Post by David Feder on Jul 20, 2008 13:07:04 GMT -5
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Why does not atrophy immobility the bears?
Studying the hibernation of bears, a group of researchers hopes to find the key to prevent muscular atrophy
Monica L. Ferrado
When a person needs to stay in bed for a long time, if the muscle atrophy. Behind this process is a complicated molecular mechanism that scientists are beginning to unravel. A team of University of Barcelona seeking a way to the braking process. For this, turned to the nature. They want to know how the bears, despite remaining buildings during the long period of hibernation, retain their muscles intact.
During the cold months, between the second half of November and March, the brown bear in Pyrenees retires to his regards to hibernate. There remains immobile, sleeping shrunk, with the muzzle near the tail. He is able to withstand such extreme conditions, without food or water, because your metabolism is adjusting. His body temperature drops four or five degrees, and low heart rate to around 10 beats per minute. Thus, the bear can reduce their energy consumption by up to three quarters of normal. After staying awake for four months, when the weather improves, he leaves his hideout, hungry, ready to resume activity and achieve food.
What would happen if people and the bears, were sleeping at home throughout the winter, without moving any muscle to not spend energy? If someone remained immobile for so long, lose muscle mass to the point of having more or less serious problems of mobility that demandariam some type of rehabilitation. Studying the bears, a group of researchers at the University of Barcelona expects to find the key to prevent muscle atrophy in people who, by padecerem any illness, are obliged to stay in bed for long periods of time.
What happens in our bodies when we move so that the muscles are deteriorating? In humans, destruction of muscle tissue is a sign of stress related to certain metabolic diseases such as cancer and AIDS, and long periods of malnutrition, disease or detention by microgravity, in the case of astronauts. It also happens in healthy people who live a sedentary life, even that good health and exercise could regain lost muscle mass.
Loss of muscle mass
Because of the lack of movement, a process known as proteolysis is activated. "We know that metabolic changes occur that activate the molecular process that leads to loss of muscle mass, the proteolysis.
This is a mechanism which means that if the break myofibrillar protein, found in muscle fibers and responsible for preserving the muscle, its strength and contraction, "says Josep Maria Ariglés, researcher of the Group of Biochemistry and Molecular Biology at the University of Cancer of Barcelona. The breakdown of these proteins affect one another, the ubiquitin, which intervenes in the signs that lead to cell destruction, although the researchers need further investigation to know the process further. "Compared to what we know about the synthesis of protein, yet we know very little about the degradation processes, and are regulated mainly as, "explains Argilés.
Scientists also believe that several other factors can add to that process of loss of muscle mass. "In a situation pathological, as a cancer, the molecules produced by the tumor or the patient's immune system can also contribute to the process," explains Argilés. The cachexia (medical term that means the muscular atrophy linked to other diseases) affects 40% of individuals with malignant tumors. In fact, 30% of cancer deaths are due to a cardiac or respiratory failure related muscle loss.
In the case of the elderly, this process of muscle atrophy is known by another name, sarcopenia. "In the elderly the process is faster and some studies indicate that could be related to hormonal changes, such as reducing the concentration of testosterone or growth hormone," explains Argilés. The loss of muscle mass starts from 35 years.
But what the bears have, and not humans, so that does not lose its muscle despite not move for so long? The key is in their blood plasma.
During the months of hibernation, the bears do not lose muscle mass, just fat. "That leads us to believe that the plasma of bears in hibernation contains a factor regulating degradation of proteins that block this process in the body," explains Argilés.
The researcher managed to demonstrate this effect in experiments with rats. For this, isolated in glass muscle cells of rodents, which put in contact with the plasma of bears in hibernation, taken from different species of bears (brown bear in Pyrenees and polar bear), with some samples provided by the zoo in Barcelona. "We make the plasma blocked the process of muscle breakdown by 40%. This potential inhibitor of plasma of the bear could regulate the proteolysis in a natural way, and this could have a therapeutic use," he explains.
Yet it remains hard to get these discoveries can be turned into medicines. Researchers are working to identify and isolate the component of the plasma that can bear the braking molecular mechanism. When can the injetarão in laboratory animals.
According Argilés, if all goes well, tests on humans could begin in the coming year in patients suffering from stomach cancer. His team also conducted studies in healthy people and found that the loss of muscle mass is already significant after 15 days of immobility in bed.
