Inactivation of plasma alpha1-proteinase inhibitor by aldehydes found in cigarette smoke.
SAAS Bull: Biochem Biotechnol 1990 Jan; 3():32-36
The effects of some carbonyl compounds found in cigarette smoke on the proteinase inhibitory activity of alpha1-proteinase-inhibitor (API) and unfractionated plasma were investigated. When API was incubated with increasing concentrations of acrolein (107028) for up to 120 minutes, elastase inhibitory capacity (EIC) and trypsin inhibitory capacity (TIC) were reduced. About 35% and 75% of EIC were lost at acrolein concentrations of 10 millimolar (mM) and 40mM, respectively. Increasing acrolein to 100mM resulted in total loss of EIC instantaneously. The rate of loss of TIC was similar to EIC, but the decrease in EIC was greater. Whole plasma reacted with acrolein showed a decrease of 50% and 60% for TIC and EIC, respectively, at 100mM acrolein. When API was incubated with pyruvic-aldehyde, 10% of EIC and TIC were lost. It required 400mM pyruvic-aldehyde (78988) to inactivate API 90% in plasma. Incubation of API with 200mM glyoxal (107222) caused 25 to 30% loss of EIC or TIC. In whole plasma, 500mM glyoxal caused 15% reduction in EIC and 30% reduction of TIC. Loss of EIC by acrolein was dependent on disappearance of lysine and histidine residues, which was in turn dependent on concentration of acrolein. The authors conclude that all three aldehydes inactivated API, with acrolein being the most potent. The findings suggest that aldehydes may play a role in pulmonary emphysema, which results from the proteolytic action of elastases on lung elastin.
NIOSH-Grant; Grants-other; In-vitro-study; Acyclic-aldehydes; Blood-plasma; Enzyme-inhibitors; Cigarette-smoking; Tobacco-smoke
Human Biol Chem and Genetics University of Texas Med BR Dept of Human Biol Chem&gene Galveston, Tex 77550-2774
107-02-8; 78-98-8; 107-22-2
Other Occupational Concerns; Grants-other
SAAS Bulletin: Biochemistry and Biotechnology
University of Texas Medical Branch, Galveston, Texas