RESUMO
Freshwater snails of the genus Biomphalaria serve as intermediate hosts for the digenetic trematode Schistosoma mansoni, the etiological agent for the most widespread form of intestinal schistosomiasis. As neuropeptide signaling in host snails can be altered by trematode infection, a neural transcriptomics approach was undertaken to identify peptide precursors in Biomphalaria glabrata, the major intermediate host for S. mansoni in the Western Hemisphere. Three transcripts that encode peptides belonging to the FMRF-NH2 -related peptide (FaRP) family were identified in B. glabrata. One transcript encoded a precursor polypeptide (Bgl-FaRP1; 292 amino acids) that included eight copies of the tetrapeptide FMRF-NH2 and single copies of FIRF-NH2 , FLRF-NH2 , and pQFYRI-NH2 . The second transcript encoded a precursor (Bgl-FaRP2; 347 amino acids) that comprised 14 copies of the heptapeptide GDPFLRF-NH2 and 1 copy of SKPYMRF-NH2 . The precursor encoded by the third transcript (Bgl-FaRP3; 287 amino acids) recapitulated Bgl-FaRP2 but lacked the full SKPYMRF-NH2 peptide. The three precursors shared a common signal peptide, suggesting a genomic organization described previously in gastropods. Immunohistochemical studies were performed on the nervous systems of B. glabrata and B. alexandrina, a major intermediate host for S. mansoni in Egypt. FMRF-NH2 -like immunoreactive (FMRF-NH2 -li) neurons were located in regions of the central nervous system associated with reproduction, feeding, and cardiorespiration. Antisera raised against non-FMRF-NH2 peptides present in the tetrapeptide and heptapeptide precursors labeled independent subsets of the FMRF-NH2 -li neurons. This study supports the participation of FMRF-NH2 -related neuropeptides in the regulation of vital physiological and behavioral systems that are altered by parasitism in Biomphalaria.
Assuntos
FMRFamida/genética , Neuropeptídeos/genética , Esquistossomose mansoni/genética , Transcriptoma/genética , Sequência de Aminoácidos , Animais , Biomphalaria , FMRFamida/análise , FMRFamida/metabolismo , Neuropeptídeos/análise , Neuropeptídeos/metabolismo , Imagem Óptica/métodos , Schistosoma mansoni/genética , Schistosoma mansoni/isolamento & purificação , Esquistossomose mansoni/metabolismoRESUMO
This study describes the histological characteristics and distribution of gastrointestinal tract endocrine cells (ECs) of Prochilodus lineatus (detritivorous fish) using immunohistochemical procedures. The digestive tract of P. lineatus was divided into seven portions: stomach (cardial and pyloric), pyloric caeca, and intestine (anterior, glandular, middle and posterior). A pool of specific antisera against cholecystokinin (CCK-8), -neuropeptide Y (NPY), -ghrelin (Ghre) and -leu-enkephalin (Leu-ENK) to identify ECs were used. According to the morphological characteristics of ECs, two different types were identified and classified as open or closed-type. The number of ECs varied throughout the gastrointestinal tract, though a high abundance was found in the anterior intestine and pyloric caeca. A large number of ECs immunoreactive to CCK-8 and NPY were recorded in the anterior, glandular and middle intestine. ECs immunopositive to Leu-ENK were distributed in the stomach and pyloric caeca. For Ghre, immunopositive ECs were restricted to the glandular intestine. The results of the present study indicate that P. lineatus presents an ECs distribution pattern with species-specific particularities. However, CCK showed a distribution similar to that of omnivores, which is possibly related to local signaling functions in order to achieve the correct digestion of the various organisms found in the detritus.
Assuntos
Caraciformes/classificação , Encefalina Leucina/análise , Trato Gastrointestinal/química , Grelina/análise , Neuropeptídeos/análise , Sincalida/análise , Animais , Imuno-HistoquímicaRESUMO
INTRODUCTION: Despite clinical characteristics and complementary exams indicate acute appendicitis, 15% to 40% of all appendectomies result in removal of appendices with normal macro- and micromorphological aspects. Even so, manifestations of acute abdomen disappear immediately after the appendectomy, and never show back again. OBJECTIVE: To assess changes of neuroimmunoendocrine peptides on removed appendices due to clinical presentation of acute appendicitis. METHOD: This article presents an updated revision of acute appendicitis, based on references found on PUBMED, LILACS, MEDLINE, WHOLIS and SciELO, using key words "acute appendicitis", "neuroimmune appendicitis", "neurogenic appendicopathy", and "incidental appendectomy". RESULTS: Fourteen neuropeptides were analyzed by different authors who suggested the presence of neurogenic appendicopathy in morphologically normal appendices removed from patients with clinical presentation suggesting acute appendicitis. CONCLUSION: The etiopathogeny of acute appendicitis continues to be unknown, and there is a great possibility that patients with morphologically normal appendices with clinical presentation of acute appendicitis that heal after appendectomy present a neuroimmunoendocrine disease.
