Bacterial degradation of ctenophore Mnemiopsis leidyi organic matter.

Blooms of gelatinous zooplankton, an important source of protein-rich biomass in coastal waters, often collapse rapidly, releasing large amounts of labile detrital organic matter (OM) into the surrounding water. Although these blooms have the potential to cause major perturbations in the marine ecosystem, their effects on the microbial community and hence on the biogeochemical cycles have yet to be elucidated. We conducted microcosm experiments simulating the scenario experienced by coastal bacterial communities after the decay of a ctenophore (Mnemiopsis leidyi) bloom in the northern Adriatic Sea. Within 24 h, a rapid response of bacterial communities to the M. leidyi OM was observed, characterized by elevated bacterial biomass production and respiration rates. However, compared to our previous microcosm study of jellyfish (Aurelia aurita s.l.), M. leidyi OM degradation was characterized by significantly lower bacterial growth efficiency, meaning that the carbon stored in the OM was mostly respired. Combined metagenomic and metaproteomic analysis indicated that the degradation activity was mainly performed by Pseudoalteromonas, producing a large amount of proteolytic extracellular enzymes and exhibiting high metabolic activity. Interestingly, the reconstructed metagenome-assembled genome (MAG) of Pseudoalteromonas phenolica was almost identical (average nucleotide identity >99%) to the MAG previously reconstructed in our A. aurita microcosm study, despite the fundamental genetic and biochemical differences of the two gelatinous zooplankton species. Taken together, our data suggest that blooms of different gelatinous zooplankton are likely triggering a consistent response from natural bacterial communities, with specific bacterial lineages driving the remineralization of the gelatinous OM.IMPORTANCEJellyfish blooms are increasingly becoming a recurring seasonal event in marine ecosystems, characterized by a rapid build-up of gelatinous biomass that collapses rapidly. Although these blooms have the potential to cause major perturbations, their impact on marine microbial communities is largely unknown. We conducted an incubation experiment simulating a bloom of the ctenophore Mnemiopsis leidyi in the Northern Adriatic, where we investigated the bacterial response to the gelatinous biomass. We found that the bacterial communities actively degraded the gelatinous organic matter, and overall showed a striking similarity to the dynamics previously observed after a simulated bloom of the jellyfish Aurelia aurita s.l. In both cases, we found that a single bacterial species, Pseudoalteromonas phenolica, was responsible for most of the degradation activity. This suggests that blooms of different jellyfish are likely to trigger a consistent response from natural bacterial communities, with specific bacterial species driving the remineralization of gelatinous biomass.

The branched mitochondrial respiratory chain from the jellyfish Stomolophus sp2 as a probable adaptive response to environmental changes.

During their long evolutionary history, jellyfish have faced changes in multiple environmental factors, to which they may selectively fix adaptations, allowing some species to survive and inhabit diverse environments. Previous findings have confirmed the jellyfish's ability to synthesize large ATP amounts, mainly produced by mitochondria, in response to environmental challenges. This study characterized the respiratory chain from the mitochondria of the jellyfish Stomolophus sp2 (previously misidentified as Stomolophus meleagris). The in-gel activity from isolated jellyfish mitochondria confirmed that the mitochondrial respiratory chain contains the four canonical complexes I to IV and F0F1-ATP synthase. Specific additional activity bands, immunodetection, and mass spectrometry identification confirmed the occurrence of four alternative enzymes integrated into a branched mitochondrial respiratory chain of Stomolophus sp2: an alternative oxidase and three dehydrogenases (two NADH type II enzymes and a mitochondrial glycerol-3-phosphate dehydrogenase). The analysis of each transcript sequence, their phylogenetic relationships, and each protein's predicted models confirmed the mitochondrial alternative enzymes' identity and specific characteristics. Although no statistical differences were found among the mean values of transcript abundance of each enzyme in the transcriptomes of jellyfish exposed to three different temperatures, it was confirmed that each gene was expressed at all tested conditions. These first-time reported enzymes in cnidarians suggest the adaptative ability of jellyfish's mitochondria to display rapid metabolic responses, as previously described, to maintain energetic homeostasis and face temperature variations due to climate change.

Protective Effects of a Jellyfish-Derived Thioredoxin Fused with Cell-Penetrating Peptide TAT-PTD on H2O2-Induced Oxidative Damage.

