Popeye was right: spinach really is good for the muscles, and not just the ones in your biceps. In fact, scientists have discovered a way to use the leafy stuff, which has a vascular system not dissimilar to ours, to grow layers of working heart muscle, according to a paper published this month in the journal Biomaterials. The new technique, a collaboration between Worcester Polytechnic Institute, the University of Wisconsin-Madison, and Arkansas State University-Jonesboro, marks a breakthrough in the field of human tissue regeneration, which has hitherto been stymied by scale. To wit, although current bioengineering methods can recreate cellular scaffolding on a large scope, fabricating branching networks of tiny blood vessels has proven far trickier.
But then scientists noticed that plants and animals evolved parallel means of distributing water and nutrients to their respective cells.
“Plants and animals exploit fundamentally different approaches to transporting fluids, chemicals, and macromolecules, yet there are surprising similarities in their vascular network structures,” the authors wrote. “The development of decellularized plants for scaffolding opens up the potential for a new branch of science that investigates the mimicry between plant and animal.”
To test their theory, the researchers stripped a bunch of spinach leaves of their cells, leaving behind a network of cellulose. They then seeded the spinach veins with beating human-heart cells. With the leaf fully networked, the team pumped fluids and microbeads through their pint-size proto-heart, mimicking the flow of human cells through our own arterial system.
So far, so successful. “We have a lot more work to do, but so far this is very promising,” said Glenn Gaudette, professor of biomedical engineering at WPI and corresponding author of the paper.
And it’s not just spinach that’s up for the job. Other decellularized plants could help deliver oxygen to damaged tissue in victims of heart attacks or other kinds of cardiac trauma.
Even better, bioengineers could tweak different plant species to repair a range of tissues in the body. Spinach might work best for highly vascularized cardiac tissue, for instance, but the cylindrical hollow structure of something like jewelweed might be more appropriate for an arterial graft. Similarly, the vascular columns of wood could one day play a role in healing human bones.
“Adapting abundant plants that farmers have been cultivating for thousands of years for use in tissue engineering could solve a host of problems limiting the field,” Gaudette added.