RESUMEN
PURPOSE: Napabucasin (NP) is a natural compound that can suppress cancer cell proliferation and cell cycle by inhibition of the signal transducer and activator of transcription 3 (STAT3) gene. We examined the effects of NP on the proliferation and invasion of neuroblastoma cells (SH-SY5Y). METHODS: Human neuroblastoma SH-SY5Y cell line was used in this study. NP was administered to groups at the doses of 0.3-1 µM. Cell viability was analyzed by MTT assay. Real-time quantitative reverse transcription polymerase chain reaction and western blot analysis assessed the expressions of interleukin (IL)-6 dependent Jak2/Stat3 signaling pathway. The MTT cell viability method was applied to determine the antagonistic-synergistic effects and inhibitory concentration (IC50) doses of doxorubicin (DX) and NP. RESULTS: It was determined that 0.3-1 µM doses of NP killed the cells almost completely after 48 hours, and also that Jak2/Stat3 expressions decreased dose-dependently via IL-6. At the protein level, NP and DX were found to reduce Jak2 and Stat3 levels. CONCLUSIONS: NP showed that it suppresses the proliferation of neuroblastoma cells. Due to its inhibitory effect on Jak2 and Stat3, it can be used to prevent invasion of SH-SY5Y cells. NP, which can inactivate Jak2/Stat3, can be used as a treatment agent by combining with DX in proliferation pathway in neuroblastoma.
Asunto(s)
Benzofuranos , Proliferación Celular , Supervivencia Celular , Doxorrubicina , Janus Quinasa 2 , Neuroblastoma , Factor de Transcripción STAT3 , Transducción de Señal , Humanos , Janus Quinasa 2/metabolismo , Janus Quinasa 2/efectos de los fármacos , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral , Transducción de Señal/efectos de los fármacos , Doxorrubicina/farmacología , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/patología , Supervivencia Celular/efectos de los fármacos , Benzofuranos/farmacología , Interleucina-6/metabolismo , Western Blotting , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , NaftoquinonasRESUMEN
The cell-intrinsic mechanisms underlying the decision of a stem/progenitor cell to either proliferate or differentiate remain incompletely understood. Here, we identify the transmembrane protein Lrig1 as a physiological homeostatic regulator of FGF2-driven proliferation and self-renewal of neural progenitors at early-to-mid embryonic stages of cortical development. We show that Lrig1 is expressed in cortical progenitors (CPs), and its ablation caused expansion and increased proliferation of radial/apical progenitors and of neurogenic transit-amplifying Tbr2+ intermediate progenitors. Notably, our findings identify a previously unreported EGF-independent mechanism through which Lrig1 negatively regulates neural progenitor proliferation by modulating the FGF2-induced IL6/Jak2/Stat3 pathway, a molecular cascade that plays a pivotal role in the generation and maintenance of CPs. Consistently, Lrig1 knockout mice showed a significant increase in the density of pyramidal glutamatergic neurons placed in superficial layers 2 and 3 of the postnatal neocortex. Together, these results support a model in which Lrig1 regulates cortical neurogenesis by influencing the cycling activity of a set of progenitors that are temporally specified to produce upper layer glutamatergic neurons.
Asunto(s)
Janus Quinasa 2 , Glicoproteínas de Membrana , Ratones Noqueados , Células-Madre Neurales , Neurogénesis , Neuronas , Factor de Transcripción STAT3 , Transducción de Señal , Animales , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/genética , Janus Quinasa 2/metabolismo , Células-Madre Neurales/metabolismo , Células-Madre Neurales/citología , Ratones , Neurogénesis/genética , Neuronas/metabolismo , Neuronas/citología , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Proliferación Celular , Corteza Cerebral/metabolismo , Corteza Cerebral/citología , Corteza Cerebral/embriología , Diferenciación Celular , Factores de Crecimiento de Fibroblastos/metabolismo , Proteínas del Tejido NerviosoRESUMEN
OBJECTIVE: Nasopharyngeal Carcinoma (NPC) is a malignancy of epithelium of epithelium of the nasopharynx, with the highest incidence of otolaryngeal malignancies. A growing number of studies confirm that Circular RNA (circRNA) plays an important role in tumor development, including Hsa_circ_0013561. This study aims to elucidate the process and mechanism of NPC regulation hsa_circ_0013561. METHODS: In this study, circRNA expression nodes and subcellular localization in NPC tissues were analyzed by fluorescence in situ hybridization. The expression of hsa_circ_0013561 in NPC cells was further clarified by RT-qPCR. At the same time, the lentivirus vector interfered by hsa_circ_0013561 was constructed and transfected. The cell proliferation was detected by CCK-8 method, EdU assay and plate cloning assay. The cell cycle and apoptosis were detected by flow cytometry, and the cell migration ability was detected by wound healing assay and Transwell assay. Western blotting examined the expression of apoptosis, Epithelial-Mesenchymal Transition (EMT)-associated proteins, and Janus Kinase/Signal Transductor and Activator of Transcription (JAK/STAT) signaling pathway-related proteins. RESULTS: The results showed that the expression of hsa_circ_0013561 in NPC samples was significantly upregulated and hsa_circ_0013561 localized in the cytoplasm. After down-regulating hsa_circ_0013561 expression, it significantly inhibited the proliferation and metastasis ability of NPC, inhibited EMT progression, and promoted apoptosis. Further studies showed that interference hsa_circ_0013561 significantly inhibited JAK2/STAT3 signaling pathway activation and induced the expression of apoptosis-related proteins. CONCLUSION: In summary, we found that hsa_circ_0013561 is a pro-tumor circRNA in NPC, which can reduce the activation of JAK2/STAT3 pathway by knocking down hsa_circ_0013561, thereby slowing down the malignant progression of NPC. OXFORD CENTRE FOR EVIDENCE-BASED MEDICINE 2011 LEVELS OF EVIDENCE: Level 4.
