Increased plasma dipeptidyl peptidase IV (DPP IV) activity and decreased DPP IV activity of visceral but not subcutaneous adipose tissue in impaired glucose tolerance rats induced by high-fat or high-sucrose diet.
Several studies have investigated whether dipeptidyl peptidase IV (DPP IV) activity is correlated to the severity of diabetes; however, it remains unclear. To investigate the roles of DPP IV activity in metabolic abnormalities, impaired glucose tolerance rats were produced using a high-fat (HF) or high-sucrose (HS) diet. HF diet-fed rats obviously exhibited impaired glucose tolerance, with increases in subcutaneous and epididymal fat mass, insulin resistance and dyslipidaemia. In rats fed a HS diet rather than a normal diet, lower body weight and fasting blood glucose were observed temporarily in the early period after HS diet feeding; however, impaired glucose tolerance was evoked to some extent with an increase in epididymal fat mass. Both HF and HS diet-fed rats showed significantly higher plasma DPP IV activity than normal diet-fed rats, in the order of HF diet>HS diet>normal diet. HF and HS diets did not significantly affect DPP IV activity and mRNA expression in the kidney. On the other hand, HF, but not HS, diet caused a significant decrease in DPP IV activity in the liver as compared to the control. Of note, both HF and HS diets caused a significant decrease in DPP IV activity in epididymal fat, even though they did not change DPP IV activity in subcutaneous fat. In conclusion, HF or HS diet-induced impaired glucose tolerance with visceral fat accumulation may be interrelated with increased plasma DPP IV activity and decreased DPP IV activity of visceral but not subcutaneous adipose tissue.
Kirino
Yasushi
Y
Department of Human Genetics and Public Health, Institute of Health Biosciences, The University of Tokushima Graduate School, Japan.
Kamimoto
Takayuki
T
Sato
Youichi
Y
Kawazoe
Kazuyoshi
K
Minakuchi
Kazuo
K
Nakahori
Yutaka
Y
D000818:Animals; D001835:Body Weight; D004041:Dietary Fats / Q000008:administration & dosage*; D019422:Dietary Sucrose / Q000008:administration & dosage*; D018819:Dipeptidyl Peptidase 4 / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics; D004435:Eating; D018149:Glucose Intolerance / Q000201:enzymology*; D005951:Glucose Tolerance Test; D050152:Intra-Abdominal Fat / Q000201:enzymology*; D008297:Male; D009928:Organ Specificity; D012313:RNA / Q000096:biosynthesis; D051381:Rats; D011916:Rats, Inbred F344; D050151:Subcutaneous Fat / Q000201:enzymology*
D004041:Dietary Fats; D019422:Dietary Sucrose; D012313:RNA; D018819:Dipeptidyl Peptidase 4