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1.
Sci Rep ; 14(1): 14712, 2024 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926453

RESUMO

Human health is becoming concerned about exposure to endocrine disrupting chemicals (EDCs) emanating from plastic, such as phthalates, which are industrially employed as plasticizers in the manufacturing of plastic products. Due to some toxicity concerns, di(2-ethylhexyl) phthalate (DEHP) was replaced by diisononyl phthalate (DiNP). Recent data, however, highlights the potential of DiNP to interfere with the endocrine system and influence allergic responses. Asthma affects brain function through hypoxia, systemic inflammation, oxidative stress, and sleep disturbances and its effective management is crucial for maintaining respiratory and brain health. Therefore, in DiNP-induced asthmatic mice, this study investigated possible crosstalk between the lungs and the brain inducing perturbations in neural mitochondrial antioxidant status, inflammation biomarkers, energy metabolizing enzymes, and apoptotic indicators. To achieve this, twelve (n = 12, 20-30 g) male BALB/c mice were divided into two (2) experimental groups, each with five (6) mice. Mice in group II were subjected to 50 mg/kg body weight (BW) DiNP (Intraperitoneal and intranasal), while group I served as the control group for 24 days. The effects of DiNP on neural energy metabolizing enzymes (Hexokinase, Aldolase, NADase, Lactate dehydrogenase, Complex I, II, II & IV), biomarkers of inflammation (Nitric oxide, Myeloperoxidase), oxidative stress (malondialdehyde), antioxidants (catalase, glutathione-S-transferase, and reduced glutathione), oncogenic and apoptotic factors (p53, K-ras, Bcl, etc.), and brain histopathology were investigated. DiNP-induced asthmatic mice have significantly (p < 0.05) altered neural energy metabolizing capacities due to disruption of activities of enzymes of glycolytic and oxidative phosphorylation. Other responses include significant inflammation, oxidative distress, decreased antioxidant status, altered oncogenic-apoptotic factors level and neural degeneration (as shown in hematoxylin and eosin-stained brain sections) relative to control. Current findings suggest that neural histoarchitecture, energy metabolizing potentials, inflammation, oncogenic and apoptotic factors, and mitochondrial antioxidant status may be impaired and altered in DiNP-induced asthmatic mice suggesting a pivotal crosstalk between the two intricate organs (lungs and brain).


Assuntos
Apoptose , Asma , Pulmão , Camundongos Endogâmicos BALB C , Mitocôndrias , Estresse Oxidativo , Ácidos Ftálicos , Animais , Apoptose/efeitos dos fármacos , Asma/metabolismo , Asma/induzido quimicamente , Asma/patologia , Estresse Oxidativo/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Camundongos , Masculino , Pulmão/metabolismo , Pulmão/patologia , Pulmão/efeitos dos fármacos , Respiração Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/efeitos dos fármacos
2.
Pharmaceuticals (Basel) ; 17(2)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38399387

RESUMO

The objective of the present work was to develop and optimize an intranasal in situ gel of Pramipexole dihydrochloride for enhanced drug delivery, better patient acceptability, and possible proper treatment of Parkinson's disease. Preliminary studies were performed to select formulation components and identify key variables affecting the formulation. The optimization of the in situ gelling system of Pramipexole dihydrochloride was achieved by applying 32 full factorial design using Design-Expert® software (Stat-Ease 9.0.6 version) and taking concentrations of Poloxamer 407 (X1) and HPMC K4M (X2) as independent variables. The gelling temperature, gel strength, and percentage of drug diffused after 8 h were taken as dependent variables. The software provided an optimized formulation, with 16.50% of X1 and 0.2% of X2 with the highest desirability. An in vivo drug retention time study was performed for the optimized formulation in Wistar rats. The results of the optimization process demonstrated that the selected gel formulation exhibited desirable characteristics, including gelation near body temperature, good gel strength, suitable viscosity, and sustained drug release. The optimized formulation displayed significantly higher drug retention, lasting about 5 h, versus the plain poloxamer gel formulation. Hence, it was concluded that the optimized formulation will remain affixed at the site of application for a significant time after intranasal administration and consequently sustain the release of the drug. The optimized formulation was found to be stable during the stability studies. The developed dosage form may improve patient compliance, enhance nasal drug residence, and offer sustained drug release. However, further clinical studies are necessary to validate these findings.