Asunto(s)
MicroARNs , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , ARN Circular/genética , ARN Circular/metabolismo , Hibridación Fluorescente in Situ , Línea Celular Tumoral , Transducción de Señal/genética , Proliferación Celular/genética , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patología , MicroARNs/genética , Regulación Neoplásica de la Expresión Génica , Janus Quinasa 2/genética , Janus Quinasa 2/metabolismo , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismoRESUMEN
OBJECTIVE: Trastuzumab is the preferred drug for the treatment of breast cancer. However, research on the cellular mechanisms of trastuzumab's potential cardiotoxicity is insufficient. The purpose of this study was to explore the toxic effects and potential mechanism of action of trastuzumab on cardiomyocytes. METHOD: Human Cardiomyocyte (HCM) viability was assessed using the MTT method. HCM apoptosis was detected using the Hoechst33342/PI Fluorescent staining. The LDH and CK activities of the cell were measured using commercially available LDH and CK assay kits. The expression levels of Notch2, JAK2, STAT3, cleaved caspase 3, bax, and bcl 2 in HCMs were detected using western blotting. RESULTS: The results showed that 250 mg/L trastuzumab induced cardiomyocyte injury and apoptosis, inhibited viability, activated the Notch2 receptor, and inhibited JAK2/STAT3 expression in HCM. Inhibition of Notch2 expression in HCM by targeted siNotch2 transfection reversed the trastuzumab-induced injury and apoptosis, and the expression of JAK2/STAT3 returned to normal levels. CONCLUSIONS: Trastuzumab induces Notch2 expression by inhibiting the JAK2/STAT3 pathway of HCMs, promotes cell apoptosis, and causes cardiomyocyteinjury. Notch2 may be a potential target of trastuzumab-inducedmyocardial injury. This experiment reveals the mechanism of trastuzumab-induced cardiotoxicity, providing a theoretical basis for the application of trastuzumab.
Asunto(s)
Cardiotoxicidad , Miocitos Cardíacos , Humanos , Miocitos Cardíacos/metabolismo , Trastuzumab/efectos adversos , Trastuzumab/metabolismo , Cardiotoxicidad/etiología , Cardiotoxicidad/metabolismo , Receptor Notch2/metabolismo , Apoptosis , Janus Quinasa 2/metabolismo , Janus Quinasa 2/farmacología , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/farmacologíaRESUMEN
In cancer, tumor cells and their neoplastic microenvironment can sculpt the immunogenic phenotype of a developing tumor. In this context, natural killer (NK) cells are subtypes of lymphocytes of the innate immune system recognized for their potential to eliminate neoplastic cells, not only through direct cytolytic activity but also by favoring the development of an adaptive antitumor immune response. Even though the protective effect against leukemia due to NK-cell alloreactivity mediated by the absence of the KIR-ligand has already been shown, and some data on the role of NK cells in myeloproliferative neoplasms (MPN) has been explored, their mechanisms of immune escape have not been fully investigated. It is still unclear whether NK cells can affect the biology of BCR-ABL1-negative MPN and which mechanisms are involved in the control of leukemic stem cell expansion. Aiming to investigate the potential contribution of NK cells to the pathogenesis of MPN, we characterized the frequency, receptor expression, maturation profile, and function of NK cells from a conditional Jak2V617F murine transgenic model, which faithfully resembles the main clinical and laboratory characteristics of human polycythemia vera, and MPN patients. Immunophenotypic analysis was performed to characterize NK frequency, their subtypes, and receptor expression in both mutated and wild-type samples. We observed a higher frequency of total NK cells in JAK2V617F mutated MPN and a maturation arrest that resulted in low-numbered mature CD11b+ NK cells and increased immature secretory CD27+ cells in both human and murine mutated samples. In agreement, inhibitory receptors were more expressed in MPN. NK cells from Jak2V617F mice presented a lower potential for proliferation and activation than wild-type NK cells. Colonies generated by murine hematopoietic stem cells (HSC) after mutated or wild-type NK co-culture exposure demonstrated that NK cells from Jak2V617F mice were deficient in regulating differentiation and clonogenic capacity. In conclusion, our findings suggest that NK cells have an immature profile with deficient cytotoxicity that may lead to impaired tumor surveillance in MPN. These data provide a new perspective on the behavior of NK cells in the context of myeloid malignancies and can contribute to the development of new therapeutic strategies, targeting onco-inflammatory pathways that can potentially control transformed HSCs.
