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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.
Chem Biodivers ; 16(10): e1900347, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31532890

RESUMO

Catechins in green tea are well-known to be effective in reducing the risk of obesity. The purpose of this study was to elucidate the effects of catechins present in green tea on adipocyte differentiation and mature adipocyte metabolism. Treatment of 3T3-L1 mouse adipocyte during differentiation adipocytes with (-)-epigallocatechin (EGC) and gallic acid (GA) resulted in dose-dependent inhibition of adipogenesis. Specifically, EGC increased adiponectin and uncoupling protein 1 (UCP1) transcription in mature adipocytes. Transcription levels of adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) were not significantly impacted by either of the compounds. These results suggest that the EGC is the most effective catechin having anti-obesity activity. Finally, EGC is an attractive candidate component for remodeling obesity.


Assuntos
Tecido Adiposo Marrom/efeitos dos fármacos , Fármacos Antiobesidade/farmacologia , Catequina/análogos & derivados , Células 3T3-L1 , Tecido Adiposo Marrom/metabolismo , Animais , Fármacos Antiobesidade/química , Fármacos Antiobesidade/isolamento & purificação , Catequina/química , Catequina/isolamento & purificação , Catequina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Camundongos , Estrutura Molecular , Relação Estrutura-Atividade , Chá/química
4.
Life Sci ; 232: 116683, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31344430

RESUMO

AIMS: Previous work has demonstrated that ketogenic diets promote white fat browning; however, the exact mechanisms underlying this phenomenom have yet to be elucidated. Recently, an in vitro study showed that supraphysiological concentrations of ß-hydroxybutyrate (ßHB) had a strong influence on the induction of adipocyte browning. On the other hand, concentrations in the physiological range, achieved through ketogenic diets and prolonged fasting produce values of 1-3 mM and 4-7 mM, respectively. Herein, we investigated the impact of physiological concentrations of ßHB on metabolism, and the expression of uncoupling protein 1 (UCP1) and other browning markers in adipose tissues. MAIN METHODS: The effects of ßHB on adipocyte browning were investigated in vitro, using primary cultures of isolated visceral and subcutaneous fat cells and cultured 3T3-L1 adipocytes, and in vivo. KEY FINDINGS: It was determined that ßHB failed to induce changes in the oxidative capacity, citrate synthase activity or browning gene expression patterns in isolated adipocytes, and did not exert a permissive effect on ß-adrenergic agonist-induced browning. In addition, 3T3-L1 adipocytes differentiated following ßHB treatment exhibited downregulated Ucp1 expression levels, a result that was recapitulated in the subcutaneous adipose tissue of Wistar rats after ßHB salt treatment. Rats administered ßHB salts also presented reduced brown adipose tissue UCP1 protein expression. SIGNIFICANCE: The mechanisms underlying ketogenic diet-induced browning of adipocytes are not known. The results from the present study indicate that physiological concentrations of ßHB are not responsible for this phenomenon, despite the observed ßHB-mediated downregulation of UCP1 expression.


Assuntos
Ácido 3-Hidroxibutírico/metabolismo , Tecido Adiposo Marrom/metabolismo , Células 3T3-L1 , Animais , Masculino , Camundongos , Ratos , Ratos Wistar , Proteína Desacopladora 1/metabolismo
5.
Chem Biol Interact ; 311: 108755, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31319077

