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Environmental enteric dysfunction (EED) is an inflammatory syndrome postulated to contribute to stunted child growth and to be associated with intestinal dysbiosis and nutrient malabsorption. However, the small intestinal contributions to EED remain poorly understood. This study aimed to assess changes in the proximal and distal intestinal microbiota in the context of stunting and EED and to test for a causal role of these bacterial isolates in the underlying pathophysiology. We performed a cross-sectional study in two African countries recruiting roughly 1,000 children aged 2 to 5 years and assessed the microbiota in the stomach, duodenum, and feces. Upper gastrointestinal samples were obtained from stunted children and stratified according to stunting severity. Fecal samples were collected. We then investigated the role of clinical isolates in EED pathophysiology using tissue culture and animal models. We find that small intestinal bacterial overgrowth (SIBO) is extremely common (>80%) in stunted children. SIBO is frequently characterized by an overgrowth of oral bacteria, leading to increased permeability and inflammation and to replacement of classical small intestinal strains. These duodenal bacterial isolates decrease lipid absorption in both cultured enterocytes and mice, providing a mechanism by which they may exacerbate EED and stunting. Further, we find a specific fecal signature associated with the EED markers fecal calprotectin and alpha-antitrypsin. Our study shows a causal implication of ectopic colonization of oral bacterial isolated from the small intestine in nutrient malabsorption and gut leakiness in vitro. These findings have important therapeutic implications for modulating the microbiota through microbiota-targeted interventions.
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Microbioma Gastrointestinal , Transtornos do Crescimento , Intestino Delgado , Lipídeos , Boca , Animais , Bactérias , Pré-Escolar , Estudos Transversais , Transtornos do Crescimento/etiologia , Humanos , Complexo Antígeno L1 Leucocitário , Metabolismo dos Lipídeos , Síndromes de Malabsorção , Camundongos , Modelos Teóricos , Boca/microbiologiaRESUMO
Adipose tissue dysfunction is a key mechanism that leads to adiposity-based chronic disease. This study aimed to investigate the reliability of the adiponectin/leptin ratio (AdipoQ/Lep) as an adipose tissue and metabolic function biomarker in adults with obesity, without diabetes. Data were collected from a clinical trial conducted in 28 adults with obesity (mean body mass index: 35.4 ± 3.7 kg/m2) (NCT02169778). With the use of a forward stepwise multiple linear regression model to explore the relationship between AdipoQ/Lep and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), it was observed that 48.6% of HOMA-IR variance was explained by triacylglycerols, AdipoQ/Lep, and waist-to-hip ratio (P < 0.001), AdipoQ/Lep being the strongest independent predictor (Beta = -0.449, P < 0.001). A lower AdipoQ/Lep was correlated with higher body mass index (Rs = -0.490, P < 0.001), body fat mass (Rs = -0.486, P < 0.001), waist-to-height ratio (Rs = -0.290, P = 0.037), and plasma resistin (Rs = -0.365, P = 0.009). These data highlight the central role of adipocyte dysfunction in the pathogenesis of insulin resistance and emphasize that AdipoQ/Lep may be a promising early marker of insulin resistance development in adults with obesity.NEW & NOTEWORTHY Adiponectin/leptin ratio, triacylglycerols, and waist-to-hip ratio explained almost half of HOMA-IR variance in the context of obesity. This study provides evidence to support adipose tissue dysfunction as a central feature of the pathophysiology of obesity and insulin resistance. Early identification of individuals at higher risk of developing metabolic complications through adipose tissue dysfunction assessment and the staging of obesity and its transient phenotypes can contribute to improve therapeutic decision-making.
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Resistência à Insulina , Leptina , Humanos , Leptina/metabolismo , Adiponectina/metabolismo , Resistência à Insulina/fisiologia , Reprodutibilidade dos Testes , Obesidade/metabolismo , Índice de Massa Corporal , TriglicerídeosRESUMO
This work aimed to characterize the uptake of folate and glucose by breast cancer cells and to study the effect of lactate upon the transport of these nutrients and upon cell viability, proliferation and migration capacity. Data obtained showed that: a) MCF7 cells uptake (3)H-folic acid ((3)H-FA) at physiological but not at acidic pH; b) T47D cells accumulate (3)H-FA and (14)C-5-methyltetrahydrofolate ((14)C-5-MTHF) more efficiently at acidic than at physiological pH; c) (3)H-deoxyglucose ((3)H-DG) uptake by T47D cells is sodium-independent, inhibited by cytochalasin B (CYT B) and stimulated by insulin. Regarding the effect of lactate, in T47D cells, acute (26 min) and chronic (24 h) exposure to lactic acid (LA) stimulated (3)H-FA uptake. Acute exposure to LA also stimulated (3)H-DG uptake and chronic exposure to LA significantly stimulated T47D cell migratory capacity. In conclusion, the transport of folates is strikingly different in two phenotypically similar breast cancer cell lines: MCF7 and T47D cells. Additionally, lactate seems to act as a signaling molecule which increases the uptake of nutrients and promotes the migration capacity of T47D cells.
