Papers by Keyword: Cytotoxicity

Abstract: Magnetic nanoparticles have potential application in biomedicine since their features allow a wide variety of applications, such as drug carriers, destruction of tumor cells and magnetic separation of cells and proteins. Overlooking that, the proposal is to obtain the hybrid NiFe₂O₄/SiO₂ from the surface modifying with the 3-aminopropyltriethoxysilane, and evaluate the structure, morphology and cytotoxicity, to obtain a biocompatible hybrid for biological applications, such as, e.g., drug carrier. The samples were analyzed by XRD, FTIR, SEM, magnetic measurements and cytotoxicity. The results showed the formation of single phase of the NiFe₂O₄ spinel with crystallite size of 35 and 32 nm referring to the samples before and after the surface modification, and presence of characteristic absorption bands of the spinel and of the silanol group from the silane agent, confirming the hybrid formation. The presence of the silane agent kept the ferrimagnetic characteristic and increased the cell viability, making it a non-cytotoxic material.

Abstract: The unique physical properties and strength of carbon nanotube (CNT) lend to its wide application in many fields as diverse engineering, physics and biomedicine. Biomedicine, the toxicity of CNTs was cause for concern on the application as a delivery tool for therapeutic proteins, peptides and genes in the treatment of cancer and neurodegeneration. CNTs were reported to exert adverse effects on normal neuronal function, probably due accumulation in the brain, leading to brain damage. Thus, toxicity tests of CNTs on cells would be relevant in determining potential side effects and dosage. This study was set out to evaluate the toxicity of SWCNTs derived from fermented tapioca on SH-SY5Y cells. Fermented tapioca, was a well known Malaysian local food, and was an excellent precursor for SWCNT synthesis. The raw synthesized SWCNTs were directly used to study the effect on SH-SY5Y cells. Cytotoxicity and neurotoxicity test were performed. The neurotoxicity test results showed higher cell viability compared to the cytotoxicity test. Cell viability for neurotoxicity test was above 50 % for CNT concentration ranges of 250 μg/ml and below. However cell viability decreased markedly at 500 μg/ml. The percentage of cell viability was high at 50 μg/ml and below for the first 24 h of treatment but longer treatment duration resulted in significant decrease in cell viability for all concentrations above 10 μg/ml. These findings demonstrated that CNTs were safe when used at concentration less than 10 μg/ml.

Abstract: The objective of the study was to determine the degree of biocompatibility of leucite glass-ceramics that have been produced from local high grade silica sand in terms of cytotoxicity and mutagenicity assays. In the present study, the cyctotoxicity and mutagenicity were studied using the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay (MTT) and Ames Reverse Mutation. In the MTT assay, a dose response cytotoxicity of leucite sample was evaluated in L929 cells. The cells were treated with the concentrations of 6.25, 12.5, 25.0, 50.00, 100.00 and 200.00 mg/ml of the leucite sample for 24 hours. The cytotoxicity was determined by assessing the cell viability through the reduction of tetrazolium salts (MTT). The mutagenenicity of leucite sample was evaluated in S. typhirium TA98. TA100, TA1535, TA1537 and E. coli WP2 in the Ames Reverse Mutation assay. Mutagenic effects were evaluated by comparing the mean number of revertant colonies of each extract concentraction with mean number of revertant colonies of the negative control. In results of MTT assay evaluated that the leucite did not show a cytotoxic effect at all concentrations under the condition of the study. Ames Reverse Mutation assay result proven that the leucite sample did not demonstrate a mutagenic effect under the condition of this study with Salmonella typhimurium and Escherichia coli.

