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1.
J Anim Sci ; 93(6): 2693-705, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26115257

RESUMO

One of the main animal health problems in tropical and subtropical cattle production is the bovine tick, which causes decreased performance, hide devaluation, increased production costs with acaricide treatments, and transmission of infectious diseases. This study investigated the utility of genomic prediction as a tool to select Braford (BO) and Hereford (HH) cattle resistant to ticks. The accuracy and bias of different methods for direct and blended genomic prediction was assessed using 10,673 tick counts obtained from 3,435 BO and 928 HH cattle belonging to the Delta G Connection breeding program. A subset of 2,803 BO and 652 HH samples were genotyped and 41,045 markers remained after quality control. Log transformed records were adjusted by a pedigree repeatability model to estimate variance components, genetic parameters, and breeding values (EBV) and subsequently used to obtain deregressed EBV. Estimated heritability and repeatability for tick counts were 0.19 ± 0.03 and 0.29 ± 0.01, respectively. Data were split into 5 subsets using k-means and random clustering for cross-validation of genomic predictions. Depending on the method, direct genomic value (DGV) prediction accuracies ranged from 0.35 with Bayes least absolute shrinkage and selection operator (LASSO) to 0.39 with BayesB for k-means clustering and between 0.42 with BayesLASSO and 0.45 with BayesC for random clustering. All genomic methods were superior to pedigree BLUP (PBLUP) accuracies of 0.26 for k-means and 0.29 for random groups, with highest accuracy gains obtained with BayesB (39%) for k-means and BayesC (55%) for random groups. Blending of historical phenotypic and pedigree information by different methods further increased DGV accuracies by values between 0.03 and 0.05 for direct prediction methods. However, highest accuracy was observed with single-step genomic BLUP with values of 0.48 for -means and 0.56, which represent, respectively, 84 and 93% improvement over PBLUP. Observed random clustering cross-validation breed-specific accuracies ranged between 0.29 and 0.36 for HH and between 0.55 and 0.61 for BO, depending on the blending method. These moderately high values for BO demonstrate that genomic predictions could be used as a practical tool to improve genetic resistance to ticks and in the development of resistant lines of this breed. For HH, accuracies are still in the low to moderate side and this breed training population needs to be increased before genomic selection could be reliably applied to improve tick resistance.


Assuntos
Doenças dos Bovinos/parasitologia , Predisposição Genética para Doença , Genômica/métodos , Modelos Genéticos , Infestações por Carrapato/veterinária , Animais , Teorema de Bayes , Cruzamento , Bovinos , Doenças dos Bovinos/genética , Genoma , Genótipo , Característica Quantitativa Herdável , Infestações por Carrapato/genética
2.
Anim Genet ; 45(6): 771-81, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25183526

RESUMO

Brazilian Nellore cattle (Bos indicus) have been selected for growth traits for over more than four decades. In recent years, reproductive and meat quality traits have become more important because of increasing consumption, exports and consumer demand. The identification of genome regions altered by artificial selection can potentially permit a better understanding of the biology of specific phenotypes that are useful for the development of tools designed to increase selection efficiency. Therefore, the aims of this study were to detect evidence of recent selection signatures in Nellore cattle using extended haplotype homozygosity methodology and BovineHD marker genotypes (>777,000 single nucleotide polymorphisms) as well as to identify corresponding genes underlying these signals. Thirty-one significant regions (P < 0.0001) of possible recent selection signatures were detected, and 19 of these overlapped quantitative trait loci related to reproductive traits, growth, feed efficiency, meat quality, fatty acid profiles and immunity. In addition, 545 genes were identified in regions harboring selection signatures. Within this group, 58 genes were associated with growth, muscle and adipose tissue metabolism, reproductive traits or the immune system. Using relative extended haplotype homozygosity to analyze high-density single nucleotide polymorphism marker data allowed for the identification of regions potentially under artificial selection pressure in the Nellore genome, which might be used to better understand autozygosity and the effects of selection on the Nellore genome.


Assuntos
Bovinos/genética , Marcadores Genéticos , Carne , Seleção Genética , Animais , Brasil , Cruzamento , Bovinos/classificação , Estudos de Associação Genética , Genótipo , Haplótipos , Masculino , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
3.
Physiol Genomics ; 45(21): 1012-20, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24022219

