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1.
FASEB J ; 37(9): e23120, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37527279

RESUMO

The α7nAChR is crucial to the anti-inflammatory reflex, and to the expression of neuropeptides that control food intake, but its expression can be decreased by environmental factors. We aimed to investigate whether microRNA modulation could be an underlying mechanism in the α7nAchR downregulation in mouse hypothalamus following a short-term exposure to an obesogenic diet. Bioinformatic analysis revealed Let-7 microRNAs as candidates to regulate Chrna7, which was confirmed by the luciferase assay. Mice exposed to an obesogenic diet for 3 days had increased Let-7a and decreased α7nAChR levels, accompanied by hypothalamic fatty acids and TNFα content. Hypothalamic neuronal cells exposed to fatty acids presented higher Let-7a and TNFα levels and lower Chrna7 expression, but when the cells were pre-treated with TLR4 inhibitor, Let-7a, TNFα, and Chrna7 were rescued to normal levels. Thus, the fatty acids overload trigger TNFα-induced Let-7 overexpression in hypothalamic neuronal cells, which negatively regulates α7nAChR, an event that can be related to hyperphagia and obesity predisposition in mice.


Assuntos
Fator de Necrose Tumoral alfa , Receptor Nicotínico de Acetilcolina alfa7 , Animais , Camundongos , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ácidos Graxos , Regulação para Baixo , Hipotálamo/metabolismo
2.
Mol Biol Rep ; 49(4): 2655-2666, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35048271

RESUMO

INTRODUCTION: Metabolic alterations caused by an imbalance of macronutrient consumption are often related to the modulation of microRNAs (miRNAs), which could alter mRNAs expression profile and accelerate the development of non-alcoholic fatty liver disease (NAFLD). AIMS: This study aimed to investigate the contribution of miRNAs in modulating early stages of NAFLD in mice submitted to a high-fat diet (HFD). METHODS AND RESULTS: Male Swiss mice, fed either a control diet or an HFD for 1, 3, 7, 15, 30, 56 days, were assessed for metabolic alterations, gene expression and NAFLD markers. A hepatocyte cell line was used to investigate the effects of miR-370 modulation on enzymes involved in ß-oxidation. Body weight and adiposity were higher after 7 days of HFD. Fasting glucose and insulin increased after 3 and 7 days of HFD, respectively. While hepatic lipid content increased from the first day on, hepatic glycogen had a decrease after 3 days of HFD consumption. miR-370 and Let-7 expression increased with acute and chronic exposure to HFD, accompanied by carnitine palmitoyltransferase 1A (Cpt1a), acyl-CoA dehydrogenase very long chain (Acadvl) and protein kinase AMP-activated Catalytic Subunit 2 (Prkaa2) downregulation, while decreased miR-122 expression was accompanied by 1-acylglycerol-3-phosphate-O-acyltransferase (Agpat) upregulation after 56 days of HFD consumption, some of them confirmed by in vitro experiments. Despite fluctuations in TNFa and IL6 mRNA levels, molecular modulation was consistent with hepatic TG and NAFLD development. CONCLUSION: Hepatic miR-370-122-Let7 miRNA modulation could be the first insult to NAFLD development, preceding changes in glycemic homeostasis and adiposity.


Assuntos
MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo
3.
Br J Nutr ; 125(10): 1111-1124, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-32912341

RESUMO

We evaluated whether early-life protein restriction alters structural parameters that affect ß-cell mass on the 15th day and 20th day of gestation in control pregnant (CP), control non-pregnant (CNP), low-protein pregnant (LPP) and low-protein non-pregnant (LPNP) rats from the fetal to the adult life stage as well as in protein-restricted rats that recovered after weaning (recovered pregnant (RP) and recovered non-pregnant). On the 15th day of gestation, the CNP group had a higher proportion of smaller islets, whereas the CP group exhibited a higher proportion of islets larger than the median. The ß-cell mass was lower in the low-protein group than that in the recovered and control groups. Gestation increased the ß-cell mass, ß-cell proliferation frequency and neogenesis frequency independently of the nutritional status. The apoptosis frequency was increased in the recovered groups compared with that in the other groups. On the 20th day of gestation, a higher proportion of islets smaller than the median was observed in the non-pregnant groups, whereas a higher proportion of islets larger than the median was observed in the RP, LPP and CP groups. ß-Cell mass was lower in the low-protein group than that in the recovered and control groups, regardless of the physiological status. The ß-cell proliferation frequency was lower, whereas the apoptosis rate was higher in recovered rats compared with those in the low-protein and control rats. Thus, protein malnutrition early in life did not alter the mass of ß-cells, especially in the first two-thirds of gestation, despite the increase in apoptosis.


