Monomethyl Fumarate (MMF, Monomethylfumarate, Fumaric acid monomethyl ester, Methyl hydrogen fumarate), the active metabolite of the psoriasis drug Fumaderm, is a potent GPR109A agonist. Monomethyl Fumarate prevents major dysfunctions associated with neurodegenerative diseases: oxidative stress, mitochondrial dysfunction, apoptosis and autophagy.