Urinary oxidative stress biomarkers in nephrotoxicity induced by PM in a rat model.

Objective: The present study evaluated urinary oxidative stress (OxS) biomarkers to explain the extrapulmonary effect of renal function decline due to subchronic inhalation exposure to particles smaller than 2.5 μm, as well as the correlation of the biomarkers with the particles' endotoxin content.

Materials And Methods: Adult male Sprague-Dawley rats were exposed to subchronic inhalation of particles smaller than 2.

Fine particulate matter and intima media thickness: Role of endothelial function biomarkers.

Background: Ambient fine particulate matter (PM) is a risk factor for atherosclerosis disease. We aimed to assess whether nitric oxide stable metabolites (NOx) and l-arginine mediate the association between PM and carotid intima media thickness (cIMT) increase.

Methods: We selected 251 participants from the control group of GEA (Genetics of Atheroslerosis Disease Mexican) study (2008-2013) in Mexico City.

Toxicological effects of solvent-extracted organic matter associated with PM on human bronchial epithelial cell line NL-20.

The heterogeneity and complexity of solvent-extracted organic matter associated with PM (SEOM-PM) is well known; however, there is scarce information on its biological effects in human cells. This work aimed to evaluate the effect of SEOM-PM collected in northern Mexico City during the cold-dry season (November 2017) on NL-20 cells, a human bronchial epithelial cell line. The SEOM obtained accounted for 15.

Aluminum enhances the oxidative damage of ZnO NMs in the human neuroblastoma SH-SY5Y cell line.

Bare and doped zinc oxide nanomaterials (ZnO NMs) are of great interest as multifunctional platforms for biomedical applications. In this study, we systematically investigate the physicochemical properties of Aluminum doped ZnO (AZO) and its bio-interactions with neuroblastoma (SH-SY5Y) and red blood (RBCs) cells. We provide a comprehensive chemical and structural characterization of the NMs.

Long-term exposure to ambient fine particulate matter and carotid intima media thickness at bilateral, left and right in adults from Mexico City: Results from GEA study.

Background: PM exposure has been associated with intima-media thickness (cIMT) increase. However, very few studies distinguished between left and right cIMT in relation to PM exposure.

Aim: To evaluate associations between chronic exposure to PM and cIMT at bilateral, left, and right in adults from Mexico City.

Subchronic co-exposure to particulate matter and fructose-rich-diet induces insulin resistance in male Sprague Dawley rats.

Insulin resistance (IR) and metabolic disorders are non-pulmonary adverse effects induced by fine particulate matter (PM) exposure. The worldwide pandemic of high fructose sweeteners and fat rich modern diets, also contribute to IR development. We investigated some of the underlying effects of IR, altered biochemical insulin action and Insulin/AKT pathway biomarkers.

Effect of subchronic exposure to ambient fine and ultrafine particles on rat motor activity and striatal dopaminergic transmission.

Alterations in dopaminergic transmission are associated with neurological disorders, such as depression, autism, and Parkinson's disease. Exposure of rats to ambient fine (FP) or ultrafine (UFP) particles induces oxidative and inflammatory responses in the striatum, a neuronal nucleus with dense dopaminergic innervation and critically involved in the control of motor activity. We used an system to evaluate the effect of inhalation exposure to FP and UFP on motor activity and dopaminergic transmission.

PM induces airway hyperresponsiveness and inflammation via the AhR pathway in a sensitized Guinea pig asthma-like model.

Exposure to fine particulate matter (PM) induces airway inflammation and hyperreactivity that lead to asthma. The mechanisms involved are still under investigation. We investigated the effect of resveratrol (3,4',5-trihydroxystilbene) (RES) on airway hyperresponsiveness, inflammation and CYP1A1 protein expression (an aryl hydrocarbon receptor (AhR) target) induced by PM exposure in an allergic asthma experimental guinea pig model.

Acute kidney damage by PM exposure in a rat model.

PM exposure is associated with a glomerular filtration rate (GFR) reduction, and renal tissue damage. The goal of this study was demonstrate the acute effect of PM on the kidney. Male rats were acutely exposed to PM or filtered air.

In vitro exposure to ambient fine and ultrafine particles alters dopamine uptake and release, and D receptor affinity and signaling.