Assuntos
Apoptose , Proteínas Alimentares/administração & dosagem , Células Secretoras de Insulina/fisiologia , Desnutrição , Fenômenos Fisiológicos da Nutrição Pré-Natal , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Animais Recém-Nascidos , Dieta/veterinária , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Teste de Tolerância a Glucose , Insulina/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Gravidez , RNA/genética , RNA/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Aumento de Peso
4.
Int J Mol Sci ; 22(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069652

RESUMO

Obesity is a global health issue for which no major effective treatments have been well established. High-fat diet consumption is closely related to the development of obesity because it negatively modulates the hypothalamic control of food intake due to metaflammation and lipotoxicity. The use of animal models, such as rodents, in conjunction with in vitro models of hypothalamic cells, can enhance the understanding of hypothalamic functions related to the control of energy balance, thereby providing knowledge about the impact of diet on the hypothalamus, in addition to targets for the development of new drugs that can be used in humans to decrease body weight. Recently, sphingolipids were described as having a lipotoxic effect in peripheral tissues and the central nervous system. Specifically, lipid overload, mainly from long-chain saturated fatty acids, such as palmitate, leads to excessive ceramide levels that can be sensed by the hypothalamus, triggering the dysregulation of energy balance control. However, no systematic review has been undertaken regarding studies of sphingolipids, particularly ceramide and sphingosine-1-phosphate (S1P), the hypothalamus, and obesity. This review confirms that ceramides are associated with hypothalamic dysfunction in response to metaflammation, endoplasmic reticulum (ER) stress, and lipotoxicity, leading to insulin/leptin resistance. However, in contrast to ceramide, S1P appears to be a central satiety factor in the hypothalamus. Thus, our work describes current evidence related to sphingolipids and their role in hypothalamic energy balance control. Hypothetically, the manipulation of sphingolipid levels could be useful in enabling clinicians to treat obesity, particularly by decreasing ceramide levels and the inflammation/endoplasmic reticulum stress induced in response to overfeeding with saturated fatty acids.


Assuntos
Ceramidas/metabolismo , Metabolismo Energético/fisiologia , Ácidos Graxos/fisiologia , Animais , Ceramidas/fisiologia , Dieta Hiperlipídica/efeitos adversos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ácidos Graxos/metabolismo , Humanos , Hipotálamo/metabolismo , Hipotálamo/fisiologia , Resistência à Insulina/fisiologia , Leptina/metabolismo , Lisofosfolipídeos/metabolismo , Obesidade/metabolismo , Transdução de Sinais/fisiologia , Esfingolipídeos/metabolismo , Esfingosina/análogos & derivados , Esfingosina/metabolismo
5.
J Transl Med ; 18(1): 44, 2020 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-32000799

RESUMO

BACKGROUND: Crohn's disease (CD) is a multifactorial disease characterized by chronic intestinal inflammation. The increased visceral adiposity near the affected intestinal area, of which mesenteric adipose tissue (MAT) is the main component, is a feature of CD. Both protective and pathological roles have been attributed to this disease-associated tissue in CD. To understand the contribution of MAT to CD pathophysiology, a molecular and cellular signature of disease-associated MAT in CD patients was provided. METHODS: We performed an observational study with whole transcriptional analysis by RNA sequencing (RNA-seq) of MAT and ileal mucosa from CD patients with active disease and controls. qPCR and immunohistology were performed for validation analysis. RESULTS: RNA-seq identified 17 significantly regulated genes (|FC| > 1.5; FDR < 0.05) in CD-MAT compared to non-IBD controls, with a marked upregulation of plasma cell genes (i.e., IGLL5, MZB1, CD79A, POU2AF1, FCRL5, JCHAIN, DERL3, SDC1, PIM2). A less strict statistical cutoff value (|FC| > 1.5, nominal p ≤ 0.05) yielded a larger list of 651 genes in CD-MAT compared to controls. CD ileum showed the significant regulation compared to control ileum of 849 genes (|FC| > 1.5; FDR < 0.05) or 2654 genes (|FC| > 1.5, nominal p ≤ 0.05). Ingenuity Pathway Analysis revealed the significant regulation of pathways related to T- and B cell functionality in the MAT of CD patients. Despite the differences between the MAT and ileal signatures of CD patients, we identified a subset of 204 genes significantly modulated in both tissues compared to controls. This common signature included genes related to the plasma cell signature. Genes such as S100A8, S100A9 (calprotectin) and IL1B, which are associated with acute inflammatory response, were exclusively regulated in the ileal mucosa of CD disease. In contrast, some genes encoding for lymphocyte receptors such as MS4A1, CD3D and CD79A were exclusively regulated in CD-MAT, exhibiting a different pattern of immune cell activation compared to the ileal mucosa in CD patients. qPCR and immunohistology confirmed the presence of large infiltrates of CD3+ CD20+ lymphocytes and CD138+ plasma cells in CD-MAT. CONCLUSION: Our data strongly supports the role of CD-associated MAT as a site for T-, B- and plasma cell activation, and suggests that it could also act as a reservoir of memory immune responses.


