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1.
Br Dent J ; 235(7): 447-448, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37828160
2.
Zootaxa ; 4619(3): zootaxa.4619.3.3, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31716289

RESUMO

This paper describes 15 cheilostome bryozoan species obtained from 15 sampling sites along the northern coast of the Persian Gulf in Iran. Two of the cheilostomes are described as new species: Parasmittina cryptoavicularia n. sp. and Trematooecia persica n. sp. The majority of species found in this study (67%) have a tropical to subtropical Indo-Pacific distribution, while the remainder are more widely distributed. Several are fouling species known from warmer seas around the globe. Further sampling efforts are needed to obtain a better estimate of the true bryozoan diversity in the region which is almost certainly much greater than the 15 species described in this study.


Assuntos
Briozoários , Animais , Oceano Índico , Irã (Geográfico)
3.
J Physiol ; 596(23): 5709-5722, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29533463

RESUMO

Caesarean section and instrumental delivery rates are increasing in many parts of the world for a range of cultural and medical reasons, with limited consideration as to how 'mode of delivery' may impact on childhood and long-term health. However, babies born particularly by pre-labour caesarean section appear to have a subtly different physiology from those born by normal vaginal delivery, with both acute and chronic complications such as respiratory and cardio-metabolic morbidities being apparent. It has been hypothesized that inherent mechanisms within the process of labour and vaginal delivery, far from being a passive mechanical process by which the fetus and placenta are expelled from the birth canal, may trigger certain protective developmental processes permissive for normal immunological and physiological development of the fetus postnatally. Traditionally the primary candidate mechanism has been the hormonal surges or stress response associated with labour and vaginal delivery, but there is increasing awareness that transfer of the maternal microbiome to the infant during parturition. Transgenerational transmission of disease traits through epigenetics are also likely to be important. Interventions such as probiotics, neonatal gut seeding and different approaches to clinical care have potential to influence parturition physiology and improve outcomes for infants.


Assuntos
Saúde do Lactente , Trabalho de Parto , Parto , Animais , Feminino , Microbioma Gastrointestinal , Humanos , Recém-Nascido , Gravidez
5.
Int J Obes (Lond) ; 39(9): 1339-48, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25971926

RESUMO

BACKGROUND: Maternal obesity increases offspring propensity to metabolic dysfunctions and to non-alcoholic fatty liver disease (NAFLD), which may lead to cirrhosis or liver cancer. The circadian clock is a transcriptional/epigenetic molecular machinery synchronising physiological processes to coordinate energy utilisation within a 24-h light/dark period. Alterations in rhythmicity have profound effects on metabolic pathways, which we sought to investigate in offspring with programmed NAFLD. METHODS: Mice were fed a standard or an obesogenic diet (OD), before and throughout pregnancy, and during lactation. Offspring were weaned onto standard or an OD at 3 weeks postpartum and housed in 12:12 light/dark conditions. Biochemical and histological indicators of NAFLD and fibrosis, analysis of canonical clock genes with methylation status and locomotor activity were investigated at 6 months. RESULTS: We show that maternal obesity interacts with an obesogenic post-weaning diet to promote the development of NAFLD with disruption of canonical metabolic rhythmicity gene expression in the liver. We demonstrate hypermethylation of BMAL-1 (brain and muscle Arnt like-1) and Per2 promoter regions and altered 24-h rhythmicity of hepatic pro-inflammatory and fibrogenic mediators. CONCLUSIONS: These data implicate disordered circadian rhythms in NAFLD and suggest that disruption of this system during critical developmental periods may be responsible for the onset of chronic liver disease in adulthood.


