DigitalUM :: Browsing by Subject "Fish"

Browsing by Subject "Fish"

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Open Access
Acidophilic granulocytes of the marine fish gilthead seabream (Sparus aurata L.) produce interleukin-1b following infection with Vibrio anguillarum
(Springer, 2004) Chaves-Pozo, Elena; Pelegrin, Pablo; García-Castillo, Jesús; Meseguer, José; García Ayala, Alfonsa; Mulero Méndez, Victoriano Francisco; Bioquímica y Biología Molecular B e Inmunología
The fish immune response to Gram-negative bacteria is poorly understood. In this study, we use a monoclonal antibody (mAb) specific to acidophilic granulocytes from the marine fish gilthead seabream (Sparus aurata L.), together with an antiserum specific to interleukin-1b (IL-1b) from this species, in order to investigate whether these cells are involved in the immune response against the pathogenic bacterium Vibrio anguillarum and, in particular, in the production of the pro-inflammatory cytokine IL-1b. We found that gilthead seabream head- kidney, peritoneal exudate and peripheral blood leukocytes accumulated proIL-1b intracellularly when challenged in vitro with V. anguillarum, whereas only peritoneal exudate and blood leukocytes were able to accumulate proIL-1b following infection. Importantly, the blood leukocytes from infected animals that accumulated proIL-1b were shown to be the acidophilic granulocytes. A rapid mobilization of such cells from the head-kidney to the site of inflammation following infection with V. anguillarum was also observed.
Open Access
Age-related changes in mitochondrial membrane composition of Nothobranchius furzeri. Comparison with a longer-living Nothobranchius species
(Springer Nature, 2019-02-15) Almaida Pagán, Pedro Francisco; Ortega-Sabater C.; Lucas-Sanchez A.; Gonzalez-Silvera D.; Martinez-Nicolas A.; Rol de Lama, María de los Ángeles; Mendiola P.; de Costa J.; Fisiología
Membrane compositions, particularly of mitochondria, could be critical factors in the mechanisms of growth and aging, especially during phases of high oxidative stress that result in molecular damage. Changes affecting lipid class or fatty acid (FA) compositions could affect phospholipid (PL) properties and alter mitochondrial function. In the present study, mitochondrial membrane PL compositions were analysed throughout the life-cycle of Nothobranchius furzeri, a species with explosive growth and one of the shortest-lived vertebrates. Mitochondrial PLs showed several changes with age. Proportions of total PLs and PC were reduced while an increase in PS, CL and PE was observed, mainly between the 2.5 and 5 months of fish age, the time during which animals doubled their weight. FA compositions of individual PLs in mitochondria were also significantly affected with age suggesting the existence of increasing damage to mitochondrial lipids during the life- cycle of N. furzeri that could be one of the main contributors to degraded mitochondrial function associated with aging. The peroxidation index values from N. furzeri mitochondrial PLs were significantly lower than those reported in N. rachovii, a species with a 2-fold longer life span than N. furzeri, which seems to contradict the membrane pacemaker theory of animal metabolism
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Age-related changes in mitochondrial membrane composition of Nothobranchius furzeri: comparison with a longer-living Nothobranchius species
(Springer, 2018-10-09) Almaida Pagán, Pedro Francisco; Ortega-Sabater, C; Lucas-Sanchez, A; Gonzalez Silvera, D; Martinez-Nicolas, A; Rol, M A; Mendiola, P; Costa, J. de; Chronobiology Lab, Department of Physiology, College of Biology, University of Murcia, Mare Nostrum Campus, IUIE, IMIB-Arrixaca, Murcia, Spain; Ciber Fragilidad y Envejecimiento Saludable (CIBERFES), Madrid, Spain; Department of Cell Biology, College of Biology, University of Murcia, Murcia, Spain
Membrane compositions, particularly of mitochondria, could be critical factors in the mechanisms of growth and aging, especially during phases of high oxidative stress that result in molecular damage. Changes affecting lipid class or fatty acid (FA) compositions could affect phospholipid (PL) properties and alter mitochondrial function. In the present study, mitochondrial membrane PL compositions were analysed throughout the life-cycle of Nothobranchius furzeri, a species with explosive growth and one of the shortest-lived vertebrates. Mitochondrial PLs showed several changes with age. Proportions of total PLs and PC were reduced while an increase in PS, CL and PE was observed, mainly between the 2.5 and 5 months of fish age, the time during which animals doubled their weight. FA compositions of individual PLs in mitochondria were also significantly affected with age suggesting the existence of increasing damage to mitochondrial lipids during the life-cycle of N. furzeri that could be one of the main contributors to degraded mitochondrial function associated with aging. The peroxidation index values from N. furzeri mitochondrial PLs were significantly lower than those reported in N. rachovii, a species with a two-fold longer life span than N. furzeri, which seems to contradict the membrane pacemaker theory of animal metabolism.
