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1.
Acta Diabetol ; 59(12): 1589-1596, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36044097

RESUMO

AIMS: Disturbances in circadian rhythms may promote cardiometabolic disorders in rotating night shift workers (r-NSWs). We hypothesized that timed light therapy might reverse disrupted circadian rhythms and glucose intolerance observed among r-NSWs). METHODS: R-NSWs were randomly assigned to a protocol that included 12 weeks on followed by 12 weeks off light therapy (n = 13; 6 men; mean age, 39.5 ± 7.3 years) or a no-treatment control group (n = 9; 3 men; mean age 41.7 ± 6.3 years). Experimental and control participants underwent identical metabolic evaluations that included anthropometric, metabolic (including oral glucose tolerance tests), lipid, and inflammation-associated parameters together with an assessment of sleep quality and expression of circadian transcription factors REV-ERBα and BMAL1 in peripheral blood mononuclear cells (PBMCs) at baseline, 12 weeks, and 24 weeks of the protocol. RESULTS: Twelve weeks of warm white-light exposure (10,000 lx at 35 cm for 30 min per day) had no impact on sleep, metabolic, or inflammation-associated parameters among r-NSWs in the experimental group. However, our findings revealed significant decreases in REV-ERBα gene expression (p = 0.048) and increases in the REV-ERBα/BMAL1 ratio (p = 0.040) compared to baseline in PBMCs isolated from this cohort. Diminished expression of REV-ERBα persisted, although the REV-ERBα/BMAL1 ratio returned to baseline levels after the subsequent 12-day wash-out period. CONCLUSIONS: Our results revealed that intermittent light therapy had no impact on inflammatory parameters or glucose tolerance in a defined cohort of r-NSWs. However, significant changes in the expression of circadian clock genes were detected in PBMCs of these subjects undergoing light therapy.


Assuntos
Fatores de Transcrição ARNTL , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/genética , Fatores de Transcrição ARNTL/genética , Leucócitos Mononucleares/metabolismo , Ritmo Circadiano/genética , Fototerapia , Inflamação , Glucose , Lipídeos
2.
Cell Metab ; 34(7): 1054-1063.e7, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35716660

RESUMO

Liraglutide, an anti-diabetic drug and agonist of the glucagon-like peptide one receptor (GLP1R), has recently been approved to treat obesity in individuals with or without type 2 diabetes. Despite its extensive metabolic benefits, the mechanism and site of action of liraglutide remain unclear. Here, we demonstrate that liraglutide is shuttled to target cells in the mouse hypothalamus by specialized ependymoglial cells called tanycytes, bypassing the blood-brain barrier. Selectively silencing GLP1R in tanycytes or inhibiting tanycytic transcytosis by botulinum neurotoxin expression not only hampers liraglutide transport into the brain and its activation of target hypothalamic neurons, but also blocks its anti-obesity effects on food intake, body weight and fat mass, and fatty acid oxidation. Collectively, these striking data indicate that the liraglutide-induced activation of hypothalamic neurons and its downstream metabolic effects are mediated by its tanycytic transport into the mediobasal hypothalamus, strengthening the notion of tanycytes as key regulators of metabolic homeostasis.


Assuntos
Diabetes Mellitus Tipo 2 , Liraglutida , Animais , Barreira Hematoencefálica , Diabetes Mellitus Tipo 2/metabolismo , Células Ependimogliais , Hipotálamo/metabolismo , Liraglutida/farmacologia , Camundongos , Obesidade/tratamento farmacológico , Obesidade/metabolismo
3.
Gut ; 71(4): 807-821, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33903148

RESUMO

OBJECTIVE: We evaluated the influence of sex on the pathophysiology of non-alcoholic fatty liver disease (NAFLD). We investigated diet-induced phenotypic responses to define sex-specific regulation between healthy liver and NAFLD to identify influential pathways in different preclinical murine models and their relevance in humans. DESIGN: Different models of diet-induced NAFLD (high-fat diet, choline-deficient high-fat diet, Western diet or Western diet supplemented with fructose and glucose in drinking water) were compared with a control diet in male and female mice. We performed metabolic phenotyping, including plasma biochemistry and liver histology, untargeted large-scale approaches (liver metabolome, lipidome and transcriptome), gene expression profiling and network analysis to identify sex-specific pathways in the mouse liver. RESULTS: The different diets induced sex-specific responses that illustrated an increased susceptibility to NAFLD in male mice. The most severe lipid accumulation and inflammation/fibrosis occurred in males receiving the high-fat diet and Western diet, respectively. Sex-biased hepatic gene signatures were identified for these different dietary challenges. The peroxisome proliferator-activated receptor α (PPARα) co-expression network was identified as sexually dimorphic, and in vivo experiments in mice demonstrated that hepatocyte PPARα determines a sex-specific response to fasting and treatment with pemafibrate, a selective PPARα agonist. Liver molecular signatures in humans also provided evidence of sexually dimorphic gene expression profiles and the sex-specific co-expression network for PPARα. CONCLUSIONS: These findings underscore the sex specificity of NAFLD pathophysiology in preclinical studies and identify PPARα as a pivotal, sexually dimorphic, pharmacological target. TRIAL REGISTRATION NUMBER: NCT02390232.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Feminino , Humanos , Metabolismo dos Lipídeos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , PPAR alfa/metabolismo
4.
Nutrients ; 13(10)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34684356

