Phrasal Verb: Brush up Example: She took a two-week course to BRUSH UP her Spanish before she travelling around South and Central America.
Do you use these phrases in the same sense?
I'm not familiar with the first phrase , especially not with that meaning. I wonder if perhaps it's similar to RUB UP AGAINST, as in a cat rubbing up against your leg. However, a little googling shows me several online dictionaries that contain the meaning you've listed. It seems to be a British English usage.
With the second phrase, at least here in the US it's more common to hear BRUSH UP ON xxxx. Maybe I need to brush up on my British English