Thioredoxin (Trx) plays a critical role in maintaining redox balance in various cells and exhibits anti-oxidative, anti-apoptotic, and anti-inflammatory effects. However, whether exogenous Trx can inhibit intracellular oxidative damage has not been investigated. In previous study, we have identified a novel Trx from the jellyfish Cyanea capillata, named CcTrx1, and confirmed its antioxidant activities in vitro. Here, we obtained a recombinant protein, PTD-CcTrx1, which is a fusion of CcTrx1 and protein transduction domain (PTD) of HIV TAT protein. The transmembrane ability and antioxidant activities of PTD-CcTrx1, and its protective effects against H2O2-induced oxidative damage in HaCaT cells were also detected. Our results revealed that PTD-CcTrx1 exhibited specific transmembrane ability and antioxidant activities, and it could significantly attenuate the intracellular oxidative stress, inhibit H2O2-induced apoptosis, and protect HaCaT cells from oxidative damage. The present study provides critical evidence for application of PTD-CcTrx1 as a novel antioxidant to treat skin oxidative damage in the future.

Investigation of Best Practices for Venom Toxin Purification in Jellyfish towards Functional Characterisation.

The relative lack of marine venom pharmaceuticals can be anecdotally attributed to difficulties in working with venomous marine animals, including how to maintain venom bioactivity during extraction and purification. The primary aim of this systematic literature review was to examine the key factors for consideration when extracting and purifying jellyfish venom toxins to maximise their effectiveness in bioassays towards the characterisation of a single toxin.An up-to-date database of 119 peer-reviewed research articles was established for all purified and semi-purified venoms across all jellyfish, including their level of purification, LD50, and the types of experimental toxicity bioassay used (e.g., whole animal and cell lines). We report that, of the toxins successfully purified across all jellyfish, the class Cubozoa (i.e., Chironex fleckeri and Carybdea rastoni) was most highly represented, followed by Scyphozoa and Hydrozoa. We outline the best practices for maintaining jellyfish venom bioactivity, including strict thermal management, using the "autolysis" extraction method and two-step liquid chromatography purification involving size exclusion chromatography. To date, the box jellyfish C. fleckeri has been the most effective jellyfish venom model with the most referenced extraction methods and the most isolated toxins, including CfTX-A/B. In summary, this review can be used as a resource for the efficient extraction, purification, and identification of jellyfish venom toxins.

Localization of Multiple Jellyfish Toxins Shows Specificity for Functionally Distinct Polyps and Nematocyst Types in a Colonial Hydrozoan.

Hydractinia symbiolongicarpus is a colonial hydrozoan that displays a division of labor through morphologically distinct and functionally specialized polyp types. As with all cnidarians, their venoms are housed in nematocysts, which are scattered across an individual. Here, we investigate the spatial distribution of a specific protein family, jellyfish toxins, in which multiple paralogs are differentially expressed across the functionally specialized polyps. Jellyfish toxins (JFTs) are known pore-forming toxins in the venoms of medically relevant species such as box jellyfish (class Cubozoa), but their role in other medusozoan venoms is less clear. Utilizing a publicly available single-cell dataset, we confirmed that four distinct H. symbiolongicarpus JFT paralogs are expressed in nematocyst-associated clusters, supporting these as true venom components in H. symbiolongicarpus. In situ hybridization and immunohistochemistry were used to localize the expression of these JFTs across the colony. These expression patterns, in conjunction with known nematocyst type distributions, suggest that two of these JFTs, HsymJFT1c-I and HsymJFT1c-II, are localized to specific types of nematocysts. We further interpret JFT expression patterns in the context of known regions of nematogenesis and differential rates of nematocyst turnover. Overall, we show that JFT expression patterns in H. symbiolongicarpus are consistent with the subfunctionalization of JFT paralogs across a partitioned venom system within the colony, such that each JFT is expressed within a specific set of functionally distinct polyp types and, in some cases, specific nematocyst types.

Jellyfish Polysaccharides for Wound Healing Applications.

