Posted on 09/26/2006 6:28:56 PM PDT by Pharmboy
Too much testosterone can kill brain cells, researchers said on Tuesday in a finding that may help explain why steroid abuse can cause behavior changes like aggressiveness and suicidal tendencies.
Tests on brain cells in lab dishes showed that while a little of the male hormone is good, too much of it causes cells to self-destruct in a process similar to that seen in brain illnesses such as Alzheimer's.
"Too little testosterone is bad, too much is bad but the right amount is perfect," said Barbara Ehrlich of Yale University in Connecticut, who led the study.
Testosterone is key to the development, differentiation and growth of cells and is produced by both men and women, although men produce about 20 times more of the hormone.
It can also be abused, and recent scandals have involved athletes who use the hormone, or steroids that turn into testosterone in the body, for an unfair advantage.
"Other people have shown that high levels of steroid can cause behavioral changes," Ehrlich said in a telephone interview.
"We can show that when you have high levels of steroids, you have high testosterone and that can destroy the nerve cells. We know that when you lose brain cells you lose function."
Ehrlich's team tried the same thing with the "female" hormone estrogen, just to be fair.
"We were surprised, but it actually looks like estrogen is neuroprotective. If anything, there is less cell death in the presence of estrogen," she said.
Writing in the Journal of Biological Chemistry, Ehrlich and colleagues said their findings meant people should think twice about supplementing with testosterone, even if it does build muscle mass and aid recovery after exercise.
"These effects of testosterone on neurons will have long term effects on brain function," they wrote.
"Next time a muscle-bound guy in a sports car cuts you off on the highway, don't get mad -- just take a deep breath and realize that it might not be his fault," Ehrlich said in a statement.
The cells die via a process called apoptosis, also known as cell suicide or programmed cell death.
"Apoptosis is an important thing for the brain -- the brain needs to weed out some of the cells. But when it happens too frequently, you lose too many cells and causes problems."
A similar process is seen in Alzheimer's disease, the most common cause of dementia in the United States, affecting an estimated 4.5 million Americans, and Huntington's disease, another fatal brain illness.
"Our results suggest that the responses to elevated testosterone can be compared with these pathophysiological conditions," the researchers wrote.
dumas resirchers,, im beeting there buts.
Ha! No--THAT one is too busy having plastic surgery to do any research...
Well, gollllly....ain't she real smart.
Well.....wouldn't this mean more men than women would die of Alzheimers.....I don't know if that's true or not....
They're trying to back up feminist theory with data...not gonna work. Check out the Nobel Prize list...
Yikes....she looks likes she's taking too much testosterone herself!
Huh?
Females are superior to males by design. Is that it, in a nutshell?
ELAINE Look at my fish... JERRY EXAMINES IT... ELAINE (CONT'D) Is he... JERRY No, but he's not looking good...
ELAINE TURNS TO TWO HUGE BODY BUILDERS IN WORKOUT WEAR...
ELAINE (DESPERATE) Please, we can't find our car. Please drive us around the parking lot to find our car. My fish are dying.
MAN #2 Can't do it.
ELAINE I can see not caring what happens to us, we're human. But what about the fish? The fish?
MAN #3 Sorry. THEY KEEP WALKING.
ELAINE That's right, go. Go home to your dumbbells. Work on your pecs. I'm really impressed.
He, he ...
Age-specific incidence rates of Alzheimer's disease: the Baltimore Longitudinal Study of Aging.
Kawas C, Gray S, Brookmeyer R, Fozard J, Zonderman A.
Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA.
OBJECTIVE: To estimate age-specific incidence rates of AD in the Baltimore Longitudinal Study of Aging (BLSA). BACKGROUND: The BLSA is a volunteer cohort of normal subjects followed longitudinally with biennial evaluations at the Gerontology Research Center of the National Institute on Aging. METHODS: Subjects are 1236 participants (802 men, 434 women) in the BLSA with longitudinal follow-up between January 1985 and May 1998. The average length of follow-up was 7.5 years, with participants evaluated every 2 years by physical, neurologic, and neuropsychological examinations. Using Diagnostic and Statistical Manual of Mental Disorders, 3rd ed., revised and National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria, the authors diagnosed dementia and AD. RESULTS: The authors diagnosed 155 cases of dementia, of which 114 (74%) were AD. Incidence rates of AD increased with age from an estimated 0.08% per year (95% CI 0.00 to 0.43) in the 60 to 65 age group to an estimated 6.48% per year (95% CI 5.01 to 8.38) in the 85+ age group for men and women combined. The doubling time of incidence rates was estimated to be approximately 4.4 years and the median time of conversion from mild cognitive impairment to diagnosis of AD was estimated to be 4.4 years. There was a trend for women to have higher incidence rates than men and for fewer years of education to be associated with higher incidence rates; however, these effects were not significant. CONCLUSION: Incidence rates for AD in the BLSA are consistent with published rates in other studies. The longitudinally followed subjects of the BLSA offer a unique opportunity to prospectively investigate the antecedents of AD.
Hey cutie...I'm losing cells by the minute...wantta hang out??
( :-D
lol
George: What is Tungsten or Wolfram?
Alex Trebek: We were looking for 'What is Tungsten, or Wolfram'.
Jerry: Is this a repeat?
George: No, no, no. Just lately, I've been thinking a lot clearer. Like this afternoon, (To television) what is chicken Kiev, (Back to Jerry) I really enjoyed watching a documentary with Louise.
Jerry: Louise! That's what's doin' it. You're no longer pre-occupied with sex, so your mind is able to focus.
George: You think?
Jerry: Yeah. I mean, let's say this is your brain. (Holds lettuce head) Okay, from what I know about you, your brain consists of two parts: the intellect, represented here (Pulls off tiny piece of lettuce), and the part obsessed with sex. (Shows large piece) Now granted, you have extracted an astonishing amount from this little scrap. But with no-sex-Louise, this previously useless lump, is now functioning for the first time in its existence. (Eats tiny piece of lettuce)
George: Oh my God. I just remembered where I left my retainer in second grade. I'll see ya. (He throws finished Rubik's cube to Jerry and he exits. Kramer enters)
YOU'RE DOOMED...DOOMED!!!
Those Yale folks are right smart aren't they. So let me get this straight - what you are saying is that the right amount of testosterone is good.
I guess that must be the Goldie Locks hypothesis.
He, he he he he he .... (coy)
This true for almost every substance on earth
Agenda driven science.
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