First off....Welcome to LF! :D
Currently there are no native save game editors for the Mac. But you could try downloading Wine Bottler (
http://winebottler.kronenberg.org/), it allows you to run Windows programs natively on your Mac (don't worry it is free).
I have a mac too, but have never tried to use a save game editor this way. I have, however, used this method to install mods that use the TSL patcher. So, I do not know this will work.
What are you trying to do with the save game editor? Because there may be a simpler method to achieving what you want.