The invention relates to inhibitors of MAPK3(ERK1 MAP kinase), in particular to polypeptides having the ability to stimulate the global ERK signalling pathway in the brain and their use as neuroprotective and/or cognitive enhancing agents.The invention also concerns related polynucleotides, vectors, host cells and pharmaceutical compositions able to inhibit MAPK3, causing the stimulation of the global ERK signalling pathway.Additionally, use of the afore inhibitors or stimulators in the treatment of neurodegenerative or neuropsychiatric disorders and cognitive impairment is also disclosed.
