title: Plasminogen activator inhibitor-1 (PAI-1): a key factor linking fibrinolysis and age-related subclinical and clinical conditions.
abstract: BACKGROUND
  The close relationship existing between aging and thrombosis has growingly been studied in this last decade. The age-related development of a prothrombotic imbalance in the fibrinolysis homeostasis has been hypothesized as the basis of this increased cardiovascular and cerebrovascular risk. Fibrinolysis is the result of the interactions among multiple plasminogen activators and inhibitors constituting the enzymatic cascade, and ultimately leading to the degradation of fibrin. The plasminogen activator system plays a key role in a wide range of physiological and pathological processes.
  
  
  METHODS
  Narrative review.
  
  
  RESULTS
  Plasminogen activator inhibitor-1 (PAI-1) is a member of the superfamily of serine-protease inhibitors (or serpins), and the principal inhibitor of both the tissue-type and the urokinase-type plasminogen activator, the two plasminogen activators able to activate plasminogen. Current evidence describing the central role played by PAI-1 in a number of age-related subclinical (i.e., inflammation, atherosclerosis, insulin resistance) and clinical (i.e., obesity, comorbidities, Werner syndrome) conditions is presented.
  
  
  CONCLUSIONS
  Despite some controversial and unclear issues, PAI-1 represents an extremely promising marker that may become a biological parameter to be progressively considered in the prognostic evaluation, in the disease monitoring, and as treatment target of age-related conditions in the future.
authors.affiliation: Area di Geriatria, Università Campus Bio-Medico, Rome, Italy. macesari@gmail.com
authors.forename: Matteo
authors.initials: M
authors.lastname: Cesari
authors.forename: Marco
authors.initials: M
authors.lastname: Pahor
authors.forename: Raffaele Antonelli
authors.initials: RA
authors.lastname: Incalzi
mesh_terms: D000367:Age Factors; D000375:Aging / Q000097:blood*; D000818:Animals; D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000097:blood / Q000209:etiology*; D019317:Evidence-Based Medicine; D005342:Fibrinolysis; D006801:Humans; D017395:Plasminogen Activator Inhibitor 1 / Q000097:blood*; D018570:Risk Assessment; D012307:Risk Factors; D015398:Signal Transduction
chemical_list: D015415:Biomarkers; D017395:Plasminogen Activator Inhibitor 1; C051321:SERPINE1 protein, human