Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 66
Filtrar
1.
Sci Rep ; 14(1): 13910, 2024 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886399

RESUMEN

N-nitrosodimethylamine (NDMA) and N-nitrosodiethylamine (NDEA), group 2A carcinogens, were detected in finished drug products, including metformin, ranitidine, sartans and other drugs which caused multiple recalls in the USA and Europe. Important studies also reported the formation of NDMA when ranitidine and nitrite were added to simulated gastric fluid. Our objective was to screen finished drug products from Europe and USA for nitrosamine impurities and investigate the formation of NDMA in metformin finished drug products when added to simulated gastric fluid. One dosage unit of 30 different commercially available drugs, including metformin, sartans, and ranitidine were tested for NDMA, NDEA, and dimethylformamide (DMF) impurities, using a liquid chromatography-mass spectrometry (LC-MS) method. Then, 6 metformin finished drug products were tested in stomach conditions for 2 h at 37 °C in a 100 mL solution with a pH of 2.5 and different nitrite concentrations (40, 10, 1, 0.1 mM) and tested for NDMA, and DMF using LC-MS. We measured NDMA, NDEA, and DMF in 30 finished drug products. NDMA and DMF were quantified for metformin drug products in simulated gastric fluid with different nitrite concentrations. None of the 30 drugs showed concerning levels of NDMA, NDEA, or DMF when tested as single tablets. However, when metformin tablets are added to simulated gastric fluid solutions with high nitrite concentrations (40 mM and 10 mM), NDMA can reach amounts of thousands of nanograms per tablet. At the closest concentration to physiologic conditions we used, 1 mM, NDMA is still present in the hundreds of nanograms in some metformin products. In this in vitro study, nitrite concentration had a very important effect on NDMA quantification in metformin tablets added to simulated gastric fluid. 1 mM nitrite caused an increase above the acceptable daily intake set by the U.S. Food and Drug Administration (FDA) for some of the metformin drugs. 10 mM, 40 mM nitrite solutions generated NDMA amounts exceeding by more than a hundred times the acceptable daily intake set by the FDA of 96 nanograms. These findings suggest that metformin can react with nitrite in gastric-like conditions and generate NDMA. Thus, patients taking metformin could be exposed to NDMA when high nitrite levels are present in their stomach, and we recommend including a statement within the Patient Package Inserts/Instructions for use.


Asunto(s)
Dimetilnitrosamina , Metformina , Nitritos , Metformina/análisis , Metformina/química , Dimetilnitrosamina/análisis , Dimetilnitrosamina/química , Nitritos/análisis , Contaminación de Medicamentos , Humanos , Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Jugo Gástrico/química
2.
J Am Soc Mass Spectrom ; 35(8): 1657-1668, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-38716699

RESUMEN

N-nitrosamines (NAs) are prevalent mutagenic impurities in various consumer products. Their discovery in valsartan-containing medicines in 2018 prompted global regulatory agencies to set guidelines on their presence and permissible levels in pharmaceuticals. In order to determine the NAs content in medicines, efficient and sensitive analytical methods have been developed based on mass spectrometry techniques. Direct analysis in real time-mass spectrometry (DART-MS) has emerged as a prominent ambient ionization technique for pharmaceutical analysis due to its high-throughput capability, simplicity, and minimal sample preparation requirements. Thus, in this study DART-MS was evaluated for the screening and quantification of NAs in medicines. DART-MS analyses were conducted in positive ion mode, for both direct tablet analysis and solution analysis. The analytical performance was evaluated regarding linearity, precision, accuracy, limits of detection, and quantification. The DART-MS proved to be suitable for the determination of NAs in medicines, whether through direct tablet analysis or solution analysis. The analytical performance demonstrated linearity in the range from 1.00 to 200.00 ng mL-1, limits of quantification about 1.00 ng mL-1, precision and accuracy lower than 15%, and no significant matrix effect for six drug-related NAs. In conclusion, the DART-MS technique demonstrated to be an alternative method to determine NAs in medicines, aligning with the principles of green chemistry.


