There’s great power in biological cell recycling. Your body’s ability to self-digest (autophagy) lets you fight cancer, resist aging, recycle everything from broken cell walls to destroyed viral proteins, kill off pathogens, remake your energy balance, recast most nutrients, and deny diabetes (it also works while you sleep.) It’s high time the Nobel committee recognized the power of garbage remaking, giving this year’s medicine prize to Ohsumi Yashinori of the Tokyo Institute of Science and Technology.
Why is Cellular Garbage So Great?
It’s critical to life. The human body works so quickly it gets used up fast. As Ana Maria Cuervo of Albert Einstein Medical College points out, most of your heart is remade in about three days. It’s must be rapidly replaced, or you and I will literally turn heartless.
This is just the beginning of the work autophagy must accomplish.
For this is not a Browning-Ferris, Waste Management kind of maneuver. Unlike human societies, we can throw out the vital components of our lives to giant into dumps hidden in unlikely, unlucky places. We have to remake and renew almost everything we use.
And that’s what autophagy does. Think for a second of the cell, of which you’ve got ten trillion human ones, as a house. Normally houses last decades.
What if they only lasted days?
That would require very efficient removal of wrecked materiel. But if every house we lived in only lasted a few days, we’d never have the chance nor the environment to make thousands of copies of all the parts inside it – the windows and doorlatches, television sets and showers, pet cages and kitchens.
So autophagy does more than just “break stuff down.” It rapidly begins and moves towards completion the process of remaking and recycling and renewing.
Fortunately for us, the components of a cell are made out of the same materials, like the amino acids of proteins. We break down the stuff of which we are constructed, reconfigure it and reuse it. Yet we do a lot more with autophagy.
What happens when a pathogenic bacterium or virus enters your cell? You have to stop it. Fight it. Destroy it. Recycle the remains.
Autophagy does a major job. The same processes that put a ring around “regular” materials for recycling can be used to fight infection. The phagosomes, big vesicles or bags that “ingest” material for autophagic processes, can be used to ingest invading pathogens. You can even get the invading stuff remade into materials you almost immediately reconfigure to line your cell membrane or control protein synthesis. That’s part of the promise of information health – seeing your body as an endlessly updated information system. Autophagy, reprocessing everything, is a critical part of renewing you – and what makes you.
We may produce dozens of cancers every day, innumerable cancerous cells over a lifetime. Autophagy is used to identify and destroy the cells we want gone. It plays a vital part in programmed cell death, where cells that are too old, too ineffective, or just simply dangerous are given signals to self-destruct – which in many cases comes to mean self-digest.
Aging and Dementia
We hear a lot about amyloid and tau proteins “clogging up” the brain cells of older adults, leading to Alzheimer’s Disease. As I’ve argued before, this is a very oversimplified view of what happens in Alzheimer’s, yet it is true that clumps of material like amyloid do kill cells. Autophagy of amyloid proteins and their associated products normally prevents this. And don’t entirely discount amyloid useful purposes – amyloid proteins may play a critical part in brain cell responses to pathogens as an evolutionarily “early” form of immune response. If amyloid proteins are literally caging harmful bacteria and viruses, you can bet autophagy is a critical part of that infection fighting process, just as autophagy prevents the “clogging” of nerve cells with clumps of junk as occurs in diseases like Parkinsonism and Lewy Body dementia.
Your body is not just fats and proteins, bones and skin. It’s information. How you process the material of life changes life. And it can do so greatly for the better.
Research on autophagy has demonstrated how quickly we remake our bodies. It also has shown how much of our processes of physiology – from clearing away to recycling to remaking and recreating – are deeply integrated with another. Autophagy lets us make more efficient the same “old” molecules, and lets us see our bodies as more dynamic, focused, and malleable than many thought. Health is a profoundly creative process.
So is the process of recycling. We couldn’t live without it.