This is one of the dumber ideas that has been hanging around neurochemistry for the past 25 years. The blood-brain-barrier is there for a good reason; to protect the brain from a lot things in the blood that should never enter it. That’s why I don’t hear much talk about “breaking the gut barrier” to induce leaky gut syndrome for exactly the same reason.
For years the darndest thing kept happening to drugs in clinical trials to treat brain disorders: They never made it to the brain. For pharmaceutical companies this problem was as costly-developing treatments for the central nervous system takes an average of 15 years and $1.5 billion-as it was, in hindsight, kind of obvious.