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1.
Pharmacy (Basel) ; 11(1)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36649024

RESUMO

Background: Community pharmacies are well-placed to deliver well-being interventions; however, to date, nothing has been produced specifically for this setting. The aim of this study was to develop a positive psychology intervention suitable for a community pharmacy setting with the goal of increasing the well-being of community members. Methods: Intervention development consisted of three steps: Step 1-identify the evidence-base and well-being model to underpin the basis of the intervention (Version 1); Step 2-model the intervention and gather user feedback to produce Version 2, and Step 3-revisit the evidence-base and refine the intervention to produce Version 3. Results: Findings from nine studies (seven RCTs, one cross-sectional, one N-1 design plus user feedback were applied to model a 6-week 'Prescribing Happiness (P-Hap)' intervention, underpinned by the PERMA model plus four other components from the positive psychology literature (Three Good Things, Utilising Your Signature Strengths in New Ways, Best Possible Selves and Character Strengths). A PERMA-based diary was designed to be completed 3 days a week as part of the intervention. Conclusions: This work is an important development which will direct the future implementation of interventions to support well-being in this novel setting. The next stage is to gain the perspectives of external stakeholders on the feasibility of delivering the P-Hap for its adoption into community pharmacy services in the future.

2.
PLoS One ; 13(1): e0190210, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29293579

RESUMO

Date palm fruit (Phoenix dactylifera) consumption reduces serum triglyceride levels in human subjects. The objective of this study was to prepare an extract from dates and determine whether it acts as a ligand for the farnesoid x receptor (FXR), a nuclear receptor important for maintaining triglyceride and cholesterol homeostasis. Freeze-dried extracts were isolated from California-grown dates (Deglet Noor and Medjool) from the 2014 and 2015 harvests, by means of liquid extraction and solid phase separation. Each date palm extract (DPE) was characterized via HPLC and MALDI-TOF mass spectrometry, and the procyanidin content was qualitatively determined. Extracts were tested to determine their ability to modulate nuclear receptor-mediated transactivation using transient transfection. The effect of DPE on FXR-target genes regulating bile acid absorption and transport was then assessed in vitro, in Caco-2 cells. Characterization reveals that DPE is a rich source of polyphenols including hydroxycinnamic acids, proanthocyanidins, and lipohilic polyphenols, and comprises 13% proanthocyanidins. Transactivation results show that DPE acts as a co-agonist ligand for both mouse and human FXR, wherein it activates bile acid-bound FXR greater than that seen with bile acid alone. Additionally, DPE alone activated a peroxisome proliferator activated receptor alpha (PPARα) chimera in a dose-dependent manner. Consistent with DPE as a co-agonist ligand for FXR, studies in Caco-2 cells reveal that co-incubation with bile acid, dose-dependently enhances the expression of fibroblast growth factor 19 (FGF19), compared to treatment with bile acid alone. In contrast, DPE inhibited bile acid-induced expression of ileal bile acid binding protein (IBABP). Our results demonstrate that DPE acts as a potent co-agonist ligand for FXR, and that it differentially regulates FXR-target gene expression in vitro in human intestinal cells. This study provides novel insight into a potential mechanism by which dates may exert a hypotriglyceridemic effect via FXR and modulation of bile acid homeostasis.


Assuntos
Phoeniceae/química , Extratos Vegetais/farmacologia , Receptores Citoplasmáticos e Nucleares/agonistas , Células CACO-2 , Humanos , Técnicas In Vitro , Ligantes , Receptores Citoplasmáticos e Nucleares/genética
3.
Curr Pharm Des ; 24(2): 158-170, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29189132

RESUMO

BACKGROUND: Cardiovascular disease (CVD) is currently the leading cause of death globally. The metabolic syndrome (MetS), a clustering of risk factors including hypertension, hyperglycemia, elevated low-density lipoprotein (LDL) cholesterol, reduced high-density lipoprotein (HDL) cholesterol and increased visceral adiposity, is a significant risk factor for the development of CVD. Non-alcoholic fatty liver disease (NAFLD), often referred to as the hepatic manifestation of MetS, is a constellation of progressive liver disorders closely linked to obesity, diabetes, and insulin resistance. NAFLD initially presents as relatively benign, non-progressive hepatic steatosis, but it may, in certain individuals, progress to nonalcoholic steatohepatitis, fibrosis, cirrhosis, or hepatocellular carcinoma. Currently, there are no validated treatments for NAFLD. Polyphenols are important bioactive dietary compounds and may represent a natural complementary and integrative therapy for the treatment of CVDassociated risk factors, including elevated serum cholesterol and triglyceride levels, as well as NAFLD. Understanding their molecular mechanisms of action is important in the design of future human intervention studies. METHODS: Several studies utilizing in vitro and in vivo models have helped to identify underlying molecular mechanisms of action of polyphenols. RESULTS: This review will highlight recent advances regarding the molecular actions of dietary procyanidins, with a special focus on those originating from procyanidin-rich grape seed extracts, with a focus on the signaling pathways utilized to exert beneficial metabolic effects. CONCLUSION: Modulation of nuclear receptor activity and histone deacetylase inhibition has been identified as underlying mechanisms contributing to procyanidin-mediated amelioration of dyslipidemia and steatosis.


Assuntos
Doenças Cardiovasculares/metabolismo , Polifenóis/metabolismo , Proantocianidinas/metabolismo , Transdução de Sinais , Animais , Doenças Cardiovasculares/tratamento farmacológico , Humanos , Polifenóis/administração & dosagem , Polifenóis/farmacologia , Proantocianidinas/administração & dosagem , Proantocianidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos
4.
Cell Biochem Funct ; 35(1): 12-32, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28083965

RESUMO

Dietary procyanidins have emerged as important bioactive components that regulate various metabolic pathways to maintain homeostasis. Grape seed procyanidin extract (GSPE), in particular, has demonstrated regulatory effects on bile acid and lipid metabolism in vivo. While numerous studies in rodent models have shown the potent hypolipidemic action of grape seed extracts, human studies have shown inconsistent results. This review will focus on the molecular mechanisms underlying the hypolipidemic actions of GSPE identified to date, specifically highlighting the effects exerted via nuclear receptors. Such evidence may provide avenues for future research in human subjects with GSPE as a therapeutic treatment for the prevention and amelioration of the metabolic syndrome and cardiovascular disease.


Assuntos
Biflavonoides/farmacologia , Ácidos e Sais Biliares/metabolismo , Catequina/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Proantocianidinas/farmacologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Vitis/química , Animais , Biflavonoides/química , Catequina/química , Colesterol/metabolismo , Extrato de Sementes de Uva/química , Modelos Animais , Proantocianidinas/química , Triglicerídeos/metabolismo , Vitis/metabolismo
5.
Mol Nutr Food Res ; 61(2)2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27624175

RESUMO

SCOPE: Histone deacetylases (HDACs) have emerged as epigenetic regulators of risk factors associated with the metabolic syndrome (MetS), and certain botanical extracts have proven to be potent HDAC inhibitors. Understanding the role of dietary procyanidins in HDAC inhibition is important in exploring the therapeutic potential of natural products. METHODS: C57BL/6 mice were gavaged with vehicle (water) or grape seed procyanidin extract (GSPE, 250 mg/kg) and terminated 14 h later. Liver and serum were harvested to assess the effect of GSPE on HDAC activity, histone acetylation, Pparα activity and target-gene expression, and serum lipid levels. RESULTS: GSPE increased histone acetylation and decreased Class I HDAC activity in vivo, and dose-dependently inhibited recombinant HDAC2 and 3 activities in vitro. Accordingly, Pparα gene and phosphorylated protein expression were increased, as were target genes involved in fatty acid catabolism, suggesting increased Pparα activity. Serum fibroblast growth factor 21 (Fgf21) was elevated, and triglyceride levels were reduced by 28%. CONCLUSION: GSPE regulates HDAC and Pparα activities to modulate lipid catabolism and reduce serum triglycerides in vivo.


Assuntos
Biflavonoides/farmacologia , Catequina/farmacologia , Extrato de Sementes de Uva/farmacologia , Inibidores de Histona Desacetilases/farmacologia , PPAR alfa/metabolismo , Proantocianidinas/farmacologia , Acetilação/efeitos dos fármacos , Animais , Apolipoproteína A-V/genética , Relação Dose-Resposta a Droga , Fatores de Crescimento de Fibroblastos/sangue , Fatores de Crescimento de Fibroblastos/genética , Extrato de Sementes de Uva/administração & dosagem , Extrato de Sementes de Uva/química , Histona Desacetilase 2/antagonistas & inibidores , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Histona Desacetilases/metabolismo , Histonas/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Triglicerídeos/sangue
6.
J Agric Food Chem ; 64(40): 7492-7501, 2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-27653593

