Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 28
Filter
Add more filters










Publication year range
1.
J Biol Inorg Chem ; 27(3): 329-343, 2022 04.
Article in English | MEDLINE | ID: mdl-35247094

ABSTRACT

Two ternary copper(II) complexes with 2,2'-biquinoline (BQ) and with sulfonamides: sulfamethazine (SMT) or sulfaquinoxaline (SDQ) whose formulae are Cu(SMT)(BQ)Cl and Cu(SDQ)(BQ)Cl·CH3OH, in what follows SMTCu and SDQCu, respectively, induced oxidative stress by increasing ROS level from 1.0 µM and the reduction potential of the couple GSSG/GSH2. The co-treatment with L-buthionine sulfoximine (BSO), which inhibits the production of GSH, enhanced the effect of copper complexes on tumor cell viability and on oxidative damage. Both complexes generated DNA strand breaks given by-at least partially-the oxidation of pyrimidine bases, which caused the arrest of the cell cycle in the G2/M phase. These phenomena triggered processes of apoptosis proven by activation of caspase 3 and externalization of phosphatidylserine and loss of cell integrity from 1.0 µM. The combination with BSO induced a marked increase in the apoptotic population. On the other hand, an improved cell proliferation effect was observed when combining SDQCu with a radiation dose of 2 Gy from 1.0 µM or with 6 Gy from 1.5 µM. Finally, studies in multicellular spheroids demonstrated that even though copper(II) complexes did not inhibit cell invasion in collagen gels up to 48 h of treatment at the higher concentrations, multicellular resistance outperformed several drugs currently used in cancer treatment. Overall, our results reveal an antitumor effect of both complexes in monolayer and multicellular spheroids and an improvement with the addition of BSO. However, only SDQCu was the best adjuvant of ionizing radiation treatment.


Subject(s)
Copper , Lung Neoplasms , Apoptosis , Buthionine Sulfoximine/pharmacology , Copper/chemistry , Copper/pharmacology , Glutathione/metabolism , Humans , Lung , Lung Neoplasms/drug therapy , Quinolines , Radiation, Ionizing , Sulfonamides/pharmacology
2.
Appl Opt ; 61(31): 9256-9261, 2022 Nov 01.
Article in English | MEDLINE | ID: mdl-36607061

ABSTRACT

We demonstrate that a middle sized ring laser gyroscope (RLG) can be a very sensitive and robust instrument for rotational seismology, even if it operates in a quite noisy environment. The RLG has a square cavity, 1.60×1.60m 2, and it lies in a plane orthogonal to the Earth's rotational axis. The Fabry-Perot optical cavities along the diagonals of the square were accessed, and their lengths were locked to a reference laser. Through a quite simple locking circuit, we were able to keep the sensor fully operative for 14 days. We verified that the prototype properties are compatible with the seismic requirements. The obtained long term stability is of the order of 3 nanorad/s, and the short term sensitivity is close to 2n a n o r a d/s⋅H z -1/2. These results are limited only by the noisy environment; our laboratory is located in a building downtown.

3.
Toxicol Res (Camb) ; 10(2): 192-202, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33884170

ABSTRACT

The cytotoxicity and DNA damage of titanium dioxide and zinc oxide nanoparticles (TiO2 and ZnO NPs) have been studied in a human lung carcinoma cell line (A549) after 24 h exposure. TiO2 and ZnO NPs had mean diameters of 12.9 ± 2.8 and 24.1 ± 8.0 nm, respectively. ZnO NPs reduced cell viability from 250 µg/mL, increasing reactive oxygen species (ROS) and decreased GSH/GSSG ratio. The comet assay detected DNA damage from 50 µg/mL. TiO2 NPs induced cytotoxicity and DNA damage from 50 to 100 µg/mL, respectively, along with a decrease of the GSH/GSSG ratio. Both particles were found inside the cells, within membrane-bound vesicles. The internalization mechanism is promoted partially by caveolae-mediated endocytosis and, in the case of TiO2 NPs, also by macropinocytosis.

