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1.
Int J Mol Sci ; 23(5)2022 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-35269778

RESUMO

As in women with polycystic ovary syndrome (PCOS), hyperinsulinemia is associated with anovulation in PCOS-like female rhesus monkeys. Insulin sensitizers ameliorate hyperinsulinemia and stimulate ovulatory menstrual cycles in PCOS-like monkeys. To determine whether hyperinsulinemia (>694 pmol/L), alone, induces PCOS-like traits, five PCOS-like female rhesus monkeys with minimal PCOS-like traits, and four control females of similar mid-to-late reproductive years and body mass index, received daily subcutaneous injections of recombinant human insulin or diluent for 6−7 months. A cross-over experimental design enabled use of the same monkeys in each treatment phase. Insulin treatment unexpectedly normalized follicular phase duration in PCOS-like, but not control, females. In response to an intramuscular injection of 200 IU hCG, neither prenatally androgenized nor control females demonstrated ovarian hyperandrogenic responses while receiving insulin. An intravenous GnRH (100 ng/kg) injection also did not reveal evidence of hypergonadotropism. Taken together, these results suggest that experimentally induced adult hyperinsulinemia, alone, is insufficient to induce PCOS-like traits in female rhesus monkeys and to amplify intrinsic PCOS-like pathophysiology.


Assuntos
Hiperandrogenismo , Hiperinsulinismo , Síndrome do Ovário Policístico , Animais , Feminino , Humanos , Hiperinsulinismo/induzido quimicamente , Insulina , Macaca mulatta , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/tratamento farmacológico
2.
J Biochem Mol Toxicol ; 36(1): e22931, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34665895

RESUMO

Aluminum phosphide (AlP) is commonly used as a powerful suicidal tool. The exact mechanism of acute toxicity has not been well defined despite high mortality rates as well as its supportive treatment including rapid decontamination and institution of resuscitative measures. The current study aimed to investigate a new combination therapy using trimetazidine, N-acetyl cysteine, vitamin C, and hyperinsulinemia-euglycemia to manage acute AlP poisoning. Acute AlP-induced cardiotoxicity, hemodynamic changes, and hepatotoxicity were evaluated using electrocardiogram, creatinine kinase MB iso-enzyme, troponin-1, blood pressure, random blood glucose level, liver function tests, and histopathological changes in both the heart and liver in a rabbit model of AlP poisoning. The results showed that the new regimen therapy ameliorates the toxic effect of AlP with significant improvement in survival, cardiovascular and hemodynamic parameters in addition to histopathological changes. These results highlight the strong cardioprotective, antioxidant, hepatoprotective effects of the new combined therapy along with correction of hemodynamic changes and hyperglycemia as a potential target in the management of acute AlP poisoning.


Assuntos
Acetilcisteína/farmacologia , Compostos de Alumínio/intoxicação , Ácido Ascórbico/farmacologia , Hiperinsulinismo , Fosfinas/intoxicação , Trimetazidina/farmacologia , Animais , Hiperinsulinismo/induzido quimicamente , Hiperinsulinismo/tratamento farmacológico , Hiperinsulinismo/metabolismo , Masculino , Coelhos
3.
Lancet Diabetes Endocrinol ; 9(11): 776-785, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34600607

RESUMO

Although type 1 diabetes is traditionally considered a disease of lean people, overweight and obesity are becoming increasingly more common in individuals with type 1 diabetes. Non-physiological insulin replacement that causes peripheral hyperinsulinaemia, insulin profiles that do not match basal and mealtime insulin needs, defensive snacking to avoid hypoglycaemia, or a combination of these, are believed to affect body composition and drive excessive accumulation of body fat in people with type 1 diabetes. The consequences of overweight or obesity in people with type 1 diabetes are of particular concern, as they increase the risk of both diabetes-related and obesity-related complications, including cardiovascular disease, stroke, and various types of cancer. In this Review, we summarise the current understanding of the aetiology and consequences of excessive bodyweight in people with type 1 diabetes and highlight the need to optimise future prevention and treatment strategies in this population.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Obesidade/complicações , Adolescente , Cirurgia Bariátrica , Terapia Comportamental , Composição Corporal/efeitos dos fármacos , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/terapia , Feminino , Humanos , Hiperinsulinismo/induzido quimicamente , Hiperinsulinismo/complicações , Lactente , Insulina/efeitos adversos , Insulina/uso terapêutico , Estilo de Vida , Masculino , Obesidade/epidemiologia , Obesidade/terapia , Sobrepeso/complicações , Sobrepeso/epidemiologia , Sobrepeso/terapia , Aumento de Peso/efeitos dos fármacos , Adulto Jovem
4.
Can J Physiol Pharmacol ; 99(12): 1316-1323, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34310895

