Michael Fossel Michael is President of Telocyte

March 27, 2018

Aging and Disease: 2.1 – Cell senescence, Why Cells Divide

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 on cell division, then why do some people’s cells divide more than other people’s cells? Why don’t people age at the same rate?

Why does he look old, but she doesn’t, even at the same “age”?

And why do our own organs and tissues age at different rates? We’ve all seen people whose skin looks old, but they have no evidence of osteoarthritis or dementia; equally, we’ve seen other people with terrible osteoarthritis, but no heart disease or dementia. Not only do we age at different rates when we compare different people, but our tissues sometimes age at different rates even within the same person. If aging is related to cell senescence and cell senescence depends on cell division, then why do people vary internally, having some cells (in one tissue) divide more frequently than other cells (in another tissue)? Why don’t all of our tissues age in parallel?

Why does he have bad knees, but she has a bad heart, even at the same “age”?

The easy – and naïve – answer is to say the magic word “genes” and nod knowingly.

The real – and more complex – answer demands a lot more thought. It requires that we reexamine both the data and our assumptions. It requires, in a word, that we think about what’s really going on. Part of this complex answer begins easily. We notice that people who were exposed to too much sun (and too many sun burns), for example, have skin that ages faster than people who avoided sun damage to their skin, and this is true even with identical genes, as in identical twins. We have discussed the fact that aging is not simple a matter of genes, but it’s a balance between damage and maintenance. “It’s not the years, it’s the miles.” Indeed, the degree to which we pile damage onto our tissues shows a good correlation to how fast those tissues show aging and age-related disease. Most of us know this without really thinking about it. For example, we automatically assume that smoking causes COPD, “bad” diets increase your risk of heart attacks, and so forth. These assumptions are now part of our cultural baggage and (true or not) have attained the status of medical wisdom. In fact, to a large extent these are supported by a fair amount of good evidence, although it’s always a bit more complex than the current culturally accepted facts would have you believe. For example, it may or may not (depending on the decade we’re talking about) be accepted that dietary cholesterol has a direct impact on the cholesterol deposits in your coronary arteries, but the evidence that dietary intake (unspecified for the moment, but not just cholesterol) has a long-term impact on coronary artery disease is fairly good.

In short, your behavior (diet, exercise, stress, etc.) can accelerate or decelerate not only your overall rate of aging, but the rate of aging (and age-related disease) in a number of specific tissues. To give a few more examples, people engaged in high-impact activities (think basketball) have a higher incidence of osteoarthritis of the knees than do people engaged in low-impact activities (think yoga). People who get repeated head injuries (think pugilists and American football players) have a higher incidence of Alzheimer’s and other dementias. In both of these cases – osteoarthritis and dementia – those at high risk not only have a higher incidence of the age-related disease in old age, but they get the specific age-related disease at a younger age than do those at lower risk. They are both more likely to get the disease and more likely to get it earlier. What this tells us is not surprising: aging is related to what you do behaviorally, not just who you are genetically. In short, it’s not just your genes.

Genes do, of course, play a fundamental role but they do it in complex relationship with the damage that accrues over a lifetime. If you really want to avoid osteoarthritis, you not only want to have parents who never had osteoarthritis, but you want to avoid repetitive high-impacts to your joints. If you really want to avoid dementia, you not only want a double allele of APOE-2 (instead of two APOE-4 alleles), but you want to avoid boxing or playing football. But then if these sorts of behavior cause age-related disease, and cell senescence underlies age-related disease, what is the relationship?

The key relationship is the rate of cell division. If your cells are forced to divide more frequently, you force them to senesce faster. If, for example, you damage your knees (forcing your chondrocytes to divide and replace the damaged cells) then you will accelerate aging in your knees (as those cells divide, lose telomeres, and change gene expression). The more you damage your knee joints, the more rapidly your chondrocytes divide, and the more rapidly you develop osteoarthritis. If you damage your head (forcing glial cells to divide and replace the damaged cells), then you will accelerate aging in your brain (as those cells divide, lose telomeres, and change gene expression). The more you damage your brain, the more rapidly your glial cells divide, and the more rapidly you develop dementia.