Embargo
Age-related changes in mitochondrial membrane composition of nothobranchius rachovii
(Oxford University Press, 2013-05-17) Lucas-Sánchez, Alejandro; Almaida Pagán, Pedro Francisco; Tocher, Douglas R.; Mendiola, Pilar; Costa, Jorge de; Fisiología
Mitochondrial membrane composition may be a critical factor in the mechanisms of the aging process by influencing the propagation of reactions involved in mitochondrial function during periods of high stress. Changes affecting either lipid class or fatty acid compositions could affect phospholipid properties and alter mitochondrial function and cell viability In the present study, mitochondrial membrane phospholipid compositions were analyzed throughout the life cycle of Nothobranchius rachovii. Mitochondrial phospholipids showed several changes with age. Proportions of cardiolipin decreased and those of sphingomyelin increased between 11- and 14-month-old fish. Fatty acid compositions of individual phospholipids in mitochondria were also significantly affected with age. These data suggest increasing damage to mitochondrial lipids during the life cycle of N. rachovii that could be one of the main factors related with and contributing to degraded mitochondrial function associated with the aging process.
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Age-related changes in mitochondrial membrane composition of rainbow trout (Oncorhynchus mykiss) heart and brain
(Elsevier, 2012-05-22) Almaida Pagán, Pedro Francisco; Costa, J. de; Mendiola, P; Tocher, D R; Fisiología; Institute of Aquaculture, School of Natural Sciences, University of Stirling, Stirling FK9 4LA, Scotland, United Kingdom; Department of Physiology, Faculty of Biology, University of Murcia, 30100 Murcia, Spain
Membrane composition, particularly of mitochondria, could be a critical factor by determining the propaga-tion of reactions involved in mitochondrial function during periods of high oxidative stress such as rapid growth and aging. Considering that phospholipids not only contribute to the structural and physical properties of biological membranes, but also participate actively in cell signaling and apoptosis, changes affecting either class or fatty acid compositions could affect phospholipid properties and, thus, alter mitochondrial function and cell viability. In the present study, heart and brain mitochondrial membrane phospholipid compositions were analyzed in rainbow trout during the four first years of life, a period characterized by rapid growth and a sustained high metabolic rate. Specifically, farmed fish of three ages (1-, 2- and 4-years) were studied, and phospholipid class compositions of heart and brain mitochondria, and fatty acid compositions of individual phospholipid classes were determined. Rainbow trout heart and brain mitochon- dria showed different phospholipid compositions (class and fatty acid), likely related to tissue-specific functions. Furthermore, changes in phospholipid class and fatty acid compositions with age were also tissue-dependent. Heart mitochondria had lower proportions of cardiolipin (CL), phosphatidylserine (PS) and phosphatidylinositol, and higher levels of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) with age. Heart mitochondrial membranes became more unsaturated with age, with a significative increase of peroxidation index in CL, PS and sphingomyelin (SM). Therefore, heart mitochondria became more susceptible to oxidative damage with age. In contrast, brain mitochondrial PC and PS content decreased in 4-year-old animals while there was an increase in the proportion of SM. The three main phospholipid classes in brain (PC, PE and PS) showed decreased n−3 polyunsaturated fatty acids, docosahexaenoic acid and peroxidation index, which indicate a different response of brain mitochondrial lipids to rapid growth and maturation.
