title: Secreted phospholipase A2 of Clonorchis sinensis activates hepatic stellate cells through a pathway involving JNK signalling.
abstract: BACKGROUND
  Secreted phospholipase A2 (sPLA2) is a protein secreted by Clonorchis sinensis and is a component of excretory and secretory products (CsESPs). Phospholipase A2 is well known for its role in liver fibrosis and inhibition of tumour cells. The JNK signalling pathway is involved in hepatic stellate cells (HSCs) activation. Blocking JNK activity with SP600125 inhibits HSCs activation. In a previous study, the protein CssPLA2 was expressed in insoluble inclusion bodies. Therefore, it's necessary to express CssPLA2 in water-soluble form and determine whether the enzymatic activity of CssPLA2 or cell signalling pathways is involved in liver fibrosis caused by clonorchiasis.
  
  
  METHODS
  Balb/C mice were given an abdominal injection of MBP-CssPLA2. Liver sections with HE and Masson staining were observed to detect accumulation of collagen. Western blot of mouse liver was done to detect the activation of JNK signalling pathway. In vitro, HSCs were incubated with MBP-CssPLA2 to detect the activation of HSCs as well as the activation of JNK signalling pathway. The mutant of MBP-CssPLA2 without enzymatic activity was constructed and was also incubated with HSCs to check whether activation of the HSCs was related to the enzymatic activity of MBP-CssPLA2.
  
  
  RESULTS
  The recombinant protein MBP-CssPLA2 was expressed soluble and of good enzymatic activity. A mutant of CssPLA2, without enzymatic activity, was also constructed. In vivo liver sections of Balb/C mice that were given an abdominal injection of 50 μg/ml MBP-CssPLA2 showed an obvious accumulation of collagen and a clear band of P-JNK1 could be seen by western blot of the liver tissue. In vitro, MBP-CssPLA2, as well as the mutant, was incubated with HSCs and it was proved that activation of HSCs was related to activation of the JNK signalling pathway instead of the enzymatic activity of MBP-CssPLA2.
  
  
  CONCLUSIONS
  Activation of HSCs by CssPLA2 is related to the activation of the JNK signalling pathway instead of the enzymatic activity of CssPLA2. This finding could provide a promising treatment strategy to interrupt the process of liver fibrosis caused by clonorchiasis.
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China.
authors.forename: Yinjuan
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China.
authors.forename: Mei
authors.initials: M
authors.lastname: Shang
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Jian
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China.
authors.forename: Caiqin
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China.
authors.forename: Adham Sameer A
authors.initials: AS
authors.lastname: Bardeesi
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China.
authors.forename: Zhaolei
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China.
authors.forename: Tingjin
authors.initials: T
authors.lastname: Chen
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China.
authors.forename: Lu
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China.
authors.forename: Lina
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China.
authors.forename: Ai
authors.initials: A
authors.lastname: He
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China.
authors.forename: Zhiyue
authors.initials: Z
authors.lastname: Lv
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China.
authors.forename: Xinbing
authors.initials: X
authors.lastname: Yu
authors.affiliation: Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, People's Republic of China. xuerong2@mail.sysu.edu.cn.|Key Laboratory of Tropical Disease Control (Sun Yat-sen University), Chinese Ministry of Education, Guangzhou, Guangdong, 510080, People's Republic of China. xuerong2@mail.sysu.edu.cn.|Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, Guangdong, 510080, People's Republic of China. xuerong2@mail.sysu.edu.cn.
authors.forename: Xuerong
authors.initials: X
authors.lastname: Li
mesh_terms: D000818:Animals; D003001:Cloning, Molecular; D003004:Clonorchis sinensis / Q000201:enzymology*; D055166:Hepatic Stellate Cells / Q000469:parasitology / Q000502:physiology*; D020935:MAP Kinase Signaling System / Q000187:drug effects*; D051379:Mice; D008807:Mice, Inbred BALB C; D054497:Phospholipases A2, Secretory / Q000235:genetics / Q000494:pharmacology*; D011994:Recombinant Proteins / Q000494:pharmacology
chemical_list: D011994:Recombinant Proteins; D054497:Phospholipases A2, Secretory
keywords: Cholangiocarcinoma; Clonorchis sinensis; Enzyme; JNK signalling pathway; Liver fibrosis; Phospholipase A2