The details, the pathology, the reality of these age-related diseases are wildly more complex than this cursory review suggests, but the basic theme is valid. Given equivalent genes, people who engage in a lifestyle that increases cell turnover will increase their rate of aging. Likewise, your particular lifestyle may increase cell turnover preferentially in one organ or tissue and that will accelerate the rate at which that organ or tissue develops age-related disease.

Any cell in your body (in any tissue) has a baseline “rate of cell division” (i.e., rate of tissue aging). Skin cells, gastrointestinal lining cells, and hematopoietic stem cells divide frequently, while neurons, muscle cells, etc. divide very infrequently in the adult (an in some cases, not at all). Anything that accelerates cell division, accelerates aging. Anytime you increase the rate of damage to a tissue, you increase the rate of cell division (i.e., the rate of tissue aging) and the result is increased aging and increased age-related disease. The same is true between individuals. We each (based on our own genetics) have what you might think of as a “baseline rate of aging” for our body. If you take care of yourself, you still age inexorably, but relatively slowly. If you engage in a high-risk lifestyle, you will age not only inexorably, but relatively quickly.

Aging is caused by cell senescence and cell senescence is cause by cell division, but while you need your cells to divide in order to survive, the relative rate of cell division is, to an extent, controlled by your lifestyle. Cells divide because you’re alive, but the way you live has an impact on how fact those cells divide and how fast you age.

So, let’s answer our initial question. We have been making the case that aging occurs because cells divide, shortening telomeres, which changes gene expression, which results in dysfunctional cells, dysfunctional tissues, and tissue aging (and disease). This is true, but it begs the question of “if cell division causes aging, then what causes cell division?”

The answer is that cell division is both a natural result of being you (your genes, your personality, your culture, and the simple fact that you are alive and some of your cells MUST divide to keep you alive) and the result of what you do to yourself. You have a baseline rate of cell division (and hence aging). If you have a high-risk lifestyle, you age faster; if you have a low-risk lifestyle, you age a bit more slowly. You can increase or decrease your rate of aging – to a degree – depending on what you do. There is (so far) nothing you can do to STOP aging, but can certainly make it a bit slower, or a lot faster.

Next time: 2.2 Cell senescence, Telomeres

January 23, 2018

Aging and Disease: 0.1 – A Prologue

Aging and Disease

0.1 – A Prologue

Over the past 20 years, I have published numerous articles, chapters, and books explaining how aging and age-related disease work, as well as the potential for intervention in both aging and age-related disease. The first of these publications was Reversing Human Aging (1996), followed by my articles in JAMA (the Journal of the American Medical Association) in 1997 and 1998. Twenty years ago, it was my fervent hope that these initial forays, the first publications to ever describe not only how the aging process occurs, but the prospects for effective clinical intervention, would trigger interest, growing understanding, and clinical trials to cure age-related disease. Since then, I have published a what is still the only medical textbook on this topic (Cells, Aging, and Human Disease, 2004), as well as a more recently lauded book (The Telomerase Revolution, 2015) that explains aging and disease, as well as how we can intervene in both. While the reality of a clinical intervention has been slow to come to fruition, we now have the tools to accomplish those human trials and finally move into the clinic. In short, we now have the ability to intervene in aging and age-related disease.

Although we now have the tools, understanding has lagged a bit for most people. This knowledge and acceptance have been held back by any number of misconceptions, such as the idea that “telomeres fray and the chromosomes come apart” or that aging is controlled by telomere length (rather than the changes in telomere lengths). Academics have not been immune to these errors. For example, most current academic papers persist in measuring peripheral blood cell telomeres as though such cells were an adequate measure of tissue telomeres or in some way related to the most common age-related diseases. Peripheral telomeres are largely independent of the telomeres in our coronary arteries and in our brains and it is our arteries and our brains that cause most age-related deaths, not our white blood cells. The major problem, howevere, lies in understanding the subtlety of the aging process. Most people, even academics, researchers, and physicians, persist in seeing aging as mere entropy, when the reality is far more elusive and far more complex. Simplistic beliefs, faulty assumptions, and blindly-held premises are the blinders that have kept us powerless for so long.

