Our reporter Guo Guozhong Liu Lianjun correspondent Sun Zhenjiang Lu Minzhi
Insufficient sleep and circadian rhythm disorders can lead to intestinal barrier dysfunction and intestinal flora dysregulation, leading to the accumulation of reactive oxygen species in the intestine, causing oxidative stress and cell damage, which is the key to the body's metabolic dysfunction and further induction of sudden death.
Recently, a research report published in the international journal "Cell" said that researchers from Harvard Medical School found that the problem of staying up late for a long time is not the brain or heart, but the intestine.
The reason why long-term staying up late can cause premature death is due to the accumulation of oxides in the intestine. And the researchers further confirmed through experiments that by actively removing the oxides in the intestines of animals, even if they stay up late for a long time, their life expectancy is no different from that of animals that maintain normal work and rest.
This research report has aroused great concern in academia. So why does the accumulation of oxides in the intestine cause sudden death? What is the difference between this study and the previous understanding of the causes of staying up late? A reporter from Science and Technology Daily interviewed relevant domestic experts.
Staying up late has become the new normal in life
Earlier, the "Chinese Sleep Quality Survey Report" released by the Sleep and Respiratory Center of Beijing Chaoyang Hospital showed that 16% of the 100,000 respondents covering all provinces in the country had problems sleeping less than 6 hours; 83.81% were Investigators are often troubled by sleep problems, with difficulty falling asleep accounting for 25.83% and light sleepers for 26.49%.
In the opinion of experts, staying up late has become a new normal in life due to the influence of a series of factors, such as changes in lifestyle and increased pressure of social competition. However, staying up all night will cause great harm to our body.
Chu Weihua, an associate professor of China Pharmaceutical University who has long been engaged in intestinal probiotic and disease research, told reporters that staying up late will cause a large amount of oxides in the intestine, and reactive oxygen species (ROS) will accumulate in the intestine. Dr. Lin Min, the Second People's Hospital of Changzhou, Nanjing Medical University, explained that ROS is a general term for a class of active oxygenated compounds produced by aerobic metabolism of organisms, mainly including hydrogen peroxide, superoxide anions, hydroxyl radicals and so on.
Chu Weihua said that ROS will greatly damage DNA and other components of cells, destroying collagen and elastin based on skin elasticity, causing wrinkles and sagging. "ROS also stimulates pigment cells to produce large amounts of melanin, which in turn produces chloasma, butterfly spots, etc.; ROS also destroys cell membranes, preventing cells from absorbing nutrients from the outside, which in turn leads to cell death, aging of tissues and organs, and even induces cardiovascular disease , Neurological diseases, tumors and more than 200 diseases."
The body's cells maintain a dynamic balance of ROS production and digestion through multiple ways. Recent studies have revealed that ROS is involved in the normal physiological processes of cells and is closely related to cell proliferation, differentiation and apoptosis. "Insufficient sleep and circadian rhythm dysregulation can lead to intestinal barrier dysfunction and intestinal flora dysregulation, leading to the accumulation of ROS in the intestine (especially the small intestine), causing oxidative stress and cell damage, which leads to metabolic dysfunction and further The key to inducing sudden death." Lin Min said.
Intestinal flora plays a key role
Experts say that sleep is the basis of human and other animal life activities. Scientists have been studying sleep for a long time, trying to understand the secrets of sleep, but there are still many secrets about sleep that cannot be solved. As we all know, if people do not have enough sleep, there will be a series of serious consequences, including suffering from chronic sleep disorders, heart disease, type 2 diabetes, cancer, depression and other diseases.
The reporter learned that as early as 1983, some American scholars found that long-term sleep deprivation would cause animal death through research on rats. Afterwards, the scientists conducted decades of exploration, but they never found out the exact cause of death of animals without sleeping.
"In recent years, with the development of microbiome and intestinal metagenomics, scientists have found that the intestine is involved in the occurrence and development of various human diseases, and also found that the intestine can affect the activity of the brain, even through the brain-gut axis. Interact with the brain." Lin Min explained that the brain-gut axis is a system composed of the brain and intestines in the human body. The brain and intestine communicate with each other in the form of hormones and nerve messages, which together regulate human emotional response, metabolism, immune system, brain development and health.
Sleep is an important physiological process regulated by the brain. Some researchers have found that the intestine, especially the intestinal flora, may be a key regulator of sleep mechanism. Lin Min introduced that the intestinal tract participates in various physiological and pathological processes of the body, and also regulates the sleep awakening mechanism through nerve, endocrine, immunity and metabolism. Most studies believe that the regulation of intestinal flora on sleep is achieved through the combined action of multiple pathways in the brain-gut axis.
Professor Chen Yongquan, Dean of Wuxi Medical College of Jiangnan University, said: "Previous studies have suggested that sudden death caused by staying up late is related to cardiovascular disease. For example, people who already have certain cardiovascular diseases will suddenly have an accident after staying up late. But recently, some The young people who suffered sudden death did not have cardio-cerebrovascular diseases during their lifetime. Therefore, the above study of Harvard Medical School has subverted the traditional understanding of the causes of sudden death."
Antioxidants mitigate negative effects
Previous studies have shown that long-term sleep suppression will inevitably lead to premature animal death. In order to find the mechanism of death caused by sleep deprivation, most researchers have focused on the relevant research of the brain. After all, the brain is the main organ that controls sleep . However, in the course of studying the brain, no researchers have found useful clues.
According to Lin Min, in the study of Harvard Medical School, in order to find the cause of death of animals without sleeping, the researchers chose fruit flies as the experimental object. This is because the genes of Drosophila are very similar to humans, and the life cycle of Drosophila is short, so it is also suitable for observation.
It has been found that ROS accumulate in the intestines of animals with continuous sleep deprivation, which in turn induces the animals to die prematurely. Then, can artificial removal or neutralization of these oxides prolong the life of animals?
Researchers at Harvard Medical School found dozens of antioxidants that neutralize ROS. By supplementing these antioxidants with fruit flies, the researchers found that sleep-deprived fruit flies have a normal or near normal life span. At the same time, normal fruit flies supplemented these substances without any change in lifespan.
In other words, these antioxidants can extend the lifespan of sleep deprived fruit flies without any other effects. The researchers also used gene regulation to promote the expression of antioxidant enzymes in the intestine or brain of Drosophila. It was found that overexpression of antioxidant enzymes in the intestine can effectively extend the lifespan of fruit flies, while overexpression of antioxidant enzymes in the brain has no significant effect. .
Chu Weihua said that this not only further proves that ROS accumulation in the intestine plays a central role in death caused by sleep deprivation, but also suggests that eating antioxidant foods may help improve health problems caused by insufficient sleep.
"By neutralizing oxides and reducing oxidative stress in the intestine, you can offset the harm caused by insufficient sleep and extend the lifespan of insomniac animals. This is mainly achieved by supplementing antioxidants. It is worth mentioning that existing research shows that There are many probiotics with antioxidant activity." Chu Weihua said that in-depth study of the intestinal bacteria and sleep regulation related pathways and mechanism of action, undoubtedly provides new ideas for the treatment of sleep disorders.
However, some experts have suggested that although these studies have revealed that sleep disorders and intestinal flora can affect each other, researchers have not been able to figure out why lack of sleep can cause ROS accumulation in the gut and why it is so "fatal." So far, because the research on the relationship between the intestine and sleep disorders is still in its infancy, the specific mechanism of how sleep disorders affect intestinal changes is still at the stage of animal experiments, and there is a lack of large-scale clinical experimental studies on insomnia and intestinal problems. Therefore, in the future, a more in-depth study of the brain-gut axis may be required.