About 610,000 people die of a heart attack every single year in the US – roughly one in four deaths. They are often caused when a blood clot stops the blood flowing into the heart, but in some cases, hypoxia – a lack of oxygen – can also induce one. When this happens, the heart tissue gets damaged, which triggers the attack.

Blood-thinning drugs and treatments can be used in the case of a blood clot-based attack, but hypoxia, which can also occur long after an initial attack, is sometimes a more troublesome beast to vanquish. A new study published in the journal Science Advances, however, may have come up with a rather novel way of doing just that, and rather bizarrely, it involves algae.

A team at Stanford University’s School of Medicine took their inspiration from the abundance of plant life around them. Photosynthesis, as any high school student knows, uses light, carbon dioxide, and water to manufacture glucose and oxygen. From vegetation to algae, it’s happening all over the planet – and without it, our world would be very different indeed.

These scientists suspected that if they injected some photosynthetic vegetation into the damaged heart tissue of a patient suffering from hypoxia, then – providing it still got some light – it would pump out oxygen directly into the cells and revive them.

First off, they had to find the right plants to use. Taking spinach and kale, they ground them into a fine powder and introduced them to living tissue being cultured within a Petri dish. Exposing them to sunlight, they were disappointed to find that photosynthesis refused to happen.

Suspecting the grinding process “broke” them, in a manner of speaking, the team decided to use blue-green algae, also known as cyanobacteria – the most primitive type of photosynthetic organism known to science.

Around 2.5 billion years ago, their ancestors were floating atop the world’s long-lost seas, slowly gulping up the volcanic carbon dioxide and pumping out oxygen. These little critters were ultimately responsible for the Great Oxygenation Event, the point in which oxygen was no longer being absorbed by the environment and could float freely in the atmosphere.

They’re actually responsible for turning our sky blue – and, having survived multiple mass extinctions over billions of years, it appears that injecting them straight into damaged heart tissue didn’t stop them doing their remarkable thing either.

Leaving the damaged hearts of rats open during the procedure, the sunlight-exposed algae happily infused these cells with precious oxygen, boosting their overall levels by a factor of 25. Overall, half of the damage due to hypoxia was ultimately prevented compared to the rats that didn’t have treatment.

Incredibly, there weren’t even any side effects to the procedure. There was no secondary infection, and the rats’ immune systems didn’t go haywire and try to destroy the cyanobacteria. Within just 24 hours post-injection, the algae had all but disappeared without a trace.

“By using light rather than blood flow as a source of energy, photosynthetic therapy increases tissue oxygenation, maintains myocardial [heart] metabolism, and yields durable improvements in cardiac function during and after induction of ischemia [lack of blood supply],” the team conclude in their study.

“This system has the potential to create a paradigm shift in the way ischemic heart disease is treated.”

So will algae be saving human lives in the future? At this point, it’s hard to say – the method is only at the proof-of-concept stage.

Leaving someone’s chest open will be very risky indeed, but the team are already working on “supercharging” their algae so they only require a little bit of light to get started. Even if they aren’t used in heart failure surgery, there’s a chance that they could be used to boost the longevity of organs being transported ready for transplantation.

[H/T: LA Times]