3.
Heliyon ; 10(4): e26126, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38384558

RESUMO

Poly-herbal therapies for chronic diseases like diabetes mellitus (DM) have been practiced in south Asia for centuries. One of such therapies comprises of Hordeum vulgare, Elettaria cardamomum and Cicer arietinum that have shown encouraging therapeutic potential in the treatment of diabetes and obesity. Therefore, poly-herbal granules (PHGs) of this formula were developed and investigated for their anti-diabetic and anti-obesity potential in obese-diabetic rats. The developed PHGs were chemical characterized and the virtual molecular docking was performed by Discovery studio visualizer (DSV) software. For in-vivo experiment, obesity in rats was induced with high-fat high-sugar diet. After that, diabetes was induced by alloxan monohydrate 150 mg/kg i.p. injection. The diseased rats were treated with PHGs at 250, 500 and 750 mg/kg/day for four weeks. GC-MS analysis of PHGs demonstrated the presence of 1,3-Benzenedicarboxylic acid bis(2-ethylhexyl) ester and 1,2-Benzenedicarboxylic acid di-isooctyl ester and phenol, 2,4-bis(1,1-dimethylethyl). Molecular docking of these compounds demonstrated higher binding energies with receptor than metformin against α-amylase and α-glucosidase. PHGs exhibited a decline in body weight, HbA1c, hyperlipidemia, hyperglycemia, and insulin resistance in diseased rats. The histopathological examination revealed that PHGs improved the alloxan-induced damage to the pancreas. Furthermore, PHGs increased the SOD, CAT and GSH while and the decreased the level of MDA in the liver, kidney and pancreas of diseased rats. Additionally, the PHGs had significantly downregulated the TNF-α and NF-κB while upregulated the expression of NrF-2. The current study demonstrated that the PHGs exhibited anti-diabetic and anti-obesity potential through amelioration of oxidative stress, NF-κB, TNF-α, and NrF-2 due to the presence of different phytochemicals.

4.
J Ethnopharmacol ; 323: 117716, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38190955

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Mimosa caesalpiniifolia (Sansão-do-Campo) is a native species of the caatinga in northeastern Brazil that has been studied for its potential anti-inflammatory and antidepressant activity. It is popularly consumed as a medicinal plant and its pharmacological benefits are evidenced in the literature. AIM OF THE STUDY: The present work was carried out to promote the chemical profile and evaluate the pharmacological activity of the dry extract and the ethyl acetate fraction obtained from the dry leaves of Mimosa caesalpiniifolia. MATERIALS AND METHODS: The leaves were collected in the municipality of Alfenas-MG and subjected to drying, followed by division in a knife mill. The preparation of the dry extract was carried out by the extraction method using simple percolation and the fraction was obtained by liquid-liquid partition. Part of the extractive solution was concentrated in a rotary evaporator followed by a drying process using the spray technique with the addition of colloidal silicon dioxide. The dry extract (33.33%) showed a higher yield in mass when compared to the yield of the ethyl acetate fraction (19.67%). The in vivo pharmacological evaluation was conducted with a total of 82 male Wistar rats that underwent cecal ligation and perforation surgery to induce the inflammatory process. One week after surgery, these animals were treated for 7 days with the dry extract and the ethyl acetate fraction and submitted to behavioral tests (open field and forced swimming). RESULTS: The chemical results were obtained through analysis by HPLC-PDA coupled to a mass spectrometer, enabling the verification of the presence of phenolic acids, flavonoids, aglycones, and glycosides, in addition to tannins. This corroborates with data present in the literature for the genus Mimosa sp. Some compounds had their structure determined, where they were identified as catechin (m/z 288.97), cassiaocidentalin A (m/z 560.75), and procyanidin B2 [(epi)catechin-(epi)catechin; m/z 576.83)]. It was found that the animals that were submitted to the treatment did not present statistically significant results, demonstrating that the pharmacological action evaluated in the test was not highlighted in this type of experiment. The groups that underwent treatment had an aggravated locomotor activity. CONCLUSIONS: The results found with the chemical study contributed to the knowledge of the plant species studied. On the other hand, further studies are needed to provide a better understanding of the pharmacological evaluation of Mimosa caesalpiniifolia.


