This sounds like you want to implement some kind of version control.
I see different solution directions:
Depending on how you are going to use it, all of the above are valid implementations.
Ask yourself the process flow: Could there be more people changing the content (in the future)? What should happen if the same person changes the content twice? What should happen if first person 1 and then person 2 is changing the content?
And about the usage: Is it always required to load both values? How large can the value be? What is the retention time for both fields?