Reference

IL-1b synthesis by chondrocyte analyzed by 3D microscopy and flow cytometry: Effect of Rhein

All Rights Reserved. IL-1b synthesis by chondrocyte analyzed by 3D microscopy and flow cytometry: Effect of Rhein. Stoltz, J. F.; de Isla, N. G.; Yang, J. W.; Huselstein, C.; Muller, S.; Stoltz, J. F. (Lemta, Faculte de Medecine, Mecanique et Ingenierie Cellulaire et Tissulaire, Vandoeuvre-le s-Nancy, Fr.). Biorheology, 43(3,4), 595-601 (English) 2006 IOS Press. CODEN: BRHLAU. ISSN: 0006-355X. 478-43-3 and 13739-02-1 which are cas registry numbers are also used here. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacology) Section cross-reference(s): 15 Several factors are known to be involved in the destruction of the articular cartilage. Interleukin-1 (IL-1) plays an important role in the pathogenesis of osteoarthritis (OA) either directly or through the stimulation of catabolic factors. The action of IL-1 on articular cartilage is multifaceted and it most likely plays an important role in the mechanism of cartilage destruction. IL-1 suppresses the synthesis of the cartilage matrix components and promotes the degrdn. of cartilage matrix macromols. Diacerein is an anthraquinone mol. that has been shown to reduce the severity of OA, both in man and in animal models. The present study was designed to evaluate in vitro effects of diacerein on IL-1b expression in LPS or IL-1a stimulated chondrocytes. Intracellular IL-1b prodn. was analyzed in articular chondrocytes cultured in monolayer or in alginate 3D-biosystems in the presence of lipopolysaccharide (LPS) or IL-1a, with or without diacerein. The results show that LPS and IL-1a increase intracellular IL-1b and Diacerein inhibited LPS-induced and IL-1a induced IL-1b prodn. by articular chondrocytes. Moreover, the effect of mech. stimulation was analyzed. An inhibitory effect of DAR at therapeutic concns. on IL-1b prodn. in articular chondrocytes is suggested. .

Diacerhein and rhein prevent interleukin-1b-induced nuclear factor-kB activation by inhibiting the degradation of inhibitor kB-a

Diacerhein and rhein prevent interleukin-1b-induced nuclear factor-kB activation by inhibiting the degradation of inhibitor kB-a. Mendes, Alexandrina Ferreira; Caramona, Maria Margarida; Pato De Carvalho, Arselio; Lopes, Maria Celeste (Faculty of Pharmacy and Centre for Neurosciences of Coimbra, Department of Zoology, University of Coimbra, Coimbra 3000-295, Port.). Pharmacology & Toxicology (Oxford, United Kingdom), 91(1), 22-28 (English) 2002 Blackwell Publishers Ltd. CODEN: PHTOEH. ISSN: 0901-9928. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacology) Diacerhein and rhein are anthraquinone compds. that ameliorate the course of osteoarthritis. Recent reports also suggest that these compds. may have antiinflammatory properties, but the cellular mechanisms by which they exert antiosteoarthritic and possibly antiinflammatory effects are still incompletely understood. The purpose of this study was to investigate the ability of diacerhein and rhein to inhibit the activation of the transcription factor nuclear factor-kB, induced by the proinflammatory cytokine interleukin-1b, in primary monolayer cultures of bovine articular chondrocytes. We also studied the ability of diacerhein and rhein to prevent the expression of the inducible nitric oxide synthase gene, which is driven by nuclear factor-kB. We obsd. that interleukin-1b induced the degrdn. of the inhibitor kB-a protein and the translocation of the protein p65 (a member of the nuclear factor-kB family) to the nucleus, which were inhibited by diacerhein and rhein, in a dose-dependent manner. Interleukin-1b-induced nuclear factor-kB binding to a specific (g-32P)-labeled oligonucleotide probe was also inhibited by treatment of chondrocytes with diacerhein or rhein, as revealed by electrophoretic mobility shift assay. Inducible nitric oxide synthase mRNA and protein synthesis and nitric oxide prodn. were also inhibited by diacerhein and rhein, in a dose-dependent manner. The half-maximal inhibitory concns. of diacerhein and rhein, relative to nitric oxide prodn., were 8.In this experiment, several chemicals are used like 478-43-3 and 13739-02-1 2 mM and 7.7 mM, resp. These results suggest that diacerhein and rhein inhibit nuclear factor-kB activation and, consequently, the expression of nuclear factor-kB-dependent genes, such as the inducible nitric oxide synthase gene, which can explain their antiosteoarthritic and antiinflammatory effects. .