To find better treatments for heart disease, researchers from Stanford shows promising results using an unusual strategy, photosynthetic bacteria and light.
Researchers are injecting a type of bacteria into the hearts of anesthetized rats with cardiac disease, then using light to trigger photosynthesis, they were able to increase the flow of oxygen and improve heart function.
Researcher Joseph Woo, said, the genesis of this mind-boggling concept sprang from scientists searching for new ways to deliver oxygen to the heart when blood flow is restricted. This condition, known as cardiac ischemia, is most often caused by coronary artery disease.
In nature, humans exhale carbon dioxide and plants convert it back to oxygen. During a heart attack, the muscle is still trying to pump. There’s carbon dioxide, but no oxygen. They wondered to use plant cells and put them next to heart cells to produce oxygen from the carbon dioxide.
Researchers first tried grinding up spinach and kale and combining each with heart cells in a dish, but the photosynthetic organs of those plants weren’t stable enough to survive outside of the plant cell.
Researchers said, they tried photosynthetic bacteria, referred to as cyanobacteria, or blue-green algae, since it has a more rugged structure necessary for living in the water.
After repeated the same tests, the photosynthetic bacteria had the ability to survive with heart cells in a dish.
The next experiments involved injecting the cyanobacteria into the beating hearts of anesthetized rats with cardiac ischemia. Researchers compared the heart function of rats with their hearts exposed to light for less than 20 minutes.
The group that received the bacteria plus light had more oxygen and the heart worked better. The bacteria dissipated within 24 hours, but the improved cardiac function continued for at least four weeks.
The researchers investigate how to apply this concept to humans and how to deliver a light source to the human heart.
Researchers also examining the potential of using artificial chloroplasts to eliminate the need for bacteria.
More information: [Science Advances]