This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Nakchbandi, I. A. Articles by Insogna, K. L. Search for Related Content PubMed PubMed Citation Articles by Nakchbandi, I. A. Articles by Insogna, K. L. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Hazardous Substances DB PARATHYROID HORMONE

IL-6 Negatively Regulates IL-11 Production in Vitro and in Vivo

Department of Medicine, Yale University School of Medicine, New Haven, Connecticut 06520-8020

Address all correspondence and requests for reprints to: Karl Insogna, M.D., Section of Endocrinology, Department of Medicine, Yale University School of Medicine, 333 Cedar Street, FMP 106, P.O. Box 208020, New Haven, Connecticut 06520-8020. E-mail: karl.insogna{at}yale.edu

IL-6 and IL-11 are two cytokines that increase osteoclast formation and augment bone resorption. PTH stimulates the production of both cytokines by human osteoblast-like cells. Circulating levels of IL-6 are elevated in patients with states of PTH excess and correlate strongly to markers of bone resorption. In contrast, serum levels of IL-11 were significantly reduced in patients with primary hyperparathyroidism compared with values in euparathyroid controls. Further, after successful parathyroid adenomectomy, circulating levels of IL-6 fell, whereas IL-11 levels increased. Five-day infusions of human PTH-(1–84) in rodents resulted in a significant decline in mean circulating levels of IL-11, whereas IL-6 levels significantly increased. Pretreatment of cells and mice with neutralizing serum to IL-6 enhanced PTH-induced IL-11 production compared with the effect of pretreatment with nonimmune sera. These data indicate that IL-6 negatively regulates IL-11 production in vivo and in vitro. Analysis of steady state mRNA levels in SaOS-2 cells indicated that this effect is posttranscriptional. As both IL-6 and IL-11 stimulate osteoclast formation, down-regulation of IL-11 by IL-6 may help modulate the resorptive response to PTH.

This article has been cited by other articles:

				U. S. Masiukiewicz, M. Mitnick, B. I. Gulanski, and K. L. Insogna Evidence that the IL-6/IL-6 Soluble Receptor Cytokine System Plays a Role in the Increased Skeletal Sensitivity to PTH in Estrogen-Deficient Women J. Clin. Endocrinol. Metab., June 1, 2002; 87(6): 2892 - 2898. [Abstract] [Full Text] [PDF]