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1.
Mol Nutr Food Res ; 67(7): e2200589, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36726048

RESUMO

SCOPE: Long-term high-fat diet (HFD) causes insulin resistance, which is a primary etiological factor in the development of obesity and type 2 diabetes mellitus. Impaired insulin clearance is not only a consequence but also a cause of insulin resistance. The kidney is a major site of insulin clearance, where the insulin-degrading enzyme (IDE) plays a vital role in the proximal tubule. Thus, the study investigates the role of renal IDE in the regulation of insulin resistance in HFD-induced obese mice. METHODS AND RESULTS: Twenty four-weeks of HFD in C57BL/6 mice causes insulin resistance and impaires insulin clearance, accompanied by a decrease in renal IDE expression and activity. Palmitic acid decreases IDE mRNA and protein expressions in HK-2 cells. RNA-Seq analysis found that the PPAR pathway is involved. 24-weeks of HFD decreases renal PPARγ, but not PPARα or PPARß/δ mRNA expression. The inhibition of IDE expression by palmitic acid is prevented by the PPARγ agonist rosiglitazone. The amount of PPARγ bound to the promoters of IDE is decreased in palmitic acid-treated cells. Rosiglitazone improves insulin clearance and insulin resistance and increases renal IDE expression in HFD fed-mice. CONCLUSION: Long-term HFD decreases renal IDE expression and activity, and causes insulin resistance, which involves PPARγ.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Insulisina , Camundongos , Animais , PPAR gama/genética , PPAR gama/metabolismo , Rosiglitazona , Dieta Hiperlipídica/efeitos adversos , Resistência à Insulina/fisiologia , Insulisina/genética , Insulisina/metabolismo , Diabetes Mellitus Tipo 2/etiologia , Ácido Palmítico/farmacologia , Camundongos Endogâmicos C57BL , Insulina/metabolismo , Rim/metabolismo , Camundongos Obesos , RNA Mensageiro/metabolismo
2.
Lipids Health Dis ; 22(1): 6, 2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36641489

RESUMO

BACKGROUND: Curcumin (Cur) is a bioactive dietary polyphenol of turmeric with various biological activities against several cancers. Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths. Intestinal cholesterol homeostasis is associated with CRC. Chemotherapy for CRC is related to varied adverse effects. Therefore, natural products with anti-cancer properties represent a potential strategy for primary prevention of CRC. METHODS: The present study used Cur as a therapeutic approach against CRC using the Caco-2 cell line. The cells were treated with different concentrations of Cur for different duration of time and then the proliferation ability of cells was assessed using Cell Counting Kit-8 and 5-Ethynyl-2'-deoxyuridine assays. Oil red O staining and cholesterol assay kit were used to evaluate cellular lipid content and cholesterol outward transportation. Finally, the protein expressions of cholesterol transport-related protein and signal transduction molecules were assessed using Western blot assay. RESULTS: Cur inhibited cell proliferation in Caco-2 cells in a dose- and time-dependent manner by activating the transient receptor potential cation channel subfamily A member 1 (TRPA1) channel. Activation of the TRPA1 channel led to increased intracellular calcium, peroxisome proliferator-activated receptor gamma (PPARγ) upregulation, and the subsequent downregulation of the specificity protein-1 (SP-1)/sterol regulatory element-binding protein-2 (SREBP-2)/Niemann-Pick C1-like 1 (NPC1L1) signaling pathway-related proteins, and finally reduced cholesterol absorption in Caco-2 cells. CONCLUSIONS: Cur inhibits cell proliferation and reduces cholesterol absorption in Caco-2 cells through the Ca2+/PPARγ/SP-1/SREBP-2/NPC1L1 signaling by activating the TRPA1 channel, suggesting that Cur can be used as a dietary supplement for the primary prevention of CRC. In Caco-2 cells, Cur first stimulates calcium influx by activating the TRPA1 channel, further upregulates PPARγ and downregulates SP-1/SREBP-2/NPC1L1 signaling pathway, and finally inhibits the absorption of cholesterol. TRPA1, transient receptor potential cation channel subfamily A member 1; NPC1L1, Niemann-Pick C1-like 1; PPARγ, peroxisome proliferator-activated receptor gamma; SP-1, specificity protein-1; SREBP-2, sterol regulatory element-binding protein-2; Cur, curcumin.


Assuntos
Curcumina , Proteínas de Membrana Transportadoras , Humanos , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Membrana/metabolismo , Células CACO-2 , Curcumina/farmacologia , Canal de Cátion TRPA1/genética , Canal de Cátion TRPA1/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Cálcio/metabolismo , Colesterol/metabolismo , Proliferação de Células , Absorção Intestinal
3.
J Clin Res Pediatr Endocrinol ; 15(4): 438-443, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-35633639

RESUMO

Neurofibromatosis-Noonan syndrome (NFNS), a rare autosomal-dominant hereditary disease, is characterized by clinical manifestations of both neurofibromatosis type 1 (NF1) and NS. We present a case of NFNS with short stature caused by a heterozygous nonsense variant of the NF1 gene. A 12-year-old boy was admitted because of short stature, numerous café-au-lait spots, low-set and posteriorly rotated ears, sparse eyebrows, broad forehead, and inverted triangular face. Cranial and spinal magnetic resonance imaging showed abnormal nodular lesions. Molecular analysis revealed a novel heterozygous c.6189 C > G (p.(Tyr2063*)) variant in the NF1 gene. The patient was not prescribed recombinant growth hormone (GH) therapy because exogenous GH may have enlarged the abnormal skeletal lesions. During follow-up, Lisch nodules were found in the ophthalmologic examination. NFNS, a variant form of NF1, is caused by heterozygous mutations in the NF1 gene. The mechanism of GH deficiency caused by NF1 is still unclear. Whether NFNS patients should be treated with exogenous GH remains controversial.


