Ameliorative Effect of Curcumin Nanoparticles against Monosodium Iodoacetate-Induced Knee Osteoarthritis in Rats

Figure 9

Photomicrographs of hematoxylin and eosin- (H&E-) stained sections of the left knee joints. (a) shows the normal control group with the normal architecture of the articular cartilage that consists of a noncalcified (NCC) region, which is arranged into superficial (S), transitional (T), and radial (R) zones and calcified (CC) region with a clear intact tidemark in between (scale  μm). It also shows subchondral bone (SC) with well-oriented bony trabeculae (arrow). (b)–(d) show the MIA-treated group (osteoarthritic rats), wherein (b) depicts fissures, surface fibrillation (curved arrows), chondrocytes with hyperchromatic nuclei (arrowheads), chondrocytes clusters (thin arrow), marked loss of (matrix and chondrocytes), and degenerated and disorganized bone trabeculae (thick arrows); (c) shows a decrease in articular cartilage thickness, unclear tidemark, an abnormal subchondral with an increase in trabecular thickness, and bone marrow space (BM) containing fewer hematopoietic cells; and (d) shows degeneration (asterisk) and heterogeneous distribution of chondrocytes in the growth plate. (e) and (f) show the treatment group (MIA+CUR-loaded PLGA NPs), wherein (e) displays a marked restoration of the normal structure of articular cartilage with an intact surface, except for some damaged parts () and a few hyperchromatic nuclei, an increase in cellularity, a partial improvement in tidemark integrity, and nearly normal bone marrow space (BM) relative to the MIA group (scale  μm), and (f) demonstrates neatly and properly aligned and oriented chondrocytes of the growth plate (scale  μm).

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