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1.
Health Sci Rep ; 4(2): e309, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34141903

RESUMO

BACKGROUND: Increasing healthcare costs need to be contained in order to maintain equality of access to care for all EU citizens. A cross-disciplinary consortium of experts was supported by the EU FP7 research programme, to produce a roadmap on cost containment, while maintaining or improving the quality of healthcare. The roadmap comprises two drivers: person-centred care and health promotion; five critical enablers also need to be addressed: information technology, quality measures, infrastructure, incentive systems, and contracting strategies. METHOD: In order to develop and test the roadmap, a COST Action project was initiated: COST-CARES, with 28 participating countries. This paper provides an overview of evidence about the effects of each of the identified enablers. Intersections between the drivers and the enablers are identified as critical for the success of future cost containment, in tandem with maintained or improved quality in healthcare. This will require further exploration through testing. CONCLUSION: Cost containment of future healthcare, with maintained or improved quality, needs to be addressed through a concerted approach of testing key factors. We propose a framework for test lab design based on these drivers and enablers in different European countries.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33668083

RESUMO

BACKGROUND: Person-Centered Care (PCC) is a promising approach towards improved quality of care and cost containment within health systems. It has been evaluated in Sweden and England. This feasibility study examines initial PCC implementation in a rehabilitation hospital for children in Poland. METHODS: The WE-CARE Roadmap of enablers was used to guide implementation of PCC for patients with moderate scoliosis. A multi-disciplinary team of professionals were trained in the PCC approach and the hospital Information Technology (IT) system was modified to enhance PCC data capture. Semi-structured interviews were conducted with the nine health care professionals involved in the pilot study and three patients/parents receiving care. Transcribed data were analyzed via content analysis. RESULTS: 51 patients and their families were treated via a PCC approach. High proportions of new PCC data fields were completed by the professionals. The professionals were able to implement the three core PCC routines and perceived benefits using the PCC approach. Patients and their families also perceived improved quality care. The WE-CARE framework enablers facilitated PCC implementation in this setting. CONCLUSIONS: This feasibility pilot study indicates that the Gothenburg PCC approach can be successfully transferred to a rehabilitation hospital in Poland with favorable perceptions of implementation by both professionals and patients/their families.


Assuntos
Assistência Centrada no Paciente , Criança , Inglaterra , Estudos de Viabilidade , Humanos , Projetos Piloto , Polônia , Suécia
3.
Oncotarget ; 8(53): 91085-91098, 2017 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-29207627

RESUMO

Renal cell carcinoma (RCC), arising from the proximal tubule in the kidney, accounts for approximately 85% of kidney cancers and causes over 140,000 annual deaths worldwide. In the last decade, several new therapies have been identified for treatment of metastatic RCC. Although these therapies increase survival time compared to standard care, none of them has curative properties. The nephrotoxin orellanine specifically targets proximal tubular epithelial cells, leaving other organs unaffected. We therefore hypothesized that the selective toxicity of orellanine extends to clear cell RCC (ccRCC) cells since they emanate from proximal tubular cells. Orellanine would thus target both primary and metastatic ccRCC in vitro and in vivo. We found that orellanine induces dose-dependent cell death in proximal tubular cells and in all ccRCC cells tested, both primary and cell lines, with no toxicity detected in control cells. The toxic action of orellanine involve decreased protein synthesis, disrupted cell metabolism and induction of apoptosis. In nude rats carrying human ccRCC xenografts, brief orellanine treatment eliminated more than 90% of viable tumor mass compared to control rats. This identifies orellanine as a potential treatment concept for ccRCC patients on dialysis, due to its unique selective toxicity towards ccRCC.

5.
Endocrinology ; 154(11): 4226-36, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23913444

RESUMO

Insulin resistance is a key marker of both obesity and GH excess. The purpose of the study was to assess the role of GH on p53-mediated insulin resistance of male mice with obesity due to a high-fat diet. C57BL/6J × CBA male mice fed on a high-fat diet (Obe) were studied; male mice fed a normal diet (Lean) or transgenic mice for bovine GH under the same genetic background (Acro) served as controls. The convergence of p53 and GH pathways was evaluated by Western blot. Obe mice had insulin resistance, which was sustained by a selective increased expression of p53 in adipose tissue. Normal insulin sensitivity was restored, and adipose p53 expression normalized when the GH pathway was blocked. Only the adipose p53 expression was sensitive to the GH blockage, which occurred through the p38 pathway. Adipose tissue of Obe mice had a coordinate overexpression of suppressors of cytokine signal 1-3 and signal transducers and activators of transcription-1, -3, and -5b, not different from that of Acro mice, suggesting an increased sensitivity of adipose tissue to GH. On the contrary, Lean mice were unaffected by changes of GH action. GH seems to be necessary for the increased adipose p53 expression and for insulin resistance of obese mice.


