|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Department of Anesthesiology, Duke University Medical Center, Durham, NC, USA
2 Department of Neurobiology, Duke University Medical Center, Durham, NC, USA
3 Department of Neurobiology, Duke University Medical Center, Durham, NC, USA; Department of Anesthesiology, Duke University Medical Center, Durham, NC, USA
* To whom correspondence should be addressed. E-mail: sas{at}neuro.duke.edu.
Exposure to airborne particulate matter (PM) is a world-wide health problem mainly because it produces adverse cardiovascular and respiratory effects that frequently result in morbidity. Despite many years of epidemiological and basic research, the mechanisms underlying PM toxicity remain largely unknown. To understand some of these mechanisms, PM-induced apoptosis and necrosis was measured in normal human airway epithelial cells and sensory neurons from both wild type mice and mice lacking TRPV1 receptors using Alexa Fluor 488 conjugated Annexin V and propidium iodide labeling, respectively. Exposure of environmental PMs containing residual oil fly ash and ash from Mt. St. Helens was found to induce apoptosis, but not necrosis, as a consequence of sustained calcium influx through TRPV1 receptors. Apoptosis was completely prevented by inhibiting TRPV1 receptors with capsazepine or by removing extracellular calcium or in sensory neurons from TRPV1-/- mice. Binding of either one of the PMs to the cell membrane induced a capsazepine-sensitive increase in cAMP. However, PM-induced apoptosis was augmented upon the inhibition of PKA. PKA inhibition on its own also induced apoptosis, thereby suggesting that this pathway may be endogenously protective against apoptosis. In summary, it was found that inhibiting TRPV1 receptors prevents PM-induced apoptosis, thereby providing a potential mechanism to reduce their toxicity.
This article has been cited by other articles:
![]() |
B. Nilius, G. Owsianik, T. Voets, and J. A. Peters Transient Receptor Potential Cation Channels in Disease Physiol Rev, January 1, 2007; 87(1): 165 - 217. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. E. Johansen, C. A. Reilly, and G. S. Yost TRPV1 Antagonists Elevate Cell Surface Populations of Receptor Protein and Exacerbate TRPV1-Mediated Toxicities in Human Lung Epithelial Cells Toxicol. Sci., January 1, 2006; 89(1): 278 - 286. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Zhu, Y. Wang, and D. H. Wang Diuresis and Natriuresis Caused by Activation of VR1-Positive Sensory Nerves in Renal Pelvis of Rats Hypertension, October 1, 2005; 46(4): 992 - 997. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Nilius, T. Voets, and J. Peters TRP Channels in Disease Sci. Signal., August 2, 2005; 2005(295): re8 - re8. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. Liedtke and S.A. Simon A possible role for TRPV4 receptors in asthma Am J Physiol Lung Cell Mol Physiol, August 1, 2004; 287(2): L269 - L271. [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |