title: Sirtuin 1 activity in peripheral blood mononuclear cells of patients with osteoporosis.
abstract: BACKGROUND
  Sirtuin 1 (SIRT1) is a class III histone deacetylase that may play a critical role in several biological functions, including lifespan, stress, and inflammation. Our main objective was to evaluate SIRT1 activity in peripheral blood mononuclear cells (PBMCs) in patients with osteoporosis and to analyze the relationship between the SIRT 1 activity and markers of inflammation and bone remodelling.
  
  
  METHODS
  We performed a prospective monocentric study of patients with osteoporosis and measured the nuclear and cytoplasmic activities of SIRT1 in PBMCs. Levels of proinflammatory cytokines were assessed in culture supernatants of PBMCs isolated from the osteoporosis patients. The level of serum C-terminal cross-linking telopeptide of type I collagen (CTX), a marker of bone resorption, was measured in the serum of osteoporosis patients.
  
  
  RESULTS
  Sixteen women with osteoporosis were included. A statistically significant correlation between the cytoplasmic and nuclear SIRT 1 activities was found in PBMCs of patients with osteoporosis. Although non-significant, we observed a negative trend between nuclear SIRT 1 activity and the rate of serum CTX and a positive trend between IL-6 and CTX levels in patients with osteoporosis.
  
  
  CONCLUSIONS
  This study shows that the cytoplasmic and nuclear SIRT 1 activities are measurable in circulating PBMCs of patients with osteoporosis and that these 2 activities are correlated. The potential role of inflammation in bone resorption in patients with osteoporosis was also studied.
authors.affiliation: Department of Rheumatology, Centre Hospitalier Régional Universitaire (CHRU) Besançon, Besançon, France.
authors.forename: Marie
authors.initials: M
authors.lastname: Godfrin-Valnet
authors.affiliation: Pathogens & Inflammation Laboratory, University of Franche-Comté, Besançon, France.
authors.forename: Kashif A
authors.initials: KA
authors.lastname: Khan
authors.affiliation: Department of Rheumatology, Centre Hospitalier Régional Universitaire (CHRU) Besançon, Besançon, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Guillot
authors.affiliation: Department of Rheumatology, Centre Hospitalier Régional Universitaire (CHRU) Besançon, Besançon, France.
authors.forename: Clément
authors.initials: C
authors.lastname: Prati
authors.affiliation: Pathogens & Inflammation Laboratory, University of Franche-Comté, Besançon, France.
authors.forename: Lucile
authors.initials: L
authors.lastname: Baud
authors.affiliation: Pathogens & Inflammation Laboratory, University of Franche-Comté, Besançon, France.
authors.forename: Wasim
authors.initials: W
authors.lastname: Abbas
authors.affiliation: Department of Rheumatology, Centre Hospitalier Régional Universitaire (CHRU) Besançon, Besançon, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Toussirot
authors.affiliation: Department of Rheumatology, Centre Hospitalier Régional Universitaire (CHRU) Besançon, Besançon, France.
authors.forename: Daniel
authors.initials: D
authors.lastname: Wendling
authors.affiliation: Pathogens & Inflammation Laboratory, University of Franche-Comté, Besançon, France.
authors.forename: Georges
authors.initials: G
authors.lastname: Herbein
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D002467:Cell Nucleus / Q000378:metabolism; D024042:Collagen Type I / Q000097:blood; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000097:blood; D007963:Leukocytes, Mononuclear / Q000201:enzymology*; D010024:Osteoporosis / Q000097:blood* / Q000201:enzymology*; D010455:Peptides / Q000097:blood; D056564:Sirtuin 1 / Q000097:blood*
chemical_list: D024042:Collagen Type I; D015850:Interleukin-6; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D056564:Sirtuin 1