Tardigrades, also known as water bears, are microscopic animals that are found in a variety of habitats, including freshwater, saltwater, and soil. They are known for their ability to survive extreme conditions, such as high temperatures, freezing temperatures, and even the vacuum of space.

One of the secrets to tardigrades' resilience is their ability to enter a state of suspended animation called cryptobiosis. During cryptobiosis, tardigrades' metabolism slows down to almost zero, and they can survive for long periods of time without food or water.

Scientists have been studying tardigrades in an effort to understand how they are able to survive such extreme conditions. They hope that this knowledge could lead to new treatments for human diseases that are characterized by excessive cell death, such as stroke, heart attack, and cancer.

In a recent study, researchers from the University of Tokyo found that tardigrade proteins can slow down metabolism in human cells. The researchers introduced tardigrade proteins into human cells and found that the cells' oxygen consumption and ATP production decreased significantly. The cells also showed a decrease in the production of reactive oxygen species (ROS), which are molecules that can damage cells.

The researchers believe that tardigrade proteins could be used to treat human diseases that are characterized by excessive cell death. By slowing down metabolism and reducing ROS production, tardigrade proteins could help to protect cells from damage and death.

The study is published in the journal Nature Communications.