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1.
Cartilage ; : 19476035241247700, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38726681

RESUMO

OBJECTIVE: To investigate the effect of higher cumulative defined daily dose per year (cDDD/y) compared with lower cDDD/y of statin use in the incidence of any joint osteoarthritis (OA). DESIGN: In this population-based retrospective cohort study, patients who were aged ≥40 years were newly initiated on statin therapy between 2002 and 2011, and had a statin prescription for ≥90 days in the first year of treatment were identified from the 2000 Longitudinal Generation Tracking Database. All patients were separated into groups with higher cDDD/y (>120 cDDD/y) and lower cDDD/y (≤120 cDDD/y; as an active comparator) values. Propensity score matching was performed to balance potential confounders. All recruited patients were followed up for 8 years. Marginal Cox proportional hazard models were used to estimate time-to-event outcomes of OA. RESULTS: Compared with lower cDDD/y use, higher cDDD/y use did not reduce the risk of any joint OA (adjusted hazard ratio, 1.07; 95% confidence interval, 0.99-1.14). Dose-related analysis did not reveal any dose-dependent association. A series of sensitivity analyses showed similar results. Joint-specific analyses revealed that statin did not reduce the incidence of knee, hand, hip, and weight-bearing (knee or hip) OA. CONCLUSIONS: Higher cDDD/y statin use did not reduce the risk of OA in this Taiwanese nationwide cohort study. The complexity of OA pathogenesis might contribute to the ineffectiveness of statin. Repurposing statin with its anti-inflammation properties might be ineffective for OA development, and balancing the catabolism and anabolism of cartilage might be a major strategy for OA prevention.

2.
Int J Mol Sci ; 25(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38542074

RESUMO

Lethal toxin (LT) is the critical virulence factor of Bacillus anthracis, the causative agent of anthrax. One common symptom observed in patients with anthrax is thrombocytopenia, which has also been observed in mice injected with LT. Our previous study demonstrated that LT induces thrombocytopenia by suppressing megakaryopoiesis, but the precise molecular mechanisms behind this phenomenon remain unknown. In this study, we utilized 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced megakaryocytic differentiation in human erythroleukemia (HEL) cells to identify genes involved in LT-induced megakaryocytic suppression. Through cDNA microarray analysis, we identified Dachshund homolog 1 (DACH1) as a gene that was upregulated upon TPA treatment but downregulated in the presence of TPA and LT, purified from the culture supernatants of B. anthracis. To investigate the function of DACH1 in megakaryocytic differentiation, we employed short hairpin RNA technology to knock down DACH1 expression in HEL cells and assessed its effect on differentiation. Our data revealed that the knockdown of DACH1 expression suppressed megakaryocytic differentiation, particularly in polyploidization. We demonstrated that one mechanism by which B. anthracis LT induces suppression of polyploidization in HEL cells is through the cleavage of MEK1/2. This cleavage results in the downregulation of the ERK signaling pathway, thereby suppressing DACH1 gene expression and inhibiting polyploidization. Additionally, we found that known megakaryopoiesis-related genes, such as FOSB, ZFP36L1, RUNX1, FLI1, AHR, and GFI1B genes may be positively regulated by DACH1. Furthermore, we observed an upregulation of DACH1 during in vitro differentiation of CD34-megakaryocytes and downregulation of DACH1 in patients with thrombocytopenia. In summary, our findings shed light on one of the molecular mechanisms behind LT-induced thrombocytopenia and unveil a previously unknown role for DACH1 in megakaryopoiesis.


Assuntos
Antraz , Bacillus anthracis , Leucemia Eritroblástica Aguda , Trombocitopenia , Animais , Humanos , Camundongos , Antígenos de Bactérias/metabolismo , Bacillus anthracis/metabolismo , Fator 1 de Resposta a Butirato/metabolismo , Diferenciação Celular , Trombocitopenia/induzido quimicamente , Trombocitopenia/genética
3.
Diagnostics (Basel) ; 14(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38472940

RESUMO

Bladder cancer (BCa) is a significant health issue and poses a healthcare burden on patients, highlighting the importance of an effective detection method. Here, we developed a urine DNA methylation diagnostic panel for distinguishing between BCa and non-BCa. In the discovery stage, an analysis of the TCGA database was conducted to identify BCa-specific DNA hypermethylation markers. In the validation phase, DNA methylation levels of urine samples were measured with real-time quantitative methylation-specific PCR (qMSP). Comparative analysis of the methylation levels between BCa and non-BCa, along with the receiver operating characteristic (ROC) analyses with machine learning algorithms (logistic regression and decision tree methods) were conducted to develop practical diagnostic panels. The performance evaluation of the panel shows that the individual biomarkers of ZNF671, OTX1, and IRF8 achieved AUCs of 0.86, 0.82, and 0.81, respectively, while the combined yielded an AUC of 0.91. The diagnostic panel using the decision tree algorithm attained an accuracy, sensitivity, and specificity of 82.6%, 75.0%, and 90.9%, respectively. Our results show that the urine-based DNA methylation diagnostic panel provides a sensitive and specific method for detecting and stratifying BCa, showing promise as a standard test that could enhance the diagnosis and prognosis of BCa in clinical settings.

4.
Stem Cell Res Ther ; 14(1): 300, 2023 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-37864264

RESUMO

BACKGROUND: Granulocyte colony-stimulating factor (G-CSF)-mediated mobilization of hematopoietic stem cells (HSCs) is a well-established method to prepare HSCs for transplantation nowadays. A sufficient number of HSCs is critical for successful HSC transplantation. However, approximately 2-6% of healthy stem cell donors are G-CSF-poor mobilizers for unknown reasons; thus increasing the uncertainties of HSC transplantation. The mechanism underlining G-CSF-mediated HSC mobilization remains elusive, so detailed mechanisms and an enhanced HSC mobilization strategy are urgently needed. Evidence suggests that P-selectin and P-selectin glycoprotein ligand-1 (PSGL-1) are one of the cell-cell adhesion ligand-receptor pairs for HSCs to keep contacting bone marrow (BM) stromal cells before being mobilized into circulation. This study hypothesized that blockage of PSGL-1 and P-selectin may disrupt HSC-stromal cell interaction and facilitate HSC mobilization. METHODS: The plasma levels of soluble P-selectin (sP-sel) before and after G-CSF administration in humans and male C57BL/6J mice were analyzed using enzyme-linked immunosorbent assay. Male mice with P-selectin deficiency (Selp-/-) were further employed to investigate whether P-selectin is essential for G-CSF-induced HSC mobilization and determine which cell lineage is sP-sel derived from. Finally, wild-type mice were injected with either G-CSF or recombinant sP-sel to investigate whether sP-sel alone is sufficient for inducing HSC mobilization and whether it accomplishes this by binding to HSCs and disrupting their interaction with stromal cells in the BM. RESULTS: A significant increase in plasma sP-sel levels was observed in humans and mice following G-CSF administration. Treatments of G-CSF induced a decrease in the level of HSC mobilization in Selp-/- mice compared with the wild-type (Selp+/+) controls. Additionally, the transfer of platelets derived from wild-type mice can ameliorate the defected HSC mobilization in the Selp-/- recipients. G-CSF induces the release of sP-sel from platelets, which is sufficient to mobilize BM HSCs into the circulation of mice by disrupting the PSGL-1 and P-selectin interaction between HSCs and stromal cells. These results collectively suggested that P-selectin is a critical factor for G-CSF-induced HSC mobilization. CONCLUSIONS: sP-sel was identified as a novel endogenous HSC-mobilizing agent. sP-sel injections achieved a relatively faster and more convenient regimen to mobilize HSCs in mice than G-CSF. These findings may serve as a reference for developing and optimizing human HSC mobilization in the future.


