Intrauterine growth retardation (IUGR) refers to poor growth of a fetus while in the mother’s womb during pregnancy. Technically, IUGR babies are those babies that weigh less than 51/2 pounds or 2.5 kgs at the time of delivery.
This condition makes the babies susceptible to a wide range of serious health problems. Physicians have not yet proven what causes intrauterine growth restriction, but most blame a malfunction in the placenta that prevents the mother’s bloodstream from delivering oxygen and nutrients to her fetus, thereby causing sub-optimal growth.
UCLA scientists have recently discovered higher levels of a protein called humanin in the placenta tissue of women who gave birth to severely underweight infants.
Humanin plays a role in breaking down carbohydrates and delivering nutrients to organs and muscle. The researchers suspect that levels of humanin rise to protect the fetus when the placenta fails, which is a common cause of babies being born at below-normal weights.
While studying the human placenta, the UCLA researchers looked at gene expression, the process by which a gene’s DNA sequence is converted into cellular proteins. They compared the placentas of women who gave birth to healthy babies to the placentas of women who delivered low-birthweight infants.
The team found significantly higher levels of humanin in the latter group. This protein protects against oxidative stress, which hampers the body’s ability to defend itself against toxic free radicals, a type of particle linked to disease.
Significance of the study
The finding may help researchers unravel the reasons that low-birthweight babies face a higher risk of obesity, high blood pressure, diabetes and heart disease as adults.
The findings are published in the March 28 edition of PLOS ONE.
Source: UCLA Newsroom