The Human Body: Aging

'Important Factors in Aging'

-Testosterone
-Brain Aging
-Eyes Aging
-Joints Aging
-Keeping Joints Lubricated
-Kidney Failure

Testosterone/Progestrone

- Alpha Male

When the Alpha Male reaches age 32 the testosterone (hormone) levels drop 7 percent.
83% of the testosterone (hormone) is created in the testes (testicles).
In which the pituitary gland (in the back of the base of the brain) signals testicles to produce the testosterone hormone.


The testosterone (hormone) gradully declines after age 32. From that point on metabolism also declines, due to the testosterone hormone. With all the effects of weight gain, muscle loss (atrophy), and as aging continues the skin loses its elasticity.

-Females

When Females reach age 32 and older the progestrone (hormone) levels decline.

Progestrone is created within the uterus. In which the pituitary gland (in the back of the base of the brain) signals to produce the progestrone hormone.


The progestrone (hormone) gradully declines after age 32. From that point on metabolism also declines, due to the progestrone hormone. With all the effects of weight gain, muscle loss (atrophy), and as aging continues the skin loses its elasticity.

Brain Aging

Scientists are amassing a greater understanding of the long-term risk factors that adversely effect the brain in order to halt cognitive deterioration.

by Monika Guttman

In recent years, scientists have mapped the human genome, explored the surface of Mars and developed crops that produce their own pesticides.

By contrast, much about the human brain still remains a mystery. That is particularly true when it comes to understanding how the brain ages.

Part of the mystery is due to the fact that, until recently, people did not have the same lifespan as they do today-now an average 75 years, up from 47 years in 1900. This means there has been precious little time to study brain aging, says David Walsh, Ph.D., associate professor of psychology. He says, "Theoretically, this is a whole new world."

But research on how this three pound organ ages is speeding ahead-pushed by the fact that 10,000 U.S. baby boomers hit age 50 every day. This huge group, which will soon swell the ranks of senior citizens to previously unheard of proportions, wants to know what can be done to preserve brain function as long as possible.

After all, the brain is considered our most vital organ, responsible for everything from involuntary life support functions like heartbeats and breathing to the essence of personality and memory. It contains more than 100 billion cells including neurons-the specialized cells of the nervous system responsible for the transmission of electrical impulses to and from the central nervous system. Neurons can send signals to thousands of other cells at a rate of about 200 miles per hour. Just how these neurons work-a complicated system involving various chemicals (neurotransmitters) and electrical impulses-is only slowly coming to light.

Until recently, brain aging-and everything that entails, from the annoying inconveniences of age-related memory loss to more serious conditions like Alzheimer's and dementia-was equated with neuron failure. "I think historically the subject was thought to be very simple: that brain neurons were lost from birth onwards," explains Caleb Finch, Ph.D., the ARCO/William F. Kieschnick Chair in the Neurobiology of Aging and a professor of gerontology and biological sciences. "Now it is really clear that if you don't have a specific disease that causes loss of nerve cells, then most, if not all, of the neurons remain healthy until you die. That's a big change, and it has only come about in the last 10 years."

One reason for the change: improved technology like higher resolution magnetic resonance imaging (MRI) and positron emission tomography (PET) scans. These help scientists pinpoint the parts of the brain that function or fail as individuals age. The technology has also generated a wealth of information about the physical changes in the aging brain, including:

Brain weight and volume decrease. On average, the brain loses 5-10 percent of its weight between the ages of 20 and 90.

The grooves on the surface of the brain widen, while the swellings on the surface become smaller.

So-called "neurofibriallary tangles," decayed portions of the branch-like dentricles that extend from the neurons, increase.

"Senile plaques," or abnormally hard clusters of damaged or dying neurons, form.

Along with realizing these physical changes in the brain, one of the big surprises in recent years is data that suggests cognitive decline like age-related memory loss is not due to neuron loss, as previously thought. Instead, scientists now believe changes in function as we age have more to do with complex chemical interactions in the brain that occur over time.

For example, recent studies suggest plaques and tangles-long considered a cause of Alzheimer's-may not turn out to be the culprits after all. A study in the Journal of Neurophysiology examined the brains of elderly people who were fully functioning up to their death and found them to have a large number of plaques and tangles that looked exactly like Alzheimer's. But none of the subjects had displayed Alzheimer's symptoms.

Instead, new research suggests Alzheimer's may be connected to inflammatory processes associated with aging. Finch recently released findings of a new type of amyloid aggregates. Amyloid is a hard deposit that results from tissue degeneration, which forms in the presence of inflammatory proteins in the brain. The inflammatory proteins occur to a certain extent in all maturing adults, he notes. The soluble amyloid aggregates appear to form in the parts of the brain particularly affected by Alzheimer's (including the hippocampus, the area responsible for forming new memory). Once there, they appear to interfere with the brain's basic mechanism of long-term memory well before they reach a level high enough to kill brain cells, Finch says.