It is time to tell the whole story.

While my time is not my own – I’d rather begin our upcoming human trials and demonstrate that we can cure Alzhiemer’s disease than merely talk about all of this – I will use this blog for a series of more than 30 mini-lectures that will take us all the way from “chromosomes to nursing homes”. We will start with an overview of aging itself, then focus in upon what actually happens in human cells as they undergo senesceence, then finally move downstream and look at how these senescent changes result in day-to-day human aging and age-relate disease. In so doing, when we discuss cell aging, we will get down into the nitty-gritty of ROS, mitochondria, gene expression, leaky membranes, scavenger molecules, molecular turnover, collagen, beta amyloid, mutations, gene repair, as well as the mathematics of all of this. Similarly, when we discuss human disease, we will get down into the basic pathology of cancer, atherosclerosis, Alzheimer’s, osteoporosis, osteoarthritis, and all “the heart-ache and the thousand natural shocks that flesh is heir to”. We will look at endothelial cells and subendothelial cells, glial cells and neurons, osteoclasts and osteoblasts, fibroblasts and keratinocytes, chondrocytes, and a host of other players whose failure results in what we commonly think of aging.

I hope that you’ll join me as we, slowly, carefully, unravel the mysteries of aging, the complexities of age-related disease, and the prospects for effective intervention.

December 7, 2015

21st Century Science: Isn’t It About Time?

The other day I was asked about the role of denaturation of a particular protein in aging. It was a typical question that pretty much sums up the problem we have had in understanding (and doing anything about) aging during the past century. The problem is the question hides a flawed premise. It presupposes that molecules simply sit around and accrue damage. Put another way, the problem is that we look at molecules as part of as static pool rather than looking at the dynamic turnover that is the hallmark of metabolism.

Imagine a 1930 Duesenberg that has been lovingly cared for and is in pristine condition, even though it rolled off the assembly line 85 years ago. Compare this to my two-year-old car that already has a few rust spots. Was the Duesenberg better made than my car, that is, did it come with “better genes”? Was the Duesenberg exposed to less damage than my car, that is, did it have “fewer free radicals, less denaturing of its proteins, or a smaller rate of cross-linking”? No. The difference between that “ageless” Duesenberg and my own “aging” car is not the quality of the production line nor the exposure to sun, snow, salt, and dirt. The difference lies exclusively in the dynamics of its care. That Duesenberg was polished, aligned, oiled, repainted, repaired, and “recycled” on a regular basis. My own car is “aging faster” because I don’t care for it as frequently or as carefully as did the owners of that Duesenberg, and therein lies the entire difference between young organisms and old ones.

In aging organisms, it’s neither the genes nor the damage, but the slowing rate of recycling and repair that results in old cells, old tissues, old organisms, and age-related diseases.

Bizarrely and ironically, most people still look at biological systems and ignore the fact that they are alive, that they are dynamic, that they are constantly in flux. We look at a particular molecule – whether beta amyloid, collagen, GDF-11, or a thousand others – and we ignore the fact that these molecules are constantly being created, broken down, and replaced, but instead, we blindly focus on the damage itself. It’s true that as an organism ages any given pool of molecules shows an increase in damage – such as the aggregates of beta amyloid in early plaque formation – but the key is not the damage, the key is the slowing of the metabolic turnover. An accumulation of damage is not static and passively accumulative; it occurs because the rate of turnover falls as a result of changes in the pattern of gene expression. Whether we look at tau proteins, elastin, or any other molecular pool you want to look at, the key to the problem lies not in any particular gene nor in any particular source of damage. The key lies in the rate at which both anabolism and catabolism are replacing those molecules.