Assuntos
Fatores de Transcrição ARNTL/metabolismo , Ritmo Circadiano , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Animais , Animais Recém-Nascidos , Metilação de DNA , Modelos Animais de Doenças , Feminino , Lactação , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/patologia , Proteínas Circadianas Period/metabolismo , Gravidez
6.
Acta Physiol (Oxf) ; 210(3): 508-23, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24433239

RESUMO

Mother-child cohort studies have established that both pre-pregnancy body mass index (BMI) and gestational weight gain are independently associated with cardio-metabolic risk factors in young adult offspring, including systolic and diastolic blood pressure. Animal models in sheep and non-human primates provide further evidence for the influence of maternal obesity on offspring cardiovascular function, whilst recent studies in rodents suggest that perinatal exposure to the metabolic milieu of maternal obesity may permanently change the central regulatory pathways involved in blood pressure regulation. Leptin plays an important role in the central control of appetite, is also involved in activation of efferent sympathetic pathways to both thermogenic and non-thermogenic tissues, such as the kidney, and is therefore implicated in obesity-related hypertension. Leptin is also thought to have a neurotrophic role in the development of the hypothalamus, and altered neonatal leptin profiles secondary to maternal obesity are associated with permanently altered hypothalamic structure and function. In rodent studies, maternal obesity confers persistent sympathoexcitatory hyper-responsiveness and hypertension acquired in the early stages of development. Experimental neonatal hyperleptinaemia in naive rat pups provides further evidence of heightened sympathetic tone and proof of principle that hyperleptinaemia during a critical window of hypothalamic development may directly lead to adulthood hypertension. Insight from these animal models raises the possibility that early-life exposure to leptin in humans may lead to early onset essential hypertension. Ongoing mother-child cohort and intervention studies in obese pregnant women provide a unique opportunity to address associations between maternal obesity and offspring cardiovascular function. The goal of the review is to highlight the potential importance of leptin in the developmental programming of hypertension in obese pregnancy.


Assuntos
Hipertensão/congênito , Hipertensão/metabolismo , Leptina/metabolismo , Obesidade/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Animais , Feminino , Humanos , Mães , Obesidade/complicações , Obesidade/fisiopatologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia
8.
Mol Phylogenet Evol ; 62(2): 718-35, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22126903

RESUMO

We present the most comprehensive molecular phylogeny of bryozoans to date. Our concatenated alignment of two nuclear ribosomal and five mitochondrial genes includes 95 taxa and 13,292 nucleotide sites, of which 8297 were included. The number of new sequences generated during this project are for each gene:ssrDNA (32), lsrDNA (22), rrnL (38), rrnS (35), cox1 (37), cox3 (34), and cytb (44). Our multi-gene analysis provides a largely stable topology across the phylum. The major groups were unambiguously resolved as (Phylactolaemata (Cyclostomata (Ctenostomata, Cheilostomata))), with Ctenostomata paraphyletic. Within Phylactolaemata, (Stephanellidae, Lophopodidae) form the earliest divergent clade. Fredericellidae is not resolved as a monophyletic family and forms a clade together with Plumatellidae, Cristatellidae and Pectinatellidae, with the latter two as sister taxa. Hyalinella and Gelatinella nest within the genus Plumatella. Cyclostome taxa fall into three major clades: i. (Favosipora (Plagioecia, Rectangulata)); ii. (Entalophoroecia ((Diplosolen, Cardioecia) (Frondipora, Cancellata))); and iii. (Articulata ((Annectocyma, Heteroporidae) (Tubulipora (Tennysonia, Idmidronea)))), with suborders Tubuliporina and Cerioporina, and family Plagioeciidae each being polyphyletic. Ctenostomata is composed of three paraphyletic clades to the inclusion of Cheilostomata: ((Alcyonidium, Flustrellidra) (Paludicella (Anguinella, Triticella)) (Hislopia (Bowerbankia, Amathia)) Cheilostomata); Flustrellidra nests within the genus Alcyonidium, and Amathia nests within the genus Bowerbankia. Suborders Carnosa and Stolonifera are not monophyletic. Within the cheilostomes, Malacostega is paraphyletic to the inclusion of all other cheilostomes. Conopeum is the most early divergent cheilostome, forming the sister group to ((Malacostega, Scrupariina, Inovicellina) ((Hippothoomorpha, Flustrina) (Lepraliomorpha, Umbonulomorpha))); Flustrina is paraphyletic to the inclusion of the hippothoomorphs; neither Lepraliomorpha nor Umbonulomorpha is monophyletic. Ascophorans are polyphyletic, with hippothoomorphs grouping separately from lepraliomorphs and umbonulomorphs; no cribrimorphs were included in the analysis. Results are discussed in the light of molecular and morphological evidence. Ancestral state reconstruction of larval strategy in Gymnolaemata revealed planktotrophy and lecithotrophy as equally parsimonious solutions for the ancestral condition. More comprehensive taxon sampling is expected to clarify this result. We discuss the extent of non-bryozoan contaminant sequences deposited in GenBank and their impact on the reconstruction of metazoan phylogenies and those of bryozoan interrelationships.


