RESUMO
Autophagy is a cellular mechanism that protects cells from stress by digesting non-functional cellular components. In the cartilage, chondrocytes depend on autophagy as a principal mechanism to maintain cellular homeostasis. This protective role diminishes prior to the structural damage that normally occurs during aging. Considering that aging is the main risk factor for osteoarthritis, evaluating the expression of genes associated with autophagy in senescent cartilage might allow for the identification of potential therapeutic targets for treatment. Thus, we studied two groups of young and senescent rats. A histological analysis of cartilage and gene expression quantification for autophagy-related genes were performed. In aged cartilage, morphological changes were observed, such as an increase in cartilage degeneration as measured by the modified Mankin score, a decrease in the number of chondrocytes and collagen II (Col2a1), and an increase in matrix metalloproteinase 13 (Mmp13). Moreover, 84 genes associated with autophagy were evaluated by a PCR array analysis, and 15 of them were found to be significantly decreased with aging. Furthermore, an in silico analysis based on by two different bioinformatics software tools revealed that several processes including cellular homeostasis, autophagosome assembly, and aging-as well as several biological pathways such as autophagy, insulin-like growth factor 1 (IGF-1) signaling, PI3K (phosphoinositide 3-kinase)/AKT (serine/threonine kinase) signaling, and mammalian target of rapamycin (mTOR) signaling-were enriched. In conclusion, the analysis identified some potential targets for osteoarthritis treatment that would allow for the development of new therapeutic strategies for this chronic disease.
Assuntos
Envelhecimento , Autofagia , Cartilagem/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Transdução de Sinais , Envelhecimento/genética , Envelhecimento/metabolismo , Animais , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
Atherosclerosis is a chronic inflammatory disease, whose progression and stability are modulated, among other factors, by an innate and adaptive immune response. Prodiginines are bacterial secondary metabolites with antiproliferative and immunomodulatory activities; however, their effect on the progression or vulnerability of atheromatous plaque has not been evaluated. This study assessed the therapeutic potential of prodigiosin and undecylprodigiosin on inflammatory marker expression and atherosclerosis. An in vitro and in vivo study was carried out. Migration, low-density lipoprotein (LDL) uptake and angiogenesis assays were performed on cell types involved in the pathophysiology of atherosclerosis. In addition, male LDL receptor null (Ldlr-/-) C57BL/6J mice were treated with prodigiosin or undecylprodigiosin for 28 days. Morphometric analysis of atherosclerotic plaques, gene expression of atherogenic factors in the aortic sinus and serum cytokine quantification were performed. The treatments applied had slight effects on the in vitro tests performed, highlighting the inhibitory effect on the migration of SMCs (smooth muscle cells). On the other hand, although no significant difference in atherosclerotic plaque progression was observed, gene expression of IL-4 and chemokine (C-C motif) ligand 2 (Ccl2) was downregulated. In addition, 50 µg/Kg/day of both treatments was sufficient to inhibit circulating tumor necrosis factor alpha (TNF-α), interleukin-2 (IL-2) and interferon-gamma (IFN-γ) in serum. These results suggested that prodigiosin and undecylprodigiosin modulated inflammatory markers and could have an impact in reducing atherosclerotic plaque vulnerability.
Assuntos
Aterosclerose/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Imunidade/efeitos dos fármacos , Prodigiosina/análogos & derivados , Receptores de LDL/fisiologia , Animais , Aterosclerose/tratamento farmacológico , Aterosclerose/patologia , Citocinas/metabolismo , Imunossupressores/farmacologia , Lipídeos/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Prodigiosina/farmacologiaRESUMO
BACKGROUND: Osteoarthritis (OA) is a progressive and multifactorial disease that is associated with aging. A number of changes occur in aged cartilage, such as increased oxidative stress, decreased markers of healthy cartilage, and alterations in the autophagy pathway. Propolis extracts contain a mixture of polyphenols and it has been proved that they have high antioxidant capacity and could regulate the autophagic pathway. Our objective was to evaluate the effect of ethanolic extract of propolis (EEP) on chondrocytes that were stimulated with IL-1ß. METHODS: Rabbit chondrocytes were isolated and stimulated with IL-1ß and treated with EEP. We evaluated cell viability, nitric oxide production, healthy cartilage, and OA markers, and the expression of three proteins associated with the autophagy pathway LC3, ATG5, and AKT1. RESULTS: The EEP treatment reduces the expression of LC3, ATG5, and AKT1, reduces the production of nitric oxide, increases the expression of healthy markers, and reduces OA markers. CONCLUSIONS: These results suggest that treatment with EEP in chondrocytes that were stimulated with IL-1ß has beneficial effects, such as a decrease in the expression of proteins associated with autophagy, MMP13, and production of nitric oxide, and also increased collagen II.
Assuntos
Antioxidantes/farmacologia , Proteínas Relacionadas à Autofagia/metabolismo , Condrócitos/efeitos dos fármacos , Interleucina-1beta/metabolismo , Própole/farmacologia , Animais , Autofagia/efeitos dos fármacos , Células Cultivadas , Condrócitos/metabolismo , Metaloproteinase 13 da Matriz/metabolismo , Óxido Nítrico/metabolismo , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , CoelhosRESUMO
BACKGROUND: Obesity and insulin resistance/diabetes are important risk factors for cardiovascular diseases and demand safe and efficacious therapeutics. OBJECTIVE: To assess the effects of a new thiazolidine compound-GQ-11-on obesity and insulin resistance induced by a diabetogenic diet in LDL receptor-deficient (LDLr-/-) mice. METHODS: Molecular docking simulations of GQ-11, PPARα and PPARγ structures were performed. Male C57BL/6J LDLr-/- mice fed a diabetogenic diet for 24 weeks were treated with vehicle, GQ-11 or pioglitazone or (20 mg/kg/day) for 28 days by oral gavage. Glucose tolerance test, insulin, HOMA-IR, adipokines (leptin, adiponectin) and the lipid profile were assessed after treatment. Adipose tissue was analysed by X-ray analysis and morphometry; gene and protein expression were evaluated by real-time PCR and western blot, respectively. RESULTS: GQ-11 showed partial agonism to PPARγ and PPARα. In vivo, treatment with GQ-11 ameliorated insulin sensitivity and did not modify subcutaneous adipose tissue and body weight gain. In addition, GQ-11 restored adipokine imbalance induced by a diabetogenic diet and enhanced Glut-4 expression in the adipose tissue. Improved insulin sensitivity was also associated with lower levels of MCP-1 and higher levels of IL-10. Furthermore, GQ-11 reduced triglycerides and VLDL cholesterol and increased HDL-cholesterol by upregulation of Apoa1 and Abca1 gene expression in the liver. CONCLUSION: GQ-11 is a partial/dual PPARα/γ agonist that demonstrates anti-diabetic effects. Additionally, it improves the lipid profile and ameliorates chronic inflammation associated with obesity in atherosclerosis-prone mice.
Assuntos
Indóis/farmacologia , Obesidade/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/agonistas , Receptores de LDL/metabolismo , Tiazolidinas/farmacologia , Adipocinas/sangue , Animais , Peso Corporal/efeitos dos fármacos , Indóis/química , Inflamação/metabolismo , Lipídeos/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Obesos , Receptores de LDL/genética , Tiazolidinas/químicaRESUMO
Peroxisome proliferator-activated receptor gamma (PPARγ) regulates multiple pathways involved in the pathogenesis of obesity and atherosclerosis. Here, we evaluated the therapeutic potential of GQ-177, a new thiazolidinedione, on diet-induced obesity and atherosclerosis. The intermolecular interaction between PPARγ and GQ-177 was examined by virtual docking and PPAR activation was determined by reporter gene assay identifying GQ-177 as a partial and selective PPARγ agonist. For the evaluation of biological activity of GQ-177, low-density lipoprotein receptor-deficient (LDLr(-/-)) C57/BL6 mice were fed either a high fat diabetogenic diet (diet-induced obesity), or a high fat atherogenic diet, and treated with vehicle, GQ-177 (20mg/kg/day), pioglitazone (20mg/kg/day, diet-induced obesity model) or rosiglitazone (15mg/kg/day, atherosclerosis model) for 28 days. In diet-induced obesity mice, GQ-177 improved insulin sensitivity and lipid profile, increased plasma adiponectin and GLUT4 mRNA in adipose tissue, without affecting body weight, food consumption, fat accumulation and bone density. Moreover, GQ-177 enhanced hepatic mRNA levels of proteins involved in lipid metabolism. In the atherosclerosis mice, GQ-177 inhibited atherosclerotic lesion progression, increased plasma HDL and mRNA levels of PPARγ and ATP-binding cassette A1 in atherosclerotic lesions. GQ-177 acts as a partial PPARγ agonist that improves obesity-associated insulin resistance and dyslipidemia with atheroprotective effects in LDLr(-/-) mice.
Assuntos
Aterosclerose/metabolismo , Obesidade/metabolismo , PPAR gama/agonistas , PPAR gama/metabolismo , Receptores de LDL/genética , Sulfonas/farmacologia , Tiazolidinedionas/farmacologia , Adiponectina/genética , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Aorta Torácica/patologia , Aterosclerose/sangue , Aterosclerose/tratamento farmacológico , Aterosclerose/patologia , Densidade Óssea , Linhagem Celular , HDL-Colesterol/sangue , Fatores de Crescimento de Fibroblastos/genética , Transportador de Glucose Tipo 4/genética , Humanos , Leptina/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos Knockout , Modelos Moleculares , Miocárdio/metabolismo , Obesidade/sangue , Obesidade/tratamento farmacológico , Obesidade/patologia , Sulfonas/uso terapêutico , Tiazolidinedionas/uso terapêuticoRESUMO
We aimed to evaluate the effects of a 24-h ultramarathon, an aerobic test of high physical load, on lipid profile and apolipoproteins B (ApoB) and A1 (ApoA1) levels, minimally modified low-density lipoprotein (LDL), and oxidised LDL. Prospective evaluation of 16 male athletes who participated in an ultramarathon run, where the objective was to run the greatest distance possible in 24 h. Fourteen participants completed the run. The mean distance achieved was 133.1 km (maximum of 169.6 km). There was a trend in reduction of triglycerides and total cholesterol (P = 0.06 and 0.05, respectively), without significant modifications in high-density lipoprotein, LDL and ApoA1 levels (P = 0.16; 0.55 and 0.67). There was a marked reduction in ApoB levels (P < 0.001), correlated directly to the distance covered (Pearson R = 0.68). Accordingly, an increase in the LDL/ApoB ratio was observed. The stress of this physical activity was not associated to an increase in minimally modified LDL or oxidised LDL. Lipid profile levels were not acutely altered by prolonged physical activity. Similarly, there was no evidence of greater oxidation of LDL over a 24-h period of physical activity. The reduction in ApoB was directly proportional to the distance covered, suggesting an acute positive change in phenotype of LDL molecules.
Assuntos
Lipídeos/sangue , Resistência Física/fisiologia , Corrida/fisiologia , Adulto , Apolipoproteína A-I/sangue , Apolipoproteínas B/sangue , Colesterol/sangue , LDL-Colesterol/sangue , Humanos , Lipoproteínas HDL/sangue , Masculino , Pessoa de Meia-Idade , Oxirredução , Triglicerídeos/sangueRESUMO
The purpose of our work was to select phages displaying peptides capable of binding to vascular markers present in human atheroma, and validate their capacity to target the vascular markers in vitro and in low-density lipoprotein receptor knockout (LDLr(-/-)) mouse model of atherosclerosis. By peptide fingerprinting on human atherosclerotic tissues, we selected and isolated four different peptides sequences, which bind to atherosclerotic lesions and share significant similarity to known human proteins with prominent roles in atherosclerosis. The CTHRSSVVC-phage peptide displayed the strongest reactivity with human carotid atherosclerotic lesions (p < 0.05), when compared to tissues from normal carotid arteries. This peptide sequence shares similarity to a sequence present in the fifth scavenger receptor cysteine-rich (SRCR) domain of CD163, which appeared to bind to CD163, and subsequently, was internalized by macrophages. Moreover, the CTHRSSVVC-phage targets atherosclerotic lesions of a low-density lipoprotein receptor knockout (LDLr(-/-)) mouse model of atherosclerosis in vivo to High-Fat diet group versus Control group. Tetraazacyclododecane-1,4,7,10-tetraacetic acid-CTHRSSVVC peptide (DOTA-CTHRSSVVC) was synthesized and labeled with (111)InCl3 in >95% yield as determined by high performance liquid chromatography (HPLC), to validate the binding of the peptide in atherosclerotic plaque specimens. The results supported our hypothesis that CTHRSSVVC peptide has a remarkable sequence for the development of theranostics approaches in the treatment of atherosclerosis and other diseases.
Assuntos
Aterosclerose/diagnóstico , Imagem Molecular/métodos , Peptídeos/metabolismo , Animais , Antígenos CD/química , Antígenos de Diferenciação Mielomonocítica/química , Aterosclerose/metabolismo , Modelos Animais de Doenças , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peptídeos/química , Receptores de Superfície Celular/química , Receptores de LDL/deficiência , Receptores de LDL/genéticaRESUMO
In this work, the purification of a single-chain variable fragment (scFv) of an antibody by using liquid-liquid extraction in aqueous micellar two-phase systems was optimized by means of central composite design. Protein partitioning assays were performed by using the selected system composition in previous works: Triton X-114 at 4% wt/wt, yeast fermentation supernatant at 60% wt/wt, McIlvaine buffer pH 7.00. The other system component concentrations, Cibacron Blue F3GA (CB), Fabsorbent™ F1P HF (HF) and NaCl, were selected as independent variables. ScFv recovery percentage (%R) and purification factor (PF) were selected as the responses. According to the optimization process both, scFv recovery percentage and purification factor were favored with the addition of HF and NaCl in a range of concentrations around the central point of the second central composite design (HF 0.0120% w/w, CB 0.0200% w/w, NaCl 0.200% w/w). These experimental conditions allowed the concentration and pre-purification of scFv in the micelle-rich bottom phase of the systems with a recovery percentage superior to 88% and a purification factor of approximately 3.5. These results improved the previously presented works and demonstrated the convenience of using aqueous micellar two-phase systems as a first step in the purification of scFv molecules.
