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1.
Braz. j. biol ; 84: e256905, 2024. tab
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1360212

ABSTRACT

Abstract During present study, the copper (Cu) mediated oxidative stress was measured that induced DNA damage by concentrating in the tissues of fish, Catla catla (14.45±1.24g; 84.68±1.45mm) (Hamilton,1822). Fish fingerlings were retained in 5 groups for 14, 28, 42, 56, 70 and 84 days of the exposure period. They were treated with 2/3, 1/3, 1/4 and 1/5 (T1-T4) of 96h lethal concentration of copper. Controls were run along with all the treatments for the same durations. A significant (p < 0.05) dose and time dependent concentration of Cu was observed in the gills, liver, kidney, muscles, and brain of C. catla. Among organs, the liver showed a significantly higher concentration of Cu followed by gills, kidney, brain, and muscles. Copper accumulation in these organs caused a significant variation in the activities of enzymes viz. superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD). The SOD activity varied significantly in response to the exposure time of Cu as 56 > 70 > 42 > 84 > 28 > 14 days while CAT activity exhibited an inverse relationship with the increase in Cu concentration. POD activity showed a significant rise with an increase in Cu exposure duration. Comet assay exhibited significant DNA damage in the peripheral erythrocytes of Cu exposed C. catla. Among four exposure concentrations, 2/3rd of LC50 (T1) caused significantly higher damage to the nuclei compared to control. Increased POD and SOD activity, as well as a decrease in CAT activity in response to Cu, demonstrates the involvement of a protective mechanism against reactive oxygen species (ROS), whereas increased ROS resulted in higher DNA damage. These above-mentioned molecular markers can be efficiently used for the biomonitoring of aquatic environments and conservation of edible fish fauna.


Resumo Durante o presente estudo, o estresse oxidativo mediado pelo cobre (Cu) foi medido que induziu danos ao DNA por concentração nos tecidos de peixes, Catla catla (14,45 ± 1,24g; 84,68 ± 1,45mm) (Hamilton, 1822). Os alevinos foram retidos em 5 grupos por 14, 28, 42, 56, 70 e 84 dias do período de exposição. Eles foram tratados com 2/3, 1/3, 1/4 e 1/5 (T1-T4) de 96h de concentração letal de cobre. Os controles foram executados junto com todos os tratamentos para as mesmas durações. Uma significativa (p <0,05) concentração dependente do tempo e da dose de Cu foi observada nas brânquias, fígado, rim, músculos e cérebro de C. catla. Entre os órgãos, o fígado apresentou uma concentração significativamente maior de cobre, seguido por guelras, rins, cérebro e músculos. O acúmulo de cobre nesses órgãos causou uma variação significativa nas atividades das enzimas viz. superóxido dismutase (SOD), catalase (CAT) e peroxidase (POD). A atividade de SOD variou significativamente em resposta ao tempo de exposição de Cu como 56> 70> 42> 84> 28> 14 dias, enquanto a atividade de CAT exibiu uma relação inversa com o aumento na concentração de Cu. A atividade POD mostrou um aumento significativo com um aumento na duração da exposição ao Cu. O ensaio do cometa exibiu dano significativo ao DNA induzido por Cu nos eritrócitos periféricos de C. catla. Entre as quatro concentrações de exposição, 2/3 do LC50 (T1) causou danos significativamente maiores aos núcleos em comparação com o controle. O aumento da atividade de POD e SOD, bem como uma diminuição na atividade de CAT em resposta ao Cu, demonstra o envolvimento de um mecanismo protetor contra espécies reativas de oxigênio (ROS), enquanto o aumento de ROS resultou em maior dano ao DNA. Esses marcadores moleculares mencionados acima podem ser usados ​​de forma eficiente para o biomonitoramento de ambientes aquáticos e conservação da ictiofauna comestível.

2.
Braz. j. biol ; 83: e240118, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1278559

ABSTRACT

Abstract For many centuries human populations have been suffering and trying to fight with disease-bearing mosquitoes. Emerging and reemerging diseases such as Dengue, Zika, and Chikungunya affect billions of people around the world and recently has been appealing to control with chemical pesticides. Malathion (MT) is one of the main pesticides used against mosquitoes, the vectors of these diseases. This study aimed to assess cytotoxicity and mutagenicity of the malathion for the bioindicator Allium cepa L. using a multivariate and integrative approach. Moreover, an appendix table was compiled with all available literature of insecticides assessed by the Allium cepa system to support our discussion. Exposures during 48h to 0.5 mg mL-1 and 1.0 mg mL-1 MT were compared to the negative control (distilled water) and positive control (MMS solution at 10 mg L-1). The presence of chromosomal aberrations, micronuclei frequency, and mitotic index abnormalities was evaluated. Anaphase bridges were the alterations with higher incidence and presented a significantly elevated rate in the concentration of 0.5 mg mL-1, including when compared to the positive control. The integrative discriminant analysis summarizes that MT in assessed concentrations presented effects like the positive control, corroborating its potential of toxicity to DNA. Therefore, it is concluded that MT in its pure composition and in realistic concentrations used, has genotoxic potential in the biological assessment of A. cepa cells. The multivariate integrative analysis was fundamental to show a whole response of all data, providing a global view of the effect of MT on DNA.