More evidence that brain aging is related to chemical changes in the brain comes from studies that suggest an age-related loss of dopamine, the brain chemical associated with pleasure and reward, slows metabolism in the regions of the brain related to cognition. Other research has explored conflicting data about the potential benefit of taking estrogen to reduce the risk of getting Alzheimer's disease for post-menopausal women.

Further complicating the picture is that these changes do not happen to everyone at the same pace, notes Helena Chui, M.D., the Raymond and Betty McCarron Chair in Neurology. Chui is also co-director of the McCarron Clinical Research and Education Center, headquartered at the USC-affiliated Rancho Los Amigos National Rehabilitation Center in Downey, Calif. "Certain brain injuries occur suddenly, like a stroke or head injury. Neurodegenerative processes such as Alzheimer's disease, on the other hand, occur gradually," says Chui. "Furthermore, different people develop plaques and tangles at different rates. At some threshold, symptoms become noticeable. At this point, we don't know all of the factors that determine these rates. Genetics, however, play an important role."

The genetic influence on the rate of brain aging is the focus of new research. Jeff Victoroff, M.D., associate professor of clinical neurology at the Keck School and director of neurobehavior at Rancho Los Amigos, suggests, "Genetic evolution may have even favored those who, once they hit the old age of 35, retained the capacity to teach and provide emotional support rather than those whose brains' limited resources were devoted to new learning." In evolution 100,000 years ago, he says, "It was probably rare for people to live past age 40 or 50, which means there was very little evolutionary selective pressure to make the brain work when we're 60 or 70 or 80. That's probably why all brains decline with aging."

What is most intriguing about the new findings in brain aging is that they indicate that the rate of change may be hastened or slowed by lifestyle factors. For instance, maintaining a lower weight might affect brain aging. As far back as the 1970s, Finch's experiments with mice found that those on restricted diets had lower rates of brain aging disease like Alzheimer's. Now, "We're trying to understand how cutting back the food intake in rodents slows the inflammatory process," Finch says. "I think one possibility is that it lowers blood glucose levels. Blood glucose is very reactive as a chemical and can cause damage to proteins." The opposite condition is diabetes-a condition with elevated blood sugar-and, Finch says, those with diabetes typically show more signs of brain aging than non-diabetic individuals.

Other lifestyle factors that may affect brain aging:

Education: Those who 'use it, don't lose it' as quickly, according to studies

that compare brain function in adults who attended college and those who did not. "We hesitate to say the brain is like a muscle. But using patterns of connectivity over and over and having those patterns prove useful to us in our life probably makes the synapses broader and the connections between neurons in these valuable and well-used systems stronger, "says Victoroff. One recent study showed that cognitive challenge actually created new neurons in the adult rodent brain, "which means that the old idea that mammals have all the neurons in the brain when born is probably wrong," says Victoroff. "We expect to discover which environmental stimuli such as physical and mental exercise, are most likely to turn on new neurons in the adult brain."

Exercise: Those who walk rapidly for as little as 45 minutes three times

a week significantly improve age-related declines in cognitive abilities, studies find.

Rest: There is new evidence that suggests a regular pattern of eight hours

of sleep per night helps protect against age-related chronic illnesses including memory loss.

Hypertension: Studies suggest hypertension speeds up normal brain

shrinkage and loss of mental abilities. Even those on antihypertensive medication have accelerated aging and shrinking of the brain.

Stress: When under stress, the human body produces a hormone called

cortisol. In small amounts, it can improve memory-which is what helps emotional events stay vividly in our minds. In larger amounts, however, it wears away at the neurons in the hippocampus.

Head trauma: It has long been known that boxers get punch drunk and

their brains exhibit changes that mimic Alzheimer's disease, only much earlier, notes Finch. A new series of studies show that former soccer players have declines in cognitive function in proportion to their use of their heads in propelling the ball. "Here is a sport that is becoming increasingly popular. Are kids setting themselves up for early mental deterioration every time there's a sharp blow to the head? That's something that needs to be investigated," Finch says.

Does this mean taking these specific steps will keep your brain in top condition? Although they acknowledge that genes play a large role in predetermining your brain's aging, researchers are beginning to agree that taking care of your health might help your long term brain function. This topic is explored in Victoroff's new book "Saving Your Brain," which Bantam will publish in spring 2002. In the book, he suggests steps like strict control of blood pressure, blood sugar and cholesterol, diet, the use of certain vitamins, physical exercise and mental exercise to help keep the brain functioning at its peak. "These are probably things 15 year olds should be doing, because the effect on the brain is cumulative," he says. "It certainly helps if someone in their 40s, 50s or even 70s starts to take the right steps, but the younger you are, the larger an impact it will have on delaying brain aging."

