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1.
FASEB J ; 38(10): e23690, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38795327

RESUMO

Alterations to gene transcription and DNA methylation are a feature of many liver diseases including fatty liver disease and liver cancer. However, it is unclear whether the DNA methylation changes are a cause or a consequence of the transcriptional changes. It is even possible that the methylation changes are not required for the transcriptional changes. If DNA methylation is just a minor player in, or a consequence of liver transcriptional change, then future studies in this area should focus on other systems such as histone tail modifications. To interrogate the importance of de novo DNA methylation, we generated mice that are homozygous mutants for both Dnmt3a and Dnmt3b in post-natal liver. These mice are viable and fertile with normal sized livers. Males, but not females, showed increased adipose depots, yet paradoxically, improved glucose tolerance on both control diet and high-fat diets (HFD). Comparison of the transcriptome and methylome with RNA sequencing and whole-genome bisulfite sequencing in adult hepatocytes revealed that widespread loss of methylation in CpG-rich regions in the mutant did not induce loss of homeostatic transcriptional regulation. Similarly, extensive transcriptional changes induced by HFD did not require de novo DNA methylation. The improved metabolic phenotype of the Dnmt3a/3b mutant mice may be mediated through the dysregulation of a subset of glucose and fat metabolism genes which increase both glucose uptake and lipid export by the liver. However, further work is needed to confirm this.


Assuntos
DNA (Citosina-5-)-Metiltransferases , Metilação de DNA , DNA Metiltransferase 3A , DNA Metiltransferase 3B , Dieta Hiperlipídica , Intolerância à Glucose , Fígado , Animais , Masculino , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Camundongos , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A/metabolismo , Intolerância à Glucose/metabolismo , Intolerância à Glucose/genética , Feminino , Camundongos Endogâmicos C57BL
2.
Front Neuroendocrinol ; 56: 100818, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31843506

RESUMO

The consolidation of long-term memory is influenced by various neuromodulators. One of these is estradiol, a steroid hormone that is synthesized both in peripheral endocrine tissue and in the brain, including the hippocampus. Here, we examine the evidence regarding the role of estradiol in the hippocampus, specifically, in memory formation and its effects on the molecular mechanisms underlying synaptic plasticity. We conclude that estradiol improves memory consolidation and, thereby, long-term memory. Previous studies have shown that it does this in three, interconnected ways: (1) via functional changes in excitatory activity, (2) signaling changes in calcium dynamics, protein phosphorylation and protein expression, and (3) structural changes to synaptic morphology. Through a functional network analysis of proteins affected by estradiol, we identify potential protein-protein interactions that further support a role for estradiol in modulating synaptic plasticity as well as highlight signaling pathways that may be involved in these changes within the hippocampus.


Assuntos
Estradiol/fisiologia , Hipocampo/fisiologia , Memória/fisiologia , Plasticidade Neuronal/fisiologia , Adulto , Animais , Estradiol/farmacologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Hipocampo/efeitos dos fármacos , Humanos , Masculino , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Fosforilação/fisiologia , Ratos , Receptores de Estrogênio/fisiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Potenciais Sinápticos/efeitos dos fármacos , Potenciais Sinápticos/fisiologia
3.
Ann Oncol ; 31(7): 930-941, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32289380

RESUMO

BACKGROUND: We have shown previously in multivariable analysis that black men had 19% lower risk of death than white men with metastatic castration-resistant prostate cancer (mCRPC) treated with a docetaxel and prednisone (DP)-based regimen. The primary goal of this analysis was to compare progression-free survival (PFS), biochemical PFS, ≥50% decline in prostate-specific antigen (PSA) from baseline and objective response rate (ORR) in white, black and Asian men with mCRPC treated with a DP-based regimen. PATIENTS AND METHODS: Individual patient data from 8820 mCRPC men randomized on nine phase III trials to a DP-containing regimen were combined. Race used in the analysis was based on self-report. End points were PFS, biochemical PSA, ≥50% decline in PSA from baseline and ORR. The proportional hazards and the logistic regression models were employed to assess the prognostic importance of race in predicting outcomes adjusting for established prognostic factors. RESULTS: Of 8820 patients, 7528 (85%) were white, 500 (6%) were black, 424 were Asian (5%) and 368 (4%) had race unspecified. Median PFS were 8.3 [95% confidence interval (CI) 8.2-8.5], 8.2 (95% CI 7.4-8.8) and 8.3 (95% CI 7.6-8.8) months in white, black and Asian men, respectively. Median PSA PFS were 9.9 (95% CI 9.7-10.4), 8.5 (95% CI 8.0-10.3) and 11.1 (95% CI 9.9-12.5) months in white, black and Asian men, respectively. CONCLUSIONS: We observed no differences in clinical outcomes by race and ethnic groups in men with mCRPC enrolled on these phase III clinical trials with DP.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Intervalo Livre de Doença , Docetaxel/uso terapêutico , Etnicidade , Humanos , Masculino , Prednisona/uso terapêutico , Antígeno Prostático Específico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Estudos Retrospectivos , Resultado do Tratamento
4.
Mol Psychiatry ; 23(2): 351-361, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28289278

