Source Apportionment of in Vitro Reactive Oxygen Species Bioassay Activity from Atmospheric Particulate Matter

2008 ◽  
Vol 42 (19) ◽  
pp. 7502-7509 ◽  
Author(s):  
Yuanxun Zhang ◽  
James J. Schauer ◽  
Martin M. Shafer ◽  
Michael P. Hannigan ◽  
Steven J. Dutton
Keyword(s):  
Reactive Oxygen Species ◽  
Particulate Matter ◽  
Source Apportionment ◽  
Reactive Oxygen ◽  
Atmospheric Particulate Matter ◽  
Oxygen Species ◽  
Atmospheric Particulate

scholarly journals Airborne particulate matter PM2.5 from Mexico City affects the generation of reactive oxygen species by blood neutrophils from asthmatics: an in vitro approach

2009 ◽  
Vol 4 (1) ◽  
pp. 17 ◽  
Author(s):  
Martha Sierra-Vargas ◽  
Alberto Guzman-Grenfell ◽  
Salvador Blanco-Jimenez ◽  
Jose Sepulveda-Sanchez ◽  
Rosa Bernabe-Cabanillas ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Particulate Matter ◽  
Mexico City ◽  
Reactive Oxygen ◽  
Airborne Particulate Matter ◽  
Oxygen Species ◽  
Airborne Particulate ◽  
Blood Neutrophils

scholarly journals Reactive oxygen species associated with water-soluble PM2.5 in the southeastern United States: spatiotemporal trends and source apportionment

2014 ◽  
Vol 14 (13) ◽  
pp. 19625-19672 ◽  
Author(s):  
V. Verma ◽  
T. Fang ◽  
H. Guo ◽  
L. King ◽  
J. T. Bates ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Particulate Matter ◽  
Source Apportionment ◽  
Biomass Burning ◽  
Reactive Oxygen ◽  
Water Soluble ◽  
Ros Generation ◽  
Emission Sources ◽  
Vehicular Emissions ◽  
Oxygen Species

Abstract. We assess the potential of the water-soluble fraction of atmospheric fine aerosols in the southeastern US 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) in summer, and biomass burning markers in winter. Redox-active metals were also 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 to 25%), while secondary oxidation processes dominated the DTT activity in summer (46%) and biomass burning in winter (47%). Mineral 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. Our results indicate that the ability to generate ROS is a generic property of fine PM to which almost all major emission sources contribute to variable extents. The ubiquitous nature of the ROS generation property of ambient particulate matter suggests widespread population exposures to aerosol components that have the ability to catalyze the production of oxidants in vivo.

scholarly journals The Effects of Bioactive Compounds from Blueberry and Blackcurrant Powder on Oat Bran Pastes: Enhancing In Vitro Antioxidant Activity and Reducing Reactive Oxygen Species in Lipopolysaccharide-Stimulated Raw264.7 Macrophages

Antioxidants ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 388
Author(s):  
Xiao Dan Hui ◽  
Gang Wu ◽  
Duo Han ◽  
Xi Gong ◽  
Xi Yang Wu ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Antioxidant Activity ◽  
Phenolic Compounds ◽  
Antioxidant Capacity ◽  
Bioactive Compounds ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Raw264.7 Macrophages ◽  
Oat Bran

In this study, blueberry and blackcurrant powder were chosen as the phenolic-rich enrichments for oat bran. A Rapid Visco Analyser was used to form blueberry and blackcurrant enriched oat pastes. An in vitro digestion process evaluated the changes of phenolic compounds and the in vitro antioxidant potential of extracts of pastes. The anthocyanidin profiles in the extracts were characterised by the pH differential method. The results showed that blueberry and blackcurrant powder significantly increased the content of phenolic compounds and the in vitro antioxidant capacity of pastes, while the total flavonoid content decreased after digestion compared to the undigested samples. Strong correlations between these bioactive compounds and antioxidant values were observed. Lipopolysaccharide-stimulated RAW264.7 macrophages were used to investigate the intracellular antioxidant activity of the extracts from the digested oat bran paste with 25% enrichment of blueberry or blackcurrant powder. The results indicated that the extracts of digested pastes prevented the macrophages from experiencing lipopolysaccharide (LPS)-stimulated intracellular reactive oxygen species accumulation, mainly by the Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2) signalling pathway. These findings suggest that the bioactive ingredients from blueberry and blackcurrant powder enhanced the in vitro and intracellular antioxidant capacity of oat bran pastes, and these enriched pastes have the potential to be utilised in the development of the functional foods.

scholarly journals Targeting autophagy enhances atezolizumab-induced mitochondria-related apoptosis in osteosarcoma

2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Zhuochao Liu ◽  
Hongyi Wang ◽  
Chuanzhen Hu ◽  
Chuanlong Wu ◽  
Jun Wang ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Antitumor Immunity ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Specific Monoclonal Antibody ◽  
Osteosarcoma Cells ◽  
Jnk Pathway ◽  
In Vivo Experiments

AbstractIn this study, we identified the multifaceted effects of atezolizumab, a specific monoclonal antibody against PD-L1, in tumor suppression except for restoring antitumor immunity, and investigated the promising ways to improve its efficacy. Atezolizumab could inhibit the proliferation and induce immune-independent apoptosis of osteosarcoma cells. With further exploration, we found that atezolizumab could impair mitochondria of osteosarcoma cells, resulting in increased release of reactive oxygen species and cytochrome-c, eventually leading to mitochondrial-related apoptosis via activating JNK pathway. Nevertheless, the excessive release of reactive oxygen species also activated the protective autophagy of osteosarcoma cells. Therefore, when we combined atezolizumab with autophagy inhibitors, the cytotoxic effect of atezolizumab on osteosarcoma cells was significantly enhanced in vitro. Further in vivo experiments also confirmed that atezolizumab combined with chloroquine achieved the most significant antitumor effect. Taken together, our study indicates that atezolizumab can induce mitochondrial-related apoptosis and protective autophagy independently of the immune system, and targeting autophagy is a promising combinatorial approach to amplify its cytotoxicity.

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