Assuntos
Doença de Crohn , Tecido Adiposo , Linfócitos B , Doença de Crohn/genética , Humanos , Íleo , Mucosa Intestinal , Mesentério , Plasmócitos , Transdução de Sinais/genética , Linfócitos T
6.
Cell Physiol Biochem ; 53(4): 701-712, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31592599

RESUMO

BACKGROUND/AIMS: Cholinergic signalling mediated by the activation of muscarinic and nicotinic receptors has been described in the literature as a classic and important signalling pathway in the regulation of the inflammatory response. Recent research has investigated the role of acetylcholine, the physiological agonist of these receptors, in the control of energy homeostasis at the central level. Studies have shown that mice that do not express acetylcholine in brain regions regulating energy homeostasis present with excessive weight gain and hyperphagia. However, it has not yet been well-described in the literature which cholinergic receptor subunits are involved in this response; moreover, the signalling pathways responsible for the observed effects are not fully delineated. The hypothalamus is the regulating centre of energy homeostasis, and the α7 subunit of the nicotinic acetylcholine receptor (α7nAChR) is highly expressed in this region. When active, α7nAChR recruits proteins such as JAK2/STAT3 to mediate its signalling; the same intracellular components are required by leptin, an anorexigenic hormone. The aim of the present study was to evaluate the role of the hypothalamic α7nAChR in the control of energy homeostasis. METHODS: The work was performed on Swiss male mice. Initially, using immunofluorescent staining on brain sections, the presence of α7nAChR in hypothalamic cells regulating energy homeostasis was evaluated. Animals were submitted to stereotaxis in the lateral ventricle and intracerebroventricular stimulation (ICV) was used for the administration of an agonist (PNU) or antagonist (α-bungarotoxin) of α7nAChR. Metabolic parameters were evaluated and the expression of neuropeptides was evaluated in the hypothalamus by real-time PCR and western blot. The expression of hypothalamic neuropeptides was evaluated in mice treated with siRNA or inhibitors of JAK2/STAT3 (AG490 and STATTIC) proteins. We also evaluated food intake in α7nAChR knockout animals (α7KO). Additionally, in mouse hypothalamic cell culture (the mypHoA-POMC/GFP lineage), we evaluated the expression of neuropeptides and pSTAT3 after stimulation with PNU. RESULTS: Our results indicate co-localisation of α7nAChR with α-MSH, AgRP and NPY in hypothalamic cells. Pharmacological activation of α7nAChR reduced food intake and increased hypothalamic POMC expression and decreased NPY and AgRP mRNA levels and the protein content of pAMPK. Inhibition of α7nAChR with an antagonist increased the mRNA content of NPY and AgRP. Inhibition of α7nAChR with siRNA led to the suppression of POMC expression and an increase in AgRP mRNA levels. α7KO mice showed no changes in food intake. Inhibition of proteins involved in the JAK2/STAT3 signalling pathway reversed the effects observed after PNU stimulation. POMC-GFP cells, when treated with PNU, showed increased POMC expression and nuclear translocation of pSTAT3. CONCLUSION: Thus, selective activation of α7nAChR is able to modulate important markers of the response to food intake, suggesting that α7nAChR activation can suppress the expression of orexigenic markers and favour the expression of anorexics using the intracellular JAK2/STAT3 machinery.


Assuntos
Proteína Relacionada com Agouti/metabolismo , Janus Quinase 2/metabolismo , Pró-Opiomelanocortina/metabolismo , Fator de Transcrição STAT3/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Proteína Relacionada com Agouti/genética , Animais , Benzamidas/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Bungarotoxinas/farmacologia , Linhagem Celular , Ingestão de Alimentos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Pró-Opiomelanocortina/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/genética , Transdução de Sinais/efeitos dos fármacos , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Receptor Nicotínico de Acetilcolina alfa7/antagonistas & inibidores , Receptor Nicotínico de Acetilcolina alfa7/genética
7.
Am J Physiol Endocrinol Metab ; 312(4): E339-E347, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28196858

