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1.
Toxicol Appl Pharmacol ; 482: 116788, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38086441

RESUMO

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.


Assuntos
Citratos , Lipogênese , Plastificantes , Masculino , Camundongos , Humanos , Animais , Plastificantes/toxicidade , Camundongos Endogâmicos C57BL , Obesidade/induzido quimicamente , Obesidade/metabolismo , Lipídeos , Fígado , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo
2.
Environ Toxicol ; 38(6): 1395-1404, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36896678

RESUMO

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.


Assuntos
PPAR gama , Plastificantes , Camundongos , Humanos , Animais , Plastificantes/toxicidade , PPAR gama/metabolismo , Metabolismo dos Lipídeos , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Adipatos
3.
J Biol Chem ; 297(1): 100846, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34058194

RESUMO

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.


Assuntos
Diabetes Mellitus Tipo 2/genética , Proteína Forkhead Box O1/genética , Hiperglicemia/genética , Transcrição Gênica/genética , Nucleotídeos de Adenina/sangue , Animais , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/patologia , Regulação da Expressão Gênica/genética , Gluconeogênese/genética , Glucose/metabolismo , Humanos , Hiperglicemia/sangue , Hiperglicemia/patologia , Insulina/genética , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Endogâmicos NOD
4.
Bioorg Med Chem ; 59: 116686, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35228069

RESUMO

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.


Assuntos
Compostos Aza , Inibidores de Proteínas Quinases , Proteína Serina-Treonina Quinases de Interação com Receptores , Compostos de Espiro , Humanos , Apoptose , Compostos Aza/química , Compostos Aza/farmacologia , Necroptose , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/farmacologia , Compostos de Espiro/química , Compostos de Espiro/farmacologia
5.
Immunity ; 37(1): 96-107, 2012 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-22840842

RESUMO

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.


Assuntos
Inflamassomos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peste/imunologia , Peste/metabolismo , Yersinia pestis/imunologia , Animais , Inflamassomos/imunologia , Interferon gama/biossíntese , Interleucina-18/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peste/mortalidade , Transdução de Sinais
6.
J Orthop Sci ; 26(6): 1100-1106, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32972820

RESUMO

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.


Assuntos
Osteossarcoma , Humanos , Imuno-Histoquímica , Prognóstico , Proto-Oncogene Mas , Receptores Proteína Tirosina Quinases
7.
J Med Virol ; 92(10): 1995-2003, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32330299

RESUMO

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.


Assuntos
Infecções Assintomáticas/epidemiologia , COVID-19/epidemiologia , Pandemias/estatística & dados numéricos , China/epidemiologia , Surtos de Doenças , Humanos , Modelos Teóricos , Pneumonia Viral/epidemiologia , Saúde Pública/estatística & dados numéricos , Quarentena/métodos , SARS-CoV-2/patogenicidade , Isolamento Social
8.
Diabetologia ; 62(11): 2106-2117, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31410531

RESUMO

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.


Assuntos
Adenina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Fígado/metabolismo , Nucleotídeos/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Trifosfato de Adenosina/metabolismo , Adulto , Animais , Estudos de Casos e Controles , Membrana Celular/metabolismo , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Feminino , Hepatócitos/metabolismo , Homeostase , Humanos , Concentração de Íons de Hidrogênio , Hiperglicemia/metabolismo , Resistência à Insulina , Cinética , Espectroscopia de Ressonância Magnética , Masculino , Metformina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade
9.
Scand J Clin Lab Invest ; 79(8): 601-612, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31663373

RESUMO

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.


Assuntos
Receptores ErbB/genética , Amplificação de Genes , Osteossarcoma/genética , Osteossarcoma/patologia , Adolescente , Adulto , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Resultado do Tratamento , Adulto Jovem
10.
World J Surg Oncol ; 17(1): 23, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30691475

RESUMO

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.


Assuntos
Neoplasias Ósseas/patologia , Fibronectinas/análise , Integrina alfaVbeta3/análise , Osteossarcoma/patologia , Adulto , Idoso , Neoplasias Ósseas/química , Neoplasias Ósseas/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Osteossarcoma/química , Osteossarcoma/mortalidade , Prognóstico
11.
J Biol Chem ; 291(3): 1123-36, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26555265

RESUMO

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.


Assuntos
Adjuvantes Imunológicos/farmacologia , Proteínas de Transporte/metabolismo , Células Dendríticas/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Inflamassomos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Saponinas/farmacologia , Vacinas contra a AIDS/agonistas , Vacinas contra a AIDS/imunologia , Adjuvantes Imunológicos/análise , Adjuvantes Imunológicos/química , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/imunologia , Proteínas de Transporte/genética , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células Dendríticas/citologia , Células Dendríticas/imunologia , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Proteína gp120 do Envelope de HIV/agonistas , Proteína gp120 do Envelope de HIV/imunologia , Imunoglobulina G/análise , Imunoglobulina G/biossíntese , Inflamassomos/imunologia , Inflamassomos/metabolismo , Lipídeo A/agonistas , Lipídeo A/análogos & derivados , Lipídeo A/farmacologia , Macrófagos/citologia , Macrófagos/imunologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR , Saponinas/análise , Saponinas/química , Solubilidade , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/metabolismo , Células Th2/efeitos dos fármacos , Células Th2/imunologia , Células Th2/metabolismo
12.
Toxicol Appl Pharmacol ; 317: 63-72, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28109817

RESUMO

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.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/imunologia , Concanavalina A/toxicidade , Imunidade Celular/fisiologia , Metaboloma/fisiologia , Linfócitos T/imunologia , beta-Glucanas/uso terapêutico , Animais , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Concanavalina A/antagonistas & inibidores , Imunidade Celular/efeitos dos fármacos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Metaboloma/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , beta-Glucanas/farmacologia
13.
Proc Natl Acad Sci U S A ; 111(20): 7391-6, 2014 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-24799678

RESUMO

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.


