RESUMEN
Environmental chemicals, such as plasticizers, have been linked to increased rates of obesity, according to epidemiological studies. Acetyl triethyl citrate (ATEC) is a plasticizer that is commonly utilized in pharmaceutical products and food packaging as a non-phthalate alternative. Due to its direct contact with the human body and high leakage rate from the polymers, assessment of the potential risk of ATEC exposure at environmentally relevant low doses to human health is needed. Male C57BL/6 J mice were fed diets containing ATEC at doses of either 0.1 or 10 µg/kg per day in a period of 12 weeks to mimic the real exposure environment. The findings suggest that in C57BL/6 J mice, ATEC exposure resulted in increased body weight gain, body fat percentage, and benign hepatocytes, as well as adipocyte size. Consistent with in vivo models, ATEC treatment obviously stimulated the increase of intracellular lipid load in both mouse and human hepatocytes. Mechanically, ATEC induced the transcriptional expression of genes involved in de novo lipogenesis and lipid uptake. Using both enzyme inhibitor and small interfering RNA (siRNA) transfection, we found that stearoyl-coenzyme A desaturase 1 (SCD1) played a significant role in ATEC-induced intracellular lipid accumulation. This study for the first time provided initial evidence suggesting the obesogenic and fatty liver-inducing effect of ATEC at low doses near human exposure levels, and ATEC might be a potential environmental obesogen and its effect on human health need to be further evaluated.
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Citratos , Lipogénesis , Plastificantes , Masculino , Ratones , Humanos , Animales , Plastificantes/toxicidad , Ratones Endogámicos C57BL , Obesidad/inducido químicamente , Obesidad/metabolismo , Lípidos , Hígado , Estearoil-CoA Desaturasa/genética , Estearoil-CoA Desaturasa/metabolismoRESUMEN
Diisobutyl adipate (DIBA), as a novel non-phthalate plasticizer, is widely used in various products. However, little effort has been made to investigate whether DIBA might have adverse effects on human health. In this study, we integrated an in silico and in vitro strategy to assess the impact of DIBA on cellular homeostasis. Since numerous plasticizers could activate peroxisome proliferator-activated receptor γ (PPARγ) pathway to interrupt metabolism systems, we first utilized molecular docking to analyze interaction between DIBA and PPARγ. Results indicated that DIBA had strong affinity with the ligand-binding domain of PPARγ (PPARγ-LBD) at Histidine 499. Afterwards, we used cellular models to investigate in vitro effects of DIBA. Results demonstrated that DIBA exposure increased intracellular lipid content in murine and human hepatocytes, and altered transcriptional expression of genes related to PPARγ signaling and lipid metabolism pathways. At last, target genes regulated by DIBA were predicted and enriched for Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Protein-protein interaction (PPI) network and transcriptional factors (TFs)-genes network were established accordingly. Target genes were enriched in Phospholipase D signaling pathway, phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) and Epidermal growth factor receptor (EGFR) signaling pathway which were related to lipid metabolism. These findings suggested that DIBA exposure might disturb intracellular lipid metabolism homeostasis via targeting PPARγ. This study also demonstrated that this integrated in silico and in vitro methodology could be utilized as a high throughput, cost-saving and effective tool to assess the potential risk of various environmental chemicals on human health.
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PPAR gamma , Plastificantes , Ratones , Humanos , Animales , Plastificantes/toxicidad , PPAR gamma/metabolismo , Metabolismo de los Lípidos , Simulación del Acoplamiento Molecular , Fosfatidilinositol 3-Quinasas/metabolismo , AdipatosRESUMEN
Hepatic gluconeogenesis is the major contributor to the hyperglycemia observed in both patients and animals with type 2 diabetes. The transcription factor FOXO1 plays a dominant role in stimulating hepatic gluconeogenesis. FOXO1 is mainly regulated by insulin under physiological conditions, but liver-specific disruption of Foxo1 transcription restores normal gluconeogenesis in mice in which insulin signaling has been blocked, suggesting that additional regulatory mechanisms exist. Understanding the transcriptional regulation of Foxo1 may be conducive to the development of insulin-independent strategies for the control of hepatic gluconeogenesis. Here, we found that elevated plasma levels of adenine nucleotide in type 2 diabetes are the major regulators of Foxo1 transcription. We treated lean mice with 5'-AMP and examined their transcriptional profiles using RNA-seq. KEGG analysis revealed that the 5'-AMP treatment led to shifted profiles that were similar to db/db mice. Many of the upregulated genes were in pathways associated with the pathology of type 2 diabetes including Foxo1 signaling. As observed in diabetic db/db mice, lean mice treated with 5'-AMP displayed enhanced Foxo1 transcription, involving an increase in cellular adenosine levels and a decrease in the S-adenosylmethionine to S-adenosylhomocysteine ratio. This reduced methylation potential resulted in declining histone H3K9 methylation in the promoters of Foxo1, G6Pc, and Pepck. In mouse livers and cultured cells, 5'-AMP induced expression of more FOXO1 protein, which was found to be localized in the nucleus, where it could promote gluconeogenesis. Our results revealed that adenine nucleotide-driven Foxo1 transcription is crucial for excessive glucose production in type 2 diabetic mice.
