RESUMO
SCOPE: Bovine milk extracellular vesicles (MEVs) have demonstrated therapeutic potential in regulating bone cell activity. However, the outcome of their use on alveolar bone loss has not yet been demonstrated. METHODS AND RESULTS: This study evaluates the effect of oral administration of MEVs on ovariectomized (OVX) mice. There is a reduced height of the alveolar bone crest in OVX mice by MEVs treatment, but the alveolar bone parameters are not altered. OVX mice are then submitted to a force-induced bone remodeling model by orthodontic tooth movement (OTM). MEVs-treated mice have markedly less bone remodeling movement, unlike the untreated OVX mice. Also, OVX mice treated with MEVs show an increased number of osteoblasts and osteocytes associated with higher sclerostin expression and reduce osteoclasts in the alveolar bone. Although the treatment with MEVs in OVX mice does not show differences in root structure in OTM, few odontoclasts are observed in the dental roots of OVX-treated mice. Compared to untreated mice, maxillary and systemic RANKL/OPG ratios are reduced in OVX mice treated with MEVs. CONCLUSION: Treatment with MEVs results in positive bone cell balance in the alveolar bone and dental roots, indicating its beneficial potential in treating alveolar bone loss in the nutritional context.
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Perda do Osso Alveolar , Camundongos , Animais , Feminino , Humanos , Perda do Osso Alveolar/prevenção & controle , Perda do Osso Alveolar/metabolismo , Leite , Osteoclastos/metabolismo , Osteoblastos/metabolismo , Remodelação Óssea/fisiologia , OvariectomiaRESUMO
Food intake patterns determine changes in energy expenditure due to their influence on body size and composition (percentage of fat, bone, and muscle), which can modulate signaling pathways that optimize energy consumption [...].
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Composição Corporal , Dieta , Composição Corporal/fisiologia , Comportamento Alimentar , Metabolismo Energético/fisiologia , Ingestão de EnergiaRESUMO
BACKGROUND: Obesity leads to chronic low-grade inflammation, promoting detrimental effects on bone. The consumption of virgin coconut oil (VCO) is associated with benefits related to meta-inflammation. We evaluated the effect of VCO supplementation on osteopenia promoted by diet-induced obesity in mice. METHODS: Male BALB/c mice were fed a control (C) or highly refined carbohydrate-containing (HC) diet for eight weeks. After that, the HC diet group was supplemented with three doses of VCO for four weeks. RESULTS: The HC diet increased the adiposity and leptin levels associated with augmented systemic inflammatory cells improved with VCO supplementation. The HC diet reduced the trabecular bone in the tibia, lumbar vertebrae, distal and proximal femur, as well as the bone mineral density of the femur and alveolar bone. The VCO supplementation reverted bone osteopenia by increasing the trabecular bone in different sites and improving femur and alveolar bone microarchitecture. Although the reduced number of osteoblasts in the alveolar bone of the HC diet group was not significantly enhanced by VCO supplementation, the reduced Alp expression in the HC diet group was enhanced in the VCO group. These beneficial effects were associated with lowering the Rankl/Opg ratio. CONCLUSION: VCO supplementation might be an effective strategy to attenuate bone osteopenic effects induced by obesity.
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BACKGROUND/OBJECTIVES: Platelet-activating factor receptor (PAFR) activation controls adipose tissue (AT) expansion in animal models. Our objective was twofold: (i) to check whether PAFR signaling is involved in human obesity and (ii) investigate the PAF pathway role in hematopoietic or non-hematopoietic cells to control adipocyte size. MATERIALS/SUBJECTS AND METHODS: Clinical parameters and adipose tissue gene expression were evaluated in subjects with obesity. Bone marrow (BM) transplantation from wild-type (WT) or PAFR-/- mice was performed to obtain chimeric PAFR-deficient mice predominantly in hematopoietic or non-hematopoietic-derived cells. A high carbohydrate diet (HC) was used to induce AT remodeling and evaluate in which cell compartment PAFR signaling modulates it. Also, 3T3-L1 cells were treated with PAF to evaluate fat accumulation and the expression of genes related to it. RESULTS: PAFR expression in omental AT from humans with obesity was negatively correlated to different corpulence parameters and more expressed in the stromal vascular fraction than adipocytes. Total PAFR-/- increased adiposity compared with WT independent of diet-induced obesity. Differently, WT mice receiving PAFR-/--BM exhibited similar adiposity gain as WT chimeras. PAFR-/- mice receiving WT-BM showed comparable augmentation in adiposity as total PAFR-/- mice, demonstrating that PAFR signaling modulates adipose tissue expansion through non-hematopoietic cells. Indeed, the PAF treatment in 3T3-L1 adipocytes reduced fat accumulation and expression of adipogenic genes. CONCLUSIONS: Therefore, decreased PAFR signaling may favor an AT accumulation in humans and animal models. Importantly, PAFR signaling, mainly in non-hematopoietic cells, especially in adipocytes, appears to play a significant role in regulating diet-induced AT expansion.
