RESUMO
Severe acquired aplastic anaemia (AA) is a serious disease characterised by autoreactive T cells attacking haematopoietic stem cells, leading to marrow hypoplasia and pancytopenia. Immunosuppressive therapy combined with antithymocyte globulin and ciclosporin can rescue most patients with AA. However, the relapse after ciclosporin withdrawal and the severe side effects of long-term ciclosporin administration remain unresolved. As such, new strategies should be developed to supplement current therapeutics and treat AA. In this study, the possibility of all-trans-retinoic acid (ATRA) as an alternative AA treatment was tested by using an immune-mediated mouse model of AA. Results revealed that ATRA inhibited T-cell proliferation, activation and effector function. It also restrained the Fas/Fasl pathway, shifted Th1 towards Th2 cell development, rebalanced T-cell subsets at a relatively high level and corrected the Th1/Th2 ratio by targeting NFAT1 signalling. In addition, ATRA inhibited Th17 cell differentiation and promoted regulatory T-cell development. Therefore, ATRA was an effective agent to improve AA treatment outcomes.
Assuntos
Anemia Aplástica/imunologia , Diferenciação Celular/efeitos dos fármacos , Fatores de Transcrição NFATC/imunologia , Transdução de Sinais/imunologia , Células Th1/imunologia , Células Th2/imunologia , Tretinoína/farmacologia , Anemia Aplástica/patologia , Animais , Diferenciação Celular/imunologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Transdução de Sinais/efeitos dos fármacos , Células Th1/patologia , Células Th17/imunologia , Células Th17/patologia , Células Th2/patologiaRESUMO
BACKGROUND Acute lymphocytic leukemia (ALL) is a common blood cancer which induces high mortality in children. Bromodomains and extra-terminal (BET) protein inhibitors, such as JQ1 and ARV-825, are promising cancer therapeutic agents that can be used by targeting c-Myc. A recent work reported that JQ1 effectively attenuates ALL in vitro by suppressing cell proliferation and accelerating apoptosis. The purpose of this research was to probe into the potential mechanism of how JQ1 inhibits ALL cell proliferation in vitro. MATERIAL AND METHODS Cell viability of ALL cells were measured by CTG after treatment by JQ1. Cell cycle analysis was done by EdU and PI staining. Cell apoptosis was assessed by Annexin V/PI staining. Glycolysis was detected using Seahorse and LC-MS kits. The expression of glycolytic rate-limiting enzymes was assessed by RNA-seq, qRT-PCR, and Western blot. RESULTS JQ1 suppressed cell proliferation by arresting the cell cycle and inducing the apoptosis of acute lymphocytic leukemia cells. JQ1 inhibited cell proliferation of B-ALL cells by restraining glycolysis. Conversely, the cell cycle block of B-ALL cells induced by JQ1 was partially abolished after pretreatment with 2-Deoxy-D-glucose (2-DG), an inhibitor of glycolysis. Furthermore, JQ1 restrained the glycolysis of B-ALL cell lines by remarkably downregulating the rate-limiting enzymes of glycolysis, such as hexokinase 2, phosphofructokinase, and lactate dehydrogenase A. Moreover, the cell cycle arrest was reversed in B-ALL cells with overexpressed c-Myc treated by JQ1, which is involved in the enhancement of glycolysis. CONCLUSIONS The BET inhibitor JQ1 suppresses the proliferation of ALL by inhibiting c-Myc-mediated glycolysis, thus providing a new strategy for the treatment of ALL.
Assuntos
Azepinas/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Proteínas/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Triazóis/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Células HEK293 , Humanos , Proteínas Nucleares/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição/metabolismoRESUMO
Aplastic anemia (AA) is a serious blood system disease that threatens human health. At present, the main cause of this disease is believed to be immune hyperfunction. However, the specific metabolic mode involved in the occurrence of lymphocytes in AA is still unknown. In addition, whether rapamycin, a specific blocker of the mTOR signaling pathway, plays a therapeutic role by inhibiting lymphocyte metabolism remains unclear. We induced an AA mouse model through the classical immune-mediated pathway and simultaneously administered rapamycin intervention therapy. First, the AA-associated phenotypic changes and the efficacy of rapamycin in the treatment of AA were discussed. Second, the proliferation and metabolic pathway of bone marrow (BM) lymphocytes in AA and the effect of rapamycin on this process were determined. Finally, the expression levels of mTOR pathway-related proteins were analyzed. By inhibiting the mTOR signaling pathway, rapamycin could ameliorate the phenotype of the immune-mediated AA model and inhibit the proliferation of T cells by preventing cell cycle transition from G0 to G1 phase. Moreover, we found that mitochondrial oxidative phosphorylation is involved in the metabolic reprogramming of T cells in AA and that rapamycin can inhibit this process. We confirmed that mitochondrial oxidative phosphorylation is involved in the metabolic reprogramming of T cells in AA and further extended the mechanism of rapamycin in treating AA by inhibiting the mTOR signaling pathway. This viewpoint may provide a new therapeutic idea for clinical applications.
Assuntos
Anemia Aplástica/tratamento farmacológico , Imunossupressores/farmacologia , Sirolimo/farmacologia , Linfócitos T/efeitos dos fármacos , Anemia Aplástica/imunologia , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Masculino , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Linfócitos T/imunologia , Linfócitos T/patologiaRESUMO
Leucine-rich repeat containing G-protein-coupled receptor 6 (LGR6) is a member of the rhodopsin-like 7-transmembrane domain receptor superfamily and has high homology to LGR4 and LGR5. LGR6 is highly expressed in osteoblastic progenitors, and LGR6-deficient mice show nail and bone regeneration defect. However, the effect of LGR6 on the osteogenic differentiation of osteoblastic progenitors and its underlying mechanisms are largely unknown. In this study, we overexpressed and knockdown LGR6 with lentivirus in the preosteoblastic cell MC3T3-E1 to observe the effect of LGR6 on osteogenic differentiation and explore its possible molecular mechanism. LGR6 overexpression promoted osteogenic differentiation and mineralization by stabilizing ß-catenin to potentiate the Wnt/ß-catenin signaling pathway in MC3T3-E1 cells. Conversely, LGR6 knockdown inhibited osteogenic differentiation and mineralization by enhancing ß-catenin degradation to inactivate the Wnt/ß-catenin signaling pathway. These results reveal that LGR6 is highly expressed in osteoblastic progenitors, and promotes osteogenesis by enhancing ß-catenin stability to strengthen the Wnt signaling pathway. This study provides an important reference into the exact mechanisms of osteogenic differentiation.
Assuntos
Osteogênese , Receptores Acoplados a Proteínas G/metabolismo , Via de Sinalização Wnt , Animais , Calcificação Fisiológica , Diferenciação Celular , Linhagem Celular , Técnicas de Silenciamento de Genes , Camundongos , Estabilidade Proteica , Proteólise , beta Catenina/metabolismoRESUMO
Polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder, and skin changes (POEMS) syndrome is a multisystem disorder that has limited treatment options. Here, we described a case of a 55-year-old female subject who was treated for multiple drugs, but the skin symptoms continued to progress; the patient responded well to baricitinib. This suggests that JAK/STAT signaling pathways play an essential role in the pathological process of POEMS syndrome.
RESUMO
OBJECTIVE: The objective was to evaluate whether initiation of urate-lowering treatment (ULT) during an acute gout flare prolonged the current episode. METHODS: A comprehensive search of MEDLINE and Web of Science databases was conducted from their inception to 15 March 2021. Five randomized controlled trials (RCTs) with 381 patients met the inclusion criteria. Standardized mean difference (SMD), odds ratio (OR), and 95% confidence interval (CI) were used for estimating the clinical efficacy of ULT in acute gout. RESULTS: There was no statistical difference in days to resolution (intent-to-treat analysis) (SMD, 0.68; 95% CI - 0.42 to 1.78; I2, 49%; p = 0.22), the pain visual analogue score (VAS) by day 10 (SMD, - 0.07; 95% CI - 0.30 to 0.16; I2, 0%; p = 0.53), C-reactive protein (CRP) from day 7 to 10 (SMD, - 1.14; 95% CI - 5.63 to 3.36; I2, 55%; p = 0.62), erythrocyte sedimentation rate (ESR) from day 7 to 10 (SMD, - 2.51; 95% CI - 5.46 to 0.45; I2, 0%; p = 0.10) and the recurrence of gout flares within 28-30 days (OR 0.78; 95% CI 0.29 to 2.09; I2, 0%; p = 0.62). CONCLUSION: Initiation of ULT during an acute gout flare did not prolong the duration of the flare. However, larger sample size studies are needed to confirm this finding. Trial registration number PROSPERO (CRD42021234581).
Assuntos
Gota , Ácido Úrico , Gota/tratamento farmacológico , Supressores da Gota/uso terapêutico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do TratamentoRESUMO
Background and Objective: Bone erosion is common in patients with gout. The role of neutrophil-derived exosomes in gouty bone erosion remains elusive. This study aimed to investigate the functions of the neutrophil-derived exosomes in the development of bone erosion in gout. Methods: Neutrophil-derived exosomes were collected and assessed by transmission electron microscopy and nanoparticle tracking analysis. Cell counting kit-8 assay was applied to evaluate cell viability, and cell apoptosis was assessed by flow cytometry. In addition, quantitative Real-time PCR and Western blotting were used to determine the expression levels of alkaline phosphatase (ALP), osteoprotegerin (OPG), and receptor activator of nuclear factor-κB ligand (RANKL). Neutrophil-derived exosomes were tagged with PKH67. The miRNA expression profiles of exosomes and human fetal osteoblasts (hFOB) were compared using high-throughput sequencing. Functional miRNAs transfected into hFOB after co-incubation with exosomes were selected and validated by preliminary qPCR. Results: Neutrophil-derived exosomes were stimulated by monosodium urate (MSU). The exosomes could inhibit the viability of the hFOB, and the expression levels of ALP and OPG were down-regulated, while the expression level of RANKL was up-regulated. However, there was no significant difference in the viability of osteoclasts and the expression of nuclear factor of activated T cells 1. Exosomes were observed in the cytoplasm under a confocal microscopy, confirming that exosomes could be taken up by hFOB. In total, 2590 miRNAs were found, of which 47 miRNAs were differentially expressed. Among the delivered miRNAs, miR-1246 exhibited the highest level of differential expression. The viability of hFOB was reduced by miR-1246 mimics and increased by miR-1246 inhibitors. There was no significant difference in hFOB apoptosis rate between the miR-1246 mimic and miR-1246 inhibitor group. MiR-1246 overexpression decreased the expression levels of ALP and OPG, whereas increasing the expression level of RANKL. In contrast, miR-1246 inhibitor increased the expression levels of ALP and OPG, while decreasing the expression level of RANKL. Neutrophil-derived exosomes stimulated by MSU could increase the expression of miR-1246. Conclusion: Neutrophil-derived exosomes stimulated by MSU could inhibit the viability of osteoblasts.
Assuntos
Exossomos , Gota , MicroRNAs , Exossomos/metabolismo , Gota/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Neutrófilos/metabolismo , Osteoblastos/metabolismo , Ácido Úrico/metabolismoRESUMO
Abstract Objective: The objective was to evaluate whether initiation of urate-lowering treatment (ULT) during an acute gout flare prolonged the current episode. Methods: A comprehensive search of MEDLINE and Web of Science databases was conducted from their inception to 15 March 2021. Five randomized controlled trials (RCTs) with 381 patients met the inclusion criteria. Standardized mean difference (SMD), odds ratio (OR), and 95% confidence interval (CI) were used for estimating the clinical efficacy of ULT in acute gout. Results: There was no statistical difference in days to resolution (intent-to-treat analysis) (SMD, 0.68; 95% CI — 0.42 to 1.78; I2, 49%; p = 0.22), the pain visual analogue score (VAS) by day 10 (SMD, — 0.07; 95% CI — 0.30 to 0.16; I2, 0%; p = 0.53), C-reactive protein (CRP) from day 7 to 10 (SMD, — 1.14; 95% CI — 5.63 to 3.36; I2, 55%; p = 0.62), erythrocyte sedimentation rate (ESR) from day 7 to 10 (SMD, — 2.51; 95% CI — 5.46 to 0.45; I2, 0%; p = 0.10) and the recurrence of gout flares within 28-30 days (OR 0.78; 95% CI 0.29 to 2.09; I2, 0%; p = 0.62). Conclusion: Initiation of ULT during an acute gout flare did not prolong the duration of the flare. However, larger sample size studies are needed to confirm this finding. Trial registration number PROSPERO (CRD42021234581).