Assuntos
Acetatos , Catequina , Mimosa , Ratos , Animais , Ratos Wistar , Mimosa/química , Extratos Vegetais/farmacologia , Extratos Vegetais/análise , Folhas de Planta/química
5.
Front Plant Sci ; 14: 1225612, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37662142

RESUMO

Paris polyphylla Smith (Melanthiaceae) family, which is native to the Himalayan region, has received a lot of attention recently due to its extensive history of usage in traditional medicine. The production of steroidal saponin from callus suspension cultures of P. polyphylla was observed in the current study. The current study attempted to develop a P. polyphylla plant callus suspension culture through optimization of cultivation technique for callus suspension, quantification of total phenolic components and estimation of the extract's antioxidant activity. A light-yellow callus was formed within six weeks of cultivating rhizomes on Murashige and Skoog (MS) media supplemented with Thidiazuron (TDZ). Furthermore, the effect of TDZ, Methyl Jasmonate (MeJA), and Yeast Extract (YE) on callus growth, steroidal saponin (dioscin and diosgenin), total phenolic content, total flavonoids, total tannin, and total antioxidant activity was also measured. The medium containing 0.5 µM TDZ depicted the maximum callus biomass (2.98 g fresh weight). Significantly high phenolic and tannin content was observed in the MS medium containing 50 µM MeJA, whereas, no significant increase was observed in total tannin production in any treatment. Three in vitro assays, DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azino-bis (3-ethylbenzothiazoline- 6-sulfonic acid)) and FRAP (ferric ion reducing antioxidant potential) and FC (Folin-Ciocalteu), were used to assess antioxidant potential of callus. Maximum antioxidant analysis reported in 1.0 µM TDZ (6.89 mM AAE/100 g) containing medium followed by 50 µM MeJA (6.44 mM AAE/100 g). The HPLC analysis showed a high presence of dioscin and diosgenin (5.43% and 21.09%, respectively) compared to the wild sample (2.56% and 15.05%, respectively). According to the results, callus produced on media supplemented with 50 µM MeJA have significant phenolic contents and elevated antioxidant activity; nevertheless, callus growth was greater in the presence of 0.5 µM TDZ. The findings of the current study have commercial implications since greater biomass production will result in active phytochemicals that the pharmaceutical and nutraceutical sectors are in need desperately.

6.
Part Fibre Toxicol ; 19(1): 30, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35449069

RESUMO

BACKGROUND: Considering the expanding industrial applications of carbon nanotubes (CNTs), safety assessment of these materials is far less than needed. Very few long-term in vivo studies have been carried out. This is the first 2-year in vivo study to assess the effects of double walled carbon nanotubes (DWCNTs) in the lung and pleura of rats after pulmonary exposure. METHODS: Rats were divided into six groups: untreated, Vehicle, 3 DWCNT groups (0.12 mg/rat, 0.25 mg/rat and 0.5 mg/rat), and MWCNT-7 (0.5 mg/rat). The test materials were administrated by intratracheal-intrapulmonary spraying (TIPS) every other day for 15 days. Rats were observed without further treatment until sacrifice. RESULTS: DWCNT were biopersistent in the rat lung and induced marked pulmonary inflammation with a significant increase in macrophage count and levels of the chemotactic cytokines CCL2 and CCL3. In addition, the 0.5 mg DWCNT treated rats had significantly higher pulmonary collagen deposition compared to the vehicle controls. The development of carcinomas in the lungs of rats treated with 0.5 mg DWCNT (4/24) was not quite statistically higher (p = 0.0502) than the vehicle control group (0/25), however, the overall incidence of lung tumor development, bronchiolo-alveolar adenoma and bronchiolo-alveolar carcinoma combined, in the lungs of rats treated with 0.5 mg DWCNT (7/24) was statistically higher (p < 0.05) than the vehicle control group (1/25). Notably, two of the rats treated with DWCNT, one in the 0.25 mg group and one in the 0.5 mg group, developed pleural mesotheliomas. However, both of these lesions developed in the visceral pleura, and unlike the rats administered MWCNT-7, rats administered DWCNT did not have elevated levels of HMGB1 in their pleural lavage fluids. This indicates that the mechanism by which the mesotheliomas that developed in the DWCNT treated rats is not relevant to humans. CONCLUSIONS: Our results demonstrate that the DWCNT fibers we tested are biopersistent in the rat lung and induce chronic inflammation. Rats treated with 0.5 mg DWCNT developed pleural fibrosis and lung tumors. These findings demonstrate that the possibility that at least some types of DWCNTs are fibrogenic and tumorigenic cannot be ignored.