Assuntos
Briozoários/genética , Evolução Molecular , Genes Mitocondriais , Especiação Genética , Filogenia , Algoritmos , Animais , Sequência de Bases , Teorema de Bayes , Briozoários/classificação , Primers do DNA , Bases de Dados Genéticas , Larva/classificação , Larva/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie
9.
Horm Metab Res ; 42(13): 923-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20972941

RESUMO

Offspring of rats fed high-fat diets during pregnancy and lactation develop glucose intolerance and islet dysfunction in adulthood. Because other models of developmental programming of glucose intolerance are associated with defective islet development, we investigated whether high-fat exposure during fetal or neonatal life impairs islet development and function, thereby contributing to islet dysfunction in later life. Female rats were fed control or high-fat diets and their pups cross-fostered after birth to represent 4 groups with each combination of control and high-fat diet for the natural and foster mother. In a time course study, pups were kept with the natural mother until weaning. Pancreases were analysed for insulin content, beta cell mass, and islet number. Isolated islets were studied for insulin secretory responses and susceptibility to palmitate-induced apoptosis assessed by caspases 3/9 activity. Pancreatic insulin content and beta cell mass were increased in pups exposed to maternal high-fat diets after birth, whereas glucose-stimulated insulin secretion from islets of high-fat offspring at 5 and 11 days of age was lower than controls. Islets from control rats of 2-14 days of age were resistant to the pro-apoptotic effects of palmitate seen in older animals. The immature beta cell is therefore insensitive to toxic effects of palmitate and may compensate for the inhibitory effects on insulin secretion by increasing beta cell mass. The data suggest that susceptibility to glucose intolerance in offspring of dams fed high-fat diets may not be a consequence of deleterious effects on beta cell mass in early life.


Assuntos
Dieta , Gorduras na Dieta/toxicidade , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/fisiologia , Efeitos Tardios da Exposição Pré-Natal/patologia , Animais , Animais Recém-Nascidos , Animais Lactentes , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 9/metabolismo , Citocinas/farmacologia , Ácidos Graxos/toxicidade , Feminino , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/anatomia & histologia , Ilhotas Pancreáticas/enzimologia , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
10.
Mol Hum Reprod ; 13(10): 729-36, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17804434

RESUMO

This study determined the effects of inhibiting vascular endothelial growth factor (VEGF) at follicle selection. Marmosets were given an injection of VEGF antagonist, the VEGF Trap on Day 5 of the follicular phase and ovaries were evaluated on Day 10 or 15. Ovaries from controls were assessed on Day 5 (time of selection), Day 10 (peri-ovulatory) and Day 15 (luteal phase). At Day 10, ovaries of four of the five controls contained dominant follicles, while one had ovulated. VEGF Trap-treated ovaries also contained large follicles on Day 10, but VEGF inhibition had suppressed endothelial cell proliferation, leading to reductions in the thecal vascularization and plasma estradiol relative to controls. By Day 15, ovaries of controls contained active corpora lutea whereas ovaries of four of the five treated animals still contained large antral follicles similar in size to pre-ovulatory follicles, and one had small, avascular corpora lutea. However, these follicles had a restricted vasculature, increased incidence of activated caspase-3 staining and morphological features indicating they would become degenerative non-functional cysts. These results show that after follicle selection, VEGF is essential for angiogenesis and the generation of healthy ovulatory follicles and corpora lutea, but fluid accumulation can still occur in selected follicles in the absence of VEGF.


