The effect of histone deacetylase inhibitor Trichostatin A on IL-17A-induced transformation of MRC5 into myofibroblasts and its mechanism

Objective To elucidate potential IL-17A- and TSA-mediated regulation of fibroblasts transformation. Methods MTT assay, HDAC1 activity assay, cell immunofluorescence and Western blot were employed to detect the expression of related indicators. Results MRC5 cells expressed only a small amount of Vimentin. IL-17A treatment upregulated MRC5 cell proliferation, in a concentration-dependent manner. TSA treatment, however, suppressed MRC5 cell proliferation. IL-17A treatment also upregulated HDAC1 activity in MRC5 cells, in a concentration-dependent manner. Using immunofluorescence, we demonstrated that IL-17A-treated MRC5 cells had markedly elevated Vimentin, Collagen-I and a-SMA levels, compared to controls. However, a combined treatment of IL-17A and TSA resulted in markedly reduced levels of the Vimentin, Collagen-I and a-SMA, compared to IL-17A alone, yet the amount was higher than controls. Using western blot analysis, we also revealed that the IL-17A-treated MRC5 cells had markedly elevated levels of Vimentin, a-SMA, HDAC1, p-Smad2, and p-Smad3, and markedly reduced level of Smad7, compared to controls. In TSA intervention group, the expression effect of the above protein was opposite. Moreover, no discernible difference was observed in the levels of Smad2 and Smad3 among the treated and un-treated groups. Conclusion IL-17A stimulates proliferation of MRC5 cells and increases HDAC1 activity and protein expression. It also transforms MRC5 cells into myofibroblasts via activation of the TGF -β1/ Smads signaling network. TSA, on the other hand, strongly suppresses TGF -β1/ Smads pathway-mediated fibrosis by ceasing HDAC1 activity and protein expression.

Design and Synthesis of 4-O-Podophyllotoxin Sulfamate Derivatives as Potential Cytotoxic Agents

4-O-Podophyllotoxin sulfamate derivatives were prepared using the natural lignan podophyllotoxin. The prepared compounds were afforded by reacting O-sulfonyl chloride podophyllotoxin with ammonia or aminoaryl/heteroaryl motif. Biological evaluation was performed in human breast cancer (MCF7), ovarian cancer (A2780), colon adenocarcinoma (HT29), and normal lung fibroblast (MRC5) cell lines. Compound 3 exhibited potent inhibitory activity and good selectivity margin. Compounds 2, 3, and 7 exerted apoptotic effect in MCF7 cells in a dose-dependent manner. The cytotoxicity of the verified compounds was inferior to that of podophyllotoxin.

Modulus, Strength and Cytotoxicity of PMMA-Silica Nanocomposites

Key advantages of Poly(methyl methacrylate)—PMMA for denture application are related to aesthetics and biocompatibility, while its main deficiency is related to mechanical properties. To address this issue, SiO2 nanoparticle reinforcement was proposed, containing 0 to 5% nanosilica, to form nanocomposite materials. Flexural strengths and elastic moduli were determined and correlated to nominal nanoparticle content and zeta potential of the liquid phase nanoparticle solutions. Another issue is the biocompatibility, which was determined in terms of cytotoxicity, using L929 and MRC5 cell lines. The addition of nanoparticle was proved to be beneficial for increasing flexural strength and modulus, causing a significant increase in both strength and moduli. On the other hand, the formation of agglomerates was noted, particularly at higher nanoparticle loadings, affecting mechanical properties. The addition of nanosilica had an adverse effect on the cytotoxicity, increasing it above the level present in unmodified specimens. Cytotoxic potential was on the acceptable level for specimens with up to 2% nanosilica. Consequently, nanosilica proved to be an effective and biocompatible means of increasing the resistance of dental materials.

Enhanced β-Catenin/Foxo1 Activity Alleviates Pulmonary Fibrosis by Inhibiting β-Catenin/T Cell Factor Signaling

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive fibrosing interstitial pneumonia, resulting in chronic respiratoryfailure and eventually death. β-catenin/Foxo1 showed a protective property in kidney fibrosis, but the role of β-catenin/Foxo1 in IPF was unclear. Our study aimed to investigate the role of β-catenin/Foxo1 in IPF and explore its underlying mechanism. The IPF model was established by injection of bleomycin (BLM) in vivo and stimulation by TGF-β1 in MRC5 cell in vitro. Haematoxylin-eosin staining and Masson’s trichrome staining were performed to examine histopathological injury in lung. Protein expression of corresponding genes was detected using western blot. Immunofluorescence staining assay was carried out to detect the expression of β-catenin, Foxo1, TCF and α-SMA. The expression levels of inflammatory cytokines were determined using ELISA kit assay. The results showed that BLM induced a serious pulmonary injury and proliferated fibroblasts. A higher interaction of β-catenin with TCF and a lower interaction of β-catenin with Foxo1 was found in BLM group compared to the control group. TGF-β1 promoted β-catenin/TCF, whereas ICG-001 inhibited β-catenin/TCF, and promoted β-catenin/Foxo1. Furthermore, ICG-001 reversed TGF-β1 induced largely production of inflammatory cytokines and accumulation of extracellular matrix, as well as high expression of α-SMA. However, AS1842856, a FOXO1 antagonist, strengthened the effects induced by TGF-β1. In summary, our study revealed that β-catenin/Foxo1 protected against IPF through inhibiting inflammatory response and extracellular matrix accumulation, providing an alternative approach to explain the potential mechanism of IPF and seek for more effective therapeutic drugs.

Cytotoxicity of Dental Adhesives In Vitro

ABSTRACTObjectives: The purpose of this study was to evaluate the cytotoxic effect of six dental adhesives (Admira Bond, Clearfil Liner Bond 2V, ED Primer II, Fuji Bond LC, Gluma Comfort Bond, and NanoBond) applied to cell cultures.Methods: The experiments were performed on two cell lines, rat pulp cells (RPC-C2A) and human lung fibroblasts (MRC5). Samples of the adhesives were light-cured and placed in culture medium for 24 hours. The extraction media was applied on the RPC-C2A and the MRC5 cells. Complete medium was used as a control. Cytotoxicity was evaluated with a modified sulforhodamine B (SRB) assay after 24 hours of exposure.Results: The cell survival of RPC-C2A cells exposed to Fuji Bond LC, NanoBond, Clearfil Liner Bond 2V, ED Primer II, Admira Bond and Gluma Comfort Bond was 73%, 67%, 50%, 20%, 18% and 5% respectively, relative to the cell survival with the control medium. In the MRC5 cell line, the relative survival was 98%, 80%, 72%, 41%, 19% and 7% after exposure to NanoBond, Fuji Bond LC, Clearfil Liner Bond 2V, ED Primer II, Admira Bond and Gluma Comfort Bond, respectively.Conclusions: Different types of dental adhesives showed different cytotoxic effects on cells in vitro. The self-etch adhesives were superior in terms of cytotoxicity. The different cytotoxic effects of dental adhesives should be considered when selecting an appropriate adhesive for operative restorations. (Eur J Dent 2009;3:3-9)