Dietary Palmitoleic Acid Attenuates Atherosclerosis Progression and Hyperlipidemia in Low-Density Lipoprotein Receptor-Deficient Mice.

Scope Palmitoleic acid (palmitoleate; C16:1 n-7), an omega-7 monounsaturated fatty acid (MUFA) found in plants and marine sources, has been shown to favorably modulate lipid and glucose metabolism. However, its impact on atherosclerosis has not been examined in detail. Methods and Results LDL receptor knock out (LDLR-KO) mice are fed a Western diet supplemented with 5% (w/w) palmitoleate concentrate, oleic-rich olive oil, or none (control) for 12 weeks. Dietary palmitoleate increases hepatic C16:1 levels, improves plasma and hepatic lipid/lipoprotein profiles (approximate to 40% decrease in triglycerides), and reduces the atherosclerotic plaque area by approximate to 45% compared with control or olive oil group (p < 0.05). These favorable changes are accompanied by the downregulation of key genes, such as Srebp1c, Scd1, Il-1 beta, and Tnf alpha. ApoB-depleted plasma from mice fed palmitoleate has increased cholesterol efflux capacity by 20% from ABCA1-expressing cells (p < 0.05). A beneficial effect of palmitoleate on glucose metabolism (54% decreased in HOMA-IR, p < 0.05) is also observed. Conclusions Dietary-supplemented palmitoleate reduces atherosclerosis development in LDLR-KO mice, and is associated with improvement of lipid and glucose metabolism and favorable changes in regulatory genes involved in lipogenesis and inflammation. These findings imply the potential role of dietary palmitoleate in the prevention of cardiovascular disease and diet-induced metabolic disorders.