RESUMEN
OBJECTIVES: Colitis is a global disease usually accompanied by intestinal epithelial damage and intestinal inflammation, and an increasing number of studies have found natural products to be highly effective in treating colitis. Anemoside B4 (AB4), an abundant saponin isolated from Pulsatilla chinensis (Bunge), which was found to have strong anti-inflammatory activity. However, the exact molecular mechanisms and direct targets of AB4 in the treatment of colitis remain to be discovered. METHODS: The anti-inflammatory activities of AB4 were verified in LPS-induced cell models and 2, 4, 6-trinitrobenzene sulfonic (TNBS) or dextran sulfate sodium (DSS)-induced colitis mice and rat models. The molecular target of AB4 was identified by affinity chromatography analysis using chemical probes derived from AB4. Experiments including proteomics, molecular docking, biotin pull-down, surface plasmon resonance (SPR), and cellular thermal shift assay (CETSA) were used to confirm the binding of AB4 to its molecular target. Overexpression of pyruvate carboxylase (PC) and PC agonist were used to study the effects of PC on the anti-inflammatory and metabolic regulation of AB4 in vitro and in vivo. RESULTS: AB4 not only significantly inhibited LPS-induced NF-κB activation and increased ROS levels in THP-1 cells, but also suppressed TNBS/DSS-induced colonic inflammation in mice and rats. The molecular target of AB4 was identified as PC, a key enzyme related to fatty acid, amino acid and tricarboxylic acid (TCA) cycle. We next demonstrated that AB4 specifically bound to the His879 site of PC and altered the protein's spatial conformation, thereby affecting the enzymatic activity of PC. LPS activated NF-κB pathway and increased PC activity, which caused metabolic reprogramming, while AB4 reversed this phenomenon by inhibiting the PC activity. In vivo studies showed that diisopropylamine dichloroacetate (DADA), a PC agonist, eliminated the therapeutic effects of AB4 by changing the metabolic rearrangement of intestinal tissues in colitis mice. CONCLUSION: We identified PC as a direct cellular target of AB4 in the modulation of inflammation, especially colitis. Moreover, PC/pyruvate metabolism/NF-κB is crucial for LPS-driven inflammation and oxidative stress. These findings shed more light on the possibilities of PC as a potential new target for treating colitis.
Asunto(s)
Colitis , Saponinas , Ratas , Ratones , Animales , Piruvato Carboxilasa/metabolismo , FN-kappa B/metabolismo , Lipopolisacáridos/farmacología , Simulación del Acoplamiento Molecular , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/metabolismo , Inflamación/metabolismo , Saponinas/farmacología , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Macrófagos/metabolismo , Sulfato de Dextran/efectos adversos , Sulfato de Dextran/metabolismo , Ratones Endogámicos C57BL , Modelos Animales de EnfermedadRESUMEN
The microbial community compositions of a chemostat enriched in a thermophilic (55 °C) mixed culture fermentation (MCF) for hydrogen production under different operational conditions were revealed in this work by integrating denaturing gradient gel electrophoresis (DGGE), Illumina Miseq high-throughput sequencing, and 16S rRNA clone library sequencing. The results showed that the community structure of the enriched cultures was relatively simple. Clones close to the genera of Thermoanaerobacter and/or Bacillus mainly dominated the bacteria. And homoacetogens and archaea were washed out and not detected even by Illumina Miseq high-throughput sequencing which supported the benefit for hydrogen production. On the other hand, the results revealed that the metabolic shift was clearly associated with the change of dominated bacterial groups. The effects of hydrogen partial pressure (PH2) and pH from 4.0 to 5.5 on the microbial compositions were not notable and Thermoanaerobacter was dominant, thus, the metabolites were also not changed. While Bacillus, Thermoanaerobacter and Propionispora hippei dominated the bacteria communities at neutral pH, or Bacillus and Thermoanaerobacter dominated at high influent glucose concentrations, consequently the main metabolites shifted to acetate, ethanol, propionate, or lactate. Thereby, the effect of microbial composition on the metabolite distribution and shift shall be considered when modeling thermophilic MCF in the future.
