title: Zeranol induces COX-2 expression through TRPC-3 activation in the placental cells JEG-3.
abstract: Transient Receptor Potential Channels (TRPs) are commonly expressed in the reproductive tissues in human. Many female reproductive processes have been associated with these TRPs. The mycotoxin zeranol or α-zearalanol is derived from fungi in the Fusarium family. Limited exposure to zeranol appears to be safe. In North America, farmers are using synthetic zeranol to promote growth in livestock. As the health risks of exposure to residual zeranol have not been determined, this practice is disallowed in the European Community. In the present study the cellular calcium levels were elevated in JEG-3 cells treated with zeranol at or above 10nM. Subsequent study indicated that expressions of TRP channels were induced. In response to the calcium flow, ERK, P38 and PKCβ were activated and COX-2 expression was increased. Specific TRP inhibitors were employed to establish the connection between the ion channel activity and COX-2 expression, and TRPC-3 appeared to be the triggering mechanism. Since the involvement of COX-2 is implicated in placental development and parturition, exposure to this mycotoxin poses a potential threat to pregnant women.
authors.affiliation: Food and Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong.
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong.
authors.forename: Xiaoqiang
authors.initials: X
authors.lastname: Yao
authors.affiliation: Food and Nutritional Sciences Programme, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong; Biochemistry Programme, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong. Electronic address: laikleung@cuhk.edu.hk.
authors.forename: Lai K
authors.initials: LK
authors.lastname: Leung
mesh_terms: D002118:Calcium / Q000378:metabolism; D045744:Cell Line, Tumor; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism*; D004968:Estrogens, Non-Steroidal / Q000494:pharmacology*; D005260:Female; D006801:Humans; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009183:Mycotoxins / Q000494:pharmacology*; D010920:Placenta / Q000166:cytology*; D011247:Pregnancy; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D050052:TRPC Cation Channels / Q000378:metabolism*; D015029:Zeranol / Q000494:pharmacology*
chemical_list: D004968:Estrogens, Non-Steroidal; D009183:Mycotoxins; D019253:Proto-Oncogene Proteins c-bcl-2; D050052:TRPC Cation Channels; C104603:TRPC3 cation channel; D015029:Zeranol; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D020928:Mitogen-Activated Protein Kinases; D002118:Calcium
keywords: COX-2; Placental cells; TRP; Zeranol