South SFV Today

Since the first astronauts ventured into space, scientists have observed that space travel affects the human body in unusual ways. Muscle and bone mass decrease, telomeres shorten, and risks for conditions like cancers, cataracts, and cardiovascular disease increase.

The exact reasons behind these accelerated aging effects in space remain largely unknown. However, researchers are increasingly focusing on this issue as civilian space travel becomes more feasible. Their findings could not only benefit future space travelers but also aid in treating various health conditions on Earth.

A recent study involving muscle samples sent to the International Space Station (ISS) revealed that the absence of gravity impairs the normal regenerative ability of skeletal muscle. Researchers from Stanford Medicine found similarities between muscle exposed to microgravity and muscle affected by sarcopenia, a condition characterized by muscle wasting in older adults.

"Microgravity is almost like an accelerated disease-forming platform and environment," said Ngan Huang, PhD, associate professor of cardiothoracic surgery and senior author of the study published in Stem Cell Reports. "It's important to understand how microgravity is affecting different tissues in the body."

Huang's team tested drugs that partially prevented these impairments in muscle samples. This research could benefit both terrestrial seniors and future space travelers.

"It's difficult to do clinical research on aging because you cannot tell the FDA that you've come up with a drug that can prolong life by five to 10 years -- it's very difficult to design that trial for logistical reasons," said Joseph Wu, MD, PhD, director of the Stanford Cardiovascular Institute.

Instead, researchers focus on specific markers associated with aging. Space provides a unique opportunity to study these markers over shorter timelines. Wu's lab has separately investigated microgravity's impact on heart tissue and found weakening similar to heart failure patients.

Huang's team discovered significant genetic changes in skeletal muscle samples exposed to microgravity. These changes indicated a shift toward lipid metabolism and cell death while showing impaired regeneration akin to sarcopenia.

"It's notable that in just seven days in microgravity, you see these profound effects," Huang said.

Some samples treated with drugs known to promote regeneration showed less impairment. Huang hopes this research will enhance muscle regeneration therapies for traumatic injuries common among veterans.

The new study underscores the value of using space as a platform for testing regenerative therapies. While it's clear gravity plays a foundational role in life on Earth, other factors like cosmic radiation must also be considered when evaluating space travel’s impact on health.

To further isolate microgravity effects, Huang plans experiments using devices simulating weightlessness here on Earth. Future solutions may involve hibernation strategies inspired by animals like squirrels and bears.

"If you can address microgravity, cosmic radiation and hibernation," Wu said, "then you can imagine a future where an astronaut or civilian can hop from one planet to another."

Researchers aim not only at advancing long-term space missions but also at discovering ways to slow aging or treat severe medical conditions through insights gained from studying life beyond Earth's atmosphere.

This story was originally published by Stanford Medicine SCOPE.

---