Kindlin-2 Promotes Chondrogenesis and Ameliorates IL-1beta-Induced Inflammation in Chondrocytes Cocultured with BMSCs in the Direct Contact Coculture System

Figure 5

Kindlin-2-mediated PI3K/AKT pathway protects chondrocytes against IL­1beta-induced inflammation. (a, b) Knockdown of Kindlin-2 or inhibition of PI3K/AKT/mTOR signaling in chondrocytes increased IL-1beta-induced chondrocyte apoptosis, as detected by Annexin V-FITC/PI staining and flow cytometry. Quantitative evaluation of Annexin V-FITC/PI staining results was performed. Values are expressed as , , ns indicates no significance. (c, d) Inhibition of PI3K/AKT/mTOR signaling in Kindlin-2 OE chondrocytes in the direct contact coculture system increased IL-1beta-induced chondrocyte apoptosis, as detected by Annexin V-FITC/PI staining and flow cytometry. Quantitative evaluation of Annexin V-FITC/PI staining results was performed. Values are expressed as , . (e, f) Knockdown of Kindlin-2 or inhibition of PI3K/AKT/mTOR signaling in chondrocytes further reduced mitochondrial membrane potential induced by IL-1beta, as detected by JC-1 dye and flow cytometry. Quantitative evaluation of the percentage of collapsed mitochondrial membrane potential is expressed as , , ns indicates no significance. (g, h) Inhibition of PI3K/AKT/mTOR signaling in Kindlin-2 OE chondrocytes in the direct contact coculture system reduced the mitochondrial membrane potential induced by IL-1beta, as detected by JC-1 dye and flow cytometry. Quantitative evaluation of the percentage of collapsed mitochondrial membrane potential is expressed as , . (i) Knockdown of Kindlin-2 or inhibition of PI3K/AKT/mTOR signaling in chondrocytes increased ROS levels induced by IL-1beta, as determined by DCHDA assay. Values are expressed as , , ns indicates no significance. (j) Inhibition of PI3K/AKT/mTOR signaling in Kindlin-2 OE chondrocytes in the direct contact coculture system increased ROS levels induced by IL-1beta, as determined by DCHDA assay. Values are expressed as , .

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

(i)

(j)