Changes in F-Actin Organization Induced by Hard Metal Particle Exposure in Rat Pulmonary Epithelial Cells Using Laser Scanning Confocal Microscopy

Details

• Personal Author:
  Antonini JM ; Millecchia LL ; Rao KMK ; Roberts, Jennifer R. ; Starks K ; Yang HM
• Description:
  Chronic inhalation of hard metal (WC-Co) particles causes alveolitis and the eventual development of pulmonary fibrosis. The initial inflammatory response includes a change in the alveolar epithelial cell-capillary barrier, which has been shown to be regulated by the state of assembly and organization of the actin cytoskeletal network. The objective of this study was to evaluate the effect WC-Co particles have on F-actin organization of lung epithelial cells in an in vitro culture system. Rat lung epithelial (L2) cells were exposed to 5, 25, and 100 microg/mL of WC-Co particles, as well as the individual components (Co and WC) of the hard metal mixture particles for 24 h. The effect on F-actin organization was visualized by laser scanning confocal microscopy (LSCM) following Bodipy-Phallacidin staining. Minimal changes in the F-actin microfilaments of L2 cells were observed by LSCM after exposure to WC and WC-Co at 5 and 25 microg/mL, while at 100 microg/mL, there was a noticeable disruption in the uniform distribution of L2 cell F-actin microfilaments. After exposure to Co, a dose-dependent change in the F-actin organization of the L2 cells was observed. Little change in F-actin assembly was observed after treatment with 5 microg/mL of Co (the concentration equivalent to the 5% amount of Co commonly present in 100 microg/mL of the WC-Co sample mixture). However, at 100 microg/mL of Co, the microfilaments aggregated into homogeneous masses within the cells, and a significant loss in the organization of L2 F-actin was observed. These dramatic alterations in F-actin organization seen after exposure to the higher doses of Co were attributed to an increase in L2 cell injury as measured by lactate dehydrogenase and trypan blue exclusion. We conclude the pulmonary response evoked in the lung by inhalation of high levels of WC-Co particles is unlikely due to alterations in the F-actin microfilaments of lung-epithelial cells. [Description provided by NIOSH]
• Subjects:
  Animals Environmental Exposure Fibrosis Laboratories Lung Lung Diseases Metals Occupational Health Respiratory System Respiratory Tract Diseases Safety

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• Keywords:
  Animal Studies Exposure Levels Inhalation Studies Laboratory Animals Lung Cells Lung Fibrosis Microscopy Pulmonary System Disorders Respiratory System Disorders
• ISSN:
  1097-9336
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HELD - Health Effects Laboratory Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  5-16
• Volume:
  13
• Issue:
  1
• NIOSHTIC Number:
  nn:20020606
• Citation:
  In Vitr Mol Toxicol 2000 Apr; 13(1):5-16
• Email:
  jga6@cdc.gov
• Federal Fiscal Year:
  2000
• Peer Reviewed:
  True
• Source Full Name:
  In Vitro and Molecular Toxicology
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:5e510a0e6a8133c961d07f9f202f57238972ce8b506b309ff1c9acd4d65c38c16222bf9b9ad783bd78336fb3799bd86d10995bda41d01c016e3cdbed5bd8ee15
• Download URL:
  https://stacks.cdc.gov/view/cdc/198306/cdc_198306_DS1.pdf
• File Type:
  [PDF - 6.67 MB ]