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Neoplasias da Mama/metabolismo , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Ácido Láctico/metabolismo , Transporte Biológico/fisiologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Ácido Fólico/metabolismo , Glucose/metabolismo , HumanosRESUMO
In this study, we aimed to investigate modulation of glucose uptake by the HTR-8/SVneo human first-trimester extravillous trophoblast cell line by a series of compounds and to study its consequences upon cell proliferation, viability and migration. We observed that uptake of (3)H-deoxy-d-glucose ((3)H-DG; 10 nM) was time-dependent, saturable, inhibited by cytochalasin B (50 and 100 µM), phloretin (0.5 mM) and phloridzin (1 mM), insulin-insensitive and sodium-independent. In the short term (30 min), neither 5-HT (100-1000 µM), melatonin (10 nM) nor the drugs of abuse ethanol (100 mM), nicotine (100 µM), cocaine (25 µM), amphetamine (10-25 µM) and 3,4-methylenedioxy-N-methamphetamine (10 µM) affected (3)H-DG uptake, while dexamethasone (100-1000 µM), fluoxetine (100-300 µM), quercetin, epigallocatechin-3-gallate (30-1000 µM), xanthohumol (XH) and resveratrol (1-500 µM) decreased it. XH was the most potent inhibitor [IC50 = 3.55 (1.37-9.20) µM] of (3)H-DG uptake, behaving as a non-competitive inhibitor of (3)H-DG uptake, both after short- and long-term (24 h) treatment. The effect of XH (5 µM; 24 h) upon (3)H-DG uptake involved mammalian target of rapamycin, tyrosine kinases and c-Jun N-terminal kinases intracellular pathways. Moreover, XH appeared to decrease cellular uptake of lactate due to inhibition of the monocarboxylate transporter 1. Additionally, XH (24 h; 5 µM) decreased cell viability, proliferation, culture growth and migration. The effects of XH upon cell viability and culture growth, but not the antimigratory effect, were mimicked by low extracellular glucose conditions and reversed by high extracellular glucose conditions. We thus suggest that XH, by inhibiting glucose cellular uptake and impairing HTR-8/SVneo cell viability and proliferation, may have a deleterious impact in the process of placentation.
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Desoxiglucose/metabolismo , Flavonoides/farmacologia , Proteínas Facilitadoras de Transporte de Glucose/antagonistas & inibidores , Placentação/efeitos dos fármacos , Propiofenonas/farmacologia , Trofoblastos/efeitos dos fármacos , Transporte Biológico/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular Transformada , Movimento Celular/efeitos dos fármacos , Citocalasina B/farmacologia , Citocalasina B/toxicidade , Dexametasona/farmacologia , Dexametasona/toxicidade , Feminino , Flavonoides/toxicidade , Glucose/farmacologia , Proteínas Facilitadoras de Transporte de Glucose/fisiologia , Humanos , Drogas Ilícitas/farmacologia , Drogas Ilícitas/toxicidade , Melatonina/farmacologia , Melatonina/toxicidade , Floretina/farmacologia , Floretina/toxicidade , Florizina/farmacologia , Florizina/toxicidade , Polifenóis/farmacologia , Polifenóis/toxicidade , Gravidez , Primeiro Trimestre da Gravidez , Propiofenonas/toxicidade , Proteínas Tirosina Quinases/fisiologia , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Estilbenos/farmacologia , Estilbenos/toxicidade , Serina-Treonina Quinases TOR/fisiologia , Trofoblastos/citologiaRESUMO
Our aim was to investigate the effect of several dietary polyphenols on glucose uptake by breast cancer cells. Uptake of (3)H-deoxy-D-glucose ((3)H-DG) by MCF-7 cells was time-dependent, saturable, and inhibited by cytochalasin B plus phloridzin. In the short-term (26 min), myricetin, chrysin, genistein, resveratrol, kaempferol, and xanthohumol (10-100 µM) inhibited (3)H-DG uptake. Kaempferol was found to be the most potent inhibitor of (3)H-DG uptake [IC50 of 4 µM (1.6-9.8)], behaving as a mixed-type inhibitor. In the long-term (24 h), kaempferol (30 µM) was also able to inhibit (3)H-DG uptake, associated with a 40% decrease in GLUT1 mRNA levels. Interestingly enough, kaempferol (100 µM) revealed antiproliferative (sulforhodamine B and (3)H-thymidine incorporation assays) and cytotoxic (extracellular lactate dehydrogenase activity determination) properties, which were mimicked by low extracellular (1 mM) glucose conditions and reversed by high extracellular (20 mM) glucose conditions. Finally, exposure of cells to kaempferol (30 µM) induced an increase in extracellular lactate levels over time (to 731 ± 32% of control after a 24 h exposure), due to inhibition of MCT1-mediated lactate cellular uptake. In conclusion, kaempferol potently inhibits glucose uptake by MCF-7 cells, apparently by decreasing GLUT1-mediated glucose uptake. The antiproliferative and cytotoxic effect of kaempferol in these cells appears to be dependent on this effect.
