title: Genetic interaction between hyperglycemic QTLs is manifested under a high calorie diet in OLETF-derived congenic rats.
abstract: The condition of hyperglycemia results from multiple genetic and environmental factors. In recent years much progress has been made with regards to the search for candidate genes involved in the expression of various common diseases including type 2 diabetes. However less is known about the specific genetic and environmental connections that are important for the development of the disease. In the present study, we used hyperglycemic congenic rats to address this issue. When given a normal diet, two hyperglycemic QTLs (quantitative trait locus), Nidd2/of and Nidd10/of, showed mild obesity and/or increased blood glucose in the oral glucose tolerance test. In a double congenic strain possessing both loci, these indices were not significantly different from those of either single congenic strain. In contrast, the double congenic strain fed a high-calorie diet showed significantly greater body weight than the single congenic strains or normoglycemic control rats. Although postprandial glucose levels of the double congenic rat were not further aggravated even on the high fat diet, it was notable that the postprandial insulin levels were drastically elevated. From these results, we constructed a novel model animal especially for the study of prediabetic hyperinsulemia, in which two QTLs and an additional dietary condition are involved. This may help to shed light on the genetic basis and gene-to-diet interaction during the early stage of type 2 diabetes.
authors.affiliation: Division for Animal Research Resources, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503, Japan.
authors.forename: Tomoe
authors.initials: T
authors.lastname: Fukumura
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kose
authors.forename: Chiyo
authors.initials: C
authors.lastname: Takeda
authors.forename: Yuko
authors.initials: Y
authors.lastname: Kurita
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Ochiai
authors.forename: Takahisa
authors.initials: T
authors.lastname: Yamada
authors.forename: Kozo
authors.initials: K
authors.lastname: Matsumoto
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics*; D004195:Disease Models, Animal; D002149:Energy Intake; D005951:Glucose Tolerance Test; D006943:Hyperglycemia / Q000235:genetics*; D006946:Hyperinsulinism / Q000235:genetics; D007328:Insulin; D020412:Multifactorial Inheritance; D040641:Quantitative Trait Loci; D051381:Rats; D020334:Rats, Inbred OLETF; D015430:Weight Gain
chemical_list: D001786:Blood Glucose; D007328:Insulin