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1.
Pregnancy Hypertens ; 23: 211-219, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33530034

RESUMO

Preeclampsia is a pregnancy-specific disorder characterized by hypertension and dysfunction of several organs, that is associated with maternal and fetal complications. The human gut microbiota is related to health and disease including hypertension. Alterations in gut microbiota composition can change the short-chain fatty acid profile released by the bacteria and contribute to hypertension and metabolic syndrome. It is unclear if the composition of the gut microbiota is altered in women who develop late-onset preeclampsia. In this study, we investigated the composition of the gut microbiota at 28 weeks gestation in women who developed late-onset (>34 weeks gestation) preeclampsia (DPE) by 16S rRNA gene amplicon sequencing of fecal samples obtained from 213 pregnant women in the SPRING cohort (Study of Probiotics IN Gestational diabetes). Quantitative real-time PCR was used to assess the density of butyrate-producing genes. Gut microbiota composition was compared between women with and without DPE. The abundance of the butyrate-producing Coprococcus genus significantly decreased in DPE. Abundance of Coprococcus is significantly and positively correlated with the abundance of genes encoding the terminal step in bacterial butyrate formation (but and buk). Women with DPE also had significantly reduced levels of serum butyrate prior to the development of symptoms than controls. This study suggests that a reduction in the abundance of butyrate-producing bacteria, and Coprococcus spp. in particular, may contribute to an increased risk of developing preeclampsia in pregnant women.


Assuntos
Microbioma Gastrointestinal , Pré-Eclâmpsia/microbiologia , Adulto , Butiratos/metabolismo , Clostridiales/isolamento & purificação , Estudos de Coortes , Fezes/microbiologia , Feminino , Humanos , Obesidade/complicações , Pré-Eclâmpsia/prevenção & controle , Gravidez
2.
Sci Rep ; 11(1): 1480, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33452289

RESUMO

Brewing science is undergoing a renaissance with the use of modern analytical chemistry and microbiology techniques. However, these modern analytical tools and techniques are not necessarily aligned with the scale and scope of brewing science. In particular, brewing processes can be time consuming, ingredient intensive, and require specialised technical equipment. These drawbacks compound with the need for appropriate numbers of replicates for adequately powered experimental design. Here, we describe a micro-scale mash method that can be performed using a common laboratory benchtop shaker/incubator, allowing for high throughput mashing and easy sample replication for statistical analysis. Proteomic profiles at both the protein and peptide levels were consistent between the 1 mL micro-mash and a 23 L Braumeister mash, and both mash scales produced wort with equivalent fermentable sugar and free amino acid profiles. The experimental flexibility offered by our micro-mash method allowed us to investigate the effects of altered mash parameters on the beer brewing proteome.

3.
Behav Pharmacol ; 30(5): 383-395, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30379647

RESUMO

Behavioural sensitization is a putative mechanism in the pathophysiology of drug addiction and neuropsychiatric disorders such as schizophrenia. In rodents, drug-induced behavioural sensitization has been described for several different drug classes. The N-methyl-D-aspartate receptor antagonist MK-801 can inhibit sensitization to other drugs of abuse. However, MK-801 also produces behavioural sensitization to its own hyperlocomotor inducing effects, suggesting that MK-801 sensitization has a distinctive mechanism of action. The aim of this study was to carry out a functional and molecular analysis of the nucleus accumbens (NAc) of adult male Sprague-Dawley rats sensitized to MK-801 (seven daily injections of 0.25 mg/kg, 5 days of withdrawal and subsequent 0.25 mg/kg challenge), or following acute MK-801 (0.25 mg/kg), or naive rats as controls. Locomotor activity was the primary measure of sensitization. Ex-vivo slice electrophysiology showed a decrease in the excitatory synaptic strength in the NAc of rats sensitized to MK-801 compared with acute MK-801 treatment or naive controls. An LC-MS/MS SWATH proteomics approach showed that proteins altered by MK-801 sensitization were predominantly related to functions including calcium and glutamate signalling, and mitochondrial dysfunction. These results shed some light on neural changes in the NAc after sensitization to MK-801. This model could prove useful for studying the role of N-methyl-D-aspartate receptors in the pathophysiology of drug addiction and schizophrenia.