RESUMO

Soy isoflavones exert beneficial health effects; however, their potential to ameliorate conditions associated with the metabolic syndrome (MetS) has not been studied in detail. In vitro and in vivo models were used to determine the effect of isoflavones on lipid metabolism, inflammation, and oxidative stress. In nude mice, consumption of Novasoy (NS) increased cholesterol and lipid metabolism gene expression, including Scd-1 (27.7-fold), Cyp4a14 (35.2-fold), and Cyp4a10 (9.5-fold), and reduced anti-inflammatory genes, including Cebpd (16.4-fold). A high-fat (HF) diet containing 0.4% (w/w) NS for 10 weeks significantly reduced percent weight gain (74.6 ± 2.5 vs 68.6 ± 3.5%) and hepatic lipid accumulation (20 ± 1.2 vs 27 ± 1.5%), compared to HF alone (p < 0.05) in C57BL/6J mice. NS also increased lipid oxidation and antioxidant gene expression while decreasing inflammatory cytokines. In vitro analysis in HepG2 cells revealed that genistein dose-dependently decreases oleic acid-induced lipid accumulation. Soy isoflavones may ameliorate symptoms associated with MetS via anti-inflammatory, antioxidant, and hypolipidemic modulation.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Isoflavonas/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Síndrome Metabólica/dietoterapia , Animais , Suplementos Nutricionais , Genisteína/farmacologia , Células Hep G2/efeitos dos fármacos , Humanos , Metabolismo dos Lipídeos/genética , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Síndrome Metabólica/etiologia , Camundongos Endogâmicos C57BL , Camundongos Nus , Ácido Oleico/farmacologia , Glycine max/química
7.
PLoS One ; 11(4): e0154305, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27111442

RESUMO

Bile acid (BA) sequestrants, lipid-lowering agents, may be prescribed as a monotherapy or combination therapy to reduce the risk of coronary artery disease. Over 33% of adults in the United States use complementary and alternative medicine strategies, and we recently reported that grape seed procyanidin extract (GSPE) reduces enterohepatic BA recirculation as a means to reduce serum triglyceride (TG) levels. The current study was therefore designed to assess the effects on BA, cholesterol and TG homeostatic gene expression following co-administration with GSPE and the BA sequestrant, cholestyramine (CHY). Eight-week old male C57BL/6 mice were treated for 4 weeks with either a control or 2% CHY-supplemented diet, after which, they were administered vehicle or GSPE for 14 hours. Liver and intestines were harvested and gene expression was analyzed. BA, cholesterol, non-esterified fatty acid and TG levels were also analyzed in serum and feces. Results reveal that GSPE treatment alone, and co-administration with CHY, regulates BA, cholesterol and TG metabolism differently than CHY administration alone. Notably, GSPE decreased intestinal apical sodium-dependent bile acid transporter (Asbt) gene expression, while CHY significantly induced expression. Administration with GSPE or CHY robustly induced hepatic BA biosynthetic gene expression, especially cholesterol 7α-hydroxylase (Cyp7a1), compared to control, while co-administration further enhanced expression. Treatment with CHY induced both intestinal and hepatic cholesterologenic gene expression, while co-administration with GSPE attenuated the CHY-induced increase in the liver but not intestine. CHY also induced hepatic lipogenic gene expression, which was attenuated by co-administration with GSPE. Consequently, a 25% decrease in serum TG levels was observed in the CHY+GSPE group, compared to the CHY group. Collectively, this study presents novel evidence demonstrating that GSPE provides additive and complementary efficacy as a lipid-lowering combination therapy in conjunction with CHY by attenuating hepatic cholesterol synthesis, enhancing BA biosynthesis and decreasing lipogenesis, which warrants further investigation.


Assuntos
Biflavonoides/metabolismo , Ácidos e Sais Biliares/metabolismo , Catequina/metabolismo , Colesterol/metabolismo , Resina de Colestiramina/metabolismo , Extrato de Sementes de Uva/farmacologia , Mucosa Intestinal/metabolismo , Fígado/metabolismo , Proantocianidinas/metabolismo , Animais , Peso Corporal , Fezes , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Homeostase , Lipídeos/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Triglicerídeos/metabolismo
8.
Mol Nutr Food Res ; 60(4): 727-36, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26718753

