New study on lead exposure paves way for blindness treatment

WASHINGTON - Scientists have discovered some unexpected effects of lead exposure that may one day help prevent and reverse blindness.

Donald A. Fox, a professor of vision sciences in University of Houston College of Optometry described his team’s findings in a paper titled “Low-Level Gestational Lead Exposure Increases Retinal Progenitor Cell Proliferation and Rod Photoreceptor and Bipolar Cell Neurogenesis in Mice.”

The study suggests that lead, or a new drug that acts like lead, could transform human embryonic retinal stem cells into neurons that would be transplanted into patients to treat retinal degenerations.

“We saw a novel change in the cellular composition of the retina in mice exposed to low levels of lead during gestation. The retina contained more cells in the rod vision pathway than normal or than we expected,” said Fox

“The rod photoreceptors and bipolar cells in this pathway are responsible for contrast and light/dark detection. These new findings directly relate to the supernormal retinal electrophysiological changes seen in children, monkeys and rats with low-level gestational lead exposure,” he said.

Fox said these effects occur at blood lead levels at or below 10 micrograms per deciliter, the current low-level of concern by the Centers for Disease Control and Prevention. Because the effects occur below the “safe level,”

The finding was published online in Environmental Health Perspectives. (ANI)