Popeye ate it for strength, and it was the last thing you wanted for dinner. That's right — spinach. These days, the super food isn't just keeping hearts healthy — researchers are turning it into human tissue. 

1. The Problem

After a heart attack, part of the heart is permanently scarred. A team of biomedical engineers at Worcester Polytechnic Institute has been trying to engineer a heart tissue replacement that could restore function to damaged heart muscle, ideally reducing the need for heart transplants. A major stumbling block in this effort has been the inability of scientists to develop material through which blood could flow.

2. The Lightning Bolt

It happened not at the lab bench, but in a break room where Professor Glenn Gaudette and his graduate student, Josh Gershlak, were eating lunch.  A piece of fresh spinach caught Gershlak’s eye. He noticed, like human heart tissue, spinach also has a series of veins running through it that connected to a larger, central vein.

“And really, that stem, it shouted out to me," Gershlak said. "It was just like an aorta.”

3. The Crazy Idea

Doctors routinely transplant animal parts into people. One common surgery, for instance, is to replace a human heart valve with one from a pig. Putting part of a plant in a person, however, is definitely out-of-the-box thinking. Dr. Gaudette thought his student’s idea of testing spinach as a possible heart tissue replacement was worth a try, but he figured not everyone would see it that way.

“Josh came back to the lab and kind of secretly did this because we didn’t want people to think that we were crazy," said Gaudette.

4. The Spinach Transformation

Gershlak transformed the spinach through a process known as decellularizaiton.  A detergent drip strips away color and other cellular material, leaving a translucent, malleable substance, which, importantly, maintained its system of veins.

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Courtesy of Worcester Polytechnic Institute
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Courtesy of Worcester Polytechnic Institute
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To find out if the decellularized spinach leaf would work like human tissue, Gershlak injected red dye into the stem. The dye traveled throughout the veins, much like blood travels through human tissue.  

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The dye traveled through the spinach veins like blood travels through the heart.
Courtesy of Worcester Polytechnic Institute

Next, he planted heart cells on the transformed spinach leaves. The cells started beating.  

“It’s just incredible, something as whacky as spinach can support these cells," Gershlak said.

5.  The Future

Human testing is still years away, but the WPI researchers hope the engineered spinach tissue could one day be implanted in people to regenerate damaged areas of the heart. Gaudette calls his team’s success in transforming spinach into a potential heart tissue substitute “proof of concept." He says not just spinach, but a wide variety of other plants—from parsley to bamboo—may also have the potential to be engineered into life-saving materials.