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Diabetes Mellitus Tipo 2/genética , Proteína Forkhead Box O1/genética , Hiperglucemia/genética , Transcripción Genética/genética , Nucleótidos de Adenina/sangre , Animales , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/patología , Regulación de la Expresión Génica/genética , Gluconeogénesis/genética , Glucosa/metabolismo , Humanos , Hiperglucemia/sangre , Hiperglucemia/patología , Insulina/genética , Hígado/metabolismo , Hígado/patología , Ratones , Ratones Endogámicos NODRESUMEN
Necroptosis, a key form of programmed lytic cell death, has gained recognition as an important driver in various inflammatory diseases. Inhibition of kinase activity of receptor interaction protein kinase 1 (RIPK1), which block the activation of the necroptosis pathway has shown therapeutic potential in many human diseases. In order to find new chemotypes of RIPK1 inhibitors, a virtual screening workflow was performed and led to the discovery of 8-benzoyl-3-benzyl-1,3,8-triazaspiro[4.5]decane-2,4-dione (compound 8) as a hit compound. Further structural optimization identified a series of 2,8-diazaspiro[4.5]decan-1-one derivatives as potent RIPK1 inhibitors. Among them, compound 41 exhibited prominent inhibitory activity against RIPK1 with an IC50 value of 92 nM. Meanwhile, compound 41 showed a significant anti-necroptotic effect in a necroptosis model in U937 cells. Therefore, compound 41 could be employed as a lead compound of RIPK1 inhibitors for further structural optimization.
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Compuestos Aza , Inhibidores de Proteínas Quinasas , Proteína Serina-Treonina Quinasas de Interacción con Receptores , Compuestos de Espiro , Humanos , Apoptosis , Compuestos Aza/química , Compuestos Aza/farmacología , Necroptosis , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Quinasas/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/farmacología , Compuestos de Espiro/química , Compuestos de Espiro/farmacologíaRESUMEN
Yersinia pestis, the causative agent of plague, is able to suppress production of inflammatory cytokines IL-18 and IL-1ß, which are generated through caspase-1-activating nucleotide-binding domain and leucine-rich repeat (NLR)-containing inflammasomes. Here, we sought to elucidate the role of NLRs and IL-18 during plague. Lack of IL-18 signaling led to increased susceptibility to Y. pestis, producing tetra-acylated lipid A, and an attenuated strain producing a Y. pseudotuberculosis-like hexa-acylated lipid A. We found that the NLRP12 inflammasome was an important regulator controlling IL-18 and IL-1ß production after Y. pestis infection, and NLRP12-deficient mice were more susceptible to bacterial challenge. NLRP12 also directed interferon-γ production via induction of IL-18, but had minimal effect on signaling to the transcription factor NF-κB. These studies reveal a role for NLRP12 in host resistance against pathogens. Minimizing NLRP12 inflammasome activation may have been a central factor in evolution of the high virulence of Y. pestis.
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Inflamasomas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Peste/inmunología , Peste/metabolismo , Yersinia pestis/inmunología , Animales , Inflamasomas/inmunología , Interferón gamma/biosíntesis , Interleucina-18/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Peste/mortalidad , Transducción de SeñalRESUMEN
BACKGROUND: Osteosarcoma is a common primary malignant bone tumor susceptible to distant metastasis. The clinical outcome for patients remains poor due to the resistance to chemotherapy and lacking effective therapeutic targets. Recepteur d'origine nantais (RON), a transmembrane protein of the c-MET proto-oncogene family, has been reported to contribute to the malignant progression and bone metastasis in several tumors. The present study aimed to explore the prognostic significance of RON in primary high-grade osteosarcoma. METHODS: Immunohistochemistry (IHC) and western blotting (WB) were used to investigate the protein expression of RON in 80 surgically resected specimens (50 high-grade osteosarcoma specimens and 30 non-neoplastic bone tissues) and 6 cell lines. The χ2 test or independent-sample Student's t-test was used to assess the significance of RON difference between osteosarcoma and non-neoplastic bone tissues. The χ2 test and Fisher's exact test were used to analyze the association of RON with the clinicopathological features of osteosarcoma patients. Kaplan-Meier method and Cox proportional hazards model were used to assess the significance of RON for the survival of osteosarcoma patients. RESULTS: The results of IHC and WB observed significant overexpression of RON in osteosarcoma specimens (P < 0.001) and osteosarcoma cell lines. Moreover, immunohistochemical high expression of RON was associated with a poor response to chemotherapy (P = 0.032) as well as worse progression-free (P = 0.003) and overall (P < 0.001) survival of osteosarcoma patients. Multivariate analysis revealed that high expression of RON was independently associated with reduced progression-free (P = 0.027, HR = 2.31) and overall survival (P = 0.004, HR = 5.06) time of osteosarcoma patients. CONCLUSIONS: The present study demonstrated that high expression of RON held independent value for unfavorable survival in primary high-grade osteosarcoma. Its potential role as a therapeutic target for osteosarcoma treatment deserves further research.