4.
Nat Commun ; 10(1): 4981, 2019 10 31.
Article in English | MEDLINE | ID: mdl-31672992

ABSTRACT

Soil nitrogen mineralisation (Nmin), the conversion of organic into inorganic N, is important for productivity and nutrient cycling. The balance between mineralisation and immobilisation (net Nmin) varies with soil properties and climate. However, because most global-scale assessments of net Nmin are laboratory-based, its regulation under field-conditions and implications for real-world soil functioning remain uncertain. Here, we explore the drivers of realised (field) and potential (laboratory) soil net Nmin across 30 grasslands worldwide. We find that realised Nmin is largely explained by temperature of the wettest quarter, microbial biomass, clay content and bulk density. Potential Nmin only weakly correlates with realised Nmin, but contributes to explain realised net Nmin when combined with soil and climatic variables. We provide novel insights of global realised soil net Nmin and show that potential soil net Nmin data available in the literature could be parameterised with soil and climate data to better predict realised Nmin.

5.
J Biol Inorg Chem ; 24(2): 271-285, 2019 03.
Article in English | MEDLINE | ID: mdl-30701359

ABSTRACT

The aim of this work was to study the antitumor effects and the mechanisms of toxic action of a series of 6-methoxyquinoline (6MQ) complexes in vitro. The Cu(II) and Zn(II) complexes (Cu6MQ and Zn6MQ) are formulated as M(6MQ)2Cl2; the Co(II) and Ag(I) compounds (Co6MQ and Ag6MQ) are ionic with formulae [Ag(6MQ)2]+NO3- and H(6MQ)+[Co(6MQ)Cl3]- (where H(6MQ)+ is the protonated ligand). We found that the copper complex, outperformed the Co(II), Zn(II) and Ag(I) complexes with a lower IC50 (57.9 µM) in A549 cells exposed for 24 h. Cu6MQ decreased cell proliferation and induced oxidative stress detected with H2DCFDA at 40 µM, which reduces GSH/GSSG ratio. This redox imbalance induced oxidative DNA damage revealed by the Micronucleus test and the Comet assay, which turned into a cell cycle arrest at G2/M phase and induced apoptosis. In multicellular spheroids, the IC50 values tripled the monolayer model (187.3 µM for 24 h). At this concentration, the proportion of live/dead cells diminished, and the spheroids could not proliferate or invade. Although Zn6MQ also decreased GSH/GSSG ratio from 200 µM and the cytotoxicity is related to oxidative stress, the induction of the hydrogen peroxide levels only doubled the control value. Zn6MQ induced S phase arrest, which relates with the increased micronucleus frequency and with the induction of necrosis. Finally, our results reveal a synergistic activity with a 1:1 ratio of both complexes in the monolayer and multicellular spheroids.


Subject(s)
Antineoplastic Agents/pharmacology , Coordination Complexes/pharmacology , Quinolines/pharmacology , Spheroids, Cellular/drug effects , A549 Cells , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Cell Survival/drug effects , Cells, Cultured , Coordination Complexes/chemical synthesis , Coordination Complexes/chemistry , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Oxidative Stress/drug effects , Quinolines/chemistry , Spheroids, Cellular/pathology , Structure-Activity Relationship
6.
Appl Opt ; 57(28): 8373, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-30461791

ABSTRACT

This publisher's note identifies a figure error in Appl. Opt.57, 5844 (2018)APOPAI0003-693510.1364/AO.57.005844.

7.
Appl Opt ; 57(20): 5844-5851, 2018 Jul 10.
Article in English | MEDLINE | ID: mdl-30118056

ABSTRACT

Gyroscopes IN GEneral Relativity (GINGER) is a proposed experiment with the aim of measuring in a ground laboratory the gravitoelectric and gravitomagnetic effects foreseen by general relativity through an array of ring laser gyroscopes. GINGERINO is a square ring-laser prototype that has been built to investigate the level of noise inside the Gran Sasso underground laboratory. GINGERINO has shown the advantage of the underground location. Now it provides suitable data for geophysics and seismology. Since May 2017, it has continuously acquired data. The analysis of the first 90 days shows that the duty cycle is higher than 95%, and the quantum shot noise limit is of the order of 10-10(rad/s)/Hz. It is located in a seismically active area, and it recorded part of the central Italy earthquakes. Its high sensitivity in the frequency band of fraction of hertz makes it suitable for seismology studies. The main purpose of the present analysis is to investigate the long-term response of the apparatus. Simple and fast routines to suppress the disturbances coming from the laser have been developed. The Allan deviation of the raw data reaches some 10-6 after about 106 s of integration time, while the processed data show an improvement of 1 order of magnitude. Disturbances at the daily time scale are present in the processed data, and the expected signal induced by polar motion and solid Earth tides is covered by those disturbances.