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Anticarcinógenos/farmacologia , Glucose/metabolismo , Quempferóis/farmacologia , Feminino , Transportador de Glucose Tipo 1/fisiologia , Humanos , Células MCF-7 , Transportadores de Ácidos Monocarboxílicos/antagonistas & inibidores , Transportadores de Ácidos Monocarboxílicos/fisiologia , Polifenóis/farmacologia , Simportadores/antagonistas & inibidores , Simportadores/fisiologiaRESUMO
Gut dysbiosis has been recently recognized as a hallmark of ageing. At this stage of life, gut microbiota becomes depleted from bacteria involved in the production of short-chain fatty acids (SCFA), indole and its derivative indole-3-propionic acid (IPA), metabolites shown to improve host glycemic control as well as insulin sensitivity and secretion. Moreover, gut microbiota becomes enriched in pathobiont bacteria involved in the production of imidazole propionate, phenols and trimethylamine, metabolites that promote host insulin resistance and atherosclerosis. The magnitude of these changes is much more pronounced in unhealthy than in healthy ageing. On the other hand, a distinct gut microbiota signature is displayed during longevity, the most prominent being an enrichment in both SCFA and IPA bacterial producers. This short Review discusses, in an innovative and integrative way, cutting-edge research on the composition of gut microorganisms and profile of metabolites secreted by them, that are associated with a healthy and unhealthy ageing pattern and with longevity. A detailed description of the positive or detrimental metabolic effects, in the ageing host, of diet-derived gut microbial metabolites is provided. Finally, microbiota-targeted interventions that counteract gut dysbiosis associated with ageing, are briefly outlined.
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BACKGROUND: The mechanisms whereby gestational diabetes mellitus (GDM) increases the risk of fetal overgrowth and development of metabolic diseases later in life are likely to involve changes in nutrient supply to the fetus. Hence, in this work, we hypothesize that GDM may affect folic acid (FA) supply to the placenta and fetus. METHODS: We compared (3)H-FA uptake by human cytotrophoblasts isolated from normal pregnancies (normal trophoblasts; NTB cells) and GDM pregnancies (diabetic trophoblasts; DTB cells) and investigated the effect of GDM hallmarks on (3)H-FA uptake by BeWo cells. RESULTS: (3)H-FA uptake by NTB and DTB cells was time dependent and acidic pH stimulated. When compared with NTB, (3)H-FA uptake by DTB cells was more sensitive to acidic pH changes and to 5-methyltetrahydrofolate and pemetrexed (PTX) inhibition, indicating a proportionally greater involvement of the proton-coupled folate transporter (PCFT). A 4-h exposure of BeWo cells to lipopolysaccharide (LPS, 1-10 µg/ml) or to high levels of tumor necrosis factor-α (TNF-α, 300 ng/l) significantly reduced (3)H-FA uptake. Moreover, hyperleptinemic conditions (100 ng/ml leptin) decreased (3)H-FA uptake by BeWo cells in a time-dependent manner when compared with normoleptinemic conditions (1 ng/ml leptin). CONCLUSION: GDM modulates (3)H-FA uptake by the syncytiotrophoblast, and leptin as well as TNF-α downregulate it.
