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White adipose tissue (WAT) controls energy storage, expenditure, and endocrine function. Rho-kinase (ROCK) is related to impaired thermogenesis, downregulation of preadipocyte differentiation, and adipokine production. Furthermore, WAT ROCK responds to metabolic stress from high-fat diets or diabetes. However, ROCK distribution in adipose depots and its response to aging and sex remain unclear. Thus, we aim to investigate ROCK function in adipose tissue of rodent and human in response to aging and sex. We observed specific differences in the ROCK1/2 distribution in inguinal WAT (ingWAT), perigonadal WAT (pgWAT), and brown adipose tissue of male and female rodents. However, ROCK2 expression was lower in female ingWAT compared with males, a fact that was not observed in the other depots. In the pgWAT and ingWAT of male and female rodents, ROCK activity increased during development. Moreover, middle-aged female rodents and humans showed downregulation in ROCK activity after acute physical exercise. Interestingly, ROCK levels were associated with several inflammatory markers both in rats and humans WAT (Nfkb1, Tnf, Il1b, Il6, and Mcp1). Induction of cell senescence by etoposide elevates ROCK activity in human preadipocytes; however, silencing ROCK1/2 demonstrates improvement in the inflammatory and cell senescence state. Using public databases, several pathways were strongly associated with ROCK modulation in WAT. In summary, WAT ROCK increases with development in association with inflammatory markers. Further, ROCK activity was attenuated by acute physical exercise, implicating it as a possible therapeutic target for metabolism improvement mediated by adipose tissue inflammatory state changes.
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Roedores , Quinases Associadas a rho , Humanos , Ratos , Masculino , Feminino , Animais , Pessoa de Meia-Idade , Quinases Associadas a rho/fisiologia , Obesidade/metabolismo , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Envelhecimento , Tecido AdiposoRESUMO
OBJECTIVE: The mitochondrial unfolded protein response (UPRmt) is an adaptive cellular response to stress to ensure mitochondrial proteostasis and function. Here we explore the capacity of physical exercise to induce UPRmt in the skeletal muscle. METHODS: Therefore, we combined mouse models of exercise (swimming and treadmill running), pharmacological intervention, and bioinformatics analyses. RESULTS: Firstly, RNA sequencing and Western blotting analysis revealed that an acute aerobic session stimulated several mitostress-related genes and protein content in muscle, including the UPRmt markers. Conversely, using a large panel of isogenic strains of BXD mice, we identified that BXD73a and 73b strains displayed low levels of several UPRmt-related genes in the skeletal muscle, and this genotypic feature was accompanied by body weight gain, lower locomotor activity, and aerobic capacity. Finally, we identified that c-Jun N-terminal kinase (JNK) activation was critical in exercise-induced UPRmt in the skeletal muscle since pharmacological JNK pathway inhibition blunted exercise-induced UPRmt markers in mice muscle. CONCLUSION: Our findings provide new insights into how exercise triggers mitostress signals toward the oxidative capacity in the skeletal muscle.
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Proteínas Quinases JNK Ativadas por Mitógeno , Condicionamento Físico Animal , Animais , Camundongos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Mitocôndrias/metabolismo , Músculo Esquelético/metabolismo , Resposta a Proteínas não Dobradas , Proteína Quinase 8 Ativada por Mitógeno/metabolismoRESUMO
Obesity can exacerbate the systemic inflammatory process, leading to increased infiltration of monocytes in white adipose tissue (WAT) and polarization of these cells into pro-inflammatory M1 macrophages, while reducing the population of anti-inflammatory M2 macrophages. Aerobic exercise has been shown to be effective in reducing the pro-inflammatory profile. However, the impact of strength training and the duration of training on macrophage polarization in the WAT of obese individuals have not been widely studied. Therefore, our aim was to investigate the effects of resistance exercise on macrophage infiltration and polarization in the epididymal and subcutaneous adipose tissue of obese mice. We compared the following groups: Control (CT), Obese (OB), Obese 7-day strength training (STO7d), and Obese 15-day strength training (STO15d). Macrophage populations were evaluated by flow cytometry: total macrophages (F4/80+), M1 (CD11c), and M2 (CD206) macrophages. Our results demonstrated that both training protocols improved peripheral insulin sensitivity by increasing AKT phosphorylation (Ser473). Specifically, the 7-day training regimen reduced total macrophage infiltration and M2 macrophage levels without altering M1 levels. In the STO15d group, significant differences were observed in total macrophage levels, M1 macrophages, and the M1/M2 ratio compared to the OB group. In the epididymal tissue, a reduction in the M1/M2 ratio was observed in the STO7d group. Overall, our data demonstrate that 15 days of strength exercise can reduce the M1/M2 ratio of macrophages in white adipose tissue.