Asunto(s)
Contaminación de Medicamentos , Límite de Detección , Espectrometría de Masas , Nitrosaminas , Nitrosaminas/análisis , Espectrometría de Masas/métodos , Comprimidos/análisis , Reproducibilidad de los Resultados
3.
Arch Biochem Biophys ; 757: 110043, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38789086

RESUMEN

The oncogene and drug metabolism enzyme glutathione S-transferase P (GSTP) is also a GSH-dependent chaperone of signal transduction and transcriptional proteins with key role in liver carcinogenesis. In this study, we explored this role of GSTP in hepatocellular carcinoma (HCC) investigating the possible interaction of this protein with one of its transcription factor and metronome of the cancer cell redox, namely the nuclear factor erythroid 2-related factor 2 (Nrf2). Expression, cellular distribution, and function as glutathionylation factor of GSTP1-1 isoform were investigated in the mouse model of N-nitrosodiethylamine (DEN)-induced HCC and in vitro in human HCC cell lines. The physical and functional interaction of GSTP protein with Nrf2 and Keap1 were investigated by immunoprecipitation and gene manipulation experiments. GSTP protein increased its liver expression, enzymatic activity and nuclear levels during DEN-induced tumor development in mice; protein glutathionylation (PSSG) was increased in the tumor masses. Higher levels and a preferential nuclear localization of GSTP protein were also observed in HepG2 and Huh-7 hepatocarcinoma cells compared to HepaRG non-cancerous cells, along with increased basal and Ebselen-stimulated levels of free GSH and PSSG. GSTP activity inhibition with the GSH analogue EZT induced apoptotic cell death in HCC cells. Hepatic Nrf2 and c-Jun, two transcription factors involved in GSTP expression and GSH biosynthesis, were induced in DEN-HCC compared to control animals; the Nrf2 inhibitory proteins Keap1 and ß-TrCP also increased and oligomeric forms of GSTP co-immunoprecipitated with both Nrf2 and Keap1. Nrf2 nuclear translocation and ß-TrCP expression also increased in HCC cells, and GSTP transfection in HepaRG cells induced Nrf2 activation. In conclusion, GSTP expression and subcellular distribution are modified in HCC cells and apparently contribute to the GSH-dependent reprogramming of the cellular redox in this type of cancer directly influencing the transcriptional system Nrf2/Keap1.


Asunto(s)
Carcinoma Hepatocelular , Gutatión-S-Transferasa pi , Proteína 1 Asociada A ECH Tipo Kelch , Neoplasias Hepáticas , Factor 2 Relacionado con NF-E2 , Factor 2 Relacionado con NF-E2/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Animales , Humanos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Ratones , Gutatión-S-Transferasa pi/metabolismo , Gutatión-S-Transferasa pi/genética , Masculino , Línea Celular Tumoral , Células Hep G2 , Glutatión/metabolismo
4.
Food Chem Toxicol ; 186: 114519, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38369053

RESUMEN

N-Nitrosodiethylamine (NDEA), a carcinogen in some foods and medications, is linked to liver damage similar to non-alcoholic fatty liver disease (NAFLD). This study explores how NDEA disrupts liver lipid metabolism. Sprague-Dawley rats were given two doses of NDEA (100 mg/kg) orally, 24 h apart. Liver response was assessed through tissue staining, blood tests, and biochemical markers, including fatty acids, lipid peroxidation, and serum very-low density lipoprotein (VLDL) levels. Additionally, lipidomic analysis of liver tissues and serum was performed. The results indicated significant hepatic steatosis (fat accumulation in the liver) following NDEA exposure. Blood analysis showed signs of inflammation and liver damage. Biochemical tests revealed decreased liver protein synthesis and specific enzyme alterations, suggesting liver cell injury but maintaining mitochondrial function. Increased fatty acid levels without a rise in lipid peroxidation were observed, indicating fat accumulation. Lipidomic analysis showed increased polyunsaturated triglycerides in the liver and decreased serum VLDL, implicating impaired VLDL transport in liver dysfunction. In conclusion, NDEA exposure disrupts liver lipid metabolism, primarily through the accumulation of polyunsaturated triglycerides and impaired fat transport. These findings provide insight into the mechanisms of NDEA-induced liver injury and its progression to hepatic steatosis.