Assuntos
Hormônio do Crescimento/metabolismo , Obesidade/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Acromegalia , Tecido Adiposo/metabolismo , Animais , Hormônio do Crescimento/genética , Resistência à Insulina , Masculino , Camundongos , Camundongos Transgênicos , Proteína Supressora de Tumor p53/genética
6.
J Endocrinol ; 215(2): 257-68, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22917932

RESUMO

GH therapy improves hippocampal functions mainly via circulating IGF1. However, the roles of local GH and IGF1 expression are not well understood. We investigated whether transgenic (TG) overexpression in the adult brain of bovine GH (bGH) under the control of the glial fibrillary acidic protein (GFAP) promoter affected cellular proliferation and the expression of transcripts known to be induced by systemic GH in the hippocampus. Cellular proliferation was examined by 5-bromo-2'-deoxyuridine immunohistochemistry. Quantitative PCR and western blots were performed. Although robustly expressed, bGH-Tg did not increase either cell proliferation or survival. However, bGH-Tg modestly increased Igf1 and Gfap mRNAs, whereas other GH-associated transcripts were unaffected, i.e. the GH receptor (Ghr), IGF1 receptor (Igf1r), 2',3'-cyclic nucleotide 3'-phosphodiesterase (Cnp), ionotropic glutamate receptor 2a (Nr2a (Grin2a)), opioid receptor delta (Dor), synapse-associated protein 90/postsynaptic density-95-associated protein (Sapap2 (Dlgap2)), haemoglobin beta (Hbb) and glutamine synthetase (Gs (Glul)). However, IGF1R was correlated with the expression of Dor, Nr2a, Sapap2, Gs and Gfap. In summary, although local bGH expression was robust, it activated local IGF1 very modestly, which is probably the reason for the low response of previous GH-associated response parameters. This would, in turn, indicate that hippocampal GH is less important than endocrine GH. However, as most transcripts were correlated with the expression of IGF1R, there is still a possibility for endogenous circulating or local GH to act via IGF1R signalling. Possible reasons for the relative bio-inactivity of bGH include the bell-shaped dose-response curve and cell-specific expression of bGH.


Assuntos
Regulação da Expressão Gênica/fisiologia , Hormônio do Crescimento/metabolismo , Hipocampo/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Animais , Peso Corporal , Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Proliferação de Células , Hormônio do Crescimento/genética , Masculino , Camundongos , Camundongos Transgênicos , Neurônios/citologia , Neurônios/metabolismo , Tamanho do Órgão , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
J Endocrinol ; 210(2): 231-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21565853

RESUMO

Apoptosis may occur through the mitochondrial (intrinsic) pathway and activation of death receptors (extrinsic pathway). Young acromegalic mice have reduced cardiac apoptosis whereas elder animals have increased cardiac apoptosis. Multiple intrinsic apoptotic pathways have been shown to be modulated by GH and other stimuli in the heart of acromegalic mice. However, the role of the extrinsic apoptotic pathways in acromegalic hearts is currently unknown. In young (3-month-old) acromegalic mice, expression of proteins of the extrinsic apoptotic pathway did not differ from that of wild-type animals, suggesting that this mechanism did not participate in the lower cardiac apoptosis levels observed at this age. On the contrary, the extrinsic pathway was active in elder (9-month-old) animals (as shown by increased expression of TRAIL, FADD, TRADD and increased activation of death inducing signaling complex) leading to increased levels of active caspase 8. It is worth noting that changes of some pro-apoptotic proteins were induced by GH, which seemed to have, in this context, pro-apoptotic effects. The extrinsic pathway influenced the intrinsic pathway by modulating t-Bid, the cellular levels of which were reduced in young and increased in elder animals. However, in young animals this effect was due to reduced levels of Bid regulated by the extrinsic pathway, whereas in elder animals the increased levels of t-Bid were due to the increased levels of active caspase 8. In conclusion, the extrinsic pathway participates in the cardiac pro-apoptotic phenotype of elder acromegalic animals either directly, enhancing caspase 8 levels or indirectly, increasing t-Bid levels and conveying death signals to the intrinsic pathway.


Assuntos
Acromegalia/metabolismo , Apoptose/fisiologia , Cardiomiopatias/metabolismo , Miocárdio/metabolismo , Transdução de Sinais/fisiologia , Acromegalia/patologia , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Cardiomiopatias/patologia , Bovinos , Camundongos , Camundongos Transgênicos , Miocárdio/patologia
8.
Am J Physiol Endocrinol Metab ; 294(2): E251-60, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18029443

RESUMO

The aim of the present study was to investigate the short- and long-term effects of a high-fat Western diet (WD) on intake, storage, expenditure, and fecal loss of energy as well as effects on locomotor activity and thermogenesis. WD for only 24 h resulted in a marked physiological shift in energy homeostasis, including increased body weight gain, body fat, and energy expenditure (EE) but an acutely lowered locomotor activity. The acute reduction in locomotor activity was observed after only 3-5 h on WD. The energy intake and energy absorption were increased during the first 24 h, lower after 72 h, and normalized between 7 and 14 days on WD compared with mice given chow diet. Core body temperature and EE was increased between 48 and 72 h but normalized after 21 days on WD. These changes paralleled plasma T(3) levels and uncoupling protein-1 expression in brown adipose tissue. After 21 days of WD, energy intake and absorption, EE, and body temperature were normalized. In contrast, the locomotor activity was reduced and body weight gain was increased over the entire 21-day study period on WD. Calculations based on the correlation between locomotor activity and EE in 2-h intervals at days 21-23 indicated that a large portion of the higher body weight gain in the WD group could be attributed to the reduced locomotor activity. In summary, an acute and persisting decrease in locomotor activity is most important for the effect of WD on body weight gain and obesity in mice.


Assuntos
Dieta/efeitos adversos , Atividade Motora/fisiologia , Obesidade/etiologia , Animais , Ácidos Araquidônicos/sangue , Composição Corporal/fisiologia , Temperatura Corporal/fisiologia , Peso Corporal/fisiologia , Calorimetria Indireta , Colesterol na Dieta/efeitos adversos , DNA Complementar/biossíntese , DNA Complementar/genética , Gorduras Insaturadas na Dieta/efeitos adversos , Dopamina/metabolismo , Endocanabinoides , Ingestão de Energia/fisiologia , Metabolismo Energético/fisiologia , Ácidos Graxos/efeitos adversos , Fezes/química , Homeostase/fisiologia , Hormônios/sangue , Hipotálamo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/fisiopatologia , Alcamidas Poli-Insaturadas/sangue , RNA/biossíntese , RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Biochem Biophys Res Commun ; 349(2): 825-32, 2006 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-16945327

RESUMO

Using the mouse as a model organism in pharmaceutical research presents unique advantages as its physiology in many ways resembles the human physiology, it also has a relatively short generation time, low breeding and maintenance costs, and is available in a wide variety of inbred strains. The ability to genetically modify mouse embryonic stem cells to generate mouse models that better mimic human disease is another advantage. In the present study, a comprehensive phenotypic screening protocol is applied to elucidate the phenotype of a novel mouse knockout model of hepatocyte nuclear factor (HNF) 4-gamma. HNF4-gamma is expressed in the kidneys, gut, pancreas, and testis. The first level of the screen is aimed at general health, morphologic appearance, normal cage behaviour, and gross neurological functions. The second level of the screen looks at metabolic characteristics and lung function. The third level of the screen investigates behaviour more in-depth and the fourth level consists of a thorough pathological characterisation, blood chemistry, haematology, and bone marrow analysis. When compared with littermate wild-type mice (HNF4-gamma(+/+)), the HNF4-gamma knockout (HNF4-gamma(-/-)) mice had lowered energy expenditure and locomotor activity during night time that resulted in a higher body weight despite having reduced intake of food and water. HNF4-gamma(-/-) mice were less inclined to build nest and were found to spend more time in a passive state during the forced swim test.


Assuntos
Fator 4 Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/metabolismo , Animais , Comportamento Animal , Peso Corporal , Medula Óssea/metabolismo , Calorimetria , Feminino , Fator 4 Nuclear de Hepatócito/química , Heterozigoto , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Genéticos , Consumo de Oxigênio , Fenótipo
10.
Biochem Biophys Res Commun ; 348(2): 359-66, 2006 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-16887097

RESUMO

Obesity has been proposed to be a result of an imbalance in the physiological system that controls and maintains the body energy homeostasis. Several G-protein coupled receptors (GPCRs) are involved in the regulation of energy homeostasis. To investigate the importance of GPCR12, mice deficient of this receptor (GPCR12 KO) were studied regarding metabolism. Expression of GPCR12 was found primarily in the limbic and sensory systems, indicating its possible involvement in motivation, emotion together with various autonomic functions, and sensory information processing. GPCR12 KO mice were found to have higher body weight, body fat mass, lower respiratory exchange ratio (RER), hepatic steatosis, and were dyslipidemic. Neither food intake nor energy in faeces was affected in the GPCR12 KO mice. However, lower energy expenditure was found in the GPCR12 KO mice, which may explain the obesity. In conclusion, GPCR12 is considered important for the energy balance since GPCR12 KO mice develop obesity and have lower energy expenditure. This may be important for future drugs that target this receptor.


Assuntos
Dislipidemias/etiologia , Obesidade/genética , Receptores Acoplados a Proteínas G/deficiência , Animais , Glicemia/metabolismo , Composição Corporal , Peso Corporal , Proteínas de Transporte/biossíntese , Colesterol/sangue , Dislipidemias/genética , Ingestão de Alimentos , Metabolismo Energético , Feminino , Canais Iônicos , Masculino , Proteínas de Membrana/biossíntese , Camundongos , Camundongos Knockout , Proteínas Mitocondriais , Triglicerídeos/metabolismo , Proteína Desacopladora 1
11.
Diabetes ; 55(3): 725-33, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16505236

RESUMO

The hypothalamic peptide melanin-concentrating hormone (MCH) plays important roles in energy homeostasis. Animals overexpressing MCH develop hyperphagia, obesity, and insulin resistance. In this study, mice lacking both the MCH receptor-1 (MCHr1 knockout) and leptin (ob/ob) double-null mice (MCHr1 knockout ob/ob) were generated to investigate whether the obesity and/or the insulin resistance linked to the obese phenotype of ob/ob mice was attenuated by ablation of the MCHr1 gene. In MCHr1 knockout ob/ob mice an oral glucose load resulted in a lower blood glucose response and markedly lower insulin levels compared with the ob/ob mice despite no differences in body weight, food intake, or energy expenditure. In addition, MCHr1 knockout ob/ob mice had higher locomotor activity and lean body mass, lower body fat mass, and altered body temperature regulation compared with ob/ob mice. In conclusion, MCHr1 is important for insulin sensitivity and/or secretion via a mechanism not dependent on decreased body weight.


Assuntos
Peso Corporal , Resistência à Insulina , Leptina/deficiência , Obesidade/metabolismo , Receptores de Somatostatina/fisiologia , Animais , Composição Corporal , Regulação da Temperatura Corporal , Hormônio Liberador da Corticotropina/análise , Ingestão de Alimentos , Glucose/metabolismo , Camundongos , Camundongos Obesos , Atividade Motora , RNA Mensageiro/análise , Receptores para Leptina , Receptores de Somatostatina/deficiência , Estearoil-CoA Dessaturase/genética
12.
Am J Physiol Endocrinol Metab ; 290(2): E317-25, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16174655

RESUMO

We have previously shown that growth hormone (GH) overexpression in the brain increased food intake, accompanied with increased hypothalamic agouti-related protein (AgRP) expression. Ghrelin, which stimulates both appetite and GH secretion, was injected intracerebroventricularly to GHR-/- and littermate control (+/+) mice to determine whether ghrelin's acute effects on appetite are dependent on GHR signaling. GHR-/- mice were also analyzed with respect to serum levels of lipoproteins, apolipoprotein (apo)B, leptin, glucose, and insulin as well as body composition. Central injection of ghrelin into the third dorsal ventricle increased food consumption in +/+ mice, whereas no change was observed in GHR-/- mice. After ghrelin injection, AgRP mRNA expression in the hypothalamus was higher in +/+ littermates than in GHR-/- mice, indicating a possible importance of AgRP in the GHR-mediated effect of ghrelin. Compared with controls, GHR-/- mice had increased food intake, leptin levels, and total and intra-abdominal fat mass per body weight and deceased lean mass. Moreover, serum levels of triglycerides, LDL and HDL cholesterol, and apoB, as well as glucose and insulin levels were lower in the GHR-/- mice. In summary, ghrelin's acute central action to increase food intake requires functionally intact GHR signaling. Long-term GHR deficiency in mice is associated with high plasma leptin levels, obesity, and increased food intake but a marked decrease in all lipoprotein fractions.


