Navigation Links
Nicotine drives cell invasion that contributes to plaque formation in coronary arteries
Date:12/15/2013

Nicotine, the major addictive substance in cigarette smoke, contributes to smokers' higher risk of developing atherosclerosis, the primary cause of heart attacks, according to research to be presented Sunday, Dec. 15, at the American Society for Cell Biology Annual Meeting in New Orleans.

These findings suggest that e-cigarettes, the battery-powered devices that deliver nicotine in steam without the carcinogenic agents of tobacco smoke, may not significantly reduce smokers' risk for heart disease, said Chi-Ming Hai, Ph.D., of Brown University.

E-cigarettes have put nicotine back in the news and into the hands of a growing number of U.S. smokers who now "vape," that is, inhale a steam of nicotine, polyethylene glucose (PEG) and flavoring generated by cigarette-shaped vaporizers.

Alhough e-cigarettes are being promoted as "safe" nicotine delivery systems, the safety of nicotine has been disputed, partly because the mechanism by which it acts on the circulatory system has not been well understood.

Dr. Hai's research on human and rat vascular smooth muscle cells provides evidence of a link between nicotine and atherosclerosis.

In Dr. Hai's experiments, nicotine appeared to drive the formation of a kind of cellular drill called podosome rosettes, which are members of the invadosome family, consisting of invadopodia, podosomes and podosome rosettes. These specialized cell surface assemblies degrade and penetrate the tissue during cell invasion. Invasion of vascular smooth muscle cells from the middle layer of the arterial wall (media) to the inner layer of the arterial wall (intima) contributes substantially to plaque formation in atherosclerosis.

Dr. Hai subjected rat and primary human vascular smooth muscle cells to prolonged (six hours) nicotine treatment, enabling the cells to form podosome rosettes in response to Protein Kinase C (PKC) activation, which controls protein phosphorylation in signal transduction cascades. The podosome rosettes set the scene for global extracellular matrix degradation and internalization. PKC activation alone, that is, without nicotine treatment, could induce the formation of podosomes in the rat muscle cells, accompanied by focal extracellular matrix degradation.

Nicotinic acetylcholine receptors, which bind neurotransmitters, co-localized with other podosome markers (vinculin, PKC-alpha, and metalloproteinase-2) at podosomes and podosome rosettes in the rat cells.

Matrigel-coated transwell experiments indicated that nicotine treatment and PKC activation worked synergistically to enhance invasiveness in the primary human vascular smooth muscle cells. Inclusion of alpha-bungarotoxin, a nicotinic acetylcholine receptor antagonist, or cycloheximide, a protein synthesis inhibitor, during nicotine treatment abolished nicotine-induced podosome rosette formation in the rat cells, suggesting that signaling through the nicotinic acetylcholine receptors and synthesis of new proteins are required for podosome rosette formation.

Altogether the data from the studies of rat and primary human vascular smooth muscle cells suggest that nicotine enhances vascular smooth muscle cell invasion by activating synergistic mechanisms between the nicotinic acetylcholine receptor and PKC signaling.

According to Dr. Hai, a potential clinical implication of these findings is that replacing cigarette smoking by nicotine administration may not bring much benefit to lowering the risk of developing atherosclerosis. Still, Dr. Hai said that he believes that understanding the synergistic mechanisms between nicotinic acetylcholine receptor and PKC in vascular smooth muscle invasion may lead to new therapeutics for minimizing the damaging effects of nicotine on the vascular system.


'/>"/>

Contact: Cathy Yarbrough
cyarbrough@ascb.org
858-243-1814

John Fleischman
jfleischman@ascb.org

American Society for Cell Biology
Source:Eurekalert


Related biology news :

1. An early spring drives butterfly population declines
2. TLR1 protein drives immune response to certain food-borne illness in mice
3. AACR news: Studies show increasing evidence that androgen drives breast cancer
4. NREL drives toward the future with fuel cell EVs
5. Environment drives genetics in Evolution Canyon; discovery sheds light on climate change
6. Preventing home invasions means fighting side-by-side for coral-dwelling crabs and shrimp
7. Professors Antarctica research shows potential king crab invasion
8. Fox invasion threatens wave of extinction, UC research finds
9. Study turns parasite invasion theory on its head
10. Invasion of the slugs -- halted by worms...
11. Land management options outlined to address cheatgrass invasion
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/11/2017)... , April 11, 2017 Crossmatch®, ... secure authentication solutions, today announced that it has ... Advanced Research Projects Activity (IARPA) to develop next-generation ... program. "Innovation has been a driving ... Thor program will allow us to innovate and ...
(Date:4/6/2017)... -- Forecasts by Product Type (EAC), Biometrics, ... (Transportation & Logistics, Government & Public Sector, Utilities / ... Facility, Nuclear Power), Industrial, Retail, Business Organisation (BFSI), Hospitality ... looking for a definitive report on the $27.9bn Access ... ...
(Date:4/4/2017)... NEW YORK , April 4, 2017   ... solutions, today announced that the United States Patent and ... The patent broadly covers the linking of an iris ... the same transaction) and represents the company,s 45 th ... our latest patent is very timely given the multi-modal ...
Breaking Biology News(10 mins):
(Date:10/10/2017)... CA (PRWEB) , ... October ... ... a development-stage cancer-focused pharmaceutical company advancing targeted antibody-drug conjugate (ADC) therapeutics, today ... of targeted HPLN (Hybrid Polymerized Liposomal Nanoparticle), a technology developed in collaboration ...
(Date:10/10/2017)... ... October 10, 2017 , ... ... process optimization firm for the life sciences and healthcare industries, announces a presentation ... San Francisco. , The presentation, “Automating GxP Validation for Agile Cloud Platforms,” will ...
(Date:10/9/2017)... ... 2017 , ... The Giving Tree Wellness Center announces the ... of consumers who are incorporating medical marijuana into their wellness and health regimens. ... operators of two successful Valley dispensaries, The Giving Tree’s two founders, Lilach Mazor ...
(Date:10/6/2017)... Boston, Mass. (PRWEB) , ... October 06, 2017 ... ... spotlight female entrepreneurship within the healthcare and technology sector at their fourth annual ... six panels featuring 30 inspiring speakers and the ELEVATE pitch competition showcasing early ...
Breaking Biology Technology: