Transforming growth factor beta1 regulates angiotensin II type I receptor gene expression in the extravillous trophoblast cell line SGHPL-4.
The angiotensin II type 1 (AT1) receptor, transforming growth factor beta1 (TGFbeta1) and Oncostatin M (OSM) control key pathways that may be important during placentation. Although interactions between them exist in other tissues, trophoblast cells have not been investigated. Extravillous trophoblast cells, SGHPL-4, were stimulated with 10 ng/ml TGFbeta1 +/- 100 ng/ml OSM for 24 h. Real-time PCR showed that AT1 expression increased 2.76-fold [95% confidence interval (CI) = 1-6.74, P = 0.05] in response to TGFbeta1 and 4.21-fold (95% CI = 1.33-11.76, P = 0.03) with TGFbeta1 + OSM. Luciferase reporter gene constructs containing three haplotypes of the 59 flanking region of the AT1 receptor gene were transfected into SGHPL-4 and HepG2 cells and stimulated with 0.1, 1 and 10 ng/ml TGFbeta1 and 50 ng/ml OSM. Responses were dose and cell dependent. Luciferase activity increased in HepG2 cells in response to TGFbeta1 alone or together with OSM (P < 0.001); transcriptional activation differed between AT1 receptor gene haplotypes. In SGHPL-4 cells, luciferase activity was reduced on exposure to low concentrations of TGFbeta1 or high concentrations of TGFbeta1 combined with OSM (P = 0.003); the response was unaffected by haplotype. Interaction between AT1 and TGFbeta1 is a novel observation in trophoblast and suggests new avenues for the study of placentation.
Tower
C L
CL
Division of Clinical Chemistry, Institute of Genetics, School of Molecular Medical Sciences, University Hospital, Nottingham, UK.
Chappell
S L
SL
Morgan
K
K
Kalsheker
N
N
Baker
P N
PN
Morgan
L J
LJ
D001483:Base Sequence; D002460:Cell Line; D045744:Cell Line, Tumor; D003001:Cloning, Molecular; D016207:Cytokines / Q000494:pharmacology; D017931:DNA Primers; D005786:Gene Expression Regulation / Q000187:drug effects; D017930:Genes, Reporter; D006801:Humans; D008156:Luciferases / Q000235:genetics; D053683:Oncostatin M; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D044140:Receptor, Angiotensin, Type 1 / Q000235:genetics*; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D014327:Trophoblasts / Q000166:cytology
D016207:Cytokines; D017931:DNA Primers; C508351:OSM protein, human; D044140:Receptor, Angiotensin, Type 1; D016212:Transforming Growth Factor beta; D053683:Oncostatin M; D008156:Luciferases