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Archaea/aislamiento & purificación , Bacterias/aislamiento & purificación , Reactores Biológicos/microbiología , Archaea/clasificación , Archaea/genética , Archaea/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Etanol/metabolismo , Fermentación , Hidrógeno/metabolismo , Concentración de Iones de Hidrógeno , Ácido Láctico/metabolismo , Microbiota , Datos de Secuencia Molecular , FilogeniaRESUMEN
BACKGROUND: Gut barrier failure caused by endotoxemia is a life-threatening problem. The present study aimed to determine whether any specific intestinal site is highly correlated with gut barrier failure, and whether recombinant human growth hormone (rhGH) can ameliorate gut barrier failure in a rat model of endotoxemia. METHODS: Enterostomy tubes were surgically placed in adult male Sprague-Dawley rats three days before induction of endotoxemia by lipopolysaccharide (LPS) injection. Controls received no LPS. Rats were then randomly assigned to receive subcutaneous injections of rhGH (experimental, n = 30) or 0.9 % saline (control, n = 15) at 24, 48, or 72 h after LPS injection. Escherichia coli labeled with green fluorescent protein (GFP) were injected into the intestinal segment of all rats through the enterostomy tubes. The number of GFP-labeled E. coli detected in mesenteric lymph nodes was examined after 96 h. Apoptosis and proliferation rates of intestinal epithelial cells, and intestinal permeability were measured. RESULTS: Endotoxemia led to high mortality, compared with the control group, and rhGH treatment did not improve survival. Intestinal permeability, reflected by translocation rates of GFP-labeled E. coli, and apoptosis rates in the LPS-induced endotoxemia group were higher than those in the non-endotoxemia control group, and the endotoxemia ileum group had the highest rates of both bacterial translocation and apoptosis. The LPS+GH group had less bacterial translocation and apoptosis than the LPS-induced endotoxemia group. In contrast, the proliferation rates were lower in the LPS group compared to the LPS+GH group. CONCLUSIONS: Endotoxemia can induce gut barrier failure in rats, and the ileum is the site of greatest risk. The GH can reduce the incidence of endotoxemia-induced gut barrier failure, but not the associated mortality.
Asunto(s)
Endotoxemia/tratamiento farmacológico , Infecciones por Escherichia coli/tratamiento farmacológico , Hormona de Crecimiento Humana/uso terapéutico , Intestinos/efectos de los fármacos , Animales , Apoptosis , Traslocación Bacteriana , Endotoxemia/metabolismo , Endotoxemia/microbiología , Endotoxemia/patología , Escherichia coli/fisiología , Infecciones por Escherichia coli/metabolismo , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/patología , Hormona de Crecimiento Humana/farmacología , Mucosa Intestinal/metabolismo , Intestinos/microbiología , Intestinos/patología , Lipopolisacáridos , Ganglios Linfáticos/microbiología , Masculino , Permeabilidad/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/farmacología , Proteínas Recombinantes/uso terapéuticoRESUMEN
Sarglanoids A-F, six new sesquiterpenoids belonging to eudesmane (1-5) and eremophilane (6) types, were isolated from the leaves of Sarcandra glabra, a famous traditional Chinese medicine (TCM). Their structures including absolute configurations were elucidated through extensive spectroscopic analysis and electronic circular dichroism (ECD) calculations. Compounds 1-2 were rare N-containing eudesmane-type sesquiterpenoids. Compound 3 exhibited inhibitory activity against nitric oxide (NO) production in lipopolysaccharides (LPS)-induced RAW 264.7 cells with IC50 values at 20.00 ± 1.30 µmol·L-1. These findings provide scientific evidence for sesquiterpenoids as the material foundation of S. glabra.
Asunto(s)
Sesquiterpenos , Estructura Molecular , Hojas de la Planta , Sesquiterpenos Policíclicos , Semillas , Sesquiterpenos/química , Sesquiterpenos/farmacologíaRESUMEN
BACKGROUND: As the Diagnostic and Statistical Manual of Mental Disorders fifth version (DSM-5) was published, the Kiddie-Schedule for Affective Disorders and Schizophrenia-Present and Lifetime version (K-SADS-PL) was modified to adapt the new version (K-SADS-PL DSM-5). We translated it to Chinese (K-SADS-PL-C DSM-5) and described its reliability and validity. METHODS: A total of 154 groups of 6 to 18-year-old children and their guardians were included. Trained interviewers interviewed subjects using the K-SADS-PL-C DSM-5. Interrater reliability was assessed by audio recording. Parent-reported scales, like child behavior checklist (CBCL), the Chinese version of Swan-son Nolan and Pelham, version IV scale-parent form (SNAP-IV), social responsiveness scale (SRS-1), and children-reported scales like depression self-rating scale for children (DSRSC) and the screen for child anxiety related emotional disorders (SCARED) were used to examine the validity of depressive disorder, ADHD, ASD, and ODD. RESULTS: The K-SADS-PL-C DSM-5 had fair to excellent interrater (0.537-1.000) and test-retest (0.468-0.885) reliability of affective disorder and neurodevelopment disorder. The convergent validity of affective disorder and neurodevelopment disorder was good, and their divergent validity was acceptable. LIMITATIONS: i) Clinical questionnaires were insensitive in classifying disorders and had limitations in derived diagnoses. ii) Samples only came from clinical environment, iii) covered limited disease species, and iv) were small. CONCLUSION: The K-SADS-PL-C DSM-5 can support reliable and valid diagnoses for children with affect, neurodevelopmental, and behavioral disorders in China.