Assuntos
Apendicectomia , Apendicite/patologia , Apêndice/patologia , Neuropeptídeos/análise , Doença Aguda , Adolescente , Adulto , Apendicite/cirurgia , Feminino , Humanos , Masculino , Período Pós-Operatório , Período Pré-Operatório , Adulto JovemRESUMO
Aggressiveness in honeybees seems to be regulated by multiple genes, under the influence of different factors, such as polyethism of workers, environmental factors, and response to alarm pheromones, creating a series of behavioral responses. It is suspected that neuropeptides seem to be involved with the regulation of the aggressive behavior. The role of allatostatin and tachykinin-related neuropeptides in honeybee brain during the aggressive behavior is unknown, and thus worker honeybees were stimulated to attack and to sting leather targets hung in front of the colonies. The aggressive individuals were collected and immediately frozen in liquid nitrogen; the heads were removed and sliced at sagittal plan. The brain slices were submitted to MALDI spectral imaging analysis, and the results of the present study reported the processing of the precursors proteins into mature forms of the neuropeptides AmAST A (59-76) (AYTYVSEYKRLPVYNFGL-NH2), AmAST A (69-76) (LPVYNFGL-NH2), AmTRP (88-96) (APMGFQGMR-NH2), and AmTRP (254-262) (ARMGFHGMR-NH2), which apparently acted in different neuropils of the honeybee brain during the aggressive behavior, possibly taking part in the neuromodulation of different aspects of this complex behavior. These results were biologically validated by performing aggressiveness-related behavioral assays using young honeybee workers that received 1 ng of AmAST A (69-76) or AmTRP (88-96) via hemocele. The young workers that were not expected to be aggressive individuals presented a complete series of aggressive behaviors in the presence of the neuropeptides, corroborating the hypothesis that correlates the presence of mature AmASTs A and AmTRPs in the honeybee brain with the aggressiveness of this insect.
Assuntos
Abelhas/química , Química Encefálica/efeitos dos fármacos , Encéfalo/diagnóstico por imagem , Neuropeptídeos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Agressão/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Proteínas de Insetos , Neuropeptídeos/farmacologia , Neuropeptídeos/fisiologia , Neurópilo , Feromônios/metabolismo , Feromônios/farmacologia , Taquicininas/farmacologiaRESUMO
The endocannabinoid system, composed of cannabinoid receptors, endocannabinoids, and synthesis and degradation enzymes, is present since early stages of brain development. During this period, the endocannabinoid system is involved in the regulation of neural progenitor proliferation and specification as well as the migration and differentiation of pyramidal neurons and interneurons. Marijuana consumption during pregnancy represents a serious risk in relation to the fetal brain development since Δ(9) -tetrahidrocannabinol, the main active compound of cannabis, can reach the fetus through placenta and hemato-encephalic barrier. Cohort studies performed on children and adolescents of mothers who consumed marijuana during pregnancy reported cognitive and comportamental abnormalities. In the present study, we examined the expression of the cannabinoid receptor CB1 R during corticogenesis in radially and tangentially migrating post-mitotic neurons. We found that prenatal exposure to WIN impaired tangential and radial migration of post-mitotic neurons in the dorsal pallium. In addition, we described alterations of two transcription factors associated with proliferating and newly post-mitotic glutamatergic cells in the dorsal pallium, Tbr1 and Tbr2, and disruption in the number of Cajal-Retzius cells. The present results contribute to the knowledge of neurobiological substrates that determine neuro-comportamental changes that will persist through post-natal life.
