Reposted from November 27, 2008

Tryptophan is one of eight essential amino acids in the human body.  Essential amino acids are so called not because they are more important to life than the others, but because the body does not synthesize them, making it essential to include them in one’s diet in order to obtain them.

Like other amino acids, tryptophan works as a building block for proteins.  Tryptophan is found in every protein including fish, steak, cheese and eggs.  Tryptophan is required for the synthesis of some specific organic compounds including:

• Serotonin and melatonin (neurotransmitters)
• Niacin (vitamin B3), and
• kynurenines

Serotonin (5-hydroxytryptamine) affects mood, melatonin helps regulate sleep, and kynurenines may be useful in regulating the immune system.

A drug called tranilast, available in Japan as an allergy medication, is chemically similar to kynurenines and shows promise for the treatment of certain autoimmune diseases, including multiple sclerosis.

Turkey isn’t even unusually high in tryptophan. Many foods, such as beef or soybeans, boast higher concentrations (read more and see the table comparing Turkey Tryptophan to other foods after the break).

Turkey sleeping pill

In its purified form and on an empty stomach, tryptophan is a mild sleep-inducing agent and that probably led to the idea that foods containing heavy doses of the chemical cause drowsiness.   While consuming tryptophan-rich foods may cause blood levels of the amino acid to rise, so many other chemicals are also present in a Thanksgiving meal that not enough tryptophan reaches the brain to have a sedative affect.

In the 1980s, the connection between tryptophan serotonin was put to the test in a form of supplements marketed as a sleep aid.  Ater a massive outbreak of an autoimmune disease called eosinophilia-myalgia syndrome, the FDA banned their sale in 1991.

Tens of thousands of people became sick with flu-like symptoms and 37 died.  Most of the cases were attributed to contamination at the manufacturer’s plant, but some researchers still find a connection between high-doses of tryptophan and eosinophilia-myalgia syndrome.

So why the traditional Thanksgiving nap?
The lethargy may be caused by the stressful hustle and bustle of the holidays, alcohol consumption, and the massive caloric intake of the year’s biggest feast.  It takes the body a tremendous amount of energy to break down these foods.  When your stomach is full, blood is directed away from other organ systems, including your nervous system. The result? You will feel the need to snooze after any big meal.

      The future of medicine has begun to focus on the mapping and understanding of biological interactions between molecules as systems.  By mapping out biological systems at the cellular level, scientists hope to understand the causes of disease processes as they occur.  One theory focuses on the idea of nanotechnology.  The underlying idea behind this theory is that each system that regulates our body is based upon a series of interactions between molecules, cells, and environmental influences, much like we know how our brain processes occur by the interactions between firing neurons.  It is thought that by some outside influence, or pattern of information failing to occur normally, this upset in the system will trigger incorrect processes to occur within the system, therefore causing the disease.  As our telephone game in class displayed, if one sequence is off, the normal coding process is flawed, which can cause multiple defects.  For example, an incorrect encoding of our DNA can cause the biological system to incorrectly process the information, and like a chain reaction, cause other incorrect patterns for form, leading to disease.  Environmental influences also can have a profound effect.  Ultraviolet radiation from prolonged sun exposure can cause DNA damage, thus causing an incorrect pattern to be encoded within the skin cells, producing cancer.  By mapping out our biological systems at the most basic level, cellular and molecular, we can understand the normal processes that take place in the biological system for normal and healthy operation.  Moreover, when there is an incorrect process occurring, causing cancer for example, scientists can identify this incorrect process at a very specific and focused point in our system, at the genetic, cellular, and molecular level, and correct or remove this damaged cell or DNA sequence, thus returning the system back to equilibrium and curing the disease. 

      The mapping out of our entire genetic system and each interaction that occurs within a healthy person for example is a large undertaking.  The task is to computer generate a model that understands and records EVERY DNA to RNA, cellular, molecular, and environmental influence that can alter the body’s functioning, both in a perfect and healthy setting, and those that will cause damage or dysfunction; of those in which cause dysfunction and ultimately disease or failure in the biological system, scientists will need to generate a model of each dysfunction, of each environmental influence on every interaction and how they cause the dysfunction, and finally what disease or failure will occur, and come up with a solution.   

“In the next 10 to 20 years, predictive and personalized medicine will be revolutionized by at least two new approaches. The sequence of individual human genomes will permit us to determine with ever increasing accuracy the probable future health of an individual. Inexpensive measurements of blood proteins will permit us to assess, regularly and comprehensively, how that individual’s health is evolving. 

