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1.
Oral Oncol ; 44(11): 1073-9, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18620899

ABSTRACT

In this study, oral carcinoma cells were used to evaluate chloroaluminum-phthalocyanine encapsulated in liposomes as the photosensitizer agent in support of photodynamic therapy (PDT). The genotoxicity and cytotoxicity behavior of the encapsulated photosensitizer in both dark and under irradiation using the 670-nm laser were investigated with the classical trypan blue cell viability test, the acridine orange/ethidium bromide staining organelles test, micronucleus formation frequency, DNA fragmentation, and cell morphology. The cell morphology investigation was carried out using light and electronic microscopes. Our findings after PDT include reduction in cell viability (95%) associated with morphologic alterations. The neoplastic cell destruction was predominantly started by a necrotic process, according to the assay with acridine orange and ethidium bromide, and this was confirmed by electronic microscopy analysis. Neither the PDT agent nor laser irradiation alone showed cytotoxicity, genotoxicity, or even morphologic alterations. Our results reinforce the efficiency of light-irradiated chloroaluminum-phthalocyanine in inducing a positive effect of PDT.


Subject(s)
Indoles/therapeutic use , Keratinocytes/drug effects , Mouth Neoplasms/drug therapy , Organometallic Compounds/therapeutic use , Photochemotherapy/methods , Radiation-Sensitizing Agents/therapeutic use , Acridine Orange , Cell Survival/drug effects , Coloring Agents , DNA Fragmentation/drug effects , Ethidium , Fluorescent Dyes , Humans , Keratinocytes/pathology , Microscopy/methods , Mouth Neoplasms/pathology , Necrosis , Treatment Outcome , Trypan Blue
2.
J Nanosci Nanotechnol ; 8(11): 5813-7, 2008 Nov.
Article in English | MEDLINE | ID: mdl-19198310

ABSTRACT

In this study the interaction between magnetic nanoparticles (MNPs) surface-coated with meso-2,3-dimercaptosuccinic acid (DMSA) with both bovine serum albumin (BSA) and human serum albumin (HSA) was investigated. The binding of the MNP-DMSA was probed by the fluorescence quenching of the BSA and HSA tryptophan residue. Magnetic resonance and light microscopy analyses were carried out in in vivo tests using female Swiss mice. The binding constants (Kb) and the complex stoichiometries (n) indicate that MNP-DMSA/BSA and MNP-DMSA/HSA complexes have low association profiles. After five minutes following intravenous injection of MNP-DMSA into mice's blood stream we found the lung firstly target by the MNP-DMSA, followed by the liver in a latter stage. This finding suggests that the nanoparticle's DMSA-coating process probably hides the thiol group, through which albumin usually binds. This indicates that biocompatible MNP-DMSA is a very promising material system to be used as a drug delivery system (DDS), primarily for lung cancer treatment.


Subject(s)
Crystallization/methods , Drug Carriers/chemistry , Ferric Compounds/chemistry , Magnetics , Nanomedicine/methods , Nanostructures/chemistry , Serum Albumin/chemistry , Succimer/chemistry , Adsorption , Binding Sites , Coated Materials, Biocompatible/chemistry , Macromolecular Substances/chemistry , Materials Testing , Molecular Conformation , Nanostructures/ultrastructure , Particle Size , Protein Binding , Surface Properties
3.
J Nanosci Nanotechnol ; 6(8): 2413-5, 2006 Aug.
Article in English | MEDLINE | ID: mdl-17037849

ABSTRACT

The aim of this study was to prepare bovine serum albumin-based beads containing maghemite nanoparticles incorporated via ionic magnetic fluid and to evaluate the cell toxicity of this biocompatible system using the J774-A1 cell line. Transmission electron micrographs obtained from the magnetic fluid sample were used to estimate the average particle diameter around 7.6 nm and diameter dispersion of 0.22. The BSA-based magnetic beads were prepared using the heat protein denaturation route. The nanoparticle concentration in the magnetic fluid sample used for the synthesis of the magnetic beads was in the range of 1.2 x 10(16) to 2.3 x 10(17) particle/ml. The methodology used to investigate the cell toxicity of the magnetic beads was the classical MTT assay. Our observation showed that the toxicity against the J774-A1 cell line depends upon the amount of magnetic material incorporated into the magnetic nanobeads and was found to be 14, 11, 9, 5, and 3% for 2.3 x 10(17), 1.2 x 10(17), 4.6 x 10(16), 2.3 x 10(16), and 1.2 x 10(16) particle/ml, respectively.


