Extracellular Matrix Proteins

Joint replacement is a major orthopaedic procedure used to treat joint osteoarthritis. Aseptic loosening and infection are the two most significant causes of prosthetic implant failure. The ideal implant should be able to promote osteointegration, deter bacterial adhesion and minimize prosthetic infection. Recent developments in material science and cell biology have seen the development of new orthopaedic implant coatings to address these issues. Coatings consisting of bioceramics, extracellular matrix proteins, biological peptides or growth factors impart bioactivity and biocompatibility to the metallic surface of conventional orthopaedic prosthesis that promote bone ingrowth and differentiation of stem cells into osteoblasts leading to enhanced osteointegration of the implant. Furthermore, coatings such as silver, nitric oxide, antibiotics, antiseptics and antimicrobial peptides with anti-microbial properties have also been developed, which show promise in reducing bacterial adhe...

ObjectiveDiabetic nephropathy is a debilitating disease that leads to end-stage renal failure in the Western world. Hyperglycemia is the initiating factor in several chronic diabetic complications which mediates increased oxidative stress and eventually the increased production of vasoactive factors and extracellular matrix proteins. We hypothesized that curcumin, a potent antioxidant, might be beneficial in preventing the development of diabetic nephropathy

The pattern of expression and distribution of extracellular matrix (ECM) components in human cardiac leaflets was analyzed. Additionally, interstitial cells (ICs) from the four different leaflets were isolated and studied. Immunohistochemistry and immunocytochemistry were used for localization, and flow cytometric analysis to quantify the expression of specific markers on these ICs; the synthesis and expression of ECM components was assessed. Elastin was found predominantly on the inflow layer, but fine fibers were also present in the central and outflow layers. Collagen I was predominantly on the outflow layer but permeated throughout the leaflets. Collagen III was expressed ubiquitously. Proteoglycan expression was throughout the leaflet, but was predominant in the central layer. Fibronectin and vitronectin were expressed strongly in the inflow layer, moderately in the central layer, and weakly in the outflow layer. Biglycan expression was ubiquitous, with strong filamentous stran...

Comprehensive analysis of neuromuscular junction formation and recent data on synaptogenesis and long-term potentiation in the central nervous system revealed a number of extracellular matrix (ECM) molecules regulating different aspects of synaptic differentiation and function. The emerging mechanisms comprise interactions of ECM components with their cell surface receptors coupled to tyrosine kinase activities (agrin, integrin ligands, and reelin) and interactions with ion channels and transmitter receptors (Narp, tenascin-R and tenascin-C). These interactions may shape synaptic transmission and plasticity of excitatory synapses either via regulation of Ca2+ entry and postsynaptic expression of transmitter receptors or via control of GABAergic inhibition. The ECM molecules, derived from both neurons and glial cells and secreted into the extracellular space in an activity-dependent manner, may also shape synaptic plasticity through setting diffusion constraints for neurotransmitters...

Odontogenic ameloblast-associated protein (ODAM) has been shown to be specifically expressed in ameloblasts and odontoblasts and has been suggested to play a role in the mineralization of the enamel, possibly through the regulation of matrix metalloproteinase 20. However, its function in dentin is not clear. The purpose of this study was to evaluate the effect of ODAM on tertiary dentin formation. MDPC-23 odontoblastic cells were cultured, and the effect of recombinant ODAM (rODAM) on mineralized nodule formation was evaluated. Pinpoint pulp exposures were made in rat teeth and then capped with rODAM mixed with a carrier (rODAM group), carrier only (Carrier group), or white mineral trioxide aggregate (WMTA group). After 1, 2, and 4 weeks, odontoblasts and tertiary dentin were investigated histologically and immunohistochemically. Nodule formation in MDPC-23 cells was enhanced by rODAM treatment. Odontoblasts were polarized and showed a palisade arrangement in the remaining pulp from...

Intrauterine growth restriction (IUGR) is a significant cause of infant mortality and morbidity. It is now clear that IUGR infants exhibit higher rates of coronary heart disease, type 2-diabetes, hypertension and stroke as adults. Therefore, fetal growth not only impacts the outcome of the perinatal period, but also impacts adult well-being. The etiologies of IUGR are numerous, but are often associated with abnormalities in placental structure and function. The process of implantation and placentation requires the production of a plethora of growth factors, cell-adhesion molecules, extracellular matrix proteins, hormones and transcription factors. Many of these exhibit altered expression within the placenta of IUGR pregnancies. However, it has been difficult to fully assess their role during the development of placental insufficiency (PI) in the human, underscoring the need for animal models. Using an ovine model of PI-IUGR we have observed changes in the expression of vascular endo...