Public Library of Science

Abstract

Worldwide there are more than 10,000 reported jellyfish stings annually that can potentially cause local dermatonecrosis and systemic symptoms including cardiovascular instability, respiratory distress, and anaphylaxis. When dermal tissue is exposed to jellyfish venom, there is a significant inflammatory reaction and upregulation of matrix metalloproteinase (MMP) activity. Other than its use as an antibiotic, tetracycline is also an effective metalloproteinase inhibitor but has never been studied as a topical treatment for jellyfish stings. This study investigated the role of MMP activity in dermal toxicity after a sting from the Nemopilema nomurai Scyphozoan jellyfish and the ability of tetracycline to inhibit the clinical sequelae after envenomation. After treating human keratinocyte and mouse fibroblast models with isolated N nomurai jellyfish venom and different concentrations of tetracycline, the investigators measured MMP activity with gelatin zymography, electrophoresis, and Western blot analysis. Additionally, the investigators performed in vivo experiments using envenomated rabbit models treated with lanolin cream alone or containing tetracycline. Finally, the authors analyzed the histological effects of envenomated rabbit skin after treatment with tetracycline. After venom exposure, MMP activity significantly increased but was suppressed in the presence of tetracycline. In the in vivo rabbit models, the maximal skin lesion size was noted after 24 hours and steadily decreased over a period of 48 hours. Topical application of lanolin cream with tetracycline to envenomated areas of skin significantly reduced maximal lesion size at 24 hours. Additionally, histological analysis showed a decreased level of hemorrhage and neutrophilic infiltration for skin treated with tetracycline. This study suggested that tetracycline is able to downregulate MMP activity induced by N nomurai jellyfish venom and can also decrease maximal lesion size when applied topically. The authors conclude that tetracycline creams may be beneficial as a first-aid dermal treatment after jellyfish envenomation. Limitations of the study include applicability to human skin and accessibility to tetracycline cream shortly after jellyfish envenomation. (PLoS One. 2013;8:e57658) C Kang, YB Jin, J Kwak, et al.