Assuntos
Atresia Folicular/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Ovário/efeitos dos fármacos , Proteínas Recombinantes de Fusão/farmacologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Callithrix , Proliferação de Células/efeitos dos fármacos , Corpo Lúteo/efeitos dos fármacos , Corpo Lúteo/metabolismo , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Estradiol/sangue , Feminino , Atresia Folicular/metabolismo , Fase Folicular , Fragmentos Fc das Imunoglobulinas/genética , Fase Luteal , Folículo Ovariano/irrigação sanguínea , Folículo Ovariano/citologia , Ovário/citologia , Ovário/metabolismo , Progesterona/sangue , Receptores de Fatores de Crescimento do Endotélio Vascular/sangue , Receptores de Fatores de Crescimento do Endotélio Vascular/genética , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Proteínas Recombinantes de Fusão/sangue , Proteínas Recombinantes de Fusão/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
J Evol Biol ; 20(1): 301-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17210023

RESUMO

Two standard mathematical formulations of kin-selection models can be found. Inclusive fitness is an actor-centred approach, which calculates the fitness effect on a number of recipients of the behaviour of a single actor. Direct fitness is a recipient-centred approach, which calculates the fitness effect on the recipient of the behaviour of a number of actors. Inclusive fitness offers us a powerful heuristic, of choosing behaviour to maximize fitness, but direct fitness can be mathematically easier to work with and has recently emerged as the preferred approach of theoreticians. In this paper, we explore the fundamental connection between these two approaches in both homogeneous and class-structured populations, and we show that under simple assumptions (mainly fair meiosis and weak selection) they provide equivalent formulations, which correspond to the predictions of Price's equation for allele frequency change. We use a couple of examples to highlight differences in their conception and formulation, and we briefly discuss a two-species example in which we have a class of 'actor' that is never a 'recipient', which the standard direct fitness method can handle but the usual inclusive fitness cannot.


Assuntos
Evolução Biológica , Genética Populacional , Modelos Teóricos , Seleção Genética , Simulação por Computador , Comportamento Cooperativo , Reprodução/genética , Especificidade da Espécie
12.
Exp Physiol ; 92(2): 287-98, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17170060

RESUMO

Converging lines of evidence from epidemiological studies and animal models now indicate that the origins of obesity and related metabolic disorders lie not only in the interaction between genes and traditional adult risk factors, such as unbalanced diet and physical inactivity, but also in the interplay between genes and the embryonic, fetal and early postnatal environment. Whilst studies in man initially focused on the relationship between low birth weight and risk of adult obesity and metabolic syndrome, evidence is also growing to suggest that increased birth weight and/or adiposity at birth can also lead to increased risk for childhood and adult obesity. Hence, there appears to be increased risk of obesity at both ends of the birth weight spectrum. Animal models, including both under- and overnutrition in pregnancy and lactation lend increasing support to the developmental origins of obesity. This review focuses upon the influence of the maternal nutritional and hormonal environment in pregnancy in permanently programming appetite and energy expenditure and the hormonal, neuronal and autocrine mechanisms that contribute to the maintenance of energy balance in the offspring. We discuss the potential maternal programming 'vectors' and the molecular mechanisms that may lead to persistent pathophysiological changes resulting in subsequent disease. The perinatal environment, which appears to programme subsequent obesity, provides a potential therapeutic target, and work in this field will readily translate into improved interventional strategies to stem the growing epidemic of obesity, a disease which, once manifest, has proven particularly resistant to treatment.


Assuntos
Desenvolvimento Embrionário , Desenvolvimento Fetal , Fenômenos Fisiológicos da Nutrição Materna , Obesidade/embriologia , Obesidade/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal , Adiposidade , Adulto , Animais , Regulação do Apetite , Peso ao Nascer , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Modelos Animais de Doenças , Desenvolvimento Embrionário/genética , Metabolismo Energético , Feminino , Desenvolvimento Fetal/genética , Predisposição Genética para Doença , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Obesidade/epidemiologia , Obesidade/genética , Obesidade/metabolismo , Gravidez , Fatores de Risco
14.
J Physiol ; 571(Pt 2): 477-87, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16410278