Assuntos
Mobilização de Células-Tronco Hematopoéticas , Selectina-P , Masculino , Camundongos , Humanos , Animais , Mobilização de Células-Tronco Hematopoéticas/métodos , Selectina-P/genética , Selectina-P/metabolismo , Camundongos Endogâmicos C57BL , Células-Tronco Hematopoéticas/metabolismo , Fator Estimulador de Colônias de Granulócitos/farmacologia , Fator Estimulador de Colônias de Granulócitos/metabolismo , Proteínas Recombinantes/farmacologia
5.
J Periodontol ; 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37793052

RESUMO

BACKGROUND: The lipid-lowering and anti-inflammatory effects of statins and fibrates may ameliorate periodontitis. Patients with hyperlipidemia tend to have a worse periodontal status. This study assessed the association between the use of statins/fibrates and the incidence of chronic periodontitis in patients with hyperlipidemia in Taiwan. METHODS: This retrospective cohort study enrolled patients newly diagnosed with hyperlipidemia between 2001 and 2012 from the 2000 Longitudinal Generation Tracking Database and followed them for 5 years. The study population was divided into four groups: statin monotherapy, fibrate monotherapy, combination therapy (both statins and fibrates), and control (neither statins nor fibrates). Each patient in the treatment group was matched at a ratio of 1:1 with a control. Chronic periodontitis risk was compared in the three study arms by using a Cox proportional hazard model. RESULTS: Chronic periodontitis risk was reduced by 25.7% in the combination therapy group compared with the control group (adjusted hazard ratio [aHR], 0.743; 95% confidence interval (CI), 0.678-0.815). Low dose (<360 cumulative defined daily dose [cDDD]) and shorter duration (<2 years) of statin monotherapy seem to be associated with an increased risk of chronic periodontitis; high dose (≥720 cDDD/≥1080 cDDD) and longer duration (≥3 years) of statin/fibrate monotherapy may be correlated with a lower risk of periodontitis. Hydrophobic statin users had a lower chronic periodontitis risk than hydrophilic statin users. CONCLUSION: Chronic periodontitis risk was lower in patients with hyperlipidemia on combination treatment with statins and fibrates, and the risk decreased when patients used statins or fibrates for >3 years.

6.
Sci Rep ; 13(1): 7399, 2023 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-37149698

RESUMO

Recent experimental and observational research has suggested that childhood allergic asthma and other conditions may be the result of prenatal exposure to environmental contaminants, such as di-(2-ethylhexyl) phthalate (DEHP). In a previous epidemiological study, we found that ancestral exposure (F0 generation) to endocrine disruptors or the common plasticizer DEHP promoted allergic airway inflammation via transgenerational transmission in mice from generation F1 to F4. In the current study, we employed a MethylationEPIC Beadchip microarray to examine global DNA methylation in the human placenta as a function of maternal exposure to DEHP during pregnancy. Interestingly, global DNA hypomethylation was observed in placental DNA following exposure to DEHP at high concentrations. Bioinformatic analysis confirmed that DNA methylation affected genes related to neurological disorders, such as autism and dementia. These results suggest that maternal exposure to DEHP may predispose offspring to neurological diseases. Given the small sample size in this study, the potential role of DNA methylation as a biomarker to assess the risk of these diseases deserves further investigation.


Assuntos
Asma , Dietilexilftalato , Disruptores Endócrinos , Doenças do Sistema Nervoso , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Animais , Feminino , Camundongos , Humanos , Criança , Dietilexilftalato/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/genética , Placenta , Exposição Materna/efeitos adversos , Epigênese Genética , Asma/induzido quimicamente , Asma/epidemiologia , Doenças do Sistema Nervoso/induzido quimicamente , Doenças do Sistema Nervoso/genética
7.
Front Pharmacol ; 14: 1096999, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36873987

