tailieunhanh - Báo cáo y học: "Human articular chondrocytes express ChemR23 and chemerin; ChemR23 promotes inflammatory signalling upon binding the ligand chemerin21-157"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học General Psychiatry cung cấp cho các bạn kiến thức về ngành y đề tài: Human articular chondrocytes express ChemR23 and chemerin; ChemR23 promotes inflammatory signalling upon binding the ligand chemerin21-157. | Berg et al. Arthritis Research Therapy 2010 12 R228 http content 12 6 R228 RESEARCH ARTICLE Open Access Human articular chondrocytes express ChemR23 and chemerin ChemR23 promotes inflammatory signalling upon binding the ligand chemerin21-157 1 4 6 Vivian Berg Baldur Sveinbjornsson Signy Bendiksen Jan Brox 1 Khaled Meknas Yngve Figenschau 1 Abstract Introduction Chemerin is a chemotactic peptide which directs leukocytes expressing the chemokine-like receptor ChemR23 towards sites of inflammation. ChemR23 is a G protein-coupled receptor which binds several different ligands and it is also expressed by other cell types such as adipocytes. In addition to chemotaxis recent reports suggest that ChemR23 is capable of mediating either inflammatory or anti-inflammatory effects depending on the type of ligand it binds. In the present study we aimed to clarify whether human chondrocytes express ChemR23 and chemerin and whether chemerin ChemR23 signalling could affect secretion of inflammatory mediators. Methods Tissue sections were taken from human knee joints and labelled with antibodies towards chemerin and ChemR23. Chondrocytes from cartilage tissue were isolated cultured and assessed for chemerin and ChemR23 expression by PCR and immunolabelling. Receptor activation and intracellular signalling were studied by assessment of phosphorylated mitogen activated protein kinases MAPKs and phosphorylated Akt after stimulating cells with recombinant chemerin21-157. Biological effects of chemerin21-157 were investigated by measuring secretion of pro-inflammatory cytokines and metalloproteases in cell supernatants. Results Both serially cultured human articular chondrocytes and resident cells in native cartilage expressed chemerin and ChemR23. Stimulating cells with chemerin21-157 resulted in phosphorylation of p44 p42 MAPKs ERK 1 2 and Akt Ser 473 . Also significantly enhanced levels of the pro-inflammatory cytokines interleukin-6 IL-6 .