Increased fat absorption and impaired fat clearance cause postprandial hypertriglyceridemia in Spontaneously Diabetic Torii rat.
In diabetes, postprandial hyperlipidemia is recognized as a risk factor for premature atherosclerosis and following cardiovascular disease. In the present study, features of fat absorption and clearance were examined to clarify the lipid metabolism of Spontaneously Diabetic Torii (SDT) rats. Olive oil was orally administered to evaluate increase of blood triglyceride (TG) level. Mesenteric lymph chylomicron TG was also measured. mRNAs of enzymes and transfer protein related to TG metabolism and histopathological changes were evaluated. In an oil loading test, elevation of TG in plasma and lymph chylomicron was increased in SDT rats. Interestingly, SDT rats showed elevation of plasma TG after oil loading and relatively low epididymal fat lipoprotein lipase (LPL) mRNA expression even at the pre-diabetic state without increase of TG absorption from intestine. In the diabetic state, intestines of SDT rats were hypertrophic and expressed mRNAs of enzymes and transfer protein related to TG absorption highly. From these results, it seems that intestinal abnormalities related to hypoinsulinemia/hyperglycemia cause postprandial hypertriglyceridemia in SDT rats. In addition, our findings suggest that SDT rats have impaired lipid catabolism antecedent to hypoinsulinemia/hyperglycemia. These characteristics of SDT rats can be useful in studies of diabetic hypertriglyceridemia and TG metabolism.
Sasase
Tomohiko
T
Japan Tobacco Inc, Central Pharmaceutical Research Institute, Biological/Pharmacological Research Laboratories, Takatsuki, Osaka, Japan. tomohiko.sasase@ims.jti.co.jp
Morinaga
Hisayo
H
Yamamoto
Hiromi
H
Ogawa
Naoto
N
Matsui
Kenichi
K
Miyajima
Katsuhiro
K
Kawai
Takashi
T
Mera
Yasuko
Y
Masuyama
Taku
T
Shinohara
Masami
M
Ohta
Takeshi
T
Matsushita
Mutsuyoshi
M
D000818:Animals; D001835:Body Weight; D002914:Chylomicrons / Q000378:metabolism; D003920:Diabetes Mellitus / Q000235:genetics* / Q000378:metabolism; D004041:Dietary Fats / Q000493:pharmacokinetics*; D002149:Energy Intake; D006943:Hyperglycemia / Q000235:genetics; D007408:Intestinal Absorption / Q000502:physiology*; D008055:Lipids / Q000493:pharmacokinetics*; D008297:Male; D000069463:Olive Oil; D010938:Plant Oils / Q000493:pharmacokinetics; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D011922:Rats, Mutant Strains; D014280:Triglycerides / Q000378:metabolism
D002914:Chylomicrons; D004041:Dietary Fats; D008055:Lipids; D000069463:Olive Oil; D010938:Plant Oils; D012333:RNA, Messenger; D014280:Triglycerides