Open Access
Analysis of gene status in cervical dysplastic lesions and squamous cell carcinoma using tissue microarrays
(Murcia : F. Hernández, 2009) Costa, C.; Espinet, Blanca; Molina, Miguel A.; Salgado, Rocio; Salido, M.; Baró, Teresa; Fusté, P.; Mancebo, G.; Carreras, R.; Solé, Francesc; Serrano, S.; Alameda, F.
Cervical displasia are classified as CIN-I, CIN-II and CIN-III. It has been observed that in at least 60% of CIN-I and CIN-II, the pathology disappears spontaneously, while around 30% persist at 24 months, 10% progress to CIN-III and 1% develops as a SCC. The factors involved in the evolution of the pathology are not defined, although infection of HPV is a necessary condition, but not the only one. For this reason, the identification of genetic changes is an essential element for understanding the carcinogenic process. It can also serve as a helpful tool for identifying patients who may be susceptible to its evolution and treatment, from patients whose lesions could regress spontaneous and for whom periodic follow-ups would be enough. Fiftty three cervical biopsies from patients with dysplasia and ISCC were included in the study. These biopsies were set into nine macroarrays. Eight genes and five proteins were examined in each samples (hTERT, PIK3CA, hTERC, MYC, CCND1, BCL2, ZNF217 and p16) by fluorescence in situ hybridization (FISH) and/or immunohistochemistry (IHC). The results reflected that the genetic alterations of PIK3CA, ZNF217 and CCND1 were associated with the evolution of normal tissue to CIN I, those of hTERC and ERBB with the evolution of LSIL to HSIL, those of hTERT and MYC with the evolution of CIN-II/CIN-III to ISCC, and those of BCL-2 with the inception of ISCC. With regards to proteins, the expression of MYC and CCND1 in the initial stages of the illness would help in the acquisition of the altered cellular phenotype.
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Changes in tissue and mitochondrial membrane composition during rapid growth, maturation and aging in rainbow trout, Oncorhynchus mykiss
(Elsevier, 2012-01-16) Almaida Pagán, Pedro Francisco; Costa, J. de; Mendiola, P; Tocher, D R; Fisiología; Institute of Aquaculture, School of Natural Sciences, University of Stirling, Stirling FK9 4LA, Scotland, United Kingdom; Department of Physiology, Faculty of Biology, University of Murcia, 30100 Murcia, Spain
Membrane compositions, particularly of mitochondria, could be critical factors in the mechanisms of growth and aging processes, especially during phases of high oxidative stress that result in molecular damage. In the present study, liver and mitochondrial membrane phospholipid (PL) compositions were analyzed in rainbow trout during its four first years of life, a period characterized by rapid growth and high oxidative stress. Specifically, farmed fish of three ages (1-, 2- and 4-years) were studied, and PL compositions of whole liver and liver mitochondria, and fatty acid compositions of individual PL classes were determined. Liver mitochondrial membranes showed a PL composition different to that of the whole tissue suggesting adaptation of cell and subcellular membranes to specific functions. Individual PL had characteristic fatty acid compositions that were similar in whole liver and mitochondrial membranes. Whole liver and mitochondria showed increased lipid peroxidation with age along with changes in membrane PL fatty acid compositions. Most PL classes showed similar changes in fatty acid composition among the age groups, with reduced proportions of docosahexaenoic acid (DHA) and, generally, concomitantly increased levels of monounsaturated fatty acids, which together resulted in reduced peroxidation index (PIn). However, total polyunsaturated fatty acid (PUFA) content did not change significantly with age due to increased eicosapentaenoic acid, docosapentaenoic acid and, in most PL, increased n−6 PUFA. These results suggest there may be oxidation of PL DHA with compensatory mechanisms to maintain membrane fluidity and function. However, modification of fatty acid composition of specific PLs, such as cardiolipin, could affect the electron transport chain efficiency and propagate the oxidative reaction throughout the cell. In addition, both the content and fatty acid composition of sphingomyelin, which has been suggested as a possible mediator of cell dysfunction and apoptosis, changed with age differently to the other PL classes. Moreover, these changes showed different trends between mitochondria and whole liver. These data suggest there is marked oxidative stress associated with rapid growth and maturation in rainbow trout. Changes observed in membrane lipids point to their possible participation in the processes involved in this species response to oxidative stress and damage accumulation rate.