RESUMO

Effective control of white adipose tissue accumulation would provide a therapeutic strategy for obesity, which poses a growing global problem. The plant chemical mangiferin stimulates adenosine monophosphate-activated protein kinase (AMPK), which inhibits adipogenesis and has therefore been considered a therapeutic target for obesity and related diseases. We previously reported the anti-inflammatory properties of 6'-O-acetyl mangiferin (OAM). In this study, we evaluated the potential of OAM as an AMPK activator in vitro in 3T3-L1 preadipocytes. OAM inhibited adipogenesis as indicated by lower intracellular lipid and triglyceride accumulation as well as reduced adipogenic gene and protein expression upon treatment. OAM-treated 3T3-L1 cells excreted more glycerol, indicating increased lipolysis, which was supported by increased expression of lipolysis-related genes, including adipose triglyceride lipase and hormone-sensitive lipase. We determined that OAM upregulates lipolysis via phosphorylation-dependent activation of AMPK. Further, OAM upregulated the ß-oxidation pathway as indicated by enhanced expression of phosphorylated acetyl-CoA-carboxylase and long-chain acyl-CoA synthetase 1. In conclusion, OAM markedly decreased intracellular lipid accumulation by enhancing lipolysis via AMPK activation and by upregulating ß-oxidation. Thus, OAM has potential as a drug for the prevention and/or improvement of obesity and related diseases and deserves further study.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Adipogenia/efeitos dos fármacos , Iris (Planta)/química , Lipólise/efeitos dos fármacos , Xantonas/farmacologia , Células 3T3-L1 , Proteínas Quinases Ativadas por AMP/genética , Acetil-CoA Carboxilase/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Iris (Planta)/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , PPAR gama/genética , PPAR gama/metabolismo , Fosforilação/efeitos dos fármacos , Triglicerídeos/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.
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
8.
Biochim Biophys Acta Gene Regul Mech ; 1862(8): 796-806, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31295563

RESUMO

N6-methyladenosine (m6A), the most abundant internal mRNA modification in eukaryotes, plays a vital role in regulating adipogenesis. However, its underlying mechanism remains largely unknown. Here, we reveal that deletion of m6A demethylase FTO in porcine and mouse preadipocytes inhibits adipogenesis through JAK2-STAT3-C/EBPß signaling. Mechanistically, FTO deficiency suppresses JAK2 expression and STAT3 phosphorylation, leading to attenuated transcription of C/EBPß, which is essential for the early stage of adipocyte differentiation. Using dual-luciferase assay, we validate that knockdown of FTO reduces expression of JAK2 in an m6A-dependent manner. Furthermore, we find that m6A "reader" protein YTHDF2 directly targets m6A-modified transcripts of JAK2 and accelerates mRNA decay, which results in decreased JAK2 expression and inactivated JAK2-STAT3-C/EBPß signaling, thereby inhibiting adipogenesis. Collectively, our results provide a novel insight into the molecular mechanism of m6A methylation in post-transcriptional regulation of JAK2-STAT3-C/EBPß signaling axis and highlight the crucial role of m6A modification and its modulators in adipogenesis.


Assuntos
Adenosina/análogos & derivados , Adipogenia , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Janus Quinase 2/genética , Fator de Transcrição STAT3/metabolismo , Células 3T3-L1 , Adenosina/metabolismo , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Animais , Diferenciação Celular , Deleção de Genes , Regulação da Expressão Gênica , Camundongos , Fosforilação , Estabilidade de RNA , Proteínas de Ligação a RNA , Transdução de Sinais , Suínos
9.
J Agric Food Chem ; 67(30): 8361-8369, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31339708

RESUMO

The calcium-sensing receptor (CaSR), a G-protein receptor, is well recognized for its role in the regulation of adipocyte proliferation, in modulating adipose tissue dysfunction, and as a potential target for therapeutic intervention. In the present study, we investigate the anti-inflammatory effect of γ-glutamylvaline (γ-EV) on mouse adipocytes and explore the role of γ-EV-activated CaSR in the regulation of cellular homeostasis using the mouse 3T3-L1 cell line in vitro model. Our results indicate that the 3T3-L1 adipocyte-like cells accumulated lipids and expressed CaSR after 2 days of differentiation and 7 days of maturation period. The pretreatment with γ-EV (10 µM) suppressed the production of TNF-α-induced pro-inflammatory cytokines, i.e., IL-6 (23.92 ± 5.45 ng/mL, p < 0.05)) and MCP-1 (101.17 ± 39.93 ng/mL, p < 0.05), while enhancing the expression of PPARγ (1.249 ± 0.109, p < 0.001) and adiponectin (7.37 ± 0.59 ng/mL, p < 0.05). Elevated expression of Wnt5a was detected in γ-EV-treated cells (115.90 ± 45.50, p < 0.001), suggesting the involvement of the Wnt/ß-catenin pathway. Also, phosphorylation of ß-catenin was shown to be significantly inhibited (0.442 ± 0.034) by TNF-α but restored when cells were pretreated with γ-EV (0.765 ± 0.048, p < 0.05). These findings suggest that γ-EV-induced CaSR activation not only prevents TNF-α-induced inflammation in adipocytes but also modulates the cross-talk between Wnt and PPARγ pathways. Concentrations of serine phosphorylated IRS-1 were shown to be lower in γ-EV-treated cells, indicating γ-EV may also prevent inflammation in the context of insulin resistance. Thus, γ-EV-activated CaSR plays a significant role in the cross-talk between adipocyte inflammatory and metabolic pathways through the regulation of extracellular sensing.


