TY - JOUR A2 - Reichner, Jonathan S. AU - Kitaura, Hideki AU - Ishida, Masahiko AU - Kimura, Keisuke AU - Sugisawa, Haruki AU - Kishikawa, Akiko AU - Shima, Kazuhiro AU - Ogawa, Saika AU - Qi, Jiawei AU - Shen, Wei-Ren PY - 2018 DA - 2018/02/14 TI - Role of Muramyl Dipeptide in Lipopolysaccharide-Mediated Biological Activity and Osteoclast Activity SP - 8047610 VL - 2018 AB - Lipopolysaccharide (LPS) is an endotoxin and bacterial cell wall component that is capable of inducing inflammation and immunological activity. Muramyl dipeptide (MDP), the minimal essential structural unit responsible for the immunological activity of peptidoglycans, is another inflammation-inducing molecule that is ubiquitously expressed by bacteria. Several studies have shown that inflammation-related biological activities were synergistically induced by interactions between LPS and MDP. MDP synergistically enhances production of proinflammatory cytokines that are induced by LPS exposure. Injection of MDP induces lethal shock in mice challenged with LPS. LPS also induces osteoclast formation and pathological bone resorption; MDP enhances LPS induction of both processes. Furthermore, MDP enhances the LPS-induced receptor activator of NF- κB ligand (RANKL) expression and toll-like receptor 4 (TLR4) expression both in vivoand in vitro。此外,MDP增强LPS-induced mitogen-activated protein kinase (MAPK) signaling in stromal cells. Taken together, these findings suggest that MDP plays an important role in LPS-induced biological activities. This review discusses the role of MDP in LPS-mediated biological activities, primarily in relation to osteoclastogenesis. SN - 2210-7177 UR - https://doi.org/10.1155/2018/8047610 DO - 10.1155/2018/8047610 JF - Analytical Cellular Pathology PB - Hindawi KW - ER -