RESUMO

BACKGROUND: Carotenoids and docosahexaenoic acid (DHA) were identified as essential components for eye health and are both naturally present in eggs. OBJECTIVE: We aimed to evaluate the effect of the daily consumption of two eggs enriched with lutein/zeaxanthin and DHA on macular pigment optical density (MPOD) and on circulating xanthophyll and fatty acid concentrations in healthy participants. METHODS: Ninety-nine healthy volunteers consumed either two standard eggs or two enriched eggs per day for 4 months. MPOD was measured at baseline (V0) and at follow-up (V4) using a modified confocal scanning laser ophthalmoscope (primary outcome). Blood samples were collected to determine total plasma and lipoprotein fatty acids and lutein/zeaxanthin compositions at V0 and V4 (secondary outcomes). RESULTS: A slight but significant increase in MPOD was observed for all study participants consuming two eggs per day for 4 months at all eccentricities (0.5°, 1°, 2°, and 4°). Plasma and lipoprotein lutein, zeaxanthin, and DHA concentrations significantly increased in both groups but were greater in the enriched group (for the enriched group (V0 vs. V4): lutein, 167 vs. 369 ng/mL; zeaxanthin, 17.7 vs. 29.2 ng/mL; DHA, 1.89 vs. 2.56% of total fatty acids). Interestingly, lutein from high-density lipoprotein (HDL) was strongly correlated with MPOD at 0.5 and 1° eccentricities (rho = 0.385, p = 0.008, and rho = 0.461, p = 0.001, respectively). CONCLUSIONS: MPOD was slightly increased in both groups. Lutein, zeaxanthin, and DHA plasma concentrations were strongly enhanced in the enriched group compared with the standard group. A significant correlation was found between MPOD level and lutein concentration in HDL.


Assuntos
Ácidos Docosa-Hexaenoicos/sangue , Alimentos Fortificados , Luteína/sangue , Pigmento Macular/sangue , Adulto , Eritrócitos/metabolismo , Feminino , Humanos , Lipoproteínas/sangue , Masculino , Fenômenos Ópticos , Cooperação do Paciente , Xantofilas/sangue , Adulto Jovem , Zeaxantinas/sangue
5.
Cell Metab ; 33(7): 1483-1492.e10, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-33887197

RESUMO

Bile acids (BAs) improve metabolism and exert anti-obesity effects through the activation of the Takeda G protein-coupled receptor 5 (TGR5) in peripheral tissues. TGR5 is also found in the brain hypothalamus, but whether hypothalamic BA signaling is implicated in body weight control and obesity pathophysiology remains unknown. Here we show that hypothalamic BA content is reduced in diet-induced obese mice. Central administration of BAs or a specific TGR5 agonist in these animals decreases body weight and fat mass by activating the sympathetic nervous system, thereby promoting negative energy balance. Conversely, genetic downregulation of hypothalamic TGR5 expression in the mediobasal hypothalamus favors the development of obesity and worsens established obesity by blunting sympathetic activity. Lastly, hypothalamic TGR5 signaling is required for the anti-obesity action of dietary BA supplementation. Together, these findings identify hypothalamic TGR5 signaling as a key mediator of a top-down neural mechanism that counteracts diet-induced obesity.