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Comparative analysis of the olfactory organs in selected species of marine sharks and freshwater batoids
(Elsevier GmbH, 2021-07-29) Dymek, Jakub; Muñoz, Pilar; Mayo-Hernández, Elvira; Kuciel, Michał; Zuwała, Krystyna; Sanidad Animal
We present comparative analysis of the micro- and macro-morphology of the olfactory organ of six neoselachians living in different habitats: two freshwater benthopelagic batoids, Potamotrygon motoro and Potamotrygon hystrix (Potamotrygonidae) as well as four species of sharks occupying the outer continental shelves and upper slopes Mustelus mustelus (Trikidae) and Scyliorhinus canicula (Scyliorhinidae), and deep-water Galeus melastomus (Scyliorhinidae) and Etmopterus spinax (Etmopteridae). Our research used light and electron (TEM, SEM) microscopes as well as macroscopic observations. The position of the nostrils in relation to the mouth varied in these species but all of them possessed elongate olfactory rosettes with primary lamellae arranged over two rows. The types of primary lamellae were distinguished based on their arrangement on the opposite sides of the median raphe as well as morphology of secondary lamellae and distribution of sensory and non-sensory regions of olfactory epithelium lining the lamellae; these were different between batoids and sharks. Analysis of olfactory epithelium revealed the presence of microvillous olfactory sensory neurons as the only type of receptor cells in all studied species whereas ionocytes were recognized only in sharks. All species possessed one type of goblet cells (Alcian Blue or Periodic Acid Schiff positives) except for P. motoro in which both types of goblet cells were present. Moreover, apical parts of non-sensory microvillous cells that lined the basal parts of the primary lamellae, possessed PAS-positive mucous granules; these were present in both species of batoids. This analogous region was abundant in goblet cells in the species of sharks studied here. Results indicated that differences between freshwater and marine species as well as between marine species occupying various habitat zones include mainly nostrils position, density of occurrence of ionocytes and goblet cells within olfactory epithelium as well as biochemical character of mucus
Open Access
Comparative study of MLPA-FISH to determine DNA copy number alterations in neuroblastic tumors
(Murcia: F. Hernández, 2011) Villamón, E.; Piqueras, M.; Berbegall, A.P.; Tadeo, I.; Castel, V.; Navarro, S.; Noguera, R.
Neuroblastoma tumor cells show complex combinations of genetic aberrations, and to date many different methods have been used for their detection. To apply genome-wide techniques, such as Multiplex Ligation–dependent Probe Amplification (MLPA), in routine diagnosis their validation is appropriate and necessary. DNA copy number alterations in 129 cases of neuroblastic tumors were detected using MPLA, and the results validated by Fluorescence In Situ Hybridization (FISH) (MYCN gene, 1p36, 11q and 17q). Kappa index values showed very good concordance between the two techniques in detecting homogeneous MYCN amplification (1); 11q deletion (0.908) and 17q gain (0.922). The validation results showed that MLPA is a highly efficient technique for diagnosis based on the genetic aberrations in relevant regions in neuroblastoma, showing a high concordance with FISH.
Open Access
Description 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 Histología
The 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.
