Figure 4.

HIF-1α siRNA silencing prevents NO-induced angiogenesis and expression of glycolysis-related genes in astrocytes under mild hypoxia. Primary astrocytes were transfected with HIF-1α siRNA or negative control siRNA (NC) 24 h before DETA treatment, and the transfection efficiency was confirmed by qRT-PCR (A) and Western blotting (B). mRNA expression of VEGF (C) and LDHA (D) was performed in astrocytes by qRT-PCR after 12-h exposure to 5% O₂ in the presence or absence of 1.0 mM DETA treatment. The mRNA expression of target genes was normalized to that of β-actin by using the 2^-ΔΔCT method. Western blotting was used to detect VEGF protein expression (E), and colorimetric measurement was done to for the detection of lactate (F) in the medium after 12 or 24-h exposure to 5% O₂ in the presence or absence of 1.0 mM DETA treatment. Data are expressed as mean ± S.E.M. of triplicate samples from one experiment. The experiment was repeated three times on different cell preparations. *P<0.05, **P<0.01, ***P<0.001 vs. the indicated group.