title: IL-17A-mediated sRANK ligand elevation involved in postmenopausal osteoporosis.
abstract: The role of proinflammatory IL-17 cytokine was studied in postmenopausal bone loss between 31 osteopenic and 41 osteoporotic women. The effect of serum IL-17A, soluble receptor activator of NF-κB (sRANK) ligand, and osteoprotegerin (OPG) levels on lumbar bone mineral densities was measured. The results demonstrated an increased IL-17A-mediated sRANK ligand elevation in postmenopausal osteoporotic bone loss.
  
  
  BACKGROUND
  IL-17 proinflammatory cytokine is a new inducer of bone loss. Postmenopausal osteoporosis represents a cross talk between estrogen deprivation and increased immune reactivity. The role of IL-17 was studied in the bone loss of postmenopausal osteoporosis.
  
  
  METHODS
  Serum IL-17A, sRANK ligand, and OPG levels were investigated on bone mineral densities (BMDs) in the total lumbar (L1-L4) region in 18 pre- and 72 postmenopausal women. IL-17A, sRANK ligand, OPG levels, and BMDs were measured with enzyme-linked immunosorbent assay (ELISA) and dual-energy X-ray absorptiometry (DXA).
  
  
  RESULTS
  Increased serum IL-17A, sRANK ligand, and OPG levels were demonstrated in postmenopausal osteoporotic women compared to osteopenic women (3.65 ± 0.61 vs 3.31 ± 0.43 ng/ml for IL-17A, P < 0.007; 2.88 ± 0.84 vs 2.49 ± 0.61 ng/ml for sRANK ligand, P < 0.027; and 1.43 ± 0.07 vs 1.39 ± 0.07 ng/ml for OPG, P < 0.038). In postmenopausal women, IL-17A levels correlated inversely with total lumbar BMDs (P < 0.008, r = -0.279) and positively with sRANK ligand levels (P < 0.0001, r = 0.387) or the ratio of sRANK ligand and OPG (P < 0.013, r = 0.261), but did not with OPG levels alone.
  
  
  CONCLUSIONS
  Increased IL-17A levels are involved in postmenopausal osteoporosis, playing a role in the bone-resorpting processes.
authors: Immunoendocrinology and Osteoporosis Centre, EndoMed, Bem tér 18/C, 4026, Debrecen, Hungary, molil@endomed.hu.
authors: I
authors: I
authors: Molnár
authors: I
authors: I
authors: Bohaty
authors: É
authors: É
authors: Somogyiné-Vári
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density / Q000502:physiology; D001851:Bone Diseases, Metabolic / Q000097:blood / Q000503:physiopathology; D005260:Female; D006801:Humans; D020381:Interleukin-17 / Q000502:physiology*; D008159:Lumbar Vertebrae / Q000503:physiopathology; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000097:blood* / Q000503:physiopathology; D053244:Osteoprotegerin / Q000097:blood; D017697:Premenopause / Q000502:physiology; D053245:RANK Ligand / Q000097:blood*
chemical_list: C508717:IL17A protein, human; D020381:Interleukin-17; D053244:Osteoprotegerin; D053245:RANK Ligand; C506030:TNFRSF11B protein, human