  In this paper, after reconstructing the redshift evolution of the Hubble
function by adopting Gaussian process techniques, we estimate the best-fit
parameters for some flat Friedmann cosmological models based on a Modified
Chaplygin Gas interacting with dark matter. In fact, the expansion history of
the Universe will be investigated because passively evolving galaxies
constitute cosmic chronometers. An estimate for the present-day values of the
deceleration parameter, adiabatic speed of sound within the dark energy fluid,
effective dark energy, and dark matter equation of state parameters is
provided. By this, we mean that the interaction term between the two dark
fluids, which breaks the Bianchi symmetries, will be interpreted as an
effective contribution to the dark matter pressure similarly to the framework
of the "Generalized Dark Matter". We investigate whether the estimates of the
Hubble constant and of the present-day abundance of dark matter are sensitive
to the dark matter - dark energy coupling. We will also show that the cosmic
chronometers data favor a cold dark matter and that our findings are in
agreement with the Le Ch\^atelier-Braun principle according to which dark
energy should decay into dark matter.