RESUMO

The western diet is known to have detrimental effects on cognition and the gut microbiota, but few studies have investigated how these may be related. Here, we examined whether a probiotic could prevent diet-induced memory deficits. Rats were pre-exposed to vehicle, low or high doses of VSL#3 for 2 weeks before half were switched from chow to a cafeteria diet (Caf) for 25 days; VSL#3 treatment continued until death. High-dose VSL#3 prevented the diet-induced memory deficits on the hippocampal-dependent place task, but the probiotic caused deficits on the perirhinal-dependent object task, irrespective of diet or dose. No differences were observed in anxiety-like behaviour on the elevated plus maze. Gut microbial diversity was dramatically decreased by Caf diet and here, VSL#3 was able to increase the abundance of some taxa contained in the probiotic such as Streptococcus and Lactobacillus and also other taxa including Butyrivibrio, which were decreased by the Caf diet. This affected the predicted profile of microbial metabolic pathways related to antioxidant and bile biosynthesis, and fat and carbohydrate metabolism. In the hippocampus, the Caf diet increased the expression of many genes related to neuroplasticity and serotonin receptor (5HT) 1A, which was normalised in Caf-High rats. Distance-based linear modelling showed that these genes were the best predictors of place memory, and related to microbiota principal component (PC) 1. Neuroplasticity genes in the perirhinal cortex were also affected and related to PC1 but object memory performance was correlated with perirhinal 5HT2C expression and microbiota PC3. These results show that probiotics can be beneficial in situations of gut dysbiosis where memory deficits are evident but may be detrimental in healthy subjects.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Memória/efeitos dos fármacos , Probióticos/farmacologia , Animais , Cognição/fisiologia , Dieta , Dieta Ocidental/efeitos adversos , Microbioma Gastrointestinal/fisiologia , Hipocampo , Masculino , Memória/fisiologia , Transtornos da Memória/microbiologia , Plasticidade Neuronal/fisiologia , Ratos , Ratos Sprague-Dawley , Receptores de Serotonina/fisiologia , Serotonina/metabolismo
5.
Nutr Metab Cardiovasc Dis ; 25(9): 881-888, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26224356

RESUMO

BACKGROUND AND AIMS: Growing evidence suggests maternal obesity leads to adverse outcomes for offspring, including increased cardiovascular disease (CVD). Alterations in taste preferences of offspring from mothers consuming a high fat diet (HFD) have also been reported. Given recent reports describing cardiac taste receptors, we examined whether the expression of umami and bitter taste receptors is modulated by maternal obesity, and compared this with the physiological challenge of maternal exercise. METHODS AND RESULTS: Female Sprague-Dawley rats were fed chow (C) or HFD (F) and half of each were provided with a running wheel to enable voluntary exercise (CE or FE), the others remaining sedentary (CS or FS). Two pups from each mother were killed at postnatal day 19. Both lean and obese dams undertook similar amounts of exercise (8.1 ± 2.4 vs 5.1 ± 1.5 km). Maternal obesity increased offspring body weight, adiposity, net and weight-corrected heart ventricle weight, with no effect of exercise. Maternal obesity also increased offspring plasma leptin concentrations, which were normalised by maternal exercise. Cardiac ventricle mRNA expression of bitter taste receptors, ß-adrenoceptor (Adrbk1) and angiotensin II receptor type 1a (Agtr1a) were significantly decreased in response to maternal obesity, with maternal exercise decreasing Agtr1a in FE offspring. No changes in umami receptors were observed. FTO mRNA expression was down-regulated by maternal HFD with an up-regulation in offspring of CE mothers. CONCLUSION: Maternal obesity affected the expression of bitter taste receptors and other genes in the heart ventricle, potentially implicating these genes in the development of CVD associated with maternal obesity.


Assuntos
Expressão Gênica , Ventrículos do Coração/metabolismo , Proteínas/genética , Adiposidade/fisiologia , Dioxigenase FTO Dependente de alfa-Cetoglutarato , Animais , Peso Corporal , Dieta , Dieta Hiperlipídica/efeitos adversos , Regulação para Baixo , Feminino , Leptina/sangue , Fenômenos Fisiológicos da Nutrição Materna , Obesidade , Condicionamento Físico Animal , Gravidez , Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Regulação para Cima
7.
Nutr Metab Cardiovasc Dis ; 23(6): 574-81, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22305126

