Azanone (HNO) interaction with Hemeproteins and metalloporphyrins

Abstract

Azanone (HNO), also called nitroxyl, is a highly reactive compound, with interesting yet poorly understood biological properties. Like its closely related sibling NO, its main biological targets are heme proteins, although significant differences in their reactivity and pharmacological effects are observed. Due to its high reactivity, azanone studies rely on the use of donors, molecules that therefore offer interesting therapeutic perspectives. In this review, we firstly describe the pharmacological potential of azanone, the chemistry of the available donors, and the main biological relevant HNO reactions with special focus on heme proteins and metalloporphyrins (Fe, Mn, and Co). Finally, we present evidence concerning the endogenous in vivo azanone production hypothesis, and how the recent porphyrin-based developed methods for its detection may contribute to solve this key physiological question.