Visit the El Pais
Why does not atrophy immobility the bears?
Studying the hibernation of bears, a group of researchers hopes to find the key to prevent muscular atrophy
Monica L. Ferrado
When a person needs to stay in bed for a long time, if the muscle atrophy. Behind this process is a complicated molecular mechanism that scientists are beginning to unravel. A team of University of Barcelona seeking a way to the braking process. For this, turned to the nature. They want to know how the bears, despite remaining buildings during the long period of hibernation, retain their muscles intact.
During the cold months, between the second half of November and March, the brown bear in Pyrenees retires to his regards to hibernate. There remains immobile, sleeping shrunk, with the muzzle near the tail. He is able to withstand such extreme conditions, without food or water, because your metabolism is adjusting. His body temperature drops four or five degrees, and low heart rate to around 10 beats per minute. Thus, the bear can reduce their energy consumption by up to three quarters of normal. After staying awake for four months, when the weather improves, he leaves his hideout, hungry, ready to resume activity and achieve food.
What would happen if people and the bears, were sleeping at home throughout the winter, without moving any muscle to not spend energy? If someone remained immobile for so long, lose muscle mass to the point of having more or less serious problems of mobility that demandariam some type of rehabilitation. Studying the bears, a group of researchers at the University of Barcelona expects to find the key to prevent muscle atrophy in people who, by padecerem any illness, are obliged to stay in bed for long periods of time.
What happens in our bodies when we move so that the muscles are deteriorating? In humans, destruction of muscle tissue is a sign of stress related to certain metabolic diseases such as cancer and AIDS, and long periods of malnutrition, disease or detention by microgravity, in the case of astronauts. It also happens in healthy people who live a sedentary life, even that good health and exercise could regain lost muscle mass.
Loss of muscle mass
Because of the lack of movement, a process known as proteolysis is activated. "We know that metabolic changes occur that activate the molecular process that leads to loss of muscle mass, the proteolysis.
This is a mechanism which means that if the break myofibrillar protein, found in muscle fibers and responsible for preserving the muscle, its strength and contraction, "says Josep Maria Ariglés, researcher of the Group of Biochemistry and Molecular Biology at the University of Cancer of Barcelona. The breakdown of these proteins affect one another, the ubiquitin, which intervenes in the signs that lead to cell destruction, although the researchers need further investigation to know the process further. "Compared to what we know about the synthesis of protein, yet we know very little about the degradation processes, and are regulated mainly as, "explains Argilés.
Scientists also believe that several other factors can add to that process of loss of muscle mass. "In a situation pathological, as a cancer, the molecules produced by the tumor or the patient's immune system can also contribute to the process," explains Argilés. The cachexia (medical term that means the muscular atrophy linked to other diseases) affects 40% of individuals with malignant tumors. In fact, 30% of cancer deaths are due to a cardiac or respiratory failure related muscle loss.
In the case of the elderly, this process of muscle atrophy is known by another name, sarcopenia. "In the elderly the process is faster and some studies indicate that could be related to hormonal changes, such as reducing the concentration of testosterone or growth hormone," explains Argilés. The loss of muscle mass starts from 35 years.
But what the bears have, and not humans, so that does not lose its muscle despite not move for so long? The key is in their blood plasma.
During the months of hibernation, the bears do not lose muscle mass, just fat. "That leads us to believe that the plasma of bears in hibernation contains a factor regulating degradation of proteins that block this process in the body," explains Argilés.
The researcher managed to demonstrate this effect in experiments with rats. For this, isolated in glass muscle cells of rodents, which put in contact with the plasma of bears in hibernation, taken from different species of bears (brown bear in Pyrenees and polar bear), with some samples provided by the zoo in Barcelona. "We make the plasma blocked the process of muscle breakdown by 40%. This potential inhibitor of plasma of the bear could regulate the proteolysis in a natural way, and this could have a therapeutic use," he explains.
Yet it remains hard to get these discoveries can be turned into medicines. Researchers are working to identify and isolate the component of the plasma that can bear the braking molecular mechanism. When can the injetarão in laboratory animals.
According Argilés, if all goes well, tests on humans could begin in the coming year in patients suffering from stomach cancer. His team also conducted studies in healthy people and found that the loss of muscle mass is already significant after 15 days of immobility in bed.
Visit the El Pais