[Growth factors in the serum in patients with Werner's syndrome]

Premature development of atherosclerosis is a fatal complication together with cancer in patients with Werner' syndrome, a known syndrome of premature aging. Proliferation of arterial smooth muscle cells (SMC) is a key event in the formation of atherosclerosis. This paper studied the serum growth promoting activity of Werner's syndrome in cultured rabbit aortic SMC. Serum of cases of Werner's syndrome showed significantly higher growth-promoting activities than those of age-matched controls. The levels of serum growth hormone, plasma somatomedin C, and urine epidermal growth factor were not increased in Werner's syndrome. The level of serum insulin was generally increased in Werner's syndrome. However, there was no correlation between serum insulin level and growth promoting activity, and the effective dose of insulin for the promotion of SMC growth was ten thousand times higher than that contained in the serum. The above results suggest that elevated serum growth-promoting activity in Werner's syndrome is in part responsible for the premature atherosclerosis and that this elevated activity is derived from either platelet derived growth factor or an unknown growth factor(s) contained in the serum.