Search Results (220)

Marine lectins function as pattern recognition receptors in innate immunity through carbohydrate-binding mechanisms. However, mechanistic evidence detailing intracellular signaling cascades (e.g., MAPK/NF-κB/JAK-STAT activation linked to defined cytokine outputs) remains taxonomically uneven. Bivalve mollusks—particularly the Mytilectin family—represent the most extensively characterized group, whereas lectins from other marine phyla (echinoderms, cnidarians, fish, algae) have been studied primarily for structural and glycan-binding properties alongside phenotypic antimicrobial outcomes. Signaling-level resolution in native immune-cell contexts, while present in some cases, remains comparatively limited. This review synthesizes mechanistic insights dominated by bivalve-derived lectins, while integrating cross-taxa comparisons at evidence-supported levels. Specific bivalve lectins induce macrophage activation and pro-inflammatory cytokine production through reactive oxygen species-dependent activation of key signaling pathways including MAPK, NF-κB, and JAK-STAT cascades. These lectins exhibit context-dependent properties, promoting inflammatory responses in resting cells while inducing endotoxin tolerance in pre-activated macrophages through epigenetic reprogramming. Functional outcomes include broad-spectrum antiviral activity through viral envelope glycoprotein binding, anti-inflammatory effects in pain models, and cancer-associated immune responses through tumor glycan recognition and macrophage polarization. Critical gaps include uncharacterized effects on adaptive immunity, limited understanding of dendritic cell and natural killer cell interactions, and incomplete evaluation of cancer immunotherapy potential. Future research should prioritize mechanistic characterization of marine lectin-based immunotherapeutics. Full article

The family Flaviviridae has been expanded to include the highly divergent flavi-like viruses into three new families, Flaviviridae, Pestiviridae, and Hepaciviridae, in the order Amarillovirales. Classical flavivirids are small, enveloped viruses with positive-sense ssRNA genomes lacking a 3′ poly(A) tail and ~9.0–13.0 kb in length, with a single open reading frame (ORF) encoding structural proteins at the N-terminus and nonstructural proteins at the C-terminus. Members infect a wide range of mammals, birds, and insects, and many are host-specific and pathogenic. Although the RNA-directed RNA polymerase (RdRP) gene sequences of the flavi-like viruses group phylogenetically with those of classical flavivirids, flavi-like viruses often encode larger polyproteins and possess substantially longer genomes of up to ~40 kb, and some have a 3′ poly(A) tail. Their host range extends across the whole animal kingdom and angiosperm plants. This review describes the reported flavi-like viruses of aquatic animals, providing a meaningful update on all three new families in Amarillovirales that have been discovered using metagenomics in fish, crustaceans, mollusks, and echinoderms. These amarilloviruses include pathogenic viruses of aquatic animals, such as Cyclopterus lumpus virus (CLuV) detected in moribund lumpfish, and infectious precocity virus (IPV) found in iron prawn syndrome (IPS)-affected farmed giant freshwater prawns. Full article

Echinoderms are marine invertebrates that play important roles in structuring marine benthic ecosystems. DNA barcoding has become a valuable tool for species identification; however, reference DNA barcode libraries for echinoderms remain incomplete. This study aims to: (i) develop a COI-5′ reference dataset for echinoderms from Vietnam by integrating DNA barcodes with morphological data; (ii) evaluate species resolution and barcode gaps using multiple analytical approaches; (iii) assess the consistency of species assignments from BOLD and GenBank for echinoderms collected in Vietnam; (iv) make barcode data publicly available to support global reference database development. Thirty-two echinoderm specimens representing 16 species were analyzed for COI-5′ sequences, and BLAST assignments were highly concordant with those from GenBank and BOLD. Integrative validation confirmed that all taxa were monophyletic in the Neighbor Joining Tree, formed single OTUs in Cluster Sequences, and exhibited clear barcode gaps greater than 3% to the nearest-neighbor species. These results provided species-level resolution for 75% and genus-level resolution for 90% of the records. The dataset, spanning four classes, eight orders, and eleven families, enhances barcode coverage and contributes records (ProcessIDs. BINs; GenBank accessions) to public repositories. This study delivers the first curated COI-5′ reference library, supporting regional baselines for taxonomy, conservation, and biodiversity assessment. Full article

