I'm pretty sure Japan is 100VAC, not 110. It doesn't matter though, really.
The only part that will matter will be the power supply, which is external on these systems and can just be replaced with a US one, or whatever region you live in. The only piece of electronics I've seen that couldn't cope with US voltage specs is an original PS a guy I knew bought at the Japanese launch. It would overheat really badly. You had to open the door, tape the button down, and blow a fan on it to keep the thing from glitching out. In hindsight this probably had less to do with voltage differences and more to do with the fact that the PS is a POS.