RESUMEN
SCOPE: Indole-3-carbinol (I3C), a derivative abundant in cruciferous vegetables such as cabbage, is well known for its various health benefits such as chemo-preventive and anti-obesity effects. I3C is easily metabolized to 3,3'-diindolylmethane (DIM), a more stable form, in acidic conditions of the stomach. However, the anti-obesity effect of DIM has not been investigated clearly. We sought to investigate the effect of DIM on diet-induced obesity and to elucidate its underlying mechanisms. METHODS AND RESULTS: High-fat diet (HFD)-fed obese mouse and MDI-induced 3T3-L1 adipogenesis models were used to study the effect of DIM. We observed that the administration of DIM (50 mg/kg BW) significantly suppressed HFD-induced obesity, associated with a decrease in adipose tissue. Additionally, we observed that DIM treatment (40 and 60 µM), but not I3C treatment, significantly inhibited MDI-induced adipogenesis by reducing the levels of several adipogenic proteins such as PPAR-γ and C/EBPα. DIM, but not I3C, suppressed cell cycle progression in the G1 phase, which occurred in the early stage of adipogenesis, inducing post-translational degradation of cyclin D1 by inhibiting ubiquitin specific peptidase 2 (USP2) activities. CONCLUSION: Our findings indicate that cruciferous vegetables, which can produce DIM as a metabolite, have the potential to prevent or treat chronic obesity.
Asunto(s)
Adipogénesis/efectos de los fármacos , Indoles/farmacología , Obesidad/tratamiento farmacológico , Proteasas Ubiquitina-Específicas/genética , Células 3T3-L1 , Adipocitos/efectos de los fármacos , Animales , Proteínas Potenciadoras de Unión a CCAAT/genética , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Diferenciación Celular/efectos de los fármacos , Ciclina D1/genética , Ciclina D1/metabolismo , Dieta Alta en Grasa , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , PPAR gamma/genética , PPAR gamma/metabolismo , Ubiquitina Tiolesterasa , Proteasas Ubiquitina-Específicas/antagonistas & inhibidores , Proteasas Ubiquitina-Específicas/metabolismoRESUMEN
In the present study, we aimed to investigate the antiobesity effect of CAPE in vivo, and the mechanism by which CAPE regulates body weight in vitro. To confirm the antiobesity effect of CAPE in vivo, mice were fed with a high fat diet (HFD) with different concentrations of CAPE for 5 weeks. CAPE significantly reduced body weight gain and epididymal fat mass in obese mice fed a HFD. In accordance with in vivo results, Oil red O staining results showed that CAPE significantly suppressed MDI-induced adipogenesis of 3T3-L1 preadipocytes. FACS analysis results showed that CAPE delayed MDI-stimulated cell cycle progression, thereby contributing to inhibit mitotic clonal expansion (MCE), which is a prerequisite step for adipogenesis. Also, CAPE regulated the expression of cyclin D1 and the phosphorylation of ERK and Akt, which are upstream of cyclin D1. These results suggest that CAPE exerts an antiobesity effect in vivo, presumably through inhibiting adipogenesis at an early stage of adipogenesis.
Asunto(s)
Adipogénesis/efectos de los fármacos , Fármacos Antiobesidad/administración & dosificación , Ácidos Cafeicos/administración & dosificación , Mitosis/efectos de los fármacos , Obesidad/tratamiento farmacológico , Obesidad/fisiopatología , Alcohol Feniletílico/análogos & derivados , Própolis/química , Adipocitos/citología , Adipocitos/efectos de los fármacos , Animales , Ciclina D1/genética , Ciclina D1/metabolismo , Dieta Alta en Grasa/efectos adversos , Regulación hacia Abajo/efectos de los fármacos , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad/genética , Obesidad/metabolismo , Alcohol Feniletílico/administración & dosificaciónRESUMEN
Changes in adipose tissue mass must be accompanied by parallel changes in microcirculation. Investigating the mechanisms that regulate adipose tissue angiogenesis could lead to better understanding of adipose tissue function and reveal new potential therapeutic strategies. Angiogenesis is defined as the formation of new capillaries from existing microvessels. This process can be recapitulated in vitro, by incubation of tissue in extracellular matrix components in the presence of pro-angiogenic factors. Here, we describe a method to study angiogenesis from adipose tissue fragments obtained from mouse and human tissue. This assay can be used to define effects of diverse factors added in vitro, as well as the role of endogenously produced factors on angiogenesis. We also describe approaches to quantify angiogenic potential for the purpose of enabling comparisons between subjects, thus providing information on the role of physiological conditions of the donor on adipose tissue angiogenic potential.
