According to research from Western University in London, Canada, pregnant women who expose their fetuses to nicotine, either by way of smoking or nicotine replacement therapy (NRT), increase the likeliness of long-term adverse reactions for their children. These reactions include an increased risk of obesity and metabolic syndrome by influencing the liver to produce more triglyceride.
The research, led by Daniel Hardy, PhD, of the Schulich School of Medicine and Dentistry, is published online in the journal Toxicology and Applied Pharmacology.
“We knew smoking was bad during pregnancy. But the problem is that one-fifth of pregnant women in Canada continue to smoke, and 30 prospective studies have shown us that that babies born to smoking mothers have a 47 percent increase in the odds of becoming overweight – that’s even after adjusting for the mom’s diet and socioeconomic status,” says Hardy. “Our studies were designed to find if there is a biological basis between nicotine exposure from either NRT or smoking, and obesity and metabolic syndrome later in the offspring’s life.”
Working in collaboration with Alison Holloway, PhD, of McMaster University, Hardy gave pregnant laboratory rats the same amount of nicotine, adjusted for weight, that an average smoker receives (1 mg per kg a day). The exposed rats were born smaller in size, but once they reached adulthood, they developed an increase in liver and circulating triglycerides, a hallmark of obesity.
The study also demonstrated that the nicotine-exposed liver, long-term, makes more triglycerides via transcriptional and epigenetic changes.
Hardy notes that through continued research, his team will work to see if increased perinatal doses of folic acid will prevent or reverse the nicotine damage to the developing liver. According to Hardy, folic acid has been shown to reduce circulating triglycerides in animal studies, and smoking moms have been found to have low levels of folate.