RESUMO
Ophiactis savignyi could be discovered all over the world in tropical marine environments. People could have aided in the spread of O. savignyi, particularly in the western and eastern populations of Panama's Isthmus. The brittle star Ophiactis savignyi, often known as savigny's brittle star, coexists alongside the sponge Geodia corticostylifera. The focus of this research has been to assess the functional relevance of G. corticostylifera secondary metabolites as antifoulant against mussels, protection against generalist fish, and chemical cues to affiliated brittle stars. Both in flow-through and static seawater laboratory studies, O. savignyi which has previously been connected with sponges, was given both treated and control mimics at the same time. The sponge extract was also tested for its ability to protect fish against predators and fouling. Deterrence test using chemicals indicated that the normal level of the sponge extract may also suppress generalist fish predation in the field as well as the mussel Perna perna's normal attachment in clinical contexts. According to the findings, G. corticostylifera crude extract has many roles in the aquatic environments, apparently being accountable for this sponge's tighter relationship with O. savignyi, which protects the ophiuroid and inhibits epibionts on itself.
Ophiactis savignyi pode ser descoberta em todo o mundo em ambientes marinhos tropicais. A população pode ter contribuído para a propagação de O. savignyi, particularmente as populações ocidentais e orientais do istmo do Panamá. A estrela-quebradiça O. savignyi, muitas vezes conhecida como estrela-quebradiça de Savignyi, coexiste com a esponja Geodia corticostylifera. O foco desta pesquisa foi avaliar a relevância funcional dos metabólitos secundários de G. corticostylifera como anti-incrustante contra mexilhões, proteção contra peixes generalistas e sinais químicos para estrelas-quebradiças afiliadas. Em estudos de laboratório com fluxo contínuo e estático de água do mar, O. savignyi, que anteriormente havia se ligado a esponjas, recebeu mimetizadores tratados e controle ao mesmo tempo. O extrato de esponja também foi testado por sua capacidade de proteger os peixes contra predadores e incrustações. Testes de dissuasão usando produtos químicos indicaram que o nível normal de extrato de esponja também pode suprimir a predação de peixes generalistas no campo, bem como a fixação normal do mexilhão Perna perna em ambientes clínicos. De acordo com os achados, o extrato bruto de G. corticostylifera tem diversas funções em ambientes aquáticos, aparentemente responsáveis pela relação mais próxima dessa esponja com O. savignyi, protegendo o ofiuroide e inibindo os epibiontes.
Assuntos
Animais , Poríferos/parasitologia , Simbiose , Bactérias , Geodia/parasitologiaRESUMO
Ophiactis savignyi could be discovered all over the world in tropical marine environments. People could have aided in the spread of O. savignyi, particularly in the western and eastern populations of Panama's Isthmus. The brittle star Ophiactis savignyi, often known as savigny's brittle star, coexists alongside the sponge Geodia corticostylifera. The focus of this research has been to assess the functional relevance of G. corticostylifera secondary metabolites as antifoulant against mussels, protection against generalist fish, and chemical cues to affiliated brittle stars. Both in flow-through and static seawater laboratory studies, O. savignyi which has previously been connected with sponges, was given both treated and control mimics at the same time. The sponge extract was also tested for its ability to protect fish against predators and fouling. Deterrence test using chemicals indicated that the normal level of the sponge extract may also suppress generalist fish predation in the field as well as the mussel Perna perna's normal attachment in clinical contexts. According to the findings, G. corticostylifera crude extract has many roles in the aquatic environments, apparently being accountable for this sponge's tighter relationship with O. savignyi, which protects the ophiuroid and inhibits epibionts on itself.
