1,25(OH)2 vitamin D3-stimulated osteoclast formation in spleen-osteoblast cocultures is mediated in part by enhanced IL-1 alpha and receptor activator of NF-kappa B ligand production in osteoblasts.
We examined the ability of 1,25 (OH)(2) vitamin D(3) (Vit D) to stimulate osteoclast-like cell (OCL) formation in cocultures of spleen cells and primary calvarial osteoblasts from wild-type (WT) and IL-1R type 1-deficient (knockout; KO) mice. Vit D dose dependently increased OCL in cocultures containing WT osteoblasts. In contrast, there was a 90% reduction in OCL numbers in cocultures containing KO osteoblasts. In cocultures with either WT or KO osteoblasts, treatment with Vit D increased receptor activator of NF-kappaB ligand mRNA by 17-, 19-, or 3.5-fold, respectively. Vit D decreased osteoprotegerin mRNA to undetectable in all groups. Intracellular IL-1alpha protein increased after Vit D treatment in cocultures containing WT, but not KO osteoblasts. We also examined direct effects of Vit D, IL-1alpha, and their combination on gene expression in primary osteoblasts. In WT cells, Vit D and IL-1 stimulated receptor activator of NF-kappaB ligand mRNA expression by 3- and 4-fold, respectively, and their combination produced a 7-fold increase. Inhibition of osteoprotegerin mRNA in WT cells was partial with either agent alone and greatest with their combination. In KO cells, only Vit D stimulated a response. IL-1 alone increased IL-1alpha protein expression in WT osteoblasts. However, in combination with Vit D, there was a synergistic response (100-fold increase). In KO cultures, there were no effects of IL-1, Vit D, or their combination on IL-1alpha protein. These results demonstrate interactions between IL-1 and Vit D in primary osteoblasts that appear important in both regulation of IL-1alpha production and the ability of Vit D to support osteoclastogenesis.
Lee
Sun-Kyeong
SK
Division of Endocrinology, Department of Medicine, University of Connecticut Health Center, Farmington 06030, USA. slee@neuron.uchc.edu
Kalinowski
Judy
J
Jastrzebski
Sandra
S
Lorenzo
Joseph A
JA
D000276:Adjuvants, Immunologic / Q000096:biosynthesis / Q000502:physiology; D000818:Animals; D002117:Calcitriol / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D002478:Cells, Cultured; D018920:Coculture Techniques; D006023:Glycoproteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1 / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D008024:Ligands; D008297:Male; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D016328:NF-kappa B / Q000378:metabolism; D010006:Osteoblasts / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D010010:Osteoclasts / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D010012:Osteogenesis / Q000187:drug effects* / Q000276:immunology; D053244:Osteoprotegerin; D053245:RANK Ligand; D012333:RNA, Messenger / Q000096:biosynthesis; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D018124:Receptors, Tumor Necrosis Factor; D012795:Sialoglycoproteins / Q000494:pharmacology; D013154:Spleen / Q000166:cytology* / Q000187:drug effects / Q000502:physiology
D000276:Adjuvants, Immunologic; D002352:Carrier Proteins; D006023:Glycoproteins; C507764:Il1rn protein, mouse; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1; D008024:Ligands; D008562:Membrane Glycoproteins; D016328:NF-kappa B; D053244:Osteoprotegerin; D053245:RANK Ligand; D012333:RNA, Messenger; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; D012795:Sialoglycoproteins; C505687:Tnfrsf11a protein, mouse; C506031:Tnfrsf11b protein, mouse; C505689:Tnfsf11 protein, mouse; D002117:Calcitriol