Bring up

Literal definition: bring + up = to move or transfer by carrying from a lower location/position to a higher location/ position.

He brought the chest up the stairs by himself.
They brought the wine up from the cellar.
They brought up the player from the minor leagues.

Figurative definition 1: bring up = to introduce or raise a subject for discussion
While you are meeting with them, be sure to bring up pay compensation.
Susan brought up an interesting point in our discussion this morning.

Figurative definition 2: bring up = to care for over an extended period of time; to raise
The child had very irresponsible parents and was ultimately brought up by his aunt.
My mom brought me up to be an honest person.

Bring down

Literal definition: bring + down = to move or transfer by carrying from a higher location/position to a lower location/ position.

She brought down the box of old photos from the attic.
The pilot was able to bring down the plane with only one engine.

Figurative definition 1: bring down = to cause the downfall of a ruler, authority, or dominating figure.
The dictator was brought down by the revolt.
The new boy band’s new hit brought down the previous No. 1 song.

Figurative definition 2: bring down = to cause to fall, as from a shot or blow.
In 1989 the power of political socialism failed and they brought down the Berlin wall.
The missile brought down the plane.

Figurative definition 3: bring down = to cause someone to feel sad or depressed.
Dealing with the unexpected death of her father has really brought her down.
Hearing other people complain really brings me down.