Can cholesterol help protect against damage done by exposure to alcohol in the womb?

A study of zebrafish suggests that a simple intervention may help to protect unborn children against the damage done by mothers who drink alcohol during pregnancy.

Yin-Xiong Li and colleagues found that exposing zebrafish embryos to low levels of alcohol during very early development blocked the modification of a crucial developmental protein, Sonic Hedgehog (Shh), by cholesterol. The modification of Shh by cholesterol plays a critical role in enabling the protein to guide cell formation and differentiation and embryonic "patterning." Shh is key to the development of the neural tube and early cardiac, gut, and limb structures-all areas affected in fetal alcohol syndrome.

The current study found that alcohol-exposed zebrafish showed defects very similar to those seen in humans exposed to alcohol in utero, including neurological, heart, cranial, and limb malformations. Defects occurred even at very low levels of fetal tissue alcohol concentration, equivalent to those reached if a 120-pound woman ingests a single beer. "This may explain," the researchers say, "why alcohol is the most common teratogen responsible for human congenital defects, and suggests that there is no safe level of alcohol consumption during pregnancy."

The alcohol-exposed zebrafish embryos had reduced cholesterol levels, and when the researchers supplemented the embryos with cholesterol before exposing them to alcohol, Shh performed normally and the fish developed correctly. Thus, the researchers say, cholesterol supplementation appears to correct alcohol-induced Shh defects "at the molecular, cellular, and developmental levels."

Thousands of babies are born each year with neurological damage due to fetal alcohol exposure, which can cause problems ranging from learning and behavioral disabilities to severe retardation. Prenatal exposure to alcohol also is one of the leading risk factors for juvenile delinquency and adult criminality. While only abstinence from alcohol during pregnancy can prevent prenatal alcohol effects, the current study suggests that intervention before birth can reduce the risk of permanent defects. Previous studies (see related articles, Crime Times, 2006, Vol. 12, No. 2, Page 3 and Crime Times, 2001, Vol. 7, No. 2, Page 1 and 5) also indicate that prenatal administration of vitamin B3 or choline can help reduce this risk (see related article, Crime Times, 2007, Vol. 13, No. 2, Page 5).

Related Article: [2007, Vol. 13]