title: Effects of intermittent hypoxia and light aerobic exercise on circulating stem cells and side population, after strenuous eccentric exercise in trained rats.
abstract: Our goal was to address if intermittent hypobaric hypoxia (IHH) exposure can help to increase the number of peripheral blood circulating progenitor cells and side population (SP) stem cells, in order to establish the usefulness of this intervention for skeletal muscle repair, because these cells play a role in tissue regeneration. Male Sprague-Dawley rats were studied in two basal states: untrained and trained and compared with 1, 3, 7 and 14 days stages of damage recovery of trained rats that had suffered skeletal muscle injury. Three experimental groups were studied: rats with passive recovery (CTRL); rats exposed to IHH after muscle damage (HYP); and, trained rats that, in addition to IHH, performed light aerobic exercise sessions (EHYP). We observed an increase in hematopoietic stem cells (HSCs) (mean = 0.153% of cells) and endothelial progenitor cells (EPCs) (mean = 0.0020% of cells) in EHYP on day 7. Also these cells showed characteristics of more primitive progenitors in comparison to the other experimental groups (mean = 0.107% of cells), as deduced by retention of the promising fluorescent probe Vybrant Dye Cycle Violet. We concluded that intermittent exposure to hypobaric hypoxia in combination with light aerobic exercise increased the number of HSCs and EPCs on the 7th day in EHYP group, although the exercise-induced stimulus showed a reverse effect on SP kinetics.
authors.forename: Cristian
authors.initials: C
authors.lastname: Núñez-Espinosa
authors.forename: Inês
authors.initials: I
authors.lastname: Ferreira
authors.forename: Juan Gabriel
authors.initials: JG
authors.lastname: Ríos-Kristjánsson
authors.forename: David
authors.initials: D
authors.lastname: Rizo-Roca
authors.forename: Maria Dolors
authors.initials: MD
authors.lastname: García Godoy
authors.forename: Laura G
authors.initials: LG
authors.lastname: Rico
authors.forename: Gerard
authors.initials: G
authors.lastname: Rubi-Sans
authors.forename: Joan Ramon
authors.initials: JR
authors.lastname: Torrella
authors.forename: Teresa
authors.initials: T
authors.lastname: Pagès
authors.forename: Jordi
authors.initials: J
authors.lastname: Petriz
authors.forename: Ginés
authors.initials: G
authors.lastname: Viscor
mesh_terms: D000818:Animals; D018952:Antigens, CD34 / Q000378:metabolism; D015687:Cell Hypoxia; D006412:Hematopoietic Stem Cells / Q000502:physiology*; D008297:Male; D010805:Physical Conditioning, Animal; D005082:Physical Exertion; D017207:Rats, Sprague-Dawley; D017463:Receptors, Complement 3b / Q000378:metabolism; D058985:Side-Population Cells / Q000502:physiology*
chemical_list: D018952:Antigens, CD34; D017463:Receptors, Complement 3b