RESUMO

AIM: Physical exercise reduces obesity, insulin resistance and dyslipidemia. We previously found that maternal obesity alters central appetite circuits and contributes to increased adiposity, glucose intolerance and metabolic disease in offspring. Here we hypothesized that voluntary exercise would ameliorate the adverse metabolic effects of maternal obesity on offspring. METHODS AND RESULTS: Sprague-Dawley females fed chow (C) or high-fat diet HFD (H) were mated. Female offspring from C dams were weaned onto chow (CC); those from H dams recieved chow (HC) or HFD (HH). Half of each group was provided with running wheels (CC(EX), HC(EX), HH(EX); n=10-12). Maternal obesity increased body weight (12%), adiposity, plasma lipids and induced glucose intolerance (HC vs CC; P<0.05). These were exaggerated by postweaning HFD (HH vs HC; P<0.01), showed doubled energy intake, a 37% increase in body weight, insulin resistance and glucose intolerance (HH vs HC; P<0.01). Exercise reduced fat mass, plasma lipids, HOMA and fasting glucose in HC(EX) (vs HC; P<0.05) and HH(EX) (vs HH; P<0.01). Values in HC(EX) were indistinguishable from CC, however in HH(EX) these metabolic parameters remained higher than the sedentary HC and CC rats (P<0.01). mRNA expression of hypothalamic pro-opiomelanocortin, and adipose tumour necrosis factor α and 11ß-hydroxysteroid dehydrogenase type 1 were reduced by exercise in HH(EX) (vs HH; P<0.05). CONCLUSION: While voluntary exercise almost completely reversed the metabolic effects of maternal obesity in chow fed offspring, it did not fully attenuate the increased adiposity, glucose intolerance and insulin resistance in offspring weaned onto HFD.


Assuntos
Homeostase/fisiologia , Fenômenos Fisiológicos da Nutrição Materna , Obesidade/metabolismo , Condicionamento Físico Animal/fisiologia , Desmame , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/sangue , Adiposidade , Fenômenos Fisiológicos da Nutrição Animal , Animais , Apetite/fisiologia , Glicemia/análise , Pressão Sanguínea , Peso Corporal , Dieta Hiperlipídica , Dislipidemias/metabolismo , Ingestão de Energia , Ácidos Graxos não Esterificados/sangue , Feminino , Hipotálamo/metabolismo , Insulina/sangue , Resistência à Insulina , Leptina/sangue , Pró-Opiomelanocortina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/sangue
8.
Ann Oncol ; 23(10): 2714-2719, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22553195

RESUMO

BACKGROUND: This first-in-human phase I/IIA study was designed to evaluate the safety and pharmacokinetics (PKs) of AGS-PSCA a fully human monoclonal antibody directed to prostate stem cell antigen (PSCA) in progressive castration-resistant prostate cancer. PATIENTS AND METHODS: Twenty-nine patients were administered infusions of AGS-PSCA (1-40 mg/kg) every 3 weeks for 12 weeks; 18 final patients received a 40-mg/kg loading dose followed by 20-mg/kg repeat doses. Primary end points were safety and PK. Immunogenicity, antitumor activity and circulating tumor cells were also evaluated. RESULTS: No drug-related serious adverse events were noted. Dose escalation stopped before reaching the maximum tolerated dose as target concentrations were achieved. Drug levels accumulated linearly with dose and the mean terminal half-life was 2-3 weeks across dose levels. The 40-mg/kg loading dose followed by repeated 20-mg/kg doses yielded serum drug concentrations above the projected minimum therapeutic threshold after two to three doses without excessive drug accumulation or toxicity. Significant antitumor effects were not seen. CONCLUSIONS: A 40-mg/kg loading dose followed by 20-mg/kg infusions every 3 weeks is the recommended phase II dose of AGS-PSCA. PSCA is a promising drug target and studies in prostate and other relevant solid tumors are planned.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígenos de Neoplasias/imunologia , Proteínas de Neoplasias/imunologia , Orquiectomia , Neoplasias da Próstata/terapia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacocinética , Proteínas Ligadas por GPI/imunologia , Meia-Vida , Humanos , Masculino , Células Neoplásicas Circulantes
9.
Nutr Metab Cardiovasc Dis ; 22(3): 269-76, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21208789

