Autophagy and ageing: Kao’s new research reveals decline of body’s ‘recycling’ process

Autophagy is a process which allows the body to clear out damage cells in order to generate new, healthy cells. This process essentially recycles contents in the body to create new proteins.

According to Kao, the human body is in a constant state of self-renewal, with a recycling rate of 1% to 2% of total proteins.

Previous research has determined that its activity decreases with ageing it is also thought to be involved in various age-related diseases. In skin, autophagy is known to have some important roles, such as keratinisation, immunity and pigmentation.

Under the guidance of Professor Tamotsu Yoshimori from Osaka University, Kao’s Biological Science Research Division successfully measured autophagy activity and found a link between its decrease and the ageing process.

To examine the connection between skin ageing and autophagy, researchers collected skin tissues from six healthy female volunteers in their 40s and 50s.

Skin tissues were collected from a ‘sun-protected’ area on the upper inner arm and the scientists determined autophagy activity in skin by detecting changes in LC3 or p62 proteins.

In another study, the team examined pigment spots on the outer forearm, an area that is frequently exposed to the sun, and compared it with the skin on the upper inner arm.

The results showed that autophagy activity was significantly lower on the skin with pigmentation spots caused by UV damage. This suggested that autophagy decline was a consequence of photoaging.

Based on these findings, Kao’s researchers concluded that restoration of autophagy can contribute to the improvement of skin damaged by ageing and sun exposure by normalising protein homeostasis.

Looking for potentials in autophagy

These findings were first presented at the 29^th​ annual meeting of the Japanese Society for Pigment Research in Okayama, Japan.

This research is a continuation of Kao’s previous research into autophagy since 2010. In 2013, the team published a paper about autophagic melanosome degradation.

That research found that autophagy had a significant role in determining skin colour by regulating melanosome degradation in Keratinocytes.

Since then, Kao has claimed to have been leading autophagy research studies in the field of skin science to study its applications related to skin care.

Kao said it would continue to invest in its autophagy research in order to drive the development of more new innovations.

“Kao will continue developments of novel technologies for skin beauty and health by continuing research of autophagy, an essential function in the human body​.”