In my previous post (1), I highlighted a word I recently came across, autophagy, a word with plenty of air beneath its wings, a word I predict soon will become common in languages around the world. Why? Because autophagy is a vital biological process that, when defective, underlies the development of a myriad of human diseases such as Alzheimer’s, not to mention cardiovascular and infectious diseases, and even certain cancers.

            Autophagy is one very hot scientific topic. Laboratories around the world have published thousands, make that tens of thousands, of papers on the subject. And, as in most areas of science, there are disagreements and inconsistencies.  No wonder. Autophagy is an amazingly complex system within living cells, a process that appears to be adaptable to things we can accomplish to live healthier and longer. Who isn’t interested in that?

            And what exactly is autophagy? To be candid, only those working in the field could begin to answer that. Autophagy includes a full orchestra of biochemical reactions, a system so intricate that even a comprehensive semester course in cell biology would leave questions unanswered. I’ve picked up a few basic facts, and I’m feeling foolish enough to attempt to pass some of them on to you in a few simple paragraphs.

            For those of you better informed on this subject than I, and there likely are a good number, you have two choices. You can keep on reading and snigger as I flounder, or you can abandon ship here.

THE CELL

            The cell is of course a basic unit of life. There are zillions of tiny cells living all around us, independent rascals living on their own, things such as bacteria and yeast cells. These guys get along fine because their outer covering (membrane) is permeable to oxygen and nutrients, so these essentials can enter into the cell’s stew-like interior and be metabolized to produce the energy needed for living. The membrane also allows the waste products of metabolism to pass out of the cell.

            The “stew” in each cell is a moist conglomerate, an astounding labyrinth of complicated chemicals, microscopic pieces and packages that move about in that infinitesimal space as efficiently as robots in an automobile factory. Some pieces and packages found in nearly all cells have names such as a nucleus, Golgi apparatus, lysosome, and mitochondrion, not to mention genes, enzymes, and loads of other stuff I can’t tell you anything about. (See diagram below. Taken from Biomedicines (2), an open source journal.)

            Here’s why all of this is important. Just as any busy factory does, individual cells must deal with their internal parts that become damaged as time goes on. That’s where autophagy shines. It is an intricate recycling system that repairs broken proteins and damaged mitochondria (the particles that generate energy for the cell). And during starvation autophagy digests some of the cells own proteins to survive longer. The process occurring in mitochondria has a special name. It is called mitophagy.

            Not surprisingly autophagy tends to become less efficient as one ages, but evidence suggests there are ways to improve this, exercise being near the top of the list. Please put a check by exercise. That’s an important one to remember. As I said, autophagy seems to ward off inflammation, keep the heart healthy, and reduce degeneration of the brain. More on this later.

            One final basic point here. In order for cells to work efficiently, they must be in a place where oxygen in available, a place where the trash emitted can be carried away. This works fine when a cell is located in, say a pond, but how could this possibly work when some 30 trillion cells are squeezed tightly together, as in a human body?

            I know a bit more about that process. I’ll talk about that in the next post.