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1.
Toxicol Lett ; 318: 12-21, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31622651

RESUMO

Maternal smoking during pregnancy and lactation is associated with increased fat mass in the offspring, but the mechanism by which this occurs is not fully understood. Our study focused on the relationships among maternal nicotine exposure, adipose angiogenesis and adipose tissue function in female offspring. Pregnant rats were randomly assigned to nicotine or control groups. Microvascular density, lipid metabolism and α7nAChR-Egr1-FGF2 signaling pathway genes/proteins were tested in 4-, 12- and 26-week female offspring. In vitro, nicotine concentration- and time-response experiments were conducted in 3T3-L1. Lipid metabolism and α7nAChR-Egr1-FGF2 signaling pathway genes/proteins were tested. The conditioned media of differentiated 3T3-L1 treated with nicotine were used to observe tube formation in human umbilical vein endothelial cells (HUVECs). Nicotine-exposed females presented higher adipose microvascular density. The gene expression of α7nAChR, Egr1 and FGF2 was significantly increased in gonadal white adipose tissue (gWAT) and inguinal subcutaneous WAT (igSWAT) of nicotine-exposed females at 4 weeks of age. The protein expression of α7nAChR, Egr1 and FGF2 was increased in gWAT and igSWAT of nicotine-exposed females at 4 weeks of age, and increased in gWAT at 26 weeks. In vitro, nicotine increased the expression of lipid metabolism and α7nAChR-Egr1-FGF2 signaling pathway genes/proteins in a concentration- and time-dependent manner. In the tube formation experiment, adipocytes affected by nicotine promoted HUVEC angiogenesis. Therefore, maternal nicotine exposure promoted the early angiogenesis of adipose tissue via the α7nAChR-Egr1-FGF2 signaling pathway, and this angiogenesis mechanism was associated with increased adipogenesis in adipose tissue of female offspring.


Assuntos
Adipócitos/efeitos dos fármacos , Tecido Adiposo Branco/irrigação sanguínea , Neovascularização Fisiológica/efeitos dos fármacos , Nicotina/toxicidade , Agonistas Nicotínicos/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Feminino , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Exposição Materna , Camundongos , Gravidez , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/metabolismo
2.
Int J Nanomedicine ; 14: 7795-7808, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576124

RESUMO

Background: Endogenously expressed microRNAs (miRNAs) have attracted attention as important regulators in post-transcriptionally controlling gene expression of various physiological processes. As miRNA dysregulation is often associated with various disease patterns, such as obesity, miRNA-27a might therefore be a promising candidate for miRNA mimic replacement therapy by inhibiting adipogenic marker genes. However, application of naked nucleic acids faces some limitations concerning poor enzymatic stability, bio-membrane permeation and cellular uptake. To overcome these obstacles, the development of appropriate drug delivery systems (DDS) for miRNAs is of paramount importance. Methods: In this work, a triple combination of atomic force microscopy (AFM), brightfield (BF) and fluorescence microscopy was used to trace the cellular adhesion of N-TER peptide-nucleic acid complexes followed by time-dependent uptake studies using confocal laser scanning microscopy (cLSM). To reveal the biological effect of miRNA-27a on adipocyte development after transfection treatment, Oil-Red-O (ORO)- staining was performed to estimate the degree of in lipid droplets accumulated ORO in mature adipocytes by using light microscopy images as well as absorbance measurements. Results: The present findings demonstrated that amphipathic N-TER peptides represent a suitable DDS for miRNAs by promoting non-covalent complexation through electrostatic interactions between both components as well as cellular adhesion of the N-TER peptide - nucleic acid complexes followed by uptake across cell membranes and intracellular release of miRNAs. The anti-adipogenic effect of miRNA-27a in 3T3-L1 cells could be detected in mature adipocytes by reduced lipid droplet formation. Conclusion: The present DDS assembled from amphipathic N-TER peptides and miRNAs is capable of inducing the anti-adipogenic effect of miRNA-27a by reducing lipid droplet accumulation in mature adipocytes. With respect to miRNA mimic replacement therapies, this approach might provide new therapeutic strategies to prevent or treat obesity and obesity-related disorders.


Assuntos
Sistemas de Liberação de Medicamentos , MicroRNAs/metabolismo , Peptídeos/química , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/metabolismo , Adipogenia , Sequência de Aminoácidos , Animais , Adesão Celular , Gotículas Lipídicas/metabolismo , Camundongos , MicroRNAs/genética , Ácidos Nucleicos Peptídicos/química , Transfecção
3.
J Biol Regul Homeost Agents ; 33(5): 1327-1335, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31487982

RESUMO

The glucose transporter 4 (GLUT4) translocation is a vital link of insulin-induced glucose uptake in adipose tissue and skeletal muscle. It is an important topic in anti-diabetic research to explore novel agents to facilitate the role of insulin. The aim of this study was to verify the hypothesis that neuropeptide galanin may enhance insulin-induced GLUT4 translocation to increase glucose uptake in adipose tissue of type 2 diabetic models. Insulin and/or galanin were injected respectively or cooperatively into type 2 diabetic rats once a day for fifteen days. The results showed that administration of galanin significantly enhanced insulin-induced GLUT4 and vesicle-associated membrane protein 2 (VAMP2) translocation, Akt phosphorylation and glucose uptake, but not GLUT4 mRNA and protein expression levels in adipose cells. The beneficial roles of galanin on insulin-induced events may be blocked by MK-2206, an Akt inhibitor, indicating that the Akt phosphorylation is essential for promoting impact of galanin on the insulin-induced events. These results suggest that galanin may benefit insulin-induced GLUT4 and VAMP2 translocation, and subsequent glucose uptake via the activated Akt-VAMP2-GLUT4 pathway in adipose cells. These findings deepen our understanding of the anti-diabetic effect of galanin and its mechanism.


