Elevated Levels of Sphingolipids in Type II (a+b) Hyperlipoproteinemia

The levels of sphingomyelin, neutral glycosphingolipids and gangliosides were studied in normal and type II hyperproteinemic plasmas. Sphingomyelin levels were elevated and there was an excellent correlation between cholesterol and sphingomyelin (r=0.86). The correlation between cholesterol and the remainder of the phospholipids (i.e., total phospholipid minus sphingomyelin) was significantly less than that between cholesterol and sphingomyelin. The other sphingolipids were also elevated. The four neutral glycosphingolipids were from 37 to 100 percent higher than normal (p<0.05). Hematoside (GM3) was increased 17% above normal (p<0.05). The concept of a specific involvement of sphingolipid metabolism in type II (a and b) hyperlipoproteinemia is proposed.