Asunto(s)
Adipocitos/citología , Tejido Adiposo/crecimiento & desarrollo , Técnicas de Cultivo de Célula/métodos , Neovascularización Fisiológica , Tejido Adiposo/citología , Animales , Células Endoteliales/citología , Matriz Extracelular/fisiología , Humanos , Ratones , Microvasos/crecimiento & desarrolloRESUMEN
SCOPE: Daidzein is one of the major soy isoflavones. Following ingestion, daidzein is readily metabolized in the liver and converted into hydroxylated metabolites. One such metabolite is 6,7,4'-trihydroxyisoflavone (6,7,4'-THIF), which has been the focus of recent studies due to its various health benefits, however, its anti-adipogenic activity has not been investigated. Our objective was to determine the effects of 6,7,4'-THIF on adipogenesis in 3T3-L1 preadipocytes and elucidate the mechanisms of action involved. METHODS AND RESULTS: Adipogenesis was stimulated in 3T3-L1 preadipocytes. Both 6,7,4'-THIF and daidzein were treated in the presence and absence of mixture of isobutylmethylxanthine, dexamethasone, and insulin (MDI). We observed that 6,7,4'-THIF, but not daidzein, inhibited MDI-induced adipogenesis significantly at 40 and 80 µM, associated with decreased peroxisome proliferator-activated receptor-γ and C/EBP-α protein expression. 6,7,4'-THIF significantly suppressed MDI-induced lipid accumulation in the early stage of adipogenesis, attributable to a suppression of cell proliferation and the induction of cell cycle arrest. We also determined that 6,7,4'-THIF, but not daidzein, attenuated phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. 6,7,4'-THIF was found to inhibit PI3K activity via direct binding in an ATP-competitive manner. CONCLUSION: Our results suggest that 6,7,4'-THIF suppresses adipogenesis in 3T3-L1 preadipocytes by directly targeting PI3K. Soy isoflavones like 6,7,4'-THIF may have potential for development into novel treatment strategies for chronic obesity.
Asunto(s)
Adipogénesis/efectos de los fármacos , Isoflavonas/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Células 3T3-L1/efectos de los fármacos , Células 3T3-L1/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Unión Competitiva , Proteína alfa Potenciadora de Unión a CCAAT/metabolismo , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Dexametasona/farmacología , Regulación hacia Abajo/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Insulina/farmacología , Ratones , PPAR gamma/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismoRESUMEN
Alcoholic liver disease (ALD) is characterized by steatosis and upregulation of proinflammatory cytokines, including IL-1ß. IL-1ß, type I IL-1 receptor (IL-1R1), and IL-1 receptor antagonist (IL-1Ra) are all important regulators of the IL-1 signaling complex, which plays a role in inflammation. Furthermore, IL-1ß maturation is dependent on caspase-1 (Casp-1). Using IL-1Ra-treated mice as well as 3 mouse models deficient in regulators of IL-1ß activation (Casp-1 and ASC) or signaling (IL-1R1), we found that IL-1ß signaling is required for the development of alcohol-induced liver steatosis, inflammation, and injury. Increased IL-1ß was due to upregulation of Casp-1 activity and inflammasome activation. The pathogenic role of IL-1 signaling in ALD was attributable to the activation of the inflammasome in BM-derived Kupffer cells. Importantly, in vivo intervention with a recombinant IL-1Ra blocked IL-1 signaling and markedly attenuated alcohol-induced liver inflammation, steatosis, and damage. Furthermore, physiological doses of IL-1ß induced steatosis, increased the inflammatory and prosteatotic chemokine MCP-1 in hepatocytes, and augmented TLR4-dependent upregulation of inflammatory signaling in macrophages. In conclusion, we demonstrated that Casp-1-dependent upregulation of IL-1ß and signaling mediated by IL-1R1 are crucial in ALD pathogenesis. Our findings suggest a potential role of IL-1R1 inhibition in the treatment of ALD.