Asunto(s)
Dietilnitrosamina , Enfermedad del Hígado Graso no Alcohólico , Ratas , Animales , Triglicéridos/metabolismo , Dietilnitrosamina/toxicidad , Lipoproteínas VLDL/metabolismo , Ratas Sprague-Dawley , Hígado/metabolismo , Enfermedad del Hígado Graso no Alcohólico/inducido químicamente , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Metabolismo de los Lípidos , Lipoproteínas LDL/metabolismo , Dieta Alta en Grasa
5.
J Appl Toxicol ; 44(8): 1108-1128, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38212177

RESUMEN

The International Agency for Research on Cancer has classified N-nitrosodiethylamine (NDEA) as a possible carcinogen and mutagenic substances, placing it in category 2A of compounds that are probably harmful to humans. It is found in nature and tobacco smoke, along with its precursors, and is also synthesized endogenously in the human body. The oral or parenteral administration of a minimal quantity of NDEA results in severe liver and kidney organ damage. The NDEA required bioactivation by CYP450 enzyme to form DNA adduct in the alkylation mechanism. Thus, this bioactivation directs oxidative stress and injury to cells due to the higher formation of reactive oxygen species and alters antioxidant system in tissues, whereas free radical scavengers guard the membranes from NDEA-directed injury in many enzymes. This might be one of the reasons in the etiology of cancer that is not limited to a certain target organ but can affect various organs and organ systems. Although there are various possible approaches for the treatment of NDEA-induced cancer, their therapeutic outcomes are still very dismal. However, several precautions were considered to be taken during handling or working with NDEA, as it considered being the best way to lower down the occurrence of NDEA-directed cancers. The present review was designed to enlighten the general guidelines for working with NDEA, possible mechanism, to alter the antioxidant line to cause malignancy in different parts of animal body along with its protective agents. Thus, revelation to constant, unpredictable stress situations even in common life may remarkably augment the toxic potential through the rise in the oxidative stress and damage of DNA.


Asunto(s)
Carcinógenos , Dietilnitrosamina , Dietilnitrosamina/toxicidad , Humanos , Carcinógenos/toxicidad , Medición de Riesgo , Animales , Estrés Oxidativo/efectos de los fármacos , Neoplasias/inducido químicamente
6.
Ecotoxicol Environ Saf ; 270: 115841, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38113799

RESUMEN

N-nitrosodiethylamine (ND) is an extremely toxic unavoidable environmental contaminant. CopperII-albumin (CuAB) complex, a newly developed Cu complex, showed antioxidant and anti-inflammatory potential. Hereby, we explored the plausible neuroprotective role of CuAB complex toward ND-evoked neurotoxicity in mice. Twenty-four male mice were sorted into 4 groups (6 mice each). Control group, mice were administered oral distilled water; and CuAB group, mice received CuAB complex at a dose of 817 µg/kg orally, three times weekly. In ND group, ND was given intraperitoneally (50 mg/kg body weight, once weekly for 6 w). CuAB+ND group, mice were administered a combination of CuAB and ND. The brain was quickly extracted upon completion of the experimental protocol for the evaluation of the oxidative/antioxidative markers, inflammatory cytokines, and histopathological examination. Oxidative stress was induced after ND exposure indicated by a reduction in GSH and SOD1 level, with increased MDA level. In addition, decreased expression of SOD1 proteins, Nrf2, and 5-HT mRNA expression levels were noticed. An apoptotic cascade has also been elicited, evidenced by overexpression of Cyt c, Cl. Casp 3. In addition, increased regulation of proinflammatory genes (TNF-α, IL-6, iNOS, Casp1, and NF-κB (p65/p50); besides, increment of protein expression of P-IKBα and reduced expression of IKBα. Pretreatment with CuAB complex significantly ameliorated ND neuronal damage. Our results recommend CuAB complex supplementation because it exerts neuroprotective effects against ND-induced toxicity.


Asunto(s)
Cobre , Síndromes de Neurotoxicidad , Ratones , Masculino , Animales , Cobre/toxicidad , Dietilnitrosamina/farmacología , Superóxido Dismutasa-1/metabolismo , FN-kappa B/genética , FN-kappa B/metabolismo , Estrés Oxidativo , Transducción de Señal , Antioxidantes/farmacología , Antioxidantes/metabolismo , Síndromes de Neurotoxicidad/tratamiento farmacológico , Síndromes de Neurotoxicidad/etiología , Síndromes de Neurotoxicidad/prevención & control , Factor 2 Relacionado con NF-E2/metabolismo
7.
Food Chem Toxicol ; 182: 114096, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37858842