Assuntos
Adipócitos/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Galanina/farmacologia , Transportador de Glucose Tipo 4/metabolismo , Insulina/farmacologia , Animais , Diabetes Mellitus Experimental/metabolismo , Glucose/metabolismo , Transporte Proteico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Proteína 2 Associada à Membrana da Vesícula/metabolismo
4.
Nat Med ; 25(9): 1385-1389, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501613

RESUMO

The worldwide obesity epidemic1 makes it important to understand how lipid turnover (the capacity to store and remove lipids) regulates adipose tissue mass. Cross-sectional studies have shown that excess body fat is associated with decreased adipose lipid removal rates2,3. Whether lipid turnover is constant over the life span or changes during long-term weight increase or loss is unknown. We determined the turnover of fat cell lipids in adults followed for up to 16 years, by measuring the incorporation of nuclear bomb test-derived 14C in adipose tissue triglycerides. Lipid removal rate decreases during aging, with a failure to reciprocally adjust the rate of lipid uptake resulting in weight gain. Substantial weight loss is not driven by changes in lipid removal but by the rate of lipid uptake in adipose tissue. Furthermore, individuals with a low baseline lipid removal rate are more likely to remain weight-stable after weight loss. Therefore, lipid turnover adaptation might be important for maintaining pronounced weight loss. Together these findings identify adipose lipid turnover as an important factor for the long-term development of overweight/obesity and weight loss maintenance in humans.


Assuntos
Envelhecimento/metabolismo , Peso Corporal/genética , Obesidade/metabolismo , Ganho de Peso/genética , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Adolescente , Adulto , Envelhecimento/genética , Envelhecimento/patologia , Peso Corporal/fisiologia , Radioisótopos de Carbono/química , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Metabolismo dos Lipídeos/genética , Lipídeos/genética , Masculino , Obesidade/genética , Obesidade/patologia , Sobrepeso/genética , Sobrepeso/metabolismo , Sobrepeso/patologia , Triglicerídeos/metabolismo , Perda de Peso/genética
5.
J Agric Food Chem ; 67(37): 10321-10329, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31419115

RESUMO

Pterostilbene (PTS) is a phenolic compound with diverse pharmacologic activities. However, its potential for inhibiting obesity-related colorectal cancer (CRC) remains unclear. Our study evaluated the mechanism of inhibitory effects of PTS on adipocyte conditioned-medium (aCM)-induced malignant transformation in HT-29 colorectal adenocarcinoma cells. The results demonstrated that PTS could downregulate the expression of aCM-induced fatty acid-binding protein 5 (FABP5) and prometastatic factors such as vascular endothelial growth factor, matrix metalloproteinase-2 (MMP2), MMP9, and extracellular tumor necrosis factor α via inhibiting aCM-induced nuclear factor-kappa B (NF-κB), ß-catenin, and peroxisome proliferator-activated receptor γ (PPAR-γ). Moreover, PTS can suppress aCM-stimulated phosphoinositide 3-kinase (PI3K), protein kinase B (Akt), p38 mitogen-activated protein kinase (p38 MAPK), extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinases 1/2 (JNK 1/2) signaling pathways activation that are upstream of NF-κB, ß-catenin, and PPAR-γ. Therefore, we suggest that PTS could alleviate adiposity-induced metastasis in CRC via inhibiting cell migration through downregulating FABP5 gene expression.


Assuntos
Adipócitos/metabolismo , Movimento Celular/efeitos dos fármacos , Neoplasias Colorretais/fisiopatologia , Meios de Cultivo Condicionados/química , Proteínas de Ligação a Ácido Graxo/metabolismo , Estilbenos/farmacologia , Células 3T3 , Animais , Linhagem Celular , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Meios de Cultivo Condicionados/metabolismo , Regulação para Baixo/efeitos dos fármacos , Proteínas de Ligação a Ácido Graxo/genética , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , NF-kappa B/genética , NF-kappa B/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Fitoterapia ; 137: 104250, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31271784

RESUMO

Obesity is associated with a number of metabolic disorders. Lipolysis is the initial step in the metabolism of lipids stored in adipocytes and is therefore considered a therapeutic target for obesity. Quassinoids are unique terpenes found in plants of the Simaroubaceae family, which were recently reported to have lipolytic activity and to suppress weight gain. Brucea javanica is a plant employed in traditional medicines in Asia, which is known to contain various quassinoids. Here, we investigated the lipolytic activity of B. javanica extracts, and identified six quassinoids: brucein A, brucein B, brucein C, 3'-hydroxybrucein A, brusatol, and bruceantinol, which represent the bioactive principals. The quassinoids contained in B. javanica demonstrated lipolytic activity at nanomolar concentrations, which were an order of magnitude lower than those of the previously reported quassinoids, suggesting that they may be useful for the treatment of obesity.