Assuntos
Nanismo Hipofisário , Neurofibromatoses , Neurofibromatose 1 , Masculino , Humanos , Criança , Neurofibromatose 1/complicações , Neurofibromatose 1/genética , Neurofibromatose 1/diagnóstico , Neurofibromatoses/diagnóstico , Hormônio do Crescimento
4.
Artigo em Inglês | MEDLINE | ID: mdl-36479179

RESUMO

Abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) are essential for the development of hypertension. Insulin has been identified to promote VSMC proliferation and migration; resveratrol has been shown to have protective effects against cardiovascular diseases. This study aimed to investigate the effect of resveratrol on insulin-induced VSMC proliferation and migration and its potential mechanism. VSMC proliferation was measured by Cell Counting Kit-8 (CCK-8), cell counting method, and 5-ethynyl-2'-deoxyuridine (EdU) incorporation assay. Cell migration was detected by wound healing assay and transwell method. Expression of silent information regulator of transcription 1 (SIRT1) and phosphorylation levels of signaling molecules, such as phosphatidylinositol 3-kinase (PI3K) and protein kinase B (Akt), in VSMCs were detected by Western blotting. Resveratrol (25-150 µM) was found to inhibit insulin-induced VSMC proliferation. Pretreatment with 100 µM resveratrol reduced insulin (100 nM)-mediated VSMC migration. LY294002, an inhibitor of PI3K, inhibited the stimulatory effect of insulin (100 nM) on the proliferation of VSMCs. Treatment with resveratrol also decreased insulin-induced stimulatory effect on PI3K and Akt phosphorylation levels. Moreover, resveratrol treatment increased SIRT1 protein expression in VSMCs. A SIRT1 inhibitor, EX527, reversed the inhibitory effect of resveratrol on insulin-induced VSMC proliferation and migration and activation of PI3K and Akt phosphorylation levels. In conclusion, our study revealed that treatment with resveratrol inhibited insulin-mediated VSMC proliferation and migration, possibly by activating SIRT1 and downregulating the PI3K/AKT pathway.

5.
Cardiovasc Diabetol ; 14: 22, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25849380

RESUMO

BACKGROUND: The prevalence of obesity has dramatically increased worldwide and has attracted rising attention, but the mechanism is still unclear. Previous studies revealed that transient receptor potential vanilloid 1 (TRPV1) channels take part in weight loss by enhancing intracellular Ca2+ levels. However, the potential mechanism of the effect of dietary capsaicin on obesity is not completely understood. Ca2+ transfer induced by connexin43 (Cx43) molecules between coupled cells takes part in adipocyte differentiation. Whether TRPV1-evoked alterations in Cx43-mediated adipocyte-to-adipocyte communication play a role in obesity is unknown. MATERIALS AND METHODS: We investigated whether Cx43 participated in TRPV1-mediated adipocyte lipolysis in cultured 3T3-L1 preadipocytes and visceral adipose tissues from humans and wild-type (WT) and TRPV1-deficient (TRPV1-/-) mice. RESULTS: TRPV1 and Cx43 co-expressed in mesenteric adipose tissue. TRPV1 activation by capsaicin increased the influx of Ca2+ in 3T3-L1 preadipocytes and promoted cell lipolysis, as shown by Oil-red O staining. These effects were deficient when capsazepine, a TRPV1 antagonist, and 18 alpha-glycyrrhetinic acid (18α-GA), a gap-junction inhibitor, were administered. Long-term chronic dietary capsaicin reduced the weights of perirenal, mesenteric and testicular adipose tissues in WT mice fed a high-fat diet. Capsaicin increased the expression levels of p-CaM, Cx43, CaMKII, PPARδ and HSL in mesenteric adipose tissues from WT mice fed a high-fat diet, db/db mice, as well as obese humans, but these effects of capsaicin were absent in TRPV1-/- mice. Long-term chronic dietary capsaicin decreased the body weights and serum lipids of WT mice, but not TRPV1-/- mice, fed a high-fat diet. CONCLUSION: This study demonstrated that capsaicin activation of TRPV1-evoked increased Ca2+ influx in Cx43-mediated adipocyte-to-adipocyte communication promotes lipolysis in both vitro and vivo. TRPV1 activation by dietary capsaicin improves visceral fat remodeling through the up-regulation of Cx43.


