The Multifarious Functions of Leukotrienes in Bone Metabolism.

Leukotrienes (LTs) are derived from arachidonic acid metabolism by the 5-lipoxygenase (5-LO) enzyme. The production of LTs is stimulated in the pathogenesis of rheumatoid arthritis (RA), osteoarthritis, and periodontitis, with a relevant contribution to bone resorption. However, its role in bone turnover, particularly the suppression of bone formation by modulating the function of osteoclasts and osteoblasts, remains unclear.

Fluoride and trimetaphosphate association as a novel approach for remineralization and antiproteolytic activity in dentin tissue.

Objective: The study evaluated the effect of solutions containing fluoride (F) and/or sodium trimetaphosphate (TMP) and F/TMP on the inhibition of MMP-2 and MMP-9, and on dentin remineralization in vitro.

Design: Bovine root dentin blocks were prepared, and caries-like lesions were induced in two thirds of the surface. Blocks were then randomly divided into 13 groups/solutions (n = 10): Placebo; 0.

Cell Surface Glycoprotein CD24 Marks Bone Marrow-Derived Human Mesenchymal Stem/Stromal Cells with Reduced Proliferative and Differentiation Capacity In Vitro.

Bone marrow-derived mesenchymal stem/stromal cells (BMSCs) are fundamental to bone regenerative therapies, tissue engineering, and postmenopausal osteoporosis. Donor variation among patients, cell heterogeneity, and unpredictable capacity for differentiation reduce effectiveness of BMSCs for regenerative cell therapies. The cell surface glycoprotein CD24 exhibits the most prominent differential expression during osteogenic versus adipogenic differentiation of human BMSCs.

Residual decontamination chemical agents negatively affect adhesion and proliferation of osteoblast-like cells on implant surface.

Purpose: To investigate the influence of implant surface decontaminated and uncontaminated on osteoblast-like cell adhesion and proliferation MATERIALS AND METHODS: Commercially available implants of different brands and surface characteristics were selected: Biomet 3i® Nanotite (NT) and Osseotite (OT), Straumann® SLActive (SLA), and Neodent® Acqua Drive (ACQ) and Neoporos Drive CM (CM). Physical and chemical properties of the implants were investigated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and wettability analysis (WETT). Implants were previously contaminated with Aggregatibacter actinomycetemcomitans strains; after that, samples were decontaminated by different chemical methods.

In vitro effect of curcumin-mediated antimicrobial photodynamic therapy on fibroblasts: viability and cell signaling for apoptosis.

Although it was demonstrated that curcumin-mediated antimicrobial photodynamic therapy (aPDT) is effective for reducing the viability of microbial cells and the vitality of oral biofilms, the cytotoxicity of this therapeutic approach for host cells has not been yet elucidated. Hence, the aim of this study was to evaluate the cytotoxicity and apoptotic effects of curcumin-mediated aPDT on mouse fibroblasts. Cells were treated with 0.

HOXA cluster gene expression during osteoblast differentiation involves epigenetic control.

The HOXA gene cluster is generally recognized as a pivotal mediator of positional identity in the skeletal system, expression of different orthologues conferring alternative locational phenotype of the vertebrate bone. Strikingly, however, the molecular mechanisms that regulate orthologue-specific expression of different HOXA cluster members in gestating osteoblasts remain largely obscure, but in analogy to the processes observed in acute lymphatic leukemia it is assumed that alternative methylation of HOXA promoter regions drives position specific expression patterns. In an effort to understand HOXA cluster gene expression in osteogenesis we characterize both expression and the epigenetic landscape of the HOXA gene cluster during in vitro osteoblast formation from mesenchymal precursors.

An extract from Myracrodruon urundeuva inhibits matrix mineralization in human osteoblasts.

Ethnopharmacological Relevance: Phytotherapy based on plant-derived compounds is an alternative medicinal strategy for the relief of symptoms and the curing of diseases. The leaves of Myracrodruon urundeuva a medicinal plant also known as "aroeira", has been used in traditional medicine as healing, antiulcer and anti-inflammatory to treat skeletal diseases in Brazil, but its role in bone cell toxicity, as well as in bone formation, remains to be established.

Aim Of The Study: We sought to determine the in vitro osteogenic effects of a hydroalcoholic M.

Low level laser therapy modulates viability, alkaline phosphatase and matrix metalloproteinase-2 activities of osteoblasts.

Low level laser therapy (LLLT) has been shown to stimulate bone cell metabolism but their impact on the matrix metalloproteinase (MMP) expression and activity is little explored. This study evaluated the influence of LLLT at two different wavelengths, red and infrared, on MC3T3-E1 preosteoblast viability, alkaline phosphatase (ALP) and MMP-2 and -9 activities. To accomplish this, MC3T3-E1 cells were irradiated with a punctual application of either red (660nm; InGaAIP active medium) or infrared (780nm; GaAlAs active medium) lasers both at a potency of 20mW, energy dose of 0.

Low intensity lasers differently induce primary human osteoblast proliferation and differentiation.

Among various compounds used in research and clinic for degenerative bone diseases, low level laser therapy (LLLT), comprising low level lasers (LLL) and light emitting diodes (LEDs), has been investigated regarding its effects on bone metabolism. They have specific wavelengths but in general act as a cellular biomodulator, and as a therapeutic agent, rebalancing and normalizing their activity. However, they are not standardized yet, since their parameters of use are relevant for the effects and mechanisms of action.

"Aroeira" (Myracrodruon urundeuva) methanol extract: the relationship between chemical compounds and cellular effects.

Context: "Aroeira" [Myracrodruon urundeuva Allemão (Anacardiaceae)] is a tree whose leaves have been studied for therapeutic purposes in medicine and dentistry.

Objective: The study chemically identifies the leaf extract of aroeira and determines its effect on human gingival fibroblasts.

Materials And Methods: An 80% methanol leave extract was obtained by maceration and chemically identified through flow-injection analysis-electrospray ionization-ion trap-tandem mass spectrometry (FIA-ESI-IT-MS).