RESUMO

Meat quality traits are economically important because they affect consumers' acceptance, which, in turn, influences the demand for beef. However, selection to improve meat quality is limited by the small numbers of animals on which meat tenderness can be evaluated due to the cost of performing shear force analysis and the resultant damage to the carcass. Genome wide-association studies for Warner-Bratzler shear force measured at different times of meat aging, backfat thickness, ribeye muscle area, scanning parameters [lightness, redness (a*), and yellowness] to ascertain color characteristics of meat and fat, water-holding capacity, cooking loss (CL), and muscle pH were conducted using genotype data from the Illumina BovineHD BeadChip array to identify quantitative trait loci (QTL) in all phenotyped Nelore cattle. Phenotype count for these animals ranged from 430 to 536 across traits. Meat quality traits in Nelore are controlled by numerous QTL of small effect, except for a small number of large-effect QTL identified for a*fat, CL, and pH. Genomic regions harboring these QTL and the pathways in which the genes from these regions act appear to differ from those identified in taurine cattle for meat quality traits. These results will guide future QTL mapping studies and the development of models for the prediction of genetic merit to implement genomic selection for meat quality in Nelore cattle.


Assuntos
Bovinos/genética , Genoma , Carne/normas , Locos de Características Quantitativas/genética , Tecido Adiposo/metabolismo , Algoritmos , Animais , Teorema de Bayes , Mapeamento Cromossômico , Cromossomos de Mamíferos/genética , Estudos de Associação Genética , Genótipo , Concentração de Íons de Hidrogênio , Carne/análise , Fenótipo , Polimorfismo de Nucleotídeo Único , Fatores de Tempo
4.
J Endocrinol ; 217(3): 303-15, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23482704

RESUMO

Metabolic alterations in obese and overweight mothers impact the placenta and the fetus, leading to anomalies in fetal growth and lipid accretion. The primary aim of the study was to examine the effect of a saturated fat-rich diet (FD) on growth, lipid accretion, and lipases, leptin and leptin receptor (ObR) expression in the placenta and fetal liver. We also aimed to find a role for fetal leptin in the modulation of placental and fetal liver lipase and ObR expression. Six-week-old rats were fed with a standard rat chow (control) or a 25% FD for 7 weeks until mating and during pregnancy. Also, in a group of control rats, fetuses were injected with leptin on days 19, 20, and 21 of pregnancy. On day 21, we assessed lipidemia, insulinemia, and leptinemia in mothers and fetuses. In the placenta and fetal liver, lipid concentration was assessed by thin layer chromatography (TLC) and the gene expression of lipoprotein lipase (LPL), endothelial lipase, insulin receptor (Insr), leptin, and ObR by RT-PCR. The FD induced hypertriglyceridemia and hyperleptinemia (P<0.01) in mothers and fetuses, an increase in maternal (P<0.05) and fetal weight (P<0.01), overaccumulation of lipids in fetal liver (P<0.01), and enhanced leptin expression in the placenta and fetal liver (P<0.05). Placental expression of IR and LPL was increased (P<0.05), and ObR decreased (P<0.05) in the FD group. Fetal administration of leptin induced the placental and fetal liver downregulation of ObR (P<0.05) and upregulation of LPL expression (P<0.05). The FD led to increased fetal lipid levels, which may result from high maternal lipid availability and fetal leptin effects.


Assuntos
Dieta Hiperlipídica , Ácidos Graxos/farmacologia , Lipídeos/sangue , Lipase Lipoproteica/metabolismo , Placenta/metabolismo , Receptores para Leptina/metabolismo , Animais , Gorduras na Dieta/metabolismo , Gorduras na Dieta/farmacologia , Feminino , Leptina/genética , Leptina/metabolismo , Lipase/genética , Lipase/metabolismo , Lipase Lipoproteica/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Placenta/efeitos dos fármacos , Gravidez , Ratos , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Receptores para Leptina/genética
5.
Curr Med Chem ; 20(18): 2338-50, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23521676

RESUMO

Lipids are crucial structural and bioactive components that sustain embryo, fetal and placental development and growth. Intrauterine development can be disturbed by several diseases that impair maternal lipid homeostasis and lead to abnormal lipid concentrations in the fetal circulation. Deficiency in essential fatty acids can lead to congenital malformations and visual and cognitive problems in the newborn. Either deficient mother-to-fetus lipid transfer or abnormal maternal- fetal lipid metabolism can cause fetal growth restriction. On the other hand, excessive mother-to-fetus fatty acid transfer can induce fetal overgrowth and lipid overacummulation in different fetal organs and tissues. The placenta plays a fundamental role in the transfer of lipid moieties to the fetal compartment and is affected by maternal diseases associated with impaired lipid homeostasis. Postnatal consequences may be evident in the neonatal period or later in life. Indeed, both defects and excess of different lipid species can lead to the intrauterine programming of metabolic and cardiovascular diseases in the offspring. This review summarizes the lipid impairments induced by different pathologies, including placental insufficiency, malnutrition, obesity and diabetes, and their consequent developmental defects.