Resumo Por muitos séculos, as populações humanas sofrem e tentam combater os mosquitos transmissores de doenças. Doenças emergentes e reemergentes como Dengue, Zika e Chikungunya afetam bilhões de pessoas em todo o mundo e, recentemente, vem apelando ao controle com pesticidas químicos. O Malation (MT) é um dos principais pesticidas usados ​​contra mosquitos, vetores dessas doenças. O objetivo deste estudo foi avaliar a citotoxicidade e a mutagenicidade do MT para o bioindicador Allium cepa L. usando uma abordagem multivariada e integrativa. Além disso, uma tabela suplementar foi compilada com toda a literatura disponível de inseticidas avaliada pelo sistema Allium cepa para apoiar nossa discussão. Exposições ao MT durante 48h a 0,5 mg mL-1 e 1,0 mg mL-1 foram comparadas a um controle negativo (água destilada) e um controle positivo (10 mg L-1 de MMS). Foram avaliadas a presença de aberrações cromossômicas, frequência de micronúcleos e anormalidades no índice mitótico. As pontes anafásicas foram as alterações com maior incidência e apresentaram uma taxa significativamente elevada na concentração de 0,5 mg mL-1, inclusive quando comparadas ao controle positivo. A análise discriminante integrativa resume que o MT nas concentrações avaliadas apresentou efeitos semelhantes ao controle positivo, corroborando seu potencial de toxicidade para o DNA. Portanto, conclui-se que o MT, em sua composição pura e nas concentrações realistas utilizadas, possui potencial genotóxico na avaliação biológica de células de A. cepa. A análise integrativa multivariada foi fundamental para mostrar uma resposta completa de todos os dados, fornecendo uma visão global do efeito da MT no DNA.


Subject(s)
Humans , Animals , Zika Virus , Zika Virus Infection , Insecticides/toxicity , DNA Damage , Chromosome Aberrations , Plant Roots , Onions , Mosquito Vectors , Malathion/toxicity , Mitotic Index
3.
Braz. j. biol ; 83: e244127, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1278526

ABSTRACT

Abstract Tiliroside is a glycosidic flavonoid present in many plants species including Helicteres velutina K. Schum (Malvaceae sensu lato), commonly known in Brazil as "pitó". This molecule has been shown to have many biological activities, however no study has been carried out to investigate the toxicity of this substance. The present work aimed to evaluate the possible cellular toxicity in silico, in vitro and ex-vivo of the kaempferol-3-O-β-D-(6"-E-p-coumaroyl) glucopyranoside (tiliroside), through chemical structure analysis, toxicity assessment and predictive bioactive properties, using human samples for in vitro and ex-vivo tests. The in silico analysis suggests that tiliroside exhibited great absorption index when penetrating biological membranes. In addition, it also displayed considerable potential for cellular protection against free radicals, and anticarcinogenic, antioxidant, antineoplastic, anti-inflammatory, anti-hemorrhagic and antithrombotic activities. The assessment of the hemolytic and genotoxic effects of tiliroside showed low hemolysis rates in red blood cells and absence of cellular toxicity in the oral mucosa cells. The data obtained indicate that this molecule could be a promising therapeutic approach as a possible new drug with biotechnological potential.


Resumo O tilirosídeo é um flavonóide glicosídico presente em muitas espécies de plantas, incluindo Helicteres velutina K. Schum (Malvaceae sensu lato), conhecida no Brasil como "pitó". Esta molécula mostrou ter muitas atividades biológicas, porém nenhum estudo foi realizado para investigar a toxicidade dessa substância. O presente trabalho teve como objetivo avaliar a possível toxicidade celular in silico, in vitro e ex-vivo do kaempferol-3-O-β-D- (6 "-Ep-coumaroil) glucopiranosídeo (tilirosídeo), por meio de análises de estrutura química, toxicidade avaliação e propriedades bioativas preditivas, utilizando amostras humanas para testes in vitro e ex-vivo. A análise in silico sugere que o tilirosídeo exibe bom índice de absorção para penetrar nas membranas biológicas. Além disso, apresentou considerável potencial de proteção celular contra os radicais livres e com atividades anticarcinogênica, antioxidante, antineoplásica, antiinflamatória, anti-hemorrágica e antitrombótica. A avaliação dos efeitos hemolíticos e genotóxicos do tilirosídeo mostrou baixas taxas de hemólise nas hemácias e ausência de toxicidade em células da mucosa oral. Os dados obtidos indicam que esta molécula pode possuir uma abordagem terapêutica promissora como uma possível nova droga com potencial biotecnológico.


Subject(s)
Humans , Plant Extracts , Kaempferols/toxicity , Flavonoids , Computer Simulation , Brazil
4.
Braz. dent. j ; 33(2): 33-43, Mar.-Apr. 2022. tab, graf
Article in English | LILACS-Express | LILACS, BBO | ID: biblio-1374625

ABSTRACT

Abstract An endodontic material must be minimally harmful to stem cells since they are essential, thanks to their capacity for cell proliferation, self-renewal, and differentiation. For this reason, in this in vitro study, the cell viability and the expression of genes involved in cell plasticity and differentiation were investigated in stem cells recovered from human dental pulp (hDPSCs) that were in contact with four endodontic materials (Endofill, MTA, Pulp Canal Sealer, and Sealer 26). The viability of HDPSCs was assessed by MTT and trypan blue exclusion assays. PCR evaluated cellular plasticity by determining the CD34, CD45, Nestin, CD105, Nanog, and OCT4 expressions. The effect on cell differentiation was determined by RT-PCR expression of the RUNX2, ALP, OC/BGLAP, and DMP1 genes. The data were analyzed using ANOVA with Bonferroni correction (p <0.05). Pulp Canal Sealer and Endofill decreased cell viability after 48 hours (p <0.001). MTA and Sealer 26 did not disrupt cell viability (p> 0.05). When cultivated in the presence of MTA and Sealer 26, hDPSCs expressed Nestin, CD105, NANOG, and OCT-4 and did not express CD34 and CD45. MTA and Sealer 26 interfered with DMP1, OC/BGLAP and RUNX2 expressions (p <0.05) but did not change ALP gene expression (p> 0.05). MTA and Sealer 26 showed biological compatibility in the presence of hDPSCs.


