The Cardiovascular and Neurotoxic Effects of the Venoms of Six Bony and Cartilaginous Fish Species.

Fish venoms are often poorly studied, in part due to the difficulty in obtaining, extracting, and storing them. In this study, we characterize the cardiovascular and neurotoxic effects of the venoms from the following six species of fish: the cartilaginous stingrays Neotrygon kuhlii and Himantura toshi, and the bony fish Platycephalus fucus, Girella tricuspidata, Mugil cephalus, and Dentex tumifrons. All venoms (10-100 µg/kg, i.v.), except G. tricuspidata and P. fuscus, induced a biphasic response on mean arterial pressure (MAP) in the anesthetised rat. P. fucus venom exhibited a hypotensive response, while venom from G. tricuspidata displayed a single depressor response. All venoms induced cardiovascular collapse at 200 µg/kg, i.v. The in vitro neurotoxic effects of venom were examined using the chick biventer cervicis nerve-muscle (CBCNM) preparation. N. kuhlii, H. toshi, and P. fucus venoms caused concentration-dependent inhibition of indirect twitches in the CBCNM preparation. These three venoms also inhibited responses to exogenous acetylcholine (ACh) and carbachol (CCh), but not potassium chloride (KCl), indicating a post-synaptic mode of action. Venom from G. tricuspidata, M. cephalus, and D. tumifrons had no significant effect on indirect twitches or agonist responses in the CBCNM. Our results demonstrate that envenoming by these species of fish may result in moderate cardiovascular and/or neurotoxic effects. Future studies aimed at identifying the molecules responsible for these effects could uncover potentially novel lead compounds for future pharmaceuticals, in addition to generating new knowledge about the evolutionary relationships between venomous animals.

Marine Scorpaenidae Envenomation in Travelers: Epidemiology, Management, and Prevention.

BACKGROUND: The Scorpaenidae are a large family of venomous marine fish that include scorpionfish, lionfish, and stonefish. Although most stonefish are confined to the Indo-Pacific, scorpionfish are distributed in the tropics worldwide, and two species of Indo-Pacific lionfish were inadvertently introduced into the Eastern Atlantic in the 1990s. Since then, lionfish have invaded shallow reef systems in the Eastern Atlantic, Gulf of Mexico, and Caribbean Sea. All of these regions are popular travel destinations for beachcombing, fishing, swimming, and scuba diving-recreational activities that increase risks of Scorpaenidae envenomation. METHODS: To meet the objectives of describing species-specific presenting clinical manifestations, diagnostic and treatment strategies, and outcomes of Scorpaenidae envenomation in travelers, Internet search engines were queried with the key words. RESULTS: Well-conducted, retrospective epidemiological investigations of Scorpaenidae envenomation case series concluded: (1) most cases occurred in young adult male vacationers visiting endemic regions; (2) victims sought medical attention for pain control within 2 hours of injury and presented with intense pain, edema, and erythema in affected extremities; (3) systemic manifestations and surgical interventions were relatively uncommon following initial management with hot water soaks and parenteral analgesics; (4) all cases required tetanus prophylaxis; deeply penetrating, lacerated, and necrotic wounds required antibiotic prophylaxis; and (5) equine Fab stonefish antivenom does have antigen-neutralizing cross-reactivities with both Indo-Pacific and Atlantic Scorpaenidae species and is indicated in severe scorpionfish and stonefish envenomation worldwide. CONCLUSIONS: Travel medicine practitioners should counsel their patients about Scorpaenidae envenomation risks in endemic regions and maintain a high index of suspicion regarding Scorpaenidae envenomation in all travelers returning from tropical beach and ocean holidays and reporting painful fish sting injuries.

The complete mitochondrial genome of the Hwanghae Rockfish Sebastes koreanus (Scorpaenidae, Scorpaeniformes).

The complete mitochondrial genome sequence of Sebastes koreanus was determined by next-generation sequencing. The total genome was 16,499 bp in length, comprising two rRNA, 22 tRNA and 13 protein-coding genes (PCGs), as well as the mtDNA control region. The genome constitutes 27.9% A, 26.6% T, 17.1% G and 28.4% C, showing a slight AT bias (54.5%). Of the 13 mitochondrial PCGs, 12 have an ATG start codon while COX1 had a GTG start codon; the incomplete stop codon (T) was present in the ND3, ND4 and Cytb genes. The anti-G bias was considerably lower at the third codon position of PCGs (8.8%). The complete mitogenome sequence of S. koreanus will contribute to molecular phylogenetic and evolutionary analyses of Sebastinae and to the identification of its genetic populations in the Yellow Sea.

