Stat3 phosphorylation induced by LPS is partially inhibited by EPO but not by hypoxia. (A,C) Liver nuclear extracts from mice treated with saline (CTL), EPO, hypoxia, LPS, and mice with combined treatments (EPO + LPS and hypoxia + LPS) were analyzed by Western blotting with an antibody to phosphorylated Stat3 and total Stat3. Blots were stripped and reprobed with an antibody to β-actin as loading control. A representative Western blot is shown. Lane “+” is a positive control consisting of total cell extracts from serum-starved HeLa cells prepared with interferon-α treatment. (B,D) Quantification of chemiluminescence to calculate the ratio of phosphorylated Stat3 relative to β-actin (pStat3/β-actin). This experiment was repeated twice, and the combined results are shown as means plus or minus SD with n = 7. Statistical analysis was performed by 1-way ANOVA; *P < .01, **P < .001; and ***P < .0001 for comparison with control mice. n.s. indicates not significant.