Maternal diabetes alters extracellular matrix protein levels in rat placentas.

OBJECTIVES The aim of this study was to determine whether maternal diabetes affects placental levels of the extracellular matrix components fibronectin, laminin, and collagen-IV. STUDY DESIGN Fibronectin, laminin, and collagen-IV deposition in term (day 20) rat placentas from normal and diabetic pregnancies was detected by use of Western blot, slot-blot, and immunohistochemical studies. RESULTS Increased placental and decreased fetal wet weight were found in offspring of manifestly diabetic rats compared with offspring of normal pregnancies. Laminin deposition was reduced whereas fibronectin levels were increased in placentas from diabetic rats. No diabetes-induced changes of collagen-IV expression and deposition were found. CONCLUSION The diabetes-induced alterations of laminin and fibronectin protein levels in the fetal-maternal interface may affect placental development and alter gas exchange and nutrient transfer to the offspring. This may in turn contribute to the abnormal fetal development in diabetic pregnancy.