Assuntos
Anormalidades Congênitas/etiologia , Metabolismo dos Lipídeos , Complicações na Gravidez/metabolismo , Animais , Anormalidades Congênitas/metabolismo , Feminino , Retardo do Crescimento Fetal/metabolismo , Feto/anormalidades , Feto/metabolismo , Humanos , Troca Materno-Fetal , Obesidade/complicações , Obesidade/metabolismo , Insuficiência Placentária/metabolismo , Gravidez , Gravidez em Diabéticas/metabolismo
6.
Eye (Lond) ; 26(11): 1465-72, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23037910

RESUMO

PURPOSE: We investigated the appearance frequency of eyelid pigmentation and eyelash bristles after the use of five types of prostaglandin (PG) analogs. METHODS: This study included 250 eyes from 250 patients diagnosed with primary open-angle glaucoma or ocular hypertension who were treated with either latanoprost, travoprost, tafluprost, bimatoprost, or isopropyl unoprostone for >3 months in only one eye. Photographs of both eyes were obtained, and the images were assessed by three ophthalmologists who were masked to treatment type. The existence of eyelid pigmentation and eyelash bristles was judged, and images of the left and right eyes were compared. Subjective symptoms regarding the existence of eyelid pigmentation and eyelash bristles were investigated through a questionnaire. RESULTS: There was no significant difference between the five types of medications with regard to eyelid pigmentation (P=0.537). Use of isopropyl unoprostone resulted in a significantly lower incidence of eyelash bristles (P<0.0001). The questionnaire investigation showed that eyelid pigmentation and eyelash bristles were significantly more frequent with travoprost (42.0% and 42.0%, respectively) and bimatoprost (58.0% and 60.0%, respectively) than with other three medications (P<0.0001). CONCLUSION: The appearance frequency of eyelid pigmentation was similar among the five types of PG analogs studied, and eyelash bristles appeared less frequently with isopropyl unoprostone use. Patients are conscious of eyelash bristles; therefore, these adverse effects should be sufficiently explained to patients before PG administration.


Assuntos
Anti-Hipertensivos/efeitos adversos , Pestanas/efeitos dos fármacos , Doenças Palpebrais/induzido quimicamente , Glaucoma de Ângulo Aberto/tratamento farmacológico , Prostaglandinas Sintéticas/efeitos adversos , Pigmentação da Pele/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Amidas/efeitos adversos , Bimatoprost , Cloprostenol/efeitos adversos , Cloprostenol/análogos & derivados , Dinoprosta/efeitos adversos , Dinoprosta/análogos & derivados , Feminino , Humanos , Pressão Intraocular/efeitos dos fármacos , Latanoprosta , Masculino , Pessoa de Meia-Idade , Hipertensão Ocular/tratamento farmacológico , Estudos Prospectivos , Prostaglandinas F/efeitos adversos , Prostaglandinas F Sintéticas/efeitos adversos , Inquéritos e Questionários , Travoprost
7.
Mol Hum Reprod ; 18(5): 253-64, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22180326

RESUMO

Maternal diabetes increases the risk of embryo malformations. Folic acid and safflower oil supplementations have been shown to reduce embryo malformations in experimental models of diabetes. In this study we here tested whether folic acid and safflower oil supplementations interact to prevent embryo malformations in diabetic rats, and analyzed whether they act through the regulation of matrix metalloproteinases (MMPs), their endogenous inhibitors (TIMPs), and nitric oxide (NO) and reactive oxygen species production. Diabetes was induced by streptozotocin administration prior to mating. From Day 0.5 of pregnancy, rats did or did not receive folic acid (15 mg/kg) and/or a 6% safflower oil-supplemented diet. Embryos and decidua were explanted on Day 10.5 of gestation for further analysis of embryo resorptions and malformations, MMP-2 and MMP-9 activities, TIMP-1 and TIMP-2 levels, NO production and lipid peroxidation. Maternal diabetes induced resorptions and malformations that were prevented by folic acid and safflower oil supplementation. MMP-2 and MMP-9 activities were increased in embryos and decidua from diabetic rats and decreased with safflower oil and folic acid supplementations. In diabetic animals, the embryonic and decidual TIMPs were increased mainly with safflower oil supplementation in decidua and with folic acid in embryos. NO overproduction was decreased in decidua from diabetic rats treated with folic acid alone and in combination with safflower oil. These treatments also prevented increases in embryonic and decidual lipid peroxidation. In conclusion, folic acid and safflower oil supplementations interact and protect the embryos from diabetes-induced damage through several pathways related to a decrease in pro-inflammatory mediators.


