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Melatonin And The Pineal Gland Essay Research

Paper

Set deep in our brains is a tiny gland called the pineal gland. This tiny gland is in charge of the endocrine system, the glandular system that controls most of our bodily functions. The pineal runs our body clocks+, and it produces melatonin; the hormone that may prove to be the biggest medical discovery since penicilin, and the key to controlling the aging process. The pineal gland controls such functions as our sleeping cycle and the change of body temperature that we undergo with the changing seasons. It tells animals when to migrate north and south, and when to grow or shed heavy coats. By slowing down and speeding up their metabolisms, it tells them when to fatten up for hibernation, and when to wake up from hibernation in the spring.

Melatonin is the hormone that controls not only when we feel sleepy, but the rate at which we age, when we go through puberty, and how well our immune systems fend off diseases. Being set in the middle of our brains, the pineal gland has no direct access to sunlight. Our eyes send it a message of how much sunlight they see, and when it+s dark. The sunlight prohibits the gland from producing melatonin, so at night, when there+s no sun, the sleep-inducing hormone is released into our bodies. Because of the pineal gland and melatonin, humans have known to sleep at night and wake during the day since long before the age of alarm clocks.

Humans don+t produce melatonin right from birth; it is transfered in utero to babies through the placenta. For their first few days of life, babies still have to receive it from breast milk. Our levels of melatonin peak during childhood, then decrease at the beginning of puberty, so that other hormones can take control of our bodies. As we get older, the amount of melatonin we produce continues to decrease until at age 60, we produce about half as much as we did at age 20. With the rapid decrease from about age 50 on, the effects of old age quickly become more visible and physically evident. With what scientists have recently discovered, we may very soon be able to harness melatonin to slow down aging, fend off disease, and keep us feeling generally healthy and energetic; not to mention the things melatonin can do for us right now like curing insomnia and regulating sleeping patterns, eliminating the effects of jet-lag, and relieving every day stress.

Melatonin is known as the |regulator of regulatorsX, because it sends out the messages that control the amounts of all the different hormones in our bodies. It is a balance among our different hormones that keeps us healthy, and as we age, our different hormone levels can become unbalanced, which results in aging.

Everything our bodies do requires energy, from running a mile to sitting still and just breathing. Every cell in our bodies requires at least some energy to function. Within all of our cells are microscopic structures called mitochondria. Mitochondria are considered the powerhouses of the cells, because they convert energy into ATP; the substance which fuels most every cell in our body. In order to create ATP, we need to take in and burn+ oxygen. As we age, our mitochondria age, and as our mitochondria age, their production of ATP slows, which results in the buildup of excess oxygen. This buildup results in the oxidization, (or rusting) of the cells and their different components. This is why when we+re older, we don+t have as much energy as when we+re young. Here+s where melatonin steps in. Melatonin metabolizes the thyroid hormone (which supplies energy to the mitochondria, among other cell organelles) so that it carries more energy. When the mitochondria receive more power from the thyroid hormone, they can produce more ATP, giving more energy to every cell in our bodies, and they use up all of the oxygen that we take in, so that our cells don+t begin to oxidize.

There are mitochondria in the cells of the pineal gland, which give it the power to produce and secrete melatonin. Pineal function declines as its cells+ mitochondria provide it with less ATP, and instead start to produce calcium salt, which calcifies the gland. Calcification is the hardening of the gland (with calcium deposits) which hinders its performance. Once the pineal gland begins to function less perfectly, the production of energy for the entire body is thrown off. Therefore, with age comes less energy, which leads to less melatonin, which leads to less energy and more leftover oxygen, which causes aging. To stop this vicious cycle from beginning, one must only take enough of a dose of melatonin to keep the levels of all the involved hormones where they are when we are young.

That only touches on the surface of what regulated melatonin levels can achieve. The calcification that adversely affects the pineal gland happens elsewhere in the body as the mitochondria in the various types of cells slow down. For example, calcium deposits in the blood vessels leads to hardening of the arteries, which can eventually lead to a stroke or heart attack. These same kinds of calcium deposits are also found in such organs as the heart and brain, and can lead to other complications. The reason that children aren+t afflicted with these conditions is that levels of melatonin in the human body are at their peak during our childhood.

To sum up, when the pineal can no longer do its job, it results in the breakdown of mitochondria throughout the body, the powerhouses of the cells that regulate energy. When the mitochondria break down, this causes a chain reaction throughout the body that leads to the eventual collapse of all other organ systems. This collapse is what defines aging to us, and melatonin is the tool we can use to prevent it, or at least put it off a while longer.

It is also being said that melatonin is an effective weapon against disease, and can strengthen our immune systems. Part of this is simply logical reasoning when the effects of melatonin on aging are taken into consideration. It is a decline in the functions of our vital organs that leads to many of the diseases known to man. Therefore, when the aging of our individual organs is hindered, as described in the first part of this paper, the diseases that often accompany that aging will no longer be able to do so. Melatonin will also effect various afflictions in the same way as it would effect atherosclerosis (hardening of the arteries); with melatonin levels increased, the excess calcium salt that can cause so many problems is no longer present to cause them.

