Scientists discover a new synthetic molecule that reverses bone loss in astronauts

A newly engineered compound has shown promise in mice onboard the International Space Station (ISS) to prevent microgravity-induced bone loss.  A multidisciplinary team of researchers from the University of California, Los Angeles (UCLA) and the Forsyth Institute in Cambridge, Massachusetts developed this novel synthetic molecule based treatment.

As per the official release, this could reduce the risk of  developing "extreme bone loss from long-duration space travel as well as musculoskeletal degeneration on Earth.”

To develop the new molecule the scientists delved into the medicinal attributes of a protein referred to as 'NELL-like molecule-1 (NELL-1),' which holds a crucial function in the overall growth and upkeep of human bone structures.

Over recent years, there has been an effort among researchers to investigate the significance of NELL-1 in bone biology, driven by the objective of formulating potential regenerative remedies for conditions associated with the skeletal system.

In this latest research, the therapeutic capacity of NELL-1 was amplified through the development of a "smart BP-NELL-PEG molecule capable of pinpointing bone tissues with precision."

The modified molecule was tested on mice who were subjected to microgravity for nine weeks on the ISS. In a corresponding control experiment, another group of mice stayed on Earth and received a similar treatment with BP-NELL-PEG.

In the overall evaluation, both flight and ground mice treated with BP-NELL-PEG demonstrated a considerable increase in bone formation. Importantly, neither the space-exposed mice nor the Earth-based ones exhibited any apparent adverse health consequences.

This advancement might have a huge impact on the treatment of severe osteoporosis and other bone-related disorders on Earth.

“If human studies bear this out, BP-NELL-PEG could be a promising tool to combat bone loss and musculoskeletal deterioration, especially when conventional resistance training is not feasible due to injuries or other incapacitating factors,” said Kang Ting, co-co-principal investigator.

Scientists have been working hard to find potential solutions to the bone health risks linked with space flight. Various astronaut-based studies have already revealed that prolonged exposure to low-gravity conditions can lead to a loss in bone density.

Mechanical loading is a natural process that occurs on Earth that controls bone mass. Activities like stretching, weightlifting, exercise routines, and various movements exert physical forces and stresses on bones, triggering the process of bone remodelling and growth.

In contrast, reduced or altered mechanical loading, such as under microgravity circumstances, can result in bone loss and decreased bone density.

This recent study underscores that the decrease in mechanical loading due to microgravity leads to bone loss occurring at a rate 12 times greater than what is typically observed under terrestrial conditions.

Astronauts aboard the ISS could experience bone loss of as much as one percent per month. This presents a significant concern for their skeletal well-being, increasing the likelihood of fractures during prolonged space missions and potentially affecting their bone health in later stages of life upon returning to Earth.

The current approach to reducing bone loss mostly relies on exercise-induced mechanical stress to promote bone growth, but it is not well-suited for crew members who stay for up to six months in a microgravity environment.

Finding efficient therapeutic strategies to reduce bone loss will be critical as space agencies plan longer and more distant trips, such as those to Mars, to ensure the health and safety of astronauts during and after their mission.

“Our findings hold tremendous promise for the future of space exploration, particularly for missions involving extended stays in microgravity,” said lead corresponding author Chia Soo.

The new study results have been published in the journal npj Microgravity.