Scientists found a way to use spinach to build working human heart muscle (2017)

Now, scientists have used plant veins to replicate the way blood moves through human tissue. The team then bathed the remaining plant frame in live human cells, so that the human tissue grew on the spinach scaffolding and surrounded the tiny veins. Like blood vessels, the veins in the modified leaves would deliver oxygen to the entire swath of replacement tissue, which is crucial in generating new heart matter.

Source: news.nationalgeographic.com