Journal: Journal of Orthopaedic Translation
Article Title: Intermittent intra-articular delivery of FGF8b enhances cartilage homeostasis and attenuates osteoarthritis progression
doi: 10.1016/j.jot.2025.101037
Figure Lengend Snippet: FGF8b exerts a chondroprotective effect via the FGFR3-PI3K-AKT signaling pathway. A. Surface plasmon resonance analysis shows the high-affinity binding of FGF8b to FGFR3. B-C. FGF8b treatment of SW1353 chondrocytes for 15 min increased the expression of phosphorylated FGFR3. D-E. The knockdown efficiency of FGFR3 following transfection with FGFR3 siRNA in SW1353 cells was assessed by Western blotting. F-H. The chondroprotective effect of FGF8b for 24 h was partially attenuated after FGFR3 knockdown. I. KEGG enrichment analysis of transcriptome sequencing data suggested an upregulation of the PI3K-AKT signaling pathway following FGF8b treatment for osteoarthritis. J-L. The FGFR3-PI3K-AKT signaling pathway was downregulated in chondrocytes treated with IL-1β for 15 min, whereas FGF8b treatment activated the FGFR3-PI3K-AKT signaling pathway. M. The activation of the PI3K-AKT signaling pathway by FGF8b is dependent on FGFR3. N-P. The chondroprotective effect of FGF8b was partially abolished upon blockade of the PI3K-AKT signaling pathway using the LY294002 inhibitor under inflammatory conditions. n = 3, ns: not significant, ∗P < 0.05, ∗∗P < 0.01, ∗∗∗P < 0.001 and ∗∗∗∗P < 0.0001.
Article Snippet: The primary antibodies used were as follows: FGF8b (1:100, AF-423-NA, R&D Systems), Sox9 (1:200, Ab185230 , Abcam), Acan (1:200, AB1031, Invitrogen), Col X (1:200, Ab58632, Abcam) and Mmp13 (1:200, 18165-1-AP, Proteintech).
Techniques: SPR Assay, Binding Assay, Expressing, Knockdown, Transfection, Western Blot, Sequencing, Activation Assay