Assuntos
Adipócitos/efeitos dos fármacos , Dipeptídeos/farmacologia , Receptores de Detecção de Cálcio/imunologia , Células 3T3-L1 , Adipócitos/imunologia , Animais , Interleucina-6/genética , Interleucina-6/imunologia , Camundongos , PPAR gama/genética , PPAR gama/imunologia , Fosforilação , Receptores de Detecção de Cálcio/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
10.
Life Sci ; 233: 116682, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31348945

RESUMO

AIMS: Fibrosis as the hallmark of adipose tissue dysfunction which is associated with insulin resistance and type 2 diabetes, results from deposition of excess extra cellular matrix components like collagen and increased cell death. Here we investigated the effect of antidiabetic drug, Metformin, on the factors that play role in fibrosis such as; integrin/ERK pathway, collagen VI, MMP2, MMP9, apoptosis markers including DAPK1, DAPK3, DAP, SIVA, necrosis markers including RIPK1, RIPK3, and MLKL in insulin resistant and hypertrophied adipocytes. METHODS: 3T3-L1 adipocytes after differentiation to insulin resistant and hypertrophied cells, treated with Metformin, and the gene expression of aforementioned factors assayed by real time PCR. The protein expression of collagen VI and ERK assayed by western blotting. KEY FINDINGS: The expression of integrins changed from 0.5 to 6-fold in hypertrophied adipocyte versus adipocyte. Apoptosis and necrosis markers increased >1.5-fold in insulin resistant and hypertrophied adipocytes. Also ECM components and ERK activation increased >2-fold and 1.5-fold, respectively in insulin resistant and hypertrophied adipocytes. Metformin caused reduction of activity of integrin/ERK pathway in Metformin treated insulin resistant and hypertrophied adipocytes compared to untreated group. Metformin also reduced collagen VI in both gene and protein expression level, MMP2 and MMP9 in gene expression, and also the expression of apoptosis and necrosis gene. SIGNIFICANCE: Metformin with reduction of ECM component as collagen VI, MMP2 and MMP9, integrin/ERK pathway, necrosis markers as RIPK1, RIPK3 and MLKL, and apoptosis markers including DAP, DAPK1, DAPK3 and SIVA effects on fibrosis in insulin resistant and hypertrophied adipocytes in vitro.


Assuntos
Adipócitos/efeitos dos fármacos , Fibrose/prevenção & controle , Regulação da Expressão Gênica/efeitos dos fármacos , Hipertrofia/prevenção & controle , Hipoglicemiantes/farmacologia , Resistência à Insulina , Metformina/farmacologia , Células 3T3-L1 , Animais , Apoptose , Diferenciação Celular , Colágeno Tipo IV/genética , Colágeno Tipo IV/metabolismo , Matriz Extracelular/efeitos dos fármacos , Integrinas/genética , Integrinas/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Necrose
11.
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
12.
Food Chem Toxicol ; 131: 110576, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31199990

