NOV 01, 2017 10:29 AM PDT

Smoking May Be Giving You Inflammatory Bowel Disease

WRITTEN BY: Kara Marker

Smoking cigarettes is a habit well-known for its association with an increased risk for lung cancer, heart disease, and countless other conditions. Today, you can add one more to the list: inflammatory bowel disease. It may seem farfetched that disease in the lungs can lead to disease in the gut, but a new study from scientists at South Korea’s Kyung Hee University shows that these two regions are more connected than you might realize.

The CDC estimates that 36.5 million adults in the United States smoke cigarettes.

Previous findings have shown that smoking increases a person’s risk of Crohn’s disease, a type of inflammatory bowel disease, but the present study is the first to confirm a direct causative relationship between smoking and intestinal inflammation.

“Crohn's disease is more likely to occur in people with airway diseases, suggesting that inflammation in the lungs is linked with inflammation in the gut,” explained study researcher Hyunsu Bae.

Researchers began their study by exposing groups of mice to cigarette smoke, comparing any observations they made with a control group that was not exposed to smoke. As expected, mice exposed to smoke developed inflammation in the lungs. However, researchers also saw evidence of inflammation in the colon, along with blood in the feces and abnormally high levels of an immune cell called CD4+ T cells, which were also producing the pro-inflammatory protein interferon-gamma.

With the relationship between smoking and intestinal inflammation narrowed down to the involvement of CD4+ T cells and interferon gamma, researchers then asked: How do the effects from smoking reach the gut all the way from the lungs?

They repeated the same experiment except with one group of mice with few CD4+ T cells and one group that was unable to produce interferon-gamma. Neither group developed gut inflammation after smoke exposure, confirming the role of CD4+ T cells in causing gut inflammation after smoking.

Researchers performed one last experiment, again exposing mice to smoke. This time, though, they took from the lungs of the mice their population of CD4+ T cells and injected them into a different group of mice that had never been exposed to smoke. However, these mice developed colitis anyway, confirming that CD4+ T cells are directly responsible for colitis from cigarette smoking.

"Our results suggest that cigarette smoking activates specific white blood cells in the lung, which might later move to the colon, triggering bowel inflammation," explained study researcher Jinju Kim. "Smokers, especially those who also have bowel disease, should reduce their smoking."

Bae, Kim, and others are hoping that elucidating the direct relationship between smoking and inflammatory bowel disease could lead to new treatments and increased awareness among smokers concerning their risk of developing the disease.

 

The present study was published in the journal Frontiers in Immunology.

 

Source: Frontiers

About the Author
  • I am a scientific journalist and enthusiast, especially in the realm of biomedicine. I am passionate about conveying the truth in scientific phenomena and subsequently improving health and public awareness. Sometimes scientific research needs a translator to effectively communicate the scientific jargon present in significant findings. I plan to be that translating communicator, and I hope to decrease the spread of misrepresented scientific phenomena! Check out my science blog: ScienceKara.com.
You May Also Like
AUG 04, 2019
Immunology
AUG 04, 2019
New Research In Reversing Deafness
Hair cells inside the human ear are responsible for sensing and relaying sound to the brain.  In all mammals except humans, these cells can regenerate...
OCT 29, 2019
Immunology
OCT 29, 2019
Immune Protein Prevents Herpes Spreading to the Brain
An immune protein that was discovered more than two decades ago has been identified as the primary component of a molecular blockade that prevents genital ...
DEC 21, 2019
Drug Discovery & Development
DEC 21, 2019
Improving Vaccines for Meningitis
Scientists at the University of Nottingham are seeking new ways to improve vaccine use in the protection against the bacterium, Neisseria meningitides that...
JAN 07, 2020
Immunology
JAN 07, 2020
"Good" T Cells Can Go "Bad," But in the Case of Cancer, That's A Good Thing
T cells may be able to reach their full potential in the fight against cancer with a little nudge. In 2010, scientists first observed CD4+ T cells transiti...
JAN 08, 2020
Cell & Molecular Biology
JAN 08, 2020
In a First, Scientists Generate Early Human Immune Cells in the Lab
Now we know more about the early stages of the human immune system....
FEB 10, 2020
Immunology
FEB 10, 2020
How Cancer Evades the Immune System Time and Time Again
Scientists discovered a new mechanism by which cancer cells evade the immune system to further their own agenda: invade, multiply, and spread. Identifying...
Loading Comments...