Asunto(s)
Células Asesinas Naturales , Trastornos Mieloproliferativos , Animales , Humanos , Ratones , Janus Quinasa 2/genética , Janus Quinasa 2/metabolismo , Células Asesinas Naturales/metabolismo , Leucemia/genética , Leucemia/metabolismo , Ligandos , Trastornos Mieloproliferativos/genética , Trastornos Mieloproliferativos/patología , Microambiente Tumoral/genéticaRESUMEN
Dexmedetomidine (DEX) is known to provide neuroprotection against cerebral ischemia and reperfusion injury (CIRI), but the exact mechanisms remain unclear. This study was conducted to investigate whether DEX pretreatment conferred neuroprotection against CIRI by inhibiting neuroinflammation through the JAK2/STAT3 signaling pathway. Middle cerebral artery occlusion (MCAO) was performed to establish a cerebral ischemia/reperfusion (I/R) model. Specific-pathogen-free male Sprague-Dawley rats were randomly divided into Sham, I/R, DEX, DEX+IL-6, and AG490 (a selective inhibitor of JAK2) groups. The Longa score, TTC staining, and HE staining were used to evaluate brain damage. ELISA was used to exam levels of TNF-α. Western blotting was used to assess the levels of JAK2, phosphorylated-JAK2 (p-JAK2), STAT3, and phosphorylated-STAT3 (p-STAT3). Our results suggested that both pretreatment with DEX and AG490 decreased the Longa score and cerebral infarct areas following cerebral I/R. After treatment with IL-6, the effects of DEX on abrogating these pathological changes were reduced. HE staining revealed that I/R-induced neuronal pathological changes were attenuated by DEX application, consistent with the AG490 group. However, these effects of DEX were abolished by IL-6. Furthermore, TNF-α levels were significantly increased in the I/R group, accompanied by an increase in the levels of the p-JAK2 and p-STAT3. DEX and AG490 pretreatment down-regulated the expressions of TNF-α, p-JAK2, and p-STAT3. In contrast, the down-regulation of TNF-α, p-JAK2, and p-STAT3 induced by DEX was reversed by IL-6. Collectively, our results indicated that DEX pretreatment conferred neuroprotection against CIRI by inhibiting neuroinflammation via negatively regulating the JAK2/STAT3 signaling pathway.
Asunto(s)
Isquemia Encefálica , Dexmedetomidina , Daño por Reperfusión , Animales , Apoptosis , Isquemia Encefálica/complicaciones , Dexmedetomidina/farmacología , Dexmedetomidina/uso terapéutico , Interleucina-6/metabolismo , Janus Quinasa 2/metabolismo , Janus Quinasa 2/farmacología , Masculino , Enfermedades Neuroinflamatorias , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/complicaciones , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/prevención & control , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/farmacología , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Myeloproliferative neoplasms (MPN) belong to a group of clonal diseases of hematopoietic stem cells characterized by aberrant proliferation of mature myeloid lineages. The constitutive activation of the JAK2/STAT signaling pathway is now well established to play a central role in MPN pathogenesis; however, accumulating evidence now indicates that the IGF1R-mediated signaling pathway contributes to the maintenance of the malignant phenotype. Studies using inhibitors of IGF1-mediated signaling have reported cytotoxic effects in cellular and murine models of MPN, but no consensus has been reached regarding the potency and efficacy of inhibitors of the IGF1R-related pathway in this context. In the present study, we compared the potency and efficacy of three inhibitors of IGF1R-related pathways in a JAK2V617F-driven cellular model. These inhibitors (NT157, OSI-906, and NVP-AEW54) present antineoplastic activity with similar efficacy in Ba/F3 JAK2V617F cells, with NT157 showing the greatest potency. Both the induction of apoptosis and reduction in cell proliferation were associated with the observed reduction in cell viability. Downregulation of JAK2/STAT signaling was an advantageous off-target effect of all three inhibitors. These preclinical studies reinforce the potential of the IGF1R-related pathway as a therapeutic target in MPN.
Asunto(s)
Antineoplásicos , Trastornos Mieloproliferativos , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis , Proliferación Celular , Janus Quinasa 2/metabolismo , Ratones , Mutación , Trastornos Mieloproliferativos/tratamiento farmacológico , Trastornos Mieloproliferativos/genética , Trastornos Mieloproliferativos/patología , Receptor IGF Tipo 1/metabolismo , Transducción de SeñalRESUMEN
Toll-like receptors (TLRs) are a family of transmembrane receptors whose signaling control cellular processes of cell proliferation, survival, apoptosis, angiogenesis, remodeling, and repair of tissues. Polymorphisms in TLR genes can change the balance between pro and anti-inflammatory cytokines, modulating the risk of infection, chronic inflammation, and cancer. Although many studies have demonstrated the direct involvement of TLR signaling in the benefit of tumor cells in certain cancers, little is known about the influence of these gene polymorphisms on myeloproliferative neoplasms (MPNs). In this context, the objective of the study was to investigate a possible association between the TLR polymorphisms and the development of MPNs. 167 patients diagnosed with MPN and 222 healthy controls from the same region were evaluated. Genomic DNA was extracted and the TLR2 (rs5743708), TLR4 (rs4986790, rs4986791), TLR9 (rs5743836, rs187084) and JAK2V617F polymorphisms were genotyped by PCR-RFLP. The statistical analysis was performed by OpenEpi and SNPstat software. The JAK2V617F mutation was found in 68.32% of patients. TLR9-1486C/T CT genotype was less frequent in patients with polycythemia vera (PV) (OR 0.39, 95% CI 0.20-0.78, P = 0.025). When haplotype frequencies were analyzed, -1237T/-1486C (TLR9) was also less frequent in men (OR 0.58, 95% CI 0.36-0.94) and JAK negative men patients (OR 0.43, 95% CI 0.21-0.88). We can infer that the TLR9-1486 CT genotype could be associated with protection for PV and the TLR9-1237T/-1486C haplotype, protection for men, as well as for JAK negative men patients with MPN. There were no associations between TLR2 and TLR4 gene polymorphisms and MPN.