RESUMO

Ivermectin, a member of the avermectins, is one of the most used anti-parasitic agents, and acts by binding to glutamate-gated chloride channels in invertebrate nerve cells. There is limited information, however, on the effects of ivermectin in non-neural cell, such as adipocytes. The present work aimed to investigate the role of ivermectin in adipogenesis using 3T3-L1 preadipocytes. Ivermectin inhibited the differentiation of preadipocytes and triglyceride (TG) accumulation. In particular, the treatment of ivermectin at the middle to late adipogenic differentiation period (day 2-8) was correlated with the inhibition of fat accumulation. Ivermectin treatment also significantly modulated the mRNA expression of key markers in adipogenesis, fatty acid synthesis, uptake, and oxidation, and enhanced the gene expression of two subunits of the glycine receptor (GlyR). Specifically, the protein levels of peroxisome proliferator-activated receptor gamma (PPARγ), CCAAT/enhancer-binding protein alpha (C/EBPα), and acetyl-CoA carboxylase (ACC) were reduced. Interestingly, the suppression of TG accumulation by ivermectin was partially abolished by rosiglitazone, a specific PPARγ agonist, but Z-guggulsterone, a selective FXR antagonist, failed to rescue the ivermectin-induced effect on adipogenesis. Lastly, ivermectin prevented adipogenesis induced by permethrin and fipronil. In conclusion, ivermectin inhibits adipogenesis of 3T3-L1 preadipocytes partially via PPARγ & GlyR-dependent, but not FXR-dependent, pathway.


Assuntos
Adipogenia/efeitos dos fármacos , Antiparasitários/farmacologia , Ivermectina/farmacologia , Triglicerídeos/metabolismo , Células 3T3-L1 , Animais , Diferenciação Celular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Camundongos , PPAR gama/metabolismo , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores da Glicina/metabolismo
13.
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
14.
Food Chem Toxicol ; 131: 110543, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31154084

RESUMO

A dual role of hydrogen sulfide (H2S) in inflammation is well-reported and recent studies demonstrated adipogenic effects of H2S in 3T3-L1 cells. Here, we aimed to investigate the effects of H2S on adipocyte differentiation and inflammation. H2S concentration in 3T3-L1 culture media was increased during adipocyte differentiation in parallel to adipogenic and Cth gene expression, and its inhibition using DL-Propargyl Glycine (PPG) impaired 3T3-L1 differentiation. GYY4137 and Na2S administration only in the first or in the last stage of adipocyte differentiation resulted in a significant increased expression of adipogenic genes. However, when GYY4137 or Na2S were administrated during all process no significant effects on adipogenic gene expression were found, suggesting that excessive H2S administration might exert negative effects on adipogenesis. In fact, continuous addition of Na2S, which resulted in Na2S excess, inhibited adipogenesis, whereas time-expired Na2S had no effect. In inflammatory conditions, GYY4137, but not Na2S, administration attenuated the negative effects of inflammation on adipogenesis and insulin signaling-related gene expression during adipocyte differentiation. In inflamed adipocytes, Na2S administration enhanced the negative effects of inflammatory process. Altogether these data showed that slow-releasing H2S improved adipocyte differentiation in inflammatory conditions, and that H2S proadipogenic effects depend on dose, donor and exposure time.


Assuntos
Adipócitos/efeitos dos fármacos , Sulfeto de Hidrogênio/metabolismo , Morfolinas/farmacologia , Compostos Organotiofosforados/farmacologia , Sulfetos/farmacologia , Células 3T3-L1 , Adipogenia/efeitos dos fármacos , Adipogenia/fisiologia , Alquinos/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Glicina/análogos & derivados , Glicina/farmacologia , Inflamação/fisiopatologia , Camundongos
15.
J Agric Food Chem ; 67(26): 7348-7364, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31180673