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Tecido Adiposo , Resistência à Insulina , Camundongos , Animais , Inflamação , Tecido Adiposo Branco , Obesidade/terapia , Macrófagos , Camundongos Endogâmicos C57BL , Camundongos ObesosRESUMO
The gut has been suggested as the first organ to be affected by unbalanced diets contributing to the obesogenic process. This study aimed to test a short time-course exposition model to a known pro- or anti-inflammatory enriched fatty diet to understand the early gut alterations. Male mice were exposed to the chow diet (CT), high-fat (HF) diet, or a high-fat diet partially replaced on flaxseed oil (FS), rich in omega-3 (ω3), for 14 days. HF and FS increased the total body weight mass compared with the CT group, but FS reduced the epididymal fat depot compared to HF. The bioinformatics from mice and human databases showed the Zo1-Ocln-Cldn7 tight junctions as the main protein-triad. In the ileum, the HF diet has increased IL1ß transcript and IL1ß, TNFα, and CD11b proteins, but reduced the tight junctions (Zo1, Ocln, and Cld7) compared to the CT group. Despite the FS diet being partially efficient in protecting the ileum against inflammation, the tight junctions were increased, compared to the HF group. The GPR120 and GPR40 receptors were unaffected by diets, but GPR120 was colocalized on the surface of ileum macrophages. The short period of a high-fat diet was enough to start the obesogenic process, ileum inflammation, and reduce the tight junctions. Flaxseed oil did not protect efficiently against dysmetabolism. Still, it increased the tight junctions, even without alteration on inflammatory parameters, suggesting the protection against gut permeability during early obesity development.
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Ácidos Graxos Ômega-3 , Óleo de Semente do Linho , Humanos , Masculino , Animais , Camundongos , Óleo de Semente do Linho/farmacologia , Junções Íntimas/metabolismo , Ácidos Graxos Insaturados , Inflamação/metabolismo , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL , Ácidos GraxosRESUMO
Physical training is a potent therapeutic approach for improving mitochondrial health through peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) signaling pathways. However, comprehensive information regarding the physical training impact on PGC-1α in the different physiological systems with advancing age is not fully understood. This review sheds light on the frontier-of-knowledge data regarding the chronic effects of exercise on the PGC-1α signaling pathways in rodents and humans. We address the molecular mechanisms involved in the different tissues, clarifying the precise biological action of PGC-1α, restricted to the aged cell type. Distinct exercise protocols (short and long-term) and modalities (aerobic and resistance exercise) increase the transcriptional and translational PGC-1α levels in adipose tissue, brain, heart, liver, and skeletal muscle in animal models, suggesting that this versatile molecule induces pleiotropic responses. However, PGC-1α function in some human tissues (adipose tissue, heart, and brain) remains challenging for further investigations. PGC-1α is not a simple transcriptional coactivator but supports a biochemical environment of mitochondrial dynamics, controlling physiological processes (primary metabolism, tissue remodeling, autophagy, inflammation, and redox balance). Acting as an adaptive mechanism, the long-term effects of PGC-1α following exercise may reflect the energy demand to coordinate multiple organs and contribute to cellular longevity.
