Fig. 3

1,25(OH)₂D₃ mediates HIF-1α expression via NF-κB pathway. a and b Western blot analyses (a) of HOKs challenged with LPS or saline in the presence or absence of BAY 11–7082 (20 nM), and densitometric analysis (b). c and d Western blot analyses (c) of HOKs transfected with IKKβ plasmids or empty vector in the presence or absence of 1,25(OH)₂D₃, and densitometric analysis (d). e A predicted κB binding site (red) in human HIF-1α gene promoter. The initiation codon was labeled in bold font. f NF-κB binding site harbored in HIF-1α gene promoter was located between − 125 and − 136. g ChIP assays of HOKs treated by LPS or saline in the presence or absence of 1,25(OH)₂D₃. *P < 0.05, **P < 0.01, ***P < 0.001 vs. corresponding controls; #P < 0.05, ##P < 0.01 vs. LPS or Ikkβ; Ctrl, control; 1,25VD, 1,25(OH)2D3. All assays were conducted for three times, n = 3