Browsing by Subject "Teleosts"
Now showing 1 - 14 of 14
Results Per Page
Sort Options
- PublicationRestrictedCharacterization of macrophages from the bony fish gilthead seabream using an antibody against the macrophage colony-stimulating factor receptor(Elsevier, 2008-04-07) Mulero Méndez, Iván; Meseguer Peñalver, J.; García Ayala, Alfonsa; Mulero Méndez, Victoriano Francisco; Sepulcre Cortés, María Pilar; Roca Soler, Francisco José; Bioquímica y Biología Molecular B e InmunologíaTwo major professional phagocyte populations have been described in fish, namely granulocytes and monocytes/macrophages. Although the distribution and localization of macrophages have been documented in several teleost species using mainly light and/or electron microscopy, the lack of appropriate markers for these cells has hampered our in-depth knowledge of their biology. We report here the generation of a monospecific rabbit polyclonal antibody against the gilthead seabream macrophage colony-stimulating factor receptor (Mcsfr), which is an excellent marker of macrophages in mammals and the zebrafish. The anti-Mcsfr has been found to be very useful in immunohistochemistry (IHC) to specifically immunostain the purified macrophages (adherent cells) obtained from the head-kidney as well as different cell populations in paraffin-embedded organs, including the head-kidney, spleen, thymus, gills and liver. Unexpectedly, however, no Mcsfr immunoreactive (Mcsfr+) cells were observed in the brain and intestine of the gilthead seabream. We also show that the distribution of Mcsfr+ cells in the head-kidney and the spleen is unaltered following infection with the fish pathogenic bacterium Vibrio anguillarum and that the Il1b-producing cells in these two organs after infection are exclusively acidophilic granulocytes. Finally, as the epitope recognized by the anti-Mcsfr is well conserved, we illustrate the potential usefulness of this antibody in other teleost species, such as the European seabass.
- PublicationOpen AccessChitosan-nanoparticles effects on mucosal immunity: a systematic review(Elsevier, 2022-08-26) Collado-González, Mar; Esteban Abad, María de los Ángeles; Biología Celular e HistologíaNanoparticles-based treatments is of utmost importance for aquaculture. In this scenario, chitosan-based nanoparticles have been proposed due to the properties of chitosan, which include mucoadhesiveness. Nevertheless, pivotal parameters of chitosan, such as degree of acetylation and molecular weight, are commonly underestimated in the available literature despite the influence they seem to have on the properties of chitosan-based nanoparticles. In this systematic review, the immunomodulator capacity of chitosan nanoparticles used as mucosal vaccines on teleost fish has been evaluated paying special attention to the chitosan properties. Four databases were used for literature search, yielding 486 documents, from which 14 meet the inclusion criteria. Only 21% of the available studies reported properly chitosan properties, which should be improved in future works to generate reproducible data as well as valuable information. To the best of our knowledge, this work objectively compares for the first time, by quantifying the mg of chitosan/g of fish applied in each study, the chitosan nanoparticle preparation and doses applied to fish, as well as the effects of the treatments applied on fish immune status.
- PublicationOpen AccessDescription and comparative study of physico-chemical parameters of the teleost fish skin mucus.(SAGE Publications, 2015-07-01) Guardiola Abellán, Francisco Antonio; Cuartero, María; Collado-González, Mar; Arizcún, Marta; Díaz Baños, F. Guillermo; Meseguer, José; Esteban Abad, María de los Ángeles; Biología Celular e HistologíaThe study of mucosal surfaces, and in particular the fish skin and its secreted mucus, has been of great interest recently among immunologists. Measurement of the viscosity and other physico-chemical parameters (protein concentration, pH, conductivity, redox potential, osmolality and density) of the skin mucus can help to understand its biological functions. We have used five marine species of teleost: gilthead seabream (Sparus aurata L.), European sea bass (Dicentrarchus labrax L.), shi drum (Umbrina cirrosa L.), common dentex (Dentex dentex L.) and dusky grouper (Epinephelus marginatus L.), all of them with commercial interest in the aquaculture of the Mediterranean area. Mucus showed a direct shear- and temperature-dependent viscosity, with a non-Newtonian behavior, which differed however between two groups: one with higher viscosity (D. labrax, U. cirrosa, D. dentex) and the other with lower viscosity (S. aurata, E. marginatus). In addition, there was a clear interrelation between density and osmolality, as well as between density and temperature. Taking into account that high values of viscosity should improve the barrier effect against pathogens but low values of viscosity are needed for good locomotion characteristics, our results may help elucidate the relationship between physico-chemical and biological parameters of skin mucus, and disease susceptibility.