We don’t age because we accumulate damage, we accumulate damage because aging permits damage to accumulate.

A doctrinaire attention to “aging genes” and a catalog of one’s favorite sources of molecular damage will never result in cures to age-related disease. The key to intervention lies in the rate of molecular turnover, which responds to changing patterns of gene expression. Those who focus on genes and damage, to the exclusion of molecular turnover and gene expression, are perhaps some of our most highly-educated and intelligent minds of the 20th century…

…but it’s now the 21st century.

It’s time we caught up.

October 30, 2015

Chaos, traffic, and Alzheimer’s disease

We’re going to take an odd detour into both chaos theory and traffic flow in order to understand Alzheimer’s disease, so fasten your seatbelt. The key cascade of pathology that we’re going to look at (and explain) is the presence of beta amyloid plaques in patients with Alzheimer’s, but the principle applies equally to tau tangles and several other hallmarks of pathology seen in aging human patients with cognitive decline. Chaos theory and traffic flow will serve as useful analogies and help clarify the dynamics involved in human pathology, as well as potential cures.

To start with, let’s consider a simple example of chaos theory, in which a continual, linear event results in a sudden inflection and an unexpected, non-linear outcome. Imagine that you are trying to retrieve your iPhone in the middle of the night in order to listen to, for example, an audible book. The lights are out, your spouse is asleep and you gently pull on the earphones, using them to pull the iPhone toward you. Realizing that the slower you pull it, the less noise you make (and the less likely it is that you will waken your spouse), you provide a very slow, gentle traction. Unfortunately, the iPhone is on the bedside table and once it gets to the edge, it suddenly falls and produces a terrible racket, regardless of how slowly and quietly you’ve pulled it up until you reached the edge. The point here is that regardless of how noise and speed were related until you got to the edge of the table, there will come a sudden inflection point with an unexpected and non-linear increase in noise. In short, the amount of noise correlates linearly with speed until the inflection occurs and then the relationship between speed and noise becomes suddenly non-linear. As we will see, much the same thing happens to the clearance of beta amyloid (or tau tangles) and its relationship to neuronal death. Things seem to be going fine until some inflection point is reached, after which there is a sudden, unexpected inflection and the pathology (and cognitive decline) begins.

For the next analogy, consider traffic flow and construction slowdowns. Commuting to work each day, you (and the traffic generally) are moving along at a steady 55 mph as you approach an area of construction. In this area, the traffic slows to a speed averaging 10 mph, as a result of a traffic light at which the speed is 20 mph half the time (green light) and zero half the time (red light). However, you notice that despite this construction slowdown (which has been going on for several weeks), the traffic congestion always becomes noticeable at about the same spot and it never actually backs up indefinitely (as it might if the road was completely closed while traffic continued to arrive). As you think about it, you realize that the actual speed (55 mph versus 10 mph) isn’t the key here. The key question is the number of cars passing per unit time as they approach and as they go through the congested area. If the 55 mph cars are approaching at a rate of (say) 30 cars per minute (with a good distance between them) and the 10 mph cars are getting through the construction and the traffic light at the exact same rate of 30 cars per minute (although they are almost bumper-to-bumper), then the line of slow moving cars will only grow to a certain length before it achieves an equilibrium. We might find, for example, that despite the traffic congestion and as long as the number of cars passing each point per unit time remains equal (e.g., 30 cars per minute, regardless of how close the cars are to one another), then the line will only grow so far and no further.

But this is only true to a point.

It might be, for example, that (as long as the number of cars per minute is equal both coming into and leaving the traffic congestion) the line will be a half-mile long if the construction zone has an average speed of 15 miles an hour twice as long at 10 miles an hour, but there comes a point – perhaps at 9 miles per hour, when the line suddenly has an inflection point and begins to grow wildly (and non-linearly) because the number of cars leaving per minute has no fallen below the number of cars arriving per minute. The relationship between speed (going through construction) and the length of the traffic line was linear until some critical point, at which the relationship took an inflection, the traffic backs up, and all hell breaks loose. Not merely an example of chaos theory, but chaos in action as traffic gridlock ensues.

