Moller, Winifred, Brown, David M, Kreyling, Lofgang and Stone, Vicki (2005) Ultrafine particles cause cytoskeletal dysfunctions in macrophages: role of intracellular calcium. Particle and Fibre Toxicology, 2 (1). p. 7.Full text not available from this repository. (Request a copy)
Particulate air pollution is reported to cause adverse health effects in susceptible individuals. Since most of these particles are derived form combustion processes, the primary composition product is carbon with a very small diameter (ultrafine, less than 100 nm in diameter). Besides the induction of reactive oxygen species and inflammation, ultrafine particles (UFP) can cause intracellular calcium transients and suppression of defense mechanisms of alveolar macrophages, such as impaired migration or phagocytosis.
In this study the role of intracellular calcium transients caused by UFP was studied on cytoskeleton related functions in J774A.1 macrophages. Different types of fine and ultrafine carbon black particles (CB and ufCB, respectively), such as elemental carbon (EC90), commercial carbon (Printex 90), diesel particulate matter (DEP) and urban dust (UD), were investigated. Phagosome transport mechanisms and mechanical cytoskeletal integrity were studied by cytomagnetometry and cell viability was studied by fluorescence microscopy. Macrophages were exposed in vitro with 100 and 320 μg UFP/ml/million cells for 4 hours in serum free medium. Calcium antagonists Verapamil, BAPTA-AM and W-7 were used to block calcium channels in the membrane, to chelate intracellular calcium or to inhibit the calmodulin signaling pathways, respectively.
Impaired phagosome transport and increased cytoskeletal stiffness occurred at EC90 and P90 concentrations of 100 μg/ml/million cells and above, but not with DEP or UD. Verapamil and W-7, but not BAPTA-AM inhibited the cytoskeletal dysfunctions caused by EC90 or P90. Additionally the presence of 5% serum or 1% bovine serum albumin (BSA) suppressed the cytoskeletal dysfunctions. Cell viability showed similar results, where co-culture of ufCB together with Verapamil, W-7, FCS or BSA produced less cell dead compared to the particles only.
|Uncontrolled Keywords:||Ultrafine particles; Cytoskeleton; Stiffness; Viscoelasticity; Phagosome transport; Relaxation; Intracellular calcium|
|University Divisions/Research Centres:||Faculty of Health, Life & Social Sciences > School of Life Sciences|
|Dewey Decimal Subjects:||600 Technology > 610 Medicine & health > 612 Human physiology|
600 Technology > 610 Medicine & health > 611 Human anatomy, cytology & histology
600 Technology > 610 Medicine & health > 614 Incidence & prevention of disease
|Library of Congress Subjects:||Q Science > QP Physiology|
Q Science > QM Human anatomy
|Depositing User:||RAE Import|
|Date Deposited:||20 Jun 2008 14:32|
|Last Modified:||11 Feb 2011 13:56|
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