The Isles of Scilly are an archipelago of islands in the far southwest of the UK which contain numerous beds of wild bivalve molluscs which are recreationally harvested for local consumption. However, the islands have never previously been assessed for the presence of harmful algae and their shellfish toxin metabolites which can cause serious human health impacts. This study sought to address these knowledge gaps through the analysis of seawater and shellfish tissues for microalgae and toxins utilizing portable and lab-based microscopy, nanopore sequencing, chemical analysis and immunoassay kits. The study design was affected by the national COVID-19 lockdown which enforced implementation of citizen-led sampling and in-field microscopy. Microscopy and sequencing approaches led to the confirmation of multiple HAB species of concern, including those potentially responsible for production of neurotoxic and diarrhetic shellfish toxins. A portable microscope was successfully utilized in the field for recognition of microalgae and for early warning of potential shellfish toxicity events. Chemical analysis of cockle, clam and mussel samples confirmed the detection of paralytic, diarrhetic and amnesic shellfish toxins, with an unusual okadaic acid group toxin profile reaching a maximum toxicity of approximately half the regulatory limit as defined by EU law. The Sensoreal Alert Lateral Flow Assay was used to screen and highlight samples containing higher concentrations of DSP toxins. Furthermore, Tetrodotoxin was detected for the first time in the UK in cockle and grooved carpet shells. Multiple saxitoxin analogues were also detected in two echinoderm species, with this providing the first ever report of paralytic shellfish toxins in the spiny starfish, Marthasterias glacialis. The toxin profiles in the two species varied significantly with a dominance of GTX4 in Luidia ciliaris as opposed to a dominance of STX in Marthasterias glacialis. Overall, the study showed that a multi-method assessment of a previously unexplored region within the UK territory contained microalgae and toxins of concern to human health, and that a citizen-led programme could be instigated using portable microscopy and rapid toxin testing to assess the early warning for potentially harmful microalgae and toxins in the region, with confirmatory analysis being conducted to establish actual levels of risk for local consumers of seafood. Full article

This review analyzes current research on short-term culture of sea urchin from barrens through formulated feed, addressing the need for sustainable aquaculture practices and ecological restoration of kelp forests. We compare the results of multiple studies to identify the optimal feed composition to induce gonad growth and coloration. Our analysis suggests that macroalgae are the best feed ingredients to improve gonad growth and coloration; however, environmental and economic challenges persist in expanding sea urchin production with these types of ingredients. Plant-based protein sources like soy have emerged as a potential cost-effective alternative to fish products; nevertheless, the presence of antinutritional factors in soy products limits their inclusion in formulated feed. Regarding the composition and amount of lipids, we found that they are critical macronutrients in gonad development. The review also explores the potential of sea urchin aquaculture in mitigating urchin barrens and restoring kelp forests, highlighting the interplay between ecological and economic factors. We identify key knowledge gaps and propose future research directions, including large-scale economic viability assessments, novel feed additives, and integrated multitrophic aquaculture systems. These findings have significant implications for developing sustainable and economically viable sea urchin aquaculture, potentially transforming urchin barrens into productive ecosystems while meeting market demand for roe. Full article

