Neutralizing properties of plant extracts against jellyfish venom

Cnidarian venoms are thought to have therapeutic potential
so that the research about these compounds is a field of
concern for applicative purposes. Nevertheless, at present the
fine composition, the activity and the characterization of
venom constituents are greatly unexplored. Cnidarian venoms
are complex mixtures of thousands of components, mainly
peptides, having specific bond targets. This study aims to
evaluate the neutralizing properties of natural products from
plants against cnidarian envenomation and induced pain, to
develop protective products having topical utilization. The isolation
of heterotrichous microbasic eurytele nematocysts from
tentacles of Pelagia noctiluca collected in Eastern Tyrrhenian
Sicily waters around Messina and venom extraction have
been carried out according to published methods.
Commercial extracts from Ananas comosus and Carica
papaya were formerly evaluated on cultured mouse lung
fibroblasts L979 to measure their cytotoxicity by MTT assay
and here used to prove protection against cytotoxicity of eurytele
nematocysts venom. Eurytele nematocysts induced cytotoxicity
with an IC50 of about 40×104 N/mL. The extracts
from Ananas comosus and Carica papaya resulted non-toxic,
both with an IC50>2000 g/mL. Ananas comosus extract
caused reduction of venom effects at 10 and 100 g/ml, doubling
the amount of surviving cells at the endpoint, while
Carica papaya extract was more effective at 100 g/mL than
at 10 g/mL. These preliminary results show that the studied
plant extracts can have an interest in fighting the effects of jellyfish
stings and could be good candidates for the preparation
of topical products. Further studies in progress in our laboratory
will hopefully confirm these first heartening data.