Antioxidant activity of Lavandula x intermedia and its healing effect against UVB-induced corneal damage in rats.

Long-term exposure to ultraviolet (UV) radiation causes corneal damage. Medicinal plants with antioxidant and anti-inflammatory effects may be protective against corneal damage. This study was conducted to investigate the antioxidant activity, therapeutic potential in corneal damage and phytochemical content of Lavandula x intermedia. The antioxidant activity of the extract was evaluated by metal chelation capacity, antioxidant capacity, reducing power, ABTS and DPPH scavenging effect tests. The chemical composition of the extract was analyzed by LC-MS/MS. The effect of the extract on rats was investigated by macroscopic, immunohistochemical, histopathological and genetic studies. The extract was found to have strong DPPH scavenging effect, moderate ABTS scavenging effect and metal chelation capacity. LC-MS/MS results revealed that cynaroside, cosmosiin and rosmarinic acid were the most abundant in the extract. Histopathological findings revealed a significant reduction in both corneal defect and inflammation in the extract group. According to the immunohistochemical analysis results, the decrease in IL-1β and Cox-1 expression in the extract group was found to be significant compared to the damage group. SIRT1 values were significant in the extract group compared to the vehicle and control groups (p < 0.05). In conclusion, this study revealed that L. x intermedia extract accelerated corneal healing against UVB-induced corneal damage.