Skip directly to search Skip directly to A to Z list Skip directly to page options Skip directly to site content

NIOSHTIC-2 Publications Search

Search Results

Hemoglobin potentiates the production of reactive oxygen species by alveolar macrophages.

Authors
Huffman-LJ; Miles-PR; Shi-X; Bowman-L
Source
Exp Lung Res 2000 Apr-May; 26(3):203-217
NIOSHTIC No.
20020704
Abstract
The objectives of this investigation were (1) to determine the effects of hemoglobin on the production of reactive oxygen species by activated rat alveolar macrophages, (2) to determine a possible mechanism for these effects, and (3) to determine which part of the hemoglobin molecule is responsible for these effects. Production of reactive oxygen species by phorbol myristate acetate (PMA)-stimulated cells was assessed by measuring luminol-enhanced chemiluminescence (CL). Hemoglobin enhances PMA-stimulated CL in a dose-dependent manner. The effect is maximal at 0.5-1.0 microM hemoglobin where PMA-induced CL is increased by approximately 20-fold. Superoxide anion release from PMA-stimulated cells is not affected by hemoglobin. However, the hemoglobin-induced enhancement of PMA-stimulated CL is inhibited by superoxide dismutase, catalase, dimethylthiourea, or deferoxamine. These results suggest that hydroxyl radical may be formed from hydrogen peroxide which is derived from superoxide anion. Measurements of electron spin resonance spectra following spin trapping of radicals verify that hydroxyl radicals are produced by the cells in the presence of PMA and hemoglobin. The hemoglobin effects appear to require iron in a protoporphyrin complex, because hemin stimulates PMA-induced CL, whereas neither ferrous nor ferric iron has any effect. These findings taken together suggest that hemoglobin can act as a biological Fenton reagent to enhance the production of reactive oxygen species from alveolar macrophages and potentially contribute to lung damage during leakage of blood into the alveolar spaces.
Keywords
Acetates; Hydroxy-compounds; Lung-disorders; Pulmonary-system-disorders; Respiratory-system-disorders; Blood-disorders; Author Keywords: Electron Spin Resonance; Fenton Reagent
Contact
Linda J. Huffman, PhD, NIOSH, HELD/M/S 2015, 1095 Willowdale Raod, Morgantown, WV 26505, USA
CODEN
EXLRDA
CAS No.
7722-84-1
Publication Date
20000401
Document Type
Journal Article
Email Address
ljh3@cdc.gov
Fiscal Year
2000
NTIS Accession No.
NTIS Price
Issue of Publication
3
ISSN
0190-2148
NIOSH Division
HELD
Source Name
Experimental Lung Research
State
WV
TOP