8.
Minerva Gastroenterol Dietol ; 61(1): 1-9, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25288202

ABSTRACT

AIM: Esophagogastroduodenoscopy (EGDS) cannot identify microscopic lesions. We determined the contribution of real-time gastric juice analysis in detecting lesions non-detectable with the simple endoscopic inspection. METHODS: Endoscopy, histology and gastric juice analysis were performed in 216 patients. We assessed six diagnostic strategies: EGDS (strategy-1), EGDS with antral biopsies (hematoxylin-eosin staining) in hypochlorhydrics (strategy-2) or all patients (strategy-3), EGDS with antral and fundic biopsies (hematoxylin-eosin staining) in hypochlorhydrics (strategy-4) or all patients (strategy-5), EGDS with antral and fundic biopsies (hematoxylin-eosin + immunohistochemical staining) in hypochlorhydrics (strategy-6). Then, we determined how many of the pathological conditions identified by the complete histological evaluation would have been detected by each strategy. RESULTS: In total, 220 pathological conditions were identified. Hypochlorhydria was correlated (r=0.67; P<0.01) with histological lesions (85% lesions were detected in hypochlorhydrics) and high ammonium levels, with H.pylori infection (r=0.69; P<0.01). Strategy-1 identified only 5% conditions, while strategies 3 and 5 detected 68.6% and 83.2% conditions, respectively. Strategies 2, 4 and 6 (based on gastric juice analysis) yielded detection rates (61.4%, 75.5%, 90.9%) similar to or better than those of strategies 3 and 5. CONCLUSION: Real-time gastric juice analysis provided information about the presence of gastric lesions in an otherwise "normal" stomach at EGDS. It improved the diagnostic yield and optimized resource utilization without any additional effort by the endoscopist.


Subject(s)
Biopsy , Gastric Juice/chemistry , Gastric Mucosa/pathology , Gastroscopy , Helicobacter Infections/diagnosis , Helicobacter pylori/isolation & purification , Adult , Endoscopy, Digestive System/methods , Female , Gastric Acid/chemistry , Helicobacter Infections/metabolism , Helicobacter Infections/pathology , Humans , Hydrogen-Ion Concentration , Male , Middle Aged , Outpatients , Predictive Value of Tests , Prospective Studies , Reproducibility of Results , Retrospective Studies , Sensitivity and Specificity
9.
Article in English | MEDLINE | ID: mdl-25344169

ABSTRACT

The cytotoxicity and genotoxicity of novel colloidal silica spheres coated with crystalline or amorphous zirconia (SiO2@ZrO2(cryst) or SiO2@ZrO2(am)) have been studied in a human osteosarcoma cell line (MG-63), after 24 h exposure. SiO2@ZrO2(cryst) and SiO2@ZrO2(am) had mean diameters of 782±19 and 891±34 nm, respectively. SiO2@ZrO2(cryst) exposure reduced cell viability, with an increase in reactive oxygen species (ROS) and a decrease of the GSH/GSSG ratio. The comet and micronucleus (MN) assays detected DNA damage at 5 and 25 µg/mL, respectively. SiO2@ZrO2(am) induced genotoxic action only at 10 and 50 µg/mL (comet and MN assays), along with a decrease of the GSH/GSSG ratio at 50 µg/mL. Both particles were found inside the cells, forming vesicles; however, none of them entered the nucleus. Our findings show that crystallization of the shell of the amorphous ZrO2 increases both cytotoxicity and genotoxicity.


Subject(s)
DNA Damage/drug effects , Materials Testing/methods , Silicon Dioxide/pharmacology , Zirconium/chemistry , Cell Line, Tumor , Cell Survival/drug effects , Chemical Phenomena , Comet Assay , Humans , Micronucleus Tests , Osteosarcoma/metabolism , Particle Size , Reactive Oxygen Species/metabolism
10.
J Appl Microbiol ; 116(6): 1438-46, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24528382