Assuntos
Maleato de Dizocilpina/farmacologia , Tolerância a Medicamentos/fisiologia , Núcleo Accumbens/metabolismo , Animais , Estimulantes do Sistema Nervoso Central/farmacologia , Cromatografia Líquida , Relação Dose-Resposta a Droga , Antagonistas de Aminoácidos Excitatórios/farmacologia , Locomoção/efeitos dos fármacos , Masculino , Atividade Motora/efeitos dos fármacos , Núcleo Accumbens/fisiologia , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/agonistas , Receptores de N-Metil-D-Aspartato/metabolismo , Espectrometria de Massas em Tandem
4.
J Mol Evol ; 86(8): 531-545, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30206667

RESUMO

The Asian genus Boiga (Colubridae) is among the better studied non-front-fanged snake lineages, because their bites have minor, but noticeable, effects on humans. Furthermore, B. irregularis has gained worldwide notoriety for successfully invading Guam and other nearby islands with drastic impacts on the local bird populations. One of the factors thought to allow B. irregularis to become such a noxious pest is irditoxin, a dimeric neurotoxin composed of two three-finger toxins (3FTx) joined by a covalent bond between two newly evolved cysteines. Irditoxin is highly toxic to diapsid (birds and reptiles) prey, but roughly 1000 × less potent to synapsids (mammals). Venom plays an important role in the ecology of all species of Boiga, but it remains unknown if any species besides B. irregularis produce irditoxin-like dimeric toxins. In this study, we use transcriptomic analyses of venom glands from five species [B. cynodon, B. dendrophila dendrophila, B. d. gemmicincta, B. irregularis (Brisbane population), B. irregularis (Sulawesi population), B. nigriceps, B. trigonata] and proteomic analyses of B. d. dendrophila and a representative of the sister genus Toxicodryas blandingii to investigate the evolutionary history of 3FTx within Boiga and its close relative. We found that 92.5% of Boiga 3FTx belong to a single clade which we refer to as denmotoxin-like because of the close relation between these toxins and the monomeric denmotoxin according to phylogenetic, sequence clustering, and protein similarity network analyses. We show for the first time that species beyond B. irregularis secrete 3FTx with additional cysteines in the same position as both the A and B subunits of irditoxin. Transcripts with the characteristic mutations are found in B. d. dendrophila, B. d. gemmicincta, B. irregularis (Brisbane population), B. irregularis (Sulawesi population), and B. nigriceps. These results are confirmed by proteomic analyses that show direct evidence of dimerization within the venom of B. d. dendrophila, but not T. blandingii. Our results also suggest the possibility of novel dimeric toxins in other genera such as Telescopus and Trimorphodon. All together, this suggests that the origin of these peculiar 3FTx is far earlier than was appreciated and their evolutionary history has been complex.


Assuntos
Neurotoxinas/análise , Proteômica/métodos , Peçonhas/química , Animais , Colubridae , Guam , Neurotoxinas/metabolismo , Filogenia
5.
Artigo em Inglês | MEDLINE | ID: mdl-29074260

RESUMO

While some US populations of the Mohave rattlesnake (Crotalus scutulatus scutulatus) are infamous for being potently neurotoxic, the Mexican subspecies C. s. salvini (Huamantlan rattlesnake) has been largely unstudied beyond crude lethality testing upon mice. In this study we show that at least some populations of this snake are as potently neurotoxic as its northern cousin. Testing of the Mexican antivenom Antivipmyn showed a complete lack of neutralisation for the neurotoxic effects of C. s. salvini venom, while the neurotoxic effects of the US subspecies C. s. scutulatus were time-delayed but ultimately not eliminated. These results document unrecognised potent neurological effects of a Mexican snake and highlight the medical importance of this subspecies, a finding augmented by the ineffectiveness of the Antivipmyn antivenom. These results also influence our understanding of the venom evolution of Crotalus scutulatus, suggesting that neurotoxicity is the ancestral feature of this species, with the US populations which lack neurotoxicity being derived states.


