Bamboo needles losing finish

I’ve been using my beloved bamboo needles but their finish is starting to fade a bit and I’ve encountered a few snags. Has anyone else tried refinishing them or sanding them? I’m kind of, well, very devoted to bamboo needles and would like to keep my investment. Any ideas?

I’ve never tried it but have heard that a very very fine sand paper used lightly will help as does rubing them w/ waxed paper.