Assuntos
Benzoxazinas/farmacologia , Agonistas de Receptores de Canabinoides/farmacologia , Córtex Cerebral/citologia , Endocanabinoides/fisiologia , Morfolinas/farmacologia , Naftalenos/farmacologia , Neurônios/efeitos dos fármacos , Receptor CB1 de Canabinoide/fisiologia , Animais , Apoptose/efeitos dos fármacos , Moléculas de Adesão Celular Neuronais/análise , Divisão Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/embriologia , Proteínas do Domínio Duplacortina , Proteínas da Matriz Extracelular/análise , Feminino , Neurônios GABAérgicos/citologia , Neurônios GABAérgicos/efeitos dos fármacos , Neurônios GABAérgicos/fisiologia , Ácido Glutâmico/fisiologia , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/embriologia , Interneurônios/citologia , Interneurônios/efeitos dos fármacos , Interneurônios/fisiologia , Proteínas Associadas aos Microtúbulos/análise , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/metabolismo , Neurogênese/efeitos dos fármacos , Neurônios/citologia , Neurônios/fisiologia , Neuropeptídeos/análise , Gravidez , Ratos , Ratos Wistar , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/biossíntese , Proteína Reelina , Serina Endopeptidases/análise , Proteínas com Domínio T/metabolismo , Transcrição GênicaRESUMO
Neurogenesis in the subgranular layer of the dentate gyrus (DG) has been suggested to underlie some forms of associative learning. The present study was undertaken to determine whether there was also a role of neurogenesis in the ethanol (EtOH)-induced conditioned place preference (CPP). Outbreed Swiss mice were conditioned with EtOH (2.0 g/kg) in one compartment of a non-biased place preference chamber and saline in the other compartment. This procedure produced three groups of mice: some developed a conditioned preference (EtOH_Cpp), others developed a conditioned avoidance (EtOH_Cpa) and still others demonstrated indifference to the context previously paired with ethanol (EtOH_Ind). BrdU (40 mg/kg, i.p.) was administered 4 hours after each session comprising the conditioning phase. When measured 24 hours following the CPP test, there was no effect of EtOH on doublecortin (DCX) expression or Fluoro Jade B staining. However, there were decreases in the number of BrdU+ and Ki-67+ cells in the EtOH_Cpa and EtOH_Ind groups, but not in the EtOH_Cpp group. Most of BrdU+ cells were co-labeled with DCX. Similarly, in another experiment, in that the perfusion was done 28 days after CPP test, most BrdU+ cells were co-localized with NeuN. These results suggest that conditioned appetitive response is able to maintain normal levels of neurogenesis in DG and might counteract ethanol-produced decreased cell proliferation/survival rate.
Assuntos
Comportamento Apetitivo/fisiologia , Proliferação de Células/efeitos dos fármacos , Etanol/farmacologia , Hipocampo/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Análise de Variância , Animais , Animais não Endogâmicos , Aprendizagem por Associação/efeitos dos fármacos , Aprendizagem por Associação/fisiologia , Aprendizagem da Esquiva/efeitos dos fármacos , Comportamento Aditivo/psicologia , Bromodesoxiuridina/administração & dosagem , Contagem de Células , Morte Celular/efeitos dos fármacos , Condicionamento Psicológico/efeitos dos fármacos , Proteínas de Ligação a DNA , Giro Denteado/citologia , Giro Denteado/efeitos dos fármacos , Giro Denteado/metabolismo , Proteínas do Domínio Duplacortina , Proteína Duplacortina , Etanol/administração & dosagem , Fluoresceínas , Hipocampo/citologia , Hipocampo/metabolismo , Abrigo para Animais , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Masculino , Camundongos , Proteínas Associadas aos Microtúbulos/análise , Proteínas do Tecido Nervoso/metabolismo , Neuropeptídeos/análise , Proteínas Nucleares/metabolismo , Fenótipo , Reforço Psicológico , Coloração e RotulagemRESUMO
Doublecortin (DCX) is a microtubule-associated protein essential for the migration of immature neurons in the developing and adult vertebrate brain. Herein, the distribution of DCX-immunoreactive (DCX-ir) cells in the prosencephalon of the adult pigeon (Columba livia) is described, in order to collect the evidence of their immature neural phenotype and to investigate their putative place of origin. Bipolar and multipolar DCX-ir cells were observed to be widespread throughout the parenchyma of the adult pigeon forebrain. Small, bipolar and fusiform DCX-ir cells were especially concentrated at the tips of the lateral walls of the lateral ventricles (VZ) and sparsely distributed in the remaining ependyma. Multipolar DCX-ir cells populated the pallial regions. None of these DCX-ir cells seemed to co-express NeuN or GFAP, suggesting that they were immature neurons. Two different migratory-like routes of DCX-ir cells from the VZ toward different targets in the parenchyma were putatively identified: (i) rostral migratory-like bundle; and (ii) lateral migratory-like bundle. In addition, pial surface bundles and intra-ependymal fascicles were also observed. Pigeons treated with 5-bromo-desoxyuridine (BrdU, 3 intraperitoneal injections of 100mg/kg 2h apart, sacrificed 2h after last injection) displayed BrdU-immunoreactive cells (BrdU-ir) in VZ and ependyma whereas the parenchyma was free of such cells. Despite the regional overlapping, there was no evidence of double-labeling between BrdU and DCX. Therefore, the VZ in the brain of adult pigeons seems to have rapidly dividing cells as putative progenitors of newborn neurons populating the forebrain. The distribution of the newborn neurons in the avian prosencephalon and their migration pathways appear to be larger than in mammals, suggesting that the morphological turnover of forebrain circuits is an important mechanism for brain plasticity in avian species during adulthood.