RESUMO

SCOPE: Understanding the molecular basis by which dietary procyanidins modulate triglyceride and cholesterol homeostasis has important implications for the use of natural products in the treatment and prevention of cardiovascular disease. METHODS: To determine whether modulation of bile acid (BA) homeostasis contributes to the hypotriglyceridemic action of grape seed procyanidin extract (GSPE) we examined the effect on genes regulating BA absorption, transport and synthesis in vitro, in Caco-2 cells, and in vivo, in wild type (C57BL/6) and farnesoid x receptor knockout (Fxr(-/-)) mice. RESULTS: We provide novel evidence demonstrating that GSPE is a naturally occurring gene-selective bile acid receptor modulator (BARM). Mechanistically, GSPE down-regulates genes involved in intestinal BA absorption and transport in an Fxr-dependent manner, resulting in decreased enterohepatic BA recirculation. This correlates with increased fecal BA output, decreased serum triglyceride and cholesterol levels, increased hepatic cholesterol 7α-hydroxylase (Cyp7a1), and decreased intestinal fibroblast growth factor 15 (Fgf15) expression. GSPE also increased hepatic HmgCoA reductase (Hmgcr) and synthase (Hmgcs1) expression, while concomitantly decreasing sterol regulatory element-binding protein 1c (Srebp1c). CONCLUSION: GSPE selectively regulates intestinal Fxr-target gene expression in vivo, and modulation of BA absorption and transport is a critical regulatory point for the consequential hypotriglyceridemic effects of GSPE.


Assuntos
Ácidos e Sais Biliares/metabolismo , Extrato de Sementes de Uva/farmacologia , Proantocianidinas/farmacologia , Receptores Citoplasmáticos e Nucleares/genética , Animais , Células CACO-2/efeitos dos fármacos , Colesterol/sangue , Regulação da Expressão Gênica/efeitos dos fármacos , Extrato de Sementes de Uva/química , Humanos , Absorção Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Citoplasmáticos e Nucleares/metabolismo , Triglicerídeos/sangue
9.
PLoS One ; 10(10): e0140267, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26458107

RESUMO

The objective of this study was to determine whether a grape seed procyanidin extract (GSPE) exerts a triglyceride-lowering effect in a hyperlipidemic state using the fructose-fed rat model and to elucidate the underlying molecular mechanisms. Rats were fed either a starch control diet or a diet containing 65% fructose for 8 weeks to induce hypertriglyceridemia. During the 9th week of the study, rats were maintained on their respective diet and administered vehicle or GSPE via oral gavage for 7 days. Fructose increased serum triglyceride levels by 171% after 9 weeks, compared to control, while GSPE administration attenuated this effect, resulting in a 41% decrease. GSPE inhibited hepatic lipogenesis via down-regulation of sterol regulatory element binding protein 1c and stearoyl-CoA desaturase 1 in the fructose-fed animals. GSPE increased fecal bile acid and total lipid excretion, decreased serum bile acid levels and increased the expression of genes involved in cholesterol synthesis. However, bile acid biosynthetic gene expression was not increased in the presence of GSPE and fructose. Serum cholesterol levels remained constant, while hepatic cholesterol levels decreased. GSPE did not modulate expression of genes responsible for esterification or biliary export of the newly synthesized cholesterol, but did increase fecal cholesterol excretion, suggesting that in the presence of GSPE and fructose, the liver may secrete more free cholesterol into the plasma which may then be shunted to the proximal small intestine for direct basolateral to apical secretion and subsequent fecal excretion. Our results demonstrate that GSPE effectively lowers serum triglyceride levels in fructose-fed rats after one week administration. This study provides novel insight into the mechanistic actions of GSPE in treating hypertriglyceridemia and demonstrates that it targets hepatic de novo lipogenesis, bile acid homeostasis and non-biliary cholesterol excretion as important mechanisms for reducing hypertriglyceridemia and hepatic lipid accumulation in the presence of fructose.


Assuntos
Biflavonoides/farmacologia , Catequina/farmacologia , Fezes/química , Frutose/efeitos adversos , Extrato de Sementes de Uva/química , Hipertrigliceridemia/tratamento farmacológico , Lipogênese/efeitos dos fármacos , Fígado/efeitos dos fármacos , Proantocianidinas/farmacologia , Animais , Ácidos e Sais Biliares/biossíntese , Ácidos e Sais Biliares/metabolismo , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/genética , Peso Corporal/efeitos dos fármacos , Colesterol/biossíntese , Colesterol/metabolismo , Dieta/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Hipertrigliceridemia/sangue , Hipertrigliceridemia/induzido quimicamente , Hipertrigliceridemia/metabolismo , Hipolipemiantes/farmacologia , Hipolipemiantes/uso terapêutico , Fígado/metabolismo , Fígado/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Wistar , Triglicerídeos/sangue
10.
Cell Biochem Funct ; 30(7): 531-51, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23027406

