Hi, Lori. One advantage to the brass plating is that the plating is not easily removed. The clear lacquer that is probably over the brass plating can be worn off but the plating will remain.
One of the problems with paint is that it can be easily worn or chipped off. This will be a lot more evident if you use a faux finish like sponging or any other kind of "decorative painting. I really would suggest that you stick with one color on this and save the decorative painting for other items in the room.
I believe that I would start with a test with lacquer thinner to see if it will remove the clear coat. This is very flammable so be sure to read and follow the label directions. And leave any rags that you use outside for a couple of days to dry completely. Wipe the lacquer thinner soaked rag on a place that looks the shiniest but is away from a heavy wear area. Probably down on the footboard is a good spot. It the lacquer thinner seems to remove a clear finish, keep going over the whole bed frame.
Whether the lacquer thinner worked or not, sand lightly with 400 grit wetordry paper, then tack rag to get off all the dust. Then spray with automotive primer. Auto parts stores and mass merchandises usually have a good selection of paints in automotive colors. Choose one of these and a primer in a similar color. When you spray any of these, you will have plenty of overspray so put a lot of newspaper on the floor and on other nearby surfaces to protect them. Spraying many light coats is a lot better than one heavy coat. Read and follow the instructions on the spray cans. You will probably need 2-3 spray cans because you will lose a lot to overspray.
After 2 coats of the automotive paint have dried completely--a day or two--your bed should be ready for use.