RESUMEN

Hepatocellular carcinoma (HCC) is the most frequent primary malignancy of the liver. The aim of this study is to evaluate the comparative in silico and in vivo ameliorative potential of the ethanolic extract of Curcuma longa (EECL) in male and female Wistar rats administered N-nitrosodiethylamine-induced hepatocellular carcinoma. The MAPK compound was obtained from a protein data bank (PDB ID: 7AUV) for molecular docking. One hundred and twenty Wistar rats, were randomly selected into twelve groups (n = 5): Group A received regular diets as a basal control; groups B to G were administered 100 mg/kg NDEA twice in two weeks; while groups C to E received 200 mg/kg, 400 mg/kg, and 600 mg/kg of EECL; group F was treated with 200 mg/kg pure curcumin; and group G received 100 mg/kg Sylibon-140. Group H received only 200 mg/kg pure curcumin, and group I received 200 mg/kg of dimethylsulfoxide (DMSO). Groups J, K, and L received 200 mg/kg, 400 mg/kg and 600 mg/kg of EECL. MAPK and AFP mRNA in Wistar rats administered NDEA were upregulated as compared to EECL groups. In conclusion, the in silico and in vitro study validates the mitigating role of ethanolic extract of Curcuma longa and pure curcumin.


Asunto(s)
Carcinoma Hepatocelular , Curcumina , Neoplasias Hepáticas , Ratas , Masculino , Femenino , Animales , Ratas Wistar , Curcumina/farmacología , Curcuma , Carcinoma Hepatocelular/tratamiento farmacológico , Proteínas Quinasas Activadas por Mitógenos , Simulación del Acoplamiento Molecular , Neoplasias Hepáticas/tratamiento farmacológico , Extractos Vegetales/farmacología , Etanol
8.
Artículo en Inglés | MEDLINE | ID: mdl-37770142

RESUMEN

N-Nitrosodiethylamine (NDEA), a well-studied N-nitrosamine, was tested in rats to compare the dose-response relationship of three genotoxicity endpoints. Mutant / mutation frequencies were determined using the transgenic rodent (TGR) gene mutation assay and error corrected next generation sequencing (ecNGS) (i.e., duplex sequencing (DS)), and genetic damage was detected by the alkaline comet assay. Big Blue® (cII Locus) animals (n = 6 per dose group) were administered doses of 0.001, 0.01, 0.1, 1, 3 mg/kg/day NDEA by oral gavage. Samples were collected for cII mutation and DS analyses following 28-days of exposure and 3 days recovery. In a separate study, male Sprague-Dawley (SD) rats (n = 6 per dose group) were administered the same doses by oral gavage for two consecutive days and then samples collected for the alkaline comet assay. A dose-related increase in mutant / mutation frequencies of the liver but not duodenum was observed using the TGR assay and DS with DS resulting in a slightly more sensitive response, with a lower benchmark dose (BMD). In addition, a dose-related increase in percent tail DNA was observed in the liver using the alkaline comet assay. Therefore, DS and comet assays showed good utility for hazard identification and dose-response analysis of a representative N-nitrosamine comparable to the TGR gene mutation assay.


Asunto(s)
Dietilnitrosamina , Nitrosaminas , Ratas , Animales , Masculino , Ensayo Cometa/métodos , Dietilnitrosamina/toxicidad , Roedores , Ratas Sprague-Dawley , Mutación , Animales Modificados Genéticamente , Daño del ADN , Secuenciación de Nucleótidos de Alto Rendimiento , Pruebas de Mutagenicidad/métodos , Relación Dosis-Respuesta a Droga
9.
Biomolecules ; 13(9)2023 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-37759689

RESUMEN

N-nitrosodiethylamine (NDEA) is a potential carcinogen known to cause liver tumors and chronic inflammation, diabetes, cognitive problems, and signs like Alzheimer's disease (AD) in animals. This compound is classified as probably carcinogenic to humans. Usual sources of exposure include food, beer, tobacco, personal care products, water, and medications. AD is characterized by cognitive decline, amyloid-ß (Aß) deposit, tau hyperphosphorylation, and cell loss. This is accompanied by neuroinflammation, which involves release of microglial cytokines, such as tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin 1ß (IL-1ß), by nuclear factor kappa B (NF-κB) upregulation; each are linked to AD progression. Weak PI3K/Akt insulin-signaling inhibits IRS-1 phosphorylation, activates GSK3ß and promotes tau hyperphosphorylation. Metformin, an antihyperglycemic agent, has potent anti-inflammatory efficacy. It reduces proinflammatory cytokines such as IL-6, IL-1ß, and TNF-α via NF-κB inhibition. Metformin also reduces reactive oxidative species (ROS) and modulates cognitive disorders reported due to brain insulin resistance links. Our study examined how NDEA affects spatial memory in Wistar rats. We found that all NDEA doses tested impaired memory. The 80 µg/kg dose of NDEA increased levels of Aß1-42, TNF-α, and IL-6 in the hippocampus, which correlated with memory loss. Nonetheless, treatment with 100 mg/kg of metformin attenuated the levels of pro-inflammatory cytokines and Aß1-42, and enhanced memory. It suggests that metformin may protect against NDEA-triggered memory issues and brain inflammation.