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Esquizofrenia , Adolescente , Niño , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Humanos , Trastornos del Humor/diagnóstico , Trastornos del Humor/psicología , Escalas de Valoración Psiquiátrica , Reproducibilidad de los Resultados , Esquizofrenia/diagnósticoRESUMEN
Buxrugulosides A-E, four lignan glycosides (1-4) and a protocatechuate derivative (5) featuring a rare (N, N-diethyl)methyl amino group at aromatic rings, were obtained from the aerial parts of Buxus rugulosa, which is famous for treating coronary heart disease. Their structures including absolute configurations were elucidated by HRMS, 1D and 2D NMR, and by comparing their CD data with previous reports. Compound 1 was a rare sesquilignan, and all of these compounds were the first example of lignans with (N, N-diethyl)methyl amino group.
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Buxus , Lignanos , Glicósidos , Estructura Molecular , Extractos VegetalesRESUMEN
Vernoramyosides A-F (1-6), six new Δ7,9(11) stigmastane-type steroid saponins, along with four known analogues (7-10) were isolated from the leaves of Vernonia amygdalina Delile (Compositae). Their structures were determined by the combination of NMR, ECD and HR-ESI-MS data. These compounds all possessed highly oxidized side chain and a γ-lactam or α,ß-unsaturated five-membered lactone ring. All isolates were screened for their activities in reversing resistance in MCF/DOX cells.
Asunto(s)
Saponinas/farmacología , Esteroides/farmacología , Vernonia/química , China , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Humanos , Células MCF-7 , Estructura Molecular , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Hojas de la Planta/química , Saponinas/aislamiento & purificación , Esteroides/aislamiento & purificaciónRESUMEN
BACKGROUND: Acute mesenteric venous thrombosis (AMVT) can cause a poor prognosis. Prompt transcatheter thrombolysis (TT) can achieve early mesenteric revascularization. However, irreversible intestinal ischemia still occurs and the mechanism is still unclear. AIM: To evaluate the clinical outcomes of and to identify predictive factors for irreversible intestinal ischemia requiring surgical resection in AMVT patients treated by TT. METHODS: The records of consecutive patients with AMVT treated by TT from January 2010 to October 2017 were retrospectively analyzed. We compared patients who required resection of irreversible intestinal ischemia to patients who did not require. RESULTS: Among 58 patients, prompt TT was carried out 28.5 h after admission. A total of 42 (72.4%) patients underwent arteriovenous combined thrombolysis, and 16 (27.6%) underwent arterial thrombolysis alone. The overall 30-d mortality rate was 8.6%. Irreversible intestinal ischemia was indicated in 32 (55.2%) patients, who had a higher 30-d mortality and a longer in-hospital stay than patients without resection. The significant independent predictors of irreversible intestinal ischemia were Acute Physiology and Chronic Health Evaluation (APACHE) II score (odds ratio = 2.368, 95% confidence interval: 1.047-5.357, P = 0.038) and leukocytosis (odds ratio = 2.058, 95% confidence interval: 1.085-3.903, P = 0.027). Using the receiver operating characteristic curve, the cutoff values of the APACHE II score and leukocytosis for predicting the onset of irreversible intestinal ischemia were calculated to be 8.5 and 12 × 109/L, respectively. CONCLUSION: Prompt TT could achieve a favorable outcome in AMVT patients. High APACHE II score and leukocytosis can significantly predict the occurrence of irreversible intestinal ischemia. Therefore, close monitoring of these factors may help with the early identification of patients with irreversible intestinal ischemia, in whom ultimately surgical resection is required, before the initiation of TT.
