In vitro effects of aqueous extracts of Zanthxylummacrophyla roots on adenosine triphosphatases from human erythrocytes of different genotypes

The in vitro effects of aqueous extracts of Zanthoxylum macrophylla  roots on the activities of three ATPases (Na+, K+- ; Ca2+- ; and Mg2+-ATPases) were investigated in membrane preparations from human erythrocytes of HbAA, HbAS and HbSS bloods. The activities of these membrane-bound enzymes were determined in the presence of varying concentrations of the plant extract. The results indicated that for Na+, K+- and Ca2+-ATPases, a dose-dependent activation of the three enzymes by the aqueous plant extract occurred. The trend for the different genotypes was HbSS>HbAS>HbAA. The activations were significant (p<0.05) when compared with activities obtained in the absence of the plant extract. Phenylalanine, a known anti-sickling agent, at varying concentrations (200-800μM) produced similar activating effect. In contrast, the extract inhibited the Mg2+-ATPase activity in a dose-dependent manner with a trend of HbSS>HbAS>HbAA. The inhibitions seen were significant (p<0.05) in comparison with activities in the absence of the plant extract. Phenylalanine produced similar effect for Mg2+-ATPase. These findings in this study suggest that differences in the ATPases of the different genotypes may account for the reports of other workers on the involvement of ion transport as a factor in the physiological manifestation of sickle cell disease. The findings are also significant to an understanding of the molecular basis for the use of the aqueous extract of Z. macrophylla roots in the management of sickle cell disease.