Submitted to: American Journal of Clinical Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/19/2002
Publication Date: 9/20/2002
Citation: BADALOO,A., REID,M., FORRESTER,T., HEIRD,W.C., JAHOOR,F. ., CYSTEINE SUPPLEMENTATION IMPROVES THE ERYTHROCYTE GLUTATHIONE SYNTHESIS RATE IN CHILDREN WITH SEVERE EDEMATOUS MALNUTRITION, AMERICAN JOURNAL OF CLINICAL NUTRITION. 2002. v. 76(3). p. 646-652. Interpretive Summary: It is believed that the organs of severely malnourished children malfunction because harmful compounds called oxidants injure the tissues in these organs. In a healthy person oxidants are made harmless because another compound called glutathione neutralizes them. Glutathione is made from three amino acids that we get from the protein we eat in our food. We found that malnourished children were not making enough glutathione because they lacked one of these amino acids called cysteine. In this study we added extra cysteine to the diet of one group of malnourished children during their treatment and found that they made more glutathione and their tissues recovered faster. These results suggest that malnourished children can recover faster if they are given extra cysteine during the early phase of treatment.
Technical Abstract: BACKGROUND: Children with severe edematous malnutrition have higher than normal oxidant damage and lower concentrations of the antioxidant reduced glutathione (GSH), which are associated with slower synthesis of GSH and with low extra- and intracellular concentrations of the precursor amino acid cysteine. OBJECTIVE: We tested whether early dietary supplementation with cysteine could restore a normal GSH concentration and synthesis rate in these children. DESIGN: Erythrocyte cysteine and GSH concentrations and the fractional and absolute synthesis rates of GSH were measured in 2 groups of 16 edematous malnourished children, 10 boys and 6 girls aged 6-18 mo, at 3 times after hospital admission: at approximately 2 d (period 1), when they were malnourished and infected; at approximately 11 d (period 2), when they were malnourished but cleared of infection; and at approximately 50 d (period 3), when they had recovered. Supplementation with either 0.5 mmol. kg(-1). d(-1) N-acetylcysteine (NAC group) or alanine (control group) started immediately after period 1 and continued until recovery. RESULTS: From period 1 to period 2 the concentration and the absolute synthesis rate of GSH increased significantly (P < 0.05) in the NAC group but not in the control group. The increases in the GSH concentration and synthesis rate were approximately 150% and 510% greater, respectively, in the NAC group than in the control group. The increases in the NAC group were associated with a significant effect of supplement (P < 0.03) on erythrocyte cysteine concentration. CONCLUSION: These results suggest that the GSH synthesis rate and concentration can be restored during the early phase of treatment if patients are supplemented with cysteine.