Mechanism of the antithrombotic effect of dietary diacylglycerol in atherogenic mice.
BACKGROUND
We have shown earlier that diacylglycerol (DAG) but not triacylglycerol (TAG) inhibited thrombus formation. The aim of the present study was to investigate the mechanism of this antithrombotic effect of DAG.


METHODS
Four different diets, the (1) Western-style high-fat diet (HFD) containing 20% lipid and 0.05% cholesterol (w/w), (2) TAG-rich and (3) DAG-rich HFDs containing 20% lipid and 0.05% cholesterol, but all lipid replaced by TAG or DAG oil with very similar fatty acid composition and the (4) Japanese-style low-fat diet (LFD) containing 7% oil but no cholesterol were given to apolipoprotein E and low-density lipoprotein (LDL) receptor double-deficient mice. Atherogenicity was assessed by morphology, mapping the whole aorta and measuring the total area of lipid-stained lesions. Endothelial function was measured by the flow-mediated vasodilation test. Platelet reactivity was assessed from native blood sample by a shear-induced platelet function test (hemostatometry). Serum lipoprotein profile was measured by HPLC.


RESULTS
Both the Western-style and the TAG-rich HFDs have accelerated atherosclerosis. In contrast, DAG-rich HFD inhibited the atherosclerotic process to an extent comparable with the Japanese-style LFD. There was no significant difference in platelet and coagulant activity between the studied diet groups. DAG-rich but not the TAG-rich HFD significantly suppressed serum LDL cholesterol level.


CONCLUSIONS
The present findings suggest that the mechanism of antithrombotic and anti-atherogenic effect of DAG may involve the protection of the vascular endothelium from injury and lowered serum LDL cholesterol.
Ijiri
Yoshinobu
Y
Laboratory of Physiology, Faculty of Nutrition, Kobe Gakuin University, Kobe, Japan.
Naemura
Aki
A
Yamashita
Tsutomu
T
Ikarugi
Hideo
H
Meguro
Shinichi
S
Tokimitsu
Ichiro
I
Yamamoto
Junichiro
J
D000818:Animals; D001057:Apolipoproteins E / Q000172:deficiency; D050197:Atherosclerosis / Q000188:drug therapy* / Q000473:pathology / Q000517:prevention & control; D008078:Cholesterol, LDL / Q000097:blood; D004032:Diet; D019587:Dietary Supplements; D004075:Diglycerides / Q000008:administration & dosage* / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000187:drug effects; D005227:Fatty Acids; D005343:Fibrinolytic Agents / Q000008:administration & dosage / Q000494:pharmacology; D008055:Lipids; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D010979:Platelet Function Tests; D011973:Receptors, LDL / Q000172:deficiency; D014664:Vasodilation / Q000187:drug effects
D001057:Apolipoproteins E; D008078:Cholesterol, LDL; D004075:Diglycerides; D005227:Fatty Acids; D005343:Fibrinolytic Agents; D008055:Lipids; D011973:Receptors, LDL