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Osteosarcoma , Humanos , Inmunohistoquímica , Pronóstico , Proto-Oncogenes Mas , Proteínas Tirosina Quinasas ReceptorasRESUMEN
The epidemic of Coronavirus Disease 2019 has been a serious threat to public health worldwide. Data from 23 January to 31 March at Jiangsu and Anhui provinces in China were collected. We developed an adjusted model with two novel features: the asymptomatic population and threshold behavior in recovery. Unbiased parameter estimation identified faithful model fitting. Our model predicted that the epidemic for asymptomatic patients (ASP) was similar in both provinces. The latent periods and outbreak sizes are extremely sensitive to strongly controlled interventions such as isolation and quarantine for both asymptomatic and imported cases. We predicted that ASP serve as a more severe factor with faster outbreaks and larger outbreak sizes compared with imported patients. Therefore, we argued that the currently strict interventions should be continuously implemented, and unraveling the asymptomatic pool is critically important before preventive strategy such as vaccines.
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Infecciones Asintomáticas/epidemiología , COVID-19/epidemiología , Pandemias/estadística & datos numéricos , China/epidemiología , Brotes de Enfermedades , Humanos , Modelos Teóricos , Neumonía Viral/epidemiología , Salud Pública/estadística & datos numéricos , Cuarentena/métodos , SARS-CoV-2/patogenicidad , Aislamiento SocialRESUMEN
AIMS/HYPOTHESIS: Plasma 5'-AMP (pAMP) is elevated in mouse models of type 2 diabetes. However, the metabolic regulatory role of adenine nucleotides in type 2 diabetes remains unclear. METHODS: Adenine nucleotides and their metabolites in plasma and liver were examined by HPLC. 1H NMR-based metabolomics analysis was performed to explore the changes of metabolites in mouse models of type 2 diabetes. Na+/K+ ATPase and Na+/H+ exchanger activity were measured in response to adenine nucleotide metabolites. Human recombinant protein tyrosine phosphatase 1B (PTP1B) was used for enzyme kinetic assays. Protein binding assays were performed with microscale thermophoresis. The intracellular pH of hepatocyte AML12 cell lines was measured using the BCECF-AM method. We also analysed pAMP levels in participants with type 2 diabetes. RESULTS: Elevation of pAMP was a universal phenomenon in all mouse models of type 2 diabetes including db/db vs lean mice (13.9 ± 2.3 µmol/l vs 3.7 ± 0.9 µmol/l; p < 0.01), ob/ob vs lean mice (9.1 ± 2.0 µmol/l vs 3.9 ± 1.2 µmol/l; p < 0.01) and high-fat diet/streptozotocin-induced vs wild-type mice (6.6 ± 1.5 µmol/l vs 4.1 ± 0.9 µmol/l; p < 0.05); this elevation was required for the occurrence of hyperglycaemia in obese mice. 1H NMR-based metabolomics study following HPLC analysis revealed that the metabolite profile in wild-type mice treated with 5'-AMP was similar to that in db/db diabetic mice, especially the accumulation of a large quantity of ATP and its metabolites. The glucose-lowering drug metformin reduced the severity of hyperglycaemia both in 5'-AMP-induced wild-type mice and db/db mice. Metformin decreased the accumulation of liver ATP but not its metabolites in these hyperglycaemic mice. ATP and metformin reciprocally change cellular pH homeostasis in liver, causing opposite shifts in liver activity of PTP1B, a key negative regulator of insulin signalling. Furthermore, pAMP levels were also elevated in individuals with type 2 diabetes (45.2 ± 22.7 nmol/l vs 3.1 ± 1.9 nmol/l; p < 0.01). CONCLUSIONS/INTERPRETATION: These results reveal an emerging role for adenine nucleotide in the regulation of hyperglycaemia and provide a potential therapeutic target in obesity and type 2 diabetes.