Asunto(s)
Isquemia Mesentérica , Enfermedad Aguda , Humanos , Isquemia Mesentérica/diagnóstico por imagen , Isquemia Mesentérica/cirugía , Curva ROC , Estudios Retrospectivos , Procedimientos Quirúrgicos VascularesRESUMEN
OBJECTIVE: To investigate the effects of nuclear factor kappa B (NF-kappaB) on insulin signaling in skeletal muscle cells of rat with sepsis. METHODS: SD rats were randomly divided into two groups: control group and sepsis group.Sepsis model was reproduced by cecal ligation and puncture in sepsis group. At 8, 16, 24, 48 and 72 h after operation, the gastrocnemius was harvested. Conventional HE staining was used to observe the morphology of skeletal muscle cells. IRS-1 protein and tyrosine phosphorylation of IRS-1 and Ser(307) phosphorylation of IRS-1 were detected by Western Blotting and immuno-precipitation. Activities of NF-kappaB in skeletal muscle cells were detected by electrophoretic mobility shift assay. RESULTS: Tyrosine phosphorylation of IRS-1 in sepsis group was significantly lower than in control group (P < 0.01), while Ser(307) phosphorylation of IRS-1 in sepsis group was significantly higher than in control group (P < 0.01). In sepsis group, NF-kappaB activity in skeletal muscle cells was significantly higher than in control group (P < 0.01). There was significant negative correlation between activity of NF-kappaB and tyrosine phosphorylation of IRS-1 (r = 0.972, P < 0.01). There was significant positive correlation between activities of NF-kappaB and Ser(307) phosphorylation of IRS-1 (r = 0.969, P < 0.01). CONCLUSIONS: There is no inflammatory cell infiltrate in skeletal muscle cells with sepsis. But the activity of NF-kappaB in skeletal muscle cells is obviously enhanced, and it is closely related with disorder of insulin signaling in skeletal muscle cells of rat with sepsis.
Asunto(s)
Insulina/metabolismo , Fibras Musculares Esqueléticas/metabolismo , FN-kappa B/fisiología , Sepsis/metabolismo , Animales , Modelos Animales de Enfermedad , Proteínas Sustrato del Receptor de Insulina/metabolismo , Masculino , Fibras Musculares Esqueléticas/patología , FN-kappa B/metabolismo , Fosforilación , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Sepsis/patología , Transducción de SeñalRESUMEN
OBJECTIVE: The omega-3 polyunsaturated fatty acids (PUFAs) play a key role as immune response modulators and suppressors of immunologic functions, such as lymphocyte proliferation, cytokine production, and cell surface molecular expression in T lymphocytes, monocytes, and natural killer cells. However, little is known about the effect of omega-3 PUFAs on dendritic cells (DCs). We studied the effect of omega-3 PUFAs on DCs and the related intracellular signal transduction pathway. METHODS: Dendritic cells were generated from human peripheral blood monocytes in the presence of granulocyte-macrophage colony-stimulating factors and interleukin (IL)-4 and treated with eicosapentaenoic acid (EPA), docosahexanoic acid (DHA), and stearic acid for 24 h. Lipopolysaccharide (LPS) was used for maturation of the DCs. The expressions of CD40, CD80, CD86, and human leukocyte antigen-DR (HLA-DR) were analyzed by flow cytometry; production of IL-12 and tumor necrosis factor-alpha were detected by reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay. The proliferative ability of allogeneic T cells stimulated by DCs was evaluated by tritiated thymidine ((3)H-TdR). Western blot analysis of p38 mitogen-activated protein kinase was conducted. RESULTS: The omega-3 PUFAs reduced expression levels of costimulatory molecules CD80 and CD86 and major histocompatibility complex HLA-DR. IL-12 and tumor necrosis factor-alpha levels decreased significantly in the EPA and DHA groups. EPA and DHA also significantly reduced the proliferative ability of allogeneic T cells stimulated by DCs. The omega-3 PUFAs significantly inhibited LPS-induced p38 phosphorylation. CONCLUSION: The omega-3 PUFAs may inhibit LPS-induced DC maturation and upregulate cytokine production. Impaired p38 mitogen-activated protein kinase activity is a potential critical intracellular signaling transduction mechanism.