Asunto(s)
Enfermedad de Alzheimer , Metformina , Animales , Ratas , Enfermedad de Alzheimer/inducido químicamente , Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides , Carcinógenos , Citocinas , Dietilnitrosamina , Hipocampo , Interleucina-6 , Trastornos de la Memoria/inducido químicamente , Trastornos de la Memoria/tratamiento farmacológico , Metformina/farmacología , Metformina/uso terapéutico , FN-kappa B , Fosfatidilinositol 3-Quinasas , Ratas Wistar , Factor de Necrosis Tumoral alfa
10.
Cell Biochem Funct ; 41(8): 1188-1199, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37732723

RESUMEN

Organisms frequently suffer negative effects from large doses of ionizing radiation. However, radiation is not as hazardous at lower doses as was once believed. The current study aims to evaluate the possible radio-adaptive effect induced by low-dose radiation (LDR) in modulating high-dose radiation (HDR) and N-nitrosodiethylamine (NDEA)-induced lung injury in male albino rats. Sixty-four male rats were randomly divided into four groups: Group 1 (control): normal rats; Group 2 (D): rats given NDEA in drinking water; Group 3 (DR): rats administered with NDEA then exposed to fractionated HDR; and Group 4 (DRL): rats administered with NDEA then exposed to LDR + HDR. In the next stage, malondialdehyde (MDA), glutathione reduced (GSH), catalase (CAT), and superoxide dismutase (SOD) levels in the lung tissues were measured. Furthermore, the enzyme-linked immunoassay analysis technique was performed to assess the Toll-like receptor 4 (TLR4), interleukin-1 receptor-associated kinase 4 (IRAK4), and mitogen-activated protein kinases (MAPK) expression levels. Histopathological and DNA fragmentation analyses in lung tissue, in addition to hematological and apoptosis analyses of the blood samples, were also conducted. Results demonstrated a significant increase in antioxidant defense and a reduction in MDA levels were observed in LDR-treated animals compared to the D and DR groups. Additionally, exposure to LDR decreased TLR4, IRAK4, and MAPK levels, decreased apoptosis, and restored all the alterations in the histopathological, hematological parameters, and DNA fragmentation, indicating its protective effects on the lung when compared with untreated rats. Taken together, LDR shows protective action against the negative effects of subsequent HDR and NDEA. This impact may be attributable to the adaptive response induced by LDR, which decreases DNA damage in lung tissue and activates the antioxidative, antiapoptotic, and anti-inflammatory systems in the affected animals, enabling them to withstand the following HDR exposure.


Asunto(s)
Quinasas Asociadas a Receptores de Interleucina-1 , Hígado , Ratas , Masculino , Animales , Hígado/metabolismo , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , Quinasas Asociadas a Receptores de Interleucina-1/farmacología , Receptor Toll-Like 4/metabolismo , Antioxidantes/farmacología , Glutatión/metabolismo , Dietilnitrosamina/metabolismo , Dietilnitrosamina/farmacología , Transducción de Señal , Pulmón/metabolismo , Estrés Oxidativo
11.
Foods ; 12(7)2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-37048366