RESUMO

Nuclear hormone receptors (NHRs), as ligand-dependent transcription factors, have emerged as important mediators in the control of whole body metabolism. Because of the promiscuous nature of several members of this superfamily that have been found to bind ligand with lower affinity than the classical steroid NHRs, they consequently display a broader ligand selectivity. This promiscuous nature has facilitated various bioactive dietary components being able to act as agonist ligands for certain members of the NHR superfamily. By binding to these NHRs, bioactive dietary components are able to mediate changes in various metabolic pathways, including, glucose, cholesterol and triglyceride homeostasis among others. This review will provide a general overview of the nuclear hormone receptors that have been shown to be activated by dietary components. The physiological consequences of such receptor activation by these dietary components will then be discussed in more detail.


Assuntos
Redes e Vias Metabólicas , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Curcumina/metabolismo , Diterpenos/metabolismo , Flavonoides/metabolismo , Humanos , Receptores Nucleares Órfãos/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Probióticos/metabolismo , Receptores de Calcitriol/metabolismo , Receptores de Esteroides/metabolismo , Esteróis/metabolismo
11.
Mol Nutr Food Res ; 53(7): 805-14, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19496086

RESUMO

Consumption of dietary flavonoids has been associated with reduced mortality and risk of cardiovascular disease, partially by reducing triglyceridemia. We have previously reported that a grape seed procyanidin extract (GSPE) reduces postprandial triglyceridemia in normolipidemic animals signaling through the orphan nuclear receptor small heterodimer partner (SHP) a target of the bile acid receptor farnesoid X receptor (FXR). Our aim was to elucidate whether FXR mediates the hypotriglyceridemic effect of procyanidins. In FXR-driven luciferase expression assays GSPE dose-dependently enhanced FXR activity in the presence of chenodeoxycholic acid. GSPE gavage reduced triglyceridemia in wild type mice but not in FXR-null mice, revealing FXR as an essential mediator of the hypotriglyceridemic actions of procyanidins in vivo. In the liver, GSPE downregulated, in an FXR-dependent manner, the expression of the transcription factor steroid response element binding protein 1 (SREBP1) and several SREBP1 target genes involved in lipogenesis, and upregulated ApoA5 expression. Altogether, our results indicate that procyanidins lower triglyceridemia following the same pathway as bile acids: activation of FXR, transient upregulation of SHP expression and subsequent downregulation of SREBP1 expression. This study adds dietary procyanidins to the arsenal of FXR ligands with potential therapeutic use to combat hypertriglyceridemia, type 2 diabetes and metabolic syndrome.


Assuntos
Ácidos e Sais Biliares/farmacologia , Hipertrigliceridemia/prevenção & controle , Extratos Vegetais/farmacologia , Proantocianidinas/farmacologia , Receptores Citoplasmáticos e Nucleares/fisiologia , Animais , Chlorocebus aethiops , Extrato de Sementes de Uva , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Transcrição Gênica/efeitos dos fármacos
12.
J Nutr ; 139(5): 898-904, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19297428

RESUMO

Pregnane X receptor (PXR) is an important component of the body's adaptive defense system responsible for the elimination of various toxic xenobiotics. PXR activation by endogenous and exogenous chemicals, including steroids, antibiotics, bile acids, and herbal compounds, results in induction of drug metabolism. We investigated the ability of the isoflavones genistein, daidzein, and the daidzein metabolite equol to activate human and mouse PXR in vitro using cell-based transient transfection studies and primary hepatocytes and in vivo in a mouse model. In transient transfection assays, the isoflavones genistein and daidzein activate full-length, wild-type mouse PXR, but not a mutant form, with genistein being the most potent. In contrast, equol was a more potent activator of human PXR than genistein or daidzein. In a mammalian 2-hybrid assay, isoflavones induced recruitment of the coactivator steroid receptor coactivator 1 to PXR. When tested against the native human Cytochrome P450 3A4 (CYP3A4) promoter, equol was the more potent activator and treatment of human hepatocytes with equol increased CYP3A4 mRNA and immunoreactive protein expression. Treatment of wild-type, but not PXR(-/-), mouse hepatocytes showed that genistein and daidzein induced the expression of Cytochrome P450 3A11 (Cyp3A11) mRNA, whereas equol had no effect. Cyp3A11 mRNA was also induced in vivo in mice fed a soy protein-containing diet. The results presented herein demonstrate that there is a species-specific difference in the activation of PXR by isoflavones and equol.