Resumo Um material endodôntico deve ser minimamente prejudicial às células-tronco, uma vez que essas células são extremamente importantes, devido à sua capacidade de proliferação, autorrenovação e diferenciação celular. Por esse motivo, a viabilidade celular e a expressão de genes envolvidos na plasticidade e diferenciação celular foram investigadas em células-tronco recuperadas de polpa dentária humana (HDPSCs) que estiveram em contato com quatro materiais endodônticos (Endofill, MTA, Pulp Canal Sealer e Sealer 26). A viabilidade das HDPSCs foi avaliada pelos ensaios MTT e de exclusão de azul de tripano. A plasticidade celular foi avaliada pela determinação das expressões dos genes CD34, CD45, Nestin, CD105, Nanog e OCT4 por PCR. O efeito na diferenciação celular foi determinado pela expressão dos genes RUNX2, ALP, OC/BGLAP e DMP1 por RT-PCR. Os dados foram analisados por ANOVA com correção de Bonferroni (p <0,05). Em comparação com o controle, Pulp Canal Sealer e Endofill diminuíram a viabilidade celular após 48 horas (p <0,001). MTA e Sealer 26 não interromperam a viabilidade celular (p> 0,05). Quando cultivado na presença de MTA e Sealer 26, as HDPSCs expressaram Nestin, CD105, NANOG e OCT-4 e não expressaram CD34 e CD45. MTA e Sealer 26 interferiram nas expressões de DMP1, OC / BGLAP e RUNX2 (p <0,05), mas não alteraram a expressão do gene ALP (p> 0,05). Sendo assim, MTA e Sealer 26 demonstraram compatibilidade biológica na presença de HDPSCs.

5.
Braz. J. Pharm. Sci. (Online) ; 58: e19261, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1374545

ABSTRACT

Abstract Persea americana Mill., belonging to the family Lauraceae, is noteworthy for the large amount of ethnopharmacological information in its regard, attributing to it many and varied medicinal properties. The tea and alcoholic extracts made from its leaves are used in folk medicine to treat various ailments. This study was designed to analyze the cytogenotoxicity and underlying chemistry of aqueous and hydroalcoholic extracts of avocado leaves, using the Allium cepa and micronucleus tests. The results obtained by applying the experimental models demonstrate that the extracts did not have a genotoxic effect at any of the concentrations analyzed, and even demonstrated a certain protective effect, possibly due to the presence of flavonoids and phenols, both of which are antioxidant substances. However, the extracts did present a cytotoxic effect. There were numerous karyorrhectic cells and those with nuclear alterations related to cell death. At the highest concentrations, it was possible to observe cytoplasmic alterations and binucleated cells. The extracts also caused a significant reduction in the number of cells undergoing division. These effects can be a response to the phytochemical agents present in the extracts. The results suggest that the extracts contain bioactive components that deserve further studies related to cancer therapies.

6.
Braz. J. Pharm. Sci. (Online) ; 58: e19221, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1374557

ABSTRACT

Abstract The purpose of the current work was to assess a possible role of cytochrome P450 1A2 (CYP1A2) and N-acetyltransferase 2 (NAT2) in the metabolic activation of 2,6-dimethylaniline (2,6-DMA) and also clarify the function of DNA repair in affecting the ultimate mutagenic potency. Two cell lines, nucleotide excision repair (NER)-deficient 5P3NAT2 and proficient 5P3NAT2R9 both expressing CYP1A2 and NAT2, were treated with 2,6-DMA for 48 h or its metabolites for 1 h. Cell survival determined by trypan blue exclusion and MTT assays, and 8-azaadenine-resistant mutants at the adenine phosphoribosyltransferase (aprt) gene locus were evaluated. 5P3NAT2 and 5P3NAT2R9 cells treated with 2,6-DMA and its metabolites showed a dose-dependent increase in cytotoxicity and mutant fraction; N-OH-2,6-DMA and 2,6-DMAP in serum-free α-minimal essential medium (MEM) are more potent than 2,6-DMA in complete MEM. 5P3NAT2 cells was more sensitive to the cytotoxic and mutagenic action than 5P3NAT2R9 cells. H2DCFH-DA assay showed dose-dependent ROS production under 2,6- DMAP treatment. These findings indicate that the genotoxic effects of 2,6-DMA are mediated by CYP1A2 activation via N-hydroxylation and the subsequent esterification by the phase II conjugation enzyme NAT2, and through the generation of ROS by hydroxylamine and/or aminophenol metabolites. NER status is also an important contributor.