Assuntos
Venenos de Crotalídeos/metabolismo , Crotalus/fisiologia , Evolução Molecular , Músculo Esquelético/efeitos dos fármacos , Bloqueadores Neuromusculares/metabolismo , Neurotoxinas/metabolismo , Proteínas de Répteis/metabolismo , Animais , Antivenenos/farmacologia , Arizona , Galinhas , Venenos de Crotalídeos/antagonistas & inibidores , Venenos de Crotalídeos/química , Venenos de Crotalídeos/toxicidade , Crotalus/crescimento & desenvolvimento , Clima Desértico , Feminino , Técnicas In Vitro , Dose Letal Mediana , Masculino , México , Camundongos Endogâmicos BALB C , Contração Muscular/efeitos dos fármacos , Músculo Esquelético/inervação , Bloqueadores Neuromusculares/antagonistas & inibidores , Bloqueadores Neuromusculares/química , Bloqueadores Neuromusculares/toxicidade , Neurotoxinas/antagonistas & inibidores , Neurotoxinas/química , Neurotoxinas/toxicidade , Fosfolipases A2/química , Fosfolipases A2/metabolismo , Fosfolipases A2/toxicidade , Proteômica/métodos , Proteínas de Répteis/antagonistas & inibidores , Proteínas de Répteis/química , Proteínas de Répteis/toxicidade , Especificidade da Espécie , Especificidade por Substrato , Texas
6.
Insect Biochem Mol Biol ; 90: 14-22, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28918158

RESUMO

The Australian sheep blowfly, Lucilia cuprina, is a primary cause of sheep flystrike and a major agricultural pest. Cytochrome P450 enzymes have been implicated in the resistance of L. cuprina to several classes of insecticides. In particular, CYP6G3 is a L. cuprina homologue of Drosophila melanogaster CYP6G1, a P450 known to confer multi-pesticide resistance. To investigate the basis of resistance, a bicistronic Escherichia coli expression system was developed to co-express active L. cuprina CYP6G3 and house fly (Musca domestica) P450 reductase. Recombinant CYP6G3 showed activity towards the high-throughput screening substrates, 7-ethoxycoumarin and p-nitroanisole, but not towards p-nitrophenol, coumarin, 7-benzyloxyresorufin, or seven different luciferin derivatives (P450-Glo™ substrates). The addition of house fly cytochrome b5 enhanced the kcat for p-nitroanisole dealkylation approximately two fold (17.8 ± 0.5 vs 9.6 ± 0.2 min-1) with little effect on KM (13 ± 1 vs 10 ± 1 µM). Inhibition studies and difference spectroscopy revealed that the organochlorine compounds, DDT and endosulfan, and the organophosphate pesticides, malathion and chlorfenvinphos, bind to the active site of CYP6G3. All four pesticides showed type I binding spectra with spectral dissociation constants in the micromolar range suggesting that they may be substrates of CYP6G3. While no significant inhibition was seen with the organophosphate, diazinon, or the neonicotinoid, imidacloprid, diazinon showed weak binding in spectral assays, with a Kd value of 23 ± 3 µM CYP6G3 metabolised diazinon to the diazoxon and hydroxydiazinon metabolites and imidacloprid to the 5-hydroxy and olefin metabolites, consistent with a proposed role of CYP6G enzymes in metabolism of phosphorothioate and neonicotinoid insecticides in other species.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Dípteros/enzimologia , O-Dealquilase 7-Alcoxicumarina/metabolismo , Animais , Diazinon/metabolismo , Proteínas de Insetos/metabolismo , Resistência a Inseticidas , Inseticidas/metabolismo , Ligantes , Neonicotinoides/metabolismo , Nitrocompostos/metabolismo , Proteínas Recombinantes/biossíntese
7.
Mol Cell Neurosci ; 84: 100-111, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28784263

RESUMO

In neurosecretory cells, myosin VI associated with secretory granules (SGs) mediates their activity-dependent recruitment to the cortical actin network and is necessary to sustain exocytosis. The mechanism by which myosin VI interacts with SGs is unknown. Using a myosin VI pull-down assay and mass spectrometry we identified Mena, a member of the ENA/VASP family, as a myosin VI binding partner in PC12 cells, and confirmed that Mena colocalized with myosin VI on SGs. Using a knock-sideways approach to inactivate the ENA/VASP family members by mitochondrial relocation, we revealed a concomitant redistribution of myosin VI. This was ensued by a reduction in the association of myosin VI with SGs, a decreased SG mobility and density in proximity to the plasma membrane as well as decreased evoked exocytosis. These data demonstrate that ENA/VASP proteins regulate SG exocytosis through modulating the activity of myosin VI.


