Unraveling the mechanism of skin barrier formation

April 14, 2017

Scientists have identified the gene responsible for generating acylceramide, the key lipid in forming the skin barrier that protects us from pathogens, allergens and other harmful substances. This finding could prove crucial in developing medicines for treating atopic dermatitis and ichthyosis.

Defects of the can trigger skin diseases such as atopic dermatitis, which is said to afflict about 10 percent of the population in some developed countries. Acylceramide, a lipid only found in skin, plays a pivotal role in forming this barrier. Although most of the genes needed to generate this special lipid have been recently identified, the gene responsible in the final step to produce acylceramide has been missing. Finding the last piece in the puzzle, therefore, was essential for elucidating the skin barrier's molecular mechanism.

The team led by Professor Akio Kihara at Hokkaido University established a cell system that produces the acylceramide precursor ω-hydroxyceramide and used it to evaluate the activity of several candidate genes to produce acylceramide. The research methodology addressed a long-standing hurdle in experiments using epidermal keratinocytes which caused the inefficiency of gene delivery to the cells. By using other type of cultured cells transfected with the required for other steps of acylceramide synthesis, the team has overcome the issue and tested the function of the .

As a result, the team succeeded in finally identifying the key gene as PNPLA1. The researchers also found evidence that suggests the lipid triglyceride acts as a linoleic acid donor. Furthermore, they discovered that mutant PNPLA1 proteins found in patients with ichthyosis, a serious genetic skin disorder characterized by dry and scaly skin, show reduced or no enzyme activity.

As there is no curative treatment for , patients are currently given only symptomatic therapies. No treatment has been established for ichthyosis. "To better treat such patients, it is essential to restore the functions of the skin barrier," says Akio Kihara. "Having unraveled the of acylceramide synthesis, our study should enable the search for compounds that boost acylceramide synthesis and therefore restore the skin barrier."

This study was conducted as a part of a project under the Advanced Research and Development Programs for Medical Innovation (AMED-CREST) of the Japan Agency for Medical Research and Development.

Explore further: Discovery of a new metabolic pathway of a known lipid has implications in cancer, obesity

More information: Yusuke Ohno et al. PNPLA1 is a transacylase essential for the generation of the skin barrier lipid ω-O-acylceramide, Nature Communications (2017). DOI: 10.1038/NCOMMS14610

Related Stories

Recommended for you

'CYCLOPS' algorithm spots daily rhythms in cells

April 25, 2017

Humans, like virtually all other complex organisms on Earth, have adapted to their planet's 24-hour cycle of sunlight and darkness. That circadian rhythm is reflected in human behavior, of course, but also in the molecular ...

Discovery offers new hope to repair spinal cord injuries

April 24, 2017

Scientists at the Gladstone Institutes created a special type of neuron from human stem cells that could potentially repair spinal cord injuries. These cells, called V2a interneurons, transmit signals in the spinal cord to ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.