Inhibition of lipopolysaccharide-induced osteoclast formation and bone resorption in vitro and in vivo by cysteine proteinase inhibitors

Journal of Leukocyte Biology: An Official Publication of the Reticuloendothelial Society

Grubb, Anders¹  Lerner, Ulf H.¹  Kasprzykowski, Franciszek²  Abrahamson, Magnus⁴  Kassem, Ali⁷  Lindholm, Catharina⁹ 

[1] University, Umeåand..Departments of Internal Medicine and Clinical Nutrition, Centre for Bone and Arthritis Research, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden;, Sweden;..Departments of Internal Medicine and Clinical Nutrition, Centre for Bone and Arthritis Research, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden;Department of Laboratory Medicine, Division of Clinical Chemistry and Pharmacology, Lund University, Lund, Sweden;Department of Molecular Periodontology, UmeåDepartment of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden;Institute of Chemistry, University of Gdansk, Gdansk, Poland

关键词: inflammation;    cystatin C;    macrophages;    periodontitis;    rheumatoid arthritis;   

学科分类：生理学

来源: Federation of American Societies for Experimental Biology

【 摘 要 】

Inflammation-induced bone destruction is a major treatment target in many inflammatory skeletal diseases. The aim of this study was to investigate if the cysteine proteinase inhibitors cystatin C, fungal cysteine proteinase inhibitor (E-64), and N-benzyloxycarbonyl-arginyl-leucyl-valyl-glycyl-diazomethane acetate (Z-RLVG-CHN₂) can inhibit LPS-induced osteoclast formation. Mouse bone marrow macrophages (BMMs) were isolated and primed with receptor activator of NF-κB ligand (RANKL) for 24 h, followed by stimulation with LPS, with and without inhibitors. Adult mice were injected locally with LPS and then treated with E-64 and osteoclast formation assessed by the number of cathepsin K⁺ multinucleated cells. Cystatin C inhibited LPS-induced osteoclast formation time and concentration dependently (IC₅₀ = 0.3 μM). The effect was associated with decreased mRNA and protein expression of tartrate-resistant acid phosphatase (TRAP) and cathepsin K and of the osteoclastogenic transcription factors c-Fos and NFATc1. LPS-induced osteoclast formation on bone slices was also inhibited by cystatin C, resulting in decreased pit formation and release of bone matrix proteins. Similar data were obtained with E-64 and Z-RLVG-CHN₂. Cystatin C was internalized in BMMs stimulated by LPS but not in unstimulated BMMs. Osteoclast formation induced by LPS was dependent on TNF-α, and the 3 inhibitors abolished LPS-induced TNF superfamily 2 (gene encoding TNF-α; Tnfsf2) mRNA expression without affecting Il1b, Il6, or oncostatin M (Osm) expression. Formation of osteoclasts in the skull bones after local LPS stimulation was inhibited by E-64. It is concluded that cysteine proteinase inhibitors effectively inhibit LPS-induced osteoclast formation in vivo and in vitro by inhibition of TNF-α expression. The targeting of cysteine proteinases might represent a novel treatment modality for prevention of inflammatory bone loss.

【 授权许可】

CC BY