ABSTRACT

AIMS: To evaluate the antibacterial efficacy of silicate bioactive glass nanoparticles/collagen composites functionalized with tetracycline hydrochloride (TCH). METHODS AND RESULTS: Different concentrations of tetracycline hydrochloride (TCH) were incorporated on silicate bioactive glass nanoparticles/collagen composites by dipping these biomaterials for 48 h at 37°C in a solution of simulated body fluid (SBF) plus 0·05, 0·20 or 0·35 mg ml(-1) of the antibiotic. TCH release was assessed in double-distilled water at 37°C up to 72 h. The antibacterial activity of the samples has been evaluated in two ways: inhibition zone test and plate count method. The experiments were performed in vitro up to 48 h on four staphylococci strains (Staphylococcus aureus ATCC29213, ATCC25923, ATCC6538P and Staphylococcus epidermidis ATCC12228). The new composites were also tested for cytotoxicity on MG-63 human osteosarcoma cells. The results showed that the incorporation and release of TCH was dependent on the initial concentration of TCH in SBF. The biomaterials also inhibited the Staph. aureus cell growth even though the efficacy was similar for all concentration. On the other hand, no cytotoxic effects were found on osteoblast-like cells, even at the highest concentration. CONCLUSIONS: Considering all results, it can be concluded that the new composite acts as a suitable bioactive carrier of TCH and could have potential in the prevention of biomaterial related infections. SIGNIFICANCE AND IMPACT OF THE STUDY: The results suggest a potential application as wound dressing.


Subject(s)
Anti-Bacterial Agents/pharmacology , Biocompatible Materials/pharmacology , Nanocomposites/chemistry , Tetracycline/pharmacology , Anti-Bacterial Agents/chemistry , Biocompatible Materials/chemistry , Body Fluids , Cell Line, Tumor , Collagen/chemistry , Glass/chemistry , Humans , Osteoblasts/drug effects , Staphylococcus aureus/drug effects , Staphylococcus epidermidis/drug effects
11.
J Biol Inorg Chem ; 19(1): 59-74, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24233155

ABSTRACT

Flavonoids are a large family of polyphenolic compounds synthesized by plants. They display interesting biological effects mainly related to their antioxidant properties. On the other hand, vanadium compounds also exhibit different biological and pharmacological effects in cell culture and in animal models. Since coordination of ligands to metals can improve or change the pharmacological properties, we report herein, for the first time, a detailed study of the mechanisms of action of an oxidovanadium(IV) complex with the flavonoid silibinin, Na2[VO(silibinin)2]·6H2O (VOsil), in a model of the human osteosarcoma derived cell line MG-63. The complex inhibited the viability of osteosarcoma cells in a dose-dependent manner with a greater potency than that of silibinin and oxidovanadium(IV) (p < 0.01), demonstrating the benefit of complexation. Cytotoxicity and genotoxicity studies also showed a concentration effect for VOsil. The increase in the levels of reactive oxygen species and the decrease of the ratio of the amount of reduced glutathione to the amount of oxidized glutathione were involved in the deleterious effects of the complex. Besides, the complex caused cell cycle arrest and activated caspase 3, triggering apoptosis as determined by flow cytometry. As a whole, these results show the main mechanisms of the deleterious effects of VOsil in the osteosarcoma cell line, demonstrating that this complex is a promising compound for cancer treatments.


Subject(s)
Antineoplastic Agents/pharmacology , Cell Proliferation/drug effects , Coordination Complexes/pharmacology , Osteosarcoma/drug therapy , Silymarin/pharmacology , Vanadates/pharmacology , Antineoplastic Agents/chemistry , Apoptosis/drug effects , Cell Line, Tumor , Coordination Complexes/chemistry , Humans , Osteosarcoma/pathology , Silybin , Silymarin/chemistry , Vanadates/chemistry
12.
J Inorg Biochem ; 134: 106-17, 2014 May.
Article in English | MEDLINE | ID: mdl-24199985