RESUMO

BACKGROUND AND AIMS: Maternal obesity and post-natal over-nutrition play an important role in programming glucose and lipid metabolism later in life. The aim of this study was to decipher the contributions of maternal obesity and post-natal over-nutrition on glucose and lipid metabolism in skeletal muscle. METHOD AND RESULTS: Male offspring of Sprague Dawley rat mothers fed either chow or high fat diet (HFD) for 5 weeks prior to mating were subsequently fed either chow or HFD until 18 weeks of age. Collection of plasma and skeletal muscle was performed at weaning (20 days) and 18 weeks. At weaning, offspring from obese mothers showed increased body weight, plasma insulin and lactate concentrations associated with reduced skeletal muscle glucose transporter 4 (GLUT4) and increased monocarboxylate transporter 1 (MCT1) protein. In 18-week old offspring, post-weaning HFD further exacerbated the elevated body weight caused by maternal obesity. Surprisingly this additive effect on body weight was not reflected in plasma glucose, insulin, lactate and MCT1; these markers were only increased by post-weaning HFD consumption. However, an additive effect of maternal obesity and post-weaning HFD led to decreased muscle GLUT4 levels, as well as mRNA levels of carnitine palmitoyl transferase-1, myogenic differentiation protein and myogenin. CONCLUSION: Post-weaning HFD exerted an additive effect to that of maternal obesity on body weight and skeletal muscle markers of glucose and lipid metabolism but not on plasma glucose and insulin levels, suggesting that maternal obesity and post-natal over-nutrition impair skeletal muscle function via different mechanisms.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Dieta Hiperlipídica , Metabolismo Energético , Músculo Esquelético/metabolismo , Obesidade/metabolismo , Hipernutrição/metabolismo , Efeitos Tardios da Exposição Pré-Natal , Fatores Etários , Animais , Peso Corporal , Feminino , Transportador de Glucose Tipo 4/metabolismo , Insulina/sangue , Ácido Láctico/sangue , Masculino , Transportadores de Ácidos Monocarboxílicos/metabolismo , Músculo Esquelético/fisiopatologia , Obesidade/fisiopatologia , Hipernutrição/fisiopatologia , Gravidez , Ratos , Ratos Sprague-Dawley , Simportadores/metabolismo , Desmame
10.
J Exp Med ; 169(3): 847-63, 1989 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2564414

RESUMO

Structural and quantitative polymorphisms have been described in human CR1. In the former, the S allotype is larger than the F allotype by 40-50 kD, the size of a long homologous repeat (LHR). In the latter, homozygotes for a 7.4-kb Hind III fragment express fourfold more CR1 per erythrocyte than do homozygotes for the allelic 6.9-kb restriction fragment. The basis for these genomic polymorphisms has been determined by restriction mapping the entire S allele and part of the F allele. The S allele is 158 kb and contains 5 LHRs of 20-30 kb, designated -A, -B/A, -B, -C, and -D, respectively, 5' to 3'. Extensive homology was found among the LHRs in their restriction maps, exon organization, and the coding and noncoding sequences. The presence of LHR-B/A in the S allele but not in the F allele accounts for the longer transcripts and polypeptide associated with the former allotype. At least 42 exons are present in the S allele, with distinct exons for the leader sequence, the transmembrane and cytoplasmic regions and most of the SCRs comprising the extracellular portion of CR1. Consistent with the mapping of the ligand binding site to the first two SCRs in each LHR, the second SCRs in LHR-A, -B/A, -B, and -C are encoded by two exons, reflecting a specialized function for this unit. The allelic 7.4/6.9-kb Hind III fragments extend from the 3' region of LHR-C to LHR-D. The 6.9-kb restriction fragment is the result of a new Hind III site generated by a single base change in the intron between the exons encoding the second SCR of LHR-D. A second cluster of genomic clones has been identified by hybridization to CR1 probes. Although they contain regions of hybridization to the cDNA and genomic probes derived from CR1, these cannot be overlapped with the structural gene owing to their distinct restriction maps. Three genomic polymorphisms previously identified by CR1 cDNA probes map to this region. These additional clones may represent part of a duplicated allele located nearby within the CR1 locus.


Assuntos
Alelos , Polimorfismo Genético , Receptores de Complemento/genética , Sequência de Aminoácidos , Sequência de Bases , Cosmídeos , Sondas de DNA , DNA Recombinante , Desoxirribonuclease BamHI , Desoxirribonuclease EcoRI , Desoxirribonuclease HindIII , Desoxirribonucleases de Sítio Específico do Tipo II , Éxons , Humanos , Íntrons , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Polimorfismo de Fragmento de Restrição , Receptores de Complemento 3b , Sequências Repetitivas de Ácido Nucleico , Homologia de Sequência do Ácido Nucleico
11.
Nutr Metab Cardiovasc Dis ; 20(1): 49-55, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19361967

RESUMO

BACKGROUND AND AIMS: Given the recent observation of a local renin-angiotensin system (RAS) in adipose tissue, and its association with obesity-related hypertension, the metabolic effects of treatment with a low dose angiotensin converting enzyme inhibitor (ACEI) were investigated in a rodent model of diet-induced obesity. METHODS AND RESULTS: Male Sprague Dawley rats were exposed to either standard laboratory chow (12% calories as fat) or palatable high fat (30% calories as fat) diet for 12 weeks. A subset from both dietary groups was given low dose ACEI in drinking water (perindopril, 0.3 mg/kg/day) throughout the study. The high fat diet increased body weight, adiposity, circulating leptin and insulin and in the liver we observed fat accumulation and increased tissue ACE activity. Treatment with perindopril decreased food intake and circulating insulin in both diet groups, and hepatic ACE activity in high fat fed animals only. Decreased plasma leptin concentration with ACE inhibition was only evident in chow fed animals. These effects were independent of any blood pressure lowering effect of ACE inhibition. CONCLUSION: Chronic low dose ACEI treatment reduced circulating insulin and leptin levels with some reduction in food intake in chow fed rats. Fewer beneficial effects were observed in obesity, and further work is required to investigate higher ACEI doses. Our data suggest a reduction in hepatic ACE activity may affect lipid accumulation and other inflammatory responses, as well as improving insulin resistance. Our findings may have implications for maximizing the clinical benefit of ACEI in patients without overt cardiovascular complications.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Dieta , Metabolismo Energético/efeitos dos fármacos , Obesidade/metabolismo , Perindopril/farmacologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/patologia , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , Glicemia/análise , Glicemia/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Gorduras na Dieta/administração & dosagem , Ingestão de Energia/efeitos dos fármacos , Insulina/sangue , Leptina/sangue , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Obesidade/sangue , Obesidade/tratamento farmacológico , Obesidade/patologia , Tamanho do Órgão/efeitos dos fármacos , Peptidil Dipeptidase A/metabolismo , Perindopril/administração & dosagem , Perindopril/uso terapêutico , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
12.
Reprod Domest Anim ; 45(1): 109-17, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18992112