7.
Article in Chinese | WPRIM | ID: wpr-920652

ABSTRACT

@#An HPLC pre-column derivatization detection method was established to detect and analyze the formaldehyde and acetaldehyde in polysorbate 80 and polysorbate 20 from different manufacturers.The effects of aldehyde and acetaldehyde on the aggregation of adalimumab under different conditions were monitored.Based on the control of genotoxic impurities and the influence on the stability of monoclonal antibody preparations, the control limits of the two chemicals were preliminarily obtained.2, 4-dinitrophenylhydrazine (2, 4-DNPH) was applied as the derivatization reagent in HPLC pre-column derivatization; acetonitrile and water were used as mobile phase to perform a gradient elution on a C8 (4.6 mm × 150 mm, 5 μm) chromatographic column.The detection wavelength was 360 nm, and the external standard method was used for quantification.Verification results showed that the method was suitable for the quantitative analysis of trace formaldehyde and acetaldehyde in polysorbate 80 and polysorbate 20 . The detection and analysis of formaldehyde or acetaldehyde in different batches of polysorbate 80 and polysorbate 20 from different manufacturers showed that the content of formaldehyde and acetaldehyde were quite different. The content of formaldehyde and acetaldehyde in polysorbate 80 were significantly higher than those of polysorbate 20. After monitoring the changes of adalimumab aggregates treated by formaldehyde and acetaldehyde by size exclusion chromatography (SEC), it was found that the effect of formaldehyde on adalimumab aggregation was significantly higher than that of acetaldehyde.According to the requirements of ICH M7 (International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use, M7: Assessment and Control of DNA Reactive (Mutagenic) Impurities in Pharmaceuticals to Limit Potential Carcinogenic Risk), the impurity limits of formaldehyde and acetaldehyde in polysorbate 80 and polysorbate 20 for monoclonal antibody preparations were calculated from the perspective of risk assessment.Combined with the influence on the aggregation stability of monoclonal antibodies, the preliminary limis for acetaldehyde and acetaldehyde were recommended to be ≤ 7 μg/g and ≤ 765 μg/g, respectively.

8.
Braz. arch. biol. technol ; 65: e22200784, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1364455

ABSTRACT

Abstract Nanoscale biomaterials are commonly used in a wide range of biomedical applications such as bone graft substitutes, gene delivery systems, and biologically active agents. On the other hand, the cytotoxic potential of these particles hasn't yet been studied comprehensively to understand whether or not they exert any negative impact on the cellular structures. Here, we undertook the synthesis of beta-tricalcium phosphate (ß-TCP) and biphasic tricalcium phosphate (BCP) nanoparticles (NPs) and determine their concentration-dependent toxic effects in human fetal osteoblastic (hFOB 1.19) cell line. Firstly, BCP and β-TCP were synthesized using a water-based precipitation technique and characterized by X-Ray Diffraction (XRD), Raman Spectroscopy, and Transmission Electron Microscopy (TEM). The cytological effects of β-TCP and BCP at different concentrations (0-640 ppm) were evaluated by using 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays. The total oxidative status (TOS) parameter was used for investigating oxidative stress potentials of the NPs. In addition, the study assessed the DNA damage product 8-hydroxy-2′-deoxyguanosine (8-Oxo-dG) level in hFOB 1.19 cell cultures. The results indicated that the β-TCP (above 320 ppm) and BCP (above 80 ppm) NPs exhibited cytotoxicity effects on high concentrations. It was also observed that the oxidative stress increased relatively as the concentrations of NPs increased, aligning with the cytotoxicity results. However, the NPs concentrations of 160 ppm and above increased the level of 8-OH-dG. Consequently, there is a need for more systematic in vivo and in vitro approaches to the toxic effects of both nanoparticles.

9.
Rev. peru. med. exp. salud publica ; 38(4): 587-594, oct.-dic. 2021. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1365918

ABSTRACT

RESUMEN Objetivos. Determinar el efecto genotóxico de la tartrazina en linfocitos de sangre periférica de Mus musculus BALB/c. Materiales y métodos. Se realizó un estudio experimental, a través de cinco grupos, con cinco ratones en cada uno. Se les registró el peso durante 17 semanas y, en la semana 15 se les administró suero fisiológico (control negativo), dicromato de potasio 25 mg/kg de peso corporal (pc) (control positivo) y tartrazina a dosis de 0,75 mg/kg pc, 7,5 mg/kg pc y 75 mg/kg pc, durante siete días, a excepción del control positivo que fue en dosis única. Luego, cada 24 h se obtuvo una muestra de sangre periférica de la cola y se realizó el frotis, secado y coloración. Posteriormente, se realizó el conteo de 1000 linfocitos por muestra de cada ratón, en todos los tratamientos. Resultados. Los tres tratamientos con tartrazina no causaron diferencias significativas en el peso de ratones a la semana 15, pero sí produjeron diferencias significativas en la frecuencia de linfocitos micronucleados, siendo el tratamiento con tartrazina de 75 mg/kg pc el de mayor efecto genotóxico, induciendo un promedio de 1,63 ± 0,08 linfocitos micronucleados, comparado con el control positivo que generó un promedio de 1,42 ± 0,08 linfocitos micronucleados. Conclusiones. La tartrazina produjo un efecto genotóxico, incrementando el número de linfocitos micronucleados, a dosis de 0,75; 7,5 y 75 mg/kg pc y no afecta el peso corporal durante siete días de administración en M. musculus BALB/c.


