Another option is to cover them with sticky shelf liners or oil cloth. Or replace them. Check out Ikea as well as HD.

use gloss paint

Not sure the reasoning behind changing them this is a place where no one but you sees I think I would save my money and spend it somewhere else . Not sure about the walnut part but to honest that makes no sense unless you are now going to make this a butlers pantry in which case the whole thing needs a redo and all the food needs to go somewhere else . Maybe some more info would help me.