1,721,145 research outputs found
Toxicological aspects associated with Electronic Nicotine Delivery System (ENDS) consumption
No full textTobacco smoking remains a leading cause of premature death worldwide. In combination with conventional smoking cessation protocols, Electronic Nicotine Delivery Systems (ENDS) (including the e-cigarette and the newest heat-not-burn devices) have been proposed as a useful smoking cessation tool. Although the levels of toxicants in the mainstream are significantly lower than those observed in tobacco smoke, our research team raised some concerns about the alleged health risk associated with their use. Our studies show the co-mutagenic and cancer-initiating effects of ENDS exposure in rat lung. We found that ENDS produce extensive DNA damage in leukocytes measured by the comet assay as well as increased rate of micronuclei formation in reticulocytes. Furthermore, electron microscopy images indicate severe remodeling of the smaller and larger airways.
ENDS exposure increases oxidative stress in the prefrontal cortex with an increased level of 8-hydroxyguanosine, a reliable marker of DNA oxidation positively associated with smoking habit. Consistently, xeroderma pigmentosum group C protein complex and 8-oxoguanine DNA glycosylase-1 (OGG-1), two crucial proteins involved in major DNA repair pathways were found upregulated in exposed animals. ENDS can induce neuroinflammation through activation of the NF-κB signaling pathway and the down-regulation of PPARα and PPARγ as negative regulators of inflammation.
Interestingly, ENDS affect male gonadal function by increasing markers of oxidative stress including those associated with DNA damage, as well as NF-kB dependent pro-inflammatory mediators; inactivation of key androgenic enzymes such as 3β-hydroxysteroid dehydrogenase (3β-HSD) and 17β-hydroxysteroid dehydrogenase (17β-HSD), together with reduced testosterone synthesis suggest, potential impairment of male gonadal function.
Collectively, our findings reveal that ENDS consumption mimics some pathological mechanisms typically triggered by conventional cigarettes suggesting caution in proposing them as a healthy alternative to smoking or as an aid to smoking cessation especially in young people and pregnant wome
Effects of chlorinated drinking water on the xenobiotic metabolism in Cyprinus carpio treated with samples from two Italian municipal networks
No full textDrinking water (DW) disinfection represents a milestone of the past century, thanks to its efficacy in the reduction of risks of epidemic forms by water micro-organisms. Nevertheless, such process generates disinfection by-products (DBPs), some of which are genotoxic both in animals and in humans and carcinogenic in animals. At present, chlorination is one of the most employed strategies but the toxicological effects of several classes of DBPs are unknown. In this investigation, a multidisciplinary approach foreseeing the chemical analysis of chlorinated DW samples and the study of its effects on mixed function oxidases (MFOs) belonging to the superfamily of cytochrome P450-linked monooxygenases of Cyprinus carpio hepatopancreas, was employed. The experimental samples derived from aquifers of two Italian towns (plant 1, river water and plant 2, spring water) were obtained immediately after the disinfection (A) and along the network (R1). Animals treated with plant 1 DW-processed fractions showed a general CYP-associated MFO induction. By contrast, in plant 2, a complex modulation pattern was achieved, with a general up-regulation for the point A and a marked MFO inactivation in the R1 group, particularly for the testosterone metabolism. Together, the toxicity and co-carcinogenicity (i.e. unremitting over-generation of free radicals and increased bioactivation capability) of DW linked to the recorded metabolic manipulation, suggests that a prolonged exposure to chlorine-derived disinfectants may produce adverse health effects
Harmful effects behind the daily supplementation of a fixed vegetarian blend in the rat model
No full textFruit and vegetables (FV) have long been considered a panacea against major chronic diseases, including cancer. However, there is no convincing epidemiological, clinical or experimental evidence supporting FV chemopreventive ability. A daily mono-supplementation of lyophilized onion, tomato, peach, black grape or lettuce was compared with the daily combined administration of the same FV (5 a day-like diet). Ten days post-treatment, the phase-I/II xenobiotic metabolizing and antioxidant enzyme activities, protein and mRNA levels were investigated. As a marker of oxidative stress, the level of hydroperoxides was measured in rat serum samples. Here we show that a blend of FV orally administered to rats not only potentially manipulates metabolism but also disrupts systemic oxidative homeostasis. A daily combination of the five servings remarkably down-regulates the catalytic activity, protein and mRNA levels of a cohort of hepatic metabolizing enzymes, suggesting a possible depressed clearance upon exposure to ubiquitous carcinogens. Strikingly, we observed an impairment of antioxidant enzymes with a boost in systemic hydroperoxide levels. Our study identifies new potential factors of cancer risk connected with the persistent consumption of fixed servings of FV, suggesting that dietary guidance should rely on a “daily diversification” of FV
Peroxisome proliferators activated receptors gamma and the inflammatory state of gastric mucosa
No full textComparison between in toto peach (Prunus persica L. Batsch) supplementation and its polyphenolic extract on rat liver xenobiotic metabolizing enzymes
No full textOver the past years, there has been a growing interest in the natural constituents of foods as a potential means of cancer control. To date, epidemiology studies seem to indicate an inverse association between regular consumption of fruit and vegetables and cancer risk. Here, the potential chemopreventive activity of the polyphenolic extract (PPE) of peach (Prunus persica L. Batsch) and of the freeze-dried fruit in toto (LFT), focusing on the modulation of xenobiotic metabolizing enzymes (XMEs) in vivo, was investigated. Rats were daily supplemented with LFT at 250 and 500 mg/kg b.w. or with the corresponding amount of PPE (2.5 and 5 mL/kg b.w., respectively) for either 7 or 14 days. While PPE treatment resulted in a widespread phase-I inactivation, a complex modulation pattern with drastic decreases (7α-testosterone hydroxylase, pentoxyresorufin O-dealkylase (PROD)), coupled with marked up-regulations of ethoxyresorufin O-deethylase (EROD) and methoxyresorufin O-demethylase (MROD) after LFT administration, was seen. A notable down-regulation (over 50%) following LFT or PPE treatment for the phase-II enzymes was also recorded. The observed remarkable changes in XMEs, if reproduced in humans, might have public health implications. These data suggest caution in promoting peach fruit (mono-diet) consumption or its polyphenolic extract in the field of chemoprevention
Modulazione della superfamiglia CYP in Dreissena polymorpha esposte ad acqua del Lago Trasimeno trattata con differenti disinfettanti.
Full text linkCardiac homeostasis imbalanced following chronic exposure to mainstream emission of a heated tobacco product
No full textToxicological Aspects Associated with Consumption from Electronic Nicotine Delivery System (ENDS): Focus on Heavy Metals Exposure and Cancer Risk
Full text linkTobacco smoking remains one of the leading causes of premature death worldwide. Electronic Nicotine Delivery Systems (ENDSs) are proposed as a tool for smoking cessation. In the last few years, a growing number of different types of ENDSs were launched onto the market. Despite the manufacturing differences, ENDSs can be classified as “liquid e-cigarettes” (e-cigs) equipped with an atomizer that vaporizes a liquid composed of vegetable glycerin (VG), polypropylene glycol (PG), and nicotine, with the possible addition of flavorings; otherwise, the “heated tobacco products” (HTPs) heat tobacco sticks through contact with an electronic heating metal element. The presence of some metals in the heating systems, as well as in solder joints, involves the possibility that heavy metal ions can move from these components to the liquid, or they can be adsorbed into the tobacco stick from the heating blade in the case of HTPs. Recent evidence has indicated the presence of heavy metals in the refill liquids and in the mainstream such as arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni), copper (Cu), and lead (Pb). The present review discusses the toxicological aspects associated with the exposition of heavy metals by consumption from ENDSs, focusing on metal carcinogenesis risk
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