ABSTRACT

We report herein the antitumor actions of three oxidovanadium(IV) complexes on MG-63 human osteosarcoma cell line. The three complexes: VO(oda), VO(oda)bipy and VO(oda)phen (oda=oxodiacetate), caused a concentration dependent inhibition of cell viability. The antiproliferative action of VO(oda)phen could be observed in the whole range of concentrations (at 2.5 µM), while VO(oda)bipy and VO(oda) showed a decrease of cell viability only at higher concentrations (at 50 and 75 µM, respectively) (p<0.01). Moreover, VO(oda)phen caused a decrease of lysosomal and mitochondrial activities at 2.5 µM, while VO(oda) and VO(oda)bipy affected neutral red uptake and mitochondrial metabolism at 50 µM (p<0.01). On the other hand, no DNA damage studied by the Comet assay could be observed in MG-63 cells treated with VO(oda) at 2.5-10 µM. Nevertheless, VO(oda)phen and VO(oda)bipy induced DNA damage at 2.5 and 10 µM, respectively (p<0.01). The generation of reactive oxygen species increased at 10 µM of VO(oda)phen and only at 100 µM of VO(oda) and VO(oda)bipy (p<0.01). Besides, VO(oda)phen and VO(oda)bipy triggered apoptosis as determined by externalization of the phosphatidylserine. The determination of DNA cleavage by agarose gel electrophoresis showed that the ability of VO(oda)(bipy) is similar to that of VO(oda), while VO(oda)(phen) showed the highest nuclease activity in this series. Overall, our results showed a good relationship between the bioactivity of the complexes and their structures since VO(oda)phen presented the most potent antitumor action in human osteosarcoma cells followed by VO(oda)bipy and then by VO(oda) according to the number of intercalating heterocyclic moieties.


Subject(s)
2,2'-Dipyridyl/chemistry , Acetates/chemistry , Antineoplastic Agents/pharmacology , Coordination Complexes/pharmacology , Phenanthrolines/chemistry , Vanadium/chemistry , Antineoplastic Agents/chemical synthesis , Cell Line, Tumor , Cell Survival/drug effects , Comet Assay , Coordination Complexes/chemical synthesis , DNA Fragmentation/drug effects , Humans , Inhibitory Concentration 50 , Lysosomes/drug effects , Lysosomes/metabolism , Mitochondria/drug effects , Mitochondria/metabolism , Neutral Red/metabolism , Phosphatidylserines/metabolism , Reactive Oxygen Species/metabolism
13.
Dalton Trans ; 42(33): 11868-80, 2013 Sep 07.
Article in English | MEDLINE | ID: mdl-23760674

ABSTRACT

Flavonoids, a polyphenolic compound family, and the vanadium compounds have interesting biological, pharmacological, and medicinal properties. We report herein the antitumor actions of the complex [VO(chrysin)2EtOH]2 (VOchrys) on the MG-63 human osteosarcoma cell line. Oxovanadium(IV), chrysin and VOchrys caused a concentration-dependent inhibition of cell viability. The complex was the strongest antiproliferative agent (p < 0.05). Cytotoxicity and genotoxicity studies also showed a concentration effect. Reactive oxygen species (ROS) and the alterations in the GSH/GSSG ratio underlie the main mechanisms of action of VOchrys. Additions of ROS scavengers (vitamin C plus vitamin E) or GSH to the viability experiments demonstrated beneficial effects (p < 0.01). Besides, the complex triggered apoptosis, disruption of the mitochondria membrane potential (MMP), increased levels of caspase 3 and DNA fragmentation measured by the sub-G1 peak in cell cycle arrest experiments (p < 0.01). Collectively, VOchrys is a cell death modulator and a promissory complex to be used in cancer treatments.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Flavonoids/chemistry , Organometallic Compounds/pharmacology , Osteosarcoma/drug therapy , Oxidative Stress/drug effects , Vanadates/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Organometallic Compounds/chemical synthesis , Organometallic Compounds/chemistry , Osteosarcoma/pathology , Structure-Activity Relationship
14.
Minerva Gastroenterol Dietol ; 59(1): 97-105, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23478247

ABSTRACT

AIM: Gastric juice may constitute a precious source of clinicopathological information. We assessed the usefulness of real-time, perendoscopic, gastric juice pH determination in identifying preneoplastic conditions of the stomach, that often escape the mere endoscopic evaluation. METHODS: The study included 245 patients (115M; 130F; age 47±17). In each of them perendoscopic gastric juice pH was assessed by means of an innovative device, the Endofaster, and the results were correlated with histological evaluation (H&E, immunohistochemistry, argyrophil stains), and gastric acid secretion (BAO-PAO), and serum gastrin levels. The conditions evaluated were: atrophy, intestinal metaplasia, endocrine cell hyperplasia, hypergastrinemia. RESULTS: A total of 136 pathological conditions were detected and these resulted to be correlated with pH (r=0.67; P<0.01). The rate of pathological conditions was low in normochlorhydric patients (14.1%); most of these conditions were concentrated in patients with hypochlorhydria (85.9%) (P<0.001). Specifically, the number of patients with one or more pathological conditions increased proportionately with the rise in pH levels. An inverse correlation was detected between gastric juice pH and basal acid output (BAO) (r=-0.72; P<0.01). Endoscopic feature was normal/mild in most of patients with pathological conditions. CONCLUSION: Hypochlorhydria is a sensitive indicator of gastric risk conditions. Perendoscopic real-time assessment of pH can improve and extend optical analysis by allowing the detection of pathological conditions (either preneoplastic or not) that often escape diagnosis because not correlated with specific endoscopic pattern.