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Adenina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Hígado/metabolismo , Nucleótidos/química , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo , Adenosina Trifosfato/metabolismo , Adulto , Animales , Estudios de Casos y Controles , Membrana Celular/metabolismo , Diabetes Mellitus Experimental/metabolismo , Modelos Animales de Enfermedad , Femenino , Hepatocitos/metabolismo , Homeostasis , Humanos , Concentración de Iones de Hidrógeno , Hiperglucemia/metabolismo , Resistencia a la Insulina , Cinética , Espectroscopía de Resonancia Magnética , Masculino , Metformina/farmacología , Ratones , Ratones Endogámicos C57BL , Persona de Mediana EdadRESUMEN
Osteosarcoma is a malignant bone tumor with extremely high invasion, metastasis and mortality. The prognosis of patients with osteosarcoma remains poor. The ErbB receptor family was found to be overexpressed in human cancers and associated with poor prognosis. However, the role of ErbB receptor family in osteosarcoma has not been fully understood. The present study aimed to investigate the clinicopathological and prognostic significances of ErbB receptors in primary osteosarcoma. Western blot (WB), reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and fluorescence in situ hybridization (FISH) were used to detect the protein and gene expression of ErbB receptors in 60 primary osteosarcoma specimens and 30 non-neoplastic bone tissues. WB and RT-qPCR analyses showed that the protein and mRNA expression levels of EGFR, ErbB3 and ErbB4 in osteosarcoma specimens were significantly higher than those in non-neoplastic bone tissues. Seventeen (28.33%), 15 (25.00%) and 15 (25.00%) osteosarcoma specimens presented with amplification of EGFR, ErbB3 and ErbB4 gene, respectively, which were significantly higher compared with non-neoplastic bone tissues. The amplification of ErbB3 and ErbB4 in osteosarcoma was associated with advanced surgical stage. The amplification of EGFR, ErbB3, ErbB4 and the co-amplification of EGFR-ErbB3, EGFR-ErbB4, ErbB3-ErbB4 was linked with poor response to chemotherapy and distant metastasis. The amplification of EGFR, ErbB3 and ErbB4, as well as their co-amplification demonstrated independent prognostic values for reduced survival time of osteosarcoma patients and may serve as potential therapeutic targets for osteosarcoma patients in the future.
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Receptores ErbB/genética , Amplificación de Genes , Osteosarcoma/genética , Osteosarcoma/patología , Adolescente , Adulto , Huesos/metabolismo , Huesos/patología , Niño , Preescolar , Supervivencia sin Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , ARN Mensajero/genética , ARN Mensajero/metabolismo , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: Osteosarcoma is a malignant bone tumor with a high potential for lung metastasis, and the prognosis for patients with metastatic disease is very poor. The interaction between fibronectin (FN) and integrin αvß3 in soft-tissue sarcoma promotes cell migration, invasion, and lung metastasis. This study aimed to investigate the prognostic significance of FN and αvß3 in osteosarcoma. METHODS: Immunohistochemistry and western blotting were used to detect the expression of FN and αvß3 in 60 osteosarcoma specimens and in 30 osteochondroma specimens. Furthermore, correlations of FN and αvß3 with the clinicopathological features of osteosarcoma patients were analyzed using the χ2 test and Fisher's exact test. Disease-free survival and overall survival of osteosarcoma patients were assessed using the Kaplan-Meier method and Cox proportional hazards model. The predictive accuracy of the model was determined by the Harrell concordance index. RESULTS: FN (P < 0.05) and αvß3 (P < 0.05) were overexpressed in osteosarcoma specimens compared with osteochondroma specimens. High FN expression was associated with a poor response to chemotherapy (P = 0.001) and poor disease-free (P < 0.001) and overall (P < 0.001) survival. High expression of αvß3 was linked to an advanced surgical stage (P = 0.028), a poor response to chemotherapy (P = 0.002), and both poor disease-free survival (P < 0.001) and overall survival (P < 0.001). FN and αvß3 co-expression were associated with sex (P = 0.011), an advanced surgical stage (P = 0.013), and a poor response to chemotherapy (P = 0.002). Moreover, high expression of both proteins can serve as an independent prognostic value for reduced survival time in osteosarcoma patients. CONCLUSIONS: The results of this study suggest that FN and αvß3 expression is associated with an unfavorable clinical outcome of osteosarcoma, and these molecules may constitute attractive therapeutic targets for osteosarcoma treatment. To improve the survival of osteosarcoma patients, further investigations are required to clarify their prognostic values in a larger population.
