Research

New type of tissue found in the eye

Researchers have found cellular components in the epithelial tissue of the eye that were previously only thought to be present in electrically active tissues. It is hoped the discovery could lead to new treatments for diseases that are currently incurable.

A team from Tampere University, Finland, identified voltage-gated sodium (Nav) channels present in the eye’s epithelial tissue, and found that they play a role in the renewal of the retina’s sensory cells. Previously, this particular cellular component was only believed to be in electrically active tissues such as the heart or nerves.

“The research project focused on the retinal pigment epithelium (RPE), a tissue that is critically important to the functioning of the retina,” Dr Soile Nymark, Academy of Finland research fellow, said.

“The project revealed proteins in the RPE whose function is essential for neural tissue, but whose prevalence or activity in epithelial tissue has not been previously reported. These proteins, voltage-gated sodium channels, are typically responsible for generating electrical signals in the nerve cells.”

The discovery reveals how the ion channel proteins responsible for the electrical signalling of neurons influence the phagocytosis process. Since this process is disrupted in many retinal degenerative diseases, such as age-related macular degeneration, it is hoped this new knowledge could lead to a greater understanding of diseases and, subsequently, new treatments.

The researchers made the discovery by applying techniques to eye calls that have traditionally been used to understand the electrical communications of nerve cells.

“This perspective enabled our new observation and highlights that the major role of electrical phenomena and the underlying ion channels in the functioning of epithelial tissue may not yet be fully understood,” Nymark said.

Future studies will focus on the specific role of these ion channels. The findings were published in the journal BMC Biology.