RESUMEN

This study was conducted with the aim of determining the effects of different black garlic (BG) levels (1%, 2% and 3%) on quality characteristics of a semi-dry fermented sausage (heat-treated sucuk). In addition, the effect of cooking time (0, 1 or 3 min at 180 °C on a hot plate) on nitrosamine formation was investigated. Fresh garlic (FG, 1%) was evaluated as the control group. BG (2% and 3%) caused a reduction in the count of lactic acid bacteria while leading to an increase in pH. FG1% gave the highest number of Micrococcus/Staphylococcus, as well as aw value. The thiobarbituric acid reactive substance (TBARS) value increased with increasing BG levels. FG (1%) showed the highest residual nitrite amount (p < 0.05). The scores for color, taste and general acceptability were reduced by the use of BG (p < 0.05). No significant difference was observed between the garlic treatments in terms of N-Nitrosodimethylamine (NDMA) and N-Nitrosodiethylamine (NDEA) when no additional cooking was applied. Cooking time was determined to have no significant effect on NDMA in 3% BG. The use of BG caused an increase in N-Nitrosopiperidine (NPIP) (p < 0.05). As for PCA, a closer correlation between NPIP and the groups containing BG was observed, while there was a strong correlation between NDMA and the FG group cooked for 3 min. The use of BG caused an increase in NPIP, but affected NDMA and NDEA depending on the cooking time.

12.
Food Chem ; 416: 135759, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-36893642

RESUMEN

The potent two-phase hollow fiber electromembrane extraction technique coupled to gas chromatography mass spectrometry (HF-EME/GC-MS) was proposed for the determination of six types of carcinogen nitrosamines in sausages samples. Two steps of sample digestion were accomplished for the complete removal of fat globules and efficient release of target analytes. The extraction principle was based on electro-migration of target analytes via specific fiber to extraction solvent. 2-Nitrophenyl octyl ether (NPOE) was dexterously employed as both supported liquid membrane and extraction solvent, which is compatible with GC-MS. After the extraction process, the NPOE containing nitrosamines was directly injected to GC-MS without extra steps requirement to reduce analysis time. The consequences revealed that N-nitrosodiethylamine (NDEA) as the most potent carcinogen has the highest concentration in fried and oven-cooked sausages with 70% of red meat. The meat type and amount and also cooking process could significantly effect on nitrosamines formation.


Asunto(s)
Nitrosaminas , Nitrosaminas/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Carne/análisis , Carcinógenos/análisis , Solventes , Culinaria
13.
J Hazard Mater ; 450: 131094, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-36867906

RESUMEN

N-nitrosamines are formed during different industrial processes and are of significant concern due to their carcinogenic and mutagenic properties. This study reports concentrations of N-nitrosamines in eight different industrial wastewater treatment plants in Switzerland and the variability of their abundance. Only four N-nitrosamines species, N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA), N-nitrosodibutylamine (NDPA) and N-nitrosomorpholine (NMOR) were above the limit of quantification in this campaign. Remarkably high concentrations (i.e. up to 975 µg NDMA/L, 90.7 µg NDEA/L, 1.6 µg NDPA/L and 710 µg NMOR/L) of these N-nitrosamines were detected at seven of eight sites. These concentrations are two to five orders of magnitude higher than those typically detected in municipal wastewater effluents. These results suggest that industrial effluents may be a major source of N-nitrosamines. Although very high concentrations of N-nitrosamine have been detected in industrial discharges, various processes in surface water can partially mitigate their concentrations (e.g. photolysis, biodegradation and volatilization) and hence the risk to human health and aquatic ecosystems. Nevertheless, there is little information on long-term effects on aquatic organisms and therefore the discharge of N-nitrosamines to the environment should be avoided until the impact on ecosystems is assessed. During winter a less efficient mitigation of N-nitrosamines can be expected (lower biological activity, less sunlight) and therefore, emphasis should be put on this season in future risk assessment studies.


Asunto(s)
Ecosistema , Nitrosaminas , Humanos , Suiza , Dimetilnitrosamina , Dietilnitrosamina
14.
Saudi Pharm J ; 31(2): 295-311, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36942272

RESUMEN

Over the last two years, global regulatory authorities have raised safety concerns on nitrosamine contamination in several drug classes, including angiotensin II receptor antagonists, histamine-2 receptor antagonists, antimicrobial agents, and antidiabetic drugs. To avoid carcinogenic and mutagenic effects in patients relying on these medications, authorities have established specific guidelines in risk assessment scenarios and proposed control limits for nitrosamine impurities in pharmaceuticals. In this review, nitrosation pathways and possible root causes of nitrosamine formation in pharmaceuticals are discussed. The control limits of nitrosamine impurities in pharmaceuticals proposed by national regulatory authorities are presented. Additionally, a practical and science-based strategy for implementing the well-established control limits is notably reviewed in terms of an alternative approach for drug product N-nitrosamines without published AI information from animal carcinogenicity testing. Finally, a novel risk evaluation strategy for predicting and investigating the possible nitrosation of amine precursors and amine pharmaceuticals as powerful prevention of nitrosamine contamination is addressed.