RESUMO

Objective: To investigate the association between statin use and risk of gout in patients with hyperlipidemia. Methods: In this population-based retrospective cohort study, patients ≥20 years and diagnosed as having incident hyperlipidemia between 2001 and 2012 were identified from the 2000 Longitudinal Generation Tracking Database in Taiwan. Regular statin users (incident statin use, having 2 times and ≥90 days of prescription for the first year) and two active comparators [irregular statin use and other lipid-lowering agent (OLLA) use] were compared; the patients were followed up until the end of 2017. Propensity score matching was applied to balance potential confounders. Time-to-event outcomes of gout and dose- and duration-related associations were estimated using marginal Cox proportional hazard models. Results: Regular statin use non-significantly reduced gout risk compared with irregular statin use (aHR, 0.95; 95% CI, 0.90-1.01) and OLLA use (aHR, 0.94; 95% CI, 0.84-1.04). However, a protective effect was noted for a cumulative defined daily dose (cDDD) of >720 (aHR, 0.57; 95% CI, 0.47-0.69 compared with irregular statin use and aHR, 0.48; 95% CI, 0.34-0.67 compared with OLLA use) or a therapy duration of >3 years (aHR, 0.76; 95% CI, 0.64-0.90 compared with irregular statin use and aHR, 0.50; 95% CI, 0.37-0.68 compared with OLLA use). Dose- and duration-dependent associations were consistent in the 5-year sensitivity analyses. Conclusion: Although statin use was not associated with a reduction in gout risk, the protective benefit was observed in those receiving higher cumulative doses or with a longer therapy duration.

8.
Oncol Lett ; 23(4): 117, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35261631

RESUMO

Breast cancer is among the most frequently diagnosed cancer types and the leading cause of cancer-related death in women. The mortality rate of patients with breast cancer is currently increasing, perhaps due to a lack of early screening tools. In the present study, using The Cancer Genome Atlas (TCGA) breast cancer dataset (n=883), it was determined that methylation of the protocadherin ß15 (PCDHB15) promoter was higher in breast cancer samples than that in normal tissues. A negative association between promoter methylation and expression of PCDHB15 was observed in the TCGA dataset and breast cancer cell lines. In TCGA cohort, lower PCDHB15 expression was associated with shorter relapse-free survival times. Treatment with the DNA methyltransferase inhibitor restored PCDHB15 expression in a breast cancer cell line; however, overexpression of PCDHB15 was shown to suppress colony formation. PCDHB15 methylation detected in circulating cell-free DNA (cfDNA) isolated from serum samples was higher in patients with breast cancer (40.8%) compared with that in patients with benign tumors (22.4%). PCDHB15 methylation was not correlated with any clinical parameters. Taken together, PCDHB15 is a potential tumor suppressor in cases of breast cancer, which can be epigenetically silenced via promoter methylation. PCDHB15 methylation using cfDNA is a novel minimally invasive epigenetic biomarker for the diagnosis and prognosis of breast cancer.

9.
Epigenomes ; 5(2)2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-34968298

RESUMO

Cancer immunotherapy using monoclonal antibodies targeting immune checkpoint proteins, such as PD-L1 or PD-1 (i [...].

10.
Stem Cell Res Ther ; 12(1): 274, 2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33957977

RESUMO

BACKGROUND: Hematopoiesis occurs in the bone marrow, producing a complete spectrum of blood cells to maintain homeostasis. In addition to light microscopy, chromosome analysis, and polymerase chain reaction, flow cytometry is a feasible and fast method for quantitatively analyzing hematological diseases. However, because sufficient specific cell markers are scarce, dyserythropoietic diseases are challenging to identify through flow cytometry. METHODS: Bone marrow samples from C57BL/B6 mice and one healthy donor were analyzed using traditional two-marker (CD71 and glycophorin A) flow cytometry analysis. After cell sorting, the gene expressions of membrane proteins in early and late erythropoiesis precursors and in nonerythroid cells were characterized using microarray analysis. RESULTS: Among characterized gene candidates, aquaporin 0 (AQP0) expressed as a surface protein in early- and late-stage erythropoiesis precursors and was not expressed on nonerythroid cells. With the help of AQP0 staining, we could define up to five stages of erythropoiesis in both mouse and human bone marrow using flow cytometry. In addition, because patients with dyserythropoiesis generally exhibited a reduced population of APQ0high cells relative to healthy participants, the analysis results also suggested that the levels of APQ0high cells in early erythropoiesis serve as a novel biomarker that distinguishes normal from dysregulated erythropoiesis. CONCLUSIONS: AQP0 was successfully demonstrated to be a marker of erythroid differentiation. The expression levels of AQP0 are downregulated in patients with dyserythropoiesis, indicating a critical role of AQP0 in erythropoiesis. Accordingly, the level of AQP0high in early erythroid precursor cells may serve as a reference parameter for diagnosing diseases associated with dyserythropoiesis.


