Cartilage oligomeric matrix protein (COMP) is a potential biomarker for joint destruction associated with osteoarthritis, which is first and best investigated biomarkers to reflect osteoarthritis occurs, progress and the prognosis. In this article, multiple uses and related reports of COMP are summarized briefly to promote further investigation of COMP.
Biomarkers ; blood ; Cartilage Oligomeric Matrix Protein ; Extracellular Matrix Proteins ; blood ; chemistry ; metabolism ; Glycoproteins ; blood ; chemistry ; metabolism ; Humans ; Matrilin Proteins ; Osteoarthritis ; blood ; diagnosis ; Prognosis

Pathogenicity of Treponema pallidum may depend upon the binding of Treponema pallidum to matrix proteins, especially to fibronectin. Infectious organism or cell to matrix interactions are mediated by a family of adhesion molecule receptors known as integrins. Once in the host, the pathogenic Treponema pallidumdum adheres to the vascular endothelium and readily penetrates surrounding tissues. Fibronectin plays an important role in the mediation of the attachment of Treponema pallidum to host cells, including endothelial cells. We found that the binding of Treponema pallidum to human dermal microvascular endothelial cells and to a glass surface coated with fibronectin is inhibited by the presence of arginine-glycine- aspartic acid (RGD), and analysis of the surface receptor revealed an antigenic similarity to an integrin molecule, namely alpha5. This ability to adhere to host endothelium and fibronectin is quite unique to T. pallidum among the treponemes, and may be a key pathogenic factor.
Carrier Proteins/*physiology ; Cell Membrane/metabolism ; Cells, Cultured ; Endothelium, Vascular/cytology/*metabolism ; Extracellular Matrix Proteins/*metabolism ; Human ; Microcirculation ; Skin/*blood supply ; Support, Non-U.S. Gov't ; Treponema pallidum/*physiology

The blood-brain barrier (BBB) is a tight boundary formed between endothelial cells and astrocytes, which separates and protects brain from most pathogens as well as neural toxins in circulation. However, detailed molecular players involved in formation of BBB are not completely known. Dentin matrix protein 1 (DMP1)-proteoglycan (PG), which is known to be involved in mineralization of bones and dentin, is also expressed in soft tissues including brain with unknown functions. In the present study, we reported that DMP1-PG was expressed in brain astrocytes and enriched in BBB units. The only glycosylation site of DMP1 is serine89 (S89) in the N-terminal domain of the protein in mouse. Mutant mice with DMP1 point mutations changing S89 to glycine (S89G), which completely eradicated glycosylation of the protein, demonstrated severe BBB disruption. Another breed of DMP1 mutant mice, which lacked the C-terminal domain of DMP1, manifested normal BBB function. The polarity of S89G-DMP1 astrocytes was disrupted and cell-cell adhesion was loosened. Through a battery of analyses, we found that DMP1 glycosylation was critically required for astrocyte maturation both in vitro and in vivo. S89G-DMP1 mutant astrocytes failed to express aquaporin 4 and had reduced laminin and ZO1 expression, which resulted in disruption of BBB. Interestingly, overexpression of wild-type DMP1-PG in mouse brain driven by the nestin promoter elevated laminin and ZO1 expression beyond wild type levels and could effectively resisted intravenous mannitol-induced BBB reversible opening. Taken together, our study not only revealed a novel element, i.e., DMP1-PG, that regulated BBB formation, but also assigned a new function to DMP1-PG.
Animals ; Astrocytes ; cytology ; metabolism ; Blood-Brain Barrier ; cytology ; metabolism ; Cells, Cultured ; Extracellular Matrix Proteins ; genetics ; metabolism ; Female ; Glycosylation ; Male ; Mice ; Proteoglycans ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction

BACKGROUND: Estrogens act on estrogen receptors distributed in articular cartilages, synovial membrane, and ligaments, which are thought to be related with degenerative changes. Meanwhile, progesterone is known to have a weak anabolic action on bone formation This study evaluates the effects of estrogen and progesterone hormone on bone/cartilage turnover in ovariectomized (OVX) rats. METHODS: Thirty-five 7-month-old female Sprague-Dawley rats were randomly divided into 5 groups and then ovariectomized bilaterally except the sham control group. The first and the second group acting as controls did not receive hormonal therapy, the third group received estrogen, the fourth group received progesterone, and the fifth group received combination of both hormones 10 weeks after surgery. Evaluations were done using the serum levels of cartilage oligomeric matrix protein (COMP) for cartilage turnover, collagen type I C-telopeptide (CTX-1) and osteocalcin (OC) for bone turnover at 11, 15, 19 weeks after OVX and histology using the Osteoarthritis Research Society International (OARSI) osteoarthritis (OA) cartilage histopathology assessment system. RESULTS: Significantly less cartilage degradation (decreased levels of COMP) was found in the combined hormone treated group in comparison with OVX group. Similarly, both hormonal treatment resulted in increased bone formation and decreased bone resorption i.e., a low overall bone turnover status (decrease in the serum OC and CTX-1 levels). CONCLUSIONS: Combined estrogen and progesterone therapy was found to be convincing in terms of reducing the severity of OA in this experimental model.
Animals ; Biological Markers/blood/metabolism ; Bone Remodeling/*drug effects ; Bone and Bones/chemistry/drug effects ; Cartilage/chemistry/*drug effects ; Collagen Type I/blood/metabolism ; Disease Models, Animal ; Estrogens/*pharmacology ; Extracellular Matrix Proteins/blood/metabolism ; Female ; Glycoproteins/blood/metabolism ; Histocytochemistry ; Hormone Replacement Therapy/*methods ; Osteoarthritis/blood/*drug therapy ; Osteocalcin/blood/metabolism ; Ovariectomy ; Progesterone/*pharmacology ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo study the protective effects of curcumin on exaggerated extracellular matrix accumulation of pulmonary fibrosis rats.

METHODOne hundred and forty-four male Sprague-Dawley rats were randomly divided into 6 groups (24 rats in each group). Rats in the model control group, positive medicine group, and high, moderate and low curcumin groups were injected with a single dose of bleomycin by trachea, and rats in sham-model control group with same volume normal saline. One day after the injection, curcumin solution of different dosages (200, 100, 50 mg x kg(-1) x d(-1)) was respectively given to rats in the high, moderate and low curcumin group daily by gastrogavage, while equal volume of normal saline was given to those in the sham-model control group and model control group, and an equal volume of prednisone (0.56 mg x kg(-1) x d(-1)) was given to those in positive medicine control group. On the 7, 14, 28 days, 8 rats per treatment group were randomly killed, the levels of III-collagen, IV-collagen, laminin and hyaluronic acid in the serum were determined, the determination of hydroxyproline in lung homogenates was analyzed, and the lung was incised to make pathological sections which were stained with HE and Mallory.

RESULTCurcumin could decreas the levels of III-collagen, IV-collagen, laminin and hyaluronic acid in the serum, and inhihit the proliferation of fibrous tissue.

CONCLUSIONCurcumin may play its therapetuic role by leveling down the content of extracellular matrix in rats with pulmonary fibrosis induced by bleomycin.

Animals ; Bleomycin ; Body Weight ; drug effects ; Collagen Type III ; blood ; Collagen Type IV ; blood ; Curcuma ; chemistry ; Curcumin ; isolation & purification ; pharmacology ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Extracellular Matrix Proteins ; blood ; metabolism ; Hyaluronic Acid ; blood ; Hydroxyproline ; blood ; metabolism ; Laminin ; blood ; Lung ; metabolism ; pathology ; Male ; Plants, Medicinal ; chemistry ; Protective Agents ; pharmacology ; Pulmonary Fibrosis ; chemically induced ; metabolism ; pathology ; Random Allocation ; Rats ; Rats, Sprague-Dawley