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Condicionamento Físico Animal , Fenômenos Fisiológicos , Animais , Humanos , Idoso , Exercício Físico , Fatores de Transcrição/metabolismo , Músculo Esquelético/fisiologia , Envelhecimento/fisiologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Condicionamento Físico Animal/fisiologiaRESUMO
OBJECTIVE: Intriguingly, hyperinsulinemia, and hyperglycemia can predispose insulin resistance, obesity, and type 2 diabetes, leading to metabolic disturbances. Conversely, physical exercise stimulates skeletal muscle glucose uptake, improving whole-body glucose homeostasis. Therefore, we investigated the impact of short-term physical activity in a mouse model (Slc2a4+/-) that spontaneously develops hyperinsulinemia and hyperglycemia even when fed on a chow diet. METHODS: Slc2a4+/- mice were used, that performed 5 days of endurance or strength exercise training. Further analysis included physiological tests (GTT and ITT), skeletal muscle glucose uptake, skeletal muscle RNA-sequencing, mitochondrial function, and experiments with C2C12 cell line. RESULTS: When Slc2a4+/- mice were submitted to the endurance or strength training protocol, improvements were observed in the skeletal muscle glucose uptake and glucose metabolism, associated with broad transcriptomic modulation, that was, in part, related to mitochondrial adaptations. The endurance training, but not the strength protocol, was effective in improving skeletal muscle mitochondrial activity and unfolded protein response markers (UPRmt). Moreover, experiments with C2C12 cells indicated that insulin or glucose levels could contribute to these mitochondrial adaptations in skeletal muscle. CONCLUSIONS: Both short-term exercise protocols were efficient in whole-body glucose homeostasis and insulin resistance. While endurance exercise plays an important role in transcriptome and mitochondrial activity, strength exercise mostly affects post-translational mechanisms and protein synthesis in skeletal muscle. Thus, the performance of both types of physical exercise proved to be a very effective way to mitigate the impacts of hyperglycemia and hyperinsulinemia in the Slc2a4+/- mouse model.
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Diabetes Mellitus Tipo 2 , Hiperglicemia , Resistência à Insulina , Camundongos , Animais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Músculo Esquelético/metabolismo , Hiperglicemia/genética , Hiperglicemia/metabolismo , Glucose/metabolismo , Transportador de Glucose Tipo 4/metabolismoRESUMO
It is known that long-term high-fat diet (HF) feeding drastically affects the adipose tissue, contributing to metabolic disorders. Recently, short-term HF consumption was shown to affect different neuronal signaling pathways. Thus, we aimed to evaluate the inflammatory effects of a short-term HF and whether a diet containing omega-3 fatty acid fats from flaxseed oil (FS) has protective effects. Mice were divided into three groups for 3 d, according to their diets: Control group (CT), HF, or FS for 3 d. Lipid profiles were assessed through mass spectrometry and inflammatory markers by RT-qPCR and Western blotting. After short-term HF, mice increased food intake, body weight, adiposity, and fasting glucose. Increased mRNA content of Ccl2 and Tnf was demonstrated in the HF compared to CT in mesenteric adipose tissue. In the liver, TNFα protein was higher in the HF group than in CT, followed by a decreased polyunsaturated fatty acids tissue incorporation in HF. On the other hand, the consumption of FS reduced food intake and fasting glucose, as well as increased omega-3 fatty acid incorporation in MAT and the liver. However, short-term FS was insufficient to control the early inflammation triggered by HF in MAT and the liver. These data demonstrated that a 3-d HF diet is enough to damage glucose homeostasis and trigger inflammation. In contrast, short-term FS protects against increased food intake and fasting glucose but not inflammation in mice.
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Dieta Hiperlipídica , Ácidos Graxos Ômega-3 , Camundongos , Animais , Dieta Hiperlipídica/efeitos adversos , Óleo de Semente do Linho/farmacologia , Ácidos Graxos Ômega-3/farmacologia , Ácidos Graxos Ômega-3/metabolismo , Inflamação/metabolismo , Tecido Adiposo/metabolismo , Glucose/metabolismo , Camundongos Endogâmicos C57BLRESUMO
Background: Acute exercise contributes to decreased feeding through leptin and interleukin/Janus kinase 2/signal transducers and activators of transcription 3 (IL-6/JAK2/STAT3) signaling. Considering the pleiotropic use of substrates by JAK2 and that JAK2 can phosphorylate the Tubby protein (TUB) in CHO-IR cells, we speculated that acute exercise can activate the IL-6/JAK2/TUB pathway to decrease food intake. Aims: We investigated whether acute exercise induced tyrosine phosphorylation and the association of TUB and JAK2 in the hypothalamus and if IL-6 is involved in this response, whether acute exercise increases the IL-6/TUB axis to regulate feeding, and if leptin has an additive effect over this mechanism. Methods: We applied a combination of genetic, pharmacological, and molecular approaches. Key findings: The in vivo experiments showed that acute exercise increased the tyrosine phosphorylation and association of JAK2/TUB in the hypothalamus, which reduced feeding. This response was dependent on IL-6. Leptin had no additive effect on this mechanism. Significance: The results of this study suggest a novel hypothalamic pathway by which IL-6 released by exercise regulates feeding and reinforces the beneficial effects of exercise.
