  In $\mathbb{R}^n$ with a density $e^\psi$, we study the mean curvature flow
associated to the density ($\psi$-mean curvature flow or $\psi$MCF) of a
hypersurface. The main results concern with the description of the evolution
under $\psi$MCF of a closed embedded curve in the plane with a radial density,
and with a statement of subconvergence to a $\psi$-minimal closed curve in a
surface under some general circumstances.