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Neoplasias Óseas/patología , Fibronectinas/análisis , Integrina alfaVbeta3/análisis , Osteosarcoma/patología , Adulto , Anciano , Neoplasias Óseas/química , Neoplasias Óseas/mortalidad , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Osteosarcoma/química , Osteosarcoma/mortalidad , PronósticoRESUMEN
Many immunostimulants act as vaccine adjuvants via activation of the innate immune system, although in many cases it is unclear which specific molecules contribute to the stimulatory activity. QS-21 is a defined, highly purified, and soluble saponin adjuvant currently used in licensed and exploratory vaccines, including vaccines against malaria, cancer, and HIV-1. However, little is known about the mechanisms of cellular activation induced by QS-21. We observed QS-21 to elicit caspase-1-dependent IL-1ß and IL-18 release in antigen-presenting cells such as macrophages and dendritic cells when co-stimulated with the TLR4-agonist adjuvant monophosphoryl lipid A. Furthermore, our data suggest that the ASC-NLRP3 inflammasome is responsible for QS-21-induced IL-1ß/IL-18 release. At higher concentrations, QS-21 induced macrophage and dendritic cell death in a caspase-1-, ASC-, and NLRP3-independent manner, whereas the presence of cholesterol rescued cell viability. A nanoparticulate adjuvant that contains QS-21 as part of a heterogeneous mixture of saponins also induced IL-1ß in an NLRP3-dependent manner. Interestingly, despite the role NLRP3 plays for cellular activation in vitro, NLRP3-deficient mice immunized with HIV-1 gp120 and QS-21 showed significantly higher levels of Th1 and Th2 antigen-specific T cell responses and increased IgG1 and IgG2c compared with wild type controls. Thus, we have identified QS-21 as a nonparticulate single molecular saponin that activates the NLRP3 inflammasome, but this signaling pathway may contribute to decreased antigen-specific responses in vivo.
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Adyuvantes Inmunológicos/farmacología , Proteínas Portadoras/metabolismo , Células Dendríticas/efectos de los fármacos , Inmunidad Innata/efectos de los fármacos , Inflamasomas/efectos de los fármacos , Macrófagos/efectos de los fármacos , Saponinas/farmacología , Vacunas contra el SIDA/agonistas , Vacunas contra el SIDA/inmunología , Adyuvantes Inmunológicos/análisis , Adyuvantes Inmunológicos/química , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/inmunología , Proteínas Portadoras/genética , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Células Dendríticas/citología , Células Dendríticas/inmunología , Proteínas de Unión al GTP/genética , Proteínas de Unión al GTP/metabolismo , Proteína gp120 de Envoltorio del VIH/agonistas , Proteína gp120 de Envoltorio del VIH/inmunología , Inmunoglobulina G/análisis , Inmunoglobulina G/biosíntesis , Inflamasomas/inmunología , Inflamasomas/metabolismo , Lípido A/agonistas , Lípido A/análogos & derivados , Lípido A/farmacología , Macrófagos/citología , Macrófagos/inmunología , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína con Dominio Pirina 3 de la Familia NLR , Saponinas/análisis , Saponinas/química , Solubilidad , Células TH1/efectos de los fármacos , Células TH1/inmunología , Células TH1/metabolismo , Células Th2/efectos de los fármacos , Células Th2/inmunología , Células Th2/metabolismoRESUMEN
Salecan, a water-soluble extracellular ß-glucan produced by Agrobacterium sp. ZX09, has been reported to exhibit a wide range of biological effects. The aims of the present study were to investigate the protective effect of salecan against Concanavalin A (ConA)-induced hepatitis, a well-established animal model of immune-mediated liver injury, and to search for possible mechanisms. C57BL/6 mice were pretreated with salecan followed by ConA injection. Salecan treatment significantly reduced ConA-induced acute liver injury, and suppressed the expression and secretion of inflammatory cytokines including interferon (IFN)-γ, interleukin (IL)-6 and IL-1ß in ConA-induced liver injury model. The high expression levels of chemokines and adhesion molecules such as MIP-1α, MIP-1ß, ICAM-1, MCP-1 and RANTES in the liver induced by ConA were also down-regulated after salecan treatment. Salecan inhibited the infiltration and activation of inflammatory cells, especially T cells, in the liver induced by ConA. Moreover, salecan reversed the metabolic profiles of ConA-treated mice towards the control group by partly recovering the metabolic perturbations induced by ConA. Our results suggest the preventive and therapeutic potential of salecan in immune-mediated hepatitis.