RESUMO

Free fatty acid (FFA) deposition in non-adipose tissues such as the heart is a characteristic of insulin resistant states which feature hyperinsulinemia and dipeptidyl peptidase-4 (DPP-4) activation. Estrogen-progestin oral contraceptives (OC) treatment reportedly increased DPP-4 activity in rat tissue, and DPP-4 inhibitors have anti-diabetic and anti-inflammatory properties. This study aims to investigate the effects of DPP-4 inhibition on cardiac FFA deposition in estrogen-progestin-treated female rats. From our data, estrogen-progestin OC exposure in female rats led to elevated plasma insulin, cardiac DPP-4 activity, FFA and triglyceride (TG) accumulation, TG/high-density lipoprotein cholesterol (TG/HDL-C) ratio, adenosine deaminase/xanthine oxidase/uric acid pathway (ADA/XO/UA), lipid peroxidation, glycogen synthase activity, and alanine phosphatase; whereas cardiac glucose-6-phosphate dehydrogenase, Na+/K+-ATPase and nitric oxide (NO) were decreased. However, DPP-4 inhibition resulted in decreased plasma insulin, cardiac DPP-4 activity, FFA, TG, TG/HDL-C ratio, and alkaline phosphatase. These were accompanied by reduced ADA/XO/UA pathway, lipid peroxidation, and augmented NO and Na+/K+-ATPase in estrogen-progestin OC-treated rats. DPP-4 inhibition attenuated cardiac lipid deposition accompanied by reduced activity in the ADA/XO/UA pathway in estrogen-progestin OC-treated female rats. DPP-4 is therefore a plausible therapeutic target in cardiometabolic disorders.


Assuntos
Anticoncepcionais Orais Hormonais/efeitos adversos , Inibidores da Dipeptidil Peptidase IV/farmacologia , Estrogênios/efeitos adversos , Ácidos Graxos não Esterificados/metabolismo , Hiperinsulinismo/induzido quimicamente , Hiperinsulinismo/metabolismo , Miocárdio/metabolismo , Progestinas/efeitos adversos , Adenosina Desaminase/metabolismo , Animais , Dipeptidil Peptidase 4/metabolismo , Dipeptidil Peptidase 4/fisiologia , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Feminino , Resistência à Insulina , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/metabolismo , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Ácido Úrico/metabolismo , Xantina Oxidase/metabolismo
5.
Front Endocrinol (Lausanne) ; 12: 694336, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34177815

RESUMO

Smoking during pregnancy is one of the causes of low birthweight. Ingestion of nicotine during pregnancy has various metabolic impacts on the fetus and offspring. According to the developmental origins of health and disease theory, low birthweight is a risk factor for developing various non-communicable diseases, including diabetes. We hypothesized that when nicotine-induced low-birthweight rats, when exposed to a high-fat diet (HFD) after growth, are predisposed to glucose intolerance as a result of a mismatch between the eutrophic environment and small body size. Therefore, we investigated whether hyperinsulinemia was caused by exposure of nicotine-induced low-birthweight rats to HFD, including whether this phenomenon exhibited possible sex differences. The average birthweight and body weight at weaning day of offspring from nicotine-administered dams was lower than those of controls. The offspring from nicotine-administered dams did not show rapid fat accumulation after exposure to HFD, and weight and body fat ratio of these animals did not differ from those of the controls. Blood glucose levels did not differ between the groups, but insulin levels increased only in male HFD-exposed offspring from nicotine-administered dams. Similarly, only in HFD-exposed male from nicotine-administered dams showed decreases in the insulin receptor expression in the liver. We conclude that male rats subjected to prenatal nicotine exposure develop hyperinsulinemia when exposed to HFD after growth. Our results suggest that decreased expression of insulin receptors in the liver may be involved in the mechanism underlying hyperinsulinemia in low-birthweight offspring, a phenomenon that appeared to exhibit a sex-specific bias.


