Science / Medicine : Study on Clogged Arteries

Another study of transgenic mice has provided the first direct proof that high-density lipoproteins--HDL, the so-called “good cholesterol”--can protect against atherosclerosis, the buildup of fatty deposits in blood vessels. Such buildups clog the vessels, producing heart attacks. Epidemiological studies in humans have shown that high levels of HDL are associated with low levels of atherosclerosis, but scientists were not sure whether the high HDL levels produced the effect or were themselves the result of some unknown factor that also protected against atherosclerosis.

Molecular biologist Edward M. Rubin and his colleagues at the Lawrence Berkeley Laboratory used genetic engineering techniques to insert the gene for HDL into a strain of mice that spontaneously develop atherosclerosis when fed a high-fat diet. They reported last week in the British journal Nature that the transgenic mice showed little or no buildup of fatty deposits after 18 weeks on a high-fat diet.

The results, Rubin said, provide strong proof that interventions that increase levels of HDL in humans will reduce the risk of heart disease.