RESUMO

The objectives of the present study were to quantify the effects of a biological chronic stressor (lameness) on the duration and frequency of different oestrous behaviours in parallel with milk hormone profiles. Dairy cows 51.8 +/- 1.4 days postpartum (n = 59), including 18 non-lame control cows, were scored for lameness and closely observed for signs of oestrus having had their follicular phases synchronized by administration of gonadotrophin-releasing-hormone (GnRH) followed by prostaglandin F(2alpha) (PG) 7 days later. Lameness shortened the period when herd-mates attempted to mount the lame cows (1.83 +/- 0.69 h vs 5.20 +/- 1.53 h; p = 0.042) but did not affect the overall duration of total behaviours (lame 12.3 +/- 1.3 h vs non-lame 15.2 +/- 1.3 h). Lameness also lowered the intensity of oestrus [1417 +/- 206 points (n = 18) vs 2260 +/- 307 points (n = 15); p = 0.029]. Throughout the synchronized oestrous period, lame cows mounted the rear of herd-mates less frequently (p = 0.020) and tended to chin rest less (p = 0.075). Around the period of maximum oestrous intensity, lameness also diminished the proportion of cows mounting the rear of another cow and chin resting (p = 0.048, p = 0.037, respectively). Furthermore, lame cows had lower progesterone values during the 6 days before oestrous (p < or = 0.05). Fewer lame cows were observed in oestrus following PG (non-lame 83%, lame 53%; p = 0.030); however, if prior progesterone concentrations were elevated, lame cows were just as likely to be observed in oestrus. In conclusion, following endogenous progesterone exposure, lameness shortens the period when herd-mates attempt to mount lame cows but does not affect the incidence of oestrous. However, lame cows are mounted less frequently and express oestrus of lower intensity. This is associated with lower progesterone prior to oestrus but not with abnormal oestradiol or cortisol profiles in daily milk samples.


Assuntos
Doenças dos Bovinos/fisiopatologia , Estradiol/análise , Coxeadura Animal/fisiopatologia , Leite/química , Progesterona/análise , Comportamento Sexual Animal/fisiologia , Animais , Bovinos , Estradiol/sangue , Estro/fisiologia , Feminino , Hidrocortisona/análise , Hidrocortisona/sangue , Progesterona/sangue
13.
Int J Obes (Lond) ; 33(1): 115-22, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18982008

RESUMO

OBJECTIVE: Key appetite regulators and their receptors are already present in the fetal hypothalamus, and may respond to hormones such as leptin. Intrauterine food restriction or hyperglycemia can reprogram these circuits, possibly predisposing individuals to adverse health outcomes in adulthood. Given the global obesity epidemic, maternal overweight and obesity is becoming more prevalent. Earlier, we observed rapid growth of pups from obese dams during the suckling period. However, it is unclear whether this is because of alterations in leptin and hypothalamic appetite regulators at birth. DESIGN: Female Sprague-Dawley rats were fed palatable high-fat diet (HFD) or chow for 5 weeks to induce obesity before mating. The same diet continued during gestation. At day 1, after birth, plasma and hypothalamus were collected from male and female pups. MEASUREMENTS: Body weight and organ mass were recorded. Leptin and insulin levels were measured in the plasma by radioimmunoassay. Hypothalamic mRNA expression of neuropeptide-Y (NPY), pro-opiomelanocortin, leptin receptor and its downstream signal, STAT3 (signal transducer and activator of transcription 3), were measured using real-time PCR. RESULTS: Body and organ weights of pups from obese dams were similar to those from lean dams, across both genders. However, plasma leptin levels were significantly lower in offspring from obese dams (male: 0.53+/-0.13 vs 1.05+/-0.21 ng ml(-1); female: 0.33+/-0.09 vs 2.12+/-0.57 ng ml(-1), respectively; both P<0.05). Hypothalamic mRNA expression of NPY, pro-opiomelanocortin, leptin receptor and STAT3 were also significantly lower in pups from obese dams. CONCLUSION: Long-term maternal obesity, together with lower leptin levels in pups from obese dams may contribute to the lower expression of key appetite regulators on day 1 of life, suggesting altered intrauterine neuron development in response to intrauterine overnutrition, which may contribute to eating disorders later in life.


