Akiko Fukushima, Ph.D.

Molecular Nutrition

The Laboratory of Molecular Nutrition was established in 1990 with the goal of elucidating nutritional phenomena in molecular terms. The major focus of research has been calcium absorption in the intestine, as calcium is the only nutrient lacking in the Japanese diet. We have been investigating the regulation mechanism of genes involved in calcium absorption in the intestine to elucidate a nutritional counteraction against osteoporosis.
The genes for epithelial calcium channel (TRPV6), which is involved in the step of calcium entry into the mucosal cell, calcium binding protein (CaBP, calbindin D9k), which effects the diffusion of calcium across the cytoplasm of enterocytes, and Ca-ATPase (PMCA1), which is involved in the step of extrusion into the extracellular fluid at the basolateral side, have been characterized, and the regulation mechanism of expression of these genes has been studied with special attention to dietary effects. Experiments using rats or cultured caco-2 cells are currently being conducted.

Fukushima, A., Aizaki, Y. and Sakuma K.: Short-chain fatty acids induce intestinal TRPV6 expression in rats and Caco-2 cells. J. Nutr., 139, 20-25 (2009)

Fukushima, A., Ohta, A., Sakai, K. & Sakuma, K.: Expression of calbindin-D9k, VDR and Cdx-2 messenger RNA in the process by which fructooligosaccharides increase calcium absorption in rats. J. Nutr. Sci. Vitaminol. 51, 426-432 (2005)

Yamakawa, M., Fukuhisma, A., Sakuma, K., Yanagisawa, Y. and Kagawa, Y.: Serotonin transporter polymorphisms affect human blood glucose control. Biochem. Biophys. Res. Commun. 334, 1165-1171 (2005)