4B can cause dentin dysplasia type I (DD-I), a hereditary autosomal-dominant disorder characterized by rootless teeth, the etiology of which is genetically heterogeneous. In our study, dental follicle cells (DFCs) were isolated and cultured from a patient with DD-I and compared with those from an age-matched, healthy control. In a previous study, this DD-I patient was confirmed to have a loss-of-function splicing mutation in VPS4B (IVS7 + 46C > G). The results from this study showed that the isolated DFCs were vimentin-positive and CK14-negative, indicating that the isolated cells were derived from the mesenchyme. DFCs harboring the VPS4B mutation had a significantly higher proliferation rate from day 3 to day 8 than control DFCs, indicating that VPS4B is involved in cell proliferation. The cells were then replenished with osteogenic medium to investigate how the VPS4B mutation affected osteogenic differentiation. Induction of osteogenesis, detected by alizarin red and alkaline phosphatase staining in vitro, was decreased in the DFCs from the DD-I patient compared to the control DFCs. Furthermore, we also found that the VPS4B mutation in the DD-I patient downregulated the expression of osteoblast-related genes, such as ALP, BSP, OCN, RUNX2, and their encoded proteins. These outcomes confirmed that the DD-I-associated VPS4B mutation could decrease the capacity of DFCs to differentiate during the mineralization process and may also impair physiological root formation and bone remodeling. This might provide valuable insights and implications for exploring the pathological mechanisms underlying DD-I root development.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/genética , Saco Dentário/citologia , Displasia da Dentina/genética , Displasia da Dentina/fisiopatologia , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Osteogênese/genética , Processamento de RNA/genética , Estudos de Casos e Controles , Diferenciação Celular/genética , Células Cultivadas , Displasia da Dentina/patologia , Humanos , Mutação/genética
20.
Sheng Wu Gong Cheng Xue Bao ; 36(7): 1431-1439, 2020 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-32748601

RESUMO

The purpose of this study is to provide a culture for mouse bone marrow-derived macrophages (BMDM) and peritoneal macrophages (PM) and to characterize their molecular and cellular biology. The cell number and purity from the primary culture were assessed by cell counter and flow cytometry, respectively. Morphological features were evaluated by inverted microscope. Phagocytosis by macrophages was detected by the neutral red dye uptake assay. Phenotypic markers were analyzed by real-time fluorescent quantitative PCR. Our results show that the cell number was much higher from culture of BMDM than PM, while there was no significant difference regarding the percentage of F4/80+CD11b+ cells (98.30%±0.53% vs. 94.83%±1.42%; P>0.05). The proliferation rate of BMDM was significantly higher than PM in the presence of L929 cell conditioned medium, by using CCK-8 assay. However, PM appeared to adhere to the flask wall and extend earlier than BMDM. The phagocytosis capability of un-stimulated BMDM was significantly higher than PM, as well as lipopolysaccharide (LPS)-stimulated BMDM, except the BMDM stimulated by low dose LPS (0.1 µg/mL). Furthermore, Tnfα expression was significantly higher in un-stimulated BMDM than PM, while Arg1 and Ym1 mRNA expression were significantly lower than PM. The expression difference was persistent if stimulated by LPS+IFN-γ or IL-4. Our data indicate that bone marrow can get larger amounts of macrophages than peritoneal cavity. However, it should be aware that the molecular and cellular characteristics were different between these two culture systems.


Assuntos
Células da Medula Óssea , Macrófagos , Fagocitose , Animais , Células da Medula Óssea/fisiologia , Células Cultivadas , Meios de Cultivo Condicionados , Lipopolissacarídeos/metabolismo , Macrófagos/classificação , Macrófagos/fisiologia , Camundongos
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