Assuntos
Adipócitos/efeitos dos fármacos , Brucea/química , Lipólise/efeitos dos fármacos , Quassinas/farmacologia , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Frutas/química , Camundongos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Quassinas/isolamento & purificação , Sementes/química
7.
Nat Commun ; 10(1): 2936, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31270323

RESUMO

ß-Arrestins are major regulators of G protein-coupled receptor-mediated signaling processes. Their potential roles in regulating adipocyte function in vivo remain unexplored. Here we report the novel finding that mice lacking ß-arrestin-2 (barr2) selectively in adipocytes show significantly reduced adiposity and striking metabolic improvements when consuming excess calories. We demonstrate that these beneficial metabolic effects are due to enhanced signaling through adipocyte ß3-adrenergic receptors (ß3-ARs), indicating that barr2 represents a potent negative regulator of adipocyte ß3-AR activity in vivo. Interestingly, essentially all beneficial metabolic effects caused by adipocyte barr2 deficiency are absent in adipocyte barr2-PRDM16 double KO mice, indicating that the metabolic improvements caused by the lack of barr2 in adipocytes are mediated by the browning/beiging of white adipose tissue. Our data support the novel concept that 'G protein-biased' ß3-AR agonists that do not promote ß3-AR/barr2 interactions may prove useful for the treatment of obesity and related metabolic disorders.


Assuntos
Adipócitos/metabolismo , Metabolismo Energético , Glucose/metabolismo , beta-Arrestina 2/metabolismo , Animais , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Homeostase , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Adrenérgicos beta 3/genética , Receptores Adrenérgicos beta 3/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , beta-Arrestina 2/genética
8.
DNA Cell Biol ; 38(9): 945-954, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31355674

RESUMO

Domestic cattle are an important type of livestock, with beef production playing a major role in the agricultural economy. Adipocyte levels and fat content are interrelated, with meat quality being highly dependent on its fat content and distribution. Acyl-CoA synthetases of long-chain (ACSL) fatty acids (FAs) play an integral role in virtually every metabolic pathway in mammalian biochemistry, including complex lipid biosynthesis, protein modification, and ß-oxidation processes. ACSL3 activity is also known to be associated with adipocyte differentiation; however, its biological mechanism of action is currently unclear. Gene expression in subcutaneous preadipocytes isolated from subcutaneous deposits of Chinese Red Steppe cattle has been studied using in vitro cell transfection, real-time polymerase chain reaction and western blot analysis. The lipid and triglyceride contents of lipid droplets have also been measured to verify the levels of gene expression. These combined studies show that ACSL3 is induced during adipocyte differentiation, with its overexpression promoting an increase in the triglyceride content of lipid droplets. Furthermore, mRNA and protein expression levels for adipocyte differentiation marker genes, such as peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein alpha (C/EBPα), were markedly increased during mature adipocyte cell differentiation. Knockdown of ACSL3 expression using ACSL3 small interfering RNAs (siRNAs) resulted in a decrease in lipid content of cattle adipocytes, providing further evidence that ACSL3 plays a key role in the differentiation process.


Assuntos
Adipócitos/citologia , Adipogenia , Bovinos/genética , Coenzima A Ligases/genética , Adipócitos/metabolismo , Animais , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Células Cultivadas , Coenzima A Ligases/metabolismo , PPAR gama/genética , PPAR gama/metabolismo
9.
Cytogenet Genome Res ; 158(3): 133-144, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31272101

RESUMO

Bone morphogenetic protein 2 (BMP2) can mediate the signaling of R-Smads and regulate different biological functions, including adipocyte differentiation. Long noncoding RNAs (lncRNAs) can be involved in many important biological processes, including fat metabolism, as miRNA sponges. This study aimed to investigate the molecular mechanism of fat deposition and to provide useful information for the prevention and treatment of lipid-related diseases. lncRNA sequencing was performed to compare and analyze, for the first time, the expression of lncRNAs in BMP2-induced and non-BMP2-induced preadipocytes from Junmu1 pigs. In addition, functional annotation and enrichment analysis of differentially expressed lncRNA target genes were carried out. lncRNAs and mRNAs were compared and analyzed. lncRNAs were identified that may regulate adipogenesis and lipid metabolism. The results give a theoretical basis for further studies on fat deposition mechanisms and provide potential therapeutic targets for metabolic diseases.


