Cytotoxic Effects of Bulk-Fill Composites on L929 Fibroblast Cells

Objective: Unlike traditional composite resins, bulk-fill composite resins could be polymerized as thicker layers. This study aims to contribute to the field by investigating the cytotoxic effects of various bulk-fill composite resins on L929 mouse fibroblast cells in vitro. Material and Methods: In our study, six bulk fill and one conventional composite resin were used. Composite resin samples (8×4 mm) were prepared in a sterile cabinet by using a glass mod and polymerizing with a led light device (DTE LUX E, Germany). Composite samples (n:3) of which surface area was calculated according to ISO 10993-12: 2012 standards (3 cm2/ml), were kept in media for 24 h and 72 h in 37 oC incubator, their extracts were filtered in 1:1 and 1:2 proportion and were added on L929 mouse fibroblast cells. Cell viability was examined by the MTT assay and cell death by the LDH test. Cell viability results were evaluated using one-way analysis of variance (ANOVA) test (p<0.05). Results: When the 1:1 extracts from 4 mm thick bulk-fill composite samples were applied on L929 mouse fibroblast cells, cell viability rates showed significant differences compared to the control group at the end of 24 h and 72 h (except for Estelite Bulk Fill Flow). Although the extracts of the tested composite samples at 1:1 and 1:2 ratio at the end of 72 hours caused a decrease in L929 mouse fibroblast cell viability, the cell viability rate of only PRG-containing bulk fill composite and conventional composite remained below the cell viability ratio (70%) specified in ISO standards. Bulk fill composites did not produce toxic effects (except Beautifil Bulk Restorative) according to the LDH test. Conclusions: Despite decreasing in general the cell viability, bulk-fill composite resins used in 4 mm thick layers provided cell viability rates over the acceptability level, except PRG-containing bulk fill composite (Beautifil Bulk Restorative), which was cytotoxic to L929 mouse fibroblasts. Keywords Bulk fill composite; Cytotoxicity; L929 cells; LDH assay.

TMEM165 a new player in proteoglycan synthesis: loss of TMEM165 impairs elongation of chondroitin- and heparan-sulfate glycosaminoglycan chains of proteoglycans and triggers early chondrocyte differentiation and hypertrophy

TMEM165 deficiency leads to skeletal disorder characterized by major skeletal dysplasia and pronounced dwarfism. However, the molecular mechanisms involved have not been fully understood. Here, we uncover that TMEM165 deficiency impairs the synthesis of proteoglycans by producing a blockage in the elongation of chondroitin-and heparan-sulfate glycosaminoglycan chains leading to the synthesis of proteoglycans with shorter glycosaminoglycan chains. We demonstrated that the blockage in elongation of glycosaminoglycan chains is not due to defect in the Golgi elongating enzymes but rather to availability of the co-factor Mn2+. Supplementation of cell with Mn2+ rescue the elongation process, confirming a role of TMEM165 in Mn2+ Golgi homeostasis. Additionally, we showed that TMEM165 deficiency functionally impairs TGFβ and BMP signaling pathways in chondrocytes and in fibroblast cells of TMEM165 deficient patients. Finally, we found that loss of TMEM165 impairs chondrogenic differentiation by accelerating the timing of Ihh expression and promoting early chondrocyte maturation and hypertrophy. Collectively, our results indicate that TMEM165 plays an important role in proteoglycan synthesis and underline the critical role of glycosaminoglycan chains structure in the regulation of chondrogenesis. Our data also suggest that Mn2+ supplementation may be a promising therapeutic strategy in the treatment of TMEM165 deficient patients.

Study of Caffeine-Loaded Gelatin Nanoparticles for Treatment of Melanoma and Fibroblast Cells

In this work, we aimed to study the effect of caffeine-loaded gelatin nanoparticles on melanoma cells and fibroblast cells. The B16F10 murine melanoma cells and L929 fibroblast cells were treated with a different dilution ratio of caffeine-loaded gelatin nanoparticles for 24, 48, and 72 h. The cell assay results showed that treatment with caffeine-loaded gelatin nanoparticles (25 % and 50 %) effectively inhibited the proliferation, viability, and migration ability of B16F10 melanoma cells at 48 and 72 h. Moreover, we also found that the cell apoptosis of B16F10 melanoma cells was induced by treatment of 12.5, 25, and 50 % caffeine-loaded gelatin nanoparticles. In the meantime, for L929 fibroblast cells, there was no significant cell cytotoxic effects observed with identical treatment. In summary, the caffeine-loaded gelatin nanoparticles induced apoptotic process inhibited cell viability and migration ability of melanoma cells and could be an alternative therapy for melanoma cancer.

Isolating and growing fibroblast cells from threespine stickleback (Gasterosteus aculeatus) v2

This protocol goes through the process of isolating and growing fibroblast cells from threespine stickleback.

Annealing Temperature Influences the Cytocompatibility, Bactericidal and Bioactive Properties of Green Synthesised TiO2 Nanocomposites from Calotropis Gigantea

Annealing is a crucial functional parameter relevant to the green synthesis and bactericidal properties of TiO2 nanocomposites (TiO2-NPs). In this work, the effect of the annealing temperature on the physicochemical and bactericidal properties of TiO2-NPs obtained from Calotropis gigantea was comprehensively studied. The synthesised TiO2-NPs were characterised using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, UV–Vis spectrophotometer and FTIR spectroscopy. The bactericidal properties were determined via the minimum inhibitory concentration (MIC) and Kirby–Bauer disc diffusion methods. The cytocompatibility of green TiO2 was further investigated using fibroblast cells lines model. Results indicated that amorphous-phase TiO2-NPs were transformed into the anatase phase at 500 °C with a crystallite size of 40.9 nm and MIC of 100 mg/mL towards S. aureus (colony count reduction from 4.3 log10 to 1.01 log10). Whereas TiO2-NPs annealed at 400 °C demonstrated no bacterial reduction, TiO2-NPs annealed at 500 °C showed a moderate zone of inhibition of 6.33–6.83 mm towards Escherichia coli and Pseudomonas aeruginosa. Findings from this study found that TiO-500C nanocomposites concentration at 100 mg/mL is cytocompatible to the fibroblast cells lines with proliferation rate/activity higher than 116% after 24 h treatment. The plant-mediated nano-sized cubic and spherical anatase TiO2-NPs encapsulated bioactive green elements, such as carbon, sodium, magnesium, chlorine, potassium, calcium and sulphur, from the C. gigantea extract, ultimately leading to versatile and eco-friendly bactericidal agents with wound-healing properties. Further studies are necessary to support the findings of this work.