Browsing by Author "Gavaia, Paulo"
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- Altered bone microarchitecture in a type 1 diabetes mouse model Ins2 (Akita)Publication . Pires De Carvalho, Filipe Ricardo; Calado, Sofia; Silva, Gabriela A.; Diogo, Gabriela S.; Moreira da Silva, Joana; Reis, Rui L.; Cancela, M. Leonor; Gavaia, PauloType 1 diabetes mellitus (T1DM) has been associated to several cartilage and bone alterations including growth retardation, increased fracture risk, and bone loss. To determine the effect of long term diabetes on bone we used adult and aging Ins2 Akita mice that developed T1DM around 3-4 weeks after birth. Both Ins2 Akita and wild-type (WT) mice were analyzed at 4, 6, and 12 months to assess bone parameters such as femur length, growth plate thickness and number of mature and preapoptotic chondrocytes. In addition, bone microarchitecture of the cortical and trabecular regions was measured by microcomputed tomography and gene expression of Adamst-5, Col2, Igf1, Runx2, Acp5, and Oc was quantified by quantitative real-time polymerase chain reaction. Ins2 Akita mice showed a decreased longitudinal growth of the femur that was related to decreased growth plate thickness, lower number of chondrocytes and to a higher number of preapoptotic cells. These changes were associated with higher expression of Adamst-5, suggesting higher cartilage degradation, and with low expression levels of Igf1 and Col2 that reflect the decreased growth ability of diabetic mice. Ins2 Akita bone morphology was characterized by low cortical bone area (Ct.Ar) but higher trabecular bone volume (BV/TV) and expression analysis showed a downregulation of bone markers Acp5, Oc, and Runx2. Serum levels of insulin and leptin were found to be reduced at all-time points Ins2 Akita . We suggest that Ins2 Akita mice bone phenotype is caused by lower bone formation and even lower bone resorption due to insulin deficiency and to a possible relation with low leptin signaling.
- Analysis of sperm quality in a type I diabetes zebrafish modelPublication . Diogo, Patricia; Eufrásio, Ana; Martins, Gil; Cardeira, João; Cancela, M. Leonor; Cabrita, Elsa; Gavaia, PauloDiabetes is a fast growing disease in human populaon and the study of its impact on mammalian reproducve traits has been con-troversial. Some authors showed a negave eect on sperm mol-ity and DNA fragmentaon in some species, while others failed to detect any eects. In the present study zebrash was used as a model to study the eect of diabetes in sperm traits such as mol-ity, viability and DNA fragmentaon
- Anti-osteogenic activity of cadmium in zebrafishPublication . Tarasco, Marco; Cardeira Da Silva, João; Viegas, Michael; Caria, Joana; Martins, Gil; Gavaia, Paulo; Cancela, M. Leonor; Laizé, VincentAmong the many anthropogenic chemicals that end up in the aquatic ecosystem, heavy metals, in particular cadmium, are hazardous compounds that have been shown to affect developmental, reproductive, hepatic, hematological, and immunological functions in teleost fish. There is also evidence that cadmium disturbs bone formation and skeletal development, but data is scarce. In this work, zebrafish was used to further characterize the anti-osteogenic/osteotoxic effects of cadmium and gain insights into underlying mechanisms. Upon exposure to cadmium, a reduction of the opercular bone growth was observed in 6-days post-fertilization (dpf) larvae and an increase in the incidence of skeletal deformities was evidenced in 20-dpf post-larvae. The extent and stiffness of newly formed bone was also affected in adult zebrafish exposed to cadmium while regenerating their caudal fin. A pathway reporter assay revealed a possible role of the MTF-1 and cAMP/PKA signaling pathways in mechanisms of cadmium osteotoxicity, while the expression of genes involved in osteoblast differentiation and matrix production was strongly reduced in cadmium-exposed post-larvae. This work not only confirmed cadmium anti-osteogenic activity and identified targeted pathways and genes, but it also suggested that cadmium may affect biomechanical properties of bone.