Finch, Chui, Victoroff and others are optimistic that the future will bring better understanding-and treatment-of brain aging and its associated symptoms. Drugs now in preclinical or Phase I human trials to treat Alzheimer's, says Chui, may decrease the levels of amyloids in the brain. Other experiments now underway suggest that deterioration in critical brain networks may be restored by gene therapy-transplanting brain cells genetically programmed to release a protein called nerve growth factor. The research focuses on a particular set of brain cells deep in the brain known as cholinergic neurons, which are shown to deteriorate rapidly in those with Alzheimer's disease.

"Studies show that the human brain is built to go for an amazing length of time," says Finch. Ten years from now, "we'll have a greater understanding of the long-term risk factors that have adverse effects on the brain. We'll know which people are more at risk earlier in their lives because of their genes. Knowing more about genes and the environment is not likely to yield a magic bullet, but each decade will nibble away at the adverse aspects of brain aging."

Adds Victoroff, "Although we need to know a great deal more, we are long overdue in recognizing a simple fact: Cognitive loss is largely preventable. This is a watershed point in our understanding of dementia. Once the news gets out, it will percolate into the public's consciousness and begin to influence behavior."

Eyes Aging

Our eyes age over our life span. Due to hormone levels and blood glucose levels rising up and going down.

The pancreas produces insulin (blood glucose) in which has a adverse effect on the human eyes on aging. In which controlling (blood glucose) levels is to keep your blood sugar as stable as possible throughout the day.

Joints Aging

Osteoporosis — the "silent disease" Although the number-one “silent disease” is high blood pressure, osteoporosis is an important silent disease affecting millions of Americans, especially older ones. Osteoporosis is the gradual loss of calcium and bone that occurs over time beginning around age 40, greatly increasing in women at or around the time of menopause. By the time people reach their 70s, the rate of bone thinning in men equals women. Bone is living tissue, and like most tissue, it dies and is replaced. However, as people age, tissue dies at a faster rate and does not have time to be fully replaced. As a result, bones become less dense and less strong each year. This bone loss leads to easy fractures, often alerting people for the first time of their osteoporosis. People at greatest risk of osteoporosis are those who:

-have a family history of the disease

-have not gotten enough calcium throughout their lives

-had an early menopause

-had surgery to remove their ovaries

-had extended bed rest

-used certain medicines for a long time

-have small body frames

Approximately 10 million people have osteoporosis, and 80 percent of these people are women. Therefore, women more commonly suffer fractured hips, which may require hospitalization and surgery.

To test for this “silent disease,” ask your doctor for a bone density examination. This examination is performed by dual-energy x-ray absorptiometry, commonly called DEXA-scan, which is a painless and quick diagnostic study. DEXA-scan can tell you and your physician if you have osteoporosis or osteopenia — an early form of osteoporosis.

Exercise has been proven to prevent bone loss. Everyone who reads this column knows that weight bearing exercise at least three times a week is something I recommend for many diseases, and it is important in preventing or treating osteoporosis as well. Exercise can range from walking to much more strenuous forms of exercise including running or tennis. The important thing is to exercise regularly.

Exercising regularly will keep the bones strong. The bones are living and have 300 million cells in them that are constantly replaced 300 million times a day. The material in bones are 2-3 times strong due the bones being hard and calcified, and there is no other material like it on the planet.

Medicine can be prescribed for the prevention and treatment of osteoporosis. Ask your doctor if medicine is right for you. If bone density is restored or further loss prevented, the risk for bone fractures is reduced.

Osteoarthritis

Unlike osteoporosis, people who develop osteoarthritis know they have it because they have pain in their joints. The main three of approximately 100 forms of arthritis include rheumatoid, osteoarthritis and gout.

Osteoarthritis commonly leads to joint replacement surgery and is the most common type of arthritis in older people. It mostly affects the cartilage in and around the joints and usually affects one or more of the hands or large weight-bearing joints including knees and hips. Cartilage, which cushions the ends of bones within joints, doesn’t provide sufficient cushioning when it is worn down or calcified. In severe cases, the bones in the joint rub directly against each other.

Symptoms of osteoarthritis range from stiffness and mild pain that comes and goes to severe joint pain. Before age 45, it is more common in men, but by age 65, more than half of the population has x-ray evidence of osteoarthritis in at least one joint. Simple joint use is the most common cause, but over-use or injury may also cause osteoarthritis.

Treatment of osteoarthritis is rest, gradual exercise, a well-balanced diet, and instruction on the right way to use joints. Nonsteroidal anti-inflammatory drugs (NSAIDS) such as ibuprofen are very helpful in controlling osteoarthritis, but they don’t cure it. Any over-the-counter or prescription drug should be discussed with your doctor since they all carry potentially serious side effects.

Glucosamine Chondroitin is a supplement that you may go and get at your local store. Glucosamine Chondroitin works wonders for people who already have Osteoarthritis.