Assuntos
Encéfalo/metabolismo , Columbidae/metabolismo , Proteínas Associadas aos Microtúbulos/biossíntese , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neuropeptídeos/biossíntese , Animais , Encéfalo/citologia , Diferenciação Celular/fisiologia , Movimento Celular/fisiologia , Columbidae/anatomia & histologia , Proteínas do Domínio Duplacortina , Feminino , Imuno-Histoquímica , Masculino , Proteínas Associadas aos Microtúbulos/análise , Neurogênese/fisiologia , Neuropeptídeos/análiseRESUMO
Phoneutria nigriventer spider bite causes priapism, an effect attributed to the peptide toxins Tx2-5 and Tx2-6 and involving nitric oxide. Tx2-6 (MW = 5287) is known to delay the inactivation of Sodium channels in the same fashion as many other venom toxins. In the present study we evaluated the i.p. dose that induces priapism and the other symptoms in mice. Animals killed by the toxin or crude venom (0.85 mg/kg) were autopsied and a pathological study of brain, lung, kidney, liver and heart was undertaken using standard techniques. The same protocol was employed with animals injected with crude venom. Results showed that priapism is the first sign of intoxication, followed by piloerection, abundant salivation and tremors. An i.p. injection of about 0.3 µg/kg induced only priapism with minimal side-effects. The most remarkable histological finding was a general vascular congestion in all organs studied. Penis showed no necrosis or damage. Lungs showed vascular congestion and alveolar hemorrhage. Heart showed also sub-endothelial hemorrhage. Brain showed only a mild edema and vascular congestion. Results obtained with crude venom closely resemble those of purified toxin. We conclude that Tx2-6 have profound effects on the vascular bed especially in lungs and heart, which may be the cause of death. Interestingly brain tissue was less affected and the observed edema may be attributed to respiratory impairment. To the best of our knowledge this is the first histopathological investigation on this toxin and venom suggesting a possible cause of death.
Assuntos
Neuropeptídeos/intoxicação , Neurotoxinas/intoxicação , Priapismo/induzido quimicamente , Picada de Aranha/patologia , Venenos de Aranha/química , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Coração/efeitos dos fármacos , Técnicas Histológicas , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Camundongos , Neuropeptídeos/análise , Neurotoxinas/análise , Priapismo/patologia , Picada de Aranha/mortalidadeRESUMO
The inner surface of fused silica capillaries has been covalently modified with different porphyrins (deuteroporphyrin, complexes of deuteroporphyrin with metal ions Fe(III), Cu(II), Zn(II), Ni(II), and Cu(II)-meso-tetra (carboxyphenyl) porphyrin) and it was applied for the separation of biologically active peptides by open-tubular capillary electrochromatography. Separations were performed in a mobile phase composed of 25 mM potassium phosphate, pH 4.0, 5% v/v ACN and 10 mM hydroquinone. Changes in the effective electrophoretic mobility of peptides were studied concerning porphyrin central metal atom, attachment geometry, and the presence of coordinating or aromatic amino acid residues in the peptide sequence. The results showed that differences in metal core on the porphyrin and the spatial conformation of attached porphyrin result in changes in the analyte interaction with the stationary phase.
Assuntos
Eletrocromatografia Capilar/instrumentação , Deuteroporfirinas/química , Mesoporfirinas/química , Metais Pesados/química , Neuropeptídeos/análise , Eletrocromatografia Capilar/métodos , Modelos Moleculares , Neuropeptídeos/química , Estatísticas não ParamétricasRESUMO
We show a straightforward workflow combining homology search in Rhodnius prolixus genome sequence with cloning by rapid amplification of cDNA ends and mass spectrometry. We have identified 32 genes and their transcripts that encode a number of neuropeptide precursors leading to 194 putative peptides. We validated by mass spectrometry 82 of those predicted neuropeptides in the brain of R. prolixus to achieve the first comprehensive genomic, transcriptomic and neuropeptidomic analysis of an insect disease vector. Comparisons of available insect neuropeptide sequences revealed that the R. prolixus genome contains most of the conserved neuropeptides in insects, many of them displaying specific features at the sequence level. Some gene families reported here are identified for the first time in the order Hemiptera, a highly biodiverse group of insects that includes many human, animal and plant disease agents.