Lactase gene transcription is activated in response to hypoxia in intestinal epithelial cells.

摘要: Lactase-phlorizin hydrolase, a brush-border membrane disaccharidase, is marker of intestinal epithelial cell differentiation and digestive function. The intestine susceptible to conditions hypoxia resulting from vascular perfusion deficits. We hypothesized that lactase gene induction may provide mechanism efficiently increase nutrient energy substrates during gut hypoxia. These studies sought characterize expression the in response role for hypoxia-inducible factor (HIF-1) mediating hypoxic response. Microarray analysis confirmatory RT-PCR identified 4-fold mRNA abundance Caco-2 cells exposed Lactase promoter activity was similarly induced by stably transfected with 2.0-kb 5' flanking region rat linked reporter gene. Transient cotransfection HIF-1alpha beta stimulated 2.4- 3.5-fold under normoxia hypoxia, respectively. conclude HIF-1 can activate Induction transcription represent an adaptive