Asunto(s)
Citocinas/biosíntesis , Células Dendríticas/enzimología , Ácidos Grasos Omega-3/farmacología , Transducción de Señal , Proteínas Quinasas p38 Activadas por Mitógenos/efectos de los fármacos , Western Blotting , Células Cultivadas , Células Dendríticas/fisiología , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Antígenos HLA-DR/metabolismo , Humanos , Lipopolisacáridos/farmacología , Complejo Mayor de Histocompatibilidad , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Linfocitos T/metabolismo , Linfocitos T/fisiología , Regulación hacia Arriba , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
BACKGROUND: Alemtuzumab has been used in organ transplantation and a variety of hematologic malignancies (especially for the treatment of B-cell chronic lymphocytic leukemia). However, serious infectious complications frequently occur after treatment. The reason for increased infections postalemtuzumab treatment is unknown at this stage. We explore the effect of alemtuzumab on intestinal intraepithelial lymphocytes (IELs) and intestinal barrier function in cynomolgus model to explain the reason of infection following alemtuzumab treatment. METHODS: Twelve male cynomolguses were randomly assigned to either a treatment or control group. The treatment group received alemtuzumab (3 mg/kg, intravenous injection) while the control group received the same volume of physiological saline. Intestinal IELs were isolated from the control group and the treatment group (on day 9, 35, and 70 after treatment) for counting and flow cytometric analysis. Moreover, intestinal permeability was monitored by enzymatic spectrophotometric technique and enzyme-linked immunosorbent assay. RESULTS: The numbers of IELs were decreased significantly on day 9 after treatment compared with the control group (0.35 ± 0.07 × 10 8 and 1.35 ± 0.09 × 10 8 , respectively; P < 0.05) and were not fully restored until day 70 after treatment. There were significant differences among four groups considering IELs subtypes. In addition, the proportion of apoptotic IELs after alemtuzumab treatment was significantly higher than in the control group (22.01 ± 3.67 and 6.01 ± 1.42, respectively; P < 0.05). Moreover, the concentration of D-lactate and endotoxin was also increased significantly on day 9 after treatment. CONCLUSIONS: Alemtuzumab treatment depletes lymphocytes in the peripheral blood and intestine of cynomolgus model. The induction of apoptosis is an important mechanism of lymphocyte depletion after alemtuzumab treatment. Notably, intestinal barrier function may be disrupted after alemtuzumab treatment.
Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Intestinos/citología , Linfocitos/efectos de los fármacos , Alemtuzumab , Animales , Apoptosis/efectos de los fármacos , Citometría de Flujo , Macaca fascicularis , Masculino , Microscopía Electrónica de TransmisiónRESUMEN
Strictosidine synthase (STR) is the key enzyme involved in early steps of biosynthesis of monoterpenoid indole alkaloids. STR catalyzes the condensation of tryptamine with secologanin into strictosidine. The gene encoding STR targeted to different subcellular compartments was transiently expressed in the tobacco leaves. In vitro STR enzymatic activity was measured by the depletion of tryptamine indicated by fluorescence. The results showed that the recombinant STR was effectively expressed as soluble protein in three subcellular compartments-chloroplast, vacuole and endoplasmic reticulum in the leaves of tobacco by Western blot analysis and STR enzymatic assay.
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Liasas de Carbono-Nitrógeno/genética , Nicotiana/genética , Hojas de la Planta/genética , Western Blotting , Liasas de Carbono-Nitrógeno/metabolismo , Cloroplastos/enzimología , Retículo Endoplásmico/enzimología , Hojas de la Planta/enzimología , Plantas Modificadas Genéticamente , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Nicotiana/enzimología , Transfección/métodos , Transformación Genética , Triptaminas/metabolismo , Vacuolas/enzimologíaRESUMEN
Immune dysfunction is a major cause of mortality in septic patients. Current evidence indicates an important role for dendritic cells (DCs) in the pathophysiology of immune dysfunction, and these cells are potential targets of immunomodulation therapies. In the present study, our aim was to enhance the resistance of endotoxemic mice to bacterial translocation and secondary infection and to improve the outcome of these infections using a combination therapy consisting of thymosin alpha1 and dexamethasone in a timely manner according to the changes of DCs' number. The effect of treatment with dexamethasone (DXM) and thymosin alpha1 (Tα1) on DCs was investigated by examining their number, MHCII and CD86 expression and their capacity to induce T cell activation. Endotoxemic mice were randomly divided into five treatment groups. The survival rates, the levels of TNF-α and IL-10, the occurrence of bacterial translocation, and the ability to clear secondary infections were determined. Additionally, the behavior of DCs over time was also evaluated. Tα1 induced significant increases in DC numbers in vivo, whereas DXM reduced cell numbers both in vitro and in vivo. However, neither drug induced significant changes in the capacity of DCs to induce T cell activation or their expression of MHCII or CD86. Among the five treatment groups, the mice treated with a combination of DXM and Tα1 had the highest survival rate; this increased survival was associated with a decrease in bacterial translocation to extra-intestinal organs and an enhanced ability to eradicate secondary infections by reversing the change in DC numbers during endotoxemia. Immunomodulatory therapy that combines Tα1 and DXM in a timely manner and was based on changes in DCs enhanced the resistance of endotoxemic mice to bacterial translocation and secondary infections, improving the outcome of the infection.
