Evaluation of glycine as a monotherapy and in combination with neomycin in promoting wound healing in rabbits

Authors

DOI:

https://doi.org/10.30539/1pfjs828

Keywords:

Glycine‎, neomycin‎, wound healing‎, Staphylococcus aureus, combination

Abstract

Background: Skin wounds infected with Staphylococcus aureus pose a significant challenge in veterinary medicine due to their delay in healing and impairment of tissue repair. Therefore, this study aims to evaluate the therapeutic effect of neomycin and glycine, both individually and in combination, on accelerating the healing of infected skin wounds experimentally. Methodology: The study included two parts: in vitro and in vivo. In the in vitro part, the minimum inhibitory concentration (MIC) for both neomycin and glycine were determined, and a checkerboard test was performed to evaluate the interaction between them. In the animal study, twenty adult rabbits were randomly divided into four groups, five rabbits for each: a positive control group (untreated), a neomycin ointment group (5% in white petrolatum), a glycine ointment group (2.5% in white petrolatum), and a combination group treated with neomycin (2.5%) + glycine (2%) formulated in a white petrolatum base. Surgical wounds measuring 2 cm² were created on the backs of the rabbits, and then all of them were injected with a bacterial suspension containing S. aureus. The wound area was assessed using photographs and analyzed using ImageJ software on the days 7, 14, and 21 after treatment. Results: Neomycin exhibited a higher inhibitory activity against S. aureus than glycine. The interaction test between the two compounds also showed a fractional inhibitory concentration index (FICI) value of 2, indicating neither a synergistic nor an antagonistic interaction (no interaction). In contrast, animal results showed that all treatment groups had a significant reduction in wound area compared to the control group, with the combination group (neomycin + glycine) achieving the fastest healing rates during the observation period. Conclusions: The combination of neomycin and glycine improves wound healing in vivo, although no synergistic interaction between the two compounds was found in the in vitro study. This suggests that the positive effect in animals may be related to local physiological mechanisms related to the inflammatory response and accelerated tissue regeneration.

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Author Biographies

  • Zainab Bashar, University of Baghdad/ College of Veterinary Medicine

    M.Sc. student, Department of Physiology, biochemistry and pharmacology , College of Veterinary Medicine, University of Baghdad, Iraq. Her research focuses on wound healing and antibacterial activity of combined therapies.

  • Dr. Ahmad Najim , University of Baghdad/ College of Veterinary Medicine

    Professor, Department of Physiology, biochemistry and Pharmacology , College of Veterinary Medicine, University of Baghdad, Iraq. His research focuses on antimicrobial resistance and experimental wound healing.

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Published

2025-12-28

How to Cite

Evaluation of glycine as a monotherapy and in combination with neomycin in promoting wound healing in rabbits. (2025). Experimental and Applied Veterinary Research Journal, 1(1), 89-97. https://doi.org/10.30539/1pfjs828