  We review our contribution to infrared Renormalization Group (RG) effects to
General Relativity in the context of galaxies. Considering the effective action
approach to Quantum Field Theory in curved background, we argued that the
proper RG energy scale, in the weak field limit, should be related to the
Newtonian potential. In the galaxy context, even without dark matter, this led
to a remarkably small gravitational coupling G variation (about or less than
10^{-12} of its value per light-year), while also capable of generating galaxy
rotation curves about as good as the best phenomenological dark matter profiles
(considering both the rotation curve shape and the expected mass-to-light
ratios). Here we also comment on related developments, open issues and
perspectives.
