Advanced Search
Current and Breaking News for Professionals, Consumers and Media



Click here to learn how to advertise on this site and for ad rates.

Obesity Issues Author: Staff Editor Last Updated: Dec 15, 2013 - 2:04:03 PM



Obesity May Cause Asthma by Altering the Immune System

By Staff Editor
Dec 15, 2013 - 2:00:03 PM



Email Newsletter icon, E-mail Newsletter icon, Email List icon, E-mail List icon Sign up for our Ezine
For Email Marketing you can trust


Email this article
 Printer friendly page

(HealthNewsDigest.com) - BOSTON, Dec. 15, 2013  -- Research conducted at Boston Children's Hospital indicates that obesity might cause asthma via factors in the immune system and suggests a new way of treating asthma in obese people--who often respond poorly to standard asthma medications. The study, conducted in a mouse model of asthma and in human lung fluid, was published online Dec. 15 by Nature Medicine.

A growing body of literature links asthma with obesity, but the reason for the link has been unknown. Both conditions have become more common over the last several decades. The new study, led by Dale Umetsu, MD, PhD, and Hye Young Kim, PhD, of the Division of Allergy and Immunology at Boston Children's, explored obesity's effects on the immune system.

"Since it's been a puzzle to understand why obesity predisposes people to asthma, our goal was to find the connection between these two problems, which occur in both children and adults and to explore possible new treatments," says Umetsu.

The researchers studied mice that were fed a high-fat diet causing them to become obese. Unlike mice fed normal diets, the obese mice developed airway hyper-reactivity or constricted and twitchy airways, the predominant feature of asthma.

In the study, obesity appeared to alter the innate immune system--the body's first responder to infection--in several ways to cause lung inflammation. The lungs of the obese, asthmatic mice had several differences from those of non-obese mice:


--  High levels of the protein interleukin 17A (IL17A), a cytokine
(signaling molecule) associated with several inflammatory conditions
--  Increased numbers of the immune cells that produce IL17A, known as type3
innate lymphoid cells (ILC3 cells)
--  Activation of an inflammatory protein known as NLRP3 inside lung cells
--  Increased production of the cytokine IL-1 , a stimulator of ILC3 cells.
When the obese mice were genetically altered in that they could not produce IL17A or NLRP3, they did not develop asthma. But when the same mice had IL-1  or ILC3 cells placed directly in their lungs, either was enough to spur production of IL7A and to cause asthma symptoms.

"We have discovered an inflammatory pathway to asthma that previously had not been recognized," says Umetsu "This pathway may be resistant to standard asthma medications such as corticosteroids."

In addition, when IL-1  production was blocked with the drug anakinra (Kineret, Swedish Orphan Biovitrum), used to treat rheumatoid arthritis, the obese mice did not develop asthma.

Although the researchers were unable to study human patients directly, they did examine lung fluid from 10 patients with lung disease who underwent bronchoalveolar lavage, a diagnostic test. Those with severe asthma had increased numbers of ILC3 cells producing IL-17 as compared with those with mild asthma or no asthma--circumstantial evidence suggesting that the mouse model may mirror what occurs in obese people who develop asthma.

"Obese people have been noted to have elevated systemic levels of IL-17 and IL-1 , particularly those who have non-allergic asthma," notes Umetsu.

The National Institutes of Health and the D. and D. Bunning Food Allergy Project funded the study.

Note:After the study concluded, Umetsu accepted the position of principal medical director at Genentech, where he now works. He is no longer affiliated with Boston Children's Hospital.

Boston Children's Hospital is home to the world's largest research enterprise based at a pediatric medical center, where its discoveries have benefited both children and adults since 1869. More than 1,100 scientists, including seven members of the National Academy of Sciences, 13 members of the Institute of Medicine and 14 members of the Howard Hughes Medical Institute comprise Boston Children's research community. Founded as a 20-bed hospital for children, Boston Children's today is a 395-bed comprehensive center for pediatric and adolescent health care grounded in the values of excellence in patient care and sensitivity to the complex needs and diversity of children and families. Boston Children's is also the primary pediatric teaching affiliate of Harvard Medical School. For more information about research and clinical innovation at Boston Children's, visit: http://vectorblog.org.

Web Site: http://www.childrenshospital.org/

###
For advertising and promotion on HealthNewsDigest.com, call Mike McCurdy: 877-634-9180 or tvmike13@HealthNewsDigest.com[email protected] We have over 7,000 journalists as subscribers.



Top of Page

HealthNewsDigest.com

Obesity Issues
Latest Headlines


+ Obesity Prevention Programs Can Lower Kids’ Blood Pressure
+ Life Expectancy Gains Elude Overweight Teens
+ Obesity Declared a Disease. So, What Happens Next?
+ Do Obesity, Birth Control Pills Raise Risk of Multiple Sclerosis?
+ Obese Patients Who Feel Judged By Doctors Are Less LIkely to Shed Pounds
+ Kindergarten Weight Strong Indicator of Childhood Obesity
+ Labeling Obesity as a Disease May Have Psychological Costs
+ Neuroscience Study Uncovers New Player in Obesity
+ Obese Children Have Higher Stress Hormone Levels than Normal Weight Peers
+ Obesity May Cause Asthma by Altering the Immune System



Contact Us | Job Listings | Help | Site Map | About Us
Advertising Information | HND Press Release | Submit Information | Disclaimer

Site hosted by Sanchez Productions