Search

Aim Alpha-thalassaemia is known to reduce intra-erythrocyte Hb S (sickle haemoglobin) concentration in sickle cell trait ( SCT) subjects. Because Hb S was shown to increase oxidative stress, the purpose of this study was to assess the effects of the coexistence of α-thalassaemia and SCT on oxidative stress markers and nitric oxide ( NO) metabolism after an acute physical exercise. Methods Forty subjects (age: 23.5 ± 2.21 years), SCT carriers ( Hb AS) or healthy subjects ( Hb AA), with (-α T) or without (- Nα T) an associated α-thalassaemia took part in the study. Plasma markers of oxidative stress [advanced oxidation protein products ( AOPP), protein carbonyl, malondialdehyde ( MDA) and nitrotyrosine], anti-oxidant defences and NO metabolism ( NOx) were measured at rest ( Trest), immediately following an incremental maximal exercise test ( Tex) and during recovery ( T1h, T2h and T24h). Results Malondialdehyde expressed as the percentage of changes from baseline was significantly higher in the Hb AS- Nα T compared with Hb AS-α T during recovery (+36.3 ± 14.1% vs. −1.8 ± 13.2% at T1h, P = 0.02; +36.6 ± 13.4% vs. −11.4 ± 12.5% at T2h, P = 0.004 and +24.1 ± 12.3% vs. −14.4 ± 11.5% at T24h, P = 0.02 in Hb AS- Nα T vs. Hb AS-α T). Compared with Hb AS- Nα T, Hb AS-α T had a higher NOx change from baseline at Tex (−23.4 ± 20.6% vs. +57.7 ± 19.3%, respectively; P = 0.005) and lower nitrotyrosine change from baseline at T1h (+7.2 ± 22.2% vs. +93.5%±29.3%, respectively; P = 0.04). Conclusion All these data suggest that the presence of α-thalassaemia may blunt the higher level of oxidative stress and the impaired bioavailability of NO observed in the SCT carriers. [ABSTRACT FROM AUTHOR]

• The AlaxoLito Plus Nasal Stent does not increase exercise performance or oxygen uptake. • RBC deformability changes depending on breathing mode and intensity. • Exhaled NO increases with stent applications compared to oral/nasal breathing. • Blood NO concentrations are not affected. To investigate the influence of the intranasal AlaxoLito Plus Nasal Stent during exercise on nitric oxide (NO) synthesis, NO exhalation, red blood cell (RBC) deformability and oxygen uptake. Parameters were measured before and after acute cycle ergometer test at different intensities. Spirometric, microrheological and NO parameters were determined for oral (OB), nasal (NB) and nasal-stent breathing (SB). RBC deformability was measured and elongation indices for 3.87 Pa and maximal deformability were calculated. RBC/plasma/exhaled NO, oxygen uptake and respiratory rate were determined. Exhaled NO was higher at rest during OB compared to SB and NB and decreased after exercise with NB and SB. Plasma and RBC NO remained unaltered during intervention. RBC deformability increased at moderate intensity during SB. Deformability decreased at moderate and medium intensity with NB. Respiratory rate for same oxygen uptake did not differ between breathing settings. The AlaxoLito Plus Nasal Stent may modulate deformability during moderate exercise and increase NO exhalation without major effects on oxygen uptake and performance. [ABSTRACT FROM AUTHOR]