Assuntos
Neoplasias Pulmonares , Mesotelioma , Nanotubos de Carbono , Animais , Exposição por Inalação/efeitos adversos , Pulmão , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/patologia , Mesotelioma/patologia , Nanotubos de Carbono/toxicidade , Pleura , Ratos
7.
Toxins (Basel) ; 15(1)2022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-36668841

RESUMO

The high incidence of aflatoxins (AFs) in chocolates suggests the necessity to create a practical and cost-effective processing strategy for eliminating mycotoxins. The present study aimed to assess the adsorption abilities of activated charcoal (A. charcoal), yeast (Saccharomyces cerevisiae), and the probiotic Lactobacillus rhamnosus as AFs adsorbents in three forms-sole, di- and tri-mix-in phosphate-buffered saline (PBS) through an in vitro approach, simulated to mimic the conditions present in the gastrointestinal tract (GIT) based on pH, time and AFs concentration. In addition, the novel fortification of chocolate with A. charcoal, probiotic, and yeast (tri-mix adsorbents) was evaluated for its effects on the sensory properties. Using HPLC, 60 samples of dark, milk, bitter, couverture, powder, and wafer chocolates were examined for the presence of AFs. Results showed that all the examined samples contained AFs, with maximum concentrations of 2.32, 1.81, and 1.66 µg/kg for powder, milk, and dark chocolates, respectively. The combined treatment demonstrated the highest adsorption efficiency (96.8%) among all tested compounds. Scanning electron microscope (SEM) analysis revealed the tested adsorbents to be effective AF-binding agents. Moreover, the novel combination of tri-mix fortified chocolate had a minor cytotoxicity impact on the adsorptive abilities, with the highest binding at pH 6.8 for 4 h, in addition to inducing an insignificant effect on the sensory attributes of dark chocolate. Tri-mix is thus recommended in the manufacturing of dark chocolate in order to enhance the safety of the newly developed product.


Assuntos
Aflatoxinas , Cacau , Chocolate , Lacticaseibacillus rhamnosus , Chocolate/análise , Saccharomyces cerevisiae , Aflatoxinas/análise , Carvão Vegetal/farmacologia , Pós , Alérgenos
8.
Part Fibre Toxicol ; 17(1): 48, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33054855

RESUMO

BACKGROUND: Multi-walled carbon nanotubes can be divided into two general subtypes: tangled and straight. MWCNT-N (60 nm in diameter) and MWCNT-7 (80-90 nm in diameter) are straight-type MWCNTs, and similarly to asbestos, both are carcinogenic to the lung and pleura when administered to rats via the airway. Injection of straight-type MWCNTs into the peritoneal cavity also induces the development of mesothelioma, however, injection of tangled-type MWCNTs into the peritoneal cavity does not induce carcinogenesis. To investigate these effects in the lung we conducted a 2-year comparative study of the potential carcinogenicities of a straight-type MWCNT, MWCNT-A (approximately 150 nm in diameter), and a tangled-type MWCNT, MWCNT-B (7.4 nm in diameter) after administration into the rat lung. Crocidolite asbestos was used as the reference material, and rats administered vehicle were used as the controls. Test materials were administered by intra-Tracheal Intra-Pulmonary Spraying (TIPS) once a week over a 7 week period (8 administrations from day 1 to day 50), followed by a 2-year observation period without further treatment. Rats were administered total doses of 0.5 or 1.0 mg MWCNT-A and MWCNT-B or 1.0 mg asbestos. RESULTS: There was no difference in survival between any of the groups. The rats administered MWCNT-A or asbestos did not have a significant increase in bronchiolo-alveolar hyperplasia or tumors in the lung. However, the rats administered MWCNT-B did have significantly elevated incidences of bronchiolo-alveolar hyperplasia and tumors in the lung: the incidence of bronchiolo-alveolar hyperplasia was 0/20, 6/20, and 9/20 in the vehicle, 0.5 mg MWCNT-B, and 1.0 mg MWCNT-B groups, respectively, and the incidence of adenoma and adenocarcinoma combined was 1/19, 5/20, and 7/20 in the vehicle, 0.5 mg MWCNT-B, and 1.0 mg MWCNT-B groups, respectively. Malignant pleural mesothelioma was not induced in any of the groups. CONCLUSIONS: The results of this initial study indicate that tangled-type MWCNT-B is carcinogenic to the rat lung when administered via the airway, and that straight-type MWCNT-A did not have higher carcinogenic potential in the rat lung than tangled-type MWCNT-B.


