title: Apoptosis induction is involved in UVA-induced autolysis in sea cucumber Stichopus japonicus.
abstract: Autolysis easily happens to sea cucumber (Stichopus japonicus, S. japonicus) for external stimulus like UV exposure causing heavy economic losses. Therefore, it is meaningful to reveal the mechanism of S. japonicas autolysis. In the present study, to examine the involvement of apoptosis induction in UVA-induced autolysis of S. japonicas, we investigated the biochemical events including the DNA fragmentation, caspase-3 activation, mitogen-activated protein kinases (MAPKs) phosphorylation and free radical formation. Substantial morphological changes such as intestine vomiting and dermatolysis were observed in S. japonicus during the incubation after 1-h UVA irradiation (10W/m(2)). The degradation of the structural proteins and enhancement of cathepsin L activity were also detected, suggesting the profound impact of proteolysis caused by the UVA irradiation even for 1h. Furthermore, the DNA fragmentation and specific activity of caspase-3 was increased up to 12h after UVA irradiation. The levels of phosphorylated p38 mitogen activated protein kinase (MAPK) and phosphorylated c-Jun.-N-terminal kinase (JNK) were significantly increased by the UVA irradiation for 1h. An electron spin resonance (ESR) analysis revealed that UVA enhanced the free radical formation in S. japonicas, even through we could not identify the attributed species. These results suggest that UVA-induced autolysis in S. japonicas at least partially involves the oxidative stress-sensitive apoptosis induction pathway. These data present a novel insight into the mechanisms of sea cucumber autolysis induced by external stress.
authors.affiliation: School of Food Science and Technology, Dalian Polytechnic University, National Engineering Research Center of Seafood, Dalian 116034, China. Electronic address: qihang@dlpu.edu.cn.
authors.forename: Hang
authors.initials: H
authors.lastname: Qi
authors.affiliation: School of Food Science and Technology, Dalian Polytechnic University, National Engineering Research Center of Seafood, Dalian 116034, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Fu
authors.affiliation: School of Food Science and Technology, Dalian Polytechnic University, National Engineering Research Center of Seafood, Dalian 116034, China.
authors.forename: Xiufang
authors.initials: X
authors.lastname: Dong
authors.affiliation: School of Food Science and Technology, Dalian Polytechnic University, National Engineering Research Center of Seafood, Dalian 116034, China.
authors.forename: Dingding
authors.initials: D
authors.lastname: Feng
authors.affiliation: School of Food Science and Technology, Dalian Polytechnic University, National Engineering Research Center of Seafood, Dalian 116034, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Li
authors.affiliation: School of Food Science and Technology, Dalian Polytechnic University, National Engineering Research Center of Seafood, Dalian 116034, China.
authors.forename: Chengrong
authors.initials: C
authors.lastname: Wen
authors.affiliation: Graduate School of Environmental and Life Science, Okayama University, Okayama 700-8530, Japan.
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Nakamura
authors.affiliation: School of Food Science and Technology, Dalian Polytechnic University, National Engineering Research Center of Seafood, Dalian 116034, China. Electronic address: zhubeiwei@163.com.
authors.forename: Beiwei
authors.initials: B
authors.lastname: Zhu
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000528:radiation effects*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010766:Phosphorylation; D012616:Sea Cucumbers / Q000166:cytology / Q000528:radiation effects*; D014466:Ultraviolet Rays
chemical_list: D020928:Mitogen-Activated Protein Kinases
keywords: Apoptosis; Autolysis; Free radical; MAPK phosphorylation; Sea cucumber Stichopus japonicus; UVA