Open Access
Effect of masking organoleptic properties of fat on diet self-selection by the sparid Diplodus puntazzo
(Blackwell Publishing Ltd., 2009) Almaida Pagán, Pedro Francisco; Hernandez, M.D.; Madrid, Juan A.; Costa, J. de; Mendiola, P.; Fisiología
Fish are able to select a balanced diet according to their nutritional needs by choosing among incomplete feeds or even pure macronutrients. However, the relevance of both the organoleptic properties of diet and the postingestive signals that they produce remains unclear. Thus, sharpsnout seabream were allowed to select between diets containing different edible oils with their organoleptic properties masked by using gelatine capsules. Fish were fed capsules of two different colours so that they could associate the capsule colour with its corresponding postingestive effect. The longitudinal experiment included a first phase during which the fish were adapted to consuming the gelatine capsules. In a second phase, the fish were challenged with two different encapsulated diets: one comprising a complete diet containing fish oil and the other a fat-free diet. Sharpsnout seabream showed a preference for the fish oil capsules (3.8 ± 1.1 g kg)1 body weight (BW), 66.8% of total intake) over the fat-free capsules, showing that they were able to associate the colour of the capsule with their nutritional content through postingestive signals. After that, the fish were challenged to select between the capsules containing the fish oil diet and capsules containing a vegetable oil (linseed or soybean), in which case they showed no preference between diets (2.4 ± 0.3: 2.1 ± 0.5 g kg-1 BW of fish oil versus linseed oil capsules and 2.2 ± 0.2: 1.8 ± 0.6 g kg-1 BW of fish oil versus soybean oil capsules), indicating that the fatty acid composition of the different oils was not sufficient to affect dietary selection through postingestive signals. So, in conclusion, when orosensorial information from food is absent, the fish are able to select between diets at a macronutrient level by using postingestive information. However, this information is not sufficient for distinguishing between diets that differ in the type of oil used.
Open Access
Electron microscopic perspectives of gil1 pathology induced by 1-naphthyl-N- methylcarbamate in the goldfish (Carassius auratus Linnaeus)
(Murcia : F. Hernández, 1997) Pfeiffer, C.J.; Qiu, B.; Cho, C.H.
This experiment has clarified the ultrastructural pathology, by scanning (SEM) and transmission electron microscopy (TEM), induced by 1- naphthyl-N- methylcarbamate (carbaryl) in the gills of juvenile goldfish (Carassius auratus Linneaus). Carbaryl is a low toxicity pesticide commonly used in forestry and agriculture and for controlling aquatic weeds and crustacean predators of shellfish, and has been known to cause gill damage in fish and clams. A variety of cellular changes were observed after exposure of goldfish for 96 h to a sublethal dose of 10 mg carbaryul of water. SEM revealed secondary lamellar fusion, distortion, thinning, and mucus release. TEM responses included enlargement of subepithelial lymphatic spaces and mitochondrial disruption and distortion of the lamellar covering epithelium. Pillar cells became detached and chloride cells were vacuolated. Fish were able to withstand these changes in subacute experiments due to redundacy in gill surface area.
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Energy intake and macronutrient selection in sharpsnout seabream (Diplodus puntazzo) challenged with fat dilution and fat deprivation using encapsulated diets
(Elsevier, 2008-02-27) Almaida Pagán, Pedro Francisco; Hernandez, M D; Madrid, Juan A; Costa, J de; Mendiola, P; Seco Rovira, Vicente; Fisiología; IMIDA-Acuicultura, Consejería de Agricultura y Agua de la Región de Murcia, Apdo.65.30740, San Pedro del Pinatar, Murcia, Spain
Sharpsnout seabream fed pure macronutrient capsules were challenged to fat dilution and fat deprivation in order to investigate the effects of fat level on energy intake regulation and macronutrient selection by fish, as they lack oropharyngeal chemosensory information from the diet. During the control phase, the fish were fed three individually encapsulated macronutrients, from which they composed a diet containing 67.36% protein (P), 19.08% carbohydrates (CH) and 13.57% fat (F), in terms of macronutrient weight intake percentage. During the second phase of the experiment, a lipid content reduction in F capsules from 55.0% to 13.4% did not significantly modify this selection pattern, energy ingestion or the number of capsules ingested of each macronutrient. During the third phase, in which they were subjected to fat deprivation, starting on almost the first day, the fish increased their total energy intake and total ingested number of capsules. These results reveal that fish are capable of distinguishing and selecting each of the three macronutrients contained in gelatine capsules, and that fish selection of a balanced diet from pure macronutrients is remarkably stable. Fish are capable of sustaining their macronutrient selection pattern and energy intake with very low amounts of fat in their diets (Phase 2). A certain instability in the initial P, CH and energy intake was only observed when fat was totally deprived (Phase 3), which resulted in higher values than those observed in Phase 1. In order to examine any possible effects of diet encapsulation, digestibility assays were performed in a second experiment. The fish were divided into two experimental groups and fed the same complete commercial diet, the only difference being the way it was presented to each group (pelleted or encapsulated). No statistical differences between the experimental groups were found with regards to both apparent digestibility coefficients and fish growth.
