Cool and sweet

Another elegant process that has evolved as part of the endocrine system is that of RECEPTORS. Here we have glucose entering the cell through the action of insulin.
Glucose receptors, which are actually protein molecules incorporated into cell membranes, are like locks crafted for a very specific key. These keys, also proteins such as hormones (in this case insulin) and neurotransmitters, unlock the "door" into the cell and activate a second messenger which then "does its stuff"--creating energy from glucose and oxygen for other cellular processes.
It's simple, really, but incredibly versatile, as the thousands of processes that use similar systems demonstrate. Be kind to your receptors this weekend--they are very sensitive to and can be damaged by poisons such as alcohol, nicotine, other drugs, and real physiologic stress.

Freaked out...

...NOT!

A number of medical terms have been appropriated by the vernacular, to the detriment of effective communication.
"Stress" is one of those terms.
Biologically, stress means that the
body's homeostatic mechanisms are being challenged by environmental factors; it is manifested by PHYSIOLOGIC changes, such as increased heart rate, sweating, and GI distress. These changes are mediated by the autonomic nervous system, which acts in large part through endocrine organs such as the adrenals, the pancreas, and the thyroid.
Simply being upset is not being stressed; it is the physiologic syndrome of stress that is dangerous to one's homeostasis (health). Emotions--mediated by neurotransmitters--can produce stress, yes, but if someone says he or she is "freaked out" from stress and has a normal heart rate and blood pressure, they aren't. Stressed, that is--emotions are real and should be taken seriously but if they have not been translated into physiologic parameters they are not harmful to the body!

On a desert islet...

...of Langherhans?
Undoubtedly the most innocuous of cell clusters, these endocrine islands in the exocrine pancreas produce two of the most critical proteins in the body--insulin and glucagon.
After oxygen, glucose is the most important substance required by our cells with which they do their jobs. Without glucose oxygen is useless (and vice versa). No glucose, no Kreb's cycle, no ox phos, no E, no us.
So, despite what the food faddists say, simple sugar is the key to life. As with all of our carefully calibrated systems, balance is necessary, but in the end we are the organism glucose built. Have some today! (And don't forget the OXYGEN!)

Riding in its Sella Turcica....

Ode to the Pituitary

O, master gland so mighty
Proudly mounted in that cup,
Controlling all and sundry
You keep me standing up!

Glucose, thyroid, growth, and sex,
All submitted to thy whim,
Were it not for all thy grace
I wouldn't be a him.

Sleeping thou dost give me,
And eating, dinner and sup,
Were it not for cortisol
I'd never getteth up.

So care for me, thou tiny king,
And I will care for thee,
By wearing oft my helmet,
And keeping poison free.

The enemy....

...AMYLOID.
Sounds pretty benign? Well, it is as deadly as any other parasite.
The business of life is making and using proteins. As we age, this process gets a little creaky. Amyloid is an abnormal protein that slowly builds up in various organs over time. It has no beneficial functions--it is truly "gunk". It gets in the way of cells doing their normal business.
It is the substance that causes the plaques and tangles in the brain that disrupt communication and lead to Alzheimer's disease. While it can invade other organs, it is this propensity to build up around neurons that makes this innocuous looking molecule a vicious enemy. There is some evidence that it can be fought, but it will take a lot more research to know how to defeat it. In the meantime, be good to your cells by protecting them from those things that disturb normal protein synthesis. High up on the list of things that do this? Tobacco, alcohol, and illegal drugs. Things that may help the brain cells maintain normal protein synthesis? Rest, exercise, mental exertion (READING!), and, yes, love. Be good to your proteins today!

At last....

Proteins are lovely....

ENDORPHINS:
Synthesize some this weekend.

Location, location, location

DNA makes RNA makes protein makes life.
Changes in DNA nucleotide sequences (mutations) result in changes in proteins that have significant effects on the life processes they control.
A major way in which proteins interact with other proteins, especially receptors, is based on their shape and where they "live". If their amino acid sequence--determined by DNA codons--changes, they cannot go where they need to go and do what they need to do. The life processes of the affected cells change--often for the worse.
Such it is with malignant neoplasms. The changes in positioning of codons and subsequently in amino acid sequence and protein shape result in problems with location--where they can go and what they can do. In the end abnormal proteins and cells wander off to wreck havoc as parasites on the entire body, ultimately killing the host.
Keep track of your proteins today!

Come in, Rangoon....

One type of protein for which our DNA codes is the receptor. We are finding that more and more cellular physiology is based on receptor-signal protein interaction. This can be good in the case of growth hormone, pituitary stimulants, and neurotransmitters.

Our somewhat less than stellar success in treating cancer may be due to the downside of receptor physiology. Receptors allow for cells to "turn on and turn off" in a controlled fashion; cancers cells do neither, very probably due in part to altered receptors. Our current chemotherapeutics go after pretty much all receptors, including healthy ones. Research in this area should prove fruitful; in the meantime, be good to your receptors.

Beautiful but deadly....

CANCER
No word carries with it more fear. But we are making progress; survivors like my beautiful sister are evidence of that.
The cancer cell uses one of the basic properties of normal cells--mitosis--and carries it to lethal extremes. It also seems to deactivate another property that sounds "bad" but is really "good--programmed cell death. Unlimited growth, no death--this type of immortality is fatal to the host.
Understanding the human genome and its relationship to gene regulatory proteins is helping us make progress. Public health has given us the opportunity to live longer, and application of our incredible scientific knowledge may give us the ability to enjoy those added years in a healthier state. Encourage the scientists in your life!

Forget zombies--acids are after us!

The human body's normal pH is slightly alkaline at 7.4.

"WHY?"
Acids dissociate in water to produce protons and negatively charged moieties;
the protons then seek out electrons and as they rip them out of molecules destroy their stable structures. This is particularly damaging to proteins.
Many physiologic and pathophysiologic processes produce acids--lactic acid is just one. Over millions of years our cells have developed a natural buffer system to protect us from melting (remember Raiders of the Lost Ark?).
The result is our natural and exquisitely controlled acid/base system, in which we start out "ahead" with a basic pH.
Fearfully and wonderfully made!

But WHY???

...are we made of salt water?
Because....

DNA makes RNA makes PROTEIN makes...

...life.
Every action in our bodies is controlled and executed through the action of proteins.
Every structure is based on proteins. There are a few common metals thrown in--iron, calcium, phosphorus--but these are only there to assist the proteins in doing their job.
Living......it really is through chemistry.

Ode to the Cell

O, beauteous eukaryote,
Drifting through the salty sea
Of fluid that thou lovest,
Please keep thy functions free!

Homeostasis is thy goal for me,
As thou thy proteins make,
And oxygen and glucose be
The foodstuffs thou dost take.

But if thou be'est poorly fed
And perfusion thou'est lack,
Aim me for the tea and bed
Until thy grace be back!

Adaptation

Human skin color is a balancing act--darker pigment protects against damage from UV radiation, lighter color prevents against vitamin D deficiency. Across the entire species of Homo sapiens this balancing act is played out with all such genetic traits; the result is that each subpopulation of indigenous peoples is best suited to its environment.
Beautiful!

Actually...

...as great as DNA is the really cool stuff is RNA.
It is likely that the first coded genome was made of RNA (some viruses still use it) whence evolved proteins and then DNA itself.
RNA transcribes the message of DNA, transfers it outside of the nucleus, creates its own factory, then translates the code into proteins, which make life.
DNA makes RNA makes protein.
But the key step is RNA.
Be kind to yours today!

Beauty!