Assuntos
Cálcio/metabolismo , Capsaicina/administração & dosagem , Conexina 43/metabolismo , Gordura Intra-Abdominal/efeitos dos fármacos , Gordura Intra-Abdominal/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Células Cultivadas , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
6.
Diabetes Metab Res Rev ; 30(6): 505-12, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24700718

RESUMO

BACKGROUND: Metabolic syndrome has received great attention because it poses a potential cardiovascular hazard, which increases the risk of lower extremity atherosclerosis. However, the relationship between the components of metabolic syndrome and the onset of chronic venous disorder of the lower extremities remains unexplained. METHODS: This study investigated the characteristics of cardiometabolic risk factors of early chronic venous disorder of the lower extremities in subjects with cardiometabolic risk. The characteristics of risk factors and diabetes-related complications in diabetic patients with early chronic venous disorder of the lower extremities were also investigated. In addition, the association between early chronic venous disorder and atherosclerosis of the lower extremities was analysed. The study examined 782 subjects with cardiometabolic risk factors, including obesity, hypertension, diabetes mellitus and dyslipidaemia. Lower extremity venous function was measured by digital photoplethysmography. RESULTS: Women had a higher prevalence of early chronic venous disorder than did men (p < 0.01). Male subjects with early chronic venous disorder had a higher systolic blood pressure than those with normal venous function (p < 0.01), and female subjects with early chronic venous disorder had a higher fasting plasma glucose level than did controls (p < 0.05). The prevalence of diabetes mellitus is also significantly higher in female patients with early chronic venous disorder (p = 0.000). Diabetic patients with early chronic venous disorder not only had higher fasting plasma glucose and total cholesterol levels but also had more serious macrovascular complications than the control group. The independent risk factors of early chronic venous disorder in female subjects with cardiometabolic risks were age and fasting plasma glucose in men it was only age Women face a two times greater risk than men. The independent risk factors of early chronic venous disorder in diabetic patients were age, gender, HbA1c and triglyceride levels Women had an almost 12 times greater risk of early chronic venous disorder than men. Among the diabetic patients, the prevalence of early chronic venous disorder did not differ by ankle-brachial index. CONCLUSION: Female subjects with cardiometabolic risk factors or female diabetic patients face a greater risk of early chronic venous disorder than do male subjects. Diabetic patients with early chronic venous disorder had more serious macrovascular complications than did the controls, and the early venous function was found to be correlated with the blood glucose level and triglyceride status.


Assuntos
Envelhecimento , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/epidemiologia , Síndrome Metabólica/epidemiologia , Doenças Vasculares/epidemiologia , Fatores Etários , Idoso , Aterosclerose/complicações , Aterosclerose/epidemiologia , Aterosclerose/prevenção & controle , Índice de Massa Corporal , China/epidemiologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/terapia , Angiopatias Diabéticas/complicações , Angiopatias Diabéticas/prevenção & controle , Dislipidemias/complicações , Dislipidemias/epidemiologia , Feminino , Hemoglobinas Glicadas/análise , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Incidência , Extremidade Inferior , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Obesidade Abdominal/complicações , Obesidade Abdominal/epidemiologia , Prevalência , Fatores de Risco , Fatores Sexuais , Doenças Vasculares/complicações , Doenças Vasculares/prevenção & controle
7.
Obesity (Silver Spring) ; 21(3): 538-45, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23592661

RESUMO

OBJECTIVE: Obesity is a prominent component of metabolic syndrome and a major risk factor for renal disease. The aim of this study was to explore the effect of cross-talk between peroxisome proliferator-activated receptor (PPAR)δ and p38 mitogen-activated protein kinase (p38 MAPK) on obesity-related glomerulopathy. DESIGN AND METHODS: Male Wistar rats were randomly assigned to standard laboratory chow or a high-fat diet for 32 weeks. Glomerular mesangial cells HBZY-1 and mature differentiation 3T3-L1 cells were cocultured and were transfected with PPARδ-expressing vectors or treated with agonist or inhibitor of PPARδ or p38 MAPK. RESULTS: Rats on a high-fat diet showed typical characteristics of metabolic syndrome including obesity, dyslipidemia, insulin resistance, and hypertension. Rats on a high-fat diet also had significant glomerular hypertrophy and extracellular matrix accumulation, which were accompanied by increased p38 MAPK phosphorylation and decreased PPARδ expression in the kidney tissue. The roles of p38 MAPK and PPARδ in a coculture system of mesangial cells and mature differentiation 3T3-L1 cells were further explored. PPARδ suppression promoted laminin and type IV collagen secretion through p38 MAPK phosphorylation in mesangial cells, whereas PPARδ overexpression or PPARδ agonist attenuated phosphorylation of p38 MAPK and laminin and type IV collagen secretion. CONCLUSIONS: The characteristics of obesity-related glomerulopathy, which might be partly caused by PPARδ suppression-induced p38 MAPK activation and laminin and type IV collagen secretion was demonstrated.