The exposure to environmental pollutants, such as fine and ultrafine particles (FP and UFP), has been associated with increased risk for Parkinson's disease, depression and schizophrenia, disorders related to altered dopaminergic transmission. The striatum, a neuronal nucleus with extensive dopaminergic afferents, is a target site for particle toxicity, which results in oxidative stress, inflammation, astrocyte activation and modifications in dopamine content and D receptor (DR) density. In this study we assessed the in vitro effect of the exposure to FP and UFP on dopaminergic transmission, by evaluating [H]-dopamine uptake and release by rat striatal isolated nerve terminals (synaptosomes), as well as modifications in the affinity and signaling of native and cloned DRs.

Comparative effects of TiO and ZnO nanoparticles on growth and ultrastructure of ovarian antral follicles.

Titanium dioxide (TiO) and zinc oxide (ZnO) nanoparticles (NP) have been demonstrated to reach the ovary. However, the potential detrimental effects of these metal-based NP on ovarian antral follicles and whether they can be directly taken up by follicular cells are unknown. The aim of this study was to evaluate whether TiO and ZnO NP internalize into the antral follicle, and further compared any potential detrimental effects of either NP on growth, ultrastructure and viability of antral follicles.

Survival Mechanisms and Xenobiotic Susceptibility of Keratinocytes Exposed to Metal-Derived Nanoparticles.

Metal-derived nanoparticles (Mt-NPs) are increasingly used in cosmetology due to their ultraviolet shielding (titanium dioxide [TiO]), antioxidant (cerium dioxide [CeO]), and biocidal (silver [Ag]) properties. In the absence of overt toxicity (i.e.

In utero exposure to ultrafine particles promotes placental stress-induced programming of renin-angiotensin system-related elements in the offspring results in altered blood pressure in adult mice.

Background: Exposure to particulate matter (PM) is associated with an adverse intrauterine environment, which can promote adult cardiovascular disease (CVD) risk. Ultrafine particles (UFP) (small size and large surface area/mass ratio) are systemically distributed, induce inflammation and oxidative stress, and have been associated with vascular endothelial dysfunction and arterial vasoconstriction, increasing hypertension risk. Placental stress and alterations in methylation of promoter regions of renin-angiotensin system (RAS)-related elements could be involved in UFP exposure-related programming of hypertension.

Effect of in vivo exposure to ambient fine particles (PM) on the density of dopamine D-like receptors and dopamine-induced [S]-GTPγS binding in rat prefrontal cortex and striatum membranes.

Male Sprague-Dawley rats (8-9 weeks-old) were exposed for three days (acute exposure) or eight weeks (subchronic exposure) to purified air or concentrated ambient fine particles, PM (≤2.5 μm; 15 to 18-fold of ambient air; 370-445 μg/m). In membranes from rat prefrontal cortex (PFC) or striatum, the density and function of dopamine D-like receptors (DRs) were assessed by [H]-spiperone binding and dopamine-stimulated [S]-GTPγS binding, respectively.

Synthesis, Characterization and In Vitro Study of Synthetic and Bovine-Derived Hydroxyapatite Ceramics: A Comparison.

The physicochemical properties and biological behavior of sintered-bovine-derived hydroxyapatite (BHAp) are here reported and compared to commercial synthetic-HAp (CHAp). Dense ceramics were sintered for 2 h and 4 h at 1200 °C to investigate their microstructure-structure-in-vitro behavior relationship for both HAp ceramics. Densification was directly proportional to sintering time, showing a grain coarsening behavior with a greater effect on BHAp.

Nanomaterials Versus Ambient Ultrafine Particles: An Opportunity to Exchange Toxicology Knowledge.

Background: A rich body of literature exists that has demonstrated adverse human health effects following exposure to ambient air particulate matter (PM), and there is strong support for an important role of ultrafine (nanosized) particles. At present, relatively few human health or epidemiology data exist for engineered nanomaterials (NMs) despite clear parallels in their physicochemical properties and biological actions in models.

Objectives: NMs are available with a range of physicochemical characteristics, which allows a more systematic toxicological analysis.

Inhalation of concentrated PM from Mexico City acts as an adjuvant in a guinea pig model of allergic asthma.

Exposure to Particulate Matter (PM) could function as an adjuvant depending on the city of origin in mice allergic asthma models. Therefore, our aim was to determine whether inhalation of fine particles (PM2.5) from Mexico City could act as an adjuvant inducing allergic sensitization and/or worsening the asthmatic response in guinea pig, as a suitable model of human asthma.

Regulation of human GDNF gene expression in nigral dopaminergic neurons using a new doxycycline-regulated NTS-polyplex nanoparticle system.