RESUMO

Dietary soy intake in man is proposed to provide cardiovascular protection, but it is not established whether this property is attributable to the soy protein per se or to associated dietary isoflavones. This investigation aimed to establish whether the dietary isoflavones in soy protein affect cardiovascular function. Ten days prior to mating, male and female Wistar rats were habituated to either a soy based isoflavone rich diet (plasma concentration 1.87 micromol l(-1) isoflavones) or the same diet after isoflavone elution (plasma isoflavone not detectable). Offspring were weaned onto and maintained on the same diet as their dam and sire for 6 months. Blood pressure, and constrictor and dilator responses in the aorta and mesenteric resistance arteries were assessed at 3 and 6 months of age. There was no effect of isoflavone removal from the diet on blood pressure, heart rate, aortic function or mesenteric artery contractile function, at either 3 or 6 months of age. Resistance mesenteric arteries from 6-month-old female rats fed the isoflavone rich diet demonstrated a modest increase in arterial distensibility compared with those fed the depleted diet, and mesenteric arteries from male and female rats fed the isoflavone rich diet showed increased sensitivity to acetylcholine. In summary, the isoflavone content of soy protein has no influence on blood pressure in healthy rats fed a diet based on soy protein, but influences small artery function.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Sistema Cardiovascular , Dieta , Isoflavonas/farmacologia , Proteínas de Soja/farmacologia , Animais , Aorta/fisiologia , Proteínas Alimentares/farmacologia , Ciclo Estral/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Isoflavonas/administração & dosagem , Isoflavonas/sangue , Lipídeos/sangue , Masculino , Artérias Mesentéricas/fisiologia , Ratos , Ratos Wistar , Proteínas de Soja/administração & dosagem , Fatores de Tempo
15.
Am J Physiol Regul Integr Comp Physiol ; 288(1): R127-33, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15308487

RESUMO

Epidemiological and animal studies suggest that diet-induced epigenetic modifications in early life can contribute to development of the metabolic syndrome in adulthood. We previously reported features of the metabolic syndrome in adult offspring of rats fed a diet rich in animal fat during pregnancy and suckling. We now report a study to compare the relative effects of high-fat feeding during 1) pregnancy and 2) the suckling period in the development of these disorders. As observed previously, 6-mo-old female offspring of fat-fed dams suckled by the same fat-fed dams (OHF) demonstrated raised blood pressure, despite being fed a balanced diet from weaning. Female offspring of fat-fed dams "cross fostered" to dams consuming a control diet during suckling (OHF/C) demonstrated raised blood pressure compared with controls (OC) [systolic blood pressure (SBP; mmHg) means +/- SE: OHF/C, 132.5 +/- 3.0, n = 6 vs. OC, 119.0 +/- 3.8, n = 7, P < 0.05]. Female offspring of controls cross fostered to dams consuming the fat diet (OC/HF) were also hypertensive [SBP (mmHg) 131.0 +/- 2.5 mmHg, n = 6 vs. OC, P < 0.05]. Endothelium-dependent relaxation (EDR) of male and female OHF and OHF/C mesenteric small arteries was similar and blunted compared with OC (P < 0.001). OC/HF arteries showed profoundly impaired EDR (OC/HF vs. OHF, P < 0.001). OHF/C and OC/HF demonstrated hyperinsulinemia and increased adiposity. Features of the metabolic syndrome in adult offspring of fat-fed rats can be acquired both antenatally and during suckling. However, exposure during pregnancy confers adaptive protection against endothelial dysfunction induced by maternal fat feeding during suckling.


Assuntos
Gorduras na Dieta/farmacologia , Hemodinâmica/fisiologia , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Efeitos Tardios da Exposição Pré-Natal , Animais , Peso Corporal , Comportamento Alimentar/fisiologia , Feminino , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Lactação , Artérias Mesentéricas/fisiopatologia , Síndrome Metabólica/embriologia , Gravidez , Fenômenos Fisiológicos da Nutrição Pré-Natal/fisiologia , Ratos , Ratos Sprague-Dawley , Vasodilatação/efeitos dos fármacos
16.
J Endocrinol ; 183(1): 1-17, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15525569