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Enfermedad Hepática Inducida por Sustancias y Drogas/inmunología , Concanavalina A/toxicidad , Inmunidad Celular/fisiología , Metaboloma/fisiología , Linfocitos T/inmunología , beta-Glucanos/uso terapéutico , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Concanavalina A/antagonistas & inhibidores , Inmunidad Celular/efectos de los fármacos , Espectroscopía de Resonancia Magnética/métodos , Masculino , Metaboloma/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo , beta-Glucanos/farmacologíaRESUMEN
A number of pathogens cause host cell death upon infection, and Yersinia pestis, infamous for its role in large pandemics such as the "Black Death" in medieval Europe, induces considerable cytotoxicity. The rapid killing of macrophages induced by Y. pestis, dependent upon type III secretion system effector Yersinia outer protein J (YopJ), is minimally affected by the absence of caspase-1, caspase-11, Fas ligand, and TNF. Caspase-8 is known to mediate apoptotic death in response to infection with several viruses and to regulate programmed necrosis (necroptosis), but its role in bacterially induced cell death is poorly understood. Here we provide genetic evidence for a receptor-interacting protein (RIP) kinase-caspase-8-dependent macrophage apoptotic death pathway after infection with Y. pestis, influenced by Toll-like receptor 4-TIR-domain-containing adapter-inducing interferon-ß (TLR4-TRIF). Interestingly, macrophages lacking either RIP1, or caspase-8 and RIP3, also had reduced infection-induced production of IL-1ß, IL-18, TNF, and IL-6; impaired activation of the transcription factor NF-κB; and greatly compromised caspase-1 processing. Cleavage of the proform of caspase-1 is associated with triggering inflammasome activity, which leads to the maturation of IL-1ß and IL-18, cytokines important to host responses against Y. pestis and many other infectious agents. Our results identify a RIP1-caspase-8/RIP3-dependent caspase-1 activation pathway after Y. pestis challenge. Mice defective in caspase-8 and RIP3 were also highly susceptible to infection and displayed reduced proinflammatory cytokines and myeloid cell death. We propose that caspase-8 and the RIP kinases are key regulators of macrophage cell death, NF-κB and inflammasome activation, and host resistance after Y. pestis infection.
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Caspasa 8/metabolismo , Muerte Celular , Inmunidad Innata , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Animales , Apoptosis , Proteínas Bacterianas/genética , Células de la Médula Ósea/citología , Citocinas/metabolismo , Macrófagos/metabolismo , Macrófagos/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , FN-kappa B/metabolismo , Yersiniosis/microbiología , Yersinia pestis/genéticaRESUMEN
Accumulating epidemiological evidence underscores the association between pervasive environmental factors and an increased risk of metabolic diseases. Environmental chemicals, recognized disruptors of endocrine and metabolic processes, may contribute to the global prevalence of metabolic disorders, including obesity. Acetyl tributyl citrate (ATHC), categorized as a citric acid ester plasticizer, serves as a substitute for di-(2-ethylhexyl) phthalate (DEHP) in various everyday products. Despite its widespread use and the increasing risk of exposure in humans and animals due to its high leakage rates, information regarding the safety of exposure to environmentally relevant doses of ATHC remains limited. This study aimed to investigate the potential impact of ATHC exposure on metabolic homeostasis. Both in vivo and in vitro exposure models were used to characterize the effects induced by ATHC exposure. C57BL/6 J male mice were subjected to a diet containing ATHC for 12 weeks, and metabolism-related parameters were monitored and analyzed throughout and after the exposure period. Results indicated that sub-chronic dietary exposure to ATHC induced an increase in body fat percentage, elevated serum lipid levels, and increased lipid content in the liver tissue of mice. Furthermore, the effect of ATHC exposure on murine hepatocytes were examined and results indicated that ATHC significantly augmented lipid levels in AML12 hepatocytes, disrupting energy homeostasis and altering the expression of genes associated with fatty acid synthesis, uptake, oxidation, and secretion pathways. Conclusively, both in vivo and in vitro results suggest that exposure to low levels of ATHC may be linked to an elevated risk of obesity and fatty liver in mice. The potential implications of ATHC on human health warrant comprehensive evaluation in future studies.
