Figure 5
From: Hypoxia-mediated impaired erythrocyte Lands’ Cycle is pathogenic for sickle cell disease
Lysophosphatidylcholine directly promotes hypoxia-induced sickling in cultured primary SCD mouse erythrocytes and hypoxia preferentially induces PLA2 but not LPCAT via MEK/ERK signaling.
(a) Representative blood smears following treatment of blood from SCD Tg mice with Methanol (vehicle) or different concentration of LysoPC (2.5 μM, 5 μM and 10 μM as indicated) under 4% oxygen condition for 2 hours. Scale bar, 20 μm. (b) Quantification of (a). Data were represented as the mean percentage of sickle cells ± SEM. n = 3. *P < 0.05 and **P < 0.01 versus cultured SCD erythrocytes treated with DMSO or methanol. (c,d) PLA2 activity (c) and LPCAT activity (d) were measured in the cultured SCD mouse erythrocytes following 2 hours under normal air or 4% oxygen conditions. Error bars, SEM; n = 6 per group. *P < 0.05 versus SCD mouse erythrocytes under normoxic condition. (e) PLA2 activity was measured in primary cultured SCD mouse erythrocytes treated with DMSO, PKC inhibitor Go6976 (1 μM), MEK inhibitors PD98059 (20 μM) and U0126 (10 μM), PKA inhibitor H-89 (10 μM) and AMPK inhibitor compound C (10 μM) under 4% oxygen condition for 2 hours. PLA2 activity in SCD erythrocytes treated with DMSO under normoxic condition was used as a basal control. Error bars, SEM; n = 5 per group. (f) Quantification of blood smear analysis of cultured SCD mouse erythrocytes treated with DMSO or two different MEK inhibitors. Data are represented as the mean percentages of sickle cells ± SEM (n = 5). *P < 0.05 versus SCD mouse erythrocytes treated with DMSO under normoxia. **P < 0.05 relative to DMSO-treated group under hypoxia condition.
