Apoptosis-like cell death induced by nematocyst venom from Chrysaora helvola Brandt jellyfish and an in vitro evaluation of commonly used antidotes

作者：Qu, Xiaosheng^*; Xia, Xianghua; Lai, Zefeng; Zhong, Taozheng; Li, Gang; Fan, Lanlan; Shu, Wei^*

来源：Comparative Biochemistry and Physiology C-Toxicology & Pharmacology, 2016, 180: 31-39.

DOI：10.1016/j.cbpc.2015.10.012

• Chrysaora helvola
• Nematocyst venom
• Cytotoxicity
• Apoptosis
• Antidote
• PIA(2)
• Ca2+ channel blockers

The present work investigated the in vitro cytotoxicity of nematocyst venom (NV) from Chrysaora helvola Brandt (C. helvola) jellyfish against human MCF-7 and CNE-2 tumor cell lines. Potent cytotoxicity was quantified using the MTT assay (LC50 = 12.07 +/- 3.13 and 1.6 +/- 0.22 mu g/mL (n = 4), respectively). Apoptosis-like cell death was further confirmed using the LDH release assay and Annexin V/PI double staining-based flow cytometry analysis. However, only activation of caspase-4 was observed. It is possible that some caspase-independent pathways were activated by the NV treatment. Since no reference or antivenom is available, the effects of several commonly used antidotes on the cytotoxicity of NV were examined on more sensitive CNE-2 cells to determine the appropriate emergency measures for envenomation by C helvola. The phospholipase A(2) (PLA(2)) inhibitor para-bromophenacyl bromide (pBPB) showed no protective effect, while Mg2+ potentiated cytotoxicity. Voltage gated L-type Ca2+ channel blockers (verapamil, nifedipine and felodipine) and Na-Ca2+ exchanger inhibitor KB-R7943 also showed no effect. Assays using Ca2+-free culture media or the intracellular Ca2+ chelator BAPTA also could not inhibit the cytotoxicity. Taken together, these results suggest that PIA(2) and Ca2+ are not directly involved in the cytotoxicity of NV from C. helvola. Our work also suggests caution regarding the choice for first aid for envenomation by C. helvola jellyfish.

• 出版日期2016-2
• 单位广西中医药大学; 广西医科大学