Asunto(s)
Neoplasias de la Médula Ósea/genética , Janus Quinasa 2/genética , Receptor Toll-Like 9/genética , Receptores Toll-Like/genética , Adulto , Anciano , Neoplasias de la Médula Ósea/metabolismo , Femenino , Haplotipos/genética , Humanos , Janus Quinasa 2/metabolismo , Masculino , Persona de Mediana Edad , Trastornos Mieloproliferativos/genética , Policitemia Vera/genética , Polimorfismo de Nucleótido Simple/genética , Mielofibrosis Primaria/genética , Trombocitemia Esencial/genética , Receptor Toll-Like 2/genética , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo , Receptor Toll-Like 9/metabolismo , Receptores Toll-Like/metabolismoRESUMEN
Non-nutritive sweeteners (NNSs) are commonly used to prevent weight gain and development of metabolic diseases associated with consumption of high-energy diets. Recent studies have demonstrated that these compounds may have unwanted detrimental effects under specific circumstances in vivo. In particular, an association between NNS consumption and changes in signaling pathways involved in the hunger-satiety system in the brain has been reported. Nonetheless, the extent of alterations in brain signaling pathways associated with consumption of these compounds has not been determined. The objective of this study was to determine the effect of frequent consumption of NNSs on the expression of proteins involved in signaling pathways related to appetite control in the brain in vivo. Eight-week-old BALB/c mice were supplemented with sucrose, sucralose, or steviol glycosides in their daily drinking water for 6 weeks. Subsequently, total brain protein extracts were used to analyze the expression of total and phosphorylated JAK2, STAT5, ERK 1/2, JNK, as well as SHP-2 and POMC, by western blot. Serum concentrations of leptin and α-MSH were quantified by ELISA. Results show that consumption of NNSs promotes significant changes in these signaling pathways, reducing the expression of pSTAT5/STAT5, pERK 1/2, SHP-2, and pJNK/JNK in male mice supplemented with steviol glycosides. Furthermore, consumption of steviol glycosides induced a decrease of α-MSH in male mice. In contrast, steviol glycosides induced overexpression of pSTAT5, pERK, and SHP-2 in females. These data suggest that chronic consumption of NNSs promotes sex-specific changes in signaling pathways related to the central hunger-satiety system in vivo.
Asunto(s)
Regulación del Apetito , Encéfalo/efectos de los fármacos , Edulcorantes no Nutritivos/farmacología , Transducción de Señal , Animales , Encéfalo/metabolismo , Encéfalo/fisiología , Femenino , Janus Quinasa 2/metabolismo , MAP Quinasa Quinasa 4/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Proopiomelanocortina/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Factor de Transcripción STAT5/metabolismoRESUMEN
We addressed the involvement of the receptor for advanced glycation end products (RAGE) in the impairment of the cellular cholesterol efflux elicited by glycated albumin. Albumin was isolated from type 1 (DM1) and type 2 (DM2) diabetes mellitus (HbA1c > 9%) and non-DM subjects (C). Moreover, albumin was glycated in vitro (AGE-albumin). Macrophages from Ager null and wild-type (WT) mice, or THP-1 transfected with siRNA-AGER, were treated with C, DM1, DM2, non-glycated or AGE-albumin. The cholesterol efflux was reduced in WT cells exposed to DM1 or DM2 albumin as compared to C, and the intracellular lipid content was increased. These events were not observed in Ager null cells, in which the cholesterol efflux and lipid staining were, respectively, higher and lower when compared to WT cells. In WT, Ager, Nox4 and Nfkb1, mRNA increased and Scd1 and Abcg1 diminished after treatment with DM1 and DM2 albumin. In Ager null cells treated with DM-albumin, Nox4, Scd1 and Nfkb1 were reduced and Jak2 and Abcg1 increased. In AGER-silenced THP-1, NOX4 and SCD1 mRNA were reduced and JAK2 and ABCG1 were increased even after treatment with AGE or DM-albumin. RAGE mediates the deleterious effects of AGE-albumin in macrophage cholesterol efflux.
Asunto(s)
HDL-Colesterol/sangre , LDL-Colesterol/sangre , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Macrófagos/metabolismo , Receptor para Productos Finales de Glicación Avanzada/genética , Adulto , Animales , Estudios de Casos y Controles , Línea Celular , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patología , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patología , Femenino , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Regulación de la Expresión Génica , Hemoglobina Glucada/genética , Hemoglobina Glucada/metabolismo , Productos Finales de Glicación Avanzada/sangre , Productos Finales de Glicación Avanzada/farmacología , Humanos , Janus Quinasa 2/genética , Janus Quinasa 2/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , NADPH Oxidasa 4/genética , NADPH Oxidasa 4/metabolismo , Subunidad p50 de NF-kappa B/genética , Subunidad p50 de NF-kappa B/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Receptor para Productos Finales de Glicación Avanzada/antagonistas & inhibidores , Receptor para Productos Finales de Glicación Avanzada/deficiencia , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Albúmina Sérica Humana/metabolismo , Albúmina Sérica Humana/farmacología , Células THP-1 , Triglicéridos/sangreRESUMEN
JAK2V617F can mimic growth factor signaling, leading to PI3K/AKT/mTOR activation and inhibition of autophagy. We hypothesized that selective inhibition of JAK1/2 by ruxolitinib could induce autophagy and limit drug efficacy in myeloproliferative neoplasms (MPN). Therefore, we investigated the effects of ruxolitinib treatment on autophagy-related genes and cellular processes, to determine the potential benefit of autophagy inhibitors plus ruxolitinib in JAK2V617F cells, and to verify the frequency and clinical impact of autophagy-related gene mutations in patients with MPNs. In SET2 JAK2V617F cells, ruxolitinib treatment induced autophagy and modulated 26 out of 79 autophagy-related genes. Ruxolitinib treatment reduced the expressions of important autophagy regulators, including mTOR/p70S6K/4EBP1 and the STAT/BCL2 axis, in a dose- and time-dependent manner. Pharmacological inhibition of autophagy was able to significantly suppress ruxolitinib-induced autophagy and increased ruxolitinib-induced apoptosis. Mutations in autophagy-related genes were found in 15.5% of MPN patients and were associated with increased age and a trend towards worse survival. In conclusion, ruxolitinib induces autophagy in JAK2V617F cells, potentially by modulation of mTOR-, STAT- and BCL2-mediated signaling. This may lead to inhibition of apoptosis. Our results suggest that the combination of ruxolitinib with pharmacological inhibitors of autophagy, such as chloroquine, may be a promising strategy to treat patients with JAK2V617F-mutated MPNs.