Much the same is occurring in the brain as it ages. Microglial cells are perfectly adept at clearing beta amyloid as it is produced. Even as these cells senesce and their rate of clearance falls, the backup of beta amyloid “traffic” is not bad enough to cause pathology and it does not trigger neuronal death – or clinical Alzheimer’s disease. There comes a point, however, when chaos theory enters the picture, a sudden inflection occurs, neuronal death ensues, and inexorable cognitive decline becomes obvious.

Think of it this way. The key questions (with beta amyloid as an example) are these: 1) how fast is beta amyloid being produced (how many cars are coming down the highway per minute), 2) how likely are the beta amyloid molecules to be abnormal perhaps because of APOE4 genes (how fast are the cars moving), and 3) how well are the senescing microglia able to clear the beta amyloid molecules (how many cars can they get through the construction area per minute)?

These same questions play a role in understanding why current interventions (e.g., monoclonal antibodies) fail and why we might want to intervene directly in cell senescence. Most current experimental approaches, such a monoclonal antibodies, only serve to “tow away some of the backed-up cars in the traffic line”, while the critical variable is our ability to move cars through the area of congestion. In short, the problem is not a static one (can we remove cars), but a dynamic one (can we keep the cars moving). Once we get a problem with traffic flow (a non-linear accumulation of beta amyloid plaques), the key intervention is not “towing away cars”, but increasing the flow of traffic through the congested area. We should be treating microglia, not beta amyloid.

Curing Alzheimer’s requires that we understand the pathology and not in a naïve, static fashion. If we want to cure Alzheimer’s, we need to improve the traffic, not the cars. The most effective point of intervention is not beta-amyloid but microglia.

Which is how we plan to cure Alzheimer’s.

July 15, 2015

How Does Alzheimer’s Work?

 

Alzheimer’s disease steals our souls.

We lose our humanity when it destroys the neurons that make up a critical part of our brains, but why those neurons die has always remained a mystery since “senility” was first noted, thousands of years ago. Even in the past century, since it was first described clinically by Dr. Alois Alzheimer in a 1907 medical article, we not only haven’t cured the disease, we haven’t even understood it. In this blog, we will come to understand exactly how it works — and what can be done to cure it.

Part of the reason we are slow to understand diseases (and many other things, for that matter) is the tendency to engage in magical thinking. We identify an association, mistake it for a causation, and then we are mystified when our naïve interventions fail. This error may seem obvious, but we make this same mistake repeatedly in medicine and in other aspects of daily life. In the case of Alzheimer’s diseases, we repeatedly identify a protein, a gene, or another product, and we naively try to intervene, then are left clueless and shocked when our best efforts fail utterly. The classic case has been that of beta amyloid plaques, common in most cases of Alzheimer’s disease, when we try to remove or prevent their formation and then cannot understand why all of our interventions fail so spectacularly. There have been hundreds of human trials aimed at beta amyloid, for example, yet none of them have proven effective. Why not?

Alzheimers disease cascade

The reason lies in magical thinking: knowing that some diseases (such as Sickle Cell) are clearly a genetic disease, and knowing that there are genetic correlations with Alzheimer’s disease, we conclude that Alzheimer’s is also a “genetic disease” and that if we could only find just the right gene, we would know how to cure the disease. Unfortunately, Alzheimer’s isn’t a genetic disease. Despite all of the candidate proteins, genes, and gene locations we are still investigating, these are correlations, not the cause of the pathology. Whether we look at beta amyloid (and its precursor protein in several variant forms), presenilin, APOE4, R4YH, UNC5C, SORL1, CLU, CR1, PICALM, TREM2, A2M, GST01 & 02, BAB2, CALHM1, TOMM40, CD33, ADAM10, PLD3, or any of the dozens of other candidates (the list grows longer by the day), none of these “cause” Alzheimer’s disease.

