Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Smoking damages key regulatory enzyme in the lung

07.09.2005


Smoking appears to reduce a key enzyme in the lungs, possibly contributing to some of smoking’s deleterious health effects, according to a study published in the September issue of the Journal of Nuclear Medicine. The study, which used a radiotracer to track the enzyme, also shows that smokers had a lower concentration of the tracer in the bloodstream than nonsmokers did, leading to speculation that smokers and nonsmokers may respond differently to a variety of substances administered by inhalation or intravenously, including therapeutic, anesthetic and addictive drugs.



“The effects of smoking on human health are enormous; yet, little is known about the pharmacologic effects of smoking on the human body apart from the effects of nicotine,” noted Joanna S. Fowler, Ph.D., program director of the Brookhaven Center for Translational Neuroimaging in Upton, N.Y. Researchers from Brookhaven National Laboratory, the National Institute on Drug Abuse and the State University of New York at Stony Brook used positron emission tomography (PET) scanning and a tracer chemical that binds to a specific form of the enzyme monoamine oxidase (MAO A) to track MAO A levels in both smokers and nonsmokers. With whole-body PET imaging, researchers could measure the concentration and movement of the radiotracer and MAO A, a subtype of the enzyme crucial to mood regulation and one that breaks down chemical compounds that elevate blood pressure, said the Society of Nuclear Medicine member.

In the study, “Comparison of Monoamine Oxidase A in Peripheral Organs in Nonsmokers and Smokers,” researchers traced the MAO A subtype in nine smokers and nine nonsmokers, discovering that MAO A was fairly well “intact” in all of the peripheral organs except in smokers’ lungs, said Fowler. Smokers had MAO A levels that were 50 percent lower than in nonsmokers, she said, noting that a prior study had also shown a significant reduction of MAO A in smokers’ brains.


MAO A breaks down many compounds that affect blood pressure, and the lung is a major metabolic organ in degrading some of these compounds, Fowler said. So reduced levels of MAO A in smokers’ lungs may be a significant factor contributing to some of the physiological effects of smoking, including changes in blood pressure and pulmonary function.

Smokers’ lungs also held onto the tracer chemical much longer than nonsmokers, and the delivery of tracer into the arterial blood supply was much lower for smokers, particularly for the first few minutes after being injected, Fowler added. This finding could imply that smokers and nonsmokers respond differently to other substances that enter the body via the bloodstream, including therapeutic drugs, anesthetics, abused substances and environmental agents—even nicotine.

Cigarette smoking, “the most damaging of all addictive substances,” remains the leading cause of preventable death and has negative health impacts on people at all stages of life, said Fowler, and has been in the headlines recently with the death of ABC “World News Tonight” anchorman Peter Jennings. Cigarette smoking accounts for 440,000 deaths each year in the United States, or nearly one of every five deaths, according to the Centers for Disease Control and Prevention. Smoking kills more Americans than AIDS, illegal drugs, alcohol, car accidents, suicides and murders combined and increases one’s chances of developing lung, bladder, esophageal and throat cancers; chronic lung diseases; and coronary heart and cardiovascular diseases.

Fowler and her colleagues have been studying MAO for more than 30 years. The U.S. Department of Energy (DOE) Office of Biological and Environmental Research and the National Institutes of Health have provided funding for this study, said Fowler. She added, “It’s important that the public know about the benefits derived from the DOE’s long-term investments in basic science—especially in radioisotope and radiotracer chemistry and imaging physics—that have played such an important role in introducing new nuclear medicine procedures into the practice of health care.”

“Comparison of Monoamine Oxidase A in Peripheral Organs in Nonsmokers and Smokers” appears in the September issue of the Journal of Nuclear Medicine, which is published by the Society of Nuclear Medicine. Fowler co-authored the article with Jean Logan, Ph.D., Colleen Shea, M.S., Victor Garza, M.S., Youwen Xu, M.S., Yu-Shin Ding, Ph.D., David Alexoff, BSE, and Donald Warner, all with Brookhaven National Laboratory’s chemistry department; Gene-Jack Wang, M.D., Frank Telang, M.D., Noelwah Netusil, RN, Pauline Carter, RN, Millard Jayne, RN, Payton King, M.S, and Paul Vaska, Ph.D., all with Brookhaven National Laboratory’s Medical Department; Nora D. Volkow, M.D., National Institute on Drug Abuse, Bethesda, Md.; Wei Zhu, Ph.D., Department of Applied Mathematics and Statistics, State University of New York at Stony Brook; and Dinko Franceschi, M.D., Department of Radiology, State University of New York at Stony Brook.

Maryann Verrillo | EurekAlert!
Further information:
http://www.snm.org

More articles from Life Sciences:

nachricht Microscope measures muscle weakness
16.11.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg

nachricht Good preparation is half the digestion
16.11.2018 | Max-Planck-Institut für Stoffwechselforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Purdue cancer identity technology makes it easier to find a tumor's 'address'

16.11.2018 | Health and Medicine

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>