RESUMO
Age-related macular degeneration (AMD) is an eye disease that is characterized by damage to the central part of the retina, the macula, and that affects millions of people worldwide. At an advanced stage, a blind spot grows in the center of vision, severely handicapping patients with this degenerative condition. Despite therapeutic advances thanks to the use of anti-VEGF, many resistance mechanisms have been found to accentuate the visual deficit. In the present study, we explored whether supplementation with Resvega®, a nutraceutical formulation composed of omega-3 fatty acids and resveratrol, a well-known polyphenol in grapes, was able to counteract laser-induced choroidal neovascularization (CNV) in mice. We highlight that Resvega® significantly reduced CNV in mice compared with supplementations containing omega-3 or resveratrol alone. Moreover, a proteomic approach confirmed that Resvega® could counteract the progression of AMD through a pleiotropic effect targeting key regulators of neoangiogenesis in retina cells in vivo. These events were associated with an accumulation of resveratrol metabolites within the retina. Therefore, a supplementation of omega-3/resveratrol could improve the management or slow the progression of AMD in patients with this condition.
Assuntos
Neovascularização de Coroide/prevenção & controle , Suplementos Nutricionais , Ácidos Graxos Ômega-3/farmacologia , Degeneração Macular/prevenção & controle , Resveratrol/farmacologia , Animais , Neovascularização de Coroide/dietoterapia , Modelos Animais de Doenças , Ácidos Graxos Ômega-3/uso terapêutico , Feminino , Degeneração Macular/dietoterapia , Degeneração Macular/patologia , Camundongos , Proteômica , Resveratrol/uso terapêuticoRESUMO
BACKGROUND AND AIMS: Hypercholesterolemia is a major risk factor for atherosclerosis and cardiovascular diseases. Although resistant to hypercholesterolemia, the mouse is a prominent model in cardiovascular research. To assess the contribution of bile acids to this protective phenotype, we explored the impact of a 2-week-long dietary cholesterol overload on cholesterol and bile acid metabolism in mice. METHODS: Bile acid, oxysterol, and cholesterol metabolism and transport were assessed by quantitative real-time PCR, western blotting, GC-MS/MS, or enzymatic assays in the liver, the gut, the kidney, as well as in the feces, the blood, and the urine. RESULTS: Plasma triglycerides and cholesterol levels were unchanged in mice fed a cholesterol-rich diet that contained 100-fold more cholesterol than the standard diet. In the liver, oxysterol-mediated LXR activation stimulated the synthesis of bile acids and in particular increased the levels of hydrophilic muricholic acids, which in turn reduced FXR signaling, as assessed in vivo with Fxr reporter mice. Consequently, biliary and basolateral excretions of bile acids and cholesterol were increased, whereas portal uptake was reduced. Furthermore, we observed a reduction in intestinal and renal bile acid absorption. CONCLUSIONS: These coordinated events are mediated by increased muricholic acid levels which inhibit FXR signaling in favor of LXR and SREBP2 signaling to promote efficient fecal and urinary elimination of cholesterol and neo-synthesized bile acids. Therefore, our data suggest that enhancement of the hydrophilic bile acid pool following a cholesterol overload may contribute to the resistance to hypercholesterolemia in mice. This work paves the way for new therapeutic opportunities using hydrophilic bile acid supplementation to mitigate hypercholesterolemia.
Assuntos
Ácidos e Sais Biliares/metabolismo , Colesterol na Dieta/efeitos adversos , Ácidos Cólicos/uso terapêutico , Hipercolesterolemia/prevenção & controle , Animais , Colesterol na Dieta/metabolismo , Avaliação Pré-Clínica de Medicamentos , Hipercolesterolemia/etiologia , Masculino , Camundongos Endogâmicos C57BL , Receptores Citoplasmáticos e Nucleares/metabolismoRESUMO
Age-related macular degeneration (AMD) is one of the main causes of deterioration in vision in adults aged 55 and older. In spite of therapies, the progression of the disease is often observed without reverse vision quality. In the present study, we explored whether, in undifferentiated ARPE-19 retinal cells, a disruption of the VEGF receptors (VEGF-R)/caveolin-1 (Cav-1)/protein kinases pathway could be a target for counteracting VEGF secretion. We highlight that Resvega®, a combination of omega-3 fatty acids with an antioxidant, resveratrol, inhibits VEGF-A secretion in vitro by disrupting the dissociation of the VEGF-R2/Cav-1 complex into rafts and subsequently preventing MAPK activation. Moreover, DNA ChIP analysis reveals that this combination prevents the interaction between AP-1 and vegf-a and vegf-r2 gene promoters. By these pathways, Resvega could present a potential interest as nutritional complementation against AMD.
Assuntos
Caveolina 1/metabolismo , Degeneração Macular/prevenção & controle , Retina/efeitos dos fármacos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Retina/metabolismo , Fator de Transcrição AP-1/antagonistas & inibidoresRESUMO
BACKGROUND: LPS-type endotoxins, naturally found in the gut microbiota, are recognized as triggers of inflammation and emerge as detrimental factors of healthy aging. Nutrition represents a promising strategy to reduce LPS burden, yet little is known about the relation of diet to circulating LPS concentrations. OBJECTIVE: The aim was to evaluate the associations between food groups, dietary patterns, and circulating 3-hydroxy fatty acids (3-OH FAs), a proxy of LPS burden. METHODS: In a cross-sectional study of 698 French older community-dwelling individuals, 3-OH FA concentrations were measured by LC-tandem MS. Dietary patterns were determined using food-frequency questionnaires. Adherence to a Mediterranean-type diet was computed according to the consumption of 8 food groups (fruits, vegetables, legumes, cereals, fish, olive oil, meat, and dairy products) and alcohol intake (range: 0, low adherence, to 18, high adherence). Three a posteriori dietary patterns were derived from factor analysis: complex carbohydrate (rich in rice, pasta, eggs, poultry, and potatoes), traditional (rich in alcohol, meat, processed meats-cold cuts, and legumes), and prudent (rich in vegetables and fruits and low in cookies) diets. Linear regression models were applied. RESULTS: The frequency of consumption of each food group was not associated with 3-OH FA concentrations. Greater adherence to both the Mediterranean diet and the prudent diet were associated with lower circulating 3-OH FAs (ß [95% CI] for each additional point of score: -0.12 [-0.22, -0.01] and -0.27 [-0.48, -0.07], respectively). In contrast, greater adherence to the traditional diet was associated with higher concentration of 3-OH FAs (ß [95% CI] 0.22 [0.001, 0.46]). The adherence to the complex-carbohydrate diet was not associated with 3-OH FA concentrations. CONCLUSIONS: Based on 2 complementary approaches, the identified plant-based dietary patterns were associated with lower 3-OH FA concentrations, and thus a lower LPS burden, which is considered a potent trigger of inflammatory response.
Assuntos
Dieta Saudável , Dieta Mediterrânea , Ácidos Graxos/sangue , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Ácidos Graxos/química , Ácidos Graxos/classificação , França , Humanos , Lipopolissacarídeos , Fatores de RiscoRESUMO
Limitation of 5-fluorouracil (5-FU) anticancer efficacy is due to IL-1ß secretion by myeloid-derived suppressor cells (MDSC), according to a previous pre-clinical report. Release of mature IL-1ß is a consequence of 5-FU-mediated NLRP3 activation and subsequent caspase-1 activity in MDSC. IL-1ß sustains tumor growth recovery in 5-FU-treated mice. Docosahexaenoic acid (DHA) belongs to omega-3 fatty acid family and harbors both anticancer and anti-inflammatory properties, which could improve 5-FU chemotherapy. Here, we demonstrate that DHA inhibits 5-FU-induced IL-1ß secretion and caspase-1 activity in a MDSC cell line (MSC-2). Accordingly, we showed that DHA-enriched diet reduces circulating IL-1ß concentration and tumor recurrence in 5-FU-treated tumor-bearing mice. Treatment with 5-FU led to JNK activation through ROS production in MDSC. JNK inhibitor SP600125 as well as DHA-mediated JNK inactivation decreased IL-1ß secretion. The repression of 5-FU-induced caspase-1 activity by DHA supplementation is partially due to ß-arrestin-2-dependent inhibition of NLRP3 inflammasome activity but was independent of JNK pathway. Interestingly, we showed that DHA, through ß-arrestin-2-mediated inhibition of JNK pathway, reduces V5-tagged mature IL-1ß release induced by 5-FU, in MDSC stably overexpressing a V5-tagged mature IL-1ß form. Finally, we found a negative correlation between DHA content in plasma and the induction of caspase-1 activity in HLA-DR- CD33+ CD15+ MDSC of patients treated with 5-FU-based chemotherapy, strongly suggesting that our data are clinical relevant. Together, these data provide new insights on the regulation of IL-1ß secretion by DHA and on its potential benefit in 5-FU-based chemotherapy.