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Enzymatic activity changes in striped catfish Pseudoplatystoma magdaleniatum, induced by exposure to different concentrations of ibuprofen and triclosan.
(Elsevier, 2021-05) Gallego Rios, Sara E.; Peñuela, Gustavo A.; Martínez-López, Emma; Ciencias Sociosanitarias
The present study aimed to evaluate the effects of exposure for four months, with ibuprofen and triclosan at 25 and 50 μg/L in Striped catfish Pseudoplatystoma magdaleniatum, evaluated between sexes and exposure times. Biochemical biomarkers such as lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma-glutamyltransferase, acetylcholinesterase, creatine kinase, lipid peroxidation, albumin, globulins, creatinine, and urea were evaluated. The results of this study suggest that both ibuprofen and triclosan at concentrations of 25 and 50 μg/L can cause alterations to P. magdaleniatum, interfering with the activity of certain enzymes associated with energy production, immune response, architecture, and cellular physiology. Also, we determined the current state of contamination in fish, the concentration of ibuprofen and triclosan in P. magdaleniatum muscle samples from the different places markets located on the banks of the main rivers of Colombia was quantified by UHPLC-QqQ-MS/MS, in three climatic periods; finding triclosan levels in the dry season in some of the sampling points compatible with enzyme-level alterations in this species.
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Evolution 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 Inmunología
It 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.
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Evolution of the inflammatory response in vertebrates: fish TNF-α is a powerful activator of endothelial cells but hardly activates phagocytes
Mulero Méndez, Iván; López-Muñoz, Azucena; Renshaw, Stephen A.; Meseguer Peñalver, J.; Mulero Méndez, Victoriano Francisco; Sepulcre Cortés, María Pilar; Roca Soler, Francisco José; Bioquímica y Biología Molecular B e Inmunología
TNF-α is conserved in all vertebrate classes and has been identified in all taxonomic groups of teleost fish. However, its biological activities and its role in infection are largely unknown. Using two complementary fish models, gilthead seabream and zebrafish, we report here that the main proinflammatory effects of fish TNF-α are mediated through the activation of endothelial cells. Thus, TNF-α promotes the expression of E-selectin and different CC and CXC chemokines in endothelial cells, thus explaining the recruitment and activation of phagocytes observed in vivo in both species. We also found that TLR ligands, and to some extent TNF-α, were able to increase the expression of MHC class II and CD83 in endothelial cells, which might suggest a role for fish endothelial cells and TNF-α in Ag presentation. Lastly, we found that TNF-α increases the susceptibility of the zebrafish to viral (spring viremia of carp virus) and bacterial (Streptococcus iniae) infections. Although the powerful actions of fish TNF-α on endothelial cells suggest that it might facilitate pathogen dissemination, it was found that TNF-α increased antiviral genes and, more importantly, had little effect on the viral load in early infection. In addition, the stimulation of ZF4 cells with TNF-α resulted in increased viral replication. Together, these results indicate that fish TNF-α displays different sorts of bioactivity to their mammalian counterparts and point to the complexity of the evolution that has taken place in the regulation of innate immunity by cytokines.
Open Access
Fine structure of spermatozoa in the common pandora (Pagellus erythrinus Linnaeus, 1758) (Perciformes, Sparidae)
(Murcia : F. Hernández, 2004) Maricchiolo, G.; Genovese, L.; Laurà, R.; Micale, V.; Muglia, U.
Scanning and transmission electron microscopy were used to investigate the fine structure of the sperm of the Sparid fish Pagellus erythrinus L.. The spermatozoon of pandora has a spherical head lacking an acrosome, a cone-shaped midpiece and a long tail. The midpiece houses a single mitochondrion. The centriolar complex lies inside the nuclear fossa and is composed of a proximal and a distal centriole which are arranged at right angles to each other. The flagellum is inserted medio-laterally into the head, contains the conventional 9+2 axoneme and possesses one pair of lateral fins. On the basis of its ultrastructural organization, the pandora sperm can be regarded as an evolved form of the primitive spermatozoon found in Teleosts. According to the morphological classification proposed by Mattei (1970), the sperm of pandora belongs to a “type I” designation, like that of the other Sparid fish.