Assuntos
Peso ao Nascer/efeitos dos fármacos , Hiperinsulinismo/induzido quimicamente , Nicotina/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Animais , Feminino , Hiperinsulinismo/metabolismo , Hiperinsulinismo/patologia , Insulina/sangue , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Ratos , Ratos Wistar , Fatores Sexuais
7.
Mitochondrion ; 59: 190-213, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34091077

RESUMO

The aim of this study was to establish the potential effect of Laurus nobilis ethanolic extract on improving insulin sensitivity and protecting liver cells from apoptosis, mitochondrial dysfunction, oxidative stress (OS), and inflammation; all of which considered as major alterations occurring during insulin resistance (IR) as well as diabetes onset, in hyperinsulinemic and hyperglycemic-induced HepG2 cell line. Thereby, L. nobilis ethanolic extract has been first chemically characterized using LC-MS/MS technique. Subsequently, HepG2 cells were pre-treated with an optimal concentration of L. nobilis ethanolic extract for 24 h, and then, subjected to 30 mM D-glucose and 500 nM insulin mixture for another 24 h in order to induce hyperinsulinemia and hyperglycaemia (HI/HG) status. Several parameters such as biocompatibility, hepatotoxicity, reactive oxygen species (ROS), mitochondrial transmembrane potential, dynamics, and metabolism, multicaspase activity, glucose uptake, in addition to genes and proteins expression levels were investigated. The obtained results showed that the bioactive extract of Laurus nobilis increased the number of living cells and their proliferation rate, significantly attenuated apoptosis by modulating pro-apoptotic pathways (p21, p53 and Bax genes), allowed a relative normalization of caspases-activity, and decreased the expression of inflammatory markers including c-Jun, NF-κB and Tlr4 transcripts. L. Nobilis ethanolic extract reduced considerably total intracellular ROS levels in challenged HepG2 cells, and regulated the mitochondrial OXPHOS pathway, demonstrating the potential antioxidant effect of the plant. Ethanolic plant extract increased insulin sensitivity, since an elevated expression of master transcripts responsible for insulin sensitivity including IRS1, IRS2, INSR was found. Taken together, obtained data suggest that L. nobilis ethanolic extract offers new insights in the development of potential antioxidant, insulin sensitizing as well as hepatoprotective drugs.


Assuntos
Antioxidantes/farmacologia , Etanol/farmacologia , Hiperglicemia/metabolismo , Extratos Vegetais/química , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Cromatografia Líquida , Glucose/efeitos adversos , Células Hep G2 , Humanos , Hiperglicemia/induzido quimicamente , Hiperglicemia/tratamento farmacológico , Hiperinsulinismo/induzido quimicamente , Insulina/efeitos adversos , Resistência à Insulina , Modelos Biológicos , Biogênese de Organelas , Fosforilação Oxidativa/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espectrometria de Massas em Tandem
8.
PLoS One ; 16(3): e0247638, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33764994

RESUMO

CONTEXT: Obesity, is a state of chronic inflammation, characterized by elevated lipids, insulin resistance and relative hypogonadotropic hypogonadism. We have defined the accompanying decreased Luteinizing Hormone (LH), Follicle-Stimulating Hormone (FSH), ovarian steroids and reduced pituitary response to Gonadotropin-releasing Hormone (GnRH) as Reprometabolic syndrome, a phenotype that can be induced in healthy normal weight women (NWW) by acute infusion of free fatty acids and insulin. OBJECTIVE: To identify potential mediators of insulin and lipid-related reproductive endocrine dysfunction. DESIGN, SETTING, PARTICIPANTS: Secondary analysis of crossover study of eumenorrheic reproductive aged women of normal Body Mass Index (BMI) (<25 kg/m2) at an academic medical center. INTERVENTION: Participants underwent 6-hour infusions of either saline/heparin or insulin plus fatty acids (Intralipid plus heparin), in the early follicular phase of sequential menstrual cycles, in random order. Euglycemia was maintained by glucose infusion. Frequent blood samples were obtained. MAIN OUTCOME MEASURES: Pooled serum from each woman was analyzed for cytokines, interleukins, chemokines, adipokines, Fibroblast Growth Factor-21 (FGF-21) and markers of endoplasmic reticulum (ER) stress (CHOP and GRP78). Wilcoxon signed-rank tests were used to compare results across experimental conditions. RESULTS: Except for Macrophage Inflammatory Protein-1ß (MIP-1ß), no significant differences were observed in serum levels of any of the inflammatory signaling or ER stress markers tested. CONCLUSION: Acute infusion of lipid and insulin, to mimic the metabolic syndrome of obesity, was not associated with an increase in inflammatory markers. These results imply that the endocrine disruption and adverse reproductive outcomes of obesity are not a consequence of the ambient inflammatory environment but may be mediated by direct lipotoxic effects on the hypothalamic-pituitary-ovarian (HPO) axis.


