Polyamines in sickle cell disease

Abstract

Sickle cell anemia, a chronic hemolytic disease characterized by severe pain and premature death, affects to varying degrees 1% of the world's black population. Although a number of biochemical alterations have previously been associated with this anemia (1), the recent report of a five- to tenfold elevation in blood polyamine levels (2) is especially noteworthy because the polyamines can alter the normal electrokinetic properties of the red blood cell membrane (3). These observations may help explain the abnormalities of the erthrocyte membrane and decreased red cell deformability associated with the sickling phenomenon. The principal polyamines present in eukaryotes are, repectively, the di-, tri-, and tetramines-putrescine, spermidine, and spermine. Their biological function, which is related to their unique charge distribution, is linked to cell growth, division, and differentiation (4). The polyamines also exert direct on membrane stability and permeability (5), as well as modifying the activity of membrane-bound enzymes including acetylcholinesterase (6) and Na, K-ATPase (7). In the present study it is shown that the erythrocyte stroma fraction, obtained from sickle cells, has associated with it abnormally large amounts of spermine. Stroma binding appears to be selective and not directly dependent on either plasma or erythrocyte lysate polyamine concentration.