RESUMO

A chemical study on the peels of the cultivated edible mushroom Wolfiporia cocos led to the isolation and identification of 47 lanostane triterpenoids including 16 new compounds (1-16). The structures of the new compounds were determined by analysis of the NMR, MS, and electronic circular dichroism (ECD) data. Compounds 1 and 2 represent new members of the family of 4,5-secolanostane triterpenes. Compound 3 is a new aromatic lanostane triterpene with an unusual methyl rearrangement from C-10 to C-6. The absolute configurations of 1 and 8 were assigned by ECD spectra calculation. All compounds were evaluated for cytotoxicity (K562, SW480, and HepG2) and glucose-uptake-stimulating effects. Compounds 23, 25, 29, and 31 showed weak inhibition on the K562 cells with IC50 in the range of 25.7 to 68.2 µM, respectively. Compounds 21, 28, and 30 increased the glucose uptake in 3T3-L1 cells by 25%, 14%, and 50% at 5 µM, respectively. In addition, compounds 14, 23, 29, 35, and 43 showed insulin-sensitizing activity by increasing the insulin-stimulated glucose uptake at 2.5 µM in 3T3-L1 adipocytes. A preliminary structure-activity relationship analysis indicates that the 6/6/6/5 ring skeleton and the double bond between C-8 and C-9 are beneficial for the glucose-uptake-stimulating and insulin-sensitizing activities. Furthermore, the alkaline-insoluble fraction mainly containing compounds 22, 24, 28, and 31 were confirmed to have hypoglycemic and hypolipidemic activity on high-fat-diet-induced obese mice. This work confirms the potential of the peels' extracts of W. cocos as a functional food or dietary supplements.


Assuntos
Glucose/metabolismo , Extratos Vegetais/farmacologia , Triterpenos/farmacologia , Wolfiporia/química , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Camundongos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Triterpenos/química , Triterpenos/isolamento & purificação
16.
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
17.
Gene ; 710: 406-414, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31200087

RESUMO

Integrins are cell attachment receptors that function in the communication between the intracellular and extracellular compartments. Integrins and extra cellular matrix (ECM) collaborate to regulate gene expression by extracellular signal-regulated kinases (ERKs). Integrins as regulators, have critical role in ECM remodeling. Fibrosis is the hallmark of obesity and insulin resistance originated by aberrant ECM remodeling. Therefore deciphering integrins' expression profile in cells at different conditions is worthy. The aim of this study is evaluation of integrins' gene expression profile changes in mouse 3T3-L1 preadipocytes, adipocytes, insulin resistant and hypertrophic adipocytes. For this purpose, we differentiated mouse 3T3-L1 preadipocytes to adipocytes, insulin resistant and hypertrophied adipocytes and assayed integrins' gene expression in four conditions by real time-PCR. Also the proteins expression changes of ERK and collagen VI assayed by Western blotting. Data analysis has shown that integrins' gene expression changes throughout adipocyte differentiation and pathological processes. The expressions of many integrins genes were significantly up- or down-regulated by >1.5-fold during differentiation, insulin resistant, and hypertrophic adipocytes. In addition to changes in the type of integrin, the integrins expression levels were different. Integrins, on the whole were more expressed in pathological processes relative to normal adipocytes. Also, phosphorylation of ERK 1,2 was increased >1.5-fold in differentiated, insulin resistant and hypertrophied adipocytes versus preadipocytes. Collagen VI only increased 2-fold in hypertrophied adipocytes. Examination of the total integrin gene family expression during adipocyte differentiation and pathological processes, leads to the identification of differential integrin gene expression. These results suggest that the type of integrin may not only play a role in adipocyte differentiation but also in pathological processes which may associate to increased ERK pathway activity in these conditions.


Assuntos
Adipócitos/citologia , Adipócitos/patologia , Perfilação da Expressão Gênica/métodos , Integrinas/genética , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Diferenciação Celular , Colágeno Tipo VII/metabolismo , Regulação da Expressão Gênica , Hipertrofia , Resistência à Insulina , Sistema de Sinalização das MAP Quinases , Camundongos , Família Multigênica , Fosforilação
18.
Gene ; 707: 93-99, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31048067