Alzheimer’s is not a genetic disease, Alzheimer’s is an epigenetic disease. All of those genes (I just saw another one published this morning) contribute to the risk, yet none of them — not a single one of the identified genes — causes Alzheimer’s. To quote a previous blog, each of them is a tree, but Alzheimer’s is a forest. When we focus on trees, we forget the broader pathology of the forest.

To use another common analogy, each of the genes identified with Alzheimer’s is like a submerged rock. As we age, the problem is not the hidden genetic rocks — such as APOE4 — but the fact that the water level is gradually falling, until the hidden rocks become exposed and cause a medical shipwreck. Treating APO-E4 will not resolve the problem. Alzheimer’s is not caused by the amyloid protein itself, which is necessary to neuronal function when present in appropriate amounts, but to the failure of amyloid clearance by aging microglia. The aging microglia becomes less and less capable of recycling and maintaining appropriate levels of not only beta amyloid, but a number of other things a well. This becomes apparent earlier in those with an APOE4 gene, but the problem is ubiquitous and not restricted to a single gene product. APOE4 wouldn’t be a problem is the microglial function was up to snuff, as it is in young adults. As the microglia age, as the water level falls, we expose the hidden rocks — the barely sufficient turnover of amyloid proteins in the case of those with two APOE4 alleles. To extend the water analogy, consider the two most well-known of those hidden rocks: APO-E4 and APO-E2. The first (the more dangerous allele) is a rock that lies just a few feet under the water, while the second (the safer allele) is a rock that lies a bit deeper down in the water. Neither of these hidden rocks are a problem when the lake water level is high (i.e., when we are young and our microglial clearance of amyloid is high). However, as the water level falls (i.e., as we age and microglial clearance begins to fall due to epigenetic shifts induced by telomere shortening), we expose first the APO-E4 rock (particularly in those with two copies of the APOE4 gene) and then, much later in life, the APO-E2 rock (in those who are lucky enough to have two copies of the APOE2 gene). Nor are these the only hidden genetic rocks. The rocks include not only the long list of “Alzheimer’s genes” given above, but literally hundreds of other risk factors, factors that become increasingly exposed as our microglia age and fail to protect us. As we age, as the water level falls, we expose risk-after-risk, rock-after-rock, gene-after-gene until we run aground and our minds go down for good.

The solution is not to find each and every genetic rock and hope to prevent disaster by filing down the rocks one-by-one, but to simply raise the water level again. Once we reset gene expression — not only theoretically, but based on animal trials — the pathology resolves. When we go after the key causal element in the pathology, when we reset gene expression in the microglial cells, the neurons are no longer at risk. If we want to cure Alzheimer’s, we need to aim at the cause of the disease, not at the genes, not at the proteins, not at the tangles, not at the microaggregates, and not at the plaques. To date, not one of these approaches has been effective.

Alzheimer’s doesn’t begin in the neurons; Alzheimer’s begins in the microglia. The key to curing Alzheimer’s is not to identify genes, but to reset gene expression and the key to resetting gene expression is to use telomerase therapy.

June 9, 2015

Epigenetic versus Genetic Disease

Last week I attended a global conference on aging research. The presentations were professional and thoughtful, as befits an organization of researchers with impeccable academic and clinical credentials. These are bright, well-educated people who work hard to understand not only the basic science that underlies aging, but the possible interventions that might cure age-related diseases. My role was to consider becoming their executive director and to discuss my thoughts on how to improve — and ensure the viability of — the organization.

Oddly enough, my biggest fear was that they might find themselves side-lined and outmoded by the plethora of advances that are leading the way, advances that promise to revolutionize both our understanding of aging and our ability to treat disease. I had the nightmarish image of a group of well-meaning and well-trained researchers who are blithely marching off the cliff en masse, happy and blind, certain of their small (and ultimately unimportant) piece of the aging puzzle.

The problem is that science changes.

