It's a colloquial thing we do, speaking of our body parts like they have personalities. You know: "my gut told my brain to slow down before I make myself sick."
They don't really speak English (or any other human language), but our body cells do have conversations, in a way. They have systems for communicating with each other, relaying necessary information to keep the body healthy.
John Lieff, physician and neuroscientist, gives us a sense of what the communication is like, in his book The Secret Language of Cells. The author shares findings from his own work and those of other scientists.