Jellyfishes are considered a new potential resource in food, pharmaceutical and biomedical industries. In these latter cases, they are studied as source of active principles but are also exploited to produce marine collagen. In the present work, jellyfish skin polysaccharides (JSP) with glycosaminoglycan (GAG) features were extracted from Rhizostoma pulmo, a main blooming species of Mediterranean Sea, massively augmented by climate leaded "jellyfishication" of the sea. Two main fractions of R. pulmo JSP (RP-JSPs) were isolated and characterized, namely a neutral fraction (RP-JSP1) and a sulphate rich, negatively charged fraction (RP-JSP2). The two fractions have average molecular weights of 121 kDa and 590 kDa, respectively. Their sugar composition was evaluated through LC-MS analysis and the result confirmed the presence of typical GAG saccharides, such as glucose, galactose, glucosamine and galactosamine. Their use as promoters of wound healing was evaluated through in vitro scratch assay on murine fibroblast cell line (BALB/3T3 clone A31) and human keratinocytes (HaCaT). Both RP-JSPs demonstrated an effective confluency rate activity leading to 80% of scratch repair in two days, promoting both cell migration and proliferation. Additionally, RP-JSPs exerted a substantial protection from oxidative stress, resulting in improved viability of treated fibroblasts exposed to H2O2. The isolated GAG-like polysaccharides appear promising as functional component for biomedical skin treatments, as well as for future exploitation as pharmaceutical excipients.

Discovery of a novel jellyfish venom metalloproteinase inhibitor from secondary metabolites isolated from jellyfish-derived fungus Aspergillus versicolor SmT07.

The major jellyfish stings that occur in China are caused by scyphozoan Nemopilema nomurai, whose venom exhibits significant metalloproteinase activity that contributes to the toxic effects of jellyfish envenomation. Researching effective inhibitors suppressing the metalloproteinase activity of jellyfish venom represents a new attempt to cure jellyfish envenomations. In the present study, secondary metabolites produced by the jellyfish-associated fungus Aspergillus versicolor SmT07 were isolated and evaluated for their anti-proteolytic activities. Two xanthones, sterigmatocystin (JC-01) and oxisterigmatocystin C (JC-06), and four alkaloids, cottoquinazoline A (JC-02), phenazine-1-carboxylic acid (JC-03), viridicatin (JC-04) and viridicatol (JC-05), were isolated and identified. Only phenazine-1-carboxylic acid (PCA) showed significant anti-proteolytic activity of jellyfish venom assayed on azocasein, and the IC50 value was 2.16 mM. PCA also significantly inhibited fibrinogenolytic activity, protecting the Bß chain of fibrinogen from degradation when preincubated with jellyfish venom at a ratio of >1:0.6 (PCA:venom, w/w). Molecular docking with several well-characterized snake venom metalloproteinases suggested the venom metalloproteinases inhibitory property of PCA by forming complex interactions with the active site via hydrogen bonds, π-π stacking and salt bridges, which was distinct from the binding mode of batimastat. The present study represents the first study identifying natural jellyfish venom metalloproteinase inhibitors from marine natural products, which may provide an alternative to develop therapeutic agents for treating jellyfish envenomations.

Evaluating the effectiveness of drones for quantifying invasive upside-down jellyfish (Cassiopea sp.) in Lake Macquarie, Australia.

Upside-down jellyfish (Cassiopea sp.) are mostly sedentary, benthic jellyfish that have invaded estuarine ecosystems around the world. Monitoring the spread of this invasive jellyfish must contend with high spatial and temporal variability in abundance of individuals, especially around their invasion front. Here, we evaluated the utility of drones to survey invasive Cassiopea in a coastal lake on the east coast of Australia. To assess the efficacy of a drone-based methodology, we compared the densities and counts of Cassiopea from drone observations to conventional boat-based observations and evaluated cost and time efficiency of these methods. We showed that there was no significant difference in Cassiopea density measured by drones compared to boat-based methods along the same transects. However, abundance estimates of Cassiopea derived from scaling-up transect densities were over-inflated by 319% for drones and 178% for boats, compared to drone-based counts of the whole site. Although conventional boat-based survey techniques were cost-efficient in the short-term, we recommend doing whole-of-site counts using drones. This is because it provides a time-saving and precise technique for long-term monitoring of the spatio-temporally dynamic invasion front of Cassiopea in coastal lakes and other sheltered marine habitats with relatively clear water.

Nomad Jellyfish Rhopilema nomadica Venom Induces Apoptotic Cell Death and Cell Cycle Arrest in Human Hepatocellular Carcinoma HepG2 Cells.