RESUMO

The formation of bovine adipose tissue involves complex developmental and physiological processes that play a vital role in determining the quality of beef; however, the regulatory mechanisms are largely unknown. Angiopoietin-like protein 8 (ANGPTL8) has been reported to be involved in the development of adipose tissue; however, the mechanism of adipogenesis which is regulated by ANGPTL8 has not been revealed in cattle. In this study, RT-qPCR and Oil Red O staining were performed to detect the expression of ANGPTL8 and adipocyte differentiation in bovine. We found that ANGPTL8 had a high expression level in adipose tissue and that the expression pattern was consistent with those of PPARγ, C/EBPα and LPL which are key regulators and transcription factors involved in preadipocyte differentiation and adipogenesis. The overexpression of ANGPTL8 by the adenovirus vector promoted lipid droplet formation in adipocytes. Thus, we speculated that ANGPTL8 could significantly enhance lipid deposition. Moreover, the expression of LPL and SREBP1, key genes inhibiting adipogenesis, was significantly decreased by ANGPTL8 overexpression. These results suggested that ANGPTL8 promotes adipocyte differentiation. In conclusion, we consider that ANGPTL8 regulates adipocyte differentiation and adipogenesis in bovine.


Assuntos
Adipócitos/citologia , Adipogenia , Proteínas Semelhantes a Angiopoietina/genética , Proteínas Semelhantes a Angiopoietina/metabolismo , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Bovinos , Diferenciação Celular , Células Cultivadas , Regulação da Expressão Gênica , Gotículas Lipídicas/metabolismo , Camundongos , Regulação para Cima
19.
Biosci Biotechnol Biochem ; 83(9): 1782-1789, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31045477

RESUMO

Activation of the adipose lipolytic pathway during lipid metabolism is mediated by protein kinase A (PKA), which responds to ß-adrenergic stimulation, leading to increased lipolysis. Soy is well known as a functional food and it is able to affect lipolysis in adipocytes. However, the mechanism by which soy components contribute to the lipolytic pathway remains to be fully elucidated. Here, we show that hydrolyzed soy enhances isoproterenol-stimulated lipolysis and activation of PKA in 3T3-L1 adipocytes. We also found that the expression of ß-adrenergic receptors, which coordinate the activation of PKA, is elevated in adipocytes differentiated in the presence of soy hydrolysate. The activity of the soy hydrolysate towards ß-adrenergic receptor expression was detected in its hydrophilic fraction. Our results suggest that the soy hydrolysate enhances the PKA pathway through the upregulation of ß-adrenergic receptor expression and thereby, increase lipolysis in adipocytes.


Assuntos
Adipócitos/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Isoproterenol/farmacologia , Lipólise/efeitos dos fármacos , Receptores Adrenérgicos beta/metabolismo , Soja/metabolismo , Células 3T3-L1 , Animais , Cromatografia Líquida de Alta Pressão/métodos , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Hidrólise , Camundongos
20.
Molecules ; 24(9)2019 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-31035366

RESUMO

Limonoids are phytochemicals with a variety of biological properties. In the present study, we elucidated the molecular mechanism of suppression of adipogenesis in adipocytes by a limonoid, 7-deacetoxy-7-oxogedunin (CG-1) from Carapa guianensis (Meliaceae), known as andiroba. CG-1 reduced the accumulation of intracellular triglycerides in a concentration-dependent manner. The expression levels of the adipogenic, lipogenic, and lipolytic genes were decreased by CG-1 treatment, whereas the glycerol release level was not affected. When CG-1 was added into the medium during days 0-2 of 6-days-adipogenesis, the accumulation of intracellular lipids and the mRNA levels of the adipogenesis-related genes were decreased. In addition, the phosphorylation level of insulin receptor substrate-1 (IRS-1) and Akt in the early phase of adipocyte differentiation (within 1 day after initiating adipocyte differentiation) was reduced by CG-1. Furthermore, insulin-activated translocation of glucose transporter 4 to the plasma membranes in adipocytes was suppressed by CG-1, followed by decreased glucose uptake into the cells. These results indicate that an andiroba limonoid CG-1 suppressed the accumulation of intracellular lipids in the early phase of adipocyte differentiation through repression of IRS-1/Akt-mediated glucose uptake in adipocytes.


Assuntos
Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Transportador de Glucose Tipo 4/genética , Glucose/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo , Limoninas/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células 3T3-L1 , Adipogenia/efeitos dos fármacos , Animais , Transportador de Glucose Tipo 4/metabolismo , Limoninas/química , Meliaceae/química , Camundongos , Estrutura Molecular
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