Assuntos
Citocromo P-450 CYP3A/genética , Genisteína/farmacologia , Isoflavonas/farmacologia , Proteínas de Membrana/genética , Receptores de Esteroides/efeitos dos fármacos , Receptores de Esteroides/fisiologia , Animais , Carcinoma Hepatocelular , Linhagem Celular Tumoral , Chlorocebus aethiops , Citocromo P-450 CYP3A/análise , Equol , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Rim , Neoplasias Hepáticas , Masculino , Proteínas de Membrana/análise , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase , Receptor de Pregnano X , Regiões Promotoras Genéticas/genética , RNA Mensageiro/análise , Receptores de Esteroides/deficiência , Especificidade da Espécie , Transfecção
13.
Mol Nutr Food Res ; 52(10): 1172-81, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18720348

RESUMO

Hypertriglyceridemia is an independent risk factor in the development of cardiovascular diseases, and we have previously reported that oral administration of a grape seed procyanidin extract (GSPE) drastically decreases plasma levels of triglycerides (TG) and apolipoprotein B (ApoB) in normolipidemic rats, with a concomitant induction in the hepatic expression of the nuclear receptor small heterodimer partner (NR0B2/SHP). Our objective in this study was to elucidate whether SHP is the mediator of the reduction of TG-rich ApoB-containing lipoproteins triggered by GSPE. We show that GSPE inhibited TG and ApoB secretion in human hepatocarcinoma HepG2 cells and had and hypotriglyceridemic effect in wild-type mouse. The TG-lowering action of GSPE was abolished in HepG2 cells transfected with a SHP-specific siRNA and in a SHP-null mouse. Moreover, in mouse liver, GSPE downregulated several lipogenic genes, including steroid response element binding protein 1c (SREBP-1c), and upregulated carnitine palmitoyltransferase-1A (CPT-1A) and apolipoprotein A5 (ApoA5), in a SHP-dependent manner. In HepG2 cells GSPE also inhibited ApoB secretion, but in a SHP-independent manner. In conclusion, SHP is a key mediator of the hypotriglyceridemic response triggered by GSPE. This novel signaling pathway of procyanidins through SHP may be relevant to explain the health effects ascribed to the regular consumption of dietary flavonoids.


Assuntos
Apolipoproteínas B/biossíntese , Extratos Vegetais/farmacologia , Proantocianidinas/farmacologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Triglicerídeos/biossíntese , Animais , Apolipoproteínas B/efeitos dos fármacos , Carnitina O-Palmitoiltransferase/genética , Carnitina O-Palmitoiltransferase/metabolismo , Linhagem Celular , Inativação Gênica , Humanos , Hipertrigliceridemia/tratamento farmacológico , Hipertrigliceridemia/prevenção & controle , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Proantocianidinas/metabolismo , RNA Interferente Pequeno , Sementes/química , Transdução de Sinais , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Vitis/química
14.
Mol Endocrinol ; 21(7): 1603-16, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17456796

RESUMO

Cafestol, a diterpene present in unfiltered coffee brews such as Scandinavian boiled, Turkish, and cafetière coffee, is the most potent cholesterol-elevating compound known in the human diet. Several genes involved in cholesterol homeostasis have previously been shown to be targets of cafestol, including cholesterol 7alpha-hydroxylase (CYP7A1), the rate-limiting enzyme in bile acid biosynthesis. We have examined the mechanism by which cafestol elevates serum lipid levels. Changes in several lipid parameters were observed in cafestol-treated APOE3Leiden mice, including a significant increase in serum triglyceride levels. Microarray analysis of these mice identified alterations in hepatic expression of genes involved in lipid metabolism and detoxification, many of which are regulated by the nuclear hormone receptors farnesoid X receptor (FXR) and pregnane X receptor (PXR). Further studies demonstrate that cafestol is an agonist ligand for FXR and PXR, and that cafestol down-regulates expression of the bile acid homeostatic genes CYP7A1, sterol 12alpha-hydroxylase, and Na(+)-taurocholate cotransporting polypeptide in the liver of wild-type but not FXR null mice. Cafestol did not affect genes known to be up-regulated by FXR in the liver of wild-type mice, but did increase expression of the positive FXR-target genes intestinal bile acid-binding protein and fibroblast growth factor 15 (FGF15) in the intestine. Because FGF15 has recently been shown to function in an enterohepatic regulatory pathway to repress liver expression of bile acid homeostatic genes, its direct induction in the gut may account for indirect effects of cafestol on liver gene expression. PXR-dependent gene regulation of cytochrome P450 3A11 and other targets by cafestol was also only seen in the intestine. Using a double FXR/PXR knockout mouse model, we found that both receptors contribute to the cafestol-dependent induction of intestinal FGF15 gene expression. In conclusion, cafestol acts as an agonist ligand for both FXR and PXR, and this may contribute to its impact on cholesterol homeostasis.