Jellyfish venom is a rich source of bioactive proteins and peptides with various biological activities including antioxidant, antimicrobial and antitumor effects. However, the anti-proliferative activity of the crude extract of Rhopilema nomadica jellyfish venom has not been examined yet. The present study aimed at the investigation of the in vitro effect of R. nomadica venom on liver cancer cells (HepG2), breast cancer cells (MDA-MB231), human normal fibroblast (HFB4), and human normal lung cells (WI-38) proliferation by using MTT assay. The apoptotic cell death in HepG2 cells was investigated using Annexin V-FITC/PI double staining-based flow cytometry analysis, western blot analysis, and DNA fragmentation assays. R. nomadica venom displayed significant dose-dependent cytotoxicity on HepG2 cells after 48 h of treatment with IC50 value of 50 µg/mL and higher toxicity (3:5-fold change) against MDA-MB231, HFB4, and WI-38 cells. R. nomadica venom showed a prominent increase of apoptosis as revealed by cell cycle arrest at G2/M phase, upregulation of p53, BAX, and caspase-3 proteins, and the down-regulation of anti-apoptotic Bcl-2 protein and DNA fragmentation. These findings suggest that R. nomadica venom induces apoptosis in hepatocellular carcinoma cells. To the best of the authors' knowledge, this is the first scientific evidence demonstrating the induction of apoptosis and cell cycle arrest of R. nomadica jellyfish venom.

Preparation and Neutralization Efficacy of Novel Jellyfish Antivenoms against Cyanea nozakii Toxins.

Jellyfish stings are a common issue globally, particularly in coastal areas in the summer. Victims can suffer pain, itching, swelling, shock, and even death. Usually, hot water, vinegar, or alumen is used to treat the normal symptoms of a jellyfish sting. However, a specific antivenom may be an effective treatment to deal with severe jellyfish stings. Cyanea nozakii often reach a diameter of 60 cm and are responsible for hundreds of thousands of stings per year in coastal Chinese waters. However, there has been no specific C. nozakii antivenom until now, and so the development of this antivenom is very important. Herein, we collected C. nozakii antisera from tentacle extract venom immunized rabbits and purified the immunoglobulin (IgG) fraction antivenom (AntiCnTXs). Subsequently, two complete procedures to produce a refined F(ab')2 type of antivenom (F(ab')2-AntiCnTXs) and Fab type of antivenom (Fab-AntiCnTXs) by multiple optimizations and purification were established. The neutralization efficacy of these three types of antivenoms was compared and analyzed in vitro and in vivo, and the results showed that all types of antibodies displayed some neutralization effect on the lethality of C. nozakii venom toxins, with the neutralization efficacy as follows: F(ab')2-AntiCnTXs ≥ AntiCnTXs > Fab-AntiCnTXs. This study describes the preparation of novel C. nozakii jellyfish antivenom preparations towards the goal of developing a new, effective treatment for jellyfish stings.

In Vivo Analysis of the Biocompatibility and Immune Response of Jellyfish Collagen Scaffolds and its Suitability for Bone Regeneration.

Jellyfish collagen, which can be defined as "collagen type 0" due to its homogeneity to the mammalian types I, II, III, V, and IX and its batch-to-batch consistent producibility, is of special interest for different medical applications related to (bone) tissue regeneration as an alternative to mammalian collagen-based biomaterials. However, no in vivo studies regarding the induction of M1- and M2-macrophages and their time-dependent ration as well as the analysis of the bone regeneration capacity of jellyfish collagen scaffolds have been conducted until now. Thus, the goal of this study was to determine the nature of the immune response to jellyfish collagen scaffolds and their bone healing capacities. Two in vivo studies using established implantation models, i.e., the subcutaneous and the calvarian implantation model in Wistar rats, were conducted. Furthermore, specialized histological, histopathological, and histomorphometrical methods have been used. As a control biomaterial, a collagen scaffold, originating from porcine pericardium, which has already been stated as biocompatible, was used for the subcutaneous study. The results of the present study show that jellyfish collagen scaffolds are nearly completely resorbed until day 60 post implantation by stepwise integration within the subcutaneous connective tissue mediated mainly by macrophages and single multinucleated giant cells. Interestingly, the degradation process ended in a vessel rich connective tissue that is understood to be an optimal basis for tissue regeneration. The study results showed an overall weaker immune response to jellyfish collagen than to porcine pericardium matrices by the induction of significantly lower numbers of macrophages together with a more balanced occurrence of M1- and M2-macrophages. However, both collagen-based biomaterials induced balanced numbers of both macrophage subtypes, which supports their good biocompatibility. Moreover, the histomorphometrical results for the calvarial implantation of the jellyfish scaffolds revealed an average of 46.20% de novo bone formation at day 60, which was significantly higher compared to the control group. Thereby, the jellyfish collagen scaffolds induced also significantly higher numbers of anti-inflammatory macrophages within the bony implantation beds. Altogether, the results show that the jellyfish collagen scaffolds allowed for a directed integration behavior, which is assumed to be in accordance with the concept of Guided Bone Regeneration (GBR). Furthermore, the jellyfish collagen scaffolds induced a long-term anti-inflammatory macrophage response and an optimal vascularization pattern within their implant beds, thus showing excellent biocompatibility and (bone) tissue healing properties.