- Avanços recentes em nutrição de larvas de peixesPublication . Conceicao, Luis; Aragão, C.; Richard, Nadège; Engrola, S.; Gavaia, Paulo; Mira, Sara; Dias, J.Os requisitos nutricionais de larvas de peixes são ainda mal compreendidos, o que leva a altas mortalidades e problemas de qualidade no seu cultivo. Este trabalho pretende fazer uma revisão de novas metodologias de investigação, tais como estudos com marcadores, genómica populacional, programação nutricional, génomica e proteómica funcionais, e fornecer ainda alguns exemplos das utilizações presentes e perspectivas futuras em estudos de nutrição de larvas de peixes.
- Bioprospecting marine fungi from the plastisphere: osteogenic and antiviral activities of fungal extractsPublication . Furno, Matteo Florio; Laizé, Vincent; Arduino, Irene; Pham, Giang Nam; Spina, Federica; Mehiri, Mohamed; Lembo, David; Gavaia, Paulo; Varese, Giovanna CristinaMarine microplastics (MPs) represent a novel ecological niche, populated by fungi with high potential for pharmaceutical discovery. This study explores the bioactivity of fungal strains isolated from MPs in Mediterranean sediments, focusing on their osteogenic and antiviral activities. Crude extracts prepared via solid-state and submerged-state fermentation were tested for their effects on extracellular matrix mineralization in vitro and bone growth in zebrafish larvae, and for their activity against the respiratory syncytial virus (RSV) and herpes simplex virus type 2 (HSV-2). Several extracts exhibited significant mineralogenic and osteogenic activities, with Aspergillus jensenii MUT6581 and Cladosporium halotolerans MUT6558 being the most performing ones. Antiviral assays identified extracts from A. jensenii MUT6581 and Bjerkandera adusta MUT6589 as effective against RSV and HSV-2 at different extents, with no cytotoxic effect. Although chemical profiling of A. jensenii MUT6581 extract led to the isolation of decumbenones A and B, they did not reproduce the observed bioactivities, suggesting the involvement of other active compounds or synergistic effects. These results highlight the plastisphere as a valuable resource for novel bioactive compounds and suggest the need for further fractionation and characterization to identify the molecules responsible for these promising activities.
- Circulating small non-coding RNAs provide new insights into vitamin K nutrition and reproductive physiology in teleost fishPublication . I, Fernández; Fernandes, Jorge M. O.; Roberto, Vânia; Kopp, Martina; Oliveira, Catarina; Riesco, Marta F.; Dias, Jorge; Cox, Cymon J.; Leonor Cancela, M.; Cabrita, Elsa; Gavaia, PauloBackground: Vitamin K (VK) is a fat-soluble vitamin known for its essential role in blood coagulation, but also on other biological processes (e.g. reproduction, brain and bone development) have been recently suggested. Nevertheless, the molecular mechanisms behind its particular function on reproduction are not yet fully understood. Methods: The potential role of VK on reproduction through nutritional supplementation in Senegalese sole (Solea senegalensis) was assessed by gonadal maturation and 11-ketosterone, testosterone and estriol plasma levels when fed with control or VK supplemented (1250 mg kg(-1) of VK,) diets along a six month trial. At the end, sperm production and quality (viability and DNA fragmentation) were evaluated. Circulating small non-coding RNAs (sncRNAs) in blood plasma from males were also studied through RNA-Seq. Results: Fish fed with dietary VK supplementation had increased testosterone levels and lower sperm DNA fragmentation. SncRNAs from blood plasma were found differentially expressed when nutritional and sperm quality conditions were compared. PiR-675//676//4794//5462 and piR-74614 were found up-regulated in males fed with dietary VK supplementation. Let-7g, let-7e(18nt), let-7a-1, let-7a-3//7a-2//7a-1, let-7e(23nt) and piR-675//676//4794//5462 were found to be up-regulated and miR-146a and miR-146a-1//146a-2//146a-3 down-regulated when fish with low and high sperm DNA fragmentation were compared. Bioinformatic analyses of predicted mRNAs targeted by sncRNAs revealed the potential underlying pathways. Conclusions: VK supplementation improves fish gonad maturation and sperm quality, suggesting an unexpected and complex regulation of the nutritional status and reproductive performance through circulating sncRNAs. General significance: The use of circulating sncRNAs as reliable and less-invasive physiological biomarkers in fish nutrition and reproduction has been unveiled.
