RESUMEN
BACKGROUND: Obesity and insulin resistance/diabetes are important risk factors for cardiovascular diseases and demand safe and efficacious therapeutics. OBJECTIVE: To assess the effects of a new thiazolidine compound-GQ-11-on obesity and insulin resistance induced by a diabetogenic diet in LDL receptor-deficient (LDLr-/-) mice. METHODS: Molecular docking simulations of GQ-11, PPARα and PPARγ structures were performed. Male C57BL/6J LDLr-/- mice fed a diabetogenic diet for 24 weeks were treated with vehicle, GQ-11 or pioglitazone or (20 mg/kg/day) for 28 days by oral gavage. Glucose tolerance test, insulin, HOMA-IR, adipokines (leptin, adiponectin) and the lipid profile were assessed after treatment. Adipose tissue was analysed by X-ray analysis and morphometry; gene and protein expression were evaluated by real-time PCR and western blot, respectively. RESULTS: GQ-11 showed partial agonism to PPARγ and PPARα. In vivo, treatment with GQ-11 ameliorated insulin sensitivity and did not modify subcutaneous adipose tissue and body weight gain. In addition, GQ-11 restored adipokine imbalance induced by a diabetogenic diet and enhanced Glut-4 expression in the adipose tissue. Improved insulin sensitivity was also associated with lower levels of MCP-1 and higher levels of IL-10. Furthermore, GQ-11 reduced triglycerides and VLDL cholesterol and increased HDL-cholesterol by upregulation of Apoa1 and Abca1 gene expression in the liver. CONCLUSION: GQ-11 is a partial/dual PPARα/γ agonist that demonstrates anti-diabetic effects. Additionally, it improves the lipid profile and ameliorates chronic inflammation associated with obesity in atherosclerosis-prone mice.
Asunto(s)
Indoles/farmacología , Obesidad/metabolismo , Receptores Activados del Proliferador del Peroxisoma/agonistas , Receptores de LDL/metabolismo , Tiazolidinas/farmacología , Adipoquinas/sangre , Animales , Peso Corporal/efectos de los fármacos , Indoles/química , Inflamación/metabolismo , Lípidos/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Obesos , Receptores de LDL/genética , Tiazolidinas/químicaRESUMEN
Peroxisome proliferator-activated receptor gamma (PPARγ) regulates multiple pathways involved in the pathogenesis of obesity and atherosclerosis. Here, we evaluated the therapeutic potential of GQ-177, a new thiazolidinedione, on diet-induced obesity and atherosclerosis. The intermolecular interaction between PPARγ and GQ-177 was examined by virtual docking and PPAR activation was determined by reporter gene assay identifying GQ-177 as a partial and selective PPARγ agonist. For the evaluation of biological activity of GQ-177, low-density lipoprotein receptor-deficient (LDLr(-/-)) C57/BL6 mice were fed either a high fat diabetogenic diet (diet-induced obesity), or a high fat atherogenic diet, and treated with vehicle, GQ-177 (20mg/kg/day), pioglitazone (20mg/kg/day, diet-induced obesity model) or rosiglitazone (15mg/kg/day, atherosclerosis model) for 28 days. In diet-induced obesity mice, GQ-177 improved insulin sensitivity and lipid profile, increased plasma adiponectin and GLUT4 mRNA in adipose tissue, without affecting body weight, food consumption, fat accumulation and bone density. Moreover, GQ-177 enhanced hepatic mRNA levels of proteins involved in lipid metabolism. In the atherosclerosis mice, GQ-177 inhibited atherosclerotic lesion progression, increased plasma HDL and mRNA levels of PPARγ and ATP-binding cassette A1 in atherosclerotic lesions. GQ-177 acts as a partial PPARγ agonist that improves obesity-associated insulin resistance and dyslipidemia with atheroprotective effects in LDLr(-/-) mice.
Asunto(s)
Aterosclerosis/metabolismo , Obesidad/metabolismo , PPAR gamma/agonistas , PPAR gamma/metabolismo , Receptores de LDL/genética , Sulfonas/farmacología , Tiazolidinedionas/farmacología , Adiponectina/genética , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Animales , Aorta Torácica/patología , Aterosclerosis/sangre , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/patología , Densidad Ósea , Línea Celular , HDL-Colesterol/sangre , Factores de Crecimiento de Fibroblastos/genética , Transportador de Glucosa de Tipo 4/genética , Humanos , Leptina/genética , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones Noqueados , Modelos Moleculares , Miocardio/metabolismo , Obesidad/sangre , Obesidad/tratamiento farmacológico , Obesidad/patología , Sulfonas/uso terapéutico , Tiazolidinedionas/uso terapéuticoRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Propolis has long been used as a popular folk medicine due to its wide spectrum of alleged biological and pharmaceutical properties. In Chile, propolis is widely used by folklore medicine as an anti-inflammatory agent; however, this property has not been demonstrated by scientific methods. AIM OF THE STUDY: The objective of this study was to determine the anti-inflammatory activity in vivo and in vitro and to establish the phenolic profile of propolis collected in two localities in Región Metropolitana de Santiago (RM), Chile. MATERIALS AND METHODS: Propolis was collected in the areas of Caleu and Buin, RM Chile. Following that, the samples were unwaxed to obtain the global ethanolic extracts of propolis (EEPs) and, from these, the serial extracts of dichloromethane (EEP-DCMs) and ethanol (EEP-EtOHs). The topic anti-inflammatory effect was evaluated through mice ear edema induced by arachidonic acid (AA) and 12-O-tetradecanoylphorbol-13-acetate (TPA) at a dose of 3 mg/ear. Nitric oxide (NO) measurements were determined spectrophotometrically (Greiss reagent) by the accumulation of nitrite in the medium of macrophages RAW 264.7 stimulated with the lipopolysaccharide (LPS, 1 µg/mL) for 20 h at different concentrations of the EEPs, EEP-DCMs and EEP-EtOHs (6.25-50.00 µg/mL). The content of total phenols and flavonoids were determined through the methods of Folin-Ciocalteau and AlCl3, respectively. The profile of phenolic compounds was determined by HPLC-UV-ESI-MS/MS. RESULTS: The EEP-EtOH (64%) and EEP (59%) of Buin were the most active in the inflammation induced by TPA and AA respectively, being the anti-inflammatory effect stronger than the same Caleu extracts. Regarding the release of NO, all the extracts from the Buin propolis inhibited significantly its release in a concentration-dependent manner, this inhibition was stronger than the extracts from Caleu propolis. CONCLUSIONS: Our research shows for the first time a comparative study of the topical in vivo activity of two Chilean propolis. Both propolis showed in vivo topical anti-inflammatory activity against AA and TPA, the most active was Buin propolis and this difference is due in part to the variations in total phenols and flavonoids content and the phenolic profile. The phenols and flavonoids content of Buin propolis was higher than Caleu propolis. The extracts from Buin propolis result in a lower release of NO.
