SpaceX's Dragon set to deliver beating human heart tissue to the ISS

Long-term microgravity exposure causes various biological changes, ranging from bone loss to changes in cardiovascular function. 

Towards this, SpaceX's Dragon cargo ship is set to deliver cardiac tissue chips to the International Space Station (ISS). According to NASA, the cargo spacecraft is expected to autonomously dock with the ISS at 7:52 am EDT Thursday, March 16.

The space station is located in low-Earth orbit, over 250 miles above the planet, and houses the ISS National Lab. This space lab conducts various biological experiments to test drugs and cellular therapies to address health complications caused by microgravity.

Experiments on beating heart tissues 

The heart tissue chips will be used to conduct two studies — cardinal heart 2.0 and engineered heart tissues-2 — addressing health complications caused by microgravity

Cardinal heart 2.0 is a follow-up experiment to the first, which demonstrated that four weeks of microgravity exposure affected cell function and gene expression in the heart. For this, NASA uses heart organoids and 3D structures to test the efficacy of clinically approved drugs on heart issues caused by a prolonged stay in the microgravity environment. 

The engineered heart-tissues study, on the other hand, aims to closely monitor how the heart muscle functions in microgravity. This is done through the use of 3D cultured cardiac muscle tissue.

The experiment is based on cardiomyocytes — the heart muscle responsible for contraction. These cells are grown using stem cells, which are the body's raw cells. Stem cells can be transformed into many different cell types, including cardiac muscle, nerve, and vascular cells. 

The experiment employs a magnet that is synced with muscle cell contraction. The equipped sensors monitor the muscle contractions in real time as the magnet moves. As a result, scientists can better study cardiac function in microgravity.

Experiments hold the potential to develop better drugs

According to scientific evidence, the human heart can shrink under the influence of microgravity. This is due to the fact that weightlessness changes the structure of the heart. This is especially dangerous for astronauts and can lead to medical complications.

Furthermore, NASA's research using 3D cultures revealed changes at the cellular and tissue levels of the heart as well. Having a knowledge of such changes could lead to an early diagnosis of the development of cardiac disease, says NASA.

The 3D models could significantly improve medical research and make it easier to test drugs to solve microgravity-related heart issues. In the near term, the ISS studies could be useful in addressing heart-related issues on Earth. The NASA statement reveals that over 600,000 people die annually due to cardiovascular diseases in the United States alone. And in the future term, for space-faring astronauts.  

The Tissue Chips in Space initiative, a joint project of the National Institutes of Health and the ISS National Laboratory, has taken the initiative in these ongoing experiments.