Assuntos
Ácidos e Sais Biliares/metabolismo , Obesidade/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Peso Corporal/genética , Metabolismo Energético/genética , Células HEK293 , Humanos , Hipotálamo/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Camundongos Transgênicos , Obesidade/genética , Obesidade/prevenção & controle , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais/fisiologia
6.
J Hypertens ; 39(8): 1678-1688, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33710166

RESUMO

OBJECTIVES: Night shift work is associated with high rates of hypertension and cardiometabolic disease, which are linked to disrupted circadian rhythms. We hypothesized that timed light therapy might improve disrupted circadian rhythms and stabilize diurnal control of blood pressure and glucose in night shift workers. METHODS: We randomized 24 rotating night shift workers (mean age, 36 ±â€Š13 years, 7 men) who had spent a median of 6 years on rotating night shifts (median, six night shifts per month) to 12 weeks of light therapy or no intervention and compared them with 12 daytime workers (37 ±â€Š11 years, 6 men). We measured oral glucose tolerance (OGTT), 24-h blood pressure and arterial stiffness, and the circadian profiles of melatonin, cortisol, metanephrine and nor-metanephrine at baseline, after 12 weeks of intervention, and 12 weeks after the end of intervention. RESULTS: At baseline, fewer night shift workers showed dipper status as compared with daytime workers (29 vs. 58%; P < 0.001). After 12 weeks of light therapy, there was a highly significant increase in the proportion of dippers (to 58%; P < 0.0001). We also observed a significant decrease in serum glucose during OGTT in the light therapy group (-22%; P < 0.05) with no change in serum insulin. Whilst circadian profiles of melatonin and cortisol were unchanged, plasma metanephrine and nor-metanephrine levels were significantly reduced in the light therapy group (P < 0.01). CONCLUSION: Timed light therapy improves diurnal blood pressure control and glucose tolerance in rotating night shift workers. This effect is unrelated to melatonin and cortisol but is paralleled by reduced catecholamine levels.


Assuntos
Catecolaminas , Melatonina , Adulto , Pressão Sanguínea , Ritmo Circadiano , Humanos , Masculino , Pessoa de Meia-Idade , Fototerapia , Adulto Jovem
7.
Sci Rep ; 10(1): 174, 2020 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-31932631

RESUMO

The gut microbiota participates in the control of energy homeostasis partly through fermentation of dietary fibers hence producing short-chain fatty acids (SCFAs), which in turn promote the secretion of the incretin Glucagon-Like Peptide-1 (GLP-1) by binding to the SCFA receptors FFAR2 and FFAR3 on enteroendocrine L-cells. We have previously shown that activation of the nuclear Farnesoid X Receptor (FXR) decreases the L-cell response to glucose. Here, we investigated whether FXR also regulates the SCFA-induced GLP-1 secretion. GLP-1 secretion in response to SCFAs was evaluated ex vivo in murine colonic biopsies and in colonoids of wild-type (WT) and FXR knock-out (KO) mice, in vitro in GLUTag and NCI-H716 L-cells activated with the synthetic FXR agonist GW4064 and in vivo in WT and FXR KO mice after prebiotic supplementation. SCFA-induced GLP-1 secretion was blunted in colonic biopsies from GW4064-treated mice and enhanced in FXR KO colonoids. In vitro FXR activation inhibited GLP-1 secretion in response to SCFAs and FFAR2 synthetic ligands, mainly by decreasing FFAR2 expression and downstream Gαq-signaling. FXR KO mice displayed elevated colonic FFAR2 mRNA levels and increased plasma GLP-1 levels upon local supply of SCFAs with prebiotic supplementation. Our results demonstrate that FXR activation decreases L-cell GLP-1 secretion in response to inulin-derived SCFA by reducing FFAR2 expression and signaling. Inactivation of intestinal FXR using bile acid sequestrants or synthetic antagonists in combination with prebiotic supplementation may be a promising therapeutic approach to boost the incretin axis in type 2 diabetes.


Assuntos
Colo/metabolismo , Ácidos Graxos Voláteis/farmacologia , Peptídeo 1 Semelhante ao Glucagon/antagonistas & inibidores , Microbiota , Receptores Citoplasmáticos e Nucleares/fisiologia , Animais , Colo/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo
9.
Gut ; 67(2): 271-283, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28377388