- Comparison of different microalgae biomass typologies used in rotifers enrichment for zebrafish (Danio rerio) larvae nutritionPublication . de Castro, Daniela; Castaldi, Matthew; Martins, Gil; Santos, Tamara; Pereira, Hugo; Diogo, Patrícia; Varela, João; Gavaia, Paulo; Shivendra KumarThe use of enriched rotifers with industrially produced microalgae represents a valuable tool for the enhancement of zebrafishlarval nutrition and increased biological performance. Currently, a monoculture of microalgal species (Nannochloropsis sp.) inform of liquid paste is routinely used for rotifers enrichment for zebrafish larvae feeding; however, the most adequate typology (i.e.,paste or freeze-dried) of the industrially produced microalgal biomass is still controversial. This work aimed to compare the effectsof rotifers enriched with three different industrially produced microalgae species (i.e., Nannochloropsis oceanica, Tetraselmis chui,and Tisochrysis lutea) using paste and freeze-dried powder. Enriched rotifers were provided as feed during larval growth and theimpact on growth and survival was evaluated. The use of enriched rotifers with both paste or freeze-dried microalgae improvedgrowth compared to larvae fed exclusively with commercial microdiet. Larvae fed rotifers enriched with N. oceanica and T. chuiattained higher weight and length both at 15 and 30 days postfertilization (dpf ), while the use of microalgae in paste contributed togreater larvae lengths when compared to freeze-dried. The experimental results in this study revealed that N. oceanica and T. chuiin paste are the most suitable microalgae forms to be used in zebrafish larvae nutrition and in the improvement of enrichmentmethodologies for rotifers.
- Cryoprotectants synergy improve zebrafish sperm cryopreservation and offspring skeletogenesisPublication . Diogo, Patricia; Martins, Gil; Nogueira, Rita; Marreiros, Ana; Gavaia, Paulo; Cabrita, ElsaThe synergy obtained by the combination of cryoprotectants is a successful strategy that can be beneficial on the optimization of zebrafish sperm cryopreservation. Recently, a protocol was established for this species using an electric ultrafreezer (-150 degrees C) performing cooling rate (-66 degrees C/min) and storage within one step. The ultimate objective of sperm cryopreservation is to generate healthy offspring. Therefore, the objective of this study was to select the most adequate cryoprotectant combination, for the previously established protocol, that generate high quality offspring with normal skeletogenesis. Among the permeating cryoprotectant concentrations studied 12.5% and 15% of N,N-dimethylformamide (DMF) yielded high post-thaw sperm quality and hatching rates. For these two concentrations, the presence of bovine serum albumin (10 mg/mL), egg yolk (10%), glycine (30 mM) and bicine (50 mM) was evaluated for post-thaw sperm motility, viability, in vitro fertilization success and offspring skeletal development (30 days post fertilization). Higher concentration of permeating cryoprotectant (15%) decreased the incidence of deformed arches and severe skeletal malformations, which suggests higher capacity to protect the cell against cold stress and DNA damage. Extender containing 15% DMF with Ctrl, Bicine and egg yolk were the non-permeating cryoprotectants with higher post-thaw quality. The use of these compounds results in a reduction in vertebral fusions, compressions and severity of skeletal malformations in the offspring. Therefore, these extender compositions are beneficial for the quality of zebrafish offspring sired by cryopreserved sperm with 66 degrees C/min freezing rate. To the best of our knowledge, this is the first report on skeletal development of the offspring sired by cryopreserved sperm performed with different freezing media compositions in zebrafish.