Assuntos
Nefropatias/patologia , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Obesidade/fisiopatologia , PPAR delta/metabolismo , Células 3T3-L1 , Animais , Western Blotting , Diferenciação Celular , Colágeno/antagonistas & inibidores , Colágeno/metabolismo , Dieta Hiperlipídica , Mesângio Glomerular/citologia , Mesângio Glomerular/patologia , Imuno-Histoquímica , Rim/metabolismo , Rim/patologia , Nefropatias/etiologia , Laminina/antagonistas & inibidores , Laminina/metabolismo , Sistema de Sinalização das MAP Quinases , Masculino , Células Mesangiais/metabolismo , Células Mesangiais/patologia , Síndrome Metabólica/complicações , Síndrome Metabólica/fisiopatologia , Camundongos , Proteína Quinase 14 Ativada por Mitógeno/genética , Obesidade/complicações , PPAR delta/genética , Fosforilação , Ratos , Ratos Wistar
8.
Diabetes ; 61(8): 2155-65, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22664955

RESUMO

Type 2 diabetes mellitus (T2DM) is rapidly prevailing as a serious global health problem. Current treatments for T2DM may cause side effects, thus highlighting the need for newer and safer therapies. We tested the hypothesis that dietary capsaicin regulates glucose homeostasis through the activation of transient receptor potential vanilloid 1 (TRPV1)-mediated glucagon-like peptide-1 (GLP-1) secretion in the intestinal cells and tissues. Wild-type (WT) and TRPV1 knockout (TRPV1(-/-)) mice were fed dietary capsaicin for 24 weeks. TRPV1 was localized in secretin tumor cell-1 (STC-1) cells and ileum. Capsaicin stimulated GLP-1 secretion from STC-1 cells in a calcium-dependent manner through TRPV1 activation. Acute capsaicin administration by gastric gavage increased GLP-1 and insulin secretion in vivo in WT but not in TRPV1(-/-) mice. Furthermore, chronic dietary capsaicin not only improved glucose tolerance and increased insulin levels but also lowered daily blood glucose profiles and increased plasma GLP-1 levels in WT mice. However, this effect was absent in TRPV1(-/-) mice. In db/db mice, TRPV1 activation by dietary capsaicin ameliorated abnormal glucose homeostasis and increased GLP-1 levels in the plasma and ileum. The present findings suggest that TRPV1 activation-stimulated GLP-1 secretion could be a promising approach for the intervention of diabetes.


Assuntos
Glicemia/metabolismo , Capsaicina/farmacologia , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Canais de Cátion TRPV/fisiologia , Animais , Glicemia/efeitos dos fármacos , Células Enteroendócrinas/metabolismo , Peptídeo 1 Semelhante ao Glucagon/sangue , Teste de Tolerância a Glucose , Homeostase/efeitos dos fármacos , Íleo/metabolismo , Insulina/metabolismo , Secreção de Insulina , Camundongos
9.
J Hypertens ; 30(7): 1430-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22525206

RESUMO

OBJECTIVES: Obesity and hypertension are associated with an adverse metabolic profile and systemic low-grade inflammation. Metformin reduces weight and inflammation in patients with diabetes, but it is unclear whether it has beneficial effects in patients without diabetes. The objective was to explore whether metformin-based treatment could benefit obesity-related hypertension without diabetes. METHODS: A randomized, double-blind, placebo-controlled factorial trial was conducted in 360 obese hypertensive patients without diabetes in Chongqing, China. After a 1-2-week run-in period, patients were randomly assigned to metformin (500 mg once per day) or placebo, as well as to an antihypertensive medication. Change in blood pressure, obesity measurements and metabolic profile were assessed at 24 weeks. RESULTS: The 180 participants randomized to metformin and 180 randomized to placebo were similar at baseline. At 24 weeks, metformin compared with placebo did not have significant effects on blood pressure, blood glucose, high-density or low-density lipoprotein cholesterol, but it did reduce total serum cholesterol (0.2 mmol/l, P = 0.038). Metformin also significantly reduced weight (-0.7 kg, P = 0.006), BMI (-0.2 kg/m, P = 0.024), waist circumference (-0.9 cm, P = 0.008), and both subcutaneous (-6.1 cm, P = 0.043) and visceral adiposity (-5.4 cm, P = 0.028) as measured by computed tomography, and lowered serum high-sensitivity C-reactive protein levels (-0.6 mg/dl, P < 0.001). There was no significant difference in adverse events (P = 0.785). CONCLUSIONS: Metformin has no effect on blood pressure and blood glucose levels, but it does reduce total cholesterol, abdominal obesity and C-reactive protein levels in obese hypertensive patients without diabetes.