Assuntos
Ácidos Graxos não Esterificados/administração & dosagem , Hiperinsulinismo/metabolismo , Hiperlipidemias/metabolismo , Insulina/administração & dosagem , Síndrome Metabólica/metabolismo , Transdução de Sinais , Centros Médicos Acadêmicos , Adolescente , Adulto , Índice de Massa Corporal , Estudos Cross-Over , Citocinas/genética , Citocinas/metabolismo , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Emulsões Gordurosas Intravenosas/administração & dosagem , Feminino , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Hormônio Foliculoestimulante/genética , Hormônio Foliculoestimulante/metabolismo , Expressão Gênica , Aptidão Genética/efeitos dos fármacos , Aptidão Genética/genética , Técnica Clamp de Glucose , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Hiperinsulinismo/induzido quimicamente , Hiperinsulinismo/genética , Hiperinsulinismo/patologia , Hiperlipidemias/induzido quimicamente , Hiperlipidemias/genética , Hiperlipidemias/patologia , Hormônio Luteinizante/genética , Hormônio Luteinizante/metabolismo , Síndrome Metabólica/induzido quimicamente , Síndrome Metabólica/genética , Síndrome Metabólica/patologia , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo
9.
Cardiovasc Drugs Ther ; 35(6): 1291-1304, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33687595

RESUMO

PURPOSE: Perivascular adipose tissue (PVAT) exerts an anti-contractile effect which is vital in regulating vascular tone. This effect is mediated via sympathetic nervous stimulation of PVAT by a mechanism which involves noradrenaline uptake through organic cation transporter 3 (OCT3) and ß3-adrenoceptor-mediated adiponectin release. In obesity, autonomic dysfunction occurs, which may result in a loss of PVAT function and subsequent vascular disease. Accordingly, we have investigated abnormalities in obese PVAT, and the potential for exercise in restoring function. METHODS: Vascular contractility to electrical field stimulation (EFS) was assessed ex vivo in the presence of pharmacological tools in ±PVAT vessels from obese and exercised obese mice. Immunohistochemistry was used to detect changes in expression of ß3-adrenoceptors, OCT3 and tumour necrosis factor-α (TNFα) in PVAT. RESULTS: High fat feeding induced hypertension, hyperglycaemia, and hyperinsulinaemia, which was reversed using exercise, independent of weight loss. Obesity induced a loss of the PVAT anti-contractile effect, which could not be restored via ß3-adrenoceptor activation. Moreover, adiponectin no longer exerts vasodilation. Additionally, exercise reversed PVAT dysfunction in obesity by reducing inflammation of PVAT and increasing ß3-adrenoceptor and OCT3 expression, which were downregulated in obesity. Furthermore, the vasodilator effects of adiponectin were restored. CONCLUSION: Loss of neutrally mediated PVAT anti-contractile function in obesity will contribute to the development of hypertension and type II diabetes. Exercise training will restore function and treat the vascular complications of obesity.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Obesidade/fisiopatologia , Obesidade/terapia , Condicionamento Físico Animal/fisiologia , Animais , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Hiperglicemia/induzido quimicamente , Hiperinsulinismo/induzido quimicamente , Hipertensão/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 3 de Transcrição de Octâmero/efeitos dos fármacos , Receptores Adrenérgicos beta 3/efeitos dos fármacos , Fator de Necrose Tumoral alfa/efeitos dos fármacos
10.
Acta Pharmacol Sin ; 42(5): 735-743, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32770172