Asunto(s)
Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Janus Quinasa 2/metabolismo , Pirazoles/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación/efectos de los fármacos , Trastornos Mieloproliferativos/tratamiento farmacológico , Trastornos Mieloproliferativos/metabolismo , Nitrilos , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Pirimidinas , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Adulto JovenRESUMEN
BACKGROUND: Increased Rho-kinase activity in circulating leucocytes is observed in heart failure with reduced ejection fraction (HFrEF). However, there is little information in HFrEF regarding other Rho-kinase pathway components an on the relationship between Rho-kinase and apoptosis. Here, Rho-kinase activation levels and phosphorylation of major downstream molecules and apoptosis levels were measured for the first time both in HFrEF patients and healthy individuals. METHODS: Cross-sectional study comparing HFrEF patients (n = 20) and healthy controls (n = 19). Rho-kinase activity in circulating leucocytes (peripheral blood mononuclear cells, PBMCs) was determined by myosin light chain phosphatase 1 (MYPT1) and ezrin-radixin-moesin (ERM) phosphorylation. Rho-kinase cascade proteins phosphorylation p38-MAPK, myosin light chain-2, JAK and JNK were also analysed along with apoptosis. RESULTS: MYPT1 and ERM phosphorylation were significantly elevated in HFrEF patients, (3.9- and 4.8-fold higher than in controls, respectively). JAK phosphorylation was significantly increased by 300% over controls. Phosphorylation of downstream molecules p38-MAPK and myosin light chain-2 was significantly higher by 360% and 490%, respectively, while JNK phosphorylation was reduced by 60%. Catecholamine and angiotensin II levels were significantly higher in HFrEF patients, while angiotensin-(1-9) levels were lower. Apoptosis in circulating leucocytes was significantly increased in HFrEF patients by 2.8-fold compared with controls and significantly correlated with Rho-kinase activation. CONCLUSION: Rho-kinase pathway is activated in PMBCs from HFrEF patients despite optimal treatment, and it is closely associated with neurohormonal activation and with apoptosis. ROCK cascade inhibition might induce clinical benefits in HFrEF patients, and its assessment in PMBCs could be useful to evaluate reverse remodelling and disease regression.
Asunto(s)
Apoptosis , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/fisiopatología , Leucocitos Mononucleares/enzimología , Leucocitos Mononucleares/patología , Transducción de Señal , Volumen Sistólico , Quinasas Asociadas a rho/metabolismo , Angiotensinas/sangre , Animales , Antígenos CD/metabolismo , Catecolaminas/sangre , Citocinas/sangre , Proteínas del Citoesqueleto/metabolismo , Modelos Animales de Enfermedad , Activación Enzimática , Femenino , Insuficiencia Cardíaca/diagnóstico por imagen , Humanos , Janus Quinasa 2/metabolismo , Masculino , Proteínas de la Membrana/metabolismo , Proteínas de Microfilamentos/metabolismo , Persona de Mediana Edad , Miocardio/patología , Fosfatasa de Miosina de Cadena Ligera/metabolismo , Péptido Natriurético Encefálico/sangre , Fosforilación , Ratas , Sístole , Remodelación VentricularRESUMEN
BACKGROUND/AIMS: Cholinergic signalling mediated by the activation of muscarinic and nicotinic receptors has been described in the literature as a classic and important signalling pathway in the regulation of the inflammatory response. Recent research has investigated the role of acetylcholine, the physiological agonist of these receptors, in the control of energy homeostasis at the central level. Studies have shown that mice that do not express acetylcholine in brain regions regulating energy homeostasis present with excessive weight gain and hyperphagia. However, it has not yet been well-described in the literature which cholinergic receptor subunits are involved in this response; moreover, the signalling pathways responsible for the observed effects are not fully delineated. The hypothalamus is the regulating centre of energy homeostasis, and the α7 subunit of the nicotinic acetylcholine receptor (α7nAChR) is highly expressed in this region. When active, α7nAChR recruits proteins such as JAK2/STAT3 to mediate its signalling; the same intracellular components are required by leptin, an anorexigenic hormone. The aim of the present study was to evaluate the role of the hypothalamic α7nAChR in the control of energy homeostasis. METHODS: The work was performed on Swiss male mice. Initially, using immunofluorescent staining on brain sections, the presence of α7nAChR in hypothalamic cells regulating energy homeostasis was evaluated. Animals were submitted to stereotaxis in the lateral ventricle and intracerebroventricular stimulation (ICV) was used for the administration of an agonist (PNU) or antagonist (α-bungarotoxin) of α7nAChR. Metabolic parameters were evaluated and the expression of neuropeptides was evaluated in the hypothalamus by real-time PCR and western blot. The expression of hypothalamic neuropeptides was evaluated in mice treated with siRNA or inhibitors of JAK2/STAT3 (AG490 and STATTIC) proteins. We also evaluated food intake in α7nAChR knockout animals (α7KO). Additionally, in mouse hypothalamic cell culture (the mypHoA-POMC/GFP lineage), we evaluated the expression of neuropeptides and pSTAT3 after stimulation with PNU. RESULTS: Our results indicate co-localisation of α7nAChR with α-MSH, AgRP and NPY in hypothalamic cells. Pharmacological activation of α7nAChR reduced food intake and increased hypothalamic POMC expression and decreased NPY and AgRP mRNA levels and the protein content of pAMPK. Inhibition of α7nAChR with an antagonist increased the mRNA content of NPY and AgRP. Inhibition of α7nAChR with siRNA led to the suppression of POMC expression and an increase in AgRP mRNA levels. α7KO mice showed no changes in food intake. Inhibition of proteins involved in the JAK2/STAT3 signalling pathway reversed the effects observed after PNU stimulation. POMC-GFP cells, when treated with PNU, showed increased POMC expression and nuclear translocation of pSTAT3. CONCLUSION: Thus, selective activation of α7nAChR is able to modulate important markers of the response to food intake, suggesting that α7nAChR activation can suppress the expression of orexigenic markers and favour the expression of anorexics using the intracellular JAK2/STAT3 machinery.
