RESUMO
BACKGROUND: Recent studies suggest that Embelin, a natural plant extract might have the potential to prevent body weight gain in rats. However, the mechanisms involved remain to be elucidated. METHODS: Effects of Embelin on adipocyte differentiation and lipogenesis were studied in murine ST2 stromal cells and C3H10T1/2 mesenchymal cells. The mechanisms through which Embelin regulates adipogenic differentiation and lipogenesis were explored. The in vivo anti-obesity effects of Embelin in high-fat diet (HFD)-induced obesity mice and possible transcriptional impact were investigated. RESULTS: Embelin treatment suppressed ST2 and C3H10T1/2 cells to proliferate, and differentiate into mature adipocytes, along with the inhibition of adipogenic factors peroxisome proliferator-activated receptor γ, CCAAT/enhancer binding protein-α, adipocyte protein 2 and adipsin. Embelin treatment also decreased the expression levels of lipogenic factors sterol regulatory element-binding protein 1, fatty acid synthase, acetyl-CoA carboxylase 1 and stearoyl-Coenzyme A desaturase 1. Embelin promoted the translocation of ß-catenin from the cytoplasm into the nucleus in C3H10T1/2. The nuclear protein levels of ß-catenin and TCF-4 were increased following Embelin treatment. Furthermore, Dickkopf-1 (Dkk1) expression was downregulated by Embelin, and overexpression of Dkk1 in C3H10T1/2 reversed the inhibition of adipogenesis and lipogenesis by Embelin. In vivo studies showed that Embelin treatment reduced the gain of body weight and fat, decreased the serum level of triglycerides, free fatty acid and total cholesterol, and improved glucose tolerance and insulin resistance in HFD-fed mice. Moreover, Embelin blocked induction of adipogenic and lipogenic factors and Dkk1 in adipose tissue in HFD-fed mice. CONCLUSIONS: The present work provides evidences that Embelin is effective in inhibiting adipogenesis and lipogenesis in vitro and the mechanisms may involve canonical Wnt signaling. Embelin has the potential to prevent body weight gain and fat accumulation, and to improve obesity-related glucose tolerance impairment and insulin resistance in the HFD-fed mice.
Assuntos
Adipogenia/efeitos dos fármacos , Fármacos Antiobesidade/farmacologia , Benzoquinonas/farmacologia , Dieta Hiperlipídica/efeitos adversos , Lipogênese/efeitos dos fármacos , Obesidade/prevenção & controle , Via de Sinalização Wnt/efeitos dos fármacos , Células 3T3-L1/fisiologia , Adipócitos/efeitos dos fármacos , Adipócitos/fisiologia , Adipogenia/fisiologia , Animais , Western Blotting , Modelos Animais de Doenças , Lipogênese/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/tratamento farmacológico , PPAR gama/metabolismo , Extratos Vegetais/farmacologia , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Aumento de Peso/efeitos dos fármacosRESUMO
BACKGROUND: From ancient times, marine algae have emerged as alternative medicine and foods, contains the rich source of natural products like proteins, vitamins, and secondary metabolites, especially Chlorella vulgaris (C. vulgaris) contains numerous anti-inflammatory, antioxidants and wound healing substances. Type 2 diabetes mellitus is closely associated with adipogenesis and their factors. Hence, we aimed to investigate the chemical constituents and adipogenic modulatory properties of C. vulgaris in 3T3-L1 pre-adipocytes. RESULTS: We analysed chemical constituents in ethanolic extract of C. vulgaris (EECV) by LC-MS. Results revealed that the EECV contains few triterpenoids and saponin compounds. Further, the effect of EECV on lipid accumulation along with genes and proteins expressions which are associated with adipogenesis and lipogenesis were evaluated using oil red O staining, qPCR and western blot techniques. The data indicated that that EECV treatment increased differentiation and lipid accumulation in 3T3-L1 cells, which indicates positive regulation of adipogenic and lipogenic activity. These increases were associated with up-regulation of PPAR-γ2, C/EBP-α, adiponectin, FAS, and leptin mRNA and protein expressions. Also, EECV treatments increased the concentration of glycerol releases as compared with control cells. Troglitazone is a PPAR-γ agonist that stimulates the PPAR-γ2, adiponectin, and GLUT-4 expressions. Similarly, EECV treatments significantly upregulated PPAR-γ2, adiponectin, GLUT-4 expressions and glucose utilization. Further, EECV treatment decreased AMPK-α expression as compared with control and metformin treated cells. CONCLUSION: The present research findings confirmed that the EECV effectively modulates the lipid accumulation and differentiation in 3T3-L1 cells through AMPK-α mediated signalling pathway.