Thalassophryne nattereri fish venom: from the envenoming to the understanding of the immune system

Thalassophryne nattereri (niquim) is a venomous fish found off North and Northeast coast of Brazil, where it is known by the severity of the accidents involving humans. This review article is divided into four topics. The first one provides a brief description of the animal biology and its distribution off Brazilian coastal waters, the venom apparatus, signs and symptoms observed in envenomated humans and also describes envenomation in mice. The second topic describes the use of modern genetic approach and mass spectrometry for identification of highly expressed genes in its venom glands and the sequence of major toxins. The third chapter offers a detailed study of tissue injury induced by the venom and reveals the role of toxins that impair inflammation reduction. Finally, the fourth section expands the understanding of many extrinsic and intrinsic essential factors in maintaining survival of memory B cell compartment. Our results demonstrate the wide possibilities for research in the area of toxinology, also the necessity of interconnection among biochemistry, pharmacology and immunology areas for the expansion of knowledge and for generation of innovation.

Thalassophryne nattereri fish venom: from the envenoming to the understanding of the immune system

Thalassophryne nattereri (niquim) is a venomous fish found off North and Northeast coast of Brazil, where it is known by the severity of the accidents involving humans. This review article is divided into four topics. The first one provides a brief description of the animal biology and its distribution off Brazilian coastal waters, the venom apparatus, signs and symptoms observed in envenomated humans and also describes envenomation in mice. The second topic describes the use of modern genetic approach and mass spectrometry for identification of highly expressed genes in its venom glands and the sequence of major toxins. The third chapter offers a detailed study of tissue injury induced by the venom and reveals the role of toxins that impair inflammation reduction. Finally, the fourth section expands the understanding of many extrinsic and intrinsic essential factors in maintaining survival of memory B cell compartment. Our results demonstrate the wide possibilities for research in the area of toxinology, also the necessity of interconnection among biochemistry, pharmacology and immunology areas for the expansion of knowledge and for generation of innovation.

[Seafood poisonings. Part II. Fish poisonings]. / Zatrucia zywnoscia pochodzenia morskiego. Czesc II. Zatrucia rybami.

Fish plays a significant role in human life, mainly as part of a balanced healthy diet and a good source of many of nutrients. However, contact with fish may be harmful or even life-threatening to man. Toxic effects, that fish exerts toward men (ichthyotoxism), result from envenomations by poison. ous fish equipped in venom apparatus (ichthyoacanthotoxism), direct contact with venom produced by skin glandules (ichthyocrinotoxism), or consuming fish containing toxins for nutritional purposes (ichthyosarcotoxism). In the present review, different fish-borne food poisonings are presented including their etiology, pathogenesis, symptomatology and treatment. In fact, the majority of fish poisonings are intoxications with toxins primary produced by bacteria, cyanobacteria and algae. These are consumed and accumulated in the food chain by herbivorous and predatory fish, that in turn may be a cause of poisonings in humans.

Efectos tóxicos y manejo de las lesiones provocadas por el pez león (Pteroisvolitans, P. miles) / Toxic effects and management and injuries caused by the lion fish(Pteroisvolitan, P. miles)

El Pez León (Pterois volitans y Pteroismiles), especie registrada como invasora en el Atlántico occidental; se ha constituido en un poderoso depredador gracias a que no tiene un antagonista natural en la segunda barrera coralina más grande del mundo, poniendo en riesgo a las especies marinas endémicas de la zona, así com o a nadadores, buzos recreativos, comerciales y pescadores que entran en contacto con el pez. El pinchazo del pez león es venenoso, tiene aproximadamente 17 espinas dorsales,pélvicas y anal, cada uno contiene un tubo que se conecta al extremo de una glándula venenosa que segrega 3 a 10mg de veneno por espina. El mecanismo de intoxicación se produce cuando la persona pisa o toca al pez, ejerciendo presión sobre las espinas y al penetrar la piel las glándulas venenosas liberan el veneno. La toxina inoculada puede causar dolor intenso, fiebre, parálisis respiratoria humana e insuficiencia circulatoria. La toxicidad del veneno es debida a antigénicos de proteínas de alto peso molecular. El tratamiento se basa en la termolabilidad de dichas proteínas, bloquear la respuesta inflamatoria sistémica y las posibles complicaciones. Con esta revisión bibliográfica se pretende ampliar sobre los efectos tóxicos y el manejo de las lesiones provocadas por el pez león, a fin de informar a la comunidad médica hondureña de los problemas de salud causada...

[Medical treatment during fish envenomation]. / Postepowanie w zatruciu jadami ryb.

Expositions to fish venoms should be treated as a separate group of intoxications because of their different diagnostic procedure. Until now, there are over 220 venomous fish species described, but skin excretions are potentially toxic for humans. Cases of fish envenomations (37), consulted by Poison Information Centres in Poland, as well as described in literature and contained in Micromedex database were analyzed. The course of envenomation, medical management during exposition to venomous of Chondrichthyes and Osteichthyes, freshwater and marine fishes were resolved. Injuries caused by venoms fishes were similarly treated, usually symptomatic. Specific antivenoms are available only for two fish species. Each patient exposed to sting or bite should be examined and observed. If characteristic sings and symptoms of envenomation are present, proper medical management should be proceed.

Natterins, a new class of proteins with kininogenase activity characterized from Thalassophryne nattereri fish venom

A novel family of proteins with kininogenase activity and unique primary structure was characterized using combined pharmacological, proteomic and transcriptomic approaches of Thalassophryne nattereri fish venom. The major venom components were isolated and submitted to bioassays corresponding to its main effects: nociception and edema. These activities were mostly located in one fraction (MS3), which was further fractionated. The isolated protein, named natterin, was able to induce edema, nociception and cleave human kininogen and kininogen-derived synthetic peptides, releasing kallidin (Lys-bradykinin). The enzymatic digestion was inhibited by kallikrein inhibitors as Trasylol and TKI. Natterin N-terminal peptide showed no similarity with already known proteins present in databanks. Primary structure of natterin was obtained by a transcriptomic approach using a representative cDNA library constructed from T. nattereri venom glands. Several expressed sequence tags (ESTs) were obtained and processed by bioinformatics revealing a major group (18%) of related sequences unknown to gene or protein sequence databases. This group included sequences showing the N-terminus of isolated natterin and was named Natterin family. Analysis of this family allowed us to identify five related sequences, which we called natterin 1-4 and P. Natterin 1 and 2 sequences include the N-terminus of the isolated natterin. Furthermore, internal peptides of natterin 1-3 were found in major spots of whole venom submitted to mass spectrometry/2DGE. Similarly to the ESTs, the complete sequences of natterins did not show any significant similarity with already described tissue kallikreins, kininogenases or any proteinase, all being entirely new. These data present a new task for the knowledge of the action of kininogenases and may help in understanding the mechanisms of T. nattereri fish envenoming, which is an important medical problem in North and Northeast of Brazil.

[Evaluation of Antilles fish ciguatoxicity by mouse and chick bioassays]. / Evaluation de la ciguatoxicité de poissons des antilles par les bioessais souris et poussin.

Ciguatera is a common seafood poisoning in Western Atlantic and French West Indies. Ciguatera fish poisoning in the Caribbean is a public health problem. A toxicological study was carried out on 178 Caribbean fish specimens (26 species) captured off Guadeloupe and Saint Barthelemy between 1993 and 1999. The mouse bioassay and the chick feeding test were used to control fish edibility. Ciguatoxins presence was assumed when symptomatology was typical of ciguatera in mouse and chick. Fishes were classified in three groups: non toxic fish (edible), low toxic fish (not edible) and toxic fish (not edible). 75% of fishes were non toxic. Toxic fish specimens belonged to four families of high trophic level carnivores: Carangidae, Lutjanidae, Serranidae et Sphyraenidae. Percentages of toxic fishes to humans reached 55% for Caranx latus and 33% for Caranx bartholomaei and Caranx lugubris. Only a significant correlation between weight and toxicity was only found for C. latus and snappers. Small carnivorous groupers (Serranidae) were also toxic. Atoxic fish species were (a) pelagic fish (Coryphaena hippurus, Auxis thazard and Euthynnus pelamis), (b) invertebrates feeders (Malacanthus plumieri, Balistes vetula), (c) small high-risk fish or (d) fish of edible benthic fish families. Liver of four fishes (Mycteroperca venenosa, Caranx bartholomaei, Seriola rivoliana, Gymnothorax funebris) contained ciguatoxins at a significant level although their flesh was safe. This study confirms the usefulness of mouse and chick bioassays for sanitary control of fish.

[Poisonous fish: first aid in cases of poisoning]. / Peces ponzoñosos. Cómo actuar ante una lesión.

The author reveals aspects regarding the main fish species, vertebrate marine animals, having a habitat in our coastal area or which frequently visit our coasts which can produce some sort of poisonous lesion in humans whenever humans come into contact with these fish in their natural environment either accidentally or be being handled, especially while fishing. The author describes and identifies the species most frequently found in Spanish waters, pointing out their characteristics as well as the lesions they can produce, highlighting their symptoms and the corresponding recommended treatment in situ and in health centers.

The toxicology of Trachinus vipera? The lesser weeverfish

The biology and toxicology of the lesser weeverfish, Trachinus vipera, is presented in a homeopathic repertory fashion to supplement the existing materia medica. (AU)

Tetraodon fluviatilis, a new puffer fish model for genome studies.

The puffer fish Fugu rubripes rubripes was recently introduced by S. Brenner et al. (1993, Nature 366: 265-268) as a new model for genomic studies. Due to difficulties in obtaining material from this Japanese marine puffer, we have started work on Tetraodon fluviatilis, a small, freshwater puffer fish that can be kept and bred in an aquarium. It was originally described by E. Hinegardner (1968, Am. Nat. 102(928) 517-523) as the teleost with the smallest amount of DNA per cell (0.4 pg, 380 Mb). To estimate the extent of divergence between T. fluviatilis and F. r. rubripes, part of the mitochondrial cytochrome b (cyt b) gene from both fishes was cloned and sequenced. A comparison of these two sequences indicated that F.r. rubripes and T. fluviatilis diverged approximately 18-30 million years ago, and phylogenetic analysis placed both fishes at the base of the Perciformes lineage. To facilitate and extend further the use of the puffer fish as a model for genome studies, we have constructed and characterized a T. fluviatilis cDNA library.

Genomic structure and sequence of the pufferfish (Fugu rubripes) growth hormone-encoding gene: a comparative analysis of teleost growth hormone genes.

A nested polymerase chain reaction (PCR) technique for amplifying a fragment of the gene (GH) encoding teleost growth hormone has been developed. Using this technique, a fragment of the pufferfish, Fugu rubripes and Arothron maculatus, dwarf gourami, Colisa lalia; guppy, Poecilia reticulata; and goldfish, Carassius auratus GH genes were cloned. The Fugu rubripes (Fugu) gene fragment was used to isolate the GH gene from a Fugu genomic library. The complete nucleotide sequence of a 8.5-kb SacI genomic fragment containing the Fugu GH gene has been determined. The GH gene spans 2.5 kb from the first codon to polyadenylation signal, and contains six exons and five introns similar to the GH genes of salmonids, tilapia, barramundi, flounder and yellowtail. The GH introns contain microsatellite and satellite sequences. The microsatellites found in the fifth intron of the GH gene are also present in the corresponding introns of tilapia, barramundi and flounder GH genes. Southern analysis revealed that the GH gene is a single-copy gene in the Fugu. The promoter region of the Fugu GH gene contains conserved sequences that are likely to be involved in the pituitary-specific expression of the gene. A phylogenetic tree of nucleotide (nt) sequences of all known teleost GH genes has been inferred using the distance matrix method. The topology of this tree reflects the major phylogenetic groupings of teleosts. The intron patterns and repetitive sequences of GH genes can serve as useful natural markers for the classification and phylogenetic studies of teleosts.

[Risk factors of ciguatera in the French West Indies in Saint-Barthélémy, Saint-Martin and Anguilla]. / Facteurs de risque ciguatérique aux Antilles dans la région de Saint-Barthélémy, Saint-Martin et Anguilla.

An epidemiological study on ciguatera fish poisoning in the French West Indies (St-Barthelemy, St-Martin and Anguilla) was conducted during the years 1985-1986. The investigation on intoxications shows a non seasonal significant prevalence. Though it was difficult to list the cases, the morbidity seems to vary between 7 and 30 per thousand. A study of fish toxicity was realised; 46 different species were tested (individually or by pools) by the mosquito bio-test. Observations of intoxications give the following results: High risk species: Caranx bartholomaei, C. lugubris, Seriola dumerili, Lutjanus apodus, L. jocu, Pristipomoides macrophtalmus, Gymnothorax funebris, G. moringa, Scomberomorus cavalla, S. regalis, Mycteroperca venenosa, M. tigris, Epinephelus morio, Sphyraena barracuda. Intermediate species: Caranx latus, C. ruber, Lachnolaimus maximus, Lutjanus analis, L. buccanella, L. griseus, Malacanthus plumieri, Scomberomorus maculatus. Low risk species: Balistes vetula, Alectis ciliaris, Haemulon album, Bodianus rufus, Halichoeres radiatus, Priacanthus arenatus, Alphestes afer. Many species are involved in the toxic food chain. New ones have been identified, but it is difficult to determine the toxic level range. A cartography is presented but no place is free of risk. A research of Gambierdiscus toxicus, the causal agent, on algal surface from dead corals was conducted around St-Barthelemy and St-Martin. The dinoflagellate is found in low or medium populations all around the islands with no difference between North and South. There is a maximal activity during the spring. A model of the epidemiology of the ciguatera in the area is proposed.