The detection of tetrodotoxins (TTXs) in European shellfish led the European Union to request a risk assessment from the European Food Safety Authority (EFSA). EFSA set a reference limit of 44 µg TTX equivalents kg⁻¹ and called for more data on TTX occurrence, especially in gastropods, which can accumulate in TTXs but remain poorly studied. Recently, preliminary monitoring has revealed the recurrent presence of TTXs in mussels in three areas along the North–Central Adriatic coast of Italy, while research on non-bivalve organisms has not yet been carried out. This study presents a preliminary survey, conducted from January 2023 to March 2025, on the presence of TTXs in gastropods, echinoderms, and arthropods collected from this area. A method in Hydrophilic Interaction Liquid Chromatography coupled with tandem Mass Spectrometry (HILIC-MS/MS) for detecting TTXs in bivalve mollusks was first tested through an international proficiency test, then optimized for the other invertebrates, the object of this study. TTX levels in all gastropods and arthropod samples were undetectable, while traces (~5 µg kg⁻¹) were found in one echinoderm sample (Paracentrotus lividus), marking the first reported occurrence of TTX in this species. Sea urchins are widely consumed in Italy; therefore, this finding is of particular importance from a public health perspective and deserves further investigation. Some gastropod genera or species sampled (e.g., Nassarius, Rapana venosa) have been identified as TTX carriers in other regions; therefore, the negative results obtained in this study may be related to seasonal or geographic variability. These results provide valuable data to EFSA’s call for monitoring emerging risks, particularly as climate change may increase TTX prevalence in European waters as well as worldwide. Full article

Nicotinic acid adenine dinucleotide phosphate (NAADP) is a second messenger that stimulates intracellular Ca²⁺ release in both mammalian cells and echinoderm egg homogenates. A NAADP linked covalently to a stable long-wavelength fluorescent dye would be a useful probe with which to characterize NAADP–receptor interactions in solution and potentially to determine intracellular-binding localization. We report the synthesis of a BODIPY-NAADP covalent conjugate made through linking the carboxyl group of BODIPY FL to the primary amino group of 5-(3-aminopropyl)-NAADP through amide bond formation. The starting pyridine dinucleotide analog, 5-(3-aminopropyl)-NAADP was available through enzyme-catalyzed base exchange between NADP and a substituted nicotinic acid analog. The resulting 5-BODIPY-NAADP conjugate was purified to homogeneity using ion-exchange chromatography, was produced in milligram quantities, and its spectroscopic properties were characterized. Full article

Mutable collagenous tissue (MCT) is a type of connective tissue that is characterized by its capacity to undergo rapid, nervously mediated changes in mechanical properties. In terms of both the magnitude of these changes and the timescale within which they occur (less than one second to a few minutes), this tissue appears to be unique to the phylum Echinodermata and, as it is ubiquitous in all five extant echinoderm classes, it represents one of the four major defining features of the phylum, together with pentaradial symmetry, endoskeletal stereom (calcite meshwork), and the water vascular system. MCT has been the subject of intensive scientific investigation for over 50 years. The primary aim of this contribution is to provide a comprehensive and definitive survey of the current state of knowledge of this remarkable tissue. After outlining the history of the scientific investigation of MCT, we review current information on its anatomical distribution, organization at the histological, ultrastructural and molecular levels, and physiology—focusing on its mechanical behavior and the regulation of this behavior; its significance for echinoderm biology, including pathology; and biomedical and other applications that exploit MCT-derived components or biological principles. We conclude by drawing attention to more serious deficiencies in the current knowledge base and suggesting how these should be rectified. Full article

Centrostephanus longispinus (Philippi, 1845) is a sea urchin widely distributed across the tropical and temperate Atlantic Ocean (including the Caribbean) and Mediterranean Sea. Although it is present along the Alboran Sea coastline (Western Mediterranean), it is generally considered rare and is listed under conservation and protection lists and conventions due to fragmented populations threatened by seabed degradation. This study provides the first density and size distribution data for this echinoid in the circalittoral and bathyal bottoms of the Alboran Sea, aiming to relate its presence to seabed features, environmental variables, and human pressures. A series of 131 (62 ROV and 69 TASIFE transects) underwater image transects were collected during CIRCAESAL expeditions (2021, 2023, 2024) using a ROV and a photogrammetric sledge from infralittoral to bathyal bottoms (17–856 m depth). Images were processed with OFOP software to quantify and classify individuals by size classes, depth, substrate, seafloor roughness, micro-habitat, and coverage of key benthic structuring species. A total of 524 individuals of C. longispinus were detected in 13 transects, with the highest densities recorded at 48–100 m depths in rough, rocky substrates with crevices and a moderate to low coverage of key benthic structuring species. Differences in habitat use were also observed across depth strata: individuals in shallower zones tend to remain hidden within crevices and structurally complex substrates, displaying a more cryptic behaviour, whereas those in deeper strata rely less on refuge and occupy less complex habitats. The largest aggregations occurred near the Guadiaro Canyon, outside the “Estrecho Oriental” Special Area of Conservation (SAC), suggesting this area may serve as a population reservoir deserving conservation. Despite these findings, ecological knowledge of C. longispinus remains limited, and future studies should improve the knowledge gaps, particularly in the eastern and southern Alboran Sea. Full article

This study investigated whether marine toxin poisonings reported to U.S. Poison Centers changed during the height of the pandemic period (April 2020 to December 2021). The National Poison Data System was queried for single-substance human exposure calls between 1 January 2000 and 31 March 2022 pertaining to ichthyosarcotoxins. Incidence rate ratios for exposure calls were calculated using mixed-effects negative binomial regression. Call counts were aggregated by year and regressed on a binary indicator for occurrence during pandemic restrictions. During the peak pandemic period, exposure calls decreased for several toxins: ciguatera poisoning: 0.57 (0.43, 0.76); clupeotoxic fish poisoning: 0.12 (0.04, 0.39); diarrhetic shellfish poisoning: 0.28 (0.16, 0.49); paralytic shellfish poisoning: 0.23 (0.17, 0.33); scombroid fish poisoning: 0.46 (0.36, 0.57). However, palytoxin poisoning (1.94 (1.32, 2.84)) and tetrodotoxin poisoning (1.73 (1.46, 2.04)) exposure calls appear to have increased. All results were Bonferroni-significant (p ≤ 0.0009). Sensitivity analyses suggest the PLTX increase began prior to pandemic restrictions, whereas the TTX increase appeared to be directly associated with the restrictions. Both men and women reported increases in TTX exposure calls. The TTX increase could be associated with potentially increased participation in outdoor activities, as TTX exposures are linked to amphibia, echinoderms, fish, and mollusks, among other animals. Full article

This study evaluated the performance of a recirculating aquaculture system (RAS) integrated with macroalgae (Ulva ohnoi) cultivation and sea urchin (Paracentrotus lividus) feeding, in a multi-trophic aquaculture approach. This system aimed to enhance sustainability through water bioremediation by macroalgae and valorization of the algal biomass as echinoderms feed. Over a 180-day trial, biomass production of U. ohnoi remained stable, with daily growth rates ranging from 7.4 to 24.4%. Statistical analyses (PCA and GAM) indicated no significant linear or non-linear relationship between macroalgae growth and environmental parameters (temperature, radiation, photoperiod). A theoretical estimate of nutrient production showed fairly stable values that do not statistically explain biomass production variation, highlighting the species’ adaptability. Sea urchins fed with fresh U. ohnoi showed regular growth, supporting the nutritional suitability of this macroalgae. For fish (Sparus aurata), no significant differences in growth or feed conversion ratio were observed between systems with and without algae. Parasitological monitoring revealed lower parasite loads and egg deposition in tanks in recirculation with U. ohnoi during certain periods, suggesting a potential role of macroalgae in reducing monogenean propagation. These findings underscore the feasibility of integrating Ulva cultivation into RAS, contributing to circular aquaculture models with improved sustainability and resource efficiency. Full article

We studied the feeding habits of the common eagle ray (Myliobatis aquila) in the shallow northern Adriatic Sea. Altogether we analysed the contents of 122 stomachs of specimens caught as by-catch in the Gulf of Trieste and along the west Istrian coast. Shelled molluscs (N% = 75.17), mainly bivalves and gastropods, were the most prominent prey categories, while crustaceans, sipunculids, echinoderms and polychaets (N% < 10) represented considerably smaller numbers. With increasing size (and age) the eagle rays tend to become more experienced in preying molluscs and specialized to this prey category. The obtained results are in general in agreement with the limited existing reports on the diet of the common eagle ray in the Mediterranean Sea and adjacent areas. Full article

Sea urchins (Echinoidea) are marine echinoderms commonly consumed as seafood in East Asia. To date, various metabolic components of sea urchins have been analyzed, and their health benefits for humans have also been attracting attention. Lipids are the major biomolecules present in sea urchins. However, the comprehensive lipid profiling of sea urchins is limited. In this study, we aimed to perform the comprehensive lipid profiling of six types of sea urchins using liquid chromatography–mass spectrometry (LC/MS). The application of untargeted lipidomics led to the identification of 281 lipid molecular species in six varieties of fresh sea urchin gonads. Each lipid metabolite was identified based on its retention time and MS/MS fragmentation pattern. The results of the analysis showed the highest abundance of lipid percentage in Kitamurasakiuni (14.3%), followed by Hokuyobafununi (12.4%). In all the analyzed sea urchins, glycerolipids such as triacylglycerols were found to be the most abundant lipid components. Multivariate analysis revealed that Murasakiuni showed a different lipid profile from the other types. Interestingly, the polyunsaturated fatty acid to saturated fatty acid ratios and health-related nutritional indices factors were found to be higher in Hokuyobafununi compared to other varieties. The ω-3 fatty acids, such as docosapentaenoic acid (FA 22:6) and eicosapentaenoic acid (FA 20:5), were also abundant in Hokuyobafununi. Lipids such as ether and N-acyl-type lysophosphatidylethanolamines were detected for the first time in sea urchins. This study highlights the nutritional significance of sea urchins and their potential use in the development of functional foods. Full article

Sea urchins, Echinoidea, are widely known for their defensive spines and pedicellariae, with some species having co-evolved venom in conjunction with those appendages. Despite this, their venomous arsenal remains poorly understood. Research has predominately focused on pedicellariae venom, while the spines have been largely neglected within studies. This review consolidates current knowledge of the venom systems (spines and pedicellariae) of sea urchins, focusing on the morphology, known venom components, and their functional effects. While early studies have established the bioactivity of crude extracts and fractions, along with the partial characterisation of some toxins, most of these studies are outdated and were conducted with very basic methodologies. Modern venomics presents an opportunity to meet this challenge, enabling development of a comprehensive database on venomous urchins and their toxins. This advancement will facilitate research into targeted early treatments and therapies for victims of sea urchin stings, ultimately improving health outcomes and enhancing our scientific understanding of venom toxins and their broader implications for human health and bioinnovation. Full article

The work aimed to investigate the presence of pharmaceutical compounds from the anti-inflammatory class in seawater from the Romanian Black Sea coast and to assess the ecological risk of these substances on the most sensitive organisms. Using the solid-phase extraction technique (SPE) followed by liquid chromatography separation and mass spectrometry detection (LC-MS/MS) of the compounds, the concentrations of these contaminants in selected seawater samples were determined. Ibuprofen was the most commonly detected compound with a frequency of 42.9%, followed by ketoprofen at 31.0.%, diclofenac at 23.8%, and naproxen at 21.4%. The maximum concentrations of pharmaceutical products varied between 13.4 ng/L ketoprofen and 13,575 ng/L caffeine. The order of decreasing maximum concentrations of pharmaceutical compounds in the water of the Black Sea was CAF > IBU > NAP > DIC > KET. The dominant and ubiquitous compound that was determined with the maximum concentration values was caffeine. Strong correlations were observed between three compounds (naproxen: diclofenac, diclofenac: ketoprofen) suggesting the same pollution source. Through the ecological risk assessment, it was observed that both caffeine and ibuprofen can generate high ecological risks for some echinoderms, crustaceans, and fish. Full article