Thyroid and glucocorticoid hormones induce expression of lactase-phlorizin hydrolase gene in CDX-2/HNF-1α co-transfected IEC-6 cells.
Thyroid and glucocorticoid hormones and several transcriptional factors such as caudal type homeobox (CDX)-2 and hepatocyte nuclear factor (HNF)-1α are important for the differentiation of small intestinal absorptive cells and the consequent expression of genes related to the digestion/absorption of carbohydrates. In this study, we investigated whether thyroid and glucocorticoid hormones enhanced the expression of lactase-phlorizin hydrolase (LPH) gene, an intestine-specific gene that encodes an enzyme for lactose digestion, in small intestinal stem-like IEC-6 cells co-transfected with CDX-2 and HNF-1α using a retrovirus system. Changes in expression of intestine-specific genes caused by treatment with thyroid and/or glucocorticoid hormones were monitored in empty vector-transfected cells and in CDX-2/HNF-1α co-transfected cells by qRT-PCR. Stable co-transfection with CDX-2 and HNF-1α evoked the expression of the LPH gene in IEC-6 cells. Furthermore, treatment with a thyroid hormone, triiodothyronine, and a glucocorticoid receptor agonist, dexamethasone, significantly enhanced expression of the LPH, CDX-2 and HNF-1α genes in CDX-2/HNF-1α co-transfected IEC-6 cells. These results suggest that thyroid and glucocorticoid hormones synergistically enhance expression of the LPH gene in CDX-2/HNF-1α co-transfected IEC-6 cells.
Laboratory of Nutritional Physiology, Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka 422-8526; Faculty of Education, Art and Science, Food Environment Design Course, Yamagata University, Japan.
Takuji
T
Suzuki
Kazuki
K
Mochizuki
Toshinao
T
Goda
D000818:Animals; D000071616:CDX2 Transcription Factor; D002460:Cell Line; D003907:Dexamethasone / Q000494:pharmacology; D020077:Endogenous Retroviruses / Q000235:genetics; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism*; D005938:Glucocorticoids / Q000494:pharmacology*; D051538:Hepatocyte Nuclear Factor 1-alpha / Q000235:genetics*; D018398:Homeodomain Proteins / Q000235:genetics*; D007422:Intestines / Q000166:cytology; D010694:Lactase-Phlorizin Hydrolase / Q000235:genetics*; D051381:Rats; D060888:Real-Time Polymerase Chain Reaction; D011965:Receptors, Glucocorticoid / Q000819:agonists; D013963:Thyroid Hormones / Q000494:pharmacology*; D015534:Trans-Activators / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics; D014162:Transfection / Q000379:methods; D014284:Triiodothyronine / Q000494:pharmacology
D000071616:CDX2 Transcription Factor; D005938:Glucocorticoids; D051538:Hepatocyte Nuclear Factor 1-alpha; D018398:Homeodomain Proteins; D011965:Receptors, Glucocorticoid; D013963:Thyroid Hormones; D015534:Trans-Activators; D014157:Transcription Factors; D014284:Triiodothyronine; D003907:Dexamethasone; D010694:Lactase-Phlorizin Hydrolase