RESUMO

Over the past years, we have embarked in a systematic analysis of the effect of obesity or fatty acids on circulating monocytes, microvascular endothelial cells, macrophages, and skeletal muscle cells. With the use of cell culture strategies, we have deconstructed complex physiological systems and then reconstructed "partial equations" to better understand cell-to-cell communication. Through these approaches, we identified that in high saturated fat environments, cell-autonomous proinflammatory pathways are activated in monocytes and endothelial cells, promoting monocyte adhesion and transmigration. We think of this as a paradigm of the conditions promoting immune cell infiltration into tissues during obesity. In concert, it is possible that muscle and adipose tissue secrete immune cell chemoattractants, and indeed, our tissue culture reconstructions reveal that myotubes treated with the saturated fatty acid palmitate, but not the unsaturated fatty acid palmitoleate, release nucleotides that attract monocytes and other compounds that promote proinflammatory classically activated "(M1)-like" polarization in macrophages. In addition, palmitate directly triggers an M1-like macrophage phenotype, and secretions from these activated macrophages confer insulin resistance to target muscle cells. Together, these studies suggest that in pathophysiological conditions of excess fat, the muscle, endothelial and immune cells engage in a synergistic crosstalk that exacerbates tissue inflammation, leukocyte infiltration, polarization, and consequent insulin resistance.


Assuntos
Comunicação Celular/fisiologia , Inflamação/metabolismo , Resistência à Insulina/fisiologia , Músculo Esquelético/metabolismo , Obesidade/metabolismo , Animais , Células Cultivadas , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Músculo Esquelético/citologia
8.
Mediators Inflamm ; 2014: 736506, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25258479

RESUMO

We evaluated whether protein restriction in fetal life alters food intake and glucose homeostasis in adulthood by interfering with insulin signal transduction through proinflammatory mechanisms in the hypothalamus and peripheral tissues. Rats were divided into the following: a control group (C); a recovered group (R); and a low protein (LP) group. Relative food intake was greater and serum leptin was diminished in LP and R compared to C rats. Proinflammatory genes and POMC mRNA were upregulated in the hypothalamus of R group. Hypothalamic NPY mRNA expression was greater but AKT phosphorylation was diminished in the LP than in the C rats. In muscle, AKT phosphorylation was higher in restricted than in control animals. The HOMA-IR was decreased in R and C compared to the LP group. In contrast, the K(itt) in R was similar to that in C and both were lower than LP rats. Thus, nutritional recovery did not alter glucose homeostasis but produced middle hyperphagia, possibly due to increased anorexigenic neuropeptide expression that counteracted the hypothalamic inflammatory process. In long term protein deprived rats, hyperphagia most likely resulted from increased orexigenic neuropeptide expression, and glucose homeostasis was maintained, at least in part, at the expense of increased muscle insulin sensitivity.


Assuntos
Hipotálamo/imunologia , Hipotálamo/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Peso Corporal/fisiologia , Dieta com Restrição de Proteínas , Ingestão de Alimentos/fisiologia , Feminino , Immunoblotting , Masculino , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar
9.
Nutrients ; 16(3)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38337626

RESUMO

Maternal obesity and/or high-fat diet (HF) consumption can disrupt appetite regulation in their offspring, contributing to transgenerational obesity and metabolic diseases. As fatty acids (FAs) play a role in appetite regulation, we investigated the maternal and fetal levels of FAs as potential contributors to programmed hyperphagia observed in the offspring of obese dams. Female mice were fed either a control diet (CT) or HF prior to mating, and fetal and maternal blood and tissues were collected at 19 days of gestation. Elevated levels of linoleic acid were observed in the serum of HF dams as well as in the serum of their fetuses. An increased concentration of eicosadienoic acid was also detected in the hypothalamus of female HF-O fetuses. HF-O male fetuses showed increased hypothalamic neuropeptide Y (Npy) gene expression, while HF-O female fetuses showed decreased hypothalamic pro-opiomelanocortin (POMC) protein content. Both male and female fetuses exhibited reduced hypothalamic neurogenin 3 (NGN-3) gene expression. In vitro experiments confirmed that LA contributed to the decreased gene expression of Pomc and Ngn-3 in neuronal cells. During lactation, HF female offspring consumed more milk and had a higher body weight compared to CT. In summary, this study demonstrated that exposure to HF prior to and during gestation alters the FA composition in maternal serum and fetal serum and hypothalamus, particularly increasing n-6, which may play a role in the switch from POMC to NPY neurons, leading to increased weight gain in the offspring during lactation.