Assuntos
Anticorpos de Cadeia Única/química , Anticorpos de Cadeia Única/isolamento & purificação , Humanos , Concentração de Íons de Hidrogênio , MicelasRESUMO
New vessel formation plays a critical role in the progression and vulnerability of atherosclerotic lesions. It has been shown that polyphenols from propolis attenuate the progression of atherosclerosis and also exert inhibitory effects on angiogenic factors. However, the mechanisms underlying these effects are not completely understood. Thus, this study aimed to identify microRNAs (miRNAs) involved in the modulation of pro-angiogenic factors in the atherosclerotic plaques of LDL receptor gene knockout mice treated with a polyphenol-rich extract of Chilean propolis. The progression of the atherosclerotic lesions was significantly attenuated in treated mice compared with control mice. Using microarray analysis and a bioinformatic approach, we identified 29 differentially expressed miRNAs. Many of these miRNAs were involved in biological processes associated with angiogenesis, such as the cell cycle, cell migration, cell growth and proliferation. Among them, three miRNAs (miR-181a, miR-106a and miR-20b) were over-expressed and inversely related to the expression of Vegfa (vascular endothelial growth factor A) and Hif1a (hypoxia inducible factor 1 alpha). In addition, VEGF-A protein expression was attenuated in histological sections obtained from the aortic sinuses of treated mice. VEGFA is a key pro-angiogenic factor in atherosclerotic plaques, and Hif1a, which is expressed in the necrotic nucleus of the atheroma, is its main inducer. We found a correlation between the over-expression of miR-181a, miR-106a and miR-20b and their target genes, Hif1a and Vegfa, which is consistent with attenuation of the atherosclerotic lesion. In conclusion, our data analysis provides evidence that the anti-angiogenic effects of polyphenols from Chilean propolis can be modulated by miRNAs, in particular miR-181a, miR-106a and miR-20b.
Assuntos
Indutores da Angiogênese/farmacologia , Aterosclerose/fisiopatologia , MicroRNAs/análise , Polifenóis/farmacologia , Própole/química , Indutores da Angiogênese/química , Animais , Masculino , Camundongos , Polifenóis/químicaRESUMO
PURPOSE: In general, the surface functionalization of polymeric nanoparticles is carried out by covalently bounding ligands to the nanoparticle surface. This process can cause a lack or decrease of the ligand specificity to its target receptor, besides the need of purification steps. We proposed a ligand-metal-chitosan-lecithin complex as a new strategy to functionalize the surface of biodegradable nanoparticles. METHODS: One pot synthesis of scFv anti-LDL(-)-functionalized nanocapsules was carried out by self-assembly and interfacial reactions. Particle sizing techniques, lipid peroxidation and molecular recognition by enzyme linked immuno sorbent assays were carried out. RESULTS: The selected formulation had unimodal size distribution with mean diameter of about 130 nm. The metals in the complex did not enhance the oxidative stress, and the scFv anti-LDL(-)-functionalized nanocapsules recognized LDL(-) and did not react with native LDL indicating the maintenance of the active site of the fragment. CONCLUSIONS: The one pot synthesis, using the ligand-metal-chitosan-lecithin complex to functionalize the surface of the biodegradable nanocapsules, maintained the active site of the antibody fragment making the device interesting for applications in nanomedicine.
Assuntos
Lipoproteínas LDL/imunologia , Nanocápsulas/química , Nanopartículas/química , Polímeros/química , Anticorpos de Cadeia Única/química , Anticorpos de Cadeia Única/imunologia , Domínio Catalítico , Química Farmacêutica/métodos , Quitosana/química , Lecitinas/química , Ligantes , Peroxidação de Lipídeos/efeitos dos fármacos , Metais/química , Estresse Oxidativo/efeitos dos fármacos , Tamanho da PartículaRESUMO
The recent discovery that peroxisome proliferator-activated receptor γ (PPARγ) targeted anti-diabetic drugs function by inhibiting Cdk5-mediated phosphorylation of the receptor has provided a new viewpoint to evaluate and perhaps develop improved insulin-sensitizing agents. Herein we report the development of a novel thiazolidinedione that retains similar anti-diabetic efficacy as rosiglitazone in mice yet does not elicit weight gain or edema, common side effects associated with full PPARγ activation. Further characterization of this compound shows GQ-16 to be an effective inhibitor of Cdk5-mediated phosphorylation of PPARγ. The structure of GQ-16 bound to PPARγ demonstrates that the compound utilizes a binding mode distinct from other reported PPARγ ligands, although it does share some structural features with other partial agonists, such as MRL-24 and PA-082, that have similarly been reported to dissociate insulin sensitization from weight gain. Hydrogen/deuterium exchange studies reveal that GQ-16 strongly stabilizes the ß-sheet region of the receptor, presumably explaining the compound's efficacy in inhibiting Cdk5-mediated phosphorylation of Ser-273. Molecular dynamics simulations suggest that the partial agonist activity of GQ-16 results from the compound's weak ability to stabilize helix 12 in its active conformation. Our results suggest that the emerging model, whereby "ideal" PPARγ-based therapeutics stabilize the ß-sheet/Ser-273 region and inhibit Cdk5-mediated phosphorylation while minimally invoking adipogenesis and classical agonism, is indeed a valid framework to develop improved PPARγ modulators that retain antidiabetic actions while minimizing untoward effects.