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Omega 3 (ω3) fatty acids have been described since the 1980s as promising anti-inflammatory substances. Prostaglandin and leukotriene modulation were exhaustively explored as the main reason for ω3 beneficial outcomes. However, during the early 2000s, after the human genome decoding advent, the nutrigenomic approaches exhibited an impressive plethora of ω3 targets, now under the molecular point of view. Different G protein-coupled receptors (GPCRs) recognizing ω3 and its derivatives appear to be responsible for blocking inflammation and insulin-sensitizing effects. A new class of ω3-derived substances, such as maresins, resolvins, and protectins, increases ω3 actions. Inflammasome disruption, the presence of GPR120 on immune cell surfaces, and intracellular crosstalk signaling mediated by PPARγ compose the last discoveries regarding the multipoint anti-inflammatory targets for this nutrient. This review shows a detailed mechanistic proposal to understand ω3 fatty acid action over the inflammatory environment in the background of several chronic diseases.
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Hypothalamic interleukin-6 (IL6) exerts a broad metabolic control. Here, we demonstrated that IL6 activates the ERK1/2 pathway in the ventromedial hypothalamus (VMH), stimulating AMPK/ACC signaling and fatty acid oxidation in mouse skeletal muscle. Bioinformatics analysis revealed that the hypothalamic IL6/ERK1/2 axis is closely associated with fatty acid oxidation- and mitochondrial-related genes in the skeletal muscle of isogenic BXD mouse strains and humans. We showed that the hypothalamic IL6/ERK1/2 pathway requires the α2-adrenergic pathway to modify fatty acid skeletal muscle metabolism. To address the physiological relevance of these findings, we demonstrated that this neuromuscular circuit is required to underpin AMPK/ACC signaling activation and fatty acid oxidation after exercise. Last, the selective down-regulation of IL6 receptor in VMH abolished the effects of exercise to sustain AMPK and ACC phosphorylation and fatty acid oxidation in the muscle after exercise. Together, these data demonstrated that the IL6/ERK axis in VMH controls fatty acid metabolism in the skeletal muscle.
Assuntos
Proteínas Quinases Ativadas por AMP , Interleucina-6 , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Ácidos Graxos/metabolismo , Humanos , Hipotálamo/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Camundongos , Músculo Esquelético/metabolismo , OxirreduçãoRESUMO
Obesity is associated with low-grade inflammation and disturbances in hepatic metabolism. This study aimed to investigate the effects of resistance exercise on inflammatory signalling related to IκB kinase (IKK) É protein (IKKÉ) and on hepatic fat accumulation in obese mice. Male Swiss mice were distributed into three groups: control (CTL) fed with standard chow; obese (OB) mice induced by a high-fat diet (HFD); obese exercised (OB + RE) mice fed with HFD and submitted to a resistance exercise training. The resistance exercise training protocol consisted of 20 sets/3 ladder climbs for 8 weeks, three times/week on alternate days. The training overload was equivalent to 70% of the maximum load supported by the rodent. Assays were performed to evaluate weight gain, hepatic fat content, fasting glucose, insulin sensitivity, IKKÉ phosphorylation and proteins related to insulin signalling and lipogenesis in the liver. Mice that received the high-fat diet showed greater adiposity, impaired insulin sensitivity, increased fasting glucose and increased hepatic fat accumulation. These results were accompanied by an increase in IKKÉ phosphorylation and lipogenesis-related proteins such as cluster of differentiation 36 (CD36) and fatty acid synthase (FAS) in the liver of obese mice. In contrast, exercised mice showed lower body weight and adiposity evolution throughout the experiment. In addition, resistance exercise suppressed the effects of the high-fat diet by reducing IKKÉ phosphorylation and hepatic fat content. In conclusion, resistance exercise training improves hepatic fat metabolism and glycaemic homeostasis, which are, at least in part, linked to the anti-inflammatory effect of reduced IKKÉ phosphorylation in the liver of obese mice.
