Fig. 4.

P-AscH⁻-induced HIF-1α suppression is due to a prolyl hydroxylase-independent increase in degradation. a Ribosomal inhibition in hypoxia with cycloheximide (CHX) and subsequent treatment with P-AscH⁻ (5 mM, 7 pmol cell^{− 1}) results in decreased HIF-1α as demonstrated by Western blot. b Densitometric analysis demonstrates decreased HIF-1α with CHX and P-AscH⁻ (*p < 0.1, n = 3, One-Way ANOVA, Dunn’s multiple comparisons test). c Proteasomal inhibition utilizing MG-132 reverses P-AscH⁻ induced (5 mM, 7 pmol cell⁻¹) suppression of HIF-1α protein as demonstrated by Western blot. d Densitometric analysis, suggesting P-AscH⁻ increases degradation of HIF-1α as opposed to inhibiting synthesis. e Representative Western blot demonstrating inhibition of prolyl hydroxylase utilizing cobalt chloride (CoCl₂) fails to reverse P-AscH⁻-induced (7 mM, 7 pmol cell⁻¹) HIF-1α protein suppression. f Densitometric analysis demonstrated that CoCl₂ does not reverse P-AscH⁻ HIF-1α suppression (*p < 0.05, n = 3)