New Congo red test predicts development of preeclampsia with pregnant women
What is preeclampsia?
Preeclampsia is serious pregnancy complication, characterized by an increase in blood pressure and an increase in the protein content of the mother’s urine. Preeclampsia occurs in ~2-8% of pregnancies, and if untreated can lead to eclampsia, resulting in seizures, liver damage, stroke, blindness, and coma. It is a worldwide leading cause of maternal and perinatal morbidity and mortality (that’s doctor speak for disease and death). Unfortunately, the only known cure for preeclampsia is delivery of the baby and placenta. Even more unfortunately, preeclampsia is very difficult to diagnose when the mother has a preexisting condition with similar symptoms.
A large collaboration of scientists recently reported a new method of determining which women would develop preeclampsia. Urine samples were collected from more than 600 patients and mixed with a dye called Congo red. Congo red stains large clumps of proteins, but doesn’t mark smaller separate proteins. It is important to know that proteins don’t usually stick together – this aggregation is a result of protein misfolding. Protein aggregation is common in disorders like Alzheimer’s, Parkinson’s, and mad cow disease. Researchers found that urine from women with preeclampsia had increased red staining of proteins. They also found that women who went on to develop preeclampsia had increased red staining before a clinical diagnosis was made. In addition, the Congo red test predicted development of preeclampsia in women with preexisting conditions. When the scientists looked at which proteins were aggregating, they found that several proteins were consistently present. One of these was amyloid precursor protein, which is well known to be involved in the pathogenesis of Alzheimer’s disease.
What’s the good news?
This new test is fairly simple to perform, which means it can hopefully be used in developing countries, which have the highest preeclampsia mortality rates. Because the Congo red test gives results before the appearance of clinical symptoms, treatment decisions can be made before a medical emergency occurs. The finding of protein misfolding also opens up possibilities for testing the efficacy of existing Alzheimer’s drugs on preeclampsia.
Photo: Flickr, Emery Co Photo
Buhimschi IA, Nayeri UA, Zhao G, Shook LL, Pensalfini A, Funai EF, Bernstein IM, Glabe CG, & Buhimschi CS (2014). Protein misfolding, congophilia, oligomerization, and defective amyloid processing in preeclampsia. Science translational medicine, 6 (245) PMID: 25031267
Whitehead, N. (2014). Proteins and a pregnancy woe Science, 345 (6194), 249-249 DOI: 10.1126/science.345.6194.249
preeclampsia, pregnancy, congo red, protein folding, delivery, eclampsia, health