Assuntos
Adipócitos/efeitos dos fármacos , Proteína Morfogenética Óssea 2/farmacologia , Diferenciação Celular/efeitos dos fármacos , RNA Longo não Codificante/análise , Células-Tronco/efeitos dos fármacos , Suínos/genética , Transcriptoma/genética , Adipócitos/citologia , Adipócitos/metabolismo , Animais , RNA Longo não Codificante/genética , Análise de Sequência de RNA , Células-Tronco/citologia , Células-Tronco/metabolismo , Triglicerídeos/metabolismo
10.
J Anim Sci ; 97(7): 2837-2849, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31267132

RESUMO

Ketosis is a major metabolic disorder of high-yielding dairy cows during the transition period. Although metabolic adaptations of the adipose tissue are critical for a successful transition, beyond lipolysis, alterations within adipose tissue during ketosis are not well known. The objective of this study was to investigate the adipose tissue proteome of healthy or ketotic postpartum cows to gain insights into biological adaptations that may contribute to disease outcomes. Adipose tissue biopsy was collected on 5 healthy and 5 ketotic cows at 17 (±4) d postpartum and ketosis was defined according to the clinical symptoms and serum ß-hydroxybutyrate concentration. Morphology micrographs stained by hematoxylin-eosin showed that adipocytes were smaller in ketotic cows than in healthy cows. The isobaric tag for relative and absolute quantification was applied to quantitatively identify differentially expressed proteins (DEP) in the adipose tissue. We identified a total of 924 proteins, 81 of which were differentially expressed between ketotic and healthy cows (P < 0.05 and fold changes >1.5 or <0.67). These DEP included enzymes and proteins associated with various carbohydrate, lipid, and amino acid metabolism processes. The top pathways differing between ketosis and control cows were glycolysis/gluconeogenesis, glucagon signaling pathway, cysteine and methionine metabolism, biosynthesis of amino acids, and the cGMP-PKG signaling pathway. The identified DEP were further validated by western blot and co-immunoprecipitation assay. Key enzymes associated with carbohydrate metabolism such as pyruvate kinase 2, pyruvate dehydrogenase E1 component subunit α), lactate dehydrogenase A , phosphoglucomutase 1, and 6-phosphofructokinase 1 were upregulated in ketotic cows. The expression and phosphorylation state of critical regulators of lipolysis such as perilipin-1 and hormone-sensitive lipase were also upregulated in ketotic cows. Furthermore, key proteins involved in maintaining innate immune response such as lipopolysaccharide binding protein and regakine-1 were downregulated in ketotic cows. Overall, data indicate that ketotic cows during the transition period have altered carbohydrate, lipid metabolism, and impaired immune function in the adipose tissue. This proteomics analysis in adipose tissue of ketotic cows identified several pathways and proteins that are components of the adaptation to ketosis.


Assuntos
Adaptação Fisiológica , Doenças dos Bovinos/metabolismo , Cetose/veterinária , Leite/metabolismo , Proteoma , Proteômica , Ácido 3-Hidroxibutírico/sangue , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Animais , Biomarcadores/análise , Metabolismo dos Carboidratos , Bovinos , Feminino , Regulação da Expressão Gênica , Imunidade Inata , Cetose/metabolismo , Lactação , Metabolismo dos Lipídeos , Redes e Vias Metabólicas , Fosforilação , Período Pós-Parto , Transdução de Sinais
11.
J Agric Food Chem ; 67(32): 8839-8846, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31334651

RESUMO

Natural products are one of the main sources for discovering new lead compounds. We previously reported that cinnamon extract has a promising effect in regulating lipid tissue volume and insulin sensitivity in vivo. However, its effective component and the underlying mechanism are not known. In the present study, we analyzed the effect of different components of cinnamon on regulating insulin sensitivity in 3T3-L1 adipocytes. Functional assay revealed that, of the six major components of cinnamon extracts, the B-type procyanidin, procyanidin C1, improves the differentiation of 3T3-L1 cells (TG content: 1.10 ± 0.09 mM at a dosage of 25 µM vs 0.67 ± 0.02 mM in vehicle group, p < 0.001) and promotes insulin-induced glucose uptake (8.58 ± 1.43 at a dosage of 25 µM vs 3.05 ± 1.24 in vehicle group, p < 0.001). Mechanism studies further suggested that procyanidin C1 activates the AKT-eNOS pathway, thus up-regulating glucose uptake and enhancing insulin sensitivity in mature adipocytes. Taken together, our study identified B-type procyanidin C1, a component of cinnamon extract, that stimulates preadipocyte differentiation and acts as a potential insulin action enhancer through the AKT-eNOS pathway in mature adipocytes.