Assuntos
Diabetes Mellitus Experimental/complicações , Suplementos Nutricionais , Ácido Fólico/uso terapêutico , Gravidez em Diabéticas , Efeitos Tardios da Exposição Pré-Natal/tratamento farmacológico , Substâncias Protetoras/uso terapêutico , Óleo de Cártamo/uso terapêutico , Animais , Anormalidades Congênitas/etiologia , Anormalidades Congênitas/prevenção & controle , Embrião de Mamíferos/efeitos dos fármacos , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Reabsorção do Feto/prevenção & controle , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Óxido Nítrico/metabolismo , Gravidez , Resultado da Gravidez , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
8.
Placenta ; 33(1): 8-16, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22098918

RESUMO

OBJECTIVES: Matrix metalloproteinases (MMPs) are proteolytic enzymes involved in placental development and function, although related to the pro-inflammatory environment when produced in excess. Previous studies have identified MMP-2 and MMP-9 overactivities in the placenta from diabetic rats. In this study, we aimed to determine whether diets supplemented with olive and safflower oil, enriched in natural PPAR ligands, are able to regulate MMP-2 and MMP-9 activities in the placenta and serum from diabetic rats. STUDY DESIGN: Diabetes was induced in rat neonates by streptozotocin administration (90mg/kg s.c.). Control and diabetic rats were fed with 6% olive oil- or 6% safflower oil-supplemented diets from days 0.5-13.5 of gestation. MAIN OUTCOME MEASURES: On day 13.5 of gestation, placentas and sera were isolated for further determination of matrix metalloproteinases (MMPs) 2 and 9 activities by zymography. Placental MMP-2 and MMP-9 protein concentration and immunolocalization were also determined. RESULTS: Sera from diabetic pregnant animals showed MMP-2 and MMP-9 overactivities when compared to controls. Serum MMP-9 activity was significantly decreased when the diabetic animals received the olive and safflower oil dietary treatments. Placentas from diabetic rats showed increased MMP-2 and MMP-9 activities and protein concentrations, and both were decreased when diabetic rats received the olive and safflower dietary treatments. CONCLUSIONS: This study demonstrates that both olive and safflower oil-supplemented diets were able to prevent MMPs overactivities in the placenta from diabetic rats, and that these beneficial effects are reflected in rat sera.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Placenta/metabolismo , Óleos de Plantas/uso terapêutico , Gravidez em Diabéticas/dietoterapia , Óleo de Cártamo/uso terapêutico , Animais , Biomarcadores/sangue , Precursores Enzimáticos/metabolismo , Feminino , Ligantes , Metaloproteinase 2 da Matriz/sangue , Metaloproteinase 9 da Matriz/sangue , Azeite de Oliva , Receptores Ativados por Proliferador de Peroxissomo/agonistas , Placenta/imunologia , Placenta/patologia , Gravidez , Proteínas da Gravidez/sangue , Proteínas da Gravidez/metabolismo , Gravidez em Diabéticas/imunologia , Gravidez em Diabéticas/metabolismo , Gravidez em Diabéticas/patologia , Transporte Proteico , Distribuição Aleatória , Ratos , Ratos Wistar , Estreptozocina
9.
Mol Hum Reprod ; 16(4): 286-95, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20051498

RESUMO

Aberrant arachidonic acid and nitric oxide (NO) metabolic pathways are involved in diabetic embryopathy. Previous works have found diminished concentrations of PGE(2) and PGI(2) in embryos from diabetic rats, and that PGI(2) is capable of increasing embryonic PGE(2) concentrations through the activation of the nuclear receptor PPARdelta. PPARdelta activators are lipid molecules such as oleic and linoleic acids, present in high concentrations in olive and safflower oils, respectively. The aim of this study was to analyze the capability of dietary supplementation with either 6% olive or 6% safflower oils to regulate PGE(2), PGI(2) and NO concentrations in embryos and deciduas from control and diabetic rats during early organogenesis. Diabetes was induced by a single injection of streptozotocin (55 mg/kg) 1 week before mating. Animals were fed with the oil-supplemented diets from Days 0.5 to 10.5 of gestation. PGI(2) and PGE(2) were measured by EIA and NO through the evaluation of its stable metabolites nitrates-nitrites in 10.5 day embryos and deciduas. We found that the olive and safflower oil-supplemented treatments highly reduced resorption and malformation rates in diabetic animals, and that they were able to prevent maternal diabetes-induced alterations in embryonic and decidual PGI(2) and PGE(2) concentrations. Moreover, these dietary treatments prevented NO overproduction in embryos and deciduas from diabetic rats. These data indicate that in maternal diabetes both the embryo and the decidua benefit from the olive and safflower oil supplementation probably through mechanisms that involve the rescue of aberrant prostaglandin and NO generation and that prevent developmental damage during early organogenesis.