Assuntos
Eritropoese , Doenças Hematológicas , Animais , Aquaporinas , Biomarcadores , Células da Medula Óssea , Eritropoese/genética , Proteínas do Olho , Humanos , Camundongos , Camundongos Endogâmicos C57BL
11.
Front Immunol ; 12: 616394, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33995345

RESUMO

In tropical and subtropical regions, mosquito-borne dengue virus (DENV) infections can lead to severe dengue, also known as dengue hemorrhage fever, which causes bleeding, thrombocytopenia, and blood plasma leakage and increases mortality. Although DENV-induced platelet cell death was linked to disease severity, the role of responsible viral factors and the elicitation mechanism of abnormal platelet activation and cell death remain unclear. DENV and virion-surface envelope protein domain III (EIII), a cellular binding moiety of the virus particle, highly increase during the viremia stage. Our previous report suggested that exposure to such viremia EIII levels can lead to cell death of endothelial cells, neutrophils, and megakaryocytes. Here we found that both DENV and EIII could induce abnormal platelet activation and predominantly necrotic cell death pyroptosis. Blockages of EIII-induced platelet signaling using the competitive inhibitor chondroitin sulfate B or selective Nlrp3 inflammasome inhibitors OLT1177 and Z-WHED-FMK markedly ameliorated DENV- and EIII-induced thrombocytopenia, platelet activation, and cell death. These results suggest that EIII could be considered as a virulence factor of DENV, and that Nlrp3 inflammasome is a feasible target for developing therapeutic approaches against dengue-induced platelet defects.


Assuntos
Plaquetas/metabolismo , Vírus da Dengue/fisiologia , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Dengue Grave/complicações , Trombocitopenia/etiologia , Trombocitopenia/metabolismo , Animais , Biomarcadores , Coagulação Sanguínea , Testes de Coagulação Sanguínea , Plaquetas/imunologia , Morte Celular , Modelos Animais de Doenças , Suscetibilidade a Doenças , Metabolismo Energético , Imunofenotipagem , Camundongos , Camundongos Knockout , Mitocôndrias/metabolismo , Ativação Plaquetária , Domínios e Motivos de Interação entre Proteínas/imunologia , Dengue Grave/virologia , Trombocitopenia/sangue , Trombocitopenia/diagnóstico , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/metabolismo
12.
Cancer Cell Int ; 21(1): 226, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33874979

RESUMO

BACKGROUND: Urothelial carcinoma (UC) is the second most common malignancy of the urinary system with high rate of recurrence, UC patients therefore needed to be treated with surgery followed by chemotherapy. Development of novel therapeutics with minimal side-effect is an urgent issue. Our previous study showed that cyproheptadine (CPH), an anti-histamine, exhibited antitumor activity in UC in vitro and in an xenograft model. However, the molecular mechanism of how CPH inhibits tumor progression is not fully understood. METHODS: Genes that were upregulated after treatment with CPH in UC cells, were examined by RNA-Seq. Real-time quantitative PCR (RT-qPCR) was employed to detect IRF6 expression while COBRA assay and bisulphite pyrosequencing were used to examine promoter methylation of IRF6. Enrichment of total H3K27 acetylation and H3K4 mono-methylation were detected by western blotting. Colony formation and flow cytometry were used to examine proliferation and apoptosis in UC cells overexpressed or depleted with IRF6. Nude mice xenograft model was used to examine the effect of IRF6 in UC. RESULTS: Our result showed that several genes, including IRF6 were upregulated after treatment with CPH in BFTC905 UC cells. Further experiments found that treatment of CPH could restore the expression of IRF6 in several other UC cell lines, probably due to promoter hypomethylation and enrichment of H3K27 acetylation and H3K4 mono-methylation. These results may be due to the fact that CPH could alter the activity, but not the expression of epigenetic modifiers. Finally, re-expression of IRF6 in UC inhibited tumor growth in vitro and in an xenograft mouse model, by inducing apoptosis. CONCLUSION: In conclusion, our results suggested that CPH may be an epigenetic modifier, modulating the expression of the potential tumor suppressor IRF6, in inhibiting tumor growth in UC.