- Dietary beauvericin and enniatin B exposure cause different adverse health effects in farmed Atlantic salmonPublication . Berntssen, M. H. G.; Fjeldal, P. G.; Gavaia, Paulo; Laizé, Vincent; Hamre, K.; Donald, C. E.; Jakobsen, J. V.; Omdal, Å.; Søderstrøm, S.; Lie, K. K.The extensive use of plant ingredients in novel aquafeeds have introduced mycotoxins to the farming of seafood. The emerging enniatin B (ENNB) and beauvericin (BEA) mycotoxins have been found in the novel aquafeeds and farmed fish. Little is known about the potential toxicity of ENNs and BEA in farmed fish and their feed-to-organ transfer. Atlantic salmon (Salmo salar) presmolt (75.3 +/- 8.10 g) were fed four graded levels of spiked chemical pure ENNB or BEA feeds for three months, in triplicate tanks. Organismal adverse health end-point assessment included intestinal function (protein digestibility), disturbed hematology (red blood cell formation), bone formation (spinal deformity), overall energy use (feed utilization), and lipid oxidative status (vitamin E). Both dietary BEA and ENNB had a low ( liver > brain > muscle), with a higher transfer for ENNB compared to BEA. BEA caused a growth reduction combined with a decreased protein digestion and feed conversion rate-ENNB caused a stunted growth, unrelated to feed utilization capacity. In addition, ENNB caused anemia while BEA gave an oxidative stress response. Lower bench-mark dose regression assessment showed that high background levels of ENNB in commercial salmon feed could pose a risk for animal health, but not in the case of BEA.
- Distinguishing the effects of Water volumes versus stocking densities on the skeletal quality during the Pre-Ongrowing Phase of Gilthead Seabream (Sparus aurata)Publication . Dellacqua, Zachary; Di Biagio, Claudia; Costa, Corrado; Pousão-Ferreira, Pedro; Ribeiro, Laura; Barata, Marisa; Gavaia, Paulo; Mattei, Francesco; Fabris, Andrea; Izquierdo, Marisol; Boglione, ClaraGilthead seabream (Sparus aurata) production is a highly valued aquaculture industry in Europe. The presence of skeletal deformities in farmed gilthead seabream represents a major bottleneck for the industry leading to economic losses, negative impacts on the consumers’ perception of aquaculture, and animal welfare issues for the fish. Although past work has primarily focused on the hatchery phase to reduce the incidence of skeletal anomalies, this work targets the successive preongrowing phase in which more severe anomalies affecting the external shape often arise. This work aimed to test the effects of: (i) larger and smaller tank volumes, stocked at the same density; and (ii) higher and lower stocking densities maintained in the same water volume, on the skeleton of gilthead seabream fingerlings reared for ~63 days at a pilot scale. Experimental rearing was conducted with gilthead seabream juveniles (~6.7 ± 2.5 g), which were selected as ‘non-deformed’ based on external inspection, stocked at three different densities (Low Density (LD): 5 kg/m3 ; Medium Density (MD): 10 kg/m3 ; High Density (HD): 20 kg/m3 ) in both 500 L and 1000 L tanks. Gilthead seabream were sampled for growth performance and radiographed to assess the skeletal elements at the beginning and end of the experimental trial. Results revealed that (i) LD fish were significantly longer than HD fish, although there were no differences in final weights, regardless of the water volume; (ii) an increase in the prevalence of seabream exhibiting cranial and vertebral axis anomalies was found to be associated with increased density. These results suggest that farmers can significantly reduce the presence of some cranial and axis anomalies affecting pre-ongrown gilthead seabream by reducing the stocking density.