ABCC6 and pseudoxanthoma elasticum (inherited or acquired): The role of magnesium as a potential anticalcifying agent in PXE has been controversial with preclinical studies in Abcc6−/− mice showing that an increased magnesium intake substantially reduced ectopic calcification and cIMT in these animals, while a randomized clinical trial involving 44 PXE patients failed to identify a significant improvement of the skin phenotype following a 2-year period of oral magnesium supplementation [38,39,40].