Regiani Carvalho-Oliveira

Air pollution and antibodies against modified lipoproteins are associated with atherosclerosis and vascular remodeling in hyperlipemic mice

We analyzed the impact of chronic exposure to urban air pollution on the development of atherosclerosis. Hyperlipemic mice (LDLR(-/-)) were submitted to a high fat diet and air pollution for four months. We measured the susceptibility of LDL to oxidative modifications (TBARS), the presence of anti-oxLDL and an apoB-derived peptide (apoB-D) in blood and the degree of atherosclerosis in the aortic arch. Air pollution increased the susceptibility of LDL to oxidation as well as anti-oxLDL and anti-apo-B levels. These levels were even higher than in mice submitted to a high fat diet and non-polluted air. The lipid content of the atherosclerotic plaques in the aorta was increased in groups with a high cholesterol diet independently of the air quality. However, the thickness of the arterial wall was greater in mice fed a high lipid diet with polluted air. Thus, we conclude that urban air pollution exacerbates the susceptibility of LDL to oxidation, atherogenesis and vascular remodeling in hyperlipemic mice and that an immune response accompanies this process.

Association between micronuclei frequency in pollen mother cells of Tradescantia and mortality due to cancer and cardiovascular diseases: a preliminary study in Sao José dos Campos, Brazil.

The present study was designed to explore the correlation between the frequency of micronuclei in Trad-MN, measured across 28 biomonitoring stations during the period comprised between 11 of May and 2 of October, 2006, and adjusted mortality rates due to cardiovascular, respiratory diseases and cancer in Sao José dos Campos, Brazil, an area with different sources of air pollution. For controlling purposes, mortality rate due to gastrointestinal diseases (an event less prone to be affected by air pollution) was also considered in the analysis. Spatial distribution of micronuclei frequency was determined using average interpolation. The association between health estimators and micronuclei frequency was determined by measures of Pearsons correlation. Higher frequencies of micronuclei were detected in areas with high traffic and close to a petrochemical pole. Significant associations were detected between micronuclei frequency and adjusted mortality rate due to cardiovascular diseases (r=0.841, p=0.036) and cancer (r=0.890, p=0.018). The association between mortality due to chronic obstructive pulmonary diseases was positive but did not reach statistical significance (r=0.640, p=0.172), probably because of the small number of events. Gastrointestinal mortality did not exhibit significant association with micronuclei frequency. Because the small number of observations and the nature of an ecological study, the present findings must be considered with caution and considered as preliminary. Further studies, performed in different conditions of contamination and climate should be done before considering Trad-MN in the evaluation of human health risk imposed by air pollutants.

The time course of vasoconstriction and endothelin receptor A expression in pulmonary arterioles of mice continuously exposed to ambient urban levels of air pollution

The present study aimed to verify the time course of the effects of environmental levels of urban air pollution toxicity on lung arterioles. BALB/c mice (n=56) were continuously exposed to selective chambers equipped with (filtered, F) or without (non-filtered, NF) filter devices for particles and toxic gases for 24h/day, over 14, 21, 30 or 45 days. After exposure, we evaluated the lumen-wall relationship (an estimator of arteriolar narrowing), endothelial nitric oxide synthase (eNOS) and endothelin type A receptor (ETAr) expression in the vascular wall and inflammatory influx of the peribronchiolar area. Concentrations of fine particulate matter (PM<or=2.5 microg/m(3)), nitrogen dioxide (NO(2)), black smoke (BS), humidity and temperature in both the environment and inside the chambers were measured daily. Filters cleared 100% of BS and 97% of PM inside the F chamber. The arteriole wall of the lungs of mice from NF chamber had an increased ETAr expression (p<or=0.042) concomitant to a decrease in the lumen/wall ratio (p=0.02) on the early days of exposure, compared to controls. They also presented a progressive increment of inflammatory influx in the peribronchiolar area during the study (p=0.04) and decrement of the eNOS expression on the 45th day of exposure in both vascular layers (p<or=0.03). We found that after 14 days of exposure, the ambient levels of air pollutants in Sao Paulo induced vasoconstriction that was associated with an increase in ETAr expression. These vascular results do not appear to be coupled to the progressive inflammatory influx in lung tissue, suggesting a down-regulation of vasoconstrictive mechanisms through an imbalance in the cytokines network. It is likely that these responses are protective measures that decrease tissue damage brought about by continuous exposure to air pollutants.