Assuntos
Actinas/metabolismo , Proteínas de Ligação a DNA/metabolismo , Exocitose/fisiologia , Vesículas Secretórias/metabolismo , Animais , Moléculas de Adesão Celular/metabolismo , Membrana Celular/metabolismo , Proteínas dos Microfilamentos/metabolismo , Células PC12 , Fosfoproteínas/metabolismo , Ratos
8.
Toxins (Basel) ; 8(10)2016 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-27763551

RESUMO

Millions of years of evolution have fine-tuned the ability of venom peptides to rapidly incapacitate both prey and potential predators. Toxicofera reptiles are characterized by serous-secreting mandibular or maxillary glands with heightened levels of protein expression. These glands are the core anatomical components of the toxicoferan venom system, which exists in myriad points along an evolutionary continuum. Neofunctionalisation of toxins is facilitated by positive selection at functional hotspots on the ancestral protein and venom proteins have undergone dynamic diversification in helodermatid and varanid lizards as well as advanced snakes. A spectacular point on the venom system continuum is the long-glanded blue coral snake (Calliophis bivirgatus), a specialist feeder that preys on fast moving, venomous snakes which have both a high likelihood of prey escape but also represent significant danger to the predator itself. The maxillary venom glands of C. bivirgatus extend one quarter of the snake's body length and nestle within the rib cavity. Despite the snake's notoriety its venom has remained largely unstudied. Here we show that the venom uniquely produces spastic paralysis, in contrast to the flaccid paralysis typically produced by neurotoxic snake venoms. The toxin responsible, which we have called calliotoxin (δ-elapitoxin-Cb1a), is a three-finger toxin (3FTx). Calliotoxin shifts the voltage-dependence of NaV1.4 activation to more hyperpolarised potentials, inhibits inactivation, and produces large ramp currents, consistent with its profound effects on contractile force in an isolated skeletal muscle preparation. Voltage-gated sodium channels (NaV) are a particularly attractive pharmacological target as they are involved in almost all physiological processes including action potential generation and conduction. Accordingly, venom peptides that interfere with NaV function provide a key defensive and predatory advantage to a range of invertebrate venomous species including cone snails, scorpions, spiders, and anemones. Enhanced activation or delayed inactivation of sodium channels by toxins is associated with the extremely rapid onset of tetanic/excitatory paralysis in envenomed prey animals. A strong selection pressure exists for the evolution of such toxins where there is a high chance of prey escape. However, despite their prevalence in other venomous species, toxins causing delay of sodium channel inhibition have never previously been described in vertebrate venoms. Here we show that NaV modulators, convergent with those of invertebrates, have evolved in the venom of the long-glanded coral snake. Calliotoxin represents a functionally novel class of 3FTx and a structurally novel class of NaV toxins that will provide significant insights into the pharmacology and physiology of NaV. The toxin represents a remarkable case of functional convergence between invertebrate and vertebrate venom systems in response to similar selection pressures. These results underscore the dynamic evolution of the Toxicofera reptile system and reinforces the value of using evolution as a roadmap for biodiscovery.


Assuntos
Venenos Elapídicos/farmacologia , Elapidae , Canal de Sódio Disparado por Voltagem NAV1.4/fisiologia , Neurotoxinas/farmacologia , Agonistas do Canal de Sódio Disparado por Voltagem/farmacologia , Animais , Linhagem Celular Tumoral , Galinhas , Venenos Elapídicos/toxicidade , Células HEK293 , Humanos , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/inervação , Músculo Esquelético/fisiologia , Neurotoxinas/toxicidade , Agonistas do Canal de Sódio Disparado por Voltagem/toxicidade
9.
Toxins (Basel) ; 8(11)2016 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-27792190

RESUMO

Australia is the stronghold of the front-fanged venomous snake family Elapidae. The Australasian elapid snake radiation, which includes approximately 100 terrestrial species in Australia, as well as Melanesian species and all the world's sea snakes, is less than 12 million years old. The incredible phenotypic and ecological diversity of the clade is matched by considerable diversity in venom composition. The clade's evolutionary youth and dynamic evolution should make it of particular interest to toxinologists, however, the majority of species, which are small, typically inoffensive, and seldom encountered by non-herpetologists, have been almost completely neglected by researchers. The present study investigates the venom composition of 28 species proteomically, revealing several interesting trends in venom composition, and reports, for the first time in elapid snakes, the existence of an ontogenetic shift in the venom composition and activity of brown snakes (Pseudonaja sp.). Trends in venom composition are compared to the snakes' feeding ecology and the paper concludes with an extended discussion of the selection pressures shaping the evolution of snake venom.


