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Macrophage activation participates in the pathogenesis of pulmonary inflammation. As a coenzyme, vitamin B6 (VitB6) is mainly involved in the metabolism of amino acids, nucleic acids, glycogen and lipids. We have previously reported that activation of AMP-activated protein kinase (AMPK) produces anti-inflammatory effects both in vitro and in vivo. Whether VitB6 via AMPK activation prevents pulmonary inflammation remains unknown. The model of acute pneumonia was induced by injecting mice with lipopolysaccharide (LPS). The inflammation was determined by measuring the levels of interleukin-1 beta (IL-1ß), IL-6 and tumour necrosis factor alpha (TNF-α) using real time PCR, ELISA and immunohistochemistry. Exposure of cultured primary macrophages to VitB6 increased AMP-activated protein kinase (AMPK) Thr172 phosphorylation in a time/dose-dependent manner, which was inhibited by compound C. VitB6 downregulated the inflammatory gene expressions including IL-1ß, IL-6 and TNF-α in macrophages challenged with LPS. These effects of VitB6 were mirrored by AMPK activator 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR). However, VitB6 was unable to inhibit LPS-induced macrophage activation if AMPK was in deficient through siRNA-mediated approaches. Further, the anti-inflammatory effects produced by VitB6 or AICAR in LPS-treated macrophages were abolished in DOK3 gene knockout (DOK3-/- ) macrophages, but were enhanced in macrophages if DOK3 was overexpressed. In vivo studies indicated that administration of VitB6 remarkably inhibited LPS-induced both systemic inflammation and acute pneumonia in wild-type mice, but not in DOK3-/- mice. VitB6 prevents LPS-induced acute pulmonary inflammation in mice via the inhibition of macrophage activation.
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Proteínas Adaptadoras Transductoras de Señales/genética , Interleucina-1beta/genética , Neumonía/tratamiento farmacológico , Factor de Necrosis Tumoral alfa/genética , Vitamina B 6/farmacología , Proteínas Quinasas Activadas por AMP/genética , Animales , Modelos Animales de Enfermedad , Humanos , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/genética , Inflamación/patología , Lipopolisacáridos/toxicidad , Activación de Macrófagos/efectos de los fármacos , Ratones , Fosforilación/efectos de los fármacos , Neumonía/inducido químicamente , Neumonía/genética , Neumonía/patología , Transducción de SeñalRESUMEN
Poly (ADP-ribose) polymerase (PARP) plays an important role in endothelial dysfunction, leading to atherogenesis and vascular-related diseases. However, whether PARP regulates nitric oxide (NO), a key regulator of endothelial function, is unclear so far. We investigated whether inhibition of PARP-1, the most abundant PARP isoform, prevents atherogenesis by regulating NO production and tried to elucidate the possible mechanisms involved in this phenomenon. In apolipoprotein E-deficient (apoE-/- ) mice fed a high-cholesterol diet for 12 weeks, PARP-1 inhibition via treatment with 3,4-dihydro-54-(1-piperindinyl) butoxy-1(2H)-isoquinoline (DPQ) or PARP-1 gene knockout reduced aortic atherosclerotic plaque areas (49% and 46%, respectively). Both the groups showed restored NO production in mouse aortas with reduced arginase II (Arg II) expression compared to that in the controls. In mouse peritoneal macrophages and aortic endothelial cells (MAECs), PARP-1 knockout resulted in lowered Arg II expression. Moreover, phosphorylation of endothelial NO synthase (eNOS) was preserved in the aortas and MAECs when PARP-1 was inhibited. Reduced NO production in vitro due to PARP-1 deficiency could be restored by treating the MAECs with oxidized low-density lipoprotein treatment, but this effect could not be achieved with peritoneal macrophages, which was likely due to a reduction in the expression of induced NOS expression. Our findings indicate that PARP-1 inhibition may attenuate atherogenesis by restoring NO production in endothelial cells and thus by reducing Arg II expression and consequently arginase the activity.