Assuntos
Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Biflavonoides/farmacologia , Catequina/farmacologia , Cinnamomum zeylanicum/química , Insulina/metabolismo , Extratos Vegetais/farmacologia , Proantocianidinas/farmacologia , Células 3T3-L1 , Adipócitos/citologia , Animais , Transporte Biológico/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Glucose/metabolismo , Camundongos , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo
12.
Int J Mol Sci ; 20(13)2019 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-31261892

RESUMO

BACKGROUND: Angiotensin II (Ang II), released by the renin-angiotensin-aldosterone system (RAAS), contributes to the modulatory role of the RAAS in adipose tissue dysfunction. Investigators have shown that inhibition of AngII improved adipose tissue function and insulin resistance in mice with metabolic syndrome. Heme Oxygenase-1 (HO-1), a potent antioxidant, has been demonstrated to improve oxidative stress and adipocyte phenotype. Molecular effects of high oxidative stress include suppression of sirtuin-1 (SIRT1), which is amenable to redox manipulations. The mechanisms involved, however, in these metabolic effects of the RAAS remain incompletely understood. HYPOTHESIS: We hypothesize that AngII-induced oxidative stress has the potential to suppress adipocyte SIRT1 via down regulation of HO-1. This effect of AngII will, in turn, upregulate mineralocorticoid receptor (MR). The induction of HO-1 will rescue SIRT1, hence improving oxidative stress and adipocyte phenotype. METHODS AND RESULTS: We examined the effect of AngII on lipid accumulation, oxidative stress, and inflammatory cytokines in mouse pre-adipocytes in the presence and absence of cobalt protoporphyrin (CoPP), HO-1 inducer, tin mesoporphyrin (SnMP), and HO-1 inhibitor. Our results show that treatment of mouse pre-adipocytes with AngII increased lipid accumulation, superoxide levels, inflammatory cytokine levels, interleukin-6 (IL-6) and tumor necrosis factor α (TNFα), and adiponectin levels. This effect was attenuated by HO-1 induction, which was further reversed by SnMP, suggesting HO-1 mediated improvement in adipocyte phenotype. AngII-treated pre-adipocytes also showed upregulated levels of MR and suppressed SIRT1 that was rescued by HO-1. Subsequent treatment with CoPP and SIRT1 siRNA in mouse pre-adipocytes increased lipid accumulation and fatty acid synthase (FAS) levels, suggesting that beneficial effects of HO-1 are mediated via SIRT1. CONCLUSION: Our study demonstrates for the first time that HO-1 has the ability to restore cellular redox, rescue SIRT1, and prevent AngII-induced impaired effects on adipocytes and the systemic metabolic profile.


Assuntos
Adipócitos/metabolismo , Angiotensina II/farmacologia , Heme Oxigenase (Desciclizante)/metabolismo , Estresse Oxidativo , Sirtuína 1/metabolismo , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Animais , Citocinas/metabolismo , Ácido Graxo Sintases/metabolismo , Heme Oxigenase (Desciclizante)/antagonistas & inibidores , Metabolismo dos Lipídeos , Camundongos , Receptores de Mineralocorticoides/metabolismo
13.
Int J Mol Sci ; 20(13)2019 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-31261958

RESUMO

Natural bioactive compounds may be used in obese patients because of their ability to impact on various key mechanisms involved in the complex pathophysiological mechanisms of such condition. The aim of this study was to investigate the effect of a Mangifera indica L. leaf extract (MLE) on adipogenic differentiation of murine preadipocyte cells. 3T3-L1 cells were treated during their differentiation with various concentrations of (Mangifera indica L.) leaves extract (MLE) (750, 380, 150, 75 and 35 µg) in order to assess their lipid content, adiponectin production, expression profile of genes involved in lipid metabolism, oxidative stress and inflammation. Our results showed that MLE was particularly enriched in polyphenols (46.30 ± 0.083 mg/g) and that pharmacological treatment of cells resulted in a significant increase of adiponectin levels and reduction of intracellular lipid content. Consistently with these results, MLE resulted in a significant decrease of the expression of genes involved in lipid metabolism (FAS, PPARG, DGAT1, DGAT2, and SCD-1). In conclusion, our results suggest that MLE may represent a possible pharmacological tool for obese or metabolic syndrome patients.


Assuntos
Adipócitos/efeitos dos fármacos , Adipogenia , Adiponectina/metabolismo , Antioxidantes/farmacologia , Mangifera/química , Extratos Vegetais/farmacologia , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Antioxidantes/química , Metabolismo dos Lipídeos , Camundongos , Estresse Oxidativo , Extratos Vegetais/química , Folhas de Planta/química , Polifenóis/análise , Xantonas/análise
14.
Zhonghua Gan Zang Bing Za Zhi ; 27(6): 450-456, 2019 Jun 20.
Artigo em Chinês | MEDLINE | ID: mdl-31357762