The effect of dealuminated jellyfish in mitigating toxicity on mice exposed to aluminum.

In the present study, the removal effect of dealuminated jellyfish on Aluminum (Al) in mice was evaluated. The results showed that the consumption of dealuminated jellyfish significantly decreased Al accumulation in the liver of mice, indicating an Al-removing effect of dealuminated jellyfish on Al-enriched mice. In addition, the effect of dealuminated jellyfish consumption on an Al-overload model was further evaluated. The result showed that the Al content in different tissues and organs of mice was significantly reduced, but it had no significant effect on the other metallic element content. These results indicated that the samples from oral administration have a certain Al-removing effect in Al-overloaded mice. Moreover, the cluster analysis of differentially expressed proteins in blood and liver showed that a high dose of dealuminated jellyfish improve the expression of amine oxidase B and enhance the effect of Al discharge.

An integrated transcriptomic and proteomic analysis reveals toxin arsenal of a novel Antarctic jellyfish Cyanea sp.

Jellyfish is a common toxic zooplankton in ocean. We successfully captured a kind of jellyfish 200 m underwater in Antarctica, and identified it as a jellyfish Cyanea sp. through morphological examination and MT-CO1 phylogenetic analysis. A total of 40,468 unigenes were harvested through transcriptome sequencing. We also successfully annotated 12,955 (32.01%) unigenes with the NR database, 10,882 (26.89%) unigenes with the SWISSPROT database, 4951 (12.23%) unigenes with the GO database, and 4901 (12.11%) unigenes with the KEGG database. In the proteomic analysis, a total of 11,159 peptides and 2630 proteins were harvested using the constructed transcriptome as the database. A number of 771 (29.31%) and 841 (31.98%) proteins were annotated against the GO and KEGG database, respectively. Moreover, a number of 29 toxic proteins matched from the 145 toxin-related unigenes were successfully screened, including 6 metalloproteinases, 4 phospholipases, 2 serine proteases, 1 serine protease inhibitor, 7 toxin-related venom and 9 other toxins. Our study is the first to identify a polar jellyfish Cyanea sp. with transcriptomics and proteomics, and these data can further serve as a public database for the identification of potential polar jellyfish-derived lead compounds feasibly functioning in the cold environment. SIGNIFICANCE: With increasing discussions on marine biodiversity and global warming, polar species have gradually become a focus for research. To the best of our knowledge, there is only one paper in pubMed about the mitochondrial genome of the Antarctic stalked jellyfish Haliclystus antarcticus Pfeffer. In this study, we captured a type of jellyfish (named BD-4) from the Southern Ocean (60°29'57" S, 52°11'44"W) on the scientific expedition ship "Xue Long" at the end of 2016. Although the samples were stored and transported by the ship at only -20 °C for more than two month, we successfully extracted the total RNA, and performed molecular species identification and combined analyses of de novo transcriptomics and proteomics. In addition to conventional bioinformatics techniques such as GO and KEGG annotation, we screened and listed toxic proteins, aligned the sequences, simulated three-dimensional structures and performed molecular phylogenetic analysis for typical components, including metalloproteinase and serine proteinase. Our study is the first to identify a polar jellyfish Cyanea sp. with de novo transcriptomics and proteomics, and these data can further serve as a public database for the identification of potential polar jellyfish-derived lead compounds.

A SLC6 transporter cloned from the lion's mane jellyfish (Cnidaria, Scyphozoa) is expressed in neurons.