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Aorta/metabolismo , Arginasa/metabolismo , Aterosclerosis/metabolismo , Regulación hacia Abajo/fisiología , Óxido Nítrico/biosíntesis , Poli(ADP-Ribosa) Polimerasa-1/deficiencia , Animales , Aterosclerosis/inducido químicamente , Aterosclerosis/prevención & control , Células Cultivadas , Colesterol en la Dieta/efectos adversos , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones TransgénicosRESUMEN
Diabetic nephropathy (DN) is one of the most important diabetic microangiopathies. The epithelial-to-mesenchymal transition (EMT) plays an important role in DN. The physiological role of microRNA-21 (miR-21) was closely linked to EMT. However, it remained elusive whether tongxinluo (TXL) ameliorated renal structure and function by regulating miR-21-induced EMT in DN. This study aimed to determine the effect of TXL on miR-21-induced renal tubular EMT and to explore the relationship between miR-21 and TGF-ß1/smads signals. Real-time RT-PCR, cell transfection, in situ hybridization (ISH), and laser confocal microscopy were used, respectively. Here, we revealed that TXL dose dependently lowered miR-21 expression in tissue, serum, and cells. Overexpression of miR-21 can enhance α-smooth muscle actin (SMA) expression and decrease E-cadherin expression by upregulating smad3/p-smad3 expression and downregulating smad7 expression. Interestingly, TXL also increased E-cadherin expression and decreased α-SMA expression by regulating miR-21 expression. More importantly, TXL decreased collagen IV, fibronectin, glomerular basement membrane, glomerular area, and the albumin/creatinine ratio, whereas it increased the creatinine clearance ratio. The results demonstrated that TXL ameliorated renal structure and function by regulating miR-21-induced EMT, which was one of the mechanisms to protect against DN, and that miR-21 may be one of the therapeutic targets for TXL in DN.
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Nefropatías Diabéticas/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Transición Epitelial-Mesenquimal/efectos de los fármacos , MicroARNs/metabolismo , Cadherinas/metabolismo , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/genética , Línea Celular , Nefropatías Diabéticas/genética , Nefropatías Diabéticas/metabolismo , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Transición Epitelial-Mesenquimal/genética , HumanosRESUMEN
BACKGROUND: Targeted therapy (TT) has resulted in controversial efficacy as first-line treatment for biliary tract cancer (BTC). More efficacy comparisons are required to clarify the overall effects of chemotherapy (CT) combined with TT and CT alone on advanced BTC. AIM: To conduct a meta-analysis of the available evidence on the efficacy of CT combined with TT for advanced BTC. METHODS: The PubMed, EMBASE, ClinicalTrials, Scopus and Cochrane Library databases were systematically searched for relevant studies published from inception to August 2022. Only randomized clinical trials (RCTs) including comparisons between the combination of gemcitabine-based CT with TT and CT alone as first-line treatment for advanced BTC were eligible (PROSPERO-CRD42022313001). The odds ratios (ORs) for the objective response rate (ORR) and hazard ratios (HRs) for both progression-free survival (PFS) and overall survival (OS) were calculated and analyzed. Subgroup analyses based on different targeted agents, CT regimens and tumor locations were prespecified. RESULTS: Nine RCTs with a total of 1361 individuals were included and analyzed. The overall analysis showed a significant improvement in ORR in patients treated with CT + TT compared to those treated with CT alone (OR = 1.43, 95%CI: 1.11-1.86, P = 0.007) but no difference in PFS or OS. Similar trends were observed in the subgroup treated with agents targeting epidermal growth factor receptor (OR = 1.67, 95%CI: 1.17-2.37, P = 0.004) but not in the subgroups treated with agents targeting vascular endothelial growth factor receptor or mesenchymal-epithelial transition factor. Notably, patients who received a CT regimen of gemcitabine + oxaliplatin in the CT + TT arm had both a higher ORR (OR = 1.75, 95%CI: 1.20-2.56, P = 0.004) and longer PFS (HR = 0.83, 95%CI: 0.70-0.99, P = 0.03) than those in the CT-only arm. Moreover, patients with cholangiocarcinoma treated with CT + TT had significantly increased ORR and PFS (ORR, OR = 2.06, 95%CI: 1.27-3.35, PFS, HR = 0.79, 95%CI: 0.66-0.94). CONCLUSION: CT + TT is a potential first-line treatment for advanced BTC that leads to improved tumor control and survival outcomes, and highlighting the importance of CT regimens and tumor types in the application of TT.
