title: AZT enhances osteoclastogenesis and bone loss.
abstract: A variety of metabolic complications have been reported to be associated with highly active antiretroviral therapy (HAART), including osteopenia and osteoporosis. In this study, we determine the effects of zidovudine (AZT), a nucleoside reverse transcriptase inhibitor, on osteoclastogenesis in a cultured mouse macrophage preosteoclast cell line (RAW264.7), in mouse primary bone marrow macrophage-monocyte precursors, and on bone mineral density in mice. The results indicate that AZT induces an increase in osteoclastogenesis in the mouse preosteoclast cell line and in mouse bone marrow osteoclast precursors in the presence of RANKL. This increased osteoclastogenesis is dependent upon the concentration of AZT. AZT increases the promoter activity of tartrate-resistant acid phosphatase (TRAP) and the binding and function of the nuclear transcription protein, NF-kappaB, in RAW264.7 cells. Therefore, the effect of AZT is mediated, at least in part, by enhancing RANKL-mediated osteoclastogenesis. Bone mineral density (BMD) in AZT-treated mice is decreased and histopathology shows marked osteopenia. These results support an important role of AZT-stimulated osteoclastogenesis in HAART-induced osteopenia.
authors.affiliation: The Department of Pathology, The University of Alabama at Birmingham, 35294-0007,USA.
authors.forename: George
authors.initials: G
authors.lastname: Pan
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Wu
authors.forename: Margaret A
authors.initials: MA
authors.lastname: McKenna
authors.forename: Xu
authors.initials: X
authors.lastname: Feng
authors.forename: Tim R
authors.initials: TR
authors.lastname: Nagy
authors.forename: Jay M
authors.initials: JM
authors.lastname: McDonald
mesh_terms: D000135:Acid Phosphatase / Q000235:genetics; D000818:Animals; D019380:Anti-HIV Agents / Q000494:pharmacology* / Q000627:therapeutic use; D015519:Bone Density / Q000187:drug effects*; D001842:Bone and Bones / Q000473:pathology; D002352:Carrier Proteins / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D002478:Cells, Cultured; D005786:Gene Expression Regulation / Q000187:drug effects; D015658:HIV Infections / Q000188:drug therapy; D007527:Isoenzymes / Q000235:genetics; D008562:Membrane Glycoproteins / Q000494:pharmacology; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism; D010010:Osteoclasts / Q000166:cytology / Q000187:drug effects*; D011401:Promoter Regions, Genetic / Q000187:drug effects; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D000071681:Tartrate-Resistant Acid Phosphatase; D015215:Zidovudine / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D019380:Anti-HIV Agents; D002352:Carrier Proteins; D007527:Isoenzymes; D008562:Membrane Glycoproteins; D016328:NF-kappa B; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; C505687:Tnfrsf11a protein, mouse; C505689:Tnfsf11 protein, mouse; D015215:Zidovudine; D000135:Acid Phosphatase; C000605511:Acp5 protein, mouse; D000071681:Tartrate-Resistant Acid Phosphatase