Effects of regular physical activity on skeletal muscle structural, energetic, and microvascular properties in carriers of sickle cell trait

• Published in: Journal of applied physiology (1985) Vol. 113; no. 4; pp. 549 - 556
• Main Authors: Vincent, Lucile, Oyono-Enguéllé, Samuel, Féasson, Léonard, Banimbek, Viviane, Dohbobga, Macias, Martin, Cyril, Thiriet, Patrice, Francina, Alain, Dubouchaud, Hervé, Sanchez, Hervé, Chapot, Rachel, Denis, Christian, Geyssant, André, Messonnier, Laurent
• Format: Journal Article
• Language: English
• Published: United States American Physiological Society 15.08.2012
• Subjects: Adaptation, Physiological; Adult; Bioenergetics; Biopsy; Blood vessels; Capillaries - physiopathology; Citrate (si)-Synthase - metabolism; Electron Transport Complex I - metabolism; Electron Transport Complex IV - metabolism; Energy Metabolism; Exercise; Exercise Test; Hemoglobin A - genetics; Hemoglobin A - metabolism; Hemoglobin, Sickle - genetics; Hemoglobin, Sickle - metabolism; Heterozygote; Humans; Life Sciences; Male; Microcirculation; Muscle Contraction; Muscle Fibers, Skeletal - metabolism; Muscle Fibers, Skeletal - pathology; Muscle Strength; Muscle, Skeletal - blood supply; Muscle, Skeletal - metabolism; Muscle, Skeletal - pathology; Muscle, Skeletal - physiopathology; Musculoskeletal system; Physical Endurance; Regional Blood Flow; Sedentary Lifestyle; Sickle cell disease; Sickle Cell Trait - blood; Sickle Cell Trait - genetics; Sickle Cell Trait - metabolism; Sickle Cell Trait - pathology; Sickle Cell Trait - physiopathology; Surface area; Time Factors; Young Adult
• ISSN: 8750-7587; 1522-1601; 1522-1601
• DOI: 10.1152/japplphysiol.01573.2011

To assess the effects of regular physical activity on muscle functional characteristics of carriers of sickle cell trait (SCT), 39 untrained (U) and trained (T) hemoglobin (Hb)AA (CON) and SCT subjects (U-CON, n = 12; U-SCT, n = 8; T-CON, n = 10; and T-SCT, n = 9) performed a graded exercise and a time to exhaustion (T ex ) test, and were subjected to a muscle biopsy. Maximal power, total work performed during T ex , citrate synthase and cytochrome c oxidase (COX) activities, respiratory chain complexes I and IV content, and capillary density (CD), diameter (COD), and surface area (CSA) were upregulated by the same proportion in T-CON and T-SCT compared with their untrained counterparts. These proportionally similar differences imply that the observed discrepancies between U-SCT and U-CON remained in the trained subjects. Specifically, both CD and COX remained and tended to remain lower, and both COD and CSA remained and tended to remain higher in T-SCT than in T-CON. Besides, carriers of SCT displayed specific adaptations with regular physical activity: creatine kinase activity; complexes II, III, and V content; and type I fiber surface area and capillary tortuosity were lower or unchanged in T-SCT than in U-SCT. In summary, our results show that 1) carriers of SCT adapted almost similarly to CON to regular physical activity for most of the studied muscle characteristics, 2) oxidative potential remains altered in physically active carriers of SCT compared with HbAA counterparts, and 3) the specific remodeling of muscle microvascular network persists in the trained state.