Assuntos
Animais Recém-Nascidos/metabolismo , Regulação do Apetite , Hipotálamo/metabolismo , Leptina/sangue , Fenômenos Fisiológicos da Nutrição Materna , Obesidade/metabolismo , Proteína Relacionada com Agouti/análise , Proteína Relacionada com Agouti/genética , Animais , Biomarcadores/análise , Feminino , Hipotálamo/química , Insulina/sangue , Masculino , Neuropeptídeo Y/análise , Neuropeptídeo Y/genética , Gravidez , Pró-Opiomelanocortina/análise , Pró-Opiomelanocortina/genética , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Receptores para Leptina/análise , Fator de Transcrição STAT3/análise , Fator de Transcrição STAT3/genética , Transdução de Sinais/fisiologia
14.
Theriogenology ; 71(5): 801-6, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19059637

RESUMO

The objective of this study was to investigate the effect of somatic cell count (SCC), body condition score (BCS) or lameness score on ovarian follicular growth and ovulation in dairy cows. Seventy four animals 30-80 days post-partum were monitored for all three conditions before synchronization of ovarian follicular phases by administration of gonadotrophin releasing hormone (GnRH) followed seven days later with prostaglandin F2alpha (PG). Ultrasonography of both ovaries twice daily throughout the follicular phase revealed that fewer animals with combined high SCC and lameness (4/9) ovulated compared to healthy animals (19/21; P=0.006) or animals with only high SCC (11/11; P=0.004) or only lameness (21/27; P=0.06). Overall, regardless of the presence of other concurrent conditions, fewer lame cows ovulated than Non Lame animals (30/42 and 30/32; P=0.015). Mean follicular growth and maximum follicular diameter were unaffected by any of the three conditions. However, dominant follicle growth and maximum diameter were greater in the 60 animals that ovulated compared to the 14 that did not; 1.83+/-0.16 versus 0.96+/-0.26mm/day (P=0.014) and 19.4+/-0.4 versus 16.4+/-1.2mm (P=0.003), respectively. In conclusion, lameness reduced the proportion of cows that ovulated and the synergistic effect of high SCC and lameness reduced that proportion further. However, follicular growth and maximum follicular diameter were unaffected by high SCC, low BCS or lameness.


Assuntos
Doenças dos Bovinos/fisiopatologia , Coxeadura Animal/fisiopatologia , Leite/citologia , Folículo Ovariano/crescimento & desenvolvimento , Ovulação/fisiologia , Animais , Composição Corporal , Bovinos , Contagem de Células , Dinoprosta/administração & dosagem , Sincronização do Estro , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Folículo Ovariano/diagnóstico por imagem , Ultrassonografia
15.
Br J Cancer ; 99(9): 1426-32, 2008 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-18841158

RESUMO

In a placebo-controlled randomised study of the platelet-derived growth factor receptor (PDGFR) inhibitor imatinib mesylate and docetaxel in metastatic prostate cancer with bone metastases (n=116), no significant differences in progression-free and overall survival were observed. To evaluate pharmacodynamic correlates of outcomes, we assessed the association of plasma platelet-derived growth factor (PDGF) isoform kinetics and PDGFR inhibition with progression-free and overall survival by individual treatment arm. We found that in the docetaxel-placebo arm alone, the probability of decrease in PDGFR phosphorylation (Pr-Decr-pPDGFR) above 0.5 (vs 30 months (HR 3.1; P=0.04 in log-rank test). By contrast, in the docetaxel plus imatinib arm, the association of Pr-Decr-pPDGFR >0.5 with a rise in plasma PDGF isoform concentrations and inferior survival was not observed. The data suggest that dynamic changes in PDGFR phosphorylation in peripheral blood leukocytes predict docetaxel efficacy. Rising plasma PDGF concentrations may explain and/or mark docetaxel resistance. Validation and mechanistic studies addressing these unexpected findings should anticipate a confounding influence of concurrent PDGFR inhibitor therapy.


Assuntos
Antineoplásicos/uso terapêutico , Leucócitos/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Taxoides/uso terapêutico , Dimerização , Docetaxel , Humanos , Masculino , Análise Multivariada , Fosforilação , Fator de Crescimento Derivado de Plaquetas/análise , Fator de Crescimento Derivado de Plaquetas/química , Fator de Crescimento Derivado de Plaquetas/fisiologia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/mortalidade
16.
Int J Obes (Lond) ; 32(10): 1585-94, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18725894

