Decreased nucleoside transport and hENT1 transporter expression in beta-thalassemia major.

This study investigated nucleoside transport activity and transporter polypeptide expression in erythrocytes from beta-thalassemia major patients to determine if inhibition of transport activity is a sensitive indicator of oxidative membrane damage. Blood samples were obtained from 54 patients, diagnosed as having beta-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. Uridine uptake was significantly lower in beta-thalassemic cells than in normal erythrocytes (20.03 +/- 1.08 pmol/10(8) cells/ 5 s, mean +/- SEM, n = 31, vs. 31.15 +/- 1.21 pmol/10(8) cells/5 s, n = 20; p < 0.0001). Expression of hENT1 was significantly lower in beta-thalassemic cells (23.90 +/- 1.01 arbitrary units, n = 54) than in controls (101.20 +/- 2.43 arbitrary units, n = 20; p < 0.001) but expression of GLUT-1 was not changed appreciably (101.80 +/- 2.43 arbitrary units, n = 54, for thalassemic cells; 102.60 +/- 3.02 arbitrary units, n = 20, for control cells; p = 0.87). Erythrocytes from beta-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 beta-thalassemia major was/were not determined. Copyright 2009 S. Karger AG, Basel.

Citation

Arwa Lufti Al-Massaeid, James D Craik. Decreased nucleoside transport and hENT1 transporter expression in beta-thalassemia major. Medical principles and practice : international journal of the Kuwait University, Health Science Centre. 2009;18(3):180-6

Mesh Tags

Substances

PMID: 19349719

search → result