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1.
Int J Mol Sci ; 24(15)2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37569836

RESUMO

The Food and Drug Administration has recently classified the IQOS electronic cigarette as a modified-risk tobacco product. However, IQOS cigarettes still release various harmful constituents typical of conventional cigarettes (CCs), although the concentrations are markedly lower. Here, we investigated the damaging effects of IQOS smoking on the liver. Male Sprague Dawley rats were exposed, whole body, 5 days/week for 4 weeks to IQOS smoke (4 sticks/day), and hepatic xenobiotic metabolism, redox homeostasis and lipidomic profile were investigated. IQOS boosted reactive radicals and generated oxidative stress. Exposure decreased cellular reserves of total glutathione (GSH) but not GSH-dependent antioxidant enzymes. Catalase and xanthine oxidase were greater in the exposed group, as were various hepatic CYP-dependent monooxygenases (CYP2B1/2, CYP1A1, CYP2A1, CYP2E1-linked). Respiratory chain activity was unaltered, while the number of liver mitochondria was increased. IQOS exposure had an impact on the hepatic lipid profile. With regard to the expression of some MAP kinases commonly activated by CC smoking, IQOS increased the p-p38/p38 ratio, while erythroid nuclear transcription factor 2 (Nrf2) was negatively affected. Our data suggest that IQOS significantly impairs liver function, supporting the precautionary stance taken by the WHO toward the use of these devices, especially by young people and pregnant women.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Gravidez , Ratos , Animais , Masculino , Feminino , Humanos , Fumaça , Ratos Sprague-Dawley , Produtos do Tabaco/efeitos adversos , Fígado
2.
Nicotine Tob Res ; 23(12): 2127-2134, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34036368

RESUMO

INTRODUCTION: Recently, the Food and Drug Administration authorized the marketing of IQOS Tobacco Heating System as a Modified Risk Tobacco Product based on an electronic heat-not-burn technology that purports to reduce the risk. METHODS: Sprague-Dawley rats were exposed in a whole-body mode to IQOS aerosol for 4 weeks. We performed the chemical characterization of IQOS mainstream and we studied the ultrastructural changes in trachea and lung parenchyma of rats exposed to IQOS stick mainstream and tissue pro-inflammatory markers. We investigated the reactive oxygen species amount along with the markers of tissue and DNA oxidative damage. Moreover, we tested the putative genotoxicity of IQOS mainstream through Ames and alkaline Comet mutagenicity assays. RESULTS: Here, we identified irritating and carcinogenic compounds including aldehydes and polycyclic aromatic hydrocarbons in the IQOS mainstream as sign of incomplete combustion and degradation of tobacco, that lead to severe remodelling of smaller and largest rat airways. We demonstrated that IQOS mainstream induces lung enzymes that activate carcinogens, increases tissue reactive radical concentration; promotes oxidative DNA breaks and gene level DNA damage; and stimulates mitogen activated protein kinase pathway which is involved in the conventional tobacco smoke-induced cancer progression. CONCLUSIONS: Collectively, our findings reveal that IQOS causes grave lung damage and promotes factors that increase cancer risk. IMPLICATIONS: IQOS has been proposed as a safer alternative to conventional cigarettes, due to depressed concentration of various harmful constituents typical of traditional tobacco smoke. However, its lower health risks to consumers have yet to be determined. Our findings confirm that IQOS mainstream contains pyrolysis and thermogenic degradation by-products, the same harmful constituents of traditional cigarette smoke, and, for the first time, we show that it causes grave lung damage and promotes factors that increase cancer risk in the animal model.


Assuntos
Fumaça , Produtos do Tabaco , Animais , DNA , Pulmão , Ratos , Ratos Sprague-Dawley , Fumar , Nicotiana , Produtos do Tabaco/toxicidade
3.
J Water Health ; 18(2): 200-206, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32300092

RESUMO

Effective resin disinfection is mandatory to ensure the microbiological quality of water treated by domestic softeners. The wet and sometimes warm environment inside the softener is ideal for bacteria growth. Our research was focused on the evaluation of the microbial quality of water from softeners sanitized by chlorine solutions or by electrolytic systems. We employed the heterotrophic plate count and specific tests to monitor the presence of opportunistic and pathogenic bacteria (Pseudomonas aeruginosa, Escherichia coli, enterococci, and coliforms). Completely new devices were equipped with a commercially available electrolytic system or with a newly patented one or sanitized by automatic or manual addition of chlorine solutions. In all cases, the contamination was reduced, not completely avoided. In particular, the patented electrolytic system significantly reduced bacterial proliferation in strongly contaminated devices. Our data confirm the difficulties encountered to solve the problem of microbiological quality of softened water and offer encouraging information on new possible solutions.