RESUMO

Angiogenesis is required for normal follicular development but the role of gonadotrophins in the control of follicular angiogenesis remains to be elucidated. This study investigated the effects of treatment with GnRH antagonist in vivo on follicular development and angiogenesis in the marmoset. GnRH antagonist was administered on either follicular day 0 or day 5 of the 10-day follicular phase with ovaries collected on day 10. Ovaries from control marmosets were studied at day 5 (mid follicular phase) and day 10 (periovulatory period). Ovaries were fixed, serial sectioned and subjected to morphological analysis and immunocytochemistry to determine cell proliferation and follicular endothelial cell area and in situ hybridization to assess changes in expression of vascular endothelial growth factor (VEGF). Treatment with GnRH antagonist from day 0-10 resulted in an absence of dominant preovulatory follicles seen in controls. In the remaining tertiary follicles granulosa, theca and endothelial cell proliferation was reduced, resulting in a minor reduction in vascular density. However, VEGF mRNA expression was unaffected by treatment. Treatment from day 5-10 did not prevent development of ovulatory size follicles, but they were atretic and lacked VEGF mRNA. These results suggest that while VEGF expression in the preovulatory follicle is under gonadotrophic control it is not dependent on normal gonadotrophin secretion in tertiary follicles, indicating that there are other paracrine factors regulating VEGF expression in the developing ovarian follicle.


Assuntos
Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Antagonistas de Hormônios/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Oligopeptídeos/farmacologia , Folículo Ovariano/fisiologia , Animais , Callithrix , Proliferação de Células , Tamanho Celular , Células Endoteliais/citologia , Feminino , Fase Folicular , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Ovário/irrigação sanguínea , Ovário/citologia , RNA Mensageiro/análise , Fator A de Crescimento do Endotélio Vascular/genética
17.
J Physiol ; 558(Pt 3): 943-51, 2004 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15194731

RESUMO

We recently reported vascular dysfunction in adult offspring of rats fed a fat-rich (animal lard) diet in pregnancy. This study reports further characterization of constrictor and dilator function in mesenteric and caudal femoral arteries from 180-day-old offspring of dams fed the high fat diet (OHF). Endothelium-dependent relaxation in response to acetylcholine (10(-9)-10(-5)m) was impaired in mesenteric small arteries from male and female OHF compared with offspring of dams fed normal chow (males (maximum percentage relaxation): OHF 67.92 +/- 2.89, n= 8 versus control 92.08 +/- 2.19, n= 8, P < 0.01). Substantial relaxation in response to acetycholine in control mesenteric arteries remained after inhibition of nitric oxide synthase, soluble guanylate cyclase and cyclo-oxygenase but was blocked by 25 mm potassium. This component of relaxation, attributed to EDHF, was significantly reduced in OHF mesenteric arteries compared with controls. However, EDHF played a minor role in acetylcholine-induced relaxation in both control and OHF femoral caudal arteries (male and female). In these arteries, in contrast to mesenteric vessels, acetylcholine-induced relaxation was significantly enhanced in OHF but only in males (ACh (maximum percentage relaxation): OHF 58.40 +/- 4.39, n= 8 versus male controls 32.18 +/- 6.36, P < 0.05). This was attributable to enhanced nitric oxide-mediated relaxation. In conclusion, reduced endothelium-dependent relaxation in OHF mesenteric arteries is due to impaired EDHF-mediated relaxation. This defect was not apparent in femoral arteries in which EDHF has a less prominent role.


Assuntos
Fatores Biológicos/fisiologia , Gorduras na Dieta/farmacologia , Efeitos Tardios da Exposição Pré-Natal , Vasodilatação/fisiologia , Acetilcolina/farmacologia , Animais , Fatores Biológicos/antagonistas & inibidores , Relação Dose-Resposta a Droga , Feminino , Técnicas In Vitro , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley , Vasodilatação/efeitos dos fármacos
18.
Exp Physiol ; 88(3): 389-98, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12719763

