I don't think ceramic coating will reduce friction though. That one is another coating (eg. graphite, MoS2 etc....)If you are referring to ceramic, then the answer is yes. I don't know what improvements you mean but generally, by doing this you help reduce friction and also I think the lubrication can protect these parts from wear and damage.
I think we are all referring to different type of ceramic coating. Thermal coating such as Boron Nitride is meant for thermal purpose, not friction reduction. The ceramic coating on your exhaust headers is another eg. These ceramic coatings are not meant for bearing surfaces.how does it destroy the engine when nano ceramic coat to all the internal engine bearing & all metal parts?