Science has a history of progressing in straight lines until reality abruptly intrudes. We happily refined the epicycles needed to prove a geocentric universe until Galileo substituted a heliocentric universe. We happily refined classical physics until Einstein and quantum mechanics showed us a more complex reality. At the moment, in biology, we happily refine the genetics of disease, while most age-related disease is — as it turns out — actually epigenetic.

Whether we look at the role of APOE4 in Alzheimer’s disease, or the role of cholesterol metabolism is atherosclerosis, a careful view of the literature (and the pathology) shows us that these and other age-related diseases are not genetic in the classical sense. We might reasonably call sickle cell disease genetic, but Alzheimer’s disease is epigenetic. Where genetic diseases are relatively simple to understand, epigenetic diseases are a bit more complex.

An analogy that might help understand the critical difference can be found in my new book, The Telomerase Revolution. Imagine a large lake on which we speed back and forth during our lives. A few of us, unfortunately, have exposed rocks — genetic diseases — that tear out the bottom of our boat, ending our lives. All of us, however, have hidden rocks as well — epigenetic diseases — that are innocuous enough unless we lower the water level. In the case of aging, exactly such a lowering occurs: as telomeres shorten, they change the pattern and extent of gene expression. It is this epigenetic change — lowering the water level — that results in our increasing risk of disease as we age.

Now in the case of a strictly genetic disease — such as sickle cell, we might reasonably ask how we can “fix” the gene. In the case of epigenetic disease — such as Alzheimer’s — however, the problem is not the hidden rocks (the various alleles that associate with Alzheimer’s, such as APOE4), but the fact that the water level is too low. The way to cure Alzheimer’s disease is not to find each and every rock and try to “fix the gene, but to simply raise the level of the water again.

This is precisely the aim of genetic therapy aimed at telomerase.

May 27, 2015

Four Ways to Lengthen Telomeres

Many of you have asked about Helen Blau’s work at Stanford, using telomerase mRNA [FASEB Journal]. Helen sent me a copy of her article when it came out and I’m a serious fan of her work. As some of you know from my upcoming book, The Telomerase Revolution, there are four approaches to resetting telomeres: 1) put in a new telomerase gene, 2) activate the telomerase gene that is already in cells, 3) put in the mRNA (as Helen’s group did) for telomerase, or 4) put in the telomerase protein itself.

 

The first problem with mRNA is that the molecule is incredibly fragile and has a short half-life at body temperature, making it hard to work with in the lab (in vitro) and even harder to work with in patients (in vivo). The second problem (with both mRNA and protein) is that you only get one copy of the final telomerase enzyme, whereas if you put in the gene or activate the gene, you get multiple copies of the enzyme and a lot more “bang for your buck”. In short, mRNA is great, but has a low ROI, clinically speaking. The third problem, a recurrent one in this field, is that if you read either Helen’s paper or the slew of media articles and interviews since publication, the emphasis is always on treating “genetic disease” (such as one of the muscular dystrophies) rather than “aging disease” (such as Alzheimer’s). There is an unspoken and almost universal assumption that genetic diseases like the various muscular dystrophies are “real”, but aging diseases like Alzheimer’s aren’t true “diseases” at all, but they “just happen because things wear out”. This common assumption leads most researchers to focus on inherited genetic conditions exclusively and completely ignore normal aging processes and their associated clinical pathology – such as Alzheimer’s. Even when researchers DO focus on Alzheimer’s they operate on the assumption that it must involve a “bad gene” (such as APOE4).

 

Both assumptions are false, but are shared by most of the academic and medical research community, even if neither assumption is ever clearly stated or acknowledged. Since researchers “know” that aging is not a classic genetic disease, they are equally complacent in thinking that aging diseases cannot be treated by a genetic approach. The result is that almost no one approaches aging diseases in a practical way, using fundamental interventions such as telomerase mRNA, telomerase activation, telomerase protein, or – as in our case at Telocyte – telomerase gene therapy.