Assuntos
Venenos Elapídicos , Animais , Austrália , Coagulação Sanguínea/efeitos dos fármacos , Venenos Elapídicos/química , Venenos Elapídicos/genética , Venenos Elapídicos/toxicidade , Elapidae/genética , Elapidae/fisiologia , Evolução Molecular , Feminino , Humanos , Masculino , Comportamento Predatório
10.
Appl Environ Microbiol ; 81(14): 4573-80, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25934616

RESUMO

Wolbachia bacteria are endosymbionts that infect approximately 40% of all insect species and are best known for their ability to manipulate host reproductive systems. Though the effect Wolbachia infection has on somatic tissues is less well understood, when present in cells of the adult Drosophila melanogaster brain, Wolbachia exerts an influence over behaviors related to olfaction. Here, we show that a strain of Wolbachia influences male aggression in flies, which is critically important in mate competition. A specific strain of Wolbachia was observed to reduce the initiation of aggressive encounters in Drosophila males compared to the behavior of their uninfected controls. To determine how Wolbachia was able to alter aggressive behavior, we investigated the role of octopamine, a neurotransmitter known to influence male aggressive behavior in many insect species. Transcriptional analysis of the octopamine biosynthesis pathway revealed that two essential genes, the tyrosine decarboxylase and tyramine ß-hydroxylase genes, were significantly downregulated in Wolbachia-infected flies. Quantitative chemical analysis also showed that total octopamine levels were significantly reduced in the adult heads.


Assuntos
Drosophila melanogaster/microbiologia , Drosophila melanogaster/fisiologia , Octopamina/biossíntese , Wolbachia/fisiologia , Animais , Comportamento Animal , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimologia , Drosophila melanogaster/genética , Feminino , Masculino , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Tirosina Descarboxilase/genética , Tirosina Descarboxilase/metabolismo
11.
BMC Vet Res ; 10: 211, 2014 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-25350131

RESUMO

BACKGROUND: The ghrelin axis is involved in the regulation of metabolism, energy balance, and the immune, cardiovascular and reproductive systems. The manipulation of this axis has potential for improving economically valuable traits in production animals, and polymorphisms in the ghrelin (GHRL) and ghrelin receptor (GHSR) genes have been associated with growth and carcass traits. Here we investigate the structure and expression of the ghrelin gene (GHRL) in sheep, Ovis aries. RESULTS: We identify two ghrelin mRNA isoforms, which we have designated Δex2 preproghrelin and Δex2,3 preproghrelin. Expression of Δex2,3 preproghrelin is likely to be restricted to ruminants, and would encode truncated ghrelin and a novel C-terminal peptide. Both Δex2 preproghrelin and canonical preproghrelin mRNA isoforms were expressed in a range of tissues. Expression of the Δex2,3 preproghrelin isoform, however, was restricted to white blood cells (WBC; where the wild-type preproghrelin isoform is not co-expressed), and gastrointestinal tissues. Expression of Δex2 preproghrelin and Δex2,3 preproghrelin mRNA was elevated in white blood cells in response to parasitic worm (helminth) infection in genetically susceptible sheep, but not in resistant sheep. CONCLUSIONS: The restricted expression of the novel preproghrelin variants and their distinct WBC expression pattern during parasite infection may indicate a novel link between the ghrelin axis and metabolic and immune function in ruminants.


Assuntos
Clonagem Molecular , Grelina/metabolismo , Hemoncose/veterinária , Doenças dos Ovinos/metabolismo , Sequência de Aminoácidos , Animais , Regulação da Expressão Gênica , Predisposição Genética para Doença , Grelina/genética , Hemoncose/genética , Hemoncose/metabolismo , Haemonchus , Leucócitos/metabolismo , Dados de Sequência Molecular , Isoformas de Proteínas , Ovinos , Doenças dos Ovinos/genética
12.
Int J Oncol ; 43(2): 566-74, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23722988