RESUMO

Objective: To observe the effect of differentiated mature adipocytes on hepatic steatosis and aquaporin-9 (AQP9) expressions in HepG2 cells and further explore its possible mechanism of action. Methods: Human preadipocytes were cultured and differentiated to full maturity. HepG2 cells were co-cultured with non-differentiated adipocytes and differentiated mature adipocytes for 48 h, and then labeled as control group and experimental group. Oil red O staining and intracellular triglyceride content were performed on co-cultured HepG2 cells and simultaneous changes in phosphatidylinositol 3-kinase (PI3K) - serine/threonine kinase (Akt) signaling pathway, and AQP9 mRNA and protein levels were detected. The experimental group was co-cultured with recombinant human insulin-like growth factor-I (IGF-I), with the addition of 100ng/ml PI3K-Akt pathway agonist, labeled as experimental group + IGF-I group. The activation of PI3K-Akt pathway was verified by Western blotting (WB). The expression of AQP9 was detected by RT-q PCR and WB. The recombinant lentivirus LV-AQP9 or empty-loaded virus LV-PWPI was transfected with HepG2 cells by recombinant lentiviral transfection tecnique, and labeled as HepG2-AQP9 and HepG2-PWPI. The transfection efficiency was assessed by confocal laser scanning microscopy and RT-qPCR and WB detected the change of AQP9 expression level after virus transfection. Afterwards, the stable over-expressed HepG2-AQP9 cells and the empty-loaded HepG2-PWPI cells were co-cultured with differentiated mature adipocytes for 48h, and labeled as HepG2-AQP9 co-culture group, and then intracellular triglyceride content were detected with Oil red O staining. Finally, IGF-I was added to the HepG2-AQP9 co-culture group, which was recorded as HepG2-AQP9 co-culture + IGF-I group. Intracellular triglyceride content was detected with Oil red O staining, and WB verified PI3K-Akt signaling pathway activation and changes in AQP9 mRNA and protein levels. A t-test was used to compare the two independent samples. Results: The intracellular lipid droplets and triglyceride content (0.052 ± 0.005) in the experimental group was increased significantly than the control group (0.033 ± 0.003) (t= 5.225,P= 0.006), suggesting that adipocyte co-culture had induced steatosis in HepG2 cells. RT-qPCR and WB results indicated that the expression levels of AQP9 mRNA (3.615 ± 0.330) and protein levels (0.072 ± 0.005) in the experimental group were significantly higher than the control group (t= 13.708, 11.225,P= 0.005, < 0.001). WB results showed that the expression level of phosphorylated Akt (p-Akt) protein (0.116±0.003) in the experimental group was significantly lower than the control group (0.202 ± 0.003) (t= 27.136,P< 0.001). The total Akt protein was constant, and the p-Akt/total Akt (0.182 ± 0.017)was significantly lower than the control group (0.327 ± 0.019) (t= 2.431,P= 0.001), suggesting that adipocyte co-culture had inhibited PI3K- Akt signaling pathway in HepG2 cells and up-regulated the expression level of AQP9. WB results indicated that the expression level of p-Akt protein (0.194 ± 0.021) in the experimental group + IGF-I group was significantly higher than the experimental group (0.132 ± 0.003) (t= 5.082,P= 0.007). The total Akt protein was constant, and the p-Akt/total Akt (0.281 ± 0.009) was significantly higher than the control group (0.184 ± 0.132) (t= 10.311,P< 0.001). Simultaneously, RT-qPCR and WB results indicated that the expression levels of AQP9 mRNA (0.327 ± 0.347) and protein levels (0.042 ± 0.004) in the experimental group + IGF-I group were significantly lower than the experimental group (t= 33.573, 5.598,P< 0.001, 0.005), suggesting that adipocyte co-culture had possibility to regulate the expression level of AQP9 through the PI3K-Akt pathway. Confocal laser microscopy analysis showed that the transfection efficiency was more than 90%. RT-q PCR and WB results indicated that the expression levels of AQP9 mRNA and protein levels (0.373 ± 0.221) in HepG2-AQP9 group were significantly higher than HepG2-PWPI group (t=14.953, 28.931,P= 0.002 and 0.000), suggesting that the stable overexpression of AQP9 cell line was successfully constructed. The intracellular lipid droplets and triglyceride content in HepG2-AQP9 co-culture group was significantly increased (t= 5.478, 5.369,P= 0.005) than HepG2-PWPI co-culture group and HepG2-AQP9 co-culture+ IGF-I group, suggesting that the increased expression of AQP9 had promoted HepG2 steatosis in co-cultured adipocytes. WB results showed the expression levels of p-Akt protein (0.168 ± 0.006) and p-Akt/total Akt (0.265±0.009) in HepG2-AQP9 co-culture + IGF-1 group was significantly increased (t= 16.311, 8.769,P< 0.001) than HepG2-AQP9 co-culture group, while the expression levels of AQP9 mRNA (0.327 ± 0.034) and protein (0.375 ± 0.025) was significantly decreased (t= 33.573, 9.146,P< 0.001 and 0.001). Conclusion: Adipocytes co-culture can induce steatosis in HepG2 cells, and may participate in inhibiting PI3K-Akt signaling pathway to upregulate the expression of AQP9 in steatotic HepG2 cells.