Assuntos
Células 3T3-L1/efeitos dos fármacos , Chlorella vulgaris/química , Extratos Vegetais/farmacologia , Alga Marinha/química , Células 3T3-L1/fisiologia , Proteínas Quinases Ativadas por AMP/análise , Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adiponectina/análise , Adiponectina/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Diabetes Mellitus Tipo 2/metabolismo , Regulação para Baixo , Expressão Gênica , Glucose/metabolismo , Transportador de Glucose Tipo 4/análise , Transportador de Glucose Tipo 4/efeitos dos fármacos , Transportador de Glucose Tipo 4/metabolismo , Camundongos , PPAR gama/análise , PPAR gama/efeitos dos fármacos , PPAR gama/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Regulação para CimaRESUMO
BACKGROUND: From ancient times, marine algae have emerged as alternative medicine and foods, contains the rich source of natural products like proteins, vitamins, and secondary metabolites, especially Chlorella vulgaris (C. vulgaris) contains numerous anti-inflammatory, antioxidants and wound healing substances. Type 2 diabetes mellitus is closely associated with adipogenesis and their factors. Hence, we aimed to investigate the chemical constituents and adipo-genic modulatory properties of C. vulgaris in 3T3-L1 pre-adipocytes. RESULTS: We analysed chemical constituents in ethanolic extract of C. vulgaris (EECV) by LC-MS. Results revealed that the EECV contains few triterpenoids and saponin compounds. Further, the effect of EECV on lipid accumulation along with genes and proteins expressions which are associated with adipogenesis and lipogenesis were evaluated using oil red O staining, qPCR and western blot techniques. The data indicated that that EECV treatment increased differentiation and lipid accumulation in 3T3-L1 cells, which indicates positive regulation of adipogenic and lipogenic activity. These increases were associated with up-regulation of PPAR-γ2, C/EBP-α, adiponectin, FAS, and leptin mRNA and protein expressions. Also, EECV treatments increased the concentration of glycerol releases as compared with control cells. Troglitazone is a PPAR-γ agonist that stimulates the PPAR-y2, adiponectin, and GLUT-4 expressions. Similarly, EECV treatments significantly upregulated PPAR-γ, adiponectin, GLUT-4 expressions and glucose utilization. Further, EECV treatment decreased AMPK-α expression as compared with control and metformin treated cells. CONCLUSION: The present research findings confirmed that the EECV effectively modulates the lipid accumulation and differentiation in 3T3-L1 cells through AMPK-α mediated signalling pathway.
Assuntos
Animais , Camundongos , Alga Marinha/química , Extratos Vegetais/farmacologia , Células 3T3-L1/efeitos dos fármacos , Chlorella vulgaris/química , Fatores de Tempo , Regulação para Baixo , Expressão Gênica , Diferenciação Celular/efeitos dos fármacos , Regulação para Cima , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células 3T3-L1/fisiologia , PPAR gama/análise , PPAR gama/efeitos dos fármacos , PPAR gama/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Adiponectina/análise , Adiponectina/metabolismo , Transportador de Glucose Tipo 4/análise , Transportador de Glucose Tipo 4/efeitos dos fármacos , Transportador de Glucose Tipo 4/metabolismo , Proteínas Quinases Ativadas por AMP/análise , Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Glucose/metabolismoRESUMO
AIMS: Obesity develops when energy intake chronically exceeds total energy expenditure. We sought to assess whether the flavonoid-rich fraction of crude extracts from Daphne genkwa Siebold et Zuccarini (GFF) might inhibit adipogenesis of 3T3-L1 cells. MAIN METHODS: Cell viability of 3T3-L1 preadipocytes was assessed by MTT assays, and lipid accumulation was measured by Oil Red O. Adipogenesis related factors were checked by Western blot analysis. Flow cytometry was used to analyze the mitotic cell cycle during the mitotic clonal expansion phase. KEY FINDINGS: Among five flavonoids isolated from GFF, only apigenin potently inhibited the differentiation of 3T3-L1 cells. Apigenin reduced CCAAT/enhancer binding protein (C/EBP) α and peroxisome proliferator-activated receptor γ levels. Apigenin-treated 3T3-L1 cells failed to undergo clonal expansion during the early phase of adipocyte differentiation. Apigenin arrested cell cycle progression at the G0/G1 phase. This effect was associated with a marked decrease in cyclin D1 and cyclin-dependent kinase 4 expression, with the concomitant and sustained expression of p27(Kip1). In addition, apigenin inhibited the DNA-binding activity of C/EBPß in differentiating 3T3-L1 cells by down-regulating the 35kDa isoform of C/EBPß (liver-enriched activating protein) and up-regulating the expression of two different sets of C/EBP inhibitors: C/EBP homologous protein and the phospho-liver-enriched inhibitory protein isoform of C/EBPß. SIGNIFICANCE: These findings suggest that apigenin can prevent 3T3-L1 preadipocyte differentiation by the inhibition of the mitotic clonal expansion and the adipogenesis related factors and upregulation of the expression of multiple C/EBPß inhibitors.
Assuntos
Células 3T3-L1/efeitos dos fármacos , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Apigenina/farmacologia , Daphne/química , Células 3T3-L1/metabolismo , Células 3T3-L1/fisiologia , Adipogenia/fisiologia , Animais , Apigenina/isolamento & purificação , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ciclina D1/metabolismo , Quinase 4 Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Camundongos , PPAR gama/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologiaRESUMO
Echinacea purpurea has been shown to have anti-diabetic activities; for example, it activates peroxisome proliferator-activated receptor γ (PPARγ) and increases insulin-stimulated glucose uptake. Adipogenesis has been used to study the insulin signaling pathway and to screen anti-diabetic compounds. The present study was conducted to investigate the effects of an ethanol extract of E. purpurea (EEEP) and its constituents on the insulin-induced adipocyte differentiation of 3T3-L1 preadipocytes. When adipocyte differentiation was induced with insulin plus 3-isobutyl-1-methylxanthine and dexamethasone, the accumulation of lipid droplets and the cellular triglyceride content were significantly increased by EEEP. The expressions of PPARγ and C/EBPα in adipocytes treated with EEEP were gradually increased as compared with control cells. Fat accumulation and triglyceride content of adipocytes treated with dodeca-2(E),4(E)-dienoic acid isobutylamide were significantly increased as compared with control cells. The expressions of PPARγ and C/EBPα in adipocytes treated with dodeca-2(E),4(E)-dienoic acid isobutylamide were significantly higher than in control cells. These results suggest EEEP promotes the adipogenesis that is partially induced by insulin and that dodeca-2(E),4(E)-dienoic acid isobutylamide appears to be responsible for EEEP-enhanced adipocyte differentiation.