Assuntos
Tecido Adiposo/fisiopatologia , Obesidade/complicações , Glicoproteínas da Membrana de Plaquetas/farmacologia , Tecido Adiposo/metabolismo , Adulto , Animais , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Paris , Receptores Acoplados a Proteínas G , Transdução de Sinais/fisiologiaRESUMO
Studying effects of milk components on bone may have a clinical impact as milk is highly associated with bone maintenance, and clinical studies provided controversial associations with dairy consumption. We aimed to evaluate the impact of milk extracellular vesicles (mEVs) on the dynamics of bone loss in mice. MEVs are nanoparticles containing proteins, mRNA and microRNA, and were supplemented into the drinking water of mice, either receiving diet-induced obesity or ovariectomy (OVX). Mice receiving mEVs were protected from the bone loss caused by diet-induced obesity. In a more severe model of bone loss, OVX, higher osteoclast numbers in the femur were found, which were lowered by mEV treatment. Additionally, the osteoclastogenic potential of bone marrow-derived precursor cells was lowered in mEV-treated mice. The reduced stiffness in the femur of OVX mice was consequently reversed by mEV treatment, accompanied by improvement in the bone microarchitecture. In general, the RANKL/OPG ratio increased systemically and locally in both models and was rescued by mEV treatment. The number of osteocytes, as primary regulators of the RANKL/OPG system, raised in the femur of the OVX mEVs-treated group compared to OVX non-treated mice. Also, the osteocyte cell line treated with mEVs demonstrated a lowered RANKL/OPG ratio. Thus, mEVs showed systemic and local osteoprotective properties in two mouse models of bone loss reflected in reduced osteoclast presence. Data reveal mEV potential in bone modulation, acting via osteocyte enhancement and RANKL/OPG regulation. We suggest that mEVs could be a therapeutic candidate for the treatment of bone loss.
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Consumption of poor nutrients diets is associated with fat tissue expansion and with a central and peripheral low-grade inflammation. In this sense, the microglial cells in the central nervous system are activated and release pro-inflammatory cytokines that up-regulate the inducible nitric oxide synthase (iNOS), promoting Nitric Oxide (NO) production. The excess of NO has been proposed to facilitate anxious states in humans and rodents. We evaluated whether consumption of a high-refined carbohydrate-containing diet (HC) in mice induced anxiety-like behavior in the Novelty Suppressed Feeding Test (NFST) trough facilitation of NO, in the prefrontal cortex (PFC) and hippocampus (HIP). We also verified if HC diet induces activation of microglial cells, alterations in cytokine and leptin levels in such regions. Male BALB/c mice received a standard diet or a HC diet for 3 days or 12 weeks. The chronic consumption of HC diet, but not acute, induced an anxiogenic-like effect in the NSF test and an increase in the nitrite levels in the PFC and HIP. The preferential iNOS inhibitor, aminoguanidine (50 mg/kg, i.p.), attenuated such effects. Moreover, microglial cells in the HIP and PFC were activated after chronic consumption of HC diet. Finally, the expression of iNOS in the PFC and TNF, IL6 and leptin levels in HIP were higher in chronically HC fed mice. Taken together, our data reinforce the notion that diets containing high-refined carbohydrate facilitate anxiety-like behavior, mainly after a long period of consumption. The mechanisms involve, at least in part, the augmentation of neuroinflammatory processes in brain areas responsible for anxiety control.