Assuntos
Hipoglicemiantes/farmacologia , PPAR gama/agonistas , Tiazolidinedionas/farmacologia , Aumento de Peso , Células 3T3-L1 , Animais , Quinase 5 Dependente de Ciclina/genética , Quinase 5 Dependente de Ciclina/metabolismo , Avaliação Pré-Clínica de Medicamentos , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacocinética , Ligantes , Camundongos , Células NIH 3T3 , PPAR gama/genética , PPAR gama/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilação/genética , Estrutura Secundária de Proteína , Tiazolidinedionas/química , Tiazolidinedionas/farmacocinética , Células U937RESUMO
Polyphenol-enriched fractions from natural sources have been proposed to interfere with angiogenesis in pathological conditions. We recently reported that red propolis polyphenols (RPP) exert antiangiogenic activity. However, molecular mechanisms of this activity remain unclear. Here, we aimed at characterizing molecular mechanisms to explain the impact of RPP on endothelial cells' (EC) physiology. We used in vitro and ex and in vivo models to test the hypothesis that RPP inhibit angiogenesis by affecting hypoxia-inducible factor-1α (HIF1α) stabilization in EC. RPP (10 mg/L) affected angiogenesis by reducing migration and sprouting of EC, attenuated the formation of new blood vessels, and decreased the differentiation of embryonic stem cells into CD31-positive cells. Moreover, RPP (10 mg/L) inhibited hypoxia- or dimethyloxallylglycine-induced mRNA and protein expression of the crucial angiogenesis promoter vascular endothelial growth factor (VEGF) in a time-dependent manner. Under hypoxic conditions, RPP at 10 mg/L, supplied for 1-4 h, decreased HIF1α protein accumulation, which in turn attenuated VEGF gene expression. In addition, RPP reduced the HIF1α protein half-life from ~58 min to 38 min under hypoxic conditions. The reduced HIF1α protein half-life was associated with an increase in the von Hippel-Lindau (pVHL)-dependent proteasomal degradation of HIF1α. RPP (10 mg/L, 4 h) downregulated Cdc42 protein expression. This caused a corresponding increase in pVHL protein levels and a subsequent degradation of HIF1α. In summary, we have elucidated the underlying mechanism for the antiangiogenic action of RPP, which attenuates HIF1α protein accumulation and signaling.
Assuntos
Inibidores da Angiogênese/farmacologia , Células Endoteliais/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Polifenóis/farmacologia , Própole , Inibidores da Angiogênese/química , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Embrião de Galinha , Células Endoteliais/citologia , Células Endoteliais/fisiologia , Expressão Gênica/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , Polifenóis/química , Própole/química , Estabilidade Proteica/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismoRESUMO
OBJECTIVE: Nitro-fatty acids (NO(2)-FAs) are emerging as a new class of cell signaling mediators. Because NO(2)-FAs are found in the vascular compartment and their impact on vascularization remains unknown, we aimed to investigate the role of NO(2)-FAs in angiogenesis. METHODS AND RESULTS: The effects of nitrolinoleic acid and nitrooleic acid were evaluated on migration of endothelial cell (EC) in vitro, EC sprouting ex vivo, and angiogenesis in the chorioallantoic membrane assay in vivo. At 10 µmol/L, both NO(2)-FAs induced EC migration and the formation of sprouts and promoted angiogenesis in vivo in an NO-dependent manner. In addition, NO(2)-FAs increased intracellular NO concentration, upregulated protein expression of the hypoxia inducible factor-1α (HIF-1α) transcription factor by an NO-mediated mechanism, and induced expression of HIF-1α target genes, such as vascular endothelial growth factor, glucose transporter-1, and adrenomedullin. Compared with typical NO donors such as spermine-NONOate and deta-NONOate, NO(2)-FAs were slightly less potent inducers of EC migration and HIF-1α expression. Short hairpin RNA-mediated knockdown of HIF-1α attenuated the induction of vascular endothelial growth factor mRNA expression and EC migration stimulated by NO(2)-FAs. CONCLUSION: Our data disclose a novel physiological role for NO(2)-FAs, indicating that these compounds induce angiogenesis in an NO-dependent mechanism via activation of HIF-1α.
Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Ácidos Linoleicos/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Nitrocompostos/farmacologia , Ácidos Oleicos/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/fisiologia , Transportador de Glucose Tipo 1/genética , Humanos , Masculino , Óxido Nítrico/fisiologia , Ratos , Ratos Wistar , Fator A de Crescimento do Endotélio Vascular/genéticaRESUMO
OBJECTIVE: Clinical trials of statins during myocardial infarction (MI) have differed in their therapeutic regimes and generated conflicting results. This study evaluated the role of the timing and potency of statin therapy on its potential mechanisms of benefit during MI. METHODS AND RESULTS: ST-elevation MI patients (n=125) were allocated into 5 groups: no statin; 20, 40, or 80 mg/day simvastatin starting at admission; or 80 mg/day simvastatin 48 hours after admission. After 7 days, all patients switched their treatment to 20 mg/day simvastatin for an additional 3 weeks and then underwent flow-mediated dilation in the brachial artery. As of the second day, C-reactive protein (CRP) differed between non-statin users (12.0±4.1 mg/L) and patients treated with 20 (8.5±4.0 mg/L), 40 (3.8±2.5 mg/L), and 80 mg/day (1.4±1.5 mg/L), and the daily differences remained significant until the seventh day (P<0.0001). The higher the statin dose, the lower the elevation of interleukin-2 and tumor necrosis factor-α, the greater the reduction of 8-isoprostane and low-density lipoprotein(-), and the greater the increase in nitrate/nitrite levels during the first 5 days (P<0.001). Later initiation of statin was less effective than its early introduction in relation to attenuation of CRP, interleukin-2, tumor necrosis factor-α, 8-isoprostane, and low-density lipoprotein(-), as well as in increase in nitrate/nitrite levels (P<0.0001). At the 30th day, there was no longer a difference in lipid profile or CRP between groups; the flow-mediated dilation, however, was proportional to the initial statin dose and was higher for those who started the treatment early (P=0.001). CONCLUSIONS: This study demonstrates that the timing and potency of statin treatment during MI are key elements for their main mechanisms of benefit. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00906451.
Assuntos
Endotélio Vascular/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Mediadores da Inflamação/metabolismo , Infarto do Miocárdio/tratamento farmacológico , Sinvastatina/administração & dosagem , Adulto , Idoso , Análise de Variância , Biomarcadores/sangue , Brasil , Relação Dose-Resposta a Droga , Esquema de Medicação , Endotélio Vascular/imunologia , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/imunologia , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento , Vasodilatação/efeitos dos fármacosRESUMO
BACKGROUND: Advanced glycation end products (AGE) alter lipid metabolism and reduce the macrophage expression of ABCA-1 and ABCG-1 which impairs the reverse cholesterol transport, a system that drives cholesterol from arterial wall macrophages to the liver, allowing its excretion into the bile and feces. Oxysterols favors lipid homeostasis in macrophages and drive the reverse cholesterol transport, although the accumulation of 7-ketocholesterol, 7alpha- hydroxycholesterol and 7beta- hydroxycholesterol is related to atherogenesis and cell death. We evaluated the effect of glycolaldehyde treatment (GAD; oxoaldehyde that induces a fast formation of intracellular AGE) in macrophages overloaded with oxidized LDL and incubated with HDL alone or HDL plus LXR agonist (T0901317) in: 1) the intracellular content of oxysterols and total sterols and 2) the contents of ABCA-1 and ABCG-1. METHODS: Total cholesterol and oxysterol subspecies were determined by gas chromatography/mass spectrometry and HDL receptors content by immunoblot. RESULTS: In control macrophages (C), incubation with HDL or HDL + T0901317 reduced the intracellular content of total sterols (total cholesterol + oxysterols), cholesterol and 7-ketocholesterol, which was not observed in GAD macrophages. In all experimental conditions no changes were found in the intracellular content of other oxysterol subspecies comparing C and GAD macrophages. GAD macrophages presented a 45% reduction in ABCA-1 protein level as compared to C cells, even after the addition of HDL or HDL + T0901317. The content of ABCG-1 was 36.6% reduced in GAD macrophages in the presence of HDL as compared to C macrophages. CONCLUSION: In macrophages overloaded with oxidized LDL, glycolaldehyde treatment reduces the HDL-mediated cholesterol and 7-ketocholesterol efflux which is ascribed to the reduction in ABCA-1 and ABCG-1 protein level. This may contribute to atherosclerosis in diabetes mellitus.
Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Regulação para Baixo , Produtos Finais de Glicação Avançada/metabolismo , Cetocolesteróis/metabolismo , Lipoproteínas/metabolismo , Macrófagos/metabolismo , Esteróis/metabolismo , Transportador 1 de Cassete de Ligação de ATP , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Acetaldeído/análogos & derivados , Acetaldeído/farmacologia , Animais , Anticolesterolemiantes/farmacologia , Linhagem Celular , Angiopatias Diabéticas/imunologia , Angiopatias Diabéticas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/metabolismo , Receptores X do Fígado , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Receptores Nucleares Órfãos/agonistas , Oxidantes/farmacologia , Estresse OxidativoRESUMO
BACKGROUND: Previous work showed that daily ingestion of an aqueous soy extract fermented with Enterococcus faecium CRL 183 and Lactobacillus helveticus 416, supplemented or not with isoflavones, reduced the total cholesterol and non-HDL-cholesterol levels, increased the high-density lipoprotein (HDL) concentration and inhibited the raising of autoantibody against oxidized low-density lipoprotein (ox-LDL Ab) and the development of atherosclerotic lesions. OBJECTIVE: The aim of this study was to characterize the fecal microbiota in order to investigate the possible correlation between fecal microbiota, serum lipid parameters and atherosclerotic lesion development in rabbits with induced hypercholesterolemia, that ingested the aqueous soy extract fermented with Enterococcus faecium CRL 183 and Lactobacillus helveticus 416. METHODS: The rabbits were randomly allocated to five experimental groups (n = 6): control (C), hypercholesterolemic (H), hypercholesterolemic plus unfermented soy product (HUF), hypercholesterolemic plus fermented soy product (HF) and hypercholesterolemic plus isoflavone-supplemented fermented soy product (HIF). Lipid parameters and microbiota composition were analyzed on days 0 and 60 of the treatment and the atherosclerotic lesions were quantified at the end of the experiment. The fecal microbiota was characterized by enumerating the Lactobacillus spp., Bifidobacterium spp., Enterococcus spp., Enterobacteria and Clostridium spp. populations. RESULTS: After 60 days of the experiment, intake of the probiotic soy product was correlated with significant increases (P < 0.05) on Lactobacillus spp., Bifidobacterium spp. and Enterococcus spp. and a decrease in the Enterobacteria population. A strong correlation was observed between microbiota composition and lipid profile. Populations of Enterococcus spp., Lactobacillus spp. and Bifidobacterium spp. were negatively correlated with total cholesterol, non-HDL-cholesterol, autoantibodies against oxidized LDL (oxLDL Ab) and lesion size. HDL-C levels were positively correlated with Lactobacillus spp., Bifidobacterium spp., and Enterococcus spp. populations. CONCLUSION: In conclusion, daily ingestion of the probiotic soy product, supplemented or not with isoflavones, may contribute to a beneficial balance of the fecal microbiota and this modulation is associated with an improved cholesterol profile and inhibition of atherosclerotic lesion development.
Assuntos
Aterosclerose/prevenção & controle , Fezes/microbiologia , Glycine max , Metagenoma/efeitos dos fármacos , Extratos Vegetais/farmacologia , Probióticos/farmacologia , Animais , Aorta/efeitos dos fármacos , Aorta/patologia , Aterosclerose/sangue , Aterosclerose/etiologia , Carga Bacteriana/efeitos dos fármacos , Colesterol/efeitos adversos , Avaliação Pré-Clínica de Medicamentos , Enterococcus faecium , Fermentação , Hipercolesterolemia/sangue , Hipercolesterolemia/induzido quimicamente , Hipercolesterolemia/complicações , Lipídeos/sangue , Masculino , CoelhosRESUMO
Lyso-7 is a novel synthetic thiazolidinedione, which is a receptor (pan) agonist of PPAR α,ß/δ,γ with anti-inflammatory activity. We investigated the cardiotoxicity of free Lyso-7 in vitro (4.5-450 nM), and Lyso-7 loaded in polylactic acid nanocapsules (NC) in vivo (Lyso-7-NC, 1.6 mg/kg). In previous work, we characterized Lyso-7-NC. We administered intravenously Lyso-7, Lyso-7-NC, control, and blank-NC once a day for seven days in mice. We assessed cell contraction and intracellular Ca2+ transients on single mice cardiomyocytes enzymatically isolated. Lyso-7 reduced cell contraction and accelerated relaxation while lowering diastolic Ca2+ and reducing Ca2+ transient amplitude. Lyso-7 also promoted abnormal ectopic diastolic Ca2+ events, which isoproterenol dramatically enhanced. Incorporation of Lyso-7 in NC attenuated drug effects on cell contraction and prevented its impact on relaxation, diastolic Ca2+, Ca2+ transient amplitude, Ca2+ transient decay kinetics, and promotion of diastolic Ca2+ events. Acute effects of Lyso-7 on cardiomyocytes in vitro at high concentrations (450 nM) were globally similar to those observed after repeated administration in vivo. In conclusion, we show evidence for off-target effects of Lyso-7, seen during acute exposure of cardiomyocytes to high concentrations and after repeated treatment in mice. Nano-encapsulation of Lyso-7 in polymeric NC attenuated the unwanted effects, particularly ectopic Ca2+ events known to support life-threatening arrhythmias favored by stress or exercise.