RESUMO

OBJECTIVE: To investigate the beneficial role of prebiotics on endothelial dysfunction, an early key marker of cardiovascular diseases, in an original mouse model linking steatosis and endothelial dysfunction. DESIGN: We examined the contribution of the gut microbiota to vascular dysfunction observed in apolipoprotein E knockout (Apoe-/-) mice fed an n-3 polyunsaturated fatty acid (PUFA)-depleted diet for 12 weeks with or without inulin-type fructans (ITFs) supplementation for the last 15 days. Mesenteric and carotid arteries were isolated to evaluate endothelium-dependent relaxation ex vivo. Caecal microbiota composition (Illumina Sequencing of the 16S rRNA gene) and key pathways/mediators involved in the control of vascular function, including bile acid (BA) profiling, gut and liver key gene expression, nitric oxide and gut hormones production were also assessed. RESULTS: ITF supplementation totally reverses endothelial dysfunction in mesenteric and carotid arteries of n-3 PUFA-depleted Apoe-/- mice via activation of the nitric oxide (NO) synthase/NO pathway. Gut microbiota changes induced by prebiotic treatment consist in increased NO-producing bacteria, replenishment of abundance in Akkermansia and decreased abundance in bacterial taxa involved in secondary BA synthesis. Changes in gut and liver gene expression also occur upon ITFs suggesting increased glucagon-like peptide 1 production and BA turnover as drivers of endothelium function preservation. CONCLUSIONS: We demonstrate for the first time that ITF improve endothelial dysfunction, implicating a short-term adaptation of both gut microbiota and key gut peptides. If confirmed in humans, prebiotics could be proposed as a novel approach in the prevention of metabolic disorders-related cardiovascular diseases.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Frutanos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Prebióticos , Aminopeptidases/genética , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Bactérias/efeitos dos fármacos , Ácidos e Sais Biliares/biossíntese , Ácidos e Sais Biliares/sangue , Artérias Carótidas/fisiologia , Ceco/microbiologia , Suplementos Nutricionais , Modelos Animais de Doenças , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-3/deficiência , Expressão Gênica/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/biossíntese , Masculino , Artérias Mesentéricas/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Neurotensina/genética , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Proglucagon/genética , Simportadores/genética , Vasodilatação
10.
Metab Brain Dis ; 33(1): 63-77, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29034440

RESUMO

Antipsychotics, such as risperidone, increase food intake and induce alteration in glucose and lipid metabolism concomitantly with overweight and body fat increase, these biological abnormalities belong to the metabolic syndrome definition (high visceral adiposity, hypertriglyceridemia, hyperglycemia, low HDL-cholesterol and high blood pressure). Curcumin is a major component of traditional turmeric (Curcuma longa) which has been reported to improve lipid and glucose metabolism and to decrease weight in obese mice. We questioned the potential capacity of curcumin, contained in Curcuma longa extract (Biocurcuma™), to attenuate the risperidone-induced metabolic dysfunction. Two groups of mice were treated once a week, for 22 weeks, with intraperitoneal injection of risperidone (Risperdal) at a dose 12.5 mpk. Two other groups received intraperitoneal injection of the vehicle of Risperdal following the same schedule. Mice of one risperidone-treated groups and of one of vehicle-treated groups were fed a diet with 0.05% Biocurcuma™ (curcumin), while mice of the two other groups received the standard diet. Curcumin limited the capacity of risperidone to reduce spontaneous motricity, but failed to impede risperidone-induced increase in food intake. Curcumin did not reduce the capacity of risperidone to induce weight gain, but decreased visceral adiposity and decreased the risperidone-induced hepatomegaly, but not steatosis. Furthermore, curcumin repressed the capacity of risperidone to induce the hepatic over expression of enzymes involved in lipid metabolism (LXRα, FAS, ACC1, LPL, PPARγ, ACO, SREBP2) and decreased risperidone-induced glucose intolerance and hypertriglyceridemia. Curcumin decreased risperidone-induced increases in serum markers of hepatotoxicity (ALAT, ASAT), as well as of one major hepatic pro-inflammatory transcription factor (NFκB: p105 mRNA and p65 protein). These findings support that nutritional doses of curcumin contained in Curcuma longa extract are able to partially counteract the risperidone-induced metabolic dysfunction in mice, suggesting that curcumin ought to be tested to reduce the capacity of risperidone to induce the metabolic syndrome in human.


Assuntos
Curcuma/efeitos dos fármacos , Curcumina/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Risperidona/farmacologia , Animais , Glicemia/metabolismo , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/metabolismo , Feminino , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos
11.
Free Radic Biol Med ; 103: 146-154, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27988338

RESUMO

Whereas the anti-inflammatory properties and mechanisms of action of long chain ω3 PUFAs have been abundantly investigated, research gaps remain regarding the respective contribution and mechanisms of action of their oxygenated metabolites collectively known as oxylipins. We conducted a dose-dependent and comparative study in human primary macrophages aiming to compare the anti-inflammatory activity of two types of DHA-derived oxylipins including the well-described protectins (NPD1 and PDX), formed through lipoxygenase pathway and the neuroprostanes (14-A4t- and 4-F4t-NeuroP) formed through free-radical mediated oxygenation and expected to be new anti-inflammatory mediators. Considering the potential ability of these DHA-derived oxylipins to bind PPARs and knowing the central role of these transcription factors in the regulation of macrophage inflammatory response, we performed transactivation assays to compare the ability of protectins and neuroprostanes to activate PPARs. All molecules significantly reduced mRNA levels of cytokines such as IL-6 and TNF-α, however not at the same doses. NPD1 showed the most effect at 0.1µM (-14.9%, p<0.05 for IL-6 and -26.7%, p<0.05 for TNF-α) while the three other molecules had greater effects at 10µM, with the strongest result due to the cyclopentenone neuroprostane, 14-A4t-NeuroP (-49.8%, p<0.001 and -40.8%, p<0.001, respectively). Part of the anti-inflammatory properties of the DHA-derived oxylipins investigated could be linked to their activation of PPARs. Indeed, all tested oxylipins significantly activated PPARγ, with 14-A4t-NeuroP leading to the strongest activation, and NPD1 and PDX also activated PPARα. In conclusion, our results show that neuroprostanes and more especially cyclopentenone neuroprostanes have potent anti-inflammatory activities similar or even more pronounced than protectins supporting that neuroprostanes should be considered as important contributors to the anti-inflammatory effects of DHA.


