Effects of glutamine alone or in combination with zinc and vitamin A on growth, intestinal barrier function, stress and satiety-related hormones in Brazilian shantytown children.
OBJECTIVE
To determine the impact of supplemental zinc, vitamin A, and glutamine alone or in combination on growth, intestinal barrier function, stress and satiety-related hormones among Brazilian shantytown children with low median height-for-age z-scores.


METHODS
A randomized, double-blind, placebo-controlled trial was conducted in children aged two months to nine years from the urban shanty compound community of Fortaleza, Brazil. Demographic and anthropometric information was assessed. The random treatment groups available for testing (a total of 120 children) were as follows: (1) glutamine alone, n = 38; (2) glutamine plus vitamin A plus zinc, n = 37; and a placebo (zinc plus vitamin A vehicle) plus glycine (isonitrogenous to glutamine) control treatment, n = 38. Leptin, adiponectin, insulin-like growth factor (IGF-1), and plasma levels of cortisol were measured with immune-enzymatic assays; urinary lactulose/mannitol and serum amino acids were measured with high-performance liquid chromatography. ClinicalTrials.gov: NCT00133406.


RESULTS
Glutamine treatment significantly improved weight-for-height z-scores compared to the placebo-glycine control treatment. Either glutamine alone or all nutrients combined prevented disruption of the intestinal barrier function, as measured by the percentage of lactulose urinary excretion and the lactulose:mannitol absorption ratio. Plasma leptin was negatively correlated with plasma glutamine (p = 0.002) and arginine (p = 0.001) levels at baseline. After glutamine treatment, leptin was correlated with weight-for-age (WAZ) and weight-for-height z-scores (WHZ) (p≤0.002) at a 4-month follow-up. In addition, glutamine and all combined nutrients (glutamine, vitamin A, and zinc) improved the intestinal barrier function in these children.


CONCLUSIONS
Taken together, these findings reveal the benefits of glutamine alone or in combination with other gut-trophic nutrients in growing children via interactions with leptin.
Center for Global Health, Department of Physiology and Pharmacology, Clinical Research Unit & Institute of Biomedicine, School of Medicine, Federal University of Ceará, Fortaleza, CE, Brazil.
Aldo A M
AA
Lima
South Texas Veterans Hospital, San Antonio, TX, USA.
Gregory M
GM
Anstead
Center for Global Health, Division of infectious Diseases, School of Medicine, University of Virginia, Charlottesville, VA, USA.
Qiong
Q
Zhang
Center for Global Health, Department of Physiology and Pharmacology, Clinical Research Unit & Institute of Biomedicine, School of Medicine, Federal University of Ceará, Fortaleza, CE, Brazil.
Ítalo L
ÍL
Figueiredo
Center for Global Health, Department of Physiology and Pharmacology, Clinical Research Unit & Institute of Biomedicine, School of Medicine, Federal University of Ceará, Fortaleza, CE, Brazil.
Alberto M
AM
Soares
Center for Global Health, Department of Physiology and Pharmacology, Clinical Research Unit & Institute of Biomedicine, School of Medicine, Federal University of Ceará, Fortaleza, CE, Brazil.
Rosa M S
RM
Mota
Center for Global Health, Department of Physiology and Pharmacology, Clinical Research Unit & Institute of Biomedicine, School of Medicine, Federal University of Ceará, Fortaleza, CE, Brazil.
Noélia L
NL
Lima
Center for Global Health, Department of Physiology and Pharmacology, Clinical Research Unit & Institute of Biomedicine, School of Medicine, Federal University of Ceará, Fortaleza, CE, Brazil.
Richard L
RL
Guerrant
Center for Global Health, Department of Physiology and Pharmacology, Clinical Research Unit & Institute of Biomedicine, School of Medicine, Federal University of Ceará, Fortaleza, CE, Brazil.
Reinaldo B
RB
Oriá
D000293:Adolescent; D000886:Anthropometry; D001938:Brazil; D002648:Child; D002675:Child, Preschool; D019587:Dietary Supplements; D004311:Double-Blind Method; D004338:Drug Combinations; D005260:Female; D005973:Glutamine / Q000008:administration & dosage*; D048788:Growth and Development / Q000187:drug effects*; D006728:Hormones / Q000097:blood; D006801:Humans; D007223:Infant; D007334:Insulin-Like Growth Factor I / Q000032:analysis / Q000187:drug effects; D007413:Intestinal Mucosa / Q000187:drug effects*; D008297:Male; D044342:Malnutrition / Q000188:drug therapy; D011204:Poverty Areas; D013312:Stress, Physiological / Q000187:drug effects; D016896:Treatment Outcome; D014801:Vitamin A / Q000008:administration & dosage*; D014815:Vitamins / Q000008:administration & dosage*; D015032:Zinc / Q000008:administration & dosage*
D004338:Drug Combinations; D006728:Hormones; D014815:Vitamins; D005973:Glutamine; D014801:Vitamin A; D007334:Insulin-Like Growth Factor I; D015032:Zinc