Investigation of the effects of aged garlic extract and S- allylcysteine on endothelin-1 levels and histopathological findings in an ovalbumin-induced allergic rhinitis rat model.

Allergic rhinitis is characterised by symptoms such as sneezing, nasal itching, and rhinorrhea. Endothelin-1 (ET-1) is a potent vasoactive peptide that has also been implicated in airway inflammation. The aim of this study was to investigate the effects of aged garlic extract (AGE) and S-allylcysteine (SAC) on ET-1 levels and histopathological findings in an ovalbumin (OVA)-induced allergic rhinitis rat model. Allergic rhinitis was induced using OVA and alum adjuvant. AGE (250 mg/kg) and SAC (6.5 mg/kg) were administered orally by gavage. Serum ET-1 levels were measured at the end of the experiment. ET-1 levels were higher in the OVA group compared to the control group and were reduced in both the AGE- and SAC-treated groups. The differences between groups were statistically significant (p < 0.05). Histopathological examination of lung tissues revealed mild peribronchial fibrotic changes in the OVA and SAC groups, while nasal epithelial morphology did not show marked differences among the groups. These findings suggest that AGE and SAC may be associated with reduced ET-1 levels in this experimental model.