Effects of Chronic Exposure to Air Pollution from Sao Paulo City on Coronary of Swiss Mice, from Birth to Adulthood

To explore the hypothesis that air pollution promotes cardiovascular changes, Swiss mice were continuously exposed, since birth, in two open-top chambers (filtered and nonfiltered for airborne particles ≤ 0.3 μm) placed 20 m from a street with heavy traffic in downtown Sao Paulo, twenty-four hours per day for four months. Fine particle (PM2.5) concentration was determined gravimetrically; hearts were analyzed by morphometry. There was a reduction of the PM2.5 inside the filtered chamber (filtered = 8.61±0.79 μg/m3, nonfiltered = 18.05±1.25 μg/m3, p < .001). Coronary arteries showed no evidence of luminal narrowing in the exposed group but presented higher collagen content in the adventitia of LV large-sized and RV midsized vessels (p = .001) and elastic fibers in both tunicae adventitia and intima-media of almost all sized arterioles from both ventricles (p = .03 and p = .001, respectively). We concluded that chronic exposure to urban air since birth induces mild but significant vascular structural alterations in normal individuals, presented as coronary arteriolar fibrosis and elastosis. These results might contribute to altered vascular response and ischemic events in the adulthood.

In vitro mucus transportability, cytogenotoxicity, and hematological changes as non-destructive physiological biomarkers in fish chronically exposed to metals.

The biomonitoring of fish using biomarkers represents a useful tool for the assessment of aquatic pollution. This study evaluated the sublethal toxic effects of aquatic pollution on fish collected from a site contaminated by metals. Water and fish (Oreochromis niloticus) samples were collected from a pond in the Parque Ecológico do Tietê (PET) that lies along the Tietê River (São Paulo, Brazil), and from a control site (an experimental fish farm). The metal content of the water was evaluated, and fish were used to examine the properties of gill mucus and blood. The PET fish were evaluated for alterations in the in vitro transportability of mucus and changes in blood properties (e.g., cell volume, hemoglobin concentration, red blood cells, and white blood cell count). The results of the water analyzes indicated metal levels above the legal standards for Fe (0.71 mg/L), Ni (0.06 mg/L), Mn (0.11 mg/L), and Pb (0.48 mg/L). Compared to the controls, the hematologic parameter analyzes of PET fish revealed significantly higher numbers of erythrocytes (RBC), leukocytes (WBC), lymphocytes, erythroblasts, and Mean Corpuscular Volume (MCV); however, the hemoglobin content and Mean Corpuscular Hemoglobin Concentration (MCHC) values were significantly lower. The frequencies of nuclear abnormalities and micronuclei were significantly higher and the mucociliary transport was significantly lower in PET fish than in the controls. These results suggest that fish from the contaminated site exhibit a series of physiological responses, which probably indicate health disturbances. Furthermore, the results suggest that blood and mucus are promising, non-destructive targets for use in the monitoring of pollution.

Effectiveness of traffic-related elements in tree bark and pollen abortion rates for assessing air pollution exposure on respiratory mortality rates

The majority of epidemiological studies correlate the cardiorespiratory effects of air pollution exposure by considering the concentrations of pollutants measured from conventional monitoring networks. The conventional air quality monitoring methods are expensive, and their data are insufficient for providing good spatial resolution. We hypothesized that bioassays using plants could effectively determine pollutant gradients, thus helping to assess the risks associated with air pollution exposure. The study regions were determined from different prevalent respiratory death distributions in the Sao Paulo municipality. Samples of tree flower buds were collected from twelve sites in four regional districts. The genotoxic effects caused by air pollution were tested through a pollen abortion bioassay. Elements derived from vehicular traffic that accumulated in tree barks were determined using energy-dispersive X-ray fluorescence spectrometry (EDXRF). Mortality data were collected from the mortality information program of Sao Paulo City. Principal component analysis (PCA) was applied to the concentrations of elements accumulated in tree barks. Pearson correlation and exponential regression were performed considering the elements, pollen abortion rates and mortality data. PCA identified five factors, of which four represented elements related to vehicular traffic. The elements Al, S, Fe, Mn, Cu, and Zn showed a strong correlation with mortality rates (R2>0.87) and pollen abortion rates (R2>0.82). These results demonstrate that tree barks and pollen abortion rates allow for correlations between vehicular traffic emissions and associated outcomes such as genotoxic effects and mortality data.

Aerobic exercise in polluted urban environments: effects on airway defense mechanisms in young healthy amateur runners

