ABSTRACT
An effective method for controlling brain damage and neurodegeneration caused by inflammation remains elusive. Down-expression of the lipopolysaccharide (LPS)-induced inflammatory cytokines resulting in endotoxin tolerance is reported as an alternative anti-infection treatment. Nonetheless, because the dosage and action site are hard to control, endotoxin tolerance caused by low-dose LPS injection in brain tissue may induce side effects. The aim of this study was to test the hypothesis that static magnetic fields (SMF) stimulate endotoxin tolerance in brain tissue. In this study, survival rate and pathological changes in brain tissues of LPS-challenged mice were examined with and without SMF treatment. In addition, the effects of SMF exposure on growth rate and cytokine expression of LPS-challenged BV-2 microglia cells were monitored. Our results showed that SMF pre-exposure had positive effects on the survival rate and histological outcomes of LPS-treated mice. Furthermore, SMF exposure significantly decreased IL-6 expression in BV-2 cells (p < 0.05) by a phenomenon similar to endotoxin tolerance. We suggest that SMF has potential as an alternative simulation source for controlling LPS-induced excess neuro-inflammatory response.
Subject(s)
Brain/drug effects , Interleukin-6/metabolism , Lipopolysaccharides/toxicity , Magnetic Fields , Signal Transduction/drug effects , Animals , Brain/metabolism , Brain/pathology , Cell Proliferation/drug effects , Inflammation/chemically induced , Inflammation/metabolism , Inflammation/pathology , Interleukin-6/biosynthesis , Male , Mice , Microglia/drug effects , Microglia/pathology , Survival RateABSTRACT
OBJECTIVE: The aim of this study was to test whether Er:YAG laser-etched enamel of human teeth could act as a biologically active scaffold for tissue regeneration. BACKGROUND DATA: Hydroxylapatite (HA) with rough surface created by acid etching treatment has been used as a scaffold for tissue engineering. However, whether tooth HA can be a scaffold for osteoblastic cell seeding is still unclear. MATERIALS AND METHODS: Enamel samples from human teeth were pretreated with an Er:YAG laser to create a rough surface. Then the surface of the laser-treated enamel was examined using a surface roughness profilometer and a scanning electron microscope. In addition, static water contact angles of the Er:YAG laser-treated enamel samples were measured using goniometry. To observe the effects of cell behavior on an Er:YAG laser-roughened enamel surface, we cultured MG63 osteoblast-like cells on the surface-modified enamel samples. Alkaline phosphatase activity, a marker of cell proliferation and differentiation, was monitored and compared with that in untreated control and acid-etched enamel samples. RESULTS: Er:YAG laser treatment significantly improved the surface roughness of the enamel samples. Furthermore, MG63 osteoblast-like cells cultured on the Er:YAG laser-roughened enamel surface expressed more alkaline phosphatase activity and exhibited greater degrees of cellular differentiation than did cells that had been cultured on untreated enamel samples. CONCLUSIONS: These results demonstrate that Er:YAG laser-roughened enamel promotes osteoblastic differentiation. This finding suggests that Er:YAG laser-roughened enamel surfaces can potentially serve as a scaffold for tissue engineering.
