Role of l-glutamine and glycine supplementation on irradiated colonic wall
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Background and aims
Radiotherapy is frequently used for cancer treatment, but it may be associated with several complications. Thus, this study aimed to evaluate the role of l-glutamine and/or glycine supplementation on the colonic wall in rats submitted to abdominal radiation.
Materials and methods
Sixty adult Wistar rats were randomly divided into six groups: I—healthy, II (control)—irradiated rats without amino acid supplementation, III—irradiated rats with glycine supplementation, IV—irradiated rats with l-glutamine supplementation, V—irradiated rats with glycine supplementation 7 days before irradiation and with l-glutamine supplementation 7 days after irradiation, and VI—irradiated rats with l-glutamine supplementation 7 days before irradiation and with glycine supplementation 7 days after irradiation. Abdominal irradiation was employed with a dose of 1,000 cGy on the eighth day of the experiment. All animals underwent laparotomy on the 15th day for resection of a colonic segment for stereologic analysis. Parametric and nonparametric tests were used for statistical analysis, with the level of significance set at p ≤ 0.05.
Control animals (group II) presented a significantly smaller total volume of colonic wall when compared to animals of groups I, III, IV, V, and VI. There was a significant increase in mucosal layer volume in the animals of group IV compared to animals of groups I, II, and III.
Our findings suggest that l-glutamine and/or glycine supplementation is beneficial for the repair of the colonic wall of rats, but l-glutamine, with its trophic effects on the colonic mucosa, seems to exhibit better results.
KeywordsGlutamine Glycine Radiotherapy Colitis Nutrition
The authors wish to thank Dr. Rafael Daher and Dr. Afrâneo Akreman, University Center of Cancer Control—Pedro Ernesto University Hospital—Rio de Janeiro State University, for their support with the irradiation procedure, and Prof. Waldemar Silva Costa, Anatomy Department—Biology Institute Roberto Alcântara Gomes—Rio de Janeiro State University, for his support with stereological analysis. This work was partially supported by a grant from Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ), Brazil.
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