News / Health

Study: Your Lungs Can Smell

A new study says your lungs can sense odors, but that they do so much differently from your nose. (Via Flickr)
A new study says your lungs can sense odors, but that they do so much differently from your nose. (Via <a href="http://www.flickr.com/photos/liverpoolhls/">Flickr</a>)

Related Articles

US Panel: Some Current, Former Smokers Should Get Annual Lung Scans

Under the Affordable Care Act, insurers will be required to cover the screenings

Study: Tobacco Tax Hike Could Save 200 Million Lives

Tripling tobacco taxes would decrease worldwide consumption by about a third, the study said

Study: Chinese Plant Ingredient Eases Chronic Pain

Compound comes from roots of flowering Corydalis herb which Chinese have used for centuries for its analgesic qualities
VOA News
Your lungs can smell. That’s what new research suggests.

But unlike the odor receptors in your nose, which send a message to the brain, the receptors in your lung cause the airways to constrict when a pungent or caustic odor such as cigarette smoke is sensed.

The new class of cells, called pulmonary neuroendocrine cells, or PNECs, were discovered by scientists at Washington University in St. Louis and the University of Iowa.

“Our body plan is a tube within a tube, so our lungs and our gut are open to the external environment,” said Yehuda Ben-Shahar, an assistant professor of biology and of medicine at Washington University in St. Louis.  “Although they’re inside us, they’re actually part of our external layer. So they constantly suffer environmental insults,” he said, “and it makes sense that we evolved mechanisms to protect ourselves.”

The researchers say the cells might be responsible for the chemical hypersensitivity that characterizes respiratory diseases, such as chronic obstructive pulmonary disease (COPD) and asthma. Patients with these diseases are told to avoid traffic fumes, pungent odors, perfumes and similar irritants, which can trigger airway constriction and breathing difficulties.

The odor receptors on the cells might be a therapeutic target, Ben-Shahar suggests. By blocking them, it might be possible to prevent some attacks, allowing people to cut down on the use of steroids or bronchodilators.

When a mammal inhales, volatile chemicals flow over two patches of specialized tissue high up in the nasal passages. These patches are rich in nerve cells with specialized odorant-binding molecules embedded in their membranes.

If a chemical docks on one of these receptors, the neuron fires, sending impulses along the olfactory nerve to the olfactory bulb in the brain, where the signal is integrated with those from hundreds of other similar cells to conjure the scent of old leather or dried lavender.

Aware that airway diseases are characterized by hypersensitivity to volatile stimuli, Ben-Shahar and his colleagues realized that the lungs, like the nose, must have some means of detecting inhaled chemicals.

In 2009, Ben-Shahar found that ciliated cells, cells with tiny hairlike protuberances that are responsible for moving things in the airway, responding to bitterness.

But since people are sensitive to many inhaled substances, not just bitter ones, he wanted to revisit the issue. This time, he found that these tissues also express odor receptors, not on ciliated cells but instead on neuroendocrine cells, flask-shaped cells that dump serotonin and various neuropeptides when they are stimulated.

“When people with airway disease have pathological responses to odors, they’re usually pretty fast and violent,” said Ben-Shahar. “Patients suddenly shut down and can’t breathe, and these cells may explain why.”

Ben-Shahar stresses the differences between chemosensation in the nose and in the lung. The cells in the nose are neurons, he points out, each with a narrowly tuned receptor, and their signals must be woven together in the brain to interpret our odor environment.

Cells in the airways are secretory, not neuronal, cells, and they may carry more than one receptor, so they are broadly tuned. Instead of sending nerve impulses to the brain, they flood local nerves and muscles with serotonin and neuropeptides. “They are possibly designed,” he said, “to elicit a rapid, physiological response if you inhale something that is bad for you.”

The different mechanisms explain why cognition plays a much stronger role in taste and smell than in coughing in response to an irritant. It is possible, for example, to develop a taste for beer. But nobody learns not to cough; the response is rapid and largely automatic.

Scientists suspect these pulmonary neuroscretory cells contribute to the hypersensitivity of patients with COPD to airborne irritants. COPD is a group of diseases, including emphysema, that is characterized by coughing, wheezing, shortness of breath and chest tightness.

When the scientists looked at the airway tissues from patients with COPD, they discovered that they had more of these neurosecretory cells than airway tissues from healthy donors.

Ben-Shahar is hopeful that the PNEC pathways will provide targets for drugs that would better control asthma, COPD and other respiratory diseases. They would be welcome. There has been a steep rise in these diseases in the past few decades, treatment options have been limited, and there are no cures.

The research appears in the March issue of the American Journal of Respiratory Cell and Molecular Biology.

You May Like

Video Genome Initiative Urgently Works to Freeze DNA Before Species Go Extinct

Smithsonian senior research botanist Vicki Funk says ultimate goal is 'trying to get one-half of the diversity of plant life on Earth at the genus level in two years' More

Video Russia Accused of Abusing Interpol to Pursue Opponents

Report from member of British think tank says Russian extradition requests keep targets from traveling More

US Lawmakers Weigh Turkish Anti-terror Moves

Turkey’s two-pronged campaign against Islamic State militants, Kurdish PKK forces provokes mixed reactions on Capitol Hill More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Russia Accused of Abusing Interpol to Pursue Opponentsi
X
Henry Ridgwell
July 28, 2015 9:53 PM
A British pro-democracy group has accused Russia of abusing the global law enforcement agency Interpol by requesting the arrest and extradition of political opponents. A new report by the group notes such requests can mean the accused are unable to travel and are often unable to open bank accounts. VOA's Henry Ridgwell reports.
Video