Assuntos
Diabetes Gestacional/metabolismo , Ácido Fólico/metabolismo , Mediadores da Inflamação/metabolismo , Leptina/metabolismo , Trofoblastos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Transporte Biológico , Estudos de Casos e Controles , Células Cultivadas , Diabetes Gestacional/sangue , Feminino , Glutamatos/farmacologia , Guanina/análogos & derivados , Guanina/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Cinética , Lipopolissacarídeos/farmacologia , Pemetrexede , Gravidez , Transportador de Folato Acoplado a Próton/antagonistas & inibidores , Transportador de Folato Acoplado a Próton/metabolismo , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Tetra-Hidrofolatos/farmacologia , Trofoblastos/efeitos dos fármacosRESUMO
Background and Aims: Although gut inflammation and dysbiosis have been implicated in the pathophysiology of severe cases of coronavirus disease 2019 (COVID-19), the role of intestinal anti-inflammatory enzymes, such as alkaline phosphatase, is still underexplored. Therefore, the aim of this study was to compare intestinal alkaline phosphatase (iALP) activity and its proinflammatory substrate - bacterial lipopolysaccharide (LPS) - concentration between mild-to-moderate and severe COVID-19 patients. Methods: Stool samples collected from 53 mild-to-moderate and 57 severe adult COVID-19 patients, previously enrolled in a national multicentre cross-sectional study (NCT04355741), were analysed for iALP activity and LPS concentration. Results: iALP activity decreased by 40% in severe compared to mild-to-moderate COVID-19 patients (median [interquartile range] of 120.6 [25.2-593.1] nmol pNP/min/g of protein vs 202.8 [102.1-676.1] nmol pNP/min/g of protein; P = .04) after adjustment for clinical and gut microbiota parameters. Regarding fecal LPS, its concentration was found to be decreased in severe patients (mean ± standard error of mean of 18,118 ± 1225 EU/g of feces vs 22,508 ± 1203 EU/g of feces; P = .01), although this parameter did not correlate with plasma levels of C-reactive protein (P = .08), a sensitive biomarker of systemic inflammation. In contrast, fecal ALP activity / LPS concentration ratio, an indicator of iALP efficiency, was found to be increased in severe compared to mild-to-moderate COVID-19 patients (P = .04). Conclusion: Changes in iALP kinetic parameters found in severe COVID-19 patients may represent a potential mechanism to counterbalance alterations in gut homeostasis (eg inflammation and dysbiosis) associated with COVID-19 severity.
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Although elevated blood levels of trimethylamine N-oxide (TMAO) have been associated with atherosclerosis development in humans, the role of its gut microbiota-derived precursor, TMA, in this process has not been yet deciphered. Taking this into account, and the fact that increased intestinal fatty acid absorption contributes to atherosclerosis onset and progression, this study aimed to evaluate the effect of TMA on fatty acid absorption in a cell line that mimics human enterocytes. Caco-2 cells were treated with TMA 250 µM for 24 h. Fatty acid absorption was assessed by measuring the apical-to-basolateral transport and the intracellular levels of BODIPY-C12, a fluorescently labelled fatty acid analogue. Gene expression of the main intestinal fatty acid transporters was evaluated by real-time quantitative reverse transcription PCR. Compared to control conditions, TMA increased, in a time-dependent manner and by 20-50 %, the apical-to-basolateral transport and intracellular levels of BODIPY-C12 fatty acid in Caco-2 cells. Fatty acid transport protein 4 (FATP4) and fatty acid translocase (FAT)/CD36 gene expression were not stimulated by TMA, suggesting that TMA-induced increase in fatty acid transport may be mediated by an increase in FAT/CD36 and/or FATP4 activity and/or fatty acid passive transport. This study demonstrated that TMA increases the intestinal absorption of fatty acids. Future studies are necessary to confirm if this may constitute a novel mechanism that partially explains the existing positive association between the consumption of a diet rich in TMA sources (e.g. red meat) and the increased risk of atherosclerotic diseases.
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Aterosclerose , Compostos de Boro , Ácidos Graxos , Metilaminas , Humanos , Ácidos Graxos/farmacologia , Ácidos Graxos/metabolismo , Células CACO-2 , Absorção Intestinal , Antígenos CD36 , Técnicas de Cultura de CélulasRESUMO
Clotrimazole has anticarcinogenic activity in several cell types. Our aims were to investigate the anticarcinogenic effect of clotrimazole in a tumoral intestinal epithelial (Caco-2) cell line, to compare it with the effect in a nontumoral intestinal epithelial cell line (IEC-6 cells), and to investigate inhibition of energy substrate uptake as a mechanism contributing to it. The effect of clotrimazole on cell proliferation, viability and differentiation, H-deoxyglucose (H-DG), H-O-methyl-glucose (H-OMG), and C-butyrate uptake, as well as mRNA expression levels of glucose transporters was assessed. In Caco-2 cells, clotrimazole decreased cellular viability and proliferation and increased cell differentiation. The effect on cell proliferation and viability was potentiated by rhodamine123. Clotrimazole also decreased cellular viability and proliferation in IEC-6 cells, but increased the cellular DNA synthesis rate and had no effect on cell differentiation. Exposure of Caco-2 cells to clotrimazole (10 µmol/l) for 1 and 7 days increased (by 20-30%) the uptake of H-DG and H-OMG, respectively, but had no effect on C-butyrate uptake. The effect on H-DG and H-OMG transport was maximal at 10 µmol/l, and the pharmacological characteristics of transport were not changed. However, clotrimazole changed the mRNA expression levels of the facilitative glucose transporter 2 and the Na-dependent glucose cotransporter. Clotrimazole exhibits comparable cytotoxic effects in tumoral and nontumoral intestinal epithelial cell lines. In Caco-2 cells, the cytotoxic effect of clotrimazole was strongly potentiated by the inhibition of oxidative phosphorylation. Moreover, stimulation of glucose uptake might be a compensation mechanism in response to the glycolysis inhibition caused by clotrimazole.