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The development of covalent organic framework nanosheet (COF NS) is becoming a vitally important research field by reason of its high permeability, ordered structure, high utilization of functional site, favourable dispersability and large aspect ratio, resulting in their widespread applications in separation, catalysis, sensing and optical device. In this work, a Tp-Bpy COF NS was prepared via an interfacial synthesis of 2,4,6-triformylphloroglucinol (Tp) and 5,5'-diamino-2,2'-bipyridine (Bpy), which has film morphology, high surface area, large pore, excellent stability and various functional site. It was utilized as a functional material to immobilize aptamers for constructing a sensitive electrochemical aptasensor. Compared with bulk Tp-Bpy COF, Tp-Bpy COF NS can significantly enhance the biosensing performance toward ultra-trace tobramycin. This work is benefit for the exploration of COF NSs and their electrochemical aptasensors in biosensing applications.
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Aptámeros de Nucleótidos , Técnicas Biosensibles , Estructuras Metalorgánicas , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Límite de Detección , Estructuras Metalorgánicas/químicaRESUMEN
Background: Post-stroke depression (PSD) constitutes an essential complication of stroke and is associated with high-risk unfavorable outcome after stroke. The main objective of this prospective study was to determine the relationship between early-onset PSD (1 month after stroke) and functional outcomes 5 years after baseline enrollment. Methods: Four hundred thirty-six patients who met the criteria were included in this study from October 2013 to February 2015. The follow-up time for each patient was ~5 years, with follow-up every 3 months. Patients received questionnaires including the 17-item Hamilton Depression Scale (HAMD), the Mini-Mental State Examination (MMSE), the National Institutes of Health Stroke Scale (NIHSS), the modified Rankin Scale (mRS), and the Barthel Index (BI). Results: Of the 436 patients, 154 (35.3%) patients with the prevalence of PSD status at baseline, 26 (7.2%) patients with the prevalence of PSD status, and 73 (20.1%) had an unfavorable outcome 5 years after stroke. The odds ratio (OR) for unfavorable outcome at 5 years in the PSD group was ~2.2 relative to the non-PSD group after adjusting for potential risk factors [OR = 2.217, 95% confidence interval (CI) = 1.179-4.421, P = 0.015]. In the early-onset PSD group, HAMD scores were independently associated with 5-year unfavorable outcome rates (OR = 1.168, 95% CI = 1.015-1.345, P = 0.031). Conclusions: Our findings indicate that early-onset PSD status in Chinese patients is an independent risk factor for unfavorable outcome 5 years after stroke, and that the severity of PSD is also related to unfavorable outcome.
