title: The clinical relevance of altered fibrinogen packaging in the presence of 17β-estradiol and progesterone.
abstract: BACKGROUND
  The effect of endogenous hormone concentrations, specifically 17β-estradiol and progesterone, on fibrin network formation has not been established.
  
  
  OBJECTIVE
  It is essential to understand natural hormone mechanisms since these hormones are still present in circulation while hormonal contraceptives, which are associated with increased risk of venous thromboembolism, are used.
  
  
  METHODS
  Due to the fact that these hormones are known to increase hypercoagulability and the prothrombotic state scanning electron microscopy (SEM), atomic force microscopy (AFM), thromboelastography (TEG) and turbidimetry were employed to investigate the morphology, surface roughness, viscoelastic properties and formation and lysis of fibrin.
  
  
  RESULTS
  17β-estradiol and progesterone showed hypercoagulable viscoelastic properties and decreased the diameter and surface roughness of fibrin while increasing dense matted deposit occurrence. Our results suggest that the additional burden of hormonal load, together with the presence of endogenous estrogen and progesterone, may result in a prothrombotic and hypercoagulable state in females with an inflammatory predisposition.
  
  
  CONCLUSIONS
  Our results are of clinical importance when considering hormones as either pathological agent or therapeutic intervention as will be assessed in future investigation.
authors: Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, South Africa. Electronic address: albe.swanepoel@up.ac.za.
authors: Albe C
authors: AC
authors: Swanepoel
authors: Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, South Africa.
authors: Amcois
authors: A
authors: Visagie
authors: Centre of Excellence for Nutrition, North-West University, Potchefstroom, South Africa.
authors: Zelda
authors: Z
authors: de Lange
authors: Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, South Africa.
authors: Odette
authors: O
authors: Emmerson
authors: The Department of Anaesthesiology, The University of Arizona College of Medicine, Tucson, AZ, USA.
authors: Vance G
authors: VG
authors: Nielsen
authors: Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, South Africa.
authors: Etheresia
authors: E
authors: Pretorius
mesh_terms: D004958:Estradiol / Q000378:metabolism*; D005260:Female; D005340:Fibrinogen / Q000378:metabolism*; D006801:Humans; D011374:Progesterone / Q000378:metabolism*
chemical_list: D011374:Progesterone; D004958:Estradiol; D005340:Fibrinogen
keywords: 17β-estradiol; Fibrin; Fibrinogen; Progesterone; Thrombophilia