Subject(s)
Gastroscopy , Precancerous Conditions/pathology , Stomach/pathology , Female , Humans , Hydrogen-Ion Concentration , Male , Middle Aged
15.
Cell Prolif ; 46(2): 172-82, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23510472

ABSTRACT

OBJECTIVES: In this study, we have evaluated effects of 24-hour treatments with simvastatin or rosuvastatin on RAS protein, NF-κB and MMP expression in LC tissues obtained from 12 patients undergoing thoracic surgery. MATERIALS AND METHODS: Normal and lung tumour tissues obtained from each sample were exposed to simvastatin (2.5-30 µm) or rosuvastatin (1.25-30 µm) and western blot analysis was then performed. RESULTS: We documented increased expression of proteins, MMP-2, MMP-9 and NF-κB-p65 in LC tissues, with respect to normal tissues (P < 0.01). In the malignant tissues, simvastatin and rosuvastatin significantly (P < 0.01) and dose-dependently reduced RAS protein, MMP-2/9 and NF-κB-p65 expression. CONCLUSIONS: In conclusion, our results suggest that simvastatin and rosuvastatin could play a role in LC treatment by modulation of RAS protein, MMP-2/9 and NF-κB-p65.


Subject(s)
Adenocarcinoma/pathology , Fluorobenzenes/pharmacology , Lung Neoplasms/pathology , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/metabolism , Pyrimidines/pharmacology , Simvastatin/pharmacology , Sulfonamides/pharmacology , Transcription Factor RelA/metabolism , ras Proteins/metabolism , Adenocarcinoma/enzymology , Adenocarcinoma/metabolism , Adenocarcinoma of Lung , Aged , Antineoplastic Agents/pharmacology , Biomarkers, Tumor/metabolism , Blotting, Western , Case-Control Studies , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical , Female , Gene Expression Regulation, Neoplastic , Humans , Lung/drug effects , Lung/metabolism , Lung/pathology , Lung Neoplasms/enzymology , Lung Neoplasms/metabolism , Male , Matrix Metalloproteinase 2/genetics , Matrix Metalloproteinase 9/genetics , Middle Aged , Rosuvastatin Calcium , Smoking/adverse effects , Transcription Factor RelA/genetics , Tumor Cells, Cultured , ras Proteins/genetics
16.
J Colloid Interface Sci ; 394: 147-56, 2013 Mar 15.
Article in English | MEDLINE | ID: mdl-23261339

ABSTRACT

Spherical particles with an amorphous core of silica and a crystalline shell of titanium oxide (SiO(2)@TiO(2)) formed in a three-step procedure, being the last step a mild chemical treatment. SiO(2)@TiO(2) had a shell with pores (micro and mesopores) permeating between TiO(2) nanocrystals (anatase) and a solid core of amorphous silica. The spheres had an outstanding specific surface area (300 m(2) g(-1)). A cyto- and genotoxic study of SiO(2)@TiO(2) and titanium oxide nanoparticles (TiO(2)-NP) on UMR106 cells with 24h exposure showed that SiO(2)@TiO(2) colloidal particles were less toxic than TiO(2)-NP.


Subject(s)
Cytotoxins/toxicity , Mutagens/toxicity , Nanoparticles/toxicity , Silicon Dioxide/toxicity , Titanium/toxicity , Animals , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Cytotoxins/chemistry , Mutagens/chemistry , Nanoparticles/chemistry , Osteoblasts/cytology , Osteoblasts/drug effects , Osteoblasts/metabolism , Particle Size , Rats , Reactive Oxygen Species/metabolism , Silicon Dioxide/chemistry , Titanium/chemistry
17.
Mol Cell Biochem ; 376(1-2): 53-61, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23238873