RESUMO

We hypothesised that maternal uterine artery vascular dysfunction could contribute to cardiovascular dysfunction in offspring of rats fed a diet rich in fat. Sprague-Dawley rats were fed for 10 days prior to pregnancy and throughout gestation either: (a) a control breeding diet, or (b) the same diet supplemented with 20 % w/w lard, vitamins, essential micronutrients and protein to control values. At 20 days gestation vascular function was assessed in uterine arteries and third-order mesenteric arteries. Vascular reactivity in response to application of potassium, noradrenaline, the thromboxane analogue U46619, acetylcholine and nitric oxide was assessed. Maternal plasma concentrations of factors likely to contribute to endothelial dysfunction were measured. Maximum acetylcholine-induced relaxation was impaired in the mesenteric arteries of the lard-fed dams (max % relaxation: lard-fed, 69.7 +/- 6.48; control, 85.37 +/- 2.69, P = 0.03). Uterine artery vascular function was similar in the two groups (max % acetylcholine-induced relaxation: lard-fed, 73.7 +/- 4.01; control, 77.5 +/- 4.72, P = 0.98). Concentrations of plasma lipids, 8-epi-PGF(2alpha) and leptin were normal, whereas insulin and corticosterone concentrations were raised in the lard-fed group (insulin (ng ml(-1)): lard-fed, 8.04 +/- 0.47; control, 1.35 +/- 0.37, P < 0.0001; corticosterone (ng ml(-1)): lard-fed, 1164.0 +/- 170.9; control, 541.9 +/- 96.3, P = 0.005). Fetal and placental weights were reduced in lard-fed dams (fetus (g): lard-fed, 4.27 +/- 0.38; control, 2.96 +/- 0.40, P = 0.025; placenta (g): lard-fed, 0.72 +/- 0.06; control, 0.57 +/- 0.04, P = 0.05). Cardiovascular dysfunction in offspring is not associated with reduced uterine artery endothelial function but is associated with activation of the hypothalamic-pituitary-adrenal axis, hyperinsulinaemia and fetoplacental growth retardation.


Assuntos
Gorduras na Dieta/farmacologia , Dinoprosta/análogos & derivados , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Útero/irrigação sanguínea , Ração Animal , Animais , Artérias/fisiologia , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Corticosterona/sangue , Dieta , Ingestão de Alimentos/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , F2-Isoprostanos/sangue , Feminino , Insulina/sangue , Leptina/sangue , Peroxidação de Lipídeos/efeitos dos fármacos , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , Artérias Mesentéricas/fisiologia , Gravidez , Ratos , Ratos Sprague-Dawley , Reprodução/efeitos dos fármacos , Vasoconstrição/fisiologia , Vasodilatação/fisiologia
19.
Anal Bioanal Chem ; 374(6): 1147-54, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12458434

RESUMO

In IMEP-8, two samples of high purity CO(2)(g), with different carbon and oxygen isotope ratios were distributed to 27 participants, originating from 14 countries and from various isotopic measurement domains (geochemistry, atmospheric and food chemistry), but particularly set up for food laboratories. In total 19 laboratories reported results. The outcome of this comparison exercise shows that the laboratories reported carbon and oxygen isotope results in good agreement with the reference values across the domains. The reported results for delta(13)C(VPDB) (carbon) for both materials are within 1 per thousand. However, for the reported results of delta(18)O(VPDB) (oxygen) for both materials the overall spread of the reported results is about 11 per thousand. Within this spread two distinct groups of participants can be identified, where the results within each group vary about 2 per thousand. The latter seems to be caused by calculation errors by participants of the reporting delta(18)O(VPDB) values. As requested, participants also reported the isotope amount ratio for carbon and oxygen in the CO(2) samples. For carbon, all reported results for both materials agree with the isotope ratio value, which can be traced back to the value reported by Craig. For oxygen, all results are in good agreement and deviate by a maximum of 0.5% from the reference values measured at IRMM. Work carried out indicates the carbon isotope ratio, for both samples IMEP-8A and IMEP-8B, differ from those reported by Craig by as much as 1.2%. In the case of oxygen, this deviation is far smaller. Both data sets, i.e. the one realised by Craig and the one realised at IRMM, demonstrate traceability to SI. It is clear that both values significantly disagree.

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