Assuntos
Comportamento Alimentar/efeitos dos fármacos , Hipolipoproteinemias/induzido quimicamente , Hipolipoproteinemias/fisiopatologia , Obesidade/induzido quimicamente , Obesidade/fisiopatologia , Hormônios Peptídicos/administração & dosagem , Receptores da Somatotropina/deficiência , Animais , Peso Corporal/efeitos dos fármacos , Feminino , Grelina , Injeções , Masculino , Camundongos , Camundongos Knockout
13.
Bone ; 36(4): 607-16, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15780976

RESUMO

Mice deficient for all known thyroid hormone receptors, TRalpha1-/-beta-/- mice, display a clear skeletal phenotype characterized by growth retardation, delayed maturation of long bones and decreased trabecular and total bone mineral density (BMD; -14.6 +/- 2.8%, -14.4 +/- 1.5%). The aim of the present study was to investigate the molecular mechanisms behind the skeletal phenotype in TRalpha1-/-beta-/- mice. Global gene expression analysis was performed on total vertebrae from wild-type (WT) and TRalpha1-/-beta-/- mice using DNA microarray and the results were verified by real-time PCR. The mRNA levels of six genes (AdipoQ, Adipsin, Fat-Specific Protein 27 (FSP 27), lipoprotein lipase (LPL), retinol-binding protein (RBP) and phosphoenolpyruvate carboxykinase (PEPCK)) expressed by mature adipocytes were increased in TRalpha1-/-beta-/- compared with WT mice. An increased amount of fat (225% over WT) due to an increased number but unchanged mean size of adipocytes in the bone marrow of TRalpha1-/-beta-/- mice was revealed. Interestingly, the mRNA levels of the key regulator of osteoclastogenesis, receptor activator of NF-varkappab ligand (RANKL), were dramatically decreased in TRalpha1-/-beta-/- mice. In conclusion, TRalpha1-/-beta-/- mice demonstrated increased expression of adipocyte specific genes and an increased amount of bone marrow fat. Thus, these mice have increased adipogenesis in bone marrow associated with decreased trabecular bone mineral density (BMD). One may speculate that these effects either could be caused by an imbalance in the differentiation of the osteoblast and the adipocyte lineages at the expense of osteoblastogenesis, or by independent effects on the regulation of both osteoblastogenesis and adipogenesis.


Assuntos
Adipócitos/citologia , Composição Corporal , Densidade Óssea , Medula Óssea/metabolismo , Receptores dos Hormônios Tireóideos/fisiologia , Adipócitos/metabolismo , Adiponectina , Animais , Sequência de Bases , Fator D do Complemento , Primers do DNA , Peptídeos e Proteínas de Sinalização Intercelular/genética , Lipase Lipoproteica/genética , Camundongos , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , Fosfoenolpiruvato Carboxiquinase (ATP)/genética , RNA Mensageiro/genética , Receptores dos Hormônios Tireóideos/genética , Proteínas de Ligação ao Retinol/genética , Serina Endopeptidases/genética
14.
Endocrinology ; 146(2): 920-30, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15539551