Subject(s)
Albumins/chemistry , Magnetics , Nanoparticles/toxicity , Nanotechnology/methods , Animals , Biotechnology/methods , Cell Line , Ions , Mice , Microscopy, Electron, Transmission , Models, Molecular , Nanoparticles/chemistry , Serum Albumin/chemistry , Tetrazolium Salts/pharmacology , Thiazoles/pharmacology , Time Factors
4.
Braz. j. med. biol. res ; 37(10): 1491-1496, Oct. 2004. tab
Article in English | LILACS | ID: lil-383028

ABSTRACT

The aim of the present study was to investigate the effects of daily intragastric administration of bullfrog oil (oleic, linoleic and palmitoleic acid-rich oil), corresponding to 0.4 percent of body weight for four weeks, on fatty acid composition and oxidative stress (lipid peroxidation and catalase activity) in mouse liver. The activities of aspartate aminotransferase (AST), alkaline phosphatase (ALP), alanine aminotransferase (ALT), and gamma-glutamyltransferase (GGT), biomarkers of tissue injury, were determined in liver homogenates and serum. The proportions of 18:2n-6, 20:4n-6, 20:5n-3, and 22:6n-3 (polyunsaturated fatty acids, from 37 to 60 percent) in the total fatty acid content were increased in the liver of the bullfrog oil-treated group (P < 0.05) compared to control. At the same time, a significant decrease in the relative abundance of 14:0, 16:0, and 18:0 (saturated fatty acids, from 49 to 25 percent) was observed. The hepatic content of thiobarbituric acid reactive substances (TBARS) was increased from 2.3 ± 0.2 to 12.3 ± 0.3 nmol TBA-MDA/mg protein and catalase activity was increased from 840 ± 32 to 1110 ± 45 æmol reduced H2O2 min-1 mg protein-1 in the treated group. Bullfrog oil administration increased AST and ALP activities in the liver (from 234.10 ± 0.12 to 342.84 ± 0.13 and 9.38 ± 0.60 to 20.06 ± 0.27 U/g, respectively) and in serum (from 95.41 ± 6.13 to 120.32 ± 3.15 and 234.75 ± 11.5 to 254.41 ± 2.73 U/l, respectively), suggesting that this treatment induced tissue damage. ALT activity was increased from 287.28 ± 0.29 to 315.98 ± 0.34 U/g in the liver but remained unchanged in serum, whereas the GGT activity was not affected by bullfrog oil treatment. Therefore, despite the interesting modulation of fatty acids by bullfrog oil, a possible therapeutic use requires care since some adverse effects were observed in liver.


Subject(s)
Animals , Male , Mice , Catalase , Dietary Fats, Unsaturated , Fatty Acids , Lipid Peroxidation , Liver , Oxidative Stress , Alkaline Phosphatase , Biomarkers , gamma-Glutamyltransferase , Rana catesbeiana , Thiobarbituric Acid Reactive Substances , Transaminases
5.
Braz J Med Biol Res ; 37(10): 1491-6, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15448869

