Neuroprotective and reparative effects of endoplasmic reticulum luminal proteins - mesencephalic astrocyte-derived neurotrophic factor and cerebral dopamine neurotrophic factor

Abstract

Cerebral dopamine neurotrophic factor (CDNF) and mesencephalic astrocyte-derived neurotrophic factor (MANF) are proteins that have received increasing attention in the last decades. Although they are called neurotrophic factors they are drastically different from neurotrophic factors in their expression and physiological actions. They are located in the lumen of the endoplasmic reticulum (ER) and their basal secretion from neurons is very low. However their secretion is stimulated upon ER calcium depletion by chemical probes such as thapsigargin, a sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) pump inhibitor. Exogenous MANF and CDNF possess therapeutic properties in several neurological disease models, including Parkinson disease and stroke. Endogenous MANF expression has been shown to be neuroprotective, as well as administration of either CDNF or MANF into the extracellular space. In this review, we focus on their therapeutic effects, regulation of expression and secretion, comparison of their mechanisms of action, and their application to the brain parenchyma as recombinant proteins.

Figure 1

The number of publications on MANF and CDNF since the first paper describing their molecular characterization and therapeutic effects. Source Scopus, March 11, 2019. MANF was searched with keywords Armetl1 OR MANF OR mesencephalic astrocyte-derived neurotrophic factor in the title, abstract, and keywords. CDNF was searched with Armetl1 OR CDNF or cerebral dopamine neurotrophic factor in the title, abstract, and keywords.