BEIJING, Nov. 13 (Xinhua) — The thought of space flight will give people hope for a wonderful space trip with a faster heartbeat, but in fact space travel beyond Earth can change human organ cells, including heart cells, the Daily Mail of London reported.
As astronauts work longer hours on the International Space Station, and as humans become more likely to spend longer in space due to mission factors, researchers need to better understand the effects of microgravity on human heart function.
New research shows that heart muscle cells derived from stem cells are highly environmentally adaptable during and after space flight, and scientists have been developing heart cells on the International Space Station for 38 days, testing cell-grade heart function and gene expression.
They found that human exposure to microgravity would alter thousands of gene expressions, but when astronauts returned to Earth within 10 days, heart tissue gradually returned to normal. “Our study is very novel because it is the first time that human-induced multi-functional stem cells have been used to study the effects of space flight on human heart function,” said Joseph Wu, senior author of the study and a professor at Stanford University School of Medicine. “
Microgravity is not well understood, and studies of the effects on the human body as a whole may help shed light on changes in the behavior of human cells in space, especially as more and longer-lasting space missions are needed in the future, such as landing on the moon and Mars.
Myocardial cells derived from stem cells are highly environmentally adaptable during and after space flight, and scientists have been growing heart cells on the International Space Station for 38 days, testing cell-grade heart function and gene expression
So far, most studies of the heart’s microgravity response have been conducted on non-human models, tissues, organs or systems, and in order to address the need for “living tests” in space, SpaceX has sent “beating” heart cells to the International Space Station for experimental analysis on commercial resupply missions, and Scientists are on the ground to develop heart cells as a test comparison.
When heart cells return to Earth, they show normal structural patterns, but they do develop arterial and calcium circulation patterns in the space environment, and after a 38-day trial on the International Space Station, scientists sequenced the cells and analyzed them, showing that 2,635 genes were sequenced during space flight. There are differences in the genetic expression of space flight and ground control samples.
Notably, according to a new study published in the journal Stem Cell Reports, gene pathways associated with mitochondrial function express more information about cell genes during space flight. By comparing sample data, heart cells used a unique gene expression pattern during space flight, which reverted to a ground-like pattern when returned to normal gravity.
Dr. Joseph Wu said that we were surprised by the speed at which human cardiomyocytes adapt to the environment, including microgravity, and that these studies may provide insight into cellular mechanisms, help astronauts stay healthy during long space flights, or provide new treatments for patients with heart disease. The study was published in the journal Stem Cell Reports.
How astronaut Scott Kelly’s DNA has changed in space
U.S. astronaut Scott Kelly returned to Earth in March 2016 after 340 days on the International Space Station. NASA has since used Kelly’s twin brother, Scott Mark, as a control object to study the impact of Kelly’s life in orbit.
The Kelly brothers have almost the same genome, which allows scientists to study the effects of long-term space flight on the human body. The researchers collected blood and other biological samples of the Kelly brothers before, during and after the space mission, and when Kelly returned home from a space mission, he accidentally found himself 5 cm taller than her twin brother and living on the ground for two days, the height difference faded.
Pictured is the American astronaut brother, pictured right, kelly, pictured left, and Mark, pictured left, who had just returned home from a space mission when he accidentally found himself 5cm taller than his twin brother, living on the ground for two days, and the height difference faded
Experts say the change in height is due to the global gravity conditions of the International Space Station, where astronauts’ spines are stretched, but the effects are only temporary.
NASA found that 93 percent of Kelly’s genes returned to normal shortly after returning home, while 7 percent of the genes were permanently altered. This long-term change destroys genes associated with the immune system, DNA repair, bone formation, and the way tissue absorbs oxygen and carbon dioxide, while Kelly’s telomeres (the cap-like structure at the end of chromosomes) grow in the space environment.
The important role of telomeres is to protect DNA from damage, but as you get older, telomeres become shorter, and when Kelly returns to the ground, the telomeres begin to shorten and return to normal.
NASA says Kelly’s telomeres grew in length because of his diet and daily exercise on the International Space Station, and that during his life in space, the ratio of two sets of gut bacteria also changed, possibly due to changes in diet in space, and he gradually returned to normal shortly after returning to earth.
NASA has found hundreds of different genetic mutations in Kelly and Mark’s genome, and the team speculates that the “space gene” of these mutations may have been activated by Kelly in the space environment.