Asunto(s)
Células Dendríticas/efectos de los fármacos , Dexametasona/farmacología , Endotoxemia/tratamiento farmacológico , Infecciones por Escherichia coli/tratamiento farmacológico , Factores Inmunológicos/farmacología , Sepsis/tratamiento farmacológico , Timosina/análogos & derivados , Animales , Antígeno B7-2/sangre , Traslocación Bacteriana/efectos de los fármacos , Células Cultivadas , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Modelos Animales de Enfermedad , Quimioterapia Combinada , Endotoxemia/sangre , Endotoxemia/inmunología , Endotoxemia/microbiología , Infecciones por Escherichia coli/sangre , Infecciones por Escherichia coli/inmunología , Infecciones por Escherichia coli/microbiología , Femenino , Antígenos de Histocompatibilidad Clase II/sangre , Mediadores de Inflamación/sangre , Interleucina-10/sangre , Activación de Linfocitos/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Sepsis/sangre , Sepsis/inmunología , Sepsis/microbiología , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Linfocitos T/metabolismo , Timalfasina , Timosina/farmacología , Factores de Tiempo , Factor de Necrosis Tumoral alfa/sangreRESUMEN
Deregulation of the WNT signaling pathway is associated with the development and progression of breast cancer. ß-catenin mutations have been found to constitutively activate ß-catenin-T-cell factor (TCF) signaling in other types of cancer. ß-catenin acetylation regulates ß-catenin-TCF4 interaction in WNT signaling, but it remains unknown whether the acetylation of ß-catenin is involved in WNT-induced proliferation of breast cancer cells. In this study, a lower level of acetylated ß-catenin (K345) was observed in breast cancer tissues. WNT3A stimulated the downregulation of ß-catenin acetylation and promoted the proliferation of MCF7 cells. The K345Q mutation in ß-catenin inhibited WNT-induced cell growth and axin2/TCF7 upregulation in breast cancer cells. By contrast, K345R mutants could mimic deacetylated ß-catenin to generate the WNT-elicited phenotype. Additionally, the acetylation of ß-catenin may prime ß-catenin for phosphorylation. Further investigation revealed that the deacetylase HDAC6 was responsible for WNT-induced deacetylation of ß-catenin in breast cancer cells. In conclusion, the epigenetic modification of ß-catenin may be essential for WNT signaling in breast cancer progression, and blocking the occurrence of ß-catenin acetylation may provide a novel therapeutic approach for breast cancer.