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BACKGROUND AND PURPOSE: Previous studies have established that vitamin D was associated with stroke. The purpose of this study was to investigate the relationship between vitamin D and 5-year outcome of patients with stroke including acute ischemic stroke (AIS) and intracranial hemorrhage (ICH) stroke. METHODS: Serum 25-hydroxyvitamin D levels were prospectively analyzed in patients admitted to the First Affiliated Hospital of Wenzhou Medical University from 2013 to 2015. Modified Rankin scale (mRS) was used to evaluate their 5-year functional outcome, and univariate and multivariate logistic regressions were applied to evaluate the effects of vitamin D on stroke outcome. RESULTS: In total, 668 patients diagnosed with stroke were recruited, and 420 completed the 5-year follow-up. Ninety-five patients experienced poor outcome in the 5 years since stroke onset. Vitamin D levels in patients with poor outcome showed significant differences compared to good outcome patients (p < .001). In multivariable logistic regression analysis, after adjusting the potential confounders, the 5-year functional outcome was significantly associated with vitamin D levels. Stroke patients with vitamin D levels less than 38.4 nmol/L had a higher risk for poor outcome compared with those with vitamin D level over 71.4 nmol/L at 5-year (odds ratio [OR] = 3.66, 95% confidence interval [CI] = 1.42-9.45, p = .007), which was consistent with AIS patients (OR = 6.36, 95% CI = 1.89-21.44, p = .003). CONCLUSION: Vitamin D level less than 38.4 nmol/L at admission is a potential risk biomarker for poor functional outcome at 5-year prognosis in AIS patients, which might provide new ideas for the prognostic assessment of stroke.
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Isquemia Encefálica , Accidente Cerebrovascular , Isquemia Encefálica/epidemiología , Humanos , Hemorragias Intracraneales , Pronóstico , Accidente Cerebrovascular/epidemiología , Vitamina DRESUMEN
[This corrects the article DOI: 10.3389/fpsyt.2021.556981.].
RESUMEN
Macroangiopathy is a complication of Type II Diabetes Mellitus (T2DM), which is mainly caused by fibrosis of blood vessels. Using T2DM rat models, we investigated whether the traditional Chinese medicine, Di-Dang Decoction (DDD), exhibited anti-fibrotic actions on great vessels. T2DM rats were randomly divided into non-intervention group, early-, middle-, late-stage DDD intervention groups and control groups, including pioglitazone group and aminoguanidine group. After administration of DDD to T2DM rats at different times, we detected the amount of extracellular matrix (ECM) deposition in the thoracic aorta. The results showed that early-stage intervention with DDD could effectively protect great vessels from ECM deposition. Considering that TGF-ß1 is the master regulator of fibrosis, we further validated at the molecular level that, compared to middle- and late-stage intervention with DDD, early-stage intervention with DDD could significantly decrease the expression levels of factors related to the activated TGF-ß1/Smad signalling pathway, as well as the expression levels of downstream effectors including CTGF, MMP and TIMP family proteins, which were directly involved in ECM remodelling. Therefore, early-stage intervention with DDD can reduce macrovascular fibrosis and prevent diabetic macroangiopathy.
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Complicaciones de la Diabetes/prevención & control , Medicamentos Herbarios Chinos/uso terapéutico , Fibrosis/prevención & control , Transducción de Señal/efectos de los fármacos , Enfermedades Vasculares/prevención & control , Animales , China , Diabetes Mellitus Experimental , Masculino , Ratas , Ratas Sprague-Dawley , Proteínas Smad/metabolismo , Factor de Crecimiento Transformador beta1/metabolismoRESUMEN
