Efficacy of Mitochondrial Antioxidant Plastoquinonyl-decyl-triphenylphosphonium Bromide (SkQ1) in the Rat Model of Autoimmune Arthritis

Figure 4

Microscopy of typical pathological lesions of paw joints of treated and untreated rats with experimental rheumatoid arthritis in experiment II. Animals were sacrificed 30 days after arthritis induction. H&E staining, 100x. (a) Normal paw joint, scores: inflammatory infiltration: 0, synovial hyperplasia: 0, cartilage destruction: 0, and bone destruction: 0; (b) untreated control: inflammatory infiltration: 3 (severe inflammatory infiltration), synovial hyperplasia: 3 (massive synovial cells proliferation and in some cases also severe destruction of synovial membrane), cartilage destruction: 2 (necrosis of cartilages), and bone destruction: 3 (numerous resorption lacunae); (c) dexamethasone: inflammatory infiltration: 0, synovial hyperplasia: 0, cartilage destruction: 0, and bone destruction: 0; (d) 50 nmol/kg/day SkQ1: inflammatory infiltration: 3, synovial hyperplasia: 3, cartilage destruction: 3 (destruction of cartilages with formation of pannus), and bone destruction: 3; (e) 250 nmol/kg/day SkQ1: inflammatory infiltration: 2 (moderate inflammatory infiltration), synovial hyperplasia: 2 (foci with more than two layers of cells in synovial membrane), cartilage destruction: 0, and bone destruction: 0; (f) 1250 nmol/kg/day SkQ1: inflammatory infiltration: 1 (mild inflammatory infiltration), synovial hyperplasia: 1 (foci with more than one layer of cells in synovial membrane), cartilage destruction: 1 (erosive surface of cartilages), and bone destruction: 1 (rare resorption lacunae). Inflammatory infiltration in joint tissues and exudation in articular cavity (black asterisks), foci of cartilage destruction (white arrows), bone resorption lacunae (black arrows), and necrotic or hyperplastic synovia (white asterisks).