Investigation of therapeutic effectiveness of rosmarinic acid in experimental chronic otitis media model in rats induced with pseudomonas aeruginosa

In our study, we aimed to investigate the histopathological therapeutic efficacy of rosmarinic acid (RA), which has been shown to have anti-inflammatory, antibacterial and antioxidant effects, on chronic otitis media (COM) when used in topical drop form. Materials and Methods: Thirty Wistar rats were used in the study. The rats were randomly divided into 5 groups for 6 rats. Group 1 was separated as a healthy control group. COM was induced with Pseudomonas aeruginosa (P. aeruginosa) in 4 groups. Group 2 COM follow-up group, group 3 treated with ciprofloxacin drops, group 4 treated with ciprofloxacin+RA drops, and group 5 treated with RA drops. After 14 days of follow-up, 30 rats (60 ears) were sacrificed and their temporal bones examined histopathologically for neutrophil activity, chronicity, presence of histiocytes, keratin accumulation, subepithelial edema, congestion, fibroblast proliferation, neovascularization and tympanic membrane (TM) thickness. Results: There was a significant difference between the groups in terms of neutrophil activity (p: 0.002). Neutrophil activity in group 2 was found to be significantly higher than in groups 1, 4 and 5 (respectively; p<0.001/ p: 0.01/ p: 0.02). There was a significant difference between the groups in terms of chronicity (p<0.001). The chronicity rate in group 2 was found to be significantly increased compared to group 1 (p: 0.02). There was a significant difference between the groups in terms of histocyte scores (p<0.001). The presence of histiocytes in group 2 was observed to be significantly higher than in groups 1, 3, 4 and 5 (respectively; p<0.001/ p: 0.01/ p<0.001/ p:0.001). There was a significant difference between the groups in terms of keratin accumulation (p: 0.004). Keratin debris accumulation was found to be significantly higher in group 2 than in groups 1, 4 and 5 (respectively; p:0.01/ p:0.01/ p:0.01). A significant difference was observed between the groups in terms of subepithelial edema (p: 0.004). Subepithelial edema was found to be significantly less in group 1 than in groups 3, 4 and 5 (respectively; p: 0.03/ p: 0.009/ p: 0.003). 3 A significant difference was observed between the groups in terms of congestion (p<0.001). Congestion was observed to be significantly less in group 1 than in groups 2, 3 and 4 (respectively; p<0.001/ p: 0.031/ p:0.031). A significant difference was observed between the groups in terms of fibroblast proliferation (p<0.001). Fibroblast proliferation was significantly lower in group 1 compared to groups 3 and 4 (p<0.001/ p: 0.012, respectively). Fibroblast proliferation was lower in group 2 compared to group 3 (p:0.005). A significant difference was observed between the groups in terms of neovascularization (p<0.001). Neovascularization was significantly lower in group 1 compared to groups 2 and 5 (p<0.001/ p: 0.001, respectively). A significant difference was observed between the groups in terms of TM thickness (p<0.001). TM thickness was significantly lower in group 1 compared to group 3 (p<0.001). Conclusion: Clinical and histopathological findings were obtained indicating that the use of RA healing in COM. Key Words: Chronic otitis media, rosmarinic acid, animal experiment, experimental otitis model, otitis media.