Therapeutic Approach to Neurodegenerative Disorders Using a TFP5-Peptide

This invention discloses methods for treating neurodegenerative diseases by administering cyclin dependent kinase 5 (Cdk5) inhibitory peptides derived from P35, the activator of Cdk5. Abnormally hyperactive Cdk5 has been shown to be associated with a variety of neurodegenerative disorders. Disclosed in this invention are isolated peptide fragments, pharmaceutical compositions and methods for use of such for treating subjects with a neurodegenerative disease, such as Alzheimer’s disease (AD), Amyotrophic Lateral Sclerosis (ALS) and Parkinson’s disease (PD). An inhibitory fragment, TFP5, disclosed in this invention, has been shown to ameliorate symptoms of AD in disease animal models without any evidence of toxicity. In particular, TFP5 treatment of rat cortical neurons reduced hyperactivation of Cdk5 upon neuronal stress and insults. Following intraperitoneal (ip) injection, TFP5 was capable of crossing the BBB and localizing within the brain where it was found to rescue memory deficits and pathology in a double transgenic mouse (APP/PS1) AD model.