Abstract: The effect of manufactured nanoparticles on the expression of proinflammatory cytokine genes was examined. THP-1 cells differentiated into macrophage cells were exposed to TiO₂ and NiO medium dispersions. After 2, 6, 12, or 24 hours exposure, the expression of IL-1β, IL-6, IL-8, TNF-α and HO-1 genes was determined by real-time PCR. TiO₂ nanoparticles did not affect cytokine production. In addition, TiO₂ nanoparticles did not dissolve in the dispersion. On the other hand, NiO nanoparticles enhanced the expression of all the genes tested. NiO dispersions were composed of 58.3 μg/mL of NiO nanoparticles and 45.8 μg/mL of Ni²⁺. The release of metal ions from the nanoparticles is associated with their cytotoxicity. Therefore, the effect of an NiCl₂ solution containing 45.8 μg/mL of Ni²⁺ on the expression of cytokine genes was also examined. The effects of NiCl₂ were similar to those of the NiO nanoparticles. Furthermore, the effect of ZnO, SiO₂-coated ZnO, Sb₂O₃, and Cr₂O₃ nanoparticles on the expression of IL-1β, IL-8 and TNF-α genes was examined. Soluble nanoparticles, such as ZnO, SiO₂-coated ZnO, and Cr₂O₃ enhanced the gene expression of cytokines. Sb₂O₃ nanoparticles showed poor solubility and did not affect the expression of cytokine genes. In conclusion, these results suggest that nanoparticle solubility plays an important role in regulating the expression of proinflammatory cytokines.

Abstract: Hepatocarcinoma, a malignant cancer, threaten human life badly. It is a current issue to seek the effective natural remedy from plant to treat cancer due to the resistance of the advanced hepatocarcinoma to chemotherapy. Puerarin (Pue), a major active ingredient in the traditional Chinese medicine Gegen, has a wide range of pharmacological properties and is considered to have anti-hepatocarcinoma effects. However its low oral bioavailability restricts its wide application. In this report, Pue-nanosuspension (Pue-NS) composed of Pue and poloxamer 188 was prepared by high pressure homogenization technique. The in vitro anti-hepatocarcinoma effects of Pue-NS relative to efficacy of bulk Pue were evaluated. The particle size and zeta potential of Pue-NS were 218.5 nm and −18.8 mV, respectively. MTT assay showed that Pue-NS effectively inhibited the proliferation of HepG2 cells, and the corresponding IC₅₀ values of Pue-NS and bulk Pue were 3.39 and 5.73 μg/ml. These results suggest that the delivery of Pue-NS is a promising approach for treating tumors.

Abstract: Several tests for the biological evaluation of bioceramic materials and medical devices are provided in specific international standards, where in vitro tests have a major role. Tests involving exposure of cells in culture require the use of validated positive controls, which, in the same preparation and treatment conditions, present a substantial and well-known cytotoxicity. The present work aimed to test and validate 3 different sources of low cost, commercially available latex, as positive controls in cytotoxicity tests for bioceramic materials performed by indirect exposure. The tested origins for latex samples were: surgical gloves without powder, 100% pure amber latex hospital-grade tourniquets and 60 % latex White tubing. MC3T3-E1 murine pre-osteoblasts in culture were exposed to conditioned media (extracts) of each material tested, along with sintered stoichiometric hydroxyapatite bioceramics, and polystyrene beads as negative control. Cell viability was determined by XTT and Crystal Violet Exclusion tests. Concentration curves of the extracts were performed to obtain the DC₅₀. Only the 100% pure amber latex tubing was proven to be cytotoxic, with cell survival less than 5%. This material did not affected neighboring groups at the same experimental system. Moreover, latex samples showed great repeatability in different tests against latex and biomaterials, with consistent toxicity under 20% cell survival as shown in 3 different cell viability parameters. We conclude that fragments of latex ambar tubing are suited as effective positive controls in tests of medical bioceramic materials.

