heres a article dr. michale colgan ( famous nutritionist ) aslo author of famous book optmium sports nutrition , sent me about nitric oxide ( i ask him his feeling on this )
I chose this topic as I have been getting a lot of questions about nitric oxide, so I thought everyone might like to know the real chemistry. There are several l-arginine products on the market claiming to raise nitric oxide levels. This is not really something you want to do if you want to preserve your brain. However, taking l-arginine supplements does not dramatically increase nitric oxide, despite the marketing hype, because the body has built-in controls. If it didn’t, every time you ate some protein food high in l-arginine, your body’s chemistry would be out of control.
Nitric oxide is one of the many gaseous chemicals in the human body, which attest to the old jibe that we are full of hot air. It is manufactured by an enzyme called nitric oxide synthase, which turns the amino acid L-arginine into citrulline and nitric oxide, both of which serve multiple bodily functions. Throughout the brain, nitric oxide is an essential chemical messenger, which improves communication between neurons, release of neurotransmitters, and transmission and storage of information.1,2
Nitric oxide is also a free radical, what is called a reactive nitrogen species (RNS), but is relatively benign.1,3 Like many other biochemicals, however, it can multiply out of control. Then it cooks your brain. It happens like this. Various stressors, such as banging your head against a brick wall, cause certain defensive genes to turn on and cause the brain to manufacture pro-inflammatory gremlins called cytokines. These nasty little beggars stimulate the glial cells to produce large amounts of the inducible form of the enzyme nitric oxide synthase. The enzyme then gobbles up all the spare L-arginine and produces a ton of nitric oxide, which overwhelms other control chemicals and causes raging inflammation. Result: damaged brain cells all around.
If you bang your head ve-r-r-r-y carefully against a brick wall for years on end, as some martial artists do, then, after a while, the defensive genes continue to sleep through it, and no inflammation occurs. So you can take severe blows to the head without much damage. At least that’s the theory. Don’t try this at home.
By Thought Alone
You don’t need a wall or any other blunt object to cause brain damage. A typical brain stressor common to modern urban life, is the automatic fear and anger reaction at a near miss on the freeway. The wise realize they are unhurt, calm down immediately, and move back to the real purpose of life, a state of joyful ease. Those who let their emotions balloon into “road rage,” however, irreversibly damage their own brains.
Numerous animal studies show that fearful and angry thoughts readily cause brain damage, by the same process that occurs with the physical damage from banging your head on a wall. In a new study, representative of the evidence, De Cristobal and colleagues at Universidad Complutense, Madrid, restrained rats, but did not physically harm them. The rats went ballistic with fear and rage, and severely damaged their brains by excess production of nitric oxide.4
Being dumb animals, rats could not understand what was going on. Being not quite so dumb, we know that fear and anger do not exist in any object or situation, but are creations of our own consciousness. Thus, in any event where no physical harm occurs, we always have the choice to avoid negative emotions. By now gentle reader you are coming to appreciate, that by lifestyle choices alone, even your choice of thoughts, you can profoundly influence gene expression, and either protect or endanger the physical structure of your brain.
Air pollution provides a good example of a physical brain stressor just as damaging as a brick wall, yet unfelt and invisible. It is also impossible to avoid in urban life. In a typical recent study by the Toxicology Department of the University of North Carolina, researchers measured the brains of new-born dogs exposed to the air pollution of Mexico City, and compared them with dogs living in an unpolluted area. The dogs living in polluted air, showed large increases in the enzyme nitric oxide synthase, with a consequent cascade of events that damaged neurons throughout the brain. They also showed deposition of plaque and neurofibrillary tangles, and increased apoptosis (cell death), very like those found in Alzheimer’s disease.5
Highly polluted cities such as Los Angeles, New York or Toronto produce similar brain damage in everyone who lives there. I have urged readers in previous books to arrange their lives so as to flee the city, to protect their health against cancer and cardiovascular disease. The new discoveries of unavoidable urban sources of brain damage, give you even more reason for doing so.
The Glutamate – Nitric Oxide Link
Fear, anger and air pollution, also damage the mitochondria and reduce the supply of ATP.2,4,5 The protective electric fences around outer cell membranes lose power, and unwanted substances leak into the cell. Particularly opportunistic is the neurotransmitter glutamate, responsible for fast, excitatory neural transmission, just the sort of brain activity that increases in fear and anger situations. Glutamate attacks what is called the n-methyl-d-aspartate (NMDA) receptors on neurons, making a sort of hole through which calcium and other nasties can leak into the cell.2
Calcium is very nasty when it gets into the wrong place, as anyone who has had a heel spur or a calcified artery can attest. In brain cells it converts an enzyme called xanthine dehydrogenase to xanthine oxidase, a process which produces a mass of superoxide free radicals.6,7 Then all hell breaks loose. The excess nitric oxide already being produced by the brain stressor, combines with the superoxide to make the extremely damaging free radical peroxynitrite (0N00-).6,7 Peroxynitrite damages mitochondria, DNA, other proteins in brain cells and any other tissues that get in its way.6,8
Some of these clues come from recent research on the brain damage caused by drugs such as methamphetamine, damage that is very like early Alzheimer’s. In a representative study, Imam and colleagues at the US National Center for Toxicological Research, in Jefferson, Arkansas, showed that peroxynitrite is the major culprit.8 With every step of evidence, science is tying the brain damage caused by a wide variety of stressors to the major forms of dementia.
Links To Alzheimer’s
Cholinergic neurons in the hippocampus of our basal forebrain, express the neurotransmitter acetylcholine. These cells are more primitive in evolution than cholinergic cells in the cerebral cortex. They evolved in the brains of short-lived, ferocious animals, and are designed for shorter, more violent life than those in the cerebral cortex. They have higher levels of nitric oxide, to speed neural transmission for violent action, and lower levels of endogenous antioxidants, because they did not have to last very long. So they are more vulnerable to damage, and are the first to go in neurodegeneration.
It is exactly these hippocampus structures that show the most damage in Alzheimer’s disease, with large numbers of dead and dying cells, amyloid plaque blocking neural transmission, damage to mitochondrial DNA, and useless tangles of neurofibrils.9 In cell culture studies, the amyloid plaque itself causes further release of nitric oxide, thereby creating a vicious and progressive cycle of damage.10 Alzheimer’s patients also have increased brain levels of inflammatory cytokines, which as we saw above, increase production of nitric oxide even further.11
Links To Other Dementias