Asunto(s)
Antiinflamatorios/uso terapéutico , Mezclas Complejas/uso terapéutico , Flavonoides/uso terapéutico , Fenoles/uso terapéutico , Própolis , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Ácido Araquidónico , Línea Celular , Supervivencia Celular/efectos de los fármacos , Chile , Mezclas Complejas/química , Mezclas Complejas/farmacología , Edema/inducido químicamente , Edema/tratamiento farmacológico , Edema/metabolismo , Flavonoides/análisis , Flavonoides/farmacología , Masculino , Ratones , Óxido Nítrico/metabolismo , Fenoles/análisis , Fenoles/farmacología , Acetato de TetradecanoilforbolRESUMEN
Thiazolidinediones (TZDs) are peroxisome proliferator-activated receptor γ (PPARγ) agonists that improve insulin-mediated glucose uptake and possess beneficial vasculoprotective actions. However, because undesirable side effects are associated with these drugs, novel TZDs are under development. In this study, we evaluated the biological activity of LYSO-7, a new indole-thiazolidine, on PPAR activation, inflammation and atherogenesis using a gene reporter assay, lipopolysaccharide (LPS)-activated RAW 264.7 cell culture, and a low-density lipoprotein receptor knockout (LDLr(-/-)) mouse model of atherosclerosis. LYSO-7 shows low cytotoxicity in RAW 264.7 cells and at 2.5µmol/L induces PPARα and PPARγ transactivation as well as inhibits LPS-induced nitrite production and the mRNA gene expression levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), vascular cell adhesion molecule-1 (VCAM-1) and monocyte chemoattractant protein-1 (MCP-1). In addition, treatment with LYSO-7 reduces the development of atherosclerosis in LDLr(-/-) mice, improves the lipid profile, blood glucose levels, and downregulates CD40 and CD40L expression without affecting the body weight of the animals. Altogether, our data show that LYSO-7 possesses anti-inflammatory properties and that treatment with this TZD attenuates atherosclerosis progression in LDLr(-/-) mice by modulating lipid metabolism and inflammation. Thus, LYSO-7 shows potential as a new drug candidate for the treatment of atherosclerosis.
Asunto(s)
Aterosclerosis/metabolismo , Aterosclerosis/prevención & control , Indoles/uso terapéutico , Receptores de LDL/deficiencia , Tiazolidinedionas/uso terapéutico , Tiazolidinas/uso terapéutico , Animales , Línea Celular , Indoles/farmacología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores Activados del Proliferador del Peroxisoma/agonistas , Tiazolidinedionas/farmacología , Tiazolidinas/farmacologíaRESUMEN
Previously, we demonstrated that benznidazole (BZL), known for its antiparasitic action on Trypanosoma cruzi, modulates pro-inflammatory cytokines and NO release in macrophages by inhibiting NF-kappaB. We now proceeded to elucidate the molecular mechanisms by which BZL exerts its inhibitory action on NF-kappaB. We demonstrated that the inhibitory effect of BZL is not extended to other macrophage responses, since it did not inhibit other typical hallmarks of macrophage activation such as phagocytosis, MHC-II molecules expression or production of reactive oxygen species (ROS) by NADPH oxidase. BZL was able to interfere specifically with the activation of NF-kappaB pathway without affecting AP-1 activation in RAW 264.7 macrophages, not only in LPS-mediated activation, but also for other stimuli, such as pro-inflammatory cytokines (IL-1beta, TNF-alpha), PMA or H(2)O(2). Also, BZL delayed the activation of p38 MAPK, but not that of ERK1/2 and JNK. Finally, treatment with BZL inhibited IkappaBalpha phosporylation and hence its degradation, whereas it did not block IkappaB kinase (IKK) alpha/beta phosphorylation. Collectively, BZL behaves as a broad range specific inhibitor of NF-kappaB activation, independently of the stimuli tested.