Glucosamine Chondroitin is shown to work with patients that have Rheumatoid Arthritis to help reduce the pain and inflammation in the joints.

I myself have seen two people. One with Arthritis in the knee and another person with advanced Rheumatoid Arthritis and studies have shown for the supplement to work well.

To prevent Osteoarthritis drink plenty of water to keep the joints lubricated so that the water prevents any damage. For people who do not have Osteoarthritis.

Kidney Failure

-What are the kidneys?

-What causes kidney failure?

-What are the symptoms of kidney failure?

-How is kidney failure diagnosed?

-What is the treatment for kidney failure?

-Diet

-Medications

-Dialysis

-Hemodialysis

-Peritoneal dialysis

What are the kidneys?

The kidneys play key roles in body function, not only by filtering the blood and getting rid of waste products, but also by balancing levels of electrolytes in the body, controlling blood pressure, and stimulating the production of red blood cells.

The kidneys are located in the abdomen toward the back, normally one of each side of the spine. They get their blood supply through the renal arteries directly from the aorta and send blood back to the heart via the renal veins to the vena cava. (The term "renal" is derived from the Latin name for kidney.)

The kidneys have the ability to monitor the amount of body fluid, the concentrations of electrolytes like sodium and potassium, and the acid-base balance of the body. They filter waste products of body metabolism, like urea from protein metabolism and uric acid from DNA breakdown. Two waste products in the blood can be measured: blood urea nitrogen (BUN) and creatinine (Cr).

When blood flows to the kidney, sensors within the kidney decide how much water to excrete as urine, along with what concentration of electrolytes. For example, if a person is dehydrated from exercise or from an illness, the kidneys will hold onto as much water as possible and the urine becomes very concentrated. When adequate water is present in the body, the urine is much more dilute, and the urine becomes clear. This system is controlled by renin, a hormone produced in the kidney that is part of the fluid and blood pressure regulation systems of the body.

Kidneys are also the source of erythropoietin in the body, a hormone that stimulates the bone marrow to make red blood cells. Special cells in the kidney monitor the oxygen concentration in blood. If oxygen levels fall, erythropoietin levels rise and the body starts to manufacture more red blood cells.

After the kidneys filter blood, the urine is excreted through the ureter, a thin tube that connects it to the bladder. It is then stored in the bladder awaiting urination, when the bladder sends the urine out of the body through the urethra.

What causes kidney failure?

Kidney failure can occur from an acute situation or from chronic problems.

In acute renal failure, kidney function is lost rapidly and can occur from a variety of insults to the body. The list of causes is often categorized based on where the injury has occurred.

Prerenal causes (pre=before + renal=kidney) causes are due to decreased blood supply to the kidney. Examples of prerenal causes are:

Hypovolemia (low blood volume) due to blood loss

Dehydration from loss of body fluid (vomiting, diarrhea, sweating, fever )

Poor intake of fluids

Medication, for example, diuretics ("water pills") may cause excessive water loss.

Loss of blood supply to the kidney due to obstruction of the renal artery or vein.

Renal causes (damage directly to the kidney itself) include:

Sepsis: The body's immune system is overwhelmed from infection and causes inflammation and shutdown of the kidneys. This usually does not occur with urinary tract infections.

Medications: Some medications are toxic to the kidney, including nonsteroidal anti-inflammatory drugs like ibuprofen and naproxen. Others are antibiotics like aminoglycosides [gentamicin (Garamycin), tobramycin], lithium (Eskalith, Lithobid), iodine-containing medications such as those injected for radiology dye studies.

Rhabdomyolysis: This is a situation in which there is significant muscle breakdown in the body, and the degeneration products of muscle fibers clog the filtering system of the kidneys. Often occurring because of trauma and crush injuries, it can also be caused by some medications used to treat high cholesterol.

Multiple Myeloma

Acute glomerulonephritis or inflammation of the glomeruli, the filtering system of the kidneys. Many diseases can cause this inflammation including systemic lupus erythematosus, Wegener's granulomatosis, and Goodpasture syndrome.

Post renal causes (post=after + renal= kidney) are due to factors that affect outflow of the urine:

Obstruction of the bladder or the ureters can cause back pressure when there is no place for the urine to go as the kidneys continue to work. When the pressure increases enough, the kidneys shut down.

Prostatic hypertrophy or prostate cancer may block the urethra and prevents the bladder from emptying.

Tumors in the abdomen that surround and obstruct the ureters.

Kidney stones

Chronic renal failure develops over months and years. The most common causes of chronic renal failure are related to:

-Poorly controlled diabetes

-Poorly controlled high blood pressure

-Chronic glomerulonephritis

-Less common causes:

-Polycystic Kidney Disease

-Reflux nephropathy

-Kidney stones

-Prostate disease

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