Assuntos
Adiposidade , Quinase I-kappa B , Fígado , Obesidade , Treinamento Resistido , Animais , Dieta Hiperlipídica/efeitos adversos , Glucose/metabolismo , Humanos , Quinase I-kappa B/metabolismo , Resistência à Insulina , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/metabolismo , FosforilaçãoRESUMO
Obesity is a disease characterized by the exacerbated increase of adipose tissue. A possible way to decrease the harmful effects of excessive adipose tissue is to increase the thermogenesis process, to the greater energy expenditure generated by the increase in heat in the body. In adipose tissue, the thermogenesis process is the result of an increase in mitochondrial work, having as substrate H+ ions, and which is related to the increased activity of UCP1. Evidence shows that stress is responsible for increasing the greater induction of UCP1 expression via ß-adrenergic receptors. It is known that physical exercise is an important implement for sympathetic stimulation promoting communication between norepinephrine/epinephrine with membrane receptors. Thus, the present study investigates the influence of short-term strength training (STST) on fatty acid composition, lipolysis, lipogenesis, and browning processes in the subcutaneous adipose tissue (sWAT) of obese mice. For this, Swiss mice were divided into three groups: lean control, obesity sedentary, and obese strength training (OBexT). Obese animals were fed a high-fat diet for 14 weeks. Trained obese animals were submitted to 7 days of strength exercise. It was demonstrated that STST sessions were able to reduce fasting glycemia. In the sWAT, the STST was able to decrease the levels of the long-chain fatty acids profile, saturated fatty acid, and palmitic fatty acid (C16:0). Moreover, it was showed that STST did not increase protein levels responsible for lipolysis, the ATGL, ABHD5, pPLIN1, and pHSL. On the other hand, the exercise protocol decreased the expression of the lipogenic enzyme SCD1. Finally, our study demonstrated that the STST increased browning process-related genes such as PGC-1α, PRDM16, and UCP1 in the sWAT. Interestingly, all these biomolecular mechanisms have been observed independently of changes in body weight. Therefore, it is concluded that short-term strength exercise can be an effective strategy to initiate morphological changes in sWAT.
Assuntos
Ácidos Graxos , Treinamento Resistido , 1-Acilglicerol-3-Fosfato O-Aciltransferase/metabolismo , Tecido Adiposo/metabolismo , Animais , Ácidos Graxos/metabolismo , Humanos , Camundongos , Camundongos Obesos , Obesidade/metabolismo , TermogêneseRESUMO
KEY POINTS: Time-restricted feeding (TRF, in which energy intake is restricted to 8 h/day during the dark phase) alone or combined with aerobic exercise (AE) training can prevent weight gain and metabolic disorders in Swiss mice fed a high-fat diet. The benefits of TRF combined with AE are associated with improved hepatic metabolism and decreased hepatic lipid accumulation. TRF combined with AE training increased fatty acid oxidation and decreased expression of lipogenic and gluconeogenic genes in the liver of young male Swiss mice. TRF combined with AE training attenuated the detrimental effects of high-fat diet feeding on the insulin signalling pathway in the liver. ABSTRACT: Time-restricted feeding (TRF) or physical exercise have been shown to be efficient in the prevention and treatment of metabolic disorders; however, the additive effects of TRF combined with aerobic exercise (AE) training on liver metabolism have not been widely explored. In this study TRF (8 h in the active phase) and TRF combined with AE (TRF+Exe) were compared in male Swiss mice fed a high-fat diet, with evaluation of the effects on insulin sensitivity and expression of hepatic genes involved in fatty acid oxidation, lipogenesis and gluconeogenesis. As in previous reports, we show that TRF alone (eating only between zeitgeber time 16 and 0) was sufficient to reduce weight and adiposity gain, increase fatty acid oxidation and decrease lipogenesis genes in the liver. In addition, we show that mice of the TRF+Exe group showed additional adaptations such as increased oxygen consumption ( VÌO2${\dot V_{{{\rm{O}}_{\rm{2}}}}}$ ), carbon dioxide production ( VÌCO2${\dot V_{{\rm{C}}{{\rm{O}}_{\rm{2}}}}}$ ) and production of ketone bodies (ß-hydroxybutyrate). Also, TRF+Exe attenuated the negative effects of high-fat diet feeding on the insulin signalling pathway (insulin receptor, insulin receptor substrate, Akt), and led to increased fatty acid oxidation (Ppara, Cpt1a) and decreased gluconeogenic (Fbp1, Pck1, Pgc1a) and lipogenic (Srebp1c, Cd36) gene expression in the liver. These molecular results were accompanied by increased glucose metabolism, lower serum triglycerides and reduced hepatic lipid content in the TRF+Exe group. The data presented in this study show that TRF alone has benefits but TRF+Exe has additive benefits and can mitigate the harmful effects of consuming a high-fat diet on body adiposity, liver metabolism and glycaemic homeostasis in young male Swiss mice.