13.
Front Oncol ; 11: 575667, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33718136

RESUMO

PURPOSE: The purpose of this study was to identify genes that were epigenetically silenced by STAT3 in gastric cancer. METHODS: MBDcap-Seq and expression microarray were performed to identify genes that were epigenetically silenced in AGS gastric cancer cell lines depleted of STAT3. Cell lines and animal experiments were performed to investigate proliferation and metastasis of miR-193a and YWHAZ in gastric cancer cell lines. Bisulfite pyrosequencing and tissue microarray were performed to investigate the promoter methylation of miR-193a and expression of STAT3, YWHAZ in patients with gastritis (n = 8) and gastric cancer (n = 71). Quantitative methylation-specific PCR was performed to examine miR-193a promoter methylation in cell-free DNA of serum samples in gastric cancer patients (n = 19). RESULTS: As compared with parental cells, depletion of STAT3 resulted in demethylation of a putative STAT3 target, miR-193a, in AGS gastric cancer cells. Although bisulfite pyrosequencing and epigenetic treatment confirmed that miR-193a was epigenetically silenced in gastric cancer cell lines, ChIP-PCR found that it may be indirectly affected by STAT3. Ectopic expression of miR-193a in AGS cells inhibited proliferation and migration of gastric cancer cells. Further expression microarray and bioinformatics analysis identified YWHAZ as one of the target of miR-193a in AGS gastric cancer cells, such that depletion of YWHAZ reduced migration in AGS cells, while its overexpression increased invasion in MKN45 cells in vitro and in vivo. Clinically, bisulfite pyrosequencing revealed that promoter methylation of miR-193a was significantly higher in human gastric cancer tissues (n = 11) as compared to gastritis (n = 8, p < 0.05). Patients infected with H. pylori showed a significantly higher miR-193a methylation than those without H. pylori infection (p < 0.05). Tissue microarray also showed a positive trend between STAT3 and YWHAZ expression in gastric cancer patients (n = 60). Patients with serum miR-193a methylation was associated with shorter overall survival than those without methylation (p < 0.05). CONCLUSIONS: Constitutive activation of JAK/STAT signaling may confer epigenetic silencing of the STAT3 indirect target and tumor suppressor microRNA, miR-193a in gastric cancer. Transcriptional suppression of miR-193a may led to overexpression of YWHAZ resulting in tumor progression. Targeted inhibition of STAT3 may be a novel therapeutic strategy against gastric cancer.

14.
Cell Mol Immunol ; 18(5): 1341-1342, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33139906
15.
Stem Cell Res Ther ; 9(1): 119, 2018 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-29720275

RESUMO

BACKGROUND: Red blood cells are the most abundant cells in the blood that deliver oxygen to the whole body. Erythropoietin (EPO), a positive regulator of erythropoiesis, is currently the major treatment for chronic anemia. Granulocyte colony-stimulating factor (G-CSF) is a multifunctional cytokine and a well-known regulator of hematopoietic stem cell proliferation, differentiation, and mobilization. The use of EPO in combination with G-CSF has been reported to synergistically improve erythroid responses in a group of patients with myelodysplastic syndromes who did not respond to EPO treatment alone; however, the mechanism remains unclear. METHODS: C57BL/6 J mice injected with G-CSF or EPO were used to compare the erythropoiesis status and the efficiency of erythroid mobilization by flow cytometry. RESULTS: In this study, we found that G-CSF induced more orthochromatophilic erythroblast production than did EPO in the bone marrow and spleen. In addition, in contrast to EPO treatments, G-CSF treatments enhanced the efficiency of the mobilization of newly synthesized reticulocytes into peripheral blood. Our results demonstrated that the effects of G-CSF on erythropoiesis and erythrocytic mobilization were independent of EPO secretion and, in contrast to EPO, G-CSF promoted progression of erythropoiesis through transition of early stage R2 (basophilic erythroblasts) to late stage R4 (orthochromatophilic erythroblasts). CONCLUSIONS: We demonstrate for the first time that G-CSF treatments induce a faster erythropoiesis-enhancing response than that of EPO. These findings suggest an alternative approach to treating acute anemia, especially when patients are experiencing a clinical emergency in remote areas without proper blood bank supplies.


