Study reveals lung changes in mice exposed to second-hand smoke in utero

June 26, 2017
Credit: Vera Kratochvil/public domain

Mice exposed to second-hand smoke only during gestation undergo abnormal changes to lung structure and function that persist into adulthood, according to research published in the open access journal Respiratory Research. The study provides new insight into the role second-hand smoke exposure may play in predisposing unborn offspring to adult lung diseases.

Male and female mice exposed to second-hand smoke during gestation were found to have altered lung structure that was indicative of tissue damage. In addition, tests on those offspring after they reached adulthood revealed that tidal volume (the amount of air inhaled and exhaled per breath during normal breathing) and minute volume (the volume of air inhaled or exhaled per minute during normal breathing) were significantly decreased in male mice that had been exposed to second hand smoke, but not in . Molecular analysis of revealed that several genes were impacted by second hand smoke exposure, including a gene in humans, called A1AT, which is a known genetic risk factor for emphysema.

Professor Arthur Penn, senior author from Louisiana State University, said: "Our study strongly indicates that in utero second hand smoke exposure alone has significant persistent repercussions on the respiratory system, suggesting that in utero second-hand smoke exposure can predispose to adult in mice."

Dr Alexandra Noël, lead author and Assistant Professor at Louisiana State University School of Veterinary Medicine, said: "The more pronounced lung function changes in male versus female offspring are consistent with results of other studies showing that lung development of male fetuses lags behind that of females".

In the US, over 126 million people each year, including pregnant women, are exposed to second-hand smoke. While it is known that offspring of mothers who smoked while pregnant exhibit altered lung function and increased susceptibility to respiratory diseases, not much is known about the effects of direct exposure to second-hand smoke on fetal lungs.

Pregnant mice were exposed to second-hand smoke mixed with filtered air in order to isolate the mice from any other potential airborne exposures that could affect the developing fetus. Mice from the litters were then allowed to develop to adulthood isolated from exposures other than filtered air and separated by sex and the type of in utero exposure to create four test groups. Lung function measurements, examination of lung tissue for signs of damage, and molecular analysis of tissue were all performed once the mice had reached adulthood at 15 weeks of age.

This study is limited by the fact that it was carried out in , so it is difficult to extrapolate the findings directly to humans. The results however, provide a possible explanation for the association between second-hand smoke exposure in pregnant women and elevated risk of respiratory diseases in their offspring. Another limitation is that levels of exposure used in this experiment may not be directly comparable to exposure levels encountered by human fetuses.

Explore further: Animal study shows harmful effects of secondhand smoke even before pregnancy

More information: Alexandra Noël et al, Sex-specific lung functional changes in adult mice exposed only to second-hand smoke in utero, Respiratory Research (2017). DOI: 10.1186/s12931-017-0591-0

Related Stories

Animal study shows harmful effects of secondhand smoke even before pregnancy

January 5, 2017
Exposure to second-hand tobacco smoke—even before conception—appears to have a lingering impact that can later impair the brain development of a fetus, researchers at Duke Health report.

Unknown exposure to second-hand smoke associated with increased mortality

September 26, 2016
A new biomarker has identified known and unknown exposure to second-hand smoke and confirmed a strong association to increased mortality in non-smokers, according to a new study from the Icahn School of Medicine at Mount ...

Maternal smoking disrupts retinoid pathways in the developing fetal lung

May 31, 2012
Maternal smoking can lead to lung disease in babies, including asthma. New research published in BioMed Central's open access journal Respiratory Research shows that maternal smoking-related defects within the alveoli inside ...

New study compares the effects of direct exposure to cigarette smoke or e-cigarette vapor

February 6, 2017
Researchers reported changes in the expression levels of 123 genes when reconstituted lung tissue was exposed to cigarette smoke, compared to only two genes that could be confirmed following exposure to e-cigarette aerosols. ...

Nicotine exposure during and after pregnancy can cause hearing problems in children

February 13, 2017
Nicotine exposure, before and after birth, can cause a child to have hearing problems due to abnormal development in the auditory brainstem. This is according to a mouse model study published in The Journal of Physiology.

Occasional marijuana use doesn't harm lungs, study finds

January 12, 2012
Smoking marijuana on an occasional basis does not appear to significantly damage the lungs, according to a new study.

Recommended for you

Eating better throughout adult years improves physical fitness in old age, suggests study

October 18, 2017
People who have a healthier diet throughout their adult lives are more likely to be stronger and fitter in older age than those who don't, according to a new study led by the University of Southampton.

Across Asia, liver cancer is linked to herbal remedies: study

October 18, 2017
Researchers have uncovered widespread evidence of a link between traditional Chinese herbal remedies and liver cancer across Asia, a study said Wednesday.

Global calcium consumption appears low, especially in Asia

October 18, 2017
Daily calcium intake among adults appears to vary quite widely around the world in distinct regional patterns, according to a new systematic review of research data ahead of World Osteoporosis Day on Friday, Oct. 20.

New study: Nearly half of US medical care comes from emergency rooms

October 17, 2017
Nearly half of all US medical care is delivered by emergency departments, according to a new study by researchers at the University of Maryland School of Medicine (UMSOM). And in recent years, the percentage of care delivered ...

Experts devise plan to slash unnecessary medical testing

October 17, 2017
Researchers at top hospitals in the U.S. and Canada have developed an ambitious plan to eliminate unnecessary medical testing, with the goal of reducing medical bills while improving patient outcomes, safety and satisfaction.

No evidence that widely marketed technique to treat leaky bladder/prolapse works

October 16, 2017
There is no scientific evidence that a workout widely marketed to manage the symptoms of a leaky bladder and/or womb prolapse actually works, conclude experts in an editorial published online in the British Journal of Sports ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.