ABSTRACT

Norfloxacin is a fluoroquinolone antibiotic used in the treatment of bacterial infections. In this article, we studied the potential antitumoral action of a complex of Norfloxacin with Cu(II), Cu(Nor)(2)·5H(2)O on osteosarcoma cells (UMR106) and calvaria-derived cells (MC3T3-E1), evaluating its cytotoxicity and genitoxicity. We have also elucidated the more stable conformation of this complex under physiologic conditions by Molecular Dynamic simulations based on the model of the canonical ensemble and PM6 force field. When solvent effect was taken into account, the complex conformation with both carbonyl groups in opposite sides displayed lower energy. Cu(Nor)(2)·5H(2)O caused an inhibitory effect on the proliferation on both cell lines from 300 µM (P < 0.01). Nevertheless, the decline on cell proliferation of UMR106 cells was more pronounced (45 % vs basal) than in MC3T3-E1 cells (20 % vs basal) at 300 µM (P < 0.01). Cu(Nor)(2)·5H(2)O altered lysosomal metabolism (Neutral Red assay) in a dose-dependent manner from 300 µM (P < 0.001). Morphological studies showed important transformations that correlated with a decrease in the number of cells in a dose-dependent manner. Moreover, Cu(Nor)(2)·5H(2)O caused statistically significant genotoxic effects on both osteoblast cell lines in a lower range of concentrations (Micronucleus assay) (P < 0.05 at 10 µM, P < 0.001 from 25 to 50 µM). UMR106 cells displayed a dose-related genotoxic effect between 5 and 25 µM while the MC3T3-E1 cells showed a narrower concentration dependent range. Altogether, these results suggest that Cu(Nor)(2)·5H(2)O is a good candidate to be further evaluated for alternative therapeutics in cancer treatment.


Subject(s)
Antineoplastic Agents/pharmacology , Bone Neoplasms/drug therapy , Coordination Complexes/pharmacology , Copper/chemistry , Osteosarcoma/drug therapy , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/toxicity , Bone Neoplasms/pathology , Cell Line , Cell Line, Tumor , Cell Proliferation/drug effects , Coordination Complexes/chemical synthesis , Coordination Complexes/chemistry , Copper/pharmacology , Drug Screening Assays, Antitumor/methods , Lysosomes/drug effects , Mice , Micronucleus Tests , Molecular Dynamics Simulation , Mutagenicity Tests , Norfloxacin/chemical synthesis , Norfloxacin/chemistry , Norfloxacin/pharmacology , Osteoblasts/drug effects , Osteosarcoma/pathology , Rats
18.
Med Chem ; 6(1): 9-23, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20402656

ABSTRACT

Strong chelating ligands as oxodiacetate (oda) are model systems to study the process of metal trapping by living organisms. Vanadium compounds display interesting biological and pharmacological actions. In vertebrates, vanadium is stored mainly in bones. In the present study we report the effects of the complex of oda with vanadyl(IV) cation, VO(oda), on two osteoblast cell lines, one normal (MC3T3E1) and the other tumoral (UMR106). VO(oda) exerted cytotoxic actions in osteoblasts as it was determined through a dose-dependent decrease in cell proliferation, and morphological and actin alterations. The putative mechanisms underlying VO(oda) deleterious effects were also investigated. The complex increased the level of ROS which correlated with a decreased in GSH/GSSG ratio. Besides, VO(oda) induced a dissipation of the mitochondria membrane potential (MMP) and promoted an increase in ERK cascade phosphorylation, which is involved in the regulation of cellular death and survival. All the effects were more pronounced in MC3T3-E1 than in UMR106 cells. ERK activation was inhibited by PD98059, Wortmanin and the ROS scavenger NAC (N-acetyl cysteine). These results suggest that VO(oda) stimulated ERKs phosphorilation by induction of free radicals involving kinases upstream of ERK pathway. The inhibitory effect of the complex on cell proliferation was partially reversed in both cell lines by NAC. Moreover, PD98059 and Wortmanin also partially reversed the inhibition of cell proliferation in the tumoral osteoblasts. The use of specific inhibitors and ROS scavengers suggested the involvement of oxidative stress, MMP alterations and ERK pathway in the apoptotic actions of this complex.