ABSTRACT

The aim of the present study was to investigate the effects of daily intragastric administration of bullfrog oil (oleic, linoleic and palmitoleic acid-rich oil), corresponding to 0.4% of body weight for four weeks, on fatty acid composition and oxidative stress (lipid peroxidation and catalase activity) in mouse liver. The activities of aspartate aminotransferase (AST), alkaline phosphatase (ALP), alanine aminotransferase (ALT), and gamma-glutamyltransferase (GGT), biomarkers of tissue injury, were determined in liver homogenates and serum. The proportions of 18:2n-6, 20:4n-6, 20:5n-3, and 22:6n-3 (polyunsaturated fatty acids, from 37 to 60%) in the total fatty acid content were increased in the liver of the bullfrog oil-treated group (P < 0.05) compared to control. At the same time, a significant decrease in the relative abundance of 14:0, 16:0, and 18:0 (saturated fatty acids, from 49 to 25%) was observed. The hepatic content of thiobarbituric acid reactive substances (TBARS) was increased from 2.3 +/- 0.2 to 12.3 +/- 0.3 nmol TBA-MDA/mg protein and catalase activity was increased from 840 +/- 32 to 1110 +/- 45 micromol reduced H2O2 min-1 mg protein-1 in the treated group. Bullfrog oil administration increased AST and ALP activities in the liver (from 234.10 +/- 0.12 to 342.84 +/- 0.13 and 9.38 +/- 0.60 to 20.06 +/- 0.27 U/g, respectively) and in serum (from 95.41 +/- 6.13 to 120.32 +/- 3.15 and 234.75 +/- 11.5 to 254.41 +/- 2.73 U/l, respectively), suggesting that this treatment induced tissue damage. ALT activity was increased from 287.28 +/- 0.29 to 315.98 +/- 0.34 U/g in the liver but remained unchanged in serum, whereas the GGT activity was not affected by bullfrog oil treatment. Therefore, despite the interesting modulation of fatty acids by bullfrog oil, a possible therapeutic use requires care since some adverse effects were observed in liver.


Subject(s)
Catalase/drug effects , Fatty Acids, Unsaturated/pharmacology , Fatty Acids/analysis , Lipid Peroxidation/drug effects , Liver/drug effects , Oxidative Stress/drug effects , Alkaline Phosphatase/analysis , Animals , Biomarkers/analysis , Catalase/physiology , Liver/metabolism , Male , Mice , Rana catesbeiana , Thiobarbituric Acid Reactive Substances/analysis , Transaminases/analysis , gamma-Glutamyltransferase/analysis
6.
Braz. j. med. biol. res ; 34(5): 683-687, May 2001. tab
Article in English | LILACS | ID: lil-285867

ABSTRACT

Human and animal immune functions present sex dimorphism that seems to be mainly regulated by sex hormones. In the present study, the activities of the antioxidant enzymes total superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) were measured in intraperitoneal resident macrophages from adult male and female rats. In addition to comparing males and females, we also examined the regulation of these enzyme activities in macrophages by sex steroids. GSH-Px activity did not differ between male and female macrophages. However, both total SOD and CAT activities were markedly higher in females than in males (83 and 180 percent). Removal of the gonads in both males and females (comparison between castrated groups) increased the difference in SOD activity from 83 to 138 percent and reduced the difference in CAT activity from 180 to 86 percent. Castration and testosterone administration did not significantly modify the activities of the antioxidant enzymes in male macrophages. Ovariectomy did not affect SOD or GSH-Px activity but markedly reduced (48 percent) CAT activity. This latter change was fully reversed by estrogen administration, whereas progesterone had a smaller effect. These results led us to conclude that differences in the SOD and CAT activities may partially explain some of the differences in immune function reported for males and females. Also, estrogen is a potent regulator of CAT in macrophages and therefore this enzyme activity in macrophages may vary considerably during the menstrual cycle


Subject(s)
Animals , Female , Rats , Antioxidants/metabolism , Gonadal Steroid Hormones/pharmacology , Lipid Peroxidation/drug effects , Macrophages, Peritoneal/drug effects , Oxidoreductases/metabolism , Castration , Catalase/metabolism , Estrogens/pharmacology , Glutathione Peroxidase/metabolism , Macrophages, Peritoneal/enzymology , Oxidative Stress/drug effects , Rats, Wistar , Sex Characteristics , Superoxide Dismutase/metabolism , Testosterone/pharmacology
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