Assuntos
Neuropeptídeos , Obesidade Materna , Efeitos Tardios da Exposição Pré-Natal , Humanos , Feminino , Animais , Masculino , Gravidez , Camundongos , Dieta Hiperlipídica/efeitos adversos , Obesidade Materna/metabolismo , Ácidos Graxos/metabolismo , Pró-Opiomelanocortina/metabolismo , Obesidade/metabolismo , Aumento de Peso , Neuropeptídeos/metabolismo , Hipotálamo/metabolismo , Fenômenos Fisiológicos da Nutrição Materna , Efeitos Tardios da Exposição Pré-Natal/metabolismo
10.
Food Res Int ; 176: 113808, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38163714

RESUMO

Hypothalamic inflammation and metabolic changes resulting from the consumption of high-fat diets have been linked to low grade inflammation and obesity. Inflammation impairs the hypothalamic expression of α7 nicotinic acetylcholine receptor (α7nAChR). The α7nAChR is described as the main component of the anti-inflammatory cholinergic pathway in different inflammation models. To assess whether the reduction in α7nAChR expression exacerbates hypothalamic inflammation induced by a high-fat diet (HFD), were used male and female global α7nAChR knockout mouse line in normal or high-fat diet for 4 weeks. Body weight gain, adiposity, glucose homeostasis, hypothalamic inflammation, food intake, and energy expenditure were evaluated. Insulin sensitivity was evaluated in neuronal cell culture. Consumption of an HFD for 4 weeks resulted in body weight gain and adiposity in male Chrna7-/- mice and the hypothalamus of male Chrna7-/- mice showed neuroinflammatory markers, with increased gene expression of pro-inflammatory cytokines and dysregulation in the nuclear factor kappa B pathway. Moreover, male Chrna7-/- mice consuming an HFD showed alterations in glucose homeostasis and serum of Chrna7-/- mice that consumed an HFD impaired insulin signalling in neuronal cell culture experiments. In general, female Chrna7-/- mice that consumed an HFD did not show the phenotypic and molecular changes found in male mice, indicating that there is sexual dimorphism in the analysed parameters. Thus, receptor deletion resulted in increased susceptibility to hypothalamic inflammation and metabolic damage associated with HFD consumption in male mice.


Assuntos
Dieta Hiperlipídica , Receptor Nicotínico de Acetilcolina alfa7 , Masculino , Feminino , Animais , Camundongos , Dieta Hiperlipídica/efeitos adversos , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Camundongos Knockout , Obesidade/genética , Obesidade/metabolismo , Inflamação/metabolismo , Aumento de Peso , Hipotálamo/metabolismo , Fenótipo , Glucose/metabolismo
11.
Food Res Int ; 177: 113850, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38225125

RESUMO

Interesterified fats have been used to replace trans-fat in ultra-processed foods. However, their metabolic effects are not completely understood. Hence, this study aimed to investigate the effects related to glucose homeostasis in response to interesterified palm oil or refined palm oil intake. Four-week-old male Swiss mice were randomly divided into four experimental groups and fed the following diets for 8 weeks: a normocaloric and normolipidic diet containing refined palm oil (PO group) or interesterified palm oil (IPO group); a hypercaloric and high-fat diet containing refined PO (POHF group) or interesterified PO (IPOHF group). Metabolic parameters related to body mass, adiposity and food consumption showed no significant differences. As for glucose homeostasis parameters, interesterified palm oil diets (IPO and IPOHF) resulted in higher glucose intolerance than unmodified palm oil diets (PO and POHF). Euglycemic-hyperinsulinemic clamp assessment showed a higher endogenous glucose production in the IPO group compared with the PO group. Moreover, the IPO group showed significantly lower p-AKT protein content (in the muscle and liver tissues) when compared with the PO group. Analysis of glucose-stimulated static insulin secretion (11.1 mmol/L glucose) in isolated pancreatic islets showed a higher insulin secretion in animals fed interesterified fat diets (IPO and IPOHF) than in those fed with palm oil (PO and POHF). Interesterified palm oil, including in normolipidic diets, can impair insulin signaling in peripheral tissues and increase insulin secretion by ß-cells, characterizing insulin resistance in mice.