RESUMO

OBJECTIVE: Nutrition during critical periods in early life may increase the subsequent risk of obesity, hypertension and metabolic diseases in adulthood. Few studies have focused on the long-term consequences of poor nutrition during the suckling period on the susceptibility to developing obesity when exposed to a palatable cafeteria-style high-fat diet (CD) after weaning. DESIGN: This study examined the impact of early undernutrition, followed by CD exposure, on blood pressure, hormones and genes important for insulin sensitivity and metabolism and skeletal muscle mRNA expression of adiponectin receptor 1 (AdipoR1), carnitine palmitoyl-transferase I (CPT-1), cytochrome c oxidase 4 (COX4) and peroxisome proliferator-activated receptor alpha (PPARalpha). Following normal gestation, Sprague-Dawley rat litters were adjusted to 18 (undernourished) or 12 (control) pups. Rats were weaned (day 21) onto either palatable CD or standard chow. RESULTS: Early undernourished rats were significantly lighter than control by 17 days, persisting into adulthood only when animals were fed chow after weaning. Regardless of litter size, rats fed CD had doubled fat mass at 15 weeks of age, and significant elevations in plasma leptin, insulin and adiponectin. Importantly, undernutrition confined to the suckling period, elevated circulating adiponectin regardless of post-weaning diet. Blood pressure was reduced in early undernourished rats fed chow, and increased by CD. Early undernutrition was associated with long-term elevations in the expression of AdipoR1, CPT-1, COX4 and PPARalpha in skeletal muscle. CONCLUSION: This study demonstrates the important role of early nutrition on body weight and metabolism, suggesting early undernourishment enhances insulin sensitivity and fatty-acid oxidation. The long-term potential benefit of limiting nutrition in the early postnatal period warrants further investigation.


Assuntos
Adiponectina/metabolismo , Dieta , Desnutrição/metabolismo , Músculo Esquelético/metabolismo , Receptores de Adiponectina/metabolismo , Análise de Variância , Animais , Pressão Sanguínea/fisiologia , Distribuição da Gordura Corporal , Carnitina O-Palmitoiltransferase/metabolismo , Ingestão de Energia/fisiologia , Leptina/metabolismo , Desnutrição/fisiopatologia , PPAR alfa/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Desmame
17.
Int J Obes (Lond) ; 32(2): 249-58, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17768423

RESUMO

OBJECTIVE: Palatable food disrupts normal appetite regulation, which may contribute to the etiology of obesity. Neuropeptide Y (NPY) and cholecystokinin play critical roles in the regulation of food intake and energy homeostasis, while adiponectin and carnitine palmitoyltransferase (CPT) are important for insulin sensitivity and fatty acid oxidation. This study examined the impact of short- and long-term consumption of palatable high-fat diet (HFD) on these critical metabolic regulators. METHODS: Male C57BL/6 mice were exposed to laboratory chow (12% fat), or cafeteria-style palatable HFD (32% fat) for 2 or 10 weeks. Body weight and food intake were monitored throughout. Plasma leptin, hypothalamic NPY and cholecystokinin, and mRNA expression of leptin, adiponectin, their receptors and CPT-1, in fat and muscles were measured. RESULTS: Caloric intake of the palatable HFD group was 2-3 times greater than control, resulting in a 37% higher body weight. Fat mass was already increased at 2 weeks; plasma leptin concentrations were 2.4 and 9 times higher than control at 2 and 10 weeks, respectively. Plasma adiponectin was increased at 10 weeks. Muscle adiponectin receptor 1 was increased at 2 weeks, while CPT-1 mRNA was markedly upregulated by HFD at both time points. Hypothalamic NPY and cholecystokinin content were significantly decreased at 10 weeks. CONCLUSION: Palatable HFD induced hyperphagia, fat accumulation, increased adiponectin, leptin and muscle fatty acid oxidation, and reduced hypothalamic NPY and cholecystokinin. Our data suggest that the adaptive changes in hypothalamic NPY and muscle fatty acid oxidation are insufficient to reverse the progress of obesity and metabolic consequences induced by a palatable HFD.


Assuntos
Colecistocinina/fisiologia , Gorduras na Dieta/farmacologia , Neuropeptídeo Y/fisiologia , Obesidade/etiologia , Receptores de Adiponectina/fisiologia , Adiponectina/metabolismo , Animais , Peso Corporal , Ingestão de Alimentos , Metabolismo Energético , Hiperfagia/complicações , Leptina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo
18.
J Dairy Sci ; 91(12): 4552-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19038930

RESUMO

The aim of the present study was to identify specific behavioral patterns that contribute to diminished estrus expression in lame cows. Behavioral scan and focal sampling were used to examine the effect of lameness on daily activity budgets, sexual behavior, feeding activities, and body condition score. A total of 59 milking cows (51.8 +/- 1.4 d postpartum) were monitored on a commercial dairy farm for 5 d following estrus synchronization. Overall, lame cows (n = 39) spent proportionately less time elevated on their feet and more time lying down compared with nonlame cows (n = 20). This included lame cows spending less time walking or standing. Overall, the total proportion of scans in which an estrous behavior was observed was very small but tended to be smaller for lame compared with nonlame cows. Throughout a day, lame cows displayed a lower proportion of estrous behaviors in the early morning. Lameness did not affect durations of drinking, grazing, or ruminating, or how these behavioral states fluctuated throughout the day. Similarly, rumination chewing rates were the same for lame and nonlame cows, and there was no association between lameness and dominance/displacement while feeding at a feed-fence. Lame cows did, however, have a slower bite rate at pasture and had a lower body condition score. Lame cows were also nearer the rear of the herd, both as they left the field and when entering the milking parlor. In conclusion, lame cows have longer lying times and spend less time standing, walking, and expressing an estrous behavior. Lame cows also have a lower bite rate at pasture and are more likely to be of lower body condition score.


