Fig. 6

Morphological examination of the knee joints in OA mice (HE staining). All animals were sacrificed 28 days after the last treatment. A histopathological study of the cartilage and subchondral bone in ACLT-induced OA mice was performed after GE-P (100 mg/kg/day, d), GE-P (300 mg/kg/day, e), GE-L (100 mg/kg/day, f), GE-L (300 mg/kg/day, g), and celecoxib (10 mg/kg/day, c) treatment. In the normal group (sham, a), the articular cartilage tissue (red rectangle frame) remained relatively intact, with a well-preserved smooth cartilage surface and organized chondrocytes when compared with the saline group (ACLT, b), which presented with severe and extensive destruction of the cartilage in HE stained sections. Grading of the sections by a veterinary pathologist showed significant inflammation, synovial hyperplasia, and cartilage fissures along with disoriented and scattered dead chondrocytes in the saline group (sham). The Mankin score was evaluated for the grading of OA cartilage based on its structure and cell distribution in picture h. Damaged cartilage, disorganized chondrocyte clusters, and rough cartilage surfaces were seen in the ACLT-induced OA mice model. Original magnification, × 400. ***p < 0.001, significant difference when compared with the vehicle control (Sham). ^#p < 0.05, ^##p < 0.01, ^###p < 0.001, significant differences when compared with the saline-treated (ACLT) mice