Assuntos
Antineoplásicos/farmacologia , Clotrimazol/farmacologia , Metabolismo Energético/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Mucosa Intestinal/efeitos dos fármacos , 3-O-Metilglucose/metabolismo , Butiratos/metabolismo , Células CACO-2 , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA/biossíntese , Desoxiglucose/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Proteínas Facilitadoras de Transporte de Glucose/genética , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Fosforilação Oxidativa , Rodamina 123/farmacologiaRESUMO
Folic acid (FA) is a vitamin essential for normal cellular functions, growth, and development. Because humans cannot synthesize this micronutrient, it must be obtained from dietary sources through intestinal absorption. The intestinal tract is a major target for oxidative stress. Our aim was to investigate the effect of oxidative stress upon the uptake of FA by Caco-2 cells. Oxidative stress was induced by exposure of the cells to tert-butyl hydroperoxide (TBH) for 1 h. TBH (3,000 µM) induced an increase in biomarkers of oxidative stress, while maintaining cell viability and proliferation. In relation to the apical uptake of (3)H-FA, TBH (3,000 µM) reduced the cellular accumulation of (3)H-FA (10 nM), although the characteristics (kinetics, pH dependence, and inhibitory profile) of (3)H-FA uptake were not changed. This effect was associated with a decrease in the mRNA steady-state levels of proton-coupled folate transporter and folate receptor alpha and of the efflux transporter multidrug resistance protein 2. Moreover, TBH (3,000 µM) did not affect the noncarrier-mediated apical uptake of (3)H-FA. Finally, the effect of TBH upon (3)H-FA apical uptake was not dependent on protein kinase A, protein kinase C, mitogen-activated protein kinases, phosphoinositide 3-kinase, nuclear factor kappa B, and protein tyrosine kinases, but was completely prevented by dietary polyphenols (resveratrol, quercetin, and EGCG). These results suggest that oxidative stress at the intestinal level may result in a reduction in the intestinal absorption of dietary FA and that polyphenolic dietary components may offer protection against oxidative stress-induced inhibition of intestinal FA absorption.
Assuntos
Ácido Fólico/metabolismo , Absorção Intestinal , Mucosa Intestinal/metabolismo , Estresse Oxidativo , 1-Fosfatidilinositol 4-Quinase/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Transporte Biológico/efeitos dos fármacos , Células CACO-2 , Proliferação de Células , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Receptor 1 de Folato/genética , Humanos , Absorção Intestinal/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Moduladores de Transporte de Membrana/farmacologia , Proteínas de Membrana Transportadoras/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Polifenóis/farmacologia , Proteína Quinase C/metabolismo , Proteínas Tirosina Quinases/metabolismo , Transportador de Folato Acoplado a Próton/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , terc-Butil Hidroperóxido , Membro 4 da Subfamília B de Transportadores de Cassetes de Ligação de ATPRESUMO
Intestinal alkaline phosphatase (IALP) has recently assumed a special relevance, being the subject of study in the prevention and treatment of certain diseases related to leaky gut. This brush border enzyme (ecto-enzyme) plays an important role in the maintenance of intestinal microbial homeostasis and intestinal barrier function through its ability to dephosphorylate lipopolysaccharide (LPS). This review addresses how IALP and intestinal barrier dysfunction may be implicated in the pathophysiology of specific diseases such as inflammatory bowel disease, necrotizing enterocolitis, and metabolic syndrome. The use of IALP as a possible biomarker to assess intestinal barrier function and strategies to modulate IALP activity are also discussed.
