My honest advice to you: if you're ready to absolutely commit to this like a full-time job, it can help your GPA. These are graduate level courses (some courses overlap with the med school) and it is 15 credit hours of science, so it's an enormous challenge you have to be prepared for. Getting a great GPA in this progam is absolutely doable - I know many of my classmates who got 3.6 and above, but not without a lot - a LOT - of hard work.
I came in a little unprepared for how rigorous this program was and got a not great GPA first semester, which put a lot of pressure on this semester (and we just finished finals, so I don't actually know how my GPA will pan out this semester either). Just know what you're committing to, commit to it, manage your time well, and you will be fantastic! It's a hard program, but it really is a great experience in learning how to study for medical school!