Assuntos
Adipócitos , Aquaporinas , Regulação da Expressão Gênica no Desenvolvimento , Adipócitos/citologia , Adipócitos/metabolismo , Aquaporinas/genética , Técnicas de Cocultura , Células Hep G2 , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
15.
Biochemistry (Mosc) ; 84(5): 553-561, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31234769

RESUMO

Obesity is accompanied by dyslipidemia, hypoxia, endoplasmic reticulum (ER) stress, and inflammation, representing the major risk factor for the development of insulin resistance (IR) and type 2 diabetes. We modeled these conditions in cultured 3T3-L1 adipocytes and studied their effect on insulin signaling, glucose uptake, and inflammatory response via activation of stress-dependent JNK1/2 kinases. Decreased insulin-induced phosphorylation of the insulin cascade components IRS, Akt, and AS160 was observed under all tested conditions (lipid overloading of cells by palmitate, acute inflammation induced by bacterial lipopolysaccharide, hypoxia induced by Co2+, and ER stress induced by brefeldin A). In all the cases, except the acute inflammation, glucose uptake by adipocytes was reduced, and the kinetics of JNK1/2 activation was bi-phasic exhibiting sustained activation for 24 h. By contrast, in acute inflammation, JNK1/2 phosphorylation increased transiently and returned to the basal level within 2-3 h of stimulation. These results suggest a critical role of sustained (latent) vs. transient (acute) inflammation in the induction of IR and impairment of glucose utilization by adipose tissue. The components of the inflammatory signaling can be promising targets in the development of new therapeutic approaches for preventing IR and type 2 diabetes.


Assuntos
Inflamação , Resistência à Insulina , Obesidade/patologia , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ácidos Graxos não Esterificados/farmacologia , Inflamação/etiologia , Insulina/farmacologia , Lipopolissacarídeos/farmacologia , Camundongos , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Proteína Quinase 9 Ativada por Mitógeno/metabolismo , Obesidade/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
16.
Life Sci ; 231: 116558, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31194993

RESUMO

AIMS: We aimed to explore the role of SIRT6 in Insulin resistance (IR). We are the first to investigate on this crucial relationship in an obese mouse model fed on a high-fat diet (HFD) and an IR model based on the mature 3T3-L1-derived adipocytes. MAIN METHODS: Western blotting (WB) and qPCR analysis were performed to evaluate the SIRT6 protein and mRNA expressions in HFD mice as well as IR cells. Injection of adenovirus encoding SIRT6 gene in HFD mice and transfection of pcDNA3-SIRT6 in IR cells increased the glucose uptake levels and insulin sensitivity. KEY FINDINGS: The positive regulatory effects of SIRT6 on transient receptor potential vallinoid 1 (TRPV1) in IR cells were confirmed by a mechanistic investigation at both protein and mRNA levels. Further, the overexpression of SIRT6 was found to activate the TRPV1/Calcitonin gene-related peptide (CGRP) signaling and upregulate the glucose transporter (GLUT) expression at protein and mRNA levels. Additionally, administration of the TRPV1 antagonist, SB-705498 repressed the insulin sensitivity upregulated by SIRT6 overexpression accompanied with the inhibition of CGRP and decrease in GLUT proportions. The results also showed that TRPV1 agonist, Capsaicin boosted the SIRT6-induced glucose uptake, CGRP production, and GLUT4 levels. SIGNIFICANCE: Overall, SIRT6 was concluded to be involved in the TRPV1-CGRP-GLUT4 signaling axis thus leading to increased glucose uptake and decreased IR in HFD mice and 3T3-L1 adipocytes. Therefore, in terms of obesity and diabetes, SIRT6 is a novel candidate for treating IR.


Assuntos
Glucose/metabolismo , Resistência à Insulina/fisiologia , Sirtuínas/metabolismo , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Transporte Biológico , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Transportador de Glucose Tipo 4/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Terapia de Alvo Molecular , Obesidade/metabolismo , Canais de Cátion TRPV/metabolismo
17.
Mol Biol (Mosk) ; 53(3): 497-501, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31184615

RESUMO

Homeodomain transcription factors play a significant role in adipocyte differentiation. The role of Pbx1 and Prep1, proteins of the TALE family (the three amino acid loop extension), was previously established in adipocyte differentiation of mesenchymal stromal cells and 3T3-L1 cell line. In this study, with the use of RNA interference technology we show that another transcription factor from the same family, Meis1, which is a core protein of mature cardiomyocytes, represses adipogenesis to a greater degree than its paralog Meis2. A number of Meis target genes, markers of adipocytes, are identified. This may indicate the transcriptional mechanism of the effect of Meis1 on the adipocyte differentiation of mouse preadipocytes.


Assuntos
Adipócitos/citologia , Diferenciação Celular , Proteína Meis1/metabolismo , Miócitos Cardíacos/metabolismo , Adipócitos/metabolismo , Animais , Diferenciação Celular/genética , Proteínas de Homeodomínio/metabolismo , Camundongos , Células-Tronco/citologia , Células-Tronco/metabolismo
18.
Phytother Res ; 33(7): 1888-1897, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31155812

RESUMO

Increased adiposity has been associated with adipose tissue low-grade inflammation leading to insulin resistance. Adipocyte differentiation inhibitors are expected to be effective in preventing obesity and related diseases. Anthocyanins (ACNs) are associated to enhanced adipocyte function and protection from metabolic stress. Herein, we evaluated the in vitro protective effects of an ACN rich extract against palmitic acid (PA)-induced hypertrophy, inflammation, and insulin resistance in 3T3-L1 adipocytes. ACN extract pretreatment reduces lipid accumulation and peroxisome proliferators-activated receptor-γ protein levels induced by PA. In addition, PA induces inflammation with activation of NF-κB pathway, whereas ACN extract pretreatment dose-dependently inhibited this pathway. Furthermore, adipocyte dysfunction associated with hypertrophy induces insulin resistance by affecting phosphatidylinositol 3-kinase-protein kinase B/Akt axis, GLUT-1, and adiponectin mRNA levels. ACN extract pretreatment reverts these effects induced by PA and moreover was able to induce insulin pathway with levels higher than insulin control cells, supporting an insulin sensitizer role for ACNs. This study demonstrates a prevention potential of ACNs against obesity comorbidities, due to their protective effects against inflammation/insulin resistance in adipocytes. In addition, these results contribute to the knowledge and strategies on the evaluation of the mechanism of action of ACNs from a food source under basal and insulin resistance conditions related to obesity.