Assuntos
Ácido Araquidônico/metabolismo , Gorduras na Dieta/administração & dosagem , Suplementos Nutricionais , Doenças Fetais/prevenção & controle , Óxido Nítrico/metabolismo , Óleos de Plantas/administração & dosagem , Óleo de Cártamo/administração & dosagem , Animais , Diabetes Mellitus Experimental/metabolismo , Dinoprostona/metabolismo , Embrião de Mamíferos/metabolismo , Feminino , Masculino , Modelos Biológicos , Azeite de Oliva , Gravidez , Gravidez em Diabéticas , Ratos , Ratos Wistar
10.
Int Endod J ; 42(12): 1065-70, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19912376

RESUMO

AIM: To establish and compare the relationship between the distance from the file tip to the apical foramen and the numeric meter reading on the display of three different electronic apex locators (EALs). METHODOLOGY: A total of 12 extracted intact, straight, single-rooted human teeth with complete roots were used. The actual root canal length (AL) was determined after access preparation. For the electronic measurements with each EAL, silicon stops were fixed with auto-polymerizing resin to size 15 K-files at AL and 0.5, 1, 2, 3, 4 mm short of AL. The data was analysed by two-way anova and Tukey's honestly significant difference (HSD) test for multiple comparisons amongst EALs. Additionally, one-way anova and Tukey's HSD test were carried out for multiple comparisons amongst the measurements of each EAL. RESULTS: There was a statistically significant difference amongst all EALs in indicating the position of file tips in relation to the major foramen (P < 0.05). The correlation between the meter reading and the position of the file tip from the apical foramen was statistically significant in the three EALs. There were significant differences amongst the measurements at distances from 0 to 2 mm in Justy III. In Dentaport, significant differences were found from 0 to 1 mm. However, the E-Magic Finder showed significant differences from 0 to 0.5 mm. CONCLUSIONS: Justy III was more capable of displaying the intracanal position of the file tip from the major foramen in mm whilst advancing through the root canal during electronic measurements than the Dentaport and E-Magic Finder Deluxe.


Assuntos
Equipamentos Odontológicos , Cavidade Pulpar/anatomia & histologia , Odontometria/instrumentação , Ápice Dentário/anatomia & histologia , Impedância Elétrica , Equipamentos e Provisões Elétricas , Humanos , Preparo de Canal Radicular/instrumentação
11.
Eur J Clin Invest ; 39(12): 1082-90, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19811527

RESUMO

BACKGROUND: Maternal diabetes is associated with morphological placental abnormalities and foeto-placental impairments. These alterations are linked with a dysregulation of the activity of matrix metalloproteinases (MMPs). We investigated the action of 15deoxyDelta(12,14) prostaglandin J(2) (15dPGJ(2)), a natural ligand of the peroxisome proliferator activated receptor (PPAR) gamma, on MMP-2 and MMP-9 activities and tissue inhibitors of matrix metalloproteinases (TIMP) levels in foetuses and placentas from diabetic rats. MATERIALS AND METHODS: Diabetes was induced in rat neonates by a single streptozotocin administration (90 mg kg(-1) s.c.). At 13.5 days of gestation, foetal and placental homogenates were prepared for the determination of PPARgamma levels (western blot) and 15dPGJ(2) concentration (enzyme-immunoassay), whereas the in vitro effect of 15dPGJ(2) (2 microM) was evaluated on placental and foetal MMPs and TIMP activities (zymography and reverse zymography), nitrate/nitrite concentrations (Griess method) and thiobarbituric acid reactive substances (TBARS). RESULTS: PPARgamma was increased while 15dPGJ(2) was decreased in placentas and foetuses from diabetic rats. 15dPGJ(2) additions were able to reduce the high activities of MMP-2 and MMP-9 present in diabetic placental tissues. 15dPGJ(2) additions reduced MMP-2 activity in control and diabetic foetuses. TIMP-3 levels were decreased in diabetic placentas and 15dPGJ(2) was able to enhance them to control values. Nitrates/nitrites and TBARS, metabolites of MMPs activators, were increased in the diabetic placenta and reduced by 15dPGJ(2). CONCLUSIONS: This study demonstrates that 15dPGJ(2) is a potent modulator of the balance between MMP activities and TIMP levels, which is needed in the correct formation and function of the placenta and foetal organs.


