Fig 2: Result of protein docking analysis between 21 active compounds and 11 main proteins. (A) Representation of docking energy. Represented 3D molecular docking between four active compounds which were reported to OA in previous studies with (B) MMP13, (C) SOX9, (D) COL2A1, and (E) COL10A1.

Fig 3: Representation of the relative mRNA (A) and protein expression (B) of epithelial phenotypic markers (E-cadherin, CK19); MSC phenotypic markers (Zeb1, Snail1) (C,D); and osteochondral markers (Col2A1, OPN, Sox9, Runx2) (E,F); in PRECs compared with NRK cells, * p < 0.05 (n = 3).

Fig 4: Effects of osteogenic (Os) induction and osteo-chondrogenic (Os-Chon) induction on osteochondrogenic differentiation of three-dimensional-induced pluripotent stem cells (3D-iPSC) constructs. Expression of (A) osteogenic marker genes [osterix (Osx), collagen 1a1 (Col1a1) and osteocalcin (Ocn)] and (B) chondrogenic marker genes [Sox9, collagen 2a1 (Col2a1) and aggrecan] were evaluated using real-time reverse transcription polymerase chain reaction (RT-PCR) on day 2 (the day when the induction commenced), on days 5, 12, and 22 (Os induction; same induction protocol as Os-Chon induction during this period) and on days 36 and 43 (Os or Os-Chon induction). The data represent the mean ± SD (n = 3). Different letters indicate significant differences between groups (p < 0.05, one-way analysis of variance (ANOVA) with Tukey’s multiple comparison test). (C) Expression of pluripotency marker genes, Nanog and Oct3/4, was evaluated by semi-quantitative RT-PCR analysis. GAPDH expression was used as an internal control.

Fig 5: Reduced miR-9 and increased MMP-13 expression levels in cartilage samples from OA patients. Reverse transcription-quantitative polymerase chain reaction for (A) miR-9 expression levels and (B) MMP-13 mRNA expression levels. (C) Western blot analysis of protein expression levels. *P<0.05 vs. control group. miR, microRNA; MMP, matrix metalloproteinase; OA, osteoarthritis; COL2A1, collagen type II a1 chain.