Change the stored procedure definer

To see the definers:

show procedure status;

You can change them like this:

UPDATE `mysql`.`proc` p SET definer = 'YournewDefiner' WHERE definer='OldDefinerShownBefore'

For example:

 UPDATE `mysql`.`proc` p SET definer = 'user@%' WHERE definer='root@%'

Be careful, because this will change all the definers for all databases.

You can update the definer in mysql.proc table against the required table/db...

update mysql.proc set definer='root@localhost' where name='t_p';