Assuntos
Hipertensão/tratamento farmacológico , Metformina/uso terapêutico , Obesidade/complicações , Adulto , Idoso , Glicemia/análise , Pressão Sanguínea , China , Colesterol/sangue , Colesterol/classificação , Método Duplo-Cego , Feminino , Humanos , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Obesidade/diagnóstico por imagem , Placebos , Ultrassonografia
10.
PLoS One ; 7(3): e32628, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22438881

RESUMO

Increased transient receptor potential canonical type 3 (TRPC3) channels have been observed in patients with essential hypertension. In the present study we tested the hypothesis that increased monocyte migration is associated with increased TRPC3 expression. Monocyte migration assay was performed in a microchemotaxis chamber using chemoattractants formylated peptide Met-Leu-Phe (fMLP) and tumor necrosis factor-α (TNF-α). Proteins were identified by immunoblotting and quantitative in-cell Western assay. The effects of TRP channel-inhibitor 2-aminoethoxydiphenylborane (2-APB) and small interfering RNA knockdown of TRPC3 were investigated. We observed an increased fMLP-induced migration of monocytes from hypertensive patients compared with normotensive control subjects (246 ± 14% vs 151 ± 10%). The TNF-α-induced migration of monocytes in patients with essential hypertension was also significantly increased compared to normotensive control subjects (221 ± 20% vs 138 ± 18%). In the presence of 2-APB or after siRNA knockdown of TRPC3 the fMLP-induced monocyte migration was significantly blocked. The fMLP-induced changes of cytosolic calcium were significantly increased in monocytes from hypertensive patients compared to normotensive control subjects. The fMLP-induced monocyte migration was significantly reduced in the presence of inhibitors of tyrosine kinase and phosphoinositide 3-kinase. We conclude that increased monocyte migration in patients with essential hypertension is associated with increased TRPC3 channels.


Assuntos
Hipertensão/sangue , Monócitos/fisiologia , Canais de Cátion TRPC/sangue , Idoso , Sequência de Bases , Compostos de Boro/farmacologia , Cálcio/sangue , Estudos de Casos e Controles , Movimento Celular , Citosol/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Humanos , Técnicas In Vitro , Sistema de Sinalização das MAP Quinases , Masculino , Pessoa de Meia-Idade , Monócitos/classificação , Monócitos/efeitos dos fármacos , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Fosfatidilinositol 3-Quinases/sangue , Proteínas Tirosina Quinases/sangue , Proteínas Proto-Oncogênicas c-akt/sangue , RNA Interferente Pequeno/genética , Canais de Cátion TRPC/agonistas , Canais de Cátion TRPC/antagonistas & inibidores , Canais de Cátion TRPC/genética
11.
Pflugers Arch ; 463(5): 727-32, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22395410

RESUMO

Nonalcoholic fatty liver is characterized by the fatty deformation and lipid deposition of hepatic parenchymal cells that are associated with cardiometabolic diseases. In this study, we report the effect of capsaicin on its receptor, transient receptor potential vanilloid 1 (TRPV1) cation channel, in preventing fatty liver formation. Functional TRPV1 has been detected in hepatocytes and liver tissues. TRPV1 activation by capsaicin reduced lipid accumulation and triglyceride level in the liver from wild-type (WT) mice. However, these effects were absent in the liver from TRPV1(-/-) mice. Chronic dietary capsaicin increased the hepatic uncoupling protein 2 (UCP2) expression in WT but not in TRPV1(-/-) mice (P < 0.01). We conclude that TRPV1 long-time activation might prevent high-fat diet-induced fatty liver in mice through upregulation of hepatic UCP2. Dietary capsaicin may represent a promising intervention in populations at high risk for fatty liver.


Assuntos
Fígado Gorduroso/prevenção & controle , Canais Iônicos/genética , Canais Iônicos/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Capsaicina/metabolismo , Células Cultivadas , Dieta Hiperlipídica/efeitos adversos , Gorduras Insaturadas na Dieta/metabolismo , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica , Triglicerídeos/metabolismo , Proteína Desacopladora 2 , Regulação para Cima
12.
J Cardiovasc Pharmacol ; 59(6): 500-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22343369

RESUMO

Recent studies have shown that atorvastain has anti-inflammatory effect and can prevent cardiac hypertrophy. The development of cardiac hypertrophy and dysfunction is associated with an increase in cardiac glucose utilization. In this study, we investigated the effect of atorvastatin on glucose oxidation in tumor necrosis factor α (TNF-α)-stimulated cardiomyocytes (H9c2 cells) and the potential role of peroxisome proliferation-activated receptor coactivator 1α (PGC-1α) in this effect. Exposure of H9c2 cells to TNF-α inhibited the expressions of PGC-1α, pyruvate dehydrogenase kinase 4, and carnitine palmityl transferase 1 and induced a significant increase in glucose oxidation rate. However, the effects of TNF-α were significantly reversed by atorvastatin. Selective silence of PGC-1α in H9c2 cells resulted in the downregulation of pyruvate dehydrogenase kinase 4 and carnitine palmityl transferase 1 and further increased the TNF-α-induced glucose oxidation. Interestingly, the effect of atorvastatin on PGC-1α was almost abolished by mevalonate and partially by farnesol but not by geranylgeraniol. In conclusion, atorvastatin inhibits TNF-α-induced glucose oxidation through PGC-1α upregulation in cardiomyocytes, which might be associated with the regulation of isoprenoid metabolites.