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Ansiedade/metabolismo , Comportamento Animal , Carboidratos da Dieta/efeitos adversos , Inflamação/metabolismo , Tecido Adiposo/metabolismo , Animais , Ansiedade/induzido quimicamente , Modelos Animais de Doenças , Guanidinas/farmacologia , Hipocampo/metabolismo , Inflamação/induzido quimicamente , Leptina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase Tipo II/metabolismo , Nitritos/química , Córtex Pré-Frontal/metabolismoRESUMO
Obesity is characterized by adipose tissue expansion and chronic low-grade inflammation. Among the inflammatory mediators related to obesity development are the adipokines. These cytokines are released from fatty tissues and act in an autocrine, paracrine, or endocrine manner. Adipocytes influence the comorbidities of obesity such as osteoporosis (OP) and osteoarthritis (OA). It is still controversial as to whether OP is associated with either a low or high body mass index, but it is quite clear that the latter condition increases the risk for OA development. Bone marrow adipocytes (BMAs) have the same precursors of osteoblasts, which are the primary cells involved in bone formation, and the amount of BMAs appears to be inversely related to bone mineral density. Although adipokines released by these adipocytes influence bone loss progress, their exact role remains controversial. Differently, the infrapatellar fat pad (IPFP) is indicated to protect the function of joint regarding OA. However, there is relatively limited information about the secretion of adipokines and other inflammatory mediators by the IPFP. Despite some inconsistencies, nutritional interventions targeting obesity may also benefit patients with OP and OA. The association among obesity, OP, and OA is quite complex, and many factors need to be explored that are mainly related to the role of adipokines derived locally rather than from visceral and subcutaneous adipose tissue. Also, nutritional intervention may affect fatty tissue mass and secretion of inflammatory mediators that may, at least in part, influence other tissues in the organism such as bone and articular cartilage. The aim of this review was to present the latest knowledge about the interrelationship between obesity and OA or OP and to discuss whether a dietary intervention for obesity will hold promise for patients with OA or OP.
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Adipocinas/metabolismo , Mediadores da Inflamação/sangue , Obesidade/metabolismo , Osteoartrite/metabolismo , Osteoporose/metabolismo , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Índice de Massa Corporal , Osso e Ossos/metabolismo , Cartilagem Articular/metabolismo , Citocinas/metabolismo , Dietoterapia/métodos , Humanos , Articulação do Joelho/metabolismo , Obesidade/complicações , Obesidade/dietoterapia , Osteoartrite/dietoterapia , Osteoartrite/etiologia , Osteoporose/dietoterapia , Osteoporose/etiologiaRESUMO
Obesity is characterized by a chronic low-grade inflammation, which has been shown to be involved in the development of comorbidities such as insulin resistance, glucose intolerance, and liver damage. Phytochemicals found in plants may modulate inflammation and improve health problems associated with the excess of adiposity. Teas prepared with many plants are used in Brazil for losing weight. In this study, we evaluated the potential of Rudgea viburnoides (Cham.) Benth. on metabolic and inflammatory disarrangement induced by high refined carbohydrate (HC)-containing diet in mice. BALB/c mice were fed with chow or HC diet for 8 weeks. After this period, the HC diet was supplemented for 4 weeks with three different doses, 40, 80, and 160 mg/kg, of crude extract of R. viburnoides. Ethanol extract at the lowest dose (40 mg/kg) reduced adipocyte size, and improved glucose tolerance and insulin sensitivity. A lower concentration of proinflammatory mediators such as tumor necrosis factor-α, interleukin-6, and CCL2 in the liver and adipose tissue, and reduced levels of cholesterol and resistin in the serum were also observed. High concentrations of chlorogenic and caffeic acids, and the flavonoids, rutin and quercetin, were confirmed by high-performance liquid chromatography/diode array detector. Therefore, these data confirm the potential of R. viburnoides leaves as nutraceutical agents for the treatment of metabolic and inflammatory changes associated with obesity.