RESUMO

The molecular mechanisms involved in non­small cell lung cancer tumourigenesis are largely unknown; however, recent studies have suggested that long non-coding RNAs (lncRNAs) are likely to play a role. In this study, we used public databases to identify an mRNA-like, candidate long non-coding RNA, GHSROS (GHSR opposite strand), transcribed from the antisense strand of the ghrelin receptor gene, growth hormone secretagogue receptor (GHSR). Quantitative real-time RT-PCR revealed higher expression of GHSROS in lung cancer tissue compared to adjacent, non-tumour lung tissue. In common with many long non-coding RNAs, GHSROS is 5' capped and 3' polyadenylated (mRNA-like), lacks an extensive open reading frame and harbours a transposable element. Engineered overexpression of GHSROS stimulated cell migration in the A549 and NCI-H1299 non-small cell lung cancer cell lines, but suppressed cell migration in the Beas-2B normal lung-derived bronchoepithelial cell line. This suggests that GHSROS function may be dependent on the oncogenic context. The identification of GHSROS, which is expressed in lung cancer and stimulates cell migration in lung cancer cell lines, contributes to the growing number of non-coding RNAs that play a role in the regulation of tumourigenesis and metastatic cancer progression.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , RNA Longo não Codificante/genética , Receptores de Grelina/genética , Sequência de Bases , Carcinogênese/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Metástase Neoplásica , Análise de Sequência de DNA , Transfecção
13.
Biopolymers ; 98(4): 357-66, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23193600

RESUMO

The study of biologically active peptides is critical to the understanding of physiological pathways, especially those involved in the development of disease. Historically, the measurement of biologically active endogenous peptides has been undertaken by radioimmunoassay, a highly sensitive and robust technique that permits the detection of physiological concentrations in different biofluid and tissue extracts. Over recent years, a range of mass spectrometric approaches have been applied to peptide quantification with limited degrees of success. Neuropeptide Y (NPY), peptide YY (PYY), and pancreatic polypeptide (PP) belong to the NPY family exhibiting regulatory effects on appetite and feeding behavior. The physiological significance of these peptides depends on their molecular forms and in vivo concentrations systemically and at local sites within tissues. In this report, we describe an approach for quantification of individual peptides within mixtures using high-performance liquid chromatography electrospray ionization tandem mass spectrometry analysis of the NPY family peptides. Aspects of quantification including sample preparation, the use of matrix-matched calibration curves, and internal standards will be discussed. This method for the simultaneous determination of NPY, PYY, and PP was accurate and reproducible but lacks the sensitivity required for measurement of their endogenous concentration in plasma. The advantages of mass spectrometric quantification will be discussed alongside the current obstacles and challenges.


Assuntos
Espectrometria de Massas/métodos , Neuropeptídeo Y/química , Peptídeos/química , Cromatografia Líquida , Polipeptídeo Pancreático/química , Peptídeo YY/química
14.
Mol Cell Endocrinol ; 340(1): 65-9, 2011 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-21616120

RESUMO

Ghrelin is a peptide hormone that was originally isolated from the stomach as the endogenous ligand for the growth hormone secretagogue receptor (GHSR). Ghrelin has many functions, including the regulation of appetite and gut motility, growth hormone release from the anterior pituitary and roles in the cardiovascular and immune systems. Ghrelin and its receptor are expressed in a number of cancers and cancer cell lines and may play a role in processes associated with cancer progression, including cell proliferation, apoptosis, and cell invasion and migration.


Assuntos
Grelina/metabolismo , Neoplasias/metabolismo , Animais , Comunicação Autócrina , Humanos , Modelos Biológicos , Neoplasias/patologia , Comunicação Parácrina
15.
Mol Cell Endocrinol ; 340(1): 3-9, 2011 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-21616122

RESUMO

The ghrelin axis consists of the gene products of the ghrelin gene (GHRL), and their receptors, including the classical ghrelin receptor GHSR. While it is well-known that the ghrelin gene encodes the 28 amino acid ghrelin peptide hormone, it is now also clear that the locus encodes a range of other bioactive molecules, including novel peptides and non-coding RNAs. For many of these molecules, the physiological functions and cognate receptor(s) remain to be determined. Emerging research techniques, including proteogenomics, are likely to reveal further ghrelin axis-derived molecules. Studies of the role of ghrelin axis genes, peptides and receptors, therefore, promises to be a fruitful area of basic and clinical research in years to come.