In this study, the effects of aerobic exercise on the upper airways and their defense mechanisms were investigated in athletes. The athletes ran in two different environments: the downtown streets of the city of São Paulo (Street), more polluted, and an urban forest (Forest), less polluted. Thirty-eight young healthy athletes ran for 45 min d-1 randomly during five consecutive days, with an interval of 48 h before changing environment. Clinical parameters and respiratory tract defense markers were evaluated before and after the first run on Mondays (1 d) and on Fridays (5 d). Street presented higher mean PM2.5 concentrations (65.1  ±  39.1 µg m-3, p  <  0.001) and lower temperature (22.0 °C, p  =  0.010) than Forest (22.6  ±  15.3 µg m-3 and 22.8 °C). After 1 d Street running, subjects showed an increment in heart rate (p  <  0.001). At day 5, there was twice the number of athletes with impaired nasal mucociliary clearance (MCC) in the Street runners group when compared to the Forest runners group. Exhaled breath condensate pH values increased in the Forest group, with significant differences between groups in day 1 (p  =  0.006) and day 5 (p  <  0.001), despite the fact that both groups showed values within the normal range. After exposure to both environments, the number of cells in the nasal lavage fluid was reduced after exercise (p  =  0.014), without alterations in cell type and IL-8 and IL-10 concentrations. Aerobic exercise can either maintain or acutely enhance MCC and it may help to regulate inflammatory responses in the airways. Here we show that exercise practice in polluted outdoor environment, over a 5 d period, impairs MCC. In contrast, athletes running in the less polluted environment (Forest) show higher exhaled breath condensate pH values when compared to those who exercised in a more polluted environment (Street).

Metal embryotoxicity from urban particles in Sao Paulo city: An experimental study in chicken embryos

Chicken eggs were inoculated with suspensions of ambient air particles (<or=10 microm, PM10) from Sao Paulo city in 3, 0.3 or 0.03 microg doses on one of the four early days of embryo development. On the eleventh day of development alterations were observed on embryos inoculated with PM10 3 microg on the third day. Particles analysis showed high content of metals. Hence, embryos were also inoculated with PM10 (3 microg) combined with metal chelating EDTA. PM10 (3 microg) embryos presented underdevelopment (stage 29.44+/-11.4) compared to vehicle and positive controls (stage 36.44+/-0.51 Saline and stage 31.20+/-9.7 Cyclophosphamide, p<or=0.05); higher (47%) mortality rate (23% Saline and 42% Cyclophosphamide) and low (68%) viability (100% Saline and 70% Cyclophosphamide, p=0.04). Effects were attenuated when embryos received PM10+EDTA (stage 33.63+/-0.94, 18.9% mortality rate and 82% viability). PM10 from Sao Paulo city is embryotoxic and metal may be implicated in the toxic mechanism.

Chemical composition modulates the adverse effects of particles on the mucociliary epithelium

OBJECTIVE: We compared the adverse effects of two types of real ambient particles; i.e., total suspended particles from an electrostatic precipitator of a steel mill and fine air particles from an urban ambient particulate matter of 2.5 µm, on mucociliary clearance. METHOD: Mucociliary function was quantified by mucociliary transport, ciliary beating frequency and the amount of acid and neutral mucous in epithelial cells through morphometry of frog palate preparations. The palates were immersed in one of the following solutions: total suspended particles (0.1 mg/mL), particulate matter 2.5 µm 0.1 mg/mL (PM0.1) or 3.0 mg/mL (PM3.0) and amphibian Ringers solution (control). Particle chemical compositions were determined by X-ray fluorescence and gas chromatography/mass spectrometry. RESULTS: Exposure to total suspended particles and PM3.0 decreased mucociliary transport. Ciliary beating frequency was diminished by total suspended particles at all times during exposure, while particulate matter of 2.5 µm did not elicit changes. Particulate matter of 2.5 µm reduced epithelial mucous and epithelium thickness, while total suspended particles behaved similarly to the control group. Total suspended particles exhibited a predominance of Fe and no organic compounds, while the particulate matter 2.5 µm contained predominant amounts of S, Fe, Si and, to a lesser extent, Cu, Ni, V, Zn and organic compounds. CONCLUSION: Our results showed that different compositions of particles induced different airway epithelial responses, emphasizing that knowledge of their individual characteristics may help to establish policies aimed at controlling air pollution.

Four Years of Experience with the Sao Paulo University Medical School Community Garden

The School of Medicine, Sao Paulo University Community Garden (FMUSP Community Garden), formed in June 2013, occupies an area of 520 m2. In the concreted area, vegetables and herbs are grown in large vessels (http://www.facebook.com/HortaDaFmusp). The garden runs on an agroecological basis using locally made compost (garden leaves and horse manure) and bio fertilizers provided by volunteers and the local restaurant (coffee powder). In the garden several herbs, medicinal plants, wild food plants and different types of seasonal vegetables are cultivated. The harvest is open for the entire community. Five medical students received financial support from the University to work 40 h per month to maintain the FMUSP Community Garden. Educational activities for the community include workshops (on medicinal herbs and wild food plants) and cooking events with students and volunteers including an elderly group, focused on healthy eating. In addition, a Ph.D. student conducted studies addressing the role of air pollution on urban gardens using the garden as an experimental site. In summary, the FMUSP Community Garden has provided sustainable, educational and research activities focused on sustainability and healthy eating in the medical campus, on a low budget, for the community. We believe this paper is important because it describes how this experience has benefited many health-related professionals and complements medical teaching. The FMUSP Community Garden has shown that agriculture in large urban centers is possible. The results were very promising, involving students, staff, patients and the surrounding community.