Sirtuins - Anti-Aging Mystery

The greater our comprehension of the aging process the more ways that scientists find to try to extend the average life span. Ironically, the most effective means of anti-aging intervention has been the same for the past 50 years; eating less!!

The results of humans eating a low calorie diet is less dramatic in humans than it is in animals but most experts agree that a well balanced diet with a low caloric level is likely to be beneficial to both the health and the longevity of most people.

Needless to say there is a catch. People have a tendency to avoid doing things that are not easy to do even if they are good for us. For the majority of us, dramatically reducing our food intake makes life too unpleasant to be worth prolonging. To counteract this problem research is being conducted to try to understand why caloric restriction is life enhancing and if the same mechanism can be produced by other means.

The starting point for this study is the idea that caloric restriction extends the lifespan by lowering levels of cell damage by free radicals, which are produced when the cells use nutrients from the mitochondria to make energy. The slowing of the production of free radicals does indeed play a role in this. Additionally caloric restriction seems to set certain cellular mechanisms of self preservation which extends the lifespan of the organism until the amount of food consumed is increased to a level that is sufficient to ensure reproduction.

Caloric restriction and sirtuins

Sirtuins are the class of enzymes that are produced by caloric restriction. The main role of sirtuins is the regular the activity of the many genes that are responsible for the metabolism, cell defense, reproduction and other bodily functions. Sirtuins act as a switch for the body from one mode to another - from self-preservation to stress resistance or from reproductive mode to survival mode. Sirtuins are NAD dependant enzymes that slow the activity of the genes by tightly packing the DNA and are therefore less vulnerable to the cell's gene copying machinery).

The fact that Sirtuins are partially responsible for the life span and effects on health of caloric restriction has lead to the search for a substance that will stimulate sirtuin in the body. An effective sirtuin activator would theoretically provide the multiple benefits of caloric restriction without the hardships.

Resveratol, a sirtuin activator

A possible sirtuin activator has been developed. Unfortunately we don't yet know if it will be good for use in humans. It is called resveratol and is a common substance found in grapes and red wine. Multiple studies have shown that resveratol can have an effect on sirtuins and lengthen lifespan in various species including worms and rodents.

One study published in Nature in 2006 described the work of a group of Harvard scientist who studied the effects of resveratol on obese mice. They used two groups of mice who were both fed a high calorie, high fat diet. One of the groups was given resveratol. The diet began when the mice were a year old (middle aged for mice). The first group rapidly gained weight and many of them developed diabetes and other health issues. The group on the resveratol fared better. While they did gain weight, they did not develop the heath issues that the first group did. They also had a longer life span. Basically, the resveratol acted as a neutralizing force for the excessive caloric intact.

So far resveratol has not been tested on humans so we do not know if it would have the same effects that it did on the mice. An optimal human dosage would have to be calculated. We are still unsure as to whether or not high doses of resveratol would be safe for human consumption or not. One of the other issues with resveratol is that it is not a stable substance and can oxidize relatively easily which means that producing a bioactive, high dose supplement would be an expensive and complex process. All of these issues need to be dealt with before high dose resveratol can be a viable option for sirtuin activation in humans. There are other studies going on to find different, more effective and more stable sirtuin activators.

In the meantime there is not particularly effective way to activate your sirtuins. There are several resveratol supplements available on the market today but the levels are more than likely too low to be particularly effective. The quality and stability of these products are also questionable.

Resveratol as a skin care ingredient

It has been argued by various experts that despite the questions that remain around the use of resveratol to activate sirtuins that if applies topically to the skin it can be beneficial. We know that small doses of resveratol taking orally are safe, as we have been eating grapes and consuming red wine for thousands of years. It seems that this is a possibility that when applied directly to the skin, even in low dosages, there may be enough concentration to set off sirtuin activity in the skin cells. If this is true or not is still open to question.

There are additional uncertainties in the use of topical resveratol aside from the effects on sirtuins. Resveratol is an anti inflammatory and antioxidant, both of which are usually beneficial to the skin. In one study using mice, resveratol lowered some of the signs of free radical damage that had been caused by exposure to ultraviolet light. On the other hand, in another study on human epidermal cells that had been exposed to the same UV light the resveratol actually increased the level of dangerous DNA mutations. Further research is necessary to understand what the net effect of resveratol is on the skin as well as what the proper way to apply it is. If you want to try topical resveratol in spite of the concerns expressed previously in this article you will need to be very care to stay out of the sun, at least until we have a better understanding of resveratol's likelihood to raise the level of UV induced mutations.

Creams with resveratol are available on the market, although the choice isn't very large. The amount of resveratol in these products is generally unknown. It is very difficult to make an effective resveratol cream with a reasonable shelf life. The do-it-yourself method is probably just as viable. It is possible to buy a stabilized resveratol extract and then add the required amount to a topical cream just before you use it, thereby reducing the risk of deterioration of the active ingredients.

Topical sirtuins

There are companies that are claiming to produce creams that contain sirtuins, this would presumably by-pass the need for a sirtuin activator. Keeping in mind the fact that sirtuins are fairly unstable and very large proteins, it would be very difficult to make this sort of cream effectively. At this juncture in time there is no viable evidence that these products claiming to contain sirtuins are effective.

Aging is a complex set of processes that involve a diverse set of conditions and reactions. This is why the aging process has been very difficult to define; it is also why there are multiple theories on the process of aging. The processes of aging can be divided into two groups: the amassing of various degrees of damage to the cells and the genetically programmed process of aging.
Free radicals are the chemicals in the body that have an unpaired electron This means that they are very dangerous as they can behave in a erratic manner which can be very damaging to the effective functioning of the body.
DNA is the critical molecule of life: it is the blueprint of the creature encoded in the genes. DNA is an indispensable part of the cell. Other parts of the cells such as the proteins, lipids and RNA can be replaced if need be. DNA, if lost or damaged cannot be replaced.
Could aging be explained as what happens once cells have reached the Hayflick limit and are no longer able to divide? There is no conclusive answer to that question at this time. It seems that in certain tissues, including the skin and the lining of blood vessels the Hayflick limit may be a key to the aging process.
Is there a centralized aging clock in humans that dictates the pace at which all of the bodily systems run? Yes and No... Studies have not yet found a specific central mechanism that is solely responsible for aging. However, there is a system of development.
Certain substances that contribute to the aging process can be avoided. A good example of this is tobacco tar. Other contributory substances are not as easily avoided as they are key parts of the metabolism. The best example of this is glucose.
The majority of energy that is produced in the cells is done by the mitochondria. Cell function is dependent on the mitochondria providing energy to the rest of the system. Mitochondria are also the main factor behind free radical damage.
One of the most important defense mechanisms in the body is inflammation. It is a key to survival but at the same time appears to add to the pace of aging and the speed of the onset of degenerative diseases.
The body's metabolism produces waste on a regular basis. The majority of bodily waste is expelled through breathing, urine, feces and sweat. The most easily disposable waste is that which is composed of small molecules like urea, carbon dioxide and electrolytes.
Stress has been closely linked to the development of age related diseases and to the aging process as well. Stress response is basically a complicated adaptive reaction in the body.
There are two commonly asked questions about the lifespan of humans. The first is why does the rate of aging differ so dramatically among different species of animals? The second one is why are there more short lived species than long lived ones?
Research on the prolonging of life, studies of people over 100, historical records, and common sense all show us that to live a long life you need to do at least some of the steps in this article.