Assuntos
Grelina/genética , Grelina/metabolismo , Receptores de Grelina/metabolismo , Aciltransferases/metabolismo , Animais , Grelina/química , Humanos , Modelos Biológicos
16.
Mol Cell Endocrinol ; 340(1): 111-7, 2011 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-21459124

RESUMO

Obestatin is a 23 amino acid, ghrelin gene-derived peptide hormone produced in the stomach and a range of other tissues throughout the body. While it was initially reported that obestatin opposed the actions of ghrelin with regards to appetite and food intake, it is now clear that obestatin is not an endogenous ghrelin antagonist, but it is a multi-functional peptide hormone in its own right. In this review we will discuss the controversies associated with the discovery of obestatin and explore emerging central and peripheral roles of obestatin, which includes adipogenesis, pancreatic homeostasis and cancer.


Assuntos
Doença , Grelina/genética , Saúde , Animais , Grelina/química , Grelina/metabolismo , Humanos , Modelos Biológicos
17.
Int J Parasitol ; 40(4): 499-507, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19909754

RESUMO

The cattle tick, Rhipicephalus (Boophilus) microplus, and the diseases it transmits pose a persistent threat to tropical beef production. Genetic selection of host resistance has become the method of choice for non-chemical control of cattle tick. Previous studies have suggested that larval stages are most susceptible to host resistance mechanisms. To gain insights into the molecular basis of host resistance that occurs during R. microplus attachment, we assessed the abundance of proteins (by isobaric tag for relative and absolute quantitation (iTRAQ) and Western blot analyses) and mRNAs (by quantitative reverse transcription PCR (qRT-PCR)) in skin adjacent to tick bite sites from high tick-resistant (HR) and low tick-resistant (LR) Belmont Red cattle following challenge with cattle tick. We showed substantially higher expression of the basal epidermal keratins KRT5 and KRT14, the lipid processing protein, lipocalin 9 (LCN9), the epidermal barrier catalysing enzyme transglutaminase 1 (TGM1), and the transcriptional regulator B lymphocyte-induced maturation protein 1 (Blimp1) in HR skin. Our data reveals the essential role of the epidermal permeability barrier in conferring greater resistance of cattle to tick infestation, and suggest that the physical structure of the epidermal layers of the skin may represent the first line of defence against ectoparasite invasion.


Assuntos
Doenças dos Bovinos/imunologia , Doenças dos Bovinos/parasitologia , Ectoparasitoses/veterinária , Imunidade Inata , Rhipicephalus/imunologia , Animais , Western Blotting , Bovinos , Perfilação da Expressão Gênica , Proteoma/análise , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Pele/química , Pele/parasitologia
18.
J Insect Physiol ; 56(2): 212-26, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19840806

RESUMO

The continued development of effective anti-tick vaccines remains the most promising prospect for the control of the cattle tick, Rhipicephalus (Boophilus) microplus. A vaccine based on midgut proteins could interfere with successful tick feeding and additionally interfere with midgut developmental stages of Babesia parasites, providing opportunities for the control of both the tick and the pathogens it transmits. Midgut proteins from partially fed adult female cattle ticks were analysed using a combination of 2-DE and gel-free LC-MS/MS. Analysis of the urea-soluble protein fraction resulted in the confident identification of 105 gut proteins, while the PBS-soluble fraction yielded an additional 37 R. microplus proteins. The results show an abundance of proteins involved in mitochondrial ATP synthesis, electron transport chain, protein synthesis, chaperone, antioxidant and protein folding and transport activities in midgut tissues of adult female ticks. Among the novel products identified were clathrin-adaptor protein, which is involved in the assembly of clathrin-coated vesicles, and membrane-associated trafficking proteins such as syntaxin 6 and surfeit 4. The observations allow the formulation of hypotheses regarding midgut physiology and will serve as a basis for future vaccine development and tick-host interaction research.