Assuntos
Anti-Inflamatórios/farmacologia , Ácidos Docosa-Hexaenoicos/farmacologia , Macrófagos/imunologia , Neuroprostanos/farmacologia , Oxilipinas/farmacologia , Animais , Células COS , Células Cultivadas , Chlorocebus aethiops , Citocinas/genética , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Expressão Gênica/efeitos dos fármacos , Humanos , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo
12.
Nat Commun ; 6: 8250, 2015 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-26394692

RESUMO

Insulin-degrading enzyme (IDE) is a protease that cleaves insulin and other bioactive peptides such as amyloid-ß. Knockout and genetic studies have linked IDE to Alzheimer's disease and type-2 diabetes. As the major insulin-degrading protease, IDE is a candidate drug target in diabetes. Here we have used kinetic target-guided synthesis to design the first catalytic site inhibitor of IDE suitable for in vivo studies (BDM44768). Crystallographic and small angle X-ray scattering analyses show that it locks IDE in a closed conformation. Among a panel of metalloproteases, BDM44768 selectively inhibits IDE. Acute treatment of mice with BDM44768 increases insulin signalling and surprisingly impairs glucose tolerance in an IDE-dependent manner. These results confirm that IDE is involved in pathways that modulate short-term glucose homeostasis, but casts doubt on the general usefulness of the inhibition of IDE catalytic activity to treat diabetes.


Assuntos
Ácidos Hidroxâmicos/síntese química , Insulisina/antagonistas & inibidores , Triazóis/síntese química , Animais , Células CACO-2 , Domínio Catalítico , Diabetes Mellitus/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos , Teste de Tolerância a Glucose , Humanos , Ácidos Hidroxâmicos/farmacologia , Ácidos Hidroxâmicos/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microssomos Hepáticos , Terapia de Alvo Molecular , Distribuição Aleatória , Relação Estrutura-Atividade , Triazóis/farmacologia , Triazóis/uso terapêutico
13.
Mol Endocrinol ; 29(8): 1134-43, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26087172

RESUMO

Acute liver failure (ALF) is a severe and rapid liver injury, often occurring without any preexisting liver disease, which may precipitate multiorgan failure and death. ALF is often associated with impaired ß-oxidation and increased oxidative stress (OS), characterized by elevated levels of hepatic reactive oxygen species (ROS) and lipid peroxidation (LPO) products. Peroxisome proliferator-activated receptor (PPAR)α has been shown to confer hepatoprotection in acute and chronic liver injury, at least in part, related to its ability to control peroxisomal and mitochondrial ß-oxidation. To study the pathophysiological role of PPARα in hepatic response to high OS, we induced a pronounced LPO by treating wild-type and Pparα-deficient mice with high doses of fish oil (FO), containing n-3 polyunsaturated fatty acids. FO feeding of Pparα-deficient mice, in contrast to control sunflower oil, surprisingly induced coma and death due to ALF as indicated by elevated serum alanine aminotransferase, aspartate aminotransferase, ammonia, and a liver-specific increase of ROS and LPO-derived malondialdehyde. Reconstitution of PPARα specifically in the liver using adeno-associated serotype 8 virus-PPARα in Pparα-deficient mice restored ß-oxidation and ketogenesis and protected mice from FO-induced lipotoxicity and death. Interestingly, administration of the ketone body ß-hydroxybutyrate prevented FO-induced ALF in Pparα-deficient mice, and normalized liver ROS and malondialdehyde levels. Therefore, PPARα protects the liver from FO-induced OS through its regulatory actions on ketone body levels. ß-Hydroxybutyrate treatment could thus be an option to prevent LPO-induced liver damage.