Asunto(s)
Proteína Relacionada con Agouti/metabolismo , Janus Quinasa 2/metabolismo , Proopiomelanocortina/metabolismo , Factor de Transcripción STAT3/metabolismo , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo , Proteína Relacionada con Agouti/genética , Animales , Benzamidas/farmacología , Compuestos Bicíclicos con Puentes/farmacología , Bungarotoxinas/farmacología , Línea Celular , Ingestión de Alimentos/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Janus Quinasa 2/antagonistas & inhibidores , Janus Quinasa 2/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neuronas/metabolismo , Proopiomelanocortina/genética , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Factor de Transcripción STAT3/antagonistas & inhibidores , Factor de Transcripción STAT3/genética , Transducción de Señal/efectos de los fármacos , Receptor Nicotínico de Acetilcolina alfa 7/agonistas , Receptor Nicotínico de Acetilcolina alfa 7/antagonistas & inhibidores , Receptor Nicotínico de Acetilcolina alfa 7/genéticaRESUMEN
JAK2/STAT signaling participates in the Ph-negative myeloproliferative neoplasms (MPN) pathophysiology and has been targeted by ruxolitinib, a JAK1/2 inhibitor. In the present study, the impact of ruxolitinib treatment on cytoskeleton-related genes expression was explored. In SET2 cells, AURKA and AURKB expression/activity were downregulated in a dose- and time-dependent manner by ruxolitinib. Reversine, a multikinase inhibitor selective for aurora kinases, reduced cell viability in a dose- and/or time-dependent manner in JAK2V617F cells. Reversine significantly increased apoptosis and mitotic catastrophe, and reduced cell proliferation and clonogenic capacity in SET2 and HEL cells. In the molecular scenario, reversine induced DNA damage and apoptosis markers, as well as, reduced AURKA and AURKB expression/activity. In SET2 cells, reversine modulated the expression of 32 out of 84 apoptosis-related genes investigated, including downregulation of antiapoptotic (BCL2, BCL2L1, and BIRC5) and upregulation of proapoptotic (BIK, BINP3, and BNIP3L) genes. Synergism experiments indicated that low dose of reversine had a potentiating effect under ruxolitinib treatment at low doses in SET2 cells. In summary, our exploratory study establishes new targets, related to the regulation of the cellular cytoskeleton, for potential pharmacological intervention in MPN. These findings indicate that AURKA and AURKB participate in the JAK2/STAT signaling pathway and contribute to the MPN phenotype.
Asunto(s)
Apoptosis , Biomarcadores de Tumor/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Janus Quinasa 2/metabolismo , Morfolinas/farmacología , Mutación , Trastornos Mieloproliferativos/patología , Purinas/farmacología , Aurora Quinasa A/genética , Aurora Quinasa A/metabolismo , Aurora Quinasa B/genética , Aurora Quinasa B/metabolismo , Biomarcadores de Tumor/genética , Ciclo Celular , Proliferación Celular , Humanos , Janus Quinasa 2/genética , Trastornos Mieloproliferativos/genética , Trastornos Mieloproliferativos/metabolismo , Inhibidores de Proteínas Quinasas , Células Tumorales CultivadasRESUMEN
BACKGROUND: Acute kidney injury (AKI), which is mainly caused by sepsis, has high morbidity and mortality rates. CXCL8(3-72) K11R/G31P (G31P) can exert therapeutic effect on inflammatory diseases and malignancies. We aimed to investigate the effect and mechanism of G31P on septic AKI. METHODS: An AKI mouse model was established, and kidney injury was assessed by histological analysis. The contents of serum creatinine (SCr) and blood urea nitrogen (BUN) were measured by commercial kits, whereas neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) were detected by enzyme-linked immunosorbent assay (ELISA) kits. The expressions of CXCL8 in serum and kidney tissues were determined using ELISA and immunohistochemical analysis, respectively. Apoptosis rate of renal tissue was detected by terminal deoxynucleotidyl transfer-mediated dUTP nick end labeling (TUNEL) analysis. The expressions of inflammatory cytokines were measured by quantitative real-time PCR and Western blot, respectively. The apoptosis-related proteins, JAK2, STAT3, NF-κB and IκB were determined by Western blot. RESULTS: G31P could reduce the levels of SCr, BUN, HGAL and KIM-1 and inhibit the renal tissue injury in AKI mice. G31P was also found to suppress the serum and nephric CXCL8 expressions and attenuated the apoptosis rate. The levels of inflammatory cytokines, pro-apoptotic proteins were decreased, while the anti-apoptotic proteins were increased by G31P in AKI mice. G31P also inhibited the activation of JAK2, STAT3 and NF-κB in AKI mice. CONCLUSION: These results suggest that G31P could protect renal function and attenuate the septic AKI. Our findings provide a potential target for the treatment of AKI.