OBJECTIVE: To explore the effect of regulating A20 expression on NF-κB and biological characteristics of Jurkat cells with glucocorticoid (GC) resistance. METHODS: CCRF CEM and Jurkat cells were treated with dexamethasone (DEX) at concentrations of 100ã10ã1ã0.1ã0.01 and 0.001 µmol/L, and cultured for 24ã48 and 72 h. The proliferation inhibition rate of Jurkat cell was detected by CCK-8. A20 plasmid was constructed, A20-siRNA was designed and synthesized, and transfected into Jurkat cells by liposome. CCK-8 was used to detect the proliferation rates of Jurkat cells in different concentrations of DEX group, DEX combined with A20 plasmid group and A20-siRNA group. The mRNA expression level of NF-κB was detected by RT-qPCR, the protein expression level of NF-κB was detected by Western blot, and the apoptosis of Jurkat cells was examined by flow cytometry. RESULTS: The inhibitory effects of DEX at different concentrations on the growth of CCRF CEM cells were time-dependent (r=0.984, Pï¼0.05) and concentration-dependent (r=0.966, Pï¼0.05). At the point of 24 hour, the IC50 approached 1 µmol/L in CCRF CEM cells. Great large differences began to appear between 1 and 10 µmol/L, the proliferation rate of Jurkat cells treated with 1 µmol/L DEX did not show a significant change. Therefore, 1 µmol/L was selected as control group. The cell proliferation rate of A20 plasmid transfection combined with different concentrations of DEX group was lower than that of DEX group and A20-siRNA combined with DEX group. After transfection of A20 plasmid, the expression level of NF-κB was significantly lower than that of control group (Pï¼0.05), and the apoptotic rate was significantly higher than that of control group (Pï¼0.05). After transfection of Jurkat cells with A20-siRNA, the expression level of NF-κB was significantly higher than that of control group (Pï¼0.05). The apoptotic rate of cells in A20-siRNA group was not significantly changed (Pï¼0.05). CONCLUSION: Jurkat cells are resistant to DEX. A20 overexpression combined with DEX can increase sensitivity of Jurkat cells with GC resistance and decrease the proliferation rate of Jurkat cells, down-regulate the expression level of NF-κB and promote the apoptosis of Jurkat cells.
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Apoptosis , FN-kappa B , Proliferación Celular , Humanos , Células Jurkat , ARN Interferente Pequeño , Transfección , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfaRESUMEN
Development of nitrate tolerance is a major drawback to nitrate therapy. Prostacyclin (PGI2) is a powerful vasodilator produced from prostaglandin (PGH2) by prostacyclin synthase (PGIS) in endothelial cells. This study aimed to determine the role of PGIS S-nitrosylation in nitrate tolerance induced by nitroglycerin (GTN). In endothelial cells, GTN increased PGIS S-nitrosylation and disturbed PGH2 metabolism, which were normalized by mutants of PGIS cysteine 231/441 to alanine (C231/441A). Clearance of nitric oxide by carboxy-PTIO or inhibition of S-nitrosylation by N-acetyl-cysteine decreased GTN-induced PGIS S-nitrosylation. Enforced expression of mutated PGIS with C231/441A markedly abolished GTN-induced PGIS S-nitrosylation and nitrate cross-tolerance in Apoe-/- mice. Inhibition of cyclooxygenase 1 by aspirin, supplementation of PGI2 by beraprost, and inhibition of PGIS S-nitrosylation by N-acetyl-cysteine improved GTN-induced nitrate cross-tolerance in rats. In patients, increased PGIS S-nitrosylation was associated with nitrate tolerance. In conclusion, GTN induces nitrate cross-tolerance through PGIS S-nitrosylation at cysteine 231/441.