- PublicationOpen AccessDifferent putative neuromodulators are present in the nerves which distribute to the teleost skeletal muscle(Murcia : F. Hernández, 1998) Radaelli, G.; Domeneghini, C.; Arrighi, S.; Mascarello, F.; Veggetti, A.The presence of putative neuromodulators in the nerve fibres was investigated in white skeletal muscle of two teleost fish not taxonomically correlated and showing different patterns of innervation (multiple versus focal innervation). Cryostat sections of epaxial, hypaxial and adductor mandibulae (AM) muscles of Sparus aurata and Anguilla anguilla were stained histochemically for reduced nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase. Other sections were used for indirect immunohistochemistry (streptavidin-biotin and rhodamine immunofluorescence methods), employing antibodies specific for putative excitatory or inhibitory peptides, including CGRP, substance P, met-enkephalin, bombesin, and VIP. In addition, ultrastructural observations were performed in order to describe the morphology of the motor endplates. A strong immunoreactivity for CGRP and substance P was found in many nerve terminals. Met-enkephalin, bombesin and VIP immunoreactivities were less frequently observed. No immunoreactivity was observed to CCK, NPY or 5-HT. NADPH-diaphorase was identified in nerve fibres of the AM complex only of A. anguilla. Electron microscopy observations evidenced more than one type of synaptic vesicle in motor endplates. Some differences in putative neuromodulator distributions were observed in the two species and muscle complexes, which may be related to the different taxonomical position as well as the different pattern of innervation of white muscle fibres.
- PublicationOpen AccessDiversity and dynamics of fish ovaries: Insights into reproductive strategies, hormonal regulation, and ovarian development(Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2025) Mokhtar, Doaa M.Fish ovaries exhibit a remarkable diversity in shape, size, and organization, reflecting the myriad reproductive strategies employed by different species. This review delves into the intricate biology of fish ovaries, highlighting their structural diversity and the hormonal regulation that governs ovarian development and oocyte maturation. Key hormones include pituitary gonadotropins (GTHs) and maturation-inducing hormones (MIHs), which initiate oocyte growth and maturation. GTHs stimulate ovarian production of estradiol-17β and 17α,20β-DP, which induce oocyte maturation via MPF formation. Sex steroids like estrogens and progestogens, synthesized from cholesterol, play crucial roles. Other hormones, including growth hormone, prolactin, thyroid hormones, IGFs, ACTH, and melatonin, influence ovarian activity. The review also explores the varied reproductive strategies among fish, including oviparity and viviparity, and discusses how environmental factors like water temperature and photoperiod influence ovarian histology. Understanding the complex interplay between these factors is essential for advancing fisheries management, conservation, and aquaculture practices. Additionally, the evolutionary trajectory of fish ovaries underscores their adaptation to diverse ecological niches, contributing to the survival and reproductive success of fish species. The ovarian stroma provides structural support and houses various cell types, including dendritic cells (DCs), endocrine cells, and telocytes, contributing to follicle growth and hormone production, essential for reproductive success in fish. Fish ovaries are a crucial aspect of fish biology, with their structure and function intricately regulated by hormonal, environmental, and seasonal factors.
- PublicationRestrictedEffect of dietary supplementation of probiotics and palm fruits extracts on the antioxidant enzyme gene expression in the mucosae of gilthead seabream (Sparus aurata L.)(Elsevier, 2014-07) Cordero, H; Martínez Tomé, Magdalena; Jiménez Monreal, A.M; Bakhrouf, A; Mahdhi, A; Esteban Abad, María de los Ángeles; Tecnología de Alimentos, Nutrición y BromatologíaAntioxidant activity is particularly important, since oxidation is an unavoidable reaction in all living bodies. At present, natural antioxidants to be used on food as an alternative to synthetic ones are being sought. Gilthead seabream (Sparus aurata L.) specimens were fed for 4 weeks with diets enriched with bacterial probiotics (Shewanella putrefaciens Pdp11 and Bacillus sp), single or in combination with Tunisian dates palm fruit extracts. The expression of the main antioxidant enzyme genes (superoxide dismutase, catalase and glutathione reductase) in the mucosae (gut, skin and gill) was evaluated after 2 and 4 weeks. Previously, free radical scavenging and several antioxidant assays were developed to know the antioxidant properties present on the palm fruits extracts. The results demonstrated that experimental diets alter the expression of the studied antioxidant genes, primarily in the gill and skin. Furthermore, the tested probiotics and mainly, the aqueous date palm fruits extracts had significant antioxidant properties based on their protective effect against the levels of intracellular reactive oxygen species, especially when administering during 4 weeks. For this reason, probiotics and date palm fruit extracts may serve as good natural antioxidants and could potentially be considered as a functional food ingredient for fish in farms.