Assuntos
Eritropoese/efeitos dos fármacos , Eritropoetina/uso terapêutico , Animais , Eritropoetina/farmacologia , Fator Estimulador de Colônias de Granulócitos/farmacologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
16.
Virulence ; 8(8): 1719-1731, 2017 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-28622093

RESUMO

Dengue virus (DENV) infection can cause severe, life-threatening events, and no specific treatments of DENV infection are currently approved. Although thrombocytopenia is frequently observed in dengue patients, its pathogenesis is still not fully understood. Previous studies have suggested that DENV-induced thrombocytopenia occurs through viral-replication-mediated megakaryopoiesis inhibition in the bone marrow; however, the exact mechanism for megakaryopoiesis suppression remains elusive. In this study, a reductionist approach was applied, in which C57B/6J mice were inoculated with recombinant DENV-envelope protein domain III (DENV-EIII) instead of the full viral particle. Our results demonstrated that DENV-EIII-suppressed megakaryopoiesis is similar to those observed with DENV infection. Furthermore, in agreement with our in vivo analyses, DENV-EIII sufficiently suppressed the megakaryopoiesis of progenitor cells from murine bone marrow and human cord blood in vitro. Additional analyses suggested that autophagy impairment and apoptosis are involved in DENV-EIII-mediated suppression of megakaryopoiesis. These data suggest that, even without viral replication, the binding of DENV-EIII to the cell surface is sufficient to suppress megakaryopoiesis.


Assuntos
Vírus da Dengue/metabolismo , Dengue/fisiopatologia , Trombopoese , Proteínas do Envelope Viral/metabolismo , Animais , Autofagia , Linhagem Celular , Dengue/virologia , Vírus da Dengue/química , Vírus da Dengue/genética , Interações Hospedeiro-Patógeno , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Envelope Viral/genética
17.
Exp Cell Res ; 339(1): 44-50, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26439194

RESUMO

Established from the calvaria of newborn macrophage colony-stimulating factor (M-CSF)-deficient mice, OP9 is a stromal cell line that used as a feeder layer to support the in vitro differentiation of pluripotent stem cells into various hematopoietic lineage cells, including granulocytes, erythrocytes, lymphocytes, and megakaryocytes. However, as a primary culture cell line, OP9 can be used as stromal cells for only 1 month. Therefore, to obtain functional OP9 cells, numerous M-CSF-deficient newborn mice must be sacrificed. These limitations in some ways restrict the application of OP9 cells in longterm and largescale experiments. In this study, we used human papillomavirus 16 E6 and E7 genes to generate immortalized OP9 stromal cells, designated I-OP9 cells, and then tested their ability to support the megakaryocytic differentiation of pluripotent stem cells in vitro. I-OP9 cells have similar morphology and properties as do parental OP9 cells, and, as expected, have an extended lifespan and can support megakaryocytic differentiation. Our data suggest that the method used in this study, including establishing I-OP9 cells, enables the possibility to enlarge and lengthen the scale of the experiment and, more critically, provides a humanistic approach for preparing stromal cells that support the hematopoietic differentiation of pluripotent stem cells in vitro.