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Inflamação/prevenção & controle , Extratos Vegetais/farmacologia , Rubiaceae , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Carboidratos da Dieta , Suplementos Nutricionais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Obesidade Abdominal/prevenção & controle , Fitoterapia , Extratos Vegetais/uso terapêutico , Folhas de PlantaRESUMO
Obesity is characterized by abnormal adipose tissue expansion and is associated with chronic inflammation. Obesity itself may induce several comorbidities, including psychiatric disorders. It has been previously demonstrated that proinflammatory cytokines are able to up-regulate inducible nitric oxide synthase (iNOS) and nitric oxide (NO) release, which both have a role in compulsive related behaviors. OBJECTIVE: To evaluate whether acute or chronic consumption of a high-refined carbohydrate-containing (HC) diet will modify burying-behavior in the Marble Burying Test (MBT) through augmentation of NO signaling in the striatum, a brain region related to the reward system. Further, we also verified the effects of chronic consumption of a HC diet on the reinforcing effects induced by cocaine in the Conditioned Place Preference (CPP) test. METHODS: Male BALB/c mice received a standard diet (control diet) or a HC diet for 3 days or 12 weeks. RESULTS: An increase in burying behavior occurred in the MBT after chronic consumption of a HC diet that was associated with an increase of nitrite levels in the striatum. The pre-treatment with Aminoguanidine (50â¯mg/kg), a preferential inhibitor of iNOS, prevented such alterations. Additionally, a chronic HC diet also induced a higher expression of iNOS in this region and higher glutamate release from striatal synaptosomes. Neither statistical differences were observed in the expression levels of the neuronal isoform of NOS nor in microglia number and activation. Finally, the reinforcing effects induced by cocaine (15â¯mg/kg, i.p.) during the expression of the conditioned response in the CPP test were not different between the chronically HC diet fed mice and the control group. However, HC diet-feeding mice presented impairment of cocaine-preference extinction. CONCLUSION: Altogether, our results suggest that the chronic consumption of a HC diet induces compulsive-like behavior through a mechanism possibly associated with NO activation in the striatum.
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Comportamento Compulsivo/etiologia , Dieta da Carga de Carboidratos/efeitos adversos , Óxido Nítrico/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Cocaína/farmacologia , Condicionamento Psicológico/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Carboidratos da Dieta/efeitos adversos , Interleucina-6/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Potássio/metabolismoRESUMO
BACKGROUND: Annexin A1 (AnxA1) is a protein involved in inflammation resolution that might be altered in obesity-associated type 2 diabetes mellitus (DM), which is a chronic inflammatory disease. The aim of this study was to evaluate AnxA1 serum levels in individuals with and without DM stratified according to the body mass index (BMI), and the dynamic of AnxA1 expression in adipose tissue from humans with obesity and non-obesity. METHODS: Serum samples were obtained from 41 patients with DM (lean, overweight and obese) and 40 controls, and adipose tissue samples were obtained from 16 individuals with obesity (with or without DM), and 15 controls. RESULTS: DM patients showed similar AnxA1 serum levels when compared to controls. However, when the individuals were stratified according to BMI, AnxA1 levels were higher in individuals with obesity than lean or overweight, and in overweight compared to lean individuals. Moreover, AnxA1 was correlated positively with IL-6 levels. AnxA1 levels were also positively correlated with BMI, waist circumference and waist-to-hip ratio. Furthermore, higher levels of cleaved AnxA1 were observed in adipose tissue from individuals with obesity, independently of DM status. CONCLUSIONS: Enhanced levels of AnxA1 in serum of individuals with obesity suggest an attempt to counter-regulate the systemic inflammation process in this disease. However, the higher levels of cleaved AnxA1 in the adipose tissue of individuals with obesity could compromise its anti-inflammatory and proresolving actions, locally. Considering our data, AnxA1 cleavage in the adipose tissue, despite increased serum levels of this protein, and consequently the failure in inflammation resolution, suggests an important pathophysiological mechanism involved in inflammatory status observed in obesity.
