Decreased Nucleoside Transport and hENT1 Transporter Expression in Beta-Thalassemia Major

Arwa Lufti Al-Massaeid, James D. Craik
2009 Medical Principles and Practice  
cells; 102.60 8 3.02 arbitrary units, n = 20, for control cells; p = 0.87). Conclusions: Erythrocytes from ␤ -thalassemia major patients showed decreased uridine transport which was associated with decreased nucleoside transporter expression. The process(es) mediating a selective decrease in hENT1 polypeptides in ␤ -thalassemia major was/were not determined. Abstract Objective: This study investigated nucleoside transport activity and transporter polypeptide expression in erythrocytes from ␤
more » ... alassemia major patients to determine if inhibition of transport activity is a sensitive indicator of oxidative membrane damage. Materials and Methods: Blood samples were obtained from 54 patients, diagnosed as having ␤ -thalassemia major prior to therapeutic transfusion, and 20 normal subjects. Uptake of 3 H-uridine into washed erythrocytes was measured at room temperature using short incubation periods (5 s) and a rapid inhibitor oil stop protocol. Erythrocyte membranes were analyzed by SDS-PAGE and nucleoside (hENT1) and glucose (GLUT-1) transporter polypeptides quantitated on immunoblots. Results: Uridine uptake was significantly lower in ␤ -thalassemic cells than in normal erythrocytes (20.03 8 1.08 pmol/10 8 cells/ 5 s, mean 8 SEM, n = 31, vs. 31.15 8 1.21 pmol/10 8 cells/5 s, n = 20; p ! 0.0001). Expression of hENT1 was significantly lower in ␤ -thalassemic cells (23.90 8 1.01 arbitrary units, n = 54) than in controls (101.20 8 2.43 arbitrary units, n = 20; p ! 0.001) but expression of GLUT-1 was not changed appreciably (101.80 8 2.43 arbitrary units, n = 54, for thalassemic
doi:10.1159/000204347 pmid:19349719 fatcat:i4xh6ujvdzgxrjh5ytrqp5rwne