L-Glutamine therapy reduces endothelial adhesion of sickle red blood cells to human umbilical vein endothelial cells
1 Department of Medicine, Harbor-UCLA Medical Center, UCLA School of Medicine, Torrance, CA USA
2 Department of Pediatrics, Harbor-UCLA Medical Center, UCLA School of Medicine, Torrance, CA USA
3 Department of Medicine, San Francisco General Hospital, UCSF School of Medicine, San Francisco, CA USA
4 Department of Biochemistry, USC Keck School of Medicine, Los Angeles CA USA
5 Medicine/Hematology, USC Keck School of Medicine, Los Angeles CA USA
BMC Blood Disorders 2005, 5:4 doi:10.1186/1471-2326-5-4Published: 25 July 2005
We have previously demonstrated that therapy with orally administered L-glutamine improves nicotinamide adenosine dinucleotide (NAD) redox potential of sickle red blood cells (RBC). On further analysis of L-glutamine therapy for sickle cell anemia patients, the effect of L-glutamine on adhesion of sickle RBC to human umbilical vein endothelial cells (HUVEC) was examined.
The first part of the experiment was conducted with the blood samples of the 5 adult sickle cell anemia patients who had been on L-glutamine therapy for at least 4 weeks on a dosage of 30 grams per day compared to those of patient control group. In the second part of the experiment 6 patients with sickle cell anemia were studied longitudinally. Five of these patients were treated with oral L-glutamine 30 grams daily and one was observed without treatment as the control. t-test and paired t-test were used for determination of statistical significance in cross-sectional and longitudinal studies respectively.
In the first study, the mean adhesion to endothelial cells with the autologous plasma incubated cells were 0.97 ± 0.45 for the treated group and 1.91 ± 0.53 for the nontreated group (p < 0.02). Similarly with lipopolysaccharide (LPS) incubated cells the mean adhesion to endothelial cells were 1.39 ± 0.33 for the treated group and 2.80 ± 0.47 for the untreated group (p < 0.001). With the longitudinal experiment, mean decrease in the adhesion to endothelial cells was 1.13 ± 0.21 (p < 0.001) for the 5 treated patients whereas the control patient had slight increase in the adhesion to endothelial cells.
In these studies, oral L-glutamine administration consistently resulted in improvement of sickle RBC adhesion to HUVEC. These data suggest positive physiological effects of L-glutamine in sickle cell disease.