Abstract: We have previously synthesized silver-containing hydroxyapatite (Ag-HAp) powders by an ultrasonic spray-pyrolysis (USSP) technique. On the other hand, we have successfully fabricated novel calcium-phosphate cements (CPCs) composed of mainly β-tricalcium phosphate (β-TCP) phase with anti-washout property (hereafter, β-TCP cement), which was set on the basis of chelate-bonding ability of inositol phosphate (IP6). In this study, we developed novel CPCs with both anti-bacterial and anti-washout properties by adding the Ag-HAp powder into the above β-TCP cements, and examined their anti-bacterial property and cytotoxicity. The Ag-HAp powders with Ag contents of 0, 2, and 5 mol% as a nominal composition were synthesized by an USSP technique. The raw powder for β-TCP cement was prepared by ball-milling the commercially-available β-TCP powder in the IP6 solution. The Ag-HAp/β-TCP powders were prepared by mixing Ag-HAp powder and β-TCP cement powder at a ratio of 25:75 in mass. The Ag-HAp/β-TCP cement was fabricated by mixing the above-mentioned Ag-HAp/β-TCP powder and 2.5 mass% Na₂HPO₄ solution at a powder/liquid ratio of 1/0.3 [g/cm³]. The anti-bacterial property of resulting cements was evaluated using Staphylococcus aureus by biofilm formation test. The Ag-HAp/β-TCP cements containing 2 and 5 mol% Ag showed strong anti-bacterial property among examined specimens. Furthermore, the cytotoxicity of Ag⁺ ion eluted from these cements was also examined using osteoblastic MC3T3-E1 cells and Transwell^® kit. The relative cell viability cultured on each Ag-containing cement specimen was over 80 %, compared with the control (polystyrene plate). These results demonstrate that the present Ag-HAp/β-TCP cements containing 2 mol% Ag are promising one of the candidates as CPCs with both anti-bacterial property and biocompatibility.

Abstract: BEL-7402, HT-29, SPC-A1, U-251 bioassay-guided fractionation led to the isolation of the three active constituents from a wild fungi, Boletus edulis Bull. Ex Fr., which collected from Changbai Montain area. These three compounds’ chemical structures were elucidated on the base of spectroscopic data and comparison with known compounds as 5-cholestene-2,3-oxide (1), β-sitosterol (2), stigmasterol (3). All of the three compounds were extracted from Boletus edulis for the first time, and compound 1 was significantly cytotoxic against the four human cancer cell lines (BEL-7402, HT-29, SPC-A1 and U-251) with IC50 values 6.29, 6.98, 4.79 and 7.54 μM, respectively. Results of the study could supply referencs to the people to find the new drug from the fungus.

Abstract: Objective: To investigate the effects of TGFα-SAP on the inhibition of neointimal hyperplasia of rat which suffered from common carotid arterial injury. Methods: Saporin and TGFα were conjugated by using N-succinimidyl-3 (2-pyridyldithio) propionate. seventy rats were divided into two groups at random, the TGFα-SAP treated group was treated with local injection of TGFα-SAP (5μg/kg) after injury, and the control group was treated with saline. PCNA analysis and TUNEL analysis were performed. Results: Compared to the control group, the TGFα-SAP treated group showed a significant inhibition of intimal thickness and exhibited a lower P/A ratio and a higher rate of apoptosis. Conclusion: TGFα-SAP, as a potential stent coating material, could inhibit neointimal hyperplasia by inhibiting the proliferation and promoting the apoptosis of smooth muscle cells in the neointima.

Abstract: Hepatocarcinoma, a malignant cancer, threaten human life badly. It is a current issue to seek the effective natural remedy from plant to treat cancer due to the resistence of the advanced hepatocarcinoma to chemotherapy. Curcumol (Cur), a novel compound extracted from rhizoma curcumae, exhibits various anticancer activities and can be treat hepatocarcinoma. However, the low solubility hinders development. We evaluate both the in vitro and in vivo antitumor activity of Cur-nanosuspension (Cur-N) relative to efficacy of bulk Cur. Cur-N with a particle size of 231.2 ± 7.2 nm and a zeta potential of −27.3 ± 0.6 mV, prepared by the high-pressure homogenization (HPH) technique. CCK-8 assay showed that Cur-N effectively inhibited the proliferation of H22 cells. In vivo studies also showed higher antitumor efficacy against H22 solid tumor bearing mice. These results suggest that the delivery of Cur-N is a promising approach for treating tumors.