If you don't mind losing the history of your current shell terminal, you could also do
bash -l
That would fork your shell and open up another child process of bash. The -l parameter tells Bash to run as a login shell. This is required, because .bash_profile will not run as a non-login shell. For more information about this, read here.
If you want to completely replace the current shell, you can also do:
exec bash -l
The above will not fork your current shell, but replace it completely, so when you type exit it will completely terminate, rather than dropping you to the previous shell.