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BACKGROUND & AIMS: Although intermittent energy restriction (IER) seems to be as effective as continuous energy restriction (CER) for weight loss, there is still a need to determine the putative effect of this strategy upon the metabolic-inflammatory status. This study aimed to compare the effects of IER versus CER on cardiometabolic and inflammatory markers, over a 12-week period, in adults with obesity. METHODS: Twenty-eight Norwegian adults (20-55 years) with obesity [body mass index: 35.4 (3.7) kg/m2] from a clinical trial (NCT02169778) who completed a 12-weeks diet-induced weight loss as IER (n = 14) or CER (n = 14) were included in this study. Cardiometabolic, adipokines and inflammatory markers were evaluated at baseline and after the intervention. Plasma levels of 13 inflammatory cytokines and chemokines (IL-1ß, IFN-α2, IFN-γ, TNF-α, MCP-1, IL-6, IL-8, IL-10, IL-12, IL-17A, IL-18, IL-23, and IL-33) and 4 adipokines (adiponectin, adipsin, leptin and resistin) were measured through multiplex bead-based flow cytometric immunoassays. RESULTS: Both interventions resulted in comparable reductions in fasting glucose and insulin concentrations, lipid profile biomarkers, and adipokines. There were significant differences in HOMA-IR between interventions, with a more pronounced reduction in the IER group (-3.7 vs -1.6, P = 0.040). Inflammatory cytokines and chemokines decreased significantly in the IER group only. Differences in the relative changes of IL-1ß (-48.5 vs 58.2%, P = 0.011), IFN-γ (-53.2 vs 45.1%, P = 0.023), MCP-1 (-22.0 vs 17.4%, P = 0.023), IL-18 (-40.8 vs 10.1%, P = 0.019), IL-23 (-64.8 vs 44.0%, P = 0.011) and IL-33 (-53.4 vs 35.7%, P = 0.028) were statistically significant between groups, with improvements in the inflammatory profile in the IER group. CONCLUSIONS: Our results suggest that a 12-weeks intermittent energy restriction, in comparison to a continuous energy strategy, could be advantageous to reduce inflammation associated with obesity, and consequently improve insulin resistance, regardless of the amount of weight loss. Registered under ClinicalTrials.gov Identifier no. NCT02169778.
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Doenças Cardiovasculares , Interleucina-33 , Adipocinas , Tecido Adiposo , Adulto , Restrição Calórica/métodos , Ingestão de Energia , Humanos , Inflamação , Interleucina-18 , Interleucina-23 , Obesidade/terapia , Redução de PesoRESUMO
Butyrate (BT) is one of the main end products of anaerobic bacterial fermentation of dietary fiber within the human colon. Among its recognized effects, BT inhibits colon carcinogenesis. Our aim was to characterize uptake of BT by two nontransformed intestinal epithelial cell lines: rat small intestinal epithelial (IEC-6) and fetal human colonic epithelial (FHC) cells. Uptake of ¹4C-BT by IEC-6 cells was (1) time- and concentration-dependent; (2) pH-dependent; (3) Na+-, Clâ»- and energy-dependent; (4) inhibited by BT structural analogues; (5) sensitive to monocarboxylate transporter 1 (MCT1) inhibitors; and (6) insensitive to DIDS and amiloride. IEC-6 cells express both MCT1 and Na+-coupled monocarboxylate transporter 1 (SMCT1) mRNA. We conclude that ¹4C-BT uptake by IEC-6 cells mainly involves MCT1, with a small contribution of SMCT1. Acute exposure to ethanol, acetaldehyde, indomethacin, resveratrol and quercetin reduced ¹4C-BT uptake. Chronic exposure to resveratrol and quercetin reduced ¹4C-BT uptake but had no effect on either MCT1 or SMCT1 mRNA levels. Uptake of ¹4C-BT by FHC cells was time- and concentration-dependent but pH-, Na+-, Clâ»- and energy-independent and insensitive to BT structural analogues and MCT1 inhibitors. Although MCT1 (but not SMCT1) mRNA expression was found in FHC cells, the characteristics of ¹4C-BT uptake by FHC cells did not support either MCT1 or SMCT1 involvement. In conclusion, uptake characteristics of ¹4C-BT differ between IEC-6 and FHC cells. IEC-6 cells demonstrate MCT1- and SMCT1-mediated transport, while FHC cells do not.
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Butiratos/metabolismo , Carbono/metabolismo , Células Epiteliais/metabolismo , Mucosa Intestinal/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Amilorida/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Transporte Biológico/fisiologia , Linhagem Celular , Colo/metabolismo , Células Epiteliais/citologia , Feminino , Feto , Expressão Gênica , Humanos , Concentração de Íons de Hidrogênio , Mucosa Intestinal/citologia , Íons/metabolismo , Cinética , Transportadores de Ácidos Monocarboxílicos/genética , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Traçadores Radioativos , Ratos , Bloqueadores dos Canais de Sódio/farmacologia , Especificidade da Espécie , Simportadores/genética , Simportadores/metabolismoRESUMO
Our aim was to investigate the effect of several dietary polyphenols on uptake of (14)C-butyrate ((14)C-BT) by Caco-2 cells and try to correlate this effect with the modulation of the anticarcinogenic effect of BT in these cells. Acutely, uptake of (14)C-BT (10 µM) was decreased by resveratrol, quercetin, myricetin, and chrysin, and increased by xanthohumol, catechin, and epicatechin; and uptake of (14)C-BT (20 mM) was reduced by resveratrol, quercetin, myricetin, chrysin, EGCG, and epicatechin. Resveratrol acts as a competitive inhibitor of (14)C-BT uptake. Chronically, quercetin and EGCG increased uptake of (14)C-BT (10 µM), whereas myricetin, rutin, chrysin, and xanthohumol decreased it. Moreover, catechin (1 µM), quercetin, myricetin, rutin, EGCG, and chrysin increased uptake of (14)C-BT (20 mM), whereas catechin (0.1 µM) decreased it. EGCG, myricetin, and catechin decreased MCT1 mRNA expression, while chrysin increased it; quercetin, rutin, and xanthohumol had no effect. BT (5 mM; 48 h) markedly decreased cellular viability and proliferation and increased cell differentiation and apoptosis. In general, combination of polyphenolic compounds with BT did not significantly modify these changes. In conclusion, changes in uptake of BT induced by polyphenols do not correlate with changes on the effect of BT upon cell viability, cell proliferation, differentiation, and apoptosis.