RESUMO

Insulin resistance (IR) is a major metabolic risk factor even before the onset of hyperglycemia. Recently, berberine (BBR) is found to improve hyperglycemia and IR. In this study, we investigated whether BBR could improve IR independent of hyperglycemia. Acute insulin-resistant state was induced in rats by systemic infusion of intralipid (6.6%). BBR was administered via different delivery routes before or after the beginning of a 2-h euglycemic-hyperinsulinemic clamp. At the end of experiment, rats were sacrificed, gastrocnemius muscle was collected for detecting mitochondrial swelling, phosphorylation of Akt and AMPK, as well as the mitochondrial permeability regulator cyclophilin D (CypD) protein expression. We showed that BBR administration markedly ameliorated intralipid-induced IR without affecting blood glucose, which was accompanied by alleviated mitochondrial swelling in skeletal muscle. We used human skeletal muscle cells (HSMCs), AML12 hepatocytes, human umbilical vein endothelial cells, and CypD knockout mice to investigate metabolic and molecular alternations. In either HSMCs or AML12 hepatocytes, BBR (5 µM) abolished palmitate acid (PA)-induced increase of CypD protein levels. In CypD-deficient mice, intralipid-induced IR was greatly attenuated and the beneficial effect of BBR was diminished. Furthermore, we demonstrated that the inhibitory effect of BBR on intralipid-induced IR was mainly mediated by skeletal muscle, but not by intestine, liver, or microvasculature; BBR administration suppressed intralipid-induced upregulation of CypD expression in skeletal muscle. These results suggest that BBR alleviates intralipid-induced IR, which is related to the inhibition of CypD protein expression in skeletal muscle.


Assuntos
Berberina/uso terapêutico , Hiperinsulinismo/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Resistência à Insulina/fisiologia , Animais , Linhagem Celular , Ciclofilinas/metabolismo , Emulsões , Humanos , Hiperinsulinismo/induzido quimicamente , Hiperinsulinismo/metabolismo , Masculino , Camundongos , Células Musculares/efeitos dos fármacos , Células Musculares/metabolismo , Fosfolipídeos , Ratos Sprague-Dawley , Óleo de Soja
11.
Peptides ; 131: 170370, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32663503

RESUMO

Gut hormones affect cardiac function and contractility. In this study, we examined whether insulin affects the cardiac atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) gene expression and release of proANP-derived peptides in pigs. Anaesthetized pigs were included in an experimental study comparing the effect of hyperinsulinemia in 15 pigs submitted to two different protocols versus 11 control pigs receiving saline infusion. Phosphorylation of Akt on Thr308 was determined by western blotting with a pAkt-Thr308 antibody. The mRNA contents of ANP and BNP were determined with real-time PCR; plasma and cardiac tissue proANP was measured with an immunoluminometric assay targeted against the mid-region of the propeptide and a processing-independent assay. Insulin stimulation increased phosphorylation of Akt Thr308 in both left atrium and left ventricle of porcine hearts (p < 0.005). No change was observed in ANP and BNP mRNA contents in the right or left atrium. BNP mRNA contents in the left ventricle, however, decreased 3-fold (p = 0.02) compared to control animals, whereas the BNP mRNA content in the right ventricle as well as ANP mRNA content in the right and left ventricle did not change following hyperinsulinemia. Moreover, the peptide contents did not change in the four cardiac chambers. Finally, proANP concentrations in plasma did not change during the insulin infusion compared to the control animals. These results suggest that insulin does not have direct effect on atrial natriuretic peptide expression but may have a role in the left ventricle.


Assuntos
Fator Natriurético Atrial/genética , Glicemia/metabolismo , Hiperinsulinismo/genética , Hiperinsulinismo/veterinária , Insulina/administração & dosagem , Peptídeo Natriurético Encefálico/genética , Animais , Fator Natriurético Atrial/metabolismo , Feminino , Regulação da Expressão Gênica , Técnica Clamp de Glucose/métodos , Átrios do Coração/efeitos dos fármacos , Átrios do Coração/metabolismo , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Hiperinsulinismo/sangue , Hiperinsulinismo/induzido quimicamente , Infusões Intravenosas , Peptídeo Natriurético Encefálico/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Suínos
12.
Hum Exp Toxicol ; 39(9): 1190-1199, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32207356

RESUMO

Earlier, we demonstrated that chronic exposure to monocrotophos (MCP) elicits insulin resistance in rats along with increased white adipose tissue (WAT) weights. This study was carried out to delineate the biochemical and molecular changes in adipose tissues of rats subjected to chronic exposure to MCP (0.9 and 1.8 mg/kg bw/d for 180 days). Pesticide-treated rats exhibited increased fasting glucose and hyperinsulinemia as well as dyslipidemia. Tumor necrosis factor-alpha and leptin levels were elevated, while adiponectin level was suppressed in plasma of treated rats. MCP treatment caused discernable increase in the weights of perirenal and epididymal WAT. Acetyl coenzyme A carboxylase, fatty acid synthase, glyceraldehyde-3-phosphate dehydrogenase, lipin-1, and lipolytic activities were elevated in the WAT of MCP-treated rats. Corroborative changes were observed in the expression profile of proteins that are involved in lipogenesis and adipose tissue differentiation. Our results clearly demonstrate that long-term exposure to organophosphorus insecticides (OPIs) such as MCP has far-reaching consequences on metabolic health as evidenced by the association of adipogenic outcomes with insulin resistance, hyperinsulinemia, endocrine dysregulations, and dyslipidemia. Taken together, our results suggest that long-term exposure to OPI may be a risk factor for metabolic dysregulations.