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Sistema Enzimático del Citocromo P-450/metabolismo , Tolerancia a Medicamentos/fisiología , Oxidorreductasas Intramoleculares/metabolismo , Nitratos/metabolismo , Óxido Nítrico/metabolismo , Nitroglicerina/farmacología , Anciano , Anciano de 80 o más Años , Secuencia de Aminoácidos , Animales , Bovinos , Cricetinae , Sistema Enzimático del Citocromo P-450/genética , Relación Dosis-Respuesta a Droga , Femenino , Células Endoteliales de la Vena Umbilical Humana , Humanos , Oxidorreductasas Intramoleculares/genética , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Ratas , Ratas Sprague-Dawley , Vasodilatadores/farmacologíaRESUMEN
Diabetes mellitus is one of risk factors of cardiovascular diseases including atherosclerosis. Whether and how diabetes promotes the formation of unstable atherosclerotic plaque is not fully understood. Here, we show that streptozotocin-induced type 1 diabetes reduced collagen synthesis, leading to the formation of unstable atherosclerotic plaque induced by collar placement around carotid in apolipoprotein E knockout (Apoe-/-) mice. These detrimental effects of hyperglycemia on plaque stability were reversed by metformin in vivo without altering the levels of blood glucose and lipids. Mechanistically, we found that high glucose reduced the phosphorylated level of AMP-activated protein kinase alpha (AMPKα) and the transcriptional activity of activator protein 2 alpha (AP-2α), increased the expression of miR-124 expression, and downregulated prolyl-4-hydroxylase alpha 1 (P4Hα1) protein expression and collagen biosynthesis in cultured vascular smooth muscle cells. Importantly, these in vitro effects produced by high glucose were abolished by AMPKα pharmacological activation or adenovirus-mediated AMPKα overexpression. Further, adenovirus-mediated AMPKα gain of function remitted the process of diabetes-induced plaque destabilization in Apoe-/- mice injected with streptozotocin. Administration of metformin enhanced pAP-2α level, reduced miR-124 expression, and increased P4Hα1 and collagens in carotid atherosclerotic plaque in diabetic Apoe-/- mice. We conclude that streptozotocin-induced toxic diabetes promotes the formation of unstable atherosclerotic plaques based on the vulnerability index in Apoe-/- mice, which is related to the inactivation of AMPKα/AP-2α/miRNA-124/P4Hα1 axis. Clinically, targeting AMPKα/AP-2α/miRNA-124/P4Hα1 signaling should be considered to increase the plaque stability in patients with atherosclerosis. KEY MESSAGES: Hyperglycemia reduced collagen synthesis, leading to the formation of unstable atherosclerotic plaque induced by collar placement around carotid in apolipoprotein E knockout mice. Hyperglycemia destabilizes atherosclerotic plaque in vivo through an AMPKα/AP-2α/miRNA-124/P4Hα1-dependent collagen synthesis. Metformin functions as a stabilizer of atherosclerotic plaque to reduce acute coronary accent.
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Proteínas Quinasas Activadas por AMP/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , MicroARNs/metabolismo , Placa Aterosclerótica/metabolismo , Procolágeno-Prolina Dioxigenasa/metabolismo , Factor de Transcripción AP-2/metabolismo , Animales , Colágeno Tipo I/metabolismo , Colágeno Tipo II/metabolismo , Hipoglucemiantes/farmacología , Masculino , Metformina/farmacología , Ratones Noqueados para ApoE , Miocitos del Músculo Liso/metabolismoRESUMEN
The aims of our study were to evaluate the effects of Saccharomyces boulardii (S. boulardii) on deoxynivalenol (DON)-induced injury in porcine alveolar macrophage cells (PAMCs) and to explore the underlying mechanisms. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometric analysis, ELISA, qRT-PCR, and western blot were performed to assess whether S. boulardii could prevent DON-induced injury by p38 mitogen-activated protein kinase (p38 MAPK) signal pathway. The results showed that pretreatment with 8 µM DON could decrease the viability of PAMC and significantly increase the apoptosis rate of PAMC, whereas S. boulardii could rescue apoptotic PAMC cells induced by DON. Further experiments revealed that S. boulardii effectively reversed DON-induced cytotoxicity via downregulating the expression of TNF-α, IL-6, and IL-lß. In addition, S. boulardii significantly alleviated DON-induced phosphorylation and mRNA expression of p38 and further increased the expression of apoptosis regulation genes Bcl-xl and Bcl-2 and inhibited the activation of Bax. Our results suggest that S. boulardii could suppress DON-induced p38 MAPK pathway activation and reduce the expression of downstream inflammatory cytokines, as well as promote the expression of anti-apoptotic genes to inhibit apoptosis induced by DON in PAMC.
