TY - JOUR
T1 - Modification of human LDL by in vitro incubation with cigarette smoke or copper ions
T2 - Implications for allergies, asthma and atherosclerosis
AU - Vruwink, Kimberly G.
AU - Gershwin, M. Eric
AU - Sachet, Paul
AU - Halpern, Georges
AU - Davis, Paul A.
PY - 1996/9
Y1 - 1996/9
N2 - Cigarette smoking has been linked to a higher risk of not only atherosclerosis and related diseases, but asthma and allergies as well. The mechanisms linking smoking to these diseases may be due in part to increased low density lipoprotein (LDL) modification. In the current study, we compared the modification in vitro of LDL isolated from healthy volunteers that had been exposed to either the gas phase of cigarette smoke or copper ion mediated oxidation. The study used as measures of modification/damage the levels of protein carbonyl groups, changes in electrophoretic mobility on agarose gel electrophoresis and levels of thiobarbituric-reacting substances. Other measures used to assess other aspects of LDL modification included SDS PAGE and immunoblotting. Both copper ion or exposure to the gas phase of cigarette smoke increased electrophoretic mobility of LDL but the increase was greater in the gas phase smoke group. In contrast, thiobarbituric reacting substance levels were increased primarily in copper oxidized LDL. Protein carbonyl levels were increased to a similar extent in both copper ion and smoke exposed samples. Addition of EDTA prevented the modifications found upon copper mediated oxidation of LDL, but EDTA did not prevent the modification of the gas phase cigarette smoke exposed LDL. In summary, the results indicate that protein carbonyl formation can be used as a measure of the modification of LDL particles and, using several different assessment techniques, there are distinct differences in the modified LDL produced by in vitro incubation with gas phase cigarette smoke relative to that found upon incubation of LDL with copper ion. The in vitro smoking-produced LDL. modifications may potentially be relevant to the process of lipoprotein modification in vivo and to the subsequent biological effects of these modified lipoproteins on processes affected by the immune system involvement, such as atherosclerosis and allergy/asthma.
AB - Cigarette smoking has been linked to a higher risk of not only atherosclerosis and related diseases, but asthma and allergies as well. The mechanisms linking smoking to these diseases may be due in part to increased low density lipoprotein (LDL) modification. In the current study, we compared the modification in vitro of LDL isolated from healthy volunteers that had been exposed to either the gas phase of cigarette smoke or copper ion mediated oxidation. The study used as measures of modification/damage the levels of protein carbonyl groups, changes in electrophoretic mobility on agarose gel electrophoresis and levels of thiobarbituric-reacting substances. Other measures used to assess other aspects of LDL modification included SDS PAGE and immunoblotting. Both copper ion or exposure to the gas phase of cigarette smoke increased electrophoretic mobility of LDL but the increase was greater in the gas phase smoke group. In contrast, thiobarbituric reacting substance levels were increased primarily in copper oxidized LDL. Protein carbonyl levels were increased to a similar extent in both copper ion and smoke exposed samples. Addition of EDTA prevented the modifications found upon copper mediated oxidation of LDL, but EDTA did not prevent the modification of the gas phase cigarette smoke exposed LDL. In summary, the results indicate that protein carbonyl formation can be used as a measure of the modification of LDL particles and, using several different assessment techniques, there are distinct differences in the modified LDL produced by in vitro incubation with gas phase cigarette smoke relative to that found upon incubation of LDL with copper ion. The in vitro smoking-produced LDL. modifications may potentially be relevant to the process of lipoprotein modification in vivo and to the subsequent biological effects of these modified lipoproteins on processes affected by the immune system involvement, such as atherosclerosis and allergy/asthma.
KW - Antioxidants
KW - Asthma
KW - Copper ions
KW - Gas phase cigarette smoke
KW - Oxidized LDL
KW - Protein carbonyl
KW - TBARS
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M3 - Article
C2 - 8959540
AN - SCOPUS:0029800477
VL - 6
SP - 294
EP - 300
JO - Journal of Investigational Allergology and Clinical Immunology
JF - Journal of Investigational Allergology and Clinical Immunology
SN - 1018-9068
IS - 5
ER -