Assuntos
Resistência à Insulina , Masculino , Animais , Camundongos , Óleo de Palmeira , Óleos de Plantas , Gorduras na Dieta , Secreção de Insulina , Ácidos Graxos/análise , Dieta Hiperlipídica/efeitos adversos , Glucose
12.
J Biol Chem ; 287(19): 15580-9, 2012 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-22427667

RESUMO

Inflammation plays an important pathogenic role in a number of metabolic diseases such as obesity, type 2 diabetes, and atherosclerosis. The activation of inflammation in these diseases depends at least in part on the combined actions of TLR4 signaling and endoplasmic reticulum stress, which by acting in concert can boost the inflammatory response. Defining the mechanisms involved in this phenomenon may unveil potential targets for the treatment of metabolic/inflammatory diseases. Here we used LPS to induce endoplasmic reticulum stress in the human monocyte cell-line, THP-1. The unfolded protein response, produced after LPS, was dependent on CD14 activity but not on RNA-dependent protein kinase and could be inhibited by an exogenous chemical chaperone. The induction of the endoplasmic reticulum resident chaperones, GRP94 and GRP78, by LPS was of a much lower magnitude than the effect of LPS on TLR4 and MD-2 expression. In face of this apparent insufficiency of chaperone expression, we induced the expression of GRP94 and GRP78 by glucose deprivation. This approach completely reverted endoplasmic reticulum stress. The inhibition of either GRP94 or GRP78 with siRNA was sufficient to rescue the protective effect of glucose deprivation on LPS-induced endoplasmic reticulum stress. Thus, insufficient LPS-induced chaperone expression links TLR4 signaling to endoplasmic reticulum stress.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Chaperonas Moleculares/metabolismo , Transdução de Sinais/fisiologia , Receptor 4 Toll-Like/metabolismo , Animais , Linhagem Celular , Proteínas de Ligação a DNA/metabolismo , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Glucose/farmacologia , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Immunoblotting , Receptores de Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Antígeno 96 de Linfócito/metabolismo , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Chaperonas Moleculares/genética , Monócitos/citologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Fosforilação/efeitos dos fármacos , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Resposta a Proteínas não Dobradas/fisiologia , eIF-2 Quinase/deficiência , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
13.
Front Immunol ; 14: 1273556, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38193079

RESUMO

Introduction: High-fat diet (HFD) consumption is associated with various metabolic disorders and diseases. Both pre-pregnancy and maternal obesity can have long-term consequences on offspring health. Furthermore, consuming an HFD in adulthood significantly increases the risk of obesity and metabolic disorders. However, an intriguing phenomenon known as the obesity paradox suggests that obesity may confer a protective effect on mortality outcomes in sepsis. In sepsis, activation of the cholinergic anti-inflammatory pathway (CAP) can help mitigate systemic inflammation. We employed a metabolic programming model to explore the relationship between maternal HFD consumption and offspring response to sepsis. Methods: We fed female mice either a standard diet (SC) or an HFD during the pre-pregnancy, pregnancy, and lactation periods. Subsequently, we evaluated 28-day-old male offspring. Results: Notably, we discovered that offspring from HFD-fed dams (HFD-O) exhibited a higher survival rate compared with offspring from SC-fed dams (SC-O). Importantly, inhibition of the m1 muscarinic acetylcholine receptor (m1mAChR), involved in the CAP, in the hypothalamus abolished this protection. The expression of m1mAChR in the hypothalamus was higher in HFD-O at different ages, peaking on day 28. Treatment with an m1mAChR agonist could modulate the inflammatory response in peripheral tissues. Specifically, CAP activation was greater in the liver of HFD-O following agonist treatment. Interestingly, lipopolysaccharide (LPS) challenge failed to induce a more inflammatory state in HFD-O, in contrast to SC-O, and agonist treatment had no additional effect. Analysis of spleen immune cells revealed a distinct phenotype in HFD-O, characterized by elevated levels of CD4+ lymphocytes rather than CD8+ lymphocytes. Moreover, basal Il17 messenger RNA (mRNA) levels were lower while Il22 mRNA levels were higher in HFD-O, and we observed the same pattern after LPS challenge. Discussion: Further examination of myeloid cells isolated from bone marrow and allowed to differentiate showed that HFD-O macrophages displayed an anti-inflammatory phenotype. Additionally, treatment with the m1mAChR agonist contributed to reducing inflammatory marker levels in both groups. In summary, our findings demonstrate that HFD-O are protected against LPS-induced sepsis, and this protection is mediated by the central m1mAChR. Moreover, the inflammatory response in the liver, spleen, and bone marrow-differentiated macrophages is diminished. However, more extensive analysis is necessary to elucidate the specific mechanisms by which m1mAChR modulates the immune response during sepsis.