ABSTRACT Objectives. To determine the genotoxic effect of tartrazine on peripheral blood lymphocytes of BALB/c Mus musculus. Materials and methods. An experimental study was carried out using five groups, with five mice in each group. Their weight was registered for 17 weeks, and at week 15 they were administered physiological saline solution (negative control), potassium dichromate at 25 mg/kg body weight (bw) (positive control) and tartrazine at doses of 0.75 mg/kg bw, 7.5 mg/kg bw and 75 mg/kg bw, for seven days, with the exception of the positive control which was a single dose. Then, every 24 hours, a peripheral blood sample was obtained from the tail, which was then smeared, dried and stained. Subsequently, 1000 lymphocytes were counted for each sample from each mouse, for all treatment groups. Results. The three tartrazine treatments did not cause significant differences in the weight of mice at week 15, but did produce significant differences in the frequency of micronucleated lymphocytes, with the 75 mg/kg bw tartrazine treatment having the greatest genotoxic effect, inducing an average of 1.63 ± 0.08 micronucleated lymphocytes, compared to the positive control which obtained an average of 1.42 ± 0.08 micronucleated lymphocytes. Conclusions. Tartrazine produced a genotoxic effect, increasing the number of micronucleated lymphocytes, at doses of 0.75; 7.5 and 75 mg/kg bw and did not affect body weight during seven days of administration to BALB/c M. musculus.

10.
Article in English | LILACS-Express | LILACS | ID: biblio-1148222

ABSTRACT

This study aimed to evaluate the in silico, in vitro, and ex-vivo toxicity of vitexin, the flavonoid 5,7,4'- trihydroxyflavone-8-C-ß-glucopyranoside from Waltheria viscosissima. The chemical structure and predicted bioactive properties were also in silico analyzed. The in vitro and ex-vivo assays were performed according to the Ethics Code of the World Medical Association and were approved by the Ethics Committee of University Center of Patos (protocol number: 3.621.284). In silico analysis suggested that the molecule presents good oral bioavailability and good absorption; penetrating biological membranes. The toxicity tests revealed the potential effectiveness of the molecule in cellular protection against free radicals, in addition to possible antimutagenic, anticarcinogenic, antioxidant, antineoplastic, anti-inflammatory, anti-hemorrhagic and apoptosis agonist activity. Hemolytic and genotoxic assessment detected low hemolysis rates in human red blood cells and no cellular toxicity against oral mucosa cells. The data suggest that vitexin is a safe molecule for possible therapeutic application and its toxicity profile indicates viability for future studies.

11.
Article in Chinese | WPRIM | ID: wpr-882219

ABSTRACT

Objective:To establish a comet test method for detection of genotoxicity of three reference chemicals in rat liver cells. Methods:6-10 week old Sprague Dawley rats were randomly divided into 4 groups, with normal saline (0.9% NaCl solution) as negative control group. Animals in three test groups were treated, respectively, with ethyl methanesulfonate (EMS) 200 mg/kg, N-methyl-N-nitrosourea (MNU) 50 mg/kg, and D-mannitol 2 000 mg/kg. There were 10 animals in each group, 5 males and 5 females. The animals received two times (21 h interval) of test compounds through intragastric administration, and their clinical symptoms and body weight changes were recorded during the experiment. The rats were sacrificed 3 h after the last exposure. The liver was weighed, then used to prepare single-cell suspensions for the alkaline comet test which determines the average tail DNA content percentage (DNA%) of hepatocytes and other comet indicators. Results:(1) D-mannitol, EMS and MNU did not show significant toxicity in the whole animal. (2) The mean values of tail DNA content percentage (DNA%) of rat hepatocytes in EMS [(60.07±24.69)%] and MNU [(41.66±22.35)%] groups were higher than that in the negative control group [(2.32±1.39)%] and the difference was statistically significant (P<0.05). The difference between D-mannitol group [(3.06±3.30)%] and the negative control group was not significant (P>0.05). Conclusion:This laboratory has established a comet test method using hepatocytes from treated rats. Among three testing chemicals, EMS and MNU have displayed genotoxicity by this assay, but no genotoxicity was observed in D-mannitol treated animals.

12.
Braz. arch. biol. technol ; 64: e21200093, 2021. tab, graf
Article in English | LILACS | ID: biblio-1153294

ABSTRACT

HIGHLIGHTS Sodium arsenite can cause neoplastic transformation in cells. Curcumin reduced cell viability and increased LDH activity in transformed Balb/c 3T3 cells. Curcumin caused DNA damage in transformed Balb/c 3T3 cells. Curcumin may play a protective role in sodium arsenite-induced toxicity.


Abstract Arsenic is a toxic substance that spreads widely around the environment and accumulates as metalloid in the earth's crust. Arsenic and its derivatives are found in drinking water, nutrients, soil, and air. Exposure to arsenic is associated with lung, blood, skin cancer and various lesions. Curcumin is a polyphenolic compound derived from Curcuma longa (turmeric) rhizome and is one of the main curcuminoids. Curcumin is known to be antioxidant, antibacterial, anti-inflammatory, analgesic effects. This study aimed to investigate the potential of sodium arsenite to transform embryonic fibroblast cells and to evaluate the cytotoxic and genotoxic effects of curcumin in neoplastic transformed cells. Neoplastic cells transformation was induced by sodium arsenite in Balb/c 3T3 cells at the end of 32 days. After transformation assay, the transformed cells were treated with various concentration of curcumin to evaluate cell viability, lactate dehydrogenase activity and DNA damage for 24h. The results revealed that curcumin decreased cell viability and increased the activity of lactate dehydrogenase enzyme in neoplastic transformed Balb/c 3T3 cells. In conclusion, the results demonstrated that curcumin has an anticancer effect on neoplastic transformed Balb/c 3T3 cells by causing DNA damage.


