1.
If someone shakes up something such as an organization, an institution, or a profession, they make major changes to it.
The government wanted to reform the institutions, to ~ the country...
Shareholders are preparing to shake things up in the boardrooms of America.
PHRASAL VERB: V P n (not pron), V n P
see also shake-up
2.
If you are shaken up or shook up by an unpleasant experience, it makes you feel shocked and upset, and unable to think calmly or clearly.
The jockey was shaken up when he was thrown twice from his horse yesterday...
He was in the car when those people died. That really shook him up...
PHRASAL VERB: be V-ed P, V n P