Japanese researchers describe molecular pathway that influences nighttime IOP rise

A new study published in Communications Biology has explored how a molecular pathway contributes to nighttime intraocular pressure (IOP) rises.

The researchers illustrated how the neurotransmitter norepinephrine increases levels of the RHOB molecule, which weakens the eye’s ‘cleaning function’ and results in an increase in IOP.

Keisuke Ikegami, an associate professor from Kyushu University’s faculty of agriculture, explained that previous research has found that signals from the sympathetic nervous system contribute to the nighttime rise in IOP. However, there was limited understanding of the underlying process.

“We decided to investigate how norepinephrine can change the function of fluid drainage in the eye and whether it can explain why eye pressure increases at night,” he said.

The researchers found that norepinephrine increased RHOB in trabecular meshwork cells. When RHOB was removed from human cells, the ability of the cells to take up and clear particles increased.

When RHOB was added, cleaning activity and fluid movement in the eye reduced.

The scientists highlighted that the RHOB pathway is a key regulator of IOP rhythm and a potential target for glaucoma treatment.

“We hope our work will lead to new treatment regimens and strategies for administering medicines to achieve the greatest effect,” Ikegami said.