Assuntos
Proteínas de Ligação a DNA/agonistas , Diterpenos/farmacologia , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores de Esteroides/agonistas , Fatores de Transcrição/agonistas , Animais , Apolipoproteína E3/genética , Colesterol 7-alfa-Hidroxilase/genética , Café/química , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Diterpenos/efeitos adversos , Diterpenos/metabolismo , Feminino , Fatores de Crescimento de Fibroblastos/genética , Humanos , Hipercolesterolemia/induzido quimicamente , Técnicas In Vitro , Ligantes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Modelos Biológicos , Receptor de Pregnano X , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares/deficiência , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Esteroides/deficiência , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional/efeitos dos fármacos
15.
J Steroid Biochem Mol Biol ; 97(3): 289-98, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16143518

RESUMO

The guinea pig adrenal gland, analogous to the human, possesses the capacity to synthesize C(19) steroids. In order to further understand the control of guinea pig adrenal steroidogenesis we undertook the characterization of the guinea pig 3beta-hydroxysteroid dehydrogenase/Delta(5)-Delta(4)-isomerase (3beta-HSD) expressed in the adrenal gland. A cDNA clone encoding guinea pig 3beta-HSD isolated from a guinea pig adrenal library is predicted to encode a protein of 373 amino acid residues and 41,475Da. Ribonuclease protection assay suggests that this cDNA corresponds to the predominant, if not the sole, mRNA species detectable in total RNA from the guinea pig adrenal gland, ovary and testis. The guinea pig 3beta-HSD shows a similar affinity for both pregnenolone and dehydroepiandrosterone, and in addition, a 17beta-HSD type II-like activity was also observed. A phylogenetical analysis of the 3beta-HSD gene family demonstrates that the guinea pig is in a parallel branch to the myomorpha group supporting the hypothesis that the guinea pig lineage has branched off after the divergence among primates, artiodactyls and rodents, suggesting the paraphyly of the order rodentia.


Assuntos
Glândulas Suprarrenais/enzimologia , Complexos Multienzimáticos/classificação , Complexos Multienzimáticos/metabolismo , Ovário/enzimologia , Progesterona Redutase/classificação , Progesterona Redutase/metabolismo , Esteroide Isomerases/classificação , Esteroide Isomerases/metabolismo , Testículo/enzimologia , Sequência de Aminoácidos , Animais , DNA Complementar/genética , Desidroepiandrosterona/metabolismo , Feminino , Cobaias , Masculino , Dados de Sequência Molecular , Complexos Multienzimáticos/genética , Filogenia , Pregnenolona/metabolismo , Progesterona Redutase/genética , RNA Mensageiro/análise , Esteroide Isomerases/genética
16.
J Nutr Biochem ; 16(6): 321-30, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15936643

RESUMO

Consumption of soy has been demonstrated to reduce circulating cholesterol levels, most notably reducing low-density lipoprotein (LDL) cholesterol levels in hypercholesterolemic individuals. The component or components that might be responsible for this effect is still a matter of debate or controversy among many researchers. Candidate agents include an activity of soy protein itself, bioactive peptides produced during the digestive process, or the soy isoflavones. Although soy intake may provide other health benefits including preventative or remediative effects on cancer, osteoporosis and symptoms of menopause, this review will focus on isoflavones as agents affecting lipid metabolism. Isoflavones were first discovered as a bioactive agent disrupting estrogen action in female sheep, thereby earning the often-used term 'phytoestrogens'. Subsequent work confirmed the ability of isoflavones to bind to estrogen receptors. Along with the cholesterol-lowering effect of soy intake, research that is more recent has pointed to a beneficial antidiabetic effect of soy intake, perhaps mediated by soy isoflavones. The two common categories of antidiabetic drugs acting on nuclear receptors known as peroxisome proliferator activated receptors (PPARs) are the fibrates and glitazones. We and others have recently asked the research question 'do the soy isoflavones have activities as either "phytofibrates" or "phytoglitazones"?' Such an activity should be able to be confirmed both in vivo and in vitro. In both the in vivo and in vitro cases, this action has indeed been confirmed. Further work suggests a possible action of isoflavones similar to the nonestrogenic ligands that bind the estrogen-related receptors (ERRs). Recently, these receptors have been demonstrated to contribute to lipolytic processes. Finally, evaluation of receptor activation studies suggests that thyroid receptor activation may provide additional clues explaining the metabolic action of isoflavones. The recent advances in the discovery and evaluation of the promiscuous nuclear receptors that bind many different chemical ligands should prove to help explain some of the biological effects of soy isoflavones and other phytochemicals.


