Fig. 4.

Effects of pentosan polysulfate (PPS) sodium and polysulfated glycosaminoglycan (PSGAG) on chondrogenesis of canine bone marrow-derived mesenchymal stem cells (cBMSC) in micromass culture maintained for 20-days. Photomicrographs represent the treatment conditions as; (A) 10% DMEM -negative control (NC), (B) chondrogenic differentiation medium (CDM) -positive control (PC), (C) 1.0 µg/ml PPS, (D) 3.0 µg/ml PPS, (E) 5.0 µg/ml PPS, (F) 1.0 µg/ml PSGAG, (G) 3.0 µg/ml PSGAG and (H) 5.0 µg/ml PSGAG. In 20-days culture, the supplementation of PPS to CDM significantly enhanced chondrogenic pelleting and PG deposition at all concentrations compared to NC, PC and PSGAG as indicated by intense and homogenous Alcian blue staining of pellets. In contrast, PSGAG inhibited chondrogenic pellet formation in a dose-dependent pattern leading to formation of fibroblastic-like pellets that stained poorly with Alcian blue, an indication of reduced PG deposition. Results are from one representative of six independent experiments (n=6). Scale bars: 20 µm.