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Neoplasias de la Mama/fisiopatología , Vía de Señalización Wnt , Proteína Wnt3A/metabolismo , beta Catenina/metabolismo , Acetilación , Proteína Axina/metabolismo , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Proliferación Celular , Regulación hacia Abajo , Femenino , Histona Desacetilasa 6 , Histona Desacetilasas/química , Histona Desacetilasas/genética , Histona Desacetilasas/metabolismo , Humanos , Células MCF-7 , Mutación , Fosforilación , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Factor 1 de Transcripción de Linfocitos T/metabolismo , Regulación hacia Arriba , beta Catenina/genéticaRESUMEN
Berberine hydrochloride (BBR), a plant alkaloid, has been used to treat intestinal inflammation or infection for years. Cyclooxygenase-2 (COX-2) is pro-inflammatory mediator and involved in the induction of gut inflammation. The expression of COX-2 in small bowel mucosa was determined and the mechanism by which BBR modulated COX-2 expression was explored in a rat model of endotoxemia induced by lipopolysaccharide (LPS). The results showed that without LPS stimulation COX-2 was constitutively expressed at low levels in control rats. LPS challenge rapidly induced COX-2 gene transcription resulting in high levels of inducible COX-2 expression in endotoxemic rats. BBR pre- and post-treatment had no marked effect on constitutive COX-2 expression but inhibited inducible COX-2 overexpression. LPS challenge increased the expression and phosphorylation of peroxisome proliferator-activated receptor gamma (PPARγ), p38 and activating transcription factor 2 and 3 (ATF2, ATF3), but the effects of LPS were inhibited by BBR treatment. GW9662 did not influence constitutive COX-2 expression but enhanced inducible COX-2 overproduction. Besides, GW9662 abolished the inhibitory effect of BBR on inducible COX-2, p38, ATF2, 3 expression and phosphorylation. Collectively, these results indicated that BBR gavage could attenuate the overexpression of inducible COX-2, not constitutive COX-2, in ileal mucosa during acute endotoxemia in part via activation of PPARγ pathway, which negatively interfered with p38/ATFs cascade.
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Berberina/farmacología , Inhibidores de la Ciclooxigenasa 2/farmacología , Ciclooxigenasa 2/metabolismo , Endotoxemia/metabolismo , Mucosa Intestinal/efectos de los fármacos , PPAR gamma/agonistas , Anilidas/farmacología , Animales , Ciclooxigenasa 2/genética , Modelos Animales de Enfermedad , Endotoxemia/inducido químicamente , Escherichia coli , Íleon/efectos de los fármacos , Íleon/metabolismo , Mucosa Intestinal/metabolismo , Lipopolisacáridos , Masculino , PPAR gamma/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-DawleyRESUMEN
The effect of berberine hydrochloride (BBR) on inducible cyclooxygenase-2 (COX-2) in small intestinal mucosa and related mechanisms was investigated in a rat model of acute endotoxemia. The results showed that lipopolysaccharide (LPS) increased COX-2 expression, whereas SB202190 and BBR curtailed it. LPS increased phosphorylation of mucosal p38 MAPK and ATF2 as well as production of ATF2, whereas BBR attenuated these effects. LPS upregulated mucosal peroxisome proliferator-activated receptor gamma (PPARγ), but BBR reduced this receptor. GW9662 aggravated LPS-induced and reversed BBR-attenuated COX-2 expression. The findings showed that BBR ameliorated COX-2 overexpression partially via modulation of p38 and PPARγ pathways during acute endotoxemia.
Asunto(s)
Antiinflamatorios/farmacología , Berberina/farmacología , Inhibidores de la Ciclooxigenasa 2/uso terapéutico , Ciclooxigenasa 2/metabolismo , Endotoxemia/tratamiento farmacológico , Mucosa Intestinal/efectos de los fármacos , Fitoterapia , Enfermedad Aguda , Anilidas , Animales , Coptis/química , Inhibidores de la Ciclooxigenasa 2/farmacología , Modelos Animales de Enfermedad , Endotoxemia/metabolismo , Inhibidores Enzimáticos/farmacología , Imidazoles/farmacología , Mucosa Intestinal/metabolismo , Intestino Delgado/efectos de los fármacos , Intestino Delgado/metabolismo , Lipopolisacáridos , Masculino , PPAR gamma/metabolismo , Fosforilación , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Piridinas/farmacología , Ratas , Ratas Sprague-Dawley , Rizoma , Regulación hacia Arriba , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
It is known that the loss of DC plays an important role for immune suppression during endotoxemia or sepsis. To verify our hypothesis that pre-enrichment of the lamina propria (LP) DC pool may improve protective immunity to bacterial translocation and outcome in endotoxemic mice, we pre-treated mice with Flt3L or normal saline, and then challenged them with or without LPS. Twelve hours later the population size and maturity of DC in the LP and circulation were analyzed by flow cytometry. Bacterial translocation to distant organs, inflammatory responses in the intestine and the survival rate of mice were evaluated. We observed that pretreatment of Flt3L significantly expanded DC in the LP and blood, but did not alter their maturation. However, exacerbation of DC growth induced by Flt3L-pretreatment aggravated intestinal inflammation and increased the mortality of endotoxemic mice rather than enhancing their resistance to bacterial translocation.