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Toxicol Mech Methods ; : 1-16, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33467949


Smokeless tobacco products provide an alternative to cigarettes; however, smokeless tobacco is carcinogenic and harmful to human health. This study evaluated the toxicological effects of snus extracts and cigarette smoke total particulate matter (TPM) on human umbilical vein endothelial cells (HUVECs). Treated cells were examined for cell viability, reactive oxygen species (ROS), apoptosis, and inflammatory cytokines. Moreover, we explored the mechanism of programmed cell death induced by snus. The results showed that snus extracts significantly inhibited cell viability in a dose-dependent manner. ROS was significantly increased in treatment groups, and anti-oxidant treatment could not prevent snus extract-induced cell death. Snus extracts induced apoptosis, DNA damage, activation and cleavage of caspase-3 and caspase-8, pathway-related gene change, and interleukin (IL)-6 and IL-8 release in HUVECs. Snus extracts exposure may induce cytotoxicity, ROS generation, inflammatory cytokines release, and apoptosis or DNA damage through intrinsic and extrinsic pathways in HUVECs.

Toxicol Lett ; 316: 10-19, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31476341


Rapid risk assessment models for different types of cigarette smoke extract (CSE) exposure are critical to understanding the etiology of chronic obstructive pulmonary disease. The present study investigated inflammation of cultured tracheal tissues with CSE exposure. Rat trachea rings were isolated, cultured, then exposed to various concentrations of CSE from 3R4 F reference cigarettes for 4 h. Tissue/cellular morphology, ultrastructure, viability and damage, inflammatory cell infiltration, and inflammatory protein levels were measured and compared to untreated controls. Human bronchial epithelial cells (BEAS-2B) exposed to 0 or 300 µg/mL CSE were cocultured with macrophages to assess extent of mobilization and phagocytosis. Endotracheal epithelium cilia densities were significantly reduced with increasing CSE concentrations, while mucous membranes became increasingly disordered; both eventually disappeared. Macrophages became larger as the CSE concentration increased, with microvilli and extended pseudopodium covering their surface, and many primary and secondary lysosomes present in the cytoplasm. Inflammatory cell infiltration also increased with increasing CSE dose, as did intracellular adhesion molecule-1(ICAM-1), interleukin-6(IL-6). The method described here may be useful to qualitatively characterized the effects of the compound under study. Then, we use BEAS-2B cell line system to strength the observation made in the cultured tissues. Probably, an approach to integrate results from both experiments will facilitate its application. These results demonstrate that cultured rat tracheal rings have a whole-tissue structure that undergoes inflammatory processes similar to in vivo tissues upon CSE exposure.

Células Epiteliais/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/etiologia , Fumaça/efeitos adversos , Fumar/efeitos adversos , Tabaco/efeitos adversos , Traqueia/efeitos dos fármacos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Humanos , Mediadores da Inflamação/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-6/metabolismo , Macrófagos/metabolismo , Macrófagos/ultraestrutura , Masculino , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia , Ratos Sprague-Dawley , Medição de Risco , Fatores de Tempo , Técnicas de Cultura de Tecidos , Traqueia/metabolismo , Traqueia/ultraestrutura
Toxicol Mech Methods ; 29(7): 499-510, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31050318


The tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is classified as a Group 1 human carcinogen. It is metabolically activated by P450 enzymes to intermediate methylate and pyridyloxobutylate DNA, resulting in the formation of DNA adduct that is critical for the carcinogenicity of NNK. To directly and objectively examine the DNA adduct formation profiles without the complexity of factors in vivo, in the present study, five kinds of methyl DNA adducts were first identified in the incubation model of NNK established with human lung epithelial cells (BEAS-2B). The level of methyl DNA adducts and metabolites of NNK were quantitatively analyzed, respectively. With the increase of exposure time and dose, the level of methyl DNA adducts and metabolites increased. Furthermore, with the changes of the activity of P450 enzymes, which is the main enzyme regulating the α-hydroxylation of NNK, we found the levels of both methyl adducts and metabolites formed via α-hydroxylation in experimental groups showed the same trend compared with those in control group, while the metabolites formed via other pathways changed in the opposite trend. The result proves that the methyl adducts induced by NNK generate via α-hydroxylation pathway in BEAS-2B cells.

Carcinógenos/toxicidade , Adutos de DNA/metabolismo , Metilação de DNA/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Nitrosaminas/toxicidade , Carcinógenos/metabolismo , Técnicas de Cultura de Células , Linhagem Celular , Sistema Enzimático do Citocromo P-450 , Relação Dose-Resposta a Droga , Células Epiteliais/enzimologia , Células Epiteliais/metabolismo , Humanos , Hidroxilação , Pulmão/enzimologia , Pulmão/metabolismo , Nitrosaminas/metabolismo
J Pharm Biomed Anal ; 172: 50-57, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31026772


Two novel sorbents based on polydopamine (PDA)-coated magnetic graphite oxide-metal organic frameworks nanoparticles [Cu(L-mal)(bpy)]·H2O (MGO-CuLBH) and [Cu(D-mal)(bpy)]·H2O (MGO-CuDBH) possessing of both magnetic property and excellent enantioselective ability were prepared and characterized. Solutions of racemic propranolol hydrochloride (Rac-PRO) were chosen to investigate the enantioselective performance of MGO-CuLBH and MGO-CuDBH by dispersive magnetic nanoparticle solid phase extraction (d-MNSPE). The results showed that the nanocomposites have excellent enantioselectivity to PROs with enantiomeric excess (ee) values reaching up to 98%. The entire process with PROs by the d-MNSPE method was fast, convenient and the collected composites could be easily recycled. Multi-stage operations using MGO-CuLBH and MGO-CuDBH were scaled up to obtain milligram quantities of R-propranolol hydrochloride (R-PRO) and S-propranolol hydrochloride (S-PRO). Furthermore, on the basis of the successful preparations, the differences in the cytotoxicity of Rac-PRO, R-PRO and S-PRO on A549 cells in vitro were all evaluated.

Composição de Medicamentos/métodos , Estruturas Metalorgânicas/química , Nanocompostos/química , Propranolol/química , Extração em Fase Sólida/métodos , Células A549 , Humanos , Magnetismo , Propranolol/toxicidade , Estereoisomerismo , Testes de Toxicidade
Toxins (Basel) ; 10(11)2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-30380714


The development of Dinophysis populations, producers of diarrhetic shellfish toxins, has been attributed to both abiotic (e.g., water column stratification) and biotic (prey availability) factors. An important process to consider is mixotrophy of the Dinophysis species, which is an intensive feeding of the Mesodinium species for nutrients and a benefit from kleptochloroplasts. During the feeding process, the nutritional status in the environment changes due to the preference of Mesodinium and/or Dinophysis for different nutrients, prey cell debris generated by sloppy feeding, and their degradation by micro-organisms changes. However, there is little knowledge about the role of the bacterial community during the co-occurrence of Mesodinium and Dinophysis and how they directly or indirectly interact with the mixotrophs. In this study, laboratory experiments were performed to characterize the environmental changes including those of the prey present, the bacterial communities, and the ambient dissolved nutrients during the co-occurrence of Mesodinium rubrum and Dinophysis acuminata. The results showed that, during the incubation of the ciliate prey Mesodinium with its predator Dinophysis, available dissolved nitrogen significantly shifted from nitrate to ammonium especially when the population of M. rubrum decayed. Growth phases of Dinophysis and Mesodinium greatly affected the structure and composition of the bacterial community. These changes could be mainly explained by both the changes of the nutrient status and the activity of Dinophysis cells. Dinophysis feeding activity also accelerated the decline of M. rubrum and contamination of cultures with okadaic acid, dinophysistoxin-1, and pectenotoxin-2, but their influence on the prokaryotic communities was limited to the rare taxa (<0.1%) fraction. This suggests that the interaction between D. acuminata and bacteria is species-specific and takes place intracellularly or in the phycosphere. Moreover, a majority of the dominant bacterial taxa in our cultures may also exhibit a metabolic flexibility and, thus, be unaffected taxonomically by changes within the Mesodinium-Dinophysis culture system.

Bactérias/classificação , Cilióforos/metabolismo , Dinoflagelados/metabolismo , Dinoflagelados/fisiologia , Especificidade da Espécie
Toxicon ; 100: 67-72, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25895426


T-2 toxin is one form of trichothecenes, which contaminate crops and feedstuff commonly, and has a wide variety of toxic effects in human and animals, but little is known regarding its role on reproductive function and puberty development. Previous studies have reported that reproductive capacity is attained at puberty triggered by gonadotropin-releasing hormone (GnRH) pulse secretion, and kisspeptins/GPR54 signaling pathway play a central role in the activation of GnRH neurons. For our study, T-2 toxin was tested for its effects on the secretion of GnRH in GT1-7 cells, an immortalized hypothalamic neuron cell line, which could synthesize and secrete GnRH. GT1-7 cells were treated with low doses of T-2 toxin in dose-response assays, with and without kisspeptins, and the levels of GnRH were quantified in each treatment. Furthermore, western blot analysis was used to detect the proteins expression in kisspeptins/GPR54 signaling pathway. The present study demonstrated that low dose T-2 toxin stimulate GnRH secretion and alter the expression of associated proteins in GT1-7 cells in vitro, and the activation of GT1-7 cells response to T- 2 toxin was increased after pretreatment with kisspeptins.

Toxina T-2/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/metabolismo , Kisspeptinas/farmacologia , Camundongos , Biossíntese de Proteínas/efeitos dos fármacos , Reprodução/efeitos dos fármacos