title: Apoptotic and inflammatory effects induced by different particles in human alveolar macrophages.
abstract: Pollutant particles induce apoptosis and inflammation, but the relationship between these two biological processes is not entirely clear. In this study, we compared the proapoptotic and proinflammatory effects of four particles: residual oil fly ash (ROFA), St. Louis particles SRM 1648 (SL), Chapel Hill PM10 (CHP), and Mount St. Helens dust (MSH). Human alveolar macrophages (AM) were incubated with these particles at 100 microg/ml. Cell death was assessed by annexin V (AV) expression, histone release, nuclear morphology, caspase 3-like activity and release of caspase 1 for apoptosis, and propidium iodide (PI) for necrosis, and inflammation was measured by interleukin (IL)-1beta and IL-6. We found that particle effects on these cell death measurements varied, and ROFA affected most (four out of five) endpoints, including nuclear morphological changes. CHP and SL also caused necrosis. For cytokine release, the potency was CHP > SL > ROFA > MSH. The proapoptotic and proinflammatory effects induced by the whole particles were unaltered after the particles were washed with water. The water-soluble fraction was relatively inactive, as were individual soluble metals (V, Ni, Fe). ROFA-induced nuclear fragmentation was associated with upregulation and mitochondrial release of apoptosis-inducing factor (AIF), a caspase-independent chromatin condensation factor, and upregulation of DNase II, a lysosomal acid endonuclease. These results indicate that the potential for particles to induce apoptosis does not correlate with their proinflammatory properties, although active components for both processes reside in the water-insoluble core. Both apoptosis and inflammatory endpoints should be included when the toxicity of different pollutant particles is assessed.
authors.affiliation: National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, Chapel Hill, North Carolina, USA. huang.tony@epa.gov
authors.forename: Yuh-Chin T
authors.initials: YC
authors.lastname: Huang
authors.forename: Zhuowei
authors.initials: Z
authors.lastname: Li
authors.forename: Shirley D
authors.initials: SD
authors.lastname: Harder
authors.forename: Joleen M
authors.initials: JM
authors.lastname: Soukup
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D017304:Annexin A5 / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D002244:Carbon / Q000633:toxicity; D020170:Caspase 1 / Q000378:metabolism; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002467:Cell Nucleus / Q000187:drug effects / Q000473:pathology; D002947:Cities; D060729:Coal Ash; D006657:Histones / Q000378:metabolism; D006801:Humans; D007220:Industrial Waste / Q000009:adverse effects; D007375:Interleukin-1 / Q000096:biosynthesis*; D015850:Interleukin-6 / Q000096:biosynthesis*; D016676:Macrophages, Alveolar / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D010316:Particle Size; D052638:Particulate Matter; D018707:Volcanic Eruptions / Q000009:adverse effects
chemical_list: D000393:Air Pollutants; D017304:Annexin A5; D060729:Coal Ash; D006657:Histones; D007220:Industrial Waste; D007375:Interleukin-1; D015850:Interleukin-6; D052638:Particulate Matter; D002244:Carbon; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases; D020170:Caspase 1