Life Sci. 1998 ; 63(12): 995-1003.

Proliferative effects of oxidized low-density lipoprotein on vascular smooth muscle cells: role of dietary habits.

Lähteenmäki TA, Korpela R, Tikkanen MJ, Karjala K, Laakso J, Solatunturi E, Vapaatalo H.

Institute of Biomedicine, Department of Pharmacology and Toxicology, University of Helsinki, Finland. tuula.lahteenmaki@helsinki.fi

The effects were studied of native, partially-oxidized and totally-oxidized human low-density lipoprotein (LDL) on the proliferation of cultured rat aortic smooth muscle cells (VSMC), measured as an altered DNA synthesis. The LDL was obtained from three different human long-term diet groups (a control diet rich in saturated fats, a vegetarian diet, and a fish diet). The oxidized LDLs were prepared by oxidizing the LDL with copper sulfate. The DNA synthesis was measured by [3H]-thymidine incorporation into the DNA. The partially-oxidized LDL was the most potent promoter of DNA synthesis compared to the native or totally-oxidized LDL of the same diet group. The partially-oxidized LDL had a true mitogenic effect in the absence of exogenous growth factors. The native and totally-oxidized LDL induced a significant increase in DNA synthesis, if they were obtained from the fish diet group. This study suggests an enhanced proliferative effect of partially-oxidized LDL on VSMC growth.