Source Impacts on and Cardiorespiratory Effects of Reactive Oxygen Species Generated by Water-Soluble PM2.5 Across the Eastern United States

Author(s):  
Josephine T. Bates ◽  
Rodney J. Weber ◽  
Joseph Abrams ◽  
Vishal Verma ◽  
Ting Fang ◽  
...  
2014 ◽  
Vol 14 (23) ◽  
pp. 12915-12930 ◽  
Author(s):  
V. Verma ◽  
T. Fang ◽  
H. Guo ◽  
L. King ◽  
J. T. Bates ◽  
...  

Abstract. We assess the potential of the water-soluble fraction of atmospheric fine aerosols in the southeastern United States to generate reactive oxygen species (ROS) and identify major ROS-associated emission sources. ROS-generation potential of particles was quantified by the dithiothreitol (DTT) assay and involved analysis of fine particulate matter (PM) extracted from high-volume quartz filters (23 h integrated samples) collected at various sites in different environmental settings in the southeast, including three urban-Atlanta sites, in addition to a rural site. Paired sampling was conducted with one fixed site in Atlanta (Jefferson Street), representative of the urban environment, with the others rotating among different sites, for ~250 days between June 2012 and September 2013 (N=483). A simple linear regression between the DTT activity and aerosol chemical components revealed strong associations between PM ROS-generation potential and secondary organic aerosol (WSOC – water-soluble organic carbon) in summer, and biomass burning markers in winter. Redox-active metals were also somewhat correlated with the DTT activity, but mostly at urban and roadside sites. Positive matrix factorization (PMF) was applied to apportion the relative contribution of various sources to the ROS-generation potential of water-soluble PM2.5 in urban Atlanta. PMF showed that vehicular emissions contribute uniformly throughout the year (12–25%), while secondary oxidation processes dominated the DTT activity in summer (46%) and biomass burning in winter (47%). Road dust was significant only during drier periods (~12% in summer and fall). Source apportionment by chemical mass balance (CMB) was reasonably consistent with PMF, but with higher contribution from vehicular emissions (32%). Given the spatially large data set of PM sampled over an extended period, the study reconciles the results from previous work that showed only region- or season-specific aerosol components or sources contributing to PM ROS activity, possibly due to smaller sample sizes. The ubiquitous nature of the major sources of PM-associated ROS suggests widespread population exposures to aerosol components that have the ability to catalyze the production of oxidants in vivo.


Author(s):  
Ekaterina Kovel ◽  
Anna Sachkova ◽  
Natalia Vnukova ◽  
Grigoriy Churilov ◽  
Elena Knyazeva ◽  
...  

Fullerenols are nanosized water-soluble polyhydroxylated derivatives of fullerenes, specific allotropic form of carbon, bioactive compounds and perspective pharmaceutical agents. We studied biological effects of a series of fullerenols. Antioxidant activity and toxicity of the fullerenols were compared using bioluminescence assays (cellular and enzymatic); a content of Reactive Oxygen Species in fullerenol solutions was determined using chemiluminescence luminol method. Two groups of fullerenols with different number of hydroxyl substituents were under investigation: (I) С60Оy(OH)x, С60,70Оy(OH)x, where х+у=24–28 and (II) С60,70Оy(OH)x, Fe0,5С60Оy(OH)x, where х+у=40–42. Toxicity of the fullerenols was evaluated using effective concentrations ЕС50. Fullerenol’ antioxidant activity was investigated in model solutions of organic toxicant of oxidative type, 1,4-benzoquinone. Detoxification coefficients were calculated to analyze and compare the antioxidant activity. Higher toxicity and lower antioxidant activity were demonstrated in the solutions of fullerenols with higher number of the oxygen substituents (х+у=40–42). The differences were concerned with fullerenol’ ability to disturb Reactive Oxygen Species balance in aqueous solutions. Toxic effect of the prospective endohedral metal-fullerenol with gadolinium atom involved, Gd@C82Oy(OH)x, where х+у=40–42, was evaluated and explained by a high number of oxygen groups


2010 ◽  
Vol 128 (10) ◽  
pp. 2481-2494 ◽  
Author(s):  
Rajasubramaniam Shanmugam ◽  
Praveen Kusumanchi ◽  
Hitesh Appaiah ◽  
Liang Cheng ◽  
Peter Crooks ◽  
...  

2001 ◽  
Vol 85 (4) ◽  
pp. 431-440 ◽  
Author(s):  
Karla Kovary ◽  
Tatiana S. Louvain ◽  
Maria C. Costa e Silva ◽  
Franco Albano ◽  
Barbara B. M. Pires ◽  
...  

Naturally occurring antioxidants such as carotenoids are extensively studied for their potential in reducing the risk for cancer and other chronic diseases. In the present study, the radical-scavenger activity of the food additive norbixin, a water-soluble carotenoid extracted fromBixa orellanaseeds and commercialized as annatto, was evaluated under conditions of DNA damage induced by reactive oxygen species, particularly by hydroxyl radicals. The cell-free scavenger activity of norbixin was evaluated using plasmid DNA as target molecule and Sn2+or Fe2+as oxidant. The addition of H2O2enhanced DNA breakage induced by metal ions, particularly Fe2+. Under these conditions, norbixin started to protect plasmid DNA against single- and double-strand breakage at a metal:norbixin ratio of 1:1 (Sn2+) and 1:10 (Fe2+). However, at lower ratios to Sn2+, norbixin enhanced Sn2+-induced DNA breakage (P<0.05). The ability of norbixin to protect genomic DNA against oxidative damage was assessed in murine fibroblasts submitted to H2O2-induced oxidative stress and the results were evaluated by the comet assay. Under low serum conditions (2 % fetal bovine serum (FBS)), a protective effect of norbixin against H2O2-induced DNA breakage was inversely related to its concentration, a protection ranging from 41 % (10 μM) TO 21 % (50 μm). At higher concentrations of norbixin, however, oxidative DNA breakage was still enhanced, even in the presence of a high serum concentration (10 % FBS). Under normal conditions, norbixinper sehas no detectable genotoxic or cytotoxic effects on murine fibroblasts. The antimutagenic potential of norbixin against oxidative mutagens was also evaluated by theSalmonella typhimuriumassay, with a maximum inhibition of 87 % against the mutagenicity induced by H2O2. Although plasmid DNA and Ames data indicated that norbixin can protect DNA against oxidative damage, it seems to be a risky guardian of genomic DNA as it can also increase the extent of oxidative damage.


2009 ◽  
Vol 56 (4) ◽  
Author(s):  
Dorota Dymkowska ◽  
Lech Wojtczak

Arachidonic acid at micromolar concentrations produced a drastic increase of the generation of reactive oxygen species (ROS) in rat hepatoma AS-30D cells cultivated in vitro along with an increase in the incidence of apoptotic cell death. Both processes were prevented by trolox, a water-soluble tocopherol derivative, and tempol, a known antioxidative agent. A synthetic hybrid of lipoic acid and trolox or preincubation with N-acetylcysteine were less effective. Preincubation of the cells with etomoxir, a known highly specific irreversible inhibitor of carnitine-palmitoyltransferase I, partly decreased the ROS formation induced by arachidonic acid but it did not affect the increase in apoptosis. Cumulatively, these results indicate that apoptosis induced in hepatoma cells by arachidonic acid is mediated by ROS. They also suggest that this effect is due to arachidonic acid as such and not to its mitochondrial oxidative metabolites.


Sign in / Sign up

Export Citation Format

Share Document