Scientific Update: Placental Genetic Material in Maternal Blood Could Potentially Diagnose Gestational Diabetes Early, Says Small NIH-Funded Study | NICHD
A new method to detect genetic material from the placenta in the blood of pregnant women could potentially identify the risk of gestational or pregnancy-related diabetes in the first trimester, suggests a small study funded by the National Institutes of Health. Typically, gestational diabetes isn’t diagnosed until late in the second or third trimester. The method could be used to identify patients who would benefit from preventive treatments before diabetes develops.
The new method isolates extracellular vesicles (EVs) secreted by the placenta from the blood. EVs are membrane-bound sacs containing microRNAs, the molecular scaffold on which proteins are assembled. The EVM microRNAs of women who later develop gestational diabetes differ from those of other pregnant and non-pregnant women.
The study was led by Sherin U. Devaskar, MD, and colleagues at the David Geffen School of Medicine at the University of California, Los Angeles. He appears in PLOS ONE.
Gestational diabetes refers to high blood sugar (glucose) levels during pregnancy. The condition can be treated, but it is associated with a higher risk of maternal high blood pressure and increased body fat in newborns. The larger fetal size often seen in gestational diabetes can lead to labor problems, including a higher risk of cesarean delivery. Later in life, children born to women with gestational diabetes are at higher risk of obesity. Gestational diabetes also increases maternal risk for obesity, type 2 diabetes and cardiovascular disease later in life. A method to identify people at risk for gestational diabetes in the first trimester could allow doctors to provide early interventions to reduce the severity of the condition or prevent it from occurring.
EVs containing microRNAs and other genetic material are released by cells, including placental cells. From six weeks of pregnancy, the placenta begins to release electrical vehicles into the maternal circulation. The amount of EVs increases throughout pregnancy, peaks in the third trimester, and decreases after delivery.
For the current study, researchers compared EV microRNAs from three healthy non-pregnant women, seven people with healthy pregnancies, and 14 with gestational diabetes.
The blood EVs of the pregnant participants contained 296 microRNAs that were not present in the circulation of the non-pregnant participants. Of the 296 microRNAs, 269 were more abundant in participants later diagnosed with gestational diabetes. For the second trimester, 130 microRNAs were present only in people diagnosed with gestational diabetes, and 45 found only in those who did not develop the disease. For the third trimester, 112 microRNAs were found only in participants with gestational diabetes and 28 only in those without gestational diabetes. At delivery, people with gestational diabetes and without the disease had 19 microRNAs, 10 of which were more prevalent in people with gestational diabetes. Another microRNA was only found in participants without gestational diabetes.
The authors concluded that analyzing EVs for the microRNAs they contain has the potential to identify gestational diabetes in early pregnancy.
“This study provides more evidence that gestational diabetes is a condition that begins to develop much earlier than when it is currently clinically diagnosed,” Dr. Devaskar said. “We are excited about this step towards the potential for more reliable and earlier diagnosis so that we can intervene before the development of adverse conditions for mother and baby that often last a lifetime.”
Thamotaran, S et al. Circulating extracellular vesicles exhibit a differential miRNA profile in gestational diabetic pregnancies. PLOS ONE. 2022. https://doi.org/10.1371/journal.pone.0267564