15.
Arch Biochem Biophys ; 728: 109375, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-35970414

RESUMEN

Chitosan is a natural polyfunctional polymer that can be modified to achieve compounds with tailored properties for targeting and treating different cancers. In this study, we report the development and anticancer potential of phosphorylated galactosylated chitosan (PGC). The synthesized compound was characterized by FT-IR, NMR, and mass spectroscopy. The interaction of PGC with asialoglycoprotein receptors (ASGPR) and cellular internalization in HepG2 cells was studied using in silico and uptake studies respectively. PGC was evaluated for its metal chelating, ferric ion reducing, superoxide, and lipid peroxide (LPO) inhibiting potential. Further, anticancer therapeutic potential of PGC was evaluated against N-nitrosodiethylamine (NDEA)-induced hepatocellular carcinoma in a mice model. After development of cancer, PGC was administered to the treatment group (0.5 mg/kg bw, intravenously), once a week for 4 weeks. Characterization studies of PGC revealed successful phosphorylation and galactosylation of chitosan. A strong interaction of PGC with ASGP-receptors was predicted by computational studies and cellular internalization studies demonstrated 98.76 ± 0.53% uptake of PGC in the HepG2 cells. A good metal chelating, ferric ion reducing, and free radical scavenging activity was demonstrated by PGC. The anticancer therapeutic potential of PGC was evident from the observation that PGC treatment increased number of tumor free animals (50%) (6/12) and significantly (p ≤ 0.05) lowered tumor multiplicity as compared to untreated tumor group.


Asunto(s)
Carcinoma Hepatocelular , Quitosano , Neoplasias Hepáticas , Aminas , Animales , Ratones , Espectroscopía Infrarroja por Transformada de Fourier
16.
Acta Pharm Sin B ; 12(5): 2252-2267, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35646530

RESUMEN

Aristolochic acids (AAs) have long been considered as a potent carcinogen due to its nephrotoxicity. Aristolochic acid I (AAI) reacts with DNA to form covalent aristolactam (AL)-DNA adducts, leading to subsequent A to T transversion mutation, commonly referred as AA mutational signature. Previous research inferred that AAs were widely implicated in liver cancer throughout Asia. In this study, we explored whether AAs exposure was the main cause of liver cancer in the context of HBV infection in mainland China. Totally 1256 liver cancer samples were randomly retrieved from 3 medical centers and a refined bioanalytical method was used to detect AAI-DNA adducts. 5.10% of these samples could be identified as AAI positive exposure. Whole genome sequencing suggested 8.41% of 107 liver cancer patients exhibited the dominant AA mutational signature, indicating a relatively low overall AAI exposure rate. In animal models, long-term administration of AAI barely increased liver tumorigenesis in adult mice, opposite from its tumor-inducing role when subjected to infant mice. Furthermore, AAI induced dose-dependent accumulation of AA-DNA adduct in target organs in adult mice, with the most detected in kidney instead of liver. Taken together, our data indicate that AA exposure was not the major threat of liver cancer in adulthood.

17.
F1000Res ; 11: 289, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36726605

RESUMEN

Background:  Sorafenib is an expensive standard drug used for advanced hepatocellular carcinoma. Its combination with epigallo-3-catechin gallate leads to a reduced cost but equally effective anti-angiogenic effect. Therefore, this study aims to assess the anti-angiogenic effect of standard-dose Sorafenib compared to the combination of low-dose Sorafenib and epigallo-3-catechin gallate. Methods:  A total of 25 male Wistar rats (7-weeks-old) were randomly divided into 4 groups, namely Sham (K), Control (O), combination of low-dose Sorafenib and epigallo-3-catechin gallate group (X1), and standard-dose Sorafenib group (X2). All groups were injected with N-Nitrosodiethylamine 70 mg/kg bodyweight (BW) intraperitoneally for 10 weeks, except the Sham group. After the development of hepatocellular carcinoma, X1 and X2 were treated for 2 weeks. Subsequently, the level of vascular endothelial growth factor (VEGF) and expression of microvascular density was examined using liver tissues. Results: There was a significant difference (p=0.007) in the level of VEGF between the group X1 (106,682 ± 41,024) and X2 (214,5162 ± 67,71652). However, the differences in VEGF level of group X1 and X2 compared to group O (318,101 ± 55,078) were significantly lower, with values p=0.000136 and p=0.019, respectively. The expression of microvascular density between groups X1 (36 ± 4,416) and X2 (26,2 ± 4,55) was not significantly different. Meanwhile, a significant difference (p<0.05) was discovered when both groups were compared with group O (176 ± 19). Conclusion: The combination of low-dose Sorafenib with epigallo-3-catechin gallate is superior in reducing the level of VEGF compared to standard-dose Sorafenib and is better than the control. Standard-dose Sorafenib as well as the combination of low-dose Sorafenib and epigallo-3-catechin gallate have similar effectivity to reduce the expression of microvascular density.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Sorafenib , Animales , Masculino , Ratas , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Ratas Wistar , Sorafenib/farmacología , Factor A de Crecimiento Endotelial Vascular
19.
J Biochem Mol Toxicol ; 36(3): e22968, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34820934

RESUMEN

The development of bioengineered nanoparticles has attracted considerable universal attention in the field of medical science and disease treatment. Current studies were executed to evaluate the hepatoprotective activity of biosynthesized silver nanoparticles (AgNPs). Their characterization was performed by UV-Visible analysis, fourier transform infrared spectroscopy, transmission electron microscopy (TEM), scanning electron microscope (SEM), and Zeta analyses. In in vivo studies, albino rats (180 ± 10 g) were persuaded with model hepatic toxicant N-nitrosodiethylamine (NDEA) and subsequently cotreated with Morus multicaulis at 100 mg/kg and AgNPs at 100 µg/kg dose. NDEA administration elevates the levels of liver function test biomarkers, which were reinstated to normal by cotreatment of test drugs. The oxidative stress and concentration of drug-metabolizing enzyme increase after induction of toxicant (NDEA), these markers are restored toward normal after cotreatment of nano-drug. Treatments of M. multicaulis extract did not show such significant protection. The NDEA-treated groups showed a significant rise in the level of cytokines (interleukin [IL-6] and IL-10) and reached normal with subsequent treatment with AgNPs. Histopathological studies also exhibited the curative effect of AgNPs in the same manner. Thus current results strongly suggest that biomimetic AgNPs could be used as an effective drug against hepatic alteration.


Asunto(s)
Materiales Biomiméticos , Enfermedad Hepática Inducida por Sustancias y Drogas , Dietilnitrosamina/toxicidad , Nanopartículas del Metal , Plata , Animales , Materiales Biomiméticos/síntesis química , Materiales Biomiméticos/química , Materiales Biomiméticos/farmacología , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Masculino , Nanopartículas del Metal/química , Nanopartículas del Metal/uso terapéutico , Ratas , Ratas Wistar , Plata/química , Plata/farmacología
20.
J Basic Clin Physiol Pharmacol ; 32(4): 505-510, 2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-34214328

RESUMEN

OBJECTIVES: For designing early treatment for liver cancer, it is important to prepare an animal model to evaluate cancer prevention treatment by using inflammation disease. The hepatocarcinogenic N-Nitrosodiethylamine (NDEA) has been reportedly able to produce free radicals that cause liver inflammation leading to liver carcinoma. This study aimed to evaluate the inflammation disease model of mice induced with hepatocarcinogenic NDEA for five weeks induction. METHODS: The BALB-c mice were induced with NDEA 25 mg/kg of body weight once a week for five weeks intraperitonially and it was then evaluated for the body weight during study periods. The mice were then sacrificed and excised for evaluating their organs including physical and morphological appearances and histopathology evaluations. RESULTS: The results showed a significant decrease of body weight of mice after five times induction of 25 mg NDEA/kgBW per week intraperitonially. Different morphological appearances and weight of mice organs specifically for liver and spleen had also been observed. The histopathology examination showed that there were hepatic lipidosis and steatohepatitis observed in liver and spleen, respectively that might indicate the hepatocellular injury. CONCLUSIONS: It can be concluded that inducing mice with NDEA intraperitonially resulted in fatty liver disease leading to progress of cancer disease.


Asunto(s)
Dietilnitrosamina , Neoplasias Hepáticas Experimentales , Animales , Peso Corporal , Dietilnitrosamina/toxicidad , Inflamación/inducido químicamente , Hígado , Neoplasias Hepáticas Experimentales/inducido químicamente , Ratones , Ratones Endogámicos BALB C
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA