title: Cyanea capillata tentacle-only extract as a potential alternative of nematocyst venom: its cardiovascular toxicity and tolerance to isolation and purification procedures.
abstract: As the proteins with cardiovascular toxicity in jellyfish nematocyst venom and tentacle-only extract (TOE) are probably encoded by the same gene, TOE provides a potential alternative of nematocyst venom with much richer source for acquisition of such proteins. In this study, Cyanea capillata nematocyst venom and TOE (5mg/kg) both exhibited cardiovascular toxicity in rats, and TOE caused blood pressure reduction in slightly greater amplitude than nematocyst venom 3min after intravenous administration. SDS-PAGE suggested high likeliness that they both contained the same bioactive protein. The activity of TOE was dose-dependent within 1.25-5mg/kg, but not at higher concentrations. The cardiovascular activity of TOE sustained a major loss after exposure to 60 degrees C, and was totally abolished after exposure to 80 degrees C. Within the pH range of 7-11, the activity of TOE was well preserved, and rapidly attenuated in pH below 5. At 4 degrees C, TOE lost cardiovascular toxicity after preservation for 7 days, which occurred only after an 8-h preservation at 20 degrees C. Repeated freeze-thawing and freeze-drying did not significantly affect the toxicity of TOE. Buffer solutions obviously affected the toxicity of TOE, and 0.02mol/L HAc (pH 6.0) was optimal. These results provide experimental data for optimizing the conditions for isolating the proteins with cardiovascular toxicity from jellyfish TOE, which serves as a promising alternative source of nematocyst venom.
authors.affiliation: Department of Chemical Defense Medicine, Faculty of Naval Medicine, Second Military Medical University, No. 800, Xiangyin Road, Shanghai 200433, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Xiao
authors.forename: Qian
authors.initials: Q
authors.lastname: He
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Guo
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Fei
authors.initials: F
authors.lastname: Nie
authors.forename: Yue
authors.initials: Y
authors.lastname: Li
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Ye
authors.forename: Liming
authors.initials: L
authors.lastname: Zhang
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D003064:Cnidarian Venoms / Q000737:chemistry* / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004356:Drug Storage; D005612:Freeze Drying; D005615:Freezing; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D037401:Scyphozoa / Q000166:cytology* / Q000502:physiology*
chemical_list: D003064:Cnidarian Venoms