Video Russia Accused of Abusing Interpol to Pursue Opponents

A British pro-democracy group has accused Russia of abusing the global law enforcement agency Interpol by requesting the arrest and extradition of political opponents. A new report by the group notes such requests can mean the accused are unable to travel and are often unable to open bank accounts. VOA's Henry Ridgwell reports.
Video

Video Genome Initiative Urgently Moves to Freeze DNA Before Species Go Extinct

Earth is in the midst of its sixth mass extinction. The last such event was caused by an asteroid 66 million years ago. It killed off the dinosaurs and practically everything else. So scientists are in a race against time to classify the estimated 11 million species alive today. So far only 2 million are described by science, and researchers are worried many will disappear before they even have a name. VOA’s Rosanne Skirble reports.
Video

Video Scientists: One-Dose Malaria Cure is Possible

Scientists have long been trying to develop an effective protection and cure for malaria - one of the deadliest diseases that affects people in tropical areas, especially children. As the World Health Organization announces plans to begin clinical trials of a promising new vaccine, scientists in South Africa report that they too are at an important threshold. George Putic reports, they are testing a compound that could be a single-dose cure for malaria.
Video

Video Special Olympics Athletes Meet International Friends

The Special Olympics are underway in Los Angeles, California, with athletes from 165 countries participating in an event that gives people with intellectual disabilities the chance to take part in an international competition. VOA's Mike O'Sullivan reports that for athletes and their families, it's also an opportunity to make new friends in an international setting.
Video

Video 'New York' Magazine Features 35 Cosby Accusers

The latest issue of 'New York' magazine features 35 women who say they were drugged and raped by film and television celebrity Bill Cosby. The women are aged from 44 to 80 and come from different walks of life and races. The magazine interviewed each of them separately, but Zlatica Hoke reports their stories are similar.
Video

Video US Calls Fight Against Human Trafficking a Must Win

The United States is promising not to give up its fight against what Secretary of State John Kerry calls the “scourge” of modern slavery. Officials released the country’s annual human trafficking report Monday – a report that’s being met with some criticism. VOA’s National Security correspondent Jeff Seldin has more from the State Department.
Video

Video Iran Nuclear Pact Wins Few New US Congressional Backers

Later this week, President Barack Obama returns from a trip to Africa to confront a U.S. Congress roiled by the nuclear accord with Iran, an agreement that has received the blessing of the U.N. Security Council. Days of intensive lobbying and testimony by top administration officials have won few new congressional supporters of the pact. VOA’s Michael Bowman reports.
Video

Video Washington DC Underground Streetcar Station to Become Arts Venue

Abandoned more than 50 years ago, the underground streetcar station in Washington D.C.’s historic DuPont Circle district is about to be reborn. The plan calls for turning the spacious underground platforms - once meant to be a transportation hub, - into a unique space for art exhibitions, presentations, concerts and even a film set. Roman Mamonov has more from beneath the streets of the U.S. capital. Joy Wagner narrates his report.
Video

Video Europe’s Twin Crises Collide in Greece as Migrant Numbers Soar

Greece has replaced Italy as the main gateway for migrants into Europe, with more than 100,000 arrivals in the first six months of 2015. Many want to move further into Europe and escape Greece’s economic crisis, but they face widespread dangers on the journey overland through the Balkans. VOA's Henry Ridgwell reports.
Video

Video Stink Intensifies as Lebanon’s Trash Crisis Continues

After the closure of a major rubbish dump a week ago, the streets of Beirut are filling up with trash. Having failed to draw up a plan B, politicians are struggling to deal with the problem. John Owens has more for VOA from Beirut.
Video

Video Paris Rolls Out Blueprint to Fight Climate Change

A U.N. climate conference in December aims to produce an ambitious agreement to fight heat-trapping greenhouse gases. But many local governments are not waiting, and have drafted their own climate action plans. That’s the case with Paris — which is getting special attention, since it’s hosting the climate summit. Lisa Bryant takes a look for VOA at the transformation of the French capital into an eco-city.
Video

Video Racially Diverse Spider-Man Takes Center Stage

Whether it’s in a comic book or on the big screen, fans have always known the man behind the Spider-Man mask as Peter Parker. But that is changing, at least in the comic book world. Marvel Comics announced that a character called Miles Morales will replace Peter Parker as Spider-Man in a new comic book series. He is half Latino, half African American, and he is quite popular among comic book fans. Correspondent Elizabeth Lee reports from Los Angeles.
Video

Video Critics of Japan Defense Policy Focus on Okinawa

In Okinawa, many locals have long complained that Tokyo places an unfair burden on the tiny island by locating most of Japan's U.S. military bases there. As Japan's government moves toward strengthening and expanding the country's defense policies, opponents of those plans are joining local protesters in Okinawa, voicing concern about where the country is headed. VOA’s Brian Padden reports from Okinawa.
Video

Video IS Uses Chemical Weapons in Syrian Attack

Islamic State militants have added a new weapon in their arsenal of fear: chemical weapons. VOA Kurdish service reporter Zana Omer was on the scene within hours of a recent attack in Hasakah, Syria, and has details of the subsequent investigation, in this report narrated by Miguel Amaya.
Video

Video Historic Symbol Is Theme of Vibrant New Show

A new exhibit in Washington is paying tribute to the American flag with a wide and eclectic selection of artwork that uses the historic symbol as its central theme. VOA’s Julie Taboh was at the DC Chamber of Commerce for the show’s opening.

VOA Blogs