title: Schistosoma japonicum egg antigen up-regulates fibrogenesis and inhibits proliferation in primary hepatic stellate cells in a concentration-dependent manner.
abstract: OBJECTIVE
  To investigate the effects of different concentrations of Schistosoma japonicum (S. japonicum) egg antigen on fibrogenesis and apoptosis in primary hepatic stellate cells (HSCs).
  
  
  METHODS
  A mouse model of schistosomiasis-associated liver fibrosis (SSLF) was established by infecting mice with schistosomal cercaria via the abdomen. HSCs were isolated from SSLF mice by discontinuous density gradient centrifugation, and their identity was confirmed by immunofluorescence double staining of α-smooth muscle actin (α-SMA) and desmin. The growth inhibitory effect and 50% inhibitory concentration (IC50) of S. japonicum egg antigen for primary HSCs (24 h) were determined using a cell counting kit-8 (CCK-8) assay. The expression levels of α-SMA, matrix metalloproteinase-9 (MMOL/LP-9) and tissue inhibitor of metalloproteinases-1 (TIMP-1) in HSCs in response to different concentrations of S. japonicum egg antigen were detected by Western blotting and real-time reverse transcription-polymerase chain reaction. The levels of phospho-P38 (P-P38), phospho-Jun N-terminal kinase (P-JNK) and phospho-Akt (P-AKT) in HSCs were detected by Western blotting.
  
  
  RESULTS
  An SSLF mouse model was established, and primary HSCs were successfully isolated and cultured. S. japonicum egg antigen inhibited HSC proliferation in a concentration-dependent manner. The IC50 of the S. japonicum egg antigen was 244.53 ± 35.26 μg/mL. S. japonicum egg antigen enhanced α-SMA expression at both the mRNA and protein levels and enhanced TIMP-1 expression at the mRNA level in HSCs (P < 0.05), whereas the expression of MMOL/LP-9 was attenuated at both the mRNA and protein levels in a concentration-dependent manner (P < 0.05). A high concentration of S. japonicum egg antigen enhanced P-P38, P-JNK and P-AKT activation (P < 0.05). The changes in α-SMA and MMOL/LP-9 expression induced by S. japonicum egg antigen were closely correlated with P-P38 and P-JNK activation (P < 0.05). The attenuation of MMOL/LP-9 was also correlated with P-AKT activation (P < 0.05), but the increase in α-SMA expression was not. TIMP-1 expression was not correlated with P-P38, P-JNK or P-AKT activation.
  
  
  CONCLUSIONS
  S. japonicum egg antigen promotes fibrogenesis, activates the P38/JNK mitogen-activated protein kinase and AKT/PI3K signaling pathways and inhibits proliferation in primary HSCs isolated from SSLF mice in a concentration-dependent manner.
authors.affiliation: Institute of Liver Diseases, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei Province, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Liu
authors.forename: Mi
authors.initials: M
authors.lastname: Wang
authors.forename: Xiao-Dan
authors.initials: XD
authors.lastname: Lu
authors.forename: Shu-Juan
authors.initials: SJ
authors.lastname: Zhang
authors.forename: Wang-Xian
authors.initials: WX
authors.lastname: Tang
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D000947:Antigens, Helminth / Q000276:immunology*; D017209:Apoptosis; D015415:Biomarkers / Q000378:metabolism; D049109:Cell Proliferation; D002478:Cells, Cultured; D058487:Cercaria; D003893:Desmin / Q000378:metabolism; D004195:Disease Models, Animal; D015801:Helminth Proteins / Q000276:immunology*; D055166:Hepatic Stellate Cells / Q000276:immunology / Q000378:metabolism / Q000469:parasitology* / Q000473:pathology; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D008099:Liver / Q000276:immunology / Q000378:metabolism / Q000469:parasitology* / Q000473:pathology; D008103:Liver Cirrhosis / Q000276:immunology / Q000378:metabolism / Q000469:parasitology* / Q000473:pathology; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D010063:Ovum / Q000276:immunology*; D010766:Phosphorylation; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D012549:Schistosoma japonicum / Q000254:growth & development / Q000276:immunology / Q000472:pathogenicity*; D012554:Schistosomiasis japonica / Q000276:immunology / Q000378:metabolism / Q000469:parasitology* / Q000473:pathology; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D000199:Actins; D000947:Antigens, Helminth; D015415:Biomarkers; D003893:Desmin; D015801:Helminth Proteins; C560825:Timp1 protein, mouse; D019715:Tissue Inhibitor of Metalloproteinase-1; C544013:alpha-smooth muscle actin, mouse; D051057:Proto-Oncogene Proteins c-akt; D048031:JNK Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D020780:Matrix Metalloproteinase 9; C501830:Mmp9 protein, mouse
keywords: Akt; Hepatic stellate cells; Liver fibrosis; Mitogen-activated protein kinase; Schistosomiasis