Patchouli Alcohol Inhibits D-Gal Induced Oxidative Stress and Ameliorates the Quality of Aging Cartilage via Activating the Nrf2/HO-1 Pathway in Mice

Figure 1

Influences of patchouli alcohol (PA) on cartilage quality in D-gal-induced aging mice. (a) Effect of PA on ECM degradation marker gene expression of collagen 2a1 (COL2A1), aggrecan (ACAN), and matrix metalloproteinase 13 (MMP13) in D-gal-caused senescent chondrocytes was analyzed by RT-qPCR. (b) The quantitative real-time PCR (qRT-PCR) results of the mRNA expression of Tp53, Cyclin-Dependent Kinase Inhibitor 1A (Cdkn1a/p21^Cip1/Waf1), and Cyclin-Dependent Kinase Inhibitor 2A (Cdkn2a/p16^INK4a). (c) Representative alcian blue and safranin O-fast green (SO) staining images in NOR group, D-gal group, and D-gal and PA (20 mg/kg) group. Scale bar, 250 μm; scale bar (enlarged), 100 μm. (d) Immunochemical staining of articular cartilage with COL2A1 and MMP13 in the NOR group, D-gal group, and D-gal and PA (20 mg/kg) group (staining positive areas were circled in red). Scale bar, 100 μm. (e) The diagram was applied to display modified Mankin’s score of articular cartilage. (f) Quantitative analysis of COL2A1 and MMP13 immunostaining (positive cells %). Scale bar: 50 μm. . vs. NOR group; ^# vs. D-gal group.