BrightSideOfLife
I am not so certain that serrapeptase would be effective in the brain as the blood brain barrier MIGHT affect it's usage. I do not know whether this would be an issue but it might be. I am a fan of serrapeptase but do not know for certain that it would be effective in the brain.
It might be worth you looking at the expanded/enhanced Linus Pauling therapy which uses nutrients to address circulatory disorders. These are things like high dose Vitamin C or better still liposomal vitamin C, Magnesium, L-Proline, L-Lysine and associated nutrients. Magnesium carbonate is fairly inexpensive and reacts in an acid/base reaction with acids such as ascorbic acid to form highly absorbable magnesium salts. Tri Methyl Glycine can also be helpful as it lowers homocysteine levels. Vitamin C is the key though as it is with all circulatory disorders in including heart disease.
If you look on the vitaminc foundation forum you should find pdf's documenting all the nutrients.
http://www.vitamincfoundation.org/forum
Extracts such as Grape Seed Extract can also be helpful. You would need to check whether anything conflicts with any medication that you are taking.