Assuntos
Tecido Adiposo Branco/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Inseticidas/toxicidade , Doenças Metabólicas/induzido quimicamente , Monocrotofós/toxicidade , Tecido Adiposo Branco/metabolismo , Animais , Glicemia/análise , Hiperinsulinismo/induzido quimicamente , Hipoglicemia/induzido quimicamente , Resistência à Insulina , Lipídeos/sangue , Lipólise , Masculino , Ratos , Ratos Wistar , Aumento de Peso
14.
J Cell Biochem ; 120(9): 16195-16205, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31081130

RESUMO

Methylmercury (MeHg) is an extremely important environmental toxicant posing serious health risks to human health and a big source of environmental pollutant. Numerous evidence available showing a link between nervous system toxicity and MeHg exposure. Other forms of mercury are reason of metabolic toxic effects and alteration of DNA in the human body. The sources of exposure could be occupational or other environmental settings. In the present study MeHg was orally gavaged to mice, at doses of 2.5, 5, and 10 mg/kg for 4 weeks. Fasting hyperglycemia, activity of hepatic phoshphoenolpyruvate carboxykinase and glucose 6-phoshphate were reported high as compared to control group. Inflammatory markers like, tumor necrosis factor α, the actual end product of inflammatory mediators' cascade pathway was also raised in comparison to control group. Hyperinsulinemia observed in serum showed clear understanding of mercury induced insulin resistance. Moreover, tissue damage due to increased oxidative stress markers like, hepatic lipid peroxidation, 8-deoxygunosine, reactive oxygen species, and carbonyl groups was significantly higher as compared to control group. MeHg caused a significant reduction in antioxidant markers like ferric reducing antioxidant power and total thiol molecules. The present study highlighted that activity of key enzymes involved in glucose metabolism is changed, owing to MeHg induced toxicity in the liver. Induction of similar toxic effects assumed to be stimulated by the production of high quantity free radicals.


Assuntos
Biomarcadores/metabolismo , Hiperinsulinismo/induzido quimicamente , Fígado/metabolismo , Compostos de Metilmercúrio/efeitos adversos , Animais , Hiperinsulinismo/metabolismo , Resistência à Insulina , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Compostos de Metilmercúrio/administração & dosagem , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
15.
J Steroid Biochem Mol Biol ; 190: 54-63, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30923014

RESUMO

Oral contraception is the most commonly used interventional method in the world. However, several women employ the continuous use of these hormones to avoid pre- and menstruation discomforts. Some studies indicate that oral contraceptives are associated with disturbances in glycemia and the effects of the use of a continuous regime are poorly elucidated. Herein, we evaluated the effects of the continuous administration of a combined oral contraceptive (COC) composed by ethinyl estradiol (EE) and drospirenone (DRSP) on glucose homeostasis in female mice. Adult Swiss mice received 0.6 µg EE and 60 µg DRSP (COC group) or vehicle [control (CTL)] daily by gavage for 35 days. COC treatment had no effect on body weight or adiposity, but increased uterus weight and induced hepatomegaly. Importantly, COC females displayed normal glycemia and glucose tolerance, but hyperinsulinemia and lower plasma C-peptide/insulin ratio, indicating reduced insulin clearance. Furthermore, COC mice displayed reduced protein content of the ß subunit of the insulin receptor (IRß) in the liver. Additionally, pancreatic islets isolated from COC mice secreted more insulin in response to increasing glucose concentrations. This effect was associated with the activity of steroid hormones, since INS-1E cells incubated with EE plus DRSP also secreted more insulin. Therefore, we provide the first evidence that the continuous administration of EE and DRSP lead to hyperinsulinemia, due to enhancement of insulin secretion and the reduction of insulin degradation, which possibly lead to the down-regulation of hepatic IRß. These findings suggest that the continuous administration of COC could cause insulin resistance with the prolongation of treatment.


