title: Rice (Oryza sativa japonica) Albumin Suppresses the Elevation of Blood Glucose and Plasma Insulin Levels after Oral Glucose Loading.
abstract: The suppressive effect of rice albumin (RA) of 16 kDa on elevation of blood glucose level after oral loading of starch or glucose and its possible mechanism were examined. RA suppressed the increase in blood glucose levels in both the oral starch tolerance test and the oral glucose tolerance test. The blood glucose concentrations 15 min after the oral administration of starch were 144 ± 6 mg/dL for control group and 127 ± 4 mg/dL for RA 200 mg/kg BW group, while those after the oral administration of glucose were 157 ± 7 mg/dL for control group and 137 ± 4 mg/dL for RA 200 mg/kg BW group. However, in the intraperitoneal glucose tolerance test, no significant differences in blood glucose level were observed between RA and the control groups, indicating that RA suppresses the glucose absorption from the small intestine. However, RA did not inhibit the activity of mammalian α-amylase. RA was hydrolyzed to an indigestible high-molecular-weight peptide (HMP) of 14 kDa and low-molecular-weight peptides by pepsin and pancreatin. Furthermore, RA suppressed the glucose diffusion rate through a semipermeable membrane like dietary fibers in vitro. Therefore, the indigestible HMP may adsorb glucose and suppress its absorption from the small intestine.
authors.affiliation: Department of Chemistry and Life Science, Nihon University , 1866 Kameino, Fujisawa-shi 252-0880, Japan.
authors.forename: Shigenobu
authors.initials: S
authors.lastname: Ina
authors.affiliation: Department of Chemistry and Life Science, Nihon University , 1866 Kameino, Fujisawa-shi 252-0880, Japan.
authors.forename: Kazumi
authors.initials: K
authors.lastname: Ninomiya
authors.affiliation: Department of Chemistry and Life Science, Nihon University , 1866 Kameino, Fujisawa-shi 252-0880, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Mogi
authors.affiliation: Department of Chemistry and Life Science, Nihon University , 1866 Kameino, Fujisawa-shi 252-0880, Japan.
authors.forename: Ayumu
authors.initials: A
authors.lastname: Hase
authors.affiliation: Department of Chemistry and Life Science, Nihon University , 1866 Kameino, Fujisawa-shi 252-0880, Japan.
authors.forename: Toshiki
authors.initials: T
authors.lastname: Ando
authors.affiliation: Department of Chemistry and Life Science, Nihon University , 1866 Kameino, Fujisawa-shi 252-0880, Japan.
authors.forename: Narumi
authors.initials: N
authors.lastname: Matsukaze
authors.affiliation: Department of Chemistry and Life Science, Nihon University , 1866 Kameino, Fujisawa-shi 252-0880, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Ogihara
authors.affiliation: Department of Chemistry and Life Science, Nihon University , 1866 Kameino, Fujisawa-shi 252-0880, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Akao
authors.affiliation: Department of Food Science and Nutrition, Kyoritsu Women's University , 2-2-1 Hitotsubashi, Chiyoda-ku, Tokyo 101-8347, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kumagai
authors.affiliation: Department of Chemistry and Life Science, Nihon University , 1866 Kameino, Fujisawa-shi 252-0880, Japan.
authors.forename: Hitomi
authors.initials: H
authors.lastname: Kumagai
mesh_terms: D000418:Albumins / Q000378:metabolism*; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D004063:Digestion; D005753:Gastric Mucosa / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D005951:Glucose Tolerance Test; D007328:Insulin / Q000097:blood*; D008297:Male; D012275:Oryza / Q000737:chemistry / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*; D019518:Postprandial Period; D051381:Rats; D017208:Rats, Wistar; D000516:alpha-Amylases / Q000378:metabolism
chemical_list: D000418:Albumins; D001786:Blood Glucose; D007328:Insulin; D010940:Plant Proteins; D000516:alpha-Amylases; D005947:Glucose
keywords: digestibility; glucose adsorption; intraperitoneal glucose tolerance test; oral glucose and starch tolerance tests; rice albumin