Assuntos
Fígado Gorduroso/metabolismo , Corpos Cetônicos/química , Falência Hepática Aguda/metabolismo , PPAR alfa/deficiência , PPAR alfa/metabolismo , Ácido 3-Hidroxibutírico/química , Animais , Ácidos Graxos/metabolismo , Fígado Gorduroso/prevenção & controle , Feminino , Peroxidação de Lipídeos , Fígado/metabolismo , Falência Hepática Aguda/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Oxirredução , Estresse Oxidativo , Peroxissomos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Triglicerídeos/metabolismo
14.
Handb Exp Pharmacol ; 224: 617-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25523004

RESUMO

Dyslipidaemia is a major risk factor for cardiovascular diseases. Pharmacological lowering of LDL-C levels using statins reduces cardiovascular risk. However, a substantial residual risk persists especially in patients with type 2 diabetes mellitus. Because of the inverse association observed in epidemiological studies of HDL-C with the risk for cardiovascular diseases, novel therapeutic strategies to raise HDL-C levels or improve HDL functionality are developed as complementary therapy for cardiovascular diseases. However, until now most therapies targeting HDL-C levels failed in clinical trials because of side effects or absence of clinical benefits. This chapter will highlight the emerging small molecules currently developed and tested in clinical trials to pharmacologically modulate HDL-C and functionality including new CETP inhibitors (anacetrapib, evacetrapib), novel PPAR agonists (K-877, CER-002, DSP-8658, INT131 and GFT505), LXR agonists (ATI-111, LXR-623, XL-652) and RVX-208.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Desenho de Fármacos , Dislipidemias/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Animais , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/metabolismo , Proteínas de Transferência de Ésteres de Colesterol/antagonistas & inibidores , Proteínas de Transferência de Ésteres de Colesterol/metabolismo , Dislipidemias/complicações , Dislipidemias/metabolismo , Humanos , Hipolipemiantes/química , Receptores X do Fígado , Terapia de Alvo Molecular , Receptores Nucleares Órfãos/agonistas , Receptores Nucleares Órfãos/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/agonistas , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Quinazolinas/uso terapêutico , Quinazolinonas , Transdução de Sinais/efeitos dos fármacos
15.
Diab Vasc Dis Res ; 11(6): 440-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25212694

RESUMO

We report here the efficacy and safety of GFT505, a novel liver-targeted peroxisome proliferator-activated receptor alpha/delta (PPARα/δ) agonist, in the db/db mouse model of diabetes. Mice were treated with vehicle, GFT505, PPARγ agonist rosiglitazone or dual-PPARα/γ agonist aleglitazar for up to 8 weeks. All compounds comparably reduced fasting glycaemia and HbA1c and improved insulin sensitivity. The glucose-lowering effect of GFT505 was associated with decreased hepatic gluconeogenesis, correlating with reduced expression of gluconeogenic genes. In contrast with the PPARγ-activating drugs, treatment with GFT505 did not affect heart weight and did not increase plasma adiponectin concentrations. This absence of cardiac effects of GFT505 was confirmed after 12 months of administration in cynomolgus monkeys, by the absence of echocardiographic and histological findings. Moreover, long-term GFT505 administration to monkeys induced no change in haematological parameters or in bone marrow differential cell counts. Compared to PPARγ-activating drugs, the dual-PPARα/δ agonist GFT505 therefore shows an improved benefit/risk ratio, treating multiple features of type 2 diabetes without inducing the cardiac side-effects associated with PPARγ activation.


Assuntos
Chalconas/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Propionatos/uso terapêutico , Animais , Glicemia/efeitos dos fármacos , Chalconas/farmacologia , Diabetes Mellitus Experimental/sangue , Avaliação Pré-Clínica de Medicamentos , Lipídeos/sangue , Masculino , Camundongos , PPAR alfa/agonistas , PPAR delta/agonistas , Propionatos/farmacologia , Distribuição Aleatória
16.
Neurobiol Dis ; 43(2): 486-94, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21569847

RESUMO

Tau pathology is encountered in many neurodegenerative disorders known as tauopathies, including Alzheimer's disease. Physical activity is a lifestyle factor affecting processes crucial for memory and synaptic plasticity. Whether long-term voluntary exercise has an impact on Tau pathology and its pathophysiological consequences is currently unknown. To address this question, we investigated the effects of long-term voluntary exercise in the THY-Tau22 transgenic model of Alzheimer's disease-like Tau pathology, characterized by the progressive development of Tau pathology, cholinergic alterations and subsequent memory impairments. Three-month-old THY-Tau22 mice and wild-type littermates were assigned to standard housing or housing supplemented with a running wheel. After 9 months of exercise, mice were evaluated for memory performance and examined for hippocampal Tau pathology, cholinergic defects, inflammation and genes related to cholesterol metabolism. Exercise prevented memory alterations in THY-Tau22 mice. This was accompanied by a decrease in hippocampal Tau pathology and a prevention of the loss of expression of choline acetyltransferase within the medial septum. Whereas the expression of most cholesterol-related genes remained unchanged in the hippocampus of running THY-Tau22 mice, we observed a significant upregulation in mRNA levels of NPC1 and NPC2, genes involved in cholesterol trafficking from the lysosomes. Our data support the view that long-term voluntary physical exercise is an effective strategy capable of mitigating Tau pathology and its pathophysiological consequences.


