The 5 pointed star is the symbol of man and represents the proper use of the energy as it moves first through the spiritual chakra then down to the rest of the body. The is the proper use of energy.
The inverted pentagram is the opposite. Being upside down, the energy enters through the body at the lowest chakra, which deals with basic material needs. In this way the energies flow from the lower chakra to the others, with the emphasis on the material. I like to refer to this as being ass backwards.
It is important to know the difference.