Histopathological Effects of Pseudomonas aeruginosa Exotoxin A on Diabetic Skin Wounds in Rats
DOI:
https://doi.org/10.56714/bjrs.52.1.12Keywords:
Pseudomonas aeruginosa, exotoxin A, diabetic wounds, wound healing, BiofilmAbstract
Diabetes definitely affects the wound healing process by interfering with tissue remodeling and prolonging the inflammatory phase. This study aims to evaluate the histopathological effects of Exotoxin A (ETA), one of the main virulence factors of Pseudomonas aeruginosa bacteria, on the healing of skin wounds in diabetic rats. Techniques: Full-thickness skin wounds were created in rats with diabetes induced by alloxan. Rats were divided into three groups: a control group treated with phosphate-buffered saline (PBS) and two groups receiving Exotoxin A (ETA) at doses of 10 µg and 50 µg. Tissue samples were collected on days 4, 8, 12, and 16, and histological changes were evaluated using hematoxylin and eosin (H&E) staining. The diabetes control wounds showed prolonged inflammatory exudation, aberrant collagen organization, and a significant delay in epidermal reconstitution. Conversely, wounds treated with ETA showed poor regeneration and early cellular damage. Both doses (10 µg and 50 µg) demonstrated significant improvement in the later stages compared to the control, including thicker epidermis, more pronounced granulation tissue development, better collagen fiber organization, and nearly complete wound closure on days 12 and 16.Overall, Exotoxin A causes early damage to diabetic wounds but later promotes better tissue reconstruction. These results suggest that ETA may have a regulatory role in the healing of chronic wounds, necessitating further investigation to identify the precise mechanisms and evaluate the efficacy of therapy
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