Children born to women with late-stage gestational diabetes — caused by a pregnancy-related, transient increase in blood sugar levels (hyperglycemia) — or to women who are overweight or obese are known to be a higher risk of pulmonary complications, namely respiratory distress and persistent pulmonary hypertension of the newborn (PPHN). While efforts to treat diabetes during pregnancy are well-established, a new study suggests that circulating lipids generated by a mother’s high-fat diet are also important in creating this risk in an infant.
To better understand the possible association between obesity, diabetes, and PPHN, a research team at the University of South Dakota studied pregnant rats with gestational diabetes being fed a high-fat diet. They found that these rats gave birth to offspring with pulmonary complications, which lasted the three weeks they were alive. The data were published in the journal PloS One, in a study titled, “Consequences of a Maternal High-Fat Diet and Late Gestation Diabetes on the Developing Rat Lung.”
“To date, there are very few studies investigating the effects of maternal HF diet on pulmonary development, and to our knowledge, no other study has looked at the combined effect or followed offspring past the perinatal time-point,” the team wrote.
Researchers gave female rats a high-fat diet four weeks prior to mating. When the animals became pregnant, and eight days before delivery, the team induced diabetes in the animals. Because researchers wanted to exclude postnatal influence from diabetic or high-fat mothers, the pups were fed by normal foster mothers.
The team found that pregnant rats under a high-fat diet had an offspring mortality rate 89% higher than pregnant rats with diabetes or those given a healthier, control diet. Importantly, researchers found that high-fat diet combined with gestational diabetes affected lung maturity and lung function in the surviving three-week-old offspring. The combination reduced the lung’s ability to stretch and expand, known as lung compliance, in the young rats.
Based on lung vessel and alveolar morphological studies, the team proposed that impaired maturation and vascularization of the lung is probably multifactorial. Glucose, insulin, fatty acids, and inflammatory factors together seem to contribute to lung abnormalities.
The authors concluded that the study may offer new therapeutic strategies to decrease lung complications in babies born to obese and diabetic mothers.
“Knowledge gained provides a foundation for the investigation of preventative and therapeutic strategies aimed at decreasing pulmonary morbidity in at-risk infants. A desperate area in need of ongoing research is to continue to understand how a maternal HF [high-fat] diet could exacerbate the effects of diabetic pregnancy,” the authors wrote.