Young, healthy muscle (left column) appears pink and red. In contrast, the old muscle is marked by scarring and inflammation, as evidenced by the yellow and blue areas. This difference between old and young tissue occurs both in the muscle's normal state and after two weeks of immobilization in a cast. Exercise after cast removal did not significantly improve old muscle regeneration; scarring and inflammation persisted, or worsened in many cases. Credit: Morgan E. Carlson and Irina M. Conboy, UC Berkeley
Clock Turned Back on Aging Muscles, Researchers Claim
By Robert Roy Britt, Editorial Director
Scientists have found and manipulated body chemistry linked to the aging of muscles and were able to turn back the clock on old human muscle, restoring its ability to repair and rebuild itself, they said today.
The study involved a small number of participants, however. And the news is not all rosy.
Importantly, the research also found evidence that aging muscles need to be kept in shape, because long periods of atrophy are more challenging to overcome. Older muscles do not respond as well to sudden bouts of exercise, the scientists discovered. And rather than building muscle, an older person can generate scar tissue upon, say, lifting weights after long periods of inactivity.
The findings are detailed today in the European journal EMBO Molecular Medicine.
"Our study shows that the ability of old human muscle to be maintained and repaired by muscle stem cells can be restored to youthful vigor given the right mix of biochemical signals," said study leader Irina Conboy of the University of California, Berkeley. "This provides promising new targets for forestalling the debilitating muscle atrophy that accompanies aging, and perhaps other tissue degenerative disorders as well."
More research would be needed before any anti-aging products might result from the work, however.
Scientists know that muscles deteriorate rapidly in old age. Mechanisms that prevent muscle breakdown work less effectively in people over the age of 65, a study earlier this month found. Other research has shown that neurons have to yell louder to kick aging muscles into gear.
Yet much about how and why muscles respond to exercise, and atrophy without it, remains unknown.
Previous research in animal models led by Conboy revealed that the ability of adult stem cells to do their job of repairing and replacing damaged tissue is governed by the molecular signals they get from surrounding muscle tissue, and that those signals change with age in ways that thwart tissue repair. But the animal studies also showed that the regenerative function in old stem cells can be revived.
Meanwhile, there is no fountain of youth for aging muscles. The best advice for now: Eat well and exercise regularly throughout life.
Human muscle atrophy
In the new study, a team of researchers compared samples of muscle tissue from nearly 30 healthy men. The young group ranged from age 21 to 24 and averaged 22.6 years old, while the older group averaged 71.3 years old, ranging from 68 to 74.
Muscle biopsies were taken from one quadriceps (upper leg muscle) of each test subject, who then had that leg immobilized in a cast for two weeks to simulate muscle atrophy. After the casts were removed, the men lifted weights to regain muscle mass. More muscle tissue samples were taken.
Analysis showed that before the legs were immobilized, the adult stem cells responsible for muscle repair and regeneration were only half as numerous in the old muscle as they were in young tissue. (Muscle stem cells produce other muscle cells.) The disparity increased during exercise, with younger tissue having four times more regenerative cells compared with the old muscle.
Muscles of the older participants showed signs of inflammation and scar tissue formation during immobility and again four weeks after the cast was removed.
"Two weeks of immobilization only mildly affected young muscle, in terms of tissue maintenance and functionality, whereas old muscle began to atrophy and manifest signs of rapid tissue deterioration," said Morgan Carlson, another UC Berkeley researcher and the study's lead author.
"The old muscle also didn't recover as well with exercise," Carlson said. "This emphasizes the importance of older populations staying active because the evidence is that for their muscle, long periods of disuse may irrevocably worsen the stem cells' regenerative environment."
The researchers warned that in the elderly, rigorous exercise after immobility can cause replacement of functional muscle by scarring and inflammation.
"It's like a Catch-22," Conboy said.
Previous studies have shown that adult muscle stem cells have a receptor called Notch, which triggers growth when activated. Those stem cells also have a receptor for the protein TGF-beta that, when excessively activated, sets off a chain reaction that ultimately inhibits a cell's ability to divide. In aging mice, the decline of Notch and increased levels of TGF-beta ultimately block the stem cells' ability to rebuild muscle.
The new study found the same process at work in humans. But it also revealed that an enzyme called mitogen-activated protein kinase (MAPK) regulates Notch activity.
In old muscle, MAPK levels are low, so the Notch pathway is not activated and the stem cells no longer perform their muscle regeneration jobs properly, the researchers said.
In the lab, the researchers cultured old human muscle and forced the activation of MAPK. The regenerative ability of the old muscle was significantly enhanced, they report.
"In practical terms, we now know that to enhance regeneration of old human muscle and restore tissue health, we can either target the MAPK or the Notch pathways," Conboy said. "The ultimate goal, of course, is to move this research toward clinical trials."
The research was supported by the National Institutes of Health, the California Institute of Regenerative Medicine, the Danish Medical Research Council and the Glenn Foundation for Medical Research.
Wednesday, September 30, 2009
Sunday, September 27, 2009
There are many things you can rationalize. [rational lies] Smoking is not one of them. It is a filthy, killer that not only kills the practitioner, but those around them. I have always been anti smoking. Almost all of my relatives smoked during the WW2 years, then quit. These were not stressed out accountants, but mill workers and coal miners. Many of my Uncles started smoking at age 11 in fact. They all quit. As I've aged I have become more tolerant of behavior which I would think is a sign of maturity. I have no tolerance for smoking. None. I saw someone associated with a cancer benefit smoking recently. I don't understand that behavior and trying to will only build frustration with such stupidity. Here are some government facts on smoking and the diseases it causes.
* Cancer is the second leading cause of death and was among the first diseases causually linked to smoking.
* Smoking causes about 90% of lung cancer deaths in men and almost 80% of lung cancer deaths in women. The risk of dying from lung cancer is more than 23 times higher among men who smoke cigarettes, and about 13 times higher among women who smoke cigarettes compared with never smokers.
* Smoking causes cancers of the bladder, oral cavity, pharynx, larynx (voice box), esophagus, cervix, kidney, lung, pancreas, and stomach, and causes acute myeloid leukemia.
* Rates of cancers related to cigarette smoking vary widely among members of racial/ethnic groups, but are generally highest in African-American men.
Cardiovascular Disease (Heart and Circulatory System)
* Smoking causes coronary heart disease, the leading cause of death in the United States. Cigarette smokers are 2–4 times more likely to develop coronary heart disease than nonsmokers.
* Cigarette smoking approximately doubles a person's risk for stroke.
* Cigarette smoking causes reduced circulation by narrowing the blood vessels (arteries). Smokers are more than 10 times as likely as nonsmokers to develop peripheral vascular disease.
* Smoking causes abdominal aortic aneurysm.
Respiratory Disease and Other Effects
* Cigarette smoking is associated with a tenfold increase in the risk of dying from chronic obstructive lung disease. About 90% of all deaths from chronic obstructive lung diseases are attributable to cigarette smoking.
* Cigarette smoking has many adverse reproductive and early childhood effects, including an increased risk for infertility, preterm delivery, stillbirth, low birth weight, and sudden infant death syndrome (SIDS).
* Postmenopausal women who smoke have lower bone density than women who never smoked. Women who smoke have an increased risk for hip fracture than non smokers.
By the way, adding cigarette smoking to alcohol is not additive in its destructive, killing, power, it's multiplicative. You really want to die.
Here is a link to the Mayo Clinic's article on great strategies to stop smoking. LINK
Let's also use some visual tools. Here is what your lungs look like when you smoke.
Here is what your lips look like from smoking.
Sometimes appealing to the ego is more effective than appealing to logic.
Monday, September 21, 2009
In the photo above you see what happens when you set your mind on something and don't let it stop you. Bill Superfoot Wallace, American, National, Grand National Karate Champion. Undefeated PKA Middleweight Champion. Actor and stuntman. He is 64 years old, has had a double hip replacement, and he still keeps on kicking and moving. He ignores the number, and realizes that 90% of life is showing up. He is at a fighting workshop and teaching the young fighters what a battle hardened veteran can still do. He doesn't use a cane or wheel chair or have a big gut over his belt. Bill is a lifelong athlete and son of an athletic coach and has no time for getting old. Think of Superfoot when you do your workout tomorrow!
In the photo above, Jon Hinds, owner of the Monkey Bar Gym in Madison, Wisconsin, is teaching his 79 year old Mother how to do a handstand! She didn't start here, but began over months with a slow progression to this point. Nothing is impossible if you believe. Nothing.
Sunday, September 6, 2009
As a youth, I heard the term "beer belly" quite a bit. In Pittsburgh and the surrounding areas, the concentration of "beer gardens" made the "Ripley's Believe It Or Not" list. There was adequate anecdotal evidence of this occurrence in my youth for me to make some idiotic assumptions that this phenomena actually existed. That by consuming liquid calories in the form of a central nervous system depressant would actually stretch the abdominal wall and make a large, hardened, abdomen seemed to be a reasonable concept. Men would actually be proud of their distended thorax and tell you that "it isn't flab". I was actually challenged as a young child to punch a guy in the gut. It hurt my hand and wrist. I viewed it almost as a sign of robustness and strength. It actually took a health class and a reasonable teacher to explain what was going on. Not medical journals or Pub Med studies, although those added more clarity in later years. My teacher, Mr. Zona, pointed out that we stored fat in different areas. The most common were underneath the skin ( subcutaneous ), and in the abdominal cavity ( visceral ). He told us that excess fat was a health risk. He did not elaborate since it was sixth grade and we have FAR more data now about body fat.
In health news as seen online, in print, and on TV, we hear about the pear and apple shapes. We have been told that the pear shape, is unhealthy, but not as high risk as the apple shape. Storing excess fat in the subcutaneous region of the belly, buttocks, and thighs, while unsightly, is a safer state. The apple shape represents fat stored around the organs. The fat has a rich blood supply and increased the risk of high blood pressure, heart disease, and associated illnesses dramatically. Below is an example of the difference in body shape.
Remember, those with subcutaneous fat are not off the hook. Excessive body fat still represents risk, even with good blood results. Those pounds are adding stress to your knees, feet, and back. This will cause deterioration of the connective tissue which will reduce mobility and minimize the ability to burn calories. Remember, immobility is death. Mobility is youth and life.
Some individuals think liposuction or abdominoplasty is the answer. The photo below shows that while the fat apron on this morbidly obese individual has been reduced,... the visceral fat, (white area in the body scan) is exactly the same even though the subcutaneous areas have been sucked out or cut off.
Liposuction is not a method of weight reduction. The body can recreate new fat cells when you over eat and your existing fat cells reach a size limit. It's very efficient at storing energy. Cutting off rolls and fat aprons is restricted to those who have undergone massive weight loss and have excessive skin. This excess may limit mobility and represent a higher risk of skin infections.
The bad part is, the "beer belly", is simply visceral fat. It increases your chances of checking out. The good part is that it's the first place the body uses for energy in a negative calorie balance. Eat less food than you need, burn more calories than you take in, and your visceral fat will reduce in size. Your mobility will increase and you can pursue more vigorous activity to get in even better shape. It's really that simple. It's your responsibility to take charge of what is put in your mouth.