No. You could perform manual checks on the data yourself, but this is obviously not the kind of automatic enforcing you are probably looking for.
That said, AF Tables are mainly designed to link or import data from other sources, including Relational Database Management Systems (RDBMS's) such as Microsoft SQL Server and Oracle. They are not intended to replace those RDBMS's nor is it where we intend users to create the bulk of their tables. In other words, the bulk of your data and all related logic (unique keys, triggers, etc.) should remain on the RDBMS side since that's what they do best.