Assuntos
Caspase 8/metabolismo , Morte Celular , Imunidade Inata , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Animais , Apoptose , Proteínas de Bactérias/genética , Células da Medula Óssea/citologia , Citocinas/metabolismo , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Yersiniose/microbiologia , Yersinia pestis/genética
14.
Int Immunopharmacol ; 133: 112060, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38652970

RESUMO

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.


Assuntos
Lipopolissacarídeos , Inibidores de Proteínas Quinases , Proteína Serina-Treonina Quinases de Interação com Receptores , Síndrome do Desconforto Respiratório , Animais , Humanos , Masculino , Camundongos , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Pulmão/patologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Camundongos Endogâmicos C57BL , Neutrófilos/imunologia , Neutrófilos/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/imunologia
15.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(2): 476-482, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-38660855

RESUMO

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.


Assuntos
Linfoma de Burkitt , Proliferação de Células , Doxorrubicina , Resistencia a Medicamentos Antineoplásicos , Imidazóis , Proteínas Proto-Oncogênicas c-akt , Quinolinas , Serina-Treonina Quinases TOR , Humanos , Doxorrubicina/farmacologia , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinolinas/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Proliferação de Células/efeitos dos fármacos , Imidazóis/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Sobrevivência Celular/efeitos dos fármacos , Fosforilação
16.
J Hazard Mater ; 445: 130548, 2023 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-37055963

RESUMO

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.


Assuntos
Fígado Gorduroso , Plastificantes , Criança , Camundongos , Humanos , Animais , Plastificantes/toxicidade , Plastificantes/análise , Camundongos Endogâmicos C57BL , Plásticos , Fígado Gorduroso/induzido quimicamente , Lipídeos , Fígado
17.
Chem Soc Rev ; 40(6): 3157-81, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21283846

RESUMO

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).

18.
Medicine (Baltimore) ; 101(5): e28768, 2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35119039

RESUMO

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 (P < .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 (P < .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 (P < .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 (rs = 0.725; P < .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.


Assuntos
Doença Trofoblástica Gestacional , Mola Hidatiforme , Metaloproteinase 2 da Matriz/metabolismo , Ribonuclease Pancreático/metabolismo , Neoplasias Uterinas , Biomarcadores , Diagnóstico Diferencial , Feminino , Doença Trofoblástica Gestacional/diagnóstico , Humanos , Mola Hidatiforme/diagnóstico , Placenta/metabolismo , Gravidez , Neoplasias Uterinas/diagnóstico
19.
Mol Nutr Food Res ; 66(12): e2100884, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35426245

RESUMO

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.


Assuntos
Clostridium butyricum , Tecido Adiposo/metabolismo , Animais , Butiratos/metabolismo , Dieta Hiperlipídica/efeitos adversos , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Linfócitos T Reguladores/metabolismo
20.
Environ Pollut ; 271: 116331, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33383419

RESUMO

Tributyltin (TBT), a bioaccumulative and persistent environmental pollutant, has been proposed as a metabolism disruptor and obesogen through targeting peroxisome proliferator-activated receptor gamma (PPARγ) receptor pathway. However, it remains unknown whether this biological effect occurs in macrophage, a cell type which cooperates closely with hepatocytes and adipocytes to regulate lipid metabolism. This study for the first time investigated the effect of TBT on PPARγ pathway in macrophages. Our results indicated that nanomolar levels of TBT was able to strongly activate PPARγ in human macrophages. TBT treatment also markedly increased the intracellular lipid accumulation, and enhanced the expression of lipid metabolism-related genes in macrophages, while these effects were all significantly down-regulated in PPARγ-deficient macrophages, confirming the involvement of PPARγ in TBT-induced lipogenesis. Next, a mouse model that C57BL/6 mice were orally exposed to TBT with the doses (250 and 500 µg/kg body weight) lower than NOAEL (no observed adverse effect level) was used to further investigate the in vivo mechanisms. And the in vivo results were consistent with cellular assays, confirming the induction of PPARγ and the increased expression of lipogenesis-regulating and lipid metabolism-related genes by TBT in vivo. In conclusion, this study not only provided the first evidence that TBT stimulated lipogenesis, activated PPARγ and related genes in human macrophages, but also provided insight into the mechanism of TBT-induced metabolism disturbance and obesity through targeting PPARγ via both in vitro cellular assays and in vivo animal models.


Assuntos
Lipogênese , PPAR gama , Animais , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , PPAR gama/genética , PPAR gama/metabolismo , Compostos de Trialquitina
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