Secondhand Smoking Is Associated With Vascular Inflammation.
BACKGROUND
The relative risk for cardiovascular diseases in passive smokers is similar to that of active smokers despite almost a 100-fold lower dose of inhaled cigarette smoke. However, the mechanisms underlying the surprising susceptibility of the vascular tissue to the toxins in secondhand smoke (SHS) have not been directly investigated. The aim of this study was to investigate directly vascular endothelial cell function in passive smokers.


METHODS
Using a minimally invasive method of endothelial biopsy, we investigated directly the vascular endothelium in 23 healthy passive smokers, 25 healthy active smokers, and 23 healthy control subjects who had never smoked and had no regular exposure to SHS. Endothelial nitric oxide synthase (eNOS) function (expression of basal eNOS and activated eNOS [phosphorylated eNOS at serine1177 (P-eNOS)]) and expression of markers of inflammation (nuclear factor-κB [NF-κB]) and oxidative stress (nitrotyrosine) were assessed in freshly harvested venous endothelial cells by quantitative immunofluorescence.


RESULTS
Expression of eNOS and P-eNOS was similarly reduced and expression of NF-κB was similarly increased in passive and active smokers compared with control subjects. Expression of nitrotyrosine was greater in active smokers than control subjects and similar in passive and active smokers. Brachial artery flow-mediated dilation was similarly reduced in passive and active smokers compared with control subjects, consistent with reduced endothelial NO bioavailability.


CONCLUSIONS
Secondhand smoking increases vascular endothelial inflammation and reduces active eNOS to a similar extent as active cigarette smoking, indicating direct toxic effects of SHS on the vasculature.
Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians and Surgeons, New York, NY.
Tessa
T
Adams
Division of Cardiology, Columbia University College of Physicians and Surgeons, New York, NY.
Elaine
E
Wan
Division of Biostatistics, Columbia University College of Physicians and Surgeons, New York, NY.
Ying
Y
Wei
Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians and Surgeons, New York, NY.
Romina
R
Wahab
Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians and Surgeons, New York, NY.
Francesco
F
Castagna
Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians and Surgeons, New York, NY.
Gang
G
Wang
Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians and Surgeons, New York, NY.
Memet
M
Emin
Division of Cardiology, Columbia University College of Physicians and Surgeons, New York, NY.
Cesare
C
Russo
Division of Cardiology, Columbia University College of Physicians and Surgeons, New York, NY.
Shunichi
S
Homma
Section of Cardiology, Tulane University School of Medicine, New Orleans, LA.
Thierry H
TH
Le Jemtel
Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians and Surgeons, New York, NY.
Sanja
S
Jelic
D000328:Adult; D001916:Brachial Artery / Q000502:physiology; D016022:Case-Control Studies; D003367:Cotinine / Q000097:blood; D042783:Endothelial Cells / Q000378:metabolism* / Q000473:pathology; D004730:Endothelium, Vascular / Q000378:metabolism* / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D016328:NF-kappa B / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology; D012907:Smoking / Q000009:adverse effects / Q000378:metabolism / Q000473:pathology*; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism; D014664:Vasodilation / Q000502:physiology; D055815:Young Adult
D016328:NF-kappa B; D014028:Tobacco Smoke Pollution; C002744:3-nitrotyrosine; D014443:Tyrosine; D052250:Nitric Oxide Synthase Type III; D003367:Cotinine