Asunto(s)
Lesión Renal Aguda/etiología , Janus Quinasa 2/metabolismo , FN-kappa B/metabolismo , Factor de Transcripción STAT3/metabolismo , Sepsis/complicaciones , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/patología , Animales , Apoptosis , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos C57BL , Sepsis/patología , Transducción de SeñalRESUMEN
Prolactinomas are increasingly viewed as a "problem of signal transduction." Consequently, the identification of factors and signaling pathways that control lactotrope cell turnover is needed in order to encourage new therapeutic developments. We have previously shown that prolactin (PRL) acts as a proapoptotic and antiproliferative factor on lactotropes, maintaining anterior pituitary cell homeostasis, which contrasts with the classical antiapoptotic and/or proliferative actions exerted by PRL in most other target tissues. We aimed to investigate the PRLR-triggered signaling pathways mediating these nonclassical effects of PRL in the pituitary. Our results suggest that (i) the PRLR/Jak2/STAT5 pathway is constitutively active in GH3 cells and contributes to PRL-induced apoptosis by increasing the Bax/Bcl-2 ratio, (ii) PRL inhibits ERK1/2 and Akt phosphorylation, thereby contributing to its proapoptotic effect, and (iii) the PI3K/Akt pathway participates in the PRL-mediated control of lactotrope proliferation. We hypothesize that the alteration of PRL actions in lactotrope homeostasis due to the dysregulation of any of the mechanisms of actions described above may contribute to the pathogenesis of prolactinomas.
Asunto(s)
Apoptosis/efectos de los fármacos , Janus Quinasa 2/metabolismo , Lactotrofos/metabolismo , Prolactina/farmacología , Factor de Transcripción STAT5/metabolismo , Transducción de Señal/fisiología , Animales , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Femenino , Lactotrofos/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Wistar , Receptores de Prolactina/antagonistas & inhibidores , Receptores de Prolactina/metabolismo , Transducción de Señal/efectos de los fármacosRESUMEN
BACKGROUND: Acute kidney injury (AKI), which is mainly caused by sepsis, has high morbidity and mortality rates. CXCL8(3-72) K11R/G31P (G31P) can exert therapeutic effect on inflammatory diseases and malignancies. We aimed to investigate the effect and mechanism of G31P on septic AKI. METHODS: An AKI mouse model was established, and kidney injury was assessed by histological analysis. The contents of serum creatinine (SCr) and blood urea nitrogen (BUN) were measured by commercial kits, whereas neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) were detected by enzyme-linked immunosorbent assay (ELISA) kits. The expressions of CXCL8 in serum and kidney tissues were determined using ELISA and immunohistochemical analysis, respectively. Apoptosis rate of renal tissue was detected by terminal deoxynucleotidyl transfer-mediated dUTP nick end labeling (TUNEL) analysis. The expressions of inflammatory cytokines were measured by quantitative real-time PCR and Western blot, respectively. The apoptosis-related proteins, JAK2, STAT3, NF-κB and IκB were determined by Western blot. RESULTS: G31P could reduce the levels of SCr, BUN, HGAL and KIM-1 and inhibit the renal tissue injury in AKI mice. G31P was also found to suppress the serum and nephric CXCL8 expressions and attenuated the apoptosis rate. The levels of inflammatory cytokines, pro-apoptotic proteins were decreased, while the anti-apoptotic proteins were increased by G31P in AKI mice. G31P also inhibited the activation of JAK2, STAT3 and NF-κB in AKI mice. CONCLUSION: These results suggest that G31P could protect renal function and attenuate the septic AKI. Our findings provide a potential target for the treatment of AKI.
Asunto(s)
Animales , Masculino , Ratones , FN-kappa B/metabolismo , Sepsis/complicaciones , Factor de Transcripción STAT3/metabolismo , Janus Quinasa 2/metabolismo , Lesión Renal Aguda/etiología , Transducción de Señal , Apoptosis , Sepsis/patología , Modelos Animales de Enfermedad , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/patología , Ratones Endogámicos C57BLRESUMEN
INTRODUCTION AND AIM: Hepatocyte growth factor (HGF) has been shown to ameliorate liver inflammation and fibrosis; however, the mechanism underlying its effects in non-alcoholic steatohepatitis (NASH) is unclear. This study aimed to analyse the relationship between the JAK2-STAT3 signalling pathway and the ameliorating effect of HGF on NASH. MATERIAL AND METHODS: Mice were fed a high-fat diet (HFD) for 16 weeks, and then plasma and hepatic tissues were collected. Histological and clinical chemistry assays were performed to assess liver disease. The mRNA and protein levels of JAK2, STAT3, and c-Met were assessed by real-time PCR and western blotting, respectively. RESULTS: Serum ALT, AST, and TG levels were increased in NASH mice. Histological analysis showed different degrees of steatosis, inflammatory infiltrates, and fibrosis in HFD animals. Exogenous administration of recombinant human (rh) HGF via the tail vein for 14 days markedly decreased ALT and AST to levels lower than those in the control group. Compared with the levels in HFD mice, c-Met, p-c-Met, JAK2, p-JAK2, and p-STAT3 levels were increased in mice that were administered HGF (P < 0.05). Furthermore, silencing of HGF or blocking of its receptor c-Met affected JAK2 and STAT3 protein phosphorylation. CONCLUSIONS: Excess HGF highly probable improved NASH liver function. Combined with its ligand, c-Met, HGF may promote the phosphorylation of JAK2-STAT3 and inhibit inflammation in NASH. Therefore, it may be potentially useful treatment for NASH.
Asunto(s)
Antiinflamatorios/farmacología , Factor de Crecimiento de Hepatocito/farmacología , Janus Quinasa 2/metabolismo , Hígado/efectos de los fármacos , Enfermedad del Hígado Graso no Alcohólico/prevención & control , Proteínas Tirosina Quinasas Receptoras/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/efectos de los fármacos , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Citocinas/sangre , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Factor de Crecimiento de Hepatocito/genética , Factor de Crecimiento de Hepatocito/metabolismo , Mediadores de Inflamación/sangre , Janus Quinasa 2/genética , Hígado/enzimología , Hígado/patología , Masculino , Ratones Endogámicos BALB C , Enfermedad del Hígado Graso no Alcohólico/enzimología , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Fosforilación , Proteínas Tirosina Quinasas Receptoras/genética , Factor de Transcripción STAT3/genética , Triglicéridos/sangreRESUMEN
Vagal stimulation (VS) during myocardial ischemia and reperfusion has beneficial effects. However, it is not known whether short-term VS applied before ischemia or at the onset of reperfusion protects the ischemic myocardium. This study was designed to determine whether short-term VS applied before ischemia or at the onset of reperfusion reduces myocardial infarct size (IS), mimicking classic preconditioning and postconditioning. A second objective was to study the participation of muscarinic and nicotinic receptors in the protection of both preischemic and reperfusion stimulation. FVB mice were subjected to 30 min of regional myocardial ischemia followed by 2 h of reperfusion without VS, with 10-min preischemic VS (pVS), or with VS during the first 10 min of reperfusion (rVS). pVS reduced IS, and this effect was abolished by atropine and wortmannin. rVS also reduced IS in a similar manner, and this effect was abolished by the α7-nicotinic acetylcholine receptor blocker methyllycaconitine. pVS increased Akt and glycogen synthase kinase (GSK)-3ß phosphorylation. No changes in Akt and GSK-3ß phosphorylation were observed in rVS. Stimulation-mediated IS protection was abolished with the JAK2 blocker AG490. rVS did not modify IL-6 and IL-10 levels in the plasma or myocardium. Splenic denervation and splenectomy did not abolish the protective effect of rVS. In conclusion, pVS and rVS reduced IS by different mechanisms: pVS activated the Akt/GSK-3ß muscarinic pathway, whereas rVS activated α7-nicotinic acetylcholine receptors and JAK2, independently of the cholinergic anti-inflammatory pathway. NEW & NOTEWORTHY Our data suggest, for the first time, that vagal stimulation applied briefly either before ischemia or at the beginning of reperfusion mimics classic preconditioning and postconditioning and reduces myocardial infarction, activating different mechanisms. We also infer an important role of α7-nicotinic receptors for myocardial protection independent of the cholinergic anti-inflammatory pathway.
Asunto(s)
Corazón/inervación , Poscondicionamiento Isquémico , Precondicionamiento Isquémico Miocárdico , Infarto del Miocardio/prevención & control , Daño por Reperfusión Miocárdica/prevención & control , Miocardio/metabolismo , Estimulación del Nervio Vago , Nervio Vago/fisiopatología , Animales , Citocinas/metabolismo , Modelos Animales de Enfermedad , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Janus Quinasa 2/metabolismo , Masculino , Ratones , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Infarto del Miocardio/fisiopatología , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Daño por Reperfusión Miocárdica/fisiopatología , Miocardio/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores Muscarínicos/metabolismo , Transducción de Señal , Factores de Tiempo , Receptor Nicotínico de Acetilcolina alfa 7/metabolismoRESUMEN
Leptin is an adipose-derived hormone that controls appetite and energy expenditure. Leptin receptors are expressed on extra-hypothalamic ventrobasal (VB) and reticular thalamic (RTN) nuclei from embryonic stages. Here, we studied the effects of pressure-puff, local application of leptin on both synaptic transmission and action potential properties of thalamic neurons in thalamocortical slices. We used whole-cell patch-clamp recordings of thalamocortical VB neurons from wild-type (WT) and leptin-deficient obese (ob/ob) mice. We observed differences in VB neurons action potentials and synaptic currents kinetics when comparing WT vs. ob/ob. Leptin reduced GABA release onto VB neurons throughout the activation of a JAK2-dependent pathway, without affecting excitatory glutamate transmission. We observed a rapid and reversible reduction by leptin of the number of action potentials of VB neurons via the activation of large conductance Ca2+-dependent potassium channels. These leptin effects were observed in thalamocortical slices from up to 5-week-old WT but not in leptin-deficient obese mice. Results described here suggest the existence of a leptin-mediated trophic modulation of thalamocortical excitability during postnatal development. These findings could contribute to a better understanding of leptin within the thalamocortical system and sleep deficits in obesity.