Subject(s)
Cytotoxins/chemistry , Cytotoxins/pharmacology , Organometallic Compounds/chemistry , Organometallic Compounds/pharmacology , Osteoblasts/drug effects , Oxygen/chemistry , Vanadium/chemistry , Actins/metabolism , Animals , Cell Death/drug effects , Cell Line, Tumor , Cytoskeleton/drug effects , Cytoskeleton/metabolism , Enzyme Activation/drug effects , Glutathione/metabolism , Glutathione Disulfide/metabolism , Intracellular Space/drug effects , Membrane Potential, Mitochondrial/drug effects , Mice , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Neutral Red , Osteoblasts/cytology , Osteoblasts/metabolism , Rats , Reactive Oxygen Species/metabolism
19.
J Hazard Mater ; 177(1-3): 711-8, 2010 May 15.
Article in English | MEDLINE | ID: mdl-20079968

ABSTRACT

The aim of this study was to analyze the cytotoxicity and genotoxicity of titanium oxide (TiO(2)) and aluminium oxide (Al(2)O(3)) nanoparticles (NPs) on Chinese hamster ovary (CHO-K1) cells using neutral red (NR), mitochondrial activity (by MTT assay), sister chromatid exchange (SCE), micronucleus (MN) formation, and cell cycle kinetics techniques. Results showed a dose-related cytotoxic effect evidenced after 24h by changes in lysosomal and mitochondrial dehydrogenase activity. Interestingly, transmission electronic microscopy (TEM) showed the formation of perinuclear vesicles in CHO-K1 cells after treatment with both NPs during 24h but no NP was detected in the nuclei. Genotoxic effects were shown by MN frequencies which significantly increased at 0.5 and 1 microg/mL TiO(2) and 0.5-10 microg/mL Al(2)O(3). SCE frequencies were higher for cells treated with 1-5 microg/mL TiO(2). The absence of metaphases evidenced cytotoxicity for higher concentrations of TiO(2). No SCE induction was achieved after treatment with 1-25 microg/mL Al(2)O(3). In conclusion, findings showed cytotoxic and genotoxic effects of TiO(2) and Al(2)O(3) NPs on CHO-K1 cells. Possible causes of controversial reports are discussed further on.


Subject(s)
Aluminum Oxide/pharmacology , Cytotoxins/pharmacology , Mutagens/pharmacology , Titanium/pharmacology , Aluminum Oxide/toxicity , Animals , CHO Cells , Cricetinae , Cricetulus , Dose-Response Relationship, Drug , Nanoparticles/toxicity , Titanium/toxicity , Toxicity Tests
20.
Food Chem Toxicol ; 47(2): 472-9, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19110027

ABSTRACT

Semicarbazide (SEM) is an azodicarbonamide by-product present in glass jar packaged foods including babyfoods, in bleaching steps and flour treatment. Experimental data showed SEM acting as osteolathyrogen agent, but few toxicological data are available in susceptible life-stages. This study aimed to evaluate effects of SEM oral administration for 28 days at 0, 40, 75, 140 mg/kg bw day during the juvenile period in Sprague-Dawley rats. Histopatological examinations of: epiphyseal cartilage - potential target of SEM lathyrogen action - testes, ovary, uterus, thyroid, thymus, spleen, adrenals, representative of the main developing organs relevant to juvenile toxicity, and neurobehavioural tests in males, were performed. Mortality at high and mid dose levels and significantly decreased body weight gain were observed in males even at the lowest dose. Lack of mineralization in cartilage at all dose levels was present. Marked alterations of spontaneous motor and exploratory behaviours were evident even at 40 mg/kg. Histological alterations were observed in all tissues; thyroid and ovary effects were present also at 40 mg/kg. The present study indicate that the NOAEL in juvenile rats is lower than 40 mg/kg for SEM oral administration. SEM administration during juvenile period exerted pleiotropic effects and further studies are suggested to elucidate mechanisms.


Subject(s)
Carcinogens, Environmental/toxicity , Consumer Product Safety , Food Contamination , Semicarbazides/toxicity , Age Factors , Animals , Behavior, Animal/drug effects , Dose-Response Relationship, Drug , Eating/drug effects , Exploratory Behavior/drug effects , Female , Genitalia/drug effects , Genitalia/pathology , Growth Plate/drug effects , Growth Plate/pathology , Longevity/drug effects , Male , Maze Learning/drug effects , Motor Activity/drug effects , No-Observed-Adverse-Effect Level , Organ Size/drug effects , Rats , Rats, Sprague-Dawley , Weight Gain/drug effects
SELECTION OF CITATIONS
SEARCH DETAIL
...