Assuntos
Doença de Alzheimer/patologia , Doença de Alzheimer/terapia , Terapia por Exercício/métodos , Condicionamento Físico Animal/fisiologia , Proteínas tau/genética , Doença de Alzheimer/fisiopatologia , Animais , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas tau/efeitos adversos , Proteínas tau/antagonistas & inibidores
17.
Phytother Res ; 23(6): 892-5, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19107738

RESUMO

Microdesmis keayana (Pandaceae) is an African tropical plant whose roots are used in traditional medicine for erection impairment but the compounds responsible for its action are unknown. Two major alkaloids recently isolated from the roots of M. keayana, keayanidine B and keayanine, were tested for vasorelaxing properties using isolated rat aortic rings precontracted by phenylephrine to confirm its traditional use. Influence of the alkaloids on the endothelial production of endothelial nitric oxide synthase (eNOS) was measured by quantitative polymerase chain reaction (QPCR) analysis. Scavenging activities were assessed versus 1,1-diphenyl-2-picrylhydrazyle (DPPH) and reactive oxygen species (ROS) such as superoxide anion (O(2)(*-) and hydrogen peroxide (H(2)O(2)) in cell-free and cellular systems. The results showed that keayanidine B and keayanine had significant vasorelaxing properties. This effect could be due to their strong antioxidant activity versus O(2)(*-) and H(2)O(2) and to their stimulation of eNOS mRNA expression. Therefore these alkaloids could indirectly stimulate NO production in the vascular bed and would explain the traditional use of M. keayana in erectile dysfunction.


Assuntos
Alcaloides/farmacologia , Ácidos Cumáricos/farmacologia , Disfunção Erétil/tratamento farmacológico , Extratos Vegetais/farmacologia , Espermidina/análogos & derivados , Animais , Antioxidantes/farmacologia , Aorta/efeitos dos fármacos , Bovinos , Células Cultivadas , Peróxido de Hidrogênio/metabolismo , Magnoliopsida/química , Masculino , Estrutura Molecular , Óxido Nítrico Sintase Tipo III/metabolismo , Ratos , Espermidina/farmacologia , Superóxidos/metabolismo , Vasodilatação/efeitos dos fármacos
18.
Am J Cardiol ; 102(10 Suppl): 1K-34K, 2008 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-19068318

RESUMO

Despite achieving targets for low-density lipoprotein (LDL) cholesterol, blood pressure, and glycemia in accordance with current standards of care, patients with dyslipidemia remain at high residual risk of vascular events. Atherogenic dyslipidemia, characterized by elevated triglycerides and low levels of high-density lipoprotein (HDL) cholesterol, often with elevated apolipoprotein B and non-HDL cholesterol, is common in patients with established cardiovascular disease (CVD), type 2 diabetes mellitus, or metabolic syndrome and contributes to both macrovascular and microvascular residual risk. However, atherogenic dyslipidemia is largely underdiagnosed and undertreated in clinical practice. The Residual Risk Reduction Initiative (R3i) was established to address this highly relevant clinical issue. The aims of this position paper are (1) to highlight evidence that atherogenic dyslipidemia is associated with residual macrovascular and microvascular risk in patients at high risk for CVD, despite current standards of care for dyslipidemia and diabetes; and (2) to recommend therapeutic intervention for reducing this residual vascular risk supported by evidence and expert consensus. Lifestyle modification with nutrition and exercise is an important, effective, and underutilized first step in reducing residual vascular risk. Therapeutic intervention aimed at achievement of all lipid targets is also often required. Combination lipid-modifying therapy, with the addition of niacin, a fibrate, or omega-3 fatty acids to statin therapy, increases the probability of achieving all lipid goals. Outcomes studies are in progress to evaluate whether these combination treatment strategies translate to a clinical benefit greater than that achieved with statins alone. The R3i highlights the need to address with lifestyle and/or pharmacotherapy the high level of residual risk of CVD events and microvascular complications among patients with dyslipidemia receiving therapy for high levels of LDL cholesterol and for diabetes in accordance with current standards of care.