Assuntos
Glycine max/química , Isoflavonas/farmacologia , Fitoestrógenos/farmacologia , Receptores Citoplasmáticos e Nucleares/efeitos dos fármacos , Animais , Feminino , Humanos , Metabolismo dos Lipídeos , Receptores Ativados por Proliferador de Peroxissomo/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/fisiologia , Receptores de Estrogênio/efeitos dos fármacos , Receptores de Estrogênio/fisiologia
17.
Endocr Rev ; 26(4): 525-82, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15632317

RESUMO

The 3beta-hydroxysteroid dehydrogenase/Delta(5)-Delta(4) isomerase (3beta-HSD) isoenzymes are responsible for the oxidation and isomerization of Delta(5)-3beta-hydroxysteroid precursors into Delta(4)-ketosteroids, thus catalyzing an essential step in the formation of all classes of active steroid hormones. In humans, expression of the type I isoenzyme accounts for the 3beta-HSD activity found in placenta and peripheral tissues, whereas the type II 3beta-HSD isoenzyme is predominantly expressed in the adrenal gland, ovary, and testis, and its deficiency is responsible for a rare form of congenital adrenal hyperplasia. Phylogeny analyses of the 3beta-HSD gene family strongly suggest that the need for different 3beta-HSD genes occurred very late in mammals, with subsequent evolution in a similar manner in other lineages. Therefore, to a large extent, the 3beta-HSD gene family should have evolved to facilitate differential patterns of tissue- and cell-specific expression and regulation involving multiple signal transduction pathways, which are activated by several growth factors, steroids, and cytokines. Recent studies indicate that HSD3B2 gene regulation involves the orphan nuclear receptors steroidogenic factor-1 and dosage-sensitive sex reversal adrenal hypoplasia congenita critical region on the X chromosome gene 1 (DAX-1). Other findings suggest a potential regulatory role for STAT5 and STAT6 in transcriptional activation of HSD3B2 promoter. It was shown that epidermal growth factor (EGF) requires intact STAT5; on the other hand IL-4 induces HSD3B1 gene expression, along with IL-13, through STAT 6 activation. However, evidence suggests that multiple signal transduction pathways are involved in IL-4 mediated HSD3B1 gene expression. Indeed, a better understanding of the transcriptional factors responsible for the fine control of 3beta-HSD gene expression may provide insight into mechanisms involved in the functional cooperation between STATs and nuclear receptors as well as their potential interaction with other signaling transduction pathways such as GATA proteins. Finally, the elucidation of the molecular basis of 3beta-HSD deficiency has highlighted the fact that mutations in the HSD3B2 gene can result in a wide spectrum of molecular repercussions, which are associated with the different phenotypic manifestations of classical 3beta-HSD deficiency and also provide valuable information concerning the structure-function relationships of the 3beta-HSD superfamily. Furthermore, several recent studies using type I and type II purified enzymes have elegantly further characterized structure-function relationships responsible for kinetic differences and coenzyme specificity.


Assuntos
Complexos Multienzimáticos/genética , Progesterona Redutase/genética , Esteroide Isomerases/genética , Glândulas Suprarrenais/enzimologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Evolução Molecular , Feminino , Regulação Enzimológica da Expressão Gênica , Gônadas/enzimologia , Humanos , Isoenzimas , Masculino , Dados de Sequência Molecular , Complexos Multienzimáticos/química , Complexos Multienzimáticos/deficiência , Complexos Multienzimáticos/metabolismo , Especificidade de Órgãos , Filogenia , Placenta/enzimologia , Gravidez , Progesterona Redutase/química , Progesterona Redutase/deficiência , Progesterona Redutase/metabolismo , Regiões Promotoras Genéticas/genética , Especificidade da Espécie , Esteroide Isomerases/química , Esteroide Isomerases/deficiência , Esteroide Isomerases/metabolismo , Relação Estrutura-Atividade
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