In the course of recent comparative genomic studies conducted on nervous systems across the phylogeny, current thinking is leaning in favor of more heterogeneity among nervous systems than what was initially expected. The isolation and characterization of molecular components that constitute the cnidarian neuron is not only of interest to the physiologist but also, on a larger scale, to those who study the evolution of nervous systems. Understanding the function of those ancient neurons involves the identification of neurotransmitters and their precursors, the description of nutrients used by neurons for metabolic purposes and the identification of integral membrane proteins that bind to those compounds. Using a molecular cloning strategy targeting membrane proteins that are known to be present in all forms of life, we isolated a member of the solute carrier family 6 from the scyphozoan jellyfish Cyanea capillata. The phylogenetic analysis suggested that the new transporter sequence belongs to an ancestral group of the nutrient amino acid transporter subfamily and is part of a cluster of cnidarian sequences which may translocate the same substrate. We found that the jellyfish transporter is expressed in neurons of the motor nerve net of the animal. To this end, we established an in situ hybridization protocol for the tissues of C. capillata and developed a specific antibody to the jellyfish transporter. Finally, we showed that the gene that codes for the jellyfish transporter also expresses a long non-coding RNA. We hope that this research will contribute to studies that seek to understand what constitutes a neuron in species that belong to an ancient phylum.

Discovery and Characterization of a Naturally Occurring, Turn-On Yellow Fluorescent Protein Sensor for Chloride.

Fluorescent proteins have been extensively engineered and applied as optical indicators for chloride in a variety of biological contexts. Surprisingly, given the biodiversity of fluorescent proteins, a naturally occurring chloride sensor has not been reported to date. Here, we present the identification and spectroscopic characterization of the yellow fluorescent protein from the jellyfish Phialidium sp . (phiYFP), a rare example of a naturally occurring, excitation ratiometric, and turn-on fluorescent protein sensor for chloride. Our results show that chloride binding tunes the p Ka of the chromophore Y66 and shifts the equilibrium from the fluorescent phenolate form to the weakly fluorescent phenol form. The latter likely undergoes excited-state proton transfer to generate a turn-on fluorescence response that is pH-dependent. Moreover, anion selectivity and mutagenesis in the chloride binding pocket provide additional evidence for the proposed chloride sensing mechanism. Given these properties, we anticipate that phiYFP, with further engineering, could be a new tool for imaging cellular chloride dynamics.

Metabolic and oxidative stress responses of the jellyfish Cassiopea to pollution in the Gulf of Aqaba, Jordan.

Physiological responses of jellyfish to pollution are virtually overlooked. We measured the activity of two glycolytic enzymes (pyruvate kinase (PK) and lactate dehydrogenase (LDH)), lipid peroxidation (LPO), protein and chlorophyll a content in the jellyfish Cassiopea sp. from polluted and reference sites along the Gulf of Aqaba, Jordan. In jellyfish from polluted sites, low PK/LDH ratios and high LDH activity clarify their reliance on anaerobic metabolism. PK and LDH were positively correlated in the jellyfish. While medusae from polluted sites showed no signs of oxidative stress damage, protein content was significantly lower. This might suggest protein utilization for energy production needed for maintenance. Unchanged LPO in polluted sites indicates the ability of jellyfish to keep reactive oxygen species under control. Overall these results suggest that the jellyfish seems to tolerate the current levels of pollution at the studied sites and they might be anaerobically poised to live at such habitats.

Smooth muscle-like Ca2+-regulation of actin-myosin interaction in adult jellyfish striated muscle.

Cnidaria is an animal phylum, whose members probably have the most ancestral musculature. We prepared and characterized, for the first time to our knowledge, native actomyosin from the striated myoepithelium of the adult moon jelly Aurelia sp. The actomyosin contained myosin, paramyosin-like protein, Ser/Thr-kinase, actin, and two isoforms of tropomyosin, but not troponin, which is known to activate contraction dependent on intracellular Ca2+ signaling in almost all striated muscles of bilaterians. Notably, the myosin comprised striated muscle-type heavy chain and smooth muscle-type regulatory light chains. In the presence of Ca2+, the Mg-ATPase activity of actomyosin was stimulated and Ser21 of the regulatory light chain was concomitantly phosphorylated by the addition of calmodulin and myosin light chain kinase prepared from chicken smooth muscle. Collectively, these results suggest that, similar to smooth muscle, the contraction of jellyfish striated muscle is regulated by Ca2+-dependent phosphorylation of the myosin light chain.