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Resistência à Insulina , Doenças Metabólicas , Animais , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Masculino , Doenças Metabólicas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Aumento de PesoRESUMO
The low-grade inflammation is pivotal in obesity and its comorbidities; however, the inflammatory proteins are out of target for traditional drug therapy. Omega-3 (ω3) fatty acids can modulate the downstream signaling of Toll-like receptor (TLR) and tumor necrosis factor-α receptor (TNFα) through GPR120, a G-protein-coupled receptor, a mechanism not yet elucidated in humans. This work aims to investigate if the ω3 supplementation, at a feasible level below the previously recommended level in the literature, is enough to disrupt the inflammation and endoplasmic reticulum stress (ER-stress), and also if in acute treatment (3 h) ω3 can activate the GPR120 in peripheral blood mononuclear cells (PBMC) and leukocytes from overweight non-alcoholic fatty liver disease (NAFLD) participants. The R270H variant of the Ffar4 (GPR120 gene) will also be explored about molecular responses and blood lipid profiles. A triple-blind, prospective clinical trial will be conducted in overweight men and women, aged 19-75 years, randomized into placebo or supplemented (2.2 g of ω3 [EPA+DHA]) groups for 28 days. For sample calculation, it was considered the variation of TNFα protein and a 40% dropout rate, obtaining 22 individuals in each group. Volunteers will be recruited among patients with NAFLD diagnosis. Anthropometric parameters, food intake, physical activity, total serum lipids, complete fatty acid blood profile, and glycemia will be evaluated pre- and post-supplementation. In the PBMC and neutrophils, the protein content and gene expression of markers related to inflammation (TNFα, MCP1, IL1ß, IL6, IL10, JNK, and TAK1), ER-stress (ATF1, ATF6, IRE1, XBP1, CHOP, eIF2α, eIF4, HSP), and ω3 pathway (GPR120, ß-arrestin2, Tab1/2, and TAK1) will be evaluated using Western blot and RT-qPCR. Participants will be genotyped for the R270H (rs116454156) variant using the TaqMan assay. It is hypothesized that attenuation of inflammation and ER-stress signaling pathways in overweight and NAFLD participants will be achieved through ω3 supplementation through binding to the GPR120 receptor. TRIAL REGISTRATION: ClinicalTrials.gov #RBR-7x8tbx. Registered on May 10, 2018, with the Brazilian Registry of Clinical Trials.