Assuntos
Cloro , Desinfecção , Microbiologia da Água , Purificação da Água , Bactérias/isolamento & purificação , Contagem de Colônia Microbiana , Eletrólise , Qualidade da Água
4.
Eur J Pharm Sci ; 192: 106650, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37995834

RESUMO

This study investigates the correlation between the structural and release properties of solid lipid microparticles (MPs) of tristearin containing 5 % w/w of four different liquid additives used as crystal modifiers: isopropyl myristate (IM), ethyl oleate (EO), oleic acid (OA) and medium chain triglycerides (MCT). All additives accelerated the conversion of the unstable α-form of tristearin, formed after the MPs manufacturing, to the stable ß-polymorph and the transformation was completed within 24 h (for IM and EO) or 48 h (for OA and MCT). The kinetic of polymorphic transition at 25 °C was investigated by simultaneous synchrotron SAXS/WAXS and DSC analysis after melting and subsequent cooling of the lipid mixture. After crystallization in the α-phase, additives accelerate the solid-solid phase transformation to ß-tristearin. SAXS data showed that two types of structural modifications occurred on MPs during storage: compaction of the crystal packing (slight decrease in lamellar thickness) and crystal growth (increased number of stacked lipid lamellae). The release behavior of a model hydrophilic drug (caffeine) at two different amounts (15 % and 30 %) from MPs was studied in water and biorelevant media simulated the gastric and intestinal environment. It was particularly significant that the introduction of IM, EO and MCT were able to prolong the drug release in water, passing from a diffusion-based Higuchi kinetics to a perfect zero-order kinetic. Moreover, the overall release profiles were higher in biorelevant media, where erosion/digestion of MPs was observed. After 6 months, a moderate but statistically significant change in release profile was observed for the MPs with IM and EO, which can be correlated with the time-dependent structural alterations (i.e. larger average crystallite size) of these formulations; while MPs with OA or MCT displayed stable release profiles. These findings help to understand the correlation between release behavior, polymorphism and supramolecular-level structural modification of lipid formulations containing crystal modifiers.


Assuntos
Água , Liberação Controlada de Fármacos , Espalhamento a Baixo Ângulo , Tamanho da Partícula , Difração de Raios X
5.
Int J Pharm ; 661: 124417, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38964489

RESUMO

Benznidazole (BNZ) serves as the primary drug for treating Chagas Disease and is listed in the WHO Model List of Essential Medicines for Children. Herein, a new child-friendly oral BNZ delivery platform is developed in the form of supramolecular eutectogels (EGs). EGs address BNZ's poor oral bioavailability and provide a flexible twice-daily dose in stick-pack format. This green and sustainable formulation strategy relies on the gelation of drug-loaded Natural Deep Eutectic Solvents (NaDES) with xanthan gum (XG) and water. Specifically, choline chloride-based NaDES form stable and biocompatible 5 mg/mL BNZ-loaded EGs. Rheological and Low-field NMR investigations indicate that EGs are viscoelastic materials comprised of two co-existing regions in the XG network generated by different crosslink distributions between the biopolymer, NaDES and water. Remarkably, the shear modulus and relaxation spectrum of EGs remain unaffected by temperature variations. Upon dilution with simulated gastrointestinal fluids, EGs results in BNZ supersaturation, serving as the primary driving force for its absorption. Interestingly, after oral administration of EGs to rats, drug bioavailability increases by 2.6-fold, with a similar increase detected in their cerebrospinal fluid. The noteworthy correlation between in vivo results and in vitro release profiles confirms the efficacy of EGs in enhancing both peripheral and central BNZ oral bioavailability.


Assuntos
Disponibilidade Biológica , Nitroimidazóis , Polissacarídeos Bacterianos , Animais , Administração Oral , Nitroimidazóis/administração & dosagem , Nitroimidazóis/farmacocinética , Nitroimidazóis/química , Polissacarídeos Bacterianos/química , Masculino , Sistemas de Liberação de Medicamentos/métodos , Ratos , Tripanossomicidas/administração & dosagem , Tripanossomicidas/farmacocinética , Tripanossomicidas/química , Géis , Solventes/química , Ratos Sprague-Dawley , Reologia , Liberação Controlada de Fármacos , Colina/química , Colina/administração & dosagem , Colina/farmacocinética
6.
Front Pharmacol ; 15: 1328917, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38333013

RESUMO

Although the Food and Drug Administration has authorized the marketing of "heat-not-burn" (HnB) electronic cigarettes as a modified risk tobacco product (MRTP), toxicological effects of HnB smoke exposure on the brain are still unexplored. Here, paramagnetic resonance of the prefrontal cortex (PFC) of HnB-exposed rats shows a dramatic increase in reactive radical species (RRS) yield coupled with an inflammatory response mediated by NF-κB-target genes including TNF-α, IL-1ß, and IL-6 and the downregulation of peroxisome proliferator-activated receptor (PPAR) alpha and gamma expression. The PFC shows higher levels of 8-hydroxyguanosine, a marker of DNA oxidative damage, along with the activation of antioxidant machinery and DNA repair systems, including xeroderma pigmentosum group C (XPC) protein complex and 8-oxoguanine DNA glycosylase 1. HnB also induces the expression of drug-metabolizing enzymes such as CYP1A1, CYP2A6, CYP2B6, and CYP2E, particularly involved in the biotransformation of nicotine and several carcinogenic agents such as aldehydes and polycyclic aromatic hydrocarbons here recorded in the HnB stick smoke. Taken together, these effects, from disruption of redox homeostasis, inflammation, PPAR manipulation along with enhanced bioactivation of neurotoxicants, and upregulation of cMYC protooncogene to impairment of primary cellular defense mechanisms, suggest a possible increased risk of brain cancer. Although the HnB device reduces the emission of tobacco toxicants, our findings indicate that its consumption may carry a risk of potential adverse health effects, especially in non-smokers so far. Further studies are needed to fully understand the long-term effects of these devices.

7.
Int J Pharm ; 634: 122696, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36758882

RESUMO

Recently, Natural Deep Eutectic Solvents (NaDES) have emerged as potential solvents for boosting drug bioavailability. In this work, the mechanism of solubility enhancement of some APIs belonging to BCS class II (tolbutamide, nimesulide, domperidone and cinnarizine) in these eutectic bio-solvents was investigated in order to get deeper insights into the molecular interactions between the NaDES components and the selected drugs. Different NaDES formulations based on choline chloride, proline, solid organic acids (citric, tartaric and malic acid), sugars (glucose and xylitol) and water were prepared by mild heating (70 °C). Characterization of unloaded NaDES (pH, Karl Fisher titration, viscosity and FTIR analysis) indicated that the type of Hydrogen Bond Acceptor (HBA) and Hydrogen Bond Donor (HBD), their molar ratio as well as water amount strongly affect the extent of H-bonding interactions. Hard gelatin capsules filled with NaDES maintained their integrity until 6 months, proving that all water molecules participate in H-bond network. APIs' solubility enhancement was significant in all NaDES with respect to buffer solutions (pH 1.2 and 6.8). Analysing NaDES having Choline as HBA, it was found that the solubility of smaller molecules increased using larger HBD, while higher molecular weight APIs can be better inserted into the network formed by smaller HBD. NOE experiments demonstrated the formation of a robust supramolecular structure among the protons of choline, those of organic acid and water. In addition, 1D ROESY spectra revealed for the first time the crucial role of choline (methyl groups) in establishing hydrophobic interactions with the relative aliphatic or aromatic portion of the drugs. These data suggest the complex structure of the API-NaDES supramolecular assembly and underline that drug solubility is dependent on a balance network of H-bonds and hydrophobic interactions as well. Understanding the type of interactions between the API and NaDES is essential for their use as effective solubilisation aid.


Assuntos
Solventes Eutéticos Profundos , Água , Solubilidade , Solventes/química , Água/química , Colina/química
8.
Sci Total Environ ; 789: 148005, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34058583

RESUMO

In this study, a new chemiluminescent method based on the dependence of luminol light emission induced by free radicals in airborne particulate matter (PM) is proposed as a screening assay for the rapid characterization of samples from different sources based on their redox properties. This parameter is considered critical for assessing particulate matter toxicity and its impacts on human health. We propose a cell-free, luminescent assay to evaluate the redox potential of particulate matter directly on the filters employed to collect it. A joint chemometric approach based on Principal Component Analysis and Hotelling Analysis was applied to quickly sort out ambient particulate samples with a significantly different light emission profile caused by Luminol reaction. Based on Spearman correlation analysis, the association of the samples light emission intensity with their chemical composition and emission sources was attempted. The overall methodology was tested with certified reference materials and applied to two series of particulate matter samples previously subjected to thorough chemical speciation and subsequent source apportionment. The results show the effectiveness of the luminescent method, allowing the quick assessment of particulate matter oxidative potential, but providing further evidence on the complexity of the oxidative potential determination in this kind of samples. The chemometric processing of the whole dataset clearly highlights the distinct behavior among the two series of samples, the certificate standard reference materials, and the blank controls, supporting the suitability of the approach.


Assuntos
Poluentes Atmosféricos , Material Particulado , Poluentes Atmosféricos/análise , Humanos , Luminol , Oxirredução , Estresse Oxidativo , Material Particulado/análise
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