title: Different sucrose-isomaltase response of Caco-2 cells to glucose and maltose suggests dietary maltose sensing.
abstract: Using the small intestine enterocyte Caco-2 cell model, sucrase-isomaltase (SI, the mucosal α-glucosidase complex) expression and modification were examined relative to exposure to different mono- and disaccharide glycemic carbohydrates. Caco-2/TC7 cells were grown on porous supports to post-confluence for complete differentiation, and dietary carbohydrate molecules of glucose, sucrose (disaccharide of glucose and fructose), maltose (disaccharide of two glucoses α-1,4 linked), and isomaltose (disaccharide of two glucoses α-1,6 linked) were used to treat the cells. qRT-PCR results showed that all the carbohydrate molecules induced the expression of the SI gene, though maltose (and isomaltose) showed an incremental increase in mRNA levels over time that glucose did not. Western blot analysis of the SI protein revealed that only maltose treatment induced a higher molecular weight band (Mw ~245 kDa), also at higher expression level, suggesting post-translational processing of SI, and more importantly a sensing of maltose. Further work is warranted regarding this putative sensing response as a potential control point for starch digestion and glucose generation in the small intestine.
authors.affiliation: Whistler Center for Carbohydrate Research, 745 Agriculture Mall Drive, Purdue University, West Lafayette, IN 47907-2009, USA ; Department of Food Science, Purdue University, West Lafayette, IN 47907-2009, USA.
authors.forename: Min-Wen
authors.initials: MW
authors.lastname: Cheng
authors.affiliation: Whistler Center for Carbohydrate Research, 745 Agriculture Mall Drive, Purdue University, West Lafayette, IN 47907-2009, USA ; Department of Food Science, Purdue University, West Lafayette, IN 47907-2009, USA.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Chegeni
authors.affiliation: Department of Food Science, Purdue University, West Lafayette, IN 47907-2009, USA.
authors.forename: Kee-Hong
authors.initials: KH
authors.lastname: Kim
authors.affiliation: School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, P.R. China.
authors.forename: Genyi
authors.initials: G
authors.lastname: Zhang
authors.affiliation: School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, P.R. China.
authors.forename: Mustapha
authors.initials: M
authors.lastname: Benmoussa
authors.affiliation: USDA/ARS Children's Nutrition Research Center and the Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA ; Department of Chemistry, Universidad Autonoma de San Luis Potosi, San Luis Potosi 78210, Mexico.
authors.forename: Roberto
authors.initials: R
authors.lastname: Quezada-Calvillo
authors.affiliation: USDA/ARS Children's Nutrition Research Center and the Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Buford L
authors.initials: BL
authors.lastname: Nichols
authors.affiliation: Whistler Center for Carbohydrate Research, 745 Agriculture Mall Drive, Purdue University, West Lafayette, IN 47907-2009, USA ; Department of Food Science, Purdue University, West Lafayette, IN 47907-2009, USA.
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Hamaker
keywords: maltose; mucosal α-glucosidases; sensing; small intestine; sucrase-isomaltase