RESUMEN
Acute respiratory distress syndrome (ARDS) is characterized by lung tissue oedema and inflammatory cell infiltration, with limited therapeutic interventions available. Receptor-interacting protein kinase 1 (RIPK1), a critical regulator of cell death and inflammation implicated in many diseases, is not fully understood in the context of ARDS. In this study, we employed RIP1 kinase-inactivated (Rip1K45A/K45A) mice and two distinct RIPK1 inhibitors to investigate the contributions of RIP1 kinase activity in lipopolysaccharide (LPS)-induced ARDS pathology. Our results indicated that RIPK1 kinase inactivation, achieved through both genetic and chemical approaches, significantly attenuated LPS-induced ARDS pathology, as demonstrated by reduced polymorphonuclear neutrophil percentage (PMN%) in alveolar lavage fluid, expression of inflammatory and fibrosis-related factors in lung tissues, as well as histological examination. Results by tunnel staining and qRT-PCR analysis indicated that RIPK1 kinase activity played a role in regulating cell apoptosis and inflammation induced by LPS administration in lung tissue. In summary, employing both pharmacological and genetic approaches, this study demonstrated that targeted RIPK1 kinase inactivation attenuates the pathological phenotype induced by LPS inhalation in an ARDS mouse model. This study enhances our understanding of the therapeutic potential of RIPK1 kinase modulation in ARDS, providing insights for the pathogenesis of ARDS.
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Lipopolisacáridos , Inhibidores de Proteínas Quinasas , Proteína Serina-Treonina Quinasas de Interacción con Receptores , Síndrome de Dificultad Respiratoria , Animales , Humanos , Masculino , Ratones , Apoptosis/efectos de los fármacos , Modelos Animales de Enfermedad , Pulmón/patología , Pulmón/efectos de los fármacos , Pulmón/inmunología , Ratones Endogámicos C57BL , Neutrófilos/inmunología , Neutrófilos/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética , Síndrome de Dificultad Respiratoria/inducido químicamente , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Síndrome de Dificultad Respiratoria/inmunologíaRESUMEN
OBJECTIVE: To study the reversal effect of NVP-BEZ235 on doxorubicin resistance in Burkitt lymphoma RAJI cell line. METHODS: The doxorubicin-resistant cell line was induced by treating RAJI cells with a concentration gradient of doxorubicin. The levels of Pgp, p-AKT, and p-mTOR in cells were detected by Western blot. Cell viability was detected by MTT assay. IC50 was computed by SPSS. RESULTS: The doxorubicin-resistant Burkitt lymphoma cell line, RAJI/DOX, was established successfully. The expression of Pgp and the phosphorylation levels of AKT and mTOR in RAJI/DOX cell line were both higher than those in RAJI cell line. NVP-BEZ235 downregulated the phosphorylation levels of AKT and mTOR in RAJI/DOX cell line. NVP-BEZ235 inhibited the proliferation of RAJI/DOX cell line, and the effect was obvious when it was cooperated with doxorubicin. CONCLUSION: The constitutive activation of PI3K/AKT/mTOR pathway of RAJI/DOX cell line was more serious than RAJI cell line. NVP-BEZ235 reversed doxorubicin resistance of RAJI/DOX cell line by inhibiting the PI3K/AKT/mTOR signal pathway.
Asunto(s)
Linfoma de Burkitt , Proliferación Celular , Doxorrubicina , Resistencia a Antineoplásicos , Imidazoles , Proteínas Proto-Oncogénicas c-akt , Quinolinas , Serina-Treonina Quinasas TOR , Humanos , Doxorrubicina/farmacología , Línea Celular Tumoral , Proteínas Proto-Oncogénicas c-akt/metabolismo , Quinolinas/farmacología , Serina-Treonina Quinasas TOR/metabolismo , Proliferación Celular/efectos de los fármacos , Imidazoles/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal , Supervivencia Celular/efectos de los fármacos , FosforilaciónRESUMEN
The global incidence of obesity and non-alcoholic fatty liver disease (NAFLD) is rising rapidly in recent years. Environmental factors including usage of plastics and exposure to chemicals have been proposed as important contributors to the obesity pandemic. Acetyl tributyl citrate (ATBC) is a non-phthalate plasticizer widely used in food packaging, personal care products, medical devices and children's toys etc. Due to its high leakage rate from plastics, exposure risk of ATBC keeps increasing. Although there are some studies investigating the safety of ATBC on human health, these studies mainly focused on high dosages and information regarding ATBC safety at environmental-relevant low levels is still limited. In this study, we aimed to evaluate the safety of subchronic exposure to environmentally-relevant concentrations of ATBC. C57BL/6J mice were orally exposed to ATBC for 6 or 14 weeks. Results indicated that ATBC exposure increased the body weight gain, the body fat content and the size of adipocytes, induced liver steatosis in mice. Consistent with in vivo effects, ATBC treatment increased the intracellular lipid accumulation in vitro hepatocytes. Transcriptome sequencing, qRT-PCR analysis and western blotting revealed that ATBC exposure affected the expression of genes involved in de novo lipogenesis and lipid uptake. Therefore, based on our subchronic and in vitro results, it suggested that ATBC might be a potential environmental obesogen with metabolism-disturbing and fatty liver-inducing risk, and its application in many consumer products should be carefully re-evaluated.
