title: Microgram amounts of abscisic acid in fruit extracts improve glucose tolerance and reduce insulinemia in rats and in humans.
abstract: 2-Cis,4-trans-abscisic acid (ABA) is a plant hormone that is present also in animals. Several lines of evidence suggest that ABA contributes to the regulation of glycemia in mammals: nanomolar ABA stimulates insulin release from β-pancreatic cells and glucose transporter-4-mediated glucose uptake by myoblasts and adipocytes in vitro; plasma ABA increases in normal human subjects, but not in diabetic patients, after a glucose load for an oral glucose tolerance test (OGTT). The presence of ABA in fruits prompted an exploration of the bioavailability of dietary ABA and the effect of ABA-rich fruit extracts on glucose tolerance. Rats underwent an OGTT, with or without 1 µg/kg ABA, either synthetic or present in a fruit extract. Human volunteers underwent an OGTT or a standard breakfast and lunch, with or without a fruit extract, yielding an ABA dose of 0.85 or 0.5 µg/kg, respectively. Plasma glucose, insulin, and ABA were measured at different time points. Oral ABA at 0.5-1 µg/kg significantly lowered glycemia and insulinemia in rats and in humans. Thus, the glycemia-lowering effect of low-dose ABA in vivo does not depend on an increased insulin release. Low-dose ABA intake may be proposed as an aid to improving glucose tolerance in patients with diabetes who are deficient in or resistant to insulin.
authors.affiliation: *Department of Experimental Medicine, Section of Biochemistry and Center of Excellence for Biomedical Research, and Department of Internal Medicine, University of Genoa, Genoa, Italy; and Animal Facility, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Universitaria San Martino, Istituto Scientifico Tumori, Genoa, Italy mirko.magnone@unige.it ezocchi@unige.it.
authors.forename: Mirko
authors.initials: M
authors.lastname: Magnone
authors.affiliation: *Department of Experimental Medicine, Section of Biochemistry and Center of Excellence for Biomedical Research, and Department of Internal Medicine, University of Genoa, Genoa, Italy; and Animal Facility, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Universitaria San Martino, Istituto Scientifico Tumori, Genoa, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Ameri
authors.affiliation: *Department of Experimental Medicine, Section of Biochemistry and Center of Excellence for Biomedical Research, and Department of Internal Medicine, University of Genoa, Genoa, Italy; and Animal Facility, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Universitaria San Martino, Istituto Scientifico Tumori, Genoa, Italy.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Salis
authors.affiliation: *Department of Experimental Medicine, Section of Biochemistry and Center of Excellence for Biomedical Research, and Department of Internal Medicine, University of Genoa, Genoa, Italy; and Animal Facility, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Universitaria San Martino, Istituto Scientifico Tumori, Genoa, Italy.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Andraghetti
authors.affiliation: *Department of Experimental Medicine, Section of Biochemistry and Center of Excellence for Biomedical Research, and Department of Internal Medicine, University of Genoa, Genoa, Italy; and Animal Facility, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Universitaria San Martino, Istituto Scientifico Tumori, Genoa, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Emionite
authors.affiliation: *Department of Experimental Medicine, Section of Biochemistry and Center of Excellence for Biomedical Research, and Department of Internal Medicine, University of Genoa, Genoa, Italy; and Animal Facility, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Universitaria San Martino, Istituto Scientifico Tumori, Genoa, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Murialdo
authors.affiliation: *Department of Experimental Medicine, Section of Biochemistry and Center of Excellence for Biomedical Research, and Department of Internal Medicine, University of Genoa, Genoa, Italy; and Animal Facility, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Universitaria San Martino, Istituto Scientifico Tumori, Genoa, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: De Flora
authors.affiliation: *Department of Experimental Medicine, Section of Biochemistry and Center of Excellence for Biomedical Research, and Department of Internal Medicine, University of Genoa, Genoa, Italy; and Animal Facility, Istituto di Ricovero e Cura a Carattere Scientifico, Azienda Ospedaliera Universitaria San Martino, Istituto Scientifico Tumori, Genoa, Italy mirko.magnone@unige.it ezocchi@unige.it.
authors.forename: Elena
authors.initials: E
authors.lastname: Zocchi
mesh_terms: D000040:Abscisic Acid / Q000302:isolation & purification / Q000494:pharmacology*; D000328:Adult; D000818:Animals; D005260:Female; D005638:Fruit / Q000737:chemistry*; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000097:blood*; D008297:Male; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D055815:Young Adult
chemical_list: D007328:Insulin; D010936:Plant Extracts; D000040:Abscisic Acid
keywords: OGTT; apricots; plasma glucose; plasma insulin; standard B&L