Assuntos
Diferenciação Celular , Transformação Celular Neoplásica/patologia , Técnicas de Cocultura , Embrião de Mamíferos/citologia , Megacariócitos/citologia , Células-Tronco Embrionárias Murinas/citologia , Células Estromais/citologia , Animais , Transformação Celular Neoplásica/metabolismo , Células Cultivadas , Embrião de Mamíferos/metabolismo , Citometria de Fluxo , Imunofluorescência , Hematopoese , Humanos , Fator Estimulador de Colônias de Macrófagos/fisiologia , Masculino , Megacariócitos/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Células-Tronco Embrionárias Murinas/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Estromais/metabolismo
18.
Molecules ; 20(4): 6520-32, 2015 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-25871371

RESUMO

Some new sydnonyl-substituted thiazolidine derivatives were synthesized in high yields by the modified Knoevenagel condensation of 3-aryl-4-formylsydnones with thiazolidine-2,4-dione and 2-thioxo-thiazolidine-4-one, respectively. All the synthesized thiazolidine derivatives were screened by paper-disc method to identify their antimicrobial activities against three bacteria viz. Staphylococcus aureus, Proteus vulgaris and Escherichia coli, and two fungal cultures viz. Aspergillus niger and Penicillium citrinum. The reference drugs were Norfloxacin and Griseofulvin, respectively. The screening data indicated that the tested sydnonyl-substituted thiazolidine derivatives exhibited no obvious antibacterial activity compared with the standard drug Norfloxacin. However, thiazolidine derivatives displayed significant antifungal activities against Penicillium citrinum and Aspergillus niger. Notably, all of the tested compounds showed growth inhibitory activity 1.5-4.4 times higher than that of the standard drug Griseofulvin against the two fungi.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Tiazolidinas/química , Tiazolidinas/farmacologia , Anti-Infecciosos/síntese química , Bactérias/efeitos dos fármacos , Técnicas de Química Sintética , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Sidnonas/química , Tiazolidinas/síntese química
19.
PLoS One ; 9(11): e111149, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25384016

RESUMO

Anthrax lethal toxin (LT), one of the primary virulence factors of Bacillus anthracis, causes anthrax-like symptoms and death in animals. Experiments have indicated that levels of erythrocytopenia and hypoxic stress are associated with disease severity after administering LT. In this study, the granulocyte colony-stimulating factor (G-CSF) was used as a therapeutic agent to ameliorate anthrax-LT- and spore-induced mortality in C57BL/6J mice. We demonstrated that G-CSF promoted the mobilization of mature erythrocytes to peripheral blood, resulting in a significantly faster recovery from erythrocytopenia. In addition, combined treatment using G-CSF and erythropoietin tended to ameliorate B. anthracis-spore-elicited mortality in mice. Although specific treatments against LT-mediated pathogenesis remain elusive, these results may be useful in developing feasible strategies to treat anthrax.


Assuntos
Antígenos de Bactérias/toxicidade , Toxinas Bacterianas/toxicidade , Eritrócitos/efeitos dos fármacos , Eritropoetina/farmacologia , Fator Estimulador de Colônias de Granulócitos/farmacologia , Análise de Variância , Animais , Antígenos de Bactérias/intoxicação , Toxinas Bacterianas/intoxicação , Eritrócitos/fisiologia , Células Precursoras Eritroides , Eritropoese/efeitos dos fármacos , Eritropoese/fisiologia , Citometria de Fluxo , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Estimativa de Kaplan-Meier , Camundongos , Camundongos Endogâmicos C57BL
20.
J Virol Methods ; 201: 1-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24530430

RESUMO

Emerging life threatening pathogens such as severe acute aspiratory syndrome-coronavirus (SARS-CoV), avian-origin influenzas H7N9, and the Middle East respiratory syndrome coronavirus (MERS-CoV) have caused a high case-fatality rate and psychological effects on society and the economy. Therefore, a simple, rapid, and safe method to investigate a therapeutic approach against these pathogens is required. In this study, a simple, quick, and safe cell adhesion inhibition assay was developed to determine the potential cellular binding site on the SARS-CoV spike protein. Various synthetic peptides covering the potential binding site helped to minimize further the binding motif to 10-25 residues. Following analyses, 2 peptides spanning the 436-445 and 437-461 amino acids of the spike protein were identified as peptide inhibitor or peptide vaccine candidates against SARS-CoV.


Assuntos
Adesão Celular , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/fisiologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Ligação Viral , Animais , Antivirais/isolamento & purificação , Sítios de Ligação , Linhagem Celular , Humanos , Peptídeos/isolamento & purificação , Ligação Proteica
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