2024-11-0920191386-029110.3233/CH-1905632-s2.0-85078512882http://dx.doi.org/10.3233/CH-190563https://hdl.handle.net/20.500.14288/14650Background: Erythrocyte deformability is impaired in sickle cell disease (SCD). The regulation of cytoskeletal protein organization plays a key role in erythrocyte deformability. The activation of adenylyl cyclase (AC)/cAMP/Protein kinase A (PKA) signaling pathway was associated with increased deformability in healthy erythrocytes, however the role of this pathway in SCD is unknown. Objective: We evaluated mechanical responses of sickle red blood cells under physiological levels of shear stress and the possible link between their deformability and AC/cAMP/PKA signaling pathway. Methods: The shearing of sickle red blood cells at physiological level (5 Pa) and the measurement of deformability were performed by a laser assisted optical rotational cell analyzer (LORRCA). Results: Red blood cell deformability increased of 2.5-6.5% by blocking the activity of phosphodiesterase with Pentoxifylline (10 mu M) (p < 0.05). The inhibition of AC with SQ22536 (100 mu M) produced more significant rise in deformability (+4.8-12%, p < 0.01). No significant change was observed by the inhibition of PKA with H89 (10 mu M). Conclusion: Pentoxifylline and SQ22536 increased the deformability of sickle red blood cells under fluid shear stress. Modulation of the AC/cAMP/PKA pathway could have the potential to be an effective therapeutic approach for SCD through shear-induced improvements of RBC deformability.HematologyPeripheral vascular diseasesJournal Article1875-8622509413300004Q38764