title: L-glutamine therapy reduces endothelial adhesion of sickle red blood cells to human umbilical vein endothelial cells.
abstract: BACKGROUND
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Medicine, Harbor-UCLA Medical Center, UCLA School of Medicine, Torrance, CA, USA. ysniihara@msn.com
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Niihara
authors.forename: Neil M
authors.initials: NM
authors.lastname: Matsui
authors.forename: Yamin M
authors.initials: YM
authors.lastname: Shen
authors.forename: Dean A
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authors.lastname: Akiyama
authors.forename: Cage S
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authors.lastname: Johnson
authors.forename: M Alenor
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authors.lastname: Sunga
authors.forename: John
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authors.lastname: Magpayo
authors.forename: Stephen H
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authors.forename: Vijay K
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authors.forename: Seong Ho
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authors.forename: Kouichi R
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