Preventive medicine starts with the identification of proteins within a diseased network that, if perturbed, will restore network behavior to normalcy, and will eventually lead to prophylactic drugs that prevent disease. For instance, a woman at increased risk for ovarian cancer, who at age 30 starts taking a nanotherapeutic that is specially designed to offset the molecular source of the risk, might lower her lifetime chance of developing ovarian cancer from 40 to 2 percent.” (Heath, Davis, Hood, 2009).  
 
 
 

QUESTIONS 

Are there any implications or side effects of using nanotechnology that would cause a dysfunction of the systems itself? 

What would this mean for the world population if many of our diseases would become cured? 

Can this be considered our first step in fighting aging as a disease process in itself? 

Source: Scientific American
 

Java, Joe, Espresso, Coffee, Starbucks…
Whichever you call it, they all contain caffeine, a central nervous system stimulant, that National Geographic Magazine calls the world’s most popular psychoactive drug.

Mechanism of Action:
Caffeine resembles a naturally occurring substance in the brain called adenosine.

Caffeine does have a high attraction (affinity) for adenosine receptors in the nervous system, but caffeine’s effect on the body is not like that of adenosines.  Caffeine blocks access of adenosine to its receptors and thus caffeine is classified as an adenosine antagonist.  The role of adenosine is associated with sedation of parts of the central nervous system.  By blocking the effects of adenosine which puts on the cellular brakes, caffeine is able to provide the jump start many seek with that morning cup of coffee.

Disorders associated with caffeine use include Caffeinism – a clinical syndrome characterized by anxiety, agitation, insomnia and mood changes.  Symptoms include tachycardia, hypertension, cardiac arrhythmias, and gastrointestinal disturbances.

People with anxiety disorders tend to be quite sensitive to the effects of caffeine, especially if they do not develop a tolerance to caffeine’s effects.

Source: Julien, Robert M.  A Primer of Drug Action Tenth Edition

Like other peptide neurotranmitters, Oxytocin is produced from larger protein precursors called polyproteins or prohormones. (Kandel, Schwartz, and Hessell. 288-289.)

In the nervous system, the presence of oxytocin increases Na⁺⁺ secretion.  In the mammary glands, oxytocin causes the contraction of smooth muscles, leading to milk ejection. It is believed that Oxytocin is stimulated by olfactory cues. (Purves, Augustine, Fitzpatrick, Katz et al. Ch 30)

Oxytocin also causes the myometrial muscle smooth muscle to contract. (which are aided by prostaglandins) (Hill, Wise and Anderson. 442)

In the Prairie Vole, oxytocin is released into the brain of the female during mating.  This is attributed with the formation of a monogamous pair bond with her partner.  In the related mountain vole, oxytocin is not released during mating and the mountain vole leads a promisquous lifestyle.

In humans, plasma concentrations of oxytocin have been reported to be higher amongst people who claim to be falling in love. Oxytocin has a role in social behaviors in many species, and so it seems likely that it has similar roles in humans. It has been suggested that deficiencies in oxytocin pathways in the brain might be a feature of autism.

There has been some evidence to suggest that Oxytocin may have been involved in Obsessive Compulsive Disorder or a similar disorder. However, double blind studies have not been able to provide statistically viable data to support this hypothesis.

Disorders wherein levels are elevated or lowered

Excess oxytocin has no known significant problems. A lack of oxytocin may result in a decrease in milk ejection during lactation. (Lapping-Carr)

by Ryan B

There is a tooth-protecting substitute called “xylitol” that has been put into the candy “gummy bears,” which is known as a sweet snack that causes cavities, but in this case, these bears prevent them. The sugar substitute is a natural sugar alcohol that is used as a sweetner. It has been shown to reduce levels of the “mutan streptococci” bacteria that causes gum disease and tooth decay. This particular research was done by Kiet A. Ly, from the University of Washington. More importantly, a children’s study was conducted, where a group of children were given the bears that contained the “xylitol,” three times a day. After six weeks, a drastic change occured which showed the level of MS bacteria found in plaque dropped significantly. Due to this particular tooth-protecting substitute, studies are being conducted all over the United States to further the cause.

Considering that gum disease and tooth decay are one of the major diseases in the world today, this particular discovery has the ability to save many mouths. It is a brilliant idea which will attract kids, because children will want to eat this candy, and at the same time they will be enjoying as sweet snack as well as preventing decay in their mouths. Hopefully, using a tooth brush will no longer exist, and eating “ant-tooth decay” candy will take over.

Chemical structure of XYLITOL

Source: http://www.biologynews.net/archives/2008/07/27/gummy_bears_that_fight_plaque.html

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