senescent cells

You might be intrigued by an invited paper this week in Alzheimer’s & Dementia, which the editors feel “will change the field”. The paper explains how Alzheimer’s works, why prior trials failed, and offers a novel point of intervention. The paper has already generated more than 100 reprint requests prior to publication. The link to […]

I confess that I’ve yet to find time to continue through each of several age-related diseases. In partial recompense, let me offer the following, which is adapted from the quarterly newsletter that I put out for Telocyte. While it focuses on Alzheimer’s disease, the import is generic, applying to all age-related diseases. How Alzheimer’s works […]

Aging causes disease. To many people, the relationship is even closer: aging is a disease. The latter view is controversial. Most biologists and physicians would view aging as a “natural process” and contend that “normal aging” is independent of disease. Aging, in this view is not a disease, although it certainly causes disease. They often […]

The human body represents a “system” in the engineering sense: all parts (cells, tissues, organs) are interdependent. To understand how the body functions (and how it ages), we may appropriately study individual cells, but we must also study the interactions between cells. We may start by looking at small communities of cells (local, homogenous tissues), […]

The human body contains perhaps a bit short of 40 trillion cells, which is an impressive number, yet a large part of our body – a quarter to a third, depending how you measure it – isn’t intracellular, but extracellular. This includes not only the fluids within the blood and lymphatic spaces, but the space […]

Many people assume that mitochondria (and free radicals) lie at the heart of aging or that they are “the cause” of aging. Despite having a central role in aging, the assumption that mitochondria cause aging is both simplistic and – not to put too fine a point on it – is totally at odds with […]

Why are we more likely to get cancer as we age? Not only does the incidence of cancer go up with age, but it goes up exponentially. Why? Moreover, the exponential rise is seen in most species, regardless of their lifespan. It’s not the years, it’s the aging process, regardless of time. Why? The key […]

As the human body is composed of cells, so are cells composed of molecules. It is true that the cell encompasses a plethora of organelles (membranes, mitochondria, nuclei, Golgi bodies, ribosomes, etc.), but each of these organelles is in turn composed of pools of various molecules. Just as cytoplasm is a “soup” of molecules, organelles […]

Effective maintenance is a product of the rate and the quality of the maintenance process. If we look at a car, for example, the long-term condition of the car depends on how often we institute maintenance (once a month or once every few years?) and the quality of the maintenance procedures (do you replace and […]

Changes in gene expression underlie aging and age-related diseases. There is all-but-universal (and equally unwarranted) assumption that both aging and age-related diseases are genetic. We see articles on “aging genes” and “genes that cause Alzheimer’s disease” (or genes that cause heart disease, osteoarthritis, etc.). The reality is that both aging and age-related diseases are not […]

Everyone seems to “know” that telomeres have something to do with aging. The internet even has pop-up ads about foods that lengthen your telomeres, with the unstated assumption that will make your younger, or at least healthier. Inquiry shows, however, that not only do most people have no understanding of the role of telomeres in […]

Why do some people age faster than others? We’ve all seen people – high school reunions come to mind – who have the same chronological age, but different biological ages: with the same “age”, one person looks ten years older (or younger) than another. If aging is related to cell senescence and cell senescence depends […]

Most of us – when we think of cells at all – seldom appreciate that the idea of a “cell” is a modern idea, not quite two centuries old. One of the tenets of cell theory is that cells are the “basic unit of life”. This makes some sense but note that while the components […]

For those interested in knowing where this blog is going (or where it has been), here is an index of all previous and planned posts for this series on Aging and Disease. Note that the planned posts may change as we progress. 0.1 Prologue 1.0 Aging, our purpose, our perspective 1.1 Aging, what is isn’t […]

Misconceptions regarding the current model of aging are rampant and they tend to fall into one of several categories. These include Straw man arguments, unfamiliarity with how age-related human pathology occurs, simplistic views cell senescence, genes, and expression, or misguided approaches to measuring telomeres (usually in the wrong cells). The Earth can’t possibly be round, […]