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Hepatopatia Gordurosa não Alcoólica , Estresse do Retículo Endoplasmático , Humanos , Inflamação , Leucócitos Mononucleares , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Sobrepeso , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Hepatic steatosis is directly associated with hepatic inflammation and insulin resistance, which is correlated with hyperglycemia and type 2 diabetes mellitus (T2DM). Aerobic and strength training have been pointed out as efficient strategies against hepatic steatosis. However, little is known about the effects of the combination of those two protocols on hepatic steatosis. Therefore, this study aimed to evaluate the impact of short-term combined training (STCT) on glucose homeostasis and in the synthesis and oxidation of fat in the liver of obesity-induced mice with hepatic steatosis. Swiss mice were distributed into three groups: control lean (CTL), sedentary obese (OB), and combined training obese (CTO). The CTO group performed the STCT protocol, which consisted of strength and aerobic exercises in the same session. The protocol lasted seven days. The CTO group reduced the glucose levels and fatty liver when compared to the OB group. Interestingly, these results were observed even without reductions in body adiposity. CTO group also showed increased hepatic insulin sensitivity, with lower hepatic glucose production (HGP). STCT reduced the expression of the lipogenic genes Fasn and Scd1 and hepatic inflammation, as well as increased the ACC phosphorylation and the oxidative genes Cpt1a and Ppara, reverting the complications caused by obesity. Since this protocol increased lipid oxidation and reduced hepatic lipogenesis, regardless of body fat mass decrease, it can be considered an effective non-pharmacological strategy for the treatment of hepatic steatosis.
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Fígado Gorduroso/metabolismo , Fígado Gorduroso/terapia , Resistência à Insulina/fisiologia , Insulina/metabolismo , Fígado/metabolismo , Condicionamento Físico Animal/fisiologia , Animais , Dieta Hiperlipídica/efeitos adversos , Teste de Esforço/métodos , Masculino , Camundongos , Obesidade/metabolismo , Obesidade/terapia , Condicionamento Físico Animal/métodosRESUMO
Aging is characterized by several physiological changes in the human body, such as the remodeling/redistribution of body fat, highlighted by the increase in fat in the abdominal region due to reduced fat in the peripheral limbs. Abdominal fat is related to metabolic complications and an increased risk for developing diseases such as obesity, type 2 diabetes mellitus, and hypertension. Understanding this process is crucial for developing new therapeutic strategies able to mitigate its impact. This redistribution of fat has been associated with lower activation of brown adipose tissue over the years of life. Brown adipose tissue differs from white adipose tissue, mainly because it produces heat, increasing energy expenditure. Current evidence points to morphological and functional changes in mitochondria during aging, a key mechanism for understanding the dysmetabolic and pro-inflammatory phenotype associated with senescence. Therefore, this minireview will focus on how aging-induced mitochondrial changes are involved in the remodeling/redistribution of body fat.
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Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Envelhecimento , Metabolismo Energético/fisiologia , Mitocôndrias/metabolismo , Envelhecimento/metabolismo , Envelhecimento/patologia , Distribuição da Gordura Corporal , HumanosRESUMO
Interventions that can modulate subcutaneous white adipose tissue (scWAT) function, such as exercise training and nutritional components, like taurine, modulate the inflammatory process, therefore, may represent strategies for obesity treatment. We investigated the effects of taurine supplementation in conjunction with exercise on inflammatory and oxidative stress markers in plasma and scWAT of obese women. Sixteen obese women were randomized into two groups: Taurine supplementation group (Tau, n = 8) and Taurine supplementation + exercise group (Tau + Exe, n = 8). The intervention was composed of daily taurine supplementation (3 g) and exercise training for 8 weeks. Anthropometry, body fat composition, and markers of inflammatory and oxidative stress were determined in plasma and scWAT biopsy samples before and after the intervention. We found that, although taurine supplementation increased taurine plasma levels, no changes were observed for the anthropometric characteristics. However, Tau alone decreased interleukin-6 (IL-6), and in conjunction with exercise (Tau + Exe), increased anti-inflammatory interleukins (IL-15 and IL10), followed by reduced IL1ß gene expression in the scWAT of obese women. Tau and Tau + Exe groups presented reduced adipocyte size and increased connective tissue and multilocular droplets. In conclusion, taurine supplementation in conjunction with exercise modulated levels of inflammatory markers in plasma and scWAT, and improved scWAT plasticity in obese women, promoting protection against obesity-induced inflammation. TRN NCT04279600 retrospectively registered on August 18, 2019.
