Terrein reduces pulpal inflammation in human dental pulp cells.

Terrein is a bioactive fungal metabolite whose anti-inflammatory properties are virtually unknown. The purpose of this study was to determine the effects of terrein on lipopolysaccharide (LPS)-induced expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in human dental pulp cells and to determine the mechanism of the observed effects. The LPS-induced expression of ICAM-1 and VCAM-1 was inhibited by terrein in both a time- and dose-dependent manner. LPS-stimulated translocation of nuclear factor kappa B (NF-kappaB) into the nucleus, which was blocked by inhibitors of amino kinase terminal (AKT, LY294002), extracellular signal regulated kinase 1/2 (ERK 1/2, PD98059), p38 (SB203580), and c-jun NH2-terminal kinase (JNK, SP600125) or terrein. In addition, these inhibitors and terrein also reduced the level of ICAM-1 and VCAM-1 expression in LPS-induced inflammation of pulp cells. Terrein suppressed NF-kappaB activation by blocking the activation of Akt. These results strongly suggest the potential role of terrein as an anti-inflammatory modulator in pulpal inflammation.

Anti-inflammatory effect of peroxisome proliferator activated receptor gamma on human dental pulp cells.

Peroxisome proliferator activated receptor gamma (PPARgamma) plays a critical role in controlling immune and inflammatory responses. However, its effect on pulpal inflammation has not been clarified. The purpose of this study was to determine the anti-inflammatory effect of PPARgamma on pulpal inflammation. Human dental pulp cells treated with lipopolysaccharide exhibited elevated levels of matrix metalloproteinase-2 (MMP-2), MMP-9, intracellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1). However, when treated with rosiglitazone (PPARgamma agonist) or adenoviral PPARgamma in same culture system, the expression of ICAM-1 and VCAM-1 was markedly inhibited along with decreased secretion of MMPs. In addition, the coadministration of GW9662 (PPARgamma antagonist) and rosiglitazone blocked the inhibition of MMP-2, MMP-9, ICAM-1, and VCAM-1. These results suggest that PPARgamma decreased the production of MMPs, ICAM-1, and VCAM-1 and might offer a possible attempt of using it as one of anti-inflammatory modulators in a pulpal inflammation.

Novel polymeric micelles of amphiphilic triblock copolymer poly (p-dioxanone-co-L-lactide)-block-poly (ethylene glycol).

PURPOSE: The objective of this study is to characterize the micelles of novel block copolymer of poly (p-Dioxanone-co-L-Lactide)-block-Poly (ethylene glycol) (PPDO/PLLA-b-PEG-) and evaluate its ability to induce gene transfection. METHODS: The ability of the block copolymer to self-assemble was determined by viscometery, dye solublization, NMR spectra and dynamic light scattering. The Trypan blue assay for in vitro biocompatibility of the block copolymer was carried out with NIH 3T3, CT-26 and MCF-7 cells, and beta-glactosidase assay was applied to measure the transfection efficiency of the block copolymer on MCF-7 breast cancer cell. RESULTS: Depending on the block lengths and molecular weights, solubility of the polymeric samples in water was varied. Diluted aqueous solution properties of the copolymer were studied. 1,6-Diphenyl-1,3,5-hexatriene solubilization and 1H NMR spectra carried out in CDCl3 and D2O, were used to prove the existence of hydrophobic domains as the core of micelle. Average particle size of 60-165 nm with low polydispersity, and lower negative zeta potential of -3 to -14 mV were observed on the aqueous copolymer dispersion. Copolymer was found with almost no cytotoxic effect and was able to promote the transfection efficiency (about 3-fold) in MCF-7 cells. CONCLUSIONS: The PPDO/PLLA-b-PEG copolymer has ability to assemble into nanoscopic structures in aqueous environment, which enable to enhance gene transfection.