Assuntos
Poluentes Atmosféricos/toxicidade , Nanotubos de Carbono/toxicidade , Animais , Asbesto Crocidolita , Testes de Carcinogenicidade , Exposição por Inalação , Pulmão , Neoplasias Pulmonares , Mesotelioma , Ratos , Traqueia/efeitos dos fármacos
9.
Part Fibre Toxicol ; 16(1): 34, 2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477126

RESUMO

BACKGROUND: Potassium octatitanate fibers (K2O•8TiO2, POT fibers) are used as an asbestos substitute. Their physical characteristics suggest that respirable POT fibers are likely to be carcinogenic in the lung and pleura. However, previous 2-year inhalation studies reported that respired POT fibers had little or no carcinogenic potential. In the present study ten-week old male F344 rats were left untreated or were administered vehicle, 0.25 or 0.5 mg rutile-type nano TiO2 (r-nTiO2), 0.25 or 0.5 mg POT fibers, or 0.5 mg MWCNT-7 by intra-tracheal intra-pulmonary spraying (TIPS), and then observed for 2 years. RESULTS: There were no differences between the r-nTiO2 and control groups. The incidence of bronchiolo-alveolar cell hyperplasia was significantly increased in the groups treated with 0.50 mg POT and 0.50 mg MWCNT-7. The overall incidence of lung tumors, however, was not increased in either the POT or MWCNT-7 treated groups. Notably, the carcinomas that developed in the POT and MWCNT-7 treated rats were accompanied by proliferative fibrous connective tissue while the carcinomas that developed in the untreated rats and the r-nTiO2 treated rats were not (carcinomas did not develop in the vehicle control rats). In addition, the carcinoma that developed in the rat treated with 0.25 mg POT was a squamous cell carcinoma, a tumor that develops spontaneously in about 1 per 1700 rats. The incidence of mesothelial cell hyperplasia was 4/17, 7/16, and 10/14 and the incidence of malignant mesothelioma was 3/17, 1/16, and 2/14 in the 0.25 mg POT, 0.5 mg POT, and MWCNT-7 treated groups, respectively. Neither mesothelial cell hyperplasia nor mesothelioma developed in control rats or the rats treated with r-nTiO2. Since the incidence of spontaneously occurring malignant mesothelioma in rats is extremely low, approximately 1 per 1000 animals (Japan Bioassay Research Center [JBRC] historical control data), the development of multiple malignant mesotheliomas in the POT and MWCNT-7 treated groups was biologically significant. CONCLUSION: The incidence of pleural mesotheliomas in male F344 rats administered POT fibers and MWCNT-7 was significantly higher than the JBRC historical control data, indicating that the incidence of pleural mesothelioma in the groups administered POT fibers and MWCNT-7 fibers via the airway using TIPS was biologically significant. The incidence of type II epithelial cell hyperplasia and the histology of the carcinomas that developed in the POT treated rats also indicates that respirable POT fibers are highly likely to be carcinogenic in the lungs of male F344 rats.


Assuntos
Carcinógenos/toxicidade , Neoplasias Pulmonares/induzido quimicamente , Pulmão/efeitos dos fármacos , Mesotelioma/induzido quimicamente , Pleura/efeitos dos fármacos , Titânio/toxicidade , Animais , Carcinógenos/química , Carcinógenos/farmacocinética , Exposição por Inalação , Pulmão/patologia , Neoplasias Pulmonares/patologia , Masculino , Mesotelioma/patologia , Mesotelioma Maligno , Fibras Minerais , Pleura/patologia , Ratos Endogâmicos F344 , Propriedades de Superfície , Distribuição Tecidual , Titânio/química , Titânio/farmacocinética
10.
Cancer Sci ; 110(8): 2485-2492, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31265162

RESUMO

Multi-walled carbon nanotube-7 (MWCNT-7) fibers are biopersistent and have a structure similar to asbestos. MWCNT-7 has been shown to induce malignant mesothelioma when administered by intrascrotal or intraperitoneal injection in rats and mice, and an inhalation study demonstrated that rats exposed to respirable MWCNT-7 developed lung tumors. MWCNT-N, which is similar to MWCNT-7, was shown to induce both lung tumors and malignant mesothelioma in rats when administered by trans-tracheal intrapulmonary spraying (TIPS). The present study was performed to investigate the carcinogenicity of MWCNT-7 when administered by the TIPS method. Ten-week-old male F344/Crj rats were divided into 3 groups and administered 0.5 mL vehicle, 0.250 µg/mL MWCNT-7 or 0.250 µg/mL crocidolite once a week for 12 weeks (total doses of 1.5 mg/rat) and then observed for up to 104 weeks. Rats in the MWCNT-7 group began to die from pathologies associated with the development of malignant mesothelioma 35 weeks after the final TIPS administration. Overall, the incidence of malignant mesothelioma in the MWCNT-7 group was significantly higher than in the vehicle or crocidolite groups.


Assuntos
Neoplasias Pulmonares/induzido quimicamente , Pulmão/efeitos dos fármacos , Mesotelioma/induzido quimicamente , Nanotubos de Carbono/efeitos adversos , Neoplasias Pleurais/induzido quimicamente , Animais , Asbesto Crocidolita/efeitos adversos , Injeções Intraperitoneais/métodos , Neoplasias Pulmonares/patologia , Masculino , Mesotelioma/patologia , Mesotelioma Maligno , Neoplasias Pleurais/patologia , Ratos , Ratos Endogâmicos F344 , Traqueia/efeitos dos fármacos , Traqueia/patologia
11.
Arch Toxicol ; 93(4): 909-920, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30759267

RESUMO

Potassium octatitanate (K2O·8TiO2, POT) fibers are used as an alternative to asbestos. Their shape and biopersistence suggest that they are possibly carcinogenic. However, inhalation studies have shown that respired POT fibers have little carcinogenic potential. We conducted a short-term study in which we administered POT fibers, and anatase and rutile titanium dioxide nanoparticles (a-nTiO2, r-nTiO2) to rats using intra-tracheal intra-pulmonary spraying (TIPS). We found that similarly to other materials, POT fibers were more toxic than non-fibrous nanoparticles of the same chemical composition, indicating that the titanium dioxide composition of POT fibers does not appear to account for their lack of carcinogenicity. The present report describes the results of the 3-week and 52-week interim killing of our current 2-year study of POT fibers, with MWCNT-7 as a positive control and r-nTiO2 as a non-fibrous titanium dioxide control. Male F344 rats were administered 0.5 ml vehicle, 62.5 µg/ml and 125 µg/ml r-nTiO2 and POT fibers, and 125 µg/ml MWCNT-7 by TIPS every other day for 2 weeks (eight doses: total doses of 0.25 and 0.50 mg/rat). At 1 year, POT and MWCNT-7 fibers induced significant increases in alveolar macrophage number, granulation tissue in the lung, bronchiolo-alveolar cell hyperplasia and thickening of the alveolar wall, and pulmonary 8-OHdG levels. The 0.5 mg POT- and the MWCNT-7-treated groups also had increased visceral and parietal pleura thickness, increased mesothelial cell PCNA labeling indices, and a few areas of visceral mesothelial cell hyperplasia. In contrast, in the r-nTiO2-treated groups, none of the measured parameters were different from the controls.