RESUMO
BACKGROUND: Coadministration of any statin with ezetimibe is as effective as using high doses of the same statin in the reduction of low-density lipoprotein cholesterol (LDL-c). There may be other effects called pleiotropics. OBJECTIVE: To compare the effectiveness of 2 different treatments that obtain equivalent LDL-c reductions (80 mg of simvastatin, once a day and coadministration of 10 mg of simvastatin and 10 mg of ezetimibe, once a day) over endothelial function and inflammation. METHODS: Twenty-three randomized patients with hypercholesterolemia in a 2 x 2 crossover protocol were studied. Endothelial function was analyzed by ultrasound assessment of endothelial dependent flow-mediated vasodilation of the brachial artery, and inflammation was estimated by high-sensitivity C-reactive protein (hs-CRP). RESULTS: LDL-c reduction was similar between the 2 treatments with simvastatin/ezetimibe and with simvastatin (P < 0.001); no difference between treatments was found (P = 0.968). Both treatments improved significantly the endothelial function [3.61% with simvastatin/ezetimibe (P = 0.003) and 5.08% with simvastatin (P < 0.001)]; no difference was found between the 2 treatments (P = 0.291). hs-CRP had a 23% reduction with simvastatin/ezetimibe (P = 0.004) and a 30% reduction with simvastatin alone (P = 0.01), with no significant difference between the 2 treatments (P = 0.380). CONCLUSION: The 2 forms of treatment presented similar pleiotropic effects: improvement in endothelial function and decrease in hs-CRP levels.
Assuntos
Anticolesterolemiantes/uso terapêutico , Azetidinas/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Sinvastatina/uso terapêutico , Adolescente , Adulto , Idoso , Anticolesterolemiantes/administração & dosagem , Azetidinas/administração & dosagem , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/metabolismo , Proteína C-Reativa/metabolismo , LDL-Colesterol/sangue , LDL-Colesterol/efeitos dos fármacos , Estudos Cross-Over , Quimioterapia Combinada , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Ezetimiba , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sinvastatina/administração & dosagem , Ultrassonografia , Vasodilatação/efeitos dos fármacos , Adulto JovemRESUMO
Oxidative stress is a physiological condition that is associated with atherosclerosis, and it can be influenced by diet. Our objective was to group fifty-seven individuals with dyslipidaemia controlled by statins according to four oxidative biomarkers, and to evaluate the diet pattern and blood biochemistry differences between these groups. Blood samples were collected and the following parameters were evaluated: diet intake; plasma fatty acids; lipoprotein concentration; glucose; oxidised LDL (oxLDL); malondialdehyde (MDA); total antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing ability power assays. Individuals were separated into five groups by cluster analysis. All groups showed a difference with respect to at least one of the four oxidative stress biomarkers. The separation of individuals in the first axis was based upon their total antioxidant activity. Clusters located on the right side showed higher total antioxidant activity, higher myristic fatty acid and lower arachidonic fatty acid proportions than clusters located on the left side. A negative correlation was observed between DPPH and the peroxidability index. The second axis showed differences in oxidation status as measured by MDA and oxLDL concentrations. Clusters located on the upper side showed higher oxidative status and lower HDL cholesterol concentration than clusters located on the lower side. There were no differences in diet among the five clusters. Therefore, fatty acid synthesis and HDL cholesterol concentration seem to exert a more significant effect on the oxidative conditions of the individuals with dyslipidaemia controlled by statins than does their food intake.
Assuntos
Dislipidemias/sangue , Estresse Oxidativo , Idoso , Biomarcadores/sangue , Compostos de Bifenilo/sangue , Glicemia/metabolismo , Análise por Conglomerados , Dieta , Dislipidemias/classificação , Ácidos Graxos/sangue , Feminino , Humanos , Lipoproteínas/metabolismo , Lipoproteínas LDL/sangue , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Picratos/sangueRESUMO
Fluorescent proteins from the green fluorescent protein family strongly interact with CdSe/ZnS and ZnSe/ZnS nanocrystals at neutral pH. Green emitting CdSe/ZnS nanocrystals and red emitting fluorescent protein dTomato constitute a 72% efficiency FRET system with the largest alteration of the overall photoluminescence profile, following complex formation, observed so far. The substitution of ZnSe/ZnS for CdSe/ZnS nanocrystals as energy donors enabled the use of a green fluorescent protein, GFP5, as energy acceptor. Violet emitting ZnSe/ZnS nanocrystals and green GFP5 constitute a system with 43% FRET efficiency and an unusually strong sensitized emission. ZnSe/ZnS-GFP5 provides a cadmium-free, high-contrast FRET system that covers only the high-energy part of the visible spectrum, leaving room for simultaneous use of the yellow and red color channels. Anisotropic fluorescence measurements confirmed the depolarization of GFP5 sensitized emission.