Subject(s)
Animals , Mice , Arsenic/toxicity , DNA Damage , Cell Transformation, Neoplastic , Curcumin/pharmacology , Fibroblasts/drug effects , BALB 3T3 Cells , Fibroblasts/pathology
13.
Braz. j. med. biol. res ; 54(10): e11203, 2021. tab, graf
Article in English | LILACS | ID: biblio-1285655

ABSTRACT

Phytochemical studies of the species Pavonia glazioviana were performed. Quercetin, kaempferol, acacetin, and trimethoxylated flavonoid compounds (which present biological activity) were isolated. We aimed to evaluate the in silico, in vitro, and ex vivo toxicity of flavonoid 5,7-dihydroxy-3,8,4'-trimethoxy (Pg-1) obtained from P. glazioviana through chemical structure analyses, toxicity assessment, and predictive bioactive properties, using human samples in in vitro tests. In silico analysis suggested that Pg-1 presents a good absorption index for penetrating biological membranes (for oral bioavailability), while also suggesting potential antimutagenic, anticarcinogenic, antioxidant, antineoplastic, anti-inflammatory, anti-hemorrhagic, and apoptosis agonist bioactivities. Assessment of hemolytic and genotoxic effects revealed low hemolysis rates in red blood cells with no cellular toxicity in oral mucosa cells. The reduced cytotoxic activity suggested the safety of the concentrations used (500-1000 µg/mL), and demonstrated the varied interactions of Pg-1 with the analyzed cells. The data obtained in the present study suggested potential therapeutic application, and the non-toxic profile indicated viability for future studies.


Subject(s)
Humans , Flavonoids/pharmacology , Plant Extracts , Computer Simulation , Apoptosis , Antioxidants/pharmacology
14.
Belo Horizonte; s.n; 2021. 115 p. ilus.
Thesis in Portuguese | LILACS, BBO | ID: biblio-1344175

ABSTRACT

No mercado encontramos uma grande variedade de materiais endodônticos disponibilizados para uso clínico, mas diversos estudos mostram divergências de opiniões com relação ao comportamento biológico dos diferentes materiais. Este trabalho teve como objetivos investigar a viabilidade celular, a expressão de genes envolvidos na plasticidade celular e a diferenciação celular em culturas de células- tronco recuperadas de polpa dentária humana (hDPSCs) quando em contato com quatro materiais endodônticos (Endofill, Pulp Canal Sealer, Sealer 26, MTA) rotineiramente utilizados na clínica odontológica. Objetivou também, por meio de uma revisão sistemática, analisar a biocompatibilidade de cimentos de uso endodôntico sobre células tronco de origem dental. Para isto, o metabolismo celular das hDPSCs, quando em contato com os capilares contendo ou não os cimentos, foi avaliado pelo ensaio de MTT (24 e 48 horas) e a viabilidade celular foi analisada pelo ensaio de exclusão do azul de tripan (48 horas). A plasticidade celular, na presença dos capilares contendo ou não os cimentos, foi avaliada pela expressão gênica dos marcadores CD34, CD45, Nestin, CD105, Nanog e OCT-4 por PCR. Finalmente, a diferenciação celular frente aos cimentos endodônticos foi verificada pela expressão dos genes RUNX2, ALP, OC/BGLAP e DMP1 por RT-PCR. Os dados foram analisados pelo teste ANOVA com correção de Bonferroni (p<0.05). Observou-se que os cimentos Pulp Canal Sealer e o Endofill reduziram significativamente a viabilidade e o metabolismo celular quando comparados ao controle após 48 horas (p<0.001). O MTA e o Sealer 26 não interferiram na viabilidade celular em ambos os períodos de avaliação (p>0.05). As hDPSCs, quando cultivadas na presença do MTA e Sealer 26, expressaram os marcadores Nestin, CD105, NANOG e OCT-4, e não expressaram CD34 e CD45. Por sua vez, o MTA e o Sealer 26 interferiram positivamente ou negativamente na expressão gênica de DMP1, OC/BGLAP e RUNX2 em relação ao grupo controle (p<0.05), mas não houve diferença significativa em relação à expressão gênica de ALP (p>0.05). Portanto, MTA e Sealer 26 demonstram boa compatibilidade biológica quando na presença das hDPSCs. A revisão sistemática demonstrou que a maioria dos materiais, apresentam boa compatibilidade quando em contato com as células tronco, estando aptos a serem utilizados na prática clínica.


On the market, we found a wide variety of endodontics cements available for clinical use, but several studies show divergences of opinion regarding the biological behavior of these different materials. This work aimed to investigate cell viability and metabolism, an expression of genes involved in cell plasticity and cell differentiation in stem cell cultures recovered from human dental pulp (hDPSCs) when in contact with four endodontic cements (Endofill, MTA, Pulp Canal Sealer, Sealer 26) routinely used in endodontic clinic. It also aimed, through a systematic review, to analyze the biocompatibility of endodontic materials on dental stem cells. For this, the viability and metabolism of hDPSCs, when it comes into contact with capillaries that included or not cements, was assessed by MTT assay (24 and 48 hours) and exclusion of trypan blue assay (48 hours). Cellular plasticity, with the presence of capillaries containing or not sealers, was evaluated by the genetic expression of the markers CD34, CD45, Nestin, CD105, Nanog and OCT-4 by PCR. Finally, cell differentiation from endodontics sealers was verified by the expression of the RUNX2, ALP, OC/BGLAP and DMP1 genes by RT-PCR. The data were analyzed using the ANOVA test with Bonferroni correction (p<0.05). We note that Pulp Canal Sealer and Endofill sealers decrease cell viability and cellular metabolism when compared to control after 48 hours (p<0.001). MTA and Sealer 26 did not interfere with cell viability in the two evaluation periods (p>0.05). hDPSCs, when grown in the presence of MTA and Sealer 26, express the Nestin, CD105, NANOG and OCT-4 markers, and do not express CD34 and CD45. In turn, MTA and Sealer 26 interfered in the gene expression of DMP1, OC/BGLAP and RUNX2 in relation to the control group (p<0.05), but did not find a significant difference in relation to the ALP gene expression (p>0.05). Therefore, MTA and Sealer 26 demonstrate good biological compatibility when in the presence of hDPSCs. The systematic review showed that almost all materials have good compatibility when in contact with stem cells, being able to be used in clinical practice.