Assuntos
Doenças Metabólicas , Sepse , Humanos , Gravidez , Feminino , Masculino , Animais , Camundongos , Receptor Muscarínico M1 , Dieta Hiperlipídica/efeitos adversos , Lipopolissacarídeos , Acetilcolina , Obesidade/etiologia , RNA Mensageiro
16.
Cell Tissue Res ; 350(3): 549-52, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22948252

RESUMO

Crohn's disease (CD) is a chronic intestinal disease with a multifactorial etiology. Recently, a role for mesenteric fat has been proposed in CD pathophysiology, since fat hypertrophy is detected close to the affected intestinal area; however, there are few studies regarding autophagy and the hypertrophied mesenteric tissue in CD. To evaluate autophagy-related proteins in intestinal mucosae and mesenteric fat of patients with CD and controls, patients with ileocecal CD (CD Group) and with non-inflammatory disease (FC Group) selected for surgery were studied. Expression of LC3-II was determined by immunoblotting of protein extracts. In addition, beclin-1, LC3 and Atg16-L1 RNA levels were measured using RT-PCR. The expression of LC3-II was significantly lower in the mesenteric tissue and higher in intestinal mucosae of CD when compared to controls. However, mRNA expression of autophagy-related proteins was similar when comparing the mesenteric fat groups. These findings suggest a defect in autophagy activation in the mesenteric fat tissue of CD individuals, which could be involved in the maintenance of the inflammatory process.


Assuntos
Tecido Adiposo/patologia , Autofagia/fisiologia , Doença de Crohn/patologia , Mucosa Intestinal/patologia , Tecido Adiposo/metabolismo , Proteínas Reguladoras de Apoptose/biossíntese , Proteínas Reguladoras de Apoptose/genética , Proteínas Relacionadas à Autofagia , Proteína Beclina-1 , Biópsia , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Doença de Crohn/genética , Doença de Crohn/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Proteínas Associadas aos Microtúbulos/biossíntese , Proteínas Associadas aos Microtúbulos/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
17.
Front Cell Dev Biol ; 10: 830009, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35433669

RESUMO

Obesity has become a public health problem in recent decades, and during pregnancy, it can lead to an increased risk of gestational complications and permanent changes in the offspring resulting from a process known as metabolic programming. The offspring of obese dams are at increased risk of developing non-alcoholic fatty liver disease (NAFLD), even in the absence of high-fat diet consumption. NAFLD is a chronic fatty liver disease that can progress to extremely severe conditions that require surgical intervention with the removal of the injured tissue. Liver regeneration is necessary to preserve organ function. A range of pathways is activated in the liver regeneration process, including the Hippo, TGFß, and AMPK signaling pathways that are under epigenetic control. We investigated whether microRNA modulation in the liver of the offspring of obese dams would impact gene expression of Hippo, TGFß, and AMPK pathways and tissue regeneration after partial hepatectomy (PHx). Female Swiss mice fed a standard chow or a high-fat diet (HFD) before and during pregnancy and lactation were mated with male control mice. The offspring from control (CT-O) and obese (HF-O) dams weaned to standard chow diet until day 56 were submitted to PHx surgery. Prior to the surgery, HF-O presented alterations in miR-122, miR-370, and Let-7a expression in the liver compared to CT-O, as previously shown, as well as in its target genes involved in liver regeneration. However, after the PHx (4 h or 48 h post-surgery), differences in gene expression between CT-O and HF-O were suppressed, as well as in microRNA expression in the liver. Furthermore, both CT-O and HF-O presented a similar regenerative capacity of the liver within 48 h after PHx. Our results suggest that survival and regenerative mechanisms induced by the partial hepatectomy may overcome the epigenetic changes in the liver of offspring programmed by maternal obesity.

18.
J Nutr Biochem ; 104: 108977, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35248701

RESUMO

The aim of this study was to investigate certain parameters regarding the maternal-fetal outcomes in a diet-induced obesity model. Obese, glucose-intolerant females who were exposed to a high-fat diet prior to pregnancy had lower placental efficiency and lower birth weight pups compared to the controls. Simple linear regression analyses showed that maternal obesity disrupts the proportionality between maternal and fetal outcomes during pregnancy. Maternal obesity is correlated with fetal outcomes, perhaps because of problems with hormonal signaling and exacerbation of inflammation in the maternal metabolic environment. The maternal obese phenotype altered the thickness of the placental layer, the transport of fatty acids, and the expression of growth factors. For example, lower expression of epidermal growth factor receptor (EGFR) mRNA in the obesity-prone group may have contributed to the rupture of the placental layers, leading to adverse fetal outcomes. Furthermore, maintenance of maternal glucose homeostasis and overexpression of placental growth factor (PGF) in the obesity-resistant group likely protected the placenta and fetuses from morphological and functional damage.