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Tecido Adiposo/metabolismo , Anexina A1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Obesidade/metabolismo , Adulto , Idoso , Biomarcadores/metabolismo , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologiaRESUMO
The consumption of different types of diets influences not only body health but the bone remodeling process as well. Nutritional components can directly affect maxillary and mandibular alveolar bone microarchitecture. In this review, we focus on the current knowledge regarding the influence of diets and dietary supplementation on alveolar bone. Accumulating evidence from experimental models suggests that carbohydrate- and fat-rich diets are detrimental for alveolar bone, whereas protective effects are associated with consumption of calcium, ω-3, and bioactive compounds. Little is known about the effects of protein-free and protein-rich diets, boron, vitamin C, vitamin E, zinc, and caffeine on alveolar bone remodeling. Adipokines and direct effects of nutritional components on bone cells are proposed mechanisms linking diet and bone. Results from animal models substantiate the role of nutritional components on alveolar bone. It is a well-built starting point for clinical studies on nutritional monitoring and intervention for patients with alveolar bone disorders, especially those who are treatment refractory.
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Densidade Óssea , Dieta , Arcada Osseodentária/ultraestrutura , Adipocinas/sangue , Animais , Cálcio da Dieta/administração & dosagem , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Suplementos Nutricionais , Ácidos Graxos Ômega-3/administração & dosagem , Humanos , Micronutrientes/administração & dosagem , Modelos Animais , Avaliação NutricionalRESUMO
OBJECTIVES: Obesity is a chronic disease frequently associated with serious co-morbidities, such as diabetes type II, metabolic syndrome, and psychiatric disorders. Little is known, however, regarding the behavioral consequences of modified diet constituents and the propensity to development of stress related disorders. Thus, the aim of this study was to verify whether chronic exposure to a normocaloric/high-carbohydrate diet will modify the animal's behavior after different stressful stimuli. METHODS: BALB/c mice were fed for 12 weeks with a standard chow diet or high refined carbohydrate-containing diet (HC). Following this period, independent groups of animals were exposed to different stress paradigms: 1 - two hours of restraint stress followed by exposure to the Elevated Plus Maze test (EPM) 24 hours later; 2 - The contextual fear conditioning (CFC) test and 3 - the tail suspension test (TST). RESULTS: Despite no change on total body weight, animals fed with HC diet showed increase in serum leptin levels and higher adiposity compared to diet control group. In behavioral tests, animals from HC diet group displayed reduction in the percentage of entries into the open arms of the EPM, evaluated 24 hours after restraint stress, suggesting an anxiogenic-like effect. It is also observed increase in aversive memory in the CFC test and depressive-like behavior in TST. DISCUSSION: Our results suggest that a moderate obesity, induced by high refined carbohydrate diet, may facilitate the development of anxiety and depressive-like behaviors after the stress. The mechanisms responsible for such effects remain to be elucidated.
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Ansiedade/diagnóstico , Depressão/diagnóstico , Dieta da Carga de Carboidratos/efeitos adversos , Carboidratos da Dieta/efeitos adversos , Estresse Psicológico , Animais , Ansiedade/etiologia , Comportamento Animal/efeitos dos fármacos , Peso Corporal , Depressão/etiologia , Dieta , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB CRESUMO
The claimed beneficial effect of milk on bone is still a matter for debate. Recently extracellular vesicles (EVs) that contain proteins and RNA were discovered in milk, but their effect on bone formation has not yet been determined. We demonstrated previously that bovine milk-derived EVs (BMEVs) have immunoregulatory properties. Our aim was to evaluate the effect of BMEVs on osteogenesis by mice and human mesenchymal stem cells (hMSCs). Oral delivery of two concentrations of BMEVs to female DBA/1J mice during 7weeks did not alter the tibia trabecular bone area; however, the osteocytes number increased. In addition, the highest dose of BMEVs markedly increased the woven bone tissue, which is more brittle. The exposure of hMSCs to BMEVs during 21days resulted in less mineralization but higher cell proliferation. Interestingly BMEVs reduced the collagen production, but enhanced the expression of genes characteristic for immature osteoblasts. A kinetic study showed that BMEVs up-regulated many osteogenic genes within the first 4days. However, the production of type I collagen and expression of its genes (COL1A1 and COL1A2) were markedly reduced at days 21 and 28. At day 28, BMEVs again lead to higher proliferation, but mineralization was significantly increased. This was associated with increased expression of sclerostin, a marker for osteocytes, and reduced osteonectin, which is associated to bone matrix formation. Our study adds BMEVs to the list of milk components that can affect bone formation and may shed new light on the contradictory claims of milk on bone formation.