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Macrófagos Alveolares/efectos de los fármacos , Factores Protectores , Saccharomyces boulardii/metabolismo , Transducción de Señal , Tricotecenos/toxicidad , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Técnicas de Cocultivo , Regulación de la Expresión Génica , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Macrófagos Alveolares/citología , Macrófagos Alveolares/metabolismo , Fosforilación , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Saccharomyces boulardii/crecimiento & desarrollo , Porcinos , Tricotecenos/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
We have previously reported that activation of AMP-activated kinase alpha 2 (AMPKα2) by nicotine or angiotensin II (AngII) instigates formation of abdominal aortic aneurysms (AAA) in Apoe-/- mice. Statins, used to treat hyperlipidemia widely, activate AMPK in vascular cells. We sought to examine the effects of pravastatin on AAA formation and uncover the molecular mechanism. The AAA model was induced by AngII and evaluated by incidence, elastin degradation, and maximal abdominal aortic diameter in Apoe-/- mice. The phosphorylated levels of AMPKα2 and activator protein 2 alpha (AP-2α) were examined in cultured vascular smooth muscle cells (VSMCs) or in mice. We observed that pravastatin (50 mg/kg/day, 8 weeks) remarkably increased the AngII-induced AAA incidence in mice. In VSMCs, pravastatin increased the levels of pAMPK, pAP-2α, and MMP2 in both basal and AngII-stressed conditions, which were abolished by tempol and compound C. Pravastatin-upregulated MMP2 was abrogated by AMPKα2 or AP-2α siRNA. Lentivirus-mediated gene silence of AMPKα2 or AP-2α abolished pravastatin-worsened AAA formations in AngII-infused Apoe-/- mice. Clinical investigations demonstrated that both AMPKα2 and AP-2α phosphorylations were increased in AAA patients or human subjects taking pravastatin. In conclusion, pravastatin promotes AAA formation through AMPKα2-dependent AP-2α activations.
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Proteínas Quinasas Activadas por AMP/metabolismo , Angiotensina II/efectos adversos , Aneurisma de la Aorta Abdominal/etiología , Apolipoproteínas E/fisiología , Regulación de la Expresión Génica/efectos de los fármacos , Pravastatina/efectos adversos , Factor de Transcripción AP-2/metabolismo , Animales , Anticolesterolemiantes/farmacología , Aneurisma de la Aorta Abdominal/metabolismo , Aneurisma de la Aorta Abdominal/patología , Western Blotting , Células Cultivadas , Modelos Animales de Enfermedad , Humanos , Masculino , Ratones , Ratones Noqueados , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , Fosforilación , Transducción de SeñalRESUMEN
Epithelial-to-mesenchymal transition (EMT) plays an important role in renal interstitial fibrosis (RIF) with diabetic nephropathy (DN). Smad7 (a inhibitory smad), a downstream signaling molecules of TGF-ß1, represses the EMT. The physiological function of miR-21 is closely linked to EMT and RIF. However, it remained unclear whether miR-21 over-expression affected TGF-ß1-induced EMT by regulating smad7 in DN. In this study, real-time RT-PCR, cell transfection, luciferase reporter gene assays, western blot and confocal microscope were used, respectively. Here, we found that miR-21 expression was upregulated by TGF-ß1 in time- and concentration -dependent manner. Moreover, miR-21 over-expression enhanced TGF-ß1-induced EMT(upregulation of a-SMA and downregulation of E-cadherin) by directly down-regulating smad7/p-smad7 and indirectly up-regulating smad3/p-smad3, accompanied by the decrease of Ccr and the increase of col-IV, FN, the content of collagen fibers, RTBM, RTIAW and ACR. Meantime, the siRNA experiment showed that smad7 can directly regulate a-SMA and E-cadherin expression. More importantly, miR-21 inhibitor can not only inhibit EMT and fibrosis but also ameliorate renal structure and function. In conclusion, our results demonstrated that miR-21 overexpression can contribute to TGF-ß1-induced EMT by inhibiting target smad7, and that targeting miR-21 may be a better alternative to directly suppress TGF-ß1-mediated fibrosis in DN.