RESUMO

It is known that bovine GH (bGH) transgenic mice have increased body mass, insulin resistance, and altered lipoprotein metabolism when fed a normal diet (ND). In this study, the effects of 8 wk of high-fat diet (HFD) were investigated in 6-month-old male bGH mice. Although littermate controls had unchanged energy intake, energy intake was higher in the bGH mice on a HFD than on a low-fat diet. Nevertheless, the bGH mice were resistant to diet-induced weight gain, and only in the bGH mice did the HFD result in increased energy expenditure. Glucose oxidation was higher in the bGH mice compared with littermate controls on both a HFD and ND. In addition, the bGH mice had 0.5 C higher body temperature throughout the day and increased hepatic uncoupling protein 2 expression; changes that were unaffected by the HFD. On a HFD, the effect of bGH overexpression on serum triglycerides and apolipoprotein B was opposite to that on a ND, resulting in higher serum concentrations of triglycerides and apolipoprotein B compared with littermate controls. Increased serum triglycerides were explained by decreased triglyceride clearance. The HFD led to diabetes only in the bGH mice. In conclusion, bGH transgenic mice were resistant to diet-induced obesity despite hyperphagia, possibly due to increased energy expenditure. On a HFD, bGH mice became dyslipidemic and diabetic and thereby more accurately reflect the metabolic situation in acromegalic patients.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Hormônio do Crescimento/genética , Hiperlipidemias/fisiopatologia , Hiperfagia/fisiopatologia , Obesidade/fisiopatologia , Acromegalia/metabolismo , Acromegalia/fisiopatologia , Animais , Composição Corporal , Temperatura Corporal , Proteínas de Transporte/genética , Bovinos , Diabetes Mellitus Experimental/metabolismo , Gorduras na Dieta/farmacologia , Ingestão de Alimentos , Metabolismo Energético/fisiologia , Teste de Tolerância a Glucose , Hiperlipidemias/metabolismo , Hiperfagia/metabolismo , Canais Iônicos , Lipídeos/sangue , Lipoproteínas/sangue , Proteínas de Membrana/genética , Proteínas de Membrana Transportadoras/genética , Camundongos , Camundongos Transgênicos , Proteínas Mitocondriais/genética , Obesidade/metabolismo , Consumo de Oxigênio/fisiologia , Proteína Desacopladora 1 , Proteína Desacopladora 2
15.
Biochem Biophys Res Commun ; 326(4): 759-65, 2005 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-15607734

RESUMO

The hypothalamic peptide melanin-concentrating hormone (MCH) and the gastric hormone ghrelin take part in the regulation of energy homeostasis and stimulate food intake. In the present study, ghrelin was administered centrally to MCH-receptor knockout (MCHr KO) mice. MCHr KO mice and wild type (WT) controls both consumed more food when treated with ghrelin. After ghrelin administration, the serum levels of insulin increased only in WT mice whereas the serum levels of corticosterone increased both in WT and MCHr KO mice. The level of growth hormone (GH) mRNA in the pituitary gland was markedly increased in response to ghrelin injection in the WT mice but was unaffected in the MCHr KO mice. The different ghrelin responses could not be explained by a difference in growth hormone secretagogue receptor expression between MCHr KO and WT mice in the pituitary or hypothalamus. In summary, the MCHr is not required for ghrelin induced feeding. However, the MCHr does play a role for the effect of ghrelin on GH expression in the pituitary and serum insulin levels.


Assuntos
Corticosterona/sangue , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Insulina/sangue , Hormônios Peptídicos/farmacologia , Hipófise/metabolismo , Receptores do Hormônio Hipofisário/metabolismo , Animais , Grelina , Hormônio do Crescimento/metabolismo , Camundongos , Camundongos Knockout , Hipófise/efeitos dos fármacos , Receptores do Hormônio Hipofisário/deficiência
16.
Diabetes ; 54(1): 51-62, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15616010

RESUMO

It is well known that peripherally administered growth hormone (GH) results in decreased body fat mass. However, GH-deficient patients increase their food intake when substituted with GH, suggesting that GH also has an appetite stimulating effect. Transgenic mice with an overexpression of bovine GH in the central nervous system (CNS) were created to investigate the role of GH in CNS. This study shows that overexpression of GH in the CNS differentiates the effect of GH on body fat mass from that on appetite. The transgenic mice were not GH-deficient but were obese and showed increased food intake as well as increased hypothalamic expression of agouti-related protein and neuropeptide Y. GH also had an acute effect on food intake following intracerebroventricular injection of C57BL/6 mice. The transgenic mice were severely hyperinsulinemic and showed a marked hyperplasia of the islets of Langerhans. In addition, the transgenic mice displayed alterations in serum lipid and lipoprotein levels and hepatic gene expression. In conclusion, GH overexpression in the CNS results in hyperphagia-induced obesity indicating a dual effect of GH with a central stimulation of appetite and a peripheral lipolytic effect.