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Matriz Óssea/metabolismo , Osteoblastos/citologia , Animais , Diferenciação Celular , Feminino , Camundongos , Camundongos Endogâmicos DBARESUMO
Metabolic alterations are associated with arthritis apart from obesity. However, it is still unclear which is the underlying process behind these metabolic changes. Here, we investigate the role of tumor necrosis factor (TNF) in this process in an acute model of antigen-induced arthritis (AIA). Immunized male BALB/c mice received an intra-articular injection of PBS (control) or methylated bovine serum albumin (mBSA) into their knees, and were also pre-treated with different drugs: Etanercept, an anti-TNF drug, DF2156A, a CXCR1/2 receptor antagonist, or a monoclonal antibody RB6-8C5 to deplete neutrophils. Local challenge with mBSA evoked an acute neutrophil influx into the knee joint, and enhanced the joint nociception, along with a transient systemic metabolic alteration (higher levels of glucose and lipids, and altered adipocytokines). Pre-treatment with the conventional biological Etanercept, an inhibitor of TNF action, ameliorated the nociception and the acute joint inflammation dominated by neutrophils, and markedly improved many of the altered systemic metabolites (glucose and lipids), adipocytokines and PTX3. However, the lessening of metabolic changes was not due to diminished accumulation of neutrophils in the joint by Etanercept. Reduction of neutrophil recruitment by pre-treating AIA mice with DF2156A, or even the depletion of these cells by using RB6-8C5 reduced all of the inflammatory parameters and hypernociception developed after AIA challenge, but could not prevent the metabolic changes. Therefore, the induction of joint inflammation provoked acute metabolic alterations which were involved with TNF. We suggest that the role of TNF in arthritis-associated metabolic changes is not due to local neutrophils, which are the major cells present in this model, but rather due to cytokines.
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Anti-Inflamatórios não Esteroides/farmacologia , Artrite Experimental/tratamento farmacológico , Cartilagem Articular/efeitos dos fármacos , Etanercepte/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adipocinas/genética , Adipocinas/metabolismo , Animais , Anticorpos Monoclonais/farmacologia , Artrite Experimental/induzido quimicamente , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Proteína C-Reativa/genética , Proteína C-Reativa/metabolismo , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Bovinos , Expressão Gênica , Glucose/metabolismo , Injeções Intra-Articulares , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Neutrófilos/patologia , Receptores de Interleucina-8A/antagonistas & inibidores , Receptores de Interleucina-8A/genética , Receptores de Interleucina-8A/metabolismo , Receptores de Interleucina-8B/antagonistas & inibidores , Receptores de Interleucina-8B/genética , Receptores de Interleucina-8B/metabolismo , Soroalbumina Bovina , Sulfonamidas/farmacologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
OBJECTIVE: The role of platelet-activating factor (PAF) on diet-induced inflammatory and metabolic dysfunction is unknown. The effects of diet-induced metabolic and inflammatory dysfunction in mice with deletion of the PAF receptor (PAFR(-/-) ) were evaluated in this study. METHODS: Wild-type and PAFR(-/-) mice were fed chow (WT-C and PAFR(-/-) -C) or high-refined carbohydrate-containing diet (WT-HC and PAFR(-/-) -HC). PAFR(-/-) - RESULTS: HC mice gained more weight and adiposity than PAFR(-/-) -C and WT-HC mice. Lipogenesis increased and hormone-sensitive lipase expression decreased in PAFR(-/-) -HC compared to WT-HC mice. WT-HC mice had impaired glucose tolerance and insulin sensitivity compared to WT-C mice. In contrast, glucose tolerance and insulin sensitivity in PAFR(-/-) -HC mice were similar to that of lean littermates. PAFR(-/-) -HC mice expressed significantly more peroxisome proliferator-activator receptor gamma (PPARγ) than PAFR(-/-) -C and WT-C mice. Resistin increased in WT-HC mice compared to WT-C mice. However, the levels of resistin were 35% lower in PAFR(-/-) -HC mice than WT-HC mice. PAFR(-/-) presented with less HC diet-induced adipose tissue inflammation than WT mice. Adipocytes isolated from PAFR(-/-) mice incubated in media containing normal or high levels of glucose secreted less interleukin-6 and tumor necrosis factor alpha and presented lower rate of lipolysis than WT mice. CONCLUSION: PAFR deficiency resulted in less inflammation in adipose tissue and improvement in glucose homeostasis when fed the HC diet. The higher adiposity observed in PAFR(-/-) mice fed HC diet could be owing to the maintenance of insulin sensitivity, decreased adipocyte lipolysis rate, high lipogenesis and PPARγ expression, and lower inflammatory milieu in adipose tissue.