Assuntos
Glucose/metabolismo , Ácidos Heptanoicos/farmacologia , Pirróis/farmacologia , Proteínas de Ligação a RNA/genética , Fatores de Transcrição/genética , Regulação para Cima/efeitos dos fármacos , Animais , Atorvastatina , Carnitina O-Palmitoiltransferase/genética , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Oxirredução/efeitos dos fármacos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Proteínas Quinases/genética , Ratos , Fator de Necrose Tumoral alfa/administração & dosagem
13.
J Mol Cell Biol ; 4(2): 88-96, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22241835

RESUMO

Brown adipose tissue (BAT) is an energy-expending organ that produces heat. Expansion or activation of BAT prevents obesity and diabetes. Chronic cold exposure enhances thermogenesis in BAT through uncoupling protein 1 (UCP1) activation triggered via a ß-adrenergic pathway. Here, we report that the cold-sensing transient receptor potential melastatin 8 (TRPM8) is functionally present in mouse BAT. Challenging brown adipocytes with menthol, a TRPM8 agonist, up-regulates UCP1 expression and requires protein kinase A activation. Upon mimicking long-term cold exposure with chronic dietary menthol application, menthol significantly increased the core temperatures and locomotor activity in wild-type mice; these effects were absent in both TRPM8(-/-) and UCP1(-/-) mice. Dietary obesity and glucose abnormalities were also prevented by menthol treatment. Our results reveal a previously unrecognized role for TRPM8, suggesting that stimulation of this channel mediates BAT thermogenesis, which could constitute a promising way to treat obesity.


Assuntos
Canais Iônicos/metabolismo , Proteínas Mitocondriais/metabolismo , Obesidade/metabolismo , Obesidade/prevenção & controle , Canais de Cátion TRPM/metabolismo , Termogênese , Sensação Térmica , Animais , Temperatura Baixa , Feminino , Humanos , Canais Iônicos/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Mitocondriais/genética , Obesidade/genética , Obesidade/fisiopatologia , Canais de Cátion TRPM/genética , Proteína Desacopladora 1
14.
J Diabetes ; 4(1): 22-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22040104

RESUMO

The prevalence of type 2 diabetes mellitus (T2DM) has increased markedly worldwide. A recent epidemiological study reported that approximately 63% of T2DM patients also have high blood pressure (>130/80 mmHg), which doubles their risk of cardiac events. Of the medications used to treat T2DM, the incretins are a group of peptides that not only regulate blood glucose effectively and moderately, but also protect patients against cardiovascular events and improve several cardiovascular parameters. Here were review data from preclinical and short- and long-term clinical studies investigating the antihypertensive effects of incretins. We also elucidate four possible mechanisms underlying the antihypertensive effects of incretins. We conclude that incretins can lower blood pressure of T2DM patients, independent of weight loss, and will surely improve the prognosis of these patients.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/tratamento farmacológico , Hipertensão/tratamento farmacológico , Incretinas/uso terapêutico , Animais , Pressão Sanguínea/efeitos dos fármacos , Humanos , Incretinas/farmacologia
15.
PPAR Res ; 2011: 291656, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22190906

RESUMO

Vascular endothelial dysfunction has been demonstrated in metabolic syndrome (MS). Chronic administration of rosiglitazone ameliorates endothelial dysfunction through PPARγ-mediated metabolic improvements. Recently, studies suggested that single dose of rosiglitazone also has direct vascular effects, but the mechanisms remain uncertain. Here we established a diet-induced rat model of MS. The impaired vasorelaxation in MS rats was improved by incubating arteries with rosiglitazone for one hour. Importantly, this effect was blocked by either inhibition of PPARγ or PPARδ. In cultured endothelial cells, acute treatment with rosiglitazone increased the phosphorylation of Akt and eNOS and the production of NO. These effects were also abolished by inhibition of PPARγ, PPARδ, or PI3K. In conclusion, rosiglitazone improved endothelial function through both PPARγ- and PPARδ-mediated phosphorylation of Akt and eNOS, which might help to reconsider the complex effects and clinical applications of rosiglitazone.

16.
Stroke ; 42(11): 3245-51, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21852608

RESUMO

BACKGROUND AND PURPOSE: Previous studies show that endothelial nitric oxide synthase (eNOS) plays a prominent role in maintaining cerebral blood flow and preventing stroke. Capsaicin in hot pepper can increase the phosphorylation of eNOS in endothelial cells. We test the hypothesis that chronic dietary capsaicin can prevent stroke through activation of cerebrovascular transient receptor potential vanilloid 1 (TRPV1) channels in stroke-prone spontaneously hypertensive rats (SHRsp). METHODS: SHRsp were fed dietary capsaicin, and their onset of stroke was examined. TRPV1 knockout and transgenic mice were used for determining the function of TRPV1 channels. Expression of eNOS and cerebrovascular reactivity were examined. RESULTS: Immunofluorescence showed TRPV1 channels and eNOS coexpression in cerebral arterioles. Administration of capsaicin significantly increased phosphorylated eNOS in carotid arteries from wild-type mice but not in TRPV1 knockout mice. Inhibition of eNOS using N(G)-nitro-L-arginine methyl ester, removal of endothelium, or mutant TRPV1 significantly reduced capsaicin-induced endothelium-dependent relaxation of basilar arteries in mice. Chronic dietary capsaicin also remarkably increased eNOS expression in carotid arteries from SHRsp. Compared with Wistar-Kyoto rats, SHRsp had impaired endothelium-dependent relaxation of basilar arteries. Administration of capsaicin or L-arginine significantly improved the endothelium-dependent relaxation of basilar arteries in SHRsp. SHRsp had hypertrophy of cerebral arterioles, which was reversed by dietary capsaicin. Importantly, long-term administration of capsaicin significantly delayed the onset of stroke and increased the survival time in SHRsp. CONCLUSIONS: Activation of TRPV1 channels by dietary capsaicin mediated increases in phosphorylation of eNOS and could represent a novel target for dietary intervention of stroke.