Assuntos
Diabetes Mellitus/metabolismo , Feto/efeitos dos fármacos , Metaloproteinases da Matriz/efeitos dos fármacos , PPAR gama/antagonistas & inibidores , Placenta/efeitos dos fármacos , Prostaglandina D2/análogos & derivados , Animais , Diabetes Mellitus/enzimologia , Modelos Animais de Doenças , Feminino , Feto/metabolismo , Gelatinases/metabolismo , Metaloproteinases da Matriz/metabolismo , Óxido Nítrico/metabolismo , PPAR gama/metabolismo , Placenta/metabolismo , Gravidez , Prostaglandina D2/metabolismo , Prostaglandina D2/farmacologia , Ratos , Ratos Wistar , Inibidores Teciduais de Metaloproteinases/efeitos dos fármacos , Inibidores Teciduais de Metaloproteinases/metabolismo
12.
Artigo em Inglês | MEDLINE | ID: mdl-18947987

RESUMO

Maternal diabetes impairs fetal development and growth. We studied the effects of maternal diets enriched in unsaturated fatty acids capable of activating peroxisome proliferator-activated receptors (PPARs) on the concentrations of 15deoxyDelta12,14PGJ2 (15dPGJ2), lipid mass, and the de novo lipid synthesis in 13.5-day fetuses from control and diabetic rats. Diabetes was induced by neonatal streptozotocin administration (90 mg/kg). Rats were treated with a standard diet supplemented or not with 6% olive oil or 6% safflower oil from days 0.5 to 13.5 of gestation. Fetuses from diabetic rats fed with the standard diet showed reduced 15dPGJ2 concentrations, whereas maternal treatments with olive and safflower oils increased 15dPGJ2 concentrations. Fetuses from diabetic rats showed increased concentrations of phospholipids and increased synthesis of triglycerides, phospholipids, cholesterol and free fatty acids. Diabetic rat treatments with olive and safflower oils reduced phospholipids, cholesterol, and free fatty acid concentrations and the de novo lipid synthesis in the fetuses. These effects were different from those observed in fetuses from control rats, and seem not to involve PPARgamma activation. In conclusion, olive oil- and safflower oil-supplemented diets provide beneficial effects in maternal diabetes, as they prevent fetal impairments in 15dPGJ2 concentrations, lipid synthesis and lipid accumulation.


Assuntos
Feto/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Receptores Ativados por Proliferador de Peroxissomo/agonistas , Animais , Animais Recém-Nascidos , Colesterol/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/farmacologia , Ácidos Graxos não Esterificados/metabolismo , Ácidos Graxos Insaturados/administração & dosagem , Ácidos Graxos Insaturados/farmacologia , Feminino , Feto/metabolismo , Masculino , Azeite de Oliva , Óleos de Plantas/administração & dosagem , Óleos de Plantas/farmacologia , Gravidez , Ratos , Óleo de Cártamo/administração & dosagem , Óleo de Cártamo/farmacologia , Estreptozocina , Triglicerídeos/metabolismo
13.
Genet Mol Res ; 7(3): 898-909, 2008 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-18949708

RESUMO

Computational methods for predicting protein-protein interaction sites based on structural data are characterized by an accuracy between 70 and 80%. Some experimental studies indicate that only a fraction of the residues, forming clusters in the center of the interaction site, are energetically important for binding. In addition, the analysis of amino acid composition has shown that residues located in the center of the interaction site can be better discriminated from the residues in other parts of the protein surface. In the present study, we implement a simple method to predict interaction site residues exploiting this fact and show that it achieves a very competitive performance compared to other methods using the same dataset and criteria for performance evaluation (success rate of 82.1%).


Assuntos
Biologia Computacional/métodos , Proteínas/química , Análise de Sequência de Proteína/métodos , Sítios de Ligação , Ligação Proteica , Conformação Proteica , Mapeamento de Interação de Proteínas
14.
Reproduction ; 136(1): 95-103, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18417641

RESUMO

Maternal diabetes promotes an overaccumulation of lipids in the feto-placental unit and impairs feto-placental development and growth. Here, we investigated the role played by the nuclear receptor peroxisome proliferator-activated receptor (PPAR)alpha in lipid metabolism in fetuses and placentas from control and neonatal streptozotocin-induced diabetic rats. Placentas and fetuses were studied on day 13.5 of gestation. The concentrations of PPARalpha (by Western blot) and its endogenous agonist leukotriene B(4) (LTB(4)) (by enzyme immunoassay) were analysed. Placental explants and fetuses were cultured with LTB(4) or clofibrate, and then lipid metabolism analysed (concentrations and synthesis from (14)C-acetate of triglycerides, phospholipids, cholesterol and cholesteryl esters; release of glycerol and free fatty acids (FFAs)). We found that maternal diabetes led to increases in placental concentrations of triglycerides and cholesteryl esters, and fetal concentrations of phospholipids. PPARalpha agonists downregulated fetal and placental lipid concentrations in control and diabetic rats. The synthesis of lipids was reduced in the diabetic placenta but increased in fetuses from diabetic animals. PPARalpha agonists reduced the synthesis of lipids in control placenta and in the fetuses from control and diabetic rats. Glycerol and FFA release was enhanced in the diabetic placenta and in control placenta cultured with PPARalpha agonists. Maternal diabetes led to reductions in fetal and placental LTB(4) concentrations and to increases in placental PPARalpha concentrations. Overall, these data support a novel role of PPARalpha as a regulator of lipid metabolism in the feto-placental unit, relevant in maternal diabetes where fetal and placental PPARalpha, LTB(4) and lipid concentrations are altered.


