It's hard to tell from the lighting but are they black painted or are they chromed? Camera settings along with the reflections can often disguise chrome surfaces.
The treatment for chrome and paint are similar but use different products. They've covered a trick for paint.
But if they are chromed then some chrome polish to clean them up as best you can and then a good cleaning and follow it with a good protective car wax.
Chrome, and a lot of paints for that matter, are quite pourous on a microscopic scale. Any paint, even the hardy clear over color combos, should have the protection of a good car wax once or twice a year. Regular washings may remove the surface wax after a time or two but the wax that gets into the pores is a lot harder to wash away and will provide protection for a long time. Chrome is especially bad for this. And thats why it gets surface stains on it and when you clean it away it SEEMS fine. But once it starts it's hard to keep the rust from coming back through these pores in the chrome.