Assuntos
Dislipidemias/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Lipídeos/sangue , Doenças Vasculares/prevenção & controle , Dislipidemias/sangue , Dislipidemias/complicações , Saúde Global , Humanos , Incidência , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Doenças Vasculares/epidemiologia , Doenças Vasculares/etiologia
19.
Diab Vasc Dis Res ; 5(4): 319-35, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18958843

RESUMO

Despite current standards of care aimed at achieving targets for low-density lipoprotein (LDL) cholesterol, blood pressure and glycaemia, dyslipidaemic patients remain at high residual risk of vascular events. Atherogenic dyslipidaemia, specifically elevated triglycerides and low levels of high-density lipoprotein (HDL) cholesterol, often with elevated apolipoprotein B and non-HDL cholesterol, is common in patients with established cardiovascular disease, type 2 diabetes, obesity or metabolic syndrome and is associated with macrovascular and microvascular residual risk. The Residual Risk Reduction Initiative (R3I) was established to address this important issue. This position paper aims to highlight evidence that atherogenic dyslipidaemia contributes to residual macrovascular risk and microvascular complications despite current standards of care for dyslipidaemia and diabetes, and to recommend therapeutic intervention for reducing this, supported by evidence and expert consensus. Lifestyle modification is an important first step. Additionally, pharmacotherapy is often required. Adding niacin, a fibrate or omega-3 fatty acids to statin therapy improves achievement of all lipid risk factors. Outcomes studies are evaluating whether these strategies translate to greater clinical benefit than statin therapy alone. In conclusion, the R3I highlights the need to address with lifestyle and/or pharmacotherapy the high level of residual vascular risk among dyslipidaemic patients who are treated in accordance with current standards of care.


Assuntos
Aterosclerose/terapia , Doenças Cardiovasculares/prevenção & controle , Dislipidemias/terapia , Hipolipemiantes/uso terapêutico , Comportamento de Redução do Risco , Aterosclerose/etiologia , Aterosclerose/fisiopatologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/fisiopatologia , Terapia Combinada , Dislipidemias/complicações , Dislipidemias/fisiopatologia , Medicina Baseada em Evidências , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde , Humanos , Microcirculação , Guias de Prática Clínica como Assunto , Resultado do Tratamento
20.
J Ethnopharmacol ; 116(1): 112-9, 2008 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-18164568

RESUMO

AIMS OF THE STUDY: Caesalpinia benthamiana (=Mezoneuron benthamianum) (Fabaceae) is an African tropical plant whose roots are used in traditional medicine as an aqueous decoction for many purposes, especially for erection impairment but its action mechanism is unknown. The action of Caesalpinia benthamiana on sexual behaviour and some assays on potential modes of action were performed. MATERIALS AND METHODS: The aqueous extract of Caesalpinia benthamiana (AECB) was tested for vasorelaxing properties using isolated rat aortic rings precontracted by phenylephrine. Influence of AECB in the production of endothelial isoform of nitric oxide synthase (eNOS) was measured by quantitative polymerase chain reaction (QPCR) analysis. Scavenging activities versus reactive oxygen species (ROS), such as superoxide anion (O(2).(-)), hydrogen peroxide (H(2)O(2)), and hypochlorous acid (HOCl) were assessed. Action of AECB on the cellular generation of O(2).(-) was also tested in a physiopathology model of oxidative burst using human polymorphonuclear neutrophils stimulated by phorbol myristate acetate. The aphrodisiac properties of AECB administered orally by gavage (50 mg/kg body weight) to male rats were evaluated by observing the sexual behaviour of animals. Finally, a short-term toxicity study was undertaken to establish the therapeutic index of AECB administered orally to rats at high dose (2 g/kg body weight). RESULTS: C. benthamiana roots are rich in phenolic compounds (gallic acid, resveratrol and tannins). The results showed that AECB had significant vasorelaxing properties. The extract also had a strong radical activity against ROS in cell-free and cellular systems and stimulated eNOS mRNA expression. As for the aphrodisiac activity of AECB in male rats, results have shown that sexual parameters are stimulated. Furthermore, after oral administration at high dose, AECB causes no mortality or changes in rats' behaviour. CONCLUSION: AECB enhanced the sexual activity of male rats. This could be partly explained by its vasorelaxant properties, which may be caused by an increase in NO production in vascular bed and a decrease in its destruction.


Assuntos
Antioxidantes/farmacologia , Afrodisíacos/farmacologia , Caesalpinia , Extratos Vegetais/farmacologia , Vasoconstrição/efeitos dos fármacos , Animais , Caesalpinia/química , Bovinos , Células Cultivadas , Feminino , Humanos , Masculino , NADP/metabolismo , Raízes de Plantas/química , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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