Assuntos
Adipócitos/efeitos dos fármacos , Antocianinas/farmacologia , Anti-Inflamatórios/farmacologia , Resistência à Insulina , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Hipertrofia , Camundongos , Ácido Palmítico
19.
PLoS Genet ; 15(6): e1008244, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31233501

RESUMO

Berardinelli-Seip congenital generalized lipodystrophy is associated with increased bone mass suggesting that fat tissue regulates the skeleton. Because there is little mechanistic information regarding this issue, we generated "fat-free" (FF) mice completely lacking visible visceral, subcutaneous and brown fat. Due to robust osteoblastic activity, trabecular and cortical bone volume is markedly enhanced in these animals. FF mice, like Berardinelli-Seip patients, are diabetic but normalization of glucose tolerance and significant reduction in circulating insulin fails to alter their skeletal phenotype. Importantly, the skeletal phenotype of FF mice is completely rescued by transplantation of adipocyte precursors or white or brown fat depots, indicating that adipocyte derived products regulate bone mass. Confirming such is the case, transplantation of fat derived from adiponectin and leptin double knockout mice, unlike that obtained from their WT counterparts, fails to normalize FF bone. These observations suggest a paucity of leptin and adiponectin may contribute to the increased bone mass of Berardinelli-Seip patients.


Assuntos
Adiponectina/genética , Leptina/genética , Lipodistrofia Generalizada Congênita/genética , Osteosclerose/genética , Adipócitos/metabolismo , Tecido Adiposo Marrom/metabolismo , Animais , Densidade Óssea/genética , Modelos Animais de Doenças , Feminino , Glucose/genética , Glucose/metabolismo , Humanos , Insulina/genética , Gordura Intra-Abdominal/metabolismo , Lipodistrofia Generalizada Congênita/complicações , Lipodistrofia Generalizada Congênita/patologia , Camundongos , Camundongos Knockout , Osteosclerose/etiologia , Osteosclerose/metabolismo , Osteosclerose/patologia , Esqueleto/metabolismo , Esqueleto/patologia , Gordura Subcutânea/metabolismo
20.
J Physiol Pharmacol ; 70(1)2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31172970

RESUMO

Atrial fibrillation (AF) is a commonly occurring arrhythmia which significantly reduces patients' quality of life and substantially shortens life expectancy. Although long chain fatty acids (LCFAs) are the basic energy substrates for myocardial metabolism, their excess can result in lipotoxicity, which increases the risk of arrhythmia. Intracellularly, LCFAs are bound by fatty acid biding proteins (FABPs) and this results in low level of free LCFAs in the cytoplasm. Based on this principle, FABPs are considered "safeguards" against overwhelming accumulation of esterified into different bioactive lipid fractions (e.g. ceramide, diacylglycerols) LCFAs. So far, several FABPs have been discovered in humans. Currently, in relation to cardiovascular diseases heart-type fatty acid binding protein (H-FABP) and adipocyte fatty acid binding protein (A-FABP) play significant roles. Nowadays, A-FABP is of great interest for research related with obesity, diabetes and coexisting disorders including cardiovascular diseases. Concomitantly, H-FABP is already well-established marker in the early diagnosis of myocardial infarction. Moreover, FABPs were assigned as a potential biomarker of AF in patients with de novo diagnosed arrhythmia, chronic heart failure (CHF), and in patients undergoing cardiac surgery. Another group of studies where the concentrations of plasma FABPs were analyzed are patients subjected to electrical cardioversion (ECV) and radio-catheter ablation therapy (RFA). It is worth mentioning that, in addition to traditional anti-arrhythmic drugs (AADs) or ECV, ablation techniques are used with good effects. Even though the treatment of arrhythmias is constantly developing, the maintenance of the sinus rhythm (SR) is still a serious problem. Therefore, it is worth looking for a biomarker which is suitable for the patient's treatment qualifications as well as assessing its effectiveness. Thus, the aim of this work is to present current data on the clinical significance of FABPs in terms of the development and treatment of AF.


Assuntos
Fibrilação Atrial/sangue , Proteínas de Ligação a Ácido Graxo/metabolismo , Adipócitos/metabolismo , Animais , Antiarrítmicos/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Biomarcadores/sangue , Ablação por Cateter , Cardioversão Elétrica , Insuficiência Cardíaca/sangue , Humanos , Miocárdio/metabolismo
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