Figure 4.

Effect of quercetin on hemolysis on RBCs from SCA patients in deoxygenated isosmotic sucrose solutions. RBCs were pre-incubated without or with quercetin in Ca²⁺-free N-MBS for 30 min. They were then incubated in isosmotic non-electrolyte solution in Eschweiler tonometers and equilibrated with N₂ for 60 min. Hemolysis (% total RBCs) was measured at 10 min intervals by removing serial aliquots of RBC suspensions, pelleting intact RBC by centrifugation, and measuring the optical density (OD) of the supernatant at 540 nm. About 100% hemolysis was ascertained by measuring OD in RBC suspensions treated with X-100 Triton (0.1% final). Histograms represent means ± SEM, n = 4. *p < 0.05, comparing RBCs in the absence (control) and presence of quercetin.