Dataset Information

Selective reduction in the sphingomyelin content of atherogenic lipoproteins inhibits their retention in murine aortas and the subsequent development of atherosclerosis.

ABSTRACT:

Objective

We used the sphingomyelin (SM) synthase 2 (Sms2) gene knockout (KO) approach to test our hypothesis that selectively decreasing plasma lipoprotein SM can play an important role in preventing atherosclerosis.

Methods and results

The sphingolipid de novo synthesis pathway is considered a promising target for pharmacological intervention in atherosclerosis. However, its potential is hampered because the substance's atherogenic mechanism is not completely understood. We prepared Sms2 and apolipoprotein E (Apoe) double-KO mice. They showed a significant decrease in plasma lipoprotein SM levels (35%, P<0.01) and a significant increase in ceramide and dihydroceramide levels (87.5% and 27%, respectively; P<0.01) but no significant changes in other tested sphingolipids, cholesterol, and triglyceride. Non-high-density lipoproteins from the double-KO mice showed a reduction of SM, but not cholesterol, and displayed less tendency toward aortic sphingomyelinase-mediated lipoprotein aggregation in vitro and retention in aortas in vivo when compared with controls. More important, at the age of 19 weeks, Sms2 KO/Apoe KO mice showed a significant reduction in atherosclerotic lesions of the aortic arch and root (52%, P<0.01) compared with controls. The Sms2 KO/Apoe KO brachiocephalic artery contained significantly less SM, ceramide, free cholesterol, and cholesteryl ester (35%, 32%, 58%, and 60%, respectively; P<0.01) than that of the Apoe KO brachiocephalic artery.

Conclusions

Decreasing plasma SM levels through decreasing SMS2 activity could become a promising treatment for atherosclerosis.

SUBMITTER: Fan Y

PROVIDER: S-EPMC3426833 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Publications

Selective reduction in the sphingomyelin content of atherogenic lipoproteins inhibits their retention in murine aortas and the subsequent development of atherosclerosis.

Fan Yifan Y Shi Fujun F Liu Jing J Dong Jibin J Bui Hai H HH Peake David A DA Kuo Ming-Shang MS Cao Guoqing G Jiang Xian-Cheng XC

Arteriosclerosis, thrombosis, and vascular biology 20100902 11

<h4>Objective</h4>We used the sphingomyelin (SM) synthase 2 (Sms2) gene knockout (KO) approach to test our hypothesis that selectively decreasing plasma lipoprotein SM can play an important role in preventing atherosclerosis.<h4>Methods and results</h4>The sphingolipid de novo synthesis pathway is considered a promising target for pharmacological intervention in atherosclerosis. However, its potential is hampered because the substance's atherogenic mechanism is not completely understood. We prep ...[more]

PMID: 20814016

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Dataset Information

Selective reduction in the sphingomyelin content of atherogenic lipoproteins inhibits their retention in murine aortas and the subsequent development of atherosclerosis.

Objective

Methods and results

Conclusions

Publications

Selective reduction in the sphingomyelin content of atherogenic lipoproteins inhibits their retention in murine aortas and the subsequent development of atherosclerosis.

Similar Datasets

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