Assuntos
Comportamento Animal/fisiologia , Estro/fisiologia , Atividade Motora/fisiologia , Comportamento Agonístico/fisiologia , Animais , Constituição Corporal/fisiologia , Bovinos , Doenças dos Bovinos/fisiopatologia , Indústria de Laticínios , Feminino , Coxeadura Animal/fisiopatologia , Mastigação/fisiologia , Comportamento Sexual Animal/fisiologia
19.
Biomark Res ; 6: 37, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30619609

RESUMO

BACKGROUND: Altered mitochondrial function and large-scale changes to DNA methylation patterns in the nuclear genome are both hallmarks of colorectal cancer (CRC). Mitochondria have multiple copies of a 16 kb circular genome that contains genes that are vital for their function. While DNA methylation is known to alter the nuclear genome in CRC, it is not clear whether it could have a similar influence in mtDNA; indeed, currently, the issue of whether mitochondrial genome (mtDNA) methylation occurs is controversial. Thus our goal here was to determine whether the methylation state of mtDNA is linked to mitochondrial gene transcription in colorectal adenomas, and to assess its suitability as a biomarker in CRC. METHODS: To investigate the relationship between DNA methylation and mitochondrial transcripts in adenomas, we performed RNA-sequencing and Whole Genome Bisulphite Sequencing (WGBS) of mtDNA-enriched DNA from normal mucosa and paired adenoma patient samples. RESULTS: Transcriptional profiling indicated that adenomas had reduced mitochondrial proton transport versus normal mucosa, consistent with altered mitochondrial function. The expression of 3 tRNAs that are transcribed from mtDNA were also decreased in adenoma. Overall methylation of CG dinucleotides in the nuclear genome was reduced in adenomas (68%) compared to normal mucosa (75%, P < 0.01). Methylation in mtDNA was low (1%) in both normal and adenoma tissue but we observed clusters of higher methylation at the ribosomal RNA genes. Levels of methylation within these regions did not differ between normal and adenoma tissue. CONCLUSIONS: We provide evidence that low-level methylation of specific sites does exist in the mitochondrial genome but that it is not associated with mitochondrial gene transcription changes in adenomas. Furthermore, as no large scale changes to mtDNA methylation were observed it is unlikely to be a suitable biomarker for early-stage CRC.

20.
Bone Joint J ; 100-B(1 Supple A): 31-35, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29292337

RESUMO

AIMS: To examine incidence of complications associated with outpatient total hip arthroplasty (THA), and to see if medical comorbidities are associated with complications or extended length of stay. PATIENTS AND METHODS: From June 2013 to December 2016, 1279 patients underwent 1472 outpatient THAs at our free-standing ambulatory surgery centre. Records were reviewed to determine frequency of pre-operative medical comorbidities and post-operative need for overnight stay and complications which arose. RESULTS: In 87 procedures, the patient stayed overnight for 23-hour observation, with 39 for convenience reasons and 48 (3.3%) for medical observation, most frequently urinary retention (13), obstructive sleep apnoea (nine), emesis (four), hypoxia (four), and pain management (six). Five patients (0.3%) experienced major complications within 48 hours, including three transferred to an acute facility; there was one death. Overall complication rate requiring unplanned care was 2.2% (32/1472). One or more major comorbidities were present in 647 patients (44%), including previous coronary artery disease (CAD; 50), valvular disease (nine), arrhythmia (219), thromboembolism history (28), obstructive sleep apnoea (171), chronic obstructive pulmonary disease (COPD; 124), asthma (118), frequent urination or benign prostatic hypertrophy (BPH; 217), or mild chronic renal insufficiency (11). CONCLUSION: The presence of these comorbidities was not associated with medical or surgical complications. However, presence of one or more major comorbidity was associated with an increased risk of overnight observation. Specific comorbidities associated with increased risk were CAD, COPD, and frequent urination/BPH. Outpatient THA is safe for a large proportion of patients without the need for a standardised risk assessment score. Risk of complications is not associated with presence of medical comorbidities. Cite this article: Bone Joint J 2018;100-B(1 Supple A):31-5.


Assuntos
Procedimentos Cirúrgicos Ambulatórios , Artroplastia de Quadril/métodos , Tempo de Internação , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Complicações Pós-Operatórias/epidemiologia , Fatores de Risco
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