Assuntos
Pulmão/efeitos dos fármacos , Nanopartículas/toxicidade , Nanotubos de Carbono/toxicidade , Pleura/efeitos dos fármacos , Titânio/toxicidade , Animais , Exposição por Inalação , Pulmão/metabolismo , Pulmão/patologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/ultraestrutura , Masculino , Tamanho do Órgão/efeitos dos fármacos , Pleura/metabolismo , Pleura/patologia , Ratos Endogâmicos F344 , Distribuição Tecidual , Titânio/farmacocinética
12.
Arch Toxicol ; 93(1): 49-59, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30341734

RESUMO

Very little is known about the in vivo toxicity of inhaled double-walled carbon nanotubes (DWCNTs). In the present study, we compared the pulmonary toxicity of DWCNT to MWCNT-7, a well-known multi-walled carbon nanotube. Rats were divided into six groups: untreated, vehicle, low-dose DWCNT, high-dose DWCNT, low-dose MWCNT-7, and high-dose MWCNT-7. The test materials were administered by intra-tracheal intra-pulmonary spraying (TIPS) every other day for 15 days: the low-dose and high-dose groups were administered final total doses of 0.25 and 0.50 mg/rat of the test material. The animals were sacrificed 1 and 6 weeks after the final TIPS administration. Six weeks after the final TIPS administration, rats administered MWCNT-7 had high levels of macrophage infiltration into the lung with dense alveolar wall fibrous thickening throughout the lung; significant elevation of lactate dehydrogenase activity, alkaline phosphatase activity, and total protein concentration in the bronchioalveolar lavage fluid; an increase in the pulmonary cell PCNA index; slightly elevated levels of 8-OHdG DNA adducts in lung tissue DNA; a small but significant increase in protein concentration in the pleural cavity lavage fluid and an increase in the visceral mesothelial cell PCNA index. None of these parameters was increased in rats administered DWCNT. The primary lesion in rats administered DWCNT was scattered formation of granulation tissue containing internalized DWCNT fibers. Our data indicate that DWCNT has lower pulmonary and pleural toxicity than MWCNT-7.


Assuntos
Exposição por Inalação , Nanotubos de Carbono/toxicidade , Alvéolos Pulmonares/patologia , Fosfatase Alcalina/análise , Animais , Líquido da Lavagem Broncoalveolar/química , Quimiocinas/análise , Adutos de DNA/análise , Fibrose , L-Lactato Desidrogenase/análise , Macrófagos Alveolares , Masculino , Ratos Endogâmicos F344 , Testes de Toxicidade
13.
Chem Res Toxicol ; 31(10): 1025-1031, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30212183

RESUMO

Translocation of multiwalled carbon nanotubes (MWCNTs) from the lung to the pleural cavity, deposition of the fibers in the pleural tissue, induction of pleural fibrosis, and mesothelial proliferation have been found in rodents administered MWCNTs by different pulmonary exposure methods. However, whether the translocation and deposition and the subsequent pleural inflammation are associated with the pleural lesions is unclear. In the present study, male F344 rats were given 250 µg of two types of MWCNTs, with crocidolite as a positive control, 2 times/week for 4 weeks by intratracheal spraying. At 24 h and at 3 months after the last spraying, the rats were sacrificed for histological examination of the lung and chest wall; pleural cavity lavage was also collected at sacrifice for observation of pleural inflammatory reactions. The results indicated that intratracheally sprayed MWCNTs, like crocidolite fibers, translocated into the pleural cavity, deposited in the pleura, and induced persistent infiltration of immune cells into the pleural cavity, persistent pleural fibrosis, and mesothelial proliferation. The number of MWCNT fibers detected in the pleural cavity lavage was parallel to the number of infiltrating immune cells, which were mainly composed of macrophages. Analysis of cytokines in the fluids of the pleural cavity lavages by suspension array indicated that levels of IL-2, IL-18, and IP-10 were significantly increased both at 24 h and at 3 months after the last spraying. In vitro proliferation assays revealed that a mixture of IL-2, IL-18, and IP-10, but not any of these cytokines alone, promoted cell proliferation of human fibroblasts and mesothelial cells. These results suggest that translocated and deposited MWCNTs induce subsequent pleural inflammation and that increased IL-2, IL-18, and IP-10 synergistically promote the development of pleural fibrosis and mesothelial proliferation.


Assuntos
Inflamação , Nanotubos de Carbono/toxicidade , Pleura/efeitos dos fármacos , Animais , Asbesto Crocidolita/toxicidade , Líquido da Lavagem Broncoalveolar/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Citocinas/análise , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Fibrose , Humanos , Inflamação/etiologia , Masculino , Nanotubos de Carbono/química , Pleura/metabolismo , Pleura/patologia , Ratos , Ratos Endogâmicos F344
14.
Cancer Sci ; 109(7): 2164-2177, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29774637

RESUMO

Potassium octatitanate fibers (K2 O·8TiO2 , POT fibers) are widely used as an alternative to asbestos. We investigated the pulmonary and pleural toxicity of POT fibers with reference to 2 non-fibrous titanium dioxide nanoparticles (nTiO2 ), photoreactive anatase (a-nTiO2 ) and inert rutile (r-nTiO2 ). Ten-week-old male F344 rats were given 0.5 mL of 250 µg/mL suspensions of POT fibers, a-nTiO2 , or r-nTiO2 , 8 times (1 mg/rat) over a 15-day period by trans-tracheal intrapulmonary spraying (TIPS). Rats were killed at 6 hours and at 4 weeks after the last TIPS dose. Alveolar macrophages were significantly increased in all treatment groups at 6 hours and at 4 weeks. At week 4, a-nTiO2 and r-nTiO2 were largely cleared from the lung whereas a major fraction of POT fibers were not cleared. In the bronchoalveolar lavage, alkaline phosphatase activity was elevated in all treatment groups, and lactate dehydrogenase (LDH) activity was elevated in the a-nTiO2 and POT groups. In lung tissue, oxidative stress index and proliferating cell nuclear antigen (PCNA) index were elevated in the a-nTiO2 and POT groups, and there was a significant elevation in C-C motif chemokine ligand 2 (CCL2) mRNA and protein in the POT group. In pleural cavity lavage, total protein was elevated in all 3 treatment groups, and LDH activity was elevated in the a-nTiO2 and POT groups. Importantly, the PCNA index of the visceral mesothelium was increased in the POT group. Overall, POT fibers had greater biopersistence, induced higher expression of CCL2, and provoked a stronger tissue response than a-nTiO2 or r-nTiO2 .


Assuntos
Pulmão/efeitos dos fármacos , Pulmão/patologia , Pleura/efeitos dos fármacos , Pleura/patologia , Titânio/toxicidade , Animais , Macrófagos Alveolares/efeitos dos fármacos , Masculino , Fibras Minerais/toxicidade , Ratos , Ratos Endogâmicos F344
15.
Environ Sci Pollut Res Int ; 23(2): 1664-70, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26385855

RESUMO

Cadmium (Cd) is one of the naturally occurring heavy metals having adverse effects, while vitamin C (L-ascorbic acid) is an essential micronutrient for fish, which can attenuate tissue damage owing to its chain-breaking antioxidant and free radical scavenger properties. The adult Nile tilapia fish were exposed to Cd at 5 mg/l with and without vitamin C (500 mg/kg diet) for 45 days in addition to negative and positive controls fed with the basal diet and basal diet supplemented with vitamin C, respectively. Hepatic relative mRNA expression of genes involved in antioxidant function, metallothionein (MT), glutathione S-transferase (GST-α1), and glutathione peroxidase (GPx1), was assessed using real-time reverse transcription polymerase chain reaction (RT-PCR). Hepatic architecture was also histopathologically examined. Tilapia exposed to Cd exhibited upregulated antioxidants' gene transcript levels, GST-⍺1, GPx1, and MT by 6.10-, 4.60-, and 4.29-fold, respectively. Histopathologically, Cd caused severe hepatic changes of multifocal hepatocellular and pancreatic acinar necrosis, and lytic hepatocytes infiltrated with eosinophilic granular cells. Co-treatment of Cd-exposed fish with vitamin C overexpressed antioxidant enzyme-related genes, GST-⍺1 (16.26-fold) and GPx1 (18.68-fold), and maintained the expression of MT gene close to control (1.07-fold), averting the toxicopathic lesions induced by Cd. These results suggested that vitamin C has the potential to protect Nile tilapia from Cd hepatotoxicity via sustaining hepatic antioxidants' genes transcripts and normal histoarchitecture.


Assuntos
Antioxidantes/metabolismo , Ácido Ascórbico/farmacologia , Cádmio/toxicidade , Ciclídeos/metabolismo , Fígado/efeitos dos fármacos , Vitaminas/farmacologia , Animais , Ácido Ascórbico/metabolismo , Cádmio/metabolismo , Ciclídeos/genética , Suplementos Nutricionais , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Fígado/metabolismo , Metalotioneína/metabolismo , Metais Pesados/metabolismo , Vitaminas/metabolismo
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