May 12, 2015

The Telomerase Revolution

My new book, The Telomerase Revolution, is now finished and is being copy edited by the publisher. Oddly enough, it’s already selling well in preorders. Amazon.com says that it is now the “#1 release in medical research”, which is a delightful surprise, since it won’t actually be published and available to the public until October. For those of you who would like to order a copy, here is the link to Amazon.com:

  • http://www.amazon.com/Telomerase-Revolution-Enzyme-Aging%C2%85-Healthier/dp/194163169X/ref=sr_1_1?ie=UTF8&qid=1426777801&sr=8-1&keywords=telomerase+revolution

The book is a careful and clear discussion of how aging works in cells, how it causes the clinical diseases of aging, and what we can do to cure age-related disease. There is a good clear chapter on vascular aging and neurodegenerative disease — especially Alzheimer’s disease — that a lot of reviewers find especially intriguing. Len Hayflick, the researcher who first described cell aging more than fifty years ago, calls the chapter “superb”. Matt Ridley, author of several best sellers including The Rational Optimist, Genome, and The Red Queen, says that he read the chapter with “real fascination” and tells me “I badly want to read more of the book”.

If anyone would like to do a book review, please contact me, and I will arrange to send you a review copy.

April 15, 2015

Alzheimer’s, Microglia, Mitochondria, and Arginine

Every several weeks, I notice publication of yet another article trumpeting another aspect of Alzheimer’s. Where once it was APOE-4, AB42, or SS31 (an antioxidant peptide), more recent work emphasizes arginine metabolism in the microglia. The good news is that research community has — ponderously and hesitantly — finally begun to shift the clinical focus from the neuron to the microglial cells, a shift that many of us have been pushing for almost two decades. Neuronal damage was always the more obvious pathology, at least under the optical microscope, but it was never the underlying cause of the cascade of damage that results in Alzheimer’s disease. Gradually, we have come to realize that the microglial cells, and often vascular changes, play an early role in starting the avalanche of this horribly tragic pathology.
And yet, even now, it is frustrating to watch how much of the research creeps along, staring myopically down at trivial and secondary problems. It’s not so much that we see the trees and ignore the forest, but that we see the specific lichen on the specific root of a specific type of tree, while missing the interactions and overall pathology that drives the entire forest. The recent focus on arginine is a case in point, but SS31 is a parallel example. In the case of arginine, we notice the microglia; in the case of SS31 we notice the mitochondria, but in both cases we fail to look harder and deeper and we fail to understand the broad processes that drive these changes.
Mitochondrial dysfunction within the microglia is a good example. The dysfunction is not seen in germ cells, nor in young somatic cells, but is prominent in aging somatic cells. How can a germ cell lineage, carrying a line of 1.5 billion year old mitochondria, have normal function, while a somatic cell, having undergone a few dozen divisions in a few dozen years, suddenly have a dysfunctional mitochondria that was doing well for the last few billion years? Actually, we know the answer to that. Not only is it due to changing gene expression within the cell nucleus, slowing the production of many key enzymes needed in the citric acid cycle within the mitochondria, but we know that when we reset this pattern of gene expression in the nucleus, the mitochondria resume normal function. While the aging cell makes less ATP and a higher proportion of ROS as the damaged mitochondrial enzymes permit electrons to “slip” down the chain, but these changes are entirely reversible when we reset telomere lengths within the nucleus.
Nor does it stop there. Just as the aging cell begins to have a lower ATP/ROS ratio, so too do the lipid membranes begin to leak those ROS species, so too do our scavenger enzymes (like SOD) fail to capture those escaped ROS species, and so too do our cells fail to rapidly recycle the molecules damaged by those ROS species. And in every case, these four issues can be traced directly back to the slower turnover induced by a changing pattern of gene expression within the nucleus, which is orchestrated by a gradual telomere loss.
Such changes can be (and have been) reset in human cells, in tissues, and in animal models. So why not reset the microglial telomeres and cure Alzheimer’s?

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