Curcuma longa is able to induce apoptotic cell death of pterygium-derived human keratinocytes

Copyright © 2017 Silvia Sancilio et al. Pterygium is a relatively common eye disease that can display an aggressive clinical behaviour. To evaluate the in vitro effects of Curcuma longa on human pterygium-derived keratinocytes, specimens of pterygium from 20 patients undergoing pterygium surgical excision were collected. Pterygium explants were put into culture and derived keratinocytes were treated with an alcoholic extract of 1.3% Curcuma longa in 0.001% Benzalkonium Chloride for 3, 6, and 24 h. Cultured cells were examined for CAM5.2 (anti-cytokeratin antibody) and CD140 (anti-fibroblast transmembrane glycoprotein antibody) expression between 3th and 16th passage to assess cell homogeneity. TUNEL technique and Annexin-V/PI staining in flow cytometry were used to detect keratinocyte apoptosis. We showed that Curcuma longa exerts a proapoptotic effect on pterygium-derived keratinocytes already after 3 h treatment. Moreover, after 24 h treatment, Curcuma longa induces a significant increase in TUNEL as well as Annexin-V/PI positive cells in comparison to untreated samples. Our study confirms previous observations highlighting the expression, in pterygium keratinocytes, of nuclear VEGF and gives evidence for the first time to the expression of nuclear and cytoplasmic VEGF-R1. All in all, these findings suggest that Curcuma longa could have some therapeutic potential in the treatment and prevention of human pterygium

Molecular mechanisms driving Streptococcus mitis entry into human gingival fibroblasts in presence of chitlac-nAg and saliva

The molecular mechanisms leading to Streptococcus mitis capability of entering oral cells were investigated in a co-culture of S. mitis and Human Gingival Fibroblasts (HGFs) in the presence of saliva. An innovative colloidal solution based on silver nanoparticles (Chitlac-nAg), a promising device for daily oral care, was added to the experimental system in order to study the effects of silver on the bacterial overgrowth and ability to enter non-phagocytic eukaryotic cells. The entry of bacteria into the eukaryotic cells is mediated by a signalling pathway involving FAK, integrin \u3b21, and the two cytoskeleton proteins vinculin and F-actin, and down-regulated by the presence of saliva both at 3 and 48\u2009h of culture, whereas Chitlac-n Ag exposure seems to influence, by incrementing it, the number of bacteria entering the fibroblasts only at 48\u2009h. The formation of fibrillary extrusion from HGFs and the co-localization of bacteria and silver nanoparticles within the fibroblast vacuoles were also recorded. After longer experimental times (72 and 96\u2009h), the number of S. mitis chains inside gingival cells is reduced, mainly in presence of saliva. The results suggest an escape of bacteria from fibroblasts to restore the microbial balance of the oral cavity

Preconditioning of dental alloys: Analysis of fibroblast proliferation and expression of fibronectin and chondroitin sulfate

The aim of the present study was to analyze the influence of different preconditioning treatments with either bovine serum albumin or cell culture medium of different dental metal alloys on human fibroblast cultures in the presence of such biomaterials as regards both cell proliferation rates and the expression of molecules constituting the extracellular matrix. Human fibroblasts (cell line Flow 2002) were cultured for 72 h in the presence of six single-phase dental casting alloys. The amount of Ag+ and Cu++ release into cell culture media was measured by atomic absorption spectroscopy. Incorporation of 5-bromodeoxyuridine, to investigate cell cycle, and the expression of fibronectin and chondroitin sulfate glycosaminoglycans, to evaluate cell adhesion, were analyzed with an immunocytochemical approach and related to cytocompatibility of the different substrates. The immunocytochemical analysis were performed by fluorescence microscopy and further analyzed with an image analysis software. Preconditioning treatments for 72 h induced decreasing cytotoxicity of the tested alloys: indeed metal cation concentrations decreased in cell culture media in the presence of preconditioned dental metal alloys. Both cell proliferation rates and ECM-constituting molecule expression resulted higher when tested in the presence of preconditioned dental metal alloys. Therefore, it is reasonable that preconditioning treatments of dental alloys influenced their interactions with fibroblast cultures by increasing their cytocompatibility in vitro. (c) 2005 Springer Science + Business Media, Inc

Caspase-3 is dually regulated by apoptogenic factors mitochondrial release and by SAPK/JNK metabolic pathway in leukemic cells exposed to etoposide-ionizing radiation combined treatment . 2004 May-Aug;17(2):181-90

Ionizing radiation induces a series of multiple intracellular events which can lead to activation of caspases, cytoplasmic proteases involved in the occurrence of apoptosis. The response of leukemic cells to ionizing radiation is amplified when they have been pre-treated with the anticancer drug etoposide, therefore the aim of this work has been to establish the lowest etoposide concentration combined with the lowest ionizing radiation dose to obtain the best antineoplastic response. Two leukemic cell lines, HL-60 and Jurkat, employed in this study, demonstrated different sensitivities to ionizing radiation and to etoposide treatment, with Jurkat T cells requiring a higher dose (1 μM) to display cell cycle perturbation and apoptotic DNA damage similar to those seen in HL-60. We hypothesize that this kind of response could be mediated by mitochondrial release of apoptogenic factors and by SAPK/JNK metabolic pathway activation, both leading to caspase-3 cleavage. All in all these results provide insight into the sensitivity or resistance of leukemic cells to antineoplastic agents and identify molecular targets for rational therapeutic intervention strategies. </jats:p