Assuntos
Proteoma/metabolismo , Rhipicephalus/química , Rhipicephalus/metabolismo , Animais , Sistema Digestório/química , Sistema Digestório/imunologia , Sistema Digestório/metabolismo , Eletroforese em Gel Bidimensional , Feminino , Dados de Sequência Molecular , Proteínas/química , Proteínas/genética , Proteínas/imunologia , Proteínas/metabolismo , Proteoma/química , Proteoma/genética , Proteoma/imunologia , Rhipicephalus/genética , Rhipicephalus/imunologia
19.
Proteomics ; 8(14): 2967-82, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18655072

RESUMO

Proteomic analysis of bovine conceptus fluid proteins during early pregnancy has the potential to expose protein species indicative of both the overall health of the fetal-maternal environment and fetal developmental status. In this study, we examined the differential abundance of bovine conceptus fluid proteins (5-50 kDa fraction) from naturally conceived, in vitro fertilisation (IVF) and somatic cell nuclear transfer (SCNT)-derived pregnancies at days 45 and 90 of gestation. In day 45 allantoic fluid (AllF) samples, an atypical cluster of low molecular weight ( approximately 14-16 kDa), low pI (between 3.0 and 4.5 pH units) protein species was increased in three of four IVF samples (30-100-fold increase in protein spot volumes compared to normal). These proteins were identified as paralogs of the bovine cathelicidin antimicrobial protein (CAMP) by MALDI-TOF MS peptide mass fingerprint and MALDI-TOF MS/MS peptide sequence analysis. Peptidoglycan recognition protein and serine (or cysteine) proteinase inhibitor clade B1, were also significantly increased in the corresponding IVF samples. In two of four SCNT AllF samples, a 2-10-fold increase in CAMP protein spot volumes were detected. No aberrant abundance levels of individual protein species were observed in amniotic fluid samples, or in day 90 IVF AllF samples. Identification of unique protein species present in the normal bovine AllF proteome at day 45 is also reported.


Assuntos
Líquido Amniótico/metabolismo , Proteoma/metabolismo , Proteômica , Técnicas de Reprodução Assistida , Alantoide/química , Alantoide/metabolismo , Sequência de Aminoácidos , Líquido Amniótico/química , Animais , Peptídeos Catiônicos Antimicrobianos/análise , Peptídeos Catiônicos Antimicrobianos/metabolismo , Proteínas de Transporte/análise , Proteínas de Transporte/metabolismo , Catelicidinas , Bovinos , Eletroforese em Gel Bidimensional , Feminino , Dados de Sequência Molecular , Técnicas de Transferência Nuclear , Gravidez , Proteoma/análise , Inibidores de Serina Proteinase/análise , Inibidores de Serina Proteinase/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
20.
FEMS Microbiol Lett ; 278(1): 115-20, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18028391

RESUMO

A new DNA sequence cry5Ad/orf2-5Ad (GenBank accession number EF219060) was isolated from Bacillus thuringiensis strain L366. This DNA sequence contains two ORFs: cry5Ad (a previously unreported member of the cry5A gene family) and orf2-5Ad. cry5Ad is unique among cry5A genes in that it encodes only the N-terminal region of a typical Cry5Adelta-endotoxin. The cry5Ad sequence includes homology blocks 1-5, which are present in most B. thuringiensisdelta-endotoxins. The usual C-terminal region of a Cry5Adelta-endotoxin (including homology blocks 6-8) is encoded by orf2-5Ad. Both proteins encoded by cry5Ad and orf2-5Ad were found in IPTG-induced Escherichia coli, after a copy of cry5Ad/orf2-5Ad was cloned into the pQE32 expression vector and transformed into pREP4 E. coli cells. Both proteins were also found in parasporal crystal inclusions of B. thuringiensis L366. Sequencing of cDNA derived from transformed E. coli cells showed that the two ORFs are transcribed as a single mRNA. Extracts prepared from the recombinant E. coli expressing Cry5Ad and Orf2-5Ad were not toxic to nematode larvae (Haemonchus contortus), indicating that these two proteins are most likely not responsible for the nematocidal activity seen previously in the B. thuringiensis strain L366.


Assuntos
Antinematódeos , Bacillus thuringiensis/genética , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Clonagem Molecular , Endotoxinas/genética , Proteínas Hemolisinas/genética , Motivos de Aminoácidos , Animais , Antinematódeos/química , Antinematódeos/toxicidade , Bacillus thuringiensis/química , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/química , Proteínas de Bactérias/toxicidade , Toxinas Bacterianas/química , Toxinas Bacterianas/toxicidade , Endotoxinas/química , Endotoxinas/toxicidade , Escherichia coli/genética , Haemonchus/efeitos dos fármacos , Haemonchus/crescimento & desenvolvimento , Proteínas Hemolisinas/química , Proteínas Hemolisinas/toxicidade , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Dados de Sequência Molecular , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/toxicidade , Mapeamento por Restrição
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