ABSTRACT Objective: Glutamine (GLN) plays an important role in the regulation of acid–base balance, protein turnover, ammonia metabolism, catabolic situations, and immune system enhancement. The prevention, treatment, and care of oral mucosal lesions are very important in terms of leading to several clinical and economic problems. The aim of the present study was to investigate the positive and different effects of GLN on traumatic oral mucosal lesions by its administration via the topical or systemic (enteral and parenteral) route. Methods: Twenty-one Wistar albino rats were included in the experimental study and divided into four groups. Traumatic oral mucosal lesions were created in all rats after the intraperitoneal administration of anesthesia. In the control group, traumatic oral mucosal lesions were created and no treatment was applied. In the study groups, GLN was applied via the parenteral, enteral, and topical routes. Healing of lesions was macroscopically observed on high-resolution photographs. Rats were sacrifced, and biopsies were obtained for histopathological and biochemical evaluations. Results: In histopathological evaluations of the biopsies, a signifcant difference was observed between the control and parenteral/topical groups for acute infammation, between the control and parenteral groups for epithelial proliferation, and between the control and topical groups for fbrosis. In biochemical evaluations, only malondialdehyde levels had a signifcant difference between the control and enteral groups (p<0.02). Conclusion: A positive effect of GLN administration was observed for the treatment of traumatic oral mucosal lesions. It was considered that GLN administration via the topical or enteral route may present an alternative on traumatic oral mucosal lesions. However, GLN administration via the parenteral route had better results than that via topical and enteral routes. Keywords: Experimental study, glutamine, oral mucositis, traumatic wounds Effects of Glutamine on Healing of Traumatic Oral Mucosal Lesions: An Experimental Study Sedat Akbaş 1 , Enes Karabulut 2 , Ayşe Pervin Sutas Bozkurt 3 , Övgü Aydın 4 , Dilek Düzgün Ergün 5 , Gürcan Güngör 3 1 Department of Anesthesiology and Reanimation, İnönü University School of Medicine, Malatya, Turkey 2 Department of Clinical Trials, Turkish Medicines and Medical Devices Agency, Ankara, Turkey 3 Department of Anesthesiology and Reanimation, İstanbul University-Cerrahpaşa, Cerrahpaşa School of Medicine, İstanbul, Turkey 4 Department of Pathology, İstanbul University-Cerrahpaşa, Cerrahpaşa School of Medicine, İstanbul, Turkey 5 Department of Biophyshics, İstanbul University-Cerrahpaşa, Cerrahpaşa School of Medicine, İstanbul, Turkey Cite this article as: Akbaş S, Karabulut E, Sutas Bozkurt AP, Aydın Ö, Düzgün Ergün D, Güngör G. Effects of Glutamine on Healing of Traumatic Oral Mucosal Lesions: An Experimental Study. JAREM 2019; 9(1): 6-13. Received Date: 27.02.2018 Accepted Date: 09.07.2018 © Copyright 2019 by University of Health Sciences Gaziosmanpaşa Taksim Training and Research Hospital. Available on-line at www.jarem.org DOI: 10.5152/jarem.2019.2008 Corresponding Author: Sedat Akbaş, E-mail: sedat.akbas@inonu.edu.tr 6 Original Investigation ORCID IDs of the authors: S.A. 0000-0003-3055-9334; E.K. 0000-0001-7871-0609; A.P.S.B. 0000-0002-2073-826X; Ö.A. 0000-0002-1773-8816; D.D.E. 0000- 0002-9656-6839; G.G. 0000-0003-2437-8246. INTRODUCTION Oral lesions are defned as the infammation of oral mucosa, com- promised by damage of the epithelial tissue with the impairment of the saliva barrier, damage of the epithelial cells, and frequent ulcerations (1). Oral mucosal cells, along with secreted substances, constitute the frst line of defense. The lesions cause opportunistic oral infections by inficting mucosal damage and fatal complica- tions, such as bacteremia, fungemia, and sepsis (1). The lesions, which lead to severe pain, are the main cause of diffculties related to chewing, swallowing, and speaking, which then contribute to dehydration, malnutrition, anorexia, and cachexia (1). The major risk factors for oral mucositis are age, sex, genetic fac- tors, lack of oral hygiene, xerostomia, nutrition status, acute or chronic dental diseases, infections, malignancies, smoking, alco- hol, presence and severity of instrumentation inside the mouth, chemotherapy and radiotherapy, and treatment-related causes (2). The treatment of oral mucositis includes options of nutritional support, pain management, oral hygiene, and palliation of xero- stomia. Requirement for total parenteral nutrition and treatment of infections, long duration of febrile neutropenia, using higher doses of opioid analgesics for oral mucositis lead to a prolonged hospitalization period, thereby increasing treatment costs. Amino acids and vitamins are used to support the immune sys- tem (3). Glutamine (GLN) has an important role in the synthesis of nucleotides in rapidly dividing cells (4). GLN, which plays a crucial role in wound healing, is not present in suffcient quantities in enteral and total parenteral nutrition because of solubility and