title: The expression of vascular endothelial growth factor in skeletal muscle of patients with sleep disorders.
abstract: An increased capillary network has been observed in skeletal muscle of patients with restless legs syndrome (RLS) and obstructive sleep apnea syndrome (OSAS). This finding could be due to upregulation of growth factors responsible for angiogenesis. The aim of the study was to examine the occurrence and localization of VEGF and capillary proliferation in skeletal muscle of RLS (n = 12) and OSAS (n = 12) patients and controls (n = 11). Double-immunofluorescence staining for capillaries (CD31) and VEGF, and proliferating cells (Ki-67), was carried out on biopsies taken from the tibialis anterior. The percentage of capillaries expressing VEGF (CD31,VEGF(+)) was significantly higher in OSAS and RLS patients compared with controls. The percentage of proliferating capillaries (CD31,Ki-67(+)) was significantly higher in OSAS patients compared with controls. Our study shows the occurrence of proliferation of endothelial cells in skeletal muscle in RLS and OSAS, supporting an upregulation of VEGF located in capillaries, probably due to local hypoxia.
authors.affiliation: School of Health and Medical Sciences, Orebro University, Orebro, Sweden. bwl@du.se
authors.forename: Britta
authors.initials: B
authors.lastname: Wåhlin-Larsson
authors.forename: Jan
authors.initials: J
authors.lastname: Ulfberg
authors.forename: Karin Piehl
authors.initials: KP
authors.lastname: Aulin
authors.forename: Fawzi
authors.initials: F
authors.lastname: Kadi
mesh_terms: D000328:Adult; D001706:Biopsy; D002196:Capillaries / Q000378:metabolism; D042783:Endothelial Cells / Q000378:metabolism; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D018656:Muscle Fibers, Fast-Twitch / Q000378:metabolism; D018657:Muscle Fibers, Slow-Twitch / Q000378:metabolism; D018482:Muscle, Skeletal / Q000166:cytology / Q000378:metabolism*; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D012016:Reference Values; D012148:Restless Legs Syndrome / Q000378:metabolism; D020181:Sleep Apnea, Obstructive / Q000378:metabolism; D012893:Sleep Wake Disorders / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis*
chemical_list: D019394:Ki-67 Antigen; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D042461:Vascular Endothelial Growth Factor A