Assuntos
Apoptose/efeitos dos fármacos , Butiratos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Flavonoides/farmacologia , Fenóis/farmacologia , Análise de Variância , Anticarcinógenos , Células CACO-2 , Catequina/análogos & derivados , Catequina/farmacologia , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Humanos , Polifenóis , Propiofenonas/farmacologia , Quercetina/farmacologia , Análise de Regressão , Resveratrol , Rutina/farmacologia , Estilbenos/farmacologiaRESUMO
The Mediterranean diet (MD) has been recommended for type 2 diabetes (T2D) treatment. The impact of diet in shaping the gut microbiota is well known, particularly for MD. However, the link between MD and diabetes outcome improvement is not completely clear. This study aims to evaluate the role of microbiota modulation by a nonpharmacological intervention in patients with T2D. In this 12-week single-arm pilot study, nine participants received individual nutritional counseling sessions promoting MD. Gut microbiota, biochemical parameters, body composition, and blood pressure were assessed at baseline, 4 weeks, and 12 weeks after the intervention. Adherence to MD [assessed by Mediterranean Diet Adherence Screener (MEDAS) score] increased after the intervention. Bacterial richness increased after 4 weeks of intervention and was negatively correlated with fasting glucose levels and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). Prevotella to Bacteroides ratio also increased after 4 weeks. In contrast, glycated haemoglobin (HbA1c) and HOMA-IR were only decreased at the end of study. Alkaline phosphatase activity was assessed in fecal samples and was negatively correlated with HbA1c and positively correlated with bacterial diversity. The results of this study reinforce that MD adherence results in a better glycemic control in subjects with T2D. Changes in gut bacterial richness caused by MD adherence may be relevant in mediating the metabolic impact of this dietary intervention.
Assuntos
Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/metabolismo , Dieta Mediterrânea , Microbioma Gastrointestinal , Idoso , Fosfatase Alcalina/metabolismo , Bacteroides/fisiologia , Biodiversidade , Pressão Sanguínea , Composição Corporal , Diabetes Mellitus Tipo 2/microbiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Fezes/microbiologia , Comportamento Alimentar , Feminino , Alimentos , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Projetos Piloto , Prevotella/fisiologia , Inquéritos e QuestionáriosRESUMO
We studied the effect of some mineral waters and some of their constituents on the apical uptake of (14)C-butyrate ((14)C-BT) and (3)H-O-methyl-D-glucose ((3)H-OMG) by Caco-2 cells. Uptake of (14)C-BT increased after a 20-minute exposure to 1 % (v/v) distilled water, and, compared to distilled water, it was decreased by Pedras Salgadas((R)) 1 % (v/v) and Melgaço((R)) 5 % (v/v), and increased by Vidago((R)) 5 % (v/v). Moreover, it increased after a 48-hour exposure to Vidago((R)) or Melgaço((R)) waters (5 % (v/v)). Also, uptake of (14)C-BT was reduced after a 20-minute exposure to MgCl(2), MgSO(4), or CaCl(2). Uptake of (3)H-OMG was reduced after a 20-minute exposure to Melgaço((R)) water [1 % (v/v)], when compared to distilled water. Also, a 48-hour exposure to Pedras Salgadas((R)) or Melgaço((R)) water (5 % (v/v)) increased and decreased uptake, respectively. Finally, uptake of (3)H-OMG decreased after a 20-minute exposure to MgSO(4) or NaF. In conclusion, uptake of (14)C-BT and (3)H-OMG by Caco-2 cells is differently modulated by distinct mineral waters.
Assuntos
3-O-Metilglucose/metabolismo , Butiratos/metabolismo , Águas Minerais , Células CACO-2 , Células Cultivadas , Humanos , Fatores de TempoRESUMO
Despite the recognized capacity of the gut microbiota to regulate intestinal lipid metabolism, the role of specific commensal species remains undefined. Here, we aimed to understand the bacterial effectors and molecular mechanisms by which Lactobacillus paracasei and Escherichia coli regulate lipid metabolism in enterocytes. We show that L-lactate produced by L. paracasei inhibits chylomicron secretion from enterocytes and promotes lipid storage by a mechanism involving L-lactate absorption by enterocytes, its conversion to malonyl-CoA, and the subsequent inhibition of lipid beta-oxidation. In contrast, acetate produced by E. coli also inhibits chylomicron secretion by enterocytes but promotes lipid oxidation by a mechanism involving acetate absorption by enterocytes, its metabolism to acetyl-CoA and AMP, and the subsequent upregulation of the AMPK/PGC-1α/PPARα pathway. Our study opens perspectives for developing specific bacteria- and metabolite-based therapeutic interventions against obesity, atherosclerosis, and malnutrition by targeting lipid metabolism in enterocytes.
