Adrenomedullin: A vasoactive agent for sporadic and hereditary vascular cognitive impairment.

Adrenomedullin (AM) is an endogenous peptide mainly secreted from endothelial cells, which has multiple physiological actions such as anti-inflammation, vasodilation, vascular permeability regulation and angiogenesis. Blood AM levels are upregulated in a variety of pathological states including sepsis, severe COVID-19, acute ischemic stroke and vascular cognitive impairment with white matter changes, likely serving as a compensatory biological defense response against infection and ischemia. AM is currently being tested in clinical trials for ulcerative colitis, Crohn's disease, severe COVID-19 for its anti-inflammatory properties and in ischemic stroke for its additional angiogenic action. AM has been proposed as a therapeutic option for vascular cognitive impairment as its arteriogenic and angiogenic properties are thought to contribute to a slowing of cognitive decline in mice after chronic cerebral hypoperfusion. As AM promotes differentiation of oligodendrocyte precursor cells into mature oligodendrocytes under hypoxic conditions, AM could also be used in the treatment of CADASIL, where reduced oxygen delivery is thought to lead to the death of hypoxia-prone oligodendrocytes. AM therefore holds potential as an innovative therapeutic drug, which may regenerate blood vessels, while controlling inflammation in cerebrovascular diseases.