banner

 

Hunger for the Nobel Prize: Autophagy

by Gopinathan K. Menon
November 15, 2016

When it comes to marketing skin care ingredients, the cosmetic industry has shown the tendency to highlight connections with Nobel Prize winning topics, be it DNA, nitric oxide, or aquaporin. This year, literally and figuratively, the hunger for the Nobel connection has been satiated by the news of the prize being awarded to Yoshinori Ohsumi for his discoveries on the mechanisms of autophagy—self-eating by the cells. Autophagy, an evolutionarily conserved process, is how eukaryotic cells recycle part of themselves, utilizing proteins and organelles that have become damaged or no longer needed. The cells carry out this process by sequestering such proteins and/or organelles in a double membrane vesicle, which fuses with lysosomes (another Nobel winning organelle), digests the contents, and essentially recycles them for cellular energetics and/or synthesizing organelles that are more important at that stage of cell development, especially when starved of nutrients.

illustration of the process of autophagy

Figure 1: Schematic diagram of the steps of autophagy. Reproduced from A. Meléndez and B. Levine, Autophagy in C. elegans (August 24, 2009), WormBook, ed. The C. elegans Research Community, WormBook, doi/10.1895/wormbook.1.147.1, http://www.wormbook.org.

In the last decade, caloric restriction and its implication for sirtuins and longevity has attracted much attention. Likewise, autophagy has also been in the spotlight as a significant cellular process in aging and human health. The term “ autophagy” was used first in the 1960s by Christan de Duve—who identified lysosomes—but the details of the process remained murky until Yoshinori published his discovery of the autophagy genes (15 of them) in yeast, and later cloned these genes in mammalian cells, leading to a virtual explosion of research studies on autophagy and its implications in development as well as normal and abnormal physiological processes, especially its implications in several diseases. Originally identified as a cellular mechanism to combat stress, it is now well accepted that autophagy is operational in cells at the basal level, contributing to homeostasis of cells and organisms. There is a Gordon Research Conference as well as a Keystone Symposium entirely devoted to this topic, which reflects its significance in the academic community and in applied research. Already, some of the leaders in the personal care industry and technology savvy suppliers have developed actives and claims exploiting this cellular adaptive process to combat aging and associated maladies.

As research progress, and with the Nobel spotlight shining on autophagy, terminology and jargon abound, especially of the molecular kind. As to the organelles being devoured, we can find such terms as "mitophagy" (for mitochondria), lipophagy (for lipid droplets), and pexophagy (for peroxisomes). Creative marketers have a lot of room to compete with the scientists; the latter group being hamstrung by peer review.