Melatonin Prevents Osteoarthritis-Induced Cartilage Degradation via Targeting MicroRNA-140

Figure 4

Intra-articular injection of melatonin prevented the progression of surgically induced OA in mice. DMM surgery was performed to induce OA, and after surgery, the sham-op and DMM-op mice were injected with equal amounts of melatonin or saline twice a week for four weeks. (a) Representative images of histological and immunohistochemical staining of the medial femoral condyle in OA mice. Sagittal sections of cartilage were stained by hematoxylin and eosin (H&E) and Safranin O (S.O.)/Fast Green. Immunohistochemical analyses were conducted to target COL II and COL I. . (b) OARSI scores were calculated based on the Safranin O/Fast Green staining results. (c, d) The percentages of COL II-positive (c) or COL I-positive (d) chondrocytes were counted. In each section, the quantitative analyses were counted at three random regions and then averaged. Values are the of ten independent experiments (). Statistically significant differences are indicated by ## where vs. the CTRL group and where between the indicated groups.

(a)

(b)

(c)

(d)