Assuntos
Dieta , Carboidratos da Dieta/efeitos adversos , Inflamação/metabolismo , Glicoproteínas da Membrana de Plaquetas/deficiência , Glicoproteínas da Membrana de Plaquetas/metabolismo , Receptores Acoplados a Proteínas G/deficiência , Receptores Acoplados a Proteínas G/metabolismo , Adipócitos/metabolismo , Tecido Adiposo , Adiposidade/fisiologia , Animais , Carboidratos da Dieta/administração & dosagem , Intolerância à Glucose , Resistência à Insulina , Interleucina-6/metabolismo , Lipogênese , Lipólise/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , PPAR gama/genética , PPAR gama/metabolismo , Glicoproteínas da Membrana de Plaquetas/genética , Receptores Acoplados a Proteínas G/genética , Resistina/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Aumento de PesoRESUMO
OBJECTIVE: The effects of high-refined carbohydrate-containing diet (HC) on inflammatory parameters and metabolic disarrangement of adipose tissue are poorly understood. The aim of this study was to evaluate the timing and progression of metabolic and inflammatory dysfunction induced by HC diet in mice. DESIGN AND METHODS: BALB/c mice were fed chow or HC diet for 1 and 3 days, 1, 2, 4, 6, 8, 10, and 12 weeks. RESULTS: Animals given HC diet exhibited acute and sustained increase in visceral adiposity, glucose intolerance, low insulin sensitivity, hyperlipemia, acute increase in mRNA expression of ACC, LPL, PPARγ, SREBP-1, and ChREBP and altered circulating levels of adiponectin, resistin, and leptin. There was leucocyte rolling and adhesion on adipose tissue microvessels already at 3 days and until 8 weeks of HC diet. Adipose tissue of mice had increased number of macrophages (M1 and M2), lymphocytes (CD8+ and CD4+ Foxp3+), and neutrophils (GR1+) already at 3 days after initiation of HC diet. Overall, concentration of cytokines and chemokines, TNF-α, IL-6, IL-10, TGF-ß1, CCL2, and CXCL1, in adipose tissue was elevated throughout the experimental period. Levels of IL-10 and TGF-ß1 tended to reach baseline levels at 12 weeks of HC diet. CONCLUSIONS: We describe a novel murine model of fat pad expansion induced by HC diet that is characterized by early onset and sustained adipose tissue inflammation and metabolic disarrangement. The acute inflammatory response in adipose tissue occurs very early and is sustained, suggesting that adipose tissue inflammation is a homeostatic mechanism to regulate nutrient overload and adipose expansion.
Assuntos
Tecido Adiposo , Dieta/efeitos adversos , Carboidratos da Dieta/efeitos adversos , Mediadores da Inflamação/metabolismo , Inflamação/etiologia , Doenças Metabólicas/etiologia , Obesidade Abdominal/complicações , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Adipocinas/sangue , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Modelos Animais de Doenças , Intolerância à Glucose/etiologia , Intolerância à Glucose/metabolismo , Hiperlipidemias/etiologia , Hiperlipidemias/metabolismo , Inflamação/metabolismo , Resistência à Insulina , Leucócitos/metabolismo , Lipase Lipoproteica/genética , Lipase Lipoproteica/metabolismo , Masculino , Doenças Metabólicas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Microvasos , Obesidade Abdominal/induzido quimicamente , Obesidade Abdominal/metabolismo , Obesidade Abdominal/patologia , PPAR gama/genética , PPAR gama/metabolismo , RNA Mensageiro/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismoRESUMO
Os autores descrevem e analisam 33 casos de violência ou negligência praticados contra menores, que foram atendidos em caráter de urgência no Hospital Universitário da USP, no bienio 92-93. A abordagem dos casos foi feita sistematicamente por equipe constituida por pediatra, assistente social e psiquiatra...