Assuntos
Capsaicina/administração & dosagem , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/prevenção & controle , Canais de Cátion TRPV/biossíntese , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Óxido Nítrico Sintase Tipo III/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Acidente Vascular Cerebral/enzimologia , Canais de Cátion TRPV/deficiência , Fatores de Tempo , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia
17.
Transl Res ; 155(2): 71-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20129487

RESUMO

This study investigates the sex difference of cardiometabolic risk profiles in subjects with visceral fat obesity (VFO) but normal waist circumference (WC). VFO, which is defined as visceral adipose tissue (VAT) area more than 100 cm(2) by computed tomography (CT), and cardiometabolic risk profiles were assessed in 437 subjects with normal WC (197 female subjects and 240 male subjects). The expression of adiponectin and its receptor in abdominal adipose tissue was measured in a subgroup of the subjects. Compared with the male subjects, female subjects had a larger abdominal subcutaneous adipose tissue (SAT) area (158+/-56 vs 116+/-38 cm(2), P<0.01), smaller VAT area (67+/-44 vs 78+/-33 cm(2); P<0.01), and lower prevalence of VFO (12.2 vs 24.2%, P<0.001). This finding was accompanied by upregulated expressions of adiponectin and its receptor in abdominal adipose tissue in female subjects. Without VFO, the risk profiles were not significantly different between male subjects and female subjects. Although risk factors were increased and intensified in both sexes in the presence of VFO, female subjects with VFO were associated with greater cardiometabolic risks than male subjects. A regression analysis indicates the ratio of VAT/SAT for female subjects, whereas VAT and age for male subjects were independently associated with clustering of multiple cardiometabolic risk factors. In conclusion, in subjects with normal WC, the prevalence of VFO is lower and the expression of adiponectin and its receptor is higher in female subjects compared with male subjects. Although VFO was associated with increased risk in both sexes, the risk profile in female subjects with VFO was more pronounced.


Assuntos
Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/genética , Obesidade/epidemiologia , Obesidade/genética , Receptores de Adiponectina/genética , Caracteres Sexuais , Adiponectina/genética , Adulto , Idoso , Feminino , Predisposição Genética para Doença/epidemiologia , Humanos , Gordura Intra-Abdominal/patologia , Masculino , Pessoa de Meia-Idade , Obesidade/patologia , Prevalência , Fatores de Risco , Distribuição por Sexo , Circunferência da Cintura , Adulto Jovem
18.
Zhonghua Yi Xue Za Zhi ; 88(34): 2391-4, 2008 Sep 09.
Artigo em Chinês | MEDLINE | ID: mdl-19087712

RESUMO

OBJECTIVE: To compare the values of measurements of obesity, including body mass index(BMI), waist circumference (WC), waist-to-hip ratio (WHR), bioelectrical impedance analyzer(BIA) (fat mass and FAT%), ultrasonography (US) (subcutaneous fat distance and intraabdominal fat distance), and computed tomography (CT) in predicting the quantification of visceral adipose in abdominal obesity, and to evaluate the best cut-off point, sensitivity and specificity of these methods. METHODS: 4,301 inpatients with hypertension, 2,155 males and 2,146 females, aged (56.4 +/- 13.8) (11 - 89), all with at least 1 risk factor of cardiovascular diseases, underwent simple body fat measurement. 3458 received BIA, 2,553 received B mode ultrasonography, 1039 underwent CT examination, and 659 received all kinds of examination. Abdominal visceral adipose area (VA) measured with CT >or= 100 cm(2) was the diagnostic criteria of visceral fat obesity (VFO). Receiver operating characteristic (ROC) curve was used to analyze the body fat indexes to determine the best cut-off point. RESULTS: (1) It was accurate for WC, fat mass, BMI, intraabdominal fat distance, FAT%, and WHR were all accurate in diagnosis of VFO with the values of area under ROC of 0.730 - 0.867. WC was the most effective measurement. (2) The best cut-off points of these methods in predicting abdominal visceral obesity in males and females were as follows: WC: 89.5 cm and 85.5 cm for WC. 25 kg/m(2) and 26 kg/m(2) for BMI, 0.97 and 0.95 for WHR, 29% and 38% for fat composition, 18.6 kg, and 20.4 kg for fat mass, and 38.5 mm and 34.7 mm for intraabdominal fat distance. CONCLUSIONS: WC, fat mass, BMI, intraabdominal fat distance, simple fat parameters, and WHR all can predict visceral adipose in abdominal obesity, in which WC is the best. For a given WC, the type of obesity can be determined by BIA and US.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Obesidade/diagnóstico por imagem , Obesidade/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Composição Corporal , Índice de Massa Corporal , Criança , Impedância Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Ultrassonografia
19.
Zhonghua Yi Xue Za Zhi ; 88(18): 1251-4, 2008 May 13.
Artigo em Chinês | MEDLINE | ID: mdl-18844097

