Spacer profile and insulating pane unit having such a spacer profile

A spacer profile for a spacer frame of an insulating pane unit includes a hollow profile body made of plastic with a chamber defined therein. The hollow profile body extends in a longitudinal direction and includes an inner wall, an outer wall, a first side wall and a second side wall, which are connected to the inner and outer walls to form the chamber. First and second reinforcing layers made of a metallic material respectively extend on the first and second side walls and partially on the outer wall so as to be spaced apart by a first distance. A diffusion barrier layer is formed directly on the outer wall between the first and second reinforcing layers and is connected thereto in a diffusion-proof manner in order to form a heat-insulating diffusion barrier. An insulating pane unit includes at least two panes with such a spacer frame disposed therebetween.