Introduction to Aging: the Biological Science of Why We Age

Chapter 1, Aging: a Cluster **** of a Topic.

Disclaimer: I'm going to be describing things a little bit differently in this book/series. I think science is best conveyed colloquially. It's best having a conversation with someone versus to have a conversation at them—so that is how things are going to be done here. If you would like a scientific form of discourse, check out the references I will be leaving at the end of each section. The people involved in this field of research are way more experienced, qualified, and intelligent than I am.

Wasn't it Socrates that said a wise man is one who admits he knows nothing? I mean, Socrates was a student of Aristotle and Aristotle believed and helped falsify the "foundational" knowledge that inadvertently was to be kept for at least a thousand years after his time. I'm talking about the concept of gravity. Aristotle believed that by dropping two objects (one heavier than the other), that the heavier object would be the first to hit the ground. Nope. According to the "Theory" of Universal Gravity, that is far from the case. Objects of different mass will fall to the Earth at the same rate, minus their air resistance.

"Why should I read this book?"
What I'm trying to say is, there's no reason for you to read this book/series. I am not entitled for time, and I would never want you to feel like I think that.I do hope you begin reading this book I'm starting out of curiosity. Because, hell, aging is hella cool. However, I want to show you in the next few paragraphs why I think you should read it. So please stick around at least that long 😅 you most certainly don't have to, but it would be nice if you'd let me try to convince you in why this subject is astoundingly interesting. Please be as reluctant or hard-headed as possible. That is afterall, the point of seeing the world with a scientific mind.

"Why are you so obsessed with aging?"
I will get more into me and my reasons 'why' in the next few parts of this book. However, I think this has been way too much didle-daddle. I would like the show to go on for us. So, let's dive into our first topic (and hopefully not the last): aging.

We should probably begin by defining the word aging AND the concept of aging. Because of my background in Literature/Writing, Biology, and Anthropology, I'm glad I got the exposure to these disciplines because I believe they provide me a better universal look at science and the concepts within science.

Chapter 1: Aging, a cluster **** of topics.

What does aging mean (biologically, physiologically, and even etymologically): the simple definition of aging is defined by Google as, "the process of growing old" (Oxford Languages via Google, 02/09/2021). A more complex definition of aging is written by the encyclopedia Britannica as a progression of physiological changes that lead to the decline in function and eventual biological senescence of an organism's ability to adapt to metabolic stress. However, Gilbert Sunderland's Developmental Biology textbook (sixth edition), defines aging as "the time-related deterioration of the physiological functions necessary for survival and fertility. The characteristics of aging—as distinguished from diseases of aging (such as cancer and heart disease)—affect all the individuals of a species" (Sunderland, Developmental Biology, 6th edition).

A regular person reading this would probably be thinking right now, "Wait a minute. These are all the same definition!" But they're not. I assure you. These definitions are not the same. The first definition describes aging from an etymological perspective. Whereas the Britannica description of aging discusses the physiological consequences of aging AND the metabolic consequences associated with and which cause, aging. Sunderland's definition is what would be taught in a Developmental Biology (DB) course for undergraduate or graduate students (from a DB-perspective).

"I call it the law of the instrument, and it may be formulated as follows: Give a small boy a hammer, and he will find that everything he encounters needs pounding." — Abraham Kaplan.

Aging is defined by the field/perspective/lens it is studied through. There are many perspectives to aging. One is the free-radical theory of aging (FRTA). FRTA states that through natural metabolism (converting organic molecules into chemical energy i.e. digesting and metabolizing food), an organism will slowly accumulate free-radical damage. This free-radical damage is caused primarily through the free-electron caused by creating adenosine triphosphate (ATP) at the end of the electron transport chain (a process known as oxidative phosphorylation), where 36 or 38 ATP molecules are generated for every molecule of glucose (C₆H₁₂O₆).

That segment above is referred known as the FRTA definition of aging. The other is known as the Disposable Soma Theory of Aging (DSTA). DSTA describes aging as the beginnings of the end-stages of reproduction. This means that once an organism is no longer capable of reproducing. Once reproduction for the organism stops, the organism begins aging. Menopause is an example of the DSTA phenomenon for females. Whereas for men. decreasing testosterone levels will contribute to a decrease in e luteinizing hormone (LH) and follicle stimulating hormone (FSH), which in turn decreases sperm production and quality). Hence DSTA can also be combined with the Rate-of-Living Theory of Aging (RLTA), the Neuroendocrine Theory of Aging (NTA), and the Antagonistic Pleiotropy Theory of Aging (APTA). There are plenty of other definitions for aging. We'll touch on those and I will certainly answer questions that may appear in terms of those subjects related to this text.

Now, let's move away from the Theories of Aging and begin looking at some of the genes that play a role in the process. Once we have an understanding of the DNA or gene expression levels of aging, we'll be able to understand all the theories better i.e. the theories will be discussed more in-depth than what they are discussed at now.

Remember the name of this chapter? Aging is a cluster **** of a topic. It is so vast and immense that not many scientists will undertake its research or many grant-giving institutions allow a researcher to conduct research on aging without first defining what it actually is. As we saw from the slight and brief survey of aging discussed above, defining aging is still a highly debated topic. This is why researchers just pick a physiological consequence of aging (arthritis or osteoporosis for weakening joint and/or bone density) or symptoms related to aging (diabetes causing widespread inflammation will lead to early-aging). There are plenty of other diseases associated with aging, such as progeria (leads to the premature aging of a toddler/child, which leads to a very early death).

The first class of aging molecules we'll discuss in the next section will be Sirtuins. They have been studied extensively and are involved in numerous pathways ranging from cellular to developmental to metabolic and much much more. We'll quickly get into the brief history of sirtuins and then begin tackling the subject—learning more as we go rather than giving you a brick of information I refer to as "prehistory" before even touching a topic (an awful way to teach IMHO).

So, I hope you enjoyed the first part of this series and I hope to see you again soon! Until then.

Chapter 1 references: [I have them but I would like this to be published to Wattpadd first because citations take me years to do.]