Fig. 1

Prok2 is a target of HIF-2α in chondrocytes and exhibits upregulation in OA cartilage of mice and humans. A Primary-culture mouse chondrocytes were treated with vehicle alone or IL-1β (1 ng/ml, 36 h). Alternatively, chondrocytes were infected with 800 MOI of Ad-C (control), Ad-HIF-2α, or Ad-ZIP8 for 36 h. Presented is a heatmap of microarray analysis data for prokineticins (Prok) and their receptors (ProkR, n=3). B, C RT-PCR (B) and qRT-PCR (C) analysis of the indicated molecules in chondrocytes infected with 800 MOI of Ad-C (control) or the indicated MOI of Ad-HIF-2α for 36 h (n=7). D Positioning of HRE sequences in Prok2 promoter. E Representative immunostaining images of Prok2 in cartilage from sham- or DMM-operated mice and semi-quantification of Prok2 positive pixels (n=6 mice per group). F Immunostaining images and semi-quantification of Prok2 positive pixels in damaged and undamaged human OA cartilage (n=5 patients). Values are presented as mean ± 95% CI, and significance was evaluated by paired t-test. Scale bar: 50 μm