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Hígado Graso , Plastificantes , Niño , Ratones , Humanos , Animales , Plastificantes/toxicidad , Plastificantes/análisis , Ratones Endogámicos C57BL , Plásticos , Hígado Graso/inducido químicamente , Lípidos , HígadoRESUMEN
Framework-structured weak ferromagnets are new rising stars in molecule-based magnetic materials. The framework structures are powerful carriers for long-range ordering of spins. And weak ferromagnetism due to spin canting is an effective approach for magnets because of its frequent occurrence and desired spontaneous magnetization as long as the canting angle γ is large enough. In this critical review, we provide an overview of the various framework-structured weak ferromagnets based on different grades of ligands (from mono-atom to three-atom-like ligands). Particular emphasis is given to the relationships between structural features and the properties, rational employment of the ligands, and weak ferromagnetic strategies for molecule-based magnets with exciting properties and applications (273 references).
RESUMEN
BACKGROUND: Gestational trophoblastic diseases (GTDs) are characterized by vascular abnormalities of the trophoblast, but their pathogenesis is unknown. Angiogenin (ANG) and matrix metalloproteinase (MMP)-2, which are molecules implicated in the angiogenic process, may play some role in this process. MATERIAL AND METHODS: We determined ANG and MMP-2 in the placental tissues of 26 patients who had a benign mole (BM), 12 patients with gestational trophoblast neoplasia (GTN) (1 invasive hydatidiform mole, 10 choriocarcinomas, and 1 placental-site trophoblastic tumor), and 28 normal chorionic villi (NCV) subjects using immunohistochemistry staining. We obtained the serum samples from 20 patients with GTDs and 20 early pregnant women and evaluated them by the enzyme linked immunosorbent assay. RESULTS: ANG expression in GTN (66.7%) and BM (100%) samples were both significantly higher (strong/intermediate staining) than in NCV (60.7%) samples (Pâ<â.001). Similarly, the immunoreactivities of MMP-2 in the GTN (66.7%) and BM (80.8%) samples were significantly elevated compared to that of the NCV (57.1%) samples (Pâ<â.001). The levels of ANG and MMP-2 in the maternal serum of the GTN group were both significantly higher than those of the control group (Pâ<â.001). ANG and MMP-2 expressions were associated with gestation age, clinical stage, and FIGO stage. A positive correlation between ANG and MMP-2 expression was observed (rsâ=â0.725; Pâ<â.01). CONCLUSION: ANG and MMP-2 levels were significantly elevated in the placental tissues and maternal serum from patients with GTDs. Further studies with more patients may clarify the vascular abnormalities in GTDs and determine potential biomarkers in the differential diagnosis of GTDs.
Asunto(s)
Enfermedad Trofoblástica Gestacional , Mola Hidatiforme , Metaloproteinasa 2 de la Matriz/metabolismo , Ribonucleasa Pancreática/metabolismo , Neoplasias Uterinas , Biomarcadores , Diagnóstico Diferencial , Femenino , Enfermedad Trofoblástica Gestacional/diagnóstico , Humanos , Mola Hidatiforme/diagnóstico , Placenta/metabolismo , Embarazo , Neoplasias Uterinas/diagnósticoRESUMEN
SCOPE: Clostridium butyricum (CB) exerts beneficial actions in several disorders. However, the impact and molecular cues of CB in fat metabolism remain elusive. This study demonstrates the CB inhibition of fat deposition by increasing the relative number of adipose tissue-resident Treg cells (aTregs). METHODS AND RESULTS: CB is administered orally to wild type (WT) mice fed with chow diet, which decrease fat deposition and adipogenic gene expression, associating with elevated serum levels of butyrate. Sodium butyrate (SB) feeding mimics the CB suppression of fat accumulation. Of note, the frequency of aTregs in both the CB and SB treatments, analyzed by flow cytometry, is markedly increased, accompanied by activated Wnt10b expression in white adipose tissues. However, CB and SB fail to inhibit fat deposition in Wnt10b-KO mice. Intriguingly, CB and SB are able to alleviate the obesity, fatty liver, and glucose abnormalities in high fat diet (HFD)-fed WT mice. CONCLUSIONS: These findings suggest that CB, through its metabolite butyrate, inhibits fat deposition via potentiating aTreg cell generation, and support the option of CB and SB for therapeutic interventions in obesity and related disorders.