Assuntos
Diabetes Gestacional/metabolismo , Feto/metabolismo , Metabolismo dos Lipídeos , PPAR alfa/metabolismo , Placenta/metabolismo , Animais , Ácidos Graxos não Esterificados/análise , Feminino , Glicerol/análise , Leucotrieno B4/análise , Leucotrieno B4/metabolismo , Lipídeos/análise , Lipídeos/biossíntese , PPAR alfa/análise , Gravidez , Ratos , Ratos Wistar
15.
Reproduction ; 134(4): 605-13, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17890296

RESUMO

Matrix metalloproteinases (MMPs) play an important role in tissue remodeling that accompanies the rapid growth, differentiation, and structural changes of the placenta and several fetal organs. In the present study, we investigated whether the diabetic maternal environment may alter the regulatory homeostasis exerted by nitric oxide (NO) on MMPs activity in the feto-placental unit from rats at midgestation. We found that NADPH-diaphorase activity, which reflects the distribution and activity of NO synthases (NOS), was increased in both placenta and fetuses from diabetic rats when compared with controls. In addition, while a NO donor enhanced MMP2 and MMP9 activities, a NOS inhibitor reduced these activities in the maternal side of the placenta from control rats. This regulatory effect of NO was only observed on MMP9 in the diabetic group. On the other hand, the NO donor did not modify MMP2 and MMP9 activities, while the NOS inhibitor reduced MMP9 activity in the fetal side of both control and diabetic placentas. In the fetuses, MMP2 was enhanced by the NO donor and reduced by the NO inhibitor in both fetuses from control and diabetic rats. Overall, this study demonstrates that NO is able to modulate the activation of MMPs in the feto-placental unit, and provides supportive evidence that increased NOS activity leads to NO overproduction in the feto-placental unit from diabetic rats, an alteration closely related to the observed MMPs dysregulation that may have profound implications in the formation and function of the placenta and the fetal organs.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Feto/enzimologia , Metaloproteinases da Matriz/metabolismo , Óxido Nítrico/fisiologia , Placenta/enzimologia , Animais , Western Blotting/métodos , Eletroforese em Gel de Poliacrilamida , Feminino , Feto/efeitos dos fármacos , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/análise , Metaloproteinase 9 da Matriz/metabolismo , Metaloproteinases da Matriz/análise , NG-Nitroarginina Metil Éster/farmacologia , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/análise , Óxido Nítrico Sintase Tipo III/análise , Nitroprussiato/farmacologia , Placenta/efeitos dos fármacos , Gravidez , Ratos , Ratos Wistar
16.
Mol Hum Reprod ; 13(2): 103-10, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17148578

RESUMO

Maternal diabetes significantly increases the risk of congenital malformations, and the mechanisms involved are not yet clarified. This study was designed to address peroxisome proliferator-activated receptor delta (PPARdelta) involvement in diabetic embryopathy. We investigated the concentrations of PPARdelta and its endogenous agonist prostaglandin (PG)I(2), as well as the effect of PPARdelta activation on lipid metabolism and PGE(2) concentrations in embryos from control and streptozotocin-induced diabetic rats during early organogenesis. Embryos from diabetic rats showed decreased concentrations of PPARdelta and its endogenous agonist PGI(2) when compared with controls. In embryos from control rats, the addition of the PPARdelta activators (cPGI(2) and PGA(1)) increased embryonic phospholipid levels and de novo phospholipid synthesis studied using (14)C-acetate as a tracer. PGE(2) formed from arachidonate released from phospholipid stores was also up-regulated by PPARdelta activators. In embryos from diabetic rats, reduced phospholipid synthesis and PGE(2) content were observed, and clearly up-regulated by cPGI(2) additions to values similar to those found in control embryos. These data suggest that PPARdelta may play an important role in lipid metabolic and signalling pathways during embryo organogenesis, developmental pathways that are altered in embryos from diabetic rats, possibly as a result of a reduction in levels of PPARdelta and its endogenous activator PGI(2).


