Pfn1 regulates metabolism of HSCs. (A) Measurement of ATP content, oxygen consumption, and labeled glycolytic flux per ATP in G0 and G1 fractions of LT-HSCs (as Lin⁻Sca-1⁺Kit⁺Flk2⁻CD34⁻ cells) (n = 3-6; *P < .05). (B) Hif-1a expression in control and Sclpfn1 HSCs at days 1 and 3 after tamoxifen treatment (n = 3; *P < .05). (C-D) Metabolic profiles (ATP content, oxygen consumption, and glycolytic flux per ATP) in control and Sclpfn1 HSCs at (C) day 2 or (D) day 8 after tamoxifen treatment. Sclpfn1 HSCs are much less glycolytic (n = 3-6; *P < .05). (E) Mitochondrial super-oxide (MitoSOX) was analyzed in G0 and G1 cells from control and Sclpfn1 LT-HSCs (n = 3). (F-I) Control and Sclpfn1 mice were treated with tamoxifen for 7 days followed by NAC treatment of another 8 days. (F) Levels of ROS were determined by analysis for carboxy-DCFDA, and percentage of DCFDA⁺ LT-HSCs are shown (n = 4-6; */**/***P < .05). (J) Cell cycle status, (H) frequency, and (I) levels of apoptosis of HSCs were analyzed (n = 3; *P < .05).