衰老,抗衰老药物 z-bo 2020-09-21 364

　　Aging is an irreversible law of nature. This is a common idea, but a team of American scientists believes that aging is a disease and is looking for drugs that can cure it. They also submitted an application to the U.S. Food and Drug Administration, suggesting that anti-aging drugs be listed as a new drug category. The organization recently approved the world's first anti-aging drug, metformin, for clinical trials. .. Successful experiments are expected to extend human life and delay the onset of senile diseases. In other words, human beings have taken a new step towards the goal of "immortality".

　　A, anti-aging drugs in soil

　　Aging is a mysterious process that can cause obvious changes, such as hair albinism and wrinkles, but most people now know the changes in human cell levels. No. Scientists believe that aging is the accumulation of tissue damage within cells. Cells continuously receive signals from the human body and the surrounding environment, thereby accelerating cell aging, such as oxidative damage and inflammation. This process is a very complicated maze, which may confuse researchers. Aging is the biggest risk factor for diseases, and scientists hope to find a "master switch" to control aging. In theory, anti-aging drugs can control this "conversion", not only can delay or prevent aging, but also many diseases related to aging. So far, they have used various means to try to find ways to extend human life.

　　In August of this year, a research team composed of American doctors and scientists submitted an application to the U.S. Food and Drug Administration, proposing to include anti-aging drugs as a new drug category. This means that people see aging as a disease, not a natural law. In fact, many scientists believe that the ability to produce anti-aging drugs is no longer a problem. The question is when will it start selling.

　　Scientists discovered anti-aging drugs more than 30 years ago. This is rapamycin. It was found in soil samples on the island of Rapa Nui in Polynesia. It may be the most effective anti-aging drug ever. drug. Rapamycin is currently used as an immunosuppressant to reduce rejection during kidney transplantation. At the same time, it is also used to treat certain cancers due to its ability to inhibit cell growth.

　　As early as 2009, researchers conducted observational studies on drugs: feeding rapamycin to mice equivalent to 60 years old can extend the lifespan of female and male mice by 38%. The life span has been extended. The service life is extended by 28%. Tests have also proved that the drug can extend the lifespan of yeast, worms and small worms. The secret of life-prolonging rapamycin is that it can block cells and mTOR channels. It controls many processes that affect cell growth and reproduction. This is one of the "master switches" researchers are looking for. It is also our human body. All cells can not only control the speed of aging, but also a channel for diseases such as heart disease, cancer and Alzheimer's disease. This channel receives signals from hormones and nutrients. When food is sufficient, it will send out a signal to make cells absorb nutrients and grow. In this process, the metabolism and growth of cells will produce by-products that stimulate cell senescence. I will. When food calorie intake is restricted, the channel can send a signal to prevent cell growth, thereby delaying aging. The advantage of rapamycin as an anti-aging drug is that it can block the mTOR channel without restricting food calorie intake.

　　B, manipulate genes to extend life

　　In the 1930s, Clive McKay, a nutritionist at Cornell University, discovered that mice with restricted food caloric intake lived longer than other mice. done. Facts have proved that restricting food calorie intake during the same period can prolong the lifespan of yeast, stachys, ginger flies and non-human primates.

　　But so far, humans have little understanding of the principle of limiting food calorie intake to extend life. In the process of decomposing food free radicals, it is possible to reduce the harmful by-products produced by cells, thereby reducing the pressure on the cells. Rapamycin mimics the restriction of food calorie intake by blocking the mTOR signal channel. In addition, Harvard University researcher David Sinclair (David Sinclair) is dedicated to studying another channel of the genome, that is, Certuin. Like mTOR, the SIRT1 gene in this genome may be the key to extending life and preventing age-related diseases.

　　SIRT1 gene is the switch that controls food calorie intake. In 2003, Sinclair and his colleagues discovered resveratrol, a natural compound found in grapes, red wine and certain nuts. The compound turns on the SIRT1 gene and can extend the lifespan of yeast by 70%. Next, the researchers fed the two groups of mice a high-fat diet, but a group of resveratrol-fed mice lived longer than non-resveratrol-fed mice. However, in mice that did not eat a high-fat diet and ate normally, resveratrol did not show a very obvious life-prolonging effect. The results of this and other studies cast doubt on the anti-aging effects of resveratrol.

　　There are more than 4,000 studies on resveratrol, but there are very few studies on humans. Therefore, it is too early to determine whether resveratrol is effective in delaying and preventing aging.

　　In addition, researchers are still looking for other ways to manipulate genes. Chromosomal telomeres are cap-like structures at the ends of chromosomes that shorten as cells divide and become potential targets. As the telomeres of the chromosomes get shorter and shorter, the cells divide and die. There is an enzyme involved in the elongation of telomeres, called telomerase. Telomerase fills in the defects in DNA replication, thereby prolonging the repair of telomeres, preventing cell division from losing telomeres and increasing the number of cell divisions. Ronald and his research team at the Danaferber Cancer Institute in Boston are studying ways to manipulate telomerase, looking for drugs that can enhance telomerase, especially for the treatment of rare diseases such as human premature aging. I will. Potential drugs. However, it is worth noting that the enhancement of telomerase promotes cell division and leads to tumor cells. Another Croto gene related to longevity gene was also discovered. Researchers have found that mice that do not carry the Klotho gene age faster and are more likely to develop senile diseases, but we will discuss whether the gene can be manipulated to delay aging. It's still too early.

　　C, anti-aging drugs participate in clinical trials

　　Compared with experimental animals, these studies have a breakthrough importance in extending human life, but cell channels and genes play a more complicated role in human aging. There are still many obstacles to overcome in the leap from mice to humans. For example, the ability of rapamycin to extend lifespan in invertebrates and mice is exciting, but rapamycin has no side effects because it has not been seen whether it has the same effect on humans. It will increase cholesterol and blood pressure. In 2012, a report on the long-term use of rapamycin in mice showed that rapamycin can increase the possibility of cataracts and testicular degeneration in mice. Another unresolved problem is that although rapamycin can delay aging, people are more susceptible to bacterial and viral infections. Therefore, it is not the perfect longevity medicine. Although the method of restricting food calorie intake has been generally accepted, scientists still do not know whether long-term food calorie intake is harmful to human nutrition and health. In addition, although food calorie restriction has achieved exciting results in the laboratory, this method does not seem to have much effect on wild mice. Currently, researchers are studying primates, but there is still a long way to go.

　　So far, the idea of quickly shutting down or reversing primitive human biological systems is fantasy. We need to conduct more detailed studies on the mechanisms of human aging. Some drugs have shown anti-aging properties in the laboratory, but it is not clear whether they can work safely in the human body. This requires clinical trials for verification.

　　This attempt has already begun. The US Food and Drug Administration recently approved the world's first anti-aging drug, metformin, for clinical trials. The drug has been used to treat diabetes in the past and has been successfully used in the laboratory. life. Successful clinical trials are expected to prolong life and delay the onset of senile diseases. In other words, we hope that mankind can take new steps towards the goal of "immortality" and pursue humanity's "immortality." Add a strong brushstroke to it. At the same time, what we cannot ignore is the need for a balanced diet and regular exercise to effectively delay aging and prevent aging-related diseases.