- PublicationRestrictedEvolution of Lipopolysaccharide (LPS) Recognition and Signaling: Fish TLR4 Does Not Recognize LPS and Negatively Regulates NF-κB Activation(American Association of Immunologists Oxford University Press, 2009-02-15) Alcaraz-Perez, Francisca; López-Muñoz, Azucena; Meseguer Peñalver, J.; Cayuela Fuentes, Maria Luisa; Mulero Méndez, Victoriano Francisco; Sepulcre Cortés, María Pilar; Roca Soler, Francisco José; Bioquímica y Biología Molecular B e InmunologíaIt has long been established that lower vertebrates, most notably fish and amphibians, are resistant to the toxic effect of LPS. Furthermore, the lack of a TLR4 ortholog in some fish species and the lack of the essential costimulatory molecules for LPS activation via TLR4 (i.e., myeloid differentiation protein 2 (MD-2) and CD14) in all the fish genomes and expressed sequence tag databases available led us to hypothesize that the mechanism of LPS recognition in fish may be different from that of mammals. To shed light on the role of fish TLRs in LPS recognition, a dual-luciferase reporter assay to study NF-κB activation in whole zebrafish embryos was developed and three different bony fish models were studied: 1) the gilthead seabream (Sparus aurata, Perciformes), an immunological-tractable teleost model in which the presence of a TLR4 ortholog is unknown; 2) the spotted green pufferfish (Tetraodon nigroviridis, Tetraodontiformes), which lacks a TLR4 ortholog; and 3) the zebrafish (Danio rerio, Cypriniformes), which possesses two TLR4 orthologs. Our results show that LPS signaled via a TLR4- and MyD88-independent manner in fish, and, surprisingly, that the zebrafish TLR4 orthologs negatively regulated the MyD88-dependent signaling pathway. We think that the identification of TLR4 as a negative regulator of TLR signaling in the zebrafish, together with the absence of this receptor in most fish species, explains the resistance of fish to endotoxic shock and supports the idea that the TLR4 receptor complex for LPS recognition arose after the divergence of fish and tetrapods.
- PublicationOpen AccessGlial cell line-derived neurotrophic factor expression in the brain of adult zebrafish. Danio rerio(Murcia : F. Hernández, 2008) Lucini, C.; Maruccio, L.; Patruno, M.; Tafuri, S.; Staibano, S.; Mascarello, F.; Castaldo, L.In mammals, glial cell line-derived neurotrophic factor (GDNF) is a growth factor of many neuronal populations in the central, peripheral and autonomous nervous system. GDNF may also function as a morphogen during kidney development and may regulate spermatogonial differentiation. GDNF has been characterised in zebrafish embryos and was demonstrated experimentally to be critical for the development of the enteric nervous system. However, in adult zebrafish, no data exist regarding GDNF expression and localisation in the brain and in different organs. Thus, the aim of the present study was to investigate the expression of GDNF in the brain of adult zebrafish (Danio rerio). Transcripts of GDNF mRNA were observed in brain extracts by a standard RT-PCR. The presence of the protein in the brain homogenates was confirmed by SDS-PAGE electrophoresis and Western blotting analysis. Immunohistochemistry and in situ hybridization experiments showed that GDNF protein and mRNA were localised in various nuclei of the telencephalon, diencephalon, mesencephalon, cerebellum and medulla oblongata of the zebrafish brain. In conclusion, this study showed that the expression of GDNF was not restricted to developmental periods but it seems that this factor might be involved in adult zebrafish brain physiology, as observed in mammals.