Assuntos
Diabetes Mellitus Experimental/embriologia , Epoprostenol/metabolismo , Doenças Fetais/metabolismo , Metabolismo dos Lipídeos , Organogênese , PPAR delta/metabolismo , Prenhez , Animais , Dinoprostona/análise , Técnicas de Cultura Embrionária , Embrião de Mamíferos/anatomia & histologia , Embrião de Mamíferos/metabolismo , Epoprostenol/farmacologia , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Doenças Fetais/induzido quimicamente , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , PPAR delta/fisiologia , Gravidez , Gravidez em Diabéticas , Ratos , Ratos Wistar , Transdução de Sinais , Estreptozocina
17.
Genet Mol Res ; 5(4): 717-22, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17183482

RESUMO

Star STING is the latest version of the STING suite of programs and corresponding database. We report on five important aspects of this package that have acquired some new characteristics, designed to add key advantages to the whole suite: 1) availability for most popular platforms and browsers, 2) introduction of the STING_DB quality assessment, 3) improvement in algorithms for calculation of three STING parameters, 4) introduction of five new STING modules, and 5) expansion of the existing modules. Star STING is freely accessible at: http://sms.cbi.cnptia.embrapa.br/SMS/, http://trantor.bioc.columbia.edu/SMS, http://www.es.embnet.org/SMS/, http://gibk26.bse.kyutech.ac.jp/SMS/ and http://www.ar.embnet.org/SMS.


Assuntos
Bases de Dados de Proteínas , Proteínas/química , Análise de Sequência de Proteína , Software , Algoritmos , Gráficos por Computador , Modelos Moleculares , Estrutura Molecular
18.
Genet. mol. res. (Online) ; 5(1): 193-202, Mar. 31, 2006. graf, tab
Artigo em Inglês | LILACS | ID: lil-449133

RESUMO

Predicting enzyme class from protein structure parameters is a challenging problem in protein analysis. We developed a method to predict enzyme class that combines the strengths of statistical and data-mining methods. This method has a strong mathematical foundation and is simple to implement, achieving an accuracy of 45%. A comparison with the methods found in the literature designed to predict enzyme class showed that our method outperforms the existing methods.


Assuntos
Humanos , Conformação Proteica , Enzimas/química , Enzimas/classificação , Teorema de Bayes , Algoritmos , Alinhamento de Sequência
19.
Genet. mol. res. (Online) ; 5(1): 127-137, Mar. 31, 2006. ilus, graf
Artigo em Inglês | LILACS | ID: lil-449139

RESUMO

Homology-derived secondary structure of proteins (HSSP) is a well-known database of multiple sequence alignments (MSAs) which merges information of protein sequences and their three-dimensional structures. It is available for all proteins whose structure is deposited in the PDB. It is also used by STING and (Java)Protein Dossier to calculate and present relative entropy as a measure of the degree of conservation for each residue of proteins whose structure has been solved and deposited in the PDB. However, if the STING and (Java)Protein Dossier are to provide support for analysis of protein structures modeled in computers or being experimentally solved but not yet deposited in the PDB, then we need a new method for building alignments having a flavor of HSSP alignments (myMSAr). The present study describes a new method and its corresponding databank (SH2QS--database of sequences homologue to the query [structure-having] sequence). Our main interest in making myMSAr was to measure the degree of residue conservation for a given query sequence, regardless of whether it has a corresponding structure deposited in the PDB. In this study, we compare the measurement of residue conservation provided by corresponding alignments produced by HSSP and SH2QS. As a case study, we also present two biologically relevant examples, the first one highlighting the equivalence of analysis of the degree of residue conservation by using HSSP or SH2QS alignments, and the second one presenting the degree of residue conservation for a structure modeled in a computer, which , as a consequence, does not have an alignment reported by HSSP.


Assuntos
Humanos , Alinhamento de Sequência/métodos , Estrutura Secundária de Proteína/genética , Sequência Conservada/genética , Entropia , Modelos Genéticos , Sequência de Aminoácidos/genética
20.
Genet. mol. res. (Online) ; 5(4): 717-722, 2006. ilus, graf
Artigo em Inglês | LILACS | ID: lil-482084

RESUMO

Star STING is the latest version of the STING suite of programs and corresponding database. We report on five important aspects of this package that have acquired some new characteristics, designed to add key advantages to the whole suite: 1) availability for most popular platforms and browsers, 2) introduction of the STING_DB quality assessment, 3) improvement in algorithms for calculation of three STING parameters, 4) introduction of five new STING modules, and 5) expansion of the existing modules. Star STING is freely accessible at: http://sms.cbi.cnptia.embrapa.br/SMS/, http://trantor.bioc.columbia.edu/SMS, http://www.es.embnet.org/SMS/, http://gibk26.bse.kyutech.ac.jp/SMS/ and http://www.ar.embnet.org/SMS.


Assuntos
Bases de Dados de Proteínas , Proteínas/química , Análise de Sequência de Proteína , Software , Algoritmos , Gráficos por Computador , Modelos Moleculares , Estrutura Molecular
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