title: A high-fat diet inhibits the progression of diabetes mellitus in type 2 diabetic rats.
abstract: It is well known that rats and mice, when fed a high-fat diet, develop obesity associated with abnormal glycolipid metabolism. In this study, we investigated the effects of a high-fat diet on a diabetic rat model, Spontaneously Diabetic Torii (SDT), which develops diabetes due to decreased insulin production and secretion with age. We hypothesized that a high-fat diet would accelerate the induction of diabetes in this model. The SDT rats were divided into 2 groups, which were fed a high-fat diet or standard diet for 16 weeks. The group fed a high-fat diet developed obesity, hyperinsulinemia, and hyperlipidemia until 16 weeks of age. Before 16 weeks of age, hyperglycemia accompanied by hypoinsulinemia developed in the group on a standard diet, but serum glucose levels were comparable in both groups. After 16 weeks of age, the group on a standard diet showed an increase in serum glucose levels and a decrease in serum insulin levels. Unexpectedly, in the group on the high-fat diet, we observed a suppressed of the progression of hyperglycemia/hypoinsulinemia. Histopathological observation revealed more pancreatic beta cells in the group on the high-fat diet. This study suggests that feeding SDT rats a high-fat diet induces obesity, hyperinsulinemia, and hyperlipidemia, but not hyperglycemia, until 16 weeks of age. Thereafter, age-dependent progress of hyperglycemia and hypoinsulinemia was delayed by a high-fat diet. The hyperfunction of pancreatic beta cells induced by a high-fat diet before the onset of hyperglycemia appears to suppress development of hyperglycemia/hypoinsulinemia.
authors.affiliation: Japan Tobacco Inc., Central Pharmaceutical Research Institute, Takatsuki, Osaka, Japan.
authors.forename: Yukihito
authors.initials: Y
authors.lastname: Ishii
authors.forename: Takeshi
authors.initials: T
authors.lastname: Ohta
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Sasase
authors.forename: Hisayo
authors.initials: H
authors.lastname: Morinaga
authors.forename: Takahiro
authors.initials: T
authors.lastname: Hata
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Miyajima
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Katusda
authors.forename: Taku
authors.initials: T
authors.lastname: Masuyama
authors.forename: Masami
authors.initials: M
authors.lastname: Shinohara
authors.forename: Makoto
authors.initials: M
authors.lastname: Kakutani
authors.forename: Mutsuyoshi
authors.initials: M
authors.lastname: Matsushita
mesh_terms: D000273:Adipose Tissue / Q000473:pathology; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D001835:Body Weight; D003924:Diabetes Mellitus, Type 2 / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D004032:Diet; D004041:Dietary Fats / Q000008:administration & dosage*; D002149:Energy Intake; D052216:Glucagon-Like Peptide 1 / Q000097:blood; D005951:Glucose Tolerance Test; D007328:Insulin / Q000097:blood; D008297:Male; D010179:Pancreas / Q000473:pathology; D011507:Proteinuria / Q000652:urine; D051381:Rats
chemical_list: D001786:Blood Glucose; D004041:Dietary Fats; D007328:Insulin; D052216:Glucagon-Like Peptide 1