Assuntos
Dieta Hiperlipídica , Obesidade Materna , Animais , Dieta Hiperlipídica/efeitos adversos , Feminino , Desenvolvimento Fetal , Retardo do Crescimento Fetal/genética , Glucose/metabolismo , Humanos , Camundongos , Obesidade/metabolismo , Fenótipo , Placenta/metabolismo , Fator de Crescimento Placentário/genética , Fator de Crescimento Placentário/metabolismo , Gravidez
19.
Cien Saude Colet ; 27(7): 2805-2816, 2022 Jul.
Artigo em Português, Inglês | MEDLINE | ID: mdl-35730848

RESUMO

This is a cross-sectional study evaluating the association between zinc deficiency and cognitive decline in 591 community-dwelling older adults living in the cities of Campinas, Limeira, and Piracicaba-SP. Cognitive status was evaluated using the Cognitive Abilities Screening Instrument-CASI-S, considering a decline for scores <23 for those aged 60-69 and <20 for those aged ≥70 years. Among the evaluated cognitive domains, older adults with zinc deficiency had significantly lower mean scores on the memory test (p=0.018). For zinc deficiency, values below 70 µg/dL were considered for women and 74 µg/dL for men. The prevalence of zinc deficiency was 3.9%, and cognitive deficit was 9.4%, being significantly higher in those with zinc deficiency compared with those with normal serum zinc concentrations. In adjusted multiple logistic regression analysis, the factors that remained associated with cognitive decline were zinc deficiency (OR=3.80; 95%CI=1.30-11.12), low schooling level (OR=3.12; 95%CI=1.49-6.50), lack of a partner (OR=1.88; 95%CI=1.04-3.42), risk of malnutrition (OR=3.98; 95%CI=2.36-6.71), and a history of encephalic vascular accident (OR=2.70; 95%CI=1.04-6.98). Zinc deficiency was associated with the presence of cognitive decline in older adults. Actions in primary health care are necessary to prevent the deficiency of this nutrient.


Estudo transversal avaliou a associação entre deficiência de zinco sérico e declínio cognitivo em 591 idosos da comunidade residentes nos municípios de Campinas, Limeira e Piracicaba-SP. A cognição foi avaliada pelo Instrumento de Triagem de Habilidades Cognitivas-CASI-S considerando declínio pontuação <23 em idosos de 60-69 anos e <20 em idosos ≥70 anos. Considerou-se deficiência de zinco sérico valor de <70 µg/dL para mulheres e 74 µg/dL para homens. Entre os domínios cognitivos, idosos com deficiência de zinco tiveram pontuação média significativamente menor no teste de memória (p=0,018). A prevalência da deficiência de zinco foi de 3,9%, e de 9,4% de declínio cognitivo, sendo significativamente maior em idosos com deficiência de zinco do que os que não tinham (26,1% e 8,8%, respectivamente). Em análise de regressão logística múltipla ajustada, os fatores que permaneceram associados ao declínio cognitivo foram deficiência de zinco (OR=3,80; IC95%=1,30-11,12), baixa escolaridade (OR=3,12; IC95%=1,49-6,50), não ter companheiro (OR=1,88; IC95%=1,04-3,42), risco de desnutrição (OR=3,98; IC95%=2,36-6,71), e histórico de acidente vascular encefálico (OR=2,70; IC95%=1,04-6,98). A deficiência de zinco foi associada ao declínio cognitivo em idosos. Ações na atenção básica de saúde são necessárias para prevenir a deficiência deste nutriente.


Assuntos
Disfunção Cognitiva , Desnutrição , Idoso , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etiologia , Estudos Transversais , Feminino , Humanos , Vida Independente , Masculino , Desnutrição/epidemiologia , Zinco
20.
World J Exp Med ; 12(1): 1-15, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35096550

RESUMO

The resolution of inflammation is an active process, guided by specialized pro-resolution lipid mediators (SPMs). These mediators originate from polyunsaturated fatty acids, such as omega-3. Sufficient evidence suggests that the beneficial effects attributed to omega-3 are, at least in part, the result of the immunomodulatory action of the SPMs, which act systemically by overcoming inflammation and repairing tissue damage, without suppressing the immune response. Recent studies suggest that an imbalance in the synthesis and/or activity of these compounds may be associated with the pathogenesis of several inflammatory conditions, such as inflammatory bowel disease (IBD). Thus, this review highlights the advances made in recent years with regard to the endo-genous synthesis and the biological role of lipoxins, resolvins, protectins, and maresins, as well as their precursors, in the regulation of inflammation; and provides an update on the participation of these mediators in the development and evolution of IBD and the therapeutic approaches that these immunomodulating substances are involved in this context.

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