Assuntos
Androstenos/efeitos adversos , Anticoncepcionais Orais Combinados/efeitos adversos , Etinilestradiol/efeitos adversos , Hiperinsulinismo/induzido quimicamente , Células Secretoras de Insulina/efeitos dos fármacos , Insulina/metabolismo , Animais , Feminino , Glucose/metabolismo , Hiperinsulinismo/metabolismo , Resistência à Insulina , Células Secretoras de Insulina/metabolismo , Camundongos
16.
Int J Mol Sci ; 20(3)2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30717287

RESUMO

Atypical antipsychotics, such as olanzapine, are commonly prescribed to patients with schizophrenic symptoms and other psychiatric disorders. However, weight gain and metabolic disturbance cause adverse effects, impair patient compliance and limit clinical utility. Thus, a better understanding of treatment-acquired adverse effects and identification of targets for therapeutic intervention are believed to offer more clinical benefits for patients with schizophrenia. Beyond its nutritional effects, studies have indicated that supplementation of chromium brings about beneficial outcomes against numerous metabolic disorders. In this study, we investigated whether olanzapine-induced weight gain and metabolic disturbance involved chromium dynamic mobilization in a female Sprague-Dawley rat model, and whether a dietary supplement of chromium improved olanzapine-acquired adverse effects. Olanzapine medicated rats experienced weight gain and adiposity, as well as the development of hyperglycemia, hyperinsulinemia, insulin resistance, hyperlipidemia, and inflammation. The olanzapine-induced metabolic disturbance was accompanied by a decrease in hepatic Akt and AMP-activated Protein Kinase (AMPK) actions, as well as an increase in serum interleukin-6 (IL-6), along with tissue chromium depletion. A daily intake of chromium supplements increased tissue chromium levels and thermogenic uncoupling protein-1 (UCP-1) expression in white adipose tissues, as well as improved both post-olanzapine weight gain and metabolic disturbance. Our findings suggest that olanzapine medicated rats showed a disturbance of tissue chromium homeostasis by inducing tissue depletion and urinary excretion. This loss may be an alternative mechanism responsible for olanzapine-induced weight gain and metabolic disturbance.


Assuntos
Adiposidade/efeitos dos fármacos , Antipsicóticos/efeitos adversos , Cloretos/farmacologia , Compostos de Cromo/farmacologia , Hiperglicemia/metabolismo , Hiperinsulinismo/metabolismo , Hiperlipidemias/metabolismo , Olanzapina/efeitos adversos , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Adiposidade/genética , Administração Oral , Animais , Cloretos/metabolismo , Compostos de Cromo/metabolismo , Feminino , Regulação da Expressão Gênica , Hiperglicemia/induzido quimicamente , Hiperglicemia/genética , Hiperglicemia/prevenção & controle , Hiperinsulinismo/induzido quimicamente , Hiperinsulinismo/genética , Hiperinsulinismo/prevenção & controle , Hiperlipidemias/induzido quimicamente , Hiperlipidemias/genética , Hiperlipidemias/prevenção & controle , Inflamação , Resistência à Insulina/genética , Interleucina-6/genética , Interleucina-6/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo , Aumento de Peso/efeitos dos fármacos
17.
Microcirculation ; 26(2): e12501, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30178465

RESUMO

BACKGROUND: Type 2 diabetes and associated vascular complications cause substantial morbidity and mortality. It is important to investigate mechanisms and test therapies in relevant physiological models, yet few animal models adequately recapitulate all aspects of the human condition. OBJECTIVE: We sought to determine the potential of using an insulin receptor antagonist, S961, in mice for investigating vascular pathophysiology. METHODS: S961 was infused into mice for 4 weeks. Blood glucose was monitored, and insulin was measured at the end of the protocol. Blood pressure and pressor responses to vasodilators were measured in cannulated mice, and vascular reactive oxygen and nitrogen species were measured in isolated tissue. RESULTS: S961 infusion-induced hyperglycemia and hyperinsulinemia. There was evidence of increased vascular reactive oxygen and nitrogen species and modification of NO-mediated signaling. Pressor responses to a NO donor were attenuated, but responses to bradykinin were preserved. CONCLUSIONS: Infusion of S961, an insulin receptor antagonist, results in the production of a mouse model of type 2 diabetes that may be useful for investigating redox signaling in the vasculature of insulin-resistant mice over the short term. It is limited by both the transient nature of the hyperglycemia and incomplete functional analogy to the human condition.