- PublicationOpen Accessldentification of extraretinal photoreceptors in the teleost Phoxinus phoxinus(Murcia : F. Hernández, 2004) Álvarez-Viejo, M.; Cernuda-Cernuda, R.; Álvarez-López, C.; García-Fernández, J.M.The existence of cells capable of detecting changes of the photoperiod within the deep brain, the socalled deep brain photoreceptors, was proposed in the early years of the twentieth century. By using immunocytochemistry with antisera against phototransductory proteins on paraffin and vibratome sections, we have localized severa1 positive areas in the brain of the teleost Phoxinus phoxinus. These areas were restricted to two encephalic regions: the epithalamus and the hypothalamus. Immunopositive (rod-opsin- and a-transducin-like) pinealocytes and parapinealocytes, as well as some sparse neurons in the habenula, were seen in the epithalamus. The irnmunoreaction of the hypothalamus was represented by a-transducin-like positive (magnocellular and parvicellular) neurons of the Nucleus Preopticus, as well as by a-transducin- and arrestin-like positive fibers corresponding to the hypothalamic-hypophyseal tract and a few fibers running towards the basa1 telencephalon. These findings corroborate the data published on other teleost fish and fully support the hypothesis of the presence of photosensitive cells in the encephalon of lower vertebrates. The labelling with antisera against different components of the phototransductory cascade also strengthens the idea that such cells employ a biochemical mechanism similar to that in the retinal visual photoreceptor cells, rods and cones. Although the function is still unclear, the detection of the photoperiod seems to be the most likely role for these extraretinal photoreceptors.
- PublicationOpen AccessLectin-binding pattern of Senegalese sole Solea senegalensis (Kaup) testis(Murcia : F. Hernández, 2010) Desantis, S.; Zizza, S.; García-López, A.; Sciscioli, V.; Mañanos, E.; De Metrio, V.G.; Sarasquete, C.The localization and characterization of oligosaccharide sequences in the testis of Senegalese sole Solea senegalensis was investigated using 12 lectins in combination with KOH saponification and sialidase digestion (K-s). The interstitial compartment contained all the sugar residues investigated, those bearing oligosaccharides terminating with sialic acid (Neu5Ac) α2,3Galß1,4GlcNAc, Neu5AcGalNAcα1,3(LFucß1,2)Galß1,3/4GlcNAcß1 and GalNAcα1,3(LFuc1,2)Galß1,3/4GlcNAcß1 being more abundant in the medullar region than in the cortex. The melano-macrophage centres found in the interstitial compartment displayed glycans terminating with Galß1,3GalNAc. The basal lamina separating the germinal and interstitial compartments exhibited glycans with terminal/internal mannose, internal ßGlcNAc, and terminal Neu5Acα2,6Gal/GalNAc, and Neu5AcGalß1,3GalNAc, Galß1,3GalNAc (PNA), Galß1,4GlcNAc, GalNAc, αGal, and αL-Fuc. In the germinal compartment, the Sertoli cells expressed only glycans terminating with Neu5Acα2,3Galß1,4GlcNAc in the apical and supra-nuclear lateral surface of the spermatonial cysts located in the distal part of the seminiferous lobules. Primary spermatocytes exhibited oligosaccharides terminating with Galß1,3GalNAc and αGalNAc in the cytoplasm and nucleus, respectively. The spermatids contained highly mannosylated glycans terminating with GalNac, αGal, and αL-Fuc. The head of spermatozoa expressed a more complex glycosylation pattern characterized by the additional presence of oligosaccharides terminating with Neu5Acα2,3Galß1,4GlcNAc, Neu5AcGalß1,3GalNAc, Neu5AcGalNAcα1,3(LFucα1,2)Galß1,3/4GlcNAcß1, GalNAcα1,3(LFucα1,2)Galß1,3/4GlcNAcß1. The comparison with previous lectin histochemical studies carried out in other fish species reveals a specific glycosylation pattern of Senegalese sole testicular structures and spermatozoa head
- PublicationOpen AccessMale reproductive system in Senegalese sole Solea senegalensis (Kaup): Anatomy, histology and histochemistry(Murcia : F. Hernández, 2005) García-López, A.; Martínez Rodríguez, G.; Sarasquete, C.Despite the fact that the Senegalese sole Solea senegalensis is a target species for the aquaculture industry in Spain and Portugal, very little is known about its gametogenesis and especially about testicular development. Therefore, the male reproductive system in adult S. senegalensis was described using a histological and histochemical approach. Mean gonadosomatic index was very low (0.094±0.004%) and suffered slight changes throughout the experimental period. In transverse sections, the testis presents a reniform structure with two main regions, a cortical one with seminiferous lobules where germ cells proliferate in spermatocysts (germ /Sertoli cells units), and a medullar one with spermatic ducts that collect and store the produced sperm. The germinal compartment is organized into branching lobules of the unrestricted spermatogonial type, although the majority of type A spermatogonia are located at the distal part of the lobules. Spermatogenesis seems to be semi-cystic, since spermatids are released into the lobule lumen, where they are transformed into spermatozoa. Proteins in general, especially those rich in arginine, and carboxylated mucosubstances/glycoproteins increased from spermatogonia to spermatozoa. 3ß-Hydroxysteroid dehydrogenase enzymatic activity was exclusively observed in Leydig cells. The present study provides the first precise description of male reproductive apparatus in S. senegalensis.
- PublicationOpen AccessMelanization stimulating factors in the integument of the Mugil cephalus and Dicertranchus labrax(Murcia : F. Hernández, 2000) Zuasti, A.; Martínez Liarte, José Hilario; Solano, F.; Ferrer, C.The pigment pattern expression resides in the chromatoblasts of the embryonic skin. The differentiation of these chromatoblasts is influenced by specific local factors such a melanization inhibiting factor (MIF) and a melanization-stimulating factor (MSF). We reveal the presence of these factors by means of a series of experiments on the skin of the marine species of fish Dicertranchus labrax and Mugil cephalus, each with different pigment pattern, the former having a light skin and the latter a darker one. Media conditioned by exposure to dorsal andtor ventral skin, stimulates the melanization of Xenopus laevis neural crest cells throughout a 3 day assay period. Similarly conditioned culture media tested on B16-F10 murine malignant melanocytes, revealed a considerable influence in enzymatic activities: dopachrome tautomerase (DCT), tyrosine hydroxylase and dopa oxidase. The use of media in a dose response basis suggests that the conditioned media may contain both melanophore stimulating and inhibiting factors. The results obtained may actually reflect the resultant activity of the two factors present.
- PublicationOpen AccessTerminal carbohydrates abundance, immune related enzymes, bactericidal activity and physico-chemical parameters of the Senegalese sole (Solea senegalensis, Kaup) skin mucus(Elsevier , 2016-11-09) Collado-González, Mar; Guardiola Abellán, Francisco Antonio; Cuartero, María; Díaz Baños, F. Guillermo; Cuesta Peñafiel, Alberto; Moriñigo, Miguel Angel; Esteban Abad, María de los Ángeles; Biología Celular e HistologíaRecently, interest in mucosal surfaces, more specifically fish skin and its secreted mucus, has greatly increased among immunologists. The abundance of terminal carbohydrates, several enzymes (proteases, lysozyme, peroxidase, alkaline phosphatase, esterases and ceruloplasmin), bactericidal activity against fish pathogenic and non-pathogenic bacteria and several physico-chemical parameters (protein concentration, pH, conductivity, redox potential, osmolarity, density and viscosity) in the skin mucus of Senegalese sole (Solea senegalensis, Kaup) have been evaluated. Present results evidence the abundance of N-acetylneuraminic acid, mannose, glucose and N-acetyl-galactosamine in skin mucus. The levels of lysozyme, proteases, esterases and alkaline phosphatase were very similar (from 20 to 30 Units mg−1 protein). However, 93 Units mg−1 protein were detected of ceruloplasmin and only 4′88 Units mg−1 protein of peroxidase. Skin mucus of S. senegalensis showed high bactericidal activity against the tested pathogen bacteria but weak activity against non-pathogenic bacteria. Finally, a clear relationship between mucus density and temperature was detected, while viscosity showed a direct shear- and temperature-dependent behaviour. These results could be useful for better understanding the role of the skin mucus as a key component of the innate immune system, as well as, for elucidating possible relationships between biological and physico-chemical parameters and disease susceptibility.
- PublicationOpen AccessThe retinal pigment epithelium of the teleost Notopterus notopterus (Pallas): Appearance of basal infoldings during prolonged dark-adaptation(Murcia : F. Hernández, 2004) Nag, T.C.In teleosts, the basal part of the retinal pigment epithelium (RPE) is relatively smooth, i. e., it is free of basal membrane infoldings. In the featherback, Notopterus notopterus, whereas this is the situation in light adaptation, during dark-adaptation, especially when kept for prolonged periods (6-9 hour), numerous infoldings appear at the basal region, as found uniquely by transmission electron microscopy. In this teleost, during retinomotor movements, the rods move vitreally during dark-adaptation, while the cones do not elongate, and remain stationary in both light- and dark- adaptation. The significance of the appearance of basal infoldings in dark-adapted RPE is explained in terms of the pattern of retinomotor responses and the features of RPE and photoreceptors in this species. It is suggested that (1) the thick, impervious tapetal layer present in the RPE, (2) the unusual position of the photoreceptors in the visual cell layer of dark-adapted retina, and (3) the presumably high demand for glucose and O2 of the outer retina during dark-adaptation might contribute to cause this phenomenon in this species. The available evidence tend to associate this phenomenon with the involvement of the RPE in nutrient and O2 delivery to the photoreceptors via the basal infoldings of the RPE in dark-adapted state in this species. This has not been reported for any other teleosts to date.