Subject(s)
Cytotoxicity, Immunologic , Dental Cements , Dental Pulp , Endodontics , Genotoxicity , Mesenchymal Stem Cells
15.
Article in Chinese | WPRIM | ID: wpr-876148

ABSTRACT

@#pdr5 and snq2 gene knockout was constructed by overlap PCR, and the effects of pdr5 and snq2 mutations on the accuracy and sensitivity of RNR2 promoter-regulated yeast cell sensors in detecting genotoxic compounds were studied. The yeast cell sensors of wild-type, single-gene mutation of pdr5, single-gene mutation of snq2, and double-gene mutation of pdr5 and snq2 were studied. The cell growth inhibition and the fluorescence induction factor of the yeast cell sensors exposed to a series of concentrations of methyl methanesulfonate(MMS), ethyl methanesulfonate(EMS), cisplatin, 4-nitroquinoline-N-oxide(4NOQ), 5-fluorouracil(5-FU), hydroxyurea, salicylic acid and glucose solution were investigated. The results showed that overlap PCR method could efficiently construct the mutant yeast cell sensor. The accuracy of cell sensors of single-gene mutation of snq2 and double-gene mutation of pdr5 and snq2 were both 100%, higher than that of cell sensors of wild-type and single-gene mutation of pdr5 (87.5%). The yeast cell sensor of double-gene mutation of pdr5 and snq2 showed the highest sensitivity in detecting genotoxicity. This study provides guidance for the construction of high accuracy and sensitivity yeast cell sensor, and foundation for further functional research of yeast cell membrane transporter gene pdr5 and snq2.

16.
J Environ Biol ; 2020 Jul; 41(4): 672-679
Article | IMSEAR | ID: sea-214528

ABSTRACT

Aim: This study aimed to infer the ameliorative potential of Withania somnifera (‘Ashwagandha’) against hexavalent chromium induced micronuclei in Channa punctatus.Methodology: After laboratory acclimatization of 15 days, C. punctatus (12.20 cm, 42 g) were maintained in six groups. Group I, served as control. Fishes of groups II and III were separately exposed to root extract of W. somnifera (3 mg l-1) and 96 hr-LC50/10 of Cr (VI), 7.89 mg l-1, respectively, for 24, 48, 72 and 96 hr. Contrarily, the fish of groups IV, V and VI were exposed to 7.89 mg l-1 of Cr (VI) along with increasing concentrations of root extract of W. somnifera (1, 2, 3 mg l-1), respectively. Induction of micronuclei was assessed in fishes of all the six groups after stipulated exposure periods. Results: A significant induction (p<0.05) in micronuclei frequency was observed in Group-III as compared to the control. On contrary, there was a significant (p<0.05) decrease in frequency of micronuclei induction with increasing concentrations of root extract of W. somnifera, as compared to Group-III, after stipulated exposure periods in a dose and time-dependent manner. Interpretation: Preliminary investigations evinced that the root extract of W. somnifera has enough ameliorative potential against short term sub-lethal exposure to Cr (VI) induced genomic instability, i.e., micronuclei induction in C. punctatus.

17.
BAG, J. basic appl. genet. (Online) ; 31(1): 15-22, ilus, map, tab
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1124199

ABSTRACT

El test de micronúcleos (MN) es un biomarcador de genotoxicidad no destructivo que permite detectar daño cromosómico y otras alteraciones nucleares (AN). Phrynops hilarii es un quelonio de agua dulce que habita regiones del centro-norte de Argentina. El objetivo principal fue determinar la presencia de MN y otras AN en eritrocitos de poblaciones naturales de P. hilarii comparando sus frecuencias entre tres sitios, dos antropizados y uno de control (ciudades de Diamante y Paraná) de Entre Ríos, Argentina, durante el periodo 2015-2016. Dieciocho individuos (seis por sitio de muestreo) fueron evaluados en los sitios: 1- PD: Parque Nacional Pre-Delta (control), 2- AG: Salto Ander Egg (agroecosistema) y 3- SU: Caleta Club Náutico (sistema urbano). Se extrajo sangre de la vena femoral. Las muestras se tiñeron con el método May Grünwald-Giemsa y se observaron bajo un microscopio con el objetivo de inmersión. Las frecuencias de micronúcleos (FMN) y alteraciones nucleares (FAN) se determinaron cada 1000 eritrocitos observados. Se encontró diferencia significativa (p<0,05) entre el sitio PD y los otros sitios (AG y SU), tanto para FMN (p=0,0021) como para FAN (p=0,0011). Los valores de las frecuencias más altos correspondieron al sitio AG (FMN: 3,33±0,62; FAN: 4,67±0,56). Finalmente, el biomonitoreo con P. hilarii fue útil, por lo que podría considerarse como especie bioindicadora para evaluar la calidad de los ambientes de Argentina.


The micronucleus test (MN) is a biomarker of non-destructive genotoxicity that allows chromosomal damage and other nuclear alterations (NA) to be detected. Phrynops hilarii is a freshwater chelonium that inhabits regions of central-northern Argentina. The main objective was to determine the presence of MN and other NA in erythrocytes of natural populations of P. hilarii comparing their frequencies between three sites, two anthropized and one of control (cities of Diamante and Paraná) of Entre Ríos, Argentina, during the period 2015-2016. Eighteen individuals (six per sampling site) were evaluated at the sites: 1- PD: Pre-Delta National Park (control), 2- AG: Salto Ander Egg (agroecosystem) and 3- SU: Caleta Club Náutico (urban system). Blood was obtained from the femoral vein. The samples were stained with the May Grünwald-Giemsa method and observed under a microscope with an immersion objective. Micronucleus (MNF) and nuclear alterations (NAF) frequencies were determined every 1000 erythrocytes observed. A significant difference (p<0.05) was found between the PD site and the other sites (AG and SU), both for MNF (p=0.0021) and for NAF (p=0.0011). The highest frequency values corresponded to the AG site (MNF: 3.33 ± 0.62; NAF: 4.67 ± 0.56). Finally, biomonitoring with P. hilarii was useful, so it could be considered as a bioindicator species to assess the quality of Argentina's environments.

18.
J Environ Biol ; 2020 Mar; 41(2): 216-221
Article | IMSEAR | ID: sea-214496

ABSTRACT

Aim: To examine the possible role of nucleotide excision repair (NER) in affecting the ultimate mutagenic potency of 2,6- and 3,5-dimethylaniline (DMA) and their metabolites.Methodology: Two cell lines, nucleotide excision repair (NER)-proficient AA8 and deficient UV5 cells were treated with 50, 100, 250, 500 and 1000 μM of 2,6- and 3,5-DMA for 48 hr or their N-hydroxyl and aminophenol metabolites for 1 hr. Cell survival was determined by trypan blue exclusion assay, and 8-azaadenine-resistant mutants at adenine phosphoribosyltransferase (aprt) gene locus were evaluated.Results: A dose-dependent increase in cytotoxicity and mutant fraction was observed in AA8 and UV5 cells, treated with 2,6- and 3,5-DMA and their metabolites, but showed considerable variation in potency; N-hydroxyl and aminophenol metabolites of 2,6- and 3,5-DMA in serum-free α-minimal essential medium (MEM) having the highest potency, and 2,6- and 3,5-DMA in regular MEM at least. Repair-deficient UV5 cells were more sensitive to cytotoxic and mutagenic action than repair-proficient AA8 cells. Interpretation: These findings suggest that 2,6- and 3,5-DMA-induced DNA damage response may trigger cytotoxicity and mutagenicity when not completely repaired

19.
Article | IMSEAR | ID: sea-203740

ABSTRACT

The integral biological testing of soil samples of four districts of the Tula region was performed. The Tula regionwas selected for the study because it was subjected to radioactive contamination in 1986 but at present, it isconsidered to be fairly safe for that matter. The districts were selected according to both the presence of industrialpollution and relative ecological safety. The use/non-use of land for crop production was also taken into account(eight sites in total, samples № 1-8). Three different bioassays were used: microorganisms Salmonellatyphimurium, cell culture of mammalian Cricetulus griseus, and invertebrates Ceriodaphnia affinis. A relativelyhigh direct mutagenic activity was detected at the sites of the Efremovsky and Shchekino districts (№ 1 and № 3respectively), where the mutagenic index was 3.3 and 3.9 respectively. Substances contained in the № 2 and № 4soil extract samples turned out to be pro-mutagens, i.e. induced mutations upon using metabolic activation. Thesoil samples, such as № 1 and № 3 also showed genotoxicity in Cricetulus griseus cells with the increase of thefrequency of chromosomal and chromatid-type aberrations by several times, compared with control. In theexperiments on Ceriodaphnia affinis, toxicity was detected in the № 1, № 3, № 5 and № 7 samples, in which thedeath rate of the crustaceans was 35-45 %, whereas, in the remaining samples, the decrease in the survival rateof the crustaceans did not exceed 15 %. Therefore, the integral bio testing enables detection not only in thepresence of ecotoxicants but also it can indicate their origin - industrial or agricultural.

20.
J Environ Biol ; 2020 Jan; 41(1): 53-58
Article | IMSEAR | ID: sea-214472

ABSTRACT

Aim: The present study was performed to evaluate the genotoxic effect of 4-nonylphenol after acute and subchronic exposure in spleen tissue of Channa punctatus, recovery in DNA damage was also ascertained after 30 days of cessation of exposure.Methodology: Tail length (TL), tail intensity (TI), tail moment (TM), Olive tail moment (OTM) was used as biological indicators of DNA damage. The fish were exposed to different sublethal concentrations of 4-NP for 96 hrs (acute exposure) and for 90 days (sub chronic exposure). Results: Exposed groups showed significantly higher DNA damage in both acute and sub chronic exposure as compared to control groups. In the case of acute exposure, the highest damage was observed at 24 hr of exposure followed by a decline in the value of all the parameters, while in the later hours of exposure these value further increased. On the other hand, in the case of sub-chronic exposure, the highest damage was observed after treatment with 0.10 mg l-1 concentration of 4-NP at 90 days of exposure. Recovery experiment showed a decrease in the values of all the parameter’s studied, however, a significant decrease was observed only at the highest concentration. Interpretation: The results conclude the DNA damaging potential of 4-nonylphenol and highlighted the usage of spleen tissue for genotoxicity testing

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