A high-fat diet inhibits the progression of diabetes mellitus in type 2 diabetic rats.
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.
Ishii
Yukihito
Y
Japan Tobacco Inc., Central Pharmaceutical Research Institute, Takatsuki, Osaka, Japan.
Ohta
Takeshi
T
Sasase
Tomohiko
T
Morinaga
Hisayo
H
Hata
Takahiro
T
Miyajima
Katsuhiro
K
Katusda
Yoshiaki
Y
Masuyama
Taku
T
Shinohara
Masami
M
Kakutani
Makoto
M
Matsushita
Mutsuyoshi
M
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
D001786:Blood Glucose; D004041:Dietary Fats; D007328:Insulin; D052216:Glucagon-Like Peptide 1