Assuntos
Enterócitos/metabolismo , Escherichia coli/metabolismo , Fermentação , Lacticaseibacillus paracasei/metabolismo , Metabolismo dos Lipídeos , Simbiose , Animais , Linhagem Celular , Quilomícrons , Enterócitos/microbiologia , Feminino , Intestinos/microbiologia , Camundongos Endogâmicos C57BLRESUMO
BACKGROUND: Plant lectins have shown promising biological activities in the central nervous system (CNS). OBJECTIVE: This study evaluated the effect of DAL, a lectin isolated from the seeds of the Dioclea altissima species, having binding affinity to D-glucose or D-mannose residues, on mice behavior. METHODS: Mice (n=6/group) were treated (i.p.) with DAL (0.25, 0.5 or 1 mg/kg) or vehicle and subjected to several tests (open field/OFT, marble-burying/MBT, hole-board/HBT, elevated plus maze/PMT, tail suspension/ TST, forced swimming/FST or rotarod/RRT). Pizotifen, cyproheptadine, flumazenil, L-NAME, 7-NI, Larginine or yohimbine were administered 15 min before DAL (0.5 mg/kg) and the animals were evaluated on PMT. It was also verified whether the DAL effect depended on its structural integrity and ability to interact with carbohydrates. RESULTS: The results showed there were no neurobehavioral changes in the mice at the RRT, FST and locomotion in the OFT. DAL (0.25, 0.5 or 1 mg/kg) increased the behavior of grooming and rearing in the OFT, head dips in the HBT, pedalling in the TST and decreased the number of marbles hidden in the MBT. In the PMT, DAL (0.25, 0.5 and 1 mg/kg) and Diazepam increased the frequency of entries in the open arms and the time of permanence in the open arms without affecting the locomotor activity. The effect of DAL was dependent on carbohydrate interaction and protein structure integrity and it prevented by pizotifen, cyproheptadine, flumazenil, L-NAME and 7-NI, but not by L-arginine or yohimbine. CONCLUSION: DAL was found to have an anxiolytic-like effect mediated by the 5-HT and GABAergic receptors and NO pathway.
Assuntos
Ansiolíticos , Dioclea , Animais , Ansiolíticos/farmacologia , Antidepressivos , Comportamento Animal , Lectinas , Camundongos , Extratos Vegetais , SementesRESUMO
Folic acid (FA) is an essential micronutrient that is particularly important during pregnancy for normal placental and fetal development and growth. The placenta and the fetus become frequently exposed to drugs of abuse such as cannabinoids because of maternal use of these substances. The aim of this study was to investigate the influence of cannabinoids on the uptake of FA by BeWo cells. Acute treatment with anandamide (1-10 micromol/l) caused a 15% decrease in (3)H-FA uptake at pH 7.5. Moreover, tetrahydrocannabinol (THC) (1-10 micromol/l) caused a 30% increase, and AM630 (1 mumol/l) a 15% decrease in this parameter at pH 6.5. Neither the inhibitory effect of anandamide nor the stimulatory effect of THC were changed in the presence of cannabi- noid receptor type 1 or type 2 antagonists (AM251 and AM630, respectively). Chronic treatment (48 h) with THC (100 nmol/l) and AM251 (100 nmol/l) decreased the uptake of (3)H-FA by 20% at pH 7.5, and anandamide (1 micromol/l) and AM630 (10-500 nmol/l) increased it by 30%. Moreover, CP55,940 (10 nmol/l) increased the uptake of (3)H-FA by 30% at pH 6.5. RT-PCR analysis showed that the mRNA levels of the reduced folate transporter 1 increased by 9% after chronic treatment with AM630 (500 nmol/l). The mRNA levels of the proton-coupled folate transporter decreased by 17% and increased by 18% after chronic treatment with THC (0.1 mumol/l) and AM251 (100 nmol/l), respectively. In conclusion, (3)H-FA uptake by BeWo cells is significantly, although not very markedly, changed by several distinct CB receptor agonists and antagonists, both after acute and chronic exposure of the cells. The acute effects of cannabinoid receptor agonists do not seem to be mediated by the cannabinoid receptor, and with a few exceptions the chronic effects do not seem to be related to changes in the expression levels of FA transporters.