Cnidom analysis combined with an in vitro evaluation of the lytic, cyto- and neurotoxic potential of <i>Cyanea capillata</i> (Cnidaria: Scyphozoa)

Abstract

SUMMARY:The cnidocysts and the lytic, cyto-and neurotoxic potency of a large specimen of Cyanea capillata (L.) with 55 cm umbrella diameter were compared with those of a pooled C. capillata sample (average ø 14 cm) in order to investigate organismal developments at a cellular and biochemical level. Nematocysts of the type A-isorhiza in both fishing tentacles and oral arms and the O-isorhizas of oral arms were enlarged in the 55 cm specimen. Additionally, the number of nematocysts per battery in the fishing tentacles was increased. Increased gill cell toxicity and neurotoxic activity were demonstrated for the fishing tentacle venom of the 55 cm C. capillata in comparison with the smaller medusae. A two-fold higher haemolytic activity was detected for the venom of oral arms obtained from the large C. capillata compared with the oral arm venom prepared from the smaller medusae.Keywords: Cnidaria, Scyphozoa, Cyanea, jellyfish, cnidom, venom, cytotoxicity, neurotoxicity. RESUMEN: Análisis del cnidoma combinado con una evaluación in vitro del potencial lítico, cyto-y neurotóxicos de Cyanea Capillata (Cnidaria: Scyphozoa). -Con el fin de estudiar la evolución ontogenética a un nivel celular y bioquímico de los cnidocistos de la potencia lítica, y las características cito-y neurotóxicas de Cyanea capillata (L.), se ha comparado un ejemplar de 55 cm de diámetro de umbrela de la especie con una muestra de varios ejemplares de C. capillata (promedio 14 cm de diámetro). Tanto los nematocistos del tipo A isorhiza de los tentáculos marginales como en los mesentéricos y los nematocistos del tipo O isorhizas de tentáculos orales fueron mayores en el ejemplar de C. capillata de 55 cm. Además, el número de nematocistos por zona de agregación fue mayor en el ejemplar de 55 cm. En cuanto a la actividad tóxica de los cnidocistos, ésta fue superior tanto a nivel de célula como de la actividad de la toxina (veneno) en los tentáculos marginales del ejemplar de 55 cm frente a los ejemplares más pequeños de la especie. También se observó una actividad hemolítica de la toxina (veneno) dos veces superior en los cnidocistos de los tentáculos marginales del ejemplar grande, 55 cm de C. capillata frente a los ejemplares pequeños.

Evaluation of Cyanea capillata Sting Management Protocols Using Ex Vivo and In Vitro Envenomation Models

“…However, precise quantification of nematocyst discharge in response to test solutions proved difficult given the complexity of the Cyanea cnidome, which consists of euryteles, birhopaloids and three different isorhizas—a-isorhizas, A-isorhizas, and O-isorhizas—each with multiple size classes [ 37 ] ( Figure 1 ). It is essential to distinguish these types when evaluating discharge because studies have demonstrated that different nematocysts can vary not only in their morphology and penetrant abilities but also in their toxic effects [ 38 , 39 , 40 ]. However, precise quantification of percent discharge for each nematocyst type and size class was not possible with the microscope and camera available for this study; best efforts were made to identify cnidae types based on [ 37 ].…”

“…In our study, we noted that vinegar does not equally induce discharge in all nematocyst types, and did not elicit as much discharge as other solutions (urine, isopropanol). It is not known how each nematocyst type contributes to toxicity, but previous studies have suggested that the largest A-isorhizas and O-isorhizas disproportionately contribute to hemolysis [ 40 ], and these cnidae types were not triggered by vinegar application. Thus, it may be that vinegar does not induce discharge of the most toxic types of nematocysts, and that any discharge that occurs during the rinsing process does not contribute measurably to hemolytic activity, the functional metric of our venom activity assays.…”

Acute lion's mane jellyfish, Cyanea capillata (Cnideria: Scyphozoa), exposure to Atlantic salmon (Salmo salar L.)

“…Epithelial cytotoxicity has been reported for C. capillata and A. aurita using RTgill‐W1 cell lines (Helmholz et al., ). The fishing tentacles contain predominantly A‐isorhiza and O‐isorhiza nematocysts, whereas the oral arms dominate in O‐isorhizas (Helmholz et al., ). However, the number, size and potency of the venom contained in these different types of nematocysts vary with jellyfish size and geographical location (Helmholz et al., ; Wiebring et al., ).…”

“…As the jellyfish become trapped on the outside of the net cage, they break apart and pieces pass through into the cage. The tentacles, be they the fishing tentacles, mesenteric tentacles, oral arms or exumbrella all contain A‐, O‐ and a‐isorhizas and eurytales nematocysts although the number and characteristics of each type can vary by size and geographic location (Helmholz et al., ; Wiebring, Helmholz, Lassen, Prange, & Jarms, ). The gill cell toxicity of the venom from C. capillata and A. aurita has been examined in vitro using RTgill‐W1 cells (Helmholz, Johnston, Ruhnau, & Prange, ); however, these assays do not demonstrate the pathological effects on envenomated fish.…”

Cytotoxic and Cytolytic Cnidarian Venoms. A Review on Health Implications and Possible Therapeutic Applications

“…Furthermore, the erythrocyte lysis (HE 50 ) induced by crude venom from mesenteric tentacles of large jellyfish was greater (98 μg/mL) than that induced from small medusae extracts (177 μg/mL). Therefore, the size of fishing tentacles and of oral arms, and nematocyst (A-isorhizas and O-isorhizas) number and size that correspond to the size of umbrella, were correlated with the cytolytic potency in differently-sized Cyanea capillata (L.) showing that the greater the specimen, the higher the produced hemolysis [ 47 ]. A concentration-dependent increase of hemolysis induced by extracts from Cyanea capillata tentacles was observed also in rat erythrocytes in the presence of Ca 2+ ; this increase was attenuated by Ca 2+ channel blockers such as Diltiazem, Verapamil and Nifedipine [ 48 ].…”