RESUMO

OBJECTIVE: To explore the relationship of different types of abdominal obesity to risk of metabolic syndrome (MS). METHODS: Visceral fat area (VA) and substantial fat area (SA) were assessed by CT in 846 patients, 470 males and 376 females, aged 55 +/- 12, who suffered from at least one cardiometabolic risk factor and divided into 4 groups according to their VA and waist circumference (WC): non-obesity, masked visceral fat obesity (VFO), pseudo-VFO, and VFO groups. Blood pressure, fasting blood glucose, fasting serum insulin, and lipid profile were also measured. The MS risks of different types of abdominal obesity were compared. RESULTS: The prevalence rate of masked VFO of males was 10.9% (51/470), significantly higher than that of female (4.8%, 18/376). The prevalence rate of MS of the male patients with masked VFO was 43.1%, significantly higher than that of those in non-obesity group (25.0%), and lower than those of the males in the pseudo-VFO group (78.7%) and in the VFO group (88.6%), whereas the MS prevalence rate of the males in the pseudo-VFO group was significantly higher than those in the non-obesity and masked VFO groups. On the other hand, the MS prevalence rate of the female patients with masked VFO was 33.3%, not significantly different from that of the female patients in the non-obesity group (31.2%), but significantly lower than those of the pseudo-VFO and VFO groups (78.7% and 90.9% respectively). The MS prevalence rate of the female pseudo-VFO patients was also significantly higher than those in the non-obesity and masked VFO groups. Logistic regression analysis showed that WC and VA were independent risk factors for MS [OR (95% CI) = 1.13 (1.10-1.17), 1.01 (1.01-1.02), respectively, P < 0.01). CONCLUSION: Different types of abdominal obesity have important impacts on the risk of metabolic syndrome. Masked VFO, even though with normal WC, and pseudo-VFO have considerably higher cardiometabolic risks.


Assuntos
Gordura Intra-Abdominal/metabolismo , Doenças Metabólicas/complicações , Obesidade/complicações , Gordura Abdominal/metabolismo , Adulto , Idoso , Glicemia/metabolismo , Distribuição da Gordura Corporal , Índice de Massa Corporal , Feminino , Humanos , Resistência à Insulina , Masculino , Doenças Metabólicas/sangue , Doenças Metabólicas/metabolismo , Pessoa de Meia-Idade , Obesidade/classificação , Obesidade/metabolismo , Fatores de Risco , Síndrome , Relação Cintura-Quadril
20.
Metabolism ; 56(12): 1612-9, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17998010

RESUMO

Observational studies established high-sensitivity C-reactive protein as a risk factor for cardiovascular events in the general population. The goal of this study was to determine the relationship between target organ damage and high-sensitivity C-reactive protein in a cohort of Chinese patients with metabolic syndrome. A total of 1082 consecutive patients of Chinese origin were screened for the presence of metabolic syndrome according to the National Cholesterol Education Program's Adult Treatment Panel III. High-sensitivity C-reactive protein and target organ damage, including cardiac hypertrophy, carotid intima-media thickness, and renal impairment, were investigated. The median (25th and 75th percentiles) of high-sensitivity C-reactive protein in 619 patients with metabolic syndrome was 2.42 mg/L (0.75 and 3.66 mg/L) compared with 1.13 mg/L (0.51 and 2.46 mg/L) among 463 control subjects (P < .01). There was a progressive increase in high-sensitivity C-reactive protein level with the number of components of the metabolic syndrome. Stratification of patients with metabolic syndrome into 3 groups according to their high-sensitivity C-reactive protein concentrations (<1.0, 1.0-3.0, and >3.0 mg/L) showed that the subjects with the elevated high-sensitivity C-reactive protein had a higher percentage of target organ damage than those with lower high-sensitivity C-reactive protein. Stepwise multiple logistic regression confirmed that high-sensitivity C-reactive protein was significantly associated with cardiac hypertrophy, carotid intima-media thickness, and renal impairment. The study shows a strong independent association between inflammation and target organ damage in a large cohort of patients of Chinese origin with metabolic syndrome.


Assuntos
Proteína C-Reativa/metabolismo , Cardiomegalia/metabolismo , Síndrome Metabólica/metabolismo , Albuminúria/metabolismo , Albuminúria/patologia , Povo Asiático , Cardiomegalia/patologia , Estudos de Coortes , Estudos Transversais , Ecocardiografia Doppler , Feminino , Humanos , Modelos Logísticos , Masculino , Síndrome Metabólica/patologia , Pessoa de Meia-Idade , Túnica Íntima/metabolismo , Túnica Íntima/patologia
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