The way in which melatonin effects our actual immune systems is slightly more complex. One main cell of the immune system is the white blood cell. One type of white blood cell is a lymphocyte, and one type of lymphocyte is known as a T cell. T cells are responsible not only for protecting cells against viruses and bacteria, but also for ferreting out possible trouble-making agents within our bloodstream. These cells have to be very finely tuned so that they don+t attack any of the helpful cells or materials in our bodies. It would be disasterous if our immune system started to kill the cells that make up the tissue of our various organs, or if it attacked the nutrients we derive from the food we eat. This sometimes happens; disorders like this are known as autoimmune diseases.

The reason for autoimmune diseases, and for the greater frequency and severity of illnesses in older people, is the aging of the immune system. Certain T cells have memories, which is why many times after a person has had a particular infection, they are often immune when later exposed to the bacteria that caused the original infection. The main effect of aging on the immune system is that our T cells can no longer remember what cells are harmful to us, and can no longer distinguish our body+s cells from harmful invading ones. We have supressor cells, to stop attacks on our own bodies that our immune systems may mistakenly launch. However, when we age, our supressor cells can fail to work well or at all.

As it has been demonstrated, it is age itself that leads to most of the afflictions about which I+ve written, and it has been described how melatonin can slow the aging process and its effects. In this same way, it can keep our T cells and the other various parts of our immune system working at a peak physical (youthful) level. With our immune systems working as efficiently at the age of 50 as they did when we were 10, the illnesses associated with old age will seldom be of concern to us, thanks to melatonin.

Besides helping us to live longer and to fend off diseases better, melatonin supplements can help with more commonplace things like stress, jet-lag, and everyday fatigue. Stress isn+t just an abstract idea caused by bad feelings, it+s indirectly created by chemical reactions within our bodies, as a result of perfectly normal situations. Humans have basic survival instincts that we+ve had since the beginning of mankind. When faced with a threatening situation, we have a fight or flight+ urge; the urge to react either offensively or defensively to the threat. What happens is that our nervous system stimulates our adrenal glands, which produce adrenaline, which causes our metabolism to speed up, our muscles to tense, our heart to beat faster, which often causes us to become hot or start to sweat, and often to produce excess stomach acid. In this day and age, however, we can+t always release this tension the way that our body may intend us to. For example, in a threatening confrontation with a teacher, I could niether punch my teacher or run away from him. Therefore, the hormones floating around in my body making me all excited and wanting to react don+t achieve their objective and remain in my body. This is how stress occurs, on both a chemical and emotional level; our impulses are not able to be acted on, and unresolved they do us harm. Melatonin neutralizes adrenaline and other excitement hormones, thereby calming us down. That means no tense knots of muscle from an unrelieved situation, and no excess stomach acid creating an ulcer in my stomach.

with regard to jet-lag and energy loss, the answer is closely related to getting more and better sleep. Jet-lag occurs when our body clocks are slow to readjust in a new time zone; the clock on the wall tells us that it+s a different time than our bodies think it is. I+ve already explained how melatonin causes us to sleep, so when you+re on the plane to wherever you+re going, or maybe the day before you leave, you take enough melatonin so that your body thinks it+s time to go to sleep according to what time it is wherever you+re traveling to. That way, when you get there, you+re already on the same schedule as the people there.

Once again, not having enough energy to make it through a normal day is often the result of not having had a good enough sleep the night before. Melatonin helps us to sleep more soundly, therefore eliminating this problem, so long as we leave time so that we can get as much sleep as we need.

Melatonin is a hormone secreted by a tiny gland deep in the middle of our heads, but having supplemental doses can accomplish great things for us. We can look forward to such great things as extending the length of our lifetimes. We can live those extra years feeling healthy and young, and with much less threat of illness. We can accomplish such useful and even-more-immediate goals like curing jet-lag, improving the quality of the sleep we get, and cutting down on the stress in our lives by both chemical and emotional means. While the study of melatonin and its many miraculous uses has gone on for many years, it must still go on for many more, to determine with more exactness the effects of the hormone on a long-term basis. However, if it only provides a healthy good night+s sleep, it+s a great discovery; but if it will really do all that we think it can, it will be one the greatest medical discoveries of our time.

Bibliography

1. Your Body+s Natural Wonder Drug: Melatonin, by Russel J. Reiter,Ph.D. and Jo Robinson

Copywrite 1995 Bantam Books, Ny, NY

2. The Melatonin Miracle,

3. Melatonin, by Geoffrey Cowley; Newsweek, Aug. 7, 1995

4. The World Book Encyclopedia, World Book, Inc., 1981, Chicago, Il

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