Assuntos
Ácidos Docosa-Hexaenoicos/farmacologia , Fluoruracila/farmacologia , Inflamassomos/efeitos dos fármacos , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Caspase 1/metabolismo , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Ácidos Docosa-Hexaenoicos/uso terapêutico , Feminino , Fluoruracila/uso terapêutico , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , beta-Arrestina 2/metabolismoRESUMO
Obesity may not be consistently associated with metabolic disorders and mortality later in life, prompting exploration of the challenging concept of healthy obesity. Here, the consumption of a high-fat/high-sucrose (HF/HS) diet produces hyperglycaemia and hypercholesterolaemia, increases oxidative stress, increases endotoxaemia, expands adipose tissue (with enlarged adipocytes, enhanced macrophage infiltration and the accumulation of cholesterol and oxysterols), and reduces the median lifespan of obese mice. Despite the persistence of obesity, supplementation with a polyphenol-rich plant extract (PRPE) improves plasma lipid levels and endotoxaemia, prevents macrophage recruitment to adipose tissues, reduces adipose accumulation of cholesterol and cholesterol oxides, and extends the median lifespan. PRPE drives the normalization of the HF/HS-mediated functional enrichment of genes associated with immunity and inflammation (in particular the response to lipopolysaccharides). The long-term limitation of immune cell infiltration in adipose tissue by PRPE increases the lifespan through a mechanism independent of body weight and fat storage and constitutes the hallmark of a healthy adiposity trait.
Assuntos
Adiposidade/efeitos dos fármacos , Dieta , Longevidade/efeitos dos fármacos , Obesidade/patologia , Obesidade/fisiopatologia , Extratos Vegetais/farmacologia , Polifenóis/análise , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/patologia , Animais , Regulação para Baixo/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Extratos Vegetais/químicaRESUMO
The worldwide prevalence of metabolic diseases is increasing, and there are global recommendations to limit consumption of certain nutrients, especially saturated lipids. Insulin resistance, a common trait occurring in obesity and type 2 diabetes, is associated with intestinal lipoprotein overproduction. However, the mechanisms by which the intestine develops insulin resistance in response to lipid overload remain unknown. Here, we show that insulin inhibits triglyceride secretion and intestinal microsomal triglyceride transfer protein expression in vivo in healthy mice force-fed monounsaturated fatty acid-rich olive oil but not in mice force-fed saturated fatty acid-rich palm oil. Moreover, when mouse intestine and human Caco-2/TC7 enterocytes were treated with the saturated fatty acid, palmitic acid, the insulin-signaling pathway was impaired. We show that palmitic acid or palm oil increases ceramide production in intestinal cells and that treatment with a ceramide analogue partially reproduces the effects of palmitic acid on insulin signaling. In Caco-2/TC7 enterocytes, ceramide effects on insulin-dependent AKT phosphorylation are mediated by protein kinase C but not by protein phosphatase 2A. Finally, inhibiting de novo ceramide synthesis improves the response of palmitic acid-treated Caco-2/TC7 enterocytes to insulin. These results demonstrate that a palmitic acid-ceramide pathway accounts for impaired intestinal insulin sensitivity, which occurs within several hours following initial lipid exposure.