U.S. scientists discover cause of fetal hydrocephalus U.S. scientists report that their experiments with mice found that fetal hydrocephalus may be caused by an excess of a substance called lysophosphatidic acid. This finding may help in the diagnosis and treatment of fetal hydrocephalus. Fetal hydrocephalus is a neural tube malformation caused by excessive accumulation of cerebrospinal fluid in the ventricular system, which can lead to brain damage, abnormally large heads and possible death in newborns. Current treatment is mainly through surgical implantation of a shunt device to help the fluid drain, but the long-term results are not satisfactory. Hydrocephalus has previously been found to be associated with intracranial hemorrhage, but it is not clear exactly how. Scientists at the Scripps Research Institute found that lysophosphatidic acid ( LPA), a normal component of the blood, may be the key to the problem. Experiments have found that injecting lysophosphatidic acid into the ventricles of mouse embryos can trigger signs similar to hydrocephalus in human fetuses; however, if a compound is injected beforehand that prevents lysophosphatidic acid from binding to receptor molecules on the surface of brain cells, then injecting lysophosphatidic acid does not trigger hydrocephalus. This is akin to overdosing,” the researchers said. Lysophosphatidic acid is a normal component of serum, secreted by platelets, fibroblasts, and adipocytes, and is a signaling molecule with a variety of biological functions that play an important role in neuronal and other cell development. If there is an excess of lysophosphatidic acid, the activity of receptor molecules on the surface of brain cells becomes abnormal, leading to structural changes in the fetal brain during formation and abnormal changes in the location of some cells, including those that help control fluid flow, eventually leading to hydrocephalus. Guoqiang Xie, Department of Neurosurgery, Xianyang 215 Hospital