Biphasic Scaffolds from Marine Collagens for Regeneration of Osteochondral Defects.

BACKGROUND: Collagens of marine origin are applied increasingly as alternatives to mammalian collagens in tissue engineering. The aim of the present study was to develop a biphasic scaffold from exclusively marine collagens supporting both osteogenic and chondrogenic differentiation and to find a suitable setup for in vitro chondrogenic and osteogenic differentiation of human mesenchymal stroma cells (hMSC). METHODS: Biphasic scaffolds from biomimetically mineralized salmon collagen and fibrillized jellyfish collagen were fabricated by joint freeze-drying and crosslinking. Different experiments were performed to analyze the influence of cell density and TGF-ß on osteogenic differentiation of the cells in the scaffolds. Gene expression analysis and analysis of cartilage extracellular matrix components were performed and activity of alkaline phosphatase was determined. Furthermore, histological sections of differentiated cells in the biphasic scaffolds were analyzed. RESULTS: Stable biphasic scaffolds from two different marine collagens were prepared. An in vitro setup for osteochondral differentiation was developed involving (1) different seeding densities in the phases; (2) additional application of alginate hydrogel in the chondral part; (3) pre-differentiation and sequential seeding of the scaffolds and (4) osteochondral medium. Spatially separated osteogenic and chondrogenic differentiation of hMSC was achieved in this setup, while osteochondral medium in combination with the biphasic scaffolds alone was not sufficient to reach this ambition. CONCLUSIONS: Biphasic, but monolithic scaffolds from exclusively marine collagens are suitable for the development of osteochondral constructs.

An Anti-Inflammatory PPAR-γ Agonist from the Jellyfish-Derived Fungus Penicillium chrysogenum J08NF-4.

An investigation of the jellyfish-derived fungus Penicillium chrysogenum J08NF-4 led to the isolation of two new meroterpene derivatives, chrysogenester (1) and 5-farnesyl-2-methyl-1-O-methylhydroquinone (2), and four known farnesyl meroterpenes. Docking analysis of 1 showed that it binds to PPAR-γ in the same manner as the natural PPAR-γ agonist amorfrutin B (7). Compound 1 activated PPAR-γ in murine Ac2F liver cells and increased nuclear PPAR-γ protein levels in murine RAW 264.7 macrophages. Because one of the main biological functions of PPAR-γ agonists is to suppress inflammatory response, an in vitro study was performed to explore the anti-inflammatory potency of 1 and the mechanism involved. In RAW 264.7 macrophages, 1 inhibited phosphorylation of the NF-κB p65 subunit and suppressed the expression of the pro-inflammatory mediators iNOS, NO, COX-2, TNF-α, IL-1ß, and IL-6. We propose 1 suppresses inflammatory responses by activating PPAR-γ and subsequently downregulating the NF-κB signaling pathway, thus reducing the expressions of pro-inflammatory mediators.

Eating jellyfish: safety, chemical and sensory properties.

BACKGROUND: People's preference for fish with a high trophic level, like Atlantic cod and tuna, leads to a large food footprint. Responsible seafood consumption should include underutilised local products; hence the culinary use of edible jellyfish can be an effective contribution. The present work focused on Catostylus tagi to contribute to the consumption of edible jellyfish in the West. RESULTS: A questionnaire conducted with 192 young people showed an interest in tasting jellyfish-based food (64.6%). The resulting product, obtained by an alternative cooking process to traditional Asian ones, was chemically characterised and underwent microbiological and heavy metals control. The results indicated its non-toxicity. Patients who were allergic to seafood as well as non-allergic volunteers revealed no allergic reaction to the jellyfish umbrella product (intakes up to 5 mg/kg body weight and 8 mg/kg, respectively). Seafood-trained panellists defined the product's main impact on the mouth as freshness (72 mg/kg body weight). The preliminary snack, a pâté, was positively accepted by allergic (7 in 9; n = 20) and non-allergic volunteers (6 in 7; n = 21). CONCLUSION: The present study confirmed that jellyfish intake is safe, even for allergic individuals, and its organoleptic properties were accepted by the study population. © 2018 Society of Chemical Industry.