Smoking causes asthma in second generation offspring

The dangers of smoking on smokers and their children are widely known but new research published in BioMed Central's open access journal BMC Medicine demonstrates that nicotine exposure also causes asthma in the smoker's grandchildren.

Asthma is a major public health problem. It is the most common chronic disease of childhood. While there are many factors which contribute to asthma maternal smoking during pregnancy is a well known, and avoidable, risk.

During pregnancy nicotine can affect a developing foetus' lungs, predisposing the infant to . Researchers from Harbor-UCLA Medical Centre, California, tested the effect of during pregnancy on rats, looking not only at their pups (F1) but also at second generation pups (F2).

Exposure inside the uterus resulted in both male and female (F1) offspring having reduced lung function consistent with asthma. It also impaired lung function of their own offspring (F2), even though the F1 rats were not themselves exposed to nicotine once they were born. Levels of proteins increased by maternal smoking in the lungs of their offspring such as fibronectin, collagen and nicotinic aceylcholine receptors, were also found to be raised in the grandchildren. Similarly the expression of PPARγ, a normal , was reduced in first and second generation offspring.

Dr Virender Rehan, who led this study commented, "When we looked at the effect of nicotine on DNA in the testes or ovaries of the rats they found that nicotine increased the level of methylation in the testes but reduced it in the ovaries. Nicotine also altered methylation of histones in a sex-dependent manner. These epigenetic marks may be the mechanism behind how nicotine-induced asthma is transmitted from one generation to the next."

Treating the mothers with a synthetic version of PPARγ, known to normalise lung function in nictotine exposed offspring also prevented to F2 offspring and restored normal histone modification patterns in their lungs.

The effects of smoking during pregnancy are, it seems, very long lasting. Stop smoking education and intervention aimed at mothers-to-be and women planning pregnancy needs to take into account the fact that nicotine itself contains dangers to their children and their children's children.

add to favorites email to friend print save as pdf

Related Stories

Helping ex-smokers resist the urge

Oct 22, 2012

A new inhibitor helps previously nicotine-addicted rats stay on the wagon, according to a study published on October 22nd in the Journal of Experimental Medicine.

Recommended for you

Suddenly health insurance is not for sale

Apr 18, 2014

(HealthDay)— Darlene Tucker, an independent insurance broker in Scotts Hill, Tenn., says health insurers in her area aren't selling policies year-round anymore.

Study: Half of jailed NYC youths have brain injury (Update)

Apr 18, 2014

About half of all 16- to 18-year-olds coming into New York City's jails say they had a traumatic brain injury before being incarcerated, most caused by assaults, according to a new study that's the latest in a growing body ...

Autonomy and relationships among 'good life' goals

Apr 18, 2014

Young adults with Down syndrome have a strong desire to be self-sufficient by living independently and having a job, according to a study into the meaning of wellbeing among young people affected by the disorder.

User comments

Adjust slider to filter visible comments by rank

Display comments: newest first

tadchem
not rated yet Oct 30, 2012
They cannot even tell us with any certainty what causes asthma.