Open Access
Fine structure of spermatozoa in the gilthead sea bream (Sparus aurata Linnaeus, 1758) (Perciformes, Sparidae)
(Murcia : F. Hernández, 2007) Maricchiolo, G.; Genovese, L.; Laurà, R.; Micale, V.; Muglia, U.
Scanning and transmission electron microscopy were used to investigate the fine structure of the sperm of the sparid fish Sparus aurata L. The mature spermatozoon of gilthead sea bream belongs, like that of the other sparid fish, to a “type I” as defined by Mattei (1970). It has a spherical head which lacks an acrosome, a short, irregularly-shaped midpiece and a long cylindrical tail. The nucleus reveals a deep invagination (nuclear fossa) in which the centriolar complex is located. The two centrioles are approximately perpendicular to each other and show a conventional “9+0” pattern. The proximal centriole is associated with a cross-striated cylindrical body lying inside a peculiar satellite nuclear notch which appears as a narrow invagination of the nuclear fossa. The distal centriole is attached to the nuclear envelope by means of a lateral plate and radial fibres made of an electron-dense material. The short midpiece houses one mitochondrion. The flagellum is inserted perpendicularly into the base of the nucleus and contains the conventional 9+2 axoneme.
Open Access
Fine structure of the retina and pigment epithelium in the creek chub, Semotilus atromaculatus (Cyprinidae, Teleostei)
(Murcia : F. Hernández, 1996) Collin, S.P.; Collin, H.B.; Ali, M.A.
The structure of the light- and dark-adapted retina, the pigment epithelium and the choroid of the creek chub, Semotilus atromaculatus (Cyprinidae, Teleostei) is examined by light and electron microscopy. An extensive network of vitreal blood vessels emanating from the hyaloid artery enters the eye with the optic nerve and overlies the inner limiting membrane. This membrane closely apposes the fine protrusions of the Müller cell processes which traverse the entire retina, dividing the inner retina into alternating fascicles of ganglion cells and optic axons. The inner nuclear layer consists of bipolar, amacrine, Müller cell soma and two layers of horizontal cells. The outer plexiform layer possesses both rod spherules and cone pedicles. Each rod spherule consists of a single synaptic ribbon in either a triad or quadrad junctional arrangement within the invaginating terminal endings of the bipolar and horizontal cell processes. In contrast, cone pedicles possess multiple synaptic ribbons within their junctional complexes and, in the light-adapted state, the horizontal cell processes show spinule formation. Four photoreceptor types are identified on morphological criteria; unequal double cones, large single cones, small single cones and rods. Al1 but the small single cones are capable of retinomotor responses. The rod to cone ratio is approximately 5:l and the rods form two ill-defined rows in the light-adapted condition. The retinal pigment epithelium possesses two types of osmiophilic granules. These are bound within slender microvilli and migrate vitread to surround the photoreceptors in response to light. Bruch's membrane is trilaminar and the vascularised choroid consists of up to three layers of melanocytes. The endothelial borders of the choroidal blood vessels abutting the outer lamina of Bruch's membrane are fenestrated.
Open Access
First data on the movements of Iberochondrostoma almacai (Coelho, Mesquita & Collares-Pereira, 2005) out of dryseason pools in a Mediterranean stream
(Murcia: Servicio de Publicaciones de la Universidad de Murcia, 2013) Pires, Daniel Filipe; Magalhães, María Filomena
Movement out of dry-season refugia may be critical to fish persistence in temporary streams, though it remains poorly understood. Here we quantify the movements by the Southwestern archedmouth nase out of dry-season pools in a mediterranean stream, using a mark-recapture design. Although some nase were sedentary, some individuals moving out of dry-season pools displaced more than 200m, both upstream and downstream, and into persistent and ephemeral sites. This suggests that nase may redistribute after flow resumption and colonize sites that were previously dry.