Assuntos
Diabetes Mellitus Experimental/induzido quimicamente , Modelos Animais de Doenças , Peptídeos/farmacologia , Receptor de Insulina/antagonistas & inibidores , Animais , Vasos Sanguíneos/metabolismo , Diabetes Mellitus Tipo 2/induzido quimicamente , Hiperglicemia/induzido quimicamente , Hiperinsulinismo/induzido quimicamente , Resistência à Insulina , Camundongos , Oxirredução , Transdução de Sinais
18.
J Pharm Pharmacol ; 71(3): 408-416, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30427077

RESUMO

OBJECTIVES: A large amount of fructose is metabolized in the liver and causes hepatic functional damage. Δ9 -tetrahydrocannabinol (THC) is known as a therapeutic agent for clinical and experimental applications. The study aims to investigate the effects of THC treatment on inflammation, lipid profiles and oxidative stress in rat liver with hyperinsulinemia. METHODS: Sprague-Dawley rats were divided into groups: control, fructose (10% fructose in drinking water for 12 weeks), THC (1.5 mg/kg/day for the last 4 weeks, intraperitoneally) and fructose+THC groups. Biochemical parameters were measured spectrophotometrically. ELISA method was used for insulin measurement. Apoptosis and inflammation markers were detected by the streptavidin-biotin peroxidase method. KEY FINDINGS: The consumptions of food and fluid are inversely proportional to fructose and non-fructose groups. Insulin levels were the highest in fructose group. The reduced glutathione-S-transferase level significantly increased in fructose + THC group compared with fructose group. Total cholesterol level in the fructose + THC group was higher than the fructose group. Caspase-3 and NF-κß immunopositive cell numbers increased in fructose + THC rats compared with fructose group. The number of IL-6 immunopositive cell decreased in fructose + THC group compared with fructose group. CONCLUSIONS: According to the result, long-term and low-dose THC administration may reduce hyperinsulinemia and inflammation in rats to some extent.


Assuntos
Dronabinol/farmacologia , Hiperinsulinismo/tratamento farmacológico , Inflamação/tratamento farmacológico , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Animais , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Frutose/farmacologia , Glutationa/metabolismo , Hiperinsulinismo/induzido quimicamente , Hiperinsulinismo/metabolismo , Inflamação/metabolismo , Insulina/metabolismo , Resistência à Insulina/fisiologia , Fígado/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
19.
Sci Rep ; 8(1): 17037, 2018 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-30451881

RESUMO

Caramel colours are the preferential food colouring agent globally, reaches wide age groups through eatables. Colas, a sweetened carbonated drink are most common caramel coloured beverage and its consumption is linked with diabetes, obesity, pancreatic cancer and other endocrine disorders. A major by-product produced during caramelization is 4-methylimidazole (4-MEI) that is detected in noteworthy concentrations in colas and other beverages. Previous studies revealed the neurotoxic and carcinogenic potential of 4-MEI in animals at higher doses but the effect of 4-MEI at theoretical maximum daily intake dose on glucose homeostasis is unexplored. Here, mice treated with 4-MEI (32 µg/kg bodyweight/day) for seven weeks exhibited severe hypoglycaemia and hyperinsulinemia mediated by hyperplasia of pancreatic beta cells and induces metabolic alterations. On combinatorial treatment, 4-MEI suppressed the glucogenic potential of non-artificial sweeteners and promotes lipogenesis. Furthermore, increased levels of C-peptide, LDL-cholesterol and triglycerides were observed in the humans with regular intake of 4-MEI containing beverages. In summary, 4-MEI induced pancreatic beta cell hyperplasia and leads to disruption of glucose and lipid homeostasis. This study suggests the need for further assessment and reconsideration of the wide usage of 4-MEI containing caramels as food additives.


Assuntos
Glicemia/metabolismo , Homeostase/efeitos dos fármacos , Hiperinsulinismo/induzido quimicamente , Hipoglicemia/induzido quimicamente , Imidazóis/administração & dosagem , Imidazóis/toxicidade , Células Secretoras de Insulina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Feminino , Corantes de Alimentos/administração & dosagem , Corantes de Alimentos/toxicidade , Humanos , Hiperplasia/patologia , Insulina/sangue , Células Secretoras de Insulina/patologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos
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