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Tecido Adiposo Branco/fisiologia , Citocinas/sangue , Suplementos Nutricionais , Exercício Físico , Obesidade/terapia , Gordura Subcutânea/fisiologia , Taurina/administração & dosagem , Tecido Adiposo , Adulto , Biomarcadores/sangue , Composição Corporal , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/patologia , Adulto JovemRESUMO
Obesity is a chronic, non-transmissible and multifactorial disease commonly associated with systemic inflammation and damage to health. This disorder has been pointed out as leading to the development of a diversity of eye diseases and, consequently, damage to visual acuity. More specifically, cardiometabolic risk is associated with lacrimal gland dysfunctions, since it changes the inflammatory profile favoring the development and worsening of dry eye disease. In more severe and extreme cases, obesity, inflammation, and diabetes mellitus type 2 can trigger the total loss of vision. In this scenario, besides its numerous metabolic functions, clusterin, an apolipoprotein, has been described as protective to the ocular surface through the seal mechanism. Thus, the current review aimed to explain the role of clusterin in dry eye disease that can be triggered by obesity and diabetes.
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Clusterina/genética , Diabetes Mellitus Tipo 2/genética , Síndromes do Olho Seco/genética , Obesidade/genética , Apolipoproteínas/genética , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Síndromes do Olho Seco/etiologia , Síndromes do Olho Seco/patologia , Olho/metabolismo , Olho/patologia , Humanos , Inflamação/etiologia , Inflamação/genética , Inflamação/patologia , Obesidade/complicações , Obesidade/patologiaRESUMO
The hypothalamus plays a critical role in the control of food consumption and energy expenditure. Fatty diets can elicit an inflammatory response in specific hypothalamic cells, including astrocytes, tanycytes, and microglia, disrupting anorexigenic signals in region-specific hypothalamic neurons, contributing to overeating and body weight gain. In this study, we present an update regarding the knowledge of the effects of physical exercise on inflammatory signaling and circuits to control hunger in the hypothalamus in obesity conditions. To try to understand changes in the hypothalamus, we review the use of magnetic resonance/anorexigenic hormone analysis in humans, as well as in animal models to explore the physiological and molecular mechanism by which exercise modulates satiety signals, such as the central anti-inflammatory response, myokine delivery from skeletal muscle, and others. The accumulation of scientific evidence in recent years allows us to understand that exercise contributes to weight control, and it is managed by mechanisms that go far beyond "burning calories."
Assuntos
Exercício Físico , Hipotálamo , Saciação , Animais , Humanos , Inflamação , ObesidadeRESUMO
PURPOSE: To evaluate the effects of taurine supplementation associated or not with chronic exercise on body composition, mitochondrial function, and expression of genes related to mitochondrial activity and lipid oxidation in the subcutaneous white adipose tissue (scWAT) of obese women. METHODS: A randomized and double-blind trial was developed with 24 obese women (BMI 33.1 ± 2.9 kg/m2, 32.9 ± 6.3 y) randomized into three groups: Taurine supplementation group (Tau, n = 8); Exercise group (Ex, n = 8); Taurine supplementation + exercise group (TauEx, n = 8). The intervention was composed of 3 g of taurine or placebo supplementation and exercise training for eight weeks. Anthropometry, body fat composition, indirect calorimetry, scWAT biopsy for mitochondrial respiration, and gene expression related to mitochondrial activity and lipid oxidation were assessed before and after the intervention. RESULTS: No changes were observed for the anthropometric characteristics. The Ex group presented an increased resting energy expenditure rate, and the TauEx and Ex groups presented increased lipid oxidation and a decreased respiratory quotient. Both trained groups (TauEx and Ex) demonstrated improved scWAT mitochondrial respiratory capacity. Regarding mitochondrial markers, no changes were observed for the Tau group. The TauEx group had higher expression of CIDEA, PGC1a, PRDM16, UCP1, and UCP2. The genes related to fat oxidation (ACO2 and ACOX1) were increased in the Tau and Ex groups, while only the TauEx group presented increased expression of CPT1, PPARa, PPARγ, LPL, ACO1, ACO2, HSL, ACOX1, and CD36 genes. CONCLUSION: Taurine supplementation associated with exercise improved lipid metabolism through the modulation of genes related to mitochondrial activity and fatty acid oxidation, suggesting a browning effect in the scWAT of obese women.