Protective Effect of Zataria Multiflora Boiss in Selenite-Induced Cataracts: Histopathological and Morphological...

Cataracts are a leading cause of visual impairment worldwide, necessitating effective non-surgical preventative strategies. This study is the first to evaluate the morphological and histopathological effects of Zataria multiflora Boiss essential oil (ZE) on selenite-induced cataracts in rats.

Seventy-two male Sprague-Dawley rat pups were randomly assigned to six groups: control (C), vehicle control (VC), ZE control (ZC), selenite (S), selenite plus vehicle (SV), and selenite plus ZE (SE). Cataracts were induced by a single subcutaneous injection of sodium selenite (30 μmol/kg) on postnatal day 8. ZE (500 μL/kg, diluted 1:1 with olive oil) was administered orally twice weekly for 5 weeks. Cataract severity was graded weekly by using Hiraoka's scale (0-6) by a blinded ophthalmologist. Histopathological changes were qualitatively assessed via hematoxylin and eosin staining. Statistical analysis employed the Kruskal-Wallis test with Dunn's post-hoc test.

No cataracts developed in the control groups (mean grade: 0). The S and SV groups developed severe cataracts (mean grade: 5.14 ± 0.64). ZE treatment significantly reduced cataract severity in the SE group (mean grade: 2.07 ± 0.59; P < 0.05 vs. S and SV). Histopathology showed that ZE preserved lens architecture and markedly reduced degenerative changes compared with S and SV.

This study provides the first morphological and histological evidence that ZE can prevent or delay cataract formation by preserving lens structure and function in a selenite-induced rat model. ZE demonstrates promising potential as a natural therapeutic agent for cataract prevention.