Assuntos
Geodia , Animais , Peixes , Humanos , Comportamento PredatórioRESUMO
In this contribution we revise the type specimens of Geodia tylastra, Rhabdastrella fibrosa and Geodia corticostylifera, adding new photographs of preserved specimens, skeleton sections, and scanning electron micrographs of the spicules. We demonstrate that the three species are synonyms, with priority to the older name G. tylastra Boury-Esnault, 1973. We also show that Rhabdastrella fibrosa sensu Van Soest (2017) differs from the holotype in spicule composition and is here given a new name, Rhabdastrella vansoesti sp. nov. In addition, we describe a new species of Geodia, G. polytriaena sp. nov., and new records of G. glariosa and G. tylastra from Sergipe State, in the Northeast Brazilian coast. With the description of Geodia polytriaena sp. nov. and the synonymyzation of G. corticostylifera, 20 species of Geodia are now known in the Tropical Western Atlantic Ocean.
Assuntos
Geodia , Poríferos , Animais , Brasil , MicroscopiaRESUMO
We are investigating effects of the depsipeptide geodiamolide H, isolated from the Brazilian sponge Geodia corticostylifera, on cancer cell lines grown in 3D environment. As shown previously geodiamolide H disrupts actin cytoskeleton in both sea urchin eggs and breast cancer cell monolayers. We used a normal mammary epithelial cell line MCF 10A that in 3D assay results formation of polarized spheroids. We also used cell lines derived from breast tumors with different degrees of differentiation: MCF7 positive for estrogen receptor and the Hs578T, negative for hormone receptors. Cells were placed on top of Matrigel. Spheroids obtained from these cultures were treated with geodiamolide H. Control and treated samples were analyzed by light and confocal microscopy. Geodiamolide H dramatically affected the poorly differentiated and aggressive Hs578T cell line. The peptide reverted Hs578T malignant phenotype to polarized spheroid-like structures. MCF7 cells treated by geodiamolide H exhibited polarization compared to controls. Geodiamolide H induced striking phenotypic modifications in Hs578T cell line and disruption of actin cytoskeleton. We investigated effects of geodiamolide H on migration and invasion of Hs578T cells. Time-lapse microscopy showed that the peptide inhibited migration of these cells in a dose-dependent manner. Furthermore invasion assays revealed that geodiamolide H induced a 30% decrease on invasive behavior of Hs578T cells. Our results suggest that geodiamolide H inhibits migration and invasion of Hs578T cells probably through modifications in actin cytoskeleton. The fact that normal cell lines were not affected by treatment with geodiamolide H stimulates new studies towards therapeutic use for this peptide.
Assuntos
Neoplasias da Mama/patologia , Técnicas de Cultura de Células , Movimento Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Depsipeptídeos/farmacologia , Invasividade Neoplásica , Células Tumorais Cultivadas/efeitos dos fármacos , Actinas/metabolismo , Animais , Apoptose , Materiais Biocompatíveis/metabolismo , Linhagem Celular , Polaridade Celular , Forma Celular , Colágeno/metabolismo , Citocalasina D/farmacologia , Combinação de Medicamentos , Feminino , Geodia , Humanos , Laminina/metabolismo , Inibidores da Síntese de Ácido Nucleico/farmacologia , Proteoglicanas/metabolismoRESUMO
Crude extracts of the marine sponge Geodia corticostylifera from Brazilian Coast have previously shown antibacterial, antifungal, cytotoxic, haemolytic and neurotoxic activities. The present work describes the isolation of the cyclic peptides geodiamolides A, B, H and I (1-4) from G. corticostylifera and their anti-proliferative effects against sea urchin eggs and human breast cancer cell lineages. Its structure-activity relationship is discussed as well. In an initial series of experiments these peptides inhibited the first cleavage of sea urchin eggs (Lytechinus variegatus). Duplication of nuclei without complete egg cell division indicated the mechanism of action might be related to microfilament disruption. Further studies showed that the geodiamolides have anti-proliferative activity against human breast cancer cell lines (T47D and MCF7). Using fluorescence techniques and confocal microscopy, we found evidence that the geodiamolides A, B, H and I act by disorganizing actin filaments of T47D and MCF7 cancer cells, in a way similar to other depsipeptides (such as jaspamide 5 and dolastatins), keeping the normal microtubule organization. Normal cells lines (primary culture human fibroblasts and BRL3A rat liver epithelial cells) were not affected by the treatment as tumor cells were, thus indicating the biomedical potential of these compounds.
Assuntos
Antineoplásicos/farmacologia , Citoesqueleto/efeitos dos fármacos , Depsipeptídeos/farmacologia , Geodia , Animais , Antineoplásicos/química , Neoplasias da Mama/ultraestrutura , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Citoesqueleto/metabolismo , Citoesqueleto/ultraestrutura , Depsipeptídeos/química , Depsipeptídeos/isolamento & purificação , Relação Dose-Resposta a Droga , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Imunofluorescência , Geodia/metabolismo , Humanos , Microscopia Confocal , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Ratos , Relação Estrutura-Atividade , Células Tumorais CultivadasRESUMO
Crude extracts of the marine sponge Geodia corticostylifera from Brazilian Coast have previously shown antibacterial, antifungal, cytotoxic, haemolytic and neurotoxic activities. The present work describes the isolation of the cyclic peptides geodiamolides A, B, H and I (14) from G. corticostylifera and their anti-proliferative effects against sea urchin eggs and human breast cancer cell lineages. Its structureactivity relationship is discussed as well. In an initial series of experiments these peptides inhibited the first cleavage of sea urchin eggs (Lytechinus variegatus). Duplication of nuclei without complete egg cell division indicated the mechanism of action might be related to microfilament disruption. Further studies showed that the geodiamolides have anti-proliferative activity against human breast cancer cell lines (T47D and MCF7). Using fluorescence techniques and confocal microscopy, we found evidence that the geodiamolides A, B, H and I act by disorganizing actin filaments of T47D and MCF7 cancer cells, in a way similar to other depsipeptides (such as jaspamide 5 and dolastatins), keeping the normal microtubule organization. Normal cells lines (primary culture human fibroblasts and BRL3A rat liver epithelial cells) were not affected by the treatment as tumor cells were, thus indicating the biomedical potential of these compounds.
Assuntos
Humanos , Citoesqueleto , Geodia/classificação , Neoplasias da Mama , DepsipeptídeosRESUMO
In our search for marine bioactive compounds we chose a Brazilian Coast sponge, Geodia corticostylifera (Demospongiae), whose extracts showed previously antibacterial and antifungal activities. In the present work we studied the following toxic properties of G. corticostylifera extract: neurotoxic (in mouse neuromuscular junction); mouse acute toxicity (IP) and haemolytic (against mouse and frog erythrocytes). Insertion of ionic channels in planar lipid bilayers in presence of a haemolytic purified fraction of the extract was observed. The toxic activities of G. corticostylifera crude extract are related to the formation of ionic pores in the cell membrane, which induce the release of haemoglobin from erythrocytes, and depolarization of nerve and muscle membranes. These last physiological effects cause the blockade of the diaphragm contractions, leading to death through respiratory arrest.
Assuntos
Geodia/patogenicidade , Hemólise/efeitos dos fármacos , Neurotoxinas/toxicidade , Animais , Membrana Celular/efeitos dos fármacos , Dose Letal Mediana , Bicamadas Lipídicas , Masculino , Camundongos , Junção Neuromuscular/efeitos dos fármacos , Junção Neuromuscular/fisiologia , RanidaeRESUMO
In our search for marine bioactive compounds we chose a Brazilian Coast sponge, Geodia corticostylifera (Demospongiae), whose extracts showed previously antibacterial and antifungal activities. In the present work we studied the following toxic properties of G. corticostylifera extract: neurotoxic (in mouse neuromuscular junction); mouse acute toxicity (IP) and haemolytic (against mouse and frog erythrocytes). Insertion of ionic channels in planar lipid bilayers in presence of a haemolytic purified fraction of the extract was observed. The toxic activities of G. corticostylifera crude extract are related to the formation of ionic pores in the cell membrane, which induce the release of haemoglobin from erythrocytes, and depolarization of nerve and muscle membranes. These last physiological effects cause the blockade of the diaphragm contractions, leading to death through respiratory arrest.