Assuntos
Hormônio do Crescimento/genética , Hiperlipidemias/genética , Hiperfagia/genética , Resistência à Insulina/genética , Obesidade/etiologia , Tecido Adiposo/anatomia & histologia , Animais , Sequência de Bases , Glicemia/metabolismo , Peso Corporal , Calorimetria Indireta , Bovinos , Sondas de DNA , Ingestão de Energia/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/fisiologia , Genoma , Hormônio do Crescimento/administração & dosagem , Hormônio do Crescimento/farmacologia , Hormônio do Crescimento/fisiologia , Hiperinsulinismo/induzido quimicamente , Hiperfagia/sangue , Hiperfagia/fisiopatologia , Hipotálamo/fisiologia , Injeções Intraventriculares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Obesidade/sangue
17.
Am J Physiol Regul Integr Comp Physiol ; 287(4): R749-58, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15130877

RESUMO

Melanin-concentrating hormone (MCH) plays an important role in energy balance. The current studies were carried out on a new line of mice lacking the rodent MCH receptor (MCHR1(-/-) mice). These mice confirmed the previously reported lean phenotype characterized by increased energy expenditure and modestly increased caloric intake. Because MCH is expressed in the lateral hypothalamic area, which also has an important role in the regulation of the autonomic nervous system, heart rate and blood pressure were measured by a telemetric method to investigate whether the increased energy expenditure in these mice might be due to altered autonomic nervous system activity. Male MCHR1(-/-) mice demonstrated a significantly increased heart rate [24-h period: wild type 495 +/- 4 vs. MCHR1(-/-) 561 +/- 8 beats/min (P < 0.001); dark phase: wild type 506 +/- 8 vs. MCHR1(-/-) 582 +/- 9 beats/min (P < 0.001); light phase: wild type 484 +/- 13 vs. MCHR1(-/-) 539 +/- 9 beats/min (P < 0.005)] with no significant difference in mean arterial pressure [wild type 110 +/- 0.3 vs. MCHR1(-/-) 113 +/- 0.4 mmHg (P > 0.05)]. Locomotor activity and core body temperature were higher in the MCHR1(-/-) mice during the dark phase only and thus temporally dissociated from heart rate differences. On fasting, wild-type animals rapidly downregulated body temperature and heart rate. MCHR1(-/-) mice displayed a distinct delay in the onset of this downregulation. To investigate the mechanism underlying these differences, autonomic blockade experiments were carried out. Administration of the adrenergic antagonist metoprolol completely reversed the tachycardia seen in MCHR1(-/-) mice, suggesting an increased sympathetic tone.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Frequência Cardíaca/genética , Frequência Cardíaca/fisiologia , Receptores do Hormônio Hipofisário/genética , Receptores do Hormônio Hipofisário/fisiologia , Tecido Adiposo/fisiologia , Animais , Sistema Nervoso Autônomo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/genética , Pressão Sanguínea/fisiologia , Composição Corporal/genética , Composição Corporal/fisiologia , Temperatura Corporal/genética , Temperatura Corporal/fisiologia , Peso Corporal/genética , Peso Corporal/fisiologia , Calorimetria Indireta , Clonagem Molecular , Ingestão de Alimentos/genética , Ingestão de Alimentos/fisiologia , Metabolismo Energético/genética , Metabolismo Energético/fisiologia , Jejum/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Atividade Motora/genética , Atividade Motora/fisiologia , Parassimpatolíticos/farmacologia , Simpatolíticos/farmacologia
18.
Biochem Biophys Res Commun ; 318(4): 964-9, 2004 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-15147966

RESUMO

It is well recognized that the hypothalamus is of central importance in the regulation of food intake and fat mass. Recent studies indicate that it also plays an important role in the regulation of bone mass. Melanin concentrating hormone (MCH) is highly expressed in the hypothalamus and has been implicated in regulation of energy homeostasis. We developed MCHR1 inactivated mice to evaluate the physiological role of this receptor. Interestingly, the MCHR1(-/-) mice have osteoporosis, caused by a reduction in the cortical bone mass, while the amount of trabecular bone is unaffected. The reduction in cortical bone mass is due to decreased cortical thickness. Serum levels of c-telopeptide, a marker of bone resorption, are increased in MCHR1(-/-) mice, indicating that the MCHR1(-/-) mice have a high bone turnover osteoporosis. In conclusion, the MCHR1(-/-) mice have osteoporosis, indicating that MCHR1-signalling is involved in a tonic stimulation of bone mass.


Assuntos
Osteoporose/metabolismo , Receptores do Hormônio Hipofisário/deficiência , Receptores do Hormônio Hipofisário/fisiologia , Absorciometria de Fóton , Animais , Biomarcadores/sangue , Densidade Óssea/fisiologia , Reabsorção Óssea/sangue , Colágeno/sangue , Colágeno Tipo I , Feminino , Fêmur/química , Fêmur/diagnóstico por imagem , Fêmur/patologia , Componentes do Gene , Expressão Gênica , Hormônios Hipotalâmicos/metabolismo , Masculino , Melaninas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteocalcina/sangue , Osteoporose/sangue , Osteoporose/genética , Peptídeos/sangue , Hormônios Hipofisários/metabolismo , RNA Mensageiro/biossíntese , Receptores do Hormônio Hipofisário/genética , Distribuição Tecidual
19.
Nature ; 429(6990): 417-23, 2004 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-15164064

RESUMO

Point mutations and deletions of mitochondrial DNA (mtDNA) accumulate in a variety of tissues during ageing in humans, monkeys and rodents. These mutations are unevenly distributed and can accumulate clonally in certain cells, causing a mosaic pattern of respiratory chain deficiency in tissues such as heart, skeletal muscle and brain. In terms of the ageing process, their possible causative effects have been intensely debated because of their low abundance and purely correlative connection with ageing. We have now addressed this question experimentally by creating homozygous knock-in mice that express a proof-reading-deficient version of PolgA, the nucleus-encoded catalytic subunit of mtDNA polymerase. Here we show that the knock-in mice develop an mtDNA mutator phenotype with a threefold to fivefold increase in the levels of point mutations, as well as increased amounts of deleted mtDNA. This increase in somatic mtDNA mutations is associated with reduced lifespan and premature onset of ageing-related phenotypes such as weight loss, reduced subcutaneous fat, alopecia (hair loss), kyphosis (curvature of the spine), osteoporosis, anaemia, reduced fertility and heart enlargement. Our results thus provide a causative link between mtDNA mutations and ageing phenotypes in mammals.


Assuntos
Senilidade Prematura/enzimologia , Senilidade Prematura/genética , DNA Polimerase Dirigida por DNA/genética , DNA Polimerase Dirigida por DNA/metabolismo , Mitocôndrias/enzimologia , Mutagênese/genética , Mutação/genética , Tecido Adiposo , Senilidade Prematura/complicações , Senilidade Prematura/patologia , Alopecia/complicações , Alopecia/enzimologia , Alopecia/genética , Animais , Composição Corporal , Peso Corporal , Densidade Óssea/genética , Análise Mutacional de DNA , DNA Polimerase gama , DNA Mitocondrial/genética , Homozigoto , Cifose/complicações , Cifose/enzimologia , Cifose/genética , Camundongos , Fenótipo , Transgenes/genética
20.
Endocrinology ; 144(11): 4955-66, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12960074

RESUMO

The probasin (Pb)-PRL transgenic mice that overexpress the rat PRL gene specifically in the prostate develop a dramatic enlargement of the prostate gland. The objective of this study was to characterize the molecular mechanisms involved in the prostate hyperplasia seen in the Pb-PRL transgenic mice. cDNA microarray analysis was used to identify differentially expressed transcripts in the hyperplastic prostates of 6-month-old transgenic mice compared with age-matched controls. We report the identification of 266 genes (175 up-regulated and 91 down-regulated) that were differentially expressed in the enlarged transgenic prostates compared with controls. Subsequential real-time RT-PCR was used to verify a set of differentially regulated transcripts. The hyperplastic prostates of Pb-PRL transgenic mice demonstrate a molecular pattern supporting the importance of reduced degree of apoptosis for the development of the phenotype. Immunohistochemical analysis of apoptotic activity using two different markers of apoptosis (single-stranded DNA and activated caspase-3) were performed, and the results showed diminished apoptosis activity in the prostate of Pb-PRL transgenic mice compared with control prostates. The increased stromal/epithelial ratio of the Pb-PRL transgenic prostate together with up-regulation of a significant fraction of genes involved in tissue remodeling activity, including the synthesis and degradation of the extracellular matrix and changes in protease activity, suggest that activation of the stroma is involved in the development of prostate hyperplasia. Overall, the differentially expressed transcripts identified in this study show many molecular similarities between the prostate hyperplasia of PRL-transgenic mice and human prostate pathology, including both benign prostatic hyperplasia and prostate cancer.


Assuntos
Expressão Gênica , Prolactina/genética , Próstata/metabolismo , Hiperplasia Prostática/metabolismo , Proteína de Ligação a Androgênios/genética , Animais , Apoptose , Sistemas Computacionais , Regulação para Baixo , Perfilação da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Análise de Sequência com Séries de Oligonucleotídeos , Hiperplasia Prostática/genética , Hiperplasia Prostática/fisiopatologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
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