The human glial-cell derived neurotrophic factor (hGDNF) gene transfer by neurotensin (NTS)-polyplex nanoparticles functionally restores the dopamine nigrostriatal system in experimental Parkinson's disease models. However, high levels of sustained expression of GDNF eventually can cause harmful effects. Herein, we report an improved NTS-polyplex nanoparticle system that enables regulation of hGDNF expression within dopaminergic neurons.

Increased methylation of repetitive elements and DNA repair genes is associated with higher DNA oxidation in children in an urbanized, industrial environment.

DNA methylation in DNA repair genes participates in the DNA damage regulation. Particulate matter (PM), which has metals and polycyclic aromatic hydrocarbons (PAHs) adsorbed, among others has been linked to adverse health outcomes and may modify DNA methylation. To evaluate PM exposure impact on repetitive elements and gene-specific DNA methylation and DNA damage, we conducted a cross-sectional study in 150 schoolchildren (7-10 years old) from an urbanized, industrial area of the metropolitan area of Mexico City (MAMC), which frequently exhibits PM concentrations above safety standards.

TNFα and IL-6 Responses to Particulate Matter in Vitro: Variation According to PM Size, Season, and Polycyclic Aromatic Hydrocarbon and Soil Content.

Background: Observed seasonal differences in particulate matter (PM) associations with human health may be due to their composition and to toxicity-related seasonal interactions.

Objectives: We assessed seasonality in PM composition and in vitro PM pro-inflammatory potential using multiple PM samples.

Methods: We collected 90 weekly PM10 and PM2.

Acute and subchronic exposure to air particulate matter induces expression of angiotensin and bradykinin-related genes in the lungs and heart: Angiotensin-II type-I receptor as a molecular target of particulate matter exposure.

Background: Particulate matter (PM) adverse effects on health include lung and heart damage. The renin-angiotensin-aldosterone (RAAS) and kallikrein-kinin (KKS) endocrine systems are involved in the pathophysiology of cardiovascular diseases and have been found to impact lung diseases. The aim of the present study was to evaluate whether PM exposure regulates elements of RAAS and KKS.

The effect of composition, size, and solubility on acute pulmonary injury in rats following exposure to Mexico city ambient particulate matter samples.

Particulate matter (PM)-associated metals can contribute to adverse cardiopulmonary effects following exposure to air pollution. The aim of this study was to investigate how variation in the composition and size of ambient PM collected from two distinct regions in Mexico City relates to toxicity differences. Male Wistar Kyoto rats (14 wk) were intratracheally instilled with chemically characterized PM10 and PM2.

Carotid intima-media thickness and plasma asymmetric dimethylarginine in Mexican children exposed to inorganic arsenic.

Background: Arsenic exposure is a risk factor for atherosclerosis in adults, but there is little information on arsenic and early risk biomarkers for atherosclerosis in children. Carotid intima-media thickness (cIMT) is an indicator of subclinical atherosclerotic burden that has been associated with plasma asymmetric dimethylarginine (ADMA), a predictor of cardiovascular disease risk.

Objectives: The aim of this study was to investigate associations of arsenic exposure with cIMT, ADMA, and endothelial adhesion molecules [soluble intercellular cell adhesion molecule-1 (sICAM-1); soluble vascular cell adhesion molecule-1 (sVCAM-1)] in children who had been exposed to environmental inorganic arsenic (iAs).

Variation in the composition and in vitro proinflammatory effect of urban particulate matter from different sites.

Spatial variation in particulate matter-related health and toxicological outcomes is partly due to its composition. We studied spatial variability in particle composition and induced cellular responses in Mexico City to complement an ongoing epidemiologic study. We measured elements, endotoxins, and polycyclic aromatic hydrocarbons in two particle size fractions collected in five sites.

Distributed lag associations between respiratory illnesses and mortality with suspended particle concentration in Tula, a highly polluted industrial region in Central Mexico.

Purpose: We aimed to evaluate the association between changes in airborne particulate matter concentration (PM) with changes in cases of mortality, acute respiratory infections (ARI) and asthma over 2004-2008 in an industrialized and polluted region in central Mexico.

Methods: A generalized linear model with a Poisson distribution and a negative binomial analysis was used to evaluate the influence of PM and temperature on all-cause mortality (All-cause-M), cause-specific mortality (Cause-specific-M), ARI and asthma, using cubic spline functions and distributed lags of PM. Estimated changes in relative risk were calculated for an exposure corresponding to each increase of 10 μg/m(3) in PM level.