title: Osteoprotegerin and RANKL in alcoholic liver cirrhosis.
abstract: OBJECTIVE
  The mechanisms leading to osteoporosis in alcoholic liver disease remain poorly understood. Recently identified soluble circulating osteoprotegerin (OPG), is the osteoclastogenesis inhibitory factor. It acts as a decoy receptor for osteoclast activating factor, receptor activator of nuclear factor-kappaB ligand (RANKL), and impairs osteoclast function. The aim of our study was to investigate the OPG/RANKL system in alcoholic cirrhotic patients and their correlation with biochemical marker of bone turnover.
  
  
  METHODS
  Serum OPG, RANKL, osteocalcin (OC), C-terminal cross-linking telopeptide of type I collagen (CTX-I), bone alkaline phosphatase activity (bALP), and urinary hydroxyproline were measured in 30 patients with alcoholic cirrhosis, and in 20 age- and sex-matched healthy controls.
  
  
  RESULTS
  OPG levels were significantly increased in patients with alcoholic cirrhosis compared with healthy subjects (5.9 pmol/l, range 2.7-9.0 vs 4.1 pmol/l, range 1.2-6.6; P < 0.001). RANKL levels were significantly higher in patients with cirrhosis (0.48 pmol/l, range 0.01-1.34) than in healthy subjects (0.11 pmol/l, range 0.01-0.90). There was a positive correlation between serum OPG and RANKL (r = 0.37; P < 0.001), bALP (r = 0.66; P < 0.001) and urinary hydroxyproline (r = 0.51; P < 0.05) but not with OC and CTX-I.
  
  
  CONCLUSIONS
  OPG might partly represent a compensating mechanism to the negative balance of bone remodelling in patients with alcoholic cirrhosis.
authors.affiliation: Gastroenterology and Hepatology Unit, Faculty of Medicine, University Hospital Marqués de Valdecilla, U.C. Santander, Avenida Valdecilla s/n, 39008 Santander, Cantabria, Spain. digfge@humv.es
authors.forename: Emilio
authors.initials: E
authors.lastname: Fábrega
authors.forename: Aitor
authors.initials: A
authors.lastname: Orive
authors.forename: Covadonga
authors.initials: C
authors.lastname: García-Suarez
authors.forename: Maite
authors.initials: M
authors.lastname: García-Unzueta
authors.forename: Jose
authors.initials: J
authors.lastname: Antonio Amado
authors.forename: Fernando
authors.initials: F
authors.lastname: Pons-Romero
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001707:Biopsy, Needle; D002352:Carrier Proteins / Q000097:blood* / Q000378:metabolism; D016022:Case-Control Studies; D018450:Disease Progression; D005260:Female; D006023:Glycoproteins / Q000097:blood* / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008104:Liver Cirrhosis, Alcoholic / Q000097:blood / Q000175:diagnosis*; D008111:Liver Function Tests; D008297:Male; D008562:Membrane Glycoproteins / Q000097:blood* / Q000378:metabolism; D008875:Middle Aged; D053244:Osteoprotegerin; D011336:Probability; D011379:Prognosis; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear / Q000097:blood* / Q000378:metabolism; D018124:Receptors, Tumor Necrosis Factor / Q000097:blood* / Q000378:metabolism; D012016:Reference Values; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